Re: [Qemu-devel] [PATCH v4 11/13] virtio-console: chardev hotswap support

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

Hi

Looks good, but please write something in the commit message about what needs to be done for be-change (what this patch does).

thanks

----- Original Message -----
> Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> CC: Amit Shah <amit@kernel.org>
> ---
>  hw/char/virtio-console.c | 35 ++++++++++++++++++++++++++++++-----
>  1 file changed, 30 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/char/virtio-console.c b/hw/char/virtio-console.c
> index afb4949..198b2a8 100644
> --- a/hw/char/virtio-console.c
> +++ b/hw/char/virtio-console.c
> @@ -49,7 +49,7 @@ static ssize_t flush_buf(VirtIOSerialPort *port,
>      VirtConsole *vcon = VIRTIO_CONSOLE(port);
>      ssize_t ret;
>  
> -    if (!qemu_chr_fe_get_driver(&vcon->chr)) {
> +    if (!qemu_chr_fe_backend_connected(&vcon->chr)) {
>          /* If there's no backend, we can just say we consumed all data. */
>          return len;
>      }
> @@ -163,12 +163,35 @@ static void chr_event(void *opaque, int event)
>      }
>  }
>  
> +static int chr_be_change(void *opaque)
> +{
> +    VirtConsole *vcon = opaque;
> +    VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(vcon);
> +    VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);
> +
> +    if (k->is_console) {
> +        qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
> +                                 NULL, chr_be_change, vcon, NULL, true);
> +    } else {
> +        qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
> +                                 chr_event, chr_be_change, vcon, NULL,
> false);
> +    }
> +
> +    if (vcon->watch) {
> +        g_source_remove(vcon->watch);
> +        vcon->watch = qemu_chr_fe_add_watch(&vcon->chr,
> +                                            G_IO_OUT | G_IO_HUP,
> +                                            chr_write_unblocked, vcon);
> +    }
> +
> +    return 0;
> +}
> +
>  static void virtconsole_realize(DeviceState *dev, Error **errp)
>  {
>      VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(dev);
>      VirtConsole *vcon = VIRTIO_CONSOLE(dev);
>      VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(dev);
> -    Chardev *chr = qemu_chr_fe_get_driver(&vcon->chr);
>  
>      if (port->id == 0 && !k->is_console) {
>          error_setg(errp, "Port number 0 on virtio-serial devices reserved "
> @@ -176,7 +199,7 @@ static void virtconsole_realize(DeviceState *dev, Error
> **errp)
>          return;
>      }
>  
> -    if (chr) {
> +    if (qemu_chr_fe_backend_connected(&vcon->chr)) {
>          /*
>           * For consoles we don't block guest data transfer just
>           * because nothing is connected - we'll just let it go
> @@ -188,11 +211,13 @@ static void virtconsole_realize(DeviceState *dev, Error
> **errp)
>           */
>          if (k->is_console) {
>              qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
> -                                     NULL, NULL, vcon, NULL, true);
> +                                     NULL, chr_be_change,
> +                                     vcon, NULL, true);
>              virtio_serial_open(port);
>          } else {
>              qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
> -                                     chr_event, NULL, vcon, NULL, false);
> +                                     chr_event, chr_be_change,
> +                                     vcon, NULL, false);
>          }
>      }
>  }
> --
> 2.7.4
> 
>