diff mbox series

[v3,03/10] KVM: x86/mmu: Grab mmu_invalidate_seq in kvm_faultin_pfn()

Message ID 20220921173546.2674386-4-dmatlack@google.com (mailing list archive)
State New, archived
Headers show
Series KVM: x86/mmu: Make tdp_mmu read-only and clean up TPD MMU fault handler | expand

Commit Message

David Matlack Sept. 21, 2022, 5:35 p.m. UTC 
Grab mmu_invalidate_seq in kvm_faultin_pfn() and stash it in struct
kvm_page_fault. The eliminates duplicate code and reduces the amount of
parameters needed for is_page_fault_stale().

Preemptively split out __kvm_faultin_pfn() to a separate function for
use in subsequent commits.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/kvm/mmu/mmu.c          | 21 ++++++++++++---------
 arch/x86/kvm/mmu/mmu_internal.h |  1 +
 arch/x86/kvm/mmu/paging_tmpl.h  |  6 +-----
 3 files changed, 14 insertions(+), 14 deletions(-)

Comments

Isaku Yamahata Oct. 3, 2022, 7:05 p.m. UTC | #1 
On Wed, Sep 21, 2022 at 10:35:39AM -0700,
David Matlack <dmatlack@google.com> wrote:

> Grab mmu_invalidate_seq in kvm_faultin_pfn() and stash it in struct
> kvm_page_fault. The eliminates duplicate code and reduces the amount of
> parameters needed for is_page_fault_stale().
> 
> Preemptively split out __kvm_faultin_pfn() to a separate function for
> use in subsequent commits.
> 
> No functional change intended.
> 
> Signed-off-by: David Matlack <dmatlack@google.com>
> ---
>  arch/x86/kvm/mmu/mmu.c          | 21 ++++++++++++---------
>  arch/x86/kvm/mmu/mmu_internal.h |  1 +
>  arch/x86/kvm/mmu/paging_tmpl.h  |  6 +-----
>  3 files changed, 14 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index dd261cd2ad4e..31b835d20762 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -4129,7 +4129,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
>  	kvm_mmu_do_page_fault(vcpu, work->cr2_or_gpa, 0, true);
>  }
>  
> -static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
> +static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
>  {
>  	struct kvm_memory_slot *slot = fault->slot;
>  	bool async;
> @@ -4185,12 +4185,20 @@ static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
>  	return RET_PF_CONTINUE;
>  }
>  
> +static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
> +{
> +	fault->mmu_seq = vcpu->kvm->mmu_invalidate_seq;
> +	smp_rmb();
> +
> +	return __kvm_faultin_pfn(vcpu, fault);
> +}
> +
>  /*
>   * Returns true if the page fault is stale and needs to be retried, i.e. if the
>   * root was invalidated by a memslot update or a relevant mmu_notifier fired.
>   */
>  static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
> -				struct kvm_page_fault *fault, int mmu_seq)
> +				struct kvm_page_fault *fault)
>  {
>  	struct kvm_mmu_page *sp = to_shadow_page(vcpu->arch.mmu->root.hpa);
>  
> @@ -4210,14 +4218,12 @@ static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
>  		return true;
>  
>  	return fault->slot &&
> -	       mmu_invalidate_retry_hva(vcpu->kvm, mmu_seq, fault->hva);
> +	       mmu_invalidate_retry_hva(vcpu->kvm, fault->mmu_seq, fault->hva);
>  }
>  
>  static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
>  {
>  	bool is_tdp_mmu_fault = is_tdp_mmu(vcpu->arch.mmu);
> -
> -	unsigned long mmu_seq;
>  	int r;
>  
>  	fault->gfn = fault->addr >> PAGE_SHIFT;
> @@ -4234,9 +4240,6 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
>  	if (r)
>  		return r;
>  
> -	mmu_seq = vcpu->kvm->mmu_invalidate_seq;
> -	smp_rmb();
> -
>  	r = kvm_faultin_pfn(vcpu, fault);
>  	if (r != RET_PF_CONTINUE)
>  		return r;
> @@ -4252,7 +4255,7 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
>  	else
>  		write_lock(&vcpu->kvm->mmu_lock);
>  
> -	if (is_page_fault_stale(vcpu, fault, mmu_seq))
> +	if (is_page_fault_stale(vcpu, fault))
>  		goto out_unlock;
>  
>  	r = make_mmu_pages_available(vcpu);
> diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
> index 582def531d4d..1c0a1e7c796d 100644
> --- a/arch/x86/kvm/mmu/mmu_internal.h
> +++ b/arch/x86/kvm/mmu/mmu_internal.h
> @@ -221,6 +221,7 @@ struct kvm_page_fault {
>  	struct kvm_memory_slot *slot;
>  
>  	/* Outputs of kvm_faultin_pfn.  */
> +	unsigned long mmu_seq;
>  	kvm_pfn_t pfn;
>  	hva_t hva;
>  	bool map_writable;
> diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
> index 39e0205e7300..98f4abce4eaf 100644
> --- a/arch/x86/kvm/mmu/paging_tmpl.h
> +++ b/arch/x86/kvm/mmu/paging_tmpl.h
> @@ -791,7 +791,6 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
>  {
>  	struct guest_walker walker;
>  	int r;
> -	unsigned long mmu_seq;
>  	bool is_self_change_mapping;
>  
>  	pgprintk("%s: addr %lx err %x\n", __func__, fault->addr, fault->error_code);
> @@ -838,9 +837,6 @@ 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_invalidate_seq;
> -	smp_rmb();
> -
>  	r = kvm_faultin_pfn(vcpu, fault);
>  	if (r != RET_PF_CONTINUE)
>  		return r;
> @@ -871,7 +867,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
>  	r = RET_PF_RETRY;
>  	write_lock(&vcpu->kvm->mmu_lock);
>  
> -	if (is_page_fault_stale(vcpu, fault, mmu_seq))
> +	if (is_page_fault_stale(vcpu, fault))
>  		goto out_unlock;
>  
>  	r = make_mmu_pages_available(vcpu);
> -- 
> 2.37.3.998.g577e59143f-goog
> 

Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
diff mbox series

Patch

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index dd261cd2ad4e..31b835d20762 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4129,7 +4129,7 @@  void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
 	kvm_mmu_do_page_fault(vcpu, work->cr2_or_gpa, 0, true);
 }
 
-static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
+static int __kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 {
 	struct kvm_memory_slot *slot = fault->slot;
 	bool async;
@@ -4185,12 +4185,20 @@  static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 	return RET_PF_CONTINUE;
 }
 
+static int kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
+{
+	fault->mmu_seq = vcpu->kvm->mmu_invalidate_seq;
+	smp_rmb();
+
+	return __kvm_faultin_pfn(vcpu, fault);
+}
+
 /*
  * Returns true if the page fault is stale and needs to be retried, i.e. if the
  * root was invalidated by a memslot update or a relevant mmu_notifier fired.
  */
 static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
-				struct kvm_page_fault *fault, int mmu_seq)
+				struct kvm_page_fault *fault)
 {
 	struct kvm_mmu_page *sp = to_shadow_page(vcpu->arch.mmu->root.hpa);
 
@@ -4210,14 +4218,12 @@  static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
 		return true;
 
 	return fault->slot &&
-	       mmu_invalidate_retry_hva(vcpu->kvm, mmu_seq, fault->hva);
+	       mmu_invalidate_retry_hva(vcpu->kvm, fault->mmu_seq, fault->hva);
 }
 
 static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 {
 	bool is_tdp_mmu_fault = is_tdp_mmu(vcpu->arch.mmu);
-
-	unsigned long mmu_seq;
 	int r;
 
 	fault->gfn = fault->addr >> PAGE_SHIFT;
@@ -4234,9 +4240,6 @@  static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
 	if (r)
 		return r;
 
-	mmu_seq = vcpu->kvm->mmu_invalidate_seq;
-	smp_rmb();
-
 	r = kvm_faultin_pfn(vcpu, fault);
 	if (r != RET_PF_CONTINUE)
 		return r;
@@ -4252,7 +4255,7 @@  static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
 	else
 		write_lock(&vcpu->kvm->mmu_lock);
 
-	if (is_page_fault_stale(vcpu, fault, mmu_seq))
+	if (is_page_fault_stale(vcpu, fault))
 		goto out_unlock;
 
 	r = make_mmu_pages_available(vcpu);
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 582def531d4d..1c0a1e7c796d 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -221,6 +221,7 @@  struct kvm_page_fault {
 	struct kvm_memory_slot *slot;
 
 	/* Outputs of kvm_faultin_pfn.  */
+	unsigned long mmu_seq;
 	kvm_pfn_t pfn;
 	hva_t hva;
 	bool map_writable;
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 39e0205e7300..98f4abce4eaf 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -791,7 +791,6 @@  static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
 {
 	struct guest_walker walker;
 	int r;
-	unsigned long mmu_seq;
 	bool is_self_change_mapping;
 
 	pgprintk("%s: addr %lx err %x\n", __func__, fault->addr, fault->error_code);
@@ -838,9 +837,6 @@  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_invalidate_seq;
-	smp_rmb();
-
 	r = kvm_faultin_pfn(vcpu, fault);
 	if (r != RET_PF_CONTINUE)
 		return r;
@@ -871,7 +867,7 @@  static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
 	r = RET_PF_RETRY;
 	write_lock(&vcpu->kvm->mmu_lock);
 
-	if (is_page_fault_stale(vcpu, fault, mmu_seq))
+	if (is_page_fault_stale(vcpu, fault))
 		goto out_unlock;
 
 	r = make_mmu_pages_available(vcpu);