[libvirt PATCH v2 1/5] conf: add support for <acpi index='NNN'/> for PCI devices

Daniel P. Berrangé berrange at redhat.com
Wed Apr 7 16:24:36 UTC 2021


PCI devices can be associated with a unique integer index that is
exposed via ACPI. In Linux OS with systemd, this value is used for
provide a NIC device naming scheme that is stable across changes
in PCI slot configuration.

Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---
 docs/formatdomain.rst         |  7 ++++
 docs/schemas/domaincommon.rng | 73 +++++++++++++++++++++++++++++++++++
 src/conf/device_conf.h        |  3 ++
 src/conf/domain_conf.c        | 19 +++++++++
 4 files changed, 102 insertions(+)

diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 782ebc8564..29d2e02da1 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -4363,6 +4363,7 @@ Network interfaces
        <mac address='52:54:00:5d:c7:9e'/>
        <boot order='1'/>
        <rom bar='off'/>
+       <acpi index='4'/>
      </interface>
    </devices>
    ...
@@ -4389,6 +4390,12 @@ when it's in the reserved VMware range by adding a ``type="static"`` attribute
 to the ``<mac/>`` element. Note that this attribute is useless if the provided
 MAC address is outside of the reserved VMWare ranges.
 
+:since:`Since 7.3.0`, one can set the ACPI index against network interfaces.
+With some operating systems (eg Linux with systemd), the ACPI index is used
+to provide network interface device naming, that is stable across changes
+in PCI addresses assigned to the device. This value is required to be unique
+across all devices and be between 1 and (16*1024-1).
+
 :anchor:`<a id="elementsNICSVirtual"/>`
 
 Virtual network
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 73ce253821..99cd873832 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -1444,6 +1444,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -2435,6 +2438,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -2863,6 +2869,9 @@
           <optional>
             <ref name="alias"/>
           </optional>
+          <optional>
+            <ref name="acpi"/>
+          </optional>
           <optional>
             <ref name="address"/>
           </optional>
@@ -3520,6 +3529,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -4146,6 +4158,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -4286,6 +4301,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -4538,6 +4556,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -4942,6 +4963,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -5011,6 +5035,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5043,6 +5070,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5121,6 +5151,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5165,6 +5198,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -5192,6 +5228,9 @@
       <optional>
         <ref name="alias"/>
       </optional>
+      <optional>
+        <ref name="acpi"/>
+      </optional>
       <optional>
         <ref name="address"/>
       </optional>
@@ -5287,6 +5326,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <element name="driver">
             <ref name="virtioOptions"/>
@@ -5389,6 +5431,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5404,6 +5449,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5423,6 +5471,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -5454,6 +5505,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="deviceBoot"/>
         </optional>
@@ -6425,6 +6479,16 @@
     </element>
   </define>
 
+  <define name="acpi">
+    <element name="acpi">
+      <optional>
+        <attribute name="index">
+          <ref name="unsignedInt"/>
+        </attribute>
+      </optional>
+    </element>
+  </define>
+
   <define name="memorydev">
     <element name="memory">
       <attribute name="model">
@@ -6463,6 +6527,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
       </interleave>
     </element>
   </define>
@@ -6554,6 +6621,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
@@ -7546,6 +7616,9 @@
         <optional>
           <ref name="alias"/>
         </optional>
+        <optional>
+          <ref name="acpi"/>
+        </optional>
         <optional>
           <ref name="address"/>
         </optional>
diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
index a51bdf10ee..af9a43bff2 100644
--- a/src/conf/device_conf.h
+++ b/src/conf/device_conf.h
@@ -159,6 +159,9 @@ struct _virDomainDeviceInfo {
     /* bootIndex is only used for disk, network interface, hostdev
      * and redirdev devices */
     unsigned int bootIndex;
+    /* Valid for any PCI device. Can be used for NIC to get
+     * stable numbering in Linux */
+    unsigned int acpiIndex;
 
     /* pciConnectFlags is only used internally during address
      * assignment, never saved and never reported.
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index f93af0a85c..83415f9271 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -6335,6 +6335,9 @@ virDomainDeviceInfoFormat(virBufferPtr buf,
         virBufferAddLit(buf, "/>\n");
     }
 
+    if (info->acpiIndex != 0)
+        virBufferAsprintf(buf, "<acpi index='%u'/>\n", info->acpiIndex);
+
     if (info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE ||
         info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_S390)
         /* We're done here */
@@ -6661,6 +6664,7 @@ virDomainDeviceInfoParseXML(virDomainXMLOptionPtr xmlopt,
     g_autofree char *romenabled = NULL;
     g_autofree char *rombar = NULL;
     g_autofree char *aliasStr = NULL;
+    g_autofree char *acpiIndex = NULL;
     VIR_XPATH_NODE_AUTORESTORE(ctxt)
 
     virDomainDeviceInfoClear(info);
@@ -6709,6 +6713,14 @@ virDomainDeviceInfoParseXML(virDomainXMLOptionPtr xmlopt,
         }
     }
 
+    acpiIndex = virXPathString("string(./acpi/@index)", ctxt);
+    if (acpiIndex &&
+        virStrToLong_ui(acpiIndex, NULL, 10, &info->acpiIndex) < 0) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Cannot parse ACPI index value '%s'"), acpiIndex);
+        goto cleanup;
+    }
+
     if ((address = virXPathNode("./address", ctxt)) &&
         virDomainDeviceAddressParseXML(address, info) < 0)
         goto cleanup;
@@ -22193,6 +22205,13 @@ virDomainDeviceInfoCheckABIStability(virDomainDeviceInfoPtr src,
         break;
     }
 
+    if (src->acpiIndex != dst->acpiIndex) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("Target ACPI index '%u' does not match source '%u'"),
+                       dst->acpiIndex, src->acpiIndex);
+        return false;
+    }
+
     return true;
 }
 
-- 
2.30.2




More information about the libvir-list mailing list