first commit

addons/9p/install.sh

@@ -0,0 +1,6 @@
+if [ "${1}" = "rd" ]; then
+  echo "Installing module for Plan 9 Resource Sharing Support (9P2000)"
+  ${INSMOD} "/modules/9pnet.ko"
+  ${INSMOD} "/modules/9pnet_virtio.ko"
+  ${INSMOD} "/modules/9p.ko" ${PARAMS}
+fi

addons/9p/manifest.yml

@@ -0,0 +1,28 @@
+version: 1
+name: 9p
+description: "Driver for Plan 9 Resource Sharing Support (9P2000)"
+available-for:
+  bromolow-3.10.108:
+    install-script: &script "install.sh"
+    modules: true
+  apollolake-4.4.180:
+    install-script: *script
+    modules: true
+  broadwell-4.4.180:
+    install-script: *script
+    modules: true
+  broadwellnk-4.4.180:
+    install-script: *script
+    modules: true
+  denverton-4.4.180:
+    install-script: *script
+    modules: true
+  geminilake-4.4.180:
+    install-script: *script
+    modules: true
+  v1000-4.4.180:
+    install-script: *script
+    modules: true
+  purley-4.4.180:
+    install-script: *script
+    modules: true

addons/9p/src/3.10.108/Makefile

@@ -0,0 +1,36 @@
+obj-m := 9p.o
+
+9p-objs := \
+	vfs_super.o \
+	vfs_inode.o \
+	vfs_inode_dotl.o \
+	vfs_addr.o \
+	vfs_file.o \
+	vfs_dir.o \
+	vfs_dentry.o \
+	v9fs.o \
+	fid.o  \
+	xattr.o \
+	xattr_user.o
+
+9p-y += cache.o
+9p-n += acl.o
+
+obj-m := 9pnet.o
+obj-m += 9pnet_virtio.o
+obj-n += 9pnet_rdma.o
+
+9pnet-objs := \
+        mod.o \
+        client.o \
+        error.o \
+        util.o \
+        protocol.o \
+        trans_fd.o \
+        trans_common.o \
+
+9pnet_virtio-objs := \
+        trans_virtio.o
+
+9pnet_rdma-objs := \
+        trans_rdma.o

addons/9p/src/3.10.108/acl.c

@@ -0,0 +1,375 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/posix_acl_xattr.h>
+#include "xattr.h"
+#include "acl.h"
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
+{
+	ssize_t size;
+	void *value = NULL;
+	struct posix_acl *acl = NULL;
+
+	size = v9fs_fid_xattr_get(fid, name, NULL, 0);
+	if (size > 0) {
+		value = kzalloc(size, GFP_NOFS);
+		if (!value)
+			return ERR_PTR(-ENOMEM);
+		size = v9fs_fid_xattr_get(fid, name, value, size);
+		if (size > 0) {
+			acl = posix_acl_from_xattr(&init_user_ns, value, size);
+			if (IS_ERR(acl))
+				goto err_out;
+		}
+	} else if (size == -ENODATA || size == 0 ||
+		   size == -ENOSYS || size == -EOPNOTSUPP) {
+		acl = NULL;
+	} else
+		acl = ERR_PTR(-EIO);
+
+err_out:
+	kfree(value);
+	return acl;
+}
+
+int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
+{
+	int retval = 0;
+	struct posix_acl *pacl, *dacl;
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
+		set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
+		set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
+		return 0;
+	}
+	/* get the default/access acl values and cache them */
+	dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
+	pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
+
+	if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
+		set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
+		set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
+	} else
+		retval = -EIO;
+
+	if (!IS_ERR(dacl))
+		posix_acl_release(dacl);
+
+	if (!IS_ERR(pacl))
+		posix_acl_release(pacl);
+
+	return retval;
+}
+
+static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
+{
+	struct posix_acl *acl;
+	/*
+	 * 9p Always cache the acl value when
+	 * instantiating the inode (v9fs_inode_from_fid)
+	 */
+	acl = get_cached_acl(inode, type);
+	BUG_ON(acl == ACL_NOT_CACHED);
+	return acl;
+}
+
+struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
+{
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
+		/*
+		 * On access = client  and acl = on mode get the acl
+		 * values from the server
+		 */
+		return NULL;
+	}
+	return v9fs_get_cached_acl(inode, type);
+
+}
+
+static int v9fs_set_acl(struct p9_fid *fid, int type, struct posix_acl *acl)
+{
+	int retval;
+	char *name;
+	size_t size;
+	void *buffer;
+	if (!acl)
+		return 0;
+
+	/* Set a setxattr request to server */
+	size = posix_acl_xattr_size(acl->a_count);
+	buffer = kmalloc(size, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+	retval = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
+	if (retval < 0)
+		goto err_free_out;
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = POSIX_ACL_XATTR_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = POSIX_ACL_XATTR_DEFAULT;
+		break;
+	default:
+		BUG();
+	}
+	retval = v9fs_fid_xattr_set(fid, name, buffer, size, 0);
+err_free_out:
+	kfree(buffer);
+	return retval;
+}
+
+int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid)
+{
+	int retval = 0;
+	struct posix_acl *acl;
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
+	if (acl) {
+		retval = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
+		if (retval)
+			return retval;
+		set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
+		retval = v9fs_set_acl(fid, ACL_TYPE_ACCESS, acl);
+		posix_acl_release(acl);
+	}
+	return retval;
+}
+
+int v9fs_set_create_acl(struct inode *inode, struct p9_fid *fid,
+			struct posix_acl *dacl, struct posix_acl *acl)
+{
+	set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
+	set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
+	v9fs_set_acl(fid, ACL_TYPE_DEFAULT, dacl);
+	v9fs_set_acl(fid, ACL_TYPE_ACCESS, acl);
+	return 0;
+}
+
+void v9fs_put_acl(struct posix_acl *dacl,
+		  struct posix_acl *acl)
+{
+	posix_acl_release(dacl);
+	posix_acl_release(acl);
+}
+
+int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+		  struct posix_acl **dpacl, struct posix_acl **pacl)
+{
+	int retval = 0;
+	umode_t mode = *modep;
+	struct posix_acl *acl = NULL;
+
+	if (!S_ISLNK(mode)) {
+		acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		if (!acl)
+			mode &= ~current_umask();
+	}
+	if (acl) {
+		if (S_ISDIR(mode))
+			*dpacl = posix_acl_dup(acl);
+		retval = posix_acl_create(&acl, GFP_NOFS, &mode);
+		if (retval < 0)
+			return retval;
+		if (retval > 0)
+			*pacl = acl;
+		else
+			posix_acl_release(acl);
+	}
+	*modep  = mode;
+	return 0;
+}
+
+static int v9fs_remote_get_acl(struct dentry *dentry, const char *name,
+			       void *buffer, size_t size, int type)
+{
+	char *full_name;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		full_name =  POSIX_ACL_XATTR_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		full_name = POSIX_ACL_XATTR_DEFAULT;
+		break;
+	default:
+		BUG();
+	}
+	return v9fs_xattr_get(dentry, full_name, buffer, size);
+}
+
+static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
+			      void *buffer, size_t size, int type)
+{
+	struct v9fs_session_info *v9ses;
+	struct posix_acl *acl;
+	int error;
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	/*
+	 * We allow set/get/list of acl when access=client is not specified
+	 */
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
+		return v9fs_remote_get_acl(dentry, name, buffer, size, type);
+
+	acl = v9fs_get_cached_acl(dentry->d_inode, type);
+	if (IS_ERR(acl))
+		return PTR_ERR(acl);
+	if (acl == NULL)
+		return -ENODATA;
+	error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
+	posix_acl_release(acl);
+
+	return error;
+}
+
+static int v9fs_remote_set_acl(struct dentry *dentry, const char *name,
+			      const void *value, size_t size,
+			      int flags, int type)
+{
+	char *full_name;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		full_name =  POSIX_ACL_XATTR_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		full_name = POSIX_ACL_XATTR_DEFAULT;
+		break;
+	default:
+		BUG();
+	}
+	return v9fs_xattr_set(dentry, full_name, value, size, flags);
+}
+
+
+static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
+			      const void *value, size_t size,
+			      int flags, int type)
+{
+	int retval;
+	struct posix_acl *acl;
+	struct v9fs_session_info *v9ses;
+	struct inode *inode = dentry->d_inode;
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	/*
+	 * set the attribute on the remote. Without even looking at the
+	 * xattr value. We leave it to the server to validate
+	 */
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
+		return v9fs_remote_set_acl(dentry, name,
+					   value, size, flags, type);
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+	if (!inode_owner_or_capable(inode))
+		return -EPERM;
+	if (value) {
+		/* update the cached acl value */
+		acl = posix_acl_from_xattr(&init_user_ns, value, size);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		else if (acl) {
+			retval = posix_acl_valid(acl);
+			if (retval)
+				goto err_out;
+		}
+	} else
+		acl = NULL;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = POSIX_ACL_XATTR_ACCESS;
+		if (acl) {
+			struct iattr iattr;
+
+			retval = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+			if (retval)
+				goto err_out;
+			if (!acl) {
+				/*
+				 * ACL can be represented
+				 * by the mode bits. So don't
+				 * update ACL.
+				 */
+				value = NULL;
+				size = 0;
+			}
+			iattr.ia_valid = ATTR_MODE;
+			/* FIXME should we update ctime ?
+			 * What is the following setxattr update the
+			 * mode ?
+			 */
+			v9fs_vfs_setattr_dotl(dentry, &iattr);
+		}
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = POSIX_ACL_XATTR_DEFAULT;
+		if (!S_ISDIR(inode->i_mode)) {
+			retval = acl ? -EINVAL : 0;
+			goto err_out;
+		}
+		break;
+	default:
+		BUG();
+	}
+	retval = v9fs_xattr_set(dentry, name, value, size, flags);
+	if (!retval)
+		set_cached_acl(inode, type, acl);
+err_out:
+	posix_acl_release(acl);
+	return retval;
+}
+
+const struct xattr_handler v9fs_xattr_acl_access_handler = {
+	.prefix	= POSIX_ACL_XATTR_ACCESS,
+	.flags	= ACL_TYPE_ACCESS,
+	.get	= v9fs_xattr_get_acl,
+	.set	= v9fs_xattr_set_acl,
+};
+
+const struct xattr_handler v9fs_xattr_acl_default_handler = {
+	.prefix	= POSIX_ACL_XATTR_DEFAULT,
+	.flags	= ACL_TYPE_DEFAULT,
+	.get	= v9fs_xattr_get_acl,
+	.set	= v9fs_xattr_set_acl,
+};

addons/9p/src/3.10.108/acl.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+#ifndef FS_9P_ACL_H
+#define FS_9P_ACL_H
+
+#ifdef CONFIG_9P_FS_POSIX_ACL
+extern int v9fs_get_acl(struct inode *, struct p9_fid *);
+extern struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type);
+extern int v9fs_acl_chmod(struct inode *, struct p9_fid *);
+extern int v9fs_set_create_acl(struct inode *, struct p9_fid *,
+			       struct posix_acl *, struct posix_acl *);
+extern int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+			 struct posix_acl **dpacl, struct posix_acl **pacl);
+extern void v9fs_put_acl(struct posix_acl *dacl, struct posix_acl *acl);
+#else
+#define v9fs_iop_get_acl NULL
+static inline int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
+{
+	return 0;
+}
+static inline int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid)
+{
+	return 0;
+}
+static inline int v9fs_set_create_acl(struct inode *inode,
+				      struct p9_fid *fid,
+				      struct posix_acl *dacl,
+				      struct posix_acl *acl)
+{
+	return 0;
+}
+static inline void v9fs_put_acl(struct posix_acl *dacl,
+				struct posix_acl *acl)
+{
+}
+static inline int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+				struct posix_acl **dpacl,
+				struct posix_acl **pacl)
+{
+	return 0;
+}
+
+#endif
+#endif /* FS_9P_XATTR_H */

addons/9p/src/3.10.108/cache.c

@@ -0,0 +1,415 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/jiffies.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <net/9p/9p.h>
+
+#include "v9fs.h"
+#include "cache.h"
+
+#define CACHETAG_LEN  11
+
+struct fscache_netfs v9fs_cache_netfs = {
+	.name 		= "9p",
+	.version 	= 0,
+};
+
+/**
+ * v9fs_random_cachetag - Generate a random tag to be associated
+ *			  with a new cache session.
+ *
+ * The value of jiffies is used for a fairly randomly cache tag.
+ */
+
+static
+int v9fs_random_cachetag(struct v9fs_session_info *v9ses)
+{
+	v9ses->cachetag = kmalloc(CACHETAG_LEN, GFP_KERNEL);
+	if (!v9ses->cachetag)
+		return -ENOMEM;
+
+	return scnprintf(v9ses->cachetag, CACHETAG_LEN, "%lu", jiffies);
+}
+
+static uint16_t v9fs_cache_session_get_key(const void *cookie_netfs_data,
+					   void *buffer, uint16_t bufmax)
+{
+	struct v9fs_session_info *v9ses;
+	uint16_t klen = 0;
+
+	v9ses = (struct v9fs_session_info *)cookie_netfs_data;
+	p9_debug(P9_DEBUG_FSC, "session %p buf %p size %u\n",
+		 v9ses, buffer, bufmax);
+
+	if (v9ses->cachetag)
+		klen = strlen(v9ses->cachetag);
+
+	if (klen > bufmax)
+		return 0;
+
+	memcpy(buffer, v9ses->cachetag, klen);
+	p9_debug(P9_DEBUG_FSC, "cache session tag %s\n", v9ses->cachetag);
+	return klen;
+}
+
+const struct fscache_cookie_def v9fs_cache_session_index_def = {
+	.name		= "9P.session",
+	.type		= FSCACHE_COOKIE_TYPE_INDEX,
+	.get_key	= v9fs_cache_session_get_key,
+};
+
+void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
+{
+	/* If no cache session tag was specified, we generate a random one. */
+	if (!v9ses->cachetag)
+		v9fs_random_cachetag(v9ses);
+
+	v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
+						&v9fs_cache_session_index_def,
+						v9ses);
+	p9_debug(P9_DEBUG_FSC, "session %p get cookie %p\n",
+		 v9ses, v9ses->fscache);
+}
+
+void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses)
+{
+	p9_debug(P9_DEBUG_FSC, "session %p put cookie %p\n",
+		 v9ses, v9ses->fscache);
+	fscache_relinquish_cookie(v9ses->fscache, 0);
+	v9ses->fscache = NULL;
+}
+
+
+static uint16_t v9fs_cache_inode_get_key(const void *cookie_netfs_data,
+					 void *buffer, uint16_t bufmax)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	memcpy(buffer, &v9inode->qid.path, sizeof(v9inode->qid.path));
+	p9_debug(P9_DEBUG_FSC, "inode %p get key %llu\n",
+		 &v9inode->vfs_inode, v9inode->qid.path);
+	return sizeof(v9inode->qid.path);
+}
+
+static void v9fs_cache_inode_get_attr(const void *cookie_netfs_data,
+				      uint64_t *size)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	*size = i_size_read(&v9inode->vfs_inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p get attr %llu\n",
+		 &v9inode->vfs_inode, *size);
+}
+
+static uint16_t v9fs_cache_inode_get_aux(const void *cookie_netfs_data,
+					 void *buffer, uint16_t buflen)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	memcpy(buffer, &v9inode->qid.version, sizeof(v9inode->qid.version));
+	p9_debug(P9_DEBUG_FSC, "inode %p get aux %u\n",
+		 &v9inode->vfs_inode, v9inode->qid.version);
+	return sizeof(v9inode->qid.version);
+}
+
+static enum
+fscache_checkaux v9fs_cache_inode_check_aux(void *cookie_netfs_data,
+					    const void *buffer,
+					    uint16_t buflen)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+
+	if (buflen != sizeof(v9inode->qid.version))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	if (memcmp(buffer, &v9inode->qid.version,
+		   sizeof(v9inode->qid.version)))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	return FSCACHE_CHECKAUX_OKAY;
+}
+
+static void v9fs_cache_inode_now_uncached(void *cookie_netfs_data)
+{
+	struct v9fs_inode *v9inode = cookie_netfs_data;
+	struct pagevec pvec;
+	pgoff_t first;
+	int loop, nr_pages;
+
+	pagevec_init(&pvec, 0);
+	first = 0;
+
+	for (;;) {
+		nr_pages = pagevec_lookup(&pvec, v9inode->vfs_inode.i_mapping,
+					  first,
+					  PAGEVEC_SIZE - pagevec_count(&pvec));
+		if (!nr_pages)
+			break;
+
+		for (loop = 0; loop < nr_pages; loop++)
+			ClearPageFsCache(pvec.pages[loop]);
+
+		first = pvec.pages[nr_pages - 1]->index + 1;
+
+		pvec.nr = nr_pages;
+		pagevec_release(&pvec);
+		cond_resched();
+	}
+}
+
+const struct fscache_cookie_def v9fs_cache_inode_index_def = {
+	.name		= "9p.inode",
+	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
+	.get_key	= v9fs_cache_inode_get_key,
+	.get_attr	= v9fs_cache_inode_get_attr,
+	.get_aux	= v9fs_cache_inode_get_aux,
+	.check_aux	= v9fs_cache_inode_check_aux,
+	.now_uncached	= v9fs_cache_inode_now_uncached,
+};
+
+void v9fs_cache_inode_get_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode;
+	struct v9fs_session_info *v9ses;
+
+	if (!S_ISREG(inode->i_mode))
+		return;
+
+	v9inode = V9FS_I(inode);
+	if (v9inode->fscache)
+		return;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  v9inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
+		 inode, v9inode->fscache);
+}
+
+void v9fs_cache_inode_put_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if (!v9inode->fscache)
+		return;
+	p9_debug(P9_DEBUG_FSC, "inode %p put cookie %p\n",
+		 inode, v9inode->fscache);
+
+	fscache_relinquish_cookie(v9inode->fscache, 0);
+	v9inode->fscache = NULL;
+}
+
+void v9fs_cache_inode_flush_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if (!v9inode->fscache)
+		return;
+	p9_debug(P9_DEBUG_FSC, "inode %p flush cookie %p\n",
+		 inode, v9inode->fscache);
+
+	fscache_relinquish_cookie(v9inode->fscache, 1);
+	v9inode->fscache = NULL;
+}
+
+void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	struct p9_fid *fid;
+
+	if (!v9inode->fscache)
+		return;
+
+	spin_lock(&v9inode->fscache_lock);
+	fid = filp->private_data;
+	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
+		v9fs_cache_inode_flush_cookie(inode);
+	else
+		v9fs_cache_inode_get_cookie(inode);
+
+	spin_unlock(&v9inode->fscache_lock);
+}
+
+void v9fs_cache_inode_reset_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	struct v9fs_session_info *v9ses;
+	struct fscache_cookie *old;
+
+	if (!v9inode->fscache)
+		return;
+
+	old = v9inode->fscache;
+
+	spin_lock(&v9inode->fscache_lock);
+	fscache_relinquish_cookie(v9inode->fscache, 1);
+
+	v9ses = v9fs_inode2v9ses(inode);
+	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  v9inode);
+	p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
+		 inode, old, v9inode->fscache);
+
+	spin_unlock(&v9inode->fscache_lock);
+}
+
+int __v9fs_fscache_release_page(struct page *page, gfp_t gfp)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	BUG_ON(!v9inode->fscache);
+
+	return fscache_maybe_release_page(v9inode->fscache, page, gfp);
+}
+
+void __v9fs_fscache_invalidate_page(struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	BUG_ON(!v9inode->fscache);
+
+	if (PageFsCache(page)) {
+		fscache_wait_on_page_write(v9inode->fscache, page);
+		BUG_ON(!PageLocked(page));
+		fscache_uncache_page(v9inode->fscache, page);
+	}
+}
+
+static void v9fs_vfs_readpage_complete(struct page *page, void *data,
+				       int error)
+{
+	if (!error)
+		SetPageUptodate(page);
+
+	unlock_page(page);
+}
+
+/**
+ * __v9fs_readpage_from_fscache - read a page from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpage_from_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	if (!v9inode->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_page(v9inode->fscache,
+					 page,
+					 v9fs_vfs_readpage_complete,
+					 NULL,
+					 GFP_KERNEL);
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		p9_debug(P9_DEBUG_FSC, "page/inode not in cache %d\n", ret);
+		return 1;
+	case 0:
+		p9_debug(P9_DEBUG_FSC, "BIO submitted\n");
+		return ret;
+	default:
+		p9_debug(P9_DEBUG_FSC, "ret %d\n", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpages_from_fscache - read multiple pages from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpages_from_fscache(struct inode *inode,
+				  struct address_space *mapping,
+				  struct list_head *pages,
+				  unsigned *nr_pages)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p pages %u\n", inode, *nr_pages);
+	if (!v9inode->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_pages(v9inode->fscache,
+					  mapping, pages, nr_pages,
+					  v9fs_vfs_readpage_complete,
+					  NULL,
+					  mapping_gfp_mask(mapping));
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		p9_debug(P9_DEBUG_FSC, "pages/inodes not in cache %d\n", ret);
+		return 1;
+	case 0:
+		BUG_ON(!list_empty(pages));
+		BUG_ON(*nr_pages != 0);
+		p9_debug(P9_DEBUG_FSC, "BIO submitted\n");
+		return ret;
+	default:
+		p9_debug(P9_DEBUG_FSC, "ret %d\n", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpage_to_fscache - write a page to the cache
+ *
+ */
+
+void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	ret = fscache_write_page(v9inode->fscache, page, GFP_KERNEL);
+	p9_debug(P9_DEBUG_FSC, "ret =  %d\n", ret);
+	if (ret != 0)
+		v9fs_uncache_page(inode, page);
+}
+
+/*
+ * wait for a page to complete writing to the cache
+ */
+void __v9fs_fscache_wait_on_page_write(struct inode *inode, struct page *page)
+{
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	if (PageFsCache(page))
+		fscache_wait_on_page_write(v9inode->fscache, page);
+}

addons/9p/src/3.10.108/cache.h

@@ -0,0 +1,139 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#ifndef _9P_CACHE_H
+#ifdef CONFIG_9P_FSCACHE
+#include <linux/fscache.h>
+#include <linux/spinlock.h>
+
+extern struct fscache_netfs v9fs_cache_netfs;
+extern const struct fscache_cookie_def v9fs_cache_session_index_def;
+extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
+
+extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
+extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
+
+extern void v9fs_cache_inode_get_cookie(struct inode *inode);
+extern void v9fs_cache_inode_put_cookie(struct inode *inode);
+extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
+extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
+extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
+
+extern int __v9fs_cache_register(void);
+extern void __v9fs_cache_unregister(void);
+
+extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
+extern void __v9fs_fscache_invalidate_page(struct page *page);
+extern int __v9fs_readpage_from_fscache(struct inode *inode,
+					struct page *page);
+extern int __v9fs_readpages_from_fscache(struct inode *inode,
+					 struct address_space *mapping,
+					 struct list_head *pages,
+					 unsigned *nr_pages);
+extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
+extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
+					      struct page *page);
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp)
+{
+	return __v9fs_fscache_release_page(page, gfp);
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page)
+{
+	__v9fs_fscache_invalidate_page(page);
+}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return __v9fs_readpage_from_fscache(inode, page);
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return __v9fs_readpages_from_fscache(inode, mapping, pages,
+					     nr_pages);
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{
+	if (PageFsCache(page))
+		__v9fs_readpage_to_fscache(inode, page);
+}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	fscache_uncache_page(v9inode->fscache, page);
+	BUG_ON(PageFsCache(page));
+}
+
+static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page)
+{
+	return __v9fs_fscache_wait_on_page_write(inode, page);
+}
+
+#else /* CONFIG_9P_FSCACHE */
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp) {
+	return 1;
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page) {}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return -ENOBUFS;
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return -ENOBUFS;
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{}
+
+static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page)
+{
+	return;
+}
+
+#endif /* CONFIG_9P_FSCACHE */
+#endif /* _9P_CACHE_H */

addons/9p/src/3.10.108/error.c

@@ -0,0 +1,247 @@
+/*
+ * linux/fs/9p/error.c
+ *
+ * Error string handling
+ *
+ * Plan 9 uses error strings, Unix uses error numbers.  These functions
+ * try to help manage that and provide for dynamically adding error
+ * mappings.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/jhash.h>
+#include <linux/errno.h>
+#include <net/9p/9p.h>
+
+/**
+ * struct errormap - map string errors from Plan 9 to Linux numeric ids
+ * @name: string sent over 9P
+ * @val: numeric id most closely representing @name
+ * @namelen: length of string
+ * @list: hash-table list for string lookup
+ */
+struct errormap {
+	char *name;
+	int val;
+
+	int namelen;
+	struct hlist_node list;
+};
+
+#define ERRHASHSZ		32
+static struct hlist_head hash_errmap[ERRHASHSZ];
+
+/* FixMe - reduce to a reasonable size */
+static struct errormap errmap[] = {
+	{"Operation not permitted", EPERM},
+	{"wstat prohibited", EPERM},
+	{"No such file or directory", ENOENT},
+	{"directory entry not found", ENOENT},
+	{"file not found", ENOENT},
+	{"Interrupted system call", EINTR},
+	{"Input/output error", EIO},
+	{"No such device or address", ENXIO},
+	{"Argument list too long", E2BIG},
+	{"Bad file descriptor", EBADF},
+	{"Resource temporarily unavailable", EAGAIN},
+	{"Cannot allocate memory", ENOMEM},
+	{"Permission denied", EACCES},
+	{"Bad address", EFAULT},
+	{"Block device required", ENOTBLK},
+	{"Device or resource busy", EBUSY},
+	{"File exists", EEXIST},
+	{"Invalid cross-device link", EXDEV},
+	{"No such device", ENODEV},
+	{"Not a directory", ENOTDIR},
+	{"Is a directory", EISDIR},
+	{"Invalid argument", EINVAL},
+	{"Too many open files in system", ENFILE},
+	{"Too many open files", EMFILE},
+	{"Text file busy", ETXTBSY},
+	{"File too large", EFBIG},
+	{"No space left on device", ENOSPC},
+	{"Illegal seek", ESPIPE},
+	{"Read-only file system", EROFS},
+	{"Too many links", EMLINK},
+	{"Broken pipe", EPIPE},
+	{"Numerical argument out of domain", EDOM},
+	{"Numerical result out of range", ERANGE},
+	{"Resource deadlock avoided", EDEADLK},
+	{"File name too long", ENAMETOOLONG},
+	{"No locks available", ENOLCK},
+	{"Function not implemented", ENOSYS},
+	{"Directory not empty", ENOTEMPTY},
+	{"Too many levels of symbolic links", ELOOP},
+	{"No message of desired type", ENOMSG},
+	{"Identifier removed", EIDRM},
+	{"No data available", ENODATA},
+	{"Machine is not on the network", ENONET},
+	{"Package not installed", ENOPKG},
+	{"Object is remote", EREMOTE},
+	{"Link has been severed", ENOLINK},
+	{"Communication error on send", ECOMM},
+	{"Protocol error", EPROTO},
+	{"Bad message", EBADMSG},
+	{"File descriptor in bad state", EBADFD},
+	{"Streams pipe error", ESTRPIPE},
+	{"Too many users", EUSERS},
+	{"Socket operation on non-socket", ENOTSOCK},
+	{"Message too long", EMSGSIZE},
+	{"Protocol not available", ENOPROTOOPT},
+	{"Protocol not supported", EPROTONOSUPPORT},
+	{"Socket type not supported", ESOCKTNOSUPPORT},
+	{"Operation not supported", EOPNOTSUPP},
+	{"Protocol family not supported", EPFNOSUPPORT},
+	{"Network is down", ENETDOWN},
+	{"Network is unreachable", ENETUNREACH},
+	{"Network dropped connection on reset", ENETRESET},
+	{"Software caused connection abort", ECONNABORTED},
+	{"Connection reset by peer", ECONNRESET},
+	{"No buffer space available", ENOBUFS},
+	{"Transport endpoint is already connected", EISCONN},
+	{"Transport endpoint is not connected", ENOTCONN},
+	{"Cannot send after transport endpoint shutdown", ESHUTDOWN},
+	{"Connection timed out", ETIMEDOUT},
+	{"Connection refused", ECONNREFUSED},
+	{"Host is down", EHOSTDOWN},
+	{"No route to host", EHOSTUNREACH},
+	{"Operation already in progress", EALREADY},
+	{"Operation now in progress", EINPROGRESS},
+	{"Is a named type file", EISNAM},
+	{"Remote I/O error", EREMOTEIO},
+	{"Disk quota exceeded", EDQUOT},
+/* errors from fossil, vacfs, and u9fs */
+	{"fid unknown or out of range", EBADF},
+	{"permission denied", EACCES},
+	{"file does not exist", ENOENT},
+	{"authentication failed", ECONNREFUSED},
+	{"bad offset in directory read", ESPIPE},
+	{"bad use of fid", EBADF},
+	{"wstat can't convert between files and directories", EPERM},
+	{"directory is not empty", ENOTEMPTY},
+	{"file exists", EEXIST},
+	{"file already exists", EEXIST},
+	{"file or directory already exists", EEXIST},
+	{"fid already in use", EBADF},
+	{"file in use", ETXTBSY},
+	{"i/o error", EIO},
+	{"file already open for I/O", ETXTBSY},
+	{"illegal mode", EINVAL},
+	{"illegal name", ENAMETOOLONG},
+	{"not a directory", ENOTDIR},
+	{"not a member of proposed group", EPERM},
+	{"not owner", EACCES},
+	{"only owner can change group in wstat", EACCES},
+	{"read only file system", EROFS},
+	{"no access to special file", EPERM},
+	{"i/o count too large", EIO},
+	{"unknown group", EINVAL},
+	{"unknown user", EINVAL},
+	{"bogus wstat buffer", EPROTO},
+	{"exclusive use file already open", EAGAIN},
+	{"corrupted directory entry", EIO},
+	{"corrupted file entry", EIO},
+	{"corrupted block label", EIO},
+	{"corrupted meta data", EIO},
+	{"illegal offset", EINVAL},
+	{"illegal path element", ENOENT},
+	{"root of file system is corrupted", EIO},
+	{"corrupted super block", EIO},
+	{"protocol botch", EPROTO},
+	{"file system is full", ENOSPC},
+	{"file is in use", EAGAIN},
+	{"directory entry is not allocated", ENOENT},
+	{"file is read only", EROFS},
+	{"file has been removed", EIDRM},
+	{"only support truncation to zero length", EPERM},
+	{"cannot remove root", EPERM},
+	{"file too big", EFBIG},
+	{"venti i/o error", EIO},
+	/* these are not errors */
+	{"u9fs rhostsauth: no authentication required", 0},
+	{"u9fs authnone: no authentication required", 0},
+	{NULL, -1}
+};
+
+/**
+ * p9_error_init - preload mappings into hash list
+ *
+ */
+
+int p9_error_init(void)
+{
+	struct errormap *c;
+	int bucket;
+
+	/* initialize hash table */
+	for (bucket = 0; bucket < ERRHASHSZ; bucket++)
+		INIT_HLIST_HEAD(&hash_errmap[bucket]);
+
+	/* load initial error map into hash table */
+	for (c = errmap; c->name != NULL; c++) {
+		c->namelen = strlen(c->name);
+		bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
+		INIT_HLIST_NODE(&c->list);
+		hlist_add_head(&c->list, &hash_errmap[bucket]);
+	}
+
+	return 1;
+}
+EXPORT_SYMBOL(p9_error_init);
+
+/**
+ * errstr2errno - convert error string to error number
+ * @errstr: error string
+ * @len: length of error string
+ *
+ */
+
+int p9_errstr2errno(char *errstr, int len)
+{
+	int errno;
+	struct errormap *c;
+	int bucket;
+
+	errno = 0;
+	c = NULL;
+	bucket = jhash(errstr, len, 0) % ERRHASHSZ;
+	hlist_for_each_entry(c, &hash_errmap[bucket], list) {
+		if (c->namelen == len && !memcmp(c->name, errstr, len)) {
+			errno = c->val;
+			break;
+		}
+	}
+
+	if (errno == 0) {
+		/* TODO: if error isn't found, add it dynamically */
+		errstr[len] = 0;
+		pr_err("%s: server reported unknown error %s\n",
+		       __func__, errstr);
+		errno = ESERVERFAULT;
+	}
+
+	return -errno;
+}
+EXPORT_SYMBOL(p9_errstr2errno);

addons/9p/src/3.10.108/fid.c

@@ -0,0 +1,306 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_add - add a fid to a dentry
+ * @dentry: dentry that the fid is being added to
+ * @fid: fid to add
+ *
+ */
+
+static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid)
+{
+	hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata);
+}
+
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
+{
+	spin_lock(&dentry->d_lock);
+	__add_fid(dentry, fid);
+	spin_unlock(&dentry->d_lock);
+}
+
+/**
+ * v9fs_fid_find - retrieve a fid that belongs to the specified uid
+ * @dentry: dentry to look for fid in
+ * @uid: return fid that belongs to the specified user
+ * @any: if non-zero, return any fid associated with the dentry
+ *
+ */
+
+static struct p9_fid *v9fs_fid_find(struct dentry *dentry, kuid_t uid, int any)
+{
+	struct p9_fid *fid, *ret;
+
+	p9_debug(P9_DEBUG_VFS, " dentry: %s (%p) uid %d any %d\n",
+		 dentry->d_name.name, dentry, from_kuid(&init_user_ns, uid),
+		 any);
+	ret = NULL;
+	/* we'll recheck under lock if there's anything to look in */
+	if (dentry->d_fsdata) {
+		struct hlist_head *h = (struct hlist_head *)&dentry->d_fsdata;
+		spin_lock(&dentry->d_lock);
+		hlist_for_each_entry(fid, h, dlist) {
+			if (any || uid_eq(fid->uid, uid)) {
+				ret = fid;
+				break;
+			}
+		}
+		spin_unlock(&dentry->d_lock);
+	}
+
+	return ret;
+}
+
+/*
+ * We need to hold v9ses->rename_sem as long as we hold references
+ * to returned path array. Array element contain pointers to
+ * dentry names.
+ */
+static int build_path_from_dentry(struct v9fs_session_info *v9ses,
+				  struct dentry *dentry, char ***names)
+{
+	int n = 0, i;
+	char **wnames;
+	struct dentry *ds;
+
+	for (ds = dentry; !IS_ROOT(ds); ds = ds->d_parent)
+		n++;
+
+	wnames = kmalloc(sizeof(char *) * n, GFP_KERNEL);
+	if (!wnames)
+		goto err_out;
+
+	for (ds = dentry, i = (n-1); i >= 0; i--, ds = ds->d_parent)
+		wnames[i] = (char  *)ds->d_name.name;
+
+	*names = wnames;
+	return n;
+err_out:
+	return -ENOMEM;
+}
+
+static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
+					       kuid_t uid, int any)
+{
+	struct dentry *ds;
+	char **wnames, *uname;
+	int i, n, l, clone, access;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid, *old_fid = NULL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	access = v9ses->flags & V9FS_ACCESS_MASK;
+	fid = v9fs_fid_find(dentry, uid, any);
+	if (fid)
+		return fid;
+	/*
+	 * we don't have a matching fid. To do a TWALK we need
+	 * parent fid. We need to prevent rename when we want to
+	 * look at the parent.
+	 */
+	down_read(&v9ses->rename_sem);
+	ds = dentry->d_parent;
+	fid = v9fs_fid_find(ds, uid, any);
+	if (fid) {
+		/* Found the parent fid do a lookup with that */
+		fid = p9_client_walk(fid, 1, (char **)&dentry->d_name.name, 1);
+		goto fid_out;
+	}
+	up_read(&v9ses->rename_sem);
+
+	/* start from the root and try to do a lookup */
+	fid = v9fs_fid_find(dentry->d_sb->s_root, uid, any);
+	if (!fid) {
+		/* the user is not attached to the fs yet */
+		if (access == V9FS_ACCESS_SINGLE)
+			return ERR_PTR(-EPERM);
+
+		if (v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses))
+				uname = NULL;
+		else
+			uname = v9ses->uname;
+
+		fid = p9_client_attach(v9ses->clnt, NULL, uname, uid,
+				       v9ses->aname);
+		if (IS_ERR(fid))
+			return fid;
+
+		v9fs_fid_add(dentry->d_sb->s_root, fid);
+	}
+	/* If we are root ourself just return that */
+	if (dentry->d_sb->s_root == dentry)
+		return fid;
+	/*
+	 * Do a multipath walk with attached root.
+	 * When walking parent we need to make sure we
+	 * don't have a parallel rename happening
+	 */
+	down_read(&v9ses->rename_sem);
+	n  = build_path_from_dentry(v9ses, dentry, &wnames);
+	if (n < 0) {
+		fid = ERR_PTR(n);
+		goto err_out;
+	}
+	clone = 1;
+	i = 0;
+	while (i < n) {
+		l = min(n - i, P9_MAXWELEM);
+		/*
+		 * We need to hold rename lock when doing a multipath
+		 * walk to ensure none of the patch component change
+		 */
+		fid = p9_client_walk(fid, l, &wnames[i], clone);
+		if (IS_ERR(fid)) {
+			if (old_fid) {
+				/*
+				 * If we fail, clunk fid which are mapping
+				 * to path component and not the last component
+				 * of the path.
+				 */
+				p9_client_clunk(old_fid);
+			}
+			kfree(wnames);
+			goto err_out;
+		}
+		old_fid = fid;
+		i += l;
+		clone = 0;
+	}
+	kfree(wnames);
+fid_out:
+	if (!IS_ERR(fid)) {
+		spin_lock(&dentry->d_lock);
+		if (d_unhashed(dentry)) {
+			spin_unlock(&dentry->d_lock);
+			p9_client_clunk(fid);
+			fid = ERR_PTR(-ENOENT);
+		} else {
+			__add_fid(dentry, fid);
+			spin_unlock(&dentry->d_lock);
+		}
+	}
+err_out:
+	up_read(&v9ses->rename_sem);
+	return fid;
+}
+
+/**
+ * v9fs_fid_lookup - lookup for a fid, try to walk if not found
+ * @dentry: dentry to look for fid in
+ *
+ * Look for a fid in the specified dentry for the current user.
+ * If no fid is found, try to create one walking from a fid from the parent
+ * dentry (if it has one), or the root dentry. If the user haven't accessed
+ * the fs yet, attach now and walk from the root.
+ */
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
+{
+	kuid_t uid;
+	int  any, access;
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	access = v9ses->flags & V9FS_ACCESS_MASK;
+	switch (access) {
+	case V9FS_ACCESS_SINGLE:
+	case V9FS_ACCESS_USER:
+	case V9FS_ACCESS_CLIENT:
+		uid = current_fsuid();
+		any = 0;
+		break;
+
+	case V9FS_ACCESS_ANY:
+		uid = v9ses->uid;
+		any = 1;
+		break;
+
+	default:
+		uid = INVALID_UID;
+		any = 0;
+		break;
+	}
+	return v9fs_fid_lookup_with_uid(dentry, uid, any);
+}
+
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
+{
+	struct p9_fid *fid, *ret;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return fid;
+
+	ret = p9_client_walk(fid, 0, NULL, 1);
+	return ret;
+}
+
+static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, kuid_t uid)
+{
+	struct p9_fid *fid, *ret;
+
+	fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
+	if (IS_ERR(fid))
+		return fid;
+
+	ret = p9_client_walk(fid, 0, NULL, 1);
+	return ret;
+}
+
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
+{
+	int err;
+	struct p9_fid *fid;
+
+	fid = v9fs_fid_clone_with_uid(dentry, GLOBAL_ROOT_UID);
+	if (IS_ERR(fid))
+		goto error_out;
+	/*
+	 * writeback fid will only be used to write back the
+	 * dirty pages. We always request for the open fid in read-write
+	 * mode so that a partial page write which result in page
+	 * read can work.
+	 */
+	err = p9_client_open(fid, O_RDWR);
+	if (err < 0) {
+		p9_client_clunk(fid);
+		fid = ERR_PTR(err);
+		goto error_out;
+	}
+error_out:
+	return fid;
+}

addons/9p/src/3.10.108/fid.h

@@ -0,0 +1,30 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_FID_H
+#define FS_9P_FID_H
+#include <linux/list.h>
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
+#endif

addons/9p/src/3.10.108/mod.c

@@ -0,0 +1,201 @@
+/*
+ *  net/9p/9p.c
+ *
+ *  9P entry point
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/moduleparam.h>
+#include <net/9p/9p.h>
+#include <linux/fs.h>
+#include <linux/parser.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_NET_9P_DEBUG
+unsigned int p9_debug_level = 0;	/* feature-rific global debug level  */
+EXPORT_SYMBOL(p9_debug_level);
+module_param_named(debug, p9_debug_level, uint, 0);
+MODULE_PARM_DESC(debug, "9P debugging level");
+
+void _p9_debug(enum p9_debug_flags level, const char *func,
+		const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	if ((p9_debug_level & level) != level)
+		return;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	if (level == P9_DEBUG_9P)
+		pr_notice("(%8.8d) %pV", task_pid_nr(current), &vaf);
+	else
+		pr_notice("-- %s (%d): %pV", func, task_pid_nr(current), &vaf);
+
+	va_end(args);
+}
+EXPORT_SYMBOL(_p9_debug);
+#endif
+
+/*
+ * Dynamic Transport Registration Routines
+ *
+ */
+
+static DEFINE_SPINLOCK(v9fs_trans_lock);
+static LIST_HEAD(v9fs_trans_list);
+
+/**
+ * v9fs_register_trans - register a new transport with 9p
+ * @m: structure describing the transport module and entry points
+ *
+ */
+void v9fs_register_trans(struct p9_trans_module *m)
+{
+	spin_lock(&v9fs_trans_lock);
+	list_add_tail(&m->list, &v9fs_trans_list);
+	spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_register_trans);
+
+/**
+ * v9fs_unregister_trans - unregister a 9p transport
+ * @m: the transport to remove
+ *
+ */
+void v9fs_unregister_trans(struct p9_trans_module *m)
+{
+	spin_lock(&v9fs_trans_lock);
+	list_del_init(&m->list);
+	spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_unregister_trans);
+
+/**
+ * v9fs_get_trans_by_name - get transport with the matching name
+ * @name: string identifying transport
+ *
+ */
+struct p9_trans_module *v9fs_get_trans_by_name(char *s)
+{
+	struct p9_trans_module *t, *found = NULL;
+
+	spin_lock(&v9fs_trans_lock);
+
+	list_for_each_entry(t, &v9fs_trans_list, list)
+		if (strcmp(t->name, s) == 0 &&
+		    try_module_get(t->owner)) {
+			found = t;
+			break;
+		}
+
+	spin_unlock(&v9fs_trans_lock);
+	return found;
+}
+EXPORT_SYMBOL(v9fs_get_trans_by_name);
+
+/**
+ * v9fs_get_default_trans - get the default transport
+ *
+ */
+
+struct p9_trans_module *v9fs_get_default_trans(void)
+{
+	struct p9_trans_module *t, *found = NULL;
+
+	spin_lock(&v9fs_trans_lock);
+
+	list_for_each_entry(t, &v9fs_trans_list, list)
+		if (t->def && try_module_get(t->owner)) {
+			found = t;
+			break;
+		}
+
+	if (!found)
+		list_for_each_entry(t, &v9fs_trans_list, list)
+			if (try_module_get(t->owner)) {
+				found = t;
+				break;
+			}
+
+	spin_unlock(&v9fs_trans_lock);
+	return found;
+}
+EXPORT_SYMBOL(v9fs_get_default_trans);
+
+/**
+ * v9fs_put_trans - put trans
+ * @m: transport to put
+ *
+ */
+void v9fs_put_trans(struct p9_trans_module *m)
+{
+	if (m)
+		module_put(m->owner);
+}
+
+/**
+ * init_p9 - Initialize module
+ *
+ */
+static int __init init_p9(void)
+{
+	int ret = 0;
+
+	p9_error_init();
+	pr_info("Installing 9P2000 support\n");
+	p9_trans_fd_init();
+
+	return ret;
+}
+
+/**
+ * exit_p9 - shutdown module
+ *
+ */
+
+static void __exit exit_p9(void)
+{
+	pr_info("Unloading 9P2000 support\n");
+
+	p9_trans_fd_exit();
+}
+
+module_init(init_p9)
+module_exit(exit_p9)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");

addons/9p/src/3.10.108/protocol.c

@@ -0,0 +1,636 @@
+/*
+ * net/9p/protocol.c
+ *
+ * 9P Protocol Support Code
+ *
+ *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ *  Copyright (C) 2008 by IBM, Corp.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include "protocol.h"
+
+#include <trace/events/9p.h>
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+
+void p9stat_free(struct p9_wstat *stbuf)
+{
+	kfree(stbuf->name);
+	kfree(stbuf->uid);
+	kfree(stbuf->gid);
+	kfree(stbuf->muid);
+	kfree(stbuf->extension);
+}
+EXPORT_SYMBOL(p9stat_free);
+
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
+{
+	size_t len = min(pdu->size - pdu->offset, size);
+	memcpy(data, &pdu->sdata[pdu->offset], len);
+	pdu->offset += len;
+	return size - len;
+}
+
+static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
+{
+	size_t len = min(pdu->capacity - pdu->size, size);
+	memcpy(&pdu->sdata[pdu->size], data, len);
+	pdu->size += len;
+	return size - len;
+}
+
+static size_t
+pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size)
+{
+	size_t len = min(pdu->capacity - pdu->size, size);
+	if (copy_from_user(&pdu->sdata[pdu->size], udata, len))
+		len = 0;
+
+	pdu->size += len;
+	return size - len;
+}
+
+/*
+	b - int8_t
+	w - int16_t
+	d - int32_t
+	q - int64_t
+	s - string
+	u - numeric uid
+	g - numeric gid
+	S - stat
+	Q - qid
+	D - data blob (int32_t size followed by void *, results are not freed)
+	T - array of strings (int16_t count, followed by strings)
+	R - array of qids (int16_t count, followed by qids)
+	A - stat for 9p2000.L (p9_stat_dotl)
+	? - if optional = 1, continue parsing
+*/
+
+static int
+p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
+{
+	const char *ptr;
+	int errcode = 0;
+
+	for (ptr = fmt; *ptr; ptr++) {
+		switch (*ptr) {
+		case 'b':{
+				int8_t *val = va_arg(ap, int8_t *);
+				if (pdu_read(pdu, val, sizeof(*val))) {
+					errcode = -EFAULT;
+					break;
+				}
+			}
+			break;
+		case 'w':{
+				int16_t *val = va_arg(ap, int16_t *);
+				__le16 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le16_to_cpu(le_val);
+			}
+			break;
+		case 'd':{
+				int32_t *val = va_arg(ap, int32_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le32_to_cpu(le_val);
+			}
+			break;
+		case 'q':{
+				int64_t *val = va_arg(ap, int64_t *);
+				__le64 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le64_to_cpu(le_val);
+			}
+			break;
+		case 's':{
+				char **sptr = va_arg(ap, char **);
+				uint16_t len;
+
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", &len);
+				if (errcode)
+					break;
+
+				*sptr = kmalloc(len + 1, GFP_NOFS);
+				if (*sptr == NULL) {
+					errcode = -EFAULT;
+					break;
+				}
+				if (pdu_read(pdu, *sptr, len)) {
+					errcode = -EFAULT;
+					kfree(*sptr);
+					*sptr = NULL;
+				} else
+					(*sptr)[len] = 0;
+			}
+			break;
+		case 'u': {
+				kuid_t *uid = va_arg(ap, kuid_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*uid = make_kuid(&init_user_ns,
+						 le32_to_cpu(le_val));
+			} break;
+		case 'g': {
+				kgid_t *gid = va_arg(ap, kgid_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*gid = make_kgid(&init_user_ns,
+						 le32_to_cpu(le_val));
+			} break;
+		case 'Q':{
+				struct p9_qid *qid =
+				    va_arg(ap, struct p9_qid *);
+
+				errcode = p9pdu_readf(pdu, proto_version, "bdq",
+						      &qid->type, &qid->version,
+						      &qid->path);
+			}
+			break;
+		case 'S':{
+				struct p9_wstat *stbuf =
+				    va_arg(ap, struct p9_wstat *);
+
+				memset(stbuf, 0, sizeof(struct p9_wstat));
+				stbuf->n_uid = stbuf->n_muid = INVALID_UID;
+				stbuf->n_gid = INVALID_GID;
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version,
+						"wwdQdddqssss?sugu",
+						&stbuf->size, &stbuf->type,
+						&stbuf->dev, &stbuf->qid,
+						&stbuf->mode, &stbuf->atime,
+						&stbuf->mtime, &stbuf->length,
+						&stbuf->name, &stbuf->uid,
+						&stbuf->gid, &stbuf->muid,
+						&stbuf->extension,
+						&stbuf->n_uid, &stbuf->n_gid,
+						&stbuf->n_muid);
+				if (errcode)
+					p9stat_free(stbuf);
+			}
+			break;
+		case 'D':{
+				uint32_t *count = va_arg(ap, uint32_t *);
+				void **data = va_arg(ap, void **);
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version, "d", count);
+				if (!errcode) {
+					*count =
+					    min_t(uint32_t, *count,
+						  pdu->size - pdu->offset);
+					*data = &pdu->sdata[pdu->offset];
+				}
+			}
+			break;
+		case 'T':{
+				uint16_t *nwname = va_arg(ap, uint16_t *);
+				char ***wnames = va_arg(ap, char ***);
+
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", nwname);
+				if (!errcode) {
+					*wnames =
+					    kmalloc(sizeof(char *) * *nwname,
+						    GFP_NOFS);
+					if (!*wnames)
+						errcode = -ENOMEM;
+				}
+
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < *nwname; i++) {
+						errcode =
+						    p9pdu_readf(pdu,
+								proto_version,
+								"s",
+								&(*wnames)[i]);
+						if (errcode)
+							break;
+					}
+				}
+
+				if (errcode) {
+					if (*wnames) {
+						int i;
+
+						for (i = 0; i < *nwname; i++)
+							kfree((*wnames)[i]);
+					}
+					kfree(*wnames);
+					*wnames = NULL;
+				}
+			}
+			break;
+		case 'R':{
+				int16_t *nwqid = va_arg(ap, int16_t *);
+				struct p9_qid **wqids =
+				    va_arg(ap, struct p9_qid **);
+
+				*wqids = NULL;
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version, "w", nwqid);
+				if (!errcode) {
+					*wqids =
+					    kmalloc(*nwqid *
+						    sizeof(struct p9_qid),
+						    GFP_NOFS);
+					if (*wqids == NULL)
+						errcode = -ENOMEM;
+				}
+
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < *nwqid; i++) {
+						errcode =
+						    p9pdu_readf(pdu,
+								proto_version,
+								"Q",
+								&(*wqids)[i]);
+						if (errcode)
+							break;
+					}
+				}
+
+				if (errcode) {
+					kfree(*wqids);
+					*wqids = NULL;
+				}
+			}
+			break;
+		case 'A': {
+				struct p9_stat_dotl *stbuf =
+				    va_arg(ap, struct p9_stat_dotl *);
+
+				memset(stbuf, 0, sizeof(struct p9_stat_dotl));
+				errcode =
+				    p9pdu_readf(pdu, proto_version,
+					"qQdugqqqqqqqqqqqqqqq",
+					&stbuf->st_result_mask,
+					&stbuf->qid,
+					&stbuf->st_mode,
+					&stbuf->st_uid, &stbuf->st_gid,
+					&stbuf->st_nlink,
+					&stbuf->st_rdev, &stbuf->st_size,
+					&stbuf->st_blksize, &stbuf->st_blocks,
+					&stbuf->st_atime_sec,
+					&stbuf->st_atime_nsec,
+					&stbuf->st_mtime_sec,
+					&stbuf->st_mtime_nsec,
+					&stbuf->st_ctime_sec,
+					&stbuf->st_ctime_nsec,
+					&stbuf->st_btime_sec,
+					&stbuf->st_btime_nsec,
+					&stbuf->st_gen,
+					&stbuf->st_data_version);
+			}
+			break;
+		case '?':
+			if ((proto_version != p9_proto_2000u) &&
+				(proto_version != p9_proto_2000L))
+				return 0;
+			break;
+		default:
+			BUG();
+			break;
+		}
+
+		if (errcode)
+			break;
+	}
+
+	return errcode;
+}
+
+int
+p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
+{
+	const char *ptr;
+	int errcode = 0;
+
+	for (ptr = fmt; *ptr; ptr++) {
+		switch (*ptr) {
+		case 'b':{
+				int8_t val = va_arg(ap, int);
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'w':{
+				__le16 val = cpu_to_le16(va_arg(ap, int));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'd':{
+				__le32 val = cpu_to_le32(va_arg(ap, int32_t));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'q':{
+				__le64 val = cpu_to_le64(va_arg(ap, int64_t));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 's':{
+				const char *sptr = va_arg(ap, const char *);
+				uint16_t len = 0;
+				if (sptr)
+					len = min_t(size_t, strlen(sptr),
+								USHRT_MAX);
+
+				errcode = p9pdu_writef(pdu, proto_version,
+								"w", len);
+				if (!errcode && pdu_write(pdu, sptr, len))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'u': {
+				kuid_t uid = va_arg(ap, kuid_t);
+				__le32 val = cpu_to_le32(
+						from_kuid(&init_user_ns, uid));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			} break;
+		case 'g': {
+				kgid_t gid = va_arg(ap, kgid_t);
+				__le32 val = cpu_to_le32(
+						from_kgid(&init_user_ns, gid));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			} break;
+		case 'Q':{
+				const struct p9_qid *qid =
+				    va_arg(ap, const struct p9_qid *);
+				errcode =
+				    p9pdu_writef(pdu, proto_version, "bdq",
+						 qid->type, qid->version,
+						 qid->path);
+			} break;
+		case 'S':{
+				const struct p9_wstat *stbuf =
+				    va_arg(ap, const struct p9_wstat *);
+				errcode =
+				    p9pdu_writef(pdu, proto_version,
+						 "wwdQdddqssss?sugu",
+						 stbuf->size, stbuf->type,
+						 stbuf->dev, &stbuf->qid,
+						 stbuf->mode, stbuf->atime,
+						 stbuf->mtime, stbuf->length,
+						 stbuf->name, stbuf->uid,
+						 stbuf->gid, stbuf->muid,
+						 stbuf->extension, stbuf->n_uid,
+						 stbuf->n_gid, stbuf->n_muid);
+			} break;
+		case 'D':{
+				uint32_t count = va_arg(ap, uint32_t);
+				const void *data = va_arg(ap, const void *);
+
+				errcode = p9pdu_writef(pdu, proto_version, "d",
+									count);
+				if (!errcode && pdu_write(pdu, data, count))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'U':{
+				int32_t count = va_arg(ap, int32_t);
+				const char __user *udata =
+						va_arg(ap, const void __user *);
+				errcode = p9pdu_writef(pdu, proto_version, "d",
+									count);
+				if (!errcode && pdu_write_u(pdu, udata, count))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'T':{
+				uint16_t nwname = va_arg(ap, int);
+				const char **wnames = va_arg(ap, const char **);
+
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwname);
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < nwname; i++) {
+						errcode =
+						    p9pdu_writef(pdu,
+								proto_version,
+								 "s",
+								 wnames[i]);
+						if (errcode)
+							break;
+					}
+				}
+			}
+			break;
+		case 'R':{
+				int16_t nwqid = va_arg(ap, int);
+				struct p9_qid *wqids =
+				    va_arg(ap, struct p9_qid *);
+
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwqid);
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < nwqid; i++) {
+						errcode =
+						    p9pdu_writef(pdu,
+								proto_version,
+								 "Q",
+								 &wqids[i]);
+						if (errcode)
+							break;
+					}
+				}
+			}
+			break;
+		case 'I':{
+				struct p9_iattr_dotl *p9attr = va_arg(ap,
+							struct p9_iattr_dotl *);
+
+				errcode = p9pdu_writef(pdu, proto_version,
+							"ddugqqqqq",
+							p9attr->valid,
+							p9attr->mode,
+							p9attr->uid,
+							p9attr->gid,
+							p9attr->size,
+							p9attr->atime_sec,
+							p9attr->atime_nsec,
+							p9attr->mtime_sec,
+							p9attr->mtime_nsec);
+			}
+			break;
+		case '?':
+			if ((proto_version != p9_proto_2000u) &&
+				(proto_version != p9_proto_2000L))
+				return 0;
+			break;
+		default:
+			BUG();
+			break;
+		}
+
+		if (errcode)
+			break;
+	}
+
+	return errcode;
+}
+
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
+{
+	struct p9_fcall fake_pdu;
+	int ret;
+
+	fake_pdu.size = len;
+	fake_pdu.capacity = len;
+	fake_pdu.sdata = buf;
+	fake_pdu.offset = 0;
+
+	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
+	if (ret) {
+		p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
+		trace_9p_protocol_dump(clnt, &fake_pdu);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(p9stat_read);
+
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
+{
+	pdu->id = type;
+	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
+}
+
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
+{
+	int size = pdu->size;
+	int err;
+
+	pdu->size = 0;
+	err = p9pdu_writef(pdu, 0, "d", size);
+	pdu->size = size;
+
+	trace_9p_protocol_dump(clnt, pdu);
+	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
+		 pdu->size, pdu->id, pdu->tag);
+
+	return err;
+}
+
+void p9pdu_reset(struct p9_fcall *pdu)
+{
+	pdu->offset = 0;
+	pdu->size = 0;
+}
+
+int p9dirent_read(struct p9_client *clnt, char *buf, int len,
+		  struct p9_dirent *dirent)
+{
+	struct p9_fcall fake_pdu;
+	int ret;
+	char *nameptr;
+
+	fake_pdu.size = len;
+	fake_pdu.capacity = len;
+	fake_pdu.sdata = buf;
+	fake_pdu.offset = 0;
+
+	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
+			  &dirent->d_off, &dirent->d_type, &nameptr);
+	if (ret) {
+		p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
+		trace_9p_protocol_dump(clnt, &fake_pdu);
+		goto out;
+	}
+
+	strcpy(dirent->d_name, nameptr);
+	kfree(nameptr);
+
+out:
+	return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9dirent_read);

addons/9p/src/3.10.108/protocol.h

@@ -0,0 +1,34 @@
+/*
+ * net/9p/protocol.h
+ *
+ * 9P Protocol Support Code
+ *
+ *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ *  Copyright (C) 2008 by IBM, Corp.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+int p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+								va_list ap);
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type);
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu);
+void p9pdu_reset(struct p9_fcall *pdu);
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size);

addons/9p/src/3.10.108/trans_common.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <linux/scatterlist.h>
+#include "trans_common.h"
+
+/**
+ *  p9_release_req_pages - Release pages after the transaction.
+ */
+void p9_release_pages(struct page **pages, int nr_pages)
+{
+	int i;
+
+	for (i = 0; i < nr_pages; i++)
+		if (pages[i])
+			put_page(pages[i]);
+}
+EXPORT_SYMBOL(p9_release_pages);
+
+/**
+ * p9_nr_pages - Return number of pages needed to accommodate the payload.
+ */
+int p9_nr_pages(char *data, int len)
+{
+	unsigned long start_page, end_page;
+	start_page =  (unsigned long)data >> PAGE_SHIFT;
+	end_page = ((unsigned long)data + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	return end_page - start_page;
+}
+EXPORT_SYMBOL(p9_nr_pages);
+
+/**
+ * payload_gup - Translates user buffer into kernel pages and
+ * pins them either for read/write through get_user_pages_fast().
+ * @req: Request to be sent to server.
+ * @pdata_off: data offset into the first page after translation (gup).
+ * @pdata_len: Total length of the IO. gup may not return requested # of pages.
+ * @nr_pages: number of pages to accommodate the payload
+ * @rw: Indicates if the pages are for read or write.
+ */
+
+int p9_payload_gup(char *data, int *nr_pages, struct page **pages, int write)
+{
+	int nr_mapped_pages;
+
+	nr_mapped_pages = get_user_pages_fast((unsigned long)data,
+					      *nr_pages, write, pages);
+	if (nr_mapped_pages <= 0)
+		return nr_mapped_pages;
+
+	*nr_pages = nr_mapped_pages;
+	return 0;
+}
+EXPORT_SYMBOL(p9_payload_gup);

addons/9p/src/3.10.108/trans_common.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+void p9_release_pages(struct page **, int);
+int p9_payload_gup(char *, int *, struct page **, int);
+int p9_nr_pages(char *, int);

addons/9p/src/3.10.108/trans_rdma.c

@@ -0,0 +1,719 @@
+/*
+ * linux/fs/9p/trans_rdma.c
+ *
+ * RDMA transport layer based on the trans_fd.c implementation.
+ *
+ *  Copyright (C) 2008 by Tom Tucker <tom@opengridcomputing.com>
+ *  Copyright (C) 2006 by Russ Cox <rsc@swtch.com>
+ *  Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/in.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/kthread.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <linux/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/file.h>
+#include <linux/parser.h>
+#include <linux/semaphore.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/rdma_cm.h>
+
+#define P9_PORT			5640
+#define P9_RDMA_SQ_DEPTH	32
+#define P9_RDMA_RQ_DEPTH	32
+#define P9_RDMA_SEND_SGE	4
+#define P9_RDMA_RECV_SGE	4
+#define P9_RDMA_IRD		0
+#define P9_RDMA_ORD		0
+#define P9_RDMA_TIMEOUT		30000		/* 30 seconds */
+#define P9_RDMA_MAXSIZE		(4*4096)	/* Min SGE is 4, so we can
+						 * safely advertise a maxsize
+						 * of 64k */
+
+/**
+ * struct p9_trans_rdma - RDMA transport instance
+ *
+ * @state: tracks the transport state machine for connection setup and tear down
+ * @cm_id: The RDMA CM ID
+ * @pd: Protection Domain pointer
+ * @qp: Queue Pair pointer
+ * @cq: Completion Queue pointer
+ * @dm_mr: DMA Memory Region pointer
+ * @lkey: The local access only memory region key
+ * @timeout: Number of uSecs to wait for connection management events
+ * @sq_depth: The depth of the Send Queue
+ * @sq_sem: Semaphore for the SQ
+ * @rq_depth: The depth of the Receive Queue.
+ * @rq_count: Count of requests in the Receive Queue.
+ * @addr: The remote peer's address
+ * @req_lock: Protects the active request list
+ * @cm_done: Completion event for connection management tracking
+ */
+struct p9_trans_rdma {
+	enum {
+		P9_RDMA_INIT,
+		P9_RDMA_ADDR_RESOLVED,
+		P9_RDMA_ROUTE_RESOLVED,
+		P9_RDMA_CONNECTED,
+		P9_RDMA_FLUSHING,
+		P9_RDMA_CLOSING,
+		P9_RDMA_CLOSED,
+	} state;
+	struct rdma_cm_id *cm_id;
+	struct ib_pd *pd;
+	struct ib_qp *qp;
+	struct ib_cq *cq;
+	struct ib_mr *dma_mr;
+	u32 lkey;
+	long timeout;
+	int sq_depth;
+	struct semaphore sq_sem;
+	int rq_depth;
+	atomic_t rq_count;
+	struct sockaddr_in addr;
+	spinlock_t req_lock;
+
+	struct completion cm_done;
+};
+
+/**
+ * p9_rdma_context - Keeps track of in-process WR
+ *
+ * @wc_op: The original WR op for when the CQE completes in error.
+ * @busa: Bus address to unmap when the WR completes
+ * @req: Keeps track of requests (send)
+ * @rc: Keepts track of replies (receive)
+ */
+struct p9_rdma_req;
+struct p9_rdma_context {
+	enum ib_wc_opcode wc_op;
+	dma_addr_t busa;
+	union {
+		struct p9_req_t *req;
+		struct p9_fcall *rc;
+	};
+};
+
+/**
+ * p9_rdma_opts - Collection of mount options
+ * @port: port of connection
+ * @sq_depth: The requested depth of the SQ. This really doesn't need
+ * to be any deeper than the number of threads used in the client
+ * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth
+ * @timeout: Time to wait in msecs for CM events
+ */
+struct p9_rdma_opts {
+	short port;
+	int sq_depth;
+	int rq_depth;
+	long timeout;
+};
+
+/*
+ * Option Parsing (code inspired by NFS code)
+ */
+enum {
+	/* Options that take integer arguments */
+	Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout, Opt_err,
+};
+
+static match_table_t tokens = {
+	{Opt_port, "port=%u"},
+	{Opt_sq_depth, "sq=%u"},
+	{Opt_rq_depth, "rq=%u"},
+	{Opt_timeout, "timeout=%u"},
+	{Opt_err, NULL},
+};
+
+/**
+ * parse_opts - parse mount options into rdma options structure
+ * @params: options string passed from mount
+ * @opts: rdma transport-specific structure to parse options into
+ *
+ * Returns 0 upon success, -ERRNO upon failure
+ */
+static int parse_opts(char *params, struct p9_rdma_opts *opts)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int option;
+	char *options, *tmp_options;
+
+	opts->port = P9_PORT;
+	opts->sq_depth = P9_RDMA_SQ_DEPTH;
+	opts->rq_depth = P9_RDMA_RQ_DEPTH;
+	opts->timeout = P9_RDMA_TIMEOUT;
+
+	if (!params)
+		return 0;
+
+	tmp_options = kstrdup(params, GFP_KERNEL);
+	if (!tmp_options) {
+		p9_debug(P9_DEBUG_ERROR,
+			 "failed to allocate copy of option string\n");
+		return -ENOMEM;
+	}
+	options = tmp_options;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+		int r;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		r = match_int(&args[0], &option);
+		if (r < 0) {
+			p9_debug(P9_DEBUG_ERROR,
+				 "integer field, but no integer?\n");
+			continue;
+		}
+		switch (token) {
+		case Opt_port:
+			opts->port = option;
+			break;
+		case Opt_sq_depth:
+			opts->sq_depth = option;
+			break;
+		case Opt_rq_depth:
+			opts->rq_depth = option;
+			break;
+		case Opt_timeout:
+			opts->timeout = option;
+			break;
+		default:
+			continue;
+		}
+	}
+	/* RQ must be at least as large as the SQ */
+	opts->rq_depth = max(opts->rq_depth, opts->sq_depth);
+	kfree(tmp_options);
+	return 0;
+}
+
+static int
+p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event)
+{
+	struct p9_client *c = id->context;
+	struct p9_trans_rdma *rdma = c->trans;
+	switch (event->event) {
+	case RDMA_CM_EVENT_ADDR_RESOLVED:
+		BUG_ON(rdma->state != P9_RDMA_INIT);
+		rdma->state = P9_RDMA_ADDR_RESOLVED;
+		break;
+
+	case RDMA_CM_EVENT_ROUTE_RESOLVED:
+		BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED);
+		rdma->state = P9_RDMA_ROUTE_RESOLVED;
+		break;
+
+	case RDMA_CM_EVENT_ESTABLISHED:
+		BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED);
+		rdma->state = P9_RDMA_CONNECTED;
+		break;
+
+	case RDMA_CM_EVENT_DISCONNECTED:
+		if (rdma)
+			rdma->state = P9_RDMA_CLOSED;
+		if (c)
+			c->status = Disconnected;
+		break;
+
+	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
+		break;
+
+	case RDMA_CM_EVENT_ADDR_CHANGE:
+	case RDMA_CM_EVENT_ROUTE_ERROR:
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+	case RDMA_CM_EVENT_MULTICAST_JOIN:
+	case RDMA_CM_EVENT_MULTICAST_ERROR:
+	case RDMA_CM_EVENT_REJECTED:
+	case RDMA_CM_EVENT_CONNECT_REQUEST:
+	case RDMA_CM_EVENT_CONNECT_RESPONSE:
+	case RDMA_CM_EVENT_CONNECT_ERROR:
+	case RDMA_CM_EVENT_ADDR_ERROR:
+	case RDMA_CM_EVENT_UNREACHABLE:
+		c->status = Disconnected;
+		rdma_disconnect(rdma->cm_id);
+		break;
+	default:
+		BUG();
+	}
+	complete(&rdma->cm_done);
+	return 0;
+}
+
+static void
+handle_recv(struct p9_client *client, struct p9_trans_rdma *rdma,
+	    struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len)
+{
+	struct p9_req_t *req;
+	int err = 0;
+	int16_t tag;
+
+	req = NULL;
+	ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize,
+							 DMA_FROM_DEVICE);
+
+	if (status != IB_WC_SUCCESS)
+		goto err_out;
+
+	err = p9_parse_header(c->rc, NULL, NULL, &tag, 1);
+	if (err)
+		goto err_out;
+
+	req = p9_tag_lookup(client, tag);
+	if (!req)
+		goto err_out;
+
+	req->rc = c->rc;
+	req->status = REQ_STATUS_RCVD;
+	p9_client_cb(client, req);
+
+	return;
+
+ err_out:
+	p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", req, err, status);
+	rdma->state = P9_RDMA_FLUSHING;
+	client->status = Disconnected;
+}
+
+static void
+handle_send(struct p9_client *client, struct p9_trans_rdma *rdma,
+	    struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len)
+{
+	ib_dma_unmap_single(rdma->cm_id->device,
+			    c->busa, c->req->tc->size,
+			    DMA_TO_DEVICE);
+}
+
+static void qp_event_handler(struct ib_event *event, void *context)
+{
+	p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n",
+		 event->event, context);
+}
+
+static void cq_comp_handler(struct ib_cq *cq, void *cq_context)
+{
+	struct p9_client *client = cq_context;
+	struct p9_trans_rdma *rdma = client->trans;
+	int ret;
+	struct ib_wc wc;
+
+	ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP);
+	while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) {
+		struct p9_rdma_context *c = (void *) (unsigned long) wc.wr_id;
+
+		switch (c->wc_op) {
+		case IB_WC_RECV:
+			atomic_dec(&rdma->rq_count);
+			handle_recv(client, rdma, c, wc.status, wc.byte_len);
+			break;
+
+		case IB_WC_SEND:
+			handle_send(client, rdma, c, wc.status, wc.byte_len);
+			up(&rdma->sq_sem);
+			break;
+
+		default:
+			pr_err("unexpected completion type, c->wc_op=%d, wc.opcode=%d, status=%d\n",
+			       c->wc_op, wc.opcode, wc.status);
+			break;
+		}
+		kfree(c);
+	}
+}
+
+static void cq_event_handler(struct ib_event *e, void *v)
+{
+	p9_debug(P9_DEBUG_ERROR, "CQ event %d context %p\n", e->event, v);
+}
+
+static void rdma_destroy_trans(struct p9_trans_rdma *rdma)
+{
+	if (!rdma)
+		return;
+
+	if (rdma->dma_mr && !IS_ERR(rdma->dma_mr))
+		ib_dereg_mr(rdma->dma_mr);
+
+	if (rdma->qp && !IS_ERR(rdma->qp))
+		ib_destroy_qp(rdma->qp);
+
+	if (rdma->pd && !IS_ERR(rdma->pd))
+		ib_dealloc_pd(rdma->pd);
+
+	if (rdma->cq && !IS_ERR(rdma->cq))
+		ib_destroy_cq(rdma->cq);
+
+	if (rdma->cm_id && !IS_ERR(rdma->cm_id))
+		rdma_destroy_id(rdma->cm_id);
+
+	kfree(rdma);
+}
+
+static int
+post_recv(struct p9_client *client, struct p9_rdma_context *c)
+{
+	struct p9_trans_rdma *rdma = client->trans;
+	struct ib_recv_wr wr, *bad_wr;
+	struct ib_sge sge;
+
+	c->busa = ib_dma_map_single(rdma->cm_id->device,
+				    c->rc->sdata, client->msize,
+				    DMA_FROM_DEVICE);
+	if (ib_dma_mapping_error(rdma->cm_id->device, c->busa))
+		goto error;
+
+	sge.addr = c->busa;
+	sge.length = client->msize;
+	sge.lkey = rdma->lkey;
+
+	wr.next = NULL;
+	c->wc_op = IB_WC_RECV;
+	wr.wr_id = (unsigned long) c;
+	wr.sg_list = &sge;
+	wr.num_sge = 1;
+	return ib_post_recv(rdma->qp, &wr, &bad_wr);
+
+ error:
+	p9_debug(P9_DEBUG_ERROR, "EIO\n");
+	return -EIO;
+}
+
+static int rdma_request(struct p9_client *client, struct p9_req_t *req)
+{
+	struct p9_trans_rdma *rdma = client->trans;
+	struct ib_send_wr wr, *bad_wr;
+	struct ib_sge sge;
+	int err = 0;
+	unsigned long flags;
+	struct p9_rdma_context *c = NULL;
+	struct p9_rdma_context *rpl_context = NULL;
+
+	/* Allocate an fcall for the reply */
+	rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS);
+	if (!rpl_context) {
+		err = -ENOMEM;
+		goto err_close;
+	}
+
+	/*
+	 * If the request has a buffer, steal it, otherwise
+	 * allocate a new one.  Typically, requests should already
+	 * have receive buffers allocated and just swap them around
+	 */
+	if (!req->rc) {
+		req->rc = kmalloc(sizeof(struct p9_fcall)+client->msize,
+				  GFP_NOFS);
+		if (req->rc) {
+			req->rc->sdata = (char *) req->rc +
+						sizeof(struct p9_fcall);
+			req->rc->capacity = client->msize;
+		}
+	}
+	rpl_context->rc = req->rc;
+	if (!rpl_context->rc) {
+		err = -ENOMEM;
+		goto err_free2;
+	}
+
+	/*
+	 * Post a receive buffer for this request. We need to ensure
+	 * there is a reply buffer available for every outstanding
+	 * request. A flushed request can result in no reply for an
+	 * outstanding request, so we must keep a count to avoid
+	 * overflowing the RQ.
+	 */
+	if (atomic_inc_return(&rdma->rq_count) <= rdma->rq_depth) {
+		err = post_recv(client, rpl_context);
+		if (err)
+			goto err_free1;
+	} else
+		atomic_dec(&rdma->rq_count);
+
+	/* remove posted receive buffer from request structure */
+	req->rc = NULL;
+
+	/* Post the request */
+	c = kmalloc(sizeof *c, GFP_NOFS);
+	if (!c) {
+		err = -ENOMEM;
+		goto err_free1;
+	}
+	c->req = req;
+
+	c->busa = ib_dma_map_single(rdma->cm_id->device,
+				    c->req->tc->sdata, c->req->tc->size,
+				    DMA_TO_DEVICE);
+	if (ib_dma_mapping_error(rdma->cm_id->device, c->busa))
+		goto error;
+
+	sge.addr = c->busa;
+	sge.length = c->req->tc->size;
+	sge.lkey = rdma->lkey;
+
+	wr.next = NULL;
+	c->wc_op = IB_WC_SEND;
+	wr.wr_id = (unsigned long) c;
+	wr.opcode = IB_WR_SEND;
+	wr.send_flags = IB_SEND_SIGNALED;
+	wr.sg_list = &sge;
+	wr.num_sge = 1;
+
+	if (down_interruptible(&rdma->sq_sem))
+		goto error;
+
+	return ib_post_send(rdma->qp, &wr, &bad_wr);
+
+ error:
+	kfree(c);
+	kfree(rpl_context->rc);
+	kfree(rpl_context);
+	p9_debug(P9_DEBUG_ERROR, "EIO\n");
+	return -EIO;
+ err_free1:
+	kfree(rpl_context->rc);
+ err_free2:
+	kfree(rpl_context);
+ err_close:
+	spin_lock_irqsave(&rdma->req_lock, flags);
+	if (rdma->state < P9_RDMA_CLOSING) {
+		rdma->state = P9_RDMA_CLOSING;
+		spin_unlock_irqrestore(&rdma->req_lock, flags);
+		rdma_disconnect(rdma->cm_id);
+	} else
+		spin_unlock_irqrestore(&rdma->req_lock, flags);
+	return err;
+}
+
+static void rdma_close(struct p9_client *client)
+{
+	struct p9_trans_rdma *rdma;
+
+	if (!client)
+		return;
+
+	rdma = client->trans;
+	if (!rdma)
+		return;
+
+	client->status = Disconnected;
+	rdma_disconnect(rdma->cm_id);
+	rdma_destroy_trans(rdma);
+}
+
+/**
+ * alloc_rdma - Allocate and initialize the rdma transport structure
+ * @opts: Mount options structure
+ */
+static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts)
+{
+	struct p9_trans_rdma *rdma;
+
+	rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL);
+	if (!rdma)
+		return NULL;
+
+	rdma->sq_depth = opts->sq_depth;
+	rdma->rq_depth = opts->rq_depth;
+	rdma->timeout = opts->timeout;
+	spin_lock_init(&rdma->req_lock);
+	init_completion(&rdma->cm_done);
+	sema_init(&rdma->sq_sem, rdma->sq_depth);
+	atomic_set(&rdma->rq_count, 0);
+
+	return rdma;
+}
+
+/* its not clear to me we can do anything after send has been posted */
+static int rdma_cancel(struct p9_client *client, struct p9_req_t *req)
+{
+	return 1;
+}
+
+/**
+ * trans_create_rdma - Transport method for creating atransport instance
+ * @client: client instance
+ * @addr: IP address string
+ * @args: Mount options string
+ */
+static int
+rdma_create_trans(struct p9_client *client, const char *addr, char *args)
+{
+	int err;
+	struct p9_rdma_opts opts;
+	struct p9_trans_rdma *rdma;
+	struct rdma_conn_param conn_param;
+	struct ib_qp_init_attr qp_attr;
+	struct ib_device_attr devattr;
+
+	/* Parse the transport specific mount options */
+	err = parse_opts(args, &opts);
+	if (err < 0)
+		return err;
+
+	/* Create and initialize the RDMA transport structure */
+	rdma = alloc_rdma(&opts);
+	if (!rdma)
+		return -ENOMEM;
+
+	/* Create the RDMA CM ID */
+	rdma->cm_id = rdma_create_id(p9_cm_event_handler, client, RDMA_PS_TCP,
+				     IB_QPT_RC);
+	if (IS_ERR(rdma->cm_id))
+		goto error;
+
+	/* Associate the client with the transport */
+	client->trans = rdma;
+
+	/* Resolve the server's address */
+	rdma->addr.sin_family = AF_INET;
+	rdma->addr.sin_addr.s_addr = in_aton(addr);
+	rdma->addr.sin_port = htons(opts.port);
+	err = rdma_resolve_addr(rdma->cm_id, NULL,
+				(struct sockaddr *)&rdma->addr,
+				rdma->timeout);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_ADDR_RESOLVED))
+		goto error;
+
+	/* Resolve the route to the server */
+	err = rdma_resolve_route(rdma->cm_id, rdma->timeout);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_ROUTE_RESOLVED))
+		goto error;
+
+	/* Query the device attributes */
+	err = ib_query_device(rdma->cm_id->device, &devattr);
+	if (err)
+		goto error;
+
+	/* Create the Completion Queue */
+	rdma->cq = ib_create_cq(rdma->cm_id->device, cq_comp_handler,
+				cq_event_handler, client,
+				opts.sq_depth + opts.rq_depth + 1, 0);
+	if (IS_ERR(rdma->cq))
+		goto error;
+	ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP);
+
+	/* Create the Protection Domain */
+	rdma->pd = ib_alloc_pd(rdma->cm_id->device);
+	if (IS_ERR(rdma->pd))
+		goto error;
+
+	/* Cache the DMA lkey in the transport */
+	rdma->dma_mr = NULL;
+	if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)
+		rdma->lkey = rdma->cm_id->device->local_dma_lkey;
+	else {
+		rdma->dma_mr = ib_get_dma_mr(rdma->pd, IB_ACCESS_LOCAL_WRITE);
+		if (IS_ERR(rdma->dma_mr))
+			goto error;
+		rdma->lkey = rdma->dma_mr->lkey;
+	}
+
+	/* Create the Queue Pair */
+	memset(&qp_attr, 0, sizeof qp_attr);
+	qp_attr.event_handler = qp_event_handler;
+	qp_attr.qp_context = client;
+	qp_attr.cap.max_send_wr = opts.sq_depth;
+	qp_attr.cap.max_recv_wr = opts.rq_depth;
+	qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE;
+	qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE;
+	qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+	qp_attr.qp_type = IB_QPT_RC;
+	qp_attr.send_cq = rdma->cq;
+	qp_attr.recv_cq = rdma->cq;
+	err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr);
+	if (err)
+		goto error;
+	rdma->qp = rdma->cm_id->qp;
+
+	/* Request a connection */
+	memset(&conn_param, 0, sizeof(conn_param));
+	conn_param.private_data = NULL;
+	conn_param.private_data_len = 0;
+	conn_param.responder_resources = P9_RDMA_IRD;
+	conn_param.initiator_depth = P9_RDMA_ORD;
+	err = rdma_connect(rdma->cm_id, &conn_param);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_CONNECTED))
+		goto error;
+
+	client->status = Connected;
+
+	return 0;
+
+error:
+	rdma_destroy_trans(rdma);
+	return -ENOTCONN;
+}
+
+static struct p9_trans_module p9_rdma_trans = {
+	.name = "rdma",
+	.maxsize = P9_RDMA_MAXSIZE,
+	.def = 0,
+	.owner = THIS_MODULE,
+	.create = rdma_create_trans,
+	.close = rdma_close,
+	.request = rdma_request,
+	.cancel = rdma_cancel,
+};
+
+/**
+ * p9_trans_rdma_init - Register the 9P RDMA transport driver
+ */
+static int __init p9_trans_rdma_init(void)
+{
+	v9fs_register_trans(&p9_rdma_trans);
+	return 0;
+}
+
+static void __exit p9_trans_rdma_exit(void)
+{
+	v9fs_unregister_trans(&p9_rdma_trans);
+}
+
+module_init(p9_trans_rdma_init);
+module_exit(p9_trans_rdma_exit);
+
+MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>");
+MODULE_DESCRIPTION("RDMA Transport for 9P");
+MODULE_LICENSE("Dual BSD/GPL");

addons/9p/src/3.10.108/trans_virtio.c

@@ -0,0 +1,730 @@
+/*
+ * The Virtio 9p transport driver
+ *
+ * This is a block based transport driver based on the lguest block driver
+ * code.
+ *
+ *  Copyright (C) 2007, 2008 Eric Van Hensbergen, IBM Corporation
+ *
+ *  Based on virtio console driver
+ *  Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/in.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <linux/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/file.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <linux/parser.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <linux/scatterlist.h>
+#include <linux/swap.h>
+#include <linux/virtio.h>
+#include <linux/virtio_9p.h>
+#include "trans_common.h"
+
+#define VIRTQUEUE_NUM	128
+
+/* a single mutex to manage channel initialization and attachment */
+static DEFINE_MUTEX(virtio_9p_lock);
+static DECLARE_WAIT_QUEUE_HEAD(vp_wq);
+static atomic_t vp_pinned = ATOMIC_INIT(0);
+
+/**
+ * struct virtio_chan - per-instance transport information
+ * @initialized: whether the channel is initialized
+ * @inuse: whether the channel is in use
+ * @lock: protects multiple elements within this structure
+ * @client: client instance
+ * @vdev: virtio dev associated with this channel
+ * @vq: virtio queue associated with this channel
+ * @sg: scatter gather list which is used to pack a request (protected?)
+ *
+ * We keep all per-channel information in a structure.
+ * This structure is allocated within the devices dev->mem space.
+ * A pointer to the structure will get put in the transport private.
+ *
+ */
+
+struct virtio_chan {
+	bool inuse;
+
+	spinlock_t lock;
+
+	struct p9_client *client;
+	struct virtio_device *vdev;
+	struct virtqueue *vq;
+	int ring_bufs_avail;
+	wait_queue_head_t *vc_wq;
+	/* This is global limit. Since we don't have a global structure,
+	 * will be placing it in each channel.
+	 */
+	unsigned long p9_max_pages;
+	/* Scatterlist: can be too big for stack. */
+	struct scatterlist sg[VIRTQUEUE_NUM];
+
+	int tag_len;
+	/*
+	 * tag name to identify a mount Non-null terminated
+	 */
+	char *tag;
+
+	struct list_head chan_list;
+};
+
+static struct list_head virtio_chan_list;
+
+/* How many bytes left in this page. */
+static unsigned int rest_of_page(void *data)
+{
+	return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE);
+}
+
+/**
+ * p9_virtio_close - reclaim resources of a channel
+ * @client: client instance
+ *
+ * This reclaims a channel by freeing its resources and
+ * reseting its inuse flag.
+ *
+ */
+
+static void p9_virtio_close(struct p9_client *client)
+{
+	struct virtio_chan *chan = client->trans;
+
+	mutex_lock(&virtio_9p_lock);
+	if (chan)
+		chan->inuse = false;
+	mutex_unlock(&virtio_9p_lock);
+}
+
+/**
+ * req_done - callback which signals activity from the server
+ * @vq: virtio queue activity was received on
+ *
+ * This notifies us that the server has triggered some activity
+ * on the virtio channel - most likely a response to request we
+ * sent.  Figure out which requests now have responses and wake up
+ * those threads.
+ *
+ * Bugs: could do with some additional sanity checking, but appears to work.
+ *
+ */
+
+static void req_done(struct virtqueue *vq)
+{
+	struct virtio_chan *chan = vq->vdev->priv;
+	struct p9_fcall *rc;
+	unsigned int len;
+	struct p9_req_t *req;
+	unsigned long flags;
+
+	p9_debug(P9_DEBUG_TRANS, ": request done\n");
+
+	while (1) {
+		spin_lock_irqsave(&chan->lock, flags);
+		rc = virtqueue_get_buf(chan->vq, &len);
+		if (rc == NULL) {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			break;
+		}
+		chan->ring_bufs_avail = 1;
+		spin_unlock_irqrestore(&chan->lock, flags);
+		/* Wakeup if anyone waiting for VirtIO ring space. */
+		wake_up(chan->vc_wq);
+		p9_debug(P9_DEBUG_TRANS, ": rc %p\n", rc);
+		p9_debug(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag);
+		req = p9_tag_lookup(chan->client, rc->tag);
+		req->status = REQ_STATUS_RCVD;
+		p9_client_cb(chan->client, req);
+	}
+}
+
+/**
+ * pack_sg_list - pack a scatter gather list from a linear buffer
+ * @sg: scatter/gather list to pack into
+ * @start: which segment of the sg_list to start at
+ * @limit: maximum segment to pack data to
+ * @data: data to pack into scatter/gather list
+ * @count: amount of data to pack into the scatter/gather list
+ *
+ * sg_lists have multiple segments of various sizes.  This will pack
+ * arbitrary data into an existing scatter gather list, segmenting the
+ * data as necessary within constraints.
+ *
+ */
+
+static int pack_sg_list(struct scatterlist *sg, int start,
+			int limit, char *data, int count)
+{
+	int s;
+	int index = start;
+
+	while (count) {
+		s = rest_of_page(data);
+		if (s > count)
+			s = count;
+		BUG_ON(index > limit);
+		/* Make sure we don't terminate early. */
+		sg_unmark_end(&sg[index]);
+		sg_set_buf(&sg[index++], data, s);
+		count -= s;
+		data += s;
+	}
+	if (index-start)
+		sg_mark_end(&sg[index - 1]);
+	return index-start;
+}
+
+/* We don't currently allow canceling of virtio requests */
+static int p9_virtio_cancel(struct p9_client *client, struct p9_req_t *req)
+{
+	return 1;
+}
+
+/**
+ * pack_sg_list_p - Just like pack_sg_list. Instead of taking a buffer,
+ * this takes a list of pages.
+ * @sg: scatter/gather list to pack into
+ * @start: which segment of the sg_list to start at
+ * @pdata: a list of pages to add into sg.
+ * @nr_pages: number of pages to pack into the scatter/gather list
+ * @data: data to pack into scatter/gather list
+ * @count: amount of data to pack into the scatter/gather list
+ */
+static int
+pack_sg_list_p(struct scatterlist *sg, int start, int limit,
+	       struct page **pdata, int nr_pages, char *data, int count)
+{
+	int i = 0, s;
+	int data_off;
+	int index = start;
+
+	BUG_ON(nr_pages > (limit - start));
+	/*
+	 * if the first page doesn't start at
+	 * page boundary find the offset
+	 */
+	data_off = offset_in_page(data);
+	while (nr_pages) {
+		s = rest_of_page(data);
+		if (s > count)
+			s = count;
+		/* Make sure we don't terminate early. */
+		sg_unmark_end(&sg[index]);
+		sg_set_page(&sg[index++], pdata[i++], s, data_off);
+		data_off = 0;
+		data += s;
+		count -= s;
+		nr_pages--;
+	}
+
+	if (index-start)
+		sg_mark_end(&sg[index - 1]);
+	return index - start;
+}
+
+/**
+ * p9_virtio_request - issue a request
+ * @client: client instance issuing the request
+ * @req: request to be issued
+ *
+ */
+
+static int
+p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
+{
+	int err;
+	int in, out, out_sgs, in_sgs;
+	unsigned long flags;
+	struct virtio_chan *chan = client->trans;
+	struct scatterlist *sgs[2];
+
+	p9_debug(P9_DEBUG_TRANS, "9p debug: virtio request\n");
+
+	req->status = REQ_STATUS_SENT;
+req_retry:
+	spin_lock_irqsave(&chan->lock, flags);
+
+	out_sgs = in_sgs = 0;
+	/* Handle out VirtIO ring buffers */
+	out = pack_sg_list(chan->sg, 0,
+			   VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
+	if (out)
+		sgs[out_sgs++] = chan->sg;
+
+	in = pack_sg_list(chan->sg, out,
+			  VIRTQUEUE_NUM, req->rc->sdata, req->rc->capacity);
+	if (in)
+		sgs[out_sgs + in_sgs++] = chan->sg + out;
+
+	err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
+				GFP_ATOMIC);
+	if (err < 0) {
+		if (err == -ENOSPC) {
+			chan->ring_bufs_avail = 0;
+			spin_unlock_irqrestore(&chan->lock, flags);
+			err = wait_event_interruptible(*chan->vc_wq,
+							chan->ring_bufs_avail);
+			if (err  == -ERESTARTSYS)
+				return err;
+
+			p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n");
+			goto req_retry;
+		} else {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			p9_debug(P9_DEBUG_TRANS,
+				 "virtio rpc add_sgs returned failure\n");
+			return -EIO;
+		}
+	}
+	virtqueue_kick(chan->vq);
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
+	return 0;
+}
+
+static int p9_get_mapped_pages(struct virtio_chan *chan,
+			       struct page **pages, char *data,
+			       int nr_pages, int write, int kern_buf)
+{
+	int err;
+	if (!kern_buf) {
+		/*
+		 * We allow only p9_max_pages pinned. We wait for the
+		 * Other zc request to finish here
+		 */
+		if (atomic_read(&vp_pinned) >= chan->p9_max_pages) {
+			err = wait_event_interruptible(vp_wq,
+			      (atomic_read(&vp_pinned) < chan->p9_max_pages));
+			if (err == -ERESTARTSYS)
+				return err;
+		}
+		err = p9_payload_gup(data, &nr_pages, pages, write);
+		if (err < 0)
+			return err;
+		atomic_add(nr_pages, &vp_pinned);
+	} else {
+		/* kernel buffer, no need to pin pages */
+		int s, index = 0;
+		int count = nr_pages;
+		while (nr_pages) {
+			s = rest_of_page(data);
+			if (is_vmalloc_addr(data))
+				pages[index++] = vmalloc_to_page(data);
+			else
+				pages[index++] = kmap_to_page(data);
+			data += s;
+			nr_pages--;
+		}
+		nr_pages = count;
+	}
+	return nr_pages;
+}
+
+/**
+ * p9_virtio_zc_request - issue a zero copy request
+ * @client: client instance issuing the request
+ * @req: request to be issued
+ * @uidata: user bffer that should be ued for zero copy read
+ * @uodata: user buffer that shoud be user for zero copy write
+ * @inlen: read buffer size
+ * @olen: write buffer size
+ * @hdrlen: reader header size, This is the size of response protocol data
+ *
+ */
+static int
+p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
+		     char *uidata, char *uodata, int inlen,
+		     int outlen, int in_hdr_len, int kern_buf)
+{
+	int in, out, err, out_sgs, in_sgs;
+	unsigned long flags;
+	int in_nr_pages = 0, out_nr_pages = 0;
+	struct page **in_pages = NULL, **out_pages = NULL;
+	struct virtio_chan *chan = client->trans;
+	struct scatterlist *sgs[4];
+
+	p9_debug(P9_DEBUG_TRANS, "virtio request\n");
+
+	if (uodata) {
+		out_nr_pages = p9_nr_pages(uodata, outlen);
+		out_pages = kmalloc(sizeof(struct page *) * out_nr_pages,
+				    GFP_NOFS);
+		if (!out_pages) {
+			err = -ENOMEM;
+			goto err_out;
+		}
+		out_nr_pages = p9_get_mapped_pages(chan, out_pages, uodata,
+						   out_nr_pages, 0, kern_buf);
+		if (out_nr_pages < 0) {
+			err = out_nr_pages;
+			kfree(out_pages);
+			out_pages = NULL;
+			goto err_out;
+		}
+	}
+	if (uidata) {
+		in_nr_pages = p9_nr_pages(uidata, inlen);
+		in_pages = kmalloc(sizeof(struct page *) * in_nr_pages,
+				   GFP_NOFS);
+		if (!in_pages) {
+			err = -ENOMEM;
+			goto err_out;
+		}
+		in_nr_pages = p9_get_mapped_pages(chan, in_pages, uidata,
+						  in_nr_pages, 1, kern_buf);
+		if (in_nr_pages < 0) {
+			err = in_nr_pages;
+			kfree(in_pages);
+			in_pages = NULL;
+			goto err_out;
+		}
+	}
+	req->status = REQ_STATUS_SENT;
+req_retry_pinned:
+	spin_lock_irqsave(&chan->lock, flags);
+
+	out_sgs = in_sgs = 0;
+
+	/* out data */
+	out = pack_sg_list(chan->sg, 0,
+			   VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
+
+	if (out)
+		sgs[out_sgs++] = chan->sg;
+
+	if (out_pages) {
+		sgs[out_sgs++] = chan->sg + out;
+		out += pack_sg_list_p(chan->sg, out, VIRTQUEUE_NUM,
+				      out_pages, out_nr_pages, uodata, outlen);
+	}
+		
+	/*
+	 * Take care of in data
+	 * For example TREAD have 11.
+	 * 11 is the read/write header = PDU Header(7) + IO Size (4).
+	 * Arrange in such a way that server places header in the
+	 * alloced memory and payload onto the user buffer.
+	 */
+	in = pack_sg_list(chan->sg, out,
+			  VIRTQUEUE_NUM, req->rc->sdata, in_hdr_len);
+	if (in)
+		sgs[out_sgs + in_sgs++] = chan->sg + out;
+
+	if (in_pages) {
+		sgs[out_sgs + in_sgs++] = chan->sg + out + in;
+		in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
+				     in_pages, in_nr_pages, uidata, inlen);
+	}
+
+	BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs));
+	err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
+				GFP_ATOMIC);
+	if (err < 0) {
+		if (err == -ENOSPC) {
+			chan->ring_bufs_avail = 0;
+			spin_unlock_irqrestore(&chan->lock, flags);
+			err = wait_event_interruptible(*chan->vc_wq,
+						       chan->ring_bufs_avail);
+			if (err  == -ERESTARTSYS)
+				goto err_out;
+
+			p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n");
+			goto req_retry_pinned;
+		} else {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			p9_debug(P9_DEBUG_TRANS,
+				 "virtio rpc add_sgs returned failure\n");
+			err = -EIO;
+			goto err_out;
+		}
+	}
+	virtqueue_kick(chan->vq);
+	spin_unlock_irqrestore(&chan->lock, flags);
+	p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
+	err = wait_event_interruptible(*req->wq,
+				       req->status >= REQ_STATUS_RCVD);
+	/*
+	 * Non kernel buffers are pinned, unpin them
+	 */
+err_out:
+	if (!kern_buf) {
+		if (in_pages) {
+			p9_release_pages(in_pages, in_nr_pages);
+			atomic_sub(in_nr_pages, &vp_pinned);
+		}
+		if (out_pages) {
+			p9_release_pages(out_pages, out_nr_pages);
+			atomic_sub(out_nr_pages, &vp_pinned);
+		}
+		/* wakeup anybody waiting for slots to pin pages */
+		wake_up(&vp_wq);
+	}
+	kfree(in_pages);
+	kfree(out_pages);
+	return err;
+}
+
+static ssize_t p9_mount_tag_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct virtio_chan *chan;
+	struct virtio_device *vdev;
+
+	vdev = dev_to_virtio(dev);
+	chan = vdev->priv;
+
+	return snprintf(buf, chan->tag_len + 1, "%s", chan->tag);
+}
+
+static DEVICE_ATTR(mount_tag, 0444, p9_mount_tag_show, NULL);
+
+/**
+ * p9_virtio_probe - probe for existence of 9P virtio channels
+ * @vdev: virtio device to probe
+ *
+ * This probes for existing virtio channels.
+ *
+ */
+
+static int p9_virtio_probe(struct virtio_device *vdev)
+{
+	__u16 tag_len;
+	char *tag;
+	int err;
+	struct virtio_chan *chan;
+
+	chan = kmalloc(sizeof(struct virtio_chan), GFP_KERNEL);
+	if (!chan) {
+		pr_err("Failed to allocate virtio 9P channel\n");
+		err = -ENOMEM;
+		goto fail;
+	}
+
+	chan->vdev = vdev;
+
+	/* We expect one virtqueue, for requests. */
+	chan->vq = virtio_find_single_vq(vdev, req_done, "requests");
+	if (IS_ERR(chan->vq)) {
+		err = PTR_ERR(chan->vq);
+		goto out_free_vq;
+	}
+	chan->vq->vdev->priv = chan;
+	spin_lock_init(&chan->lock);
+
+	sg_init_table(chan->sg, VIRTQUEUE_NUM);
+
+	chan->inuse = false;
+	if (virtio_has_feature(vdev, VIRTIO_9P_MOUNT_TAG)) {
+		vdev->config->get(vdev,
+				offsetof(struct virtio_9p_config, tag_len),
+				&tag_len, sizeof(tag_len));
+	} else {
+		err = -EINVAL;
+		goto out_free_vq;
+	}
+	tag = kmalloc(tag_len, GFP_KERNEL);
+	if (!tag) {
+		err = -ENOMEM;
+		goto out_free_vq;
+	}
+	vdev->config->get(vdev, offsetof(struct virtio_9p_config, tag),
+			tag, tag_len);
+	chan->tag = tag;
+	chan->tag_len = tag_len;
+	err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
+	if (err) {
+		goto out_free_tag;
+	}
+	chan->vc_wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
+	if (!chan->vc_wq) {
+		err = -ENOMEM;
+		goto out_free_tag;
+	}
+	init_waitqueue_head(chan->vc_wq);
+	chan->ring_bufs_avail = 1;
+	/* Ceiling limit to avoid denial of service attacks */
+	chan->p9_max_pages = nr_free_buffer_pages()/4;
+
+	mutex_lock(&virtio_9p_lock);
+	list_add_tail(&chan->chan_list, &virtio_chan_list);
+	mutex_unlock(&virtio_9p_lock);
+
+	/* Let udev rules use the new mount_tag attribute. */
+	kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE);
+
+	return 0;
+
+out_free_tag:
+	kfree(tag);
+out_free_vq:
+	vdev->config->del_vqs(vdev);
+	kfree(chan);
+fail:
+	return err;
+}
+
+
+/**
+ * p9_virtio_create - allocate a new virtio channel
+ * @client: client instance invoking this transport
+ * @devname: string identifying the channel to connect to (unused)
+ * @args: args passed from sys_mount() for per-transport options (unused)
+ *
+ * This sets up a transport channel for 9p communication.  Right now
+ * we only match the first available channel, but eventually we couldlook up
+ * alternate channels by matching devname versus a virtio_config entry.
+ * We use a simple reference count mechanism to ensure that only a single
+ * mount has a channel open at a time.
+ *
+ */
+
+static int
+p9_virtio_create(struct p9_client *client, const char *devname, char *args)
+{
+	struct virtio_chan *chan;
+	int ret = -ENOENT;
+	int found = 0;
+
+	mutex_lock(&virtio_9p_lock);
+	list_for_each_entry(chan, &virtio_chan_list, chan_list) {
+		if (!strncmp(devname, chan->tag, chan->tag_len) &&
+		    strlen(devname) == chan->tag_len) {
+			if (!chan->inuse) {
+				chan->inuse = true;
+				found = 1;
+				break;
+			}
+			ret = -EBUSY;
+		}
+	}
+	mutex_unlock(&virtio_9p_lock);
+
+	if (!found) {
+		pr_err("no channels available\n");
+		return ret;
+	}
+
+	client->trans = (void *)chan;
+	client->status = Connected;
+	chan->client = client;
+
+	return 0;
+}
+
+/**
+ * p9_virtio_remove - clean up resources associated with a virtio device
+ * @vdev: virtio device to remove
+ *
+ */
+
+static void p9_virtio_remove(struct virtio_device *vdev)
+{
+	struct virtio_chan *chan = vdev->priv;
+
+	if (chan->inuse)
+		p9_virtio_close(chan->client);
+	vdev->config->del_vqs(vdev);
+
+	mutex_lock(&virtio_9p_lock);
+	list_del(&chan->chan_list);
+	mutex_unlock(&virtio_9p_lock);
+	sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
+	kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE);
+	kfree(chan->tag);
+	kfree(chan->vc_wq);
+	kfree(chan);
+
+}
+
+static struct virtio_device_id id_table[] = {
+	{ VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID },
+	{ 0 },
+};
+
+static unsigned int features[] = {
+	VIRTIO_9P_MOUNT_TAG,
+};
+
+/* The standard "struct lguest_driver": */
+static struct virtio_driver p9_virtio_drv = {
+	.feature_table  = features,
+	.feature_table_size = ARRAY_SIZE(features),
+	.driver.name    = KBUILD_MODNAME,
+	.driver.owner	= THIS_MODULE,
+	.id_table	= id_table,
+	.probe		= p9_virtio_probe,
+	.remove		= p9_virtio_remove,
+};
+
+static struct p9_trans_module p9_virtio_trans = {
+	.name = "virtio",
+	.create = p9_virtio_create,
+	.close = p9_virtio_close,
+	.request = p9_virtio_request,
+	.zc_request = p9_virtio_zc_request,
+	.cancel = p9_virtio_cancel,
+	/*
+	 * We leave one entry for input and one entry for response
+	 * headers. We also skip one more entry to accomodate, address
+	 * that are not at page boundary, that can result in an extra
+	 * page in zero copy.
+	 */
+	.maxsize = PAGE_SIZE * (VIRTQUEUE_NUM - 3),
+	.def = 0,
+	.owner = THIS_MODULE,
+};
+
+/* The standard init function */
+static int __init p9_virtio_init(void)
+{
+	INIT_LIST_HEAD(&virtio_chan_list);
+
+	v9fs_register_trans(&p9_virtio_trans);
+	return register_virtio_driver(&p9_virtio_drv);
+}
+
+static void __exit p9_virtio_cleanup(void)
+{
+	unregister_virtio_driver(&p9_virtio_drv);
+	v9fs_unregister_trans(&p9_virtio_trans);
+}
+
+module_init(p9_virtio_init);
+module_exit(p9_virtio_cleanup);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_DESCRIPTION("Virtio 9p Transport");
+MODULE_LICENSE("GPL");

addons/9p/src/3.10.108/util.c

@@ -0,0 +1,141 @@
+/*
+ *  net/9p/util.c
+ *
+ *  This file contains some helper functions
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+
+/**
+ * struct p9_idpool - per-connection accounting for tag idpool
+ * @lock: protects the pool
+ * @pool: idr to allocate tag id from
+ *
+ */
+
+struct p9_idpool {
+	spinlock_t lock;
+	struct idr pool;
+};
+
+/**
+ * p9_idpool_create - create a new per-connection id pool
+ *
+ */
+
+struct p9_idpool *p9_idpool_create(void)
+{
+	struct p9_idpool *p;
+
+	p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL);
+	if (!p)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock_init(&p->lock);
+	idr_init(&p->pool);
+
+	return p;
+}
+EXPORT_SYMBOL(p9_idpool_create);
+
+/**
+ * p9_idpool_destroy - create a new per-connection id pool
+ * @p: idpool to destroy
+ */
+
+void p9_idpool_destroy(struct p9_idpool *p)
+{
+	idr_destroy(&p->pool);
+	kfree(p);
+}
+EXPORT_SYMBOL(p9_idpool_destroy);
+
+/**
+ * p9_idpool_get - allocate numeric id from pool
+ * @p: pool to allocate from
+ *
+ * Bugs: This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+int p9_idpool_get(struct p9_idpool *p)
+{
+	int i;
+	unsigned long flags;
+
+	idr_preload(GFP_NOFS);
+	spin_lock_irqsave(&p->lock, flags);
+
+	/* no need to store exactly p, we just need something non-null */
+	i = idr_alloc(&p->pool, p, 0, 0, GFP_NOWAIT);
+
+	spin_unlock_irqrestore(&p->lock, flags);
+	idr_preload_end();
+	if (i < 0)
+		return -1;
+
+	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", i, p);
+	return i;
+}
+EXPORT_SYMBOL(p9_idpool_get);
+
+/**
+ * p9_idpool_put - release numeric id from pool
+ * @id: numeric id which is being released
+ * @p: pool to release id into
+ *
+ * Bugs: This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+void p9_idpool_put(int id, struct p9_idpool *p)
+{
+	unsigned long flags;
+
+	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", id, p);
+
+	spin_lock_irqsave(&p->lock, flags);
+	idr_remove(&p->pool, id);
+	spin_unlock_irqrestore(&p->lock, flags);
+}
+EXPORT_SYMBOL(p9_idpool_put);
+
+/**
+ * p9_idpool_check - check if the specified id is available
+ * @id: id to check
+ * @p: pool to check
+ */
+
+int p9_idpool_check(int id, struct p9_idpool *p)
+{
+	return idr_find(&p->pool, id) != NULL;
+}
+EXPORT_SYMBOL(p9_idpool_check);
+

addons/9p/src/3.10.108/v9fs.c

@@ -0,0 +1,677 @@
+/*
+ *  linux/fs/9p/v9fs.c
+ *
+ *  This file contains functions assisting in mapping VFS to 9P2000
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "cache.h"
+
+static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
+static LIST_HEAD(v9fs_sessionlist);
+struct kmem_cache *v9fs_inode_cache;
+
+/*
+ * Option Parsing (code inspired by NFS code)
+ *  NOTE: each transport will parse its own options
+ */
+
+enum {
+	/* Options that take integer arguments */
+	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
+	/* String options */
+	Opt_uname, Opt_remotename, Opt_trans, Opt_cache, Opt_cachetag,
+	/* Options that take no arguments */
+	Opt_nodevmap,
+	/* Cache options */
+	Opt_cache_loose, Opt_fscache,
+	/* Access options */
+	Opt_access, Opt_posixacl,
+	/* Error token */
+	Opt_err
+};
+
+static const match_table_t tokens = {
+	{Opt_debug, "debug=%x"},
+	{Opt_dfltuid, "dfltuid=%u"},
+	{Opt_dfltgid, "dfltgid=%u"},
+	{Opt_afid, "afid=%u"},
+	{Opt_uname, "uname=%s"},
+	{Opt_remotename, "aname=%s"},
+	{Opt_nodevmap, "nodevmap"},
+	{Opt_cache, "cache=%s"},
+	{Opt_cache_loose, "loose"},
+	{Opt_fscache, "fscache"},
+	{Opt_cachetag, "cachetag=%s"},
+	{Opt_access, "access=%s"},
+	{Opt_posixacl, "posixacl"},
+	{Opt_err, NULL}
+};
+
+/* Interpret mount options for cache mode */
+static int get_cache_mode(char *s)
+{
+	int version = -EINVAL;
+
+	if (!strcmp(s, "loose")) {
+		version = CACHE_LOOSE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: loose\n");
+	} else if (!strcmp(s, "fscache")) {
+		version = CACHE_FSCACHE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n");
+	} else if (!strcmp(s, "none")) {
+		version = CACHE_NONE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
+	} else
+		pr_info("Unknown Cache mode %s\n", s);
+	return version;
+}
+
+/**
+ * v9fs_parse_options - parse mount options into session structure
+ * @v9ses: existing v9fs session information
+ *
+ * Return 0 upon success, -ERRNO upon failure.
+ */
+
+static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
+{
+	char *options, *tmp_options;
+	substring_t args[MAX_OPT_ARGS];
+	char *p;
+	int option = 0;
+	char *s, *e;
+	int ret = 0;
+
+	/* setup defaults */
+	v9ses->afid = ~0;
+	v9ses->debug = 0;
+	v9ses->cache = CACHE_NONE;
+#ifdef CONFIG_9P_FSCACHE
+	v9ses->cachetag = NULL;
+#endif
+
+	if (!opts)
+		return 0;
+
+	tmp_options = kstrdup(opts, GFP_KERNEL);
+	if (!tmp_options) {
+		ret = -ENOMEM;
+		goto fail_option_alloc;
+	}
+	options = tmp_options;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token, r;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_debug:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->debug = option;
+#ifdef CONFIG_NET_9P_DEBUG
+			p9_debug_level = option;
+#endif
+			break;
+
+		case Opt_dfltuid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->dfltuid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(v9ses->dfltuid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "uid field, but not a uid?\n");
+				ret = -EINVAL;
+				continue;
+			}
+			break;
+		case Opt_dfltgid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->dfltgid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(v9ses->dfltgid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "gid field, but not a gid?\n");
+				ret = -EINVAL;
+				continue;
+			}
+			break;
+		case Opt_afid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->afid = option;
+			break;
+		case Opt_uname:
+			kfree(v9ses->uname);
+			v9ses->uname = match_strdup(&args[0]);
+			if (!v9ses->uname) {
+				ret = -ENOMEM;
+				goto free_and_return;
+			}
+			break;
+		case Opt_remotename:
+			kfree(v9ses->aname);
+			v9ses->aname = match_strdup(&args[0]);
+			if (!v9ses->aname) {
+				ret = -ENOMEM;
+				goto free_and_return;
+			}
+			break;
+		case Opt_nodevmap:
+			v9ses->nodev = 1;
+			break;
+		case Opt_cache_loose:
+			v9ses->cache = CACHE_LOOSE;
+			break;
+		case Opt_fscache:
+			v9ses->cache = CACHE_FSCACHE;
+			break;
+		case Opt_cachetag:
+#ifdef CONFIG_9P_FSCACHE
+			v9ses->cachetag = match_strdup(&args[0]);
+#endif
+			break;
+		case Opt_cache:
+			s = match_strdup(&args[0]);
+			if (!s) {
+				ret = -ENOMEM;
+				p9_debug(P9_DEBUG_ERROR,
+					 "problem allocating copy of cache arg\n");
+				goto free_and_return;
+			}
+			ret = get_cache_mode(s);
+			if (ret == -EINVAL) {
+				kfree(s);
+				goto free_and_return;
+			}
+
+			v9ses->cache = ret;
+			kfree(s);
+			break;
+
+		case Opt_access:
+			s = match_strdup(&args[0]);
+			if (!s) {
+				ret = -ENOMEM;
+				p9_debug(P9_DEBUG_ERROR,
+					 "problem allocating copy of access arg\n");
+				goto free_and_return;
+			}
+
+			v9ses->flags &= ~V9FS_ACCESS_MASK;
+			if (strcmp(s, "user") == 0)
+				v9ses->flags |= V9FS_ACCESS_USER;
+			else if (strcmp(s, "any") == 0)
+				v9ses->flags |= V9FS_ACCESS_ANY;
+			else if (strcmp(s, "client") == 0) {
+				v9ses->flags |= V9FS_ACCESS_CLIENT;
+			} else {
+				uid_t uid;
+				v9ses->flags |= V9FS_ACCESS_SINGLE;
+				uid = simple_strtoul(s, &e, 10);
+				if (*e != '\0') {
+					ret = -EINVAL;
+					pr_info("Unknown access argument %s\n",
+						s);
+					kfree(s);
+					goto free_and_return;
+				}
+				v9ses->uid = make_kuid(current_user_ns(), uid);
+				if (!uid_valid(v9ses->uid)) {
+					ret = -EINVAL;
+					pr_info("Uknown uid %s\n", s);
+					kfree(s);
+					goto free_and_return;
+				}
+			}
+
+			kfree(s);
+			break;
+
+		case Opt_posixacl:
+#ifdef CONFIG_9P_FS_POSIX_ACL
+			v9ses->flags |= V9FS_POSIX_ACL;
+#else
+			p9_debug(P9_DEBUG_ERROR,
+				 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
+#endif
+			break;
+
+		default:
+			continue;
+		}
+	}
+
+free_and_return:
+	kfree(tmp_options);
+fail_option_alloc:
+	return ret;
+}
+
+/**
+ * v9fs_session_init - initialize session
+ * @v9ses: session information structure
+ * @dev_name: device being mounted
+ * @data: options
+ *
+ */
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
+		  const char *dev_name, char *data)
+{
+	int retval = -EINVAL;
+	struct p9_fid *fid;
+	int rc;
+
+	v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
+	if (!v9ses->uname)
+		return ERR_PTR(-ENOMEM);
+
+	v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
+	if (!v9ses->aname) {
+		kfree(v9ses->uname);
+		return ERR_PTR(-ENOMEM);
+	}
+	init_rwsem(&v9ses->rename_sem);
+
+	rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY);
+	if (rc) {
+		kfree(v9ses->aname);
+		kfree(v9ses->uname);
+		return ERR_PTR(rc);
+	}
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_add(&v9ses->slist, &v9fs_sessionlist);
+	spin_unlock(&v9fs_sessionlist_lock);
+
+	v9ses->uid = INVALID_UID;
+	v9ses->dfltuid = V9FS_DEFUID;
+	v9ses->dfltgid = V9FS_DEFGID;
+
+	v9ses->clnt = p9_client_create(dev_name, data);
+	if (IS_ERR(v9ses->clnt)) {
+		retval = PTR_ERR(v9ses->clnt);
+		v9ses->clnt = NULL;
+		p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n");
+		goto error;
+	}
+
+	v9ses->flags = V9FS_ACCESS_USER;
+
+	if (p9_is_proto_dotl(v9ses->clnt)) {
+		v9ses->flags = V9FS_ACCESS_CLIENT;
+		v9ses->flags |= V9FS_PROTO_2000L;
+	} else if (p9_is_proto_dotu(v9ses->clnt)) {
+		v9ses->flags |= V9FS_PROTO_2000U;
+	}
+
+	rc = v9fs_parse_options(v9ses, data);
+	if (rc < 0) {
+		retval = rc;
+		goto error;
+	}
+
+	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
+
+	if (!v9fs_proto_dotl(v9ses) &&
+	    ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
+		/*
+		 * We support ACCESS_CLIENT only for dotl.
+		 * Fall back to ACCESS_USER
+		 */
+		v9ses->flags &= ~V9FS_ACCESS_MASK;
+		v9ses->flags |= V9FS_ACCESS_USER;
+	}
+	/*FIXME !! */
+	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
+	if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) &&
+		((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
+
+		v9ses->flags &= ~V9FS_ACCESS_MASK;
+		v9ses->flags |= V9FS_ACCESS_ANY;
+		v9ses->uid = INVALID_UID;
+	}
+	if (!v9fs_proto_dotl(v9ses) ||
+		!((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
+		/*
+		 * We support ACL checks on clinet only if the protocol is
+		 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
+		 */
+		v9ses->flags &= ~V9FS_ACL_MASK;
+	}
+
+	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
+							v9ses->aname);
+	if (IS_ERR(fid)) {
+		retval = PTR_ERR(fid);
+		fid = NULL;
+		p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
+		goto error;
+	}
+
+	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
+		fid->uid = v9ses->uid;
+	else
+		fid->uid = INVALID_UID;
+
+#ifdef CONFIG_9P_FSCACHE
+	/* register the session for caching */
+	v9fs_cache_session_get_cookie(v9ses);
+#endif
+
+	return fid;
+
+error:
+	bdi_destroy(&v9ses->bdi);
+	return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_session_close - shutdown a session
+ * @v9ses: session information structure
+ *
+ */
+
+void v9fs_session_close(struct v9fs_session_info *v9ses)
+{
+	if (v9ses->clnt) {
+		p9_client_destroy(v9ses->clnt);
+		v9ses->clnt = NULL;
+	}
+
+#ifdef CONFIG_9P_FSCACHE
+	if (v9ses->fscache) {
+		v9fs_cache_session_put_cookie(v9ses);
+		kfree(v9ses->cachetag);
+	}
+#endif
+	kfree(v9ses->uname);
+	kfree(v9ses->aname);
+
+	bdi_destroy(&v9ses->bdi);
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_del(&v9ses->slist);
+	spin_unlock(&v9fs_sessionlist_lock);
+}
+
+/**
+ * v9fs_session_cancel - terminate a session
+ * @v9ses: session to terminate
+ *
+ * mark transport as disconnected and cancel all pending requests.
+ */
+
+void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
+	p9_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
+	p9_client_disconnect(v9ses->clnt);
+}
+
+/**
+ * v9fs_session_begin_cancel - Begin terminate of a session
+ * @v9ses: session to terminate
+ *
+ * After this call we don't allow any request other than clunk.
+ */
+
+void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
+{
+	p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
+	p9_client_begin_disconnect(v9ses->clnt);
+}
+
+extern int v9fs_error_init(void);
+
+static struct kobject *v9fs_kobj;
+
+#ifdef CONFIG_9P_FSCACHE
+/**
+ * caches_show - list caches associated with a session
+ *
+ * Returns the size of buffer written.
+ */
+
+static ssize_t caches_show(struct kobject *kobj,
+			   struct kobj_attribute *attr,
+			   char *buf)
+{
+	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
+	struct v9fs_session_info *v9ses;
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
+		if (v9ses->cachetag) {
+			n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
+			if (n < 0) {
+				count = n;
+				break;
+			}
+
+			count += n;
+			limit -= n;
+		}
+	}
+
+	spin_unlock(&v9fs_sessionlist_lock);
+	return count;
+}
+
+static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
+#endif /* CONFIG_9P_FSCACHE */
+
+static struct attribute *v9fs_attrs[] = {
+#ifdef CONFIG_9P_FSCACHE
+	&v9fs_attr_cache.attr,
+#endif
+	NULL,
+};
+
+static struct attribute_group v9fs_attr_group = {
+	.attrs = v9fs_attrs,
+};
+
+/**
+ * v9fs_sysfs_init - Initialize the v9fs sysfs interface
+ *
+ */
+
+static int v9fs_sysfs_init(void)
+{
+	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
+	if (!v9fs_kobj)
+		return -ENOMEM;
+
+	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
+		kobject_put(v9fs_kobj);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
+ *
+ */
+
+static void v9fs_sysfs_cleanup(void)
+{
+	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
+	kobject_put(v9fs_kobj);
+}
+
+static void v9fs_inode_init_once(void *foo)
+{
+	struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
+#ifdef CONFIG_9P_FSCACHE
+	v9inode->fscache = NULL;
+#endif
+	memset(&v9inode->qid, 0, sizeof(v9inode->qid));
+	inode_init_once(&v9inode->vfs_inode);
+}
+
+/**
+ * v9fs_init_inode_cache - initialize a cache for 9P
+ * Returns 0 on success.
+ */
+static int v9fs_init_inode_cache(void)
+{
+	v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache",
+					  sizeof(struct v9fs_inode),
+					  0, (SLAB_RECLAIM_ACCOUNT|
+					      SLAB_MEM_SPREAD),
+					  v9fs_inode_init_once);
+	if (!v9fs_inode_cache)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/**
+ * v9fs_destroy_inode_cache - destroy the cache of 9P inode
+ *
+ */
+static void v9fs_destroy_inode_cache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(v9fs_inode_cache);
+}
+
+static int v9fs_cache_register(void)
+{
+	int ret;
+	ret = v9fs_init_inode_cache();
+	if (ret < 0)
+		return ret;
+#ifdef CONFIG_9P_FSCACHE
+	return fscache_register_netfs(&v9fs_cache_netfs);
+#else
+	return ret;
+#endif
+}
+
+static void v9fs_cache_unregister(void)
+{
+	v9fs_destroy_inode_cache();
+#ifdef CONFIG_9P_FSCACHE
+	fscache_unregister_netfs(&v9fs_cache_netfs);
+#endif
+}
+
+/**
+ * init_v9fs - Initialize module
+ *
+ */
+
+static int __init init_v9fs(void)
+{
+	int err;
+	pr_info("Installing v9fs 9p2000 file system support\n");
+	/* TODO: Setup list of registered trasnport modules */
+
+	err = v9fs_cache_register();
+	if (err < 0) {
+		pr_err("Failed to register v9fs for caching\n");
+		return err;
+	}
+
+	err = v9fs_sysfs_init();
+	if (err < 0) {
+		pr_err("Failed to register with sysfs\n");
+		goto out_cache;
+	}
+	err = register_filesystem(&v9fs_fs_type);
+	if (err < 0) {
+		pr_err("Failed to register filesystem\n");
+		goto out_sysfs_cleanup;
+	}
+
+	return 0;
+
+out_sysfs_cleanup:
+	v9fs_sysfs_cleanup();
+
+out_cache:
+	v9fs_cache_unregister();
+
+	return err;
+}
+
+/**
+ * exit_v9fs - shutdown module
+ *
+ */
+
+static void __exit exit_v9fs(void)
+{
+	v9fs_sysfs_cleanup();
+	v9fs_cache_unregister();
+	unregister_filesystem(&v9fs_fs_type);
+}
+
+module_init(init_v9fs)
+module_exit(exit_v9fs)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");

addons/9p/src/3.10.108/v9fs.h

@@ -0,0 +1,227 @@
+/*
+ * V9FS definitions.
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_V9FS_H
+#define FS_9P_V9FS_H
+
+#include <linux/backing-dev.h>
+
+/**
+ * enum p9_session_flags - option flags for each 9P session
+ * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
+ * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
+ * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
+ * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
+ * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
+ * @V9FS_ACCESS_ANY: use a single attach for all users
+ * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
+ * @V9FS_POSIX_ACL: POSIX ACLs are enforced
+ *
+ * Session flags reflect options selected by users at mount time
+ */
+#define	V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
+			 V9FS_ACCESS_USER |   \
+			 V9FS_ACCESS_CLIENT)
+#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
+#define V9FS_ACL_MASK V9FS_POSIX_ACL
+
+enum p9_session_flags {
+	V9FS_PROTO_2000U	= 0x01,
+	V9FS_PROTO_2000L	= 0x02,
+	V9FS_ACCESS_SINGLE	= 0x04,
+	V9FS_ACCESS_USER	= 0x08,
+	V9FS_ACCESS_CLIENT	= 0x10,
+	V9FS_POSIX_ACL		= 0x20
+};
+
+/* possible values of ->cache */
+/**
+ * enum p9_cache_modes - user specified cache preferences
+ * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
+ * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
+ *
+ * eventually support loose, tight, time, session, default always none
+ */
+
+enum p9_cache_modes {
+	CACHE_NONE,
+	CACHE_LOOSE,
+	CACHE_FSCACHE,
+};
+
+/**
+ * struct v9fs_session_info - per-instance session information
+ * @flags: session options of type &p9_session_flags
+ * @nodev: set to 1 to disable device mapping
+ * @debug: debug level
+ * @afid: authentication handle
+ * @cache: cache mode of type &p9_cache_modes
+ * @cachetag: the tag of the cache associated with this session
+ * @fscache: session cookie associated with FS-Cache
+ * @options: copy of options string given by user
+ * @uname: string user name to mount hierarchy as
+ * @aname: mount specifier for remote hierarchy
+ * @maxdata: maximum data to be sent/recvd per protocol message
+ * @dfltuid: default numeric userid to mount hierarchy as
+ * @dfltgid: default numeric groupid to mount hierarchy as
+ * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
+ * @clnt: reference to 9P network client instantiated for this session
+ * @slist: reference to list of registered 9p sessions
+ *
+ * This structure holds state for each session instance established during
+ * a sys_mount() .
+ *
+ * Bugs: there seems to be a lot of state which could be condensed and/or
+ * removed.
+ */
+
+struct v9fs_session_info {
+	/* options */
+	unsigned char flags;
+	unsigned char nodev;
+	unsigned short debug;
+	unsigned int afid;
+	unsigned int cache;
+#ifdef CONFIG_9P_FSCACHE
+	char *cachetag;
+	struct fscache_cookie *fscache;
+#endif
+
+	char *uname;		/* user name to mount as */
+	char *aname;		/* name of remote hierarchy being mounted */
+	unsigned int maxdata;	/* max data for client interface */
+	kuid_t dfltuid;		/* default uid/muid for legacy support */
+	kgid_t dfltgid;		/* default gid for legacy support */
+	kuid_t uid;		/* if ACCESS_SINGLE, the uid that has access */
+	struct p9_client *clnt;	/* 9p client */
+	struct list_head slist; /* list of sessions registered with v9fs */
+	struct backing_dev_info bdi;
+	struct rw_semaphore rename_sem;
+};
+
+/* cache_validity flags */
+#define V9FS_INO_INVALID_ATTR 0x01
+
+struct v9fs_inode {
+#ifdef CONFIG_9P_FSCACHE
+	spinlock_t fscache_lock;
+	struct fscache_cookie *fscache;
+#endif
+	struct p9_qid qid;
+	unsigned int cache_validity;
+	struct p9_fid *writeback_fid;
+	struct mutex v_mutex;
+	struct inode vfs_inode;
+};
+
+static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
+{
+	return container_of(inode, struct v9fs_inode, vfs_inode);
+}
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
+									char *);
+extern void v9fs_session_close(struct v9fs_session_info *v9ses);
+extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
+extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
+extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
+			unsigned int flags);
+extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry);
+extern void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd,
+			void *p);
+extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
+					 struct p9_fid *fid,
+					 struct super_block *sb, int new);
+extern const struct inode_operations v9fs_dir_inode_operations_dotl;
+extern const struct inode_operations v9fs_file_inode_operations_dotl;
+extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
+extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
+					      struct p9_fid *fid,
+					      struct super_block *sb, int new);
+
+/* other default globals */
+#define V9FS_PORT	564
+#define V9FS_DEFUSER	"nobody"
+#define V9FS_DEFANAME	""
+#define V9FS_DEFUID	KUIDT_INIT(-2)
+#define V9FS_DEFGID	KGIDT_INIT(-2)
+
+static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
+{
+	return (inode->i_sb->s_fs_info);
+}
+
+static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
+{
+	return dentry->d_sb->s_fs_info;
+}
+
+static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_PROTO_2000U;
+}
+
+static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_PROTO_2000L;
+}
+
+/**
+ * v9fs_get_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+			struct super_block *sb)
+{
+	if (v9fs_proto_dotl(v9ses))
+		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
+	else
+		return v9fs_inode_from_fid(v9ses, fid, sb, 0);
+}
+
+/**
+ * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+			    struct super_block *sb)
+{
+	if (v9fs_proto_dotl(v9ses))
+		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
+	else
+		return v9fs_inode_from_fid(v9ses, fid, sb, 1);
+}
+
+#endif

addons/9p/src/3.10.108/v9fs_vfs.h

@@ -0,0 +1,88 @@
+/*
+ * V9FS VFS extensions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_V9FS_VFS_H
+#define FS_9P_V9FS_VFS_H
+
+/* plan9 semantics are that created files are implicitly opened.
+ * But linux semantics are that you call create, then open.
+ * the plan9 approach is superior as it provides an atomic
+ * open.
+ * we track the create fid here. When the file is opened, if fidopen is
+ * non-zero, we use the fid and can skip some steps.
+ * there may be a better way to do this, but I don't know it.
+ * one BAD way is to clunk the fid on create, then open it again:
+ * you lose the atomicity of file open
+ */
+
+/* special case:
+ * unlink calls remove, which is an implicit clunk. So we have to track
+ * that kind of thing so that we don't try to clunk a dead fid.
+ */
+#define P9_LOCK_TIMEOUT (30*HZ)
+
+extern struct file_system_type v9fs_fs_type;
+extern const struct address_space_operations v9fs_addr_operations;
+extern const struct file_operations v9fs_file_operations;
+extern const struct file_operations v9fs_file_operations_dotl;
+extern const struct file_operations v9fs_dir_operations;
+extern const struct file_operations v9fs_dir_operations_dotl;
+extern const struct dentry_operations v9fs_dentry_operations;
+extern const struct dentry_operations v9fs_cached_dentry_operations;
+extern const struct file_operations v9fs_cached_file_operations;
+extern const struct file_operations v9fs_cached_file_operations_dotl;
+extern struct kmem_cache *v9fs_inode_cache;
+
+struct inode *v9fs_alloc_inode(struct super_block *sb);
+void v9fs_destroy_inode(struct inode *inode);
+struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t);
+int v9fs_init_inode(struct v9fs_session_info *v9ses,
+		    struct inode *inode, umode_t mode, dev_t);
+void v9fs_evict_inode(struct inode *inode);
+ino_t v9fs_qid2ino(struct p9_qid *qid);
+void v9fs_stat2inode(struct p9_wstat *, struct inode *, struct super_block *);
+void v9fs_stat2inode_dotl(struct p9_stat_dotl *, struct inode *);
+int v9fs_dir_release(struct inode *inode, struct file *filp);
+int v9fs_file_open(struct inode *inode, struct file *file);
+void v9fs_inode2stat(struct inode *inode, struct p9_wstat *stat);
+int v9fs_uflags2omode(int uflags, int extended);
+
+ssize_t v9fs_file_readn(struct file *, char *, char __user *, u32, u64);
+ssize_t v9fs_fid_readn(struct p9_fid *, char *, char __user *, u32, u64);
+void v9fs_blank_wstat(struct p9_wstat *wstat);
+int v9fs_vfs_setattr_dotl(struct dentry *, struct iattr *);
+int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
+			 int datasync);
+ssize_t v9fs_file_write_internal(struct inode *, struct p9_fid *,
+				 const char __user *, size_t, loff_t *, int);
+int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode);
+int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode);
+static inline void v9fs_invalidate_inode_attr(struct inode *inode)
+{
+	struct v9fs_inode *v9inode;
+	v9inode = V9FS_I(inode);
+	v9inode->cache_validity |= V9FS_INO_INVALID_ATTR;
+	return;
+}
+
+int v9fs_open_to_dotl_flags(int flags);
+#endif

addons/9p/src/3.10.108/vfs_addr.c

@@ -0,0 +1,353 @@
+/*
+ *  linux/fs/9p/vfs_addr.c
+ *
+ * This file contians vfs address (mmap) ops for 9P2000.
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/aio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "cache.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_readpage - read an entire page in from 9P
+ *
+ * @fid: fid being read
+ * @page: structure to page
+ *
+ */
+static int v9fs_fid_readpage(struct p9_fid *fid, struct page *page)
+{
+	int retval;
+	loff_t offset;
+	char *buffer;
+	struct inode *inode;
+
+	inode = page->mapping->host;
+	p9_debug(P9_DEBUG_VFS, "\n");
+
+	BUG_ON(!PageLocked(page));
+
+	retval = v9fs_readpage_from_fscache(inode, page);
+	if (retval == 0)
+		return retval;
+
+	buffer = kmap(page);
+	offset = page_offset(page);
+
+	retval = v9fs_fid_readn(fid, buffer, NULL, PAGE_CACHE_SIZE, offset);
+	if (retval < 0) {
+		v9fs_uncache_page(inode, page);
+		goto done;
+	}
+
+	memset(buffer + retval, 0, PAGE_CACHE_SIZE - retval);
+	flush_dcache_page(page);
+	SetPageUptodate(page);
+
+	v9fs_readpage_to_fscache(inode, page);
+	retval = 0;
+
+done:
+	kunmap(page);
+	unlock_page(page);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_readpage - read an entire page in from 9P
+ *
+ * @filp: file being read
+ * @page: structure to page
+ *
+ */
+
+static int v9fs_vfs_readpage(struct file *filp, struct page *page)
+{
+	return v9fs_fid_readpage(filp->private_data, page);
+}
+
+/**
+ * v9fs_vfs_readpages - read a set of pages from 9P
+ *
+ * @filp: file being read
+ * @mapping: the address space
+ * @pages: list of pages to read
+ * @nr_pages: count of pages to read
+ *
+ */
+
+static int v9fs_vfs_readpages(struct file *filp, struct address_space *mapping,
+			     struct list_head *pages, unsigned nr_pages)
+{
+	int ret = 0;
+	struct inode *inode;
+
+	inode = mapping->host;
+	p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, filp);
+
+	ret = v9fs_readpages_from_fscache(inode, mapping, pages, &nr_pages);
+	if (ret == 0)
+		return ret;
+
+	ret = read_cache_pages(mapping, pages, (void *)v9fs_vfs_readpage, filp);
+	p9_debug(P9_DEBUG_VFS, "  = %d\n", ret);
+	return ret;
+}
+
+/**
+ * v9fs_release_page - release the private state associated with a page
+ *
+ * Returns 1 if the page can be released, false otherwise.
+ */
+
+static int v9fs_release_page(struct page *page, gfp_t gfp)
+{
+	if (PagePrivate(page))
+		return 0;
+	return v9fs_fscache_release_page(page, gfp);
+}
+
+/**
+ * v9fs_invalidate_page - Invalidate a page completely or partially
+ *
+ * @page: structure to page
+ * @offset: offset in the page
+ */
+
+static void v9fs_invalidate_page(struct page *page, unsigned long offset)
+{
+	/*
+	 * If called with zero offset, we should release
+	 * the private state assocated with the page
+	 */
+	if (offset == 0)
+		v9fs_fscache_invalidate_page(page);
+}
+
+static int v9fs_vfs_writepage_locked(struct page *page)
+{
+	char *buffer;
+	int retval, len;
+	loff_t offset, size;
+	mm_segment_t old_fs;
+	struct v9fs_inode *v9inode;
+	struct inode *inode = page->mapping->host;
+
+	v9inode = V9FS_I(inode);
+	size = i_size_read(inode);
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	set_page_writeback(page);
+
+	buffer = kmap(page);
+	offset = page_offset(page);
+
+	old_fs = get_fs();
+	set_fs(get_ds());
+	/* We should have writeback_fid always set */
+	BUG_ON(!v9inode->writeback_fid);
+
+	retval = v9fs_file_write_internal(inode,
+					  v9inode->writeback_fid,
+					  (__force const char __user *)buffer,
+					  len, &offset, 0);
+	if (retval > 0)
+		retval = 0;
+
+	set_fs(old_fs);
+	kunmap(page);
+	end_page_writeback(page);
+	return retval;
+}
+
+static int v9fs_vfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	int retval;
+
+	retval = v9fs_vfs_writepage_locked(page);
+	if (retval < 0) {
+		if (retval == -EAGAIN) {
+			redirty_page_for_writepage(wbc, page);
+			retval = 0;
+		} else {
+			SetPageError(page);
+			mapping_set_error(page->mapping, retval);
+		}
+	} else
+		retval = 0;
+
+	unlock_page(page);
+	return retval;
+}
+
+/**
+ * v9fs_launder_page - Writeback a dirty page
+ * Returns 0 on success.
+ */
+
+static int v9fs_launder_page(struct page *page)
+{
+	int retval;
+	struct inode *inode = page->mapping->host;
+
+	v9fs_fscache_wait_on_page_write(inode, page);
+	if (clear_page_dirty_for_io(page)) {
+		retval = v9fs_vfs_writepage_locked(page);
+		if (retval)
+			return retval;
+	}
+	return 0;
+}
+
+/**
+ * v9fs_direct_IO - 9P address space operation for direct I/O
+ * @rw: direction (read or write)
+ * @iocb: target I/O control block
+ * @iov: array of vectors that define I/O buffer
+ * @pos: offset in file to begin the operation
+ * @nr_segs: size of iovec array
+ *
+ * The presence of v9fs_direct_IO() in the address space ops vector
+ * allowes open() O_DIRECT flags which would have failed otherwise.
+ *
+ * In the non-cached mode, we shunt off direct read and write requests before
+ * the VFS gets them, so this method should never be called.
+ *
+ * Direct IO is not 'yet' supported in the cached mode. Hence when
+ * this routine is called through generic_file_aio_read(), the read/write fails
+ * with an error.
+ *
+ */
+static ssize_t
+v9fs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
+	       loff_t pos, unsigned long nr_segs)
+{
+	/*
+	 * FIXME
+	 * Now that we do caching with cache mode enabled, We need
+	 * to support direct IO
+	 */
+	p9_debug(P9_DEBUG_VFS, "v9fs_direct_IO: v9fs_direct_IO (%s) off/no(%lld/%lu) EINVAL\n",
+		 iocb->ki_filp->f_path.dentry->d_name.name,
+		 (long long)pos, nr_segs);
+
+	return -EINVAL;
+}
+
+static int v9fs_write_begin(struct file *filp, struct address_space *mapping,
+			    loff_t pos, unsigned len, unsigned flags,
+			    struct page **pagep, void **fsdata)
+{
+	int retval = 0;
+	struct page *page;
+	struct v9fs_inode *v9inode;
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+	struct inode *inode = mapping->host;
+
+	v9inode = V9FS_I(inode);
+start:
+	page = grab_cache_page_write_begin(mapping, index, flags);
+	if (!page) {
+		retval = -ENOMEM;
+		goto out;
+	}
+	BUG_ON(!v9inode->writeback_fid);
+	if (PageUptodate(page))
+		goto out;
+
+	if (len == PAGE_CACHE_SIZE)
+		goto out;
+
+	retval = v9fs_fid_readpage(v9inode->writeback_fid, page);
+	page_cache_release(page);
+	if (!retval)
+		goto start;
+out:
+	*pagep = page;
+	return retval;
+}
+
+static int v9fs_write_end(struct file *filp, struct address_space *mapping,
+			  loff_t pos, unsigned len, unsigned copied,
+			  struct page *page, void *fsdata)
+{
+	loff_t last_pos = pos + copied;
+	struct inode *inode = page->mapping->host;
+
+	if (unlikely(copied < len)) {
+		/*
+		 * zero out the rest of the area
+		 */
+		unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+
+		zero_user(page, from + copied, len - copied);
+		flush_dcache_page(page);
+	}
+
+	if (!PageUptodate(page))
+		SetPageUptodate(page);
+	/*
+	 * No need to use i_size_read() here, the i_size
+	 * cannot change under us because we hold the i_mutex.
+	 */
+	if (last_pos > inode->i_size) {
+		inode_add_bytes(inode, last_pos - inode->i_size);
+		i_size_write(inode, last_pos);
+	}
+	set_page_dirty(page);
+	unlock_page(page);
+	page_cache_release(page);
+
+	return copied;
+}
+
+
+const struct address_space_operations v9fs_addr_operations = {
+	.readpage = v9fs_vfs_readpage,
+	.readpages = v9fs_vfs_readpages,
+	.set_page_dirty = __set_page_dirty_nobuffers,
+	.writepage = v9fs_vfs_writepage,
+	.write_begin = v9fs_write_begin,
+	.write_end = v9fs_write_end,
+	.releasepage = v9fs_release_page,
+	.invalidatepage = v9fs_invalidate_page,
+	.launder_page = v9fs_launder_page,
+	.direct_IO = v9fs_direct_IO,
+};

addons/9p/src/3.10.108/vfs_dentry.c

@@ -0,0 +1,139 @@
+/*
+ *  linux/fs/9p/vfs_dentry.c
+ *
+ * This file contians vfs dentry ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_dentry_delete - called when dentry refcount equals 0
+ * @dentry:  dentry in question
+ *
+ * By returning 1 here we should remove cacheing of unused
+ * dentry components.
+ *
+ */
+
+static int v9fs_dentry_delete(const struct dentry *dentry)
+{
+	p9_debug(P9_DEBUG_VFS, " dentry: %s (%p)\n",
+		 dentry->d_name.name, dentry);
+
+	return 1;
+}
+
+/**
+ * v9fs_cached_dentry_delete - called when dentry refcount equals 0
+ * @dentry:  dentry in question
+ *
+ */
+static int v9fs_cached_dentry_delete(const struct dentry *dentry)
+{
+	p9_debug(P9_DEBUG_VFS, " dentry: %s (%p)\n",
+		 dentry->d_name.name, dentry);
+
+	/* Don't cache negative dentries */
+	if (!dentry->d_inode)
+		return 1;
+	return 0;
+}
+
+/**
+ * v9fs_dentry_release - called when dentry is going to be freed
+ * @dentry:  dentry that is being release
+ *
+ */
+
+static void v9fs_dentry_release(struct dentry *dentry)
+{
+	struct hlist_node *p, *n;
+	p9_debug(P9_DEBUG_VFS, " dentry: %s (%p)\n",
+		 dentry->d_name.name, dentry);
+	hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
+		p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
+	dentry->d_fsdata = NULL;
+}
+
+static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	struct p9_fid *fid;
+	struct inode *inode;
+	struct v9fs_inode *v9inode;
+
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	inode = dentry->d_inode;
+	if (!inode)
+		goto out_valid;
+
+	v9inode = V9FS_I(inode);
+	if (v9inode->cache_validity & V9FS_INO_INVALID_ATTR) {
+		int retval;
+		struct v9fs_session_info *v9ses;
+		fid = v9fs_fid_lookup(dentry);
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		v9ses = v9fs_inode2v9ses(inode);
+		if (v9fs_proto_dotl(v9ses))
+			retval = v9fs_refresh_inode_dotl(fid, inode);
+		else
+			retval = v9fs_refresh_inode(fid, inode);
+		if (retval == -ENOENT)
+			return 0;
+		if (retval < 0)
+			return retval;
+	}
+out_valid:
+	return 1;
+}
+
+const struct dentry_operations v9fs_cached_dentry_operations = {
+	.d_revalidate = v9fs_lookup_revalidate,
+	.d_weak_revalidate = v9fs_lookup_revalidate,
+	.d_delete = v9fs_cached_dentry_delete,
+	.d_release = v9fs_dentry_release,
+};
+
+const struct dentry_operations v9fs_dentry_operations = {
+	.d_delete = v9fs_dentry_delete,
+	.d_release = v9fs_dentry_release,
+};

addons/9p/src/3.10.108/vfs_dir.c

@@ -0,0 +1,269 @@
+/*
+ * linux/fs/9p/vfs_dir.c
+ *
+ * This file contains vfs directory ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * struct p9_rdir - readdir accounting
+ * @mutex: mutex protecting readdir
+ * @head: start offset of current dirread buffer
+ * @tail: end offset of current dirread buffer
+ * @buf: dirread buffer
+ *
+ * private structure for keeping track of readdir
+ * allocated on demand
+ */
+
+struct p9_rdir {
+	int head;
+	int tail;
+	uint8_t buf[];
+};
+
+/**
+ * dt_type - return file type
+ * @mistat: mistat structure
+ *
+ */
+
+static inline int dt_type(struct p9_wstat *mistat)
+{
+	unsigned long perm = mistat->mode;
+	int rettype = DT_REG;
+
+	if (perm & P9_DMDIR)
+		rettype = DT_DIR;
+	if (perm & P9_DMSYMLINK)
+		rettype = DT_LNK;
+
+	return rettype;
+}
+
+static void p9stat_init(struct p9_wstat *stbuf)
+{
+	stbuf->name  = NULL;
+	stbuf->uid   = NULL;
+	stbuf->gid   = NULL;
+	stbuf->muid  = NULL;
+	stbuf->extension = NULL;
+}
+
+/**
+ * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
+ * @filp: opened file structure
+ * @buflen: Length in bytes of buffer to allocate
+ *
+ */
+
+static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
+{
+	struct p9_fid *fid = filp->private_data;
+	if (!fid->rdir)
+		fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
+	return fid->rdir;
+}
+
+/**
+ * v9fs_dir_readdir - read a directory
+ * @filp: opened file structure
+ * @dirent: directory structure ???
+ * @filldir: function to populate directory structure ???
+ *
+ */
+
+static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	int over;
+	struct p9_wstat st;
+	int err = 0;
+	struct p9_fid *fid;
+	int buflen;
+	int reclen = 0;
+	struct p9_rdir *rdir;
+
+	p9_debug(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name);
+	fid = filp->private_data;
+
+	buflen = fid->clnt->msize - P9_IOHDRSZ;
+
+	rdir = v9fs_alloc_rdir_buf(filp, buflen);
+	if (!rdir)
+		return -ENOMEM;
+
+	while (1) {
+		if (rdir->tail == rdir->head) {
+			err = v9fs_file_readn(filp, rdir->buf, NULL,
+							buflen, filp->f_pos);
+			if (err <= 0)
+				return err;
+
+			rdir->head = 0;
+			rdir->tail = err;
+		}
+		while (rdir->head < rdir->tail) {
+			p9stat_init(&st);
+			err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
+					  rdir->tail - rdir->head, &st);
+			if (err) {
+				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
+				p9stat_free(&st);
+				return -EIO;
+			}
+			reclen = st.size+2;
+
+			over = filldir(dirent, st.name, strlen(st.name),
+			    filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st));
+
+			p9stat_free(&st);
+
+			if (over)
+				return 0;
+
+			rdir->head += reclen;
+			filp->f_pos += reclen;
+		}
+	}
+}
+
+/**
+ * v9fs_dir_readdir_dotl - read a directory
+ * @filp: opened file structure
+ * @dirent: buffer to fill dirent structures
+ * @filldir: function to populate dirent structures
+ *
+ */
+static int v9fs_dir_readdir_dotl(struct file *filp, void *dirent,
+						filldir_t filldir)
+{
+	int over;
+	int err = 0;
+	struct p9_fid *fid;
+	int buflen;
+	struct p9_rdir *rdir;
+	struct p9_dirent curdirent;
+	u64 oldoffset = 0;
+
+	p9_debug(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name);
+	fid = filp->private_data;
+
+	buflen = fid->clnt->msize - P9_READDIRHDRSZ;
+
+	rdir = v9fs_alloc_rdir_buf(filp, buflen);
+	if (!rdir)
+		return -ENOMEM;
+
+	while (1) {
+		if (rdir->tail == rdir->head) {
+			err = p9_client_readdir(fid, rdir->buf, buflen,
+						filp->f_pos);
+			if (err <= 0)
+				return err;
+
+			rdir->head = 0;
+			rdir->tail = err;
+		}
+
+		while (rdir->head < rdir->tail) {
+
+			err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
+					    rdir->tail - rdir->head,
+					    &curdirent);
+			if (err < 0) {
+				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
+				return -EIO;
+			}
+
+			/* d_off in dirent structure tracks the offset into
+			 * the next dirent in the dir. However, filldir()
+			 * expects offset into the current dirent. Hence
+			 * while calling filldir send the offset from the
+			 * previous dirent structure.
+			 */
+			over = filldir(dirent, curdirent.d_name,
+					strlen(curdirent.d_name),
+					oldoffset, v9fs_qid2ino(&curdirent.qid),
+					curdirent.d_type);
+			oldoffset = curdirent.d_off;
+
+			if (over)
+				return 0;
+
+			filp->f_pos = curdirent.d_off;
+			rdir->head += err;
+		}
+	}
+}
+
+
+/**
+ * v9fs_dir_release - close a directory
+ * @inode: inode of the directory
+ * @filp: file pointer to a directory
+ *
+ */
+
+int v9fs_dir_release(struct inode *inode, struct file *filp)
+{
+	struct p9_fid *fid;
+
+	fid = filp->private_data;
+	p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
+		 inode, filp, fid ? fid->fid : -1);
+	if (fid)
+		p9_client_clunk(fid);
+	return 0;
+}
+
+const struct file_operations v9fs_dir_operations = {
+	.read = generic_read_dir,
+	.llseek = generic_file_llseek,
+	.readdir = v9fs_dir_readdir,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+};
+
+const struct file_operations v9fs_dir_operations_dotl = {
+	.read = generic_read_dir,
+	.llseek = generic_file_llseek,
+	.readdir = v9fs_dir_readdir_dotl,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+        .fsync = v9fs_file_fsync_dotl,
+};

addons/9p/src/3.10.108/vfs_file.c

@@ -0,0 +1,790 @@
+/*
+ *  linux/fs/9p/vfs_file.c
+ *
+ * This file contians vfs file ops for 9P2000.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/list.h>
+#include <linux/pagemap.h>
+#include <linux/utsname.h>
+#include <asm/uaccess.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+#include "cache.h"
+
+static const struct vm_operations_struct v9fs_file_vm_ops;
+
+/**
+ * v9fs_file_open - open a file (or directory)
+ * @inode: inode to be opened
+ * @file: file being opened
+ *
+ */
+
+int v9fs_file_open(struct inode *inode, struct file *file)
+{
+	int err;
+	struct v9fs_inode *v9inode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	int omode;
+
+	p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
+	v9inode = V9FS_I(inode);
+	v9ses = v9fs_inode2v9ses(inode);
+	if (v9fs_proto_dotl(v9ses))
+		omode = v9fs_open_to_dotl_flags(file->f_flags);
+	else
+		omode = v9fs_uflags2omode(file->f_flags,
+					v9fs_proto_dotu(v9ses));
+	fid = file->private_data;
+	if (!fid) {
+		fid = v9fs_fid_clone(file->f_path.dentry);
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		err = p9_client_open(fid, omode);
+		if (err < 0) {
+			p9_client_clunk(fid);
+			return err;
+		}
+		if ((file->f_flags & O_APPEND) &&
+			(!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
+			generic_file_llseek(file, 0, SEEK_END);
+	}
+
+	file->private_data = fid;
+	mutex_lock(&v9inode->v_mutex);
+	if (v9ses->cache && !v9inode->writeback_fid &&
+	    ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
+		/*
+		 * clone a fid and add it to writeback_fid
+		 * we do it during open time instead of
+		 * page dirty time via write_begin/page_mkwrite
+		 * because we want write after unlink usecase
+		 * to work.
+		 */
+		fid = v9fs_writeback_fid(file->f_path.dentry);
+		if (IS_ERR(fid)) {
+			err = PTR_ERR(fid);
+			mutex_unlock(&v9inode->v_mutex);
+			goto out_error;
+		}
+		v9inode->writeback_fid = (void *) fid;
+	}
+	mutex_unlock(&v9inode->v_mutex);
+#ifdef CONFIG_9P_FSCACHE
+	if (v9ses->cache)
+		v9fs_cache_inode_set_cookie(inode, file);
+#endif
+	return 0;
+out_error:
+	p9_client_clunk(file->private_data);
+	file->private_data = NULL;
+	return err;
+}
+
+/**
+ * v9fs_file_lock - lock a file (or directory)
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ * Bugs: this looks like a local only lock, we should extend into 9P
+ *       by using open exclusive
+ */
+
+static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	int res = 0;
+	struct inode *inode = file_inode(filp);
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		return -ENOLCK;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+
+	return res;
+}
+
+static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	struct p9_flock flock;
+	struct p9_fid *fid;
+	uint8_t status;
+	int res = 0;
+	unsigned char fl_type;
+
+	fid = filp->private_data;
+	BUG_ON(fid == NULL);
+
+	if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
+		BUG();
+
+	res = posix_lock_file_wait(filp, fl);
+	if (res < 0)
+		goto out;
+
+	/* convert posix lock to p9 tlock args */
+	memset(&flock, 0, sizeof(flock));
+	/* map the lock type */
+	switch (fl->fl_type) {
+	case F_RDLCK:
+		flock.type = P9_LOCK_TYPE_RDLCK;
+		break;
+	case F_WRLCK:
+		flock.type = P9_LOCK_TYPE_WRLCK;
+		break;
+	case F_UNLCK:
+		flock.type = P9_LOCK_TYPE_UNLCK;
+		break;
+	}
+	flock.start = fl->fl_start;
+	if (fl->fl_end == OFFSET_MAX)
+		flock.length = 0;
+	else
+		flock.length = fl->fl_end - fl->fl_start + 1;
+	flock.proc_id = fl->fl_pid;
+	flock.client_id = utsname()->nodename;
+	if (IS_SETLKW(cmd))
+		flock.flags = P9_LOCK_FLAGS_BLOCK;
+
+	/*
+	 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
+	 * for lock request, keep on trying
+	 */
+	for (;;) {
+		res = p9_client_lock_dotl(fid, &flock, &status);
+		if (res < 0)
+			break;
+
+		if (status != P9_LOCK_BLOCKED)
+			break;
+		if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
+			break;
+		if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
+			break;
+	}
+
+	/* map 9p status to VFS status */
+	switch (status) {
+	case P9_LOCK_SUCCESS:
+		res = 0;
+		break;
+	case P9_LOCK_BLOCKED:
+		res = -EAGAIN;
+		break;
+	case P9_LOCK_ERROR:
+	case P9_LOCK_GRACE:
+		res = -ENOLCK;
+		break;
+	default:
+		BUG();
+	}
+
+	/*
+	 * incase server returned error for lock request, revert
+	 * it locally
+	 */
+	if (res < 0 && fl->fl_type != F_UNLCK) {
+		fl_type = fl->fl_type;
+		fl->fl_type = F_UNLCK;
+		res = posix_lock_file_wait(filp, fl);
+		fl->fl_type = fl_type;
+	}
+out:
+	return res;
+}
+
+static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
+{
+	struct p9_getlock glock;
+	struct p9_fid *fid;
+	int res = 0;
+
+	fid = filp->private_data;
+	BUG_ON(fid == NULL);
+
+	posix_test_lock(filp, fl);
+	/*
+	 * if we have a conflicting lock locally, no need to validate
+	 * with server
+	 */
+	if (fl->fl_type != F_UNLCK)
+		return res;
+
+	/* convert posix lock to p9 tgetlock args */
+	memset(&glock, 0, sizeof(glock));
+	glock.type  = P9_LOCK_TYPE_UNLCK;
+	glock.start = fl->fl_start;
+	if (fl->fl_end == OFFSET_MAX)
+		glock.length = 0;
+	else
+		glock.length = fl->fl_end - fl->fl_start + 1;
+	glock.proc_id = fl->fl_pid;
+	glock.client_id = utsname()->nodename;
+
+	res = p9_client_getlock_dotl(fid, &glock);
+	if (res < 0)
+		return res;
+	/* map 9p lock type to os lock type */
+	switch (glock.type) {
+	case P9_LOCK_TYPE_RDLCK:
+		fl->fl_type = F_RDLCK;
+		break;
+	case P9_LOCK_TYPE_WRLCK:
+		fl->fl_type = F_WRLCK;
+		break;
+	case P9_LOCK_TYPE_UNLCK:
+		fl->fl_type = F_UNLCK;
+		break;
+	}
+	if (glock.type != P9_LOCK_TYPE_UNLCK) {
+		fl->fl_start = glock.start;
+		if (glock.length == 0)
+			fl->fl_end = OFFSET_MAX;
+		else
+			fl->fl_end = glock.start + glock.length - 1;
+		fl->fl_pid = glock.proc_id;
+	}
+	return res;
+}
+
+/**
+ * v9fs_file_lock_dotl - lock a file (or directory)
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ */
+
+static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
+{
+	struct inode *inode = file_inode(filp);
+	int ret = -ENOLCK;
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n",
+		 filp, cmd, fl, filp->f_path.dentry->d_name.name);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		goto out_err;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+
+	if (IS_SETLK(cmd) || IS_SETLKW(cmd))
+		ret = v9fs_file_do_lock(filp, cmd, fl);
+	else if (IS_GETLK(cmd))
+		ret = v9fs_file_getlock(filp, fl);
+	else
+		ret = -EINVAL;
+out_err:
+	return ret;
+}
+
+/**
+ * v9fs_file_flock_dotl - lock a file
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ */
+
+static int v9fs_file_flock_dotl(struct file *filp, int cmd,
+	struct file_lock *fl)
+{
+	struct inode *inode = file_inode(filp);
+	int ret = -ENOLCK;
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %s\n",
+		 filp, cmd, fl, filp->f_path.dentry->d_name.name);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		goto out_err;
+
+	if (!(fl->fl_flags & FL_FLOCK))
+		goto out_err;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+	/* Convert flock to posix lock */
+	fl->fl_owner = (fl_owner_t)filp;
+	fl->fl_start = 0;
+	fl->fl_end = OFFSET_MAX;
+	fl->fl_flags |= FL_POSIX;
+	fl->fl_flags ^= FL_FLOCK;
+
+	if (IS_SETLK(cmd) | IS_SETLKW(cmd))
+		ret = v9fs_file_do_lock(filp, cmd, fl);
+	else
+		ret = -EINVAL;
+out_err:
+	return ret;
+}
+
+/**
+ * v9fs_fid_readn - read from a fid
+ * @fid: fid to read
+ * @data: data buffer to read data into
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+ssize_t
+v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
+	       u64 offset)
+{
+	int n, total, size;
+
+	p9_debug(P9_DEBUG_VFS, "fid %d offset %llu count %d\n",
+		 fid->fid, (long long unsigned)offset, count);
+	n = 0;
+	total = 0;
+	size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
+	do {
+		n = p9_client_read(fid, data, udata, offset, count);
+		if (n <= 0)
+			break;
+
+		if (data)
+			data += n;
+		if (udata)
+			udata += n;
+
+		offset += n;
+		count -= n;
+		total += n;
+	} while (count > 0 && n == size);
+
+	if (n < 0)
+		total = n;
+
+	return total;
+}
+
+/**
+ * v9fs_file_readn - read from a file
+ * @filp: file pointer to read
+ * @data: data buffer to read data into
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+ssize_t
+v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
+	       u64 offset)
+{
+	return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
+}
+
+/**
+ * v9fs_file_read - read from a file
+ * @filp: file pointer to read
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+static ssize_t
+v9fs_file_read(struct file *filp, char __user *udata, size_t count,
+	       loff_t * offset)
+{
+	int ret;
+	struct p9_fid *fid;
+	size_t size;
+
+	p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
+	fid = filp->private_data;
+
+	size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
+	if (count > size)
+		ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
+	else
+		ret = p9_client_read(fid, NULL, udata, *offset, count);
+
+	if (ret > 0)
+		*offset += ret;
+
+	return ret;
+}
+
+ssize_t
+v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
+			 const char __user *data, size_t count,
+			 loff_t *offset, int invalidate)
+{
+	int n;
+	loff_t i_size;
+	size_t total = 0;
+	struct p9_client *clnt;
+	loff_t origin = *offset;
+	unsigned long pg_start, pg_end;
+
+	p9_debug(P9_DEBUG_VFS, "data %p count %d offset %x\n",
+		 data, (int)count, (int)*offset);
+
+	clnt = fid->clnt;
+	do {
+		n = p9_client_write(fid, NULL, data+total, origin+total, count);
+		if (n <= 0)
+			break;
+		count -= n;
+		total += n;
+	} while (count > 0);
+
+	if (invalidate && (total > 0)) {
+		pg_start = origin >> PAGE_CACHE_SHIFT;
+		pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
+		if (inode->i_mapping && inode->i_mapping->nrpages)
+			invalidate_inode_pages2_range(inode->i_mapping,
+						      pg_start, pg_end);
+		*offset += total;
+		i_size = i_size_read(inode);
+		if (*offset > i_size) {
+			inode_add_bytes(inode, *offset - i_size);
+			i_size_write(inode, *offset);
+		}
+	}
+	if (n < 0)
+		return n;
+
+	return total;
+}
+
+/**
+ * v9fs_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+static ssize_t
+v9fs_file_write(struct file *filp, const char __user * data,
+		size_t count, loff_t *offset)
+{
+	ssize_t retval = 0;
+	loff_t origin = *offset;
+
+
+	retval = generic_write_checks(filp, &origin, &count, 0);
+	if (retval)
+		goto out;
+
+	retval = -EINVAL;
+	if ((ssize_t) count < 0)
+		goto out;
+	retval = 0;
+	if (!count)
+		goto out;
+
+	retval = v9fs_file_write_internal(file_inode(filp),
+					filp->private_data,
+					data, count, &origin, 1);
+	/* update offset on successful write */
+	if (retval > 0)
+		*offset = origin;
+out:
+	return retval;
+}
+
+
+static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
+			   int datasync)
+{
+	struct p9_fid *fid;
+	struct inode *inode = filp->f_mapping->host;
+	struct p9_wstat wstat;
+	int retval;
+
+	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (retval)
+		return retval;
+
+	mutex_lock(&inode->i_mutex);
+	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
+
+	fid = filp->private_data;
+	v9fs_blank_wstat(&wstat);
+
+	retval = p9_client_wstat(fid, &wstat);
+	mutex_unlock(&inode->i_mutex);
+
+	return retval;
+}
+
+int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
+			 int datasync)
+{
+	struct p9_fid *fid;
+	struct inode *inode = filp->f_mapping->host;
+	int retval;
+
+	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (retval)
+		return retval;
+
+	mutex_lock(&inode->i_mutex);
+	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
+
+	fid = filp->private_data;
+
+	retval = p9_client_fsync(fid, datasync);
+	mutex_unlock(&inode->i_mutex);
+
+	return retval;
+}
+
+static int
+v9fs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	int retval;
+
+	retval = generic_file_mmap(file, vma);
+	if (!retval)
+		vma->vm_ops = &v9fs_file_vm_ops;
+
+	return retval;
+}
+
+static int
+v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct v9fs_inode *v9inode;
+	struct page *page = vmf->page;
+	struct file *filp = vma->vm_file;
+	struct inode *inode = file_inode(filp);
+
+
+	p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
+		 page, (unsigned long)filp->private_data);
+
+	/* Update file times before taking page lock */
+	file_update_time(filp);
+
+	v9inode = V9FS_I(inode);
+	/* make sure the cache has finished storing the page */
+	v9fs_fscache_wait_on_page_write(inode, page);
+	BUG_ON(!v9inode->writeback_fid);
+	lock_page(page);
+	if (page->mapping != inode->i_mapping)
+		goto out_unlock;
+	wait_for_stable_page(page);
+
+	return VM_FAULT_LOCKED;
+out_unlock:
+	unlock_page(page);
+	return VM_FAULT_NOPAGE;
+}
+
+static ssize_t
+v9fs_direct_read(struct file *filp, char __user *udata, size_t count,
+		 loff_t *offsetp)
+{
+	loff_t size, offset;
+	struct inode *inode;
+	struct address_space *mapping;
+
+	offset = *offsetp;
+	mapping = filp->f_mapping;
+	inode = mapping->host;
+	if (!count)
+		return 0;
+	size = i_size_read(inode);
+	if (offset < size)
+		filemap_write_and_wait_range(mapping, offset,
+					     offset + count - 1);
+
+	return v9fs_file_read(filp, udata, count, offsetp);
+}
+
+/**
+ * v9fs_cached_file_read - read from a file
+ * @filp: file pointer to read
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+static ssize_t
+v9fs_cached_file_read(struct file *filp, char __user *data, size_t count,
+		      loff_t *offset)
+{
+	if (filp->f_flags & O_DIRECT)
+		return v9fs_direct_read(filp, data, count, offset);
+	return do_sync_read(filp, data, count, offset);
+}
+
+static ssize_t
+v9fs_direct_write(struct file *filp, const char __user * data,
+		  size_t count, loff_t *offsetp)
+{
+	loff_t offset;
+	ssize_t retval;
+	struct inode *inode;
+	struct address_space *mapping;
+
+	offset = *offsetp;
+	mapping = filp->f_mapping;
+	inode = mapping->host;
+	if (!count)
+		return 0;
+
+	mutex_lock(&inode->i_mutex);
+	retval = filemap_write_and_wait_range(mapping, offset,
+					      offset + count - 1);
+	if (retval)
+		goto err_out;
+	/*
+	 * After a write we want buffered reads to be sure to go to disk to get
+	 * the new data.  We invalidate clean cached page from the region we're
+	 * about to write.  We do this *before* the write so that if we fail
+	 * here we fall back to buffered write
+	 */
+	if (mapping->nrpages) {
+		pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
+		pgoff_t pg_end   = (offset + count - 1) >> PAGE_CACHE_SHIFT;
+
+		retval = invalidate_inode_pages2_range(mapping,
+							pg_start, pg_end);
+		/*
+		 * If a page can not be invalidated, fall back
+		 * to buffered write.
+		 */
+		if (retval) {
+			if (retval == -EBUSY)
+				goto buff_write;
+			goto err_out;
+		}
+	}
+	retval = v9fs_file_write(filp, data, count, offsetp);
+err_out:
+	mutex_unlock(&inode->i_mutex);
+	return retval;
+
+buff_write:
+	mutex_unlock(&inode->i_mutex);
+	return do_sync_write(filp, data, count, offsetp);
+}
+
+/**
+ * v9fs_cached_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+static ssize_t
+v9fs_cached_file_write(struct file *filp, const char __user * data,
+		       size_t count, loff_t *offset)
+{
+
+	if (filp->f_flags & O_DIRECT)
+		return v9fs_direct_write(filp, data, count, offset);
+	return do_sync_write(filp, data, count, offset);
+}
+
+static const struct vm_operations_struct v9fs_file_vm_ops = {
+	.fault = filemap_fault,
+	.page_mkwrite = v9fs_vm_page_mkwrite,
+	.remap_pages = generic_file_remap_pages,
+};
+
+
+const struct file_operations v9fs_cached_file_operations = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_cached_file_read,
+	.write = v9fs_cached_file_write,
+	.aio_read = generic_file_aio_read,
+	.aio_write = generic_file_aio_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = v9fs_file_mmap,
+	.fsync = v9fs_file_fsync,
+};
+
+const struct file_operations v9fs_cached_file_operations_dotl = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_cached_file_read,
+	.write = v9fs_cached_file_write,
+	.aio_read = generic_file_aio_read,
+	.aio_write = generic_file_aio_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock_dotl,
+	.flock = v9fs_file_flock_dotl,
+	.mmap = v9fs_file_mmap,
+	.fsync = v9fs_file_fsync_dotl,
+};
+
+const struct file_operations v9fs_file_operations = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_file_read,
+	.write = v9fs_file_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = generic_file_readonly_mmap,
+	.fsync = v9fs_file_fsync,
+};
+
+const struct file_operations v9fs_file_operations_dotl = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_file_read,
+	.write = v9fs_file_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock_dotl,
+	.flock = v9fs_file_flock_dotl,
+	.mmap = generic_file_readonly_mmap,
+	.fsync = v9fs_file_fsync_dotl,
+};

addons/9p/src/3.10.108/vfs_super.c

@@ -0,0 +1,368 @@
+/*
+ *  linux/fs/9p/vfs_super.c
+ *
+ * This file contians superblock ops for 9P2000. It is intended that
+ * you mount this file system on directories.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/statfs.h>
+#include <linux/magic.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+#include "xattr.h"
+#include "acl.h"
+
+static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
+
+/**
+ * v9fs_set_super - set the superblock
+ * @s: super block
+ * @data: file system specific data
+ *
+ */
+
+static int v9fs_set_super(struct super_block *s, void *data)
+{
+	s->s_fs_info = data;
+	return set_anon_super(s, data);
+}
+
+/**
+ * v9fs_fill_super - populate superblock with info
+ * @sb: superblock
+ * @v9ses: session information
+ * @flags: flags propagated from v9fs_mount()
+ *
+ */
+
+static void
+v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
+		int flags, void *data)
+{
+	sb->s_maxbytes = MAX_LFS_FILESIZE;
+	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
+	sb->s_blocksize = 1 << sb->s_blocksize_bits;
+	sb->s_magic = V9FS_MAGIC;
+	if (v9fs_proto_dotl(v9ses)) {
+		sb->s_op = &v9fs_super_ops_dotl;
+		sb->s_xattr = v9fs_xattr_handlers;
+	} else
+		sb->s_op = &v9fs_super_ops;
+	sb->s_bdi = &v9ses->bdi;
+	if (v9ses->cache)
+		sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_CACHE_SIZE;
+
+	sb->s_flags |= MS_ACTIVE | MS_DIRSYNC | MS_NOATIME;
+	if (!v9ses->cache)
+		sb->s_flags |= MS_SYNCHRONOUS;
+
+#ifdef CONFIG_9P_FS_POSIX_ACL
+	if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
+		sb->s_flags |= MS_POSIXACL;
+#endif
+
+	save_mount_options(sb, data);
+}
+
+/**
+ * v9fs_mount - mount a superblock
+ * @fs_type: file system type
+ * @flags: mount flags
+ * @dev_name: device name that was mounted
+ * @data: mount options
+ *
+ */
+
+static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
+		       const char *dev_name, void *data)
+{
+	struct super_block *sb = NULL;
+	struct inode *inode = NULL;
+	struct dentry *root = NULL;
+	struct v9fs_session_info *v9ses = NULL;
+	umode_t mode = S_IRWXUGO | S_ISVTX;
+	struct p9_fid *fid;
+	int retval = 0;
+
+	p9_debug(P9_DEBUG_VFS, "\n");
+
+	v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
+	if (!v9ses)
+		return ERR_PTR(-ENOMEM);
+
+	fid = v9fs_session_init(v9ses, dev_name, data);
+	if (IS_ERR(fid)) {
+		retval = PTR_ERR(fid);
+		/*
+		 * we need to call session_close to tear down some
+		 * of the data structure setup by session_init
+		 */
+		goto close_session;
+	}
+
+	sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
+	if (IS_ERR(sb)) {
+		retval = PTR_ERR(sb);
+		goto clunk_fid;
+	}
+	v9fs_fill_super(sb, v9ses, flags, data);
+
+	if (v9ses->cache)
+		sb->s_d_op = &v9fs_cached_dentry_operations;
+	else
+		sb->s_d_op = &v9fs_dentry_operations;
+
+	inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
+	if (IS_ERR(inode)) {
+		retval = PTR_ERR(inode);
+		goto release_sb;
+	}
+
+	root = d_make_root(inode);
+	if (!root) {
+		retval = -ENOMEM;
+		goto release_sb;
+	}
+	sb->s_root = root;
+	if (v9fs_proto_dotl(v9ses)) {
+		struct p9_stat_dotl *st = NULL;
+		st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
+		if (IS_ERR(st)) {
+			retval = PTR_ERR(st);
+			goto release_sb;
+		}
+		root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
+		v9fs_stat2inode_dotl(st, root->d_inode);
+		kfree(st);
+	} else {
+		struct p9_wstat *st = NULL;
+		st = p9_client_stat(fid);
+		if (IS_ERR(st)) {
+			retval = PTR_ERR(st);
+			goto release_sb;
+		}
+
+		root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
+		v9fs_stat2inode(st, root->d_inode, sb);
+
+		p9stat_free(st);
+		kfree(st);
+	}
+	retval = v9fs_get_acl(inode, fid);
+	if (retval)
+		goto release_sb;
+	v9fs_fid_add(root, fid);
+
+	p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
+	return dget(sb->s_root);
+
+clunk_fid:
+	p9_client_clunk(fid);
+close_session:
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+	return ERR_PTR(retval);
+
+release_sb:
+	/*
+	 * we will do the session_close and root dentry release
+	 * in the below call. But we need to clunk fid, because we haven't
+	 * attached the fid to dentry so it won't get clunked
+	 * automatically.
+	 */
+	p9_client_clunk(fid);
+	deactivate_locked_super(sb);
+	return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_kill_super - Kill Superblock
+ * @s: superblock
+ *
+ */
+
+static void v9fs_kill_super(struct super_block *s)
+{
+	struct v9fs_session_info *v9ses = s->s_fs_info;
+
+	p9_debug(P9_DEBUG_VFS, " %p\n", s);
+
+	kill_anon_super(s);
+
+	v9fs_session_cancel(v9ses);
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+	s->s_fs_info = NULL;
+	p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
+}
+
+static void
+v9fs_umount_begin(struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses;
+
+	v9ses = sb->s_fs_info;
+	v9fs_session_begin_cancel(v9ses);
+}
+
+static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_rstatfs rs;
+	int res;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid)) {
+		res = PTR_ERR(fid);
+		goto done;
+	}
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	if (v9fs_proto_dotl(v9ses)) {
+		res = p9_client_statfs(fid, &rs);
+		if (res == 0) {
+			buf->f_type = rs.type;
+			buf->f_bsize = rs.bsize;
+			buf->f_blocks = rs.blocks;
+			buf->f_bfree = rs.bfree;
+			buf->f_bavail = rs.bavail;
+			buf->f_files = rs.files;
+			buf->f_ffree = rs.ffree;
+			buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL;
+			buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
+			buf->f_namelen = rs.namelen;
+		}
+		if (res != -ENOSYS)
+			goto done;
+	}
+	res = simple_statfs(dentry, buf);
+done:
+	return res;
+}
+
+static int v9fs_drop_inode(struct inode *inode)
+{
+	struct v9fs_session_info *v9ses;
+	v9ses = v9fs_inode2v9ses(inode);
+	if (v9ses->cache)
+		return generic_drop_inode(inode);
+	/*
+	 * in case of non cached mode always drop the
+	 * the inode because we want the inode attribute
+	 * to always match that on the server.
+	 */
+	return 1;
+}
+
+static int v9fs_write_inode(struct inode *inode,
+			    struct writeback_control *wbc)
+{
+	int ret;
+	struct p9_wstat wstat;
+	struct v9fs_inode *v9inode;
+	/*
+	 * send an fsync request to server irrespective of
+	 * wbc->sync_mode.
+	 */
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
+	v9inode = V9FS_I(inode);
+	if (!v9inode->writeback_fid)
+		return 0;
+	v9fs_blank_wstat(&wstat);
+
+	ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
+	if (ret < 0) {
+		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+		return ret;
+	}
+	return 0;
+}
+
+static int v9fs_write_inode_dotl(struct inode *inode,
+				 struct writeback_control *wbc)
+{
+	int ret;
+	struct v9fs_inode *v9inode;
+	/*
+	 * send an fsync request to server irrespective of
+	 * wbc->sync_mode.
+	 */
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
+	v9inode = V9FS_I(inode);
+	if (!v9inode->writeback_fid)
+		return 0;
+	ret = p9_client_fsync(v9inode->writeback_fid, 0);
+	if (ret < 0) {
+		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+		return ret;
+	}
+	return 0;
+}
+
+static const struct super_operations v9fs_super_ops = {
+	.alloc_inode = v9fs_alloc_inode,
+	.destroy_inode = v9fs_destroy_inode,
+	.statfs = simple_statfs,
+	.evict_inode = v9fs_evict_inode,
+	.show_options = generic_show_options,
+	.umount_begin = v9fs_umount_begin,
+	.write_inode = v9fs_write_inode,
+};
+
+static const struct super_operations v9fs_super_ops_dotl = {
+	.alloc_inode = v9fs_alloc_inode,
+	.destroy_inode = v9fs_destroy_inode,
+	.statfs = v9fs_statfs,
+	.drop_inode = v9fs_drop_inode,
+	.evict_inode = v9fs_evict_inode,
+	.show_options = generic_show_options,
+	.umount_begin = v9fs_umount_begin,
+	.write_inode = v9fs_write_inode_dotl,
+};
+
+struct file_system_type v9fs_fs_type = {
+	.name = "9p",
+	.mount = v9fs_mount,
+	.kill_sb = v9fs_kill_super,
+	.owner = THIS_MODULE,
+	.fs_flags = FS_RENAME_DOES_D_MOVE,
+};
+MODULE_ALIAS_FS("9p");

addons/9p/src/3.10.108/xattr.c

@@ -0,0 +1,175 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "fid.h"
+#include "xattr.h"
+
+ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
+			   void *buffer, size_t buffer_size)
+{
+	ssize_t retval;
+	int msize, read_count;
+	u64 offset = 0, attr_size;
+	struct p9_fid *attr_fid;
+
+	attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
+	if (IS_ERR(attr_fid)) {
+		retval = PTR_ERR(attr_fid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_attrwalk failed %zd\n",
+			 retval);
+		attr_fid = NULL;
+		goto error;
+	}
+	if (!buffer_size) {
+		/* request to get the attr_size */
+		retval = attr_size;
+		goto error;
+	}
+	if (attr_size > buffer_size) {
+		retval = -ERANGE;
+		goto error;
+	}
+	msize = attr_fid->clnt->msize;
+	while (attr_size) {
+		if (attr_size > (msize - P9_IOHDRSZ))
+			read_count = msize - P9_IOHDRSZ;
+		else
+			read_count = attr_size;
+		read_count = p9_client_read(attr_fid, ((char *)buffer)+offset,
+					NULL, offset, read_count);
+		if (read_count < 0) {
+			/* error in xattr read */
+			retval = read_count;
+			goto error;
+		}
+		offset += read_count;
+		attr_size -= read_count;
+	}
+	/* Total read xattr bytes */
+	retval = offset;
+error:
+	if (attr_fid)
+		p9_client_clunk(attr_fid);
+	return retval;
+
+}
+
+
+/*
+ * v9fs_xattr_get()
+ *
+ * Copy an extended attribute into the buffer
+ * provided, or compute the buffer size required.
+ * Buffer is NULL to compute the size of the buffer required.
+ *
+ * Returns a negative error number on failure, or the number of bytes
+ * used / required on success.
+ */
+ssize_t v9fs_xattr_get(struct dentry *dentry, const char *name,
+		       void *buffer, size_t buffer_size)
+{
+	struct p9_fid *fid;
+
+	p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu\n",
+		 name, buffer_size);
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	return v9fs_fid_xattr_get(fid, name, buffer, buffer_size);
+}
+
+/*
+ * v9fs_xattr_set()
+ *
+ * Create, replace or remove an extended attribute for this inode. Buffer
+ * is NULL to remove an existing extended attribute, and non-NULL to
+ * either replace an existing extended attribute, or create a new extended
+ * attribute. The flags XATTR_REPLACE and XATTR_CREATE
+ * specify that an extended attribute must exist and must not exist
+ * previous to the call, respectively.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+int v9fs_xattr_set(struct dentry *dentry, const char *name,
+		   const void *value, size_t value_len, int flags)
+{
+	struct p9_fid *fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+	return v9fs_fid_xattr_set(fid, name, value, value_len, flags);
+}
+
+int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
+		   const void *value, size_t value_len, int flags)
+{
+	u64 offset = 0;
+	int retval, msize, write_count;
+
+	p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu flags = %d\n",
+		 name, value_len, flags);
+
+	/* Clone it */
+	fid = p9_client_walk(fid, 0, NULL, 1);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	/*
+	 * On success fid points to xattr
+	 */
+	retval = p9_client_xattrcreate(fid, name, value_len, flags);
+	if (retval < 0) {
+		p9_debug(P9_DEBUG_VFS, "p9_client_xattrcreate failed %d\n",
+			 retval);
+		p9_client_clunk(fid);
+		return retval;
+	}
+	msize = fid->clnt->msize;
+	while (value_len) {
+		if (value_len > (msize - P9_IOHDRSZ))
+			write_count = msize - P9_IOHDRSZ;
+		else
+			write_count = value_len;
+		write_count = p9_client_write(fid, ((char *)value)+offset,
+					NULL, offset, write_count);
+		if (write_count < 0) {
+			/* error in xattr write */
+			retval = write_count;
+			break;
+		}
+		offset += write_count;
+		value_len -= write_count;
+	}
+	return p9_client_clunk(fid);
+}
+
+ssize_t v9fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
+{
+	return v9fs_xattr_get(dentry, NULL, buffer, buffer_size);
+}
+
+const struct xattr_handler *v9fs_xattr_handlers[] = {
+	&v9fs_xattr_user_handler,
+#ifdef CONFIG_9P_FS_POSIX_ACL
+	&v9fs_xattr_acl_access_handler,
+	&v9fs_xattr_acl_default_handler,
+#endif
+	NULL
+};

addons/9p/src/3.10.108/xattr.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+#ifndef FS_9P_XATTR_H
+#define FS_9P_XATTR_H
+
+#include <linux/xattr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+extern const struct xattr_handler *v9fs_xattr_handlers[];
+extern struct xattr_handler v9fs_xattr_user_handler;
+extern const struct xattr_handler v9fs_xattr_acl_access_handler;
+extern const struct xattr_handler v9fs_xattr_acl_default_handler;
+
+extern ssize_t v9fs_fid_xattr_get(struct p9_fid *, const char *,
+				  void *, size_t);
+extern ssize_t v9fs_xattr_get(struct dentry *, const char *,
+			      void *, size_t);
+extern int v9fs_fid_xattr_set(struct p9_fid *, const char *,
+			  const void *, size_t, int);
+extern int v9fs_xattr_set(struct dentry *, const char *,
+			  const void *, size_t, int);
+extern ssize_t v9fs_listxattr(struct dentry *, char *, size_t);
+#endif /* FS_9P_XATTR_H */

addons/9p/src/3.10.108/xattr_user.c

@@ -0,0 +1,80 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include "xattr.h"
+
+static int v9fs_xattr_user_get(struct dentry *dentry, const char *name,
+			void *buffer, size_t size, int type)
+{
+	int retval;
+	char *full_name;
+	size_t name_len;
+	size_t prefix_len = XATTR_USER_PREFIX_LEN;
+
+	if (name == NULL)
+		return -EINVAL;
+
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+
+	name_len = strlen(name);
+	full_name = kmalloc(prefix_len + name_len + 1 , GFP_KERNEL);
+	if (!full_name)
+		return -ENOMEM;
+	memcpy(full_name, XATTR_USER_PREFIX, prefix_len);
+	memcpy(full_name+prefix_len, name, name_len);
+	full_name[prefix_len + name_len] = '\0';
+
+	retval = v9fs_xattr_get(dentry, full_name, buffer, size);
+	kfree(full_name);
+	return retval;
+}
+
+static int v9fs_xattr_user_set(struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags, int type)
+{
+	int retval;
+	char *full_name;
+	size_t name_len;
+	size_t prefix_len = XATTR_USER_PREFIX_LEN;
+
+	if (name == NULL)
+		return -EINVAL;
+
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+
+	name_len = strlen(name);
+	full_name = kmalloc(prefix_len + name_len + 1 , GFP_KERNEL);
+	if (!full_name)
+		return -ENOMEM;
+	memcpy(full_name, XATTR_USER_PREFIX, prefix_len);
+	memcpy(full_name + prefix_len, name, name_len);
+	full_name[prefix_len + name_len] = '\0';
+
+	retval = v9fs_xattr_set(dentry, full_name, value, size, flags);
+	kfree(full_name);
+	return retval;
+}
+
+struct xattr_handler v9fs_xattr_user_handler = {
+	.prefix	= XATTR_USER_PREFIX,
+	.get	= v9fs_xattr_user_get,
+	.set	= v9fs_xattr_user_set,
+};

addons/9p/src/4.4.180/Makefile

@@ -0,0 +1,35 @@
+obj-m := 9p.o
+
+9p-objs := \
+	vfs_super.o \
+	vfs_inode.o \
+	vfs_inode_dotl.o \
+	vfs_addr.o \
+	vfs_file.o \
+	vfs_dir.o \
+	vfs_dentry.o \
+	v9fs.o \
+	fid.o  \
+	xattr.o
+
+9p-y += cache.o
+9p-n += acl.o
+
+obj-m := 9pnet.o
+obj-m += 9pnet_virtio.o
+obj-n += 9pnet_rdma.o
+
+9pnet-objs := \
+        mod.o \
+        client.o \
+        error.o \
+        util.o \
+        protocol.o \
+        trans_fd.o \
+        trans_common.o \
+
+9pnet_virtio-objs := \
+        trans_virtio.o
+
+9pnet_rdma-objs := \
+        trans_rdma.o

addons/9p/src/4.4.180/acl.c

@@ -0,0 +1,338 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/posix_acl_xattr.h>
+#include "xattr.h"
+#include "acl.h"
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
+{
+	ssize_t size;
+	void *value = NULL;
+	struct posix_acl *acl = NULL;
+
+	size = v9fs_fid_xattr_get(fid, name, NULL, 0);
+	if (size > 0) {
+		value = kzalloc(size, GFP_NOFS);
+		if (!value)
+			return ERR_PTR(-ENOMEM);
+		size = v9fs_fid_xattr_get(fid, name, value, size);
+		if (size > 0) {
+			acl = posix_acl_from_xattr(&init_user_ns, value, size);
+			if (IS_ERR(acl))
+				goto err_out;
+		}
+	} else if (size == -ENODATA || size == 0 ||
+		   size == -ENOSYS || size == -EOPNOTSUPP) {
+		acl = NULL;
+	} else
+		acl = ERR_PTR(-EIO);
+
+err_out:
+	kfree(value);
+	return acl;
+}
+
+int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
+{
+	int retval = 0;
+	struct posix_acl *pacl, *dacl;
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
+		set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
+		set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
+		return 0;
+	}
+	/* get the default/access acl values and cache them */
+	dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
+	pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
+
+	if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
+		set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
+		set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
+	} else
+		retval = -EIO;
+
+	if (!IS_ERR(dacl))
+		posix_acl_release(dacl);
+
+	if (!IS_ERR(pacl))
+		posix_acl_release(pacl);
+
+	return retval;
+}
+
+static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
+{
+	struct posix_acl *acl;
+	/*
+	 * 9p Always cache the acl value when
+	 * instantiating the inode (v9fs_inode_from_fid)
+	 */
+	acl = get_cached_acl(inode, type);
+	BUG_ON(acl == ACL_NOT_CACHED);
+	return acl;
+}
+
+struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
+{
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
+		/*
+		 * On access = client  and acl = on mode get the acl
+		 * values from the server
+		 */
+		return NULL;
+	}
+	return v9fs_get_cached_acl(inode, type);
+
+}
+
+static int v9fs_set_acl(struct p9_fid *fid, int type, struct posix_acl *acl)
+{
+	int retval;
+	char *name;
+	size_t size;
+	void *buffer;
+	if (!acl)
+		return 0;
+
+	/* Set a setxattr request to server */
+	size = posix_acl_xattr_size(acl->a_count);
+	buffer = kmalloc(size, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+	retval = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
+	if (retval < 0)
+		goto err_free_out;
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = POSIX_ACL_XATTR_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = POSIX_ACL_XATTR_DEFAULT;
+		break;
+	default:
+		BUG();
+	}
+	retval = v9fs_fid_xattr_set(fid, name, buffer, size, 0);
+err_free_out:
+	kfree(buffer);
+	return retval;
+}
+
+int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid)
+{
+	int retval = 0;
+	struct posix_acl *acl;
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
+	if (acl) {
+		retval = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
+		if (retval)
+			return retval;
+		set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
+		retval = v9fs_set_acl(fid, ACL_TYPE_ACCESS, acl);
+		posix_acl_release(acl);
+	}
+	return retval;
+}
+
+int v9fs_set_create_acl(struct inode *inode, struct p9_fid *fid,
+			struct posix_acl *dacl, struct posix_acl *acl)
+{
+	set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
+	set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
+	v9fs_set_acl(fid, ACL_TYPE_DEFAULT, dacl);
+	v9fs_set_acl(fid, ACL_TYPE_ACCESS, acl);
+	return 0;
+}
+
+void v9fs_put_acl(struct posix_acl *dacl,
+		  struct posix_acl *acl)
+{
+	posix_acl_release(dacl);
+	posix_acl_release(acl);
+}
+
+int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+		  struct posix_acl **dpacl, struct posix_acl **pacl)
+{
+	int retval = 0;
+	umode_t mode = *modep;
+	struct posix_acl *acl = NULL;
+
+	if (!S_ISLNK(mode)) {
+		acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		if (!acl)
+			mode &= ~current_umask();
+	}
+	if (acl) {
+		if (S_ISDIR(mode))
+			*dpacl = posix_acl_dup(acl);
+		retval = __posix_acl_create(&acl, GFP_NOFS, &mode);
+		if (retval < 0)
+			return retval;
+		if (retval > 0)
+			*pacl = acl;
+		else
+			posix_acl_release(acl);
+	}
+	*modep  = mode;
+	return 0;
+}
+
+static int v9fs_xattr_get_acl(const struct xattr_handler *handler,
+			      struct dentry *dentry, const char *name,
+			      void *buffer, size_t size)
+{
+	struct v9fs_session_info *v9ses;
+	struct posix_acl *acl;
+	int error;
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	/*
+	 * We allow set/get/list of acl when access=client is not specified
+	 */
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
+		return v9fs_xattr_get(dentry, handler->prefix, buffer, size);
+
+	acl = v9fs_get_cached_acl(d_inode(dentry), handler->flags);
+	if (IS_ERR(acl))
+		return PTR_ERR(acl);
+	if (acl == NULL)
+		return -ENODATA;
+	error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
+	posix_acl_release(acl);
+
+	return error;
+}
+
+static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
+			      struct dentry *dentry, const char *name,
+			      const void *value, size_t size, int flags)
+{
+	int retval;
+	struct posix_acl *acl;
+	struct v9fs_session_info *v9ses;
+	struct inode *inode = d_inode(dentry);
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	/*
+	 * set the attribute on the remote. Without even looking at the
+	 * xattr value. We leave it to the server to validate
+	 */
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
+		return v9fs_xattr_set(dentry, handler->prefix, value, size,
+				      flags);
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+	if (!inode_owner_or_capable(inode))
+		return -EPERM;
+	if (value) {
+		/* update the cached acl value */
+		acl = posix_acl_from_xattr(&init_user_ns, value, size);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		else if (acl) {
+			retval = posix_acl_valid(acl);
+			if (retval)
+				goto err_out;
+		}
+	} else
+		acl = NULL;
+
+	switch (handler->flags) {
+	case ACL_TYPE_ACCESS:
+		if (acl) {
+			struct iattr iattr;
+			struct posix_acl *old_acl = acl;
+
+			retval = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+			if (retval)
+				goto err_out;
+			if (!acl) {
+				/*
+				 * ACL can be represented
+				 * by the mode bits. So don't
+				 * update ACL.
+				 */
+				posix_acl_release(old_acl);
+				value = NULL;
+				size = 0;
+			}
+			iattr.ia_valid = ATTR_MODE;
+			/* FIXME should we update ctime ?
+			 * What is the following setxattr update the
+			 * mode ?
+			 */
+			v9fs_vfs_setattr_dotl(dentry, &iattr);
+		}
+		break;
+	case ACL_TYPE_DEFAULT:
+		if (!S_ISDIR(inode->i_mode)) {
+			retval = acl ? -EINVAL : 0;
+			goto err_out;
+		}
+		break;
+	default:
+		BUG();
+	}
+	retval = v9fs_xattr_set(dentry, handler->prefix, value, size, flags);
+	if (!retval)
+		set_cached_acl(inode, handler->flags, acl);
+err_out:
+	posix_acl_release(acl);
+	return retval;
+}
+
+const struct xattr_handler v9fs_xattr_acl_access_handler = {
+	.prefix	= POSIX_ACL_XATTR_ACCESS,
+	.flags	= ACL_TYPE_ACCESS,
+	.get	= v9fs_xattr_get_acl,
+	.set	= v9fs_xattr_set_acl,
+};
+
+const struct xattr_handler v9fs_xattr_acl_default_handler = {
+	.prefix	= POSIX_ACL_XATTR_DEFAULT,
+	.flags	= ACL_TYPE_DEFAULT,
+	.get	= v9fs_xattr_get_acl,
+	.set	= v9fs_xattr_set_acl,
+};

addons/9p/src/4.4.180/acl.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+#ifndef FS_9P_ACL_H
+#define FS_9P_ACL_H
+
+#ifdef CONFIG_9P_FS_POSIX_ACL
+extern int v9fs_get_acl(struct inode *, struct p9_fid *);
+extern struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type);
+extern int v9fs_acl_chmod(struct inode *, struct p9_fid *);
+extern int v9fs_set_create_acl(struct inode *, struct p9_fid *,
+			       struct posix_acl *, struct posix_acl *);
+extern int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+			 struct posix_acl **dpacl, struct posix_acl **pacl);
+extern void v9fs_put_acl(struct posix_acl *dacl, struct posix_acl *acl);
+#else
+#define v9fs_iop_get_acl NULL
+static inline int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
+{
+	return 0;
+}
+static inline int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid)
+{
+	return 0;
+}
+static inline int v9fs_set_create_acl(struct inode *inode,
+				      struct p9_fid *fid,
+				      struct posix_acl *dacl,
+				      struct posix_acl *acl)
+{
+	return 0;
+}
+static inline void v9fs_put_acl(struct posix_acl *dacl,
+				struct posix_acl *acl)
+{
+}
+static inline int v9fs_acl_mode(struct inode *dir, umode_t *modep,
+				struct posix_acl **dpacl,
+				struct posix_acl **pacl)
+{
+	return 0;
+}
+
+#endif
+#endif /* FS_9P_XATTR_H */

addons/9p/src/4.4.180/cache.c

@@ -0,0 +1,414 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/jiffies.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <net/9p/9p.h>
+
+#include "v9fs.h"
+#include "cache.h"
+
+#define CACHETAG_LEN  11
+
+struct fscache_netfs v9fs_cache_netfs = {
+	.name 		= "9p",
+	.version 	= 0,
+};
+
+/**
+ * v9fs_random_cachetag - Generate a random tag to be associated
+ *			  with a new cache session.
+ *
+ * The value of jiffies is used for a fairly randomly cache tag.
+ */
+
+static
+int v9fs_random_cachetag(struct v9fs_session_info *v9ses)
+{
+	v9ses->cachetag = kmalloc(CACHETAG_LEN, GFP_KERNEL);
+	if (!v9ses->cachetag)
+		return -ENOMEM;
+
+	return scnprintf(v9ses->cachetag, CACHETAG_LEN, "%lu", jiffies);
+}
+
+static uint16_t v9fs_cache_session_get_key(const void *cookie_netfs_data,
+					   void *buffer, uint16_t bufmax)
+{
+	struct v9fs_session_info *v9ses;
+	uint16_t klen = 0;
+
+	v9ses = (struct v9fs_session_info *)cookie_netfs_data;
+	p9_debug(P9_DEBUG_FSC, "session %p buf %p size %u\n",
+		 v9ses, buffer, bufmax);
+
+	if (v9ses->cachetag)
+		klen = strlen(v9ses->cachetag);
+
+	if (klen > bufmax)
+		return 0;
+
+	memcpy(buffer, v9ses->cachetag, klen);
+	p9_debug(P9_DEBUG_FSC, "cache session tag %s\n", v9ses->cachetag);
+	return klen;
+}
+
+const struct fscache_cookie_def v9fs_cache_session_index_def = {
+	.name		= "9P.session",
+	.type		= FSCACHE_COOKIE_TYPE_INDEX,
+	.get_key	= v9fs_cache_session_get_key,
+};
+
+void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
+{
+	/* If no cache session tag was specified, we generate a random one. */
+	if (!v9ses->cachetag)
+		v9fs_random_cachetag(v9ses);
+
+	v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
+						&v9fs_cache_session_index_def,
+						v9ses, true);
+	p9_debug(P9_DEBUG_FSC, "session %p get cookie %p\n",
+		 v9ses, v9ses->fscache);
+}
+
+void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses)
+{
+	p9_debug(P9_DEBUG_FSC, "session %p put cookie %p\n",
+		 v9ses, v9ses->fscache);
+	fscache_relinquish_cookie(v9ses->fscache, 0);
+	v9ses->fscache = NULL;
+}
+
+
+static uint16_t v9fs_cache_inode_get_key(const void *cookie_netfs_data,
+					 void *buffer, uint16_t bufmax)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	memcpy(buffer, &v9inode->qid.path, sizeof(v9inode->qid.path));
+	p9_debug(P9_DEBUG_FSC, "inode %p get key %llu\n",
+		 &v9inode->vfs_inode, v9inode->qid.path);
+	return sizeof(v9inode->qid.path);
+}
+
+static void v9fs_cache_inode_get_attr(const void *cookie_netfs_data,
+				      uint64_t *size)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	*size = i_size_read(&v9inode->vfs_inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p get attr %llu\n",
+		 &v9inode->vfs_inode, *size);
+}
+
+static uint16_t v9fs_cache_inode_get_aux(const void *cookie_netfs_data,
+					 void *buffer, uint16_t buflen)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+	memcpy(buffer, &v9inode->qid.version, sizeof(v9inode->qid.version));
+	p9_debug(P9_DEBUG_FSC, "inode %p get aux %u\n",
+		 &v9inode->vfs_inode, v9inode->qid.version);
+	return sizeof(v9inode->qid.version);
+}
+
+static enum
+fscache_checkaux v9fs_cache_inode_check_aux(void *cookie_netfs_data,
+					    const void *buffer,
+					    uint16_t buflen)
+{
+	const struct v9fs_inode *v9inode = cookie_netfs_data;
+
+	if (buflen != sizeof(v9inode->qid.version))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	if (memcmp(buffer, &v9inode->qid.version,
+		   sizeof(v9inode->qid.version)))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	return FSCACHE_CHECKAUX_OKAY;
+}
+
+static void v9fs_cache_inode_now_uncached(void *cookie_netfs_data)
+{
+	struct v9fs_inode *v9inode = cookie_netfs_data;
+	struct pagevec pvec;
+	pgoff_t first;
+	int loop, nr_pages;
+
+	pagevec_init(&pvec, 0);
+	first = 0;
+
+	for (;;) {
+		nr_pages = pagevec_lookup(&pvec, v9inode->vfs_inode.i_mapping,
+					  first,
+					  PAGEVEC_SIZE - pagevec_count(&pvec));
+		if (!nr_pages)
+			break;
+
+		for (loop = 0; loop < nr_pages; loop++)
+			ClearPageFsCache(pvec.pages[loop]);
+
+		first = pvec.pages[nr_pages - 1]->index + 1;
+
+		pvec.nr = nr_pages;
+		pagevec_release(&pvec);
+		cond_resched();
+	}
+}
+
+const struct fscache_cookie_def v9fs_cache_inode_index_def = {
+	.name		= "9p.inode",
+	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
+	.get_key	= v9fs_cache_inode_get_key,
+	.get_attr	= v9fs_cache_inode_get_attr,
+	.get_aux	= v9fs_cache_inode_get_aux,
+	.check_aux	= v9fs_cache_inode_check_aux,
+	.now_uncached	= v9fs_cache_inode_now_uncached,
+};
+
+void v9fs_cache_inode_get_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode;
+	struct v9fs_session_info *v9ses;
+
+	if (!S_ISREG(inode->i_mode))
+		return;
+
+	v9inode = V9FS_I(inode);
+	if (v9inode->fscache)
+		return;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  v9inode, true);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
+		 inode, v9inode->fscache);
+}
+
+void v9fs_cache_inode_put_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if (!v9inode->fscache)
+		return;
+	p9_debug(P9_DEBUG_FSC, "inode %p put cookie %p\n",
+		 inode, v9inode->fscache);
+
+	fscache_relinquish_cookie(v9inode->fscache, 0);
+	v9inode->fscache = NULL;
+}
+
+void v9fs_cache_inode_flush_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if (!v9inode->fscache)
+		return;
+	p9_debug(P9_DEBUG_FSC, "inode %p flush cookie %p\n",
+		 inode, v9inode->fscache);
+
+	fscache_relinquish_cookie(v9inode->fscache, 1);
+	v9inode->fscache = NULL;
+}
+
+void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if (!v9inode->fscache)
+		return;
+
+	mutex_lock(&v9inode->fscache_lock);
+
+	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
+		v9fs_cache_inode_flush_cookie(inode);
+	else
+		v9fs_cache_inode_get_cookie(inode);
+
+	mutex_unlock(&v9inode->fscache_lock);
+}
+
+void v9fs_cache_inode_reset_cookie(struct inode *inode)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	struct v9fs_session_info *v9ses;
+	struct fscache_cookie *old;
+
+	if (!v9inode->fscache)
+		return;
+
+	old = v9inode->fscache;
+
+	mutex_lock(&v9inode->fscache_lock);
+	fscache_relinquish_cookie(v9inode->fscache, 1);
+
+	v9ses = v9fs_inode2v9ses(inode);
+	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  v9inode, true);
+	p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
+		 inode, old, v9inode->fscache);
+
+	mutex_unlock(&v9inode->fscache_lock);
+}
+
+int __v9fs_fscache_release_page(struct page *page, gfp_t gfp)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	BUG_ON(!v9inode->fscache);
+
+	return fscache_maybe_release_page(v9inode->fscache, page, gfp);
+}
+
+void __v9fs_fscache_invalidate_page(struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	BUG_ON(!v9inode->fscache);
+
+	if (PageFsCache(page)) {
+		fscache_wait_on_page_write(v9inode->fscache, page);
+		BUG_ON(!PageLocked(page));
+		fscache_uncache_page(v9inode->fscache, page);
+	}
+}
+
+static void v9fs_vfs_readpage_complete(struct page *page, void *data,
+				       int error)
+{
+	if (!error)
+		SetPageUptodate(page);
+
+	unlock_page(page);
+}
+
+/**
+ * __v9fs_readpage_from_fscache - read a page from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpage_from_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	if (!v9inode->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_page(v9inode->fscache,
+					 page,
+					 v9fs_vfs_readpage_complete,
+					 NULL,
+					 GFP_KERNEL);
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		p9_debug(P9_DEBUG_FSC, "page/inode not in cache %d\n", ret);
+		return 1;
+	case 0:
+		p9_debug(P9_DEBUG_FSC, "BIO submitted\n");
+		return ret;
+	default:
+		p9_debug(P9_DEBUG_FSC, "ret %d\n", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpages_from_fscache - read multiple pages from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpages_from_fscache(struct inode *inode,
+				  struct address_space *mapping,
+				  struct list_head *pages,
+				  unsigned *nr_pages)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p pages %u\n", inode, *nr_pages);
+	if (!v9inode->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_pages(v9inode->fscache,
+					  mapping, pages, nr_pages,
+					  v9fs_vfs_readpage_complete,
+					  NULL,
+					  mapping_gfp_mask(mapping));
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		p9_debug(P9_DEBUG_FSC, "pages/inodes not in cache %d\n", ret);
+		return 1;
+	case 0:
+		BUG_ON(!list_empty(pages));
+		BUG_ON(*nr_pages != 0);
+		p9_debug(P9_DEBUG_FSC, "BIO submitted\n");
+		return ret;
+	default:
+		p9_debug(P9_DEBUG_FSC, "ret %d\n", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpage_to_fscache - write a page to the cache
+ *
+ */
+
+void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	ret = fscache_write_page(v9inode->fscache, page, GFP_KERNEL);
+	p9_debug(P9_DEBUG_FSC, "ret =  %d\n", ret);
+	if (ret != 0)
+		v9fs_uncache_page(inode, page);
+}
+
+/*
+ * wait for a page to complete writing to the cache
+ */
+void __v9fs_fscache_wait_on_page_write(struct inode *inode, struct page *page)
+{
+	const struct v9fs_inode *v9inode = V9FS_I(inode);
+	p9_debug(P9_DEBUG_FSC, "inode %p page %p\n", inode, page);
+	if (PageFsCache(page))
+		fscache_wait_on_page_write(v9inode->fscache, page);
+}

addons/9p/src/4.4.180/cache.h

@@ -0,0 +1,152 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#ifndef _9P_CACHE_H
+#define _9P_CACHE_H
+#ifdef CONFIG_9P_FSCACHE
+#include <linux/fscache.h>
+#include <linux/spinlock.h>
+
+extern struct fscache_netfs v9fs_cache_netfs;
+extern const struct fscache_cookie_def v9fs_cache_session_index_def;
+extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
+
+extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
+extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
+
+extern void v9fs_cache_inode_get_cookie(struct inode *inode);
+extern void v9fs_cache_inode_put_cookie(struct inode *inode);
+extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
+extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
+extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
+
+extern int __v9fs_cache_register(void);
+extern void __v9fs_cache_unregister(void);
+
+extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
+extern void __v9fs_fscache_invalidate_page(struct page *page);
+extern int __v9fs_readpage_from_fscache(struct inode *inode,
+					struct page *page);
+extern int __v9fs_readpages_from_fscache(struct inode *inode,
+					 struct address_space *mapping,
+					 struct list_head *pages,
+					 unsigned *nr_pages);
+extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
+extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
+					      struct page *page);
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp)
+{
+	return __v9fs_fscache_release_page(page, gfp);
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page)
+{
+	__v9fs_fscache_invalidate_page(page);
+}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return __v9fs_readpage_from_fscache(inode, page);
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return __v9fs_readpages_from_fscache(inode, mapping, pages,
+					     nr_pages);
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{
+	if (PageFsCache(page))
+		__v9fs_readpage_to_fscache(inode, page);
+}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	fscache_uncache_page(v9inode->fscache, page);
+	BUG_ON(PageFsCache(page));
+}
+
+static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page)
+{
+	return __v9fs_fscache_wait_on_page_write(inode, page);
+}
+
+#else /* CONFIG_9P_FSCACHE */
+
+static inline void v9fs_cache_inode_get_cookie(struct inode *inode)
+{
+}
+
+static inline void v9fs_cache_inode_put_cookie(struct inode *inode)
+{
+}
+
+static inline void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *file)
+{
+}
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp) {
+	return 1;
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page) {}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return -ENOBUFS;
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return -ENOBUFS;
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{}
+
+static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
+						   struct page *page)
+{
+	return;
+}
+
+#endif /* CONFIG_9P_FSCACHE */
+#endif /* _9P_CACHE_H */

addons/9p/src/4.4.180/error.c

@@ -0,0 +1,247 @@
+/*
+ * linux/fs/9p/error.c
+ *
+ * Error string handling
+ *
+ * Plan 9 uses error strings, Unix uses error numbers.  These functions
+ * try to help manage that and provide for dynamically adding error
+ * mappings.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/jhash.h>
+#include <linux/errno.h>
+#include <net/9p/9p.h>
+
+/**
+ * struct errormap - map string errors from Plan 9 to Linux numeric ids
+ * @name: string sent over 9P
+ * @val: numeric id most closely representing @name
+ * @namelen: length of string
+ * @list: hash-table list for string lookup
+ */
+struct errormap {
+	char *name;
+	int val;
+
+	int namelen;
+	struct hlist_node list;
+};
+
+#define ERRHASHSZ		32
+static struct hlist_head hash_errmap[ERRHASHSZ];
+
+/* FixMe - reduce to a reasonable size */
+static struct errormap errmap[] = {
+	{"Operation not permitted", EPERM},
+	{"wstat prohibited", EPERM},
+	{"No such file or directory", ENOENT},
+	{"directory entry not found", ENOENT},
+	{"file not found", ENOENT},
+	{"Interrupted system call", EINTR},
+	{"Input/output error", EIO},
+	{"No such device or address", ENXIO},
+	{"Argument list too long", E2BIG},
+	{"Bad file descriptor", EBADF},
+	{"Resource temporarily unavailable", EAGAIN},
+	{"Cannot allocate memory", ENOMEM},
+	{"Permission denied", EACCES},
+	{"Bad address", EFAULT},
+	{"Block device required", ENOTBLK},
+	{"Device or resource busy", EBUSY},
+	{"File exists", EEXIST},
+	{"Invalid cross-device link", EXDEV},
+	{"No such device", ENODEV},
+	{"Not a directory", ENOTDIR},
+	{"Is a directory", EISDIR},
+	{"Invalid argument", EINVAL},
+	{"Too many open files in system", ENFILE},
+	{"Too many open files", EMFILE},
+	{"Text file busy", ETXTBSY},
+	{"File too large", EFBIG},
+	{"No space left on device", ENOSPC},
+	{"Illegal seek", ESPIPE},
+	{"Read-only file system", EROFS},
+	{"Too many links", EMLINK},
+	{"Broken pipe", EPIPE},
+	{"Numerical argument out of domain", EDOM},
+	{"Numerical result out of range", ERANGE},
+	{"Resource deadlock avoided", EDEADLK},
+	{"File name too long", ENAMETOOLONG},
+	{"No locks available", ENOLCK},
+	{"Function not implemented", ENOSYS},
+	{"Directory not empty", ENOTEMPTY},
+	{"Too many levels of symbolic links", ELOOP},
+	{"No message of desired type", ENOMSG},
+	{"Identifier removed", EIDRM},
+	{"No data available", ENODATA},
+	{"Machine is not on the network", ENONET},
+	{"Package not installed", ENOPKG},
+	{"Object is remote", EREMOTE},
+	{"Link has been severed", ENOLINK},
+	{"Communication error on send", ECOMM},
+	{"Protocol error", EPROTO},
+	{"Bad message", EBADMSG},
+	{"File descriptor in bad state", EBADFD},
+	{"Streams pipe error", ESTRPIPE},
+	{"Too many users", EUSERS},
+	{"Socket operation on non-socket", ENOTSOCK},
+	{"Message too long", EMSGSIZE},
+	{"Protocol not available", ENOPROTOOPT},
+	{"Protocol not supported", EPROTONOSUPPORT},
+	{"Socket type not supported", ESOCKTNOSUPPORT},
+	{"Operation not supported", EOPNOTSUPP},
+	{"Protocol family not supported", EPFNOSUPPORT},
+	{"Network is down", ENETDOWN},
+	{"Network is unreachable", ENETUNREACH},
+	{"Network dropped connection on reset", ENETRESET},
+	{"Software caused connection abort", ECONNABORTED},
+	{"Connection reset by peer", ECONNRESET},
+	{"No buffer space available", ENOBUFS},
+	{"Transport endpoint is already connected", EISCONN},
+	{"Transport endpoint is not connected", ENOTCONN},
+	{"Cannot send after transport endpoint shutdown", ESHUTDOWN},
+	{"Connection timed out", ETIMEDOUT},
+	{"Connection refused", ECONNREFUSED},
+	{"Host is down", EHOSTDOWN},
+	{"No route to host", EHOSTUNREACH},
+	{"Operation already in progress", EALREADY},
+	{"Operation now in progress", EINPROGRESS},
+	{"Is a named type file", EISNAM},
+	{"Remote I/O error", EREMOTEIO},
+	{"Disk quota exceeded", EDQUOT},
+/* errors from fossil, vacfs, and u9fs */
+	{"fid unknown or out of range", EBADF},
+	{"permission denied", EACCES},
+	{"file does not exist", ENOENT},
+	{"authentication failed", ECONNREFUSED},
+	{"bad offset in directory read", ESPIPE},
+	{"bad use of fid", EBADF},
+	{"wstat can't convert between files and directories", EPERM},
+	{"directory is not empty", ENOTEMPTY},
+	{"file exists", EEXIST},
+	{"file already exists", EEXIST},
+	{"file or directory already exists", EEXIST},
+	{"fid already in use", EBADF},
+	{"file in use", ETXTBSY},
+	{"i/o error", EIO},
+	{"file already open for I/O", ETXTBSY},
+	{"illegal mode", EINVAL},
+	{"illegal name", ENAMETOOLONG},
+	{"not a directory", ENOTDIR},
+	{"not a member of proposed group", EPERM},
+	{"not owner", EACCES},
+	{"only owner can change group in wstat", EACCES},
+	{"read only file system", EROFS},
+	{"no access to special file", EPERM},
+	{"i/o count too large", EIO},
+	{"unknown group", EINVAL},
+	{"unknown user", EINVAL},
+	{"bogus wstat buffer", EPROTO},
+	{"exclusive use file already open", EAGAIN},
+	{"corrupted directory entry", EIO},
+	{"corrupted file entry", EIO},
+	{"corrupted block label", EIO},
+	{"corrupted meta data", EIO},
+	{"illegal offset", EINVAL},
+	{"illegal path element", ENOENT},
+	{"root of file system is corrupted", EIO},
+	{"corrupted super block", EIO},
+	{"protocol botch", EPROTO},
+	{"file system is full", ENOSPC},
+	{"file is in use", EAGAIN},
+	{"directory entry is not allocated", ENOENT},
+	{"file is read only", EROFS},
+	{"file has been removed", EIDRM},
+	{"only support truncation to zero length", EPERM},
+	{"cannot remove root", EPERM},
+	{"file too big", EFBIG},
+	{"venti i/o error", EIO},
+	/* these are not errors */
+	{"u9fs rhostsauth: no authentication required", 0},
+	{"u9fs authnone: no authentication required", 0},
+	{NULL, -1}
+};
+
+/**
+ * p9_error_init - preload mappings into hash list
+ *
+ */
+
+int p9_error_init(void)
+{
+	struct errormap *c;
+	int bucket;
+
+	/* initialize hash table */
+	for (bucket = 0; bucket < ERRHASHSZ; bucket++)
+		INIT_HLIST_HEAD(&hash_errmap[bucket]);
+
+	/* load initial error map into hash table */
+	for (c = errmap; c->name != NULL; c++) {
+		c->namelen = strlen(c->name);
+		bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
+		INIT_HLIST_NODE(&c->list);
+		hlist_add_head(&c->list, &hash_errmap[bucket]);
+	}
+
+	return 1;
+}
+EXPORT_SYMBOL(p9_error_init);
+
+/**
+ * errstr2errno - convert error string to error number
+ * @errstr: error string
+ * @len: length of error string
+ *
+ */
+
+int p9_errstr2errno(char *errstr, int len)
+{
+	int errno;
+	struct errormap *c;
+	int bucket;
+
+	errno = 0;
+	c = NULL;
+	bucket = jhash(errstr, len, 0) % ERRHASHSZ;
+	hlist_for_each_entry(c, &hash_errmap[bucket], list) {
+		if (c->namelen == len && !memcmp(c->name, errstr, len)) {
+			errno = c->val;
+			break;
+		}
+	}
+
+	if (errno == 0) {
+		/* TODO: if error isn't found, add it dynamically */
+		errstr[len] = 0;
+		pr_err("%s: server reported unknown error %s\n",
+		       __func__, errstr);
+		errno = ESERVERFAULT;
+	}
+
+	return -errno;
+}
+EXPORT_SYMBOL(p9_errstr2errno);

addons/9p/src/4.4.180/fid.c

@@ -0,0 +1,306 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_add - add a fid to a dentry
+ * @dentry: dentry that the fid is being added to
+ * @fid: fid to add
+ *
+ */
+
+static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid)
+{
+	hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata);
+}
+
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
+{
+	spin_lock(&dentry->d_lock);
+	__add_fid(dentry, fid);
+	spin_unlock(&dentry->d_lock);
+}
+
+/**
+ * v9fs_fid_find - retrieve a fid that belongs to the specified uid
+ * @dentry: dentry to look for fid in
+ * @uid: return fid that belongs to the specified user
+ * @any: if non-zero, return any fid associated with the dentry
+ *
+ */
+
+static struct p9_fid *v9fs_fid_find(struct dentry *dentry, kuid_t uid, int any)
+{
+	struct p9_fid *fid, *ret;
+
+	p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p) uid %d any %d\n",
+		 dentry, dentry, from_kuid(&init_user_ns, uid),
+		 any);
+	ret = NULL;
+	/* we'll recheck under lock if there's anything to look in */
+	if (dentry->d_fsdata) {
+		struct hlist_head *h = (struct hlist_head *)&dentry->d_fsdata;
+		spin_lock(&dentry->d_lock);
+		hlist_for_each_entry(fid, h, dlist) {
+			if (any || uid_eq(fid->uid, uid)) {
+				ret = fid;
+				break;
+			}
+		}
+		spin_unlock(&dentry->d_lock);
+	}
+
+	return ret;
+}
+
+/*
+ * We need to hold v9ses->rename_sem as long as we hold references
+ * to returned path array. Array element contain pointers to
+ * dentry names.
+ */
+static int build_path_from_dentry(struct v9fs_session_info *v9ses,
+				  struct dentry *dentry, char ***names)
+{
+	int n = 0, i;
+	char **wnames;
+	struct dentry *ds;
+
+	for (ds = dentry; !IS_ROOT(ds); ds = ds->d_parent)
+		n++;
+
+	wnames = kmalloc(sizeof(char *) * n, GFP_KERNEL);
+	if (!wnames)
+		goto err_out;
+
+	for (ds = dentry, i = (n-1); i >= 0; i--, ds = ds->d_parent)
+		wnames[i] = (char  *)ds->d_name.name;
+
+	*names = wnames;
+	return n;
+err_out:
+	return -ENOMEM;
+}
+
+static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
+					       kuid_t uid, int any)
+{
+	struct dentry *ds;
+	char **wnames, *uname;
+	int i, n, l, clone, access;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid, *old_fid = NULL;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	access = v9ses->flags & V9FS_ACCESS_MASK;
+	fid = v9fs_fid_find(dentry, uid, any);
+	if (fid)
+		return fid;
+	/*
+	 * we don't have a matching fid. To do a TWALK we need
+	 * parent fid. We need to prevent rename when we want to
+	 * look at the parent.
+	 */
+	down_read(&v9ses->rename_sem);
+	ds = dentry->d_parent;
+	fid = v9fs_fid_find(ds, uid, any);
+	if (fid) {
+		/* Found the parent fid do a lookup with that */
+		fid = p9_client_walk(fid, 1, (char **)&dentry->d_name.name, 1);
+		goto fid_out;
+	}
+	up_read(&v9ses->rename_sem);
+
+	/* start from the root and try to do a lookup */
+	fid = v9fs_fid_find(dentry->d_sb->s_root, uid, any);
+	if (!fid) {
+		/* the user is not attached to the fs yet */
+		if (access == V9FS_ACCESS_SINGLE)
+			return ERR_PTR(-EPERM);
+
+		if (v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses))
+				uname = NULL;
+		else
+			uname = v9ses->uname;
+
+		fid = p9_client_attach(v9ses->clnt, NULL, uname, uid,
+				       v9ses->aname);
+		if (IS_ERR(fid))
+			return fid;
+
+		v9fs_fid_add(dentry->d_sb->s_root, fid);
+	}
+	/* If we are root ourself just return that */
+	if (dentry->d_sb->s_root == dentry)
+		return fid;
+	/*
+	 * Do a multipath walk with attached root.
+	 * When walking parent we need to make sure we
+	 * don't have a parallel rename happening
+	 */
+	down_read(&v9ses->rename_sem);
+	n  = build_path_from_dentry(v9ses, dentry, &wnames);
+	if (n < 0) {
+		fid = ERR_PTR(n);
+		goto err_out;
+	}
+	clone = 1;
+	i = 0;
+	while (i < n) {
+		l = min(n - i, P9_MAXWELEM);
+		/*
+		 * We need to hold rename lock when doing a multipath
+		 * walk to ensure none of the patch component change
+		 */
+		fid = p9_client_walk(fid, l, &wnames[i], clone);
+		if (IS_ERR(fid)) {
+			if (old_fid) {
+				/*
+				 * If we fail, clunk fid which are mapping
+				 * to path component and not the last component
+				 * of the path.
+				 */
+				p9_client_clunk(old_fid);
+			}
+			kfree(wnames);
+			goto err_out;
+		}
+		old_fid = fid;
+		i += l;
+		clone = 0;
+	}
+	kfree(wnames);
+fid_out:
+	if (!IS_ERR(fid)) {
+		spin_lock(&dentry->d_lock);
+		if (d_unhashed(dentry)) {
+			spin_unlock(&dentry->d_lock);
+			p9_client_clunk(fid);
+			fid = ERR_PTR(-ENOENT);
+		} else {
+			__add_fid(dentry, fid);
+			spin_unlock(&dentry->d_lock);
+		}
+	}
+err_out:
+	up_read(&v9ses->rename_sem);
+	return fid;
+}
+
+/**
+ * v9fs_fid_lookup - lookup for a fid, try to walk if not found
+ * @dentry: dentry to look for fid in
+ *
+ * Look for a fid in the specified dentry for the current user.
+ * If no fid is found, try to create one walking from a fid from the parent
+ * dentry (if it has one), or the root dentry. If the user haven't accessed
+ * the fs yet, attach now and walk from the root.
+ */
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
+{
+	kuid_t uid;
+	int  any, access;
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	access = v9ses->flags & V9FS_ACCESS_MASK;
+	switch (access) {
+	case V9FS_ACCESS_SINGLE:
+	case V9FS_ACCESS_USER:
+	case V9FS_ACCESS_CLIENT:
+		uid = current_fsuid();
+		any = 0;
+		break;
+
+	case V9FS_ACCESS_ANY:
+		uid = v9ses->uid;
+		any = 1;
+		break;
+
+	default:
+		uid = INVALID_UID;
+		any = 0;
+		break;
+	}
+	return v9fs_fid_lookup_with_uid(dentry, uid, any);
+}
+
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
+{
+	struct p9_fid *fid, *ret;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return fid;
+
+	ret = p9_client_walk(fid, 0, NULL, 1);
+	return ret;
+}
+
+static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, kuid_t uid)
+{
+	struct p9_fid *fid, *ret;
+
+	fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
+	if (IS_ERR(fid))
+		return fid;
+
+	ret = p9_client_walk(fid, 0, NULL, 1);
+	return ret;
+}
+
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
+{
+	int err;
+	struct p9_fid *fid;
+
+	fid = v9fs_fid_clone_with_uid(dentry, GLOBAL_ROOT_UID);
+	if (IS_ERR(fid))
+		goto error_out;
+	/*
+	 * writeback fid will only be used to write back the
+	 * dirty pages. We always request for the open fid in read-write
+	 * mode so that a partial page write which result in page
+	 * read can work.
+	 */
+	err = p9_client_open(fid, O_RDWR);
+	if (err < 0) {
+		p9_client_clunk(fid);
+		fid = ERR_PTR(err);
+		goto error_out;
+	}
+error_out:
+	return fid;
+}

addons/9p/src/4.4.180/fid.h

@@ -0,0 +1,30 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_FID_H
+#define FS_9P_FID_H
+#include <linux/list.h>
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
+struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
+#endif

addons/9p/src/4.4.180/mod.c

@@ -0,0 +1,201 @@
+/*
+ *  net/9p/9p.c
+ *
+ *  9P entry point
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/moduleparam.h>
+#include <net/9p/9p.h>
+#include <linux/fs.h>
+#include <linux/parser.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_NET_9P_DEBUG
+unsigned int p9_debug_level = 0;	/* feature-rific global debug level  */
+EXPORT_SYMBOL(p9_debug_level);
+module_param_named(debug, p9_debug_level, uint, 0);
+MODULE_PARM_DESC(debug, "9P debugging level");
+
+void _p9_debug(enum p9_debug_flags level, const char *func,
+		const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	if ((p9_debug_level & level) != level)
+		return;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	if (level == P9_DEBUG_9P)
+		pr_notice("(%8.8d) %pV", task_pid_nr(current), &vaf);
+	else
+		pr_notice("-- %s (%d): %pV", func, task_pid_nr(current), &vaf);
+
+	va_end(args);
+}
+EXPORT_SYMBOL(_p9_debug);
+#endif
+
+/*
+ * Dynamic Transport Registration Routines
+ *
+ */
+
+static DEFINE_SPINLOCK(v9fs_trans_lock);
+static LIST_HEAD(v9fs_trans_list);
+
+/**
+ * v9fs_register_trans - register a new transport with 9p
+ * @m: structure describing the transport module and entry points
+ *
+ */
+void v9fs_register_trans(struct p9_trans_module *m)
+{
+	spin_lock(&v9fs_trans_lock);
+	list_add_tail(&m->list, &v9fs_trans_list);
+	spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_register_trans);
+
+/**
+ * v9fs_unregister_trans - unregister a 9p transport
+ * @m: the transport to remove
+ *
+ */
+void v9fs_unregister_trans(struct p9_trans_module *m)
+{
+	spin_lock(&v9fs_trans_lock);
+	list_del_init(&m->list);
+	spin_unlock(&v9fs_trans_lock);
+}
+EXPORT_SYMBOL(v9fs_unregister_trans);
+
+/**
+ * v9fs_get_trans_by_name - get transport with the matching name
+ * @name: string identifying transport
+ *
+ */
+struct p9_trans_module *v9fs_get_trans_by_name(char *s)
+{
+	struct p9_trans_module *t, *found = NULL;
+
+	spin_lock(&v9fs_trans_lock);
+
+	list_for_each_entry(t, &v9fs_trans_list, list)
+		if (strcmp(t->name, s) == 0 &&
+		    try_module_get(t->owner)) {
+			found = t;
+			break;
+		}
+
+	spin_unlock(&v9fs_trans_lock);
+	return found;
+}
+EXPORT_SYMBOL(v9fs_get_trans_by_name);
+
+/**
+ * v9fs_get_default_trans - get the default transport
+ *
+ */
+
+struct p9_trans_module *v9fs_get_default_trans(void)
+{
+	struct p9_trans_module *t, *found = NULL;
+
+	spin_lock(&v9fs_trans_lock);
+
+	list_for_each_entry(t, &v9fs_trans_list, list)
+		if (t->def && try_module_get(t->owner)) {
+			found = t;
+			break;
+		}
+
+	if (!found)
+		list_for_each_entry(t, &v9fs_trans_list, list)
+			if (try_module_get(t->owner)) {
+				found = t;
+				break;
+			}
+
+	spin_unlock(&v9fs_trans_lock);
+	return found;
+}
+EXPORT_SYMBOL(v9fs_get_default_trans);
+
+/**
+ * v9fs_put_trans - put trans
+ * @m: transport to put
+ *
+ */
+void v9fs_put_trans(struct p9_trans_module *m)
+{
+	if (m)
+		module_put(m->owner);
+}
+
+/**
+ * init_p9 - Initialize module
+ *
+ */
+static int __init init_p9(void)
+{
+	int ret = 0;
+
+	p9_error_init();
+	pr_info("Installing 9P2000 support\n");
+	p9_trans_fd_init();
+
+	return ret;
+}
+
+/**
+ * exit_p9 - shutdown module
+ *
+ */
+
+static void __exit exit_p9(void)
+{
+	pr_info("Unloading 9P2000 support\n");
+
+	p9_trans_fd_exit();
+}
+
+module_init(init_p9)
+module_exit(exit_p9)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");

addons/9p/src/4.4.180/protocol.c

@@ -0,0 +1,634 @@
+/*
+ * net/9p/protocol.c
+ *
+ * 9P Protocol Support Code
+ *
+ *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ *  Copyright (C) 2008 by IBM, Corp.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include "protocol.h"
+
+#include <trace/events/9p.h>
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+
+void p9stat_free(struct p9_wstat *stbuf)
+{
+	kfree(stbuf->name);
+	stbuf->name = NULL;
+	kfree(stbuf->uid);
+	stbuf->uid = NULL;
+	kfree(stbuf->gid);
+	stbuf->gid = NULL;
+	kfree(stbuf->muid);
+	stbuf->muid = NULL;
+	kfree(stbuf->extension);
+	stbuf->extension = NULL;
+}
+EXPORT_SYMBOL(p9stat_free);
+
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
+{
+	size_t len = min(pdu->size - pdu->offset, size);
+	memcpy(data, &pdu->sdata[pdu->offset], len);
+	pdu->offset += len;
+	return size - len;
+}
+
+static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
+{
+	size_t len = min(pdu->capacity - pdu->size, size);
+	memcpy(&pdu->sdata[pdu->size], data, len);
+	pdu->size += len;
+	return size - len;
+}
+
+static size_t
+pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)
+{
+	size_t len = min(pdu->capacity - pdu->size, size);
+	struct iov_iter i = *from;
+	if (copy_from_iter(&pdu->sdata[pdu->size], len, &i) != len)
+		len = 0;
+
+	pdu->size += len;
+	return size - len;
+}
+
+/*
+	b - int8_t
+	w - int16_t
+	d - int32_t
+	q - int64_t
+	s - string
+	u - numeric uid
+	g - numeric gid
+	S - stat
+	Q - qid
+	D - data blob (int32_t size followed by void *, results are not freed)
+	T - array of strings (int16_t count, followed by strings)
+	R - array of qids (int16_t count, followed by qids)
+	A - stat for 9p2000.L (p9_stat_dotl)
+	? - if optional = 1, continue parsing
+*/
+
+static int
+p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
+{
+	const char *ptr;
+	int errcode = 0;
+
+	for (ptr = fmt; *ptr; ptr++) {
+		switch (*ptr) {
+		case 'b':{
+				int8_t *val = va_arg(ap, int8_t *);
+				if (pdu_read(pdu, val, sizeof(*val))) {
+					errcode = -EFAULT;
+					break;
+				}
+			}
+			break;
+		case 'w':{
+				int16_t *val = va_arg(ap, int16_t *);
+				__le16 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le16_to_cpu(le_val);
+			}
+			break;
+		case 'd':{
+				int32_t *val = va_arg(ap, int32_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le32_to_cpu(le_val);
+			}
+			break;
+		case 'q':{
+				int64_t *val = va_arg(ap, int64_t *);
+				__le64 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*val = le64_to_cpu(le_val);
+			}
+			break;
+		case 's':{
+				char **sptr = va_arg(ap, char **);
+				uint16_t len;
+
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", &len);
+				if (errcode)
+					break;
+
+				*sptr = kmalloc(len + 1, GFP_NOFS);
+				if (*sptr == NULL) {
+					errcode = -EFAULT;
+					break;
+				}
+				if (pdu_read(pdu, *sptr, len)) {
+					errcode = -EFAULT;
+					kfree(*sptr);
+					*sptr = NULL;
+				} else
+					(*sptr)[len] = 0;
+			}
+			break;
+		case 'u': {
+				kuid_t *uid = va_arg(ap, kuid_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*uid = make_kuid(&init_user_ns,
+						 le32_to_cpu(le_val));
+			} break;
+		case 'g': {
+				kgid_t *gid = va_arg(ap, kgid_t *);
+				__le32 le_val;
+				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+					errcode = -EFAULT;
+					break;
+				}
+				*gid = make_kgid(&init_user_ns,
+						 le32_to_cpu(le_val));
+			} break;
+		case 'Q':{
+				struct p9_qid *qid =
+				    va_arg(ap, struct p9_qid *);
+
+				errcode = p9pdu_readf(pdu, proto_version, "bdq",
+						      &qid->type, &qid->version,
+						      &qid->path);
+			}
+			break;
+		case 'S':{
+				struct p9_wstat *stbuf =
+				    va_arg(ap, struct p9_wstat *);
+
+				memset(stbuf, 0, sizeof(struct p9_wstat));
+				stbuf->n_uid = stbuf->n_muid = INVALID_UID;
+				stbuf->n_gid = INVALID_GID;
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version,
+						"wwdQdddqssss?sugu",
+						&stbuf->size, &stbuf->type,
+						&stbuf->dev, &stbuf->qid,
+						&stbuf->mode, &stbuf->atime,
+						&stbuf->mtime, &stbuf->length,
+						&stbuf->name, &stbuf->uid,
+						&stbuf->gid, &stbuf->muid,
+						&stbuf->extension,
+						&stbuf->n_uid, &stbuf->n_gid,
+						&stbuf->n_muid);
+				if (errcode)
+					p9stat_free(stbuf);
+			}
+			break;
+		case 'D':{
+				uint32_t *count = va_arg(ap, uint32_t *);
+				void **data = va_arg(ap, void **);
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version, "d", count);
+				if (!errcode) {
+					*count =
+					    min_t(uint32_t, *count,
+						  pdu->size - pdu->offset);
+					*data = &pdu->sdata[pdu->offset];
+				}
+			}
+			break;
+		case 'T':{
+				uint16_t *nwname = va_arg(ap, uint16_t *);
+				char ***wnames = va_arg(ap, char ***);
+
+				errcode = p9pdu_readf(pdu, proto_version,
+								"w", nwname);
+				if (!errcode) {
+					*wnames =
+					    kmalloc(sizeof(char *) * *nwname,
+						    GFP_NOFS);
+					if (!*wnames)
+						errcode = -ENOMEM;
+				}
+
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < *nwname; i++) {
+						errcode =
+						    p9pdu_readf(pdu,
+								proto_version,
+								"s",
+								&(*wnames)[i]);
+						if (errcode)
+							break;
+					}
+				}
+
+				if (errcode) {
+					if (*wnames) {
+						int i;
+
+						for (i = 0; i < *nwname; i++)
+							kfree((*wnames)[i]);
+					}
+					kfree(*wnames);
+					*wnames = NULL;
+				}
+			}
+			break;
+		case 'R':{
+				uint16_t *nwqid = va_arg(ap, uint16_t *);
+				struct p9_qid **wqids =
+				    va_arg(ap, struct p9_qid **);
+
+				*wqids = NULL;
+
+				errcode =
+				    p9pdu_readf(pdu, proto_version, "w", nwqid);
+				if (!errcode) {
+					*wqids =
+					    kmalloc(*nwqid *
+						    sizeof(struct p9_qid),
+						    GFP_NOFS);
+					if (*wqids == NULL)
+						errcode = -ENOMEM;
+				}
+
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < *nwqid; i++) {
+						errcode =
+						    p9pdu_readf(pdu,
+								proto_version,
+								"Q",
+								&(*wqids)[i]);
+						if (errcode)
+							break;
+					}
+				}
+
+				if (errcode) {
+					kfree(*wqids);
+					*wqids = NULL;
+				}
+			}
+			break;
+		case 'A': {
+				struct p9_stat_dotl *stbuf =
+				    va_arg(ap, struct p9_stat_dotl *);
+
+				memset(stbuf, 0, sizeof(struct p9_stat_dotl));
+				errcode =
+				    p9pdu_readf(pdu, proto_version,
+					"qQdugqqqqqqqqqqqqqqq",
+					&stbuf->st_result_mask,
+					&stbuf->qid,
+					&stbuf->st_mode,
+					&stbuf->st_uid, &stbuf->st_gid,
+					&stbuf->st_nlink,
+					&stbuf->st_rdev, &stbuf->st_size,
+					&stbuf->st_blksize, &stbuf->st_blocks,
+					&stbuf->st_atime_sec,
+					&stbuf->st_atime_nsec,
+					&stbuf->st_mtime_sec,
+					&stbuf->st_mtime_nsec,
+					&stbuf->st_ctime_sec,
+					&stbuf->st_ctime_nsec,
+					&stbuf->st_btime_sec,
+					&stbuf->st_btime_nsec,
+					&stbuf->st_gen,
+					&stbuf->st_data_version);
+			}
+			break;
+		case '?':
+			if ((proto_version != p9_proto_2000u) &&
+				(proto_version != p9_proto_2000L))
+				return 0;
+			break;
+		default:
+			BUG();
+			break;
+		}
+
+		if (errcode)
+			break;
+	}
+
+	return errcode;
+}
+
+int
+p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+	va_list ap)
+{
+	const char *ptr;
+	int errcode = 0;
+
+	for (ptr = fmt; *ptr; ptr++) {
+		switch (*ptr) {
+		case 'b':{
+				int8_t val = va_arg(ap, int);
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'w':{
+				__le16 val = cpu_to_le16(va_arg(ap, int));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'd':{
+				__le32 val = cpu_to_le32(va_arg(ap, int32_t));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'q':{
+				__le64 val = cpu_to_le64(va_arg(ap, int64_t));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			}
+			break;
+		case 's':{
+				const char *sptr = va_arg(ap, const char *);
+				uint16_t len = 0;
+				if (sptr)
+					len = min_t(size_t, strlen(sptr),
+								USHRT_MAX);
+
+				errcode = p9pdu_writef(pdu, proto_version,
+								"w", len);
+				if (!errcode && pdu_write(pdu, sptr, len))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'u': {
+				kuid_t uid = va_arg(ap, kuid_t);
+				__le32 val = cpu_to_le32(
+						from_kuid(&init_user_ns, uid));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			} break;
+		case 'g': {
+				kgid_t gid = va_arg(ap, kgid_t);
+				__le32 val = cpu_to_le32(
+						from_kgid(&init_user_ns, gid));
+				if (pdu_write(pdu, &val, sizeof(val)))
+					errcode = -EFAULT;
+			} break;
+		case 'Q':{
+				const struct p9_qid *qid =
+				    va_arg(ap, const struct p9_qid *);
+				errcode =
+				    p9pdu_writef(pdu, proto_version, "bdq",
+						 qid->type, qid->version,
+						 qid->path);
+			} break;
+		case 'S':{
+				const struct p9_wstat *stbuf =
+				    va_arg(ap, const struct p9_wstat *);
+				errcode =
+				    p9pdu_writef(pdu, proto_version,
+						 "wwdQdddqssss?sugu",
+						 stbuf->size, stbuf->type,
+						 stbuf->dev, &stbuf->qid,
+						 stbuf->mode, stbuf->atime,
+						 stbuf->mtime, stbuf->length,
+						 stbuf->name, stbuf->uid,
+						 stbuf->gid, stbuf->muid,
+						 stbuf->extension, stbuf->n_uid,
+						 stbuf->n_gid, stbuf->n_muid);
+			} break;
+		case 'V':{
+				uint32_t count = va_arg(ap, uint32_t);
+				struct iov_iter *from =
+						va_arg(ap, struct iov_iter *);
+				errcode = p9pdu_writef(pdu, proto_version, "d",
+									count);
+				if (!errcode && pdu_write_u(pdu, from, count))
+					errcode = -EFAULT;
+			}
+			break;
+		case 'T':{
+				uint16_t nwname = va_arg(ap, int);
+				const char **wnames = va_arg(ap, const char **);
+
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwname);
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < nwname; i++) {
+						errcode =
+						    p9pdu_writef(pdu,
+								proto_version,
+								 "s",
+								 wnames[i]);
+						if (errcode)
+							break;
+					}
+				}
+			}
+			break;
+		case 'R':{
+				uint16_t nwqid = va_arg(ap, int);
+				struct p9_qid *wqids =
+				    va_arg(ap, struct p9_qid *);
+
+				errcode = p9pdu_writef(pdu, proto_version, "w",
+									nwqid);
+				if (!errcode) {
+					int i;
+
+					for (i = 0; i < nwqid; i++) {
+						errcode =
+						    p9pdu_writef(pdu,
+								proto_version,
+								 "Q",
+								 &wqids[i]);
+						if (errcode)
+							break;
+					}
+				}
+			}
+			break;
+		case 'I':{
+				struct p9_iattr_dotl *p9attr = va_arg(ap,
+							struct p9_iattr_dotl *);
+
+				errcode = p9pdu_writef(pdu, proto_version,
+							"ddugqqqqq",
+							p9attr->valid,
+							p9attr->mode,
+							p9attr->uid,
+							p9attr->gid,
+							p9attr->size,
+							p9attr->atime_sec,
+							p9attr->atime_nsec,
+							p9attr->mtime_sec,
+							p9attr->mtime_nsec);
+			}
+			break;
+		case '?':
+			if ((proto_version != p9_proto_2000u) &&
+				(proto_version != p9_proto_2000L))
+				return 0;
+			break;
+		default:
+			BUG();
+			break;
+		}
+
+		if (errcode)
+			break;
+	}
+
+	return errcode;
+}
+
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+
+int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
+{
+	struct p9_fcall fake_pdu;
+	int ret;
+
+	fake_pdu.size = len;
+	fake_pdu.capacity = len;
+	fake_pdu.sdata = buf;
+	fake_pdu.offset = 0;
+
+	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
+	if (ret) {
+		p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
+		trace_9p_protocol_dump(clnt, &fake_pdu);
+		return ret;
+	}
+
+	return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9stat_read);
+
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
+{
+	pdu->id = type;
+	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
+}
+
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
+{
+	int size = pdu->size;
+	int err;
+
+	pdu->size = 0;
+	err = p9pdu_writef(pdu, 0, "d", size);
+	pdu->size = size;
+
+	trace_9p_protocol_dump(clnt, pdu);
+	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
+		 pdu->size, pdu->id, pdu->tag);
+
+	return err;
+}
+
+void p9pdu_reset(struct p9_fcall *pdu)
+{
+	pdu->offset = 0;
+	pdu->size = 0;
+}
+
+int p9dirent_read(struct p9_client *clnt, char *buf, int len,
+		  struct p9_dirent *dirent)
+{
+	struct p9_fcall fake_pdu;
+	int ret;
+	char *nameptr;
+
+	fake_pdu.size = len;
+	fake_pdu.capacity = len;
+	fake_pdu.sdata = buf;
+	fake_pdu.offset = 0;
+
+	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
+			  &dirent->d_off, &dirent->d_type, &nameptr);
+	if (ret) {
+		p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
+		trace_9p_protocol_dump(clnt, &fake_pdu);
+		goto out;
+	}
+
+	strcpy(dirent->d_name, nameptr);
+	kfree(nameptr);
+
+out:
+	return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9dirent_read);

addons/9p/src/4.4.180/protocol.h

@@ -0,0 +1,34 @@
+/*
+ * net/9p/protocol.h
+ *
+ * 9P Protocol Support Code
+ *
+ *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ *  Copyright (C) 2008 by IBM, Corp.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+int p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+								va_list ap);
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type);
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu);
+void p9pdu_reset(struct p9_fcall *pdu);
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size);

addons/9p/src/4.4.180/trans_common.c

@@ -0,0 +1,29 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/mm.h>
+#include <linux/module.h>
+
+/**
+ *  p9_release_req_pages - Release pages after the transaction.
+ */
+void p9_release_pages(struct page **pages, int nr_pages)
+{
+	int i;
+
+	for (i = 0; i < nr_pages; i++)
+		if (pages[i])
+			put_page(pages[i]);
+}
+EXPORT_SYMBOL(p9_release_pages);

addons/9p/src/4.4.180/trans_common.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+void p9_release_pages(struct page **, int);

addons/9p/src/4.4.180/trans_rdma.c

@@ -0,0 +1,784 @@
+/*
+ * linux/fs/9p/trans_rdma.c
+ *
+ * RDMA transport layer based on the trans_fd.c implementation.
+ *
+ *  Copyright (C) 2008 by Tom Tucker <tom@opengridcomputing.com>
+ *  Copyright (C) 2006 by Russ Cox <rsc@swtch.com>
+ *  Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/in.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/kthread.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <linux/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/file.h>
+#include <linux/parser.h>
+#include <linux/semaphore.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/rdma_cm.h>
+
+#define P9_PORT			5640
+#define P9_RDMA_SQ_DEPTH	32
+#define P9_RDMA_RQ_DEPTH	32
+#define P9_RDMA_SEND_SGE	4
+#define P9_RDMA_RECV_SGE	4
+#define P9_RDMA_IRD		0
+#define P9_RDMA_ORD		0
+#define P9_RDMA_TIMEOUT		30000		/* 30 seconds */
+#define P9_RDMA_MAXSIZE		(1024*1024)	/* 1MB */
+
+/**
+ * struct p9_trans_rdma - RDMA transport instance
+ *
+ * @state: tracks the transport state machine for connection setup and tear down
+ * @cm_id: The RDMA CM ID
+ * @pd: Protection Domain pointer
+ * @qp: Queue Pair pointer
+ * @cq: Completion Queue pointer
+ * @dm_mr: DMA Memory Region pointer
+ * @lkey: The local access only memory region key
+ * @timeout: Number of uSecs to wait for connection management events
+ * @sq_depth: The depth of the Send Queue
+ * @sq_sem: Semaphore for the SQ
+ * @rq_depth: The depth of the Receive Queue.
+ * @rq_sem: Semaphore for the RQ
+ * @excess_rc : Amount of posted Receive Contexts without a pending request.
+ *		See rdma_request()
+ * @addr: The remote peer's address
+ * @req_lock: Protects the active request list
+ * @cm_done: Completion event for connection management tracking
+ */
+struct p9_trans_rdma {
+	enum {
+		P9_RDMA_INIT,
+		P9_RDMA_ADDR_RESOLVED,
+		P9_RDMA_ROUTE_RESOLVED,
+		P9_RDMA_CONNECTED,
+		P9_RDMA_FLUSHING,
+		P9_RDMA_CLOSING,
+		P9_RDMA_CLOSED,
+	} state;
+	struct rdma_cm_id *cm_id;
+	struct ib_pd *pd;
+	struct ib_qp *qp;
+	struct ib_cq *cq;
+	long timeout;
+	int sq_depth;
+	struct semaphore sq_sem;
+	int rq_depth;
+	struct semaphore rq_sem;
+	atomic_t excess_rc;
+	struct sockaddr_in addr;
+	spinlock_t req_lock;
+
+	struct completion cm_done;
+};
+
+/**
+ * p9_rdma_context - Keeps track of in-process WR
+ *
+ * @wc_op: The original WR op for when the CQE completes in error.
+ * @busa: Bus address to unmap when the WR completes
+ * @req: Keeps track of requests (send)
+ * @rc: Keepts track of replies (receive)
+ */
+struct p9_rdma_req;
+struct p9_rdma_context {
+	enum ib_wc_opcode wc_op;
+	dma_addr_t busa;
+	union {
+		struct p9_req_t *req;
+		struct p9_fcall *rc;
+	};
+};
+
+/**
+ * p9_rdma_opts - Collection of mount options
+ * @port: port of connection
+ * @sq_depth: The requested depth of the SQ. This really doesn't need
+ * to be any deeper than the number of threads used in the client
+ * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth
+ * @timeout: Time to wait in msecs for CM events
+ */
+struct p9_rdma_opts {
+	short port;
+	int sq_depth;
+	int rq_depth;
+	long timeout;
+	int privport;
+};
+
+/*
+ * Option Parsing (code inspired by NFS code)
+ */
+enum {
+	/* Options that take integer arguments */
+	Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout,
+	/* Options that take no argument */
+	Opt_privport,
+	Opt_err,
+};
+
+static match_table_t tokens = {
+	{Opt_port, "port=%u"},
+	{Opt_sq_depth, "sq=%u"},
+	{Opt_rq_depth, "rq=%u"},
+	{Opt_timeout, "timeout=%u"},
+	{Opt_privport, "privport"},
+	{Opt_err, NULL},
+};
+
+/**
+ * parse_opts - parse mount options into rdma options structure
+ * @params: options string passed from mount
+ * @opts: rdma transport-specific structure to parse options into
+ *
+ * Returns 0 upon success, -ERRNO upon failure
+ */
+static int parse_opts(char *params, struct p9_rdma_opts *opts)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int option;
+	char *options, *tmp_options;
+
+	opts->port = P9_PORT;
+	opts->sq_depth = P9_RDMA_SQ_DEPTH;
+	opts->rq_depth = P9_RDMA_RQ_DEPTH;
+	opts->timeout = P9_RDMA_TIMEOUT;
+	opts->privport = 0;
+
+	if (!params)
+		return 0;
+
+	tmp_options = kstrdup(params, GFP_KERNEL);
+	if (!tmp_options) {
+		p9_debug(P9_DEBUG_ERROR,
+			 "failed to allocate copy of option string\n");
+		return -ENOMEM;
+	}
+	options = tmp_options;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+		int r;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		if ((token != Opt_err) && (token != Opt_privport)) {
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				continue;
+			}
+		}
+		switch (token) {
+		case Opt_port:
+			opts->port = option;
+			break;
+		case Opt_sq_depth:
+			opts->sq_depth = option;
+			break;
+		case Opt_rq_depth:
+			opts->rq_depth = option;
+			break;
+		case Opt_timeout:
+			opts->timeout = option;
+			break;
+		case Opt_privport:
+			opts->privport = 1;
+			break;
+		default:
+			continue;
+		}
+	}
+	/* RQ must be at least as large as the SQ */
+	opts->rq_depth = max(opts->rq_depth, opts->sq_depth);
+	kfree(tmp_options);
+	return 0;
+}
+
+static int
+p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event)
+{
+	struct p9_client *c = id->context;
+	struct p9_trans_rdma *rdma = c->trans;
+	switch (event->event) {
+	case RDMA_CM_EVENT_ADDR_RESOLVED:
+		BUG_ON(rdma->state != P9_RDMA_INIT);
+		rdma->state = P9_RDMA_ADDR_RESOLVED;
+		break;
+
+	case RDMA_CM_EVENT_ROUTE_RESOLVED:
+		BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED);
+		rdma->state = P9_RDMA_ROUTE_RESOLVED;
+		break;
+
+	case RDMA_CM_EVENT_ESTABLISHED:
+		BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED);
+		rdma->state = P9_RDMA_CONNECTED;
+		break;
+
+	case RDMA_CM_EVENT_DISCONNECTED:
+		if (rdma)
+			rdma->state = P9_RDMA_CLOSED;
+		if (c)
+			c->status = Disconnected;
+		break;
+
+	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
+		break;
+
+	case RDMA_CM_EVENT_ADDR_CHANGE:
+	case RDMA_CM_EVENT_ROUTE_ERROR:
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+	case RDMA_CM_EVENT_MULTICAST_JOIN:
+	case RDMA_CM_EVENT_MULTICAST_ERROR:
+	case RDMA_CM_EVENT_REJECTED:
+	case RDMA_CM_EVENT_CONNECT_REQUEST:
+	case RDMA_CM_EVENT_CONNECT_RESPONSE:
+	case RDMA_CM_EVENT_CONNECT_ERROR:
+	case RDMA_CM_EVENT_ADDR_ERROR:
+	case RDMA_CM_EVENT_UNREACHABLE:
+		c->status = Disconnected;
+		rdma_disconnect(rdma->cm_id);
+		break;
+	default:
+		BUG();
+	}
+	complete(&rdma->cm_done);
+	return 0;
+}
+
+static void
+handle_recv(struct p9_client *client, struct p9_trans_rdma *rdma,
+	    struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len)
+{
+	struct p9_req_t *req;
+	int err = 0;
+	int16_t tag;
+
+	req = NULL;
+	ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize,
+							 DMA_FROM_DEVICE);
+
+	if (status != IB_WC_SUCCESS)
+		goto err_out;
+
+	err = p9_parse_header(c->rc, NULL, NULL, &tag, 1);
+	if (err)
+		goto err_out;
+
+	req = p9_tag_lookup(client, tag);
+	if (!req)
+		goto err_out;
+
+	/* Check that we have not yet received a reply for this request.
+	 */
+	if (unlikely(req->rc)) {
+		pr_err("Duplicate reply for request %d", tag);
+		goto err_out;
+	}
+
+	req->rc = c->rc;
+	p9_client_cb(client, req, REQ_STATUS_RCVD);
+
+	return;
+
+ err_out:
+	p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", req, err, status);
+	rdma->state = P9_RDMA_FLUSHING;
+	client->status = Disconnected;
+}
+
+static void
+handle_send(struct p9_client *client, struct p9_trans_rdma *rdma,
+	    struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len)
+{
+	ib_dma_unmap_single(rdma->cm_id->device,
+			    c->busa, c->req->tc->size,
+			    DMA_TO_DEVICE);
+}
+
+static void qp_event_handler(struct ib_event *event, void *context)
+{
+	p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n",
+		 event->event, context);
+}
+
+static void cq_comp_handler(struct ib_cq *cq, void *cq_context)
+{
+	struct p9_client *client = cq_context;
+	struct p9_trans_rdma *rdma = client->trans;
+	int ret;
+	struct ib_wc wc;
+
+	ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP);
+	while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) {
+		struct p9_rdma_context *c = (void *) (unsigned long) wc.wr_id;
+
+		switch (c->wc_op) {
+		case IB_WC_RECV:
+			handle_recv(client, rdma, c, wc.status, wc.byte_len);
+			up(&rdma->rq_sem);
+			break;
+
+		case IB_WC_SEND:
+			handle_send(client, rdma, c, wc.status, wc.byte_len);
+			up(&rdma->sq_sem);
+			break;
+
+		default:
+			pr_err("unexpected completion type, c->wc_op=%d, wc.opcode=%d, status=%d\n",
+			       c->wc_op, wc.opcode, wc.status);
+			break;
+		}
+		kfree(c);
+	}
+}
+
+static void cq_event_handler(struct ib_event *e, void *v)
+{
+	p9_debug(P9_DEBUG_ERROR, "CQ event %d context %p\n", e->event, v);
+}
+
+static void rdma_destroy_trans(struct p9_trans_rdma *rdma)
+{
+	if (!rdma)
+		return;
+
+	if (rdma->qp && !IS_ERR(rdma->qp))
+		ib_destroy_qp(rdma->qp);
+
+	if (rdma->pd && !IS_ERR(rdma->pd))
+		ib_dealloc_pd(rdma->pd);
+
+	if (rdma->cq && !IS_ERR(rdma->cq))
+		ib_destroy_cq(rdma->cq);
+
+	if (rdma->cm_id && !IS_ERR(rdma->cm_id))
+		rdma_destroy_id(rdma->cm_id);
+
+	kfree(rdma);
+}
+
+static int
+post_recv(struct p9_client *client, struct p9_rdma_context *c)
+{
+	struct p9_trans_rdma *rdma = client->trans;
+	struct ib_recv_wr wr, *bad_wr;
+	struct ib_sge sge;
+
+	c->busa = ib_dma_map_single(rdma->cm_id->device,
+				    c->rc->sdata, client->msize,
+				    DMA_FROM_DEVICE);
+	if (ib_dma_mapping_error(rdma->cm_id->device, c->busa))
+		goto error;
+
+	sge.addr = c->busa;
+	sge.length = client->msize;
+	sge.lkey = rdma->pd->local_dma_lkey;
+
+	wr.next = NULL;
+	c->wc_op = IB_WC_RECV;
+	wr.wr_id = (unsigned long) c;
+	wr.sg_list = &sge;
+	wr.num_sge = 1;
+	return ib_post_recv(rdma->qp, &wr, &bad_wr);
+
+ error:
+	p9_debug(P9_DEBUG_ERROR, "EIO\n");
+	return -EIO;
+}
+
+static int rdma_request(struct p9_client *client, struct p9_req_t *req)
+{
+	struct p9_trans_rdma *rdma = client->trans;
+	struct ib_send_wr wr, *bad_wr;
+	struct ib_sge sge;
+	int err = 0;
+	unsigned long flags;
+	struct p9_rdma_context *c = NULL;
+	struct p9_rdma_context *rpl_context = NULL;
+
+	/* When an error occurs between posting the recv and the send,
+	 * there will be a receive context posted without a pending request.
+	 * Since there is no way to "un-post" it, we remember it and skip
+	 * post_recv() for the next request.
+	 * So here,
+	 * see if we are this `next request' and need to absorb an excess rc.
+	 * If yes, then drop and free our own, and do not recv_post().
+	 **/
+	if (unlikely(atomic_read(&rdma->excess_rc) > 0)) {
+		if ((atomic_sub_return(1, &rdma->excess_rc) >= 0)) {
+			/* Got one ! */
+			kfree(req->rc);
+			req->rc = NULL;
+			goto dont_need_post_recv;
+		} else {
+			/* We raced and lost. */
+			atomic_inc(&rdma->excess_rc);
+		}
+	}
+
+	/* Allocate an fcall for the reply */
+	rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS);
+	if (!rpl_context) {
+		err = -ENOMEM;
+		goto recv_error;
+	}
+	rpl_context->rc = req->rc;
+
+	/*
+	 * Post a receive buffer for this request. We need to ensure
+	 * there is a reply buffer available for every outstanding
+	 * request. A flushed request can result in no reply for an
+	 * outstanding request, so we must keep a count to avoid
+	 * overflowing the RQ.
+	 */
+	if (down_interruptible(&rdma->rq_sem)) {
+		err = -EINTR;
+		goto recv_error;
+	}
+
+	err = post_recv(client, rpl_context);
+	if (err) {
+		p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n");
+		goto recv_error;
+	}
+	/* remove posted receive buffer from request structure */
+	req->rc = NULL;
+
+dont_need_post_recv:
+	/* Post the request */
+	c = kmalloc(sizeof *c, GFP_NOFS);
+	if (!c) {
+		err = -ENOMEM;
+		goto send_error;
+	}
+	c->req = req;
+
+	c->busa = ib_dma_map_single(rdma->cm_id->device,
+				    c->req->tc->sdata, c->req->tc->size,
+				    DMA_TO_DEVICE);
+	if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) {
+		err = -EIO;
+		goto send_error;
+	}
+
+	sge.addr = c->busa;
+	sge.length = c->req->tc->size;
+	sge.lkey = rdma->pd->local_dma_lkey;
+
+	wr.next = NULL;
+	c->wc_op = IB_WC_SEND;
+	wr.wr_id = (unsigned long) c;
+	wr.opcode = IB_WR_SEND;
+	wr.send_flags = IB_SEND_SIGNALED;
+	wr.sg_list = &sge;
+	wr.num_sge = 1;
+
+	if (down_interruptible(&rdma->sq_sem)) {
+		err = -EINTR;
+		goto send_error;
+	}
+
+	/* Mark request as `sent' *before* we actually send it,
+	 * because doing if after could erase the REQ_STATUS_RCVD
+	 * status in case of a very fast reply.
+	 */
+	req->status = REQ_STATUS_SENT;
+	err = ib_post_send(rdma->qp, &wr, &bad_wr);
+	if (err)
+		goto send_error;
+
+	/* Success */
+	return 0;
+
+ /* Handle errors that happened during or while preparing the send: */
+ send_error:
+	req->status = REQ_STATUS_ERROR;
+	kfree(c);
+	p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err);
+
+	/* Ach.
+	 *  We did recv_post(), but not send. We have one recv_post in excess.
+	 */
+	atomic_inc(&rdma->excess_rc);
+	return err;
+
+ /* Handle errors that happened during or while preparing post_recv(): */
+ recv_error:
+	kfree(rpl_context);
+	spin_lock_irqsave(&rdma->req_lock, flags);
+	if (rdma->state < P9_RDMA_CLOSING) {
+		rdma->state = P9_RDMA_CLOSING;
+		spin_unlock_irqrestore(&rdma->req_lock, flags);
+		rdma_disconnect(rdma->cm_id);
+	} else
+		spin_unlock_irqrestore(&rdma->req_lock, flags);
+	return err;
+}
+
+static void rdma_close(struct p9_client *client)
+{
+	struct p9_trans_rdma *rdma;
+
+	if (!client)
+		return;
+
+	rdma = client->trans;
+	if (!rdma)
+		return;
+
+	client->status = Disconnected;
+	rdma_disconnect(rdma->cm_id);
+	rdma_destroy_trans(rdma);
+}
+
+/**
+ * alloc_rdma - Allocate and initialize the rdma transport structure
+ * @opts: Mount options structure
+ */
+static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts)
+{
+	struct p9_trans_rdma *rdma;
+
+	rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL);
+	if (!rdma)
+		return NULL;
+
+	rdma->sq_depth = opts->sq_depth;
+	rdma->rq_depth = opts->rq_depth;
+	rdma->timeout = opts->timeout;
+	spin_lock_init(&rdma->req_lock);
+	init_completion(&rdma->cm_done);
+	sema_init(&rdma->sq_sem, rdma->sq_depth);
+	sema_init(&rdma->rq_sem, rdma->rq_depth);
+	atomic_set(&rdma->excess_rc, 0);
+
+	return rdma;
+}
+
+static int rdma_cancel(struct p9_client *client, struct p9_req_t *req)
+{
+	/* Nothing to do here.
+	 * We will take care of it (if we have to) in rdma_cancelled()
+	 */
+	return 1;
+}
+
+/* A request has been fully flushed without a reply.
+ * That means we have posted one buffer in excess.
+ */
+static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req)
+{
+	struct p9_trans_rdma *rdma = client->trans;
+	atomic_inc(&rdma->excess_rc);
+	return 0;
+}
+
+static int p9_rdma_bind_privport(struct p9_trans_rdma *rdma)
+{
+	struct sockaddr_in cl = {
+		.sin_family = AF_INET,
+		.sin_addr.s_addr = htonl(INADDR_ANY),
+	};
+	int port, err = -EINVAL;
+
+	for (port = P9_DEF_MAX_RESVPORT; port >= P9_DEF_MIN_RESVPORT; port--) {
+		cl.sin_port = htons((ushort)port);
+		err = rdma_bind_addr(rdma->cm_id, (struct sockaddr *)&cl);
+		if (err != -EADDRINUSE)
+			break;
+	}
+	return err;
+}
+
+/**
+ * trans_create_rdma - Transport method for creating atransport instance
+ * @client: client instance
+ * @addr: IP address string
+ * @args: Mount options string
+ */
+static int
+rdma_create_trans(struct p9_client *client, const char *addr, char *args)
+{
+	int err;
+	struct p9_rdma_opts opts;
+	struct p9_trans_rdma *rdma;
+	struct rdma_conn_param conn_param;
+	struct ib_qp_init_attr qp_attr;
+	struct ib_cq_init_attr cq_attr = {};
+
+	if (addr == NULL)
+		return -EINVAL;
+
+	/* Parse the transport specific mount options */
+	err = parse_opts(args, &opts);
+	if (err < 0)
+		return err;
+
+	/* Create and initialize the RDMA transport structure */
+	rdma = alloc_rdma(&opts);
+	if (!rdma)
+		return -ENOMEM;
+
+	/* Create the RDMA CM ID */
+	rdma->cm_id = rdma_create_id(&init_net, p9_cm_event_handler, client,
+				     RDMA_PS_TCP, IB_QPT_RC);
+	if (IS_ERR(rdma->cm_id))
+		goto error;
+
+	/* Associate the client with the transport */
+	client->trans = rdma;
+
+	/* Bind to a privileged port if we need to */
+	if (opts.privport) {
+		err = p9_rdma_bind_privport(rdma);
+		if (err < 0) {
+			pr_err("%s (%d): problem binding to privport: %d\n",
+			       __func__, task_pid_nr(current), -err);
+			goto error;
+		}
+	}
+
+	/* Resolve the server's address */
+	rdma->addr.sin_family = AF_INET;
+	rdma->addr.sin_addr.s_addr = in_aton(addr);
+	rdma->addr.sin_port = htons(opts.port);
+	err = rdma_resolve_addr(rdma->cm_id, NULL,
+				(struct sockaddr *)&rdma->addr,
+				rdma->timeout);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_ADDR_RESOLVED))
+		goto error;
+
+	/* Resolve the route to the server */
+	err = rdma_resolve_route(rdma->cm_id, rdma->timeout);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_ROUTE_RESOLVED))
+		goto error;
+
+	/* Create the Completion Queue */
+	cq_attr.cqe = opts.sq_depth + opts.rq_depth + 1;
+	rdma->cq = ib_create_cq(rdma->cm_id->device, cq_comp_handler,
+				cq_event_handler, client,
+				&cq_attr);
+	if (IS_ERR(rdma->cq))
+		goto error;
+	ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP);
+
+	/* Create the Protection Domain */
+	rdma->pd = ib_alloc_pd(rdma->cm_id->device);
+	if (IS_ERR(rdma->pd))
+		goto error;
+
+	/* Create the Queue Pair */
+	memset(&qp_attr, 0, sizeof qp_attr);
+	qp_attr.event_handler = qp_event_handler;
+	qp_attr.qp_context = client;
+	qp_attr.cap.max_send_wr = opts.sq_depth;
+	qp_attr.cap.max_recv_wr = opts.rq_depth;
+	qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE;
+	qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE;
+	qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+	qp_attr.qp_type = IB_QPT_RC;
+	qp_attr.send_cq = rdma->cq;
+	qp_attr.recv_cq = rdma->cq;
+	err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr);
+	if (err)
+		goto error;
+	rdma->qp = rdma->cm_id->qp;
+
+	/* Request a connection */
+	memset(&conn_param, 0, sizeof(conn_param));
+	conn_param.private_data = NULL;
+	conn_param.private_data_len = 0;
+	conn_param.responder_resources = P9_RDMA_IRD;
+	conn_param.initiator_depth = P9_RDMA_ORD;
+	err = rdma_connect(rdma->cm_id, &conn_param);
+	if (err)
+		goto error;
+	err = wait_for_completion_interruptible(&rdma->cm_done);
+	if (err || (rdma->state != P9_RDMA_CONNECTED))
+		goto error;
+
+	client->status = Connected;
+
+	return 0;
+
+error:
+	rdma_destroy_trans(rdma);
+	return -ENOTCONN;
+}
+
+static struct p9_trans_module p9_rdma_trans = {
+	.name = "rdma",
+	.maxsize = P9_RDMA_MAXSIZE,
+	.def = 0,
+	.owner = THIS_MODULE,
+	.create = rdma_create_trans,
+	.close = rdma_close,
+	.request = rdma_request,
+	.cancel = rdma_cancel,
+	.cancelled = rdma_cancelled,
+};
+
+/**
+ * p9_trans_rdma_init - Register the 9P RDMA transport driver
+ */
+static int __init p9_trans_rdma_init(void)
+{
+	v9fs_register_trans(&p9_rdma_trans);
+	return 0;
+}
+
+static void __exit p9_trans_rdma_exit(void)
+{
+	v9fs_unregister_trans(&p9_rdma_trans);
+}
+
+module_init(p9_trans_rdma_init);
+module_exit(p9_trans_rdma_exit);
+
+MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>");
+MODULE_DESCRIPTION("RDMA Transport for 9P");
+MODULE_LICENSE("Dual BSD/GPL");

addons/9p/src/4.4.180/trans_virtio.c

@@ -0,0 +1,788 @@
+/*
+ * The Virtio 9p transport driver
+ *
+ * This is a block based transport driver based on the lguest block driver
+ * code.
+ *
+ *  Copyright (C) 2007, 2008 Eric Van Hensbergen, IBM Corporation
+ *
+ *  Based on virtio console driver
+ *  Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/in.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/un.h>
+#include <linux/uaccess.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/file.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <linux/parser.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include <linux/scatterlist.h>
+#include <linux/swap.h>
+#include <linux/virtio.h>
+#include <linux/virtio_9p.h>
+#include "trans_common.h"
+
+#define VIRTQUEUE_NUM	128
+
+/* a single mutex to manage channel initialization and attachment */
+static DEFINE_MUTEX(virtio_9p_lock);
+static DECLARE_WAIT_QUEUE_HEAD(vp_wq);
+static atomic_t vp_pinned = ATOMIC_INIT(0);
+
+/**
+ * struct virtio_chan - per-instance transport information
+ * @initialized: whether the channel is initialized
+ * @inuse: whether the channel is in use
+ * @lock: protects multiple elements within this structure
+ * @client: client instance
+ * @vdev: virtio dev associated with this channel
+ * @vq: virtio queue associated with this channel
+ * @sg: scatter gather list which is used to pack a request (protected?)
+ *
+ * We keep all per-channel information in a structure.
+ * This structure is allocated within the devices dev->mem space.
+ * A pointer to the structure will get put in the transport private.
+ *
+ */
+
+struct virtio_chan {
+	bool inuse;
+
+	spinlock_t lock;
+
+	struct p9_client *client;
+	struct virtio_device *vdev;
+	struct virtqueue *vq;
+	int ring_bufs_avail;
+	wait_queue_head_t *vc_wq;
+	/* This is global limit. Since we don't have a global structure,
+	 * will be placing it in each channel.
+	 */
+	unsigned long p9_max_pages;
+	/* Scatterlist: can be too big for stack. */
+	struct scatterlist sg[VIRTQUEUE_NUM];
+
+	int tag_len;
+	/*
+	 * tag name to identify a mount Non-null terminated
+	 */
+	char *tag;
+
+	struct list_head chan_list;
+};
+
+static struct list_head virtio_chan_list;
+
+/* How many bytes left in this page. */
+static unsigned int rest_of_page(void *data)
+{
+	return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE);
+}
+
+/**
+ * p9_virtio_close - reclaim resources of a channel
+ * @client: client instance
+ *
+ * This reclaims a channel by freeing its resources and
+ * reseting its inuse flag.
+ *
+ */
+
+static void p9_virtio_close(struct p9_client *client)
+{
+	struct virtio_chan *chan = client->trans;
+
+	mutex_lock(&virtio_9p_lock);
+	if (chan)
+		chan->inuse = false;
+	mutex_unlock(&virtio_9p_lock);
+}
+
+/**
+ * req_done - callback which signals activity from the server
+ * @vq: virtio queue activity was received on
+ *
+ * This notifies us that the server has triggered some activity
+ * on the virtio channel - most likely a response to request we
+ * sent.  Figure out which requests now have responses and wake up
+ * those threads.
+ *
+ * Bugs: could do with some additional sanity checking, but appears to work.
+ *
+ */
+
+static void req_done(struct virtqueue *vq)
+{
+	struct virtio_chan *chan = vq->vdev->priv;
+	struct p9_fcall *rc;
+	unsigned int len;
+	struct p9_req_t *req;
+	unsigned long flags;
+
+	p9_debug(P9_DEBUG_TRANS, ": request done\n");
+
+	while (1) {
+		spin_lock_irqsave(&chan->lock, flags);
+		rc = virtqueue_get_buf(chan->vq, &len);
+		if (rc == NULL) {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			break;
+		}
+		chan->ring_bufs_avail = 1;
+		spin_unlock_irqrestore(&chan->lock, flags);
+		/* Wakeup if anyone waiting for VirtIO ring space. */
+		wake_up(chan->vc_wq);
+		p9_debug(P9_DEBUG_TRANS, ": rc %p\n", rc);
+		p9_debug(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag);
+		req = p9_tag_lookup(chan->client, rc->tag);
+		p9_client_cb(chan->client, req, REQ_STATUS_RCVD);
+	}
+}
+
+/**
+ * pack_sg_list - pack a scatter gather list from a linear buffer
+ * @sg: scatter/gather list to pack into
+ * @start: which segment of the sg_list to start at
+ * @limit: maximum segment to pack data to
+ * @data: data to pack into scatter/gather list
+ * @count: amount of data to pack into the scatter/gather list
+ *
+ * sg_lists have multiple segments of various sizes.  This will pack
+ * arbitrary data into an existing scatter gather list, segmenting the
+ * data as necessary within constraints.
+ *
+ */
+
+static int pack_sg_list(struct scatterlist *sg, int start,
+			int limit, char *data, int count)
+{
+	int s;
+	int index = start;
+
+	while (count) {
+		s = rest_of_page(data);
+		if (s > count)
+			s = count;
+		BUG_ON(index >= limit);
+		/* Make sure we don't terminate early. */
+		sg_unmark_end(&sg[index]);
+		sg_set_buf(&sg[index++], data, s);
+		count -= s;
+		data += s;
+	}
+	if (index-start)
+		sg_mark_end(&sg[index - 1]);
+	return index-start;
+}
+
+/* We don't currently allow canceling of virtio requests */
+static int p9_virtio_cancel(struct p9_client *client, struct p9_req_t *req)
+{
+	return 1;
+}
+
+/**
+ * pack_sg_list_p - Just like pack_sg_list. Instead of taking a buffer,
+ * this takes a list of pages.
+ * @sg: scatter/gather list to pack into
+ * @start: which segment of the sg_list to start at
+ * @pdata: a list of pages to add into sg.
+ * @nr_pages: number of pages to pack into the scatter/gather list
+ * @offs: amount of data in the beginning of first page _not_ to pack
+ * @count: amount of data to pack into the scatter/gather list
+ */
+static int
+pack_sg_list_p(struct scatterlist *sg, int start, int limit,
+	       struct page **pdata, int nr_pages, size_t offs, int count)
+{
+	int i = 0, s;
+	int data_off = offs;
+	int index = start;
+
+	BUG_ON(nr_pages > (limit - start));
+	/*
+	 * if the first page doesn't start at
+	 * page boundary find the offset
+	 */
+	while (nr_pages) {
+		s = PAGE_SIZE - data_off;
+		if (s > count)
+			s = count;
+		BUG_ON(index >= limit);
+		/* Make sure we don't terminate early. */
+		sg_unmark_end(&sg[index]);
+		sg_set_page(&sg[index++], pdata[i++], s, data_off);
+		data_off = 0;
+		count -= s;
+		nr_pages--;
+	}
+
+	if (index-start)
+		sg_mark_end(&sg[index - 1]);
+	return index - start;
+}
+
+/**
+ * p9_virtio_request - issue a request
+ * @client: client instance issuing the request
+ * @req: request to be issued
+ *
+ */
+
+static int
+p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
+{
+	int err;
+	int in, out, out_sgs, in_sgs;
+	unsigned long flags;
+	struct virtio_chan *chan = client->trans;
+	struct scatterlist *sgs[2];
+
+	p9_debug(P9_DEBUG_TRANS, "9p debug: virtio request\n");
+
+	req->status = REQ_STATUS_SENT;
+req_retry:
+	spin_lock_irqsave(&chan->lock, flags);
+
+	out_sgs = in_sgs = 0;
+	/* Handle out VirtIO ring buffers */
+	out = pack_sg_list(chan->sg, 0,
+			   VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
+	if (out)
+		sgs[out_sgs++] = chan->sg;
+
+	in = pack_sg_list(chan->sg, out,
+			  VIRTQUEUE_NUM, req->rc->sdata, req->rc->capacity);
+	if (in)
+		sgs[out_sgs + in_sgs++] = chan->sg + out;
+
+	err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
+				GFP_ATOMIC);
+	if (err < 0) {
+		if (err == -ENOSPC) {
+			chan->ring_bufs_avail = 0;
+			spin_unlock_irqrestore(&chan->lock, flags);
+			err = wait_event_killable(*chan->vc_wq,
+						  chan->ring_bufs_avail);
+			if (err  == -ERESTARTSYS)
+				return err;
+
+			p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n");
+			goto req_retry;
+		} else {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			p9_debug(P9_DEBUG_TRANS,
+				 "virtio rpc add_sgs returned failure\n");
+			return -EIO;
+		}
+	}
+	virtqueue_kick(chan->vq);
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
+	return 0;
+}
+
+static int p9_get_mapped_pages(struct virtio_chan *chan,
+			       struct page ***pages,
+			       struct iov_iter *data,
+			       int count,
+			       size_t *offs,
+			       int *need_drop)
+{
+	int nr_pages;
+	int err;
+
+	if (!iov_iter_count(data))
+		return 0;
+
+	if (!(data->type & ITER_KVEC)) {
+		int n;
+		/*
+		 * We allow only p9_max_pages pinned. We wait for the
+		 * Other zc request to finish here
+		 */
+		if (atomic_read(&vp_pinned) >= chan->p9_max_pages) {
+			err = wait_event_killable(vp_wq,
+			      (atomic_read(&vp_pinned) < chan->p9_max_pages));
+			if (err == -ERESTARTSYS)
+				return err;
+		}
+		n = iov_iter_get_pages_alloc(data, pages, count, offs);
+		if (n < 0)
+			return n;
+		*need_drop = 1;
+		nr_pages = DIV_ROUND_UP(n + *offs, PAGE_SIZE);
+		atomic_add(nr_pages, &vp_pinned);
+		return n;
+	} else {
+		/* kernel buffer, no need to pin pages */
+		int index;
+		size_t len;
+		void *p;
+
+		/* we'd already checked that it's non-empty */
+		while (1) {
+			len = iov_iter_single_seg_count(data);
+			if (likely(len)) {
+				p = data->kvec->iov_base + data->iov_offset;
+				break;
+			}
+			iov_iter_advance(data, 0);
+		}
+		if (len > count)
+			len = count;
+
+		nr_pages = DIV_ROUND_UP((unsigned long)p + len, PAGE_SIZE) -
+			   (unsigned long)p / PAGE_SIZE;
+
+		*pages = kmalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
+		if (!*pages)
+			return -ENOMEM;
+
+		*need_drop = 0;
+		p -= (*offs = (unsigned long)p % PAGE_SIZE);
+		for (index = 0; index < nr_pages; index++) {
+			if (is_vmalloc_addr(p))
+				(*pages)[index] = vmalloc_to_page(p);
+			else
+				(*pages)[index] = kmap_to_page(p);
+			p += PAGE_SIZE;
+		}
+		return len;
+	}
+}
+
+/**
+ * p9_virtio_zc_request - issue a zero copy request
+ * @client: client instance issuing the request
+ * @req: request to be issued
+ * @uidata: user bffer that should be ued for zero copy read
+ * @uodata: user buffer that shoud be user for zero copy write
+ * @inlen: read buffer size
+ * @olen: write buffer size
+ * @hdrlen: reader header size, This is the size of response protocol data
+ *
+ */
+static int
+p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
+		     struct iov_iter *uidata, struct iov_iter *uodata,
+		     int inlen, int outlen, int in_hdr_len)
+{
+	int in, out, err, out_sgs, in_sgs;
+	unsigned long flags;
+	int in_nr_pages = 0, out_nr_pages = 0;
+	struct page **in_pages = NULL, **out_pages = NULL;
+	struct virtio_chan *chan = client->trans;
+	struct scatterlist *sgs[4];
+	size_t offs;
+	int need_drop = 0;
+
+	p9_debug(P9_DEBUG_TRANS, "virtio request\n");
+
+	if (uodata) {
+		__le32 sz;
+		int n = p9_get_mapped_pages(chan, &out_pages, uodata,
+					    outlen, &offs, &need_drop);
+		if (n < 0)
+			return n;
+		out_nr_pages = DIV_ROUND_UP(n + offs, PAGE_SIZE);
+		if (n != outlen) {
+			__le32 v = cpu_to_le32(n);
+			memcpy(&req->tc->sdata[req->tc->size - 4], &v, 4);
+			outlen = n;
+		}
+		/* The size field of the message must include the length of the
+		 * header and the length of the data.  We didn't actually know
+		 * the length of the data until this point so add it in now.
+		 */
+		sz = cpu_to_le32(req->tc->size + outlen);
+		memcpy(&req->tc->sdata[0], &sz, sizeof(sz));
+	} else if (uidata) {
+		int n = p9_get_mapped_pages(chan, &in_pages, uidata,
+					    inlen, &offs, &need_drop);
+		if (n < 0)
+			return n;
+		in_nr_pages = DIV_ROUND_UP(n + offs, PAGE_SIZE);
+		if (n != inlen) {
+			__le32 v = cpu_to_le32(n);
+			memcpy(&req->tc->sdata[req->tc->size - 4], &v, 4);
+			inlen = n;
+		}
+	}
+	req->status = REQ_STATUS_SENT;
+req_retry_pinned:
+	spin_lock_irqsave(&chan->lock, flags);
+
+	out_sgs = in_sgs = 0;
+
+	/* out data */
+	out = pack_sg_list(chan->sg, 0,
+			   VIRTQUEUE_NUM, req->tc->sdata, req->tc->size);
+
+	if (out)
+		sgs[out_sgs++] = chan->sg;
+
+	if (out_pages) {
+		sgs[out_sgs++] = chan->sg + out;
+		out += pack_sg_list_p(chan->sg, out, VIRTQUEUE_NUM,
+				      out_pages, out_nr_pages, offs, outlen);
+	}
+		
+	/*
+	 * Take care of in data
+	 * For example TREAD have 11.
+	 * 11 is the read/write header = PDU Header(7) + IO Size (4).
+	 * Arrange in such a way that server places header in the
+	 * alloced memory and payload onto the user buffer.
+	 */
+	in = pack_sg_list(chan->sg, out,
+			  VIRTQUEUE_NUM, req->rc->sdata, in_hdr_len);
+	if (in)
+		sgs[out_sgs + in_sgs++] = chan->sg + out;
+
+	if (in_pages) {
+		sgs[out_sgs + in_sgs++] = chan->sg + out + in;
+		in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
+				     in_pages, in_nr_pages, offs, inlen);
+	}
+
+	BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs));
+	err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc,
+				GFP_ATOMIC);
+	if (err < 0) {
+		if (err == -ENOSPC) {
+			chan->ring_bufs_avail = 0;
+			spin_unlock_irqrestore(&chan->lock, flags);
+			err = wait_event_killable(*chan->vc_wq,
+						  chan->ring_bufs_avail);
+			if (err  == -ERESTARTSYS)
+				goto err_out;
+
+			p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n");
+			goto req_retry_pinned;
+		} else {
+			spin_unlock_irqrestore(&chan->lock, flags);
+			p9_debug(P9_DEBUG_TRANS,
+				 "virtio rpc add_sgs returned failure\n");
+			err = -EIO;
+			goto err_out;
+		}
+	}
+	virtqueue_kick(chan->vq);
+	spin_unlock_irqrestore(&chan->lock, flags);
+	p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
+	err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
+	/*
+	 * Non kernel buffers are pinned, unpin them
+	 */
+err_out:
+	if (need_drop) {
+		if (in_pages) {
+			p9_release_pages(in_pages, in_nr_pages);
+			atomic_sub(in_nr_pages, &vp_pinned);
+		}
+		if (out_pages) {
+			p9_release_pages(out_pages, out_nr_pages);
+			atomic_sub(out_nr_pages, &vp_pinned);
+		}
+		/* wakeup anybody waiting for slots to pin pages */
+		wake_up(&vp_wq);
+	}
+	kfree(in_pages);
+	kfree(out_pages);
+	return err;
+}
+
+static ssize_t p9_mount_tag_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct virtio_chan *chan;
+	struct virtio_device *vdev;
+
+	vdev = dev_to_virtio(dev);
+	chan = vdev->priv;
+
+	memcpy(buf, chan->tag, chan->tag_len);
+	buf[chan->tag_len] = 0;
+
+	return chan->tag_len + 1;
+}
+
+static DEVICE_ATTR(mount_tag, 0444, p9_mount_tag_show, NULL);
+
+/**
+ * p9_virtio_probe - probe for existence of 9P virtio channels
+ * @vdev: virtio device to probe
+ *
+ * This probes for existing virtio channels.
+ *
+ */
+
+static int p9_virtio_probe(struct virtio_device *vdev)
+{
+	__u16 tag_len;
+	char *tag;
+	int err;
+	struct virtio_chan *chan;
+
+	if (!vdev->config->get) {
+		dev_err(&vdev->dev, "%s failure: config access disabled\n",
+			__func__);
+		return -EINVAL;
+	}
+
+	chan = kmalloc(sizeof(struct virtio_chan), GFP_KERNEL);
+	if (!chan) {
+		pr_err("Failed to allocate virtio 9P channel\n");
+		err = -ENOMEM;
+		goto fail;
+	}
+
+	chan->vdev = vdev;
+
+	/* We expect one virtqueue, for requests. */
+	chan->vq = virtio_find_single_vq(vdev, req_done, "requests");
+	if (IS_ERR(chan->vq)) {
+		err = PTR_ERR(chan->vq);
+		goto out_free_chan;
+	}
+	chan->vq->vdev->priv = chan;
+	spin_lock_init(&chan->lock);
+
+	sg_init_table(chan->sg, VIRTQUEUE_NUM);
+
+	chan->inuse = false;
+	if (virtio_has_feature(vdev, VIRTIO_9P_MOUNT_TAG)) {
+		virtio_cread(vdev, struct virtio_9p_config, tag_len, &tag_len);
+	} else {
+		err = -EINVAL;
+		goto out_free_vq;
+	}
+	tag = kmalloc(tag_len, GFP_KERNEL);
+	if (!tag) {
+		err = -ENOMEM;
+		goto out_free_vq;
+	}
+
+	virtio_cread_bytes(vdev, offsetof(struct virtio_9p_config, tag),
+			   tag, tag_len);
+	chan->tag = tag;
+	chan->tag_len = tag_len;
+	err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
+	if (err) {
+		goto out_free_tag;
+	}
+	chan->vc_wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
+	if (!chan->vc_wq) {
+		err = -ENOMEM;
+		goto out_free_tag;
+	}
+	init_waitqueue_head(chan->vc_wq);
+	chan->ring_bufs_avail = 1;
+	/* Ceiling limit to avoid denial of service attacks */
+	chan->p9_max_pages = nr_free_buffer_pages()/4;
+
+	virtio_device_ready(vdev);
+
+	mutex_lock(&virtio_9p_lock);
+	list_add_tail(&chan->chan_list, &virtio_chan_list);
+	mutex_unlock(&virtio_9p_lock);
+
+	/* Let udev rules use the new mount_tag attribute. */
+	kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE);
+
+	return 0;
+
+out_free_tag:
+	kfree(tag);
+out_free_vq:
+	vdev->config->del_vqs(vdev);
+out_free_chan:
+	kfree(chan);
+fail:
+	return err;
+}
+
+
+/**
+ * p9_virtio_create - allocate a new virtio channel
+ * @client: client instance invoking this transport
+ * @devname: string identifying the channel to connect to (unused)
+ * @args: args passed from sys_mount() for per-transport options (unused)
+ *
+ * This sets up a transport channel for 9p communication.  Right now
+ * we only match the first available channel, but eventually we couldlook up
+ * alternate channels by matching devname versus a virtio_config entry.
+ * We use a simple reference count mechanism to ensure that only a single
+ * mount has a channel open at a time.
+ *
+ */
+
+static int
+p9_virtio_create(struct p9_client *client, const char *devname, char *args)
+{
+	struct virtio_chan *chan;
+	int ret = -ENOENT;
+	int found = 0;
+
+	if (devname == NULL)
+		return -EINVAL;
+
+	mutex_lock(&virtio_9p_lock);
+	list_for_each_entry(chan, &virtio_chan_list, chan_list) {
+		if (!strncmp(devname, chan->tag, chan->tag_len) &&
+		    strlen(devname) == chan->tag_len) {
+			if (!chan->inuse) {
+				chan->inuse = true;
+				found = 1;
+				break;
+			}
+			ret = -EBUSY;
+		}
+	}
+	mutex_unlock(&virtio_9p_lock);
+
+	if (!found) {
+		pr_err("no channels available\n");
+		return ret;
+	}
+
+	client->trans = (void *)chan;
+	client->status = Connected;
+	chan->client = client;
+
+	return 0;
+}
+
+/**
+ * p9_virtio_remove - clean up resources associated with a virtio device
+ * @vdev: virtio device to remove
+ *
+ */
+
+static void p9_virtio_remove(struct virtio_device *vdev)
+{
+	struct virtio_chan *chan = vdev->priv;
+	unsigned long warning_time;
+
+	mutex_lock(&virtio_9p_lock);
+
+	/* Remove self from list so we don't get new users. */
+	list_del(&chan->chan_list);
+	warning_time = jiffies;
+
+	/* Wait for existing users to close. */
+	while (chan->inuse) {
+		mutex_unlock(&virtio_9p_lock);
+		msleep(250);
+		if (time_after(jiffies, warning_time + 10 * HZ)) {
+			dev_emerg(&vdev->dev,
+				  "p9_virtio_remove: waiting for device in use.\n");
+			warning_time = jiffies;
+		}
+		mutex_lock(&virtio_9p_lock);
+	}
+
+	mutex_unlock(&virtio_9p_lock);
+
+	vdev->config->reset(vdev);
+	vdev->config->del_vqs(vdev);
+
+	sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
+	kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE);
+	kfree(chan->tag);
+	kfree(chan->vc_wq);
+	kfree(chan);
+
+}
+
+static struct virtio_device_id id_table[] = {
+	{ VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID },
+	{ 0 },
+};
+
+static unsigned int features[] = {
+	VIRTIO_9P_MOUNT_TAG,
+};
+
+/* The standard "struct lguest_driver": */
+static struct virtio_driver p9_virtio_drv = {
+	.feature_table  = features,
+	.feature_table_size = ARRAY_SIZE(features),
+	.driver.name    = KBUILD_MODNAME,
+	.driver.owner	= THIS_MODULE,
+	.id_table	= id_table,
+	.probe		= p9_virtio_probe,
+	.remove		= p9_virtio_remove,
+};
+
+static struct p9_trans_module p9_virtio_trans = {
+	.name = "virtio",
+	.create = p9_virtio_create,
+	.close = p9_virtio_close,
+	.request = p9_virtio_request,
+	.zc_request = p9_virtio_zc_request,
+	.cancel = p9_virtio_cancel,
+	/*
+	 * We leave one entry for input and one entry for response
+	 * headers. We also skip one more entry to accomodate, address
+	 * that are not at page boundary, that can result in an extra
+	 * page in zero copy.
+	 */
+	.maxsize = PAGE_SIZE * (VIRTQUEUE_NUM - 3),
+	.def = 1,
+	.owner = THIS_MODULE,
+};
+
+/* The standard init function */
+static int __init p9_virtio_init(void)
+{
+	INIT_LIST_HEAD(&virtio_chan_list);
+
+	v9fs_register_trans(&p9_virtio_trans);
+	return register_virtio_driver(&p9_virtio_drv);
+}
+
+static void __exit p9_virtio_cleanup(void)
+{
+	unregister_virtio_driver(&p9_virtio_drv);
+	v9fs_unregister_trans(&p9_virtio_trans);
+}
+
+module_init(p9_virtio_init);
+module_exit(p9_virtio_cleanup);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_DESCRIPTION("Virtio 9p Transport");
+MODULE_LICENSE("GPL");

addons/9p/src/4.4.180/util.c

@@ -0,0 +1,141 @@
+/*
+ *  net/9p/util.c
+ *
+ *  This file contains some helper functions
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+
+/**
+ * struct p9_idpool - per-connection accounting for tag idpool
+ * @lock: protects the pool
+ * @pool: idr to allocate tag id from
+ *
+ */
+
+struct p9_idpool {
+	spinlock_t lock;
+	struct idr pool;
+};
+
+/**
+ * p9_idpool_create - create a new per-connection id pool
+ *
+ */
+
+struct p9_idpool *p9_idpool_create(void)
+{
+	struct p9_idpool *p;
+
+	p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL);
+	if (!p)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock_init(&p->lock);
+	idr_init(&p->pool);
+
+	return p;
+}
+EXPORT_SYMBOL(p9_idpool_create);
+
+/**
+ * p9_idpool_destroy - create a new per-connection id pool
+ * @p: idpool to destroy
+ */
+
+void p9_idpool_destroy(struct p9_idpool *p)
+{
+	idr_destroy(&p->pool);
+	kfree(p);
+}
+EXPORT_SYMBOL(p9_idpool_destroy);
+
+/**
+ * p9_idpool_get - allocate numeric id from pool
+ * @p: pool to allocate from
+ *
+ * Bugs: This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+int p9_idpool_get(struct p9_idpool *p)
+{
+	int i;
+	unsigned long flags;
+
+	idr_preload(GFP_NOFS);
+	spin_lock_irqsave(&p->lock, flags);
+
+	/* no need to store exactly p, we just need something non-null */
+	i = idr_alloc(&p->pool, p, 0, 0, GFP_NOWAIT);
+
+	spin_unlock_irqrestore(&p->lock, flags);
+	idr_preload_end();
+	if (i < 0)
+		return -1;
+
+	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", i, p);
+	return i;
+}
+EXPORT_SYMBOL(p9_idpool_get);
+
+/**
+ * p9_idpool_put - release numeric id from pool
+ * @id: numeric id which is being released
+ * @p: pool to release id into
+ *
+ * Bugs: This seems to be an awful generic function, should it be in idr.c with
+ *            the lock included in struct idr?
+ */
+
+void p9_idpool_put(int id, struct p9_idpool *p)
+{
+	unsigned long flags;
+
+	p9_debug(P9_DEBUG_MUX, " id %d pool %p\n", id, p);
+
+	spin_lock_irqsave(&p->lock, flags);
+	idr_remove(&p->pool, id);
+	spin_unlock_irqrestore(&p->lock, flags);
+}
+EXPORT_SYMBOL(p9_idpool_put);
+
+/**
+ * p9_idpool_check - check if the specified id is available
+ * @id: id to check
+ * @p: pool to check
+ */
+
+int p9_idpool_check(int id, struct p9_idpool *p)
+{
+	return idr_find(&p->pool, id) != NULL;
+}
+EXPORT_SYMBOL(p9_idpool_check);
+

addons/9p/src/4.4.180/v9fs.c

@@ -0,0 +1,700 @@
+/*
+ *  linux/fs/9p/v9fs.c
+ *
+ *  This file contains functions assisting in mapping VFS to 9P2000
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "cache.h"
+
+static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
+static LIST_HEAD(v9fs_sessionlist);
+struct kmem_cache *v9fs_inode_cache;
+
+/*
+ * Option Parsing (code inspired by NFS code)
+ *  NOTE: each transport will parse its own options
+ */
+
+enum {
+	/* Options that take integer arguments */
+	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
+	/* String options */
+	Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
+	/* Options that take no arguments */
+	Opt_nodevmap,
+	/* Cache options */
+	Opt_cache_loose, Opt_fscache, Opt_mmap,
+	/* Access options */
+	Opt_access, Opt_posixacl,
+	/* Lock timeout option */
+	Opt_locktimeout,
+	/* Error token */
+	Opt_err
+};
+
+static const match_table_t tokens = {
+	{Opt_debug, "debug=%x"},
+	{Opt_dfltuid, "dfltuid=%u"},
+	{Opt_dfltgid, "dfltgid=%u"},
+	{Opt_afid, "afid=%u"},
+	{Opt_uname, "uname=%s"},
+	{Opt_remotename, "aname=%s"},
+	{Opt_nodevmap, "nodevmap"},
+	{Opt_cache, "cache=%s"},
+	{Opt_cache_loose, "loose"},
+	{Opt_fscache, "fscache"},
+	{Opt_mmap, "mmap"},
+	{Opt_cachetag, "cachetag=%s"},
+	{Opt_access, "access=%s"},
+	{Opt_posixacl, "posixacl"},
+	{Opt_locktimeout, "locktimeout=%u"},
+	{Opt_err, NULL}
+};
+
+/* Interpret mount options for cache mode */
+static int get_cache_mode(char *s)
+{
+	int version = -EINVAL;
+
+	if (!strcmp(s, "loose")) {
+		version = CACHE_LOOSE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: loose\n");
+	} else if (!strcmp(s, "fscache")) {
+		version = CACHE_FSCACHE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n");
+	} else if (!strcmp(s, "mmap")) {
+		version = CACHE_MMAP;
+		p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n");
+	} else if (!strcmp(s, "none")) {
+		version = CACHE_NONE;
+		p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
+	} else
+		pr_info("Unknown Cache mode %s\n", s);
+	return version;
+}
+
+/**
+ * v9fs_parse_options - parse mount options into session structure
+ * @v9ses: existing v9fs session information
+ *
+ * Return 0 upon success, -ERRNO upon failure.
+ */
+
+static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
+{
+	char *options, *tmp_options;
+	substring_t args[MAX_OPT_ARGS];
+	char *p;
+	int option = 0;
+	char *s, *e;
+	int ret = 0;
+
+	/* setup defaults */
+	v9ses->afid = ~0;
+	v9ses->debug = 0;
+	v9ses->cache = CACHE_NONE;
+#ifdef CONFIG_9P_FSCACHE
+	v9ses->cachetag = NULL;
+#endif
+	v9ses->session_lock_timeout = P9_LOCK_TIMEOUT;
+
+	if (!opts)
+		return 0;
+
+	tmp_options = kstrdup(opts, GFP_KERNEL);
+	if (!tmp_options) {
+		ret = -ENOMEM;
+		goto fail_option_alloc;
+	}
+	options = tmp_options;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token, r;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_debug:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->debug = option;
+#ifdef CONFIG_NET_9P_DEBUG
+			p9_debug_level = option;
+#endif
+			break;
+
+		case Opt_dfltuid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->dfltuid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(v9ses->dfltuid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "uid field, but not a uid?\n");
+				ret = -EINVAL;
+				continue;
+			}
+			break;
+		case Opt_dfltgid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->dfltgid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(v9ses->dfltgid)) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "gid field, but not a gid?\n");
+				ret = -EINVAL;
+				continue;
+			}
+			break;
+		case Opt_afid:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			v9ses->afid = option;
+			break;
+		case Opt_uname:
+			kfree(v9ses->uname);
+			v9ses->uname = match_strdup(&args[0]);
+			if (!v9ses->uname) {
+				ret = -ENOMEM;
+				goto free_and_return;
+			}
+			break;
+		case Opt_remotename:
+			kfree(v9ses->aname);
+			v9ses->aname = match_strdup(&args[0]);
+			if (!v9ses->aname) {
+				ret = -ENOMEM;
+				goto free_and_return;
+			}
+			break;
+		case Opt_nodevmap:
+			v9ses->nodev = 1;
+			break;
+		case Opt_cache_loose:
+			v9ses->cache = CACHE_LOOSE;
+			break;
+		case Opt_fscache:
+			v9ses->cache = CACHE_FSCACHE;
+			break;
+		case Opt_mmap:
+			v9ses->cache = CACHE_MMAP;
+			break;
+		case Opt_cachetag:
+#ifdef CONFIG_9P_FSCACHE
+			v9ses->cachetag = match_strdup(&args[0]);
+#endif
+			break;
+		case Opt_cache:
+			s = match_strdup(&args[0]);
+			if (!s) {
+				ret = -ENOMEM;
+				p9_debug(P9_DEBUG_ERROR,
+					 "problem allocating copy of cache arg\n");
+				goto free_and_return;
+			}
+			ret = get_cache_mode(s);
+			if (ret == -EINVAL) {
+				kfree(s);
+				goto free_and_return;
+			}
+
+			v9ses->cache = ret;
+			kfree(s);
+			break;
+
+		case Opt_access:
+			s = match_strdup(&args[0]);
+			if (!s) {
+				ret = -ENOMEM;
+				p9_debug(P9_DEBUG_ERROR,
+					 "problem allocating copy of access arg\n");
+				goto free_and_return;
+			}
+
+			v9ses->flags &= ~V9FS_ACCESS_MASK;
+			if (strcmp(s, "user") == 0)
+				v9ses->flags |= V9FS_ACCESS_USER;
+			else if (strcmp(s, "any") == 0)
+				v9ses->flags |= V9FS_ACCESS_ANY;
+			else if (strcmp(s, "client") == 0) {
+				v9ses->flags |= V9FS_ACCESS_CLIENT;
+			} else {
+				uid_t uid;
+				v9ses->flags |= V9FS_ACCESS_SINGLE;
+				uid = simple_strtoul(s, &e, 10);
+				if (*e != '\0') {
+					ret = -EINVAL;
+					pr_info("Unknown access argument %s\n",
+						s);
+					kfree(s);
+					goto free_and_return;
+				}
+				v9ses->uid = make_kuid(current_user_ns(), uid);
+				if (!uid_valid(v9ses->uid)) {
+					ret = -EINVAL;
+					pr_info("Uknown uid %s\n", s);
+					kfree(s);
+					goto free_and_return;
+				}
+			}
+
+			kfree(s);
+			break;
+
+		case Opt_posixacl:
+#ifdef CONFIG_9P_FS_POSIX_ACL
+			v9ses->flags |= V9FS_POSIX_ACL;
+#else
+			p9_debug(P9_DEBUG_ERROR,
+				 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
+#endif
+			break;
+
+		case Opt_locktimeout:
+			r = match_int(&args[0], &option);
+			if (r < 0) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+			if (option < 1) {
+				p9_debug(P9_DEBUG_ERROR,
+					 "locktimeout must be a greater than zero integer.\n");
+				ret = -EINVAL;
+				continue;
+			}
+			v9ses->session_lock_timeout = (long)option * HZ;
+			break;
+
+		default:
+			continue;
+		}
+	}
+
+free_and_return:
+	kfree(tmp_options);
+fail_option_alloc:
+	return ret;
+}
+
+/**
+ * v9fs_session_init - initialize session
+ * @v9ses: session information structure
+ * @dev_name: device being mounted
+ * @data: options
+ *
+ */
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
+		  const char *dev_name, char *data)
+{
+	struct p9_fid *fid;
+	int rc = -ENOMEM;
+
+	v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
+	if (!v9ses->uname)
+		goto err_names;
+
+	v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
+	if (!v9ses->aname)
+		goto err_names;
+	init_rwsem(&v9ses->rename_sem);
+
+	rc = bdi_setup_and_register(&v9ses->bdi, "9p");
+	if (rc)
+		goto err_names;
+
+	v9ses->uid = INVALID_UID;
+	v9ses->dfltuid = V9FS_DEFUID;
+	v9ses->dfltgid = V9FS_DEFGID;
+
+	v9ses->clnt = p9_client_create(dev_name, data);
+	if (IS_ERR(v9ses->clnt)) {
+		rc = PTR_ERR(v9ses->clnt);
+		p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n");
+		goto err_bdi;
+	}
+
+	v9ses->flags = V9FS_ACCESS_USER;
+
+	if (p9_is_proto_dotl(v9ses->clnt)) {
+		v9ses->flags = V9FS_ACCESS_CLIENT;
+		v9ses->flags |= V9FS_PROTO_2000L;
+	} else if (p9_is_proto_dotu(v9ses->clnt)) {
+		v9ses->flags |= V9FS_PROTO_2000U;
+	}
+
+	rc = v9fs_parse_options(v9ses, data);
+	if (rc < 0)
+		goto err_clnt;
+
+	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
+
+	if (!v9fs_proto_dotl(v9ses) &&
+	    ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
+		/*
+		 * We support ACCESS_CLIENT only for dotl.
+		 * Fall back to ACCESS_USER
+		 */
+		v9ses->flags &= ~V9FS_ACCESS_MASK;
+		v9ses->flags |= V9FS_ACCESS_USER;
+	}
+	/*FIXME !! */
+	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
+	if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) &&
+		((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
+
+		v9ses->flags &= ~V9FS_ACCESS_MASK;
+		v9ses->flags |= V9FS_ACCESS_ANY;
+		v9ses->uid = INVALID_UID;
+	}
+	if (!v9fs_proto_dotl(v9ses) ||
+		!((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
+		/*
+		 * We support ACL checks on clinet only if the protocol is
+		 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
+		 */
+		v9ses->flags &= ~V9FS_ACL_MASK;
+	}
+
+	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
+							v9ses->aname);
+	if (IS_ERR(fid)) {
+		rc = PTR_ERR(fid);
+		p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
+		goto err_clnt;
+	}
+
+	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
+		fid->uid = v9ses->uid;
+	else
+		fid->uid = INVALID_UID;
+
+#ifdef CONFIG_9P_FSCACHE
+	/* register the session for caching */
+	v9fs_cache_session_get_cookie(v9ses);
+#endif
+	spin_lock(&v9fs_sessionlist_lock);
+	list_add(&v9ses->slist, &v9fs_sessionlist);
+	spin_unlock(&v9fs_sessionlist_lock);
+
+	return fid;
+
+err_clnt:
+	p9_client_destroy(v9ses->clnt);
+err_bdi:
+	bdi_destroy(&v9ses->bdi);
+err_names:
+	kfree(v9ses->uname);
+	kfree(v9ses->aname);
+	return ERR_PTR(rc);
+}
+
+/**
+ * v9fs_session_close - shutdown a session
+ * @v9ses: session information structure
+ *
+ */
+
+void v9fs_session_close(struct v9fs_session_info *v9ses)
+{
+	if (v9ses->clnt) {
+		p9_client_destroy(v9ses->clnt);
+		v9ses->clnt = NULL;
+	}
+
+#ifdef CONFIG_9P_FSCACHE
+	if (v9ses->fscache) {
+		v9fs_cache_session_put_cookie(v9ses);
+		kfree(v9ses->cachetag);
+	}
+#endif
+	kfree(v9ses->uname);
+	kfree(v9ses->aname);
+
+	bdi_destroy(&v9ses->bdi);
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_del(&v9ses->slist);
+	spin_unlock(&v9fs_sessionlist_lock);
+}
+
+/**
+ * v9fs_session_cancel - terminate a session
+ * @v9ses: session to terminate
+ *
+ * mark transport as disconnected and cancel all pending requests.
+ */
+
+void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
+	p9_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
+	p9_client_disconnect(v9ses->clnt);
+}
+
+/**
+ * v9fs_session_begin_cancel - Begin terminate of a session
+ * @v9ses: session to terminate
+ *
+ * After this call we don't allow any request other than clunk.
+ */
+
+void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
+{
+	p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
+	p9_client_begin_disconnect(v9ses->clnt);
+}
+
+extern int v9fs_error_init(void);
+
+static struct kobject *v9fs_kobj;
+
+#ifdef CONFIG_9P_FSCACHE
+/**
+ * caches_show - list caches associated with a session
+ *
+ * Returns the size of buffer written.
+ */
+
+static ssize_t caches_show(struct kobject *kobj,
+			   struct kobj_attribute *attr,
+			   char *buf)
+{
+	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
+	struct v9fs_session_info *v9ses;
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
+		if (v9ses->cachetag) {
+			n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
+			if (n < 0) {
+				count = n;
+				break;
+			}
+
+			count += n;
+			limit -= n;
+		}
+	}
+
+	spin_unlock(&v9fs_sessionlist_lock);
+	return count;
+}
+
+static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
+#endif /* CONFIG_9P_FSCACHE */
+
+static struct attribute *v9fs_attrs[] = {
+#ifdef CONFIG_9P_FSCACHE
+	&v9fs_attr_cache.attr,
+#endif
+	NULL,
+};
+
+static struct attribute_group v9fs_attr_group = {
+	.attrs = v9fs_attrs,
+};
+
+/**
+ * v9fs_sysfs_init - Initialize the v9fs sysfs interface
+ *
+ */
+
+static int __init v9fs_sysfs_init(void)
+{
+	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
+	if (!v9fs_kobj)
+		return -ENOMEM;
+
+	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
+		kobject_put(v9fs_kobj);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
+ *
+ */
+
+static void v9fs_sysfs_cleanup(void)
+{
+	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
+	kobject_put(v9fs_kobj);
+}
+
+static void v9fs_inode_init_once(void *foo)
+{
+	struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
+#ifdef CONFIG_9P_FSCACHE
+	v9inode->fscache = NULL;
+#endif
+	memset(&v9inode->qid, 0, sizeof(v9inode->qid));
+	inode_init_once(&v9inode->vfs_inode);
+}
+
+/**
+ * v9fs_init_inode_cache - initialize a cache for 9P
+ * Returns 0 on success.
+ */
+static int v9fs_init_inode_cache(void)
+{
+	v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache",
+					  sizeof(struct v9fs_inode),
+					  0, (SLAB_RECLAIM_ACCOUNT|
+					      SLAB_MEM_SPREAD),
+					  v9fs_inode_init_once);
+	if (!v9fs_inode_cache)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/**
+ * v9fs_destroy_inode_cache - destroy the cache of 9P inode
+ *
+ */
+static void v9fs_destroy_inode_cache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(v9fs_inode_cache);
+}
+
+static int v9fs_cache_register(void)
+{
+	int ret;
+	ret = v9fs_init_inode_cache();
+	if (ret < 0)
+		return ret;
+#ifdef CONFIG_9P_FSCACHE
+	ret = fscache_register_netfs(&v9fs_cache_netfs);
+	if (ret < 0)
+		v9fs_destroy_inode_cache();
+#endif
+	return ret;
+}
+
+static void v9fs_cache_unregister(void)
+{
+	v9fs_destroy_inode_cache();
+#ifdef CONFIG_9P_FSCACHE
+	fscache_unregister_netfs(&v9fs_cache_netfs);
+#endif
+}
+
+/**
+ * init_v9fs - Initialize module
+ *
+ */
+
+static int __init init_v9fs(void)
+{
+	int err;
+	pr_info("Installing v9fs 9p2000 file system support\n");
+	/* TODO: Setup list of registered trasnport modules */
+
+	err = v9fs_cache_register();
+	if (err < 0) {
+		pr_err("Failed to register v9fs for caching\n");
+		return err;
+	}
+
+	err = v9fs_sysfs_init();
+	if (err < 0) {
+		pr_err("Failed to register with sysfs\n");
+		goto out_cache;
+	}
+	err = register_filesystem(&v9fs_fs_type);
+	if (err < 0) {
+		pr_err("Failed to register filesystem\n");
+		goto out_sysfs_cleanup;
+	}
+
+	return 0;
+
+out_sysfs_cleanup:
+	v9fs_sysfs_cleanup();
+
+out_cache:
+	v9fs_cache_unregister();
+
+	return err;
+}
+
+/**
+ * exit_v9fs - shutdown module
+ *
+ */
+
+static void __exit exit_v9fs(void)
+{
+	v9fs_sysfs_cleanup();
+	v9fs_cache_unregister();
+	unregister_filesystem(&v9fs_fs_type);
+}
+
+module_init(init_v9fs)
+module_exit(exit_v9fs)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");

addons/9p/src/4.4.180/v9fs.h

@@ -0,0 +1,226 @@
+/*
+ * V9FS definitions.
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_V9FS_H
+#define FS_9P_V9FS_H
+
+#include <linux/backing-dev.h>
+
+/**
+ * enum p9_session_flags - option flags for each 9P session
+ * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
+ * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
+ * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
+ * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
+ * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
+ * @V9FS_ACCESS_ANY: use a single attach for all users
+ * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
+ * @V9FS_POSIX_ACL: POSIX ACLs are enforced
+ *
+ * Session flags reflect options selected by users at mount time
+ */
+#define	V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
+			 V9FS_ACCESS_USER |   \
+			 V9FS_ACCESS_CLIENT)
+#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
+#define V9FS_ACL_MASK V9FS_POSIX_ACL
+
+enum p9_session_flags {
+	V9FS_PROTO_2000U	= 0x01,
+	V9FS_PROTO_2000L	= 0x02,
+	V9FS_ACCESS_SINGLE	= 0x04,
+	V9FS_ACCESS_USER	= 0x08,
+	V9FS_ACCESS_CLIENT	= 0x10,
+	V9FS_POSIX_ACL		= 0x20
+};
+
+/* possible values of ->cache */
+/**
+ * enum p9_cache_modes - user specified cache preferences
+ * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
+ * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
+ *
+ * eventually support loose, tight, time, session, default always none
+ */
+
+enum p9_cache_modes {
+	CACHE_NONE,
+	CACHE_MMAP,
+	CACHE_LOOSE,
+	CACHE_FSCACHE,
+};
+
+/**
+ * struct v9fs_session_info - per-instance session information
+ * @flags: session options of type &p9_session_flags
+ * @nodev: set to 1 to disable device mapping
+ * @debug: debug level
+ * @afid: authentication handle
+ * @cache: cache mode of type &p9_cache_modes
+ * @cachetag: the tag of the cache associated with this session
+ * @fscache: session cookie associated with FS-Cache
+ * @uname: string user name to mount hierarchy as
+ * @aname: mount specifier for remote hierarchy
+ * @maxdata: maximum data to be sent/recvd per protocol message
+ * @dfltuid: default numeric userid to mount hierarchy as
+ * @dfltgid: default numeric groupid to mount hierarchy as
+ * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
+ * @clnt: reference to 9P network client instantiated for this session
+ * @slist: reference to list of registered 9p sessions
+ *
+ * This structure holds state for each session instance established during
+ * a sys_mount() .
+ *
+ * Bugs: there seems to be a lot of state which could be condensed and/or
+ * removed.
+ */
+
+struct v9fs_session_info {
+	/* options */
+	unsigned char flags;
+	unsigned char nodev;
+	unsigned short debug;
+	unsigned int afid;
+	unsigned int cache;
+#ifdef CONFIG_9P_FSCACHE
+	char *cachetag;
+	struct fscache_cookie *fscache;
+#endif
+
+	char *uname;		/* user name to mount as */
+	char *aname;		/* name of remote hierarchy being mounted */
+	unsigned int maxdata;	/* max data for client interface */
+	kuid_t dfltuid;		/* default uid/muid for legacy support */
+	kgid_t dfltgid;		/* default gid for legacy support */
+	kuid_t uid;		/* if ACCESS_SINGLE, the uid that has access */
+	struct p9_client *clnt;	/* 9p client */
+	struct list_head slist; /* list of sessions registered with v9fs */
+	struct backing_dev_info bdi;
+	struct rw_semaphore rename_sem;
+	long session_lock_timeout; /* retry interval for blocking locks */
+};
+
+/* cache_validity flags */
+#define V9FS_INO_INVALID_ATTR 0x01
+
+struct v9fs_inode {
+#ifdef CONFIG_9P_FSCACHE
+	struct mutex fscache_lock;
+	struct fscache_cookie *fscache;
+#endif
+	struct p9_qid qid;
+	unsigned int cache_validity;
+	struct p9_fid *writeback_fid;
+	struct mutex v_mutex;
+	struct inode vfs_inode;
+};
+
+static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
+{
+	return container_of(inode, struct v9fs_inode, vfs_inode);
+}
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
+									char *);
+extern void v9fs_session_close(struct v9fs_session_info *v9ses);
+extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
+extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
+extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
+			unsigned int flags);
+extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
+extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry);
+extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
+					 struct p9_fid *fid,
+					 struct super_block *sb, int new);
+extern const struct inode_operations v9fs_dir_inode_operations_dotl;
+extern const struct inode_operations v9fs_file_inode_operations_dotl;
+extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
+extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
+					      struct p9_fid *fid,
+					      struct super_block *sb, int new);
+
+/* other default globals */
+#define V9FS_PORT	564
+#define V9FS_DEFUSER	"nobody"
+#define V9FS_DEFANAME	""
+#define V9FS_DEFUID	KUIDT_INIT(-2)
+#define V9FS_DEFGID	KGIDT_INIT(-2)
+
+static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
+{
+	return (inode->i_sb->s_fs_info);
+}
+
+static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
+{
+	return dentry->d_sb->s_fs_info;
+}
+
+static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_PROTO_2000U;
+}
+
+static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_PROTO_2000L;
+}
+
+/**
+ * v9fs_get_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+			struct super_block *sb)
+{
+	if (v9fs_proto_dotl(v9ses))
+		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
+	else
+		return v9fs_inode_from_fid(v9ses, fid, sb, 0);
+}
+
+/**
+ * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
+ * issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+static inline struct inode *
+v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+			    struct super_block *sb)
+{
+	if (v9fs_proto_dotl(v9ses))
+		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
+	else
+		return v9fs_inode_from_fid(v9ses, fid, sb, 1);
+}
+
+#endif

addons/9p/src/4.4.180/v9fs_vfs.h

@@ -0,0 +1,105 @@
+/*
+ * V9FS VFS extensions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+#ifndef FS_9P_V9FS_VFS_H
+#define FS_9P_V9FS_VFS_H
+
+/* plan9 semantics are that created files are implicitly opened.
+ * But linux semantics are that you call create, then open.
+ * the plan9 approach is superior as it provides an atomic
+ * open.
+ * we track the create fid here. When the file is opened, if fidopen is
+ * non-zero, we use the fid and can skip some steps.
+ * there may be a better way to do this, but I don't know it.
+ * one BAD way is to clunk the fid on create, then open it again:
+ * you lose the atomicity of file open
+ */
+
+/* special case:
+ * unlink calls remove, which is an implicit clunk. So we have to track
+ * that kind of thing so that we don't try to clunk a dead fid.
+ */
+#define P9_LOCK_TIMEOUT (30*HZ)
+
+/* flags for v9fs_stat2inode() & v9fs_stat2inode_dotl() */
+#define V9FS_STAT2INODE_KEEP_ISIZE 1
+
+extern struct file_system_type v9fs_fs_type;
+extern const struct address_space_operations v9fs_addr_operations;
+extern const struct file_operations v9fs_file_operations;
+extern const struct file_operations v9fs_file_operations_dotl;
+extern const struct file_operations v9fs_dir_operations;
+extern const struct file_operations v9fs_dir_operations_dotl;
+extern const struct dentry_operations v9fs_dentry_operations;
+extern const struct dentry_operations v9fs_cached_dentry_operations;
+extern const struct file_operations v9fs_cached_file_operations;
+extern const struct file_operations v9fs_cached_file_operations_dotl;
+extern const struct file_operations v9fs_mmap_file_operations;
+extern const struct file_operations v9fs_mmap_file_operations_dotl;
+extern struct kmem_cache *v9fs_inode_cache;
+
+struct inode *v9fs_alloc_inode(struct super_block *sb);
+void v9fs_destroy_inode(struct inode *inode);
+struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t);
+int v9fs_init_inode(struct v9fs_session_info *v9ses,
+		    struct inode *inode, umode_t mode, dev_t);
+void v9fs_evict_inode(struct inode *inode);
+ino_t v9fs_qid2ino(struct p9_qid *qid);
+void v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
+		      struct super_block *sb, unsigned int flags);
+void v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
+			   unsigned int flags);
+int v9fs_dir_release(struct inode *inode, struct file *filp);
+int v9fs_file_open(struct inode *inode, struct file *file);
+void v9fs_inode2stat(struct inode *inode, struct p9_wstat *stat);
+int v9fs_uflags2omode(int uflags, int extended);
+
+void v9fs_blank_wstat(struct p9_wstat *wstat);
+int v9fs_vfs_setattr_dotl(struct dentry *, struct iattr *);
+int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
+			 int datasync);
+int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode);
+int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode);
+static inline void v9fs_invalidate_inode_attr(struct inode *inode)
+{
+	struct v9fs_inode *v9inode;
+	v9inode = V9FS_I(inode);
+	v9inode->cache_validity |= V9FS_INO_INVALID_ATTR;
+	return;
+}
+
+int v9fs_open_to_dotl_flags(int flags);
+
+static inline void v9fs_i_size_write(struct inode *inode, loff_t i_size)
+{
+	/*
+	 * 32-bit need the lock, concurrent updates could break the
+	 * sequences and make i_size_read() loop forever.
+	 * 64-bit updates are atomic and can skip the locking.
+	 */
+	if (sizeof(i_size) > sizeof(long))
+		spin_lock(&inode->i_lock);
+	i_size_write(inode, i_size);
+	if (sizeof(i_size) > sizeof(long))
+		spin_unlock(&inode->i_lock);
+}
+#endif

addons/9p/src/4.4.180/vfs_addr.c

@@ -0,0 +1,351 @@
+/*
+ *  linux/fs/9p/vfs_addr.c
+ *
+ * This file contians vfs address (mmap) ops for 9P2000.
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "cache.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_readpage - read an entire page in from 9P
+ *
+ * @fid: fid being read
+ * @page: structure to page
+ *
+ */
+static int v9fs_fid_readpage(struct p9_fid *fid, struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	struct bio_vec bvec = {.bv_page = page, .bv_len = PAGE_SIZE};
+	struct iov_iter to;
+	int retval, err;
+
+	p9_debug(P9_DEBUG_VFS, "\n");
+
+	BUG_ON(!PageLocked(page));
+
+	retval = v9fs_readpage_from_fscache(inode, page);
+	if (retval == 0)
+		return retval;
+
+	iov_iter_bvec(&to, ITER_BVEC | READ, &bvec, 1, PAGE_SIZE);
+
+	retval = p9_client_read(fid, page_offset(page), &to, &err);
+	if (err) {
+		v9fs_uncache_page(inode, page);
+		retval = err;
+		goto done;
+	}
+
+	zero_user(page, retval, PAGE_SIZE - retval);
+	flush_dcache_page(page);
+	SetPageUptodate(page);
+
+	v9fs_readpage_to_fscache(inode, page);
+	retval = 0;
+
+done:
+	unlock_page(page);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_readpage - read an entire page in from 9P
+ *
+ * @filp: file being read
+ * @page: structure to page
+ *
+ */
+
+static int v9fs_vfs_readpage(struct file *filp, struct page *page)
+{
+	return v9fs_fid_readpage(filp->private_data, page);
+}
+
+/**
+ * v9fs_vfs_readpages - read a set of pages from 9P
+ *
+ * @filp: file being read
+ * @mapping: the address space
+ * @pages: list of pages to read
+ * @nr_pages: count of pages to read
+ *
+ */
+
+static int v9fs_vfs_readpages(struct file *filp, struct address_space *mapping,
+			     struct list_head *pages, unsigned nr_pages)
+{
+	int ret = 0;
+	struct inode *inode;
+
+	inode = mapping->host;
+	p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, filp);
+
+	ret = v9fs_readpages_from_fscache(inode, mapping, pages, &nr_pages);
+	if (ret == 0)
+		return ret;
+
+	ret = read_cache_pages(mapping, pages, (void *)v9fs_vfs_readpage, filp);
+	p9_debug(P9_DEBUG_VFS, "  = %d\n", ret);
+	return ret;
+}
+
+/**
+ * v9fs_release_page - release the private state associated with a page
+ *
+ * Returns 1 if the page can be released, false otherwise.
+ */
+
+static int v9fs_release_page(struct page *page, gfp_t gfp)
+{
+	if (PagePrivate(page))
+		return 0;
+	return v9fs_fscache_release_page(page, gfp);
+}
+
+/**
+ * v9fs_invalidate_page - Invalidate a page completely or partially
+ *
+ * @page: structure to page
+ * @offset: offset in the page
+ */
+
+static void v9fs_invalidate_page(struct page *page, unsigned int offset,
+				 unsigned int length)
+{
+	/*
+	 * If called with zero offset, we should release
+	 * the private state assocated with the page
+	 */
+	if (offset == 0 && length == PAGE_CACHE_SIZE)
+		v9fs_fscache_invalidate_page(page);
+}
+
+static int v9fs_vfs_writepage_locked(struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	loff_t size = i_size_read(inode);
+	struct iov_iter from;
+	struct bio_vec bvec;
+	int err, len;
+
+	if (page->index == size >> PAGE_CACHE_SHIFT)
+		len = size & ~PAGE_CACHE_MASK;
+	else
+		len = PAGE_CACHE_SIZE;
+
+	bvec.bv_page = page;
+	bvec.bv_offset = 0;
+	bvec.bv_len = len;
+	iov_iter_bvec(&from, ITER_BVEC | WRITE, &bvec, 1, len);
+
+	/* We should have writeback_fid always set */
+	BUG_ON(!v9inode->writeback_fid);
+
+	set_page_writeback(page);
+
+	p9_client_write(v9inode->writeback_fid, page_offset(page), &from, &err);
+
+	end_page_writeback(page);
+	return err;
+}
+
+static int v9fs_vfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	int retval;
+
+	p9_debug(P9_DEBUG_VFS, "page %p\n", page);
+
+	retval = v9fs_vfs_writepage_locked(page);
+	if (retval < 0) {
+		if (retval == -EAGAIN) {
+			redirty_page_for_writepage(wbc, page);
+			retval = 0;
+		} else {
+			SetPageError(page);
+			mapping_set_error(page->mapping, retval);
+		}
+	} else
+		retval = 0;
+
+	unlock_page(page);
+	return retval;
+}
+
+/**
+ * v9fs_launder_page - Writeback a dirty page
+ * Returns 0 on success.
+ */
+
+static int v9fs_launder_page(struct page *page)
+{
+	int retval;
+	struct inode *inode = page->mapping->host;
+
+	v9fs_fscache_wait_on_page_write(inode, page);
+	if (clear_page_dirty_for_io(page)) {
+		retval = v9fs_vfs_writepage_locked(page);
+		if (retval)
+			return retval;
+	}
+	return 0;
+}
+
+/**
+ * v9fs_direct_IO - 9P address space operation for direct I/O
+ * @iocb: target I/O control block
+ * @pos: offset in file to begin the operation
+ *
+ * The presence of v9fs_direct_IO() in the address space ops vector
+ * allowes open() O_DIRECT flags which would have failed otherwise.
+ *
+ * In the non-cached mode, we shunt off direct read and write requests before
+ * the VFS gets them, so this method should never be called.
+ *
+ * Direct IO is not 'yet' supported in the cached mode. Hence when
+ * this routine is called through generic_file_aio_read(), the read/write fails
+ * with an error.
+ *
+ */
+static ssize_t
+v9fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t pos)
+{
+	struct file *file = iocb->ki_filp;
+	ssize_t n;
+	int err = 0;
+	if (iov_iter_rw(iter) == WRITE) {
+		n = p9_client_write(file->private_data, pos, iter, &err);
+		if (n) {
+			struct inode *inode = file_inode(file);
+			loff_t i_size = i_size_read(inode);
+			if (pos + n > i_size)
+				inode_add_bytes(inode, pos + n - i_size);
+		}
+	} else {
+		n = p9_client_read(file->private_data, pos, iter, &err);
+	}
+	return n ? n : err;
+}
+
+static int v9fs_write_begin(struct file *filp, struct address_space *mapping,
+			    loff_t pos, unsigned len, unsigned flags,
+			    struct page **pagep, void **fsdata)
+{
+	int retval = 0;
+	struct page *page;
+	struct v9fs_inode *v9inode;
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+	struct inode *inode = mapping->host;
+
+
+	p9_debug(P9_DEBUG_VFS, "filp %p, mapping %p\n", filp, mapping);
+
+	v9inode = V9FS_I(inode);
+start:
+	page = grab_cache_page_write_begin(mapping, index, flags);
+	if (!page) {
+		retval = -ENOMEM;
+		goto out;
+	}
+	BUG_ON(!v9inode->writeback_fid);
+	if (PageUptodate(page))
+		goto out;
+
+	if (len == PAGE_CACHE_SIZE)
+		goto out;
+
+	retval = v9fs_fid_readpage(v9inode->writeback_fid, page);
+	page_cache_release(page);
+	if (!retval)
+		goto start;
+out:
+	*pagep = page;
+	return retval;
+}
+
+static int v9fs_write_end(struct file *filp, struct address_space *mapping,
+			  loff_t pos, unsigned len, unsigned copied,
+			  struct page *page, void *fsdata)
+{
+	loff_t last_pos = pos + copied;
+	struct inode *inode = page->mapping->host;
+
+	p9_debug(P9_DEBUG_VFS, "filp %p, mapping %p\n", filp, mapping);
+
+	if (unlikely(copied < len)) {
+		/*
+		 * zero out the rest of the area
+		 */
+		unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+
+		zero_user(page, from + copied, len - copied);
+		flush_dcache_page(page);
+	}
+
+	if (!PageUptodate(page))
+		SetPageUptodate(page);
+	/*
+	 * No need to use i_size_read() here, the i_size
+	 * cannot change under us because we hold the i_mutex.
+	 */
+	if (last_pos > inode->i_size) {
+		inode_add_bytes(inode, last_pos - inode->i_size);
+		i_size_write(inode, last_pos);
+	}
+	set_page_dirty(page);
+	unlock_page(page);
+	page_cache_release(page);
+
+	return copied;
+}
+
+
+const struct address_space_operations v9fs_addr_operations = {
+	.readpage = v9fs_vfs_readpage,
+	.readpages = v9fs_vfs_readpages,
+	.set_page_dirty = __set_page_dirty_nobuffers,
+	.writepage = v9fs_vfs_writepage,
+	.write_begin = v9fs_write_begin,
+	.write_end = v9fs_write_end,
+	.releasepage = v9fs_release_page,
+	.invalidatepage = v9fs_invalidate_page,
+	.launder_page = v9fs_launder_page,
+	.direct_IO = v9fs_direct_IO,
+};

addons/9p/src/4.4.180/vfs_dentry.c

@@ -0,0 +1,122 @@
+/*
+ *  linux/fs/9p/vfs_dentry.c
+ *
+ * This file contians vfs dentry ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_cached_dentry_delete - called when dentry refcount equals 0
+ * @dentry:  dentry in question
+ *
+ */
+static int v9fs_cached_dentry_delete(const struct dentry *dentry)
+{
+	p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
+		 dentry, dentry);
+
+	/* Don't cache negative dentries */
+	if (d_really_is_negative(dentry))
+		return 1;
+	return 0;
+}
+
+/**
+ * v9fs_dentry_release - called when dentry is going to be freed
+ * @dentry:  dentry that is being release
+ *
+ */
+
+static void v9fs_dentry_release(struct dentry *dentry)
+{
+	struct hlist_node *p, *n;
+	p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
+		 dentry, dentry);
+	hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
+		p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
+	dentry->d_fsdata = NULL;
+}
+
+static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	struct p9_fid *fid;
+	struct inode *inode;
+	struct v9fs_inode *v9inode;
+
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	inode = d_inode(dentry);
+	if (!inode)
+		goto out_valid;
+
+	v9inode = V9FS_I(inode);
+	if (v9inode->cache_validity & V9FS_INO_INVALID_ATTR) {
+		int retval;
+		struct v9fs_session_info *v9ses;
+		fid = v9fs_fid_lookup(dentry);
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		v9ses = v9fs_inode2v9ses(inode);
+		if (v9fs_proto_dotl(v9ses))
+			retval = v9fs_refresh_inode_dotl(fid, inode);
+		else
+			retval = v9fs_refresh_inode(fid, inode);
+		if (retval == -ENOENT)
+			return 0;
+		if (retval < 0)
+			return retval;
+	}
+out_valid:
+	return 1;
+}
+
+const struct dentry_operations v9fs_cached_dentry_operations = {
+	.d_revalidate = v9fs_lookup_revalidate,
+	.d_weak_revalidate = v9fs_lookup_revalidate,
+	.d_delete = v9fs_cached_dentry_delete,
+	.d_release = v9fs_dentry_release,
+};
+
+const struct dentry_operations v9fs_dentry_operations = {
+	.d_delete = always_delete_dentry,
+	.d_release = v9fs_dentry_release,
+};

addons/9p/src/4.4.180/vfs_dir.c

@@ -0,0 +1,248 @@
+/*
+ * linux/fs/9p/vfs_dir.c
+ *
+ * This file contains vfs directory ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <linux/slab.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * struct p9_rdir - readdir accounting
+ * @head: start offset of current dirread buffer
+ * @tail: end offset of current dirread buffer
+ * @buf: dirread buffer
+ *
+ * private structure for keeping track of readdir
+ * allocated on demand
+ */
+
+struct p9_rdir {
+	int head;
+	int tail;
+	uint8_t buf[];
+};
+
+/**
+ * dt_type - return file type
+ * @mistat: mistat structure
+ *
+ */
+
+static inline int dt_type(struct p9_wstat *mistat)
+{
+	unsigned long perm = mistat->mode;
+	int rettype = DT_REG;
+
+	if (perm & P9_DMDIR)
+		rettype = DT_DIR;
+	if (perm & P9_DMSYMLINK)
+		rettype = DT_LNK;
+
+	return rettype;
+}
+
+/**
+ * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
+ * @filp: opened file structure
+ * @buflen: Length in bytes of buffer to allocate
+ *
+ */
+
+static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
+{
+	struct p9_fid *fid = filp->private_data;
+	if (!fid->rdir)
+		fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
+	return fid->rdir;
+}
+
+/**
+ * v9fs_dir_readdir - iterate through a directory
+ * @file: opened file structure
+ * @ctx: actor we feed the entries to
+ *
+ */
+
+static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
+{
+	bool over;
+	struct p9_wstat st;
+	int err = 0;
+	struct p9_fid *fid;
+	int buflen;
+	struct p9_rdir *rdir;
+	struct kvec kvec;
+
+	p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
+	fid = file->private_data;
+
+	buflen = fid->clnt->msize - P9_IOHDRSZ;
+
+	rdir = v9fs_alloc_rdir_buf(file, buflen);
+	if (!rdir)
+		return -ENOMEM;
+	kvec.iov_base = rdir->buf;
+	kvec.iov_len = buflen;
+
+	while (1) {
+		if (rdir->tail == rdir->head) {
+			struct iov_iter to;
+			int n;
+			iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buflen);
+			n = p9_client_read(file->private_data, ctx->pos, &to,
+					   &err);
+			if (err)
+				return err;
+			if (n == 0)
+				return 0;
+
+			rdir->head = 0;
+			rdir->tail = n;
+		}
+		while (rdir->head < rdir->tail) {
+			err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
+					  rdir->tail - rdir->head, &st);
+			if (err <= 0) {
+				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
+				return -EIO;
+			}
+
+			over = !dir_emit(ctx, st.name, strlen(st.name),
+					 v9fs_qid2ino(&st.qid), dt_type(&st));
+			p9stat_free(&st);
+			if (over)
+				return 0;
+
+			rdir->head += err;
+			ctx->pos += err;
+		}
+	}
+}
+
+/**
+ * v9fs_dir_readdir_dotl - iterate through a directory
+ * @file: opened file structure
+ * @ctx: actor we feed the entries to
+ *
+ */
+static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
+{
+	int err = 0;
+	struct p9_fid *fid;
+	int buflen;
+	struct p9_rdir *rdir;
+	struct p9_dirent curdirent;
+
+	p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
+	fid = file->private_data;
+
+	buflen = fid->clnt->msize - P9_READDIRHDRSZ;
+
+	rdir = v9fs_alloc_rdir_buf(file, buflen);
+	if (!rdir)
+		return -ENOMEM;
+
+	while (1) {
+		if (rdir->tail == rdir->head) {
+			err = p9_client_readdir(fid, rdir->buf, buflen,
+						ctx->pos);
+			if (err <= 0)
+				return err;
+
+			rdir->head = 0;
+			rdir->tail = err;
+		}
+
+		while (rdir->head < rdir->tail) {
+
+			err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
+					    rdir->tail - rdir->head,
+					    &curdirent);
+			if (err < 0) {
+				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
+				return -EIO;
+			}
+
+			if (!dir_emit(ctx, curdirent.d_name,
+				      strlen(curdirent.d_name),
+				      v9fs_qid2ino(&curdirent.qid),
+				      curdirent.d_type))
+				return 0;
+
+			ctx->pos = curdirent.d_off;
+			rdir->head += err;
+		}
+	}
+}
+
+
+/**
+ * v9fs_dir_release - close a directory
+ * @inode: inode of the directory
+ * @filp: file pointer to a directory
+ *
+ */
+
+int v9fs_dir_release(struct inode *inode, struct file *filp)
+{
+	struct p9_fid *fid;
+
+	fid = filp->private_data;
+	p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
+		 inode, filp, fid ? fid->fid : -1);
+	if (fid)
+		p9_client_clunk(fid);
+	return 0;
+}
+
+const struct file_operations v9fs_dir_operations = {
+	.read = generic_read_dir,
+	.llseek = generic_file_llseek,
+	.iterate = v9fs_dir_readdir,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+};
+
+const struct file_operations v9fs_dir_operations_dotl = {
+	.read = generic_read_dir,
+	.llseek = generic_file_llseek,
+	.iterate = v9fs_dir_readdir_dotl,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+        .fsync = v9fs_file_fsync_dotl,
+};

addons/9p/src/4.4.180/vfs_file.c

@@ -0,0 +1,726 @@
+/*
+ *  linux/fs/9p/vfs_file.c
+ *
+ * This file contians vfs file ops for 9P2000.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/list.h>
+#include <linux/pagemap.h>
+#include <linux/utsname.h>
+#include <asm/uaccess.h>
+#include <linux/idr.h>
+#include <linux/uio.h>
+#include <linux/slab.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+#include "cache.h"
+
+static const struct vm_operations_struct v9fs_file_vm_ops;
+static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
+
+/**
+ * v9fs_file_open - open a file (or directory)
+ * @inode: inode to be opened
+ * @file: file being opened
+ *
+ */
+
+int v9fs_file_open(struct inode *inode, struct file *file)
+{
+	int err;
+	struct v9fs_inode *v9inode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	int omode;
+
+	p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
+	v9inode = V9FS_I(inode);
+	v9ses = v9fs_inode2v9ses(inode);
+	if (v9fs_proto_dotl(v9ses))
+		omode = v9fs_open_to_dotl_flags(file->f_flags);
+	else
+		omode = v9fs_uflags2omode(file->f_flags,
+					v9fs_proto_dotu(v9ses));
+	fid = file->private_data;
+	if (!fid) {
+		fid = v9fs_fid_clone(file_dentry(file));
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		err = p9_client_open(fid, omode);
+		if (err < 0) {
+			p9_client_clunk(fid);
+			return err;
+		}
+		if ((file->f_flags & O_APPEND) &&
+			(!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
+			generic_file_llseek(file, 0, SEEK_END);
+	}
+
+	file->private_data = fid;
+	mutex_lock(&v9inode->v_mutex);
+	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
+	    !v9inode->writeback_fid &&
+	    ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
+		/*
+		 * clone a fid and add it to writeback_fid
+		 * we do it during open time instead of
+		 * page dirty time via write_begin/page_mkwrite
+		 * because we want write after unlink usecase
+		 * to work.
+		 */
+		fid = v9fs_writeback_fid(file_dentry(file));
+		if (IS_ERR(fid)) {
+			err = PTR_ERR(fid);
+			mutex_unlock(&v9inode->v_mutex);
+			goto out_error;
+		}
+		v9inode->writeback_fid = (void *) fid;
+	}
+	mutex_unlock(&v9inode->v_mutex);
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
+		v9fs_cache_inode_set_cookie(inode, file);
+	return 0;
+out_error:
+	p9_client_clunk(file->private_data);
+	file->private_data = NULL;
+	return err;
+}
+
+/**
+ * v9fs_file_lock - lock a file (or directory)
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ * Bugs: this looks like a local only lock, we should extend into 9P
+ *       by using open exclusive
+ */
+
+static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	int res = 0;
+	struct inode *inode = file_inode(filp);
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		return -ENOLCK;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+
+	return res;
+}
+
+static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	struct p9_flock flock;
+	struct p9_fid *fid;
+	uint8_t status = P9_LOCK_ERROR;
+	int res = 0;
+	unsigned char fl_type;
+	struct v9fs_session_info *v9ses;
+
+	fid = filp->private_data;
+	BUG_ON(fid == NULL);
+
+	if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
+		BUG();
+
+	res = locks_lock_file_wait(filp, fl);
+	if (res < 0)
+		goto out;
+
+	/* convert posix lock to p9 tlock args */
+	memset(&flock, 0, sizeof(flock));
+	/* map the lock type */
+	switch (fl->fl_type) {
+	case F_RDLCK:
+		flock.type = P9_LOCK_TYPE_RDLCK;
+		break;
+	case F_WRLCK:
+		flock.type = P9_LOCK_TYPE_WRLCK;
+		break;
+	case F_UNLCK:
+		flock.type = P9_LOCK_TYPE_UNLCK;
+		break;
+	}
+	flock.start = fl->fl_start;
+	if (fl->fl_end == OFFSET_MAX)
+		flock.length = 0;
+	else
+		flock.length = fl->fl_end - fl->fl_start + 1;
+	flock.proc_id = fl->fl_pid;
+	flock.client_id = fid->clnt->name;
+	if (IS_SETLKW(cmd))
+		flock.flags = P9_LOCK_FLAGS_BLOCK;
+
+	v9ses = v9fs_inode2v9ses(file_inode(filp));
+
+	/*
+	 * if its a blocked request and we get P9_LOCK_BLOCKED as the status
+	 * for lock request, keep on trying
+	 */
+	for (;;) {
+		res = p9_client_lock_dotl(fid, &flock, &status);
+		if (res < 0)
+			goto out_unlock;
+
+		if (status != P9_LOCK_BLOCKED)
+			break;
+		if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
+			break;
+		if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
+				!= 0)
+			break;
+		/*
+		 * p9_client_lock_dotl overwrites flock.client_id with the
+		 * server message, free and reuse the client name
+		 */
+		if (flock.client_id != fid->clnt->name) {
+			kfree(flock.client_id);
+			flock.client_id = fid->clnt->name;
+		}
+	}
+
+	/* map 9p status to VFS status */
+	switch (status) {
+	case P9_LOCK_SUCCESS:
+		res = 0;
+		break;
+	case P9_LOCK_BLOCKED:
+		res = -EAGAIN;
+		break;
+	default:
+		WARN_ONCE(1, "unknown lock status code: %d\n", status);
+		/* fallthough */
+	case P9_LOCK_ERROR:
+	case P9_LOCK_GRACE:
+		res = -ENOLCK;
+		break;
+	}
+
+out_unlock:
+	/*
+	 * incase server returned error for lock request, revert
+	 * it locally
+	 */
+	if (res < 0 && fl->fl_type != F_UNLCK) {
+		fl_type = fl->fl_type;
+		fl->fl_type = F_UNLCK;
+		/* Even if this fails we want to return the remote error */
+		locks_lock_file_wait(filp, fl);
+		fl->fl_type = fl_type;
+	}
+	if (flock.client_id != fid->clnt->name)
+		kfree(flock.client_id);
+out:
+	return res;
+}
+
+static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
+{
+	struct p9_getlock glock;
+	struct p9_fid *fid;
+	int res = 0;
+
+	fid = filp->private_data;
+	BUG_ON(fid == NULL);
+
+	posix_test_lock(filp, fl);
+	/*
+	 * if we have a conflicting lock locally, no need to validate
+	 * with server
+	 */
+	if (fl->fl_type != F_UNLCK)
+		return res;
+
+	/* convert posix lock to p9 tgetlock args */
+	memset(&glock, 0, sizeof(glock));
+	glock.type  = P9_LOCK_TYPE_UNLCK;
+	glock.start = fl->fl_start;
+	if (fl->fl_end == OFFSET_MAX)
+		glock.length = 0;
+	else
+		glock.length = fl->fl_end - fl->fl_start + 1;
+	glock.proc_id = fl->fl_pid;
+	glock.client_id = fid->clnt->name;
+
+	res = p9_client_getlock_dotl(fid, &glock);
+	if (res < 0)
+		goto out;
+	/* map 9p lock type to os lock type */
+	switch (glock.type) {
+	case P9_LOCK_TYPE_RDLCK:
+		fl->fl_type = F_RDLCK;
+		break;
+	case P9_LOCK_TYPE_WRLCK:
+		fl->fl_type = F_WRLCK;
+		break;
+	case P9_LOCK_TYPE_UNLCK:
+		fl->fl_type = F_UNLCK;
+		break;
+	}
+	if (glock.type != P9_LOCK_TYPE_UNLCK) {
+		fl->fl_start = glock.start;
+		if (glock.length == 0)
+			fl->fl_end = OFFSET_MAX;
+		else
+			fl->fl_end = glock.start + glock.length - 1;
+		fl->fl_pid = glock.proc_id;
+	}
+out:
+	if (glock.client_id != fid->clnt->name)
+		kfree(glock.client_id);
+	return res;
+}
+
+/**
+ * v9fs_file_lock_dotl - lock a file (or directory)
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ */
+
+static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
+{
+	struct inode *inode = file_inode(filp);
+	int ret = -ENOLCK;
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
+		 filp, cmd, fl, filp);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		goto out_err;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+
+	if (IS_SETLK(cmd) || IS_SETLKW(cmd))
+		ret = v9fs_file_do_lock(filp, cmd, fl);
+	else if (IS_GETLK(cmd))
+		ret = v9fs_file_getlock(filp, fl);
+	else
+		ret = -EINVAL;
+out_err:
+	return ret;
+}
+
+/**
+ * v9fs_file_flock_dotl - lock a file
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ */
+
+static int v9fs_file_flock_dotl(struct file *filp, int cmd,
+	struct file_lock *fl)
+{
+	struct inode *inode = file_inode(filp);
+	int ret = -ENOLCK;
+
+	p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
+		 filp, cmd, fl, filp);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
+		goto out_err;
+
+	if (!(fl->fl_flags & FL_FLOCK))
+		goto out_err;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+	/* Convert flock to posix lock */
+	fl->fl_flags |= FL_POSIX;
+	fl->fl_flags ^= FL_FLOCK;
+
+	if (IS_SETLK(cmd) | IS_SETLKW(cmd))
+		ret = v9fs_file_do_lock(filp, cmd, fl);
+	else
+		ret = -EINVAL;
+out_err:
+	return ret;
+}
+
+/**
+ * v9fs_file_read - read from a file
+ * @filp: file pointer to read
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+static ssize_t
+v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	struct p9_fid *fid = iocb->ki_filp->private_data;
+	int ret, err = 0;
+
+	p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
+		 iov_iter_count(to), iocb->ki_pos);
+
+	ret = p9_client_read(fid, iocb->ki_pos, to, &err);
+	if (!ret)
+		return err;
+
+	iocb->ki_pos += ret;
+	return ret;
+}
+
+/**
+ * v9fs_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+static ssize_t
+v9fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct file *file = iocb->ki_filp;
+	ssize_t retval;
+	loff_t origin;
+	int err = 0;
+
+	retval = generic_write_checks(iocb, from);
+	if (retval <= 0)
+		return retval;
+
+	origin = iocb->ki_pos;
+	retval = p9_client_write(file->private_data, iocb->ki_pos, from, &err);
+	if (retval > 0) {
+		struct inode *inode = file_inode(file);
+		loff_t i_size;
+		unsigned long pg_start, pg_end;
+		pg_start = origin >> PAGE_CACHE_SHIFT;
+		pg_end = (origin + retval - 1) >> PAGE_CACHE_SHIFT;
+		if (inode->i_mapping && inode->i_mapping->nrpages)
+			invalidate_inode_pages2_range(inode->i_mapping,
+						      pg_start, pg_end);
+		iocb->ki_pos += retval;
+		i_size = i_size_read(inode);
+		if (iocb->ki_pos > i_size) {
+			inode_add_bytes(inode, iocb->ki_pos - i_size);
+			/*
+			 * Need to serialize against i_size_write() in
+			 * v9fs_stat2inode()
+			 */
+			v9fs_i_size_write(inode, iocb->ki_pos);
+		}
+		return retval;
+	}
+	return err;
+}
+
+static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
+			   int datasync)
+{
+	struct p9_fid *fid;
+	struct inode *inode = filp->f_mapping->host;
+	struct p9_wstat wstat;
+	int retval;
+
+	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (retval)
+		return retval;
+
+	mutex_lock(&inode->i_mutex);
+	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
+
+	fid = filp->private_data;
+	v9fs_blank_wstat(&wstat);
+
+	retval = p9_client_wstat(fid, &wstat);
+	mutex_unlock(&inode->i_mutex);
+
+	return retval;
+}
+
+int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
+			 int datasync)
+{
+	struct p9_fid *fid;
+	struct inode *inode = filp->f_mapping->host;
+	int retval;
+
+	retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (retval)
+		return retval;
+
+	mutex_lock(&inode->i_mutex);
+	p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
+
+	fid = filp->private_data;
+
+	retval = p9_client_fsync(fid, datasync);
+	mutex_unlock(&inode->i_mutex);
+
+	return retval;
+}
+
+static int
+v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	int retval;
+
+
+	retval = generic_file_mmap(filp, vma);
+	if (!retval)
+		vma->vm_ops = &v9fs_file_vm_ops;
+
+	return retval;
+}
+
+static int
+v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	int retval;
+	struct inode *inode;
+	struct v9fs_inode *v9inode;
+	struct p9_fid *fid;
+
+	inode = file_inode(filp);
+	v9inode = V9FS_I(inode);
+	mutex_lock(&v9inode->v_mutex);
+	if (!v9inode->writeback_fid &&
+	    (vma->vm_flags & VM_WRITE)) {
+		/*
+		 * clone a fid and add it to writeback_fid
+		 * we do it during mmap instead of
+		 * page dirty time via write_begin/page_mkwrite
+		 * because we want write after unlink usecase
+		 * to work.
+		 */
+		fid = v9fs_writeback_fid(file_dentry(filp));
+		if (IS_ERR(fid)) {
+			retval = PTR_ERR(fid);
+			mutex_unlock(&v9inode->v_mutex);
+			return retval;
+		}
+		v9inode->writeback_fid = (void *) fid;
+	}
+	mutex_unlock(&v9inode->v_mutex);
+
+	retval = generic_file_mmap(filp, vma);
+	if (!retval)
+		vma->vm_ops = &v9fs_mmap_file_vm_ops;
+
+	return retval;
+}
+
+static int
+v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct v9fs_inode *v9inode;
+	struct page *page = vmf->page;
+	struct file *filp = vma->vm_file;
+	struct inode *inode = file_inode(filp);
+
+
+	p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
+		 page, (unsigned long)filp->private_data);
+
+	/* Update file times before taking page lock */
+	file_update_time(filp);
+
+	v9inode = V9FS_I(inode);
+	/* make sure the cache has finished storing the page */
+	v9fs_fscache_wait_on_page_write(inode, page);
+	BUG_ON(!v9inode->writeback_fid);
+	lock_page(page);
+	if (page->mapping != inode->i_mapping)
+		goto out_unlock;
+	wait_for_stable_page(page);
+
+	return VM_FAULT_LOCKED;
+out_unlock:
+	unlock_page(page);
+	return VM_FAULT_NOPAGE;
+}
+
+/**
+ * v9fs_mmap_file_read - read from a file
+ * @filp: file pointer to read
+ * @data: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+static ssize_t
+v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	/* TODO: Check if there are dirty pages */
+	return v9fs_file_read_iter(iocb, to);
+}
+
+/**
+ * v9fs_mmap_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+static ssize_t
+v9fs_mmap_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	/*
+	 * TODO: invalidate mmaps on filp's inode between
+	 * offset and offset+count
+	 */
+	return v9fs_file_write_iter(iocb, from);
+}
+
+static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
+{
+	struct inode *inode;
+
+	struct writeback_control wbc = {
+		.nr_to_write = LONG_MAX,
+		.sync_mode = WB_SYNC_ALL,
+		.range_start = vma->vm_pgoff * PAGE_SIZE,
+		 /* absolute end, byte at end included */
+		.range_end = vma->vm_pgoff * PAGE_SIZE +
+			(vma->vm_end - vma->vm_start - 1),
+	};
+
+
+	p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
+
+	inode = file_inode(vma->vm_file);
+
+	if (!mapping_cap_writeback_dirty(inode->i_mapping))
+		wbc.nr_to_write = 0;
+
+	might_sleep();
+	sync_inode(inode, &wbc);
+}
+
+
+static const struct vm_operations_struct v9fs_file_vm_ops = {
+	.fault = filemap_fault,
+	.map_pages = filemap_map_pages,
+	.page_mkwrite = v9fs_vm_page_mkwrite,
+};
+
+static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
+	.close = v9fs_mmap_vm_close,
+	.fault = filemap_fault,
+	.map_pages = filemap_map_pages,
+	.page_mkwrite = v9fs_vm_page_mkwrite,
+};
+
+
+const struct file_operations v9fs_cached_file_operations = {
+	.llseek = generic_file_llseek,
+	.read_iter = generic_file_read_iter,
+	.write_iter = generic_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = v9fs_file_mmap,
+	.fsync = v9fs_file_fsync,
+};
+
+const struct file_operations v9fs_cached_file_operations_dotl = {
+	.llseek = generic_file_llseek,
+	.read_iter = generic_file_read_iter,
+	.write_iter = generic_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock_dotl,
+	.flock = v9fs_file_flock_dotl,
+	.mmap = v9fs_file_mmap,
+	.fsync = v9fs_file_fsync_dotl,
+};
+
+const struct file_operations v9fs_file_operations = {
+	.llseek = generic_file_llseek,
+	.read_iter = v9fs_file_read_iter,
+	.write_iter = v9fs_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = generic_file_readonly_mmap,
+	.fsync = v9fs_file_fsync,
+};
+
+const struct file_operations v9fs_file_operations_dotl = {
+	.llseek = generic_file_llseek,
+	.read_iter = v9fs_file_read_iter,
+	.write_iter = v9fs_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock_dotl,
+	.flock = v9fs_file_flock_dotl,
+	.mmap = generic_file_readonly_mmap,
+	.fsync = v9fs_file_fsync_dotl,
+};
+
+const struct file_operations v9fs_mmap_file_operations = {
+	.llseek = generic_file_llseek,
+	.read_iter = v9fs_mmap_file_read_iter,
+	.write_iter = v9fs_mmap_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = v9fs_mmap_file_mmap,
+	.fsync = v9fs_file_fsync,
+};
+
+const struct file_operations v9fs_mmap_file_operations_dotl = {
+	.llseek = generic_file_llseek,
+	.read_iter = v9fs_mmap_file_read_iter,
+	.write_iter = v9fs_mmap_file_write_iter,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock_dotl,
+	.flock = v9fs_file_flock_dotl,
+	.mmap = v9fs_mmap_file_mmap,
+	.fsync = v9fs_file_fsync_dotl,
+};

addons/9p/src/4.4.180/vfs_inode_dotl.c

@@ -0,0 +1,999 @@
+/*
+ *  linux/fs/9p/vfs_inode_dotl.c
+ *
+ * This file contains vfs inode ops for the 9P2000.L protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+#include "cache.h"
+#include "xattr.h"
+#include "acl.h"
+
+static int
+v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
+		    dev_t rdev);
+
+/**
+ * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
+ * new file system object. This checks the S_ISGID to determine the owning
+ * group of the new file system object.
+ */
+
+static kgid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
+{
+	BUG_ON(dir_inode == NULL);
+
+	if (dir_inode->i_mode & S_ISGID) {
+		/* set_gid bit is set.*/
+		return dir_inode->i_gid;
+	}
+	return current_fsgid();
+}
+
+static int v9fs_test_inode_dotl(struct inode *inode, void *data)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
+
+	/* don't match inode of different type */
+	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
+		return 0;
+
+	if (inode->i_generation != st->st_gen)
+		return 0;
+
+	/* compare qid details */
+	if (memcmp(&v9inode->qid.version,
+		   &st->qid.version, sizeof(v9inode->qid.version)))
+		return 0;
+
+	if (v9inode->qid.type != st->qid.type)
+		return 0;
+
+	if (v9inode->qid.path != st->qid.path)
+		return 0;
+	return 1;
+}
+
+/* Always get a new inode */
+static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
+{
+	return 0;
+}
+
+static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
+{
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+	struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;
+
+	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
+	inode->i_generation = st->st_gen;
+	return 0;
+}
+
+static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
+					struct p9_qid *qid,
+					struct p9_fid *fid,
+					struct p9_stat_dotl *st,
+					int new)
+{
+	int retval;
+	unsigned long i_ino;
+	struct inode *inode;
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+	int (*test)(struct inode *, void *);
+
+	if (new)
+		test = v9fs_test_new_inode_dotl;
+	else
+		test = v9fs_test_inode_dotl;
+
+	i_ino = v9fs_qid2ino(qid);
+	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+	/*
+	 * initialize the inode with the stat info
+	 * FIXME!! we may need support for stale inodes
+	 * later.
+	 */
+	inode->i_ino = i_ino;
+	retval = v9fs_init_inode(v9ses, inode,
+				 st->st_mode, new_decode_dev(st->st_rdev));
+	if (retval)
+		goto error;
+
+	v9fs_stat2inode_dotl(st, inode, 0);
+	v9fs_cache_inode_get_cookie(inode);
+	retval = v9fs_get_acl(inode, fid);
+	if (retval)
+		goto error;
+
+	unlock_new_inode(inode);
+	return inode;
+error:
+	iget_failed(inode);
+	return ERR_PTR(retval);
+
+}
+
+struct inode *
+v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+			 struct super_block *sb, int new)
+{
+	struct p9_stat_dotl *st;
+	struct inode *inode = NULL;
+
+	st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
+	if (IS_ERR(st))
+		return ERR_CAST(st);
+
+	inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
+	kfree(st);
+	return inode;
+}
+
+struct dotl_openflag_map {
+	int open_flag;
+	int dotl_flag;
+};
+
+static int v9fs_mapped_dotl_flags(int flags)
+{
+	int i;
+	int rflags = 0;
+	struct dotl_openflag_map dotl_oflag_map[] = {
+		{ O_CREAT,	P9_DOTL_CREATE },
+		{ O_EXCL,	P9_DOTL_EXCL },
+		{ O_NOCTTY,	P9_DOTL_NOCTTY },
+		{ O_APPEND,	P9_DOTL_APPEND },
+		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
+		{ O_DSYNC,	P9_DOTL_DSYNC },
+		{ FASYNC,	P9_DOTL_FASYNC },
+		{ O_DIRECT,	P9_DOTL_DIRECT },
+		{ O_LARGEFILE,	P9_DOTL_LARGEFILE },
+		{ O_DIRECTORY,	P9_DOTL_DIRECTORY },
+		{ O_NOFOLLOW,	P9_DOTL_NOFOLLOW },
+		{ O_NOATIME,	P9_DOTL_NOATIME },
+		{ O_CLOEXEC,	P9_DOTL_CLOEXEC },
+		{ O_SYNC,	P9_DOTL_SYNC},
+	};
+	for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
+		if (flags & dotl_oflag_map[i].open_flag)
+			rflags |= dotl_oflag_map[i].dotl_flag;
+	}
+	return rflags;
+}
+
+/**
+ * v9fs_open_to_dotl_flags- convert Linux specific open flags to
+ * plan 9 open flag.
+ * @flags: flags to convert
+ */
+int v9fs_open_to_dotl_flags(int flags)
+{
+	int rflags = 0;
+
+	/*
+	 * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
+	 * and P9_DOTL_NOACCESS
+	 */
+	rflags |= flags & O_ACCMODE;
+	rflags |= v9fs_mapped_dotl_flags(flags);
+
+	return rflags;
+}
+
+/**
+ * v9fs_vfs_create_dotl - VFS hook to create files for 9P2000.L protocol.
+ * @dir: directory inode that is being created
+ * @dentry:  dentry that is being deleted
+ * @omode: create permissions
+ *
+ */
+
+static int
+v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
+		bool excl)
+{
+	return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
+}
+
+static int
+v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
+			  struct file *file, unsigned flags, umode_t omode,
+			  int *opened)
+{
+	int err = 0;
+	kgid_t gid;
+	umode_t mode;
+	char *name = NULL;
+	struct p9_qid qid;
+	struct inode *inode;
+	struct p9_fid *fid = NULL;
+	struct v9fs_inode *v9inode;
+	struct p9_fid *dfid, *ofid, *inode_fid;
+	struct v9fs_session_info *v9ses;
+	struct posix_acl *pacl = NULL, *dacl = NULL;
+	struct dentry *res = NULL;
+
+	if (d_unhashed(dentry)) {
+		res = v9fs_vfs_lookup(dir, dentry, 0);
+		if (IS_ERR(res))
+			return PTR_ERR(res);
+
+		if (res)
+			dentry = res;
+	}
+
+	/* Only creates */
+	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
+		return	finish_no_open(file, res);
+
+	v9ses = v9fs_inode2v9ses(dir);
+
+	name = (char *) dentry->d_name.name;
+	p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
+		 name, flags, omode);
+
+	dfid = v9fs_fid_lookup(dentry->d_parent);
+	if (IS_ERR(dfid)) {
+		err = PTR_ERR(dfid);
+		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
+		goto out;
+	}
+
+	/* clone a fid to use for creation */
+	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	if (IS_ERR(ofid)) {
+		err = PTR_ERR(ofid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
+		goto out;
+	}
+
+	gid = v9fs_get_fsgid_for_create(dir);
+
+	mode = omode;
+	/* Update mode based on ACL value */
+	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
+	if (err) {
+		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
+			 err);
+		goto error;
+	}
+	err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
+				    mode, gid, &qid);
+	if (err < 0) {
+		p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
+			 err);
+		goto error;
+	}
+	v9fs_invalidate_inode_attr(dir);
+
+	/* instantiate inode and assign the unopened fid to the dentry */
+	fid = p9_client_walk(dfid, 1, &name, 1);
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
+		fid = NULL;
+		goto error;
+	}
+	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
+		goto error;
+	}
+	/* Now set the ACL based on the default value */
+	v9fs_set_create_acl(inode, fid, dacl, pacl);
+
+	v9fs_fid_add(dentry, fid);
+	d_instantiate(dentry, inode);
+
+	v9inode = V9FS_I(inode);
+	mutex_lock(&v9inode->v_mutex);
+	if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
+	    !v9inode->writeback_fid &&
+	    ((flags & O_ACCMODE) != O_RDONLY)) {
+		/*
+		 * clone a fid and add it to writeback_fid
+		 * we do it during open time instead of
+		 * page dirty time via write_begin/page_mkwrite
+		 * because we want write after unlink usecase
+		 * to work.
+		 */
+		inode_fid = v9fs_writeback_fid(dentry);
+		if (IS_ERR(inode_fid)) {
+			err = PTR_ERR(inode_fid);
+			mutex_unlock(&v9inode->v_mutex);
+			goto err_clunk_old_fid;
+		}
+		v9inode->writeback_fid = (void *) inode_fid;
+	}
+	mutex_unlock(&v9inode->v_mutex);
+	/* Since we are opening a file, assign the open fid to the file */
+	err = finish_open(file, dentry, generic_file_open, opened);
+	if (err)
+		goto err_clunk_old_fid;
+	file->private_data = ofid;
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
+		v9fs_cache_inode_set_cookie(inode, file);
+	*opened |= FILE_CREATED;
+out:
+	v9fs_put_acl(dacl, pacl);
+	dput(res);
+	return err;
+
+error:
+	if (fid)
+		p9_client_clunk(fid);
+err_clunk_old_fid:
+	if (ofid)
+		p9_client_clunk(ofid);
+	goto out;
+}
+
+/**
+ * v9fs_vfs_mkdir_dotl - VFS mkdir hook to create a directory
+ * @dir:  inode that is being unlinked
+ * @dentry: dentry that is being unlinked
+ * @omode: mode for new directory
+ *
+ */
+
+static int v9fs_vfs_mkdir_dotl(struct inode *dir,
+			       struct dentry *dentry, umode_t omode)
+{
+	int err;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid = NULL, *dfid = NULL;
+	kgid_t gid;
+	char *name;
+	umode_t mode;
+	struct inode *inode;
+	struct p9_qid qid;
+	struct dentry *dir_dentry;
+	struct posix_acl *dacl = NULL, *pacl = NULL;
+
+	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
+	err = 0;
+	v9ses = v9fs_inode2v9ses(dir);
+
+	omode |= S_IFDIR;
+	if (dir->i_mode & S_ISGID)
+		omode |= S_ISGID;
+
+	dir_dentry = dentry->d_parent;
+	dfid = v9fs_fid_lookup(dir_dentry);
+	if (IS_ERR(dfid)) {
+		err = PTR_ERR(dfid);
+		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
+		dfid = NULL;
+		goto error;
+	}
+
+	gid = v9fs_get_fsgid_for_create(dir);
+	mode = omode;
+	/* Update mode based on ACL value */
+	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
+	if (err) {
+		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
+			 err);
+		goto error;
+	}
+	name = (char *) dentry->d_name.name;
+	err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
+	if (err < 0)
+		goto error;
+
+	fid = p9_client_walk(dfid, 1, &name, 1);
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
+			 err);
+		fid = NULL;
+		goto error;
+	}
+
+	/* instantiate inode and assign the unopened fid to the dentry */
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
+				 err);
+			goto error;
+		}
+		v9fs_fid_add(dentry, fid);
+		v9fs_set_create_acl(inode, fid, dacl, pacl);
+		d_instantiate(dentry, inode);
+		fid = NULL;
+		err = 0;
+	} else {
+		/*
+		 * Not in cached mode. No need to populate
+		 * inode with stat. We need to get an inode
+		 * so that we can set the acl with dentry
+		 */
+		inode = v9fs_get_inode(dir->i_sb, mode, 0);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			goto error;
+		}
+		v9fs_set_create_acl(inode, fid, dacl, pacl);
+		d_instantiate(dentry, inode);
+	}
+	inc_nlink(dir);
+	v9fs_invalidate_inode_attr(dir);
+error:
+	if (fid)
+		p9_client_clunk(fid);
+	v9fs_put_acl(dacl, pacl);
+	return err;
+}
+
+static int
+v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
+		 struct kstat *stat)
+{
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_stat_dotl *st;
+
+	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
+	v9ses = v9fs_dentry2v9ses(dentry);
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+		generic_fillattr(d_inode(dentry), stat);
+		return 0;
+	}
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	/* Ask for all the fields in stat structure. Server will return
+	 * whatever it supports
+	 */
+
+	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
+	if (IS_ERR(st))
+		return PTR_ERR(st);
+
+	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
+	generic_fillattr(d_inode(dentry), stat);
+	/* Change block size to what the server returned */
+	stat->blksize = st->st_blksize;
+
+	kfree(st);
+	return 0;
+}
+
+/*
+ * Attribute flags.
+ */
+#define P9_ATTR_MODE		(1 << 0)
+#define P9_ATTR_UID		(1 << 1)
+#define P9_ATTR_GID		(1 << 2)
+#define P9_ATTR_SIZE		(1 << 3)
+#define P9_ATTR_ATIME		(1 << 4)
+#define P9_ATTR_MTIME		(1 << 5)
+#define P9_ATTR_CTIME		(1 << 6)
+#define P9_ATTR_ATIME_SET	(1 << 7)
+#define P9_ATTR_MTIME_SET	(1 << 8)
+
+struct dotl_iattr_map {
+	int iattr_valid;
+	int p9_iattr_valid;
+};
+
+static int v9fs_mapped_iattr_valid(int iattr_valid)
+{
+	int i;
+	int p9_iattr_valid = 0;
+	struct dotl_iattr_map dotl_iattr_map[] = {
+		{ ATTR_MODE,		P9_ATTR_MODE },
+		{ ATTR_UID,		P9_ATTR_UID },
+		{ ATTR_GID,		P9_ATTR_GID },
+		{ ATTR_SIZE,		P9_ATTR_SIZE },
+		{ ATTR_ATIME,		P9_ATTR_ATIME },
+		{ ATTR_MTIME,		P9_ATTR_MTIME },
+		{ ATTR_CTIME,		P9_ATTR_CTIME },
+		{ ATTR_ATIME_SET,	P9_ATTR_ATIME_SET },
+		{ ATTR_MTIME_SET,	P9_ATTR_MTIME_SET },
+	};
+	for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
+		if (iattr_valid & dotl_iattr_map[i].iattr_valid)
+			p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
+	}
+	return p9_iattr_valid;
+}
+
+/**
+ * v9fs_vfs_setattr_dotl - set file metadata
+ * @dentry: file whose metadata to set
+ * @iattr: metadata assignment structure
+ *
+ */
+
+int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
+{
+	int retval;
+	struct p9_fid *fid;
+	struct p9_iattr_dotl p9attr;
+	struct inode *inode = d_inode(dentry);
+
+	p9_debug(P9_DEBUG_VFS, "\n");
+
+	retval = inode_change_ok(inode, iattr);
+	if (retval)
+		return retval;
+
+	p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
+	p9attr.mode = iattr->ia_mode;
+	p9attr.uid = iattr->ia_uid;
+	p9attr.gid = iattr->ia_gid;
+	p9attr.size = iattr->ia_size;
+	p9attr.atime_sec = iattr->ia_atime.tv_sec;
+	p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
+	p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
+	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	/* Write all dirty data */
+	if (S_ISREG(inode->i_mode))
+		filemap_write_and_wait(inode->i_mapping);
+
+	retval = p9_client_setattr(fid, &p9attr);
+	if (retval < 0)
+		return retval;
+
+	if ((iattr->ia_valid & ATTR_SIZE) &&
+	    iattr->ia_size != i_size_read(inode))
+		truncate_setsize(inode, iattr->ia_size);
+
+	v9fs_invalidate_inode_attr(inode);
+	setattr_copy(inode, iattr);
+	mark_inode_dirty(inode);
+	if (iattr->ia_valid & ATTR_MODE) {
+		/* We also want to update ACL when we update mode bits */
+		retval = v9fs_acl_chmod(inode, fid);
+		if (retval < 0)
+			return retval;
+	}
+	return 0;
+}
+
+/**
+ * v9fs_stat2inode_dotl - populate an inode structure with stat info
+ * @stat: stat structure
+ * @inode: inode to populate
+ * @flags: ctrl flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
+ *
+ */
+
+void
+v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
+		      unsigned int flags)
+{
+	umode_t mode;
+	struct v9fs_inode *v9inode = V9FS_I(inode);
+
+	if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
+		inode->i_atime.tv_sec = stat->st_atime_sec;
+		inode->i_atime.tv_nsec = stat->st_atime_nsec;
+		inode->i_mtime.tv_sec = stat->st_mtime_sec;
+		inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
+		inode->i_ctime.tv_sec = stat->st_ctime_sec;
+		inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
+		inode->i_uid = stat->st_uid;
+		inode->i_gid = stat->st_gid;
+		set_nlink(inode, stat->st_nlink);
+
+		mode = stat->st_mode & S_IALLUGO;
+		mode |= inode->i_mode & ~S_IALLUGO;
+		inode->i_mode = mode;
+
+		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
+			v9fs_i_size_write(inode, stat->st_size);
+		inode->i_blocks = stat->st_blocks;
+	} else {
+		if (stat->st_result_mask & P9_STATS_ATIME) {
+			inode->i_atime.tv_sec = stat->st_atime_sec;
+			inode->i_atime.tv_nsec = stat->st_atime_nsec;
+		}
+		if (stat->st_result_mask & P9_STATS_MTIME) {
+			inode->i_mtime.tv_sec = stat->st_mtime_sec;
+			inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
+		}
+		if (stat->st_result_mask & P9_STATS_CTIME) {
+			inode->i_ctime.tv_sec = stat->st_ctime_sec;
+			inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
+		}
+		if (stat->st_result_mask & P9_STATS_UID)
+			inode->i_uid = stat->st_uid;
+		if (stat->st_result_mask & P9_STATS_GID)
+			inode->i_gid = stat->st_gid;
+		if (stat->st_result_mask & P9_STATS_NLINK)
+			set_nlink(inode, stat->st_nlink);
+		if (stat->st_result_mask & P9_STATS_MODE) {
+			inode->i_mode = stat->st_mode;
+			if ((S_ISBLK(inode->i_mode)) ||
+						(S_ISCHR(inode->i_mode)))
+				init_special_inode(inode, inode->i_mode,
+								inode->i_rdev);
+		}
+		if (stat->st_result_mask & P9_STATS_RDEV)
+			inode->i_rdev = new_decode_dev(stat->st_rdev);
+		if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE) &&
+		    stat->st_result_mask & P9_STATS_SIZE)
+			v9fs_i_size_write(inode, stat->st_size);
+		if (stat->st_result_mask & P9_STATS_BLOCKS)
+			inode->i_blocks = stat->st_blocks;
+	}
+	if (stat->st_result_mask & P9_STATS_GEN)
+		inode->i_generation = stat->st_gen;
+
+	/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
+	 * because the inode structure does not have fields for them.
+	 */
+	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
+}
+
+static int
+v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
+		const char *symname)
+{
+	int err;
+	kgid_t gid;
+	char *name;
+	struct p9_qid qid;
+	struct inode *inode;
+	struct p9_fid *dfid;
+	struct p9_fid *fid = NULL;
+	struct v9fs_session_info *v9ses;
+
+	name = (char *) dentry->d_name.name;
+	p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
+	v9ses = v9fs_inode2v9ses(dir);
+
+	dfid = v9fs_fid_lookup(dentry->d_parent);
+	if (IS_ERR(dfid)) {
+		err = PTR_ERR(dfid);
+		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
+		return err;
+	}
+
+	gid = v9fs_get_fsgid_for_create(dir);
+
+	/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
+	err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
+
+	if (err < 0) {
+		p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
+		goto error;
+	}
+
+	v9fs_invalidate_inode_attr(dir);
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+		/* Now walk from the parent so we can get an unopened fid. */
+		fid = p9_client_walk(dfid, 1, &name, 1);
+		if (IS_ERR(fid)) {
+			err = PTR_ERR(fid);
+			p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
+				 err);
+			fid = NULL;
+			goto error;
+		}
+
+		/* instantiate inode and assign the unopened fid to dentry */
+		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
+				 err);
+			goto error;
+		}
+		v9fs_fid_add(dentry, fid);
+		d_instantiate(dentry, inode);
+		fid = NULL;
+		err = 0;
+	} else {
+		/* Not in cached mode. No need to populate inode with stat */
+		inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			goto error;
+		}
+		d_instantiate(dentry, inode);
+	}
+
+error:
+	if (fid)
+		p9_client_clunk(fid);
+
+	return err;
+}
+
+/**
+ * v9fs_vfs_link_dotl - create a hardlink for dotl
+ * @old_dentry: dentry for file to link to
+ * @dir: inode destination for new link
+ * @dentry: dentry for link
+ *
+ */
+
+static int
+v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
+		struct dentry *dentry)
+{
+	int err;
+	struct dentry *dir_dentry;
+	struct p9_fid *dfid, *oldfid;
+	struct v9fs_session_info *v9ses;
+
+	p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %pd, new_name: %pd\n",
+		 dir->i_ino, old_dentry, dentry);
+
+	v9ses = v9fs_inode2v9ses(dir);
+	dir_dentry = dentry->d_parent;
+	dfid = v9fs_fid_lookup(dir_dentry);
+	if (IS_ERR(dfid))
+		return PTR_ERR(dfid);
+
+	oldfid = v9fs_fid_lookup(old_dentry);
+	if (IS_ERR(oldfid))
+		return PTR_ERR(oldfid);
+
+	err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
+
+	if (err < 0) {
+		p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
+		return err;
+	}
+
+	v9fs_invalidate_inode_attr(dir);
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+		/* Get the latest stat info from server. */
+		struct p9_fid *fid;
+		fid = v9fs_fid_lookup(old_dentry);
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		v9fs_refresh_inode_dotl(fid, d_inode(old_dentry));
+	}
+	ihold(d_inode(old_dentry));
+	d_instantiate(dentry, d_inode(old_dentry));
+
+	return err;
+}
+
+/**
+ * v9fs_vfs_mknod_dotl - create a special file
+ * @dir: inode destination for new link
+ * @dentry: dentry for file
+ * @omode: mode for creation
+ * @rdev: device associated with special file
+ *
+ */
+static int
+v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
+		dev_t rdev)
+{
+	int err;
+	kgid_t gid;
+	char *name;
+	umode_t mode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid = NULL, *dfid = NULL;
+	struct inode *inode;
+	struct p9_qid qid;
+	struct dentry *dir_dentry;
+	struct posix_acl *dacl = NULL, *pacl = NULL;
+
+	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n",
+		 dir->i_ino, dentry, omode,
+		 MAJOR(rdev), MINOR(rdev));
+
+	v9ses = v9fs_inode2v9ses(dir);
+	dir_dentry = dentry->d_parent;
+	dfid = v9fs_fid_lookup(dir_dentry);
+	if (IS_ERR(dfid)) {
+		err = PTR_ERR(dfid);
+		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
+		dfid = NULL;
+		goto error;
+	}
+
+	gid = v9fs_get_fsgid_for_create(dir);
+	mode = omode;
+	/* Update mode based on ACL value */
+	err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
+	if (err) {
+		p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
+			 err);
+		goto error;
+	}
+	name = (char *) dentry->d_name.name;
+
+	err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
+	if (err < 0)
+		goto error;
+
+	v9fs_invalidate_inode_attr(dir);
+	fid = p9_client_walk(dfid, 1, &name, 1);
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
+			 err);
+		fid = NULL;
+		goto error;
+	}
+
+	/* instantiate inode and assign the unopened fid to the dentry */
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
+				 err);
+			goto error;
+		}
+		v9fs_set_create_acl(inode, fid, dacl, pacl);
+		v9fs_fid_add(dentry, fid);
+		d_instantiate(dentry, inode);
+		fid = NULL;
+		err = 0;
+	} else {
+		/*
+		 * Not in cached mode. No need to populate inode with stat.
+		 * socket syscall returns a fd, so we need instantiate
+		 */
+		inode = v9fs_get_inode(dir->i_sb, mode, rdev);
+		if (IS_ERR(inode)) {
+			err = PTR_ERR(inode);
+			goto error;
+		}
+		v9fs_set_create_acl(inode, fid, dacl, pacl);
+		d_instantiate(dentry, inode);
+	}
+error:
+	if (fid)
+		p9_client_clunk(fid);
+	v9fs_put_acl(dacl, pacl);
+	return err;
+}
+
+/**
+ * v9fs_vfs_follow_link_dotl - follow a symlink path
+ * @dentry: dentry for symlink
+ * @cookie: place to pass the data to put_link()
+ */
+
+static const char *
+v9fs_vfs_follow_link_dotl(struct dentry *dentry, void **cookie)
+{
+	struct p9_fid *fid = v9fs_fid_lookup(dentry);
+	char *target;
+	int retval;
+
+	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
+
+	if (IS_ERR(fid))
+		return ERR_CAST(fid);
+	retval = p9_client_readlink(fid, &target);
+	if (retval)
+		return ERR_PTR(retval);
+	return *cookie = target;
+}
+
+int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
+{
+	struct p9_stat_dotl *st;
+	struct v9fs_session_info *v9ses;
+	unsigned int flags;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
+	if (IS_ERR(st))
+		return PTR_ERR(st);
+	/*
+	 * Don't update inode if the file type is different
+	 */
+	if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
+		goto out;
+
+	/*
+	 * We don't want to refresh inode->i_size,
+	 * because we may have cached data
+	 */
+	flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ?
+		V9FS_STAT2INODE_KEEP_ISIZE : 0;
+	v9fs_stat2inode_dotl(st, inode, flags);
+out:
+	kfree(st);
+	return 0;
+}
+
+const struct inode_operations v9fs_dir_inode_operations_dotl = {
+	.create = v9fs_vfs_create_dotl,
+	.atomic_open = v9fs_vfs_atomic_open_dotl,
+	.lookup = v9fs_vfs_lookup,
+	.link = v9fs_vfs_link_dotl,
+	.symlink = v9fs_vfs_symlink_dotl,
+	.unlink = v9fs_vfs_unlink,
+	.mkdir = v9fs_vfs_mkdir_dotl,
+	.rmdir = v9fs_vfs_rmdir,
+	.mknod = v9fs_vfs_mknod_dotl,
+	.rename = v9fs_vfs_rename,
+	.getattr = v9fs_vfs_getattr_dotl,
+	.setattr = v9fs_vfs_setattr_dotl,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
+	.removexattr = generic_removexattr,
+	.listxattr = v9fs_listxattr,
+	.get_acl = v9fs_iop_get_acl,
+};
+
+const struct inode_operations v9fs_file_inode_operations_dotl = {
+	.getattr = v9fs_vfs_getattr_dotl,
+	.setattr = v9fs_vfs_setattr_dotl,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
+	.removexattr = generic_removexattr,
+	.listxattr = v9fs_listxattr,
+	.get_acl = v9fs_iop_get_acl,
+};
+
+const struct inode_operations v9fs_symlink_inode_operations_dotl = {
+	.readlink = generic_readlink,
+	.follow_link = v9fs_vfs_follow_link_dotl,
+	.put_link = kfree_put_link,
+	.getattr = v9fs_vfs_getattr_dotl,
+	.setattr = v9fs_vfs_setattr_dotl,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
+	.removexattr = generic_removexattr,
+	.listxattr = v9fs_listxattr,
+};

addons/9p/src/4.4.180/vfs_super.c

@@ -0,0 +1,366 @@
+/*
+ *  linux/fs/9p/vfs_super.c
+ *
+ * This file contians superblock ops for 9P2000. It is intended that
+ * you mount this file system on directories.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/statfs.h>
+#include <linux/magic.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+#include "xattr.h"
+#include "acl.h"
+
+static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl;
+
+/**
+ * v9fs_set_super - set the superblock
+ * @s: super block
+ * @data: file system specific data
+ *
+ */
+
+static int v9fs_set_super(struct super_block *s, void *data)
+{
+	s->s_fs_info = data;
+	return set_anon_super(s, data);
+}
+
+/**
+ * v9fs_fill_super - populate superblock with info
+ * @sb: superblock
+ * @v9ses: session information
+ * @flags: flags propagated from v9fs_mount()
+ *
+ */
+
+static void
+v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
+		int flags, void *data)
+{
+	sb->s_maxbytes = MAX_LFS_FILESIZE;
+	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
+	sb->s_blocksize = 1 << sb->s_blocksize_bits;
+	sb->s_magic = V9FS_MAGIC;
+	if (v9fs_proto_dotl(v9ses)) {
+		sb->s_op = &v9fs_super_ops_dotl;
+		sb->s_xattr = v9fs_xattr_handlers;
+	} else
+		sb->s_op = &v9fs_super_ops;
+	sb->s_bdi = &v9ses->bdi;
+	if (v9ses->cache)
+		sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_CACHE_SIZE;
+
+	sb->s_flags |= MS_ACTIVE | MS_DIRSYNC | MS_NOATIME;
+	if (!v9ses->cache)
+		sb->s_flags |= MS_SYNCHRONOUS;
+
+#ifdef CONFIG_9P_FS_POSIX_ACL
+	if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
+		sb->s_flags |= MS_POSIXACL;
+#endif
+
+	save_mount_options(sb, data);
+}
+
+/**
+ * v9fs_mount - mount a superblock
+ * @fs_type: file system type
+ * @flags: mount flags
+ * @dev_name: device name that was mounted
+ * @data: mount options
+ *
+ */
+
+static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
+		       const char *dev_name, void *data)
+{
+	struct super_block *sb = NULL;
+	struct inode *inode = NULL;
+	struct dentry *root = NULL;
+	struct v9fs_session_info *v9ses = NULL;
+	umode_t mode = S_IRWXUGO | S_ISVTX;
+	struct p9_fid *fid;
+	int retval = 0;
+
+	p9_debug(P9_DEBUG_VFS, "\n");
+
+	v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
+	if (!v9ses)
+		return ERR_PTR(-ENOMEM);
+
+	fid = v9fs_session_init(v9ses, dev_name, data);
+	if (IS_ERR(fid)) {
+		retval = PTR_ERR(fid);
+		goto free_session;
+	}
+
+	sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses);
+	if (IS_ERR(sb)) {
+		retval = PTR_ERR(sb);
+		goto clunk_fid;
+	}
+	v9fs_fill_super(sb, v9ses, flags, data);
+
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
+		sb->s_d_op = &v9fs_cached_dentry_operations;
+	else
+		sb->s_d_op = &v9fs_dentry_operations;
+
+	inode = v9fs_get_inode(sb, S_IFDIR | mode, 0);
+	if (IS_ERR(inode)) {
+		retval = PTR_ERR(inode);
+		goto release_sb;
+	}
+
+	root = d_make_root(inode);
+	if (!root) {
+		retval = -ENOMEM;
+		goto release_sb;
+	}
+	sb->s_root = root;
+	if (v9fs_proto_dotl(v9ses)) {
+		struct p9_stat_dotl *st = NULL;
+		st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
+		if (IS_ERR(st)) {
+			retval = PTR_ERR(st);
+			goto release_sb;
+		}
+		d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
+		v9fs_stat2inode_dotl(st, d_inode(root), 0);
+		kfree(st);
+	} else {
+		struct p9_wstat *st = NULL;
+		st = p9_client_stat(fid);
+		if (IS_ERR(st)) {
+			retval = PTR_ERR(st);
+			goto release_sb;
+		}
+
+		d_inode(root)->i_ino = v9fs_qid2ino(&st->qid);
+		v9fs_stat2inode(st, d_inode(root), sb, 0);
+
+		p9stat_free(st);
+		kfree(st);
+	}
+	retval = v9fs_get_acl(inode, fid);
+	if (retval)
+		goto release_sb;
+	v9fs_fid_add(root, fid);
+
+	p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
+	return dget(sb->s_root);
+
+clunk_fid:
+	p9_client_clunk(fid);
+	v9fs_session_close(v9ses);
+free_session:
+	kfree(v9ses);
+	return ERR_PTR(retval);
+
+release_sb:
+	/*
+	 * we will do the session_close and root dentry release
+	 * in the below call. But we need to clunk fid, because we haven't
+	 * attached the fid to dentry so it won't get clunked
+	 * automatically.
+	 */
+	p9_client_clunk(fid);
+	deactivate_locked_super(sb);
+	return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_kill_super - Kill Superblock
+ * @s: superblock
+ *
+ */
+
+static void v9fs_kill_super(struct super_block *s)
+{
+	struct v9fs_session_info *v9ses = s->s_fs_info;
+
+	p9_debug(P9_DEBUG_VFS, " %p\n", s);
+
+	kill_anon_super(s);
+
+	v9fs_session_cancel(v9ses);
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+	s->s_fs_info = NULL;
+	p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
+}
+
+static void
+v9fs_umount_begin(struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses;
+
+	v9ses = sb->s_fs_info;
+	v9fs_session_begin_cancel(v9ses);
+}
+
+static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_rstatfs rs;
+	int res;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid)) {
+		res = PTR_ERR(fid);
+		goto done;
+	}
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	if (v9fs_proto_dotl(v9ses)) {
+		res = p9_client_statfs(fid, &rs);
+		if (res == 0) {
+			buf->f_type = rs.type;
+			buf->f_bsize = rs.bsize;
+			buf->f_blocks = rs.blocks;
+			buf->f_bfree = rs.bfree;
+			buf->f_bavail = rs.bavail;
+			buf->f_files = rs.files;
+			buf->f_ffree = rs.ffree;
+			buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL;
+			buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL;
+			buf->f_namelen = rs.namelen;
+		}
+		if (res != -ENOSYS)
+			goto done;
+	}
+	res = simple_statfs(dentry, buf);
+done:
+	return res;
+}
+
+static int v9fs_drop_inode(struct inode *inode)
+{
+	struct v9fs_session_info *v9ses;
+	v9ses = v9fs_inode2v9ses(inode);
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
+		return generic_drop_inode(inode);
+	/*
+	 * in case of non cached mode always drop the
+	 * the inode because we want the inode attribute
+	 * to always match that on the server.
+	 */
+	return 1;
+}
+
+static int v9fs_write_inode(struct inode *inode,
+			    struct writeback_control *wbc)
+{
+	int ret;
+	struct p9_wstat wstat;
+	struct v9fs_inode *v9inode;
+	/*
+	 * send an fsync request to server irrespective of
+	 * wbc->sync_mode.
+	 */
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
+	v9inode = V9FS_I(inode);
+	if (!v9inode->writeback_fid)
+		return 0;
+	v9fs_blank_wstat(&wstat);
+
+	ret = p9_client_wstat(v9inode->writeback_fid, &wstat);
+	if (ret < 0) {
+		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+		return ret;
+	}
+	return 0;
+}
+
+static int v9fs_write_inode_dotl(struct inode *inode,
+				 struct writeback_control *wbc)
+{
+	int ret;
+	struct v9fs_inode *v9inode;
+	/*
+	 * send an fsync request to server irrespective of
+	 * wbc->sync_mode.
+	 */
+	v9inode = V9FS_I(inode);
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p, writeback_fid %p\n",
+		 __func__, inode, v9inode->writeback_fid);
+	if (!v9inode->writeback_fid)
+		return 0;
+
+	ret = p9_client_fsync(v9inode->writeback_fid, 0);
+	if (ret < 0) {
+		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
+		return ret;
+	}
+	return 0;
+}
+
+static const struct super_operations v9fs_super_ops = {
+	.alloc_inode = v9fs_alloc_inode,
+	.destroy_inode = v9fs_destroy_inode,
+	.statfs = simple_statfs,
+	.evict_inode = v9fs_evict_inode,
+	.show_options = generic_show_options,
+	.umount_begin = v9fs_umount_begin,
+	.write_inode = v9fs_write_inode,
+};
+
+static const struct super_operations v9fs_super_ops_dotl = {
+	.alloc_inode = v9fs_alloc_inode,
+	.destroy_inode = v9fs_destroy_inode,
+	.statfs = v9fs_statfs,
+	.drop_inode = v9fs_drop_inode,
+	.evict_inode = v9fs_evict_inode,
+	.show_options = generic_show_options,
+	.umount_begin = v9fs_umount_begin,
+	.write_inode = v9fs_write_inode_dotl,
+};
+
+struct file_system_type v9fs_fs_type = {
+	.name = "9p",
+	.mount = v9fs_mount,
+	.kill_sb = v9fs_kill_super,
+	.owner = THIS_MODULE,
+	.fs_flags = FS_RENAME_DOES_D_MOVE,
+};
+MODULE_ALIAS_FS("9p");

addons/9p/src/4.4.180/xattr.c

@@ -0,0 +1,195 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "fid.h"
+#include "xattr.h"
+
+ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
+			   void *buffer, size_t buffer_size)
+{
+	ssize_t retval;
+	u64 attr_size;
+	struct p9_fid *attr_fid;
+	struct kvec kvec = {.iov_base = buffer, .iov_len = buffer_size};
+	struct iov_iter to;
+	int err;
+
+	iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buffer_size);
+
+	attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
+	if (IS_ERR(attr_fid)) {
+		retval = PTR_ERR(attr_fid);
+		p9_debug(P9_DEBUG_VFS, "p9_client_attrwalk failed %zd\n",
+			 retval);
+		return retval;
+	}
+	if (attr_size > buffer_size) {
+		if (!buffer_size) /* request to get the attr_size */
+			retval = attr_size;
+		else
+			retval = -ERANGE;
+	} else {
+		iov_iter_truncate(&to, attr_size);
+		retval = p9_client_read(attr_fid, 0, &to, &err);
+		if (err)
+			retval = err;
+	}
+	p9_client_clunk(attr_fid);
+	return retval;
+}
+
+
+/*
+ * v9fs_xattr_get()
+ *
+ * Copy an extended attribute into the buffer
+ * provided, or compute the buffer size required.
+ * Buffer is NULL to compute the size of the buffer required.
+ *
+ * Returns a negative error number on failure, or the number of bytes
+ * used / required on success.
+ */
+ssize_t v9fs_xattr_get(struct dentry *dentry, const char *name,
+		       void *buffer, size_t buffer_size)
+{
+	struct p9_fid *fid;
+
+	p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu\n",
+		 name, buffer_size);
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	return v9fs_fid_xattr_get(fid, name, buffer, buffer_size);
+}
+
+/*
+ * v9fs_xattr_set()
+ *
+ * Create, replace or remove an extended attribute for this inode. Buffer
+ * is NULL to remove an existing extended attribute, and non-NULL to
+ * either replace an existing extended attribute, or create a new extended
+ * attribute. The flags XATTR_REPLACE and XATTR_CREATE
+ * specify that an extended attribute must exist and must not exist
+ * previous to the call, respectively.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+int v9fs_xattr_set(struct dentry *dentry, const char *name,
+		   const void *value, size_t value_len, int flags)
+{
+	struct p9_fid *fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+	return v9fs_fid_xattr_set(fid, name, value, value_len, flags);
+}
+
+int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
+		   const void *value, size_t value_len, int flags)
+{
+	struct kvec kvec = {.iov_base = (void *)value, .iov_len = value_len};
+	struct iov_iter from;
+	int retval, err;
+
+	iov_iter_kvec(&from, WRITE | ITER_KVEC, &kvec, 1, value_len);
+
+	p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu flags = %d\n",
+		 name, value_len, flags);
+
+	/* Clone it */
+	fid = p9_client_walk(fid, 0, NULL, 1);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	/*
+	 * On success fid points to xattr
+	 */
+	retval = p9_client_xattrcreate(fid, name, value_len, flags);
+	if (retval < 0)
+		p9_debug(P9_DEBUG_VFS, "p9_client_xattrcreate failed %d\n",
+			 retval);
+	else
+		p9_client_write(fid, 0, &from, &retval);
+	err = p9_client_clunk(fid);
+	if (!retval && err)
+		retval = err;
+	return retval;
+}
+
+ssize_t v9fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
+{
+	return v9fs_xattr_get(dentry, NULL, buffer, buffer_size);
+}
+
+static int v9fs_xattr_handler_get(const struct xattr_handler *handler,
+				  struct dentry *dentry, const char *name,
+				  void *buffer, size_t size)
+{
+	const char *full_name = xattr_full_name(handler, name);
+
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+	return v9fs_xattr_get(dentry, full_name, buffer, size);
+}
+
+static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
+				  struct dentry *dentry, const char *name,
+				  const void *value, size_t size, int flags)
+{
+	const char *full_name = xattr_full_name(handler, name);
+
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+	return v9fs_xattr_set(dentry, full_name, value, size, flags);
+}
+
+static struct xattr_handler v9fs_xattr_user_handler = {
+	.prefix	= XATTR_USER_PREFIX,
+	.get	= v9fs_xattr_handler_get,
+	.set	= v9fs_xattr_handler_set,
+};
+
+static struct xattr_handler v9fs_xattr_trusted_handler = {
+	.prefix	= XATTR_TRUSTED_PREFIX,
+	.get	= v9fs_xattr_handler_get,
+	.set	= v9fs_xattr_handler_set,
+};
+
+#ifdef CONFIG_9P_FS_SECURITY
+static struct xattr_handler v9fs_xattr_security_handler = {
+	.prefix	= XATTR_SECURITY_PREFIX,
+	.get	= v9fs_xattr_handler_get,
+	.set	= v9fs_xattr_handler_set,
+};
+#endif
+
+const struct xattr_handler *v9fs_xattr_handlers[] = {
+	&v9fs_xattr_user_handler,
+	&v9fs_xattr_trusted_handler,
+#ifdef CONFIG_9P_FS_POSIX_ACL
+	&v9fs_xattr_acl_access_handler,
+	&v9fs_xattr_acl_default_handler,
+#endif
+#ifdef CONFIG_9P_FS_SECURITY
+	&v9fs_xattr_security_handler,
+#endif
+	NULL
+};

addons/9p/src/4.4.180/xattr.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright IBM Corporation, 2010
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+#ifndef FS_9P_XATTR_H
+#define FS_9P_XATTR_H
+
+#include <linux/xattr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+extern const struct xattr_handler *v9fs_xattr_handlers[];
+extern const struct xattr_handler v9fs_xattr_acl_access_handler;
+extern const struct xattr_handler v9fs_xattr_acl_default_handler;
+
+extern ssize_t v9fs_fid_xattr_get(struct p9_fid *, const char *,
+				  void *, size_t);
+extern ssize_t v9fs_xattr_get(struct dentry *, const char *,
+			      void *, size_t);
+extern int v9fs_fid_xattr_set(struct p9_fid *, const char *,
+			  const void *, size_t, int);
+extern int v9fs_xattr_set(struct dentry *, const char *,
+			  const void *, size_t, int);
+extern ssize_t v9fs_listxattr(struct dentry *, char *, size_t);
+#endif /* FS_9P_XATTR_H */