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

[Matthew Booth]

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);
+
+            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;
+                }
+
+                virBufferVSprintf(&virtiodev, ",bus=%s.%d",
+                                  vsalias, 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;
         }
     }
 
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args b/tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
new file mode 100644
index 0000000..4097065
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args
@@ -0,0 +1 @@
+LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test /usr/bin/qemu -S -M pc -m 214 -smp 1 -nographic -nodefaults -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -device virtio-serial-pci,id=virtio-serial0,max_ports=16,vectors=4,bus=pci.0,addr=0x4 -device virtio-serial-pci,id=virtio-serial1,bus=pci.0,addr=0xa -hda /dev/HostVG/QEMUGuest1 -chardev pty,id=channel0 -device virtserialport,chardev=channel0,name=org.linux-kvm.port.0 -chardev pty,id=channel1 -device virtserialport,bus=virtio-serial1.0,chardev=channel1,name=org.linux-kvm.port.1 -usb -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index aa42f99..a8c9ed3 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -318,6 +318,7 @@ mymain(int argc, char **argv)
     DO_TEST("console-compat-chardev", QEMUD_CMD_FLAG_CHARDEV|QEMUD_CMD_FLAG_DEVICE);
 
     DO_TEST("channel-guestfwd", QEMUD_CMD_FLAG_CHARDEV|QEMUD_CMD_FLAG_DEVICE);
+    DO_TEST("channel-virtio", QEMUD_CMD_FLAG_DEVICE);
 
     DO_TEST("watchdog", 0);
     DO_TEST("watchdog-device", QEMUD_CMD_FLAG_DEVICE);
-- 
1.6.6