On 9.12.19 г. 21:38 ч., Dennis Zhou wrote:
> Returning free space to the free space cache lets it immediately be
> reused. So discard before returning the free space otherwise we can race
> here.
>
> Fixes: 55e734b728c0 ("btrfs: Don't discard unwritten extents")
> Cc: Nikolay Borisov <nborisov@xxxxxxxx>
> Cc: Omar Sandoval <osandov@xxxxxxxxxxx>
> Signed-off-by: Dennis Zhou <dennis@xxxxxxxxxx>
Fair point.
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> fs/btrfs/inode.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 625439875299..1ab13943cdf0 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -3250,13 +3250,14 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
> clear_reserved_extent &&
> !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
> !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
> - btrfs_free_reserved_extent(fs_info,
> - ordered_extent->start,
> - ordered_extent->disk_len, 1);
> if (ret && btrfs_test_opt(fs_info, DISCARD))
> btrfs_discard_extent(fs_info,
> ordered_extent->start,
> ordered_extent->disk_len, NULL);
> +
> + btrfs_free_reserved_extent(fs_info,
> + ordered_extent->start,
> + ordered_extent->disk_len, 1);
> }
> }
>
>
