Using the virtqueue_avail_bytes() function had an unnecessarily crippling effect on the number of bytes needed by the guest as reported to the chardev layer in the can_read() callback.
Using the new virtqueue_get_avail_bytes() function will let us advertise the exact number of bytes we can send to the guest. Signed-off-by: Amit Shah <amit.s...@redhat.com> --- hw/virtio-serial-bus.c | 11 +++-------- 1 files changed, 3 insertions(+), 8 deletions(-) diff --git a/hw/virtio-serial-bus.c b/hw/virtio-serial-bus.c index 82073f5..d20bd8b 100644 --- a/hw/virtio-serial-bus.c +++ b/hw/virtio-serial-bus.c @@ -287,6 +287,7 @@ ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf, size_t virtio_serial_guest_ready(VirtIOSerialPort *port) { VirtQueue *vq = port->ivq; + unsigned int bytes; if (!virtio_queue_ready(vq) || !(port->vser->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK) || @@ -296,14 +297,8 @@ size_t virtio_serial_guest_ready(VirtIOSerialPort *port) if (use_multiport(port->vser) && !port->guest_connected) { return 0; } - - if (virtqueue_avail_bytes(vq, 4096, 0)) { - return 4096; - } - if (virtqueue_avail_bytes(vq, 1, 0)) { - return 1; - } - return 0; + virtqueue_get_avail_bytes(vq, &bytes, NULL); + return bytes; } static void flush_queued_data_bh(void *opaque) -- 1.7.7.6