xfs: don't update rmapbt when fixing agfl
Allow a caller of xfs_alloc_fix_freelist to disable rmapbt updates
when fixing the AG freelist. xfs_repair needs this during phase 5
to be able to adjust the freelist while it's reconstructing the rmap
btree; the missing entries will be added back at the very end of
phase 5 once the AGFL contents settle down.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 73ab1ea..a0dc299 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2090,9 +2090,21 @@
* anything other than extra overhead when we need to put more blocks
* back on the free list? Maybe we should only do this when space is
* getting low or the AGFL is more than half full?
+ *
+ * The NOSHRINK flag prevents the AGFL from being shrunk if it's too
+ * big; the NORMAP flag prevents AGFL expand/shrink operations from
+ * updating the rmapbt. Both flags are used in xfs_repair while we're
+ * rebuilding the rmapbt, and neither are used by the kernel. They're
+ * both required to ensure that rmaps are correctly recorded for the
+ * regenerated AGFL, bnobt, and cntbt. See repair/phase5.c and
+ * repair/rmap.c in xfsprogs for details.
*/
- xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG);
- while (pag->pagf_flcount > need) {
+ memset(&targs, 0, sizeof(targs));
+ if (flags & XFS_ALLOC_FLAG_NORMAP)
+ xfs_rmap_skip_owner_update(&targs.oinfo);
+ else
+ xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG);
+ while (!(flags & XFS_ALLOC_FLAG_NOSHRINK) && pag->pagf_flcount > need) {
struct xfs_buf *bp;
error = xfs_alloc_get_freelist(tp, agbp, &bno, 0);
@@ -2106,10 +2118,8 @@
xfs_trans_binval(tp, bp);
}
- memset(&targs, 0, sizeof(targs));
targs.tp = tp;
targs.mp = mp;
- xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG);
targs.agbp = agbp;
targs.agno = args->agno;
targs.alignment = targs.minlen = targs.prod = targs.isfl = 1;