From b7e2b579d9690eb2c28c5f37cbc9aaac9e77f000 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Fri, 3 Nov 2017 10:34:44 -0700
Subject: [PATCH 60/77] xfs: iterate backwards in xfs_reflink_cancel_cow_blocks
Git-commit: 41caabd0ab997bcfa9a4822fac32c0803f1cc3df
Patch-mainline: v4.15-rc1
References: bsc#1095344
Match the iteration order for extent deletion in the truncate and
reflink I/O completion path.
This also happens to make implementing the new incore extent list
a lot easier.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
fs/xfs/xfs_reflink.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 7b0fec970185..a89cdf1f89b0 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -566,12 +566,20 @@ xfs_reflink_cancel_cow_blocks(
if (!xfs_is_reflink_inode(ip))
return 0;
- if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &icur, &got))
+ if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
return 0;
- while (got.br_startoff < end_fsb) {
+ /* Walk backwards until we're out of the I/O range... */
+ while (got.br_startoff + got.br_blockcount > offset_fsb) {
del = got;
xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
+
+ /* Extent delete may have bumped ext forward */
+ if (!del.br_blockcount) {
+ xfs_iext_prev(ifp, &icur);
+ goto next_extent;
+ }
+
trace_xfs_reflink_cancel_cow(ip, &del);
if (isnullstartblock(del.br_startblock)) {
@@ -608,8 +616,8 @@ xfs_reflink_cancel_cow_blocks(
/* Remove the mapping from the CoW fork. */
xfs_bmap_del_extent_cow(ip, &icur, &got, &del);
}
-
- if (!xfs_iext_next_extent(ifp, &icur, &got))
+next_extent:
+ if (!xfs_iext_get_extent(ifp, &icur, &got))
break;
}
--
2.7.4