qemu: command: format disk source commandline for -blockdev

Format the backing chain onto the commandline using the 'json' syntax
with -blockdev.

The command line formatter needs only minor tweaks to add the new
entries but we now need to initialize the structures that are used for
every layer of the backing chain.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/qemu/qemu_command.c

@@ -2262,6 +2262,8 @@ static int
 qemuBuildBlockStorageSourceAttachDataCommandline(virCommandPtr cmd,
                                                  qemuBlockStorageSourceAttachDataPtr data)
 {
+    char *tmp;
+
     if (qemuBuildObjectCommandline(cmd, data->prmgrProps) < 0 ||
         qemuBuildObjectCommandline(cmd, data->authsecretProps) < 0 ||
         qemuBuildObjectCommandline(cmd, data->encryptsecretProps) < 0 ||
@@ -2271,6 +2273,22 @@ qemuBuildBlockStorageSourceAttachDataCommandline(virCommandPtr cmd,
     if (data->driveCmd)
         virCommandAddArgList(cmd, "-drive", data->driveCmd, NULL);
 
+    if (data->storageProps) {
+        if (!(tmp = virJSONValueToString(data->storageProps, false)))
+            return -1;
+
+        virCommandAddArgList(cmd, "-blockdev", tmp, NULL);
+        VIR_FREE(tmp);
+    }
+
+    if (data->formatProps) {
+        if (!(tmp = virJSONValueToString(data->formatProps, false)))
+            return -1;
+
+        virCommandAddArgList(cmd, "-blockdev", tmp, NULL);
+        VIR_FREE(tmp);
+    }
+
     return 0;
 }
 
@@ -2280,20 +2298,70 @@ qemuBuildDiskSourceCommandLine(virCommandPtr cmd,
                                virDomainDiskDefPtr disk,
                                virQEMUCapsPtr qemuCaps)
 {
-    qemuBlockStorageSourceAttachDataPtr data = NULL;
+    qemuBlockStorageSourceAttachDataPtr *data = NULL;
+    size_t ndata = 0;
+    qemuBlockStorageSourceAttachDataPtr tmp = NULL;
+    virJSONValuePtr copyOnReadProps = NULL;
+    virStorageSourcePtr n;
+    char *str = NULL;
+    size_t i;
     int ret = -1;
 
-    if (!(data = qemuBuildStorageSourceAttachPrepareDrive(disk, qemuCaps)))
-        return -1;
+    if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV)) {
+        if (virStorageSourceIsEmpty(disk->src)) {
+            ret = 0;
+            goto cleanup;
+        }
 
-    if (qemuBuildStorageSourceAttachPrepareCommon(disk->src, data, qemuCaps) < 0 ||
-        qemuBuildBlockStorageSourceAttachDataCommandline(cmd, data) < 0)
-        goto cleanup;
+        for (n = disk->src; virStorageSourceIsBacking(n); n = n->backingStore) {
+            if (!(tmp = qemuBlockStorageSourceAttachPrepareBlockdev(n)))
+                goto cleanup;
+
+            if (qemuBuildStorageSourceAttachPrepareCommon(n, tmp, qemuCaps) < 0)
+                goto cleanup;
+
+            if (VIR_APPEND_ELEMENT(data, ndata, tmp) < 0)
+                goto cleanup;
+        }
+
+        if (disk->copy_on_read == VIR_TRISTATE_SWITCH_ON &&
+            !(copyOnReadProps = qemuBlockStorageGetCopyOnReadProps(disk)))
+            goto cleanup;
+    } else {
+        if (!(tmp = qemuBuildStorageSourceAttachPrepareDrive(disk, qemuCaps)))
+            goto cleanup;
+
+        if (qemuBuildStorageSourceAttachPrepareCommon(disk->src, tmp,
+                                                      qemuCaps) < 0)
+            goto cleanup;
+
+        if (VIR_APPEND_ELEMENT(data, ndata, tmp) < 0)
+            goto cleanup;
+    }
+
+    for (i = ndata; i > 0; i--) {
+        if (qemuBuildBlockStorageSourceAttachDataCommandline(cmd,
+                                                             data[i - 1]) < 0)
+            goto cleanup;
+    }
+
+    if (copyOnReadProps) {
+        if (!(str = virJSONValueToString(copyOnReadProps, false)))
+            goto cleanup;
+
+        virCommandAddArgList(cmd, "-blockdev", str, NULL);
+        VIR_FREE(str);
+    }
 
     ret = 0;
 
  cleanup:
-    qemuBlockStorageSourceAttachDataFree(data);
+    for (i = 0; i < ndata; i++)
+        qemuBlockStorageSourceAttachDataFree(data[i]);
+    VIR_FREE(data);
+    qemuBlockStorageSourceAttachDataFree(tmp);
+    virJSONValueFree(copyOnReadProps);
+    VIR_FREE(str);
     return ret;
 }