xfs: convert buffer verifiers to an ops structure.

[deliverable/linux.git] / fs / xfs / xfs_bmap_btree.c

diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c
index 862084a47a7e269a8ab4357d5bf75906688ee86c..061b45cbe61461a5aa1f1d93f25deb2ec8b23d01 100644 (file)
--- a/fs/xfs/xfs_bmap_btree.c
+++ b/fs/xfs/xfs_bmap_btree.c
@@ -36,6 +36,7 @@
 #include "xfs_bmap.h"
 #include "xfs_error.h"
 #include "xfs_quota.h"
+#include "xfs_trace.h"
 
 /*
  * Determine the extent state.
@@ -707,6 +708,67 @@ xfs_bmbt_key_diff(
                                      cur->bc_rec.b.br_startoff;
 }
 
+static void
+xfs_bmbt_verify(
+       struct xfs_buf          *bp)
+{
+       struct xfs_mount        *mp = bp->b_target->bt_mount;
+       struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
+       unsigned int            level;
+       int                     lblock_ok; /* block passes checks */
+
+       /* magic number and level verification.
+        *
+        * We don't know waht fork we belong to, so just verify that the level
+        * is less than the maximum of the two. Later checks will be more
+        * precise.
+        */
+       level = be16_to_cpu(block->bb_level);
+       lblock_ok = block->bb_magic == cpu_to_be32(XFS_BMAP_MAGIC) &&
+                   level < max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]);
+
+       /* numrecs verification */
+       lblock_ok = lblock_ok &&
+               be16_to_cpu(block->bb_numrecs) <= mp->m_bmap_dmxr[level != 0];
+
+       /* sibling pointer verification */
+       lblock_ok = lblock_ok &&
+               block->bb_u.l.bb_leftsib &&
+               (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO) ||
+                XFS_FSB_SANITY_CHECK(mp,
+                       be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
+               block->bb_u.l.bb_rightsib &&
+               (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO) ||
+                XFS_FSB_SANITY_CHECK(mp,
+                       be64_to_cpu(block->bb_u.l.bb_rightsib)));
+
+       if (!lblock_ok) {
+               trace_xfs_btree_corrupt(bp, _RET_IP_);
+               XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, block);
+               xfs_buf_ioerror(bp, EFSCORRUPTED);
+       }
+}
+
+static void
+xfs_bmbt_read_verify(
+       struct xfs_buf  *bp)
+{
+       xfs_bmbt_verify(bp);
+}
+
+static void
+xfs_bmbt_write_verify(
+       struct xfs_buf  *bp)
+{
+       xfs_bmbt_verify(bp);
+}
+
+const struct xfs_buf_ops xfs_bmbt_buf_ops = {
+       .verify_read = xfs_bmbt_read_verify,
+       .verify_write = xfs_bmbt_write_verify,
+};
+
+
 #ifdef DEBUG
 STATIC int
 xfs_bmbt_keys_inorder(
@@ -746,6 +808,7 @@ static const struct xfs_btree_ops xfs_bmbt_ops = {
        .init_rec_from_cur      = xfs_bmbt_init_rec_from_cur,
        .init_ptr_from_cur      = xfs_bmbt_init_ptr_from_cur,
        .key_diff               = xfs_bmbt_key_diff,
+       .buf_ops                = &xfs_bmbt_buf_ops,
 #ifdef DEBUG
        .keys_inorder           = xfs_bmbt_keys_inorder,
        .recs_inorder           = xfs_bmbt_recs_inorder,