Re: [PATCH v6 06/25] rtrs: client: main functionality

[Bart Van Assche <bvanassche@acm.org>]

On 1/3/20 6:30 AM, Jinpu Wang wrote:
> On Tue, Dec 31, 2019 at 12:53 AM Bart Van Assche <bvanassche@acm.org> wrote:
>> On 2019-12-30 02:29, Jack Wang wrote:
>>> +static void complete_rdma_req(struct rtrs_clt_io_req *req, int errno,
>>> +                           bool notify, bool can_wait)
>>> +{
>>> +     struct rtrs_clt_con *con = req->con;
>>> +     struct rtrs_clt_sess *sess;
>>> +     int err;
>>> +
>>> +     if (WARN_ON(!req->in_use))
>>> +             return;
>>> +     if (WARN_ON(!req->con))
>>> +             return;
>>> +     sess = to_clt_sess(con->c.sess);
>>> +
>>> +     if (req->sg_cnt) {
>>> +             if (unlikely(req->dir == DMA_FROM_DEVICE && req->need_inv)) {
>>> +                     /*
>>> +                      * We are here to invalidate RDMA read requests
>>> +                      * ourselves.  In normal scenario server should
>>> +                      * send INV for all requested RDMA reads, but
>>> +                      * we are here, thus two things could happen:
>>> +                      *
>>> +                      *    1.  this is failover, when errno != 0
>>> +                      *        and can_wait == 1,
>>> +                      *
>>> +                      *    2.  something totally bad happened and
>>> +                      *        server forgot to send INV, so we
>>> +                      *        should do that ourselves.
>>> +                      */
>>
>> Please document in the protocol documentation when RDMA reads are used.
> We don't use RDMA READ, it's requested RDMA read meaning, server side will do
> RDMA write to the buffers.

Please make the comment more clear. The comment says "RDMA read" twice.

Thanks,

Bart.