[PATCH v12 03/29] mmu_notifier: pass page pointer to mmu_notifier_invalidate_page() v2

["Jérôme Glisse" <jglisse@redhat.com>]

Listener of mm event might not have easy way to get the struct page
behind an address invalidated with mmu_notifier_invalidate_page()
function as this happens after the cpu page table have been clear/
updated. This happens for instance if the listener is storing a dma
mapping inside its secondary page table. To avoid complex reverse
dma mapping lookup just pass along a pointer to the page being
invalidated.

Changed since v1:
  - English syntax fixes.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
---
 drivers/infiniband/core/umem_odp.c | 1 +
 drivers/iommu/amd_iommu_v2.c       | 1 +
 drivers/misc/sgi-gru/grutlbpurge.c | 1 +
 drivers/xen/gntdev.c               | 1 +
 include/linux/mmu_notifier.h       | 6 +++++-
 mm/mmu_notifier.c                  | 3 ++-
 mm/rmap.c                          | 4 ++--
 virt/kvm/kvm_main.c                | 1 +
 8 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index 58d9a00..0541761 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -166,6 +166,7 @@ static int invalidate_page_trampoline(struct ib_umem *item, u64 start,
 static void ib_umem_notifier_invalidate_page(struct mmu_notifier *mn,
 					     struct mm_struct *mm,
 					     unsigned long address,
+					     struct page *page,
 					     enum mmu_event event)
 {
 	struct ib_ucontext *context = container_of(mn, struct ib_ucontext, mn);
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index 2b4be22..bb5c678 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -393,6 +393,7 @@ static int mn_clear_flush_young(struct mmu_notifier *mn,
 static void mn_invalidate_page(struct mmu_notifier *mn,
 			       struct mm_struct *mm,
 			       unsigned long address,
+			       struct page *page,
 			       enum mmu_event event)
 {
 	__mn_flush_page(mn, address);
diff --git a/drivers/misc/sgi-gru/grutlbpurge.c b/drivers/misc/sgi-gru/grutlbpurge.c
index 40cf589..4268649 100644
--- a/drivers/misc/sgi-gru/grutlbpurge.c
+++ b/drivers/misc/sgi-gru/grutlbpurge.c
@@ -250,6 +250,7 @@ static void gru_invalidate_range_end(struct mmu_notifier *mn,
 
 static void gru_invalidate_page(struct mmu_notifier *mn, struct mm_struct *mm,
 				unsigned long address,
+				struct page *page,
 				enum mmu_event event)
 {
 	struct gru_mm_struct *gms = container_of(mn, struct gru_mm_struct,
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 0ca3720..c318aff 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -485,6 +485,7 @@ static void mn_invl_range_start(struct mmu_notifier *mn,
 static void mn_invl_page(struct mmu_notifier *mn,
 			 struct mm_struct *mm,
 			 unsigned long address,
+			 struct page *page,
 			 enum mmu_event event)
 {
 	struct mmu_notifier_range range;
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index c4ba044..9e65a3f 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -184,6 +184,7 @@ struct mmu_notifier_ops {
 	void (*invalidate_page)(struct mmu_notifier *mn,
 				struct mm_struct *mm,
 				unsigned long address,
+				struct page *page,
 				enum mmu_event event);
 
 	/*
@@ -305,6 +306,7 @@ extern void __mmu_notifier_change_pte(struct mm_struct *mm,
 				      enum mmu_event event);
 extern void __mmu_notifier_invalidate_page(struct mm_struct *mm,
 					  unsigned long address,
+					  struct page *page,
 					  enum mmu_event event);
 extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm,
 					struct mmu_notifier_range *range);
@@ -362,10 +364,11 @@ static inline void mmu_notifier_change_pte(struct mm_struct *mm,
 
 static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
 						unsigned long address,
+						struct page *page,
 						enum mmu_event event)
 {
 	if (mm_has_notifiers(mm))
-		__mmu_notifier_invalidate_page(mm, address, event);
+		__mmu_notifier_invalidate_page(mm, address, page, event);
 }
 
 static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm,
@@ -538,6 +541,7 @@ static inline void mmu_notifier_change_pte(struct mm_struct *mm,
 
 static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
 						unsigned long address,
+						struct page *page,
 						enum mmu_event event)
 {
 }
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index c43c851..316e4a9 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -177,6 +177,7 @@ void __mmu_notifier_change_pte(struct mm_struct *mm,
 
 void __mmu_notifier_invalidate_page(struct mm_struct *mm,
 				    unsigned long address,
+				    struct page *page,
 				    enum mmu_event event)
 {
 	struct mmu_notifier *mn;
@@ -185,7 +186,7 @@ void __mmu_notifier_invalidate_page(struct mm_struct *mm,
 	id = srcu_read_lock(&srcu);
 	hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
 		if (mn->ops->invalidate_page)
-			mn->ops->invalidate_page(mn, mm, address, event);
+			mn->ops->invalidate_page(mn, mm, address, page, event);
 	}
 	srcu_read_unlock(&srcu, id);
 }
diff --git a/mm/rmap.c b/mm/rmap.c
index a24d0b2..063f8de 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1054,7 +1054,7 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma,
 	pte_unmap_unlock(pte, ptl);
 
 	if (ret) {
-		mmu_notifier_invalidate_page(mm, address, MMU_WRITE_BACK);
+		mmu_notifier_invalidate_page(mm, address, page, MMU_WRITE_BACK);
 		(*cleaned)++;
 	}
 out:
@@ -1552,7 +1552,7 @@ discard:
 out_unmap:
 	pte_unmap_unlock(pte, ptl);
 	if (ret != SWAP_FAIL && ret != SWAP_MLOCK && !(flags & TTU_MUNLOCK))
-		mmu_notifier_invalidate_page(mm, address, MMU_MIGRATE);
+		mmu_notifier_invalidate_page(mm, address, page, MMU_MIGRATE);
 out:
 	return ret;
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b059307..d6dbaab 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -273,6 +273,7 @@ static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
 					     struct mm_struct *mm,
 					     unsigned long address,
+					     struct page *page,
 					     enum mmu_event event)
 {
 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
-- 
2.4.3