Configure and use per-vm alsa pcm device with softvol control

diff --git a/scripts/qemu-dm-wrapper b/scripts/qemu-dm-wrapper
index 26bc7c2402df97cb19f27b07082b66963ae5b20d..a71313d332acd978285b214882ff0d13e07e7944 100644 (file)
--- a/scripts/qemu-dm-wrapper
+++ b/scripts/qemu-dm-wrapper
@@ -3,6 +3,24 @@
 DOMID=$1
 shift 2
 
+# configure and use per-vm alsa pcm device with softvol control
+ALSA_VMID=$DOMID
+cat >/tmp/alsa-vm-${ALSA_VMID}.conf <<END
+pcm.vm-${ALSA_VMID} {
+  type softvol
+  slave {
+    pcm "dmix"
+  }
+  control {
+    name "vm-${ALSA_VMID}"
+    card 0
+  }
+}
+END
+export ALSA_CONFIG_PATH=/usr/share/alsa/alsa.conf:/tmp/alsa-vm-${ALSA_VMID}.conf
+export QEMU_ALSA_DAC_DEV=plug:vm-${ALSA_VMID}
+export QEMU_ALSA_VOL_CTRL=vm-${ALSA_VMID}
+
 echo Using domid: $DOMID >> /tmp/qemu.$DOMID
 echo Arguments: $* >> /tmp/qemu.$DOMID
 xenstore-write /local/domain/$DOMID/qemu-pid $$