[libvirt] [PATCH v2 41/45] cpu: Introduce virCPUCheckFeature

[Jiri Denemark]

The function is similar to virCPUDataCheckFeature, but it works directly
on CPU definition rather than requiring it to be transformed into CPU
data first.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---

Notes:
    Version 2:
    - new patch (separated from 38/41)

 src/cpu/cpu.c            | 36 ++++++++++++++++++++++++++++++++++++
 src/cpu/cpu.h            | 13 +++++++++++++
 src/cpu/cpu_x86.c        | 23 +++++++++++++++++++++++
 src/libvirt_private.syms |  1 +
 tests/cputest.c          |  6 +++++-
 5 files changed, 78 insertions(+), 1 deletion(-)

diff --git a/src/cpu/cpu.c b/src/cpu/cpu.c
index cc7d03c..2ab61d7 100644
--- a/src/cpu/cpu.c
+++ b/src/cpu/cpu.c
@@ -648,6 +648,42 @@ virCPUUpdate(virArch arch,
 
 
 /**
+ * virCPUCheckFeature:
+ *
+ * @arch: CPU architecture
+ * @cpu: CPU definition
+ * @feature: feature to be checked for
+ *
+ * Checks whether @feature is supported by the CPU described by @cpu.
+ *
+ * Returns 1 if the feature is supported, 0 if it's not supported, or
+ * -1 on error.
+ */
+int
+virCPUCheckFeature(virArch arch,
+                   const virCPUDef *cpu,
+                   const char *feature)
+{
+    struct cpuArchDriver *driver;
+
+    VIR_DEBUG("arch=%s, cpu=%p, feature=%s",
+              virArchToString(arch), cpu, feature);
+
+    if (!(driver = cpuGetSubDriver(arch)))
+        return -1;
+
+    if (!driver->checkFeature) {
+        virReportError(VIR_ERR_NO_SUPPORT,
+                       _("cannot check guest CPU feature for %s architecture"),
+                       virArchToString(arch));
+        return -1;
+    }
+
+    return driver->checkFeature(cpu, feature);
+}
+
+
+/**
  * virCPUDataCheckFeature:
  *
  * @data: CPU data
diff --git a/src/cpu/cpu.h b/src/cpu/cpu.h
index 71fa2da..f14c2c8 100644
--- a/src/cpu/cpu.h
+++ b/src/cpu/cpu.h
@@ -91,6 +91,10 @@ typedef int
                     const virCPUDef *host);
 
 typedef int
+(*virCPUArchCheckFeature)(const virCPUDef *cpu,
+                          const char *feature);
+
+typedef int
 (*virCPUArchDataCheckFeature)(const virCPUData *data,
                               const char *feature);
 
@@ -120,6 +124,7 @@ struct cpuArchDriver {
     cpuArchGuestData    guestData;
     cpuArchBaseline     baseline;
     virCPUArchUpdate    update;
+    virCPUArchCheckFeature checkFeature;
     virCPUArchDataCheckFeature dataCheckFeature;
     cpuArchDataFormat   dataFormat;
     cpuArchDataParse    dataParse;
@@ -193,6 +198,14 @@ virCPUUpdate(virArch arch,
              const virCPUDef *host)
     ATTRIBUTE_NONNULL(2);
 
+
+int
+virCPUCheckFeature(virArch arch,
+                   const virCPUDef *cpu,
+                   const char *feature)
+    ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3);
+
+
 int
 virCPUDataCheckFeature(const virCPUData *data,
                        const char *feature)
diff --git a/src/cpu/cpu_x86.c b/src/cpu/cpu_x86.c
index ae552ac..7224d76 100644
--- a/src/cpu/cpu_x86.c
+++ b/src/cpu/cpu_x86.c
@@ -2602,6 +2602,28 @@ virCPUx86Update(virCPUDefPtr guest,
 
 
 static int
+virCPUx86CheckFeature(const virCPUDef *cpu,
+                      const char *name)
+{
+    int ret = -1;
+    virCPUx86MapPtr map;
+    virCPUx86ModelPtr model = NULL;
+
+    if (!(map = virCPUx86GetMap()))
+        return -1;
+
+    if (!(model = x86ModelFromCPU(cpu, map, -1)))
+        goto cleanup;
+
+    ret = x86FeatureInData(name, &model->data, map);
+
+ cleanup:
+    x86ModelFree(model);
+    return ret;
+}
+
+
+static int
 virCPUx86DataCheckFeature(const virCPUData *data,
                           const char *name)
 {
@@ -2709,6 +2731,7 @@ struct cpuArchDriver cpuDriverX86 = {
     .guestData  = x86GuestData,
     .baseline   = x86Baseline,
     .update     = virCPUx86Update,
+    .checkFeature = virCPUx86CheckFeature,
     .dataCheckFeature = virCPUx86DataCheckFeature,
     .dataFormat = x86CPUDataFormat,
     .dataParse  = x86CPUDataParse,
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 8575f55..c4fd7ae 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -974,6 +974,7 @@ cpuEncode;
 cpuGetModels;
 cpuGuestData;
 cpuNodeData;
+virCPUCheckFeature;
 virCPUDataCheckFeature;
 virCPUTranslate;
 virCPUUpdate;
diff --git a/tests/cputest.c b/tests/cputest.c
index ce8f8c0..72f00b6 100644
--- a/tests/cputest.c
+++ b/tests/cputest.c
@@ -430,7 +430,11 @@ cpuTestHasFeature(const void *arg)
                   NULL, NULL, NULL, NULL) < 0)
         goto cleanup;
 
-    result = virCPUDataCheckFeature(hostData, data->name);
+    result = virCPUCheckFeature(host->arch, host, data->name);
+
+    if (data->result == result)
+        result = virCPUDataCheckFeature(hostData, data->name);
+
     if (data->result == -1)
         virResetLastError();
 
-- 
2.10.0