Commit ba6e3fe2 authored by David Matlack's avatar David Matlack Committed by Paolo Bonzini
Browse files

KVM: x86/mmu: Grab mmu_invalidate_seq in kvm_faultin_pfn() 



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: default avatarDavid Matlack <dmatlack@google.com>
Reviewed-by: default avatarIsaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220921173546.2674386-4-dmatlack@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 09732d2b

arch/x86/kvm/mmu/mmu.c

+12 −9
Original line number Diff line number Diff line
@@ -4189,7 +4189,7 @@ 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;
@@ -4250,12 +4250,20 @@ 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);
@@ -4275,14 +4283,12 @@ 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;
@@ -4299,9 +4305,6 @@ 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;
@@ -4317,7 +4320,7 @@ 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);

arch/x86/kvm/mmu/mmu_internal.h

+1 −0
Original line number Diff line number Diff line
@@ -222,6 +222,7 @@ 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;

arch/x86/kvm/mmu/paging_tmpl.h

+1 −5
Original line number Diff line number Diff line
@@ -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);