[PATCHv2,3/4] Add HYPER-V apic access MSRs.

Commit Message

Gleb Natapov Jan. 17, 2010, 9:03 a.m. UTC

None

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 67d19e4..a1f0b5d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -363,6 +363,8 @@  struct kvm_vcpu_arch {
 	/* used for guest single stepping over the given code position */
 	u16 singlestep_cs;
 	unsigned long singlestep_rip;
+	/* fields used by HYPER-V emulation */
+	u64 hv_vapic;
 };
 
 struct kvm_mem_alias {
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ba8c045..4b224f9 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1246,3 +1246,34 @@  int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
 
 	return 0;
 }
+
+int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
+{
+	struct kvm_lapic *apic = vcpu->arch.apic;
+
+	if (!irqchip_in_kernel(vcpu->kvm))
+		return 1;
+
+	/* if this is ICR write vector before command */
+	if (reg == APIC_ICR)
+		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
+	return apic_reg_write(apic, reg, (u32)data);
+}
+
+int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
+{
+	struct kvm_lapic *apic = vcpu->arch.apic;
+	u32 low, high = 0;
+
+	if (!irqchip_in_kernel(vcpu->kvm))
+		return 1;
+
+	if (apic_reg_read(apic, reg, 4, &low))
+		return 1;
+	if (reg == APIC_ICR)
+		apic_reg_read(apic, APIC_ICR2, 4, &high);
+
+	*data = (((u64)high) << 32) | low;
+
+	return 0;
+}
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 40010b0..d081cb6 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -48,4 +48,12 @@  void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu);
 
 int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data);
 int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data);
+
+int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data);
+int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data);
+
+static inline bool kvm_hv_vapic_enabled(struct kvm_vcpu *vcpu)
+{
+	return !!(vcpu->arch.hv_vapic & HV_X64_MSR_APIC_ASSIST_PAGE_ENABLE);
+}
 #endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index db0b2b1..2fe555c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -632,6 +632,7 @@  static u32 msrs_to_save[] = {
 #endif
 	MSR_IA32_TSC, MSR_IA32_PERF_STATUS, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA,
 	HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
+	HV_X64_MSR_APIC_ASSIST_PAGE,
 };
 
 static unsigned num_msrs_to_save;
@@ -1063,10 +1064,37 @@  static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 
 static int set_msr_hyperv(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 {
-	pr_unimpl(vcpu, "HYPER-V unimplemented wrmsr: 0x%x data 0x%llx\n",
-		  msr, data);
+	switch (msr) {
+	case HV_X64_MSR_APIC_ASSIST_PAGE: {
+		unsigned long vaddr;
+		void *addr;
+		struct page *page;
+		vcpu->arch.hv_vapic = data;
+		if (!kvm_hv_vapic_enabled(vcpu))
+			break;
+		vaddr = gfn_to_hva(vcpu->kvm, data >>
+				  HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_SHIFT);
+		if (kvm_is_error_hva(vaddr))
+			return 1;
+		page = virt_to_page(vaddr);
+		addr = kmap_atomic(page, KM_USER0);
+		clear_user_page(addr, vaddr, page);
+		kunmap_atomic(addr, KM_USER0);
+		break;
+	}
+	case HV_X64_MSR_EOI:
+		return kvm_hv_vapic_msr_write(vcpu, APIC_EOI, data);
+	case HV_X64_MSR_ICR:
+		return kvm_hv_vapic_msr_write(vcpu, APIC_ICR, data);
+	case HV_X64_MSR_TPR:
+		return kvm_hv_vapic_msr_write(vcpu, APIC_TASKPRI, data);
+	default:
+		pr_unimpl(vcpu, "HYPER-V unimplemented wrmsr: 0x%x "
+			  "data 0x%llx\n", msr, data);
+		return 1;
+	}
 
-	return 1;
+	return 0;
 }
 
 int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
@@ -1326,6 +1354,12 @@  static int get_msr_hyperv(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
 				data = r;
 		break;
 	}
+	case HV_X64_MSR_EOI:
+		return kvm_hv_vapic_msr_read(vcpu, APIC_EOI, pdata);
+	case HV_X64_MSR_ICR:
+		return kvm_hv_vapic_msr_read(vcpu, APIC_ICR, pdata);
+	case HV_X64_MSR_TPR:
+		return kvm_hv_vapic_msr_read(vcpu, APIC_TASKPRI, pdata);
 	default:
 		pr_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
 		return 1;
@@ -1526,6 +1560,7 @@  int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_ADJUST_CLOCK:
 	case KVM_CAP_VCPU_EVENTS:
 	case KVM_CAP_HYPERV:
+	case KVM_CAP_HYPERV_VAPIC:
 		r = 1;
 		break;
 	case KVM_CAP_COALESCED_MMIO:
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index e227cba..5ce6173 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -498,6 +498,7 @@  struct kvm_ioeventfd {
 #define KVM_CAP_S390_PSW 42
 #define KVM_CAP_PPC_SEGSTATE 43
 #define KVM_CAP_HYPERV 44
+#define KVM_CAP_HYPERV_VAPIC 45
 
 #ifdef KVM_CAP_IRQ_ROUTING