target-i386/kvm: Hyper-V SynIC timers MSR's support

Hyper-V SynIC timers are host timers that are configurable
by guest through corresponding MSR's (HV_X64_MSR_STIMER*).
Guest setup and use fired by host events(SynIC interrupt
and appropriate timer expiration message) as guest clock
events.

The state of Hyper-V SynIC timers are stored in corresponding
MSR's. This patch seria implements such MSR's support and migration.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: kvm@vger.kernel.org

Message-Id: <1448464885-8300-3-git-send-email-asmetanin@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

5 files changed, 82 insertions, 1 deletions

diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h
index 7ea5b34166..5f9d960b25 100644
--- a/target-i386/cpu-qom.h
+++ b/target-i386/cpu-qom.h
@@ -95,6 +95,7 @@ typedef struct X86CPU {
     bool hyperv_vpindex;
     bool hyperv_runtime;
     bool hyperv_synic;
+    bool hyperv_stimer;
     bool check_cpuid;
     bool enforce_cpuid;
     bool expose_kvm;
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 2fdd855158..92f7cc1f7d 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -3147,6 +3147,7 @@ static Property x86_cpu_properties[] = {
     DEFINE_PROP_BOOL("hv-vpindex", X86CPU, hyperv_vpindex, false),
     DEFINE_PROP_BOOL("hv-runtime", X86CPU, hyperv_runtime, false),
     DEFINE_PROP_BOOL("hv-synic", X86CPU, hyperv_synic, false),
+    DEFINE_PROP_BOOL("hv-stimer", X86CPU, hyperv_stimer, false),
     DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true),
     DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false),
     DEFINE_PROP_BOOL("kvm", X86CPU, expose_kvm, true),
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index 1168ddf26b..595891e78d 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -925,6 +925,8 @@ typedef struct CPUX86State {
     uint64_t msr_hv_synic_evt_page;
     uint64_t msr_hv_synic_msg_page;
     uint64_t msr_hv_synic_sint[HV_SYNIC_SINT_COUNT];
+    uint64_t msr_hv_stimer_config[HV_SYNIC_STIMER_COUNT];
+    uint64_t msr_hv_stimer_count[HV_SYNIC_STIMER_COUNT];
 
     /* exception/interrupt handling */
     int error_code;
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index d1c2c819da..7692b5984d 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -90,6 +90,7 @@ static bool has_msr_hv_reset;
 static bool has_msr_hv_vpindex;
 static bool has_msr_hv_runtime;
 static bool has_msr_hv_synic;
+static bool has_msr_hv_stimer;
 static bool has_msr_mtrr;
 static bool has_msr_xss;
 
@@ -526,7 +527,8 @@ static bool hyperv_enabled(X86CPU *cpu)
             cpu->hyperv_reset ||
             cpu->hyperv_vpindex ||
             cpu->hyperv_runtime ||
-            cpu->hyperv_synic);
+            cpu->hyperv_synic ||
+            cpu->hyperv_stimer);
 }
 
 static Error *invtsc_mig_blocker;
@@ -630,6 +632,13 @@ int kvm_arch_init_vcpu(CPUState *cs)
                 env->msr_hv_synic_sint[sint] = HV_SYNIC_SINT_MASKED;
             }
         }
+        if (cpu->hyperv_stimer) {
+            if (!has_msr_hv_stimer) {
+                fprintf(stderr, "Hyper-V timers aren't supported by kernel\n");
+                return -ENOSYS;
+            }
+            c->eax |= HV_X64_MSR_SYNTIMER_AVAILABLE;
+        }
         c = &cpuid_data.entries[cpuid_i++];
         c->function = HYPERV_CPUID_ENLIGHTMENT_INFO;
         if (cpu->hyperv_relaxed_timing) {
@@ -980,6 +989,10 @@ static int kvm_get_supported_msrs(KVMState *s)
                     has_msr_hv_synic = true;
                     continue;
                 }
+                if (kvm_msr_list->indices[i] == HV_X64_MSR_STIMER0_CONFIG) {
+                    has_msr_hv_stimer = true;
+                    continue;
+                }
             }
         }
 
@@ -1558,6 +1571,19 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
                                   env->msr_hv_synic_sint[j]);
             }
         }
+        if (has_msr_hv_stimer) {
+            int j;
+
+            for (j = 0; j < ARRAY_SIZE(env->msr_hv_stimer_config); j++) {
+                kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_STIMER0_CONFIG + j*2,
+                                env->msr_hv_stimer_config[j]);
+            }
+
+            for (j = 0; j < ARRAY_SIZE(env->msr_hv_stimer_count); j++) {
+                kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_STIMER0_COUNT + j*2,
+                                env->msr_hv_stimer_count[j]);
+            }
+        }
         if (has_msr_mtrr) {
             kvm_msr_entry_set(&msrs[n++], MSR_MTRRdefType, env->mtrr_deftype);
             kvm_msr_entry_set(&msrs[n++],
@@ -1937,6 +1963,14 @@ static int kvm_get_msrs(X86CPU *cpu)
             msrs[n++].index = msr;
         }
     }
+    if (has_msr_hv_stimer) {
+        uint32_t msr;
+
+        for (msr = HV_X64_MSR_STIMER0_CONFIG; msr <= HV_X64_MSR_STIMER3_COUNT;
+             msr++) {
+            msrs[n++].index = msr;
+        }
+    }
     if (has_msr_mtrr) {
         msrs[n++].index = MSR_MTRRdefType;
         msrs[n++].index = MSR_MTRRfix64K_00000;
@@ -2108,6 +2142,20 @@ static int kvm_get_msrs(X86CPU *cpu)
         case HV_X64_MSR_SINT0 ... HV_X64_MSR_SINT15:
             env->msr_hv_synic_sint[index - HV_X64_MSR_SINT0] = msrs[i].data;
             break;
+        case HV_X64_MSR_STIMER0_CONFIG:
+        case HV_X64_MSR_STIMER1_CONFIG:
+        case HV_X64_MSR_STIMER2_CONFIG:
+        case HV_X64_MSR_STIMER3_CONFIG:
+            env->msr_hv_stimer_config[(index - HV_X64_MSR_STIMER0_CONFIG)/2] =
+                                msrs[i].data;
+            break;
+        case HV_X64_MSR_STIMER0_COUNT:
+        case HV_X64_MSR_STIMER1_COUNT:
+        case HV_X64_MSR_STIMER2_COUNT:
+        case HV_X64_MSR_STIMER3_COUNT:
+            env->msr_hv_stimer_count[(index - HV_X64_MSR_STIMER0_COUNT)/2] =
+                                msrs[i].data;
+            break;
         case MSR_MTRRdefType:
             env->mtrr_deftype = msrs[i].data;
             break;
diff --git a/target-i386/machine.c b/target-i386/machine.c
index d41e286ba4..6126d96d7f 100644
--- a/target-i386/machine.c
+++ b/target-i386/machine.c
@@ -746,6 +746,34 @@ static const VMStateDescription vmstate_msr_hyperv_synic = {
     }
 };
 
+static bool hyperv_stimer_enable_needed(void *opaque)
+{
+    X86CPU *cpu = opaque;
+    CPUX86State *env = &cpu->env;
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(env->msr_hv_stimer_config); i++) {
+        if (env->msr_hv_stimer_config[i] || env->msr_hv_stimer_count[i]) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static const VMStateDescription vmstate_msr_hyperv_stimer = {
+    .name = "cpu/msr_hyperv_stimer",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = hyperv_stimer_enable_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64_ARRAY(env.msr_hv_stimer_config,
+                             X86CPU, HV_SYNIC_STIMER_COUNT),
+        VMSTATE_UINT64_ARRAY(env.msr_hv_stimer_count,
+                             X86CPU, HV_SYNIC_STIMER_COUNT),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static bool avx512_needed(void *opaque)
 {
     X86CPU *cpu = opaque;
@@ -930,6 +958,7 @@ VMStateDescription vmstate_x86_cpu = {
         &vmstate_msr_hyperv_crash,
         &vmstate_msr_hyperv_runtime,
         &vmstate_msr_hyperv_synic,
+        &vmstate_msr_hyperv_stimer,
         &vmstate_avx512,
         &vmstate_xss,
         NULL