[PATCH v2 3/5] LoongArch: KVM: Add separate vmid feature support

[Bibo Mao]

Feature cpu_has_guestid is used to check whether separate vmid/vpid
is supported or not. It is disabled by default, add this feature
checking, there is no function change.

Signed-off-by: Bibo Mao <maobibo@xxxxxxxxxxx>
---
 arch/loongarch/kvm/main.c | 14 +++++++++-----
 arch/loongarch/kvm/mmu.c  |  6 ++++--
 arch/loongarch/kvm/vcpu.c |  3 ++-
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
index ac804e77e844..c36e62ab0d91 100644
--- a/arch/loongarch/kvm/main.c
+++ b/arch/loongarch/kvm/main.c
@@ -218,7 +218,8 @@ static void kvm_update_vpid(struct kvm_vcpu *vcpu, int cpu)
 		++vpid; /* vpid 0 reserved for root */
 
 		/* start new vpid cycle */
-		kvm_flush_tlb_all();
+		if (!cpu_has_guestid)
+			kvm_flush_tlb_all();
 	}
 
 	context->vpid_cache = vpid;
@@ -282,10 +283,13 @@ static void __kvm_check_vmid(struct kvm_vcpu *vcpu)
 {
 	unsigned long vmid;
 
-	vmid = vcpu->arch.vpid & vpid_mask;
-	if (vcpu->arch.hw_vmid != vmid) {
-		vcpu->arch.hw_vmid = vcpu->arch.vpid & vpid_mask;
-		kvm_clear_request(KVM_REQ_TLB_FLUSH_GPA, vcpu);
+	/* On some machines like 3A5000, vmid needs the same with vpid */
+	if (!cpu_has_guestid) {
+		vmid = vcpu->arch.vpid & vpid_mask;
+		if (vcpu->arch.hw_vmid != vmid) {
+			vcpu->arch.hw_vmid = vcpu->arch.vpid & vpid_mask;
+			kvm_clear_request(KVM_REQ_TLB_FLUSH_GPA, vcpu);
+		}
 	}
 }
 
diff --git a/arch/loongarch/kvm/mmu.c b/arch/loongarch/kvm/mmu.c
index e104897aa532..714640a2e614 100644
--- a/arch/loongarch/kvm/mmu.c
+++ b/arch/loongarch/kvm/mmu.c
@@ -929,8 +929,10 @@ int kvm_handle_mm_fault(struct kvm_vcpu *vcpu, unsigned long gpa, bool write, in
 		 *
 		 * With SW PTW, invalid TLB is added in TLB refill exception.
 		 */
-		vcpu->arch.flush_gpa = gpa;
-		kvm_make_request(KVM_REQ_TLB_FLUSH_GPA, vcpu);
+		if (!cpu_has_guestid) {
+			vcpu->arch.flush_gpa = gpa;
+			kvm_make_request(KVM_REQ_TLB_FLUSH_GPA, vcpu);
+		}
 	}
 
 	return 0;
diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index 20c207d80e31..0b2355aec932 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -210,7 +210,8 @@ static int kvm_check_requests(struct kvm_vcpu *vcpu)
 		return RESUME_GUEST;
 
 	if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu))
-		vcpu->arch.vpid = 0;  /* Drop vpid for this vCPU */
+		if (!cpu_has_guestid)
+			vcpu->arch.vpid = 0;  /* Drop vpid for this vCPU */
 
 	if (kvm_dirty_ring_check_request(vcpu))
 		return RESUME_HOST;
-- 
2.39.3