Re: [libvirt] [PATCH 4/6] Canonicalize qemu machine types

On Mon, 2009-07-27 at 15:42 +0200, Daniel Veillard wrote: > On Thu, Jul 23, 2009 at 06:34:42PM +0100, Mark McLoughlin wrote: > > In qemu-0.11 there is a 'pc-0.10' machine type which allows you to run > > guests with a machine which is compatible with the pc machine in > > qemu-0.10 - e.g. using the original PCI class for virtio-blk and > > virtio-console and disabling MSI support in virtio-net. The idea here > > is that we don't want to suprise guests by changing the hardware when > > qemu is updated. > > > > I've just posted some patches for qemu-0.11 which allows libvirt to > > canonicalize the 'pc' machine alias to the latest machine version. > > > > This patches makes us use that so that when a guest is configured to > > use the 'pc' machine type, we resolve that to 'pc-0.11' machine and > > save that in the guest XML. > > > > See also: > > > > https://fedoraproject.org/wiki/Features/KVM_Stable_Guest_ABI > > > > * src/qemu_conf.c: add qemudCanonicalizeMachine() to canonicalize > > the machine type according to the machine aliases in capabilities > > > [...] > > /* Format is: > > - * <machine> <desc> [(default)] > > + * <machine> <desc> [(default)|(alias of <canonical>)] > > */ > > static int > > qemudParseMachineTypesStr(const char *output, > > @@ -319,6 +319,15 @@ qemudParseMachineTypesStr(const char *output, > > list[0] = machine; > > nitems++; > > } > > + > > + if ((t = strstr(p, "(alias of ")) && (!next || t < next)) { > > + p = t + strlen("(alias of "); > > + if (!(t = strchr(p, ')')) || (next && t >= next)) > > + continue; > > + > > + if (!(machine->canonical = strndup(p, t - p))) > > + goto error; > > + } > > } while ((p = next)); > > hum, if you get (alias of foo ) your canonical will end up being > " foo " instead of "foo" maybe spaces should be stripped before and > after the name (i.e. it would have been perfect in an XML attribute but > well ...) If only we had something like g_strstrip() :-)

> [...] > > +static int > > +qemudCanonicalizeMachineFromInfo(virDomainDefPtr def, > > + virCapsGuestDomainInfoPtr info, > > + char **canonical) > > +{ > > + int i; > > + > > + *canonical = NULL; > > + > > + for (i = 0; i < info->nmachines; i++) { > > + virCapsGuestMachinePtr machine = info->machines[i]; > > + > > + if (!machine->canonical) > > + continue; > > + > > + if (strcmp(def->os.machine, machine->name) != 0) > > + continue; > > + > > + if (!(*canonical = strdup(machine->canonical))) > > virReportOOMError(NULL) please :-) Yep, thanks.