[PATCH qemu-server v5 2/4] hotplug: remove iothread with virtio-scsi controller together

[Dominik Csapak <d.csapak@proxmox.com>]

With virtio-scsi-single, the iothread is used by the controller
'virtioscsiN' and not by the disk 'scsiN', but it was removed when
unplugging the disk (which was done after removal of the controller).

Remove the iothread together with the controller instead, and decide
whether to remove it by checking the iothreads that actually exist
instead of the config. This way, the controller can be unplugged
without having the config of its disk, which is necessary for cleaning
up after a failed hotplug in a following commit.

Since an 'iothread-<id>' object is only used by the device with that
id, it is safe to remove it once the device is gone.

Note that this now executes an additional qmp command for disks that
don't have an iothread in the config, but since this is not called that
often (once per disk config change) it should be ok.

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 src/PVE/QemuServer.pm | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/src/PVE/QemuServer.pm b/src/PVE/QemuServer.pm
index 6ac3c685..38a4e4f8 100644
--- a/src/PVE/QemuServer.pm
+++ b/src/PVE/QemuServer.pm
@@ -3972,25 +3972,20 @@ sub vm_deviceunplug {
         qemu_devicedel($vmid, $deviceid);
         qemu_devicedelverify($vmid, $deviceid);
     } elsif ($deviceid =~ m/^(virtio)(\d+)$/) {
-        my $device = parse_drive($deviceid, $conf->{$deviceid});
-
         qemu_devicedel($vmid, $deviceid);
         qemu_devicedelverify($vmid, $deviceid);
         qemu_drivedel($vmid, $deviceid);
-        qemu_iothread_del($vmid, $deviceid, $device);
+        qemu_iothread_del($vmid, $deviceid);
     } elsif ($deviceid =~ m/^(virtioscsi|scsihw)(\d+)$/) {
         qemu_devicedel($vmid, $deviceid);
         qemu_devicedelverify($vmid, $deviceid, 15);
+        qemu_iothread_del($vmid, $deviceid) if $deviceid =~ m/^virtioscsi\d+$/;
     } elsif ($deviceid =~ m/^(scsi)(\d+)$/) {
-        my $device = parse_drive($deviceid, $conf->{$deviceid});
-
         qemu_devicedel($vmid, $deviceid);
         qemu_devicedelverify($vmid, $deviceid);
         qemu_drivedel($vmid, $deviceid);
+        # the iothread of a virtio-scsi-single disk belongs to its controller and is removed there
         qemu_deletescsihw($conf, $vmid, $deviceid);
-
-        qemu_iothread_del($vmid, "virtioscsi$device->{index}", $device)
-            if $conf->{scsihw} && ($conf->{scsihw} eq 'virtio-scsi-single');
     } elsif ($deviceid =~ m/^(net)(\d+)$/) {
         qemu_devicedel($vmid, $deviceid);
         qemu_devicedelverify($vmid, $deviceid);
@@ -4031,12 +4026,10 @@ sub qemu_iothread_add {
 }
 
 sub qemu_iothread_del {
-    my ($vmid, $deviceid, $device) = @_;
+    my ($vmid, $deviceid) = @_;
 
-    if ($device->{iothread}) {
-        my $iothreads = vm_iothreads_list($vmid);
-        qemu_objectdel($vmid, "iothread-$deviceid") if $iothreads->{"iothread-$deviceid"};
-    }
+    my $iothreads = vm_iothreads_list($vmid);
+    qemu_objectdel($vmid, "iothread-$deviceid") if $iothreads->{"iothread-$deviceid"};
 }
 
 sub qemu_driveadd {
-- 
2.47.3