SUNRPC: Add socket transmit queue offset tracking

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

include/linux/sunrpc/xprtsock.h

@@ -42,6 +42,13 @@ struct sock_xprt {
 				flags;
 	} recv;
 
+	/*
+	 * State of TCP transmit queue
+	 */
+	struct {
+		u32		offset;
+	} xmit;
+
 	/*
 	 * Connection of transports
 	 */

net/sunrpc/xprtsock.c

@@ -461,7 +461,7 @@ static int xs_nospace(struct rpc_task *task)
 	int ret = -EAGAIN;
 
 	dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
-			task->tk_pid, req->rq_slen - req->rq_bytes_sent,
+			task->tk_pid, req->rq_slen - transport->xmit.offset,
 			req->rq_slen);
 
 	/* Protect against races with write_space */
@@ -528,19 +528,22 @@ static int xs_local_send_request(struct rpc_task *task)
 			req->rq_svec->iov_base, req->rq_svec->iov_len);
 
 	req->rq_xtime = ktime_get();
-	status = xs_sendpages(transport->sock, NULL, 0, xdr, req->rq_bytes_sent,
+	status = xs_sendpages(transport->sock, NULL, 0, xdr,
+			      transport->xmit.offset,
 			      true, &sent);
 	dprintk("RPC:       %s(%u) = %d\n",
-			__func__, xdr->len - req->rq_bytes_sent, status);
+			__func__, xdr->len - transport->xmit.offset, status);
 
 	if (status == -EAGAIN && sock_writeable(transport->inet))
 		status = -ENOBUFS;
 
 	if (likely(sent > 0) || status == 0) {
-		req->rq_bytes_sent += sent;
-		req->rq_xmit_bytes_sent += sent;
+		transport->xmit.offset += sent;
+		req->rq_bytes_sent = transport->xmit.offset;
 		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
+			req->rq_xmit_bytes_sent += transport->xmit.offset;
 			req->rq_bytes_sent = 0;
+			transport->xmit.offset = 0;
 			return 0;
 		}
 		status = -EAGAIN;
@@ -592,10 +595,10 @@ static int xs_udp_send_request(struct rpc_task *task)
 		return -ENOTCONN;
 	req->rq_xtime = ktime_get();
 	status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
-			      xdr, req->rq_bytes_sent, true, &sent);
+			      xdr, 0, true, &sent);
 
 	dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
-			xdr->len - req->rq_bytes_sent, status);
+			xdr->len, status);
 
 	/* firewall is blocking us, don't return -EAGAIN or we end up looping */
 	if (status == -EPERM)
@@ -684,17 +687,20 @@ static int xs_tcp_send_request(struct rpc_task *task)
 	while (1) {
 		sent = 0;
 		status = xs_sendpages(transport->sock, NULL, 0, xdr,
-				      req->rq_bytes_sent, zerocopy, &sent);
+				      transport->xmit.offset,
+				      zerocopy, &sent);
 
 		dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
-				xdr->len - req->rq_bytes_sent, status);
+				xdr->len - transport->xmit.offset, status);
 
 		/* If we've sent the entire packet, immediately
 		 * reset the count of bytes sent. */
-		req->rq_bytes_sent += sent;
-		req->rq_xmit_bytes_sent += sent;
+		transport->xmit.offset += sent;
+		req->rq_bytes_sent = transport->xmit.offset;
 		if (likely(req->rq_bytes_sent >= req->rq_slen)) {
+			req->rq_xmit_bytes_sent += transport->xmit.offset;
 			req->rq_bytes_sent = 0;
+			transport->xmit.offset = 0;
 			return 0;
 		}
 
@@ -760,18 +766,13 @@ static int xs_tcp_send_request(struct rpc_task *task)
  */
 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 {
-	struct rpc_rqst *req;
+	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 
 	if (task != xprt->snd_task)
 		return;
 	if (task == NULL)
 		goto out_release;
-	req = task->tk_rqstp;
-	if (req == NULL)
-		goto out_release;
-	if (req->rq_bytes_sent == 0)
-		goto out_release;
-	if (req->rq_bytes_sent == req->rq_snd_buf.len)
+	if (transport->xmit.offset == 0 || !xprt_connected(xprt))
 		goto out_release;
 	set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 out_release:
@@ -2021,6 +2022,8 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,
 		write_unlock_bh(&sk->sk_callback_lock);
 	}
 
+	transport->xmit.offset = 0;
+
 	/* Tell the socket layer to start connecting... */
 	xprt->stat.connect_count++;
 	xprt->stat.connect_start = jiffies;
@@ -2384,6 +2387,7 @@ static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
 	transport->recv.len = 0;
 	transport->recv.copied = 0;
 	transport->recv.flags = TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
+	transport->xmit.offset = 0;
 
 	/* Tell the socket layer to start connecting... */
 	xprt->stat.connect_count++;