From 7467bc5959bf02ef5210ea7e7948e548565c799c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 13 Dec 2024 07:43:43 +0100 Subject: [PATCH] btrfs: zoned: calculate max_extent_size properly on non-zoned setup Since commit 559218d43ec9 ("block: pre-calculate max_zone_append_sectors"), queue_limits's max_zone_append_sectors is default to be 0 and it is only updated when there is a zoned device. So, we have lim->max_zone_append_sectors = 0 when there is no zoned device in the filesystem. That leads to fs_info->max_zone_append_size and thus fs_info->max_extent_size to be 0, which is wrong and can for example lead to a divide by zero in count_max_extents(). Fix this by only capping fs_info->max_extent_size to fs_info->max_zone_append_size when it is non-zero. Based on a patch from Naohiro Aota , from which much of this commit message is stolen as well. Reported-by: Shinichiro Kawasaki Fixes: 559218d43ec9 ("block: pre-calculate max_zone_append_sectors") Tested-by: Shinichiro Kawasaki Reviewed-by: Johannes Thumshirn Reviewed-by: Naohiro Aota Signed-off-by: Christoph Hellwig Signed-off-by: David Sterba --- fs/btrfs/zoned.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index cb32966380f57..5f9d3be1234ab 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -745,8 +745,9 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info) (u64)lim->max_segments << PAGE_SHIFT), fs_info->sectorsize); fs_info->fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_ZONED; - if (fs_info->max_zone_append_size < fs_info->max_extent_size) - fs_info->max_extent_size = fs_info->max_zone_append_size; + + fs_info->max_extent_size = min_not_zero(fs_info->max_extent_size, + fs_info->max_zone_append_size); /* * Check mount options here, because we might change fs_info->zoned -- 2.39.5