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authorQu Wenruo <wqu@suse.com>2020-03-23 11:08:34 +0300
committerDavid Sterba <dsterba@suse.com>2020-05-25 12:25:21 +0300
commit1b60d2ec982a35c2953d81d035e1d7fc7c89f42a (patch)
tree850c3ca66abe283c0658a427c694bbece11b438c /fs/btrfs/relocation.c
parentd36e7f0e8fedd0675789b4fc5869d8d48d33e18a (diff)
downloadlinux-1b60d2ec982a35c2953d81d035e1d7fc7c89f42a.tar.xz
btrfs: backref: rename and move handle_one_tree_block()
This function is the major part of backref cache build process, move it to backref.c so we can reuse it later. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/relocation.c')
-rw-r--r--fs/btrfs/relocation.c357
1 files changed, 2 insertions, 355 deletions
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index b8fc07ad0a64..275e4c9e9685 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -378,360 +378,6 @@ static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info,
}
/*
- * Handle direct tree backref
- *
- * Direct tree backref means, the backref item shows its parent bytenr
- * directly. This is for SHARED_BLOCK_REF backref (keyed or inlined).
- *
- * @ref_key: The converted backref key.
- * For keyed backref, it's the item key.
- * For inlined backref, objectid is the bytenr,
- * type is btrfs_inline_ref_type, offset is
- * btrfs_inline_ref_offset.
- */
-static int handle_direct_tree_backref(struct btrfs_backref_cache *cache,
- struct btrfs_key *ref_key,
- struct btrfs_backref_node *cur)
-{
- struct btrfs_backref_edge *edge;
- struct btrfs_backref_node *upper;
- struct rb_node *rb_node;
-
- ASSERT(ref_key->type == BTRFS_SHARED_BLOCK_REF_KEY);
-
- /* Only reloc root uses backref pointing to itself */
- if (ref_key->objectid == ref_key->offset) {
- struct btrfs_root *root;
-
- cur->is_reloc_root = 1;
- /* Only reloc backref cache cares about a specific root */
- if (cache->is_reloc) {
- root = find_reloc_root(cache->fs_info, cur->bytenr);
- if (WARN_ON(!root))
- return -ENOENT;
- cur->root = root;
- } else {
- /*
- * For generic purpose backref cache, reloc root node
- * is useless.
- */
- list_add(&cur->list, &cache->useless_node);
- }
- return 0;
- }
-
- edge = btrfs_backref_alloc_edge(cache);
- if (!edge)
- return -ENOMEM;
-
- rb_node = rb_simple_search(&cache->rb_root, ref_key->offset);
- if (!rb_node) {
- /* Parent node not yet cached */
- upper = btrfs_backref_alloc_node(cache, ref_key->offset,
- cur->level + 1);
- if (!upper) {
- btrfs_backref_free_edge(cache, edge);
- return -ENOMEM;
- }
-
- /*
- * Backrefs for the upper level block isn't cached, add the
- * block to pending list
- */
- list_add_tail(&edge->list[UPPER], &cache->pending_edge);
- } else {
- /* Parent node already cached */
- upper = rb_entry(rb_node, struct btrfs_backref_node, rb_node);
- ASSERT(upper->checked);
- INIT_LIST_HEAD(&edge->list[UPPER]);
- }
- btrfs_backref_link_edge(edge, cur, upper, LINK_LOWER);
- return 0;
-}
-
-/*
- * Handle indirect tree backref
- *
- * Indirect tree backref means, we only know which tree the node belongs to.
- * We still need to do a tree search to find out the parents. This is for
- * TREE_BLOCK_REF backref (keyed or inlined).
- *
- * @ref_key: The same as @ref_key in handle_direct_tree_backref()
- * @tree_key: The first key of this tree block.
- * @path: A clean (released) path, to avoid allocating path everytime
- * the function get called.
- */
-static int handle_indirect_tree_backref(struct btrfs_backref_cache *cache,
- struct btrfs_path *path,
- struct btrfs_key *ref_key,
- struct btrfs_key *tree_key,
- struct btrfs_backref_node *cur)
-{
- struct btrfs_fs_info *fs_info = cache->fs_info;
- struct btrfs_backref_node *upper;
- struct btrfs_backref_node *lower;
- struct btrfs_backref_edge *edge;
- struct extent_buffer *eb;
- struct btrfs_root *root;
- struct btrfs_key root_key;
- struct rb_node *rb_node;
- int level;
- bool need_check = true;
- int ret;
-
- root_key.objectid = ref_key->offset;
- root_key.type = BTRFS_ROOT_ITEM_KEY;
- root_key.offset = (u64)-1;
- root = btrfs_get_fs_root(fs_info, &root_key, false);
- if (IS_ERR(root))
- return PTR_ERR(root);
- if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
- cur->cowonly = 1;
-
- if (btrfs_root_level(&root->root_item) == cur->level) {
- /* Tree root */
- ASSERT(btrfs_root_bytenr(&root->root_item) == cur->bytenr);
- if (btrfs_should_ignore_reloc_root(root)) {
- btrfs_put_root(root);
- list_add(&cur->list, &cache->useless_node);
- } else {
- cur->root = root;
- }
- return 0;
- }
-
- level = cur->level + 1;
-
- /* Search the tree to find parent blocks referring to the block */
- path->search_commit_root = 1;
- path->skip_locking = 1;
- path->lowest_level = level;
- ret = btrfs_search_slot(NULL, root, tree_key, path, 0, 0);
- path->lowest_level = 0;
- if (ret < 0) {
- btrfs_put_root(root);
- return ret;
- }
- if (ret > 0 && path->slots[level] > 0)
- path->slots[level]--;
-
- eb = path->nodes[level];
- if (btrfs_node_blockptr(eb, path->slots[level]) != cur->bytenr) {
- btrfs_err(fs_info,
-"couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)",
- cur->bytenr, level - 1, root->root_key.objectid,
- tree_key->objectid, tree_key->type, tree_key->offset);
- btrfs_put_root(root);
- ret = -ENOENT;
- goto out;
- }
- lower = cur;
-
- /* Add all nodes and edges in the path */
- for (; level < BTRFS_MAX_LEVEL; level++) {
- if (!path->nodes[level]) {
- ASSERT(btrfs_root_bytenr(&root->root_item) ==
- lower->bytenr);
- if (btrfs_should_ignore_reloc_root(root)) {
- btrfs_put_root(root);
- list_add(&lower->list, &cache->useless_node);
- } else {
- lower->root = root;
- }
- break;
- }
-
- edge = btrfs_backref_alloc_edge(cache);
- if (!edge) {
- btrfs_put_root(root);
- ret = -ENOMEM;
- goto out;
- }
-
- eb = path->nodes[level];
- rb_node = rb_simple_search(&cache->rb_root, eb->start);
- if (!rb_node) {
- upper = btrfs_backref_alloc_node(cache, eb->start,
- lower->level + 1);
- if (!upper) {
- btrfs_put_root(root);
- btrfs_backref_free_edge(cache, edge);
- ret = -ENOMEM;
- goto out;
- }
- upper->owner = btrfs_header_owner(eb);
- if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
- upper->cowonly = 1;
-
- /*
- * If we know the block isn't shared we can avoid
- * checking its backrefs.
- */
- if (btrfs_block_can_be_shared(root, eb))
- upper->checked = 0;
- else
- upper->checked = 1;
-
- /*
- * Add the block to pending list if we need to check its
- * backrefs, we only do this once while walking up a
- * tree as we will catch anything else later on.
- */
- if (!upper->checked && need_check) {
- need_check = false;
- list_add_tail(&edge->list[UPPER],
- &cache->pending_edge);
- } else {
- if (upper->checked)
- need_check = true;
- INIT_LIST_HEAD(&edge->list[UPPER]);
- }
- } else {
- upper = rb_entry(rb_node, struct btrfs_backref_node,
- rb_node);
- ASSERT(upper->checked);
- INIT_LIST_HEAD(&edge->list[UPPER]);
- if (!upper->owner)
- upper->owner = btrfs_header_owner(eb);
- }
- btrfs_backref_link_edge(edge, lower, upper, LINK_LOWER);
-
- if (rb_node) {
- btrfs_put_root(root);
- break;
- }
- lower = upper;
- upper = NULL;
- }
-out:
- btrfs_release_path(path);
- return ret;
-}
-
-static int handle_one_tree_block(struct btrfs_backref_cache *cache,
- struct btrfs_path *path,
- struct btrfs_backref_iter *iter,
- struct btrfs_key *node_key,
- struct btrfs_backref_node *cur)
-{
- struct btrfs_fs_info *fs_info = cache->fs_info;
- struct btrfs_backref_edge *edge;
- struct btrfs_backref_node *exist;
- int ret;
-
- ret = btrfs_backref_iter_start(iter, cur->bytenr);
- if (ret < 0)
- return ret;
- /*
- * We skip the first btrfs_tree_block_info, as we don't use the key
- * stored in it, but fetch it from the tree block
- */
- if (btrfs_backref_has_tree_block_info(iter)) {
- ret = btrfs_backref_iter_next(iter);
- if (ret < 0)
- goto out;
- /* No extra backref? This means the tree block is corrupted */
- if (ret > 0) {
- ret = -EUCLEAN;
- goto out;
- }
- }
- WARN_ON(cur->checked);
- if (!list_empty(&cur->upper)) {
- /*
- * the backref was added previously when processing
- * backref of type BTRFS_TREE_BLOCK_REF_KEY
- */
- ASSERT(list_is_singular(&cur->upper));
- edge = list_entry(cur->upper.next, struct btrfs_backref_edge,
- list[LOWER]);
- ASSERT(list_empty(&edge->list[UPPER]));
- exist = edge->node[UPPER];
- /*
- * add the upper level block to pending list if we need
- * check its backrefs
- */
- if (!exist->checked)
- list_add_tail(&edge->list[UPPER], &cache->pending_edge);
- } else {
- exist = NULL;
- }
-
- for (; ret == 0; ret = btrfs_backref_iter_next(iter)) {
- struct extent_buffer *eb;
- struct btrfs_key key;
- int type;
-
- cond_resched();
- eb = btrfs_backref_get_eb(iter);
-
- key.objectid = iter->bytenr;
- if (btrfs_backref_iter_is_inline_ref(iter)) {
- struct btrfs_extent_inline_ref *iref;
-
- /* update key for inline back ref */
- iref = (struct btrfs_extent_inline_ref *)
- ((unsigned long)iter->cur_ptr);
- type = btrfs_get_extent_inline_ref_type(eb, iref,
- BTRFS_REF_TYPE_BLOCK);
- if (type == BTRFS_REF_TYPE_INVALID) {
- ret = -EUCLEAN;
- goto out;
- }
- key.type = type;
- key.offset = btrfs_extent_inline_ref_offset(eb, iref);
- } else {
- key.type = iter->cur_key.type;
- key.offset = iter->cur_key.offset;
- }
-
- /*
- * Parent node found and matches current inline ref, no need to
- * rebuild this node for this inline ref.
- */
- if (exist &&
- ((key.type == BTRFS_TREE_BLOCK_REF_KEY &&
- exist->owner == key.offset) ||
- (key.type == BTRFS_SHARED_BLOCK_REF_KEY &&
- exist->bytenr == key.offset))) {
- exist = NULL;
- continue;
- }
-
- /* SHARED_BLOCK_REF means key.offset is the parent bytenr */
- if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
- ret = handle_direct_tree_backref(cache, &key, cur);
- if (ret < 0)
- goto out;
- continue;
- } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
- ret = -EINVAL;
- btrfs_print_v0_err(fs_info);
- btrfs_handle_fs_error(fs_info, ret, NULL);
- goto out;
- } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) {
- continue;
- }
-
- /*
- * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset
- * means the root objectid. We need to search the tree to get
- * its parent bytenr.
- */
- ret = handle_indirect_tree_backref(cache, path, &key, node_key,
- cur);
- if (ret < 0)
- goto out;
- }
- ret = 0;
- cur->checked = 1;
- WARN_ON(exist);
-out:
- btrfs_backref_iter_release(iter);
- return ret;
-}
-
-/*
* In handle_one_tree_backref(), we have only linked the lower node to the edge,
* but the upper node hasn't been linked to the edge.
* This means we can only iterate through btrfs_backref_node::upper to reach
@@ -969,7 +615,8 @@ static noinline_for_stack struct btrfs_backref_node *build_backref_tree(
/* Breadth-first search to build backref cache */
do {
- ret = handle_one_tree_block(cache, path, iter, node_key, cur);
+ ret = btrfs_backref_add_tree_node(cache, path, iter, node_key,
+ cur);
if (ret < 0) {
err = ret;
goto out;