acrn-hypervisor/hypervisor/arch/x86/guest/hyperv.c

298 lines
7.5 KiB
C

/*
* Microsoft Hyper-V emulation. See Microsoft's
* Hypervisor Top Level Functional Specification for more information.
*
* Copyright (C) 2019 Intel Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <types.h>
#include <asm/guest/vm.h>
#include <logmsg.h>
#include <asm/vmx.h>
#include <asm/guest/hyperv.h>
#include <asm/tsc.h>
#define DBG_LEVEL_HYPERV 6U
/* Partition Reference Counter (HV_X64_MSR_TIME_REF_COUNT) */
#define CPUID3A_TIME_REF_COUNT_MSR (1U << 1U)
/* Hypercall MSRs (HV_X64_MSR_GUEST_OS_ID and HV_X64_MSR_HYPERCALL) */
#define CPUID3A_HYPERCALL_MSR (1U << 5U)
/* Access virtual processor index MSR (HV_X64_MSR_VP_INDEX) */
#define CPUID3A_VP_INDEX_MSR (1U << 6U)
/* Partition reference TSC MSR (HV_X64_MSR_REFERENCE_TSC) */
#define CPUID3A_REFERENCE_TSC_MSR (1U << 9U)
struct HV_REFERENCE_TSC_PAGE {
uint32_t tsc_sequence;
uint32_t reserved1;
uint64_t tsc_scale;
uint64_t tsc_offset;
uint64_t reserved2[509];
};
static inline uint64_t
u64_shl64_div_u64(uint64_t a, uint64_t divisor)
{
uint64_t ret, tmp;
asm volatile ("divq %2" :
"=a" (ret), "=d" (tmp) :
"rm" (divisor), "0" (0U), "1" (a));
return ret;
}
static inline uint64_t
u64_mul_u64_shr64(uint64_t a, uint64_t b)
{
uint64_t ret, disc;
asm volatile ("mulq %3" :
"=d" (ret), "=a" (disc) :
"a" (a), "r" (b));
return ret;
}
static void
hyperv_setup_tsc_page(const struct acrn_vcpu *vcpu, uint64_t val)
{
union hyperv_ref_tsc_page_msr *ref_tsc_page = &vcpu->vm->arch_vm.hyperv.ref_tsc_page;
struct HV_REFERENCE_TSC_PAGE *p;
uint32_t tsc_seq;
ref_tsc_page->val64 = val;
if (ref_tsc_page->enabled == 1U) {
p = (struct HV_REFERENCE_TSC_PAGE *)gpa2hva(vcpu->vm, ref_tsc_page->gpfn << PAGE_SHIFT);
if (p != NULL) {
stac();
p->tsc_scale = vcpu->vm->arch_vm.hyperv.tsc_scale;
p->tsc_offset = vcpu->vm->arch_vm.hyperv.tsc_offset;
cpu_write_memory_barrier();
tsc_seq = p->tsc_sequence + 1U;
if ((tsc_seq == 0xFFFFFFFFU) || (tsc_seq == 0U)) {
tsc_seq = 1U;
}
p->tsc_sequence = tsc_seq;
clac();
}
}
}
static inline uint64_t
hyperv_scale_tsc(uint64_t scale)
{
uint64_t tsc;
tsc = rdtsc() + exec_vmread64(VMX_TSC_OFFSET_FULL);
return u64_mul_u64_shr64(tsc, scale);
}
static inline uint64_t
hyperv_get_ReferenceTime(struct acrn_vm *vm)
{
return hyperv_scale_tsc(vm->arch_vm.hyperv.tsc_scale) - vm->arch_vm.hyperv.tsc_offset;
}
static void
hyperv_setup_hypercall_page(const struct acrn_vcpu *vcpu, uint64_t val)
{
union hyperv_hypercall_msr hypercall;
uint64_t page_gpa;
void *page_hva;
/*
* All enlightened versions of Windows operating systems invoke guest hypercalls on
* the basis of the recommendations presented by the hypervisor in CPUID.40000004:EAX.
* A conforming hypervisor must return HV_STATUS_INVALID_HYPERCALL_CODE for any
* unimplemented hypercalls.
* ACRN does not wish to handle any hypercalls at moment, the following hypercall
* code page is implemented for this purpose.
* inst32[] for 32 bits:
* mov eax, 0x02 ; HV_STATUS_INVALID_HYPERCALL_CODE
* mov edx, 0
* ret
* inst64[] for 64 bits:
* mov rax, 0x02 ; HV_STATUS_INVALID_HYPERCALL_CODE
* ret
*/
const uint8_t inst32[11] = {0xb8U, 0x02U, 0x0U, 0x0U, 0x0U, 0xbaU, 0x0U, 0x0U, 0x0U, 0x0U, 0xc3U};
const uint8_t inst64[8] = {0x48U, 0xc7U, 0xc0U, 0x02U, 0x0U, 0x0U, 0x0U, 0xc3U};
hypercall.val64 = val;
if (hypercall.enabled != 0UL) {
page_gpa = hypercall.gpfn << PAGE_SHIFT;
page_hva = gpa2hva(vcpu->vm, page_gpa);
if (page_hva != NULL) {
stac();
(void)memset(page_hva, 0U, PAGE_SIZE);
if (get_vcpu_mode(vcpu) == CPU_MODE_64BIT) {
(void)memcpy_s(page_hva, 8U, inst64, 8U);
} else {
(void)memcpy_s(page_hva, 11U, inst32, 11U);
}
clac();
}
}
}
int32_t
hyperv_wrmsr(struct acrn_vcpu *vcpu, uint32_t msr, uint64_t wval)
{
int32_t ret = 0;
switch (msr) {
case HV_X64_MSR_GUEST_OS_ID:
vcpu->vm->arch_vm.hyperv.guest_os_id.val64 = wval;
if (wval == 0UL) {
vcpu->vm->arch_vm.hyperv.hypercall_page.enabled = 0UL;
}
break;
case HV_X64_MSR_HYPERCALL:
if (vcpu->vm->arch_vm.hyperv.guest_os_id.val64 == 0UL) {
pr_warn("hv: %s: guest_os_id is 0", __func__);
break;
}
vcpu->vm->arch_vm.hyperv.hypercall_page.val64 = wval;
hyperv_setup_hypercall_page(vcpu, wval);
break;
case HV_X64_MSR_REFERENCE_TSC:
hyperv_setup_tsc_page(vcpu, wval);
break;
case HV_X64_MSR_VP_INDEX:
case HV_X64_MSR_TIME_REF_COUNT:
/* read only */
/* fallthrough */
default:
pr_err("hv: %s: unexpected MSR[0x%x] write", __func__, msr);
ret = -1;
break;
}
dev_dbg(DBG_LEVEL_HYPERV, "hv: %s: MSR=0x%x wval=0x%lx vcpuid=%d vmid=%d",
__func__, msr, wval, vcpu->vcpu_id, vcpu->vm->vm_id);
return ret;
}
int32_t
hyperv_rdmsr(struct acrn_vcpu *vcpu, uint32_t msr, uint64_t *rval)
{
int32_t ret = 0;
switch (msr) {
case HV_X64_MSR_GUEST_OS_ID:
*rval = vcpu->vm->arch_vm.hyperv.guest_os_id.val64;
break;
case HV_X64_MSR_HYPERCALL:
*rval = vcpu->vm->arch_vm.hyperv.hypercall_page.val64;
break;
case HV_X64_MSR_VP_INDEX:
*rval = vcpu->vcpu_id;
break;
case HV_X64_MSR_TIME_REF_COUNT:
*rval = hyperv_get_ReferenceTime(vcpu->vm);
break;
case HV_X64_MSR_REFERENCE_TSC:
*rval = vcpu->vm->arch_vm.hyperv.ref_tsc_page.val64;
break;
default:
pr_err("hv: %s: unexpected MSR[0x%x] read", __func__, msr);
ret = -1;
break;
}
dev_dbg(DBG_LEVEL_HYPERV, "hv: %s: MSR=0x%x rval=0x%lx vcpuid=%d vmid=%d",
__func__, msr, *rval, vcpu->vcpu_id, vcpu->vm->vm_id);
return ret;
}
void
hyperv_init_time(struct acrn_vm *vm)
{
uint64_t tsc_scale, tsc_khz = get_tsc_khz();
uint64_t tsc_offset;
/*
* The partition reference time is computed by the following formula:
* ReferenceTime = ((VirtualTsc * TscScale) >> 64) + TscOffset
* ReferenceTime is in 100ns units
*
* ReferenceTime =
* VirtualTsc / (get_tsc_khz() * 1000) * 1000000000 / 100
* + TscOffset
*
* TscScale = (10000U << 64U) / get_tsc_khz()
*/
tsc_scale = u64_shl64_div_u64(10000U, tsc_khz);
tsc_offset = hyperv_scale_tsc(tsc_scale);
vm->arch_vm.hyperv.tsc_scale = tsc_scale;
vm->arch_vm.hyperv.tsc_offset = tsc_offset;
dev_dbg(DBG_LEVEL_HYPERV, "%s, tsc_scale = 0x%lx, tsc_offset = %ld",
__func__, tsc_scale, tsc_offset);
}
void
hyperv_init_vcpuid_entry(uint32_t leaf, uint32_t subleaf, uint32_t flags,
struct vcpuid_entry *entry)
{
entry->leaf = leaf;
entry->subleaf = subleaf;
entry->flags = flags;
switch (leaf) {
case 0x40000001U: /* HV interface version */
entry->eax = 0x31237648U; /* "Hv#1" */
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
case 0x40000002U: /* HV system identity */
entry->eax = 0U;
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
case 0x40000003U: /* HV supported feature */
entry->eax = CPUID3A_HYPERCALL_MSR | CPUID3A_VP_INDEX_MSR |
CPUID3A_TIME_REF_COUNT_MSR | CPUID3A_REFERENCE_TSC_MSR;
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
case 0x40000004U: /* HV Recommended hypercall usage */
entry->eax = 0U;
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
case 0x40000005U: /* HV Maximum Supported Virtual & logical Processors */
entry->eax = MAX_VCPUS_PER_VM;
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
case 0x40000006U: /* Implementation Hardware Features */
entry->eax = 0U;
entry->ebx = 0U;
entry->ecx = 0U;
entry->edx = 0U;
break;
default:
/* do nothing */
break;
}
dev_dbg(DBG_LEVEL_HYPERV, "hv: %s: leaf=%x subleaf=%x flags=%x eax=%x ebx=%x ecx=%x edx=%x",
__func__, leaf, subleaf, flags, entry->eax, entry->ebx, entry->ecx, entry->edx);
}