[linux.git] / lib / list_debug.c

/*
 * Copyright 2006, Red Hat, Inc., Dave Jones
 * Released under the General Public License (GPL).
 *
 * This file contains the linked list implementations for
 * DEBUG_LIST.
 */

#include <linux/module.h>
#include <linux/list.h>

/*
 * Insert a new entry between two known consecutive entries.
 *
 * This is only for internal list manipulation where we know
 * the prev/next entries already!
 */

void __list_add(struct list_head *new,
			      struct list_head *prev,
			      struct list_head *next)
{
	WARN(next->prev != prev,
		"list_add corruption. next->prev should be "
		"prev (%p), but was %p. (next=%p).\n",
		prev, next->prev, next);
	WARN(prev->next != next,
		"list_add corruption. prev->next should be "
		"next (%p), but was %p. (prev=%p).\n",
		next, prev->next, prev);
	next->prev = new;
	new->next = next;
	new->prev = prev;
	prev->next = new;
}
EXPORT_SYMBOL(__list_add);

void __list_del_entry(struct list_head *entry)
{
	struct list_head *prev, *next;

	prev = entry->prev;
	next = entry->next;

	if (WARN(next == LIST_POISON1,
		"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
		entry, LIST_POISON1) ||
	    WARN(prev == LIST_POISON2,
		"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
		entry, LIST_POISON2) ||
	    WARN(prev->next != entry,
		"list_del corruption. prev->next should be %p, "
		"but was %p\n", entry, prev->next) ||
	    WARN(next->prev != entry,
		"list_del corruption. next->prev should be %p, "
		"but was %p\n", entry, next->prev))
		return;

	__list_del(prev, next);
}
EXPORT_SYMBOL(__list_del_entry);

/**
 * list_del - deletes entry from list.
 * @entry: the element to delete from the list.
 * Note: list_empty on entry does not return true after this, the entry is
 * in an undefined state.
 */
void list_del(struct list_head *entry)
{
	__list_del_entry(entry);
	entry->next = LIST_POISON1;
	entry->prev = LIST_POISON2;
}
EXPORT_SYMBOL(list_del);
Commit	Line	Data
199a9afc DJ	1	/*
	2	* Copyright 2006, Red Hat, Inc., Dave Jones
	3	* Released under the General Public License (GPL).
	4	*
	5	* This file contains the linked list implementations for
	6	* DEBUG_LIST.
	7	*/
	8
	9	#include <linux/module.h>
	10	#include <linux/list.h>
	11
	12	/*
	13	* Insert a new entry between two known consecutive entries.
	14	*
	15	* This is only for internal list manipulation where we know
	16	* the prev/next entries already!
	17	*/
	18
	19	void __list_add(struct list_head *new,
	20	struct list_head *prev,
	21	struct list_head *next)
	22	{
924d9add DJ	23	WARN(next->prev != prev,
	24	"list_add corruption. next->prev should be "
	25	"prev (%p), but was %p. (next=%p).\n",
	26	prev, next->prev, next);
	27	WARN(prev->next != next,
	28	"list_add corruption. prev->next should be "
	29	"next (%p), but was %p. (prev=%p).\n",
	30	next, prev->next, prev);
199a9afc DJ	31	next->prev = new;
	32	new->next = next;
	33	new->prev = prev;
	34	prev->next = new;
	35	}
	36	EXPORT_SYMBOL(__list_add);
	37
3c18d4de LT	38	void __list_del_entry(struct list_head *entry)
	39	{
	40	struct list_head prev, next;
	41
	42	prev = entry->prev;
	43	next = entry->next;
	44
	45	if (WARN(next == LIST_POISON1,
	46	"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
	47	entry, LIST_POISON1) \|\|
	48	WARN(prev == LIST_POISON2,
	49	"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
	50	entry, LIST_POISON2) \|\|
	51	WARN(prev->next != entry,
	52	"list_del corruption. prev->next should be %p, "
	53	"but was %p\n", entry, prev->next) \|\|
	54	WARN(next->prev != entry,
	55	"list_del corruption. next->prev should be %p, "
	56	"but was %p\n", entry, next->prev))
	57	return;
	58
	59	__list_del(prev, next);
	60	}
	61	EXPORT_SYMBOL(__list_del_entry);
	62
199a9afc DJ	63	/**
	64	* list_del - deletes entry from list.
	65	* @entry: the element to delete from the list.
	66	* Note: list_empty on entry does not return true after this, the entry is
	67	* in an undefined state.
	68	*/
	69	void list_del(struct list_head *entry)
	70	{
3c18d4de	71	__list_del_entry(entry);
199a9afc DJ	72	entry->next = LIST_POISON1;
	73	entry->prev = LIST_POISON2;
	74	}
	75	EXPORT_SYMBOL(list_del);