Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: (28 commits)
  net/9p: Return error on read with NULL buffer
  9p: Add datasync to client side TFSYNC/RFSYNC for dotl
  net/9p: Return error if we fail to encode protocol data
  fs/9p: Use generic_file_open with lookup_instantiate_filp
  fs/9p: Add missing iput in v9fs_vfs_lookup
  fs/9p: Use mknod 9p operation on create without open request
  net/9p: Add waitq to VirtIO transport.
  [net/9p]Serialize virtqueue operations to make VirtIO transport SMP safe.
  9p: Implement TREADLINK operation for 9p2000.L
  9p: Use V9FS_MAGIC in statfs
  9p: Implement TGETLOCK
  9p: Implement TLOCK
  [9p] Introduce client side TFSYNC/RFSYNC for dotl.
  [fs/9p] Add file_operations for cached mode in dotl protocol.
  fs/9p: Add access = client option to opt in acl evaluation.
  fs/9p: Implement create time inheritance
  fs/9p: Update ACL on chmod
  fs/9p: Implement setting posix acl
  fs/9p: Add xattr callbacks for POSIX ACL
  fs/9p: Implement POSIX ACL permission checking function
  ...

22 files changed, 1288 insertions, 150 deletions

diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt
index f9765e8cf086..b22abba78fed 100644
--- a/Documentation/filesystems/9p.txt
+++ b/Documentation/filesystems/9p.txt
@@ -111,7 +111,7 @@ OPTIONS
                 This can be used to share devices/named pipes/sockets between
                 hosts.  This functionality will be expanded in later versions.
 
-  access        there are three access modes.
+  access        there are four access modes.
                         user  = if a user tries to access a file on v9fs
                                 filesystem for the first time, v9fs sends an
                                 attach command (Tattach) for that user.
@@ -120,6 +120,8 @@ OPTIONS
                                 the files on the mounted filesystem
                         any   = v9fs does single attach and performs all
                                 operations as one user
+                        client = ACL based access check on the 9p client
+                                 side for access validation
 
   cachetag      cache tag to use the specified persistent cache.
                 cache tags for existing cache sessions can be listed at
diff --git a/fs/9p/Kconfig b/fs/9p/Kconfig
index 795233702a4e..7e0511476797 100644
--- a/fs/9p/Kconfig
+++ b/fs/9p/Kconfig
@@ -17,3 +17,16 @@ config 9P_FSCACHE
           Choose Y here to enable persistent, read-only local
           caching support for 9p clients using FS-Cache
 
+
+config 9P_FS_POSIX_ACL
+        bool "9P POSIX Access Control Lists"
+        depends on 9P_FS
+        select FS_POSIX_ACL
+        help
+          POSIX Access Control Lists (ACLs) support permissions for users and
+          groups beyond the owner/group/world scheme.
+
+          To learn more about Access Control Lists, visit the POSIX ACLs for
+          Linux website <http://acl.bestbits.at/>.
+
+          If you don't know what Access Control Lists are, say N
diff --git a/fs/9p/Makefile b/fs/9p/Makefile
index 91fba025fcbe..f8ba37effd1b 100644
--- a/fs/9p/Makefile
+++ b/fs/9p/Makefile
@@ -13,3 +13,4 @@ obj-$(CONFIG_9P_FS) := 9p.o
         xattr_user.o
 
 9p-$(CONFIG_9P_FSCACHE) += cache.o
+9p-$(CONFIG_9P_FS_POSIX_ACL) += acl.o
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
new file mode 100644
index 000000000000..12d602351dbe
--- /dev/null
+++ b/fs/9p/acl.c
@@ -0,0 +1,392 @@
+/*
+ * 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_vfs.h"
+#include "v9fs.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(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) {
+                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);
+                posix_acl_release(dacl);
+                posix_acl_release(pacl);
+        } else
+                retval = -EIO;
+
+        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;
+}
+
+int v9fs_check_acl(struct inode *inode, int mask)
+{
+        struct posix_acl *acl;
+        struct v9fs_session_info *v9ses;
+
+        v9ses = v9fs_inode2v9ses(inode);
+        if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) {
+                /*
+                 * On access = client mode get the acl
+                 * values from the server
+                 */
+                return 0;
+        }
+        acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
+
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
+        if (acl) {
+                int error = posix_acl_permission(inode, acl, mask);
+                posix_acl_release(acl);
+                return error;
+        }
+        return -EAGAIN;
+}
+
+static int v9fs_set_acl(struct dentry *dentry, int type, struct posix_acl *acl)
+{
+        int retval;
+        char *name;
+        size_t size;
+        void *buffer;
+        struct inode *inode = dentry->d_inode;
+
+        set_cached_acl(inode, type, acl);
+        /* 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(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_xattr_set(dentry, name, buffer, size, 0);
+err_free_out:
+        kfree(buffer);
+        return retval;
+}
+
+int v9fs_acl_chmod(struct dentry *dentry)
+{
+        int retval = 0;
+        struct posix_acl *acl, *clone;
+        struct inode *inode = dentry->d_inode;
+
+        if (S_ISLNK(inode->i_mode))
+                return -EOPNOTSUPP;
+        acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
+        if (acl) {
+                clone = posix_acl_clone(acl, GFP_KERNEL);
+                posix_acl_release(acl);
+                if (!clone)
+                        return -ENOMEM;
+                retval = posix_acl_chmod_masq(clone, inode->i_mode);
+                if (!retval)
+                        retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, clone);
+                posix_acl_release(clone);
+        }
+        return retval;
+}
+
+int v9fs_set_create_acl(struct dentry *dentry,
+                        struct posix_acl *dpacl, struct posix_acl *pacl)
+{
+        if (dpacl)
+                v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, dpacl);
+        if (pacl)
+                v9fs_set_acl(dentry, ACL_TYPE_ACCESS, pacl);
+        posix_acl_release(dpacl);
+        posix_acl_release(pacl);
+        return 0;
+}
+
+int v9fs_acl_mode(struct inode *dir, mode_t *modep,
+                  struct posix_acl **dpacl, struct posix_acl **pacl)
+{
+        int retval = 0;
+        mode_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) {
+                struct posix_acl *clone;
+
+                if (S_ISDIR(mode))
+                        *dpacl = acl;
+                clone = posix_acl_clone(acl, GFP_NOFS);
+                retval = -ENOMEM;
+                if (!clone)
+                        goto cleanup;
+
+                retval = posix_acl_create_masq(clone, &mode);
+                if (retval < 0) {
+                        posix_acl_release(clone);
+                        goto cleanup;
+                }
+                if (retval > 0)
+                        *pacl = clone;
+        }
+        *modep  = mode;
+        return 0;
+cleanup:
+        posix_acl_release(acl);
+        return retval;
+
+}
+
+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_inode2v9ses(dentry->d_inode);
+        /*
+         * 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(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_inode2v9ses(dentry->d_inode);
+        /*
+         * 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 (!is_owner_or_cap(inode))
+                return -EPERM;
+        if (value) {
+                /* update the cached acl value */
+                acl = posix_acl_from_xattr(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) {
+                        mode_t mode = inode->i_mode;
+                        retval = posix_acl_equiv_mode(acl, &mode);
+                        if (retval < 0)
+                                goto err_out;
+                        else {
+                                struct iattr iattr;
+                                if (retval == 0) {
+                                        /*
+                                         * ACL can be represented
+                                         * by the mode bits. So don't
+                                         * update ACL.
+                                         */
+                                        acl = NULL;
+                                        value = NULL;
+                                        size = 0;
+                                }
+                                /* Updte the mode bits */
+                                iattr.ia_mode = ((mode & S_IALLUGO) |
+                                                 (inode->i_mode & ~S_IALLUGO));
+                                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 = -EINVAL;
+                        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,
+};
diff --git a/fs/9p/acl.h b/fs/9p/acl.h
new file mode 100644
index 000000000000..59e18c2e8c7e
--- /dev/null
+++ b/fs/9p/acl.h
@@ -0,0 +1,49 @@
+/*
+ * 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 int v9fs_check_acl(struct inode *inode, int mask);
+extern int v9fs_acl_chmod(struct dentry *);
+extern int v9fs_set_create_acl(struct dentry *,
+                               struct posix_acl *, struct posix_acl *);
+extern int v9fs_acl_mode(struct inode *dir, mode_t *modep,
+                         struct posix_acl **dpacl, struct posix_acl **pacl);
+#else
+#define v9fs_check_acl NULL
+static inline int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
+{
+        return 0;
+}
+static inline int v9fs_acl_chmod(struct dentry *dentry)
+{
+        return 0;
+}
+static inline int v9fs_set_create_acl(struct dentry *dentry,
+                                      struct posix_acl *dpacl,
+                                      struct posix_acl *pacl)
+{
+        return 0;
+}
+static inline int v9fs_acl_mode(struct inode *dir, mode_t *modep,
+                                struct posix_acl **dpacl,
+                                struct posix_acl **pacl)
+{
+        return 0;
+}
+
+#endif
+#endif /* FS_9P_XATTR_H */
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 6406f896bf95..b00223c99d70 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -149,6 +149,7 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
         switch (access) {
         case V9FS_ACCESS_SINGLE:
         case V9FS_ACCESS_USER:
+        case V9FS_ACCESS_CLIENT:
                 uid = current_fsuid();
                 any = 0;
                 break;
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 38dc0e067599..2f77cd33ba83 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -193,7 +193,17 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
                                 v9ses->flags |= V9FS_ACCESS_USER;
                         else if (strcmp(s, "any") == 0)
                                 v9ses->flags |= V9FS_ACCESS_ANY;
-                        else {
+                        else if (strcmp(s, "client") == 0) {
+#ifdef CONFIG_9P_FS_POSIX_ACL
+                                v9ses->flags |= V9FS_ACCESS_CLIENT;
+#else
+                                P9_DPRINTK(P9_DEBUG_ERROR,
+                                        "access=client option not supported\n");
+                                kfree(s);
+                                ret = -EINVAL;
+                                goto free_and_return;
+#endif
+                        } else {
                                 v9ses->flags |= V9FS_ACCESS_SINGLE;
                                 v9ses->uid = simple_strtoul(s, &e, 10);
                                 if (*e != '\0')
@@ -278,6 +288,16 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 
         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)) {
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 4c963c9fc41f..cb6396855e2d 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -33,13 +33,17 @@
  *
  * 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
+
 enum p9_session_flags {
         V9FS_PROTO_2000U        = 0x01,
         V9FS_PROTO_2000L        = 0x02,
         V9FS_ACCESS_SINGLE      = 0x04,
         V9FS_ACCESS_USER        = 0x08,
-        V9FS_ACCESS_ANY         = 0x0C,
-        V9FS_ACCESS_MASK        = 0x0C,
+        V9FS_ACCESS_CLIENT      = 0x10
 };
 
 /* possible values of ->cache */
@@ -113,8 +117,6 @@ void v9fs_session_close(struct v9fs_session_info *v9ses);
 void v9fs_session_cancel(struct v9fs_session_info *v9ses);
 void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
 
-#define V9FS_MAGIC 0x01021997
-
 /* other default globals */
 #define V9FS_PORT       564
 #define V9FS_DEFUSER    "nobody"
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index 88418c419ea7..bab0eac873f4 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -64,3 +64,7 @@ int v9fs_uflags2omode(int uflags, int extended);
 
 ssize_t v9fs_file_readn(struct file *, 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, int datasync);
+
+#define P9_LOCK_TIMEOUT (30*HZ)
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 90e38449f4b3..b7f2a8e3863e 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -154,10 +154,40 @@ static int v9fs_launder_page(struct page *page)
         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.
+ *
+ */
+ssize_t v9fs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
+                loff_t pos, unsigned long nr_segs)
+{
+        P9_DPRINTK(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;
+}
 const struct address_space_operations v9fs_addr_operations = {
       .readpage = v9fs_vfs_readpage,
       .readpages = v9fs_vfs_readpages,
       .releasepage = v9fs_release_page,
       .invalidatepage = v9fs_invalidate_page,
       .launder_page = v9fs_launder_page,
+      .direct_IO = v9fs_direct_IO,
 };
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 899f168fd19c..b84ebe8cefed 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -242,7 +242,8 @@ static int v9fs_dir_readdir_dotl(struct file *filp, void *dirent,
                 while (rdir->head < rdir->tail) {
 
                         err = p9dirent_read(rdir->buf + rdir->head,
-                                                buflen - rdir->head, &curdirent,
+                                                rdir->tail - rdir->head,
+                                                &curdirent,
                                                 fid->clnt->proto_version);
                         if (err < 0) {
                                 P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
@@ -314,4 +315,5 @@ const struct file_operations v9fs_dir_operations_dotl = {
         .readdir = v9fs_dir_readdir_dotl,
         .open = v9fs_file_open,
         .release = v9fs_dir_release,
+        .fsync = v9fs_file_fsync_dotl,
 };
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index e97c92bd6f16..240c30674396 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -33,6 +33,7 @@
 #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>
@@ -44,6 +45,7 @@
 #include "cache.h"
 
 static const struct file_operations v9fs_cached_file_operations;
+static const struct file_operations v9fs_cached_file_operations_dotl;
 
 /**
  * v9fs_file_open - open a file (or directory)
@@ -92,6 +94,8 @@ int v9fs_file_open(struct inode *inode, struct file *file)
                 /* enable cached file options */
                 if(file->f_op == &v9fs_file_operations)
                         file->f_op = &v9fs_cached_file_operations;
+                else if (file->f_op == &v9fs_file_operations_dotl)
+                        file->f_op = &v9fs_cached_file_operations_dotl;
 
 #ifdef CONFIG_9P_FSCACHE
                 v9fs_cache_inode_set_cookie(inode, file);
@@ -130,6 +134,206 @@ static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
         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));
+        flock.type = fl->fl_type;
+        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;
+                schedule_timeout_interruptible(P9_LOCK_TIMEOUT);
+        }
+
+        /* 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 = fl->fl_type;
+        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;
+        if (glock.type != F_UNLCK) {
+                fl->fl_type = glock.type;
+                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;
+        } else
+                fl->fl_type = F_UNLCK;
+
+        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 = filp->f_path.dentry->d_inode;
+        int ret = -ENOLCK;
+
+        P9_DPRINTK(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 = filp->f_path.dentry->d_inode;
+        int ret = -ENOLCK;
+
+        P9_DPRINTK(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_file_readn - read from a file
  * @filp: file pointer to read
@@ -219,7 +423,9 @@ static ssize_t
 v9fs_file_write(struct file *filp, const char __user * data,
                 size_t count, loff_t * offset)
 {
-        int n, rsize, total = 0;
+        ssize_t retval;
+        size_t total = 0;
+        int n;
         struct p9_fid *fid;
         struct p9_client *clnt;
         struct inode *inode = filp->f_path.dentry->d_inode;
@@ -232,14 +438,19 @@ v9fs_file_write(struct file *filp, const char __user * data,
         fid = filp->private_data;
         clnt = fid->clnt;
 
-        rsize = fid->iounit ? fid->iounit : clnt->msize - P9_IOHDRSZ;
+        retval = generic_write_checks(filp, &origin, &count, 0);
+        if (retval)
+                goto out;
 
-        do {
-                if (count < rsize)
-                        rsize = count;
+        retval = -EINVAL;
+        if ((ssize_t) count < 0)
+                goto out;
+        retval = 0;
+        if (!count)
+                goto out;
 
-                n = p9_client_write(fid, NULL, data+total, origin+total,
-                                                                        rsize);
+        do {
+                n = p9_client_write(fid, NULL, data+total, origin+total, count);
                 if (n <= 0)
                         break;
                 count -= n;
@@ -258,9 +469,11 @@ v9fs_file_write(struct file *filp, const char __user * data,
         }
 
         if (n < 0)
-                return n;
-
-        return total;
+                retval = n;
+        else
+                retval = total;
+out:
+        return retval;
 }
 
 static int v9fs_file_fsync(struct file *filp, int datasync)
@@ -278,6 +491,20 @@ static int v9fs_file_fsync(struct file *filp, int datasync)
         return retval;
 }
 
+int v9fs_file_fsync_dotl(struct file *filp, int datasync)
+{
+        struct p9_fid *fid;
+        int retval;
+
+        P9_DPRINTK(P9_DEBUG_VFS, "v9fs_file_fsync_dotl: filp %p datasync %x\n",
+                        filp, datasync);
+
+        fid = filp->private_data;
+
+        retval = p9_client_fsync(fid, datasync);
+        return retval;
+}
+
 static const struct file_operations v9fs_cached_file_operations = {
         .llseek = generic_file_llseek,
         .read = do_sync_read,
@@ -290,6 +517,19 @@ static const struct file_operations v9fs_cached_file_operations = {
         .fsync = v9fs_file_fsync,
 };
 
+static const struct file_operations v9fs_cached_file_operations_dotl = {
+        .llseek = generic_file_llseek,
+        .read = do_sync_read,
+        .aio_read = generic_file_aio_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,
+};
+
 const struct file_operations v9fs_file_operations = {
         .llseek = generic_file_llseek,
         .read = v9fs_file_read,
@@ -307,7 +547,8 @@ const struct file_operations v9fs_file_operations_dotl = {
         .write = v9fs_file_write,
         .open = v9fs_file_open,
         .release = v9fs_dir_release,
-        .lock = v9fs_file_lock,
+        .lock = v9fs_file_lock_dotl,
+        .flock = v9fs_file_flock_dotl,
         .mmap = generic_file_readonly_mmap,
-        .fsync = v9fs_file_fsync,
+        .fsync = v9fs_file_fsync_dotl,
 };
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index ef5905f7c8a3..34bf71b56542 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -36,6 +36,7 @@
 #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>
 
@@ -44,6 +45,7 @@
 #include "fid.h"
 #include "cache.h"
 #include "xattr.h"
+#include "acl.h"
 
 static const struct inode_operations v9fs_dir_inode_operations;
 static const struct inode_operations v9fs_dir_inode_operations_dotu;
@@ -53,6 +55,10 @@ static const struct inode_operations v9fs_file_inode_operations_dotl;
 static const struct inode_operations v9fs_symlink_inode_operations;
 static const struct inode_operations v9fs_symlink_inode_operations_dotl;
 
+static int
+v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
+                    dev_t rdev);
+
 /**
  * unixmode2p9mode - convert unix mode bits to plan 9
  * @v9ses: v9fs session information
@@ -500,6 +506,11 @@ v9fs_inode_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
         v9fs_vcookie_set_qid(ret, &st->qid);
         v9fs_cache_inode_get_cookie(ret);
 #endif
+        err = v9fs_get_acl(ret, fid);
+        if (err) {
+                iput(ret);
+                goto error;
+        }
         kfree(st);
         return ret;
 error:
@@ -553,13 +564,6 @@ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
         return retval;
 }
 
-static int
-v9fs_open_created(struct inode *inode, struct file *file)
-{
-        return 0;
-}
-
-
 /**
  * v9fs_create - Create a file
  * @v9ses: session information
@@ -655,29 +659,37 @@ error:
  */
 
 static int
-v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int mode,
+v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
                 struct nameidata *nd)
 {
         int err = 0;
         char *name = NULL;
         gid_t gid;
         int flags;
+        mode_t mode;
         struct v9fs_session_info *v9ses;
         struct p9_fid *fid = NULL;
         struct p9_fid *dfid, *ofid;
         struct file *filp;
         struct p9_qid qid;
         struct inode *inode;
+        struct posix_acl *pacl = NULL, *dacl = NULL;
 
         v9ses = v9fs_inode2v9ses(dir);
         if (nd && nd->flags & LOOKUP_OPEN)
                 flags = nd->intent.open.flags - 1;
-        else
-                flags = O_RDWR;
+        else {
+                /*
+                 * create call without LOOKUP_OPEN is due
+                 * to mknod of regular files. So use mknod
+                 * operation.
+                 */
+                return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
+        }
 
         name = (char *) dentry->d_name.name;
         P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
-                        "mode:0x%x\n", name, flags, mode);
+                        "mode:0x%x\n", name, flags, omode);
 
         dfid = v9fs_fid_lookup(dentry->d_parent);
         if (IS_ERR(dfid)) {
@@ -695,6 +707,15 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int mode,
         }
 
         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_DPRINTK(P9_DEBUG_VFS,
+                           "Failed to get acl values in creat %d\n", err);
+                goto error;
+        }
         err = p9_client_create_dotl(ofid, name, flags, mode, gid, &qid);
         if (err < 0) {
                 P9_DPRINTK(P9_DEBUG_VFS,
@@ -702,46 +723,52 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int mode,
                                 err);
                 goto error;
         }
+        /* instantiate inode and assign the unopened fid to the dentry */
+        if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE ||
+            (nd && nd->flags & LOOKUP_OPEN)) {
+                fid = p9_client_walk(dfid, 1, &name, 1);
+                if (IS_ERR(fid)) {
+                        err = PTR_ERR(fid);
+                        P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
+                                err);
+                        fid = NULL;
+                        goto error;
+                }
 
-        /* No need to populate the inode if we are not opening the file AND
-         * not in cached mode.
-         */
-        if (!v9ses->cache && !(nd && nd->flags & LOOKUP_OPEN)) {
-                /* Not in cached mode. No need to populate inode with stat */
-                dentry->d_op = &v9fs_dentry_operations;
-                p9_client_clunk(ofid);
-                d_instantiate(dentry, NULL);
-                return 0;
-        }
-
-        /* 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_DPRINTK(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_inode_from_fid(v9ses, fid, dir->i_sb);
-        if (IS_ERR(inode)) {
-                err = PTR_ERR(inode);
-                P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
-                goto error;
-        }
-        if (v9ses->cache)
+                inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
+                if (IS_ERR(inode)) {
+                        err = PTR_ERR(inode);
+                        P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n",
+                                err);
+                        goto error;
+                }
                 dentry->d_op = &v9fs_cached_dentry_operations;
-        else
+                d_instantiate(dentry, inode);
+                err = v9fs_fid_add(dentry, fid);
+                if (err < 0)
+                        goto error;
+                /* The fid would get clunked via a dput */
+                fid = NULL;
+        } 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);
+                if (IS_ERR(inode)) {
+                        err = PTR_ERR(inode);
+                        goto error;
+                }
                 dentry->d_op = &v9fs_dentry_operations;
-        d_instantiate(dentry, inode);
-        err = v9fs_fid_add(dentry, fid);
-        if (err < 0)
-                goto error;
+                d_instantiate(dentry, inode);
+        }
+        /* Now set the ACL based on the default value */
+        v9fs_set_create_acl(dentry, dacl, pacl);
 
         /* if we are opening a file, assign the open fid to the file */
         if (nd && nd->flags & LOOKUP_OPEN) {
-                filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
+                filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
                 if (IS_ERR(filp)) {
                         p9_client_clunk(ofid);
                         return PTR_ERR(filp);
@@ -800,7 +827,7 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 
         /* if we are opening a file, assign the open fid to the file */
         if (nd && nd->flags & LOOKUP_OPEN) {
-                filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
+                filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
                 if (IS_ERR(filp)) {
                         err = PTR_ERR(filp);
                         goto error;
@@ -859,23 +886,28 @@ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
  *
  */
 
-static int v9fs_vfs_mkdir_dotl(struct inode *dir, struct dentry *dentry,
-                                        int mode)
+static int v9fs_vfs_mkdir_dotl(struct inode *dir,
+                               struct dentry *dentry, int omode)
 {
         int err;
         struct v9fs_session_info *v9ses;
         struct p9_fid *fid = NULL, *dfid = NULL;
         gid_t gid;
         char *name;
+        mode_t mode;
         struct inode *inode;
         struct p9_qid qid;
         struct dentry *dir_dentry;
+        struct posix_acl *dacl = NULL, *pacl = NULL;
 
         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
         err = 0;
         v9ses = v9fs_inode2v9ses(dir);
 
-        mode |= S_IFDIR;
+        omode |= S_IFDIR;
+        if (dir->i_mode & S_ISGID)
+                omode |= S_ISGID;
+
         dir_dentry = v9fs_dentry_from_dir_inode(dir);
         dfid = v9fs_fid_lookup(dir_dentry);
         if (IS_ERR(dfid)) {
@@ -886,11 +918,14 @@ static int v9fs_vfs_mkdir_dotl(struct inode *dir, struct dentry *dentry,
         }
 
         gid = v9fs_get_fsgid_for_create(dir);
-        if (gid < 0) {
-                P9_DPRINTK(P9_DEBUG_VFS, "v9fs_get_fsgid_for_create failed\n");
+        mode = omode;
+        /* Update mode based on ACL value */
+        err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
+        if (err) {
+                P9_DPRINTK(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)
@@ -920,7 +955,23 @@ static int v9fs_vfs_mkdir_dotl(struct inode *dir, struct dentry *dentry,
                 if (err < 0)
                         goto error;
                 fid = NULL;
+        } 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);
+                if (IS_ERR(inode)) {
+                        err = PTR_ERR(inode);
+                        goto error;
+                }
+                dentry->d_op = &v9fs_dentry_operations;
+                d_instantiate(dentry, inode);
         }
+        /* Now set the ACL based on the default value */
+        v9fs_set_create_acl(dentry, dacl, pacl);
+
 error:
         if (fid)
                 p9_client_clunk(fid);
@@ -979,7 +1030,7 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 
         result = v9fs_fid_add(dentry, fid);
         if (result < 0)
-                goto error;
+                goto error_iput;
 
 inst_out:
         if (v9ses->cache)
@@ -990,6 +1041,8 @@ inst_out:
         d_add(dentry, inode);
         return NULL;
 
+error_iput:
+        iput(inode);
 error:
         p9_client_clunk(fid);
 
@@ -1237,7 +1290,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
  *
  */
 
-static int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
+int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 {
         int retval;
         struct v9fs_session_info *v9ses;
@@ -1279,6 +1332,12 @@ static int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 
         setattr_copy(dentry->d_inode, iattr);
         mark_inode_dirty(dentry->d_inode);
+        if (iattr->ia_valid & ATTR_MODE) {
+                /* We also want to update ACL when we update mode bits */
+                retval = v9fs_acl_chmod(dentry);
+                if (retval < 0)
+                        return retval;
+        }
         return 0;
 }
 
@@ -1473,7 +1532,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
         if (IS_ERR(fid))
                 return PTR_ERR(fid);
 
-        if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses))
+        if (!v9fs_proto_dotu(v9ses))
                 return -EBADF;
 
         st = p9_client_stat(fid);
@@ -1616,11 +1675,6 @@ v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
 
         gid = v9fs_get_fsgid_for_create(dir);
 
-        if (gid < 0) {
-                P9_DPRINTK(P9_DEBUG_VFS, "v9fs_get_egid failed %d\n", gid);
-                goto error;
-        }
-
         /* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
         err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
 
@@ -1855,21 +1909,23 @@ v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
  *
  */
 static int
-v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int mode,
+v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
                 dev_t rdev)
 {
         int err;
         char *name;
+        mode_t mode;
         struct v9fs_session_info *v9ses;
         struct p9_fid *fid = NULL, *dfid = NULL;
         struct inode *inode;
         gid_t gid;
         struct p9_qid qid;
         struct dentry *dir_dentry;
+        struct posix_acl *dacl = NULL, *pacl = NULL;
 
         P9_DPRINTK(P9_DEBUG_VFS,
                 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
-                dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
+                dentry->d_name.name, omode, MAJOR(rdev), MINOR(rdev));
 
         if (!new_valid_dev(rdev))
                 return -EINVAL;
@@ -1885,11 +1941,14 @@ v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int mode,
         }
 
         gid = v9fs_get_fsgid_for_create(dir);
-        if (gid < 0) {
-                P9_DPRINTK(P9_DEBUG_VFS, "v9fs_get_fsgid_for_create failed\n");
+        mode = omode;
+        /* Update mode based on ACL value */
+        err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
+        if (err) {
+                P9_DPRINTK(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);
@@ -1933,13 +1992,68 @@ v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int mode,
                 dentry->d_op = &v9fs_dentry_operations;
                 d_instantiate(dentry, inode);
         }
-
+        /* Now set the ACL based on the default value */
+        v9fs_set_create_acl(dentry, dacl, pacl);
 error:
         if (fid)
                 p9_client_clunk(fid);
         return err;
 }
 
+static int
+v9fs_vfs_readlink_dotl(struct dentry *dentry, char *buffer, int buflen)
+{
+        int retval;
+        struct p9_fid *fid;
+        char *target = NULL;
+
+        P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
+        retval = -EPERM;
+        fid = v9fs_fid_lookup(dentry);
+        if (IS_ERR(fid))
+                return PTR_ERR(fid);
+
+        retval = p9_client_readlink(fid, &target);
+        if (retval < 0)
+                return retval;
+
+        strncpy(buffer, target, buflen);
+        P9_DPRINTK(P9_DEBUG_VFS, "%s -> %s\n", dentry->d_name.name, buffer);
+
+        retval = strnlen(buffer, buflen);
+        return retval;
+}
+
+/**
+ * v9fs_vfs_follow_link_dotl - follow a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ *
+ */
+
+static void *
+v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
+{
+        int len = 0;
+        char *link = __getname();
+
+        P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
+
+        if (!link)
+                link = ERR_PTR(-ENOMEM);
+        else {
+                len = v9fs_vfs_readlink_dotl(dentry, link, PATH_MAX);
+                if (len < 0) {
+                        __putname(link);
+                        link = ERR_PTR(len);
+                } else
+                        link[min(len, PATH_MAX-1)] = 0;
+        }
+        nd_set_link(nd, link);
+
+        return NULL;
+}
+
 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
         .create = v9fs_vfs_create,
         .lookup = v9fs_vfs_lookup,
@@ -1970,7 +2084,7 @@ static const struct inode_operations v9fs_dir_inode_operations_dotl = {
         .getxattr = generic_getxattr,
         .removexattr = generic_removexattr,
         .listxattr = v9fs_listxattr,
-
+        .check_acl = v9fs_check_acl,
 };
 
 static const struct inode_operations v9fs_dir_inode_operations = {
@@ -1997,6 +2111,7 @@ static const struct inode_operations v9fs_file_inode_operations_dotl = {
         .getxattr = generic_getxattr,
         .removexattr = generic_removexattr,
         .listxattr = v9fs_listxattr,
+        .check_acl = v9fs_check_acl,
 };
 
 static const struct inode_operations v9fs_symlink_inode_operations = {
@@ -2008,8 +2123,8 @@ static const struct inode_operations v9fs_symlink_inode_operations = {
 };
 
 static const struct inode_operations v9fs_symlink_inode_operations_dotl = {
-        .readlink = generic_readlink,
-        .follow_link = v9fs_vfs_follow_link,
+        .readlink = v9fs_vfs_readlink_dotl,
+        .follow_link = v9fs_vfs_follow_link_dotl,
         .put_link = v9fs_vfs_put_link,
         .getattr = v9fs_vfs_getattr_dotl,
         .setattr = v9fs_vfs_setattr_dotl,
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index 1d12ba0ed3db..48d4215c60a8 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -39,6 +39,7 @@
 #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>
 
@@ -46,6 +47,7 @@
 #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;
 
@@ -88,6 +90,11 @@ v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
         sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
             MS_NOATIME;
 
+#ifdef CONFIG_9P_FS_POSIX_ACL
+        if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)
+                sb->s_flags |= MS_POSIXACL;
+#endif
+
         save_mount_options(sb, data);
 }
 
@@ -149,7 +156,6 @@ static int v9fs_get_sb(struct file_system_type *fs_type, int flags,
                 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);
@@ -174,7 +180,9 @@ static int v9fs_get_sb(struct file_system_type *fs_type, int flags,
                 p9stat_free(st);
                 kfree(st);
         }
-
+        retval = v9fs_get_acl(inode, fid);
+        if (retval)
+                goto release_sb;
         v9fs_fid_add(root, fid);
 
         P9_DPRINTK(P9_DEBUG_VFS, " simple set mount, return 0\n");
@@ -249,7 +257,7 @@ static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
         if (v9fs_proto_dotl(v9ses)) {
                 res = p9_client_statfs(fid, &rs);
                 if (res == 0) {
-                        buf->f_type = rs.type;
+                        buf->f_type = V9FS_MAGIC;
                         buf->f_bsize = rs.bsize;
                         buf->f_blocks = rs.blocks;
                         buf->f_bfree = rs.bfree;
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index f88e5c2dc873..43ec7df84336 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -21,30 +21,13 @@
 #include "fid.h"
 #include "xattr.h"
 
-/*
- * 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)
+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 *fid, *attr_fid;
-
-        P9_DPRINTK(P9_DEBUG_VFS, "%s: name = %s value_len = %zu\n",
-                __func__, name, buffer_size);
-
-        fid = v9fs_fid_lookup(dentry);
-        if (IS_ERR(fid))
-                return PTR_ERR(fid);
+        struct p9_fid *attr_fid;
 
         attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
         if (IS_ERR(attr_fid)) {
@@ -88,6 +71,31 @@ error:
 
 }
 
+
+/*
+ * 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_DPRINTK(P9_DEBUG_VFS, "%s: name = %s value_len = %zu\n",
+                __func__, 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()
  *
@@ -156,5 +164,9 @@ ssize_t v9fs_listxattr(struct dentry *dentry, char *buffer, size_t 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
 };
diff --git a/fs/9p/xattr.h b/fs/9p/xattr.h
index 9ddf672ae5c4..eaa837c53bd5 100644
--- a/fs/9p/xattr.h
+++ b/fs/9p/xattr.h
@@ -15,10 +15,16 @@
 #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_xattr_set(struct dentry *, const char *,
diff --git a/include/linux/magic.h b/include/linux/magic.h
index eb9800f05782..ff690d05f129 100644
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -57,5 +57,6 @@
 
 #define DEVPTS_SUPER_MAGIC      0x1cd1
 #define SOCKFS_MAGIC            0x534F434B
+#define V9FS_MAGIC              0x01021997
 
 #endif /* __LINUX_MAGIC_H__ */
diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h
index a8de812ccbc8..071fd7a8d781 100644
--- a/include/net/9p/9p.h
+++ b/include/net/9p/9p.h
@@ -86,6 +86,8 @@ do { \
 
 /**
  * enum p9_msg_t - 9P message types
+ * @P9_TLERROR: not used
+ * @P9_RLERROR: response for any failed request for 9P2000.L
  * @P9_TSTATFS: file system status request
  * @P9_RSTATFS: file system status response
  * @P9_TSYMLINK: make symlink request
@@ -137,6 +139,8 @@ do { \
  */
 
 enum p9_msg_t {
+        P9_TLERROR = 6,
+        P9_RLERROR,
         P9_TSTATFS = 8,
         P9_RSTATFS,
         P9_TLOPEN = 12,
@@ -149,6 +153,8 @@ enum p9_msg_t {
         P9_RMKNOD,
         P9_TRENAME = 20,
         P9_RRENAME,
+        P9_TREADLINK = 22,
+        P9_RREADLINK,
         P9_TGETATTR = 24,
         P9_RGETATTR,
         P9_TSETATTR = 26,
@@ -159,6 +165,12 @@ enum p9_msg_t {
         P9_RXATTRCREATE,
         P9_TREADDIR = 40,
         P9_RREADDIR,
+        P9_TFSYNC = 50,
+        P9_RFSYNC,
+        P9_TLOCK = 52,
+        P9_RLOCK,
+        P9_TGETLOCK = 54,
+        P9_RGETLOCK,
         P9_TLINK = 70,
         P9_RLINK,
         P9_TMKDIR = 72,
@@ -458,6 +470,48 @@ struct p9_iattr_dotl {
         u64 mtime_nsec;
 };
 
+#define P9_LOCK_SUCCESS 0
+#define P9_LOCK_BLOCKED 1
+#define P9_LOCK_ERROR 2
+#define P9_LOCK_GRACE 3
+
+#define P9_LOCK_FLAGS_BLOCK 1
+#define P9_LOCK_FLAGS_RECLAIM 2
+
+/* struct p9_flock: POSIX lock structure
+ * @type - type of lock
+ * @flags - lock flags
+ * @start - starting offset of the lock
+ * @length - number of bytes
+ * @proc_id - process id which wants to take lock
+ * @client_id - client id
+ */
+
+struct p9_flock {
+        u8 type;
+        u32 flags;
+        u64 start;
+        u64 length;
+        u32 proc_id;
+        char *client_id;
+};
+
+/* struct p9_getlock: getlock structure
+ * @type - type of lock
+ * @start - starting offset of the lock
+ * @length - number of bytes
+ * @proc_id - process id which wants to take lock
+ * @client_id - client id
+ */
+
+struct p9_getlock {
+        u8 type;
+        u64 start;
+        u64 length;
+        u32 proc_id;
+        char *client_id;
+};
+
 /* Structures for Protocol Operations */
 struct p9_tstatfs {
         u32 fid;
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index 7f63d5ab7b44..83ba6a4d58a3 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -229,6 +229,7 @@ int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, gid_t gid,
 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
                 gid_t gid, struct p9_qid *qid);
 int p9_client_clunk(struct p9_fid *fid);
+int p9_client_fsync(struct p9_fid *fid, int datasync);
 int p9_client_remove(struct p9_fid *fid);
 int p9_client_read(struct p9_fid *fid, char *data, char __user *udata,
                                                         u64 offset, u32 count);
@@ -248,6 +249,8 @@ int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode,
                         dev_t rdev, gid_t gid, struct p9_qid *);
 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
                                 gid_t gid, struct p9_qid *);
+int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
+int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
 struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
 void p9_client_cb(struct p9_client *c, struct p9_req_t *req);
 
@@ -259,5 +262,6 @@ int p9_is_proto_dotu(struct p9_client *clnt);
 int p9_is_proto_dotl(struct p9_client *clnt);
 struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
 int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
+int p9_client_readlink(struct p9_fid *fid, char **target);
 
 #endif /* NET_9P_CLIENT_H */
diff --git a/net/9p/client.c b/net/9p/client.c
index 83bf0541d66f..a848bca9fbff 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -450,32 +450,43 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
                 return err;
         }
 
-        if (type == P9_RERROR) {
+        if (type == P9_RERROR || type == P9_RLERROR) {
                 int ecode;
-                char *ename;
 
-                err = p9pdu_readf(req->rc, c->proto_version, "s?d",
-                                                        &ename, &ecode);
-                if (err) {
-                        P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
-                                                                        err);
-                        return err;
-                }
+                if (!p9_is_proto_dotl(c)) {
+                        char *ename;
 
-                if (p9_is_proto_dotu(c) ||
-                        p9_is_proto_dotl(c))
-                        err = -ecode;
+                        err = p9pdu_readf(req->rc, c->proto_version, "s?d",
+                                                                &ename, &ecode);
+                        if (err)
+                                goto out_err;
+
+                        if (p9_is_proto_dotu(c))
+                                err = -ecode;
+
+                        if (!err || !IS_ERR_VALUE(err)) {
+                                err = p9_errstr2errno(ename, strlen(ename));
+
+                                P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
 
-                if (!err || !IS_ERR_VALUE(err))
-                        err = p9_errstr2errno(ename, strlen(ename));
+                                kfree(ename);
+                        }
+                } else {
+                        err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
+                        err = -ecode;
 
-                P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
+                        P9_DPRINTK(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
+                }
 
-                kfree(ename);
         } else
                 err = 0;
 
         return err;
+
+out_err:
+        P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
+
+        return err;
 }
 
 /**
@@ -568,11 +579,14 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
         va_start(ap, fmt);
         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
         va_end(ap);
+        if (err)
+                goto reterr;
         p9pdu_finalize(req->tc);
 
         err = c->trans_mod->request(c, req);
         if (err < 0) {
-                c->status = Disconnected;
+                if (err != -ERESTARTSYS)
+                        c->status = Disconnected;
                 goto reterr;
         }
 
@@ -1151,12 +1165,44 @@ int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
 }
 EXPORT_SYMBOL(p9_client_link);
 
+int p9_client_fsync(struct p9_fid *fid, int datasync)
+{
+        int err;
+        struct p9_client *clnt;
+        struct p9_req_t *req;
+
+        P9_DPRINTK(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
+                        fid->fid, datasync);
+        err = 0;
+        clnt = fid->clnt;
+
+        req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
+        if (IS_ERR(req)) {
+                err = PTR_ERR(req);
+                goto error;
+        }
+
+        P9_DPRINTK(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
+
+        p9_free_req(clnt, req);
+
+error:
+        return err;
+}
+EXPORT_SYMBOL(p9_client_fsync);
+
 int p9_client_clunk(struct p9_fid *fid)
 {
         int err;
         struct p9_client *clnt;
         struct p9_req_t *req;
 
+        if (!fid) {
+                P9_EPRINTK(KERN_WARNING, "Trying to clunk with NULL fid\n");
+                dump_stack();
+                return 0;
+        }
+
         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
         err = 0;
         clnt = fid->clnt;
@@ -1240,16 +1286,13 @@ p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
 
         if (data) {
                 memmove(data, dataptr, count);
-        }
-
-        if (udata) {
+        } else {
                 err = copy_to_user(udata, dataptr, count);
                 if (err) {
                         err = -EFAULT;
                         goto free_and_error;
                 }
         }
-
         p9_free_req(clnt, req);
         return count;
 
@@ -1761,3 +1804,96 @@ error:
 
 }
 EXPORT_SYMBOL(p9_client_mkdir_dotl);
+
+int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
+{
+        int err;
+        struct p9_client *clnt;
+        struct p9_req_t *req;
+
+        err = 0;
+        clnt = fid->clnt;
+        P9_DPRINTK(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
+                        "start %lld length %lld proc_id %d client_id %s\n",
+                        fid->fid, flock->type, flock->flags, flock->start,
+                        flock->length, flock->proc_id, flock->client_id);
+
+        req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
+                                flock->flags, flock->start, flock->length,
+                                        flock->proc_id, flock->client_id);
+
+        if (IS_ERR(req))
+                return PTR_ERR(req);
+
+        err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
+        if (err) {
+                p9pdu_dump(1, req->rc);
+                goto error;
+        }
+        P9_DPRINTK(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
+error:
+        p9_free_req(clnt, req);
+        return err;
+
+}
+EXPORT_SYMBOL(p9_client_lock_dotl);
+
+int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
+{
+        int err;
+        struct p9_client *clnt;
+        struct p9_req_t *req;
+
+        err = 0;
+        clnt = fid->clnt;
+        P9_DPRINTK(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
+                "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
+                glock->start, glock->length, glock->proc_id, glock->client_id);
+
+        req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
+                glock->start, glock->length, glock->proc_id, glock->client_id);
+
+        if (IS_ERR(req))
+                return PTR_ERR(req);
+
+        err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
+                        &glock->start, &glock->length, &glock->proc_id,
+                        &glock->client_id);
+        if (err) {
+                p9pdu_dump(1, req->rc);
+                goto error;
+        }
+        P9_DPRINTK(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
+                "proc_id %d client_id %s\n", glock->type, glock->start,
+                glock->length, glock->proc_id, glock->client_id);
+error:
+        p9_free_req(clnt, req);
+        return err;
+}
+EXPORT_SYMBOL(p9_client_getlock_dotl);
+
+int p9_client_readlink(struct p9_fid *fid, char **target)
+{
+        int err;
+        struct p9_client *clnt;
+        struct p9_req_t *req;
+
+        err = 0;
+        clnt = fid->clnt;
+        P9_DPRINTK(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
+
+        req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
+        if (IS_ERR(req))
+                return PTR_ERR(req);
+
+        err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
+        if (err) {
+                p9pdu_dump(1, req->rc);
+                goto error;
+        }
+        P9_DPRINTK(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
+error:
+        p9_free_req(clnt, req);
+        return err;
+}
+EXPORT_SYMBOL(p9_client_readlink);
diff --git a/net/9p/protocol.c b/net/9p/protocol.c
index 3acd3afb20c8..45c15f491401 100644
--- a/net/9p/protocol.c
+++ b/net/9p/protocol.c
@@ -122,9 +122,8 @@ 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);
-        int err = copy_from_user(&pdu->sdata[pdu->size], udata, len);
-        if (err)
-                printk(KERN_WARNING "pdu_write_u returning: %d\n", err);
+        if (copy_from_user(&pdu->sdata[pdu->size], udata, len))
+                len = 0;
 
         pdu->size += len;
         return size - len;
diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index b88515936e4b..c8f3f72ab20e 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -75,6 +75,8 @@ struct virtio_chan {
         struct p9_client *client;
         struct virtio_device *vdev;
         struct virtqueue *vq;
+        int ring_bufs_avail;
+        wait_queue_head_t *vc_wq;
 
         /* Scatterlist: can be too big for stack. */
         struct scatterlist sg[VIRTQUEUE_NUM];
@@ -134,16 +136,30 @@ static void req_done(struct virtqueue *vq)
         struct p9_fcall *rc;
         unsigned int len;
         struct p9_req_t *req;
+        unsigned long flags;
 
         P9_DPRINTK(P9_DEBUG_TRANS, ": request done\n");
 
-        while ((rc = virtqueue_get_buf(chan->vq, &len)) != NULL) {
-                P9_DPRINTK(P9_DEBUG_TRANS, ": rc %p\n", rc);
-                P9_DPRINTK(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);
-        }
+        do {
+                spin_lock_irqsave(&chan->lock, flags);
+                rc = virtqueue_get_buf(chan->vq, &len);
+
+                if (rc != NULL) {
+                        if (!chan->ring_bufs_avail) {
+                                chan->ring_bufs_avail = 1;
+                                wake_up(chan->vc_wq);
+                        }
+                        spin_unlock_irqrestore(&chan->lock, flags);
+                        P9_DPRINTK(P9_DEBUG_TRANS, ": rc %p\n", rc);
+                        P9_DPRINTK(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);
+                } else {
+                        spin_unlock_irqrestore(&chan->lock, flags);
+                }
+        } while (rc != NULL);
 }
 
 /**
@@ -199,23 +215,43 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
         int in, out;
         struct virtio_chan *chan = client->trans;
         char *rdata = (char *)req->rc+sizeof(struct p9_fcall);
+        unsigned long flags;
+        int err;
 
         P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio request\n");
 
+req_retry:
+        req->status = REQ_STATUS_SENT;
+
+        spin_lock_irqsave(&chan->lock, flags);
         out = pack_sg_list(chan->sg, 0, VIRTQUEUE_NUM, req->tc->sdata,
                                                                 req->tc->size);
         in = pack_sg_list(chan->sg, out, VIRTQUEUE_NUM-out, rdata,
                                                                 client->msize);
 
-        req->status = REQ_STATUS_SENT;
-
-        if (virtqueue_add_buf(chan->vq, chan->sg, out, in, req->tc) < 0) {
-                P9_DPRINTK(P9_DEBUG_TRANS,
-                        "9p debug: virtio rpc add_buf returned failure");
-                return -EIO;
+        err = virtqueue_add_buf(chan->vq, chan->sg, out, in, req->tc);
+        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_DPRINTK(P9_DEBUG_TRANS, "9p:Retry virtio request\n");
+                        goto req_retry;
+                } else {
+                        spin_unlock_irqrestore(&chan->lock, flags);
+                        P9_DPRINTK(P9_DEBUG_TRANS,
+                                        "9p debug: "
+                                        "virtio rpc add_buf returned failure");
+                        return -EIO;
+                }
         }
 
         virtqueue_kick(chan->vq);
+        spin_unlock_irqrestore(&chan->lock, flags);
 
         P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio request kicked\n");
         return 0;
@@ -290,14 +326,23 @@ static int p9_virtio_probe(struct virtio_device *vdev)
         chan->tag_len = tag_len;
         err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
         if (err) {
-                kfree(tag);
-                goto out_free_vq;
+                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;
+
         mutex_lock(&virtio_9p_lock);
         list_add_tail(&chan->chan_list, &virtio_chan_list);
         mutex_unlock(&virtio_9p_lock);
         return 0;
 
+out_free_tag:
+        kfree(tag);
 out_free_vq:
         vdev->config->del_vqs(vdev);
         kfree(chan);
@@ -371,6 +416,7 @@ static void p9_virtio_remove(struct virtio_device *vdev)
         mutex_unlock(&virtio_9p_lock);
         sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
         kfree(chan->tag);
+        kfree(chan->vc_wq);
         kfree(chan);
 
 }