Btrfs: Add a write ahead tree log to optimize synchronous operations
File syncs and directory syncs are optimized by copying their
items into a special (copy-on-write) log tree. There is one log tree per
subvolume and the btrfs super block points to a tree of log tree roots.
After a crash, items are copied out of the log tree and back into the
subvolume. See tree-log.c for all the details.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 3672669..e3984f9 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -202,8 +202,9 @@
memcpy(&found_key, &key, sizeof(key));
key.offset++;
btrfs_release_path(root, path);
- dead_root = btrfs_read_fs_root_no_radix(root->fs_info,
- &found_key);
+ dead_root =
+ btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
+ &found_key);
if (IS_ERR(dead_root)) {
ret = PTR_ERR(dead_root);
goto err;