1 files changed, 12 insertions, 48 deletions

diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index 1d1b1e13f79f..bc823c4c028b 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -4,6 +4,7 @@
 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <linux/mm_types.h>
+#include <linux/srcu.h>
 
 struct mmu_notifier;
 struct mmu_notifier_ops;
@@ -245,50 +246,6 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
                 __mmu_notifier_mm_destroy(mm);
 }
 
-/*
- * These two macros will sometime replace ptep_clear_flush.
- * ptep_clear_flush is implemented as macro itself, so this also is
- * implemented as a macro until ptep_clear_flush will converted to an
- * inline function, to diminish the risk of compilation failure. The
- * invalidate_page method over time can be moved outside the PT lock
- * and these two macros can be later removed.
- */
-#define ptep_clear_flush_notify(__vma, __address, __ptep)               \
-({                                                                      \
-        pte_t __pte;                                                    \
-        struct vm_area_struct *___vma = __vma;                          \
-        unsigned long ___address = __address;                           \
-        __pte = ptep_clear_flush(___vma, ___address, __ptep);           \
-        mmu_notifier_invalidate_page(___vma->vm_mm, ___address);        \
-        __pte;                                                          \
-})
-
-#define pmdp_clear_flush_notify(__vma, __address, __pmdp)               \
-({                                                                      \
-        pmd_t __pmd;                                                    \
-        struct vm_area_struct *___vma = __vma;                          \
-        unsigned long ___address = __address;                           \
-        VM_BUG_ON(__address & ~HPAGE_PMD_MASK);                         \
-        mmu_notifier_invalidate_range_start(___vma->vm_mm, ___address,  \
-                                            (__address)+HPAGE_PMD_SIZE);\
-        __pmd = pmdp_clear_flush(___vma, ___address, __pmdp);           \
-        mmu_notifier_invalidate_range_end(___vma->vm_mm, ___address,    \
-                                          (__address)+HPAGE_PMD_SIZE);  \
-        __pmd;                                                          \
-})
-
-#define pmdp_splitting_flush_notify(__vma, __address, __pmdp)           \
-({                                                                      \
-        struct vm_area_struct *___vma = __vma;                          \
-        unsigned long ___address = __address;                           \
-        VM_BUG_ON(__address & ~HPAGE_PMD_MASK);                         \
-        mmu_notifier_invalidate_range_start(___vma->vm_mm, ___address,  \
-                                            (__address)+HPAGE_PMD_SIZE);\
-        pmdp_splitting_flush(___vma, ___address, __pmdp);               \
-        mmu_notifier_invalidate_range_end(___vma->vm_mm, ___address,    \
-                                          (__address)+HPAGE_PMD_SIZE);  \
-})
-
 #define ptep_clear_flush_young_notify(__vma, __address, __ptep)         \
 ({                                                                      \
         int __young;                                                    \
@@ -311,14 +268,24 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
         __young;                                                        \
 })
 
+/*
+ * set_pte_at_notify() sets the pte _after_ running the notifier.
+ * This is safe to start by updating the secondary MMUs, because the primary MMU
+ * pte invalidate must have already happened with a ptep_clear_flush() before
+ * set_pte_at_notify() has been invoked.  Updating the secondary MMUs first is
+ * required when we change both the protection of the mapping from read-only to
+ * read-write and the pfn (like during copy on write page faults). Otherwise the
+ * old page would remain mapped readonly in the secondary MMUs after the new
+ * page is already writable by some CPU through the primary MMU.
+ */
 #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);             \
+        set_pte_at(___mm, ___address, __ptep, ___pte);                  \
 })
 
 #else /* CONFIG_MMU_NOTIFIER */
@@ -369,9 +336,6 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
 
 #define ptep_clear_flush_young_notify ptep_clear_flush_young
 #define pmdp_clear_flush_young_notify pmdp_clear_flush_young
-#define ptep_clear_flush_notify ptep_clear_flush
-#define pmdp_clear_flush_notify pmdp_clear_flush
-#define pmdp_splitting_flush_notify pmdp_splitting_flush
 #define set_pte_at_notify set_pte_at
 
 #endif /* CONFIG_MMU_NOTIFIER */