fs/btrfs/delayed-ref.c

57  * Release a ref head's reservation.
63  * Drops the delayed ref head's count from the delayed refs rsv and free any
383 /* insert a new ref to head ref rbtree */
463  * Find a head entry based on bytenr. This returns the delayed ref head if it
501 			   struct btrfs_delayed_ref_head *head)
504 	if (mutex_trylock(&head->mutex))
507 	refcount_inc(&head->refs);
510 	mutex_lock(&head->mutex);
512 	if (RB_EMPTY_NODE(&head->href_node)) {
513 		mutex_unlock(&head->mutex);
514 		btrfs_put_delayed_ref_head(head);
517 	btrfs_put_delayed_ref_head(head);
523 				    struct btrfs_delayed_ref_head *head,
526 	lockdep_assert_held(&head->lock);
527 	rb_erase_cached(&ref->ref_node, &head->ref_tree);
538 		      struct btrfs_delayed_ref_head *head,
566 		drop_delayed_ref(fs_info, delayed_refs, head, next);
569 			drop_delayed_ref(fs_info, delayed_refs, head, ref);
585 			      struct btrfs_delayed_ref_head *head)
591 	lockdep_assert_held(&head->lock);
593 	if (RB_EMPTY_ROOT(&head->ref_tree.rb_root))
597 	if (head->is_data)
602 	for (node = rb_first_cached(&head->ref_tree); node;
607 		if (merge_ref(fs_info, delayed_refs, head, ref, seq))
630 	struct btrfs_delayed_ref_head *head;
634 	head = find_ref_head(delayed_refs, delayed_refs->run_delayed_start,
636 	if (!head && delayed_refs->run_delayed_start != 0) {
638 		head = find_first_ref_head(delayed_refs);
640 	if (!head)
643 	while (head->processing) {
646 		node = rb_next(&head->href_node);
653 		head = rb_entry(node, struct btrfs_delayed_ref_head,
657 	head->processing = true;
660 	delayed_refs->run_delayed_start = head->bytenr +
661 		head->num_bytes;
662 	return head;
666 			   struct btrfs_delayed_ref_head *head)
669 	lockdep_assert_held(&head->lock);
671 	rb_erase_cached(&head->href_node, &delayed_refs->href_root);
672 	RB_CLEAR_NODE(&head->href_node);
675 	if (!head->processing)
736  * helper function to update the accounting in the head ref
764 		 * with an existing head ref without
798 	 * update the reference mod on the head to reflect this new operation,
809 	 * We reserve bytes for csum deletion when adding or updating a ref head
848 		 * The head node stores the sum of all the mods, so dropping a ref
849 		 * should drop the sum in the head node by one.
899  * helper function to actually insert a head node into the rbtree.
939 		 * adding the ref head and not when adding individual drop refs
1120 	 * insert both the head node and the new ref without dropping
1211 	 * insert both the head node and the new ref without dropping
1289  * This does a simple search for the head node for a given extent.  Returns the
1290  * head node if found, or NULL if not.