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authorJérôme Glisse <jglisse@redhat.com>2013-08-02 15:17:24 -0400
committerJérôme Glisse <jglisse@redhat.com>2016-04-07 13:23:23 -0400
commit6abff77f76d50c374057228baa0e01354d9bf1a1 (patch)
treed776cb91d9f79758431858ced7020301a28b9d0e
parent5692a25511e0da564d0f5a554ac9f39197b2358f (diff)
mmu_notifier: add event information to address invalidation v9
The event information will be useful for new user of mmu_notifier API. The event argument differentiate between a vma disappearing, a page being write protected or simply a page being unmaped. This allow new user to take different path for different event for instance on unmap the resource used to track a vma are still valid and should stay around. While if the event is saying that a vma is being destroy it means that any resources used to track this vma can be free. Changed since v1: - renamed action into event (updated commit message too). - simplified the event names and clarified their usage also documenting what exceptation the listener can have in respect to each event. Changed since v2: - Avoid crazy name. - Do not move code that do not need to move. Changed since v3: - Separate huge page split from mlock/munlock and softdirty. Changed since v4: - Rebase (no other changes). Changed since v5: - Typo fix. - Changed zap_page_range from MMU_MUNMAP to MMU_MIGRATE to reflect the fact that the address range is still valid just the page backing it are no longer. Changed since v6: - try_to_unmap_one() only invalidate when doing migration. - Differentiate fork from other case. Changed since v7: - Renamed MMU_HUGE_PAGE_SPLIT to MMU_HUGE_PAGE_SPLIT. - Renamed MMU_ISDIRTY to MMU_CLEAR_SOFT_DIRTY. - Renamed MMU_WRITE_PROTECT to MMU_KSM_WRITE_PROTECT. - English syntax fixes. Changed since v8: - Added freeze/unfreeze for new huge page splitting. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: Rik van Riel <riel@redhat.com>
-rw-r--r--drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c6
-rw-r--r--drivers/gpu/drm/i915/i915_gem_userptr.c3
-rw-r--r--drivers/gpu/drm/radeon/radeon_mn.c3
-rw-r--r--drivers/infiniband/core/umem_odp.c9
-rw-r--r--drivers/iommu/amd_iommu_v2.c3
-rw-r--r--drivers/iommu/intel-svm.c6
-rw-r--r--drivers/misc/sgi-gru/grutlbpurge.c9
-rw-r--r--drivers/xen/gntdev.c9
-rw-r--r--fs/proc/task_mmu.c6
-rw-r--r--include/linux/mmu_notifier.h137
-rw-r--r--kernel/events/uprobes.c10
-rw-r--r--mm/huge_memory.c27
-rw-r--r--mm/hugetlb.c23
-rw-r--r--mm/ksm.c18
-rw-r--r--mm/madvise.c4
-rw-r--r--mm/memory.c27
-rw-r--r--mm/migrate.c9
-rw-r--r--mm/mmu_notifier.c28
-rw-r--r--mm/mprotect.c6
-rw-r--r--mm/mremap.c6
-rw-r--r--mm/rmap.c4
-rw-r--r--virt/kvm/kvm_main.c12
22 files changed, 263 insertions, 102 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
index 9f4a45cd2aab..147015cc034a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -157,7 +157,8 @@ static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
*/
static void amdgpu_mn_invalidate_page(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long address)
+ unsigned long address,
+ enum mmu_event event)
{
struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
struct interval_tree_node *it;
@@ -189,7 +190,8 @@ static void amdgpu_mn_invalidate_page(struct mmu_notifier *mn,
static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
struct interval_tree_node *it;
diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c
index 18ba8139e922..3bfc683bb0e2 100644
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/i915_gem_userptr.c
@@ -112,7 +112,8 @@ static void del_object(struct i915_mmu_object *mo)
static void i915_gem_userptr_mn_invalidate_range_start(struct mmu_notifier *_mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct i915_mmu_notifier *mn =
container_of(_mn, struct i915_mmu_notifier, mn);
diff --git a/drivers/gpu/drm/radeon/radeon_mn.c b/drivers/gpu/drm/radeon/radeon_mn.c
index eef006c48584..3a9615b96a88 100644
--- a/drivers/gpu/drm/radeon/radeon_mn.c
+++ b/drivers/gpu/drm/radeon/radeon_mn.c
@@ -121,7 +121,8 @@ static void radeon_mn_release(struct mmu_notifier *mn,
static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
struct interval_tree_node *it;
diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c
index 75077a018675..aad511234d4b 100644
--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -165,7 +165,8 @@ 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)
+ unsigned long address,
+ enum mmu_event event)
{
struct ib_ucontext *context = container_of(mn, struct ib_ucontext, mn);
@@ -192,7 +193,8 @@ static int invalidate_range_start_trampoline(struct ib_umem *item, u64 start,
static void ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct ib_ucontext *context = container_of(mn, struct ib_ucontext, mn);
@@ -217,7 +219,8 @@ static int invalidate_range_end_trampoline(struct ib_umem *item, u64 start,
static void ib_umem_notifier_invalidate_range_end(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ 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 56999d2fac07..cba209e4d4e6 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -392,7 +392,8 @@ 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)
+ unsigned long address,
+ enum mmu_event event)
{
__mn_flush_page(mn, address);
}
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index d9939fa9b588..60decf3d14e3 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -209,7 +209,8 @@ static void intel_flush_svm_range(struct intel_svm *svm, unsigned long address,
}
static void intel_change_pte(struct mmu_notifier *mn, struct mm_struct *mm,
- unsigned long address, pte_t pte)
+ unsigned long address, pte_t pte,
+ enum mmu_event event)
{
struct intel_svm *svm = container_of(mn, struct intel_svm, notifier);
@@ -217,7 +218,8 @@ static void intel_change_pte(struct mmu_notifier *mn, struct mm_struct *mm,
}
static void intel_invalidate_page(struct mmu_notifier *mn, struct mm_struct *mm,
- unsigned long address)
+ unsigned long address,
+ enum mmu_event event)
{
struct intel_svm *svm = container_of(mn, struct intel_svm, notifier);
diff --git a/drivers/misc/sgi-gru/grutlbpurge.c b/drivers/misc/sgi-gru/grutlbpurge.c
index e936d43895d2..1c220ae60232 100644
--- a/drivers/misc/sgi-gru/grutlbpurge.c
+++ b/drivers/misc/sgi-gru/grutlbpurge.c
@@ -221,7 +221,8 @@ void gru_flush_all_tlb(struct gru_state *gru)
*/
static void gru_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start, unsigned long end,
+ enum mmu_event event)
{
struct gru_mm_struct *gms = container_of(mn, struct gru_mm_struct,
ms_notifier);
@@ -235,7 +236,8 @@ static void gru_invalidate_range_start(struct mmu_notifier *mn,
static void gru_invalidate_range_end(struct mmu_notifier *mn,
struct mm_struct *mm, unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct gru_mm_struct *gms = container_of(mn, struct gru_mm_struct,
ms_notifier);
@@ -248,7 +250,8 @@ 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)
+ unsigned long address,
+ enum mmu_event event)
{
struct gru_mm_struct *gms = container_of(mn, struct gru_mm_struct,
ms_notifier);
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index dc495383ad73..df7640c2f4af 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -467,7 +467,9 @@ static void unmap_if_in_range(struct grant_map *map,
static void mn_invl_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
struct grant_map *map;
@@ -484,9 +486,10 @@ 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)
+ unsigned long address,
+ enum mmu_event event)
{
- mn_invl_range_start(mn, mm, address, address + PAGE_SIZE);
+ mn_invl_range_start(mn, mm, address, address + PAGE_SIZE, event);
}
static void mn_release(struct mmu_notifier *mn,
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 229cb546bee0..3101b70dd273 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1051,11 +1051,13 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
downgrade_write(&mm->mmap_sem);
break;
}
- mmu_notifier_invalidate_range_start(mm, 0, -1);
+ mmu_notifier_invalidate_range_start(mm, 0, -1,
+ MMU_CLEAR_SOFT_DIRTY);
}
walk_page_range(0, ~0UL, &clear_refs_walk);
if (type == CLEAR_REFS_SOFT_DIRTY)
- mmu_notifier_invalidate_range_end(mm, 0, -1);
+ mmu_notifier_invalidate_range_end(mm, 0, -1,
+ MMU_CLEAR_SOFT_DIRTY);
flush_tlb_mm(mm);
up_read(&mm->mmap_sem);
out_mm:
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index a1a210d59961..906aad09022c 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -9,6 +9,72 @@
struct mmu_notifier;
struct mmu_notifier_ops;
+/* MMU Events report fine-grained information to the callback routine, allowing
+ * the event listener to make a more informed decision as to what action to
+ * take. The event types are:
+ *
+ * - MMU_FORK a process is forking. This will lead to vmas getting
+ * write-protected, in order to set up COW
+ *
+ * - MMU_HUGE_PAGE_SPLIT the pages don't move, nor does their content change,
+ * but the page table structure is updated (levels added or removed).
+ *
+ * - MMU_HUGE_FREEZE/MMU_HUGE_UNFREEZE huge page splitting is a multi-step,
+ * first pmd is freeze and then split before being unfreeze.
+ *
+ * - MMU_CLEAR_SOFT_DIRTY need to write protect so write properly update the
+ * soft dirty bit of page table entry.
+ *
+ * - MMU_MIGRATE: memory is migrating from one page to another, thus all write
+ * access must stop after invalidate_range_start callback returns.
+ * Furthermore, no read access should be allowed either, as a new page can
+ * be remapped with write access before the invalidate_range_end callback
+ * happens and thus any read access to old page might read stale data. There
+ * are several sources for this event, including:
+ *
+ * - A page moving to swap (various reasons, including page reclaim),
+ * - An mremap syscall,
+ * - migration for NUMA reasons,
+ * - balancing the memory pool,
+ * - write fault on COW page,
+ * - and more that are not listed here.
+ *
+ * - MMU_MPROT: memory access protection is changing. Refer to the vma to get
+ * the new access protection. All memory access are still valid until the
+ * invalidate_range_end callback.
+ *
+ * - MMU_MUNLOCK: unlock memory. Content of page table stays the same but
+ * page are unlocked.
+ *
+ * - MMU_MUNMAP: the range is being unmapped (outcome of a munmap syscall or
+ * process destruction). However, access is still allowed, up until the
+ * invalidate_range_free_pages callback. This also implies that secondary
+ * page table can be trimmed, because the address range is no longer valid.
+ *
+ * - MMU_WRITE_BACK: memory is being written back to disk, all write accesses
+ * must stop after invalidate_range_start callback returns. Read access are
+ * still allowed.
+ *
+ * - MMU_KSM_WRITE_PROTECT: memory is being write protected for KSM.
+ *
+ * If in doubt when adding a new notifier caller, please use MMU_MIGRATE,
+ * because it will always lead to reasonable behavior, but will not allow the
+ * listener a chance to optimize its events.
+ */
+enum mmu_event {
+ MMU_FORK = 0,
+ MMU_HUGE_PAGE_SPLIT,
+ MMU_HUGE_FREEZE,
+ MMU_HUGE_UNFREEZE,
+ MMU_CLEAR_SOFT_DIRTY,
+ MMU_MIGRATE,
+ MMU_MPROT,
+ MMU_MUNLOCK,
+ MMU_MUNMAP,
+ MMU_WRITE_BACK,
+ MMU_KSM_WRITE_PROTECT,
+};
+
#ifdef CONFIG_MMU_NOTIFIER
/*
@@ -92,7 +158,8 @@ struct mmu_notifier_ops {
void (*change_pte)(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long address,
- pte_t pte);
+ pte_t pte,
+ enum mmu_event event);
/*
* Before this is invoked any secondary MMU is still ok to
@@ -103,7 +170,8 @@ struct mmu_notifier_ops {
*/
void (*invalidate_page)(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long address);
+ unsigned long address,
+ enum mmu_event event);
/*
* invalidate_range_start() and invalidate_range_end() must be
@@ -150,10 +218,14 @@ struct mmu_notifier_ops {
*/
void (*invalidate_range_start)(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long start, unsigned long end);
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event);
void (*invalidate_range_end)(struct mmu_notifier *mn,
struct mm_struct *mm,
- unsigned long start, unsigned long end);
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event);
/*
* invalidate_range() is either called between
@@ -219,13 +291,20 @@ extern int __mmu_notifier_clear_young(struct mm_struct *mm,
extern int __mmu_notifier_test_young(struct mm_struct *mm,
unsigned long address);
extern void __mmu_notifier_change_pte(struct mm_struct *mm,
- unsigned long address, pte_t pte);
+ unsigned long address,
+ pte_t pte,
+ enum mmu_event event);
extern void __mmu_notifier_invalidate_page(struct mm_struct *mm,
- unsigned long address);
+ unsigned long address,
+ enum mmu_event event);
extern void __mmu_notifier_invalidate_range_start(struct mm_struct *mm,
- unsigned long start, unsigned long end);
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event);
extern void __mmu_notifier_invalidate_range_end(struct mm_struct *mm,
- unsigned long start, unsigned long end);
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event);
extern void __mmu_notifier_invalidate_range(struct mm_struct *mm,
unsigned long start, unsigned long end);
@@ -262,31 +341,38 @@ static inline int mmu_notifier_test_young(struct mm_struct *mm,
}
static inline void mmu_notifier_change_pte(struct mm_struct *mm,
- unsigned long address, pte_t pte)
+ unsigned long address,
+ pte_t pte,
+ enum mmu_event event)
{
if (mm_has_notifiers(mm))
- __mmu_notifier_change_pte(mm, address, pte);
+ __mmu_notifier_change_pte(mm, address, pte, event);
}
static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
- unsigned long address)
+ unsigned long address,
+ enum mmu_event event)
{
if (mm_has_notifiers(mm))
- __mmu_notifier_invalidate_page(mm, address);
+ __mmu_notifier_invalidate_page(mm, address, event);
}
static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
if (mm_has_notifiers(mm))
- __mmu_notifier_invalidate_range_start(mm, start, end);
+ __mmu_notifier_invalidate_range_start(mm, start, end, event);
}
static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
if (mm_has_notifiers(mm))
- __mmu_notifier_invalidate_range_end(mm, start, end);
+ __mmu_notifier_invalidate_range_end(mm, start, end, event);
}
static inline void mmu_notifier_invalidate_range(struct mm_struct *mm,
@@ -403,13 +489,13 @@ static inline void mmu_notifier_mm_destroy(struct mm_struct *mm)
* 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) \
+#define set_pte_at_notify(__mm, __address, __ptep, __pte, __event) \
({ \
struct mm_struct *___mm = __mm; \
unsigned long ___address = __address; \
pte_t ___pte = __pte; \
\
- mmu_notifier_change_pte(___mm, ___address, ___pte); \
+ mmu_notifier_change_pte(___mm, ___address, ___pte, __event); \
set_pte_at(___mm, ___address, __ptep, ___pte); \
})
@@ -437,22 +523,29 @@ static inline int mmu_notifier_test_young(struct mm_struct *mm,
}
static inline void mmu_notifier_change_pte(struct mm_struct *mm,
- unsigned long address, pte_t pte)
+ unsigned long address,
+ pte_t pte,
+ enum mmu_event event)
{
}
static inline void mmu_notifier_invalidate_page(struct mm_struct *mm,
- unsigned long address)
+ unsigned long address,
+ enum mmu_event event)
{
}
static inline void mmu_notifier_invalidate_range_start(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
}
static inline void mmu_notifier_invalidate_range_end(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
}
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 7edc95edfaee..fbe307205bcc 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -169,7 +169,8 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
/* For try_to_free_swap() and munlock_vma_page() below */
lock_page(page);
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
err = -EAGAIN;
ptep = page_check_address(page, mm, addr, &ptl, 0);
if (!ptep)
@@ -187,7 +188,9 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush_notify(vma, addr, ptep);
- set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot));
+ set_pte_at_notify(mm, addr, ptep,
+ mk_pte(kpage, vma->vm_page_prot),
+ MMU_MIGRATE);
page_remove_rmap(page, false);
if (!page_mapped(page))
@@ -201,7 +204,8 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
err = 0;
unlock:
mem_cgroup_cancel_charge(kpage, memcg, false);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
unlock_page(page);
return err;
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 86f9f8b82f8e..1eecc2dce473 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1218,7 +1218,8 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
mmun_start = haddr;
mmun_end = haddr + HPAGE_PMD_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, orig_pmd)))
@@ -1252,7 +1253,8 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
page_remove_rmap(page, true);
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
ret |= VM_FAULT_WRITE;
put_page(page);
@@ -1262,7 +1264,8 @@ out:
out_free_pages:
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
for (i = 0; i < HPAGE_PMD_NR; i++) {
memcg = (void *)page_private(pages[i]);
set_page_private(pages[i], 0);
@@ -1367,7 +1370,8 @@ alloc:
mmun_start = haddr;
mmun_end = haddr + HPAGE_PMD_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
spin_lock(ptl);
if (page)
@@ -1399,7 +1403,8 @@ alloc:
}
spin_unlock(ptl);
out_mn:
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
out:
return ret;
out_unlock:
@@ -2430,7 +2435,8 @@ static void collapse_huge_page(struct mm_struct *mm,
mmun_start = address;
mmun_end = address + HPAGE_PMD_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
pmd_ptl = pmd_lock(mm, pmd); /* probably unnecessary */
/*
* After this gup_fast can't run anymore. This also removes
@@ -2440,7 +2446,8 @@ static void collapse_huge_page(struct mm_struct *mm,
*/
_pmd = pmdp_collapse_flush(vma, address, pmd);
spin_unlock(pmd_ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
spin_lock(pte_ptl);
isolated = __collapse_huge_page_isolate(vma, address, pte);
@@ -2994,7 +3001,8 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
struct mm_struct *mm = vma->vm_mm;
unsigned long haddr = address & HPAGE_PMD_MASK;
- mmu_notifier_invalidate_range_start(mm, haddr, haddr + HPAGE_PMD_SIZE);
+ mmu_notifier_invalidate_range_start(mm, haddr, haddr + HPAGE_PMD_SIZE,
+ MMU_HUGE_PAGE_SPLIT);
ptl = pmd_lock(mm, pmd);
if (pmd_trans_huge(*pmd)) {
struct page *page = pmd_page(*pmd);
@@ -3005,7 +3013,8 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
__split_huge_pmd_locked(vma, pmd, haddr, freeze);
out:
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, haddr, haddr + HPAGE_PMD_SIZE);
+ mmu_notifier_invalidate_range_end(mm, haddr, haddr + HPAGE_PMD_SIZE,
+ MMU_HUGE_PAGE_SPLIT);
}
void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 19d0d08b396f..c22f2c1c7da0 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3058,7 +3058,8 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
mmun_start = vma->vm_start;
mmun_end = vma->vm_end;
if (cow)
- mmu_notifier_invalidate_range_start(src, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(src, mmun_start,
+ mmun_end, MMU_MIGRATE);
for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) {
spinlock_t *src_ptl, *dst_ptl;
@@ -3113,7 +3114,8 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
}
if (cow)
- mmu_notifier_invalidate_range_end(src, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(src, mmun_start,
+ mmun_end, MMU_MIGRATE);
return ret;
}
@@ -3139,7 +3141,8 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
BUG_ON(end & ~huge_page_mask(h));
tlb_start_vma(tlb, vma);
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
address = start;
again:
for (; address < end; address += sz) {
@@ -3214,7 +3217,8 @@ unlock:
if (address < end && !ref_page)
goto again;
}
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
tlb_end_vma(tlb, vma);
}
@@ -3401,8 +3405,8 @@ retry_avoidcopy:
mmun_start = address & huge_page_mask(h);
mmun_end = mmun_start + huge_page_size(h);
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
-
+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
/*
* Retake the page table lock to check for racing updates
* before the page tables are altered
@@ -3423,7 +3427,8 @@ retry_avoidcopy:
new_page = old_page;
}
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
out_release_all:
put_page(new_page);
out_release_old:
@@ -3906,7 +3911,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
BUG_ON(address >= end);
flush_cache_range(vma, address, end);
- mmu_notifier_invalidate_range_start(mm, start, end);
+ mmu_notifier_invalidate_range_start(mm, start, end, MMU_MPROT);
i_mmap_lock_write(vma->vm_file->f_mapping);
for (; address < end; address += huge_page_size(h)) {
spinlock_t *ptl;
@@ -3956,7 +3961,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
flush_tlb_range(vma, start, end);
mmu_notifier_invalidate_range(mm, start, end);
i_mmap_unlock_write(vma->vm_file->f_mapping);
- mmu_notifier_invalidate_range_end(mm, start, end);
+ mmu_notifier_invalidate_range_end(mm, start, end, MMU_MPROT);
return pages << h->order;
}
diff --git a/mm/ksm.c b/mm/ksm.c
index b99e828172f6..19ee11f6f9a6 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -863,7 +863,8 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
mmun_start = addr;
mmun_end = addr + PAGE_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end,
+ MMU_KSM_WRITE_PROTECT);
ptep = page_check_address(page, mm, addr, &ptl, 0);
if (!ptep)
@@ -895,7 +896,7 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
if (pte_dirty(entry))
set_page_dirty(page);
entry = pte_mkclean(pte_wrprotect(entry));
- set_pte_at_notify(mm, addr, ptep, entry);
+ set_pte_at_notify(mm, addr, ptep, entry, MMU_KSM_WRITE_PROTECT);
}
*orig_pte = *ptep;
err = 0;
@@ -903,7 +904,8 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
out_unlock:
pte_unmap_unlock(ptep, ptl);
out_mn:
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end,
+ MMU_KSM_WRITE_PROTECT);
out:
return err;
}
@@ -939,7 +941,8 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
mmun_start = addr;
mmun_end = addr + PAGE_SIZE;
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
ptep = pte_offset_map_lock(mm, pmd, addr, &ptl);
if (!pte_same(*ptep, orig_pte)) {
@@ -952,7 +955,9 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush_notify(vma, addr, ptep);
- set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot));
+ set_pte_at_notify(mm, addr, ptep,
+ mk_pte(kpage, vma->vm_page_prot),
+ MMU_MIGRATE);
page_remove_rmap(page, false);
if (!page_mapped(page))
@@ -962,7 +967,8 @@ static int replace_page(struct vm_area_struct *vma, struct page *page,
pte_unmap_unlock(ptep, ptl);
err = 0;
out_mn:
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end,
+ MMU_MIGRATE);
out:
return err;
}
diff --git a/mm/madvise.c b/mm/madvise.c
index 07427d3fcead..7b384db6b179 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -432,9 +432,9 @@ static int madvise_free_single_vma(struct vm_area_struct *vma,
tlb_gather_mmu(&tlb, mm, start, end);
update_hiwater_rss(mm);
- mmu_notifier_invalidate_range_start(mm, start, end);
+ mmu_notifier_invalidate_range_start(mm, start, end, MMU_MUNMAP);
madvise_free_page_range(&tlb, vma, start, end);
- mmu_notifier_invalidate_range_end(mm, start, end);
+ mmu_notifier_invalidate_range_end(mm, start, end, MMU_MUNMAP);
tlb_finish_mmu(&tlb, start, end);
return 0;
diff --git a/mm/memory.c b/mm/memory.c
index 93897f23cc11..28d771745b3d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1035,7 +1035,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
mmun_end = end;
if (is_cow)
mmu_notifier_invalidate_range_start(src_mm, mmun_start,
- mmun_end);
+ mmun_end, MMU_FORK);
ret = 0;
dst_pgd = pgd_offset(dst_mm, addr);
@@ -1052,7 +1052,8 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
} while (dst_pgd++, src_pgd++, addr = next, addr != end);
if (is_cow)
- mmu_notifier_invalidate_range_end(src_mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(src_mm, mmun_start,
+ mmun_end, MMU_FORK);
return ret;
}
@@ -1320,10 +1321,12 @@ void unmap_vmas(struct mmu_gather *tlb,
{
struct mm_struct *mm = vma->vm_mm;
- mmu_notifier_invalidate_range_start(mm, start_addr, end_addr);
+ mmu_notifier_invalidate_range_start(mm, start_addr,
+ end_addr, MMU_MUNMAP);
for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next)
unmap_single_vma(tlb, vma, start_addr, end_addr, NULL);
- mmu_notifier_invalidate_range_end(mm, start_addr, end_addr);
+ mmu_notifier_invalidate_range_end(mm, start_addr,
+ end_addr, MMU_MUNMAP);
}
/**
@@ -1345,10 +1348,10 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
lru_add_drain();
tlb_gather_mmu(&tlb, mm, start, end);
update_hiwater_rss(mm);
- mmu_notifier_invalidate_range_start(mm, start, end);
+ mmu_notifier_invalidate_range_start(mm, start, end, MMU_MIGRATE);
for ( ; vma && vma->vm_start < end; vma = vma->vm_next)
unmap_single_vma(&tlb, vma, start, end, details);
- mmu_notifier_invalidate_range_end(mm, start, end);
+ mmu_notifier_invalidate_range_end(mm, start, end, MMU_MIGRATE);
tlb_finish_mmu(&tlb, start, end);
}
@@ -1371,9 +1374,9 @@ static void zap_page_range_single(struct vm_area_struct *vma, unsigned long addr
lru_add_drain();
tlb_gather_mmu(&tlb, mm, address, end);
update_hiwater_rss(mm);
- mmu_notifier_invalidate_range_start(mm, address, end);
+ mmu_notifier_invalidate_range_start(mm, address, end, MMU_MUNMAP);
unmap_single_vma(&tlb, vma, address, end, details);
- mmu_notifier_invalidate_range_end(mm, address, end);
+ mmu_notifier_invalidate_range_end(mm, address, end, MMU_MUNMAP);
tlb_finish_mmu(&tlb, address, end);
}
@@ -2118,7 +2121,8 @@ static int wp_page_copy(struct mm_struct *mm, struct vm_area_struct *vma,
__SetPageUptodate(new_page);
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
/*
* Re-check the pte - we dropped the lock
@@ -2152,7 +2156,7 @@ static int wp_page_copy(struct mm_struct *mm, struct vm_area_struct *vma,
* 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);
+ set_pte_at_notify(mm, address, page_table, entry, MMU_MIGRATE);
update_mmu_cache(vma, address, page_table);
if (old_page) {
/*
@@ -2191,7 +2195,8 @@ static int wp_page_copy(struct mm_struct *mm, struct vm_area_struct *vma,
put_page(new_page);
pte_unmap_unlock(page_table, ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
if (old_page) {
/*
* Don't let another task, with possibly unlocked vma,
diff --git a/mm/migrate.c b/mm/migrate.c
index 6c822a7b27e0..f9d911e9d651 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1794,12 +1794,14 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
WARN_ON(PageLRU(new_page));
/* Recheck the target PMD */
- mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, entry) || page_count(page) != 2)) {
fail_putback:
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
/* Reverse changes made by migrate_page_copy() */
if (TestClearPageActive(new_page))
@@ -1851,7 +1853,8 @@ fail_putback:
set_page_owner_migrate_reason(new_page, MR_NUMA_MISPLACED);
spin_unlock(ptl);
- mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
/* Take an "isolate" reference and put new page on the LRU. */
get_page(new_page);
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index f4259e496f83..7e34526a29d2 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -159,8 +159,10 @@ int __mmu_notifier_test_young(struct mm_struct *mm,
return young;
}
-void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address,
- pte_t pte)
+void __mmu_notifier_change_pte(struct mm_struct *mm,
+ unsigned long address,
+ pte_t pte,
+ enum mmu_event event)
{
struct mmu_notifier *mn;
int id;
@@ -168,13 +170,14 @@ void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address,
id = srcu_read_lock(&srcu);
hlist_for_each_entry_rcu(mn, &mm->mmu_notifier_mm->list, hlist) {
if (mn->ops->change_pte)
- mn->ops->change_pte(mn, mm, address, pte);
+ mn->ops->change_pte(mn, mm, address, pte, event);
}
srcu_read_unlock(&srcu, id);
}
void __mmu_notifier_invalidate_page(struct mm_struct *mm,
- unsigned long address)
+ unsigned long address,
+ enum mmu_event event)
{
struct mmu_notifier *mn;
int id;
@@ -182,13 +185,16 @@ 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);
+ mn->ops->invalidate_page(mn, mm, address, event);
}
srcu_read_unlock(&srcu, id);
}
void __mmu_notifier_invalidate_range_start(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
+
{
struct mmu_notifier *mn;
int id;
@@ -196,14 +202,17 @@ void __mmu_notifier_invalidate_range_start(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_range_start)
- mn->ops->invalidate_range_start(mn, mm, start, end);
+ mn->ops->invalidate_range_start(mn, mm, start,
+ end, event);
}
srcu_read_unlock(&srcu, id);
}
EXPORT_SYMBOL_GPL(__mmu_notifier_invalidate_range_start);
void __mmu_notifier_invalidate_range_end(struct mm_struct *mm,
- unsigned long start, unsigned long end)
+ unsigned long start,
+ unsigned long end,
+ enum mmu_event event)
{
struct mmu_notifier *mn;
int id;
@@ -221,7 +230,8 @@ void __mmu_notifier_invalidate_range_end(struct mm_struct *mm,
if (mn->ops->invalidate_range)
mn->ops->invalidate_range(mn, mm, start, end);
if (mn->ops->invalidate_range_end)
- mn->ops->invalidate_range_end(mn, mm, start, end);
+ mn->ops->invalidate_range_end(mn, mm, start,
+ end, event);
}
srcu_read_unlock(&srcu, id);
}
diff --git a/mm/mprotect.c b/mm/mprotect.c
index b650c5412f58..64ee26fb451d 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -157,7 +157,8 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
/* invoke the mmu notifier if the pmd is populated */
if (!mni_start) {
mni_start = addr;
- mmu_notifier_invalidate_range_start(mm, mni_start, end);
+ mmu_notifier_invalidate_range_start(mm, mni_start,
+ end, MMU_MPROT);
}
if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) {
@@ -187,7 +188,8 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
} while (pmd++, addr = next, addr != end);
if (mni_start)
- mmu_notifier_invalidate_range_end(mm, mni_start, end);
+ mmu_notifier_invalidate_range_end(mm, mni_start, end,
+ MMU_MPROT);
if (nr_huge_updates)
count_vm_numa_events(NUMA_HUGE_PTE_UPDATES, nr_huge_updates);
diff --git a/mm/mremap.c b/mm/mremap.c
index 3fa0a467df66..9544022ca67a 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -175,7 +175,8 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
mmun_start = old_addr;
mmun_end = old_end;
- mmu_notifier_invalidate_range_start(vma->vm_mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_start(vma->vm_mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
for (; old_addr < old_end; old_addr += extent, new_addr += extent) {
cond_resched();
@@ -227,7 +228,8 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
if (likely(need_flush))
flush_tlb_range(vma, old_end-len, old_addr);
- mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start, mmun_end);
+ mmu_notifier_invalidate_range_end(vma->vm_mm, mmun_start,
+ mmun_end, MMU_MIGRATE);
return len + old_addr - old_end; /* how much done */
}
diff --git a/mm/rmap.c b/mm/rmap.c
index 307b555024ef..da96c7bb28a0 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1040,7 +1040,7 @@ 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_notifier_invalidate_page(mm, address, MMU_WRITE_BACK);
(*cleaned)++;
}
out:
@@ -1546,7 +1546,7 @@ 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_notifier_invalidate_page(mm, address, MMU_MIGRATE);
out:
return ret;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4fd482fb9260..62dd45e9b86f 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -275,7 +275,8 @@ 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)
+ unsigned long address,
+ enum mmu_event event)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int need_tlb_flush, idx;
@@ -317,7 +318,8 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long address,
- pte_t pte)
+ pte_t pte,
+ enum mmu_event event)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int idx;
@@ -333,7 +335,8 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int need_tlb_flush = 0, idx;
@@ -359,7 +362,8 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ enum mmu_event event)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);