Commit fb72d167 authored by Joerg Roedel's avatar Joerg Roedel Committed by Avi Kivity
Browse files

KVM: MMU: add TDP support to the KVM MMU 



This patch contains the changes to the KVM MMU necessary for support of the
Nested Paging feature in AMD Barcelona and Phenom Processors.

Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent cc4b6871

arch/x86/kvm/mmu.c

+76 −3
Original line number Diff line number Diff line
@@ -1097,6 +1097,7 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) 
	int i;

	gfn_t root_gfn;

	struct kvm_mmu_page *sp;

	int metaphysical = 0;



	root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
@@ -1105,14 +1106,20 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) 
		hpa_t root = vcpu->arch.mmu.root_hpa;



		ASSERT(!VALID_PAGE(root));

		if (tdp_enabled)

			metaphysical = 1;

		sp = kvm_mmu_get_page(vcpu, root_gfn, 0,

				      PT64_ROOT_LEVEL, 0, ACC_ALL, NULL);

				      PT64_ROOT_LEVEL, metaphysical,

				      ACC_ALL, NULL);

		root = __pa(sp->spt);

		++sp->root_count;

		vcpu->arch.mmu.root_hpa = root;

		return;

	}

#endif

	metaphysical = !is_paging(vcpu);

	if (tdp_enabled)

		metaphysical = 1;

	for (i = 0; i < 4; ++i) {

		hpa_t root = vcpu->arch.mmu.pae_root[i];
@@ -1126,7 +1133,7 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu) 
		} else if (vcpu->arch.mmu.root_level == 0)

			root_gfn = 0;

		sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30,

				      PT32_ROOT_LEVEL, !is_paging(vcpu),

				      PT32_ROOT_LEVEL, metaphysical,

				      ACC_ALL, NULL);

		root = __pa(sp->spt);

		++sp->root_count;
@@ -1160,6 +1167,36 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, 
			     error_code & PFERR_WRITE_MASK, gfn);

}



static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa,

				u32 error_code)

{

	struct page *page;

	int r;



	ASSERT(vcpu);

	ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));



	r = mmu_topup_memory_caches(vcpu);

	if (r)

		return r;



	down_read(&current->mm->mmap_sem);

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

	if (is_error_page(page)) {

		kvm_release_page_clean(page);

		up_read(&current->mm->mmap_sem);

		return 1;

	}

	spin_lock(&vcpu->kvm->mmu_lock);

	kvm_mmu_free_some_pages(vcpu);

	r = __direct_map(vcpu, gpa, error_code & PFERR_WRITE_MASK,

			 gpa >> PAGE_SHIFT, page, TDP_ROOT_LEVEL);

	spin_unlock(&vcpu->kvm->mmu_lock);

	up_read(&current->mm->mmap_sem);



	return r;

}



static void nonpaging_free(struct kvm_vcpu *vcpu)

{

	mmu_free_roots(vcpu);
@@ -1253,7 +1290,35 @@ static int paging32E_init_context(struct kvm_vcpu *vcpu) 
	return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL);

}



static int init_kvm_mmu(struct kvm_vcpu *vcpu)

static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)

{

	struct kvm_mmu *context = &vcpu->arch.mmu;



	context->new_cr3 = nonpaging_new_cr3;

	context->page_fault = tdp_page_fault;

	context->free = nonpaging_free;

	context->prefetch_page = nonpaging_prefetch_page;

	context->shadow_root_level = TDP_ROOT_LEVEL;

	context->root_hpa = INVALID_PAGE;



	if (!is_paging(vcpu)) {

		context->gva_to_gpa = nonpaging_gva_to_gpa;

		context->root_level = 0;

	} else if (is_long_mode(vcpu)) {

		context->gva_to_gpa = paging64_gva_to_gpa;

		context->root_level = PT64_ROOT_LEVEL;

	} else if (is_pae(vcpu)) {

		context->gva_to_gpa = paging64_gva_to_gpa;

		context->root_level = PT32E_ROOT_LEVEL;

	} else {

		context->gva_to_gpa = paging32_gva_to_gpa;

		context->root_level = PT32_ROOT_LEVEL;

	}



	return 0;

}



static int init_kvm_softmmu(struct kvm_vcpu *vcpu)

{

	ASSERT(vcpu);

	ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
@@ -1268,6 +1333,14 @@ static int init_kvm_mmu(struct kvm_vcpu *vcpu) 
		return paging32_init_context(vcpu);

}



static int init_kvm_mmu(struct kvm_vcpu *vcpu)

{

	if (tdp_enabled)

		return init_kvm_tdp_mmu(vcpu);

	else

		return init_kvm_softmmu(vcpu);

}



static void destroy_kvm_mmu(struct kvm_vcpu *vcpu)

{

	ASSERT(vcpu);

arch/x86/kvm/mmu.h

+6 −0
Original line number Diff line number Diff line
@@ -3,6 +3,12 @@ 


#include <linux/kvm_host.h>



#ifdef CONFIG_X86_64

#define TDP_ROOT_LEVEL PT64_ROOT_LEVEL

#else

#define TDP_ROOT_LEVEL PT32E_ROOT_LEVEL

#endif



static inline void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)

{

	if (unlikely(vcpu->kvm->arch.n_free_mmu_pages < KVM_MIN_FREE_MMU_PAGES))