Commit 09072daf authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: Unify kvm_mmu_pre_write() and kvm_mmu_post_write() 



Instead of calling two functions and repeating expensive checks, call one
function and provide it with before/after information.

Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 62135845

drivers/kvm/kvm.h

+2 −2
Original line number Diff line number Diff line
@@ -525,8 +525,8 @@ int kvm_write_guest(struct kvm_vcpu *vcpu, 


unsigned long segment_base(u16 selector);



void kvm_mmu_pre_write(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes);

void kvm_mmu_post_write(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes);

void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,

		       const u8 *old, const u8 *new, int bytes);

int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva);

void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu);

drivers/kvm/kvm_main.c

+2 −2
Original line number Diff line number Diff line
@@ -1071,18 +1071,18 @@ static int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, 
{

	struct page *page;

	void *virt;

	unsigned offset = offset_in_page(gpa);



	if (((gpa + bytes - 1) >> PAGE_SHIFT) != (gpa >> PAGE_SHIFT))

		return 0;

	page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);

	if (!page)

		return 0;

	kvm_mmu_pre_write(vcpu, gpa, bytes);

	mark_page_dirty(vcpu->kvm, gpa >> PAGE_SHIFT);

	virt = kmap_atomic(page, KM_USER0);

	kvm_mmu_pte_write(vcpu, gpa, virt + offset, val, bytes);

	memcpy(virt + offset_in_page(gpa), val, bytes);

	kunmap_atomic(virt, KM_USER0);

	kvm_mmu_post_write(vcpu, gpa, bytes);

	return 1;

}

drivers/kvm/mmu.c

+4 −7
Original line number Diff line number Diff line
@@ -1118,7 +1118,7 @@ int kvm_mmu_reset_context(struct kvm_vcpu *vcpu) 
	return r;

}



static void mmu_pre_write_zap_pte(struct kvm_vcpu *vcpu,

static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,

				  struct kvm_mmu_page *page,

				  u64 *spte)

{
@@ -1137,7 +1137,8 @@ static void mmu_pre_write_zap_pte(struct kvm_vcpu *vcpu, 
	*spte = 0;

}



void kvm_mmu_pre_write(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes)

void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,

		       const u8 *old, const u8 *new, int bytes)

{

	gfn_t gfn = gpa >> PAGE_SHIFT;

	struct kvm_mmu_page *page;
@@ -1206,16 +1207,12 @@ void kvm_mmu_pre_write(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes) 
		spte = __va(page->page_hpa);

		spte += page_offset / sizeof(*spte);

		while (npte--) {

			mmu_pre_write_zap_pte(vcpu, page, spte);

			mmu_pte_write_zap_pte(vcpu, page, spte);

			++spte;

		}

	}

}



void kvm_mmu_post_write(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes)

{

}



int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)

{

	gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, gva);