On Tue, Jul 08, 2025 at 02:36:11PM +0800, Xuewei Niu wrote: > From: Dexuan Cui <decui@xxxxxxxxxxxxx> > > When hv_sock was originally added, __vsock_stream_recvmsg() and > vsock_stream_has_data() actually only needed to know whether there > is any readable data or not, so hvs_stream_has_data() was written to > return 1 or 0 for simplicity. > > However, now hvs_stream_has_data() should return the readable bytes > because vsock_data_ready() -> vsock_stream_has_data() needs to know the > actual bytes rather than a boolean value of 1 or 0. > > The SIOCINQ ioctl support also needs hvs_stream_has_data() to return > the readable bytes. > > Let hvs_stream_has_data() return the readable bytes of the payload in > the next host-to-guest VMBus hv_sock packet. > > Note: there may be multiple incoming hv_sock packets pending in the > VMBus channel's ringbuffer, but so far there is not a VMBus API that > allows us to know all the readable bytes in total without reading and > caching the payload of the multiple packets, so let's just return the > readable bytes of the next single packet. In the future, we'll either > add a VMBus API that allows us to know the total readable bytes without > touching the data in the ringbuffer, or the hv_sock driver needs to > understand the VMBus packet format and parse the packets directly. > > Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> > Signed-off-by: Xuewei Niu <niuxuewei.nxw@xxxxxxxxxxxx> Acked-by: Wei Liu <wei.liu@xxxxxxxxxx>
