xfs: flag free space btree records that could be merged

Complain if we encounter free space btree records that could be merged.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/scrub/alloc.c b/fs/xfs/scrub/alloc.c
index 12dd55ac2a4f1e78b38c476058af61810d99eacc..279af72b1671d91171638115463d0ed93a84c28c 100644 (file)
--- a/fs/xfs/scrub/alloc.c
+++ b/fs/xfs/scrub/alloc.c
@@ -31,6 +31,12 @@ xchk_setup_ag_allocbt(
 }
 
 /* Free space btree scrubber. */
+
+struct xchk_alloc {
+       /* Previous free space extent. */
+       struct xfs_alloc_rec_incore     prev;
+};
+
 /*
  * Ensure there's a corresponding cntbt/bnobt record matching this
  * bnobt/cntbt record, respectively.
@@ -93,6 +99,24 @@ xchk_allocbt_xref(
        xchk_xref_is_not_cow_staging(sc, agbno, len);
 }
 
+/* Flag failures for records that could be merged. */
+STATIC void
+xchk_allocbt_mergeable(
+       struct xchk_btree       *bs,
+       struct xchk_alloc       *ca,
+       const struct xfs_alloc_rec_incore *irec)
+{
+       if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+               return;
+
+       if (ca->prev.ar_blockcount > 0 &&
+           ca->prev.ar_startblock + ca->prev.ar_blockcount == irec->ar_startblock &&
+           ca->prev.ar_blockcount + irec->ar_blockcount < (uint32_t)~0U)
+               xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+
+       memcpy(&ca->prev, irec, sizeof(*irec));
+}
+
 /* Scrub a bnobt/cntbt record. */
 STATIC int
 xchk_allocbt_rec(
@@ -100,6 +124,7 @@ xchk_allocbt_rec(
        const union xfs_btree_rec       *rec)
 {
        struct xfs_alloc_rec_incore     irec;
+       struct xchk_alloc       *ca = bs->private;
 
        xfs_alloc_btrec_to_irec(rec, &irec);
        if (xfs_alloc_check_irec(bs->cur, &irec) != NULL) {
@@ -107,6 +132,7 @@ xchk_allocbt_rec(
                return 0;
        }
 
+       xchk_allocbt_mergeable(bs, ca, &irec);
        xchk_allocbt_xref(bs->sc, &irec);
 
        return 0;
@@ -118,10 +144,11 @@ xchk_allocbt(
        struct xfs_scrub        *sc,
        xfs_btnum_t             which)
 {
+       struct xchk_alloc       ca = { };
        struct xfs_btree_cur    *cur;
 
        cur = which == XFS_BTNUM_BNO ? sc->sa.bno_cur : sc->sa.cnt_cur;
-       return xchk_btree(sc, cur, xchk_allocbt_rec, &XFS_RMAP_OINFO_AG, NULL);
+       return xchk_btree(sc, cur, xchk_allocbt_rec, &XFS_RMAP_OINFO_AG, &ca);
 }
 
 int