btrfs: make sure we create all new block groups

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>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index d68ee91c00fce4810f6ab85be745bd9b99c5da49..c4a1e8f028d3edf5f4821cce7c99680e9fe8262d 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -10128,7 +10128,7 @@ error:
 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
 {
        struct btrfs_fs_info *fs_info = trans->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;
@@ -10136,7 +10136,10 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans)
        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;