9P: Get rid of REQ_STATUS_FLSH

This request state is mostly useless, and properly implementing it
for RDMA would require an extra lock to be taken in handle_recv()
and in rdma_cancel() to avoid this race:

    handle_recv()           rdma_cancel()
        .                     .
        .                   if req->state == SENT
    req->state = RCVD         .
        .                           req->state = FLSH

So just get rid of it.
Signed-off-by: Simon Derr <simon.derr@bull.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

include/net/9p/client.h

@@ -67,7 +67,6 @@ enum p9_trans_status {
  * @REQ_STATUS_ALLOC: request has been allocated but not sent
  * @REQ_STATUS_UNSENT: request waiting to be sent
  * @REQ_STATUS_SENT: request sent to server
- * @REQ_STATUS_FLSH: a flush has been sent for this request
  * @REQ_STATUS_RCVD: response received from server
  * @REQ_STATUS_FLSHD: request has been flushed
  * @REQ_STATUS_ERROR: request encountered an error on the client side
@@ -83,7 +82,6 @@ enum p9_req_status_t {
 	REQ_STATUS_ALLOC,
 	REQ_STATUS_UNSENT,
 	REQ_STATUS_SENT,
-	REQ_STATUS_FLSH,
 	REQ_STATUS_RCVD,
 	REQ_STATUS_FLSHD,
 	REQ_STATUS_ERROR,

net/9p/client.c

@@ -667,7 +667,7 @@ static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 	 * if we haven't received a response for oldreq,
 	 * remove it from the list
 	 */
-	if (oldreq->status == REQ_STATUS_FLSH)
+	if (oldreq->status == REQ_STATUS_SENT)
 		if (c->trans_mod->cancelled)
 			c->trans_mod->cancelled(c, oldreq);
 

net/9p/trans_fd.c

@@ -345,8 +345,7 @@ static void p9_read_work(struct work_struct *work)
 			 "mux %p pkt: size: %d bytes tag: %d\n", m, n, tag);
 
 		m->req = p9_tag_lookup(m->client, tag);
-		if (!m->req || (m->req->status != REQ_STATUS_SENT &&
-					m->req->status != REQ_STATUS_FLSH)) {
+		if (!m->req || (m->req->status != REQ_STATUS_SENT)) {
 			p9_debug(P9_DEBUG_ERROR, "Unexpected packet tag %d\n",
 				 tag);
 			err = -EIO;
@@ -701,9 +700,7 @@ static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req)
 		list_del(&req->req_list);
 		req->status = REQ_STATUS_FLSHD;
 		ret = 0;
-	} else if (req->status == REQ_STATUS_SENT)
-		req->status = REQ_STATUS_FLSH;
-
+	}
 	spin_unlock(&client->lock);
 
 	return ret;