fbdev: move FBIO_WAITFORVSYNC to linux/fb.h

[safe/jmp/linux-2.6] / include / linux / rmap.h

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 0b4913a..7721674 100644 (file)
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -26,6 +26,18 @@
  */
 struct anon_vma {
        spinlock_t lock;        /* Serialize access to vma list */
+#if defined(CONFIG_KSM) || defined(CONFIG_MIGRATION)
+
+       /*
+        * The external_refcount is taken by either KSM or page migration
+        * to take a reference to an anon_vma when there is no
+        * guarantee that the vma of page tables will exist for
+        * the duration of the operation. A caller that takes
+        * the reference is responsible for clearing up the
+        * anon_vma if they are the last user on release
+        */
+       atomic_t external_refcount;
+#endif
        /*
         * NOTE: the LSB of the head.next is set by
         * mm_take_all_locks() _after_ taking the above lock. So the
@@ -34,10 +46,50 @@ struct anon_vma {
         * 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 */
+       struct list_head head;  /* Chain of private "related" vmas */
+};
+
+/*
+ * The copy-on-write semantics of fork mean that an anon_vma
+ * can become associated with multiple processes. Furthermore,
+ * each child process will have its own anon_vma, where new
+ * pages for that process are instantiated.
+ *
+ * This structure allows us to find the anon_vmas associated
+ * with a VMA, or the VMAs associated with an anon_vma.
+ * The "same_vma" list contains the anon_vma_chains linking
+ * all the anon_vmas associated with this VMA.
+ * The "same_anon_vma" list contains the anon_vma_chains
+ * which link all the VMAs associated with this anon_vma.
+ */
+struct anon_vma_chain {
+       struct vm_area_struct *vma;
+       struct anon_vma *anon_vma;
+       struct list_head same_vma;   /* locked by mmap_sem & page_table_lock */
+       struct list_head same_anon_vma; /* locked by anon_vma->lock */
 };
 
 #ifdef CONFIG_MMU
+#if defined(CONFIG_KSM) || defined(CONFIG_MIGRATION)
+static inline void anonvma_external_refcount_init(struct anon_vma *anon_vma)
+{
+       atomic_set(&anon_vma->external_refcount, 0);
+}
+
+static inline int anonvma_external_refcount(struct anon_vma *anon_vma)
+{
+       return atomic_read(&anon_vma->external_refcount);
+}
+#else
+static inline void anonvma_external_refcount_init(struct anon_vma *anon_vma)
+{
+}
+
+static inline int anonvma_external_refcount(struct anon_vma *anon_vma)
+{
+       return 0;
+}
+#endif /* CONFIG_KSM */
 
 static inline struct anon_vma *page_anon_vma(struct page *page)
 {
@@ -66,14 +118,23 @@ static inline void anon_vma_unlock(struct vm_area_struct *vma)
  */
 void anon_vma_init(void);      /* create anon_vma_cachep */
 int  anon_vma_prepare(struct vm_area_struct *);
-void __anon_vma_merge(struct vm_area_struct *, struct vm_area_struct *);
-void anon_vma_unlink(struct vm_area_struct *);
-void anon_vma_link(struct vm_area_struct *);
+void unlink_anon_vmas(struct vm_area_struct *);
+int anon_vma_clone(struct vm_area_struct *, struct vm_area_struct *);
+int anon_vma_fork(struct vm_area_struct *, struct vm_area_struct *);
 void __anon_vma_link(struct vm_area_struct *);
+void anon_vma_free(struct anon_vma *);
+
+static inline void anon_vma_merge(struct vm_area_struct *vma,
+                                 struct vm_area_struct *next)
+{
+       VM_BUG_ON(vma->anon_vma != next->anon_vma);
+       unlink_anon_vmas(next);
+}
 
 /*
  * rmap interfaces called when adding or removing pte of page
  */
+void page_move_anon_rmap(struct page *, struct vm_area_struct *, unsigned long);
 void page_add_anon_rmap(struct page *, struct vm_area_struct *, unsigned long);
 void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long);
 void page_add_file_rmap(struct page *);
@@ -140,6 +201,12 @@ struct anon_vma *page_lock_anon_vma(struct page *page);
 void page_unlock_anon_vma(struct anon_vma *anon_vma);
 int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
 
+/*
+ * Called by migrate.c to remove migration ptes, but might be used more later.
+ */
+int rmap_walk(struct page *page, int (*rmap_one)(struct page *,
+               struct vm_area_struct *, unsigned long, void *), void *arg);
+
 #else  /* !CONFIG_MMU */
 
 #define anon_vma_init()                do {} while (0)
@@ -151,7 +218,7 @@ static inline int page_referenced(struct page *page, int is_locked,
                                  unsigned long *vm_flags)
 {
        *vm_flags = 0;
-       return TestClearPageReferenced(page);
+       return 0;
 }
 
 #define try_to_unmap(page, refs) SWAP_FAIL