zfs-builds-mm/zfs-2.0.0-rc6/module/zfs/objlist.c
2020-11-15 11:35:49 +01:00

84 lines
2.6 KiB
C

/*
* CDDL HEADER START
*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2018 by Delphix. All rights reserved.
*/
#include <sys/objlist.h>
#include <sys/zfs_context.h>
objlist_t *
objlist_create(void)
{
objlist_t *list = kmem_alloc(sizeof (*list), KM_SLEEP);
list_create(&list->ol_list, sizeof (objlist_node_t),
offsetof(objlist_node_t, on_node));
list->ol_last_lookup = 0;
return (list);
}
void
objlist_destroy(objlist_t *list)
{
for (objlist_node_t *n = list_remove_head(&list->ol_list);
n != NULL; n = list_remove_head(&list->ol_list)) {
kmem_free(n, sizeof (*n));
}
list_destroy(&list->ol_list);
kmem_free(list, sizeof (*list));
}
/*
* This function looks through the objlist to see if the specified object number
* is contained in the objlist. In the process, it will remove all object
* numbers in the list that are smaller than the specified object number. Thus,
* any lookup of an object number smaller than a previously looked up object
* number will always return false; therefore, all lookups should be done in
* ascending order.
*/
boolean_t
objlist_exists(objlist_t *list, uint64_t object)
{
objlist_node_t *node = list_head(&list->ol_list);
ASSERT3U(object, >=, list->ol_last_lookup);
list->ol_last_lookup = object;
while (node != NULL && node->on_object < object) {
VERIFY3P(node, ==, list_remove_head(&list->ol_list));
kmem_free(node, sizeof (*node));
node = list_head(&list->ol_list);
}
return (node != NULL && node->on_object == object);
}
/*
* The objlist is a list of object numbers stored in ascending order. However,
* the insertion of new object numbers does not seek out the correct location to
* store a new object number; instead, it appends it to the list for simplicity.
* Thus, any users must take care to only insert new object numbers in ascending
* order.
*/
void
objlist_insert(objlist_t *list, uint64_t object)
{
objlist_node_t *node = kmem_zalloc(sizeof (*node), KM_SLEEP);
node->on_object = object;
#ifdef ZFS_DEBUG
objlist_node_t *last_object = list_tail(&list->ol_list);
uint64_t last_objnum = (last_object != NULL ? last_object->on_object :
0);
ASSERT3U(node->on_object, >, last_objnum);
#endif
list_insert_tail(&list->ol_list, node);
}