[PATCH v7 08/14] KVM: Rename mmu_notifier_*

Chao Peng
2022-07-06T08:26:03Z

The sync mechanism between mmu_notifier and page fault handler employs
fields mmu_notifier_seq/count and mmu_notifier_range_start/end. For the
to be added private memory, there is the same mechanism needed but not
rely on mmu_notifier (It uses new introduced memfile_notifier). This
patch renames the existing fields and related helper functions to a
neutral name mmu_updating_* so private memory can reuse.

No functional change intended.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
---
arch/arm64/kvm/mmu.c | 8 ++---
arch/mips/kvm/mmu.c | 10 +++---
arch/powerpc/include/asm/kvm_book3s_64.h | 2 +-
arch/powerpc/kvm/book3s_64_mmu_host.c | 4 +--
arch/powerpc/kvm/book3s_64_mmu_hv.c | 4 +--
arch/powerpc/kvm/book3s_64_mmu_radix.c | 6 ++--
arch/powerpc/kvm/book3s_hv_nested.c | 2 +-
arch/powerpc/kvm/book3s_hv_rm_mmu.c | 8 ++---
arch/powerpc/kvm/e500_mmu_host.c | 4 +--
arch/riscv/kvm/mmu.c | 4 +--
arch/x86/kvm/mmu/mmu.c | 14 ++++----
arch/x86/kvm/mmu/paging_tmpl.h | 4 +--
include/linux/kvm_host.h | 38 ++++++++++-----------
virt/kvm/kvm_main.c | 42 +++++++++++-------------
virt/kvm/pfncache.c | 14 ++++----
15 files changed, 81 insertions(+), 83 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 87f1cd0df36e..7ee6fafc24ee 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -993,7 +993,7 @@ transparent_hugepage_adjust(struct kvm *kvm, struct kvm_memory_slot *memslot,
* THP doesn't start to split while we are adjusting the
* refcounts.
*
- * We are sure this doesn't happen, because mmu_notifier_retry
+ * We are sure this doesn't happen, because mmu_updating_retry
* was successful and we are holding the mmu_lock, so if this
* THP is trying to split, it will be blocked in the mmu
* notifier before touching any of the pages, specifically
@@ -1188,9 +1188,9 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
return ret;
}

- mmu_seq = vcpu->kvm->mmu_notifier_seq;
+ mmu_seq = vcpu->kvm->mmu_updating_seq;
/*
- * Ensure the read of mmu_notifier_seq happens before we call
+ * Ensure the read of mmu_updating_seq happens before we call
* gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk
* the page we just got a reference to gets unmapped before we have a
* chance to grab the mmu_lock, which ensure that if the page gets
@@ -1246,7 +1246,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
else
write_lock(&kvm->mmu_lock);
pgt = vcpu->arch.hw_mmu->pgt;
- if (mmu_notifier_retry(kvm, mmu_seq))
+ if (mmu_updating_retry(kvm, mmu_seq))
goto out_unlock;

/*
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 1bfd1b501d82..abd468c6a749 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -615,17 +615,17 @@ static int kvm_mips_map_page(struct kvm_vcpu *vcpu, unsigned long gpa,
* Used to check for invalidations in progress, of the pfn that is
* returned by pfn_to_pfn_prot below.
*/
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
/*
- * Ensure the read of mmu_notifier_seq isn't reordered with PTE reads in
+ * Ensure the read of mmu_updating_seq isn't reordered with PTE reads in
* gfn_to_pfn_prot() (which calls get_user_pages()), so that we don't
* risk the page we get a reference to getting unmapped before we have a
- * chance to grab the mmu_lock without mmu_notifier_retry() noticing.
+ * chance to grab the mmu_lock without mmu_updating_retry () noticing.
*
* This smp_rmb() pairs with the effective smp_wmb() of the combination
* of the pte_unmap_unlock() after the PTE is zapped, and the
* spin_lock() in kvm_mmu_notifier_invalidate_<page|range_end>() before
- * mmu_notifier_seq is incremented.
+ * mmu_updating_seq is incremented.
*/
smp_rmb();

@@ -638,7 +638,7 @@ static int kvm_mips_map_page(struct kvm_vcpu *vcpu, unsigned long gpa,

spin_lock(&kvm->mmu_lock);
/* Check if an invalidation has taken place since we got pfn */
- if (mmu_notifier_retry(kvm, mmu_seq)) {
+ if (mmu_updating_retry(kvm, mmu_seq)) {
/*
* This can happen when mappings are changed asynchronously, but
* also synchronously if a COW is triggered by
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 4def2bd17b9b..4d35fb913de5 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -666,7 +666,7 @@ static inline pte_t *find_kvm_host_pte(struct kvm *kvm, unsigned long mmu_seq,
VM_WARN(!spin_is_locked(&kvm->mmu_lock),
"%s called with kvm mmu_lock not held \n", __func__);

- if (mmu_notifier_retry(kvm, mmu_seq))
+ if (mmu_updating_retry(kvm, mmu_seq))
return NULL;

pte = __find_linux_pte(kvm->mm->pgd, ea, NULL, hshift);
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
index 1ae09992c9ea..78f1aae8cb60 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -90,7 +90,7 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
unsigned long pfn;

/* used to check for invalidations in progress */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

/* Get host physical address for gpa */
@@ -151,7 +151,7 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
cpte = kvmppc_mmu_hpte_cache_next(vcpu);

spin_lock(&kvm->mmu_lock);
- if (!cpte || mmu_notifier_retry(kvm, mmu_seq)) {
+ if (!cpte || mmu_updating_retry(kvm, mmu_seq)) {
r = -EAGAIN;
goto out_unlock;
}
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 514fd45c1994..bcdec6a6f2a7 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -578,7 +578,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_vcpu *vcpu,
return -EFAULT;

/* used to check for invalidations in progress */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

ret = -EFAULT;
@@ -693,7 +693,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_vcpu *vcpu,

/* Check if we might have been invalidated; let the guest retry if so */
ret = RESUME_GUEST;
- if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) {
+ if (mmu_updating_retry(vcpu->kvm, mmu_seq)) {
unlock_rmap(rmap);
goto out_unlock;
}
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 42851c32ff3b..c8890ccc3f40 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -639,7 +639,7 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
/* Check if we might have been invalidated; let the guest retry if so */
spin_lock(&kvm->mmu_lock);
ret = -EAGAIN;
- if (mmu_notifier_retry(kvm, mmu_seq))
+ if (mmu_updating_retry(kvm, mmu_seq))
goto out_unlock;

/* Now traverse again under the lock and change the tree */
@@ -829,7 +829,7 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
bool large_enable;

/* used to check for invalidations in progress */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

/*
@@ -1190,7 +1190,7 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm,
* Increase the mmu notifier sequence number to prevent any page
* fault that read the memslot earlier from writing a PTE.
*/
- kvm->mmu_notifier_seq++;
+ kvm->mmu_updating_seq++;
spin_unlock(&kvm->mmu_lock);
}

diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
index 0644732d1a25..09f841f730da 100644
--- a/arch/powerpc/kvm/book3s_hv_nested.c
+++ b/arch/powerpc/kvm/book3s_hv_nested.c
@@ -1579,7 +1579,7 @@ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
/* 2. Find the host pte for this L1 guest real address */

/* Used to check for invalidations in progress */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

/* See if can find translation in our partition scoped tables for L1 */
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 2257fb18cb72..952b504dc98a 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -219,7 +219,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
g_ptel = ptel;

/* used later to detect if we might have been invalidated */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

/* Find the memslot (if any) for this address */
@@ -366,7 +366,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
rmap = real_vmalloc_addr(rmap);
lock_rmap(rmap);
/* Check for pending invalidations under the rmap chain lock */
- if (mmu_notifier_retry(kvm, mmu_seq)) {
+ if (mmu_updating_retry(kvm, mmu_seq)) {
/* inval in progress, write a non-present HPTE */
pteh |= HPTE_V_ABSENT;
pteh &= ~HPTE_V_VALID;
@@ -932,7 +932,7 @@ static long kvmppc_do_h_page_init_zero(struct kvm_vcpu *vcpu,
int i;

/* Used later to detect if we might have been invalidated */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock);
@@ -960,7 +960,7 @@ static long kvmppc_do_h_page_init_copy(struct kvm_vcpu *vcpu,
long ret = H_SUCCESS;

/* Used later to detect if we might have been invalidated */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock);
diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index 7f16afc331ef..d7636b926f25 100644
--- a/arch/powerpc/kvm/e500_mmu_host.c
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -339,7 +339,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
unsigned long flags;

/* used to check for invalidations in progress */
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

/*
@@ -460,7 +460,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
}

spin_lock(&kvm->mmu_lock);
- if (mmu_notifier_retry(kvm, mmu_seq)) {
+ if (mmu_updating_retry(kvm, mmu_seq)) {
ret = -EAGAIN;
goto out;
}
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index 081f8d2b9cf3..a7db374d3861 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -654,7 +654,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
return ret;
}

- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;

hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writeable);
if (hfn == KVM_PFN_ERR_HWPOISON) {
@@ -674,7 +674,7 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,

spin_lock(&kvm->mmu_lock);

- if (mmu_notifier_retry(kvm, mmu_seq))
+ if (mmu_updating_retry(kvm, mmu_seq))
goto out_unlock;

if (writeable) {
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0d882fad4bc1..545eb74305fe 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2908,7 +2908,7 @@ static void direct_pte_prefetch(struct kvm_vcpu *vcpu, u64 *sptep)
* If addresses are being invalidated, skip prefetching to avoid
* accidentally prefetching those addresses.
*/
- if (unlikely(vcpu->kvm->mmu_notifier_count))
+ if (unlikely(vcpu->kvm->mmu_updating_count))
return;

__direct_pte_prefetch(vcpu, sp, sptep);
@@ -2950,7 +2950,7 @@ static int host_pfn_mapping_level(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn,
/*
* Lookup the mapping level in the current mm. The information
* may become stale soon, but it is safe to use as long as
- * 1) mmu_notifier_retry was checked after taking mmu_lock, and
+ * 1) mmu_updating_retry was checked after taking mmu_lock, and
* 2) mmu_lock is taken now.
*
* We still need to disable IRQs to prevent concurrent tear down
@@ -3035,7 +3035,7 @@ void kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
return;

/*
- * mmu_notifier_retry() was successful and mmu_lock is held, so
+ * mmu_updating_retry was successful and mmu_lock is held, so
* the pmd can't be split from under us.
*/
fault->goal_level = fault->req_level;
@@ -4182,7 +4182,7 @@ static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
return true;

return fault->slot &&
- mmu_notifier_retry_gfn(vcpu->kvm, mmu_seq, fault->gfn);
+ mmu_updating_retry_gfn(vcpu->kvm, mmu_seq, fault->gfn);
}

static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
@@ -4206,7 +4206,7 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
if (r)
return r;

- mmu_seq = vcpu->kvm->mmu_notifier_seq;
+ mmu_seq = vcpu->kvm->mmu_updating_seq;
smp_rmb();

r = kvm_faultin_pfn(vcpu, fault);
@@ -6023,7 +6023,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)

write_lock(&kvm->mmu_lock);

- kvm_inc_notifier_count(kvm, gfn_start, gfn_end);
+ kvm_mmu_updating_begin(kvm, gfn_start, gfn_end);

flush = __kvm_zap_rmaps(kvm, gfn_start, gfn_end);

@@ -6037,7 +6037,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
kvm_flush_remote_tlbs_with_address(kvm, gfn_start,
gfn_end - gfn_start);

- kvm_dec_notifier_count(kvm, gfn_start, gfn_end);
+ kvm_mmu_updating_end(kvm, gfn_start, gfn_end);

write_unlock(&kvm->mmu_lock);
}
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 2448fa8d8438..acf7e41aa02b 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -589,7 +589,7 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
* If addresses are being invalidated, skip prefetching to avoid
* accidentally prefetching those addresses.
*/
- if (unlikely(vcpu->kvm->mmu_notifier_count))
+ if (unlikely(vcpu->kvm->mmu_updating_count))
return;

if (sp->role.direct)
@@ -838,7 +838,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
else
fault->max_level = walker.level;

- mmu_seq = vcpu->kvm->mmu_notifier_seq;
+ mmu_seq = vcpu->kvm->mmu_updating_seq;
smp_rmb();

r = kvm_faultin_pfn(vcpu, fault);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index e9153b54e2a4..c262ebb168a7 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -765,10 +765,10 @@ struct kvm {

#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
struct mmu_notifier mmu_notifier;
- unsigned long mmu_notifier_seq;
- long mmu_notifier_count;
- gfn_t mmu_notifier_range_start;
- gfn_t mmu_notifier_range_end;
+ unsigned long mmu_updating_seq;
+ long mmu_updating_count;
+ gfn_t mmu_updating_range_start;
+ gfn_t mmu_updating_range_end;
#endif
struct list_head devices;
u64 manual_dirty_log_protect;
@@ -1362,8 +1362,8 @@ void kvm_mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc);
void *kvm_mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc);
#endif

-void kvm_inc_notifier_count(struct kvm *kvm, gfn_t start, gfn_t end);
-void kvm_dec_notifier_count(struct kvm *kvm, gfn_t start, gfn_t end);
+void kvm_mmu_updating_begin(struct kvm *kvm, gfn_t start, gfn_t end);
+void kvm_mmu_updating_end(struct kvm *kvm, gfn_t start, gfn_t end);

long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg);
@@ -1901,42 +1901,42 @@ extern const struct kvm_stats_header kvm_vcpu_stats_header;
extern const struct _kvm_stats_desc kvm_vcpu_stats_desc[];

#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
-static inline int mmu_notifier_retry(struct kvm *kvm, unsigned long mmu_seq)
+static inline int mmu_updating_retry(struct kvm *kvm, unsigned long mmu_seq)
{
- if (unlikely(kvm->mmu_notifier_count))
+ if (unlikely(kvm->mmu_updating_count))
return 1;
/*
- * Ensure the read of mmu_notifier_count happens before the read
- * of mmu_notifier_seq. This interacts with the smp_wmb() in
+ * Ensure the read of mmu_updating_count happens before the read
+ * of mmu_updating_seq. This interacts with the smp_wmb() in
* mmu_notifier_invalidate_range_end to make sure that the caller
- * either sees the old (non-zero) value of mmu_notifier_count or
- * the new (incremented) value of mmu_notifier_seq.
+ * either sees the old (non-zero) value of mmu_updating_count or
+ * the new (incremented) value of mmu_updating_seq.
* PowerPC Book3s HV KVM calls this under a per-page lock
* rather than under kvm->mmu_lock, for scalability, so
* can't rely on kvm->mmu_lock to keep things ordered.
*/
smp_rmb();
- if (kvm->mmu_notifier_seq != mmu_seq)
+ if (kvm->mmu_updating_seq != mmu_seq)
return 1;
return 0;
}

-static inline int mmu_notifier_retry_gfn(struct kvm *kvm,
+static inline int mmu_updating_retry_gfn(struct kvm *kvm,
unsigned long mmu_seq,
gfn_t gfn)
{
lockdep_assert_held(&kvm->mmu_lock);
/*
- * If mmu_notifier_count is non-zero, then the range maintained by
+ * If mmu_updating_count is non-zero, then the range maintained by
* kvm_mmu_notifier_invalidate_range_start contains all addresses that
* might be being invalidated. Note that it may include some false
* positives, due to shortcuts when handing concurrent invalidations.
*/
- if (unlikely(kvm->mmu_notifier_count) &&
- gfn >= kvm->mmu_notifier_range_start &&
- gfn < kvm->mmu_notifier_range_end)
+ if (unlikely(kvm->mmu_updating_count) &&
+ gfn >= kvm->mmu_updating_range_start &&
+ gfn < kvm->mmu_updating_range_end)
return 1;
- if (kvm->mmu_notifier_seq != mmu_seq)
+ if (kvm->mmu_updating_seq != mmu_seq)
return 1;
return 0;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4d7f0e72366f..3ae4944b9f15 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -698,30 +698,29 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,

/*
* .change_pte() must be surrounded by .invalidate_range_{start,end}().
- * If mmu_notifier_count is zero, then no in-progress invalidations,
+ * If mmu_updating_count is zero, then no in-progress invalidations,
* including this one, found a relevant memslot at start(); rechecking
* memslots here is unnecessary. Note, a false positive (count elevated
* by a different invalidation) is sub-optimal but functionally ok.
*/
WARN_ON_ONCE(!READ_ONCE(kvm->mn_active_invalidate_count));
- if (!READ_ONCE(kvm->mmu_notifier_count))
+ if (!READ_ONCE(kvm->mmu_updating_count))
return;

kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn);
}

-void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start,
- unsigned long end)
+void kvm_mmu_updating_begin(struct kvm *kvm, gfn_t start, gfn_t end)
{
/*
* The count increase must become visible at unlock time as no
* spte can be established without taking the mmu_lock and
* count is also read inside the mmu_lock critical section.
*/
- kvm->mmu_notifier_count++;
- if (likely(kvm->mmu_notifier_count == 1)) {
- kvm->mmu_notifier_range_start = start;
- kvm->mmu_notifier_range_end = end;
+ kvm->mmu_updating_count++;
+ if (likely(kvm->mmu_updating_count == 1)) {
+ kvm->mmu_updating_range_start = start;
+ kvm->mmu_updating_range_end = end;
} else {
/*
* Fully tracking multiple concurrent ranges has diminishing
@@ -732,10 +731,10 @@ void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start,
* accumulate and persist until all outstanding invalidates
* complete.
*/
- kvm->mmu_notifier_range_start =
- min(kvm->mmu_notifier_range_start, start);
- kvm->mmu_notifier_range_end =
- max(kvm->mmu_notifier_range_end, end);
+ kvm->mmu_updating_range_start =
+ min(kvm->mmu_updating_range_start, start);
+ kvm->mmu_updating_range_end =
+ max(kvm->mmu_updating_range_end, end);
}
}

@@ -748,7 +747,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
.end = range->end,
.pte = __pte(0),
.handler = kvm_unmap_gfn_range,
- .on_lock = kvm_inc_notifier_count,
+ .on_lock = kvm_mmu_updating_begin,
.on_unlock = kvm_arch_guest_memory_reclaimed,
.flush_on_ret = true,
.may_block = mmu_notifier_range_blockable(range),
@@ -759,7 +758,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
/*
* Prevent memslot modification between range_start() and range_end()
* so that conditionally locking provides the same result in both
- * functions. Without that guarantee, the mmu_notifier_count
+ * functions. Without that guarantee, the mmu_updating_count
* adjustments will be imbalanced.
*
* Pairs with the decrement in range_end().
@@ -775,7 +774,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
* any given time, and the caches themselves can check for hva overlap,
* i.e. don't need to rely on memslot overlap checks for performance.
* Because this runs without holding mmu_lock, the pfn caches must use
- * mn_active_invalidate_count (see above) instead of mmu_notifier_count.
+ * mn_active_invalidate_count (see above) instead of mmu_updating_count.
*/
gfn_to_pfn_cache_invalidate_start(kvm, range->start, range->end,
hva_range.may_block);
@@ -785,22 +784,21 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
return 0;
}

-void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start,
- unsigned long end)
+void kvm_mmu_updating_end(struct kvm *kvm, gfn_t start, gfn_t end)
{
/*
* This sequence increase will notify the kvm page fault that
* the page that is going to be mapped in the spte could have
* been freed.
*/
- kvm->mmu_notifier_seq++;
+ kvm->mmu_updating_seq++;
smp_wmb();
/*
* The above sequence increase must be visible before the
* below count decrease, which is ensured by the smp_wmb above
- * in conjunction with the smp_rmb in mmu_notifier_retry().
+ * in conjunction with the smp_rmb in mmu_updating_retry().
*/
- kvm->mmu_notifier_count--;
+ kvm->mmu_updating_count--;
}

static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
@@ -812,7 +810,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
.end = range->end,
.pte = __pte(0),
.handler = (void *)kvm_null_fn,
- .on_lock = kvm_dec_notifier_count,
+ .on_lock = kvm_mmu_updating_end,
.on_unlock = (void *)kvm_null_fn,
.flush_on_ret = false,
.may_block = mmu_notifier_range_blockable(range),
@@ -833,7 +831,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
if (wake)
rcuwait_wake_up(&kvm->mn_memslots_update_rcuwait);

- BUG_ON(kvm->mmu_notifier_count < 0);
+ BUG_ON(kvm->mmu_updating_count < 0);
}

static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
index ab519f72f2cd..aa6d24966a76 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -112,27 +112,27 @@ static inline bool mmu_notifier_retry_cache(struct kvm *kvm, unsigned long mmu_s
{
/*
* mn_active_invalidate_count acts for all intents and purposes
- * like mmu_notifier_count here; but the latter cannot be used
+ * like mmu_updating_count here; but the latter cannot be used
* here because the invalidation of caches in the mmu_notifier
- * event occurs _before_ mmu_notifier_count is elevated.
+ * event occurs _before_ mmu_updating_count is elevated.
*
* Note, it does not matter that mn_active_invalidate_count
* is not protected by gpc->lock. It is guaranteed to
* be elevated before the mmu_notifier acquires gpc->lock, and
- * isn't dropped until after mmu_notifier_seq is updated.
+ * isn't dropped until after mmu_updating_seq is updated.
*/
if (kvm->mn_active_invalidate_count)
return true;

/*
* Ensure mn_active_invalidate_count is read before
- * mmu_notifier_seq. This pairs with the smp_wmb() in
+ * mmu_updating_seq. This pairs with the smp_wmb() in
* mmu_notifier_invalidate_range_end() to guarantee either the
* old (non-zero) value of mn_active_invalidate_count or the
- * new (incremented) value of mmu_notifier_seq is observed.
+ * new (incremented) value of mmu_updating_seq is observed.
*/
smp_rmb();
- return kvm->mmu_notifier_seq != mmu_seq;
+ return kvm->mmu_updating_seq != mmu_seq;
}

static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc)
@@ -155,7 +155,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc)
gpc->valid = false;

do {
- mmu_seq = kvm->mmu_notifier_seq;
+ mmu_seq = kvm->mmu_updating_seq;
smp_rmb();

write_unlock_irq(&gpc->lock);
--
2.25.1