From e300ac275bbf19b31cf5968b8de8abe52c26e163 Mon Sep 17 00:00:00 2001 From: Amit Shah Date: Mon, 13 Dec 2010 17:50:07 +0530 Subject: [PATCH] virtio-serial: Let virtio-serial-bus know if all data was consumed 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 --- hw/virtio-console.c | 4 ++-- hw/virtio-serial.h | 7 ++++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/hw/virtio-console.c b/hw/virtio-console.c index d0b935491d..62624ec780 100644 --- a/hw/virtio-console.c +++ b/hw/virtio-console.c @@ -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 */ diff --git a/hw/virtio-serial.h b/hw/virtio-serial.h index ff08c40681..9cc0fb3543 100644 --- a/hw/virtio-serial.h +++ b/hw/virtio-serial.h @@ -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 */