[PATCH 4.14 207/222] btrfs: make sure we create all new block groups

Greg Kroah-Hartman
2018-11-11T22:50:38Z

From: Josef Bacik <josef@toxicpanda.com>

commit 545e3366db823dc3342ca9d7fea803f829c9062f upstream.

Allocating new chunks modifies both the extent and chunk tree, which can
trigger new chunk allocations. So instead of doing list_for_each_safe,
just do while (!list_empty()) so we make sure we don't exit with other
pending bg's still on our list.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.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
@@ -10270,7 +10270,7 @@ error:
void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
- struct btrfs_block_group_cache *block_group, *tmp;
+ struct btrfs_block_group_cache *block_group;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_block_group_item item;
struct btrfs_key key;
@@ -10278,7 +10278,10 @@ void btrfs_create_pending_block_groups(s
bool can_flush_pending_bgs = trans->can_flush_pending_bgs;

trans->can_flush_pending_bgs = false;
- list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
+ while (!list_empty(&trans->new_bgs)) {
+ block_group = list_first_entry(&trans->new_bgs,
+ struct btrfs_block_group_cache,
+ bg_list);
if (ret)
goto next;