KVM: MMU: Implement nested gva_to_gpa functions
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>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1b3eb8a..8ec3547 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -296,6 +296,16 @@
struct kvm_mmu mmu;
/*
+ * Paging state of an L2 guest (used for nested npt)
+ *
+ * This context will save all necessary information to walk page tables
+ * of the an L2 guest. This context is only initialized for page table
+ * walking and not for faulting since we never handle l2 page faults on
+ * the host.
+ */
+ struct kvm_mmu nested_mmu;
+
+ /*
* Pointer to the mmu context currently used for
* gva_to_gpa translations.
*/
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index cb06ada..1e215e8 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2466,6 +2466,14 @@
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, access);
+}
+
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 a704a81..eefe363 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -276,6 +276,16 @@
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 *sp,
u64 *spte, const void *pte)
{
@@ -660,6 +670,27 @@
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)
{
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 2d6385e..bf4dc2f 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -50,6 +50,11 @@
#endif
}
+static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;
+}
+
static inline int is_pae(struct kvm_vcpu *vcpu)
{
return kvm_read_cr4_bits(vcpu, X86_CR4_PAE);