Add unique_id to nodedev output

Add an optional unique_id parameter to nodedev.  Allows for easier lookup
and display of the unique_id value in order to document for use with
scsi_host code.

docs/formatnode.html.in

@@ -195,6 +195,17 @@
             <dl>
               <dt><code>host</code></dt>
               <dd>The SCSI host number.</dd>
+              <dt><code>unique_id</code></dt>
+              <dd>On input, this optionally provides the value from the
+                'unique_id' file found in the scsi_host's directory. To
+                view the values of all 'unique_id' files, use <code>find -H
+                /sys/class/scsi_host/host{0..9}/unique_id |
+                xargs grep '[0-9]'</code>. On output, if the unique_id
+                file exists, the value from the file will be displayed.
+                This can be used in order to help uniquely identify the
+                scsi_host adapter in a <a href="formatstorage.html">
+                Storage Pool</a>. <span class="since">Since 1.2.7</span>
+              </dd>
               <dt><code>capability</code></dt>
               <dd>Current capabilities include "vports_ops" (indicates
                 vport operations are supported) and "fc_host". "vport_ops"

docs/schemas/nodedev.rng

@@ -339,6 +339,12 @@
       <ref name='unsignedLong'/>
     </element>
 
+    <optional>
+      <element name='unique_id'>
+        <ref name='positiveInteger'/>
+      </element>
+    </optional>
+
     <optional>
       <zeroOrMore>
         <element name='capability'>

src/conf/node_device_conf.c

@@ -442,6 +442,9 @@ char *virNodeDeviceDefFormat(const virNodeDeviceDef *def)
         case VIR_NODE_DEV_CAP_SCSI_HOST:
             virBufferAsprintf(&buf, "<host>%d</host>\n",
                               data->scsi_host.host);
+            if (data->scsi_host.unique_id != -1)
+                virBufferAsprintf(&buf, "<unique_id>%d</unique_id>\n",
+                                  data->scsi_host.unique_id);
             if (data->scsi_host.flags & VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST) {
                 virBufferAddLit(&buf, "<capability type='fc_host'>\n");
                 virBufferAdjustIndent(&buf, 2);
@@ -826,12 +829,20 @@ virNodeDevCapSCSIHostParseXML(xmlXPathContextPtr ctxt,
     orignode = ctxt->node;
     ctxt->node = node;
 
-    if (create == EXISTING_DEVICE &&
-        virNodeDevCapsDefParseULong("number(./host[1])", ctxt,
-                                    &data->scsi_host.host, def,
-                                    _("no SCSI host ID supplied for '%s'"),
-                                    _("invalid SCSI host ID supplied for '%s'")) < 0) {
-        goto out;
+    if (create == EXISTING_DEVICE) {
+        if (virNodeDevCapsDefParseULong("number(./host[1])", ctxt,
+                                        &data->scsi_host.host, def,
+                                        _("no SCSI host ID supplied for '%s'"),
+                                        _("invalid SCSI host ID supplied for '%s'")) < 0) {
+            goto out;
+        }
+        /* Optional unique_id value */
+        data->scsi_host.unique_id = -1;
+        if (virNodeDevCapsDefParseIntOptional("number(./unique_id[1])", ctxt,
+                                              &data->scsi_host.unique_id, def,
+                                              _("invalid unique_id supplied for '%s'")) < 0) {
+            goto out;
+        }
     }
 
     if ((n = virXPathNodeSet("./capability", ctxt, &nodes)) < 0) {

src/conf/node_device_conf.h

@@ -171,6 +171,7 @@ struct _virNodeDevCapsDef {
         } net;
         struct {
             unsigned int host;
+            int unique_id;
             char *wwnn;
             char *wwpn;
             char *fabric_wwn;

src/node_device/node_device_linux_sysfs.c

@@ -47,6 +47,12 @@ detect_scsi_host_caps(union _virNodeDevCapData *d)
     char *vports = NULL;
     int ret = -1;
 
+    if (virReadSCSIUniqueId(NULL, d->scsi_host.host,
+                            &d->scsi_host.unique_id) < 0) {
+        VIR_DEBUG("Failed to read unique_id for host%d", d->scsi_host.host);
+        d->scsi_host.unique_id = -1;
+    }
+
     VIR_DEBUG("Checking if host%d is an FC HBA", d->scsi_host.host);
 
     if (virIsCapableFCHost(NULL, d->scsi_host.host)) {

src/test/test_driver.c

@@ -6087,14 +6087,15 @@ testNodeDeviceCreateXML(virConnectPtr conn,
     if (VIR_STRDUP(def->name, wwpn) < 0)
         goto cleanup;
 
-    /* Fill in a random 'host' value, since this would also come from
-     * the backend */
+    /* Fill in a random 'host' and 'unique_id' value,
+     * since this would also come from the backend */
     caps = def->caps;
     while (caps) {
         if (caps->type != VIR_NODE_DEV_CAP_SCSI_HOST)
             continue;
 
         caps->data.scsi_host.host = virRandomBits(10);
+        caps->data.scsi_host.unique_id = 2;
         caps = caps->next;
     }
 

tests/nodedevschemadata/pci_8086_27c5_scsi_host_0_unique_id.xml

@@ -0,0 +1,8 @@
+<device>
+  <name>pci_8086_27c5_scsi_host_0</name>
+  <parent>pci_8086_27c5</parent>
+  <capability type='scsi_host'>
+    <host>1</host>
+    <unique_id>2</unique_id>
+  </capability>
+</device>

tests/nodedevxml2xmltest.c

@@ -82,6 +82,7 @@ mymain(void)
     DO_TEST("pci_1002_71c4");
     DO_TEST("pci_8086_10c9_sriov_pf");
     DO_TEST("pci_8086_27c5_scsi_host_0");
+    DO_TEST("pci_8086_27c5_scsi_host_0_unique_id");
     DO_TEST("pci_8086_27c5_scsi_host_scsi_device_lun0");
     DO_TEST("pci_8086_27c5_scsi_host_scsi_host");
     DO_TEST("pci_8086_27c5_scsi_host");