nodedev: add <uuid> element to mdev caps

It will be useful to be able to specify a particular UUID for a mediated
device when defining the node device. To accomodate that, allow this to
be specified in the xml schema. This patch also parses and formats that
value to the xml, but does not yet use it.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>

docs/schemas/nodedev.rng

@@ -606,27 +606,34 @@
   </define>
 
   <define name="capmdev">
-    <attribute name="type">
+    <interleave>
-      <value>mdev</value>
+      <attribute name="type">
-    </attribute>
+        <value>mdev</value>
-    <element name="type">
-      <attribute name="id">
-        <data type="string"/>
       </attribute>
-    </element>
+      <element name="type">
-    <optional>
+        <attribute name="id">
-      <element name="iommuGroup">
+          <data type="string"/>
-        <attribute name="number">
-          <ref name="unsignedInt"/>
         </attribute>
       </element>
-    </optional>
+      <optional>
-    <zeroOrMore>
+        <element name="iommuGroup">
-      <element name="attr">
+          <attribute name="number">
-        <attribute name="name"/>
+            <ref name="unsignedInt"/>
-        <attribute name="value"/>
+          </attribute>
-      </element>
+        </element>
-    </zeroOrMore>
+      </optional>
+      <optional>
+        <element name="uuid">
+          <ref name="UUID"/>
+        </element>
+      </optional>
+      <zeroOrMore>
+        <element name="attr">
+          <attribute name="name"/>
+          <attribute name="value"/>
+        </element>
+      </zeroOrMore>
+    </interleave>
   </define>
 
   <define name="capccwdev">

src/conf/node_device_conf.c

@@ -527,6 +527,7 @@ virNodeDeviceCapMdevDefFormat(virBufferPtr buf,
     size_t i;
 
     virBufferEscapeString(buf, "<type id='%s'/>\n", data->mdev.type);
+    virBufferEscapeString(buf, "<uuid>%s</uuid>\n", data->mdev.uuid);
     virBufferAsprintf(buf, "<iommuGroup number='%u'/>\n",
                       data->mdev.iommuGroupNumber);
 
@@ -1948,6 +1949,7 @@ virNodeDevCapMdevParseXML(xmlXPathContextPtr ctxt,
     int nattrs = 0;
     g_autofree xmlNodePtr *attrs = NULL;
     size_t i;
+    g_autofree char *uuidstr = NULL;
 
     ctxt->node = node;
 
@@ -1957,6 +1959,18 @@ virNodeDevCapMdevParseXML(xmlXPathContextPtr ctxt,
         return -1;
     }
 
+    if ((uuidstr = virXPathString("string(./uuid[1])", ctxt))) {
+        unsigned char uuidbuf[VIR_UUID_BUFLEN];
+        /* make sure that the provided uuid is valid */
+        if (virUUIDParse(uuidstr, uuidbuf) < 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Invalid uuid '%s' for new mdev device"), uuidstr);
+            return -1;
+        }
+        mdev->uuid = g_new0(char, VIR_UUID_STRING_BUFLEN);
+        virUUIDFormat(uuidbuf, mdev->uuid);
+    }
+
     /* 'iommuGroup' is optional, only report an error if the supplied value is
      * invalid (-2), not if it's missing (-1) */
     if (virXPathUInt("number(./iommuGroup[1]/@number)",

tests/nodedevmdevctldata/mdevctl-list-multiple.out.xml

@@ -3,6 +3,7 @@
   <parent>0000:00:02.0</parent>
   <capability type='mdev'>
     <type id='i915-GVTg_V5_4'/>
+    <uuid>200f228a-c80a-4d50-bfb7-f5a0e4e34045</uuid>
     <iommuGroup number='0'/>
   </capability>
 </device>
@@ -11,6 +12,7 @@
   <parent>0000:00:02.0</parent>
   <capability type='mdev'>
     <type id='i915-GVTg_V5_4'/>
+    <uuid>de807ffc-1923-4d5f-b6c9-b20ecebc6d4b</uuid>
     <iommuGroup number='0'/>
   </capability>
 </device>
@@ -19,6 +21,7 @@
   <parent>0000:00:02.0</parent>
   <capability type='mdev'>
     <type id='i915-GVTg_V5_8'/>
+    <uuid>435722ea-5f43-468a-874f-da34f1217f13</uuid>
     <iommuGroup number='0'/>
     <attr name='testattr' value='42'/>
   </capability>
@@ -28,6 +31,7 @@
   <parent>matrix</parent>
   <capability type='mdev'>
     <type id='vfio_ap-passthrough'/>
+    <uuid>783e6dbb-ea0e-411f-94e2-717eaad438bf</uuid>
     <iommuGroup number='0'/>
     <attr name='assign_adapter' value='5'/>
     <attr name='assign_adapter' value='6'/>