[PATCH v2 7/9] KVM: x86/mmu: Add try_get_mt_mask to x86_ops

[Ben Gardon]

Add another function for getting the memory type mask to x86_ops.
This version of the function can fail, but it does not require a vCPU
pointer. It will be used in a subsequent commit for in-place large page
promotion when disabling dirty logging.

No functional change intended.

Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>
---
 arch/x86/include/asm/kvm-x86-ops.h | 1 +
 arch/x86/include/asm/kvm_host.h    | 2 ++
 arch/x86/kvm/svm/svm.c             | 9 +++++++++
 arch/x86/kvm/vmx/vmx.c             | 1 +
 4 files changed, 13 insertions(+)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 29affccb353c..29880363b5ed 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -88,6 +88,7 @@ KVM_X86_OP_OPTIONAL(sync_pir_to_irr)
 KVM_X86_OP_OPTIONAL_RET0(set_tss_addr)
 KVM_X86_OP_OPTIONAL_RET0(set_identity_map_addr)
 KVM_X86_OP_OPTIONAL_RET0(get_mt_mask)
+KVM_X86_OP(try_get_mt_mask)
 KVM_X86_OP(load_mmu_pgd)
 KVM_X86_OP(has_wbinvd_exit)
 KVM_X86_OP(get_l2_tsc_offset)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f72e80178ffc..a114e4782702 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1422,6 +1422,8 @@ struct kvm_x86_ops {
 	int (*set_tss_addr)(struct kvm *kvm, unsigned int addr);
 	int (*set_identity_map_addr)(struct kvm *kvm, u64 ident_addr);
 	u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
+	bool (*try_get_mt_mask)(struct kvm *kvm, gfn_t gfn,
+				bool is_mmio, u64 *mask);
 
 	void (*load_mmu_pgd)(struct kvm_vcpu *vcpu, hpa_t root_hpa,
 			     int root_level);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index b069493ad5c7..e73415dfcf52 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3944,6 +3944,13 @@ static bool svm_has_emulated_msr(struct kvm *kvm, u32 index)
 	return true;
 }
 
+static bool svm_try_get_mt_mask(struct kvm *kvm, gfn_t gfn,
+				bool is_mmio, u64 *mask)
+{
+	*mask = 0;
+	return true;
+}
+
 static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -4600,6 +4607,8 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.check_apicv_inhibit_reasons = avic_check_apicv_inhibit_reasons,
 	.apicv_post_state_restore = avic_apicv_post_state_restore,
 
+	.try_get_mt_mask = svm_try_get_mt_mask,
+
 	.get_exit_info = svm_get_exit_info,
 
 	.vcpu_after_set_cpuid = svm_vcpu_after_set_cpuid,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 69c654567475..81e9805ed1d8 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7813,6 +7813,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
 	.set_tss_addr = vmx_set_tss_addr,
 	.set_identity_map_addr = vmx_set_identity_map_addr,
 	.get_mt_mask = vmx_get_mt_mask,
+	.try_get_mt_mask = vmx_try_get_mt_mask,
 
 	.get_exit_info = vmx_get_exit_info,
 
-- 
2.35.1.894.gb6a874cedc-goog