xfs: Hold inode locks in xfs_rename

Modify xfs_rename to hold all inode locks across a rename operation
We will need this later when we add parent pointers
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Catherine Hoang <catherine.hoang@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/xfs_inode.c

@@ -2804,6 +2804,21 @@ xfs_remove(
 	return error;
 }
 
+static inline void
+xfs_iunlock_rename(
+	struct xfs_inode	**i_tab,
+	int			num_inodes)
+{
+	int			i;
+
+	for (i = num_inodes - 1; i >= 0; i--) {
+		/* Skip duplicate inodes if src and target dps are the same */
+		if (!i_tab[i] || (i > 0 && i_tab[i] == i_tab[i - 1]))
+			continue;
+		xfs_iunlock(i_tab[i], XFS_ILOCK_EXCL);
+	}
+}
+
 /*
  * Enter all inodes for a rename transaction into a sorted array.
  */
@@ -3113,8 +3128,10 @@ xfs_rename(
 	 * Attach the dquots to the inodes
 	 */
 	error = xfs_qm_vop_rename_dqattach(inodes);
-	if (error)
-		goto out_trans_cancel;
+	if (error) {
+		xfs_trans_cancel(tp);
+		goto out_release_wip;
+	}
 
 	/*
 	 * Lock all the participating inodes. Depending upon whether
@@ -3125,18 +3142,16 @@ xfs_rename(
 	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
 
 	/*
-	 * Join all the inodes to the transaction. From this point on,
-	 * we can rely on either trans_commit or trans_cancel to unlock
-	 * them.
+	 * Join all the inodes to the transaction.
 	 */
-	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
+	xfs_trans_ijoin(tp, src_dp, 0);
 	if (new_parent)
-		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
-	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
+		xfs_trans_ijoin(tp, target_dp, 0);
+	xfs_trans_ijoin(tp, src_ip, 0);
 	if (target_ip)
-		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
+		xfs_trans_ijoin(tp, target_ip, 0);
 	if (wip)
-		xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
+		xfs_trans_ijoin(tp, wip, 0);
 
 	/*
 	 * If we are using project inheritance, we only allow renames
@@ -3150,10 +3165,13 @@ xfs_rename(
 	}
 
 	/* RENAME_EXCHANGE is unique from here on. */
-	if (flags & RENAME_EXCHANGE)
-		return xfs_cross_rename(tp, src_dp, src_name, src_ip,
+	if (flags & RENAME_EXCHANGE) {
+		error = xfs_cross_rename(tp, src_dp, src_name, src_ip,
 					target_dp, target_name, target_ip,
 					spaceres);
+		xfs_iunlock_rename(inodes, num_inodes);
+		return error;
+	}
 
 	/*
 	 * Try to reserve quota to handle an expansion of the target directory.
@@ -3167,6 +3185,7 @@ xfs_rename(
 		if (error == -EDQUOT || error == -ENOSPC) {
 			if (!retried) {
 				xfs_trans_cancel(tp);
+				xfs_iunlock_rename(inodes, num_inodes);
 				xfs_blockgc_free_quota(target_dp, 0);
 				retried = true;
 				goto retry;
@@ -3393,12 +3412,14 @@ xfs_rename(
 		xfs_dir_update_hook(src_dp, wip, 1, src_name);
 
 	error = xfs_finish_rename(tp);
+	xfs_iunlock_rename(inodes, num_inodes);
 	if (wip)
 		xfs_irele(wip);
 	return error;
 
 out_trans_cancel:
 	xfs_trans_cancel(tp);
+	xfs_iunlock_rename(inodes, num_inodes);
 out_release_wip:
 	if (wip)
 		xfs_irele(wip);