[libvirt] [PATCH 1/9] s390: Cpu driver support for update and compare

[Jason J. Herne]

Implement compare for s390. Required to test the guest against the host for
guest cpu model runnability checking. We always return IDENTICAL to bypass
Libvirt's checking. s390 will rely on Qemu to perform the runnability checking.

Implement update for s390. required to support use of cpu "host-model" mode.

Signed-off-by: Jason J. Herne <jjherne at linux.vnet.ibm.com>
Acked-by: Jiri Denemark <jdenemar at redhat.com>
---
 po/POTFILES.in     |  1 +
 src/cpu/cpu_s390.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 72 insertions(+), 2 deletions(-)

diff --git a/po/POTFILES.in b/po/POTFILES.in
index e66bb7a..59efd91 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -46,6 +46,7 @@ src/cpu/cpu.c
 src/cpu/cpu_arm.c
 src/cpu/cpu_map.c
 src/cpu/cpu_ppc64.c
+src/cpu/cpu_s390.c
 src/cpu/cpu_x86.c
 src/datatypes.c
 src/driver.c
diff --git a/src/cpu/cpu_s390.c b/src/cpu/cpu_s390.c
index 04a6bea..bdc9ab5 100644
--- a/src/cpu/cpu_s390.c
+++ b/src/cpu/cpu_s390.c
@@ -71,15 +71,84 @@ s390DataFree(virCPUDataPtr data)
     VIR_FREE(data);
 }
 
+static virCPUCompareResult
+virCPUs390Compare(virCPUDefPtr host ATTRIBUTE_UNUSED,
+                  virCPUDefPtr cpu ATTRIBUTE_UNUSED,
+                  bool failMessages ATTRIBUTE_UNUSED)
+{
+    /* s390 relies on Qemu to perform all runability checking. Return
+     * VIR_CPU_COMPARE_IDENTICAL to bypass Libvirt checking.
+     */
+    return VIR_CPU_COMPARE_IDENTICAL;
+}
+
+static int
+virCPUs390Update(virCPUDefPtr guest,
+                 const virCPUDef *host)
+{
+     virCPUDefPtr updated = NULL;
+     int ret = -1;
+     size_t i;
+
+     if (guest->match == VIR_CPU_MATCH_MINIMUM) {
+         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                        _("match mode %s not supported"),
+                        virCPUMatchTypeToString(guest->match));
+         goto cleanup;
+     }
+
+     if (guest->mode != VIR_CPU_MODE_HOST_MODEL) {
+         ret = 0;
+         goto cleanup;
+     }
+
+     if (!host) {
+         virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                        _("unknown host CPU model"));
+         goto cleanup;
+     }
+
+     if (!(updated = virCPUDefCopyWithoutModel(guest)))
+         goto cleanup;
+
+     updated->mode = VIR_CPU_MODE_CUSTOM;
+     if (virCPUDefCopyModel(updated, host, true) < 0)
+         goto cleanup;
+
+     for (i = 0; i < guest->nfeatures; i++) {
+         if (guest->features[i].policy == VIR_CPU_FEATURE_OPTIONAL) {
+             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                            _("only cpu feature policies 'require' and "
+                            "'disable' are supported for %s"),
+                            guest->features[i].name);
+             goto cleanup;
+        }
+
+        if (virCPUDefUpdateFeature(updated,
+                                   guest->features[i].name,
+                                   guest->features[i].policy) < 0)
+            goto cleanup;
+     }
+
+     virCPUDefStealModel(guest, updated, false);
+     guest->mode = VIR_CPU_MODE_CUSTOM;
+     guest->match = VIR_CPU_MATCH_EXACT;
+     ret = 0;
+
+ cleanup:
+     virCPUDefFree(updated);
+     return ret;
+}
+
 struct cpuArchDriver cpuDriverS390 = {
     .name = "s390",
     .arch = archs,
     .narch = ARRAY_CARDINALITY(archs),
-    .compare    = NULL,
+    .compare    = virCPUs390Compare,
     .decode     = s390Decode,
     .encode     = NULL,
     .free       = s390DataFree,
     .nodeData   = s390NodeData,
     .baseline   = NULL,
-    .update     = NULL,
+    .update     = virCPUs390Update,
 };
-- 
2.7.4