Hans de Goede <hdego...@redhat.com> writes:
> Most frontends can't really determine if the guest actually has the frontend
> side open. So lets automatically generate fe_open / fe_close as soon as a
> frontend becomes ready (as signalled by calling qemu_chr_add_handlers) /
> becomes non ready (as signalled by setting all handlers to NULL).
>
> And allow frontends which can actually determine if the guest is listening to
> opt-out of this.
Could we change virtio-serial to delay calling add_handlers so that we
could not introduce this variable?
Regards,
Anthony Liguori
>
> Signed-off-by: Hans de Goede <hdego...@redhat.com>
> ---
> hw/usb/redirect.c | 2 --
> hw/virtio-console.c | 1 +
> include/char/char.h | 1 +
> qemu-char.c | 13 +++++++++++++
> 4 files changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
> index 4d565ba..0ddb081 100644
> --- a/hw/usb/redirect.c
> +++ b/hw/usb/redirect.c
> @@ -1310,7 +1310,6 @@ static int usbredir_initfn(USBDevice *udev)
> dev->compatible_speedmask = USB_SPEED_MASK_FULL | USB_SPEED_MASK_HIGH;
>
> /* Let the backend know we are ready */
> - qemu_chr_fe_open(dev->cs);
> qemu_chr_add_handlers(dev->cs, usbredir_chardev_can_read,
> usbredir_chardev_read, usbredir_chardev_event,
> dev);
>
> @@ -1334,7 +1333,6 @@ static void usbredir_handle_destroy(USBDevice *udev)
> {
> USBRedirDevice *dev = DO_UPCAST(USBRedirDevice, dev, udev);
>
> - qemu_chr_fe_close(dev->cs);
> qemu_chr_delete(dev->cs);
> /* Note must be done after qemu_chr_close, as that causes a close event
> */
> qemu_bh_delete(dev->chardev_close_bh);
> diff --git a/hw/virtio-console.c b/hw/virtio-console.c
> index 8ef76e2..209ea38 100644
> --- a/hw/virtio-console.c
> +++ b/hw/virtio-console.c
> @@ -140,6 +140,7 @@ static int virtconsole_initfn(VirtIOSerialPort *port)
> }
>
> if (vcon->chr) {
> + vcon->chr->explicit_fe_open = 1;
> qemu_chr_add_handlers(vcon->chr, chr_can_read, chr_read, chr_event,
> vcon);
> }
> diff --git a/include/char/char.h b/include/char/char.h
> index 3174575..27ebbc3 100644
> --- a/include/char/char.h
> +++ b/include/char/char.h
> @@ -76,6 +76,7 @@ struct CharDriverState {
> char *filename;
> int be_open;
> int fe_open;
> + int explicit_fe_open;
> int avail_connections;
> QemuOpts *opts;
> QTAILQ_ENTRY(CharDriverState) next;
> diff --git a/qemu-char.c b/qemu-char.c
> index 554d72f..7c57971 100644
> --- a/qemu-char.c
> +++ b/qemu-char.c
> @@ -194,9 +194,14 @@ void qemu_chr_add_handlers(CharDriverState *s,
> IOEventHandler *fd_event,
> void *opaque)
> {
> + int fe_open;
> +
> if (!opaque && !fd_can_read && !fd_read && !fd_event) {
> /* chr driver being released. */
> + fe_open = 0;
> ++s->avail_connections;
> + } else {
> + fe_open = 1;
> }
> s->chr_can_read = fd_can_read;
> s->chr_read = fd_read;
> @@ -205,6 +210,14 @@ void qemu_chr_add_handlers(CharDriverState *s,
> if (s->chr_update_read_handler)
> s->chr_update_read_handler(s);
>
> + if (!s->explicit_fe_open) {
> + if (fe_open) {
> + qemu_chr_fe_open(s);
> + } else {
> + qemu_chr_fe_close(s);
> + }
> + }
> +
> /* We're connecting to an already opened device, so let's make sure we
> also get the open event */
> if (s->be_open) {
> --
> 1.8.1.4
