[PATCH] qemu: support hotplug cdrom with usb/scsi bus

[Michal Prívozník]

On 7/6/22 11:57, minglei.liu wrote:
> Qemu support hotplug cdrom device with usb or scsi bus,
> just unblock these devices in qemuDomainAttachDeviceDiskLiveInternal
> and qemuDomainDetachPrepDisk.
> 
> Fixes: #261

We like the full URL as it's easily clickable when viewing git log.

> 
> Signed-off-by: minglei.liu <minglei.liu at smartx.com>
> ---
>  src/qemu/qemu_hotplug.c                       | 13 +++-
>  tests/qemuhotplugtest.c                       | 18 ++++++
>  .../qemuhotplug-cdrom-scsi.xml                |  6 ++
>  .../qemuhotplug-cdrom-usb.xml                 |  6 ++
>  .../qemuhotplug-base-live+cdrom-scsi.xml      | 60 +++++++++++++++++++
>  .../qemuhotplug-base-live+cdrom-usb.xml       | 60 +++++++++++++++++++
>  6 files changed, 160 insertions(+), 3 deletions(-)
>  create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-cdrom-scsi.xml
>  create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-cdrom-usb.xml
>  create mode 100644 tests/qemuhotplugtestdomains/qemuhotplug-base-live+cdrom-scsi.xml
>  create mode 100644 tests/qemuhotplugtestdomains/qemuhotplug-base-live+cdrom-usb.xml
> 
> diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
> index 27e68370cf..d917086023 100644
> --- a/src/qemu/qemu_hotplug.c
> +++ b/src/qemu/qemu_hotplug.c
> @@ -992,10 +992,9 @@ qemuDomainAttachDeviceDiskLiveInternal(virQEMUDriver *driver,
>      bool releaseSeclabel = false;
>      int ret = -1;
>  
> -    if (disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM ||
> -        disk->device == VIR_DOMAIN_DISK_DEVICE_FLOPPY) {
> +    if (disk->device == VIR_DOMAIN_DISK_DEVICE_FLOPPY) {
>          virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
> -                       _("cdrom/floppy device hotplug isn't supported"));
> +                       _("floppy device hotplug isn't supported"));
>          return -1;
>      }
>  
> @@ -1025,6 +1024,10 @@ qemuDomainAttachDeviceDiskLiveInternal(virQEMUDriver *driver,
>          break;
>  
>      case VIR_DOMAIN_DISK_BUS_VIRTIO:
> +        if (disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM) {
> +            virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
> +                       _("cdrom device with virtio bus isn't supported"));

Alignment.

> +        }
>          if (qemuDomainEnsureVirtioAddress(&releaseVirtio, vm, dev) < 0)
>              goto cleanup;
>          break;
> @@ -5414,6 +5417,10 @@ qemuDomainDetachPrepDisk(virDomainObj *vm,
>  
>      case VIR_DOMAIN_DISK_DEVICE_CDROM:
>      case VIR_DOMAIN_DISK_DEVICE_FLOPPY:
> +        if ((virDomainDiskBus) disk->bus == VIR_DOMAIN_DISK_BUS_USB ||
> +            (virDomainDiskBus) disk->bus == VIR_DOMAIN_DISK_BUS_SCSI) {

No need for typecasting here. However, this allows floppy hotunplug
which I believe is not supported on QEMU side.

> +            break;
> +        }
>          virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
>                         _("disk device type '%s' cannot be detached"),
>                         virDomainDiskDeviceTypeToString(disk->device));


I'm fixing all these minor issues before pushing.

Reviewed-by: Michal Privoznik <mprivozn at redhat.com>

Congratulations on your first libvirt contribution!

Michal