xfs: consolidate btree block verification

Add a __xfs_btree_check_block helper that can be called by the scrub code
to validate a btree block of any form, and move the duplicate error
handling code from xfs_btree_check_sblock and xfs_btree_check_lblock into
xfs_btree_check_block and thus remove these two helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

fs/xfs/libxfs/xfs_btree.c

@@ -98,7 +98,7 @@ xfs_btree_check_sblock_siblings(
  * Check a long btree block header.  Return the address of the failing check,
  * or NULL if everything is ok.
  */
-xfs_failaddr_t
+static xfs_failaddr_t
 __xfs_btree_check_lblock(
 	struct xfs_btree_cur	*cur,
 	struct xfs_btree_block	*block,
@@ -147,33 +147,11 @@ __xfs_btree_check_lblock(
 	return fa;
 }
 
-/* Check a long btree block header. */
-static int
-xfs_btree_check_lblock(
-	struct xfs_btree_cur	*cur,
-	struct xfs_btree_block	*block,
-	int			level,
-	struct xfs_buf		*bp)
-{
-	struct xfs_mount	*mp = cur->bc_mp;
-	xfs_failaddr_t		fa;
-
-	fa = __xfs_btree_check_lblock(cur, block, level, bp);
-	if (XFS_IS_CORRUPT(mp, fa != NULL) ||
-	    XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BTREE_CHECK_LBLOCK)) {
-		if (bp)
-			trace_xfs_btree_corrupt(bp, _RET_IP_);
-		xfs_btree_mark_sick(cur);
-		return -EFSCORRUPTED;
-	}
-	return 0;
-}
-
 /*
  * Check a short btree block header.  Return the address of the failing check,
  * or NULL if everything is ok.
  */
-xfs_failaddr_t
+static xfs_failaddr_t
 __xfs_btree_check_sblock(
 	struct xfs_btree_cur	*cur,
 	struct xfs_btree_block	*block,
@@ -209,26 +187,28 @@ __xfs_btree_check_sblock(
 	return fa;
 }
 
-/* Check a short btree block header. */
-STATIC int
-xfs_btree_check_sblock(
+/*
+ * Internal btree block check.
+ *
+ * Return NULL if the block is ok or the address of the failed check otherwise.
+ */
+xfs_failaddr_t
+__xfs_btree_check_block(
 	struct xfs_btree_cur	*cur,
 	struct xfs_btree_block	*block,
 	int			level,
 	struct xfs_buf		*bp)
 {
-	struct xfs_mount	*mp = cur->bc_mp;
-	xfs_failaddr_t		fa;
+	if (cur->bc_ops->ptr_len == XFS_BTREE_SHORT_PTR_LEN)
+		return __xfs_btree_check_sblock(cur, block, level, bp);
+	return __xfs_btree_check_lblock(cur, block, level, bp);
+}
 
-	fa = __xfs_btree_check_sblock(cur, block, level, bp);
-	if (XFS_IS_CORRUPT(mp, fa != NULL) ||
-	    XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BTREE_CHECK_SBLOCK)) {
-		if (bp)
-			trace_xfs_btree_corrupt(bp, _RET_IP_);
-		xfs_btree_mark_sick(cur);
-		return -EFSCORRUPTED;
-	}
-	return 0;
+static inline unsigned int xfs_btree_block_errtag(struct xfs_btree_cur *cur)
+{
+	if (cur->bc_ops->ptr_len == XFS_BTREE_SHORT_PTR_LEN)
+		return XFS_ERRTAG_BTREE_CHECK_SBLOCK;
+	return XFS_ERRTAG_BTREE_CHECK_LBLOCK;
 }
 
 /*
@@ -241,10 +221,18 @@ xfs_btree_check_block(
 	int			level,	/* level of the btree block */
 	struct xfs_buf		*bp)	/* buffer containing block, if any */
 {
-	if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
-		return xfs_btree_check_lblock(cur, block, level, bp);
-	else
-		return xfs_btree_check_sblock(cur, block, level, bp);
+	struct xfs_mount	*mp = cur->bc_mp;
+	xfs_failaddr_t		fa;
+
+	fa = __xfs_btree_check_block(cur, block, level, bp);
+	if (XFS_IS_CORRUPT(mp, fa != NULL) ||
+	    XFS_TEST_ERROR(false, mp, xfs_btree_block_errtag(cur))) {
+		if (bp)
+			trace_xfs_btree_corrupt(bp, _RET_IP_);
+		xfs_btree_mark_sick(cur);
+		return -EFSCORRUPTED;
+	}
+	return 0;
 }
 
 int

fs/xfs/libxfs/xfs_btree.h

@@ -334,15 +334,8 @@ xfs_btree_cur_sizeof(unsigned int nlevels)
  */
 #define	XFS_BUF_TO_BLOCK(bp)	((struct xfs_btree_block *)((bp)->b_addr))
 
-/*
- * Internal long and short btree block checks.  They return NULL if the
- * block is ok or the address of the failed check otherwise.
- */
-xfs_failaddr_t __xfs_btree_check_lblock(struct xfs_btree_cur *cur,
+xfs_failaddr_t __xfs_btree_check_block(struct xfs_btree_cur *cur,
 		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
-xfs_failaddr_t __xfs_btree_check_sblock(struct xfs_btree_cur *cur,
-		struct xfs_btree_block *block, int level, struct xfs_buf *bp);
-
 int __xfs_btree_check_ptr(struct xfs_btree_cur *cur,
 		const union xfs_btree_ptr *ptr, int index, int level);
 

fs/xfs/scrub/btree.c

@@ -584,7 +584,6 @@ xchk_btree_get_block(
 	struct xfs_btree_block	**pblock,
 	struct xfs_buf		**pbp)
 {
-	xfs_failaddr_t		failed_at;
 	int			error;
 
 	*pblock = NULL;
@@ -596,13 +595,7 @@ xchk_btree_get_block(
 		return error;
 
 	xfs_btree_get_block(bs->cur, level, pbp);
-	if (bs->cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
-		failed_at = __xfs_btree_check_lblock(bs->cur, *pblock,
-				level, *pbp);
-	else
-		failed_at = __xfs_btree_check_sblock(bs->cur, *pblock,
-				 level, *pbp);
-	if (failed_at) {
+	if (__xfs_btree_check_block(bs->cur, *pblock, level, *pbp)) {
 		xchk_btree_set_corrupt(bs->sc, bs->cur, level);
 		return 0;
 	}