ceph: clear dir complete, invalidate dentry on replayed rename

If a rename operation is resent to the MDS following an MDS restart, the
client does not get a full reply (containing the resulting metadata) back.
In that case, a ceph_rename() needs to compensate by doing anything useful
that fill_inode() would have, like d_move().

It also needs to invalidate the dentry (to workaround the vfs_rename_dir()
bug) and clear the dir complete flag, just like fill_trace().
Signed-off-by: Sage Weil <sage@newdream.net>

fs/ceph/dir.c

@@ -880,7 +880,16 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 		 * do_request, above).  If there is no trace, we need
 		 * to do it here.
 		 */
+
+		/* d_move screws up d_subdirs order */
+		ceph_i_clear(new_dir, CEPH_I_COMPLETE);
+
 		d_move(old_dentry, new_dentry);
+
+		/* ensure target dentry is invalidated, despite
+		   rehashing bug in vfs_rename_dir */
+		new_dentry->d_time = jiffies;
+		ceph_dentry(new_dentry)->lease_shared_gen = 0;
 	}
 	ceph_mdsc_put_request(req);
 	return err;