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>
This commit is contained in:
Chris Mason
2008-09-05 16:13:11 -04:00
parent a1b32a5932
commit e02119d5a7
17 changed files with 3408 additions and 205 deletions

View File

@ -202,8 +202,9 @@ again:
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;