From c4896d378b921ba6471562d7b17641be121c19d6 Mon Sep 17 00:00:00 2001
From: "Daniel P. Berrange" <berrange@redhat.com>
Date: Thu, 15 Apr 2010 11:35:07 +0100
Subject: [PATCH] Fix CDROM media change for QEMU when using -device syntax

Disk devices in QEMU have two parts, the guest device and the host
backend driver. Historically these two parts have had the same
"unique" name. With the switch to using -device though, they now
have separate names. Thus when changing CDROM media, for guests
using -device syntax, we need to prepend the QEMU_DRIVE_HOST_PREFIX
constant

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Add helper function
  qemuDeviceDriveHostAlias() for building a host backend alias
* src/qemu/qemu_driver.c: Use qemuDeviceDriveHostAlias() to determine
  the host backend alias for performing eject/change commands in the
  monitor
---
 src/qemu/qemu_conf.c   | 20 ++++++++++++++++++++
 src/qemu/qemu_conf.h   |  3 +++
 src/qemu/qemu_driver.c | 22 +++++++++++++++++-----
 3 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index 1a8b4aabb2..0cbedf257d 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -1699,6 +1699,26 @@ static int qemuAssignDeviceDiskAliasLegacy(virDomainDiskDefPtr disk)
 }
 
 
+char *qemuDeviceDriveHostAlias(virDomainDiskDefPtr disk,
+                               unsigned long long qemudCmdFlags)
+{
+    char *ret;
+
+    if (qemudCmdFlags & QEMUD_CMD_FLAG_DEVICE) {
+        if (virAsprintf(&ret, "%s%s", QEMU_DRIVE_HOST_PREFIX, disk->info.alias) < 0) {
+            virReportOOMError();
+            return NULL;
+        }
+    } else {
+        if (!(ret = strdup(disk->info.alias))) {
+            virReportOOMError();
+            return NULL;
+        }
+    }
+    return ret;
+}
+
+
 /* Names used before -drive supported the id= option */
 static int qemuAssignDeviceDiskAliasFixed(virDomainDiskDefPtr disk)
 {
diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index 574709eb07..b2820f0fa2 100644
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -220,6 +220,9 @@ char * qemuBuildNicStr(virDomainNetDefPtr net,
 char * qemuBuildNicDevStr(virDomainNetDefPtr net,
                           int vlan);
 
+char *qemuDeviceDriveHostAlias(virDomainDiskDefPtr disk,
+                               unsigned long long qemudCmdFlags);
+
 /* Both legacy & current support */
 char *qemuBuildDriveStr(virDomainDiskDefPtr disk,
                         int bootable,
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 0189dcf010..7d2f3ef518 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -6552,11 +6552,13 @@ cleanup:
 
 static int qemudDomainChangeEjectableMedia(struct qemud_driver *driver,
                                            virDomainObjPtr vm,
-                                           virDomainDiskDefPtr disk)
+                                           virDomainDiskDefPtr disk,
+                                           unsigned long long qemuCmdFlags)
 {
     virDomainDiskDefPtr origdisk = NULL;
     int i;
     int ret;
+    char *driveAlias = NULL;
 
     origdisk = NULL;
     for (i = 0 ; i < vm->def->ndisks ; i++) {
@@ -6594,6 +6596,9 @@ static int qemudDomainChangeEjectableMedia(struct qemud_driver *driver,
         driver->securityDriver->domainSetSecurityImageLabel(vm, disk) < 0)
         return -1;
 
+    if (!(driveAlias = qemuDeviceDriveHostAlias(origdisk, qemuCmdFlags)))
+        goto error;
+
     qemuDomainObjPrivatePtr priv = vm->privateData;
     qemuDomainObjEnterMonitorWithDriver(driver, vm);
     if (disk->src) {
@@ -6605,10 +6610,10 @@ static int qemudDomainChangeEjectableMedia(struct qemud_driver *driver,
                 format = origdisk->driverType;
         }
         ret = qemuMonitorChangeMedia(priv->mon,
-                                     origdisk->info.alias,
+                                     driveAlias,
                                      disk->src, format);
     } else {
-        ret = qemuMonitorEjectMedia(priv->mon, origdisk->info.alias);
+        ret = qemuMonitorEjectMedia(priv->mon, driveAlias);
     }
     qemuDomainObjExitMonitorWithDriver(driver, vm);
 
@@ -6625,11 +6630,14 @@ static int qemudDomainChangeEjectableMedia(struct qemud_driver *driver,
     disk->src = NULL;
     origdisk->type = disk->type;
 
+    VIR_FREE(driveAlias);
+
     virDomainDiskDefFree(disk);
 
     return ret;
 
 error:
+    VIR_FREE(driveAlias);
     if (driver->securityDriver &&
         driver->securityDriver->domainRestoreSecurityImageLabel &&
         driver->securityDriver->domainRestoreSecurityImageLabel(vm, disk) < 0)
@@ -7434,7 +7442,9 @@ static int qemudDomainAttachDevice(virDomainPtr dom,
         switch (dev->data.disk->device) {
         case VIR_DOMAIN_DISK_DEVICE_CDROM:
         case VIR_DOMAIN_DISK_DEVICE_FLOPPY:
-            ret = qemudDomainChangeEjectableMedia(driver, vm, dev->data.disk);
+            ret = qemudDomainChangeEjectableMedia(driver, vm,
+                                                  dev->data.disk,
+                                                  qemuCmdFlags);
             if (ret == 0)
                 dev->data.disk = NULL;
             break;
@@ -7679,7 +7689,9 @@ static int qemuDomainUpdateDeviceFlags(virDomainPtr dom,
         switch (dev->data.disk->device) {
         case VIR_DOMAIN_DISK_DEVICE_CDROM:
         case VIR_DOMAIN_DISK_DEVICE_FLOPPY:
-            ret = qemudDomainChangeEjectableMedia(driver, vm, dev->data.disk);
+            ret = qemudDomainChangeEjectableMedia(driver, vm,
+                                                  dev->data.disk,
+                                                  qemuCmdFlags);
             if (ret == 0)
                 dev->data.disk = NULL;
             break;