From: Gleb Natapov <gleb@xxxxxxxxxx>
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@xxxxxxxxxx>
Signed-off-by: Vadim Rozenfeld <vrozenfe@xxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 4 +
arch/x86/include/asm/kvm_para.h | 1 +
arch/x86/kvm/trace.h | 32 +++++++
arch/x86/kvm/x86.c | 193 ++++++++++++++++++++++++++++++++++++++-
include/linux/kvm.h | 1 +
5 files changed, 230 insertions(+), 1 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 93bee7a..67d19e4 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -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 {
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index c584076..ffae142 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -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.
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 816e044..1cb3d0e 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -56,6 +56,38 @@ TRACE_EVENT(kvm_hypercall,
);
/*
+ * 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.
*/
TRACE_EVENT(kvm_pio,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1ad34d1..480137d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -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 @@ out:
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);
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index f2feef6..e227cba 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -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
--
1.6.5.3
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