Re: [libvirt] [RFC v3 PATCH 4/5] PowerPC : Clean up qemuBuildCommandLine to remove x86-specific assumptions from generic code.

From: Prerna Saxena&lt;prerna(a)linux.vnet.ibm.com&gt; Date: Mon, 21 Nov 2011 18:20:42 +0530 Subject: [PATCH 4/5] Clean up qemuBuildCommandLine to remove x86-specific assumptions from generic code. This implements the minimal set of changes needed in libvirt to launch a PowerPC-KVM based guest. It removes x86-specific assumptions about choice of serial driver backend from generic qemu guest commandline generation code. It also restricts the ACPI capability to be available for an x86 or x86_64 domain. This is not a complete solution -- it still does not guarantee libvirt the capability to flag non-supported options in guest XML. (Eg, an ACPI specification in a PowerPC guest XML will still get processed, even though qemu-system-ppc64 does not support it while qemu-system-x86_64 does.) This drawback exists because libvirt falls back on qemu to query supported features, and qemu '-h' blindly lists all capabilities -- irrespective of whether they are available while emulating a given architecture or not. The long-term solution would be for qemu to list out capabilities based on architecture and platform -- so that libvirt can cleanly make out what devices are supported on an arch (say 'ppc64') and platform (say, 'mac99'). Signed-off-by: Prerna Saxena&lt;prerna(a)linux.vnet.ibm.com&gt; --- src/qemu/qemu_command.c | 39 ++++++++++++++++++++++++++++++++++++--- src/qemu/qemu_command.h | 6 ++++++ 2 files changed, 42 insertions(+), 3 deletions(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 85b34bb..57b25d6 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4550,8 +4550,11 @@ qemuBuildCommandLine(virConnectPtr conn, VIR_FREE(devstr); virCommandAddArg(cmd, "-device"); - virCommandAddArgFormat(cmd, "isa-serial,chardev=char%s,id=%s", - serial->info.alias, serial->info.alias); + if (!(devstr = qemuBuildChrDeviceStr(serial, def->os.arch, + def->os.machine))) + goto error; + virCommandAddArg(cmd, devstr); + VIR_FREE(devstr); } else { virCommandAddArg(cmd, "-serial"); if (!(devstr = qemuBuildChrArgStr(&serial->source, NULL))) @@ -5438,6 +5441,34 @@ qemuBuildCommandLine(virConnectPtr conn, return NULL; } +/* This function generates the correct '-device' string for character + * devices of each architecture. + */ +char * +qemuBuildChrDeviceStr (virDomainChrDefPtr serial, + char *os_arch, + char *machine) +{ + virBuffer cmd = VIR_BUFFER_INITIALIZER; + + if (STREQ(os_arch, "ppc64")&& STREQ(machine, "pseries")) + virBufferAsprintf(&cmd, "spapr-vty,chardev=char%s", + serial->info.alias); + else + virBufferAsprintf(&cmd, "isa-serial,chardev=char%s,id=%s", + serial->info.alias, serial->info.alias); + + if (virBufferError(&cmd)) { + virReportOOMError(); + goto error; + } + + return virBufferContentAndReset(&cmd); + + error: + virBufferFreeAndReset(&cmd); + return NULL; +} /* * This method takes a string representing a QEMU command line ARGV set @@ -6649,7 +6680,9 @@ virDomainDefPtr qemuParseCommandLine(virCapsPtr caps, def->maxvcpus = 1; def->vcpus = 1; def->clock.offset = VIR_DOMAIN_CLOCK_OFFSET_UTC; - def->features = (1<< VIR_DOMAIN_FEATURE_ACPI) + + if (STREQ(def->os.arch, "i686")||STREQ(def->os.arch, "x86_64")) + def->features = (1<< VIR_DOMAIN_FEATURE_ACPI) /*| (1<< VIR_DOMAIN_FEATURE_APIC)*/; def->onReboot = VIR_DOMAIN_LIFECYCLE_RESTART; def->onCrash = VIR_DOMAIN_LIFECYCLE_DESTROY; diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h index dbe2fb2..1fe0394 100644 --- a/src/qemu/qemu_command.h +++ b/src/qemu/qemu_command.h @@ -53,6 +53,12 @@ virCommandPtr qemuBuildCommandLine(virConnectPtr conn, enum virNetDevVPortProfileOp vmop) ATTRIBUTE_NONNULL(1); +/* Generate string for arch-specific '-device' parameter */ +char * +qemuBuildChrDeviceStr (virDomainChrDefPtr serial, + char *os_arch, + char *machine);

+ /* With vlan == -1, use netdev syntax, else old hostnet */ char * qemuBuildHostNetStr(virDomainNetDefPtr net, char type_sep,