conf: Introduce sgio for hostdev

"sgio" is only valid for scsi host device.

docs/formatdomain.html.in

@@ -2414,7 +2414,12 @@
         and <code>virNodeDeviceReAttach</code> (or <code>virsh
         nodedev-reattach</code>) after hot-unplug or stopping the
         guest. For SCSI device, user is responsible to make sure the device
-        is not used by host.</dd>
+        is not used by host.
+        The optional <code>sgio</code> (<span class="since">since 1.0.6</span>)
+        attribute indicates whether the kernel will filter unprivileged
+        SG_IO commands for the disk, valid settings are "filtered" or
+        "unfiltered". Defaults to "filtered".
+      </dd>
       <dt><code>source</code></dt>
       <dd>The source element describes the device as seen from the host.
       The USB device can either be addressed by vendor / product id using the

docs/schemas/domaincommon.rng

@@ -3234,6 +3234,14 @@
     <attribute name="type">
       <value>scsi</value>
     </attribute>
+    <optional>
+      <attribute name="sgio">
+        <choice>
+          <value>filtered</value>
+          <value>unfiltered</value>
+        </choice>
+      </attribute>
+    </optional>
     <element name="source">
       <interleave>
         <ref name="sourceinfoadapter"/>

src/conf/domain_conf.c

@@ -3790,6 +3790,7 @@ virDomainHostdevDefParseXMLSubsys(xmlNodePtr node,
 {
     xmlNodePtr sourcenode;
     char *managed = NULL;
+    char *sgio = NULL;
     char *backendStr = NULL;
     int backend;
     int ret = -1;
@@ -3804,6 +3805,8 @@ virDomainHostdevDefParseXMLSubsys(xmlNodePtr node,
             def->managed = true;
     }
 
+    sgio = virXMLPropString(node, "sgio");
+
     /* @type is passed in from the caller rather than read from the
      * xml document, because it is specified in different places for
      * different kinds of defs - it is an attribute of
@@ -3840,6 +3843,22 @@ virDomainHostdevDefParseXMLSubsys(xmlNodePtr node,
         goto error;
     }
 
+    if (sgio) {
+        if (def->source.subsys.type !=
+            VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI) {
+            virReportError(VIR_ERR_XML_ERROR, "%s",
+                           _("sgio is only supported for scsi host device"));
+            goto error;
+        }
+
+        if ((def->source.subsys.u.scsi.sgio =
+             virDomainDeviceSGIOTypeFromString(sgio)) <= 0) {
+            virReportError(VIR_ERR_XML_ERROR,
+                           _("unknown sgio mode '%s'"), sgio);
+            goto error;
+        }
+    }
+
     switch (def->source.subsys.type) {
     case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI:
         if (virDomainHostdevSubsysPciDefParseXML(sourcenode, def, flags) < 0)
@@ -3878,6 +3897,7 @@ virDomainHostdevDefParseXMLSubsys(xmlNodePtr node,
     ret = 0;
 error:
     VIR_FREE(managed);
+    VIR_FREE(sgio);
     VIR_FREE(backendStr);
     return ret;
 }
@@ -15439,11 +15459,17 @@ virDomainHostdevDefFormat(virBufferPtr buf,
 
     virBufferAsprintf(buf, "    <hostdev mode='%s' type='%s'",
                       mode, type);
-    if (def->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS)
-        virBufferAsprintf(buf, " managed='%s'>\n",
+    if (def->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS) {
+        virBufferAsprintf(buf, " managed='%s'",
                           def->managed ? "yes" : "no");
-    else
-        virBufferAddLit(buf, ">\n");
+
+        if (def->source.subsys.type ==
+            VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI &&
+            def->source.subsys.u.scsi.sgio)
+            virBufferAsprintf(buf, " sgio='%s'",
+                              virDomainDeviceSGIOTypeToString(def->source.subsys.u.scsi.sgio));
+    }
+    virBufferAddLit(buf, ">\n");
 
     virBufferAdjustIndent(buf, 6);
     switch (def->mode) {

src/conf/domain_conf.h

@@ -423,6 +423,7 @@ struct _virDomainHostdevSubsys {
             unsigned bus;
             unsigned target;
             unsigned unit;
+            int sgio; /* enum virDomainDeviceSGIO */
         } scsi;
     } u;
 };

tests/qemuxml2argvdata/qemuxml2argv-hostdev-scsi-sgio.xml

@@ -0,0 +1,35 @@
+<domain type='qemu'>
+  <name>QEMUGuest2</name>
+  <uuid>c7a5fdbd-edaf-9466-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>219100</memory>
+  <currentMemory unit='KiB'>219100</currentMemory>
+  <vcpu placement='static'>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/QEMUGuest2'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='scsi' index='0' model='virtio-scsi'/>
+    <controller type='usb' index='0'/>
+    <controller type='ide' index='0'/>
+    <controller type='pci' index='0' model='pci-root'/>
+    <hostdev mode='subsystem' type='scsi' managed='yes' sgio='unfiltered'>
+      <source>
+        <adapter name='scsi_host0'/>
+        <address bus='0' target='0' unit='0'/>
+      </source>
+      <address type='drive' controller='0' bus='0' target='4' unit='8'/>
+    </hostdev>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2xmltest.c

@@ -295,6 +295,7 @@ mymain(void)
 
     DO_TEST("disk-copy_on_read");
     DO_TEST("hostdev-scsi-shareable");
+    DO_TEST("hostdev-scsi-sgio");
 
     virObjectUnref(driver.caps);
     virObjectUnref(driver.xmlopt);