4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Josef Bacik <josef@xxxxxxxxxxxxxx> commit 21a94f7acf0f748599ea552af5d9ee7d7e41c72f upstream. If we use up our block group before allocating a new one we'll easily get a max_extent_size that's set really really low, which will result in a lot of fragmentation. We need to make sure we're resetting the max_extent_size when we add a new chunk or add new space. CC: stable@xxxxxxxxxxxxxxx # 4.4+ Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/extent-tree.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4530,6 +4530,7 @@ static int do_chunk_alloc(struct btrfs_t goto out; } else { ret = 1; + space_info->max_extent_size = 0; } space_info->force_alloc = CHUNK_ALLOC_NO_FORCE; @@ -6431,6 +6432,7 @@ static int btrfs_free_reserved_bytes(str space_info->bytes_readonly += num_bytes; cache->reserved -= num_bytes; space_info->bytes_reserved -= num_bytes; + space_info->max_extent_size = 0; if (delalloc) cache->delalloc_bytes -= num_bytes;