Re: [RFC PATCH v1 0/1] virtio-vsock: introduce SEQPACKET description

[Stefano Garzarella <sgarzare@redhat.com>]

On Thu, Feb 18, 2021 at 09:07:12AM +0300, Arseny Krasnov wrote:
> This patchset adds description of SOCK_SEQPACKET socket's type
> of virtio vsock.
>
> Here is implementation:
> https://lkml.org/lkml/2021/2/18/24
>
> Arseny Krasnov(1):
>  virtio-vsock: add SOCK_SEQPACKET description
>
> virtio-vsock.tex | 40 +++++++++++++++++++++++++++++++++++++---
> 1 files changed, 37 insertions(+), 3 deletions(-)
>
> TODO:
> - for messages identification I use header's field called 'msg_cnt'.
>  May be it is better to call it 'msg_id' or 'msg_num', because it
>  is used as ID, but implemented as counter.

If we use it only as an identifier, I think 'msg_id' is preferable and 
we shouldn't mention in the specs that it's a counter, since it's just a 
possible implementation.
Instead if we use the counter for some control, for example if we lost a 
packet, then maybe msg_cnt is better.
But since the channel shouldn't lose packets, I don't think this is the 
case.

> - in current version of specification, some values of headers' fields
>  still unnamed, for example type of socket (stream or seqpacket), then
>  shutdown flags. Spec says that for stream socket value of 'type'
>  must be 1. For receive shutdown bit 0 is set in 'flags', for send
>  shutdown bit 1 is set in 'flags'. But in Linux these unnamed ones and
>  zeroes are implemented as enums, so may be it will be ok to add such
>  enums in specification (as 'enum virtio_vsock_event_id').

Since we have an enumerate for VIRTIO_VSOCK_OP_* values, I think we can 
add enums for socket type and maybe 'flags'.

Thanks,
Stefano