Merge tag 'btree-complain-bad-records-6.4_2023-04-11' of git://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into guilt/xfs-for-next

xfs: standardize btree record checking code [v24.5]

While I was cleaning things up for 6.1, I noticed that the btree
_query_range and _query_all functions don't perform the same checking
that the _get_rec functions perform.  In fact, they don't perform /any/
sanity checking, which means that callers aren't warned about impossible
records.

Therefore, hoist the record validation and complaint logging code into
separate functions, and call them from any place where we convert an
ondisk record into an incore record.  For online scrub, we can replace
checking code with a call to the record checking functions in libxfs,
thereby reducing the size of the codebase.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 52 insertions, 25 deletions

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 7ee292aecbeb..b7dc8b81a133 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -95,33 +95,21 @@ xfs_inobt_btrec_to_irec(
 	irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
 }
 
-/*
- * Get the data from the pointed-to record.
- */
-int
-xfs_inobt_get_rec(
-	struct xfs_btree_cur		*cur,
-	struct xfs_inobt_rec_incore	*irec,
-	int				*stat)
+/* Simple checks for inode records. */
+xfs_failaddr_t
+xfs_inobt_check_irec(
+	struct xfs_btree_cur			*cur,
+	const struct xfs_inobt_rec_incore	*irec)
 {
-	struct xfs_mount		*mp = cur->bc_mp;
-	union xfs_btree_rec		*rec;
-	int				error;
 	uint64_t			realfree;
 
-	error = xfs_btree_get_rec(cur, &rec, stat);
-	if (error || *stat == 0)
-		return error;
-
-	xfs_inobt_btrec_to_irec(mp, rec, irec);
-
 	if (!xfs_verify_agino(cur->bc_ag.pag, irec->ir_startino))
-		goto out_bad_rec;
+		return __this_address;
 	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 	    irec->ir_count > XFS_INODES_PER_CHUNK)
-		goto out_bad_rec;
+		return __this_address;
 	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
-		goto out_bad_rec;
+		return __this_address;
 
 	/* if there are no holes, return the first available offset */
 	if (!xfs_inobt_issparse(irec->ir_holemask))
@@ -129,15 +117,23 @@ xfs_inobt_get_rec(
 	else
 		realfree = irec->ir_free & xfs_inobt_irec_to_allocmask(irec);
 	if (hweight64(realfree) != irec->ir_freecount)
-		goto out_bad_rec;
+		return __this_address;
 
-	return 0;
+	return NULL;
+}
+
+static inline int
+xfs_inobt_complain_bad_rec(
+	struct xfs_btree_cur		*cur,
+	xfs_failaddr_t			fa,
+	const struct xfs_inobt_rec_incore *irec)
+{
+	struct xfs_mount		*mp = cur->bc_mp;
 
-out_bad_rec:
 	xfs_warn(mp,
-		"%s Inode BTree record corruption in AG %d detected!",
+		"%s Inode BTree record corruption in AG %d detected at %pS!",
 		cur->bc_btnum == XFS_BTNUM_INO ? "Used" : "Free",
-		cur->bc_ag.pag->pag_agno);
+		cur->bc_ag.pag->pag_agno, fa);
 	xfs_warn(mp,
 "start inode 0x%x, count 0x%x, free 0x%x freemask 0x%llx, holemask 0x%x",
 		irec->ir_startino, irec->ir_count, irec->ir_freecount,
@@ -146,6 +142,32 @@ out_bad_rec:
 }
 
 /*
+ * Get the data from the pointed-to record.
+ */
+int
+xfs_inobt_get_rec(
+	struct xfs_btree_cur		*cur,
+	struct xfs_inobt_rec_incore	*irec,
+	int				*stat)
+{
+	struct xfs_mount		*mp = cur->bc_mp;
+	union xfs_btree_rec		*rec;
+	xfs_failaddr_t			fa;
+	int				error;
+
+	error = xfs_btree_get_rec(cur, &rec, stat);
+	if (error || *stat == 0)
+		return error;
+
+	xfs_inobt_btrec_to_irec(mp, rec, irec);
+	fa = xfs_inobt_check_irec(cur, irec);
+	if (fa)
+		return xfs_inobt_complain_bad_rec(cur, fa, irec);
+
+	return 0;
+}
+
+/*
  * Insert a single inobt record. Cursor must already point to desired location.
  */
 int
@@ -2688,8 +2710,13 @@ xfs_ialloc_count_inodes_rec(
 {
 	struct xfs_inobt_rec_incore	irec;
 	struct xfs_ialloc_count_inodes	*ci = priv;
+	xfs_failaddr_t			fa;
 
 	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
+	fa = xfs_inobt_check_irec(cur, &irec);
+	if (fa)
+		return xfs_inobt_complain_bad_rec(cur, fa, &irec);
+
 	ci->count += irec.ir_count;
 	ci->freecount += irec.ir_freecount;