libxfs: refactor short btree block verification

Create xfs_btree_sblock_verify() to verify short-format btree blocks
(i.e. the per-AG btrees with 32-bit block pointers) instead of
open-coding them.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

fs/xfs/libxfs/xfs_alloc_btree.c

@@ -293,14 +293,7 @@ xfs_allocbt_verify(
 	level = be16_to_cpu(block->bb_level);
 	switch (block->bb_magic) {
 	case cpu_to_be32(XFS_ABTB_CRC_MAGIC):
-		if (!xfs_sb_version_hascrc(&mp->m_sb))
+		if (!xfs_btree_sblock_v5hdr_verify(bp))
-			return false;
-		if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
-			return false;
-		if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
-			return false;
-		if (pag &&
-		    be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 			return false;
 		/* fall through */
 	case cpu_to_be32(XFS_ABTB_MAGIC):
@@ -311,14 +304,7 @@ xfs_allocbt_verify(
 			return false;
 		break;
 	case cpu_to_be32(XFS_ABTC_CRC_MAGIC):
-		if (!xfs_sb_version_hascrc(&mp->m_sb))
+		if (!xfs_btree_sblock_v5hdr_verify(bp))
-			return false;
-		if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
-			return false;
-		if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
-			return false;
-		if (pag &&
-		    be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 			return false;
 		/* fall through */
 	case cpu_to_be32(XFS_ABTC_MAGIC):
@@ -332,21 +318,7 @@ xfs_allocbt_verify(
 		return false;
 	}
 
-	/* numrecs verification */
+	return xfs_btree_sblock_verify(bp, mp->m_alloc_mxr[level != 0]);
-	if (be16_to_cpu(block->bb_numrecs) > mp->m_alloc_mxr[level != 0])
-		return false;
-
-	/* sibling pointer verification */
-	if (!block->bb_u.s.bb_leftsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
-		return false;
-	if (!block->bb_u.s.bb_rightsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
-		return false;
-
-	return true;
 }
 
 static void

fs/xfs/libxfs/xfs_btree.c

@@ -4080,3 +4080,61 @@ xfs_btree_change_owner(
 
 	return 0;
 }
+
+/**
+ * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format
+ *				      btree block
+ *
+ * @bp: buffer containing the btree block
+ * @max_recs: pointer to the m_*_mxr max records field in the xfs mount
+ * @pag_max_level: pointer to the per-ag max level field
+ */
+bool
+xfs_btree_sblock_v5hdr_verify(
+	struct xfs_buf		*bp)
+{
+	struct xfs_mount	*mp = bp->b_target->bt_mount;
+	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
+	struct xfs_perag	*pag = bp->b_pag;
+
+	if (!xfs_sb_version_hascrc(&mp->m_sb))
+		return false;
+	if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
+		return false;
+	if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
+		return false;
+	if (pag && be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
+		return false;
+	return true;
+}
+
+/**
+ * xfs_btree_sblock_verify() -- verify a short-format btree block
+ *
+ * @bp: buffer containing the btree block
+ * @max_recs: maximum records allowed in this btree node
+ */
+bool
+xfs_btree_sblock_verify(
+	struct xfs_buf		*bp,
+	unsigned int		max_recs)
+{
+	struct xfs_mount	*mp = bp->b_target->bt_mount;
+	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
+
+	/* numrecs verification */
+	if (be16_to_cpu(block->bb_numrecs) > max_recs)
+		return false;
+
+	/* sibling pointer verification */
+	if (!block->bb_u.s.bb_leftsib ||
+	    (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
+	     block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
+		return false;
+	if (!block->bb_u.s.bb_rightsib ||
+	    (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
+	     block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
+		return false;
+
+	return true;
+}

fs/xfs/libxfs/xfs_btree.h

@@ -472,4 +472,7 @@ static inline int xfs_btree_get_level(struct xfs_btree_block *block)
 #define XFS_BTREE_TRACE_ARGR(c, r)
 #define	XFS_BTREE_TRACE_CURSOR(c, t)
 
+bool xfs_btree_sblock_v5hdr_verify(struct xfs_buf *bp);
+bool xfs_btree_sblock_verify(struct xfs_buf *bp, unsigned int max_recs);
+
 #endif	/* __XFS_BTREE_H__ */

fs/xfs/libxfs/xfs_ialloc_btree.c

@@ -221,7 +221,6 @@ xfs_inobt_verify(
 {
 	struct xfs_mount	*mp = bp->b_target->bt_mount;
 	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
-	struct xfs_perag	*pag = bp->b_pag;
 	unsigned int		level;
 
 	/*
@@ -237,14 +236,7 @@ xfs_inobt_verify(
 	switch (block->bb_magic) {
 	case cpu_to_be32(XFS_IBT_CRC_MAGIC):
 	case cpu_to_be32(XFS_FIBT_CRC_MAGIC):
-		if (!xfs_sb_version_hascrc(&mp->m_sb))
+		if (!xfs_btree_sblock_v5hdr_verify(bp))
-			return false;
-		if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
-			return false;
-		if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
-			return false;
-		if (pag &&
-		    be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 			return false;
 		/* fall through */
 	case cpu_to_be32(XFS_IBT_MAGIC):
@@ -254,24 +246,12 @@ xfs_inobt_verify(
 		return 0;
 	}
 
-	/* numrecs and level verification */
+	/* level verification */
 	level = be16_to_cpu(block->bb_level);
 	if (level >= mp->m_in_maxlevels)
 		return false;
-	if (be16_to_cpu(block->bb_numrecs) > mp->m_inobt_mxr[level != 0])
-		return false;
 
-	/* sibling pointer verification */
+	return xfs_btree_sblock_verify(bp, mp->m_inobt_mxr[level != 0]);
-	if (!block->bb_u.s.bb_leftsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
-		return false;
-	if (!block->bb_u.s.bb_rightsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
-		return false;
-
-	return true;
 }
 
 static void