9p: Optimize TCREATE by eliminating a redundant fid clone.

This patch removes a redundant fid clone on the directory fid and hence
reduces a server transaction while creating new filesystem object.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 6 insertions, 12 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index aecfc0c17945..0ba2db44e0b8 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -504,12 +504,11 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
         ofid = NULL;
         fid = NULL;
         name = (char *) dentry->d_name.name;
-        dfid = v9fs_fid_clone(dentry->d_parent);
+        dfid = v9fs_fid_lookup(dentry->d_parent);
         if (IS_ERR(dfid)) {
                 err = PTR_ERR(dfid);
-                P9_DPRINTK(P9_DEBUG_VFS, "fid clone failed %d\n", err);
-                dfid = NULL;
-                goto error;
+                P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
+                return ERR_PTR(err);
         }
 
         /* clone a fid to use for creation */
@@ -517,8 +516,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
         if (IS_ERR(ofid)) {
                 err = PTR_ERR(ofid);
                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
-                ofid = NULL;
-                goto error;
+                return ERR_PTR(err);
         }
 
         err = p9_client_fcreate(ofid, name, perm, mode, extension);
@@ -528,14 +526,13 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
         }
 
         /* now walk from the parent so we can get unopened fid */
-        fid = p9_client_walk(dfid, 1, &name, 0);
+        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;
-        } else
-                dfid = NULL;
+        }
 
         /* instantiate inode and assign the unopened fid to the dentry */
         inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
@@ -558,9 +555,6 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
         return ofid;
 
 error:
-        if (dfid)
-                p9_client_clunk(dfid);
-
         if (ofid)
                 p9_client_clunk(ofid);