[libvirt] [PATCHv2 1/2] Optimize machine option to set more options with it.

[Li Zhang]

From: Li Zhang <zhlcindy at linux.vnet.ibm.com>

 Currently, -machine option is used only when dump-guest-core is set.

 To use options defined in machine option for newer version of QEMU,
 it needs to use -machine xxx, and to be compatible with older version
 -M, this patch addes QEMU_CAPS_MACHINE_OPT capability for newer version,
 say 1.2.0.

Signed-off-by: Li Zhang <zhlcindy at linux.vnet.ibm.com>
---
 v2 -> v1:
  * Split the patch to 2 parts suggested by Daniel P.Berrange
  * Rename QEMU_CAPS_MACH_OPT to QEMU_CAPS_MACHINE_OPT
  * Remove version 1.1 assertion for QEMU_CAPS_MACHINE_OPT   

 src/qemu/qemu_capabilities.c |    6 +++++-
 src/qemu/qemu_capabilities.h |    1 +
 src/qemu/qemu_command.c      |   30 +++++++++++++++++++-----------
 tests/qemuxml2argvtest.c     |    6 +++---
 4 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 519d2c5..778e825 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -210,7 +210,8 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
 
               "rng-random", /* 130 */
               "rng-egd",
-              "virtio-ccw"
+              "virtio-ccw",
+              "machine-opt"
     );
 
 struct _virQEMUCaps {
@@ -2442,6 +2443,9 @@ virQEMUCapsInitQMP(virQEMUCapsPtr qemuCaps,
 
     virQEMUCapsInitQMPBasic(qemuCaps);
 
+    /* machine option is supported for newer version */
+    virQEMUCapsSet(qemuCaps, QEMU_CAPS_MACHINE_OPT);
+
     if (!(archstr = qemuMonitorGetTargetArch(mon)))
         goto cleanup;
 
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index da06e27..66df556 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -172,6 +172,7 @@ enum virQEMUCapsFlags {
                                            virtio rng */
     QEMU_CAPS_OBJECT_RNG_EGD     = 131, /* EGD protocol daemon for rng */
     QEMU_CAPS_VIRTIO_CCW         = 132, /* -device virtio-*-ccw */
+    QEMU_CAPS_MACHINE_OPT        = 133, /* -machine xxxx*/
 
     QEMU_CAPS_LAST,                   /* this must always be the last item */
 };
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index dc49d44..c39faf0 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -4941,6 +4941,8 @@ qemuBuildMachineArgStr(virCommandPtr cmd,
                        const virDomainDefPtr def,
                        virQEMUCapsPtr qemuCaps)
 {
+    virBuffer buf = VIR_BUFFER_INITIALIZER;
+
     /* This should *never* be NULL, since we always provide
      * a machine in the capabilities data for QEMU. So this
      * check is just here as a safety in case the unexpected
@@ -4948,27 +4950,33 @@ qemuBuildMachineArgStr(virCommandPtr cmd,
     if (!def->os.machine)
         return 0;
 
-    if (!def->mem.dump_core) {
+    if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_MACHINE_OPT)) {
         /* if no parameter to the machine type is needed, we still use
          * '-M' to keep the most of the compatibility with older versions.
          */
         virCommandAddArgList(cmd, "-M", def->os.machine, NULL);
     } else {
-        if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DUMP_GUEST_CORE)) {
-            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-                           "%s", _("dump-guest-core is not available "
-                                   " with this QEMU binary"));
-            return -1;
-        }
 
         /* However, in case there is a parameter to be added, we need to
          * use the "-machine" parameter because qemu is not parsing the
          * "-M" correctly */
+
         virCommandAddArg(cmd, "-machine");
-        virCommandAddArgFormat(cmd,
-                               "%s,dump-guest-core=%s",
-                               def->os.machine,
-                               virDomainMemDumpTypeToString(def->mem.dump_core));
+        virBufferAsprintf(&buf, "%s", def->os.machine);
+
+        if (def->mem.dump_core) {
+            if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DUMP_GUEST_CORE)) {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                               "%s", _("dump-guest-core is not available "
+                                " with this QEMU binary"));
+                return -1;
+            }
+
+            virBufferAsprintf(&buf, ",dump-guest-core=%s",
+                              virDomainMemDumpTypeToString(def->mem.dump_core));
+        }
+
+        virCommandAddArg(cmd, virBufferContentAndReset(&buf));
     }
 
     return 0;
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index c77b73f..352b41f 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -363,9 +363,9 @@ mymain(void)
     DO_TEST("minimal-s390", QEMU_CAPS_NAME);
     DO_TEST("machine-aliases1", NONE);
     DO_TEST("machine-aliases2", QEMU_CAPS_KVM);
-    DO_TEST("machine-core-on", QEMU_CAPS_DUMP_GUEST_CORE);
-    DO_TEST("machine-core-off", QEMU_CAPS_DUMP_GUEST_CORE);
-    DO_TEST_FAILURE("machine-core-on", NONE);
+    DO_TEST("machine-core-on", QEMU_CAPS_MACHINE_OPT, QEMU_CAPS_DUMP_GUEST_CORE);
+    DO_TEST("machine-core-off", QEMU_CAPS_MACHINE_OPT, QEMU_CAPS_DUMP_GUEST_CORE);
+    DO_TEST_FAILURE("machine-core-on", QEMU_CAPS_MACHINE_OPT, NONE);
     DO_TEST("boot-cdrom", NONE);
     DO_TEST("boot-network", NONE);
     DO_TEST("boot-floppy", NONE);
-- 
1.7.10.1