[PATCH 05/18] KVM: MMU: Introduce get_cr3 function pointer

[Joerg Roedel <joerg.roedel@amd.com>]

This function pointer in the MMU context is required to
implement Nested Nested Paging.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/include/asm/kvm_host.h |    1 +
 arch/x86/kvm/mmu.c              |    9 ++++++++-
 arch/x86/kvm/paging_tmpl.h      |    4 ++--
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1bf8501..37d0145 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -242,6 +242,7 @@ struct kvm_pio_request {
 struct kvm_mmu {
 	void (*new_cr3)(struct kvm_vcpu *vcpu);
 	void (*set_cr3)(struct kvm_vcpu *vcpu, unsigned long root);
+	unsigned long (*get_cr3)(struct kvm_vcpu *vcpu);
 	int (*page_fault)(struct kvm_vcpu *vcpu, gva_t gva, u32 err);
 	void (*free)(struct kvm_vcpu *vcpu);
 	gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t gva, u32 access,
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 84e3209..189c68d 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2071,7 +2071,7 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
 	int direct = 0;
 	u64 pdptr;
 
-	root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
+	root_gfn = vcpu->arch.mmu.get_cr3(vcpu) >> PAGE_SHIFT;
 
 	if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
 		hpa_t root = vcpu->arch.mmu.root_hpa;
@@ -2254,6 +2254,11 @@ static void paging_new_cr3(struct kvm_vcpu *vcpu)
 	mmu_free_roots(vcpu);
 }
 
+static unsigned long get_cr3(struct kvm_vcpu *vcpu)
+{
+	return vcpu->arch.cr3;
+}
+
 static void inject_page_fault(struct kvm_vcpu *vcpu,
 			      u64 addr,
 			      u32 err_code)
@@ -2399,6 +2404,7 @@ static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
 	context->root_hpa = INVALID_PAGE;
 	vcpu->arch.mmu.tdp_enabled = true;
 	vcpu->arch.mmu.set_cr3 = kvm_x86_ops->set_tdp_cr3;
+	vcpu->arch.mmu.get_cr3 = get_cr3;
 
 	if (!is_paging(vcpu)) {
 		context->gva_to_gpa = nonpaging_gva_to_gpa;
@@ -2439,6 +2445,7 @@ static int init_kvm_softmmu(struct kvm_vcpu *vcpu)
 	vcpu->arch.mmu.base_role.glevels = vcpu->arch.mmu.root_level;
 	vcpu->arch.mmu.tdp_enabled       = false;
 	vcpu->arch.mmu.set_cr3           = kvm_x86_ops->set_cr3;
+	vcpu->arch.mmu.get_cr3           = get_cr3;
 
 	return r;
 }
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 92b6bb5..1149daa 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -126,7 +126,7 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
 				     fetch_fault);
 walk:
 	walker->level = vcpu->arch.mmu.root_level;
-	pte = vcpu->arch.cr3;
+	pte = vcpu->arch.mmu.get_cr3(vcpu);
 #if PTTYPE == 64
 	if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) {
 		pte = kvm_pdptr_read(vcpu, (addr >> 30) & 3);
@@ -137,7 +137,7 @@ walk:
 	}
 #endif
 	ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
-	       (vcpu->arch.cr3 & CR3_NONPAE_RESERVED_BITS) == 0);
+	       (vcpu->arch.mmu.get_cr3(vcpu) & CR3_NONPAE_RESERVED_BITS) == 0);
 
 	pt_access = ACC_ALL;
 
-- 
1.7.0