[PATCH] btrfs: zoned: use zone aware sb location for scrub

[Johannes Thumshirn <jth@kernel.org>]

From: Johannes Thumshirn <johannes.thumshirn@wdc.com>

At the moment scrub_supers() doesn't grab the super block's location via
the zoned device aware btrfs_sb_log_location() but via btrfs_sb_offset().

This leads to checksum errors on 'scrub' as we're not accessing the
correct location of the super block.

So use btrfs_sb_log_location() for getting the super blocks location on
scrub.

Reported-by: WA AM <waautomata@gmail.com>
Link: http://lore.kernel.org/linux-btrfs/CANU2Z0EvUzfYxczLgGUiREoMndE9WdQnbaawV5Fv5gNXptPUKw@mail.gmail.com
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 fs/btrfs/scrub.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index c4bd0e60db59..3c8fd9c9fa1d 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2812,7 +2812,10 @@ static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
 		gen = btrfs_get_last_trans_committed(fs_info);
 
 	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
-		bytenr = btrfs_sb_offset(i);
+		ret = btrfs_sb_log_location(scrub_dev, i, 0, &bytenr);
+		if (ret)
+			goto out_free_page;
+
 		if (bytenr + BTRFS_SUPER_INFO_SIZE >
 		    scrub_dev->commit_total_bytes)
 			break;
@@ -2828,6 +2831,13 @@ static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
 	}
 	__free_page(page);
 	return 0;
+
+out_free_page:
+	spin_lock(&sctx->stat_lock);
+	sctx->stat.malloc_errors++;
+	spin_unlock(&sctx->stat_lock);
+	__free_page(page);
+	return ret;
 }
 
 static void scrub_workers_put(struct btrfs_fs_info *fs_info)
-- 
2.35.3