1 files changed, 19 insertions, 10 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 8a2c232f708a..7f6c67703195 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -221,6 +221,7 @@ struct inode *v9fs_alloc_inode(struct super_block *sb)
 #endif
         v9inode->writeback_fid = NULL;
         v9inode->cache_validity = 0;
+        mutex_init(&v9inode->v_mutex);
         return &v9inode->vfs_inode;
 }
 
@@ -650,7 +651,9 @@ 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) {
                 v9inode = V9FS_I(dentry->d_inode);
-                if (v9ses->cache && !v9inode->writeback_fid) {
+                mutex_lock(&v9inode->v_mutex);
+                if (v9ses->cache && !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
@@ -661,10 +664,12 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
                         inode_fid = v9fs_writeback_fid(dentry);
                         if (IS_ERR(inode_fid)) {
                                 err = PTR_ERR(inode_fid);
+                                mutex_unlock(&v9inode->v_mutex);
                                 goto error;
                         }
                         v9inode->writeback_fid = (void *) inode_fid;
                 }
+                mutex_unlock(&v9inode->v_mutex);
                 filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
                 if (IS_ERR(filp)) {
                         err = PTR_ERR(filp);
@@ -931,7 +936,7 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 
         P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
         err = -EPERM;
-        v9ses = v9fs_inode2v9ses(dentry->d_inode);
+        v9ses = v9fs_dentry2v9ses(dentry);
         if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
                 generic_fillattr(dentry->d_inode, stat);
                 return 0;
@@ -967,8 +972,12 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
         struct p9_wstat wstat;
 
         P9_DPRINTK(P9_DEBUG_VFS, "\n");
+        retval = inode_change_ok(dentry->d_inode, iattr);
+        if (retval)
+                return retval;
+
         retval = -EPERM;
-        v9ses = v9fs_inode2v9ses(dentry->d_inode);
+        v9ses = v9fs_dentry2v9ses(dentry);
         fid = v9fs_fid_lookup(dentry);
         if(IS_ERR(fid))
                 return PTR_ERR(fid);
@@ -993,12 +1002,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
                 if (iattr->ia_valid & ATTR_GID)
                         wstat.n_gid = iattr->ia_gid;
         }
-        if ((iattr->ia_valid & ATTR_SIZE) &&
-            iattr->ia_size != i_size_read(dentry->d_inode)) {
-                retval = vmtruncate(dentry->d_inode, iattr->ia_size);
-                if (retval)
-                        return retval;
-        }
+
         /* Write all dirty data */
         if (S_ISREG(dentry->d_inode->i_mode))
                 filemap_write_and_wait(dentry->d_inode->i_mapping);
@@ -1006,6 +1010,11 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
         retval = p9_client_wstat(fid, &wstat);
         if (retval < 0)
                 return retval;
+
+        if ((iattr->ia_valid & ATTR_SIZE) &&
+            iattr->ia_size != i_size_read(dentry->d_inode))
+                truncate_setsize(dentry->d_inode, iattr->ia_size);
+
         v9fs_invalidate_inode_attr(dentry->d_inode);
 
         setattr_copy(dentry->d_inode, iattr);
@@ -1130,7 +1139,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 
         P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
         retval = -EPERM;
-        v9ses = v9fs_inode2v9ses(dentry->d_inode);
+        v9ses = v9fs_dentry2v9ses(dentry);
         fid = v9fs_fid_lookup(dentry);
         if (IS_ERR(fid))
                 return PTR_ERR(fid);