[PATCH v1 1/4] conf: add snapshotName attribute for internal disk snapshot

[Or Ozeri <oro@xxxxxxxxxx>]

Add a new attribute to snapshot disks XML element,
which allows specifying the name that will be used to refer
to internal snapshots.

Signed-off-by: Or Ozeri <oro@xxxxxxxxxx>
---
 docs/formatsnapshot.rst             |  5 +++++
 src/conf/schemas/domainsnapshot.rng |  4 ++++
 src/conf/snapshot_conf.c            | 27 +++++++++++++++++++++++++++
 src/conf/snapshot_conf.h            |  2 ++
 4 files changed, 38 insertions(+)

diff --git a/docs/formatsnapshot.rst b/docs/formatsnapshot.rst
index 085c712053..d98066dd8c 100644
--- a/docs/formatsnapshot.rst
+++ b/docs/formatsnapshot.rst
@@ -145,6 +145,11 @@ The top-level ``domainsnapshot`` element may contain the following elements:
       driver and supported values are ``file``, ``block`` and ``network``
       :since:`(since 1.2.2)`.
 
+      :since:`Since 9.1.0` the ``disk`` element supports an optional attribute
+            ``snapshotName`` if the ``snapshot`` attribute is set to ``internal``. This
+            attribute specifies the name that will be used to refer to the
+            internal disk snapshot.
+
       ``source``
 
          If the snapshot mode is external (whether specified or inherited),
diff --git a/src/conf/schemas/domainsnapshot.rng b/src/conf/schemas/domainsnapshot.rng
index 4048266f1d..19f097d2b3 100644
--- a/src/conf/schemas/domainsnapshot.rng
+++ b/src/conf/schemas/domainsnapshot.rng
@@ -209,6 +209,10 @@
           <value>manual</value>
         </attribute>
       </choice>
+      <optional>
+        <attribute name="snapshotName">
+        </attribute>
+      </optional>
     </element>
   </define>
 
diff --git a/src/conf/snapshot_conf.c b/src/conf/snapshot_conf.c
index 9bf3c78353..58a6afa26d 100644
--- a/src/conf/snapshot_conf.c
+++ b/src/conf/snapshot_conf.c
@@ -150,6 +150,8 @@ virDomainSnapshotDiskDefParseXML(xmlNodePtr node,
                               VIR_STORAGE_TYPE_FILE) < 0)
         return -1;
 
+    def->snapshot_name = virXMLPropString(node, "snapshotName");
+
     if (src->type == VIR_STORAGE_TYPE_VOLUME ||
         src->type == VIR_STORAGE_TYPE_DIR) {
         virReportError(VIR_ERR_XML_ERROR,
@@ -192,6 +194,10 @@ virDomainSnapshotDiskDefParseXML(xmlNodePtr node,
         (src->path || src->format))
         def->snapshot = VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
 
+    if (def->snapshot == VIR_DOMAIN_SNAPSHOT_LOCATION_DEFAULT &&
+        def->snapshot_name)
+        def->snapshot = VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL;
+
     def->name = g_steal_pointer(&name);
     def->src = g_steal_pointer(&src);
 
@@ -670,6 +676,15 @@ virDomainSnapshotAlignDisks(virDomainSnapshotDef *snapdef,
             return -1;
         }
 
+        if (snapdisk->snapshot_name &&
+            snapdisk->snapshot != VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                           _("snapshotName for disk '%s' requires "
+                             "use of internal snapshot mode"),
+                           snapdisk->name);
+            return -1;
+        }
+
         if (snapdisk->src->path &&
             snapdisk->snapshot != VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
@@ -714,6 +729,16 @@ virDomainSnapshotAlignDisks(virDomainSnapshotDef *snapdef,
     if (virDomainSnapshotDefAssignExternalNames(snapdef) < 0)
         return -1;
 
+    /* set default snapshot name for internal snapshots */
+    for (i = 0; i < snapdef->ndisks; i++) {
+        virDomainSnapshotDiskDef * disk = &snapdef->disks[i];
+
+        if (disk->snapshot == VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL &&
+            !disk->snapshot_name) {
+            disk->snapshot_name = g_strdup(snapdef->parent.name);
+        }
+    }
+
     return 0;
 }
 
@@ -748,6 +773,8 @@ virDomainSnapshotDiskDefFormat(virBuffer *buf,
     if (disk->snapshot > 0)
         virBufferAsprintf(&attrBuf, " snapshot='%s'",
                           virDomainSnapshotLocationTypeToString(disk->snapshot));
+    if (disk->snapshot_name)
+        virBufferAsprintf(&attrBuf, " snapshotName='%s'", disk->snapshot_name);
 
     if (disk->snapshotDeleteInProgress)
         virBufferAddLit(&childBuf, "<snapshotDeleteInProgress/>\n");
diff --git a/src/conf/snapshot_conf.h b/src/conf/snapshot_conf.h
index 96c77ef42b..c133c105c7 100644
--- a/src/conf/snapshot_conf.h
+++ b/src/conf/snapshot_conf.h
@@ -57,6 +57,8 @@ struct _virDomainSnapshotDiskDef {
     /* details of wrapper external file. src is always non-NULL.
      * XXX optimize this to allow NULL for internal snapshots? */
     virStorageSource *src;
+
+    char *snapshot_name; /* snapshot name for internal snapshots */
 };
 
 void
-- 
2.25.1