vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fhandle.c b/fs/fhandle.c
index 5eff711..a48e4a1 100644
--- a/fs/fhandle.c
+++ b/fs/fhandle.c
@@ -25,8 +25,8 @@
 	 * We need t make sure wether the file system
 	 * support decoding of the file handle
 	 */
-	if (!path->mnt->mnt_sb->s_export_op ||
-	    !path->mnt->mnt_sb->s_export_op->fh_to_dentry)
+	if (!path->dentry->d_sb->s_export_op ||
+	    !path->dentry->d_sb->s_export_op->fh_to_dentry)
 		return -EOPNOTSUPP;
 
 	if (copy_from_user(&f_handle, ufh, sizeof(struct file_handle)))