Add KVM paravirt cpuid leaf

Initialize KVM paravirt cpuid leaf and allow user to control guest
visible PV features through -cpu flag.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 27 insertions, 8 deletions

diff --git a/target-i386/helper.c b/target-i386/helper.c
index 049fccfc72..70762bb10a 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -58,10 +58,18 @@ static const char *ext3_feature_name[] = {
     NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 };
 
+static const char *kvm_feature_name[] = {
+    "kvmclock", "kvm_nopiodelay", "kvm_mmu", NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+};
+
 static void add_flagname_to_bitmaps(const char *flagname, uint32_t *features,
                                     uint32_t *ext_features,
                                     uint32_t *ext2_features,
-                                    uint32_t *ext3_features)
+                                    uint32_t *ext3_features,
+                                    uint32_t *kvm_features)
 {
     int i;
     int found = 0;
@@ -86,6 +94,12 @@ static void add_flagname_to_bitmaps(const char *flagname, uint32_t *features,
             *ext3_features |= 1 << i;
             found = 1;
         }
+    for ( i = 0 ; i < 32 ; i++ )
+        if (kvm_feature_name[i] && !strcmp (flagname, kvm_feature_name[i])) {
+            *kvm_features |= 1 << i;
+            found = 1;
+        }
+
     if (!found) {
         fprintf(stderr, "CPU feature %s not found\n", flagname);
     }
@@ -98,7 +112,7 @@ typedef struct x86_def_t {
     int family;
     int model;
     int stepping;
-    uint32_t features, ext_features, ext2_features, ext3_features;
+    uint32_t features, ext_features, ext2_features, ext3_features, kvm_features;
     uint32_t xlevel;
     char model_id[48];
     int vendor_override;
@@ -375,8 +389,8 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
 
     char *s = strdup(cpu_model);
     char *featurestr, *name = strtok(s, ",");
-    uint32_t plus_features = 0, plus_ext_features = 0, plus_ext2_features = 0, plus_ext3_features = 0;
-    uint32_t minus_features = 0, minus_ext_features = 0, minus_ext2_features = 0, minus_ext3_features = 0;
+    uint32_t plus_features = 0, plus_ext_features = 0, plus_ext2_features = 0, plus_ext3_features = 0, plus_kvm_features = 0;
+    uint32_t minus_features = 0, minus_ext_features = 0, minus_ext2_features = 0, minus_ext3_features = 0, minus_kvm_features = 0;
     uint32_t numvalue;
 
     def = NULL;
@@ -394,17 +408,20 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
         memcpy(x86_cpu_def, def, sizeof(*def));
     }
 
+    plus_kvm_features = ~0; /* not supported bits will be filtered out later */
+
     add_flagname_to_bitmaps("hypervisor", &plus_features,
-        &plus_ext_features, &plus_ext2_features, &plus_ext3_features);
+        &plus_ext_features, &plus_ext2_features, &plus_ext3_features,
+        &plus_kvm_features);
 
     featurestr = strtok(NULL, ",");
 
     while (featurestr) {
         char *val;
         if (featurestr[0] == '+') {
-            add_flagname_to_bitmaps(featurestr + 1, &plus_features, &plus_ext_features, &plus_ext2_features, &plus_ext3_features);
+            add_flagname_to_bitmaps(featurestr + 1, &plus_features, &plus_ext_features, &plus_ext2_features, &plus_ext3_features, &plus_kvm_features);
         } else if (featurestr[0] == '-') {
-            add_flagname_to_bitmaps(featurestr + 1, &minus_features, &minus_ext_features, &minus_ext2_features, &minus_ext3_features);
+            add_flagname_to_bitmaps(featurestr + 1, &minus_features, &minus_ext_features, &minus_ext2_features, &minus_ext3_features, &minus_kvm_features);
         } else if ((val = strchr(featurestr, '='))) {
             *val = 0; val++;
             if (!strcmp(featurestr, "family")) {
@@ -481,10 +498,12 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
     x86_cpu_def->ext_features |= plus_ext_features;
     x86_cpu_def->ext2_features |= plus_ext2_features;
     x86_cpu_def->ext3_features |= plus_ext3_features;
+    x86_cpu_def->kvm_features |= plus_kvm_features;
     x86_cpu_def->features &= ~minus_features;
     x86_cpu_def->ext_features &= ~minus_ext_features;
     x86_cpu_def->ext2_features &= ~minus_ext2_features;
     x86_cpu_def->ext3_features &= ~minus_ext3_features;
+    x86_cpu_def->kvm_features &= ~minus_kvm_features;
     free(s);
     return 0;
 
@@ -529,7 +548,7 @@ static int cpu_x86_register (CPUX86State *env, const char *cpu_model)
     env->cpuid_ext_features = def->ext_features;
     env->cpuid_ext2_features = def->ext2_features;
     env->cpuid_xlevel = def->xlevel;
-    env->cpuid_ext3_features = def->ext3_features;
+    env->cpuid_kvm_features = def->kvm_features;
     {
         const char *model_id = def->model_id;
         int c, len, i;