---

yaml
---
r: 164399
b: refs/heads/master
c: 828502d
h: refs/heads/master
i:
  164397: 98e9d91
  164395: fe43ddc
  164391: c38f9cb
  164383: b364ffd
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 451ea25da71590361c71bf3044c55b870a887d53
+refs/heads/master: 828502d30073036a486d96b1fe051e0f08b6df83

trunk/include/linux/mmu_notifier.h

@@ -61,6 +61,15 @@ struct mmu_notifier_ops {
 				 struct mm_struct *mm,
 				 unsigned long address);
 
+	/*
+	 * change_pte is called in cases that pte mapping to page is changed:
+	 * for example, when ksm remaps pte to point to a new shared page.
+	 */
+	void (*change_pte)(struct mmu_notifier *mn,
+			   struct mm_struct *mm,
+			   unsigned long address,
+			   pte_t pte);
+
 	/*
 	 * Before this is invoked any secondary MMU is still ok to
 	 * read/write to the page previously pointed to by the Linux
@@ -154,6 +163,8 @@ extern void __mmu_notifier_mm_destroy(struct mm_struct *mm);
 extern void __mmu_notifier_release(struct mm_struct *mm);
 extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm,
 					  unsigned long address);
+extern void __mmu_notifier_change_pte(struct mm_struct *mm,
+				      unsigned long address, pte_t pte);
 extern void __mmu_notifier_invalidate_page(struct mm_struct *mm,
 					  unsigned long address);
 extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm,
@@ -175,6 +186,13 @@ static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
 	return 0;
 }
 
+static inline void mmu_notifier_change_pte(struct mm_struct *mm,
+					   unsigned long address, pte_t pte)
+{
+	if (mm_has_notifiers(mm))
+		__mmu_notifier_change_pte(mm, address, pte);
+}
+
 static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
 					  unsigned long address)
 {
@@ -236,6 +254,16 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
 	__young;							\
 })
 
+#define set_pte_at_notify(__mm, __address, __ptep, __pte)		\
+({									\
+	struct mm_struct *___mm = __mm;					\
+	unsigned long ___address = __address;				\
+	pte_t ___pte = __pte;						\
+									\
+	set_pte_at(___mm, ___address, __ptep, ___pte);			\
+	mmu_notifier_change_pte(___mm, ___address, ___pte);		\
+})
+
 #else /* CONFIG_MMU_NOTIFIER */
 
 static inline void mmu_notifier_release(struct mm_struct *mm)
@@ -248,6 +276,11 @@ static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm,
 	return 0;
 }
 
+static inline void mmu_notifier_change_pte(struct mm_struct *mm,
+					   unsigned long address, pte_t pte)
+{
+}
+
 static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
 					  unsigned long address)
 {
@@ -273,6 +306,7 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
 
 #define ptep_clear_flush_young_notify ptep_clear_flush_young
 #define ptep_clear_flush_notify ptep_clear_flush
+#define set_pte_at_notify set_pte_at
 
 #endif /* CONFIG_MMU_NOTIFIER */
 

trunk/mm/memory.c

@@ -2115,9 +2115,14 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		 * seen in the presence of one thread doing SMC and another
 		 * thread doing COW.
 		 */
-		ptep_clear_flush_notify(vma, address, page_table);
+		ptep_clear_flush(vma, address, page_table);
 		page_add_new_anon_rmap(new_page, vma, address);
-		set_pte_at(mm, address, page_table, entry);
+		/*
+		 * We call the notify macro here because, when using secondary
+		 * mmu page tables (such as kvm shadow page tables), we want the
+		 * new page to be mapped directly into the secondary page table.
+		 */
+		set_pte_at_notify(mm, address, page_table, entry);
 		update_mmu_cache(vma, address, entry);
 		if (old_page) {
 			/*

trunk/mm/mmu_notifier.c

@@ -99,6 +99,26 @@ int __mmu_notifier_clear_flush_young(struct mm_struct *mm,
 	return young;
 }
 
+void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address,
+			       pte_t pte)
+{
+	struct mmu_notifier *mn;
+	struct hlist_node *n;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(mn, n, &mm->mmu_notifier_mm->list, hlist) {
+		if (mn->ops->change_pte)
+			mn->ops->change_pte(mn, mm, address, pte);
+		/*
+		 * Some drivers don't have change_pte,
+		 * so we must call invalidate_page in that case.
+		 */
+		else if (mn->ops->invalidate_page)
+			mn->ops->invalidate_page(mn, mm, address);
+	}
+	rcu_read_unlock();
+}
+
 void __mmu_notifier_invalidate_page(struct mm_struct *mm,
 					  unsigned long address)
 {