[PATCH] btrfs: zoned: fix comparison of alloc_offset vs meta_write_pointer

[PATCH] btrfs: zoned: fix comparison of alloc_offset vs meta_write_pointer

[Naohiro Aota]

The block_group->alloc_offset is an offset from the start of the block
group. OTOH, the ->meta_write_pointer is an address in the logical
space. So, we should compare the alloc_offset shifted with the
block_group->start.

Fixes: afba2bc036b0 ("btrfs: zoned: implement active zone tracking")
CC: stable@vger.kernel.org # 5.16+
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/zoned.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index db1848a24d44..253cba8c73ca 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1900,7 +1900,7 @@ static int do_zone_finish(struct btrfs_block_group *block_group, bool fully_writ
 	/* Check if we have unwritten allocated space */
 	if ((block_group->flags &
 	     (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_SYSTEM)) &&
-	    block_group->alloc_offset > block_group->meta_write_pointer) {
+	    block_group->start + block_group->alloc_offset > block_group->meta_write_pointer) {
 		spin_unlock(&block_group->lock);
 		return -EAGAIN;
 	}
-- 
2.35.1

Re: [PATCH] btrfs: zoned: fix comparison of alloc_offset vs meta_write_pointer

[David Sterba]

On Wed, May 04, 2022 at 04:12:48PM -0700, Naohiro Aota wrote:
> The block_group->alloc_offset is an offset from the start of the block
> group. OTOH, the ->meta_write_pointer is an address in the logical
> space. So, we should compare the alloc_offset shifted with the
> block_group->start.
> 
> Fixes: afba2bc036b0 ("btrfs: zoned: implement active zone tracking")
> CC: stable@vger.kernel.org # 5.16+
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>

Added to misc-next, thanks.