conf: Add channel state for virtio channels to the XML

To track state of virtio channels this patch adds a new output-only
attribute called 'state' to the <target> element of virtio channels.

This will be later populated with the guest state of the channel.

docs/formatdomain.html.in

@@ -4911,7 +4911,7 @@ qemu-kvm -net nic,model=? /dev/null
     </channel>
     <channel type='unix'>
       <source mode='bind' path='/var/lib/libvirt/qemu/f16x86_64.agent'/>
-      <target type='virtio' name='org.qemu.guest_agent.0'/>
+      <target type='virtio' name='org.qemu.guest_agent.0' state='connected'/>
     </channel>
     <channel type='spicevmc'>
       <target type='virtio' name='com.redhat.spice.0'/>
@@ -4950,7 +4950,12 @@ qemu-kvm -net nic,model=? /dev/null
         This is very useful in case of a qemu guest agent, where users don't
         usually care about the source path since it's libvirt who talks to
         the guest agent. In case users want to utilize this feature, they should
-        leave <code>&lt;source&gt;</code> element out.
+        leave <code>&lt;source&gt;</code> element out. <span class="since">Since
+        1.2.11</span> the active XML for a virtio channel may contain an optional
+        <code>state</code> attribute that reflects whether a process in the
+        guest is active on the channel. This is an output-only attribute.
+        Possible values for the <code>state</code> attribute are
+        <code>connected</code> and <code>disconnected</code>.
       </dd>
       <dt><code>spicevmc</code></dt>
       <dd>Paravirtualized SPICE channel. The domain must also have a

docs/schemas/domaincommon.rng

@@ -3377,6 +3377,14 @@
       <optional>
         <attribute name="name"/>
       </optional>
+      <optional>
+        <attribute name="state">
+          <choice>
+            <value>connected</value>
+            <value>disconnected</value>
+          </choice>
+        </attribute>
+      </optional>
     </element>
   </define>
   <define name="channel">

src/conf/domain_conf.c

@@ -410,6 +410,11 @@ VIR_ENUM_IMPL(virDomainNetInterfaceLinkState, VIR_DOMAIN_NET_INTERFACE_LINK_STAT
               "up",
               "down")
 
+VIR_ENUM_IMPL(virDomainChrDeviceState, VIR_DOMAIN_CHR_DEVICE_STATE_LAST,
+              "default",
+              "connected",
+              "disconnected");
+
 VIR_ENUM_IMPL(virDomainChrSerialTarget,
               VIR_DOMAIN_CHR_SERIAL_TARGET_TYPE_LAST,
               "isa-serial",
@@ -7857,13 +7862,15 @@ virDomainChrTargetTypeFromString(virDomainChrDefPtr def,
 
 static int
 virDomainChrDefParseTargetXML(virDomainChrDefPtr def,
-                              xmlNodePtr cur)
+                              xmlNodePtr cur,
+                              unsigned int flags)
 {
     int ret = -1;
     unsigned int port;
     char *targetType = virXMLPropString(cur, "type");
     char *addrStr = NULL;
     char *portStr = NULL;
+    char *stateStr = NULL;
 
     if ((def->targetType =
          virDomainChrTargetTypeFromString(def, def->deviceType,
@@ -7920,6 +7927,20 @@ virDomainChrDefParseTargetXML(virDomainChrDefPtr def,
 
         case VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_VIRTIO:
             def->target.name = virXMLPropString(cur, "name");
+
+            if (!(flags & VIR_DOMAIN_XML_INACTIVE) &&
+                (stateStr = virXMLPropString(cur, "state"))) {
+                int tmp;
+
+                if ((tmp = virDomainChrDeviceStateTypeFromString(stateStr)) <= 0) {
+                    virReportError(VIR_ERR_XML_ERROR,
+                                   _("invalid channel state value '%s'"),
+                                   stateStr);
+                    goto error;
+                }
+
+                def->state = tmp;
+            }
             break;
         }
         break;
@@ -7948,6 +7969,7 @@ virDomainChrDefParseTargetXML(virDomainChrDefPtr def,
     VIR_FREE(targetType);
     VIR_FREE(addrStr);
     VIR_FREE(portStr);
+    VIR_FREE(stateStr);
 
     return ret;
 }
@@ -8323,7 +8345,7 @@ virDomainChrDefParseXML(xmlXPathContextPtr ctxt,
         if (cur->type == XML_ELEMENT_NODE) {
             if (xmlStrEqual(cur->name, BAD_CAST "target")) {
                 seenTarget = true;
-                if (virDomainChrDefParseTargetXML(def, cur) < 0)
+                if (virDomainChrDefParseTargetXML(def, cur, flags) < 0)
                     goto error;
             }
         }
@@ -17520,13 +17542,18 @@ virDomainChrDefFormat(virBufferPtr buf,
             break;
         }
 
-        case VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_VIRTIO: {
+        case VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_VIRTIO:
             if (def->target.name)
                 virBufferEscapeString(buf, " name='%s'", def->target.name);
+
+            if (def->state != VIR_DOMAIN_CHR_DEVICE_STATE_DEFAULT &&
+                !(flags & VIR_DOMAIN_XML_INACTIVE)) {
+                virBufferAsprintf(buf, " state='%s'",
+                                  virDomainChrDeviceStateTypeToString(def->state));
+            }
             break;
         }
 
-        }
         virBufferAddLit(buf, "/>\n");
         break;
     }

src/conf/domain_conf.h

@@ -990,6 +990,16 @@ struct _virDomainNetDef {
  * by libvirt, and cannot be used for a persistent network name.  */
 # define VIR_NET_GENERATED_PREFIX "vnet"
 
+typedef enum {
+    VIR_DOMAIN_CHR_DEVICE_STATE_DEFAULT = 0,
+    VIR_DOMAIN_CHR_DEVICE_STATE_CONNECTED,
+    VIR_DOMAIN_CHR_DEVICE_STATE_DISCONNECTED,
+
+    VIR_DOMAIN_CHR_DEVICE_STATE_LAST
+} virDomainChrDeviceState;
+
+VIR_ENUM_DECL(virDomainChrDeviceState)
+
 typedef enum {
     VIR_DOMAIN_CHR_DEVICE_TYPE_PARALLEL = 0,
     VIR_DOMAIN_CHR_DEVICE_TYPE_SERIAL,
@@ -1113,6 +1123,8 @@ struct _virDomainChrDef {
         char *name; /* virtio */
     } target;
 
+    virDomainChrDeviceState state;
+
     virDomainChrSourceDef source;
 
     virDomainDeviceInfo info;

tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-state.args

+LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=none \
+/usr/bin/qemu -S -M pc -m 214 -smp 1 -nographic -nodefconfig -nodefaults \
+-chardev socket,id=charmonitor,path=/tmp/test-monitor,server,nowait \
+-mon chardev=charmonitor,id=monitor,mode=readline \
+-no-acpi -boot c \
+-device virtio-serial-pci,id=virtio-serial1,bus=pci.0,addr=0xa \
+-usb -hda /dev/HostVG/QEMUGuest1 \
+-chardev pty,id=charchannel0 \
+-device virtserialport,bus=virtio-serial1.0,nr=3,chardev=charchannel0,\
+id=channel0,name=org.linux-kvm.port.foo \
+-chardev pty,id=charchannel1 \
+-device virtserialport,bus=virtio-serial1.0,nr=4,chardev=charchannel1,\
+id=channel1,name=org.linux-kvm.port.foo1 \
+-chardev pty,id=charchannel2 \
+-device virtserialport,bus=virtio-serial1.0,nr=5,chardev=charchannel2,\
+id=channel2,name=org.linux-kvm.port.foo2 \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-state.xml

+<domain type='qemu' id='2'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>219100</memory>
+  <currentMemory unit='KiB'>219100</currentMemory>
+  <vcpu placement='static' cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='usb' index='0'/>
+    <controller type='ide' index='0'/>
+    <controller type='virtio-serial' index='1'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo' state='connected'/>
+      <address type='virtio-serial' controller='1' bus='0' port='3'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo1' state='disconnected'/>
+      <address type='virtio-serial' controller='1' bus='0' port='4'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo2'/>
+      <address type='virtio-serial' controller='1' bus='0' port='5'/>
+    </channel>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2argvtest.c

@@ -1070,6 +1070,8 @@ mymain(void)
             QEMU_CAPS_CHARDEV, QEMU_CAPS_DEVICE, QEMU_CAPS_NODEFCONFIG);
     DO_TEST("channel-virtio",
             QEMU_CAPS_DEVICE, QEMU_CAPS_CHARDEV, QEMU_CAPS_NODEFCONFIG);
+    DO_TEST("channel-virtio-state",
+            QEMU_CAPS_DEVICE, QEMU_CAPS_CHARDEV, QEMU_CAPS_NODEFCONFIG);
     DO_TEST("channel-virtio-auto",
             QEMU_CAPS_DEVICE, QEMU_CAPS_CHARDEV, QEMU_CAPS_NODEFCONFIG);
     DO_TEST("console-virtio",

tests/qemuxml2xmloutdata/qemuxml2xmlout-channel-virtio-state-active.xml

+<domain type='qemu' id='2'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>219100</memory>
+  <currentMemory unit='KiB'>219100</currentMemory>
+  <vcpu placement='static' cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <backingStore/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='usb' index='0'/>
+    <controller type='ide' index='0'/>
+    <controller type='virtio-serial' index='1'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo' state='connected'/>
+      <address type='virtio-serial' controller='1' bus='0' port='3'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo1' state='disconnected'/>
+      <address type='virtio-serial' controller='1' bus='0' port='4'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo2'/>
+      <address type='virtio-serial' controller='1' bus='0' port='5'/>
+    </channel>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2xmloutdata/qemuxml2xmlout-channel-virtio-state-inactive.xml

+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>219100</memory>
+  <currentMemory unit='KiB'>219100</currentMemory>
+  <vcpu placement='static' cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='usb' index='0'/>
+    <controller type='ide' index='0'/>
+    <controller type='virtio-serial' index='1'>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'/>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo'/>
+      <address type='virtio-serial' controller='1' bus='0' port='3'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo1'/>
+      <address type='virtio-serial' controller='1' bus='0' port='4'/>
+    </channel>
+    <channel type='pty'>
+      <target type='virtio' name='org.linux-kvm.port.foo2'/>
+      <address type='virtio-serial' controller='1' bus='0' port='5'/>
+    </channel>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2xmltest.c

@@ -288,6 +288,7 @@ mymain(void)
     DO_TEST("console-virtio-many");
     DO_TEST("channel-guestfwd");
     DO_TEST("channel-virtio");
+    DO_TEST_DIFFERENT("channel-virtio-state");
 
     DO_TEST("hostdev-usb-address");
     DO_TEST("hostdev-pci-address");