1 files changed, 37 insertions, 4 deletions

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 77216742c178..31b2fd75dcba 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -26,6 +26,7 @@
  */
 struct anon_vma {
         spinlock_t lock;        /* Serialize access to vma list */
+        struct anon_vma *root;  /* Root of this anon_vma tree */
 #if defined(CONFIG_KSM) || defined(CONFIG_MIGRATION)
 
         /*
@@ -80,6 +81,13 @@ static inline int anonvma_external_refcount(struct anon_vma *anon_vma)
 {
         return atomic_read(&anon_vma->external_refcount);
 }
+
+static inline void get_anon_vma(struct anon_vma *anon_vma)
+{
+        atomic_inc(&anon_vma->external_refcount);
+}
+
+void drop_anon_vma(struct anon_vma *);
 #else
 static inline void anonvma_external_refcount_init(struct anon_vma *anon_vma)
 {
@@ -89,6 +97,14 @@ static inline int anonvma_external_refcount(struct anon_vma *anon_vma)
 {
         return 0;
 }
+
+static inline void get_anon_vma(struct anon_vma *anon_vma)
+{
+}
+
+static inline void drop_anon_vma(struct anon_vma *anon_vma)
+{
+}
 #endif /* CONFIG_KSM */
 
 static inline struct anon_vma *page_anon_vma(struct page *page)
@@ -99,18 +115,28 @@ static inline struct anon_vma *page_anon_vma(struct page *page)
         return page_rmapping(page);
 }
 
-static inline void anon_vma_lock(struct vm_area_struct *vma)
+static inline void vma_lock_anon_vma(struct vm_area_struct *vma)
 {
         struct anon_vma *anon_vma = vma->anon_vma;
         if (anon_vma)
-                spin_lock(&anon_vma->lock);
+                spin_lock(&anon_vma->root->lock);
 }
 
-static inline void anon_vma_unlock(struct vm_area_struct *vma)
+static inline void vma_unlock_anon_vma(struct vm_area_struct *vma)
 {
         struct anon_vma *anon_vma = vma->anon_vma;
         if (anon_vma)
-                spin_unlock(&anon_vma->lock);
+                spin_unlock(&anon_vma->root->lock);
+}
+
+static inline void anon_vma_lock(struct anon_vma *anon_vma)
+{
+        spin_lock(&anon_vma->root->lock);
+}
+
+static inline void anon_vma_unlock(struct anon_vma *anon_vma)
+{
+        spin_unlock(&anon_vma->root->lock);
 }
 
 /*
@@ -136,10 +162,17 @@ static inline void anon_vma_merge(struct vm_area_struct *vma,
  */
 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 do_page_add_anon_rmap(struct page *, struct vm_area_struct *,
+                           unsigned long, int);
 void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long);
 void page_add_file_rmap(struct page *);
 void page_remove_rmap(struct page *);
 
+void hugepage_add_anon_rmap(struct page *, struct vm_area_struct *,
+                            unsigned long);
+void hugepage_add_new_anon_rmap(struct page *, struct vm_area_struct *,
+                                unsigned long);
+
 static inline void page_dup_rmap(struct page *page)
 {
         atomic_inc(&page->_mapcount);