Btrfs: use the tree modification log for backref resolving

This enables backref resolving on life trees while they are changing. This
is a prerequisite for quota groups and just nice to have for everything
else.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This commit is contained in:
Jan Schmidt 2012-05-16 18:36:03 +02:00
parent 5d9e75c41d
commit 8445f61cad
2 changed files with 29 additions and 17 deletions

View File

@ -231,6 +231,7 @@ add_parent:
*/
static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
int search_commit_root,
u64 time_seq,
struct __prelim_ref *ref,
struct ulist *parents,
const u64 *extent_item_pos)
@ -266,7 +267,7 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
goto out;
path->lowest_level = level;
ret = btrfs_search_slot(NULL, root, &ref->key_for_search, path, 0, 0);
ret = btrfs_search_old_slot(root, &ref->key_for_search, path, time_seq);
pr_debug("search slot in root %llu (level %d, ref count %d) returned "
"%d for key (%llu %u %llu)\n",
(unsigned long long)ref->root_id, level, ref->count, ret,
@ -305,7 +306,7 @@ out:
* resolve all indirect backrefs from the list
*/
static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
int search_commit_root,
int search_commit_root, u64 time_seq,
struct list_head *head,
const u64 *extent_item_pos)
{
@ -333,7 +334,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
if (ref->count == 0)
continue;
err = __resolve_indirect_ref(fs_info, search_commit_root,
ref, parents, extent_item_pos);
time_seq, ref, parents,
extent_item_pos);
if (err) {
if (ret == 0)
ret = err;
@ -750,7 +752,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
*/
static int find_parent_nodes(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 seq, struct ulist *refs, struct ulist *roots,
u64 delayed_ref_seq, u64 time_seq,
struct ulist *refs, struct ulist *roots,
const u64 *extent_item_pos)
{
struct btrfs_key key;
@ -813,7 +816,8 @@ again:
btrfs_put_delayed_ref(&head->node);
goto again;
}
ret = __add_delayed_refs(head, seq, &prefs_delayed);
ret = __add_delayed_refs(head, delayed_ref_seq,
&prefs_delayed);
if (ret) {
spin_unlock(&delayed_refs->lock);
goto out;
@ -854,8 +858,8 @@ again:
if (ret)
goto out;
ret = __resolve_indirect_refs(fs_info, search_commit_root, &prefs,
extent_item_pos);
ret = __resolve_indirect_refs(fs_info, search_commit_root, time_seq,
&prefs, extent_item_pos);
if (ret)
goto out;
@ -945,7 +949,8 @@ static void free_leaf_list(struct ulist *blocks)
*/
static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 seq, struct ulist **leafs,
u64 delayed_ref_seq, u64 time_seq,
struct ulist **leafs,
const u64 *extent_item_pos)
{
struct ulist *tmp;
@ -960,8 +965,8 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
return -ENOMEM;
}
ret = find_parent_nodes(trans, fs_info, bytenr, seq, *leafs, tmp,
extent_item_pos);
ret = find_parent_nodes(trans, fs_info, bytenr, delayed_ref_seq,
time_seq, *leafs, tmp, extent_item_pos);
ulist_free(tmp);
if (ret < 0 && ret != -ENOENT) {
@ -987,7 +992,8 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
*/
int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 seq, struct ulist **roots)
u64 delayed_ref_seq, u64 time_seq,
struct ulist **roots)
{
struct ulist *tmp;
struct ulist_node *node = NULL;
@ -1005,8 +1011,8 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
ULIST_ITER_INIT(&uiter);
while (1) {
ret = find_parent_nodes(trans, fs_info, bytenr, seq,
tmp, *roots, NULL);
ret = find_parent_nodes(trans, fs_info, bytenr, delayed_ref_seq,
time_seq, tmp, *roots, NULL);
if (ret < 0 && ret != -ENOENT) {
ulist_free(tmp);
ulist_free(*roots);
@ -1338,7 +1344,8 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
struct ulist *roots = NULL;
struct ulist_node *ref_node = NULL;
struct ulist_node *root_node = NULL;
struct seq_list seq_elem;
struct seq_list seq_elem = {};
struct seq_list tree_mod_seq_elem = {};
struct ulist_iterator ref_uiter;
struct ulist_iterator root_uiter;
struct btrfs_delayed_ref_root *delayed_refs = NULL;
@ -1357,17 +1364,20 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
spin_lock(&delayed_refs->lock);
btrfs_get_delayed_seq(delayed_refs, &seq_elem);
spin_unlock(&delayed_refs->lock);
btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
}
ret = btrfs_find_all_leafs(trans, fs_info, extent_item_objectid,
seq_elem.seq, &refs, &extent_item_pos);
seq_elem.seq, tree_mod_seq_elem.seq, &refs,
&extent_item_pos);
if (ret)
goto out;
ULIST_ITER_INIT(&ref_uiter);
while (!ret && (ref_node = ulist_next(refs, &ref_uiter))) {
ret = btrfs_find_all_roots(trans, fs_info, ref_node->val,
seq_elem.seq, &roots);
seq_elem.seq,
tree_mod_seq_elem.seq, &roots);
if (ret)
break;
ULIST_ITER_INIT(&root_uiter);
@ -1388,6 +1398,7 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
ulist_free(roots);
out:
if (!search_commit_root) {
btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
btrfs_put_delayed_seq(delayed_refs, &seq_elem);
btrfs_end_transaction(trans, fs_info->extent_root);
}

View File

@ -58,7 +58,8 @@ int paths_from_inode(u64 inum, struct inode_fs_paths *ipath);
int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 seq, struct ulist **roots);
u64 delayed_ref_seq, u64 time_seq,
struct ulist **roots);
struct btrfs_data_container *init_data_container(u32 total_bytes);
struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root,