9:01 a.m.
From: Prerna Saxena <prerna(a)linux.vnet.ibm.com>
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 <prerna(a)linux.vnet.ibm.com>
---
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,
--
1.7.7
--
Prerna Saxena
Linux Technology Centre,
IBM Systems and Technology Lab,
Bangalore, India