Btrfs: fix leaking block group on balance

The block group structs are referenced in many different
places, and it's not safe to free while balancing.  So, those block
group structs were simply leaked instead.

This patch replaces the block group pointer in the inode with the starting byte
offset of the block group and adds reference counting to the block group
struct.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 202c8be6c05d..ffe7f639732b 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -41,7 +41,7 @@ struct btrfs_trans_handle {
         unsigned long blocks_reserved;
         unsigned long blocks_used;
         struct btrfs_transaction *transaction;
-        struct btrfs_block_group_cache *block_group;
+        u64 block_group;
         u64 alloc_exclude_start;
         u64 alloc_exclude_nr;
 };