btrfs: zoned: zone finish unused block group

While the active zones within an active block group are reset, and their
active resource is released, the block group itself is kept in the active
block group list and marked as active. As a result, the list will contain
more than max_active_zones block groups. That itself is not fatal for the
device as the zones are properly reset.

However, that inflated list is, of course, strange. Also, a to-appear
patch series, which deactivates an active block group on demand, gets
confused with the wrong list.

So, fix the issue by finishing the unused block group once it gets
read-only, so that we can release the active resource in an early stage.

Fixes: 87590247c4c5 ("btrfs: zoned: finish fully written block group")
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 9739f3e8230a355804b7cbe796cb6bfd23d08a18..ede389f2602d5c655aa3ccf1790d9dd72983c47a 100644 (file)
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1385,6 +1385,14 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
                        goto next;
                }
 
+               ret = btrfs_zone_finish(block_group);
+               if (ret < 0) {
+                       btrfs_dec_block_group_ro(block_group);
+                       if (ret == -EAGAIN)
+                               ret = 0;
+                       goto next;
+               }
+
                /*
                 * Want to do this before we do anything else so we can recover
                 * properly if we fail to join the transaction.