On Mon, Sep 06, 2021 at 09:33:15AM +0200, Stefano Garzarella wrote: > On Sun, Sep 05, 2021 at 04:18:52PM -0400, Michael S. Tsirkin wrote: > > On Sun, Sep 05, 2021 at 07:21:10PM +0300, Arseny Krasnov wrote: > > > > > > On 05.09.2021 19:19, Michael S. Tsirkin wrote: > > > > On Sun, Sep 05, 2021 at 07:02:44PM +0300, Arseny Krasnov wrote: > > > >> On 05.09.2021 18:55, Michael S. Tsirkin wrote: > > > >>> On Fri, Sep 03, 2021 at 03:30:13PM +0300, Arseny Krasnov wrote: > > > >>>> This patchset implements support of MSG_EOR bit for SEQPACKET > > > >>>> AF_VSOCK sockets over virtio transport. > > > >>>> First we need to define 'messages' and 'records' like this: > > > >>>> Message is result of sending calls: 'write()', 'send()', 'sendmsg()' > > > >>>> etc. It has fixed maximum length, and it bounds are visible using > > > >>>> return from receive calls: 'read()', 'recv()', 'recvmsg()' etc. > > > >>>> Current implementation based on message definition above. > > > >>>> Record has unlimited length, it consists of multiple message, > > > >>>> and bounds of record are visible via MSG_EOR flag returned from > > > >>>> 'recvmsg()' call. Sender passes MSG_EOR to sending system call and > > > >>>> receiver will see MSG_EOR when corresponding message will be processed. > > > >>>> Idea of patchset comes from POSIX: it says that SEQPACKET > > > >>>> supports record boundaries which are visible for receiver using > > > >>>> MSG_EOR bit. So, it looks like MSG_EOR is enough thing for SEQPACKET > > > >>>> and we don't need to maintain boundaries of corresponding send - > > > >>>> receive system calls. But, for 'sendXXX()' and 'recXXX()' POSIX says, > > > >>>> that all these calls operates with messages, e.g. 'sendXXX()' sends > > > >>>> message, while 'recXXX()' reads messages and for SEQPACKET, 'recXXX()' > > > >>>> must read one entire message from socket, dropping all out of size > > > >>>> bytes. Thus, both message boundaries and MSG_EOR bit must be supported > > > >>>> to follow POSIX rules. > > > >>>> To support MSG_EOR new bit was added along with existing > > > >>>> 'VIRTIO_VSOCK_SEQ_EOR': 'VIRTIO_VSOCK_SEQ_EOM'(end-of-message) - now it > > > >>>> works in the same way as 'VIRTIO_VSOCK_SEQ_EOR'. But 'VIRTIO_VSOCK_SEQ_EOR' > > > >>>> is used to mark 'MSG_EOR' bit passed from userspace. > > > >>>> This patchset includes simple test for MSG_EOR. > > > >>> I'm prepared to merge this for this window, > > > >>> but I'm not sure who's supposed to ack the net/vmw_vsock/af_vsock.c > > > >>> bits. It's a harmless variable renaming so maybe it does not matter. > > > >>> > > > >>> The rest is virtio stuff so I guess my tree is ok. > > > >>> > > > >>> Objections, anyone? > > > >> https://lkml.org/lkml/2021/9/3/76 this is v4. It is same as v5 in af_vsock.c changes. > > > >> > > > >> It has Reviewed by from Stefano Garzarella. > > > > Is Stefano the maintainer for af_vsock then? > > > > I wasn't sure. > > I'm maintaining virtio-vsock stuff, but I'm reviewing most of the af_vsock > patches. We don't have an entry for it in MAINTAINERS, maybe we should. Yea, please add that. And the test I guess? It's now Dave and while he's great as we all know, reducing the load on him is a good thing to do. > > > Ack, let's wait for maintainer's comment > > > > > > The specific patch is a trivial variable renaming so > > I parked this in my tree for now, will merge unless I > > hear any objections in the next couple of days. > > I agree, I think your tree is fine, since this series is mostly about > virtio-vsock. > > Thanks, > Stefano _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
