[PATCH 093/110] xfs: add a xfs_btree_ptrs_equal helper

Darrick J. Wong
2024-03-26T03:52:42Z

From: Christoph Hellwig <hch@lst.de>

Source kernel commit: 8c1771c45dfa9dddd4569727c48204b66073d2c2

This only has a single caller and thus might be a bit questionable,
but I think it really improves the readability of
xfs_btree_visit_block.

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>
---
libxfs/xfs_btree.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/libxfs/xfs_btree.c b/libxfs/xfs_btree.c
index a989b2da2dd5..5fd966a63371 100644
--- a/libxfs/xfs_btree.c
+++ b/libxfs/xfs_btree.c
@@ -1040,6 +1040,17 @@ xfs_btree_set_ptr_null(
ptr->s = cpu_to_be32(NULLAGBLOCK);
}

+static inline bool
+xfs_btree_ptrs_equal(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr1,
+ union xfs_btree_ptr *ptr2)
+{
+ if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN)
+ return ptr1->l == ptr2->l;
+ return ptr1->s == ptr2->s;
+}
+
/*
* Get/set/init sibling pointers
*/
@@ -4362,7 +4373,7 @@ xfs_btree_visit_block(
{
struct xfs_btree_block *block;
struct xfs_buf *bp;
- union xfs_btree_ptr rptr;
+ union xfs_btree_ptr rptr, bufptr;
int error;

/* do right sibling readahead */
@@ -4385,19 +4396,12 @@ xfs_btree_visit_block(
* return the same block without checking if the right sibling points
* back to us and creates a cyclic reference in the btree.
*/
- if (cur->bc_ops->ptr_len == XFS_BTREE_LONG_PTR_LEN) {
- if (be64_to_cpu(rptr.l) == XFS_DADDR_TO_FSB(cur->bc_mp,
- xfs_buf_daddr(bp))) {
- xfs_btree_mark_sick(cur);
- return -EFSCORRUPTED;
- }
- } else {
- if (be32_to_cpu(rptr.s) == xfs_daddr_to_agbno(cur->bc_mp,
- xfs_buf_daddr(bp))) {
- xfs_btree_mark_sick(cur);
- return -EFSCORRUPTED;
- }
+ xfs_btree_buf_to_ptr(cur, bp, &bufptr);
+ if (xfs_btree_ptrs_equal(cur, &rptr, &bufptr)) {
+ xfs_btree_mark_sick(cur);
+ return -EFSCORRUPTED;
}
+
return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
}