qemu: hotplug: Skip waiting for tray opening if qemu doesn't notify us

If qemu doesn't support DEVICE_TRAY_MOVED event the code that attempts
to change media would attempt to re-eject the tray even if it wouldn't
be notified when the tray opened. Add a capability bit and skip retrying
for old qemus.

(cherry picked from commit 833ae6b4356934e7b779c4be01bd2bf051930dde)

src/qemu/qemu_capabilities.c

@@ -321,6 +321,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST,
               "qxl-vga.vram64_size_mb", /* 215 */
               "chardev-logfile",
               "debug-threads",
+              "device-tray-moved-event",
     );
 
 
@@ -1493,6 +1494,7 @@ struct virQEMUCapsStringFlags virQEMUCapsEvents[] = {
     { "DEVICE_DELETED", QEMU_CAPS_DEVICE_DEL_EVENT },
     { "MIGRATION", QEMU_CAPS_MIGRATION_EVENT },
     { "VSERPORT_CHANGE", QEMU_CAPS_VSERPORT_CHANGE },
+    { "DEVICE_TRAY_MOVED", QEMU_CAPS_DEVICE_TRAY_MOVED },
 };
 
 struct virQEMUCapsStringFlags virQEMUCapsObjectTypes[] = {

src/qemu/qemu_capabilities.h

@@ -351,6 +351,7 @@ typedef enum {
     QEMU_CAPS_QXL_VGA_VRAM64, /* -device qxl-vga.vram64_size_mb */
     QEMU_CAPS_CHARDEV_LOGFILE, /* -chardev logfile=xxxx */
     QEMU_CAPS_NAME_DEBUG_THREADS, /* Is -name debug-threads= available */
+    QEMU_CAPS_DEVICE_TRAY_MOVED, /* DEVICE_TRAY_MOVED event */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

src/qemu/qemu_hotplug.c

@@ -202,6 +202,15 @@ qemuDomainChangeEjectableMedia(virQEMUDriverPtr driver,
         if (qemuDomainObjExitMonitor(driver, vm) < 0)
             goto cleanup;
 
+        /* skip all retrying if qemu doesn't notify us on tray change */
+        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE_TRAY_MOVED)) {
+            if (rc == 0)
+                break;
+
+            if (rc < 0)
+                goto error;
+        }
+
         if (rc < 0) {
             /* we've already tried, error out */
             if (ejectRetry)

tests/qemucapabilitiesdata/caps_1.2.2-1.caps

@@ -114,4 +114,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_1.3.1-1.caps

@@ -129,4 +129,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_1.4.2-1.caps

@@ -130,4 +130,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_1.5.3-1.caps

@@ -139,4 +139,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_1.6.0-1.caps

@@ -145,4 +145,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_1.6.50-1.caps

@@ -145,4 +145,5 @@
     <flag name='virtio-net'/>
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_2.1.1-1.caps

@@ -163,4 +163,5 @@
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
     <flag name='debug-threads'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_2.4.0-1.caps

@@ -174,4 +174,5 @@
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
     <flag name='debug-threads'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_2.5.0-1.caps

@@ -175,4 +175,5 @@
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
     <flag name='debug-threads'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>

tests/qemucapabilitiesdata/caps_2.6.0-1.caps

@@ -178,4 +178,5 @@
     <flag name='qxl.vram64_size_mb'/>
     <flag name='qxl-vga.vram64_size_mb'/>
     <flag name='debug-threads'/>
+    <flag name='device-tray-moved-event'/>
   </qemuCaps>