diff options
Diffstat (limited to 'lib/list_debug.c')
-rw-r--r-- | lib/list_debug.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/lib/list_debug.c b/lib/list_debug.c new file mode 100644 index 0000000..7ba9d82 --- /dev/null +++ b/lib/list_debug.c @@ -0,0 +1,76 @@ +/* + * 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) +{ + if (unlikely(next->prev != prev)) { + printk(KERN_ERR "list_add corruption. next->prev should be %p, but was %p\n", + prev, next->prev); + BUG(); + } + if (unlikely(prev->next != next)) { + printk(KERN_ERR "list_add corruption. prev->next should be %p, but was %p\n", + next, prev->next); + BUG(); + } + next->prev = new; + new->next = next; + new->prev = prev; + prev->next = new; +} +EXPORT_SYMBOL(__list_add); + +/** + * list_add - add a new entry + * @new: new entry to be added + * @head: list head to add it after + * + * Insert a new entry after the specified head. + * This is good for implementing stacks. + */ +void list_add(struct list_head *new, struct list_head *head) +{ + __list_add(new, head, head->next); +} +EXPORT_SYMBOL(list_add); + +/** + * 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) +{ + if (unlikely(entry->prev->next != entry)) { + printk(KERN_ERR "list_del corruption. prev->next should be %p, " + "but was %p\n", entry, entry->prev->next); + BUG(); + } + if (unlikely(entry->next->prev != entry)) { + printk(KERN_ERR "list_del corruption. next->prev should be %p, " + "but was %p\n", entry, entry->next->prev); + BUG(); + } + __list_del(entry->prev, entry->next); + entry->next = LIST_POISON1; + entry->prev = LIST_POISON2; +} +EXPORT_SYMBOL(list_del); |