SUNRPC: Fixup v4.1 backchannel request timeouts

After commit 59464b26 ("SUNRPC: SOFTCONN tasks should time out when on
the sending list"), any 4.1 backchannel tasks placed on the sending queue
would immediately return with -ETIMEDOUT since their req timers are zero.

Initialize the backchannel's rpc_rqst timeout parameters from the xprt's
default timeout settings.

Fixes: 59464b26 ("SUNRPC: SOFTCONN tasks should time out when on the sending list")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

net/sunrpc/xprt.c

@@ -651,9 +651,9 @@ static unsigned long xprt_abs_ktime_to_jiffies(ktime_t abstime)
 		jiffies + nsecs_to_jiffies(-delta);
 }
 
-static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req)
+static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req,
+		const struct rpc_timeout *to)
 {
-	const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
 	unsigned long majortimeo = req->rq_timeout;
 
 	if (to->to_exponential)
@@ -665,9 +665,10 @@ static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req)
 	return majortimeo;
 }
 
-static void xprt_reset_majortimeo(struct rpc_rqst *req)
+static void xprt_reset_majortimeo(struct rpc_rqst *req,
+		const struct rpc_timeout *to)
 {
-	req->rq_majortimeo += xprt_calc_majortimeo(req);
+	req->rq_majortimeo += xprt_calc_majortimeo(req, to);
 }
 
 static void xprt_reset_minortimeo(struct rpc_rqst *req)
@@ -675,7 +676,8 @@ static void xprt_reset_minortimeo(struct rpc_rqst *req)
 	req->rq_minortimeo += req->rq_timeout;
 }
 
-static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req)
+static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req,
+		const struct rpc_timeout *to)
 {
 	unsigned long time_init;
 	struct rpc_xprt *xprt = req->rq_xprt;
@@ -684,8 +686,9 @@ static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req)
 		time_init = jiffies;
 	else
 		time_init = xprt_abs_ktime_to_jiffies(task->tk_start);
-	req->rq_timeout = task->tk_client->cl_timeout->to_initval;
-	req->rq_majortimeo = time_init + xprt_calc_majortimeo(req);
+
+	req->rq_timeout = to->to_initval;
+	req->rq_majortimeo = time_init + xprt_calc_majortimeo(req, to);
 	req->rq_minortimeo = time_init + req->rq_timeout;
 }
 
@@ -713,7 +716,7 @@ int xprt_adjust_timeout(struct rpc_rqst *req)
 	} else {
 		req->rq_timeout = to->to_initval;
 		req->rq_retries = 0;
-		xprt_reset_majortimeo(req);
+		xprt_reset_majortimeo(req, to);
 		/* Reset the RTT counters == "slow start" */
 		spin_lock(&xprt->transport_lock);
 		rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
@@ -1886,7 +1889,7 @@ xprt_request_init(struct rpc_task *task)
 	req->rq_snd_buf.bvec = NULL;
 	req->rq_rcv_buf.bvec = NULL;
 	req->rq_release_snd_buf = NULL;
-	xprt_init_majortimeo(task, req);
+	xprt_init_majortimeo(task, req, task->tk_client->cl_timeout);
 
 	trace_xprt_reserve(req);
 }
@@ -1996,6 +1999,8 @@ xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task)
 	 */
 	xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
 		xbufp->tail[0].iov_len;
+
+	xprt_init_majortimeo(task, req, req->rq_xprt->timeout);
 }
 #endif