1 files changed, 34 insertions, 19 deletions

diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c
index 8310005af00f..a7174a5b3203 100644
--- a/fs/xfs/xfs_dir2_readdir.c
+++ b/fs/xfs/xfs_dir2_readdir.c
@@ -138,7 +138,8 @@ xfs_dir2_sf_getdents(
 STATIC int
 xfs_dir2_block_getdents(
 	struct xfs_da_args	*args,
-	struct dir_context	*ctx)
+	struct dir_context	*ctx,
+	unsigned int		*lock_mode)
 {
 	struct xfs_inode	*dp = args->dp;	/* incore directory inode */
 	struct xfs_buf		*bp;		/* buffer for block */
@@ -146,7 +147,6 @@ xfs_dir2_block_getdents(
 	int			wantoff;	/* starting block offset */
 	xfs_off_t		cook;
 	struct xfs_da_geometry	*geo = args->geo;
-	int			lock_mode;
 	unsigned int		offset, next_offset;
 	unsigned int		end;
 
@@ -156,12 +156,13 @@ xfs_dir2_block_getdents(
 	if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
 		return 0;
 
-	lock_mode = xfs_ilock_data_map_shared(dp);
 	error = xfs_dir3_block_read(args->trans, dp, &bp);
-	xfs_iunlock(dp, lock_mode);
 	if (error)
 		return error;
 
+	xfs_iunlock(dp, *lock_mode);
+	*lock_mode = 0;
+
 	/*
 	 * Extract the byte offset we start at from the seek pointer.
 	 * We'll skip entries before this.
@@ -344,7 +345,8 @@ STATIC int
 xfs_dir2_leaf_getdents(
 	struct xfs_da_args	*args,
 	struct dir_context	*ctx,
-	size_t			bufsize)
+	size_t			bufsize,
+	unsigned int		*lock_mode)
 {
 	struct xfs_inode	*dp = args->dp;
 	struct xfs_mount	*mp = dp->i_mount;
@@ -356,7 +358,6 @@ xfs_dir2_leaf_getdents(
 	xfs_dir2_off_t		curoff;		/* current overall offset */
 	int			length;		/* temporary length value */
 	int			byteoff;	/* offset in current block */
-	int			lock_mode;
 	unsigned int		offset = 0;
 	int			error = 0;	/* error return value */
 
@@ -390,13 +391,16 @@ xfs_dir2_leaf_getdents(
 				bp = NULL;
 			}
 
-			lock_mode = xfs_ilock_data_map_shared(dp);
+			if (*lock_mode == 0)
+				*lock_mode = xfs_ilock_data_map_shared(dp);
 			error = xfs_dir2_leaf_readbuf(args, bufsize, &curoff,
 					&rablk, &bp);
-			xfs_iunlock(dp, lock_mode);
 			if (error || !bp)
 				break;
 
+			xfs_iunlock(dp, *lock_mode);
+			*lock_mode = 0;
+
 			xfs_dir3_data_check(dp, bp);
 			/*
 			 * Find our position in the block.
@@ -496,7 +500,7 @@ xfs_dir2_leaf_getdents(
  *
  * If supplied, the transaction collects locked dir buffers to avoid
  * nested buffer deadlocks.  This function does not dirty the
- * transaction.  The caller should ensure that the inode is locked
+ * transaction.  The caller must hold the IOLOCK (shared or exclusive)
  * before calling this function.
  */
 int
@@ -507,8 +511,9 @@ xfs_readdir(
 	size_t			bufsize)
 {
 	struct xfs_da_args	args = { NULL };
-	int			rval;
-	int			v;
+	unsigned int		lock_mode;
+	int			isblock;
+	int			error;
 
 	trace_xfs_readdir(dp);
 
@@ -516,6 +521,7 @@ xfs_readdir(
 		return -EIO;
 
 	ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
+	ASSERT(xfs_isilocked(dp, XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 	XFS_STATS_INC(dp->i_mount, xs_dir_getdents);
 
 	args.dp = dp;
@@ -523,13 +529,22 @@ xfs_readdir(
 	args.trans = tp;
 
 	if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL)
-		rval = xfs_dir2_sf_getdents(&args, ctx);
-	else if ((rval = xfs_dir2_isblock(&args, &v)))
-		;
-	else if (v)
-		rval = xfs_dir2_block_getdents(&args, ctx);
-	else
-		rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
+		return xfs_dir2_sf_getdents(&args, ctx);
 
-	return rval;
+	lock_mode = xfs_ilock_data_map_shared(dp);
+	error = xfs_dir2_isblock(&args, &isblock);
+	if (error)
+		goto out_unlock;
+
+	if (isblock) {
+		error = xfs_dir2_block_getdents(&args, ctx, &lock_mode);
+		goto out_unlock;
+	}
+
+	error = xfs_dir2_leaf_getdents(&args, ctx, bufsize, &lock_mode);
+
+out_unlock:
+	if (lock_mode)
+		xfs_iunlock(dp, lock_mode);
+	return error;
 }