From: Josef Bacik josef@toxicpanda.com
commit 889bfa39086e86b52fcfaa04d72c95eaeb12f9a5 upstream.
If we fsync on a subvolume and create a log root for that volume, and then later delete that subvolume we'll never clean up its log root. Fix this by making switch_commit_roots free the log for any dropped roots we encounter. The extra churn is because we need a btrfs_trans_handle, not the btrfs_transaction.
CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/transaction.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-)
--- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -147,13 +147,14 @@ void btrfs_put_transaction(struct btrfs_ } }
-static noinline void switch_commit_roots(struct btrfs_transaction *trans) +static noinline void switch_commit_roots(struct btrfs_trans_handle *trans) { + struct btrfs_transaction *cur_trans = trans->transaction; struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *root, *tmp;
down_write(&fs_info->commit_root_sem); - list_for_each_entry_safe(root, tmp, &trans->switch_commits, + list_for_each_entry_safe(root, tmp, &cur_trans->switch_commits, dirty_list) { list_del_init(&root->dirty_list); free_extent_buffer(root->commit_root); @@ -165,16 +166,17 @@ static noinline void switch_commit_roots }
/* We can free old roots now. */ - spin_lock(&trans->dropped_roots_lock); - while (!list_empty(&trans->dropped_roots)) { - root = list_first_entry(&trans->dropped_roots, + spin_lock(&cur_trans->dropped_roots_lock); + while (!list_empty(&cur_trans->dropped_roots)) { + root = list_first_entry(&cur_trans->dropped_roots, struct btrfs_root, root_list); list_del_init(&root->root_list); - spin_unlock(&trans->dropped_roots_lock); + spin_unlock(&cur_trans->dropped_roots_lock); + btrfs_free_log(trans, root); btrfs_drop_and_free_fs_root(fs_info, root); - spin_lock(&trans->dropped_roots_lock); + spin_lock(&cur_trans->dropped_roots_lock); } - spin_unlock(&trans->dropped_roots_lock); + spin_unlock(&cur_trans->dropped_roots_lock); up_write(&fs_info->commit_root_sem); }
@@ -1421,7 +1423,7 @@ static int qgroup_account_snapshot(struc ret = commit_cowonly_roots(trans); if (ret) goto out; - switch_commit_roots(trans->transaction); + switch_commit_roots(trans); ret = btrfs_write_and_wait_transaction(trans); if (ret) btrfs_handle_fs_error(fs_info, ret, @@ -2309,7 +2311,7 @@ int btrfs_commit_transaction(struct btrf list_add_tail(&fs_info->chunk_root->dirty_list, &cur_trans->switch_commits);
- switch_commit_roots(cur_trans); + switch_commit_roots(trans);
ASSERT(list_empty(&cur_trans->dirty_bgs)); ASSERT(list_empty(&cur_trans->io_bgs));