KVM: Implement bare minimum of HYPER-V MSRs

Minimum HYPER-V implementation should have GUEST_OS_ID, HYPERCALL and
VP_INDEX MSRs.

[avi: fix build on i386]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Vadim Rozenfeld <vrozenfe@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Gleb Natapov 2010-01-17 15:51:22 +02:00 committed by Marcelo Tosatti
parent 1d5103c11e
commit 55cd8e5a4e
5 changed files with 230 additions and 1 deletions

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@ -413,6 +413,10 @@ struct kvm_arch {
s64 kvmclock_offset;
struct kvm_xen_hvm_config xen_hvm_config;
/* fields used by HYPER-V emulation */
u64 hv_guest_os_id;
u64 hv_hypercall;
};
struct kvm_vm_stat {

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@ -2,6 +2,7 @@
#define _ASM_X86_KVM_PARA_H
#include <linux/types.h>
#include <asm/hyperv.h>
/* This CPUID returns the signature 'KVMKVMKVM' in ebx, ecx, and edx. It
* should be used to determine that a VM is running under KVM.

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@ -55,6 +55,38 @@ TRACE_EVENT(kvm_hypercall,
__entry->a3)
);
/*
* Tracepoint for hypercall.
*/
TRACE_EVENT(kvm_hv_hypercall,
TP_PROTO(__u16 code, bool fast, __u16 rep_cnt, __u16 rep_idx,
__u64 ingpa, __u64 outgpa),
TP_ARGS(code, fast, rep_cnt, rep_idx, ingpa, outgpa),
TP_STRUCT__entry(
__field( __u16, code )
__field( bool, fast )
__field( __u16, rep_cnt )
__field( __u16, rep_idx )
__field( __u64, ingpa )
__field( __u64, outgpa )
),
TP_fast_assign(
__entry->code = code;
__entry->fast = fast;
__entry->rep_cnt = rep_cnt;
__entry->rep_idx = rep_idx;
__entry->ingpa = ingpa;
__entry->outgpa = outgpa;
),
TP_printk("code 0x%x %s cnt 0x%x idx 0x%x in 0x%llx out 0x%llx",
__entry->code, __entry->fast ? "fast" : "slow",
__entry->rep_cnt, __entry->rep_idx, __entry->ingpa,
__entry->outgpa)
);
/*
* Tracepoint for PIO.
*/

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@ -622,9 +622,10 @@ static inline u32 bit(int bitno)
* kvm-specific. Those are put in the beginning of the list.
*/
#define KVM_SAVE_MSRS_BEGIN 2
#define KVM_SAVE_MSRS_BEGIN 4
static u32 msrs_to_save[] = {
MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL,
MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
MSR_K6_STAR,
#ifdef CONFIG_X86_64
@ -1004,6 +1005,74 @@ static int xen_hvm_config(struct kvm_vcpu *vcpu, u64 data)
return r;
}
static bool kvm_hv_hypercall_enabled(struct kvm *kvm)
{
return kvm->arch.hv_hypercall & HV_X64_MSR_HYPERCALL_ENABLE;
}
static bool kvm_hv_msr_partition_wide(u32 msr)
{
bool r = false;
switch (msr) {
case HV_X64_MSR_GUEST_OS_ID:
case HV_X64_MSR_HYPERCALL:
r = true;
break;
}
return r;
}
static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
{
struct kvm *kvm = vcpu->kvm;
switch (msr) {
case HV_X64_MSR_GUEST_OS_ID:
kvm->arch.hv_guest_os_id = data;
/* setting guest os id to zero disables hypercall page */
if (!kvm->arch.hv_guest_os_id)
kvm->arch.hv_hypercall &= ~HV_X64_MSR_HYPERCALL_ENABLE;
break;
case HV_X64_MSR_HYPERCALL: {
u64 gfn;
unsigned long addr;
u8 instructions[4];
/* if guest os id is not set hypercall should remain disabled */
if (!kvm->arch.hv_guest_os_id)
break;
if (!(data & HV_X64_MSR_HYPERCALL_ENABLE)) {
kvm->arch.hv_hypercall = data;
break;
}
gfn = data >> HV_X64_MSR_HYPERCALL_PAGE_ADDRESS_SHIFT;
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return 1;
kvm_x86_ops->patch_hypercall(vcpu, instructions);
((unsigned char *)instructions)[3] = 0xc3; /* ret */
if (copy_to_user((void __user *)addr, instructions, 4))
return 1;
kvm->arch.hv_hypercall = data;
break;
}
default:
pr_unimpl(vcpu, "HYPER-V unimplemented wrmsr: 0x%x "
"data 0x%llx\n", msr, data);
return 1;
}
return 0;
}
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);
return 1;
}
int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
{
switch (msr) {
@ -1118,6 +1187,16 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
pr_unimpl(vcpu, "unimplemented perfctr wrmsr: "
"0x%x data 0x%llx\n", msr, data);
break;
case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
if (kvm_hv_msr_partition_wide(msr)) {
int r;
mutex_lock(&vcpu->kvm->lock);
r = set_msr_hyperv_pw(vcpu, msr, data);
mutex_unlock(&vcpu->kvm->lock);
return r;
} else
return set_msr_hyperv(vcpu, msr, data);
break;
default:
if (msr && (msr == vcpu->kvm->arch.xen_hvm_config.msr))
return xen_hvm_config(vcpu, data);
@ -1217,6 +1296,48 @@ static int get_msr_mce(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
return 0;
}
static int get_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
{
u64 data = 0;
struct kvm *kvm = vcpu->kvm;
switch (msr) {
case HV_X64_MSR_GUEST_OS_ID:
data = kvm->arch.hv_guest_os_id;
break;
case HV_X64_MSR_HYPERCALL:
data = kvm->arch.hv_hypercall;
break;
default:
pr_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
return 1;
}
*pdata = data;
return 0;
}
static int get_msr_hyperv(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
{
u64 data = 0;
switch (msr) {
case HV_X64_MSR_VP_INDEX: {
int r;
struct kvm_vcpu *v;
kvm_for_each_vcpu(r, v, vcpu->kvm)
if (v == vcpu)
data = r;
break;
}
default:
pr_unimpl(vcpu, "Hyper-V unhandled rdmsr: 0x%x\n", msr);
return 1;
}
*pdata = data;
return 0;
}
int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
{
u64 data;
@ -1283,6 +1404,16 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
case MSR_IA32_MCG_STATUS:
case MSR_IA32_MC0_CTL ... MSR_IA32_MC0_CTL + 4 * KVM_MAX_MCE_BANKS - 1:
return get_msr_mce(vcpu, msr, pdata);
case HV_X64_MSR_GUEST_OS_ID ... HV_X64_MSR_SINT15:
if (kvm_hv_msr_partition_wide(msr)) {
int r;
mutex_lock(&vcpu->kvm->lock);
r = get_msr_hyperv_pw(vcpu, msr, pdata);
mutex_unlock(&vcpu->kvm->lock);
return r;
} else
return get_msr_hyperv(vcpu, msr, pdata);
break;
default:
if (!ignore_msrs) {
pr_unimpl(vcpu, "unhandled rdmsr: 0x%x\n", msr);
@ -1398,6 +1529,7 @@ int kvm_dev_ioctl_check_extension(long ext)
case KVM_CAP_XEN_HVM:
case KVM_CAP_ADJUST_CLOCK:
case KVM_CAP_VCPU_EVENTS:
case KVM_CAP_HYPERV:
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
@ -3618,11 +3750,70 @@ static inline gpa_t hc_gpa(struct kvm_vcpu *vcpu, unsigned long a0,
return a0 | ((gpa_t)a1 << 32);
}
int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
{
u64 param, ingpa, outgpa, ret;
uint16_t code, rep_idx, rep_cnt, res = HV_STATUS_SUCCESS, rep_done = 0;
bool fast, longmode;
int cs_db, cs_l;
/*
* hypercall generates UD from non zero cpl and real mode
* per HYPER-V spec
*/
if (kvm_x86_ops->get_cpl(vcpu) != 0 ||
!kvm_read_cr0_bits(vcpu, X86_CR0_PE)) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 0;
}
kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
longmode = is_long_mode(vcpu) && cs_l == 1;
if (!longmode) {
param = (kvm_register_read(vcpu, VCPU_REGS_RDX) << 32) |
(kvm_register_read(vcpu, VCPU_REGS_RAX) & 0xffffff);
ingpa = (kvm_register_read(vcpu, VCPU_REGS_RBX) << 32) |
(kvm_register_read(vcpu, VCPU_REGS_RCX) & 0xffffff);
outgpa = (kvm_register_read(vcpu, VCPU_REGS_RDI) << 32) |
(kvm_register_read(vcpu, VCPU_REGS_RSI) & 0xffffff);
}
#ifdef CONFIG_X86_64
else {
param = kvm_register_read(vcpu, VCPU_REGS_RCX);
ingpa = kvm_register_read(vcpu, VCPU_REGS_RDX);
outgpa = kvm_register_read(vcpu, VCPU_REGS_R8);
}
#endif
code = param & 0xffff;
fast = (param >> 16) & 0x1;
rep_cnt = (param >> 32) & 0xfff;
rep_idx = (param >> 48) & 0xfff;
trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
res = HV_STATUS_INVALID_HYPERCALL_CODE;
ret = res | (((u64)rep_done & 0xfff) << 32);
if (longmode) {
kvm_register_write(vcpu, VCPU_REGS_RAX, ret);
} else {
kvm_register_write(vcpu, VCPU_REGS_RDX, ret >> 32);
kvm_register_write(vcpu, VCPU_REGS_RAX, ret & 0xffffffff);
}
return 1;
}
int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
{
unsigned long nr, a0, a1, a2, a3, ret;
int r = 1;
if (kvm_hv_hypercall_enabled(vcpu->kvm))
return kvm_hv_hypercall(vcpu);
nr = kvm_register_read(vcpu, VCPU_REGS_RAX);
a0 = kvm_register_read(vcpu, VCPU_REGS_RBX);
a1 = kvm_register_read(vcpu, VCPU_REGS_RCX);

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@ -497,6 +497,7 @@ struct kvm_ioeventfd {
#endif
#define KVM_CAP_S390_PSW 42
#define KVM_CAP_PPC_SEGSTATE 43
#define KVM_CAP_HYPERV 44
#ifdef KVM_CAP_IRQ_ROUTING