Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[linux-2.6-omap-h63xx.git] / include / linux / rmap.h

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 1383692ac5bd8c8dc5c06498a38795a256f56c93..fed6f5e0b41139070dd9c99b84ee324e7254f63f 100644 (file)
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -26,6 +26,14 @@
  */
 struct anon_vma {
        spinlock_t lock;        /* Serialize access to vma list */
+       /*
+        * NOTE: the LSB of the head.next is set by
+        * mm_take_all_locks() _after_ taking the above lock. So the
+        * head must only be read/written after taking the above lock
+        * to be sure to see a valid next pointer. The LSB bit itself
+        * is serialized by a system wide lock only visible to
+        * mm_take_all_locks() (mm_all_locks_mutex).
+        */
        struct list_head head;  /* List of private "related" vmas */
 };
 
@@ -94,7 +102,7 @@ int try_to_unmap(struct page *, int ignore_refs);
  * Called from mm/filemap_xip.c to unmap empty zero page
  */
 pte_t *page_check_address(struct page *, struct mm_struct *,
-                               unsigned long, spinlock_t **);
+                               unsigned long, spinlock_t **, int);
 
 /*
  * Used by swapoff to help locate where page is expected in vma.