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 { 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); 31 next->prev = new; 32 new->next = next; 33 new->prev = prev; 34 prev->next = new; 35 } 36 EXPORT_SYMBOL(__list_add); 37 38 /** 39 * list_del - deletes entry from list. 40 * @entry: the element to delete from the list. 41 * Note: list_empty on entry does not return true after this, the entry is 42 * in an undefined state. 43 */ 44 void list_del(struct list_head *entry) 45 { 46 WARN(entry->next == LIST_POISON1, 47 "list_del corruption, next is LIST_POISON1 (%p)\n", 48 LIST_POISON1); 49 WARN(entry->next != LIST_POISON1 && entry->prev == LIST_POISON2, 50 "list_del corruption, prev is LIST_POISON2 (%p)\n", 51 LIST_POISON2); 52 WARN(entry->prev->next != entry, 53 "list_del corruption. prev->next should be %p, " 54 "but was %p\n", entry, entry->prev->next); 55 WARN(entry->next->prev != entry, 56 "list_del corruption. next->prev should be %p, " 57 "but was %p\n", entry, entry->next->prev); 58 __list_del(entry->prev, entry->next); 59 entry->next = LIST_POISON1; 60 entry->prev = LIST_POISON2; 61 } 62 EXPORT_SYMBOL(list_del); 63