@@ -20,11 +20,11 @@ typedef struct VirtConsole {
/* Callback function that's called when the guest sends us data */
-static void flush_buf(VirtIOSerialPort *port, const uint8_t *buf, size_t len)
+static ssize_t flush_buf(VirtIOSerialPort *port, const uint8_t *buf, size_t len)
{
VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
- qemu_chr_write(vcon->chr, buf, len);
+ return qemu_chr_write(vcon->chr, buf, len);
}
/* Readiness of the guest to accept data on a port */
@@ -137,10 +137,11 @@ struct VirtIOSerialPortInfo {
/*
* Guest wrote some data to the port. This data is handed over to
- * the app via this callback. The app is supposed to consume all
- * the data that is presented to it.
+ * the app via this callback. The app can return a size less than
+ * 'len'. In this case, throttling will be enabled for this port.
*/
- void (*have_data)(VirtIOSerialPort *port, const uint8_t *buf, size_t len);
+ ssize_t (*have_data)(VirtIOSerialPort *port, const uint8_t *buf,
+ size_t len);
};
/* Interface to the virtio-serial bus */
The have_data() API to hand off guest data to apps using virtio-serial so far assumed all the data was consumed. Relax this assumption. Future commits will allow for incomplete writes. Signed-off-by: Amit Shah <amit.shah@redhat.com> --- hw/virtio-console.c | 4 ++-- hw/virtio-serial.h | 7 ++++--- 2 files changed, 6 insertions(+), 5 deletions(-)