list_debug.c 1.6 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364
  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. #include <linux/module.h>
  9. #include <linux/list.h>
  10. /*
  11. * Insert a new entry between two known consecutive entries.
  12. *
  13. * This is only for internal list manipulation where we know
  14. * the prev/next entries already!
  15. */
  16. void __list_add(struct list_head *new,
  17. struct list_head *prev,
  18. struct list_head *next)
  19. {
  20. if (unlikely(next->prev != prev)) {
  21. printk(KERN_ERR "list_add corruption. next->prev should be "
  22. "prev (%p), but was %p. (next=%p).\n",
  23. prev, next->prev, next);
  24. BUG();
  25. }
  26. if (unlikely(prev->next != next)) {
  27. printk(KERN_ERR "list_add corruption. prev->next should be "
  28. "next (%p), but was %p. (prev=%p).\n",
  29. next, prev->next, prev);
  30. BUG();
  31. }
  32. next->prev = new;
  33. new->next = next;
  34. new->prev = prev;
  35. prev->next = new;
  36. }
  37. EXPORT_SYMBOL(__list_add);
  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. if (unlikely(entry->prev->next != entry)) {
  47. printk(KERN_ERR "list_del corruption. prev->next should be %p, "
  48. "but was %p\n", entry, entry->prev->next);
  49. BUG();
  50. }
  51. if (unlikely(entry->next->prev != entry)) {
  52. printk(KERN_ERR "list_del corruption. next->prev should be %p, "
  53. "but was %p\n", entry, entry->next->prev);
  54. BUG();
  55. }
  56. __list_del(entry->prev, entry->next);
  57. entry->next = LIST_POISON1;
  58. entry->prev = LIST_POISON2;
  59. }
  60. EXPORT_SYMBOL(list_del);