[libvirt] [PATCH v3 05/52] qemu: Copy CPU models in virQEMUCapsGetCPUDefinitions

[Jiri Denemark]

Rather than returning a direct pointer the list stored in qemuCaps the
function now creates a new copy of the CPU models list.

The main purpose of this seemingly useless change is to update callers
to free the result returned by virQEMUCapsGetCPUDefinitions because the
internals of this function will change significantly in the following
patches.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
Reviewed-by: Ján Tomko <jtomko at redhat.com>
---

Notes:
    Version 2:
    - no change
    
    Version 3:
    - g_autoptr

 src/conf/domain_capabilities.h |  2 ++
 src/qemu/qemu_capabilities.c   | 23 ++++++++++++++++++-----
 src/qemu/qemu_driver.c         |  2 +-
 src/qemu/qemu_process.c        |  7 +++++--
 tests/cputest.c                |  1 -
 5 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/src/conf/domain_capabilities.h b/src/conf/domain_capabilities.h
index 264c7fc429..36500435fd 100644
--- a/src/conf/domain_capabilities.h
+++ b/src/conf/domain_capabilities.h
@@ -139,6 +139,8 @@ struct _virDomainCapsCPUModels {
     virDomainCapsCPUModelPtr models;
 };
 
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(virDomainCapsCPUModels, virObjectUnref);
+
 typedef struct _virDomainCapsCPU virDomainCapsCPU;
 typedef virDomainCapsCPU *virDomainCapsCPUPtr;
 struct _virDomainCapsCPU {
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 8fd503a49c..afac77c1e4 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -1885,10 +1885,17 @@ virDomainCapsCPUModelsPtr
 virQEMUCapsGetCPUDefinitions(virQEMUCapsPtr qemuCaps,
                              virDomainVirtType type)
 {
+    virDomainCapsCPUModelsPtr cpuModels;
+
     if (type == VIR_DOMAIN_VIRT_KVM)
-        return qemuCaps->kvmCPUModels;
+        cpuModels = qemuCaps->kvmCPUModels;
     else
-        return qemuCaps->tcgCPUModels;
+        cpuModels = qemuCaps->tcgCPUModels;
+
+    if (!cpuModels)
+        return NULL;
+
+    return virDomainCapsCPUModelsCopy(cpuModels);
 }
 
 
@@ -3112,6 +3119,7 @@ virQEMUCapsInitCPUModelX86(virQEMUCapsPtr qemuCaps,
                            virCPUDefPtr cpu,
                            bool migratable)
 {
+    g_autoptr(virDomainCapsCPUModels) cpuModels = NULL;
     virCPUDataPtr data = NULL;
     int ret = -1;
 
@@ -3121,7 +3129,9 @@ virQEMUCapsInitCPUModelX86(virQEMUCapsPtr qemuCaps,
     if (!(data = virQEMUCapsGetCPUModelX86Data(qemuCaps, model, migratable)))
         goto cleanup;
 
-    if (cpuDecode(cpu, data, virQEMUCapsGetCPUDefinitions(qemuCaps, type)) < 0)
+    cpuModels = virQEMUCapsGetCPUDefinitions(qemuCaps, type);
+
+    if (cpuDecode(cpu, data, cpuModels) < 0)
         goto cleanup;
 
     ret = 0;
@@ -3204,10 +3214,13 @@ virQEMUCapsInitHostCPUModel(virQEMUCapsPtr qemuCaps,
     if ((rc = virQEMUCapsInitCPUModel(qemuCaps, type, cpu, false)) < 0) {
         goto error;
     } else if (rc == 1) {
+        g_autoptr(virDomainCapsCPUModels) cpuModels = NULL;
+
         VIR_DEBUG("No host CPU model info from QEMU; probing host CPU directly");
 
-        hostCPU = virQEMUCapsProbeHostCPU(hostArch,
-                                          virQEMUCapsGetCPUDefinitions(qemuCaps, type));
+        cpuModels = virQEMUCapsGetCPUDefinitions(qemuCaps, type);
+        hostCPU = virQEMUCapsProbeHostCPU(hostArch, cpuModels);
+
         if (!hostCPU ||
             virCPUDefCopyModelFilter(cpu, hostCPU, true,
                                      virQEMUCapsCPUFilterFeatures,
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index d17c18705b..380943dda3 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -13704,7 +13704,7 @@ qemuConnectBaselineHypervisorCPU(virConnectPtr conn,
     g_autoptr(virQEMUCaps) qemuCaps = NULL;
     virArch arch;
     virDomainVirtType virttype;
-    virDomainCapsCPUModelsPtr cpuModels;
+    g_autoptr(virDomainCapsCPUModels) cpuModels = NULL;
     bool migratable;
     virCPUDefPtr cpu = NULL;
     char *cpustr = NULL;
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index ed8666e9d1..5bc13035a4 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -6110,6 +6110,8 @@ qemuProcessUpdateGuestCPU(virDomainDefPtr def,
 
     /* nothing to update for host-passthrough */
     if (def->cpu->mode != VIR_CPU_MODE_HOST_PASSTHROUGH) {
+        g_autoptr(virDomainCapsCPUModels) cpuModels = NULL;
+
         if (def->cpu->check == VIR_CPU_CHECK_PARTIAL &&
             virCPUCompare(caps->host.arch,
                           virQEMUCapsGetHostModel(qemuCaps, def->virtType,
@@ -6122,8 +6124,9 @@ qemuProcessUpdateGuestCPU(virDomainDefPtr def,
                                                  VIR_QEMU_CAPS_HOST_CPU_MIGRATABLE)) < 0)
             return -1;
 
-        if (virCPUTranslate(def->os.arch, def->cpu,
-                            virQEMUCapsGetCPUDefinitions(qemuCaps, def->virtType)) < 0)
+        cpuModels = virQEMUCapsGetCPUDefinitions(qemuCaps, def->virtType);
+
+        if (virCPUTranslate(def->os.arch, def->cpu, cpuModels) < 0)
             return -1;
 
         def->cpu->fallback = VIR_CPU_FALLBACK_FORBID;
diff --git a/tests/cputest.c b/tests/cputest.c
index 6ead9e0982..e75e8bf906 100644
--- a/tests/cputest.c
+++ b/tests/cputest.c
@@ -549,7 +549,6 @@ cpuTestGetCPUModels(const struct data *data,
         return -1;
 
     *models = virQEMUCapsGetCPUDefinitions(qemuCaps, VIR_DOMAIN_VIRT_KVM);
-    virObjectRef(*models);
 
     virObjectUnref(qemuCaps);
 
-- 
2.23.0