[libvirt] [PATCH v2 3/3] qemu: fallback to HMP drive_add/drive_del

[Jiri Denemark]

From: Hu Tao <hutao at cn.fujitsu.com>

fallback to HMP drive_add/drive_del commands if not found in QMP
---
Notes:
    Version 2:
    - check for human-monitor-command availability before calling text
      monitor methods

 src/qemu/qemu_monitor_json.c |   38 ++++++++++++++++++++++++--------------
 1 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index d2d6ba1..6bd03d6 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -2289,11 +2289,19 @@ int qemuMonitorJSONAddDrive(qemuMonitorPtr mon,
     if (!cmd)
         return -1;
 
-    ret = qemuMonitorJSONCommand(mon, cmd, &reply);
+    if ((ret = qemuMonitorJSONCommand(mon, cmd, &reply) < 0))
+        goto cleanup;
 
-    if (ret == 0)
-        ret = qemuMonitorJSONCheckError(cmd, reply);
+    if (qemuMonitorJSONHasError(reply, "CommandNotFound") &&
+        qemuMonitorCheckHMP(mon, "drive_add")) {
+        VIR_DEBUG0("drive_add command not found, trying HMP");
+        ret = qemuMonitorTextAddDrive(mon, drivestr);
+        goto cleanup;
+    }
+
+    ret = qemuMonitorJSONCheckError(cmd, reply);
 
+cleanup:
     virJSONValueFree(cmd);
     virJSONValueFree(reply);
     return ret;
@@ -2314,22 +2322,24 @@ int qemuMonitorJSONDriveDel(qemuMonitorPtr mon,
     if (!cmd)
         return -1;
 
-    ret = qemuMonitorJSONCommand(mon, cmd, &reply);
+    if ((ret = qemuMonitorJSONCommand(mon, cmd, &reply)) < 0)
+        goto cleanup;
 
-    if (ret == 0) {
-        /* See if drive_del isn't supported */
-        if (qemuMonitorJSONHasError(reply, "CommandNotFound")) {
+    if (qemuMonitorJSONHasError(reply, "CommandNotFound")) {
+        if (qemuMonitorCheckHMP(mon, "drive_del")) {
+            VIR_DEBUG0("drive_del command not found, trying HMP");
+            ret = qemuMonitorTextDriveDel(mon, drivestr);
+        } else {
             VIR_ERROR0(_("deleting disk is not supported.  "
                         "This may leak data if disk is reassigned"));
             ret = 1;
-            goto cleanup;
-        } else if (qemuMonitorJSONHasError(reply, "DeviceNotFound")) {
-            /* NB: device not found errors mean the drive was
-             * auto-deleted and we ignore the error */
-            ret = 0;
-        } else {
-            ret = qemuMonitorJSONCheckError(cmd, reply);
         }
+    } else if (qemuMonitorJSONHasError(reply, "DeviceNotFound")) {
+        /* NB: device not found errors mean the drive was
+         * auto-deleted and we ignore the error */
+        ret = 0;
+    } else {
+        ret = qemuMonitorJSONCheckError(cmd, reply);
     }
 
 cleanup:
-- 
1.7.4.1