From: David Woodhouse <dwmw@amazon.co.uk>
Date: Fri, 11 Mar 2022 20:01:51 +0000 (+0000)
Subject: KVM: x86/xen: Implement HVMOP_flush_tlbs
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=6cdca779dcc521ccb0e0ec1397fd5dbd2bc55c40;p=users%2Fdwmw2%2Flinux.git

KVM: x86/xen: Implement HVMOP_flush_tlbs

AFAICT there isn't a way for the VMM to do this from userspace.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---

diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 7e7c8a5bff52a..e031a29ed0a9b 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -1212,6 +1212,12 @@ static bool kvm_xen_hcall_set_timer_op(struct kvm_vcpu *vcpu, uint64_t timeout,
 	return true;
 }
 
+static bool kvm_xen_hcall_hvm_flush_tlbs(struct kvm_vcpu *vcpu)
+{
+	kvm_flush_remote_tlbs(vcpu->kvm);
+	return true;
+}
+
 int kvm_xen_hypercall(struct kvm_vcpu *vcpu)
 {
 	bool longmode;
@@ -1266,6 +1272,10 @@ int kvm_xen_hypercall(struct kvm_vcpu *vcpu)
 		handled = kvm_xen_hcall_vcpu_op(vcpu, longmode, params[0], params[1],
 						params[2], &r);
 		break;
+	case __HYPERVISOR_hvm_op:
+		if (params[0] == HVMOP_flush_tlbs)
+			handled = kvm_xen_hcall_hvm_flush_tlbs(vcpu);
+		break;
 	case __HYPERVISOR_set_timer_op: {
 		u64 timeout = params[0];
 		/* In 32-bit mode, the 64-bit timeout is in two 32-bit params. */
diff --git a/arch/x86/kvm/xen.h b/arch/x86/kvm/xen.h
index ee5c4ae0755cd..414133c329038 100644
--- a/arch/x86/kvm/xen.h
+++ b/arch/x86/kvm/xen.h
@@ -205,4 +205,8 @@ struct compat_vcpu_runstate_info {
     uint64_t time[4];
 } __attribute__((packed));
 
+#ifndef HVMOP_flush_tlbs
+#define HVMOP_flush_tlbs	5
+#endif
+
 #endif /* __ARCH_X86_KVM_XEN_H__ */