From b9fd2affe4aa99a4ca14ee87e1f38fea22ece52a Mon Sep 17 00:00:00 2001 From: Naohiro Aota Date: Tue, 11 Jun 2024 17:17:30 +0900 Subject: btrfs: zoned: fix initial free space detection When creating a new block group, it calls btrfs_add_new_free_space() to add the entire block group range into the free space accounting. __btrfs_add_free_space_zoned() checks if size == block_group->length to detect the initial free space adding, and proceed that case properly. However, if the zone_capacity == zone_size and the over-write speed is fast enough, the entire zone can be over-written within one transaction. That confuses __btrfs_add_free_space_zoned() to handle it as an initial free space accounting. As a result, that block group becomes a strange state: 0 used bytes, 0 zone_unusable bytes, but alloc_offset == zone_capacity (no allocation anymore). The initial free space accounting can properly be checked by checking alloc_offset too. Fixes: 98173255bddd ("btrfs: zoned: calculate free space from zone capacity") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Johannes Thumshirn Signed-off-by: Naohiro Aota Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/free-space-cache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index c8a05d5eb9cb..b642df5e5255 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -2697,7 +2697,7 @@ static int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group, u64 offset = bytenr - block_group->start; u64 to_free, to_unusable; int bg_reclaim_threshold = 0; - bool initial = (size == block_group->length); + bool initial = ((size == block_group->length) && (block_group->alloc_offset == 0)); u64 reclaimable_unusable; WARN_ON(!initial && offset + size > block_group->zone_capacity); -- cgit v1.2.3