[libvirt] [PATCH 2/2] Add QEMU support for virtio channel

[Daniel P. Berrange]

On Wed, Feb 17, 2010 at 05:11:01PM +0000, Matthew Booth wrote:
> Support virtio-serial controller and virtio channel in QEMU backend. Will output
> the following for virtio-serial controller:
> 
> -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x4,max_ports=16,vectors=4
> 
> and the following for a virtio channel:
> 
> -chardev pty,id=channel0 \
> -device virtserialport,bus=virtio-serial0.0,chardev=channel0,name=org.linux-kvm.port.0
> 
> * src/qemu/qemu_conf.c: Add argument output for virtio
> * tests/qemuxml2argvtest.c
>   tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
>                       : Add test for QEMU command line generation
> ---
>  src/qemu/qemu_conf.c                               |   91 +++++++++++++++++++-
>  .../qemuxml2argv-channel-virtio.args               |    1 +
>  tests/qemuxml2argvtest.c                           |    1 +
>  3 files changed, 92 insertions(+), 1 deletions(-)
>  create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
> 
> diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
> index 456ee34..110409d 100644
> --- a/src/qemu/qemu_conf.c
> +++ b/src/qemu/qemu_conf.c
> @@ -2168,7 +2168,6 @@ qemuAssignDevicePCISlots(virDomainDefPtr def, qemuDomainPCIAddressSetPtr addrs)
>      }
>      for (i = 0; i < def->nchannels ; i++) {
>          /* Nada - none are PCI based (yet) */
> -        /* XXX virtio-serial will need one */
>      }
>      if (def->watchdog &&
>          def->watchdog->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) {
> @@ -2465,6 +2464,23 @@ qemuBuildControllerDevStr(virDomainControllerDefPtr def)
>          virBufferVSprintf(&buf, ",id=scsi%d", def->idx);
>          break;
>  
> +    case VIR_DOMAIN_CONTROLLER_TYPE_VIRTIO_SERIAL:
> +        if (def->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI) {
> +            virBufferAddLit(&buf, "virtio-serial-pci");
> +        } else {
> +            virBufferAddLit(&buf, "virtio-serial");
> +        }
> +        virBufferVSprintf(&buf, ",id=virtio-serial%d", def->idx);
> +        if (def->opts.vioserial.max_ports != -1) {
> +            virBufferVSprintf(&buf, ",max_ports=%d",
> +                              def->opts.vioserial.max_ports);
> +        }
> +        if (def->opts.vioserial.vectors != -1) {
> +            virBufferVSprintf(&buf, ",vectors=%d",
> +                              def->opts.vioserial.vectors);
> +        }
> +        break;
> +
>      /* We always get an IDE controller, whether we want it or not. */
>      case VIR_DOMAIN_CONTROLLER_TYPE_IDE:
>      default:
> @@ -3830,6 +3846,79 @@ int qemudBuildCommandLine(virConnectPtr conn,
>              }
>              VIR_FREE(addr);
>              ADD_ARG(devstr);
> +            break;
> +
> +        case VIR_DOMAIN_CHR_TARGET_TYPE_VIRTIO:
> +            if (!(qemuCmdFlags & QEMUD_CMD_FLAG_DEVICE)) {
> +                qemuReportError(VIR_ERR_NO_SUPPORT, "%s",
> +                    _("virtio channel requires QEMU to support -device"));
> +                goto error;
> +            }
> +
> +            ADD_ARG_LIT("-chardev");
> +            if (!(devstr = qemuBuildChrChardevStr(channel)))
> +                goto error;
> +            ADD_ARG(devstr);

It would be desirable to put the stuff that follows this point, into
a  qemuBuildVirtioSerialPortDevStr()  method, because the main 
qemudBuildCommandLine() method is far too large & unwieldly these days.

> +
> +            virBuffer virtiodev = VIR_BUFFER_INITIALIZER;
> +            virBufferAddLit(&virtiodev, "virtserialport");
> +
> +            if (channel->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) {
> +                /* Check it's a virtio-serial address */
> +                if (channel->info.type !=
> +                    VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_SERIAL)
> +                {
> +                    qemuReportError(VIR_ERR_INTERNAL_ERROR,
> +                                    _("virtio serial device has invalid "
> +                                      "address type"));
> +                    virBufferFreeAndReset(&virtiodev);
> +                    goto error;
> +                }
> +
> +                /* Look for the virtio-serial controller */
> +                const char *vsalias = NULL;
> +                int vs = 0;
> +                int c;
> +                for (c = 0; c < def->ncontrollers; c++) {
> +                    if (def->controllers[c]->type !=
> +                        VIR_DOMAIN_CONTROLLER_TYPE_VIRTIO_SERIAL)
> +                    {
> +                        continue;
> +                    }
> +
> +                    if (vs == channel->info.addr.vioserial.controller) {
> +                        vsalias = def->controllers[c]->info.alias;
> +                        break;
> +                    }
> +
> +                    vs++;
> +                }
> +
> +                if (!vsalias) {
> +                    qemuReportError(VIR_ERR_INTERNAL_ERROR,
> +                                    _("virtio serial device address controller "
> +                                      "does not exist"));
> +                    virBufferFreeAndReset(&virtiodev);
> +                    goto error;
> +                }

We don't really need this loop / check there, since the XML parser routine
has already guarenteed that we have a controller associated with the port.
Just 

> +
> +                virBufferVSprintf(&virtiodev, ",bus=%s.%d",
> +                                  vsalias, channel->info.addr.vioserial.bus);

This can just be

               virBufferVSprintf(&virtiodev, ",bus=virtio-serial%d.%d",
                                 channel->info.addr.vioserial.controller,
                                 channel->info.addr.vioserial.bus);



> +            }
> +
> +            virBufferVSprintf(&virtiodev, ",chardev=%s", channel->info.alias);
> +            if (channel->target.name) {
> +                virBufferVSprintf(&virtiodev, ",name=%s", channel->target.name);
> +            }
> +            if (virBufferError(&virtiodev)) {
> +                virReportOOMError();
> +                goto error;
> +            }
> +
> +            ADD_ARG_LIT("-device");
> +            ADD_ARG(virBufferContentAndReset(&virtiodev));
> +
> +            break;
>          }
>      }
>  


Regards,
Daniel
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