Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux...

[firefly-linux-kernel-4.4.55.git] / fs / xfs / xfs_alloc_btree.c

diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c
index f7876c6d616553d222295624a20f4c168c4c021d..b1ddef6b26892f4f427190833c1265d97be4f57b 100644 (file)
--- a/fs/xfs/xfs_alloc_btree.c
+++ b/fs/xfs/xfs_alloc_btree.c
@@ -272,6 +272,82 @@ xfs_allocbt_key_diff(
        return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 }
 
+static void
+xfs_allocbt_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;
+       unsigned int            level;
+       int                     sblock_ok; /* block passes checks */
+
+       /*
+        * magic number and level verification
+        *
+        * During growfs operations, we can't verify the exact level as the
+        * perag is not fully initialised and hence not attached to the buffer.
+        * In this case, check against the maximum tree depth.
+        */
+       level = be16_to_cpu(block->bb_level);
+       switch (block->bb_magic) {
+       case cpu_to_be32(XFS_ABTB_MAGIC):
+               if (pag)
+                       sblock_ok = level < pag->pagf_levels[XFS_BTNUM_BNOi];
+               else
+                       sblock_ok = level < mp->m_ag_maxlevels;
+               break;
+       case cpu_to_be32(XFS_ABTC_MAGIC):
+               if (pag)
+                       sblock_ok = level < pag->pagf_levels[XFS_BTNUM_CNTi];
+               else
+                       sblock_ok = level < mp->m_ag_maxlevels;
+               break;
+       default:
+               sblock_ok = 0;
+               break;
+       }
+
+       /* numrecs verification */
+       sblock_ok = sblock_ok &&
+               be16_to_cpu(block->bb_numrecs) <= mp->m_alloc_mxr[level != 0];
+
+       /* sibling pointer verification */
+       sblock_ok = sblock_ok &&
+               (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
+                be32_to_cpu(block->bb_u.s.bb_leftsib) < mp->m_sb.sb_agblocks) &&
+               block->bb_u.s.bb_leftsib &&
+               (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
+                be32_to_cpu(block->bb_u.s.bb_rightsib) < mp->m_sb.sb_agblocks) &&
+               block->bb_u.s.bb_rightsib;
+
+       if (!sblock_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_allocbt_read_verify(
+       struct xfs_buf  *bp)
+{
+       xfs_allocbt_verify(bp);
+}
+
+static void
+xfs_allocbt_write_verify(
+       struct xfs_buf  *bp)
+{
+       xfs_allocbt_verify(bp);
+}
+
+const struct xfs_buf_ops xfs_allocbt_buf_ops = {
+       .verify_read = xfs_allocbt_read_verify,
+       .verify_write = xfs_allocbt_write_verify,
+};
+
+
 #ifdef DEBUG
 STATIC int
 xfs_allocbt_keys_inorder(
@@ -327,6 +403,7 @@ static const struct xfs_btree_ops xfs_allocbt_ops = {
        .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
        .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
        .key_diff               = xfs_allocbt_key_diff,
+       .buf_ops                = &xfs_allocbt_buf_ops,
 #ifdef DEBUG
        .keys_inorder           = xfs_allocbt_keys_inorder,
        .recs_inorder           = xfs_allocbt_recs_inorder,