From 2c47e605a91dde6b0514f689645e7ab336c8592a Mon Sep 17 00:00:00 2001 From: Yan Zheng Date: Sat, 27 Jun 2009 21:07:35 -0400 Subject: Btrfs: update backrefs while dropping snapshot The new backref format has restriction on type of backref item. If a tree block isn't referenced by its owner tree, full backrefs must be used for the pointers in it. When a tree block loses its owner tree's reference, backrefs for the pointers in it should be updated to full backrefs. Current btrfs_drop_snapshot misses the code that updates backrefs, so it's unsafe for general use. This patch adds backrefs update code to btrfs_drop_snapshot. It isn't a problem in the restricted form btrfs_drop_snapshot is used today, but for general snapshot deletion this update is required. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason --- fs/btrfs/relocation.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'fs/btrfs/relocation.c') diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index b23dc209ae10..008397934778 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -1788,7 +1788,7 @@ static void merge_func(struct btrfs_work *work) btrfs_end_transaction(trans, root); } - btrfs_drop_dead_root(reloc_root); + btrfs_drop_snapshot(reloc_root, 0); if (atomic_dec_and_test(async->num_pending)) complete(async->done); @@ -2075,9 +2075,6 @@ static int do_relocation(struct btrfs_trans_handle *trans, ret = btrfs_drop_subtree(trans, root, eb, upper->eb); BUG_ON(ret); - - btrfs_tree_unlock(eb); - free_extent_buffer(eb); } if (!lowest) { btrfs_tree_unlock(upper->eb); -- cgit v1.2.3