retval = PTR_ERR(inode);
                goto release_sb;
        }
-
        root = d_alloc_root(inode);
        if (!root) {
                iput(inode);
                p9stat_free(st);
                kfree(st);
        }
+       v9fs_fid_add(root, fid);
        retval = v9fs_get_acl(inode, fid);
        if (retval)
                goto release_sb;
-       v9fs_fid_add(root, fid);
+       /*
+        * Add the root fid to session info. This is used
+        * for file system sync. We want a cloned fid here
+        * so that we can do a sync_filesystem after a
+        * shrink_dcache_for_umount
+        */
+       v9ses->root_fid = v9fs_fid_clone(root);
+       if (IS_ERR(v9ses->root_fid)) {
+               retval = PTR_ERR(v9ses->root_fid);
+               goto release_sb;
+       }
 
        P9_DPRINTK(P9_DEBUG_VFS, " simple set mount, return 0\n");
        return dget(sb->s_root);
        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.
+        * we will do the session_close and root dentry
+        * release in the below call.
         */
-       p9_client_clunk(fid);
        deactivate_locked_super(sb);
        return ERR_PTR(retval);
 }
        P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s);
 
        kill_anon_super(s);
-
+       p9_client_clunk(v9ses->root_fid);
        v9fs_session_cancel(v9ses);
        v9fs_session_close(v9ses);
        kfree(v9ses);
        return res;
 }
 
+static int v9fs_sync_fs(struct super_block *sb, int wait)
+{
+       struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+       P9_DPRINTK(P9_DEBUG_VFS, "v9fs_sync_fs: super_block %p\n", sb);
+       return p9_client_sync_fs(v9ses->root_fid);
+}
+
 static const struct super_operations v9fs_super_ops = {
 #ifdef CONFIG_9P_FSCACHE
        .alloc_inode = v9fs_alloc_inode,
        .alloc_inode = v9fs_alloc_inode,
        .destroy_inode = v9fs_destroy_inode,
 #endif
+       .sync_fs = v9fs_sync_fs,
        .statfs = v9fs_statfs,
        .evict_inode = v9fs_evict_inode,
        .show_options = generic_show_options,