[PATCH 12/22] KVM: MMU: Implement nested gva_to_gpa functions

Joerg Roedel
2010-04-27T10:38:22Z

This patch adds the functions to do a nested l2_gva to
l1_gpa page table walk.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/include/asm/kvm_host.h | 4 ++++
arch/x86/kvm/mmu.c | 8 ++++++++
arch/x86/kvm/paging_tmpl.h | 31 +++++++++++++++++++++++++++++++
3 files changed, 43 insertions(+), 0 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ccdbd2f..3cbfb51 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -287,6 +287,10 @@ struct kvm_vcpu_arch {
bool tpr_access_reporting;

struct kvm_mmu mmu;
+
+ /* Used for two dimensional paging emulation */
+ struct kvm_mmu nested_mmu;
+
/* only needed in kvm_pv_mmu_op() path, but it's hot so
* put it here to avoid allocation */
struct kvm_pv_mmu_op_buffer mmu_op_buffer;
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4e0bfdb..8bd40b5 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2144,6 +2144,14 @@ static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr,
return vaddr;
}

+static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gva_t vaddr,
+ u32 access, u32 *error)
+{
+ if (error)
+ *error = 0;
+ return vcpu->arch.nested_mmu.translate_gpa(vcpu, vaddr, error);
+}
+
static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
u32 error_code)
{
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 101849a..7819a6f 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -264,6 +264,16 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
write_fault, user_fault, fetch_fault);
}

+static int FNAME(walk_addr_nested)(struct guest_walker *walker,
+ struct kvm_vcpu *vcpu, gva_t addr,
+ int write_fault, int user_fault,
+ int fetch_fault)
+{
+ return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.nested_mmu,
+ addr, write_fault, user_fault,
+ fetch_fault);
+}
+
static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
u64 *spte, const void *pte)
{
@@ -544,6 +554,27 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access,
return gpa;
}

+static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gva_t vaddr,
+ u32 access, u32 *error)
+{
+ struct guest_walker walker;
+ gpa_t gpa = UNMAPPED_GVA;
+ int r;
+
+ r = FNAME(walk_addr_nested)(&walker, vcpu, vaddr,
+ !!(access & PFERR_WRITE_MASK),
+ !!(access & PFERR_USER_MASK),
+ !!(access & PFERR_FETCH_MASK));
+
+ if (r) {
+ gpa = gfn_to_gpa(walker.gfn);
+ gpa |= vaddr & ~PAGE_MASK;
+ } else if (error)
+ *error = walker.error_code;
+
+ return gpa;
+}
+
static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *sp)
{
--
1.7.0.4