[PULL 11/24] i386: stop using env->features[] for filling Hyper-V CPUIDs

[Eduardo Habkost <ehabkost@redhat.com>]

From: Vitaly Kuznetsov <vkuznets@redhat.com>

As a preparatory patch to dropping Hyper-V CPUID leaves from
feature_word_info[] stop using env->features[] as a temporary
storage of Hyper-V CPUIDs, just build Hyper-V CPUID leaves directly
from kvm_hyperv_properties[] data.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20210422161130.652779-5-vkuznets@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target/i386/cpu.h     |  1 +
 target/i386/kvm/kvm.c | 80 +++++++++++++++++++++++--------------------
 2 files changed, 43 insertions(+), 38 deletions(-)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index da72aa52286..681f11607ff 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1699,6 +1699,7 @@ struct X86CPU {
     uint32_t hyperv_interface_id[4];
     uint32_t hyperv_version_id[4];
     uint32_t hyperv_limits[3];
+    uint32_t hyperv_nested[4];
 
     bool check_cpuid;
     bool enforce_cpuid;
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 4cd4df223fc..346528c6496 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -1112,7 +1112,6 @@ static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid,
                                   int feature)
 {
     X86CPU *cpu = X86_CPU(cs);
-    CPUX86State *env = &cpu->env;
     uint32_t r, fw, bits;
     uint64_t deps;
     int i, dep_feat;
@@ -1152,8 +1151,6 @@ static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid,
                 return 0;
             }
         }
-
-        env->features[fw] |= bits;
     }
 
     if (cpu->hyperv_passthrough) {
@@ -1163,6 +1160,29 @@ static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid,
     return 0;
 }
 
+static uint32_t hv_build_cpuid_leaf(CPUState *cs, uint32_t fw)
+{
+    X86CPU *cpu = X86_CPU(cs);
+    uint32_t r = 0;
+    int i, j;
+
+    for (i = 0; i < ARRAY_SIZE(kvm_hyperv_properties); i++) {
+        if (!hyperv_feat_enabled(cpu, i)) {
+            continue;
+        }
+
+        for (j = 0; j < ARRAY_SIZE(kvm_hyperv_properties[i].flags); j++) {
+            if (kvm_hyperv_properties[i].flags[j].fw != fw) {
+                continue;
+            }
+
+            r |= kvm_hyperv_properties[i].flags[j].bits;
+        }
+    }
+
+    return r;
+}
+
 /*
  * Fill in Hyper-V CPUIDs. Returns the number of entries filled in cpuid_ent in
  * case of success, errno < 0 in case of failure and 0 when no Hyper-V
@@ -1172,9 +1192,8 @@ static int hyperv_handle_properties(CPUState *cs,
                                     struct kvm_cpuid_entry2 *cpuid_ent)
 {
     X86CPU *cpu = X86_CPU(cs);
-    CPUX86State *env = &cpu->env;
     struct kvm_cpuid2 *cpuid;
-    struct kvm_cpuid_entry2 *c;
+    struct kvm_cpuid_entry2 *c, *c2;
     uint32_t cpuid_i = 0;
     int r;
 
@@ -1195,9 +1214,7 @@ static int hyperv_handle_properties(CPUState *cs,
         }
 
         if (!r) {
-            env->features[FEAT_HV_RECOMM_EAX] |=
-                HV_ENLIGHTENED_VMCS_RECOMMENDED;
-            env->features[FEAT_HV_NESTED_EAX] = evmcs_version;
+            cpu->hyperv_nested[0] = evmcs_version;
         }
     }
 
@@ -1236,13 +1253,6 @@ static int hyperv_handle_properties(CPUState *cs,
             cpu->hyperv_version_id[3] = c->edx;
         }
 
-        c = cpuid_find_entry(cpuid, HV_CPUID_FEATURES, 0);
-        if (c) {
-            env->features[FEAT_HYPERV_EAX] = c->eax;
-            env->features[FEAT_HYPERV_EBX] = c->ebx;
-            env->features[FEAT_HYPERV_EDX] = c->edx;
-        }
-
         c = cpuid_find_entry(cpuid, HV_CPUID_IMPLEMENT_LIMITS, 0);
         if (c) {
             cpu->hv_max_vps = c->eax;
@@ -1253,23 +1263,8 @@ static int hyperv_handle_properties(CPUState *cs,
 
         c = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0);
         if (c) {
-            env->features[FEAT_HV_RECOMM_EAX] = c->eax;
             cpu->hyperv_spinlock_attempts = c->ebx;
         }
-        c = cpuid_find_entry(cpuid, HV_CPUID_NESTED_FEATURES, 0);
-        if (c) {
-            env->features[FEAT_HV_NESTED_EAX] = c->eax;
-        }
-    }
-
-    if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_ON) {
-        env->features[FEAT_HV_RECOMM_EAX] |= HV_NO_NONARCH_CORESHARING;
-    } else if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_AUTO) {
-        c = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0);
-        if (c) {
-            env->features[FEAT_HV_RECOMM_EAX] |=
-                c->eax & HV_NO_NONARCH_CORESHARING;
-        }
     }
 
     /* Features */
@@ -1299,9 +1294,6 @@ static int hyperv_handle_properties(CPUState *cs,
         r |= 1;
     }
 
-    /* Not exposed by KVM but needed to make CPU hotplug in Windows work */
-    env->features[FEAT_HYPERV_EDX] |= HV_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
-
     if (r) {
         r = -ENOSYS;
         goto free;
@@ -1331,15 +1323,27 @@ static int hyperv_handle_properties(CPUState *cs,
 
     c = &cpuid_ent[cpuid_i++];
     c->function = HV_CPUID_FEATURES;
-    c->eax = env->features[FEAT_HYPERV_EAX];
-    c->ebx = env->features[FEAT_HYPERV_EBX];
-    c->edx = env->features[FEAT_HYPERV_EDX];
+    c->eax = hv_build_cpuid_leaf(cs, FEAT_HYPERV_EAX);
+    c->ebx = hv_build_cpuid_leaf(cs, FEAT_HYPERV_EBX);
+    c->edx = hv_build_cpuid_leaf(cs, FEAT_HYPERV_EDX);
+
+    /* Not exposed by KVM but needed to make CPU hotplug in Windows work */
+    c->edx |= HV_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
 
     c = &cpuid_ent[cpuid_i++];
     c->function = HV_CPUID_ENLIGHTMENT_INFO;
-    c->eax = env->features[FEAT_HV_RECOMM_EAX];
+    c->eax = hv_build_cpuid_leaf(cs, FEAT_HV_RECOMM_EAX);
     c->ebx = cpu->hyperv_spinlock_attempts;
 
+    if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_ON) {
+        c->eax |= HV_NO_NONARCH_CORESHARING;
+    } else if (cpu->hyperv_no_nonarch_cs == ON_OFF_AUTO_AUTO) {
+        c2 = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0);
+        if (c2) {
+            c->eax |= c2->eax & HV_NO_NONARCH_CORESHARING;
+        }
+    }
+
     c = &cpuid_ent[cpuid_i++];
     c->function = HV_CPUID_IMPLEMENT_LIMITS;
     c->eax = cpu->hv_max_vps;
@@ -1359,7 +1363,7 @@ static int hyperv_handle_properties(CPUState *cs,
 
         c = &cpuid_ent[cpuid_i++];
         c->function = HV_CPUID_NESTED_FEATURES;
-        c->eax = env->features[FEAT_HV_NESTED_EAX];
+        c->eax = cpu->hyperv_nested[0];
     }
     r = cpuid_i;
 
-- 
2.30.2