qemu: process: assign node names for user defined backing chains

Prepare the full backing chain by instantiating authentication and TLS
transport secrets and other necessary objects so that we can add the
full backing chain explicitly to qemu. This also includes allocation of
nodenames for the individual backing chain members.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/qemu/qemu_domain.c

@@ -137,6 +137,14 @@ static virClassPtr qemuDomainSaveCookieClass;
 static void qemuDomainLogContextDispose(void *obj);
 static void qemuDomainSaveCookieDispose(void *obj);
 
+
+static int
+qemuDomainPrepareStorageSourceBlockdev(virDomainDiskDefPtr disk,
+                                       virStorageSourcePtr src,
+                                       qemuDomainObjPrivatePtr priv,
+                                       virQEMUDriverConfigPtr cfg);
+
+
 static int
 qemuDomainOnceInit(void)
 {
@@ -8653,6 +8661,10 @@ qemuDomainDetermineDiskChain(virQEMUDriverPtr driver,
 
         if (qemuDomainPrepareDiskSourceData(disk, n, cfg, priv->qemuCaps) < 0)
             goto cleanup;
+
+        if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV) &&
+            qemuDomainPrepareStorageSourceBlockdev(disk, n, priv, cfg) < 0)
+            goto cleanup;
     }
 
     ret = 0;
@@ -13103,6 +13115,62 @@ qemuDomainPrepareDiskSourceLegacy(virDomainDiskDefPtr disk,
 }
 
 
+static int
+qemuDomainPrepareStorageSourceBlockdev(virDomainDiskDefPtr disk,
+                                       virStorageSourcePtr src,
+                                       qemuDomainObjPrivatePtr priv,
+                                       virQEMUDriverConfigPtr cfg)
+{
+    src->id = qemuDomainStorageIdNew(priv);
+
+    if (virAsprintf(&src->nodestorage, "libvirt-%u-storage", src->id) < 0 ||
+        virAsprintf(&src->nodeformat, "libvirt-%u-format", src->id) < 0)
+        return -1;
+
+    if (qemuDomainValidateStorageSource(src, priv->qemuCaps) < 0)
+        return -1;
+
+    if (qemuDomainPrepareDiskSourceData(disk, src, cfg, priv->qemuCaps) < 0)
+        return -1;
+
+    if (qemuDomainSecretStorageSourcePrepare(priv, src,
+                                             src->nodestorage,
+                                             src->nodeformat) < 0)
+        return -1;
+
+    if (qemuDomainPrepareStorageSourcePR(disk->src, priv, src->nodestorage) < 0)
+        return -1;
+
+    if (qemuDomainPrepareStorageSourceTLS(disk->src, cfg, src->nodestorage,
+                                          priv->qemuCaps) < 0)
+        return -1;
+
+    return 0;
+}
+
+
+static int
+qemuDomainPrepareDiskSourceBlockdev(virDomainDiskDefPtr disk,
+                                    qemuDomainObjPrivatePtr priv,
+                                    virQEMUDriverConfigPtr cfg)
+{
+    qemuDomainDiskPrivatePtr diskPriv = QEMU_DOMAIN_DISK_PRIVATE(disk);
+    virStorageSourcePtr n;
+
+    if (disk->copy_on_read == VIR_TRISTATE_SWITCH_ON &&
+        !diskPriv->nodeCopyOnRead &&
+        virAsprintf(&diskPriv->nodeCopyOnRead, "libvirt-CoR-%s", disk->dst) < 0)
+        return -1;
+
+    for (n = disk->src; virStorageSourceIsBacking(n); n = n->backingStore) {
+        if (qemuDomainPrepareStorageSourceBlockdev(disk, n, priv, cfg) < 0)
+            return -1;
+    }
+
+    return 0;
+}
+
+
 int
 qemuDomainPrepareDiskSource(virDomainDiskDefPtr disk,
                             qemuDomainObjPrivatePtr priv,
@@ -13110,8 +13178,13 @@ qemuDomainPrepareDiskSource(virDomainDiskDefPtr disk,
 {
     qemuDomainPrepareDiskCachemode(disk);
 
-    if (qemuDomainPrepareDiskSourceLegacy(disk, priv, cfg) < 0)
-        return -1;
+    if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV)) {
+        if (qemuDomainPrepareDiskSourceBlockdev(disk, priv, cfg) < 0)
+            return -1;
+    } else {
+        if (qemuDomainPrepareDiskSourceLegacy(disk, priv, cfg) < 0)
+            return -1;
+    }
 
     return 0;
 }