From 1f2030ff6e4958780af9e65a22c39fa8082f292b Mon Sep 17 00:00:00 2001
From: Qu Wenruo <wqu@suse.com>
Date: Tue, 6 Jun 2023 10:05:04 +0800
Subject: [PATCH] btrfs: scrub: respect the read-only flag during repair
[BUG]
With recent scrub rework, the scrub operation no longer respects the
read-only flag passed by "-r" option of "btrfs scrub start" command.
# mkfs.btrfs -f -d raid1 $dev1 $dev2
# mount $dev1 $mnt
# xfs_io -f -d -c "pwrite -b 128K -S 0xaa 0 128k" $mnt/file
# sync
# xfs_io -c "pwrite -S 0xff $phy1 64k" $dev1
# xfs_io -c "pwrite -S 0xff $((phy2 + 65536)) 64k" $dev2
# mount $dev1 $mnt -o ro
# btrfs scrub start -BrRd $mnt
Scrub device $dev1 (id 1) done
Scrub started: Tue Jun 6 09:59:14 2023
Status: finished
Duration: 0:00:00
[...]
corrected_errors: 16 <<< Still has corrupted sectors
last_physical: 1372585984
Scrub device $dev2 (id 2) done
Scrub started: Tue Jun 6 09:59:14 2023
Status: finished
Duration: 0:00:00
[...]
corrected_errors: 16 <<< Still has corrupted sectors
last_physical: 1351614464
# btrfs scrub start -BrRd $mnt
Scrub device $dev1 (id 1) done
Scrub started: Tue Jun 6 10:00:17 2023
Status: finished
Duration: 0:00:00
[...]
corrected_errors: 0 <<< No more errors
last_physical: 1372585984
Scrub device $dev2 (id 2) done
[...]
corrected_errors: 0 <<< No more errors
last_physical: 1372585984
[CAUSE]
In the newly reworked scrub code, repair is always submitted no matter
if we're doing a read-only scrub.
[FIX]
Fix it by skipping the write submission if the scrub is a read-only one.
Unfortunately for the report part, even for a read-only scrub we will
still report it as corrected errors, as we know it's repairable, even we
won't really submit the write.
Fixes: e02ee89baa66 ("btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe infrastructure")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/scrub.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 7c666517d3d33..72c2c093df4bb 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1730,7 +1730,7 @@ static int flush_scrub_stripes(struct scrub_ctx *sctx)
break;
}
}
- } else {
+ } else if (!sctx->readonly) {
for (int i = 0; i < nr_stripes; i++) {
unsigned long repaired;
--
GitLab