Function ddt_lookup

freebsd/contrib/openzfs/module/zfs/ddt.c:669–730

}

ddt_entry_t *
ddt_lookup(ddt_t *ddt, const blkptr_t *bp, boolean_t add)
{
	ddt_entry_t *dde, dde_search;
	enum ddt_type type;
	enum ddt_class class;
	avl_index_t where;
	int error;

	ASSERT(MUTEX_HELD(&ddt->ddt_lock));

	ddt_key_fill(&dde_search.dde_key, bp);

	dde = avl_find(&ddt->ddt_tree, &dde_search, &where);
	if (dde == NULL) {
		if (!add)
			return (NULL);
		dde = ddt_alloc(&dde_search.dde_key);
		avl_insert(&ddt->ddt_tree, dde, where);
	}

	while (dde->dde_loading)
		cv_wait(&dde->dde_cv, &ddt->ddt_lock);

	if (dde->dde_loaded)
		return (dde);

	dde->dde_loading = B_TRUE;

	ddt_exit(ddt);

	error = ENOENT;

	for (type = 0; type < DDT_TYPES; type++) {
		for (class = 0; class < DDT_CLASSES; class++) {
			error = ddt_object_lookup(ddt, type, class, dde);
			if (error != ENOENT) {
				ASSERT0(error);
				break;
			}
		}
		if (error != ENOENT)
			break;
	}

	ddt_enter(ddt);

	ASSERT(dde->dde_loaded == B_FALSE);
	ASSERT(dde->dde_loading == B_TRUE);

	dde->dde_type = type;	/* will be DDT_TYPES if no entry found */
	dde->dde_class = class;	/* will be DDT_CLASSES if no entry found */
	dde->dde_loaded = B_TRUE;
	dde->dde_loading = B_FALSE;

	if (error == 0)
		ddt_stat_update(ddt, dde, -1ULL);