Btrfs: reserve space for block groups

This changes our delayed refs calculations to include the space needed
to write back dirty block groups.

Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 8b9eea8f2406..234d6063bbf3 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -251,6 +251,7 @@ loop:
         INIT_LIST_HEAD(&cur_trans->switch_commits);
         INIT_LIST_HEAD(&cur_trans->pending_ordered);
         INIT_LIST_HEAD(&cur_trans->dirty_bgs);
+        cur_trans->num_dirty_bgs = 0;
         spin_lock_init(&cur_trans->dirty_bgs_lock);
         list_add_tail(&cur_trans->list, &fs_info->trans_list);
         extent_io_tree_init(&cur_trans->dirty_pages,