[PATCH 01/20] xfs: refactor long-format btree header verification routines

["Darrick J. Wong" <darrick.wong@xxxxxxxxxx>]

Create two helper functions to verify the headers of a long format
btree block.  We'll use this later for the realtime rmapbt.

Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_bmap_btree.c |   22 ++-----------------
 fs/xfs/libxfs/xfs_btree.c      |   47 ++++++++++++++++++++++++++++++++++++++++
 fs/xfs/libxfs/xfs_btree.h      |    3 +++
 3 files changed, 52 insertions(+), 20 deletions(-)


diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
index 1fc3eed..df691d2 100644
--- a/fs/xfs/libxfs/xfs_bmap_btree.c
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -677,17 +677,11 @@ xfs_bmbt_verify(
 
        switch (block->bb_magic) {
        case cpu_to_be32(XFS_BMAP_CRC_MAGIC):
-               if (!xfs_sb_version_hascrc(&mp->m_sb))
-                       return false;
-               if (!uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid))
-                       return false;
-               if (be64_to_cpu(block->bb_u.l.bb_blkno) != bp->b_bn)
-                       return false;
                /*
                 * XXX: need a better way of verifying the owner here. Right now
                 * just make sure there has been one set.
                 */
-               if (be64_to_cpu(block->bb_u.l.bb_owner) == 0)
+               if (!xfs_btree_lblock_v5hdr_verify(bp, XFS_RMAP_OWN_UNKNOWN))
                        return false;
                /* fall through */
        case cpu_to_be32(XFS_BMAP_MAGIC):
@@ -706,20 +700,8 @@ xfs_bmbt_verify(
        level = be16_to_cpu(block->bb_level);
        if (level > max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]))
                return false;
-       if (be16_to_cpu(block->bb_numrecs) > mp->m_bmap_dmxr[level != 0])
-               return false;
-
-       /* sibling pointer verification */
-       if (!block->bb_u.l.bb_leftsib ||
-           (block->bb_u.l.bb_leftsib != cpu_to_be64(NULLFSBLOCK) &&
-            !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_leftsib))))
-               return false;
-       if (!block->bb_u.l.bb_rightsib ||
-           (block->bb_u.l.bb_rightsib != cpu_to_be64(NULLFSBLOCK) &&
-            !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_rightsib))))
-               return false;
 
-       return true;
+       return xfs_btree_lblock_verify(bp, mp->m_bmap_dmxr[level != 0]);
 }
 
 static void
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index a926c54..753e5ed 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -4457,6 +4457,53 @@ xfs_btree_change_owner(
                        &bbcoi);
 }
 
+/* Verify the v5 fields of a long-format btree block. */
+bool
+xfs_btree_lblock_v5hdr_verify(
+       struct xfs_buf          *bp,
+       __uint64_t              owner)
+{
+       struct xfs_mount        *mp = bp->b_target->bt_mount;
+       struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
+
+       if (!xfs_sb_version_hascrc(&mp->m_sb))
+               return false;
+       if (!uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid))
+               return false;
+       if (block->bb_u.l.bb_blkno != cpu_to_be64(bp->b_bn))
+               return false;
+       if (owner != XFS_RMAP_OWN_UNKNOWN &&
+           be64_to_cpu(block->bb_u.l.bb_owner) != owner)
+               return false;
+       return true;
+}
+
+/* Verify a long-format btree block. */
+bool
+xfs_btree_lblock_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.l.bb_leftsib ||
+           (block->bb_u.l.bb_leftsib != cpu_to_be64(NULLFSBLOCK) &&
+            !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_leftsib))))
+               return false;
+       if (!block->bb_u.l.bb_rightsib ||
+           (block->bb_u.l.bb_rightsib != cpu_to_be64(NULLFSBLOCK) &&
+            !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_rightsib))))
+               return false;
+
+       return true;
+}
+
 /**
  * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format
  *                                   btree block
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index f81b2a8..a7770dd 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -513,6 +513,9 @@ static inline int xfs_btree_get_level(struct 
xfs_btree_block *block)
 
 bool xfs_btree_sblock_v5hdr_verify(struct xfs_buf *bp);
 bool xfs_btree_sblock_verify(struct xfs_buf *bp, unsigned int max_recs);
+bool xfs_btree_lblock_v5hdr_verify(struct xfs_buf *bp, __uint64_t owner);
+bool xfs_btree_lblock_verify(struct xfs_buf *bp, unsigned int max_recs);
+
 uint xfs_btree_compute_maxlevels(struct xfs_mount *mp, uint *limits,
                                 unsigned long len);
 xfs_extlen_t xfs_btree_calc_size(struct xfs_mount *mp, uint *limits,