4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Josef Bacik jbacik@fb.com
commit fb5c39d7a887108087de6ff93d3f326b01b4ef41 upstream.
max_extent_size is supposed to be the largest contiguous range for the space info, and ctl->free_space is the total free space in the block group. We need to keep track of these separately and _only_ use the max_free_space if we don't have a max_extent_size, as that means our original request was too large to search any of the block groups for and therefore wouldn't have a max_extent_size set.
CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Josef Bacik jbacik@fb.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/extent-tree.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7230,6 +7230,7 @@ static noinline int find_free_extent(str struct btrfs_block_group_cache *block_group = NULL; u64 search_start = 0; u64 max_extent_size = 0; + u64 max_free_space = 0; u64 empty_cluster = 0; struct btrfs_space_info *space_info; int loop = 0; @@ -7525,8 +7526,8 @@ unclustered_alloc: spin_lock(&ctl->tree_lock); if (ctl->free_space < num_bytes + empty_cluster + empty_size) { - if (ctl->free_space > max_extent_size) - max_extent_size = ctl->free_space; + max_free_space = max(max_free_space, + ctl->free_space); spin_unlock(&ctl->tree_lock); goto loop; } @@ -7693,6 +7694,8 @@ loop: } out: if (ret == -ENOSPC) { + if (!max_extent_size) + max_extent_size = max_free_space; spin_lock(&space_info->lock); space_info->max_extent_size = max_extent_size; spin_unlock(&space_info->lock);