/* * 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/export.h> #include <linux/list.h> #include <linux/bug.h> #include <linux/kernel.h> #include <linux/rculist.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); WARN(new == prev || new == next, "list_add double add: new=%p, prev=%p, next=%p.\n", new, prev, next); 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); /* * RCU variants. */ void __list_add_rcu(struct list_head *new, struct list_head *prev, struct list_head *next) { WARN(next->prev != prev, "list_add_rcu corruption. next->prev should be " "prev (%p), but was %p. (next=%p).\n", prev, next->prev, next); WARN(prev->next != next, "list_add_rcu corruption. prev->next should be " "next (%p), but was %p. (prev=%p).\n", next, prev->next, prev); new->next = next; new->prev = prev; rcu_assign_pointer(list_next_rcu(prev), new); next->prev = new; } EXPORT_SYMBOL(__list_add_rcu);