2 * linux/net/sunrpc/xprt.c
4 * This is a generic RPC call interface supporting congestion avoidance,
5 * and asynchronous calls.
7 * The interface works like this:
9 * - When a process places a call, it allocates a request slot if
10 * one is available. Otherwise, it sleeps on the backlog queue
12 * - Next, the caller puts together the RPC message, stuffs it into
13 * the request struct, and calls xprt_call().
14 * - xprt_call transmits the message and installs the caller on the
15 * socket's wait list. At the same time, it installs a timer that
16 * is run after the packet's timeout has expired.
17 * - When a packet arrives, the data_ready handler walks the list of
18 * pending requests for that socket. If a matching XID is found, the
19 * caller is woken up, and the timer removed.
20 * - When no reply arrives within the timeout interval, the timer is
21 * fired by the kernel and runs xprt_timer(). It either adjusts the
22 * timeout values (minor timeout) or wakes up the caller with a status
24 * - When the caller receives a notification from RPC that a reply arrived,
25 * it should release the RPC slot, and process the reply.
26 * If the call timed out, it may choose to retry the operation by
27 * adjusting the initial timeout value, and simply calling rpc_call
30 * Support for async RPC is done through a set of RPC-specific scheduling
31 * primitives that `transparently' work for processes as well as async
32 * tasks that rely on callbacks.
34 * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de>
37 #include <linux/module.h>
39 #include <linux/types.h>
40 #include <linux/interrupt.h>
41 #include <linux/workqueue.h>
42 #include <linux/random.h>
44 #include <linux/sunrpc/clnt.h>
51 # undef RPC_DEBUG_DATA
52 # define RPCDBG_FACILITY RPCDBG_XPRT
55 #define XPRT_MAX_BACKOFF (8)
60 static void xprt_request_init(struct rpc_task
*, struct rpc_xprt
*);
61 static inline void do_xprt_reserve(struct rpc_task
*);
62 static void xprt_connect_status(struct rpc_task
*task
);
63 static int __xprt_get_cong(struct rpc_xprt
*, struct rpc_task
*);
65 static int xprt_clear_backlog(struct rpc_xprt
*xprt
);
68 * Serialize write access to sockets, in order to prevent different
69 * requests from interfering with each other.
70 * Also prevents TCP socket connects from colliding with writes.
73 __xprt_lock_write(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
75 struct rpc_rqst
*req
= task
->tk_rqstp
;
77 if (test_and_set_bit(XPRT_LOCKED
, &xprt
->sockstate
)) {
78 if (task
== xprt
->snd_task
)
82 if (xprt
->nocong
|| __xprt_get_cong(xprt
, task
)) {
83 xprt
->snd_task
= task
;
85 req
->rq_bytes_sent
= 0;
90 smp_mb__before_clear_bit();
91 clear_bit(XPRT_LOCKED
, &xprt
->sockstate
);
92 smp_mb__after_clear_bit();
94 dprintk("RPC: %4d failed to lock socket %p\n", task
->tk_pid
, xprt
);
96 task
->tk_status
= -EAGAIN
;
97 if (req
&& req
->rq_ntrans
)
98 rpc_sleep_on(&xprt
->resend
, task
, NULL
, NULL
);
100 rpc_sleep_on(&xprt
->sending
, task
, NULL
, NULL
);
105 xprt_lock_write(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
109 spin_lock_bh(&xprt
->transport_lock
);
110 retval
= __xprt_lock_write(xprt
, task
);
111 spin_unlock_bh(&xprt
->transport_lock
);
117 __xprt_lock_write_next(struct rpc_xprt
*xprt
)
119 struct rpc_task
*task
;
121 if (test_and_set_bit(XPRT_LOCKED
, &xprt
->sockstate
))
123 if (!xprt
->nocong
&& RPCXPRT_CONGESTED(xprt
))
125 task
= rpc_wake_up_next(&xprt
->resend
);
127 task
= rpc_wake_up_next(&xprt
->sending
);
131 if (xprt
->nocong
|| __xprt_get_cong(xprt
, task
)) {
132 struct rpc_rqst
*req
= task
->tk_rqstp
;
133 xprt
->snd_task
= task
;
135 req
->rq_bytes_sent
= 0;
141 smp_mb__before_clear_bit();
142 clear_bit(XPRT_LOCKED
, &xprt
->sockstate
);
143 smp_mb__after_clear_bit();
147 * Releases the socket for use by other requests.
150 __xprt_release_write(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
152 if (xprt
->snd_task
== task
) {
153 xprt
->snd_task
= NULL
;
154 smp_mb__before_clear_bit();
155 clear_bit(XPRT_LOCKED
, &xprt
->sockstate
);
156 smp_mb__after_clear_bit();
157 __xprt_lock_write_next(xprt
);
162 xprt_release_write(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
164 spin_lock_bh(&xprt
->transport_lock
);
165 __xprt_release_write(xprt
, task
);
166 spin_unlock_bh(&xprt
->transport_lock
);
170 * Van Jacobson congestion avoidance. Check if the congestion window
171 * overflowed. Put the task to sleep if this is the case.
174 __xprt_get_cong(struct rpc_xprt
*xprt
, struct rpc_task
*task
)
176 struct rpc_rqst
*req
= task
->tk_rqstp
;
180 dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n",
181 task
->tk_pid
, xprt
->cong
, xprt
->cwnd
);
182 if (RPCXPRT_CONGESTED(xprt
))
185 xprt
->cong
+= RPC_CWNDSCALE
;
190 * Adjust the congestion window, and wake up the next task
191 * that has been sleeping due to congestion
194 __xprt_put_cong(struct rpc_xprt
*xprt
, struct rpc_rqst
*req
)
199 xprt
->cong
-= RPC_CWNDSCALE
;
200 __xprt_lock_write_next(xprt
);
204 * Adjust RPC congestion window
205 * We use a time-smoothed congestion estimator to avoid heavy oscillation.
208 xprt_adjust_cwnd(struct rpc_xprt
*xprt
, int result
)
213 if (result
>= 0 && cwnd
<= xprt
->cong
) {
214 /* The (cwnd >> 1) term makes sure
215 * the result gets rounded properly. */
216 cwnd
+= (RPC_CWNDSCALE
* RPC_CWNDSCALE
+ (cwnd
>> 1)) / cwnd
;
217 if (cwnd
> RPC_MAXCWND(xprt
))
218 cwnd
= RPC_MAXCWND(xprt
);
219 __xprt_lock_write_next(xprt
);
220 } else if (result
== -ETIMEDOUT
) {
222 if (cwnd
< RPC_CWNDSCALE
)
223 cwnd
= RPC_CWNDSCALE
;
225 dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n",
226 xprt
->cong
, xprt
->cwnd
, cwnd
);
230 static void xprt_reset_majortimeo(struct rpc_rqst
*req
)
232 struct rpc_timeout
*to
= &req
->rq_xprt
->timeout
;
234 req
->rq_majortimeo
= req
->rq_timeout
;
235 if (to
->to_exponential
)
236 req
->rq_majortimeo
<<= to
->to_retries
;
238 req
->rq_majortimeo
+= to
->to_increment
* to
->to_retries
;
239 if (req
->rq_majortimeo
> to
->to_maxval
|| req
->rq_majortimeo
== 0)
240 req
->rq_majortimeo
= to
->to_maxval
;
241 req
->rq_majortimeo
+= jiffies
;
245 * xprt_adjust_timeout - adjust timeout values for next retransmit
246 * @req: RPC request containing parameters to use for the adjustment
249 int xprt_adjust_timeout(struct rpc_rqst
*req
)
251 struct rpc_xprt
*xprt
= req
->rq_xprt
;
252 struct rpc_timeout
*to
= &xprt
->timeout
;
255 if (time_before(jiffies
, req
->rq_majortimeo
)) {
256 if (to
->to_exponential
)
257 req
->rq_timeout
<<= 1;
259 req
->rq_timeout
+= to
->to_increment
;
260 if (to
->to_maxval
&& req
->rq_timeout
>= to
->to_maxval
)
261 req
->rq_timeout
= to
->to_maxval
;
263 pprintk("RPC: %lu retrans\n", jiffies
);
265 req
->rq_timeout
= to
->to_initval
;
267 xprt_reset_majortimeo(req
);
268 /* Reset the RTT counters == "slow start" */
269 spin_lock_bh(&xprt
->transport_lock
);
270 rpc_init_rtt(req
->rq_task
->tk_client
->cl_rtt
, to
->to_initval
);
271 spin_unlock_bh(&xprt
->transport_lock
);
272 pprintk("RPC: %lu timeout\n", jiffies
);
276 if (req
->rq_timeout
== 0) {
277 printk(KERN_WARNING
"xprt_adjust_timeout: rq_timeout = 0!\n");
278 req
->rq_timeout
= 5 * HZ
;
284 xprt_socket_autoclose(void *args
)
286 struct rpc_xprt
*xprt
= (struct rpc_xprt
*)args
;
288 xprt_disconnect(xprt
);
289 xprt
->ops
->close(xprt
);
290 xprt_release_write(xprt
, NULL
);
294 * xprt_disconnect - mark a transport as disconnected
295 * @xprt: transport to flag for disconnect
298 void xprt_disconnect(struct rpc_xprt
*xprt
)
300 dprintk("RPC: disconnected transport %p\n", xprt
);
301 spin_lock_bh(&xprt
->transport_lock
);
302 xprt_clear_connected(xprt
);
303 rpc_wake_up_status(&xprt
->pending
, -ENOTCONN
);
304 spin_unlock_bh(&xprt
->transport_lock
);
308 xprt_init_autodisconnect(unsigned long data
)
310 struct rpc_xprt
*xprt
= (struct rpc_xprt
*)data
;
312 spin_lock(&xprt
->transport_lock
);
313 if (!list_empty(&xprt
->recv
) || xprt
->shutdown
)
315 if (test_and_set_bit(XPRT_LOCKED
, &xprt
->sockstate
))
317 spin_unlock(&xprt
->transport_lock
);
318 /* Let keventd close the socket */
319 if (test_bit(XPRT_CONNECTING
, &xprt
->sockstate
) != 0)
320 xprt_release_write(xprt
, NULL
);
322 schedule_work(&xprt
->task_cleanup
);
325 spin_unlock(&xprt
->transport_lock
);
329 * xprt_connect - schedule a transport connect operation
330 * @task: RPC task that is requesting the connect
333 void xprt_connect(struct rpc_task
*task
)
335 struct rpc_xprt
*xprt
= task
->tk_xprt
;
337 dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task
->tk_pid
,
338 xprt
, (xprt_connected(xprt
) ? "is" : "is not"));
340 if (xprt
->shutdown
) {
341 task
->tk_status
= -EIO
;
344 if (!xprt
->addr
.sin_port
) {
345 task
->tk_status
= -EIO
;
348 if (!xprt_lock_write(xprt
, task
))
350 if (xprt_connected(xprt
))
351 xprt_release_write(xprt
, task
);
354 task
->tk_rqstp
->rq_bytes_sent
= 0;
356 task
->tk_timeout
= RPC_CONNECT_TIMEOUT
;
357 rpc_sleep_on(&xprt
->pending
, task
, xprt_connect_status
, NULL
);
358 xprt
->ops
->connect(task
);
363 static void xprt_connect_status(struct rpc_task
*task
)
365 struct rpc_xprt
*xprt
= task
->tk_xprt
;
367 if (task
->tk_status
>= 0) {
368 dprintk("RPC: %4d xprt_connect_status: connection established\n",
373 switch (task
->tk_status
) {
376 dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n",
377 task
->tk_pid
, task
->tk_client
->cl_server
);
380 dprintk("RPC: %4d xprt_connect_status: connection broken\n",
384 dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n",
388 dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n",
389 task
->tk_pid
, -task
->tk_status
, task
->tk_client
->cl_server
);
390 xprt_release_write(xprt
, task
);
391 task
->tk_status
= -EIO
;
395 /* if soft mounted, just cause this RPC to fail */
396 if (RPC_IS_SOFT(task
)) {
397 xprt_release_write(xprt
, task
);
398 task
->tk_status
= -EIO
;
403 * xprt_lookup_rqst - find an RPC request corresponding to an XID
404 * @xprt: transport on which the original request was transmitted
405 * @xid: RPC XID of incoming reply
408 struct rpc_rqst
*xprt_lookup_rqst(struct rpc_xprt
*xprt
, u32 xid
)
410 struct list_head
*pos
;
411 struct rpc_rqst
*req
= NULL
;
413 list_for_each(pos
, &xprt
->recv
) {
414 struct rpc_rqst
*entry
= list_entry(pos
, struct rpc_rqst
, rq_list
);
415 if (entry
->rq_xid
== xid
) {
424 * xprt_complete_rqst - called when reply processing is complete
425 * @xprt: controlling transport
426 * @req: RPC request that just completed
427 * @copied: actual number of bytes received from the transport
430 void xprt_complete_rqst(struct rpc_xprt
*xprt
, struct rpc_rqst
*req
, int copied
)
432 struct rpc_task
*task
= req
->rq_task
;
433 struct rpc_clnt
*clnt
= task
->tk_client
;
435 /* Adjust congestion window */
437 unsigned timer
= task
->tk_msg
.rpc_proc
->p_timer
;
438 xprt_adjust_cwnd(xprt
, copied
);
439 __xprt_put_cong(xprt
, req
);
441 if (req
->rq_ntrans
== 1)
442 rpc_update_rtt(clnt
->cl_rtt
, timer
,
443 (long)jiffies
- req
->rq_xtime
);
444 rpc_set_timeo(clnt
->cl_rtt
, timer
, req
->rq_ntrans
- 1);
449 /* Profile only reads for now */
451 static unsigned long nextstat
;
452 static unsigned long pkt_rtt
, pkt_len
, pkt_cnt
;
455 pkt_len
+= req
->rq_slen
+ copied
;
456 pkt_rtt
+= jiffies
- req
->rq_xtime
;
457 if (time_before(nextstat
, jiffies
)) {
458 printk("RPC: %lu %ld cwnd\n", jiffies
, xprt
->cwnd
);
459 printk("RPC: %ld %ld %ld %ld stat\n",
460 jiffies
, pkt_cnt
, pkt_len
, pkt_rtt
);
461 pkt_rtt
= pkt_len
= pkt_cnt
= 0;
462 nextstat
= jiffies
+ 5 * HZ
;
467 dprintk("RPC: %4d has input (%d bytes)\n", task
->tk_pid
, copied
);
468 list_del_init(&req
->rq_list
);
469 req
->rq_received
= req
->rq_private_buf
.len
= copied
;
471 /* ... and wake up the process. */
472 rpc_wake_up_task(task
);
477 * RPC receive timeout handler.
480 xprt_timer(struct rpc_task
*task
)
482 struct rpc_rqst
*req
= task
->tk_rqstp
;
483 struct rpc_xprt
*xprt
= req
->rq_xprt
;
485 spin_lock(&xprt
->transport_lock
);
486 if (req
->rq_received
)
489 xprt_adjust_cwnd(req
->rq_xprt
, -ETIMEDOUT
);
490 __xprt_put_cong(xprt
, req
);
492 dprintk("RPC: %4d xprt_timer (%s request)\n",
493 task
->tk_pid
, req
? "pending" : "backlogged");
495 task
->tk_status
= -ETIMEDOUT
;
497 task
->tk_timeout
= 0;
498 rpc_wake_up_task(task
);
499 spin_unlock(&xprt
->transport_lock
);
503 * xprt_prepare_transmit - reserve the transport before sending a request
504 * @task: RPC task about to send a request
507 int xprt_prepare_transmit(struct rpc_task
*task
)
509 struct rpc_rqst
*req
= task
->tk_rqstp
;
510 struct rpc_xprt
*xprt
= req
->rq_xprt
;
513 dprintk("RPC: %4d xprt_prepare_transmit\n", task
->tk_pid
);
518 spin_lock_bh(&xprt
->transport_lock
);
519 if (req
->rq_received
&& !req
->rq_bytes_sent
) {
520 err
= req
->rq_received
;
523 if (!__xprt_lock_write(xprt
, task
)) {
528 if (!xprt_connected(xprt
)) {
533 spin_unlock_bh(&xprt
->transport_lock
);
538 * xprt_transmit - send an RPC request on a transport
539 * @task: controlling RPC task
541 * We have to copy the iovec because sendmsg fiddles with its contents.
543 void xprt_transmit(struct rpc_task
*task
)
545 struct rpc_clnt
*clnt
= task
->tk_client
;
546 struct rpc_rqst
*req
= task
->tk_rqstp
;
547 struct rpc_xprt
*xprt
= req
->rq_xprt
;
550 dprintk("RPC: %4d xprt_transmit(%u)\n", task
->tk_pid
, req
->rq_slen
);
553 if (!req
->rq_received
) {
554 if (list_empty(&req
->rq_list
)) {
555 spin_lock_bh(&xprt
->transport_lock
);
556 /* Update the softirq receive buffer */
557 memcpy(&req
->rq_private_buf
, &req
->rq_rcv_buf
,
558 sizeof(req
->rq_private_buf
));
559 /* Add request to the receive list */
560 list_add_tail(&req
->rq_list
, &xprt
->recv
);
561 spin_unlock_bh(&xprt
->transport_lock
);
562 xprt_reset_majortimeo(req
);
563 /* Turn off autodisconnect */
564 del_singleshot_timer_sync(&xprt
->timer
);
566 } else if (!req
->rq_bytes_sent
)
569 status
= xprt
->ops
->send_request(task
);
573 /* Note: at this point, task->tk_sleeping has not yet been set,
574 * hence there is no danger of the waking up task being put on
575 * schedq, and being picked up by a parallel run of rpciod().
577 task
->tk_status
= status
;
581 task
->tk_timeout
= RPC_REESTABLISH_TIMEOUT
;
582 rpc_sleep_on(&xprt
->sending
, task
, NULL
, NULL
);
588 xprt_disconnect(xprt
);
590 xprt_release_write(xprt
, task
);
593 dprintk("RPC: %4d xmit complete\n", task
->tk_pid
);
594 /* Set the task's receive timeout value */
595 spin_lock_bh(&xprt
->transport_lock
);
597 int timer
= task
->tk_msg
.rpc_proc
->p_timer
;
598 task
->tk_timeout
= rpc_calc_rto(clnt
->cl_rtt
, timer
);
599 task
->tk_timeout
<<= rpc_ntimeo(clnt
->cl_rtt
, timer
) + req
->rq_retries
;
600 if (task
->tk_timeout
> xprt
->timeout
.to_maxval
|| task
->tk_timeout
== 0)
601 task
->tk_timeout
= xprt
->timeout
.to_maxval
;
603 task
->tk_timeout
= req
->rq_timeout
;
604 /* Don't race with disconnect */
605 if (!xprt_connected(xprt
))
606 task
->tk_status
= -ENOTCONN
;
607 else if (!req
->rq_received
)
608 rpc_sleep_on(&xprt
->pending
, task
, NULL
, xprt_timer
);
609 __xprt_release_write(xprt
, task
);
610 spin_unlock_bh(&xprt
->transport_lock
);
613 static inline void do_xprt_reserve(struct rpc_task
*task
)
615 struct rpc_xprt
*xprt
= task
->tk_xprt
;
620 if (!list_empty(&xprt
->free
)) {
621 struct rpc_rqst
*req
= list_entry(xprt
->free
.next
, struct rpc_rqst
, rq_list
);
622 list_del_init(&req
->rq_list
);
623 task
->tk_rqstp
= req
;
624 xprt_request_init(task
, xprt
);
627 dprintk("RPC: waiting for request slot\n");
628 task
->tk_status
= -EAGAIN
;
629 task
->tk_timeout
= 0;
630 rpc_sleep_on(&xprt
->backlog
, task
, NULL
, NULL
);
634 * xprt_reserve - allocate an RPC request slot
635 * @task: RPC task requesting a slot allocation
637 * If no more slots are available, place the task on the transport's
640 void xprt_reserve(struct rpc_task
*task
)
642 struct rpc_xprt
*xprt
= task
->tk_xprt
;
644 task
->tk_status
= -EIO
;
645 if (!xprt
->shutdown
) {
646 spin_lock(&xprt
->reserve_lock
);
647 do_xprt_reserve(task
);
648 spin_unlock(&xprt
->reserve_lock
);
652 static inline u32
xprt_alloc_xid(struct rpc_xprt
*xprt
)
657 static inline void xprt_init_xid(struct rpc_xprt
*xprt
)
659 get_random_bytes(&xprt
->xid
, sizeof(xprt
->xid
));
662 static void xprt_request_init(struct rpc_task
*task
, struct rpc_xprt
*xprt
)
664 struct rpc_rqst
*req
= task
->tk_rqstp
;
666 req
->rq_timeout
= xprt
->timeout
.to_initval
;
669 req
->rq_xid
= xprt_alloc_xid(xprt
);
670 dprintk("RPC: %4d reserved req %p xid %08x\n", task
->tk_pid
,
671 req
, ntohl(req
->rq_xid
));
675 * xprt_release - release an RPC request slot
676 * @task: task which is finished with the slot
679 void xprt_release(struct rpc_task
*task
)
681 struct rpc_xprt
*xprt
= task
->tk_xprt
;
682 struct rpc_rqst
*req
;
684 if (!(req
= task
->tk_rqstp
))
686 spin_lock_bh(&xprt
->transport_lock
);
687 __xprt_release_write(xprt
, task
);
688 __xprt_put_cong(xprt
, req
);
689 if (!list_empty(&req
->rq_list
))
690 list_del(&req
->rq_list
);
691 xprt
->last_used
= jiffies
;
692 if (list_empty(&xprt
->recv
) && !xprt
->shutdown
)
693 mod_timer(&xprt
->timer
,
694 xprt
->last_used
+ RPC_IDLE_DISCONNECT_TIMEOUT
);
695 spin_unlock_bh(&xprt
->transport_lock
);
696 task
->tk_rqstp
= NULL
;
697 memset(req
, 0, sizeof(*req
)); /* mark unused */
699 dprintk("RPC: %4d release request %p\n", task
->tk_pid
, req
);
701 spin_lock(&xprt
->reserve_lock
);
702 list_add(&req
->rq_list
, &xprt
->free
);
703 xprt_clear_backlog(xprt
);
704 spin_unlock(&xprt
->reserve_lock
);
708 * xprt_set_timeout - set constant RPC timeout
709 * @to: RPC timeout parameters to set up
710 * @retr: number of retries
711 * @incr: amount of increase after each retry
714 void xprt_set_timeout(struct rpc_timeout
*to
, unsigned int retr
, unsigned long incr
)
717 to
->to_increment
= incr
;
718 to
->to_maxval
= to
->to_initval
+ (incr
* retr
);
719 to
->to_retries
= retr
;
720 to
->to_exponential
= 0;
723 static struct rpc_xprt
*xprt_setup(int proto
, struct sockaddr_in
*ap
, struct rpc_timeout
*to
)
726 struct rpc_xprt
*xprt
;
727 struct rpc_rqst
*req
;
729 if ((xprt
= kmalloc(sizeof(struct rpc_xprt
), GFP_KERNEL
)) == NULL
)
730 return ERR_PTR(-ENOMEM
);
731 memset(xprt
, 0, sizeof(*xprt
)); /* Nnnngh! */
737 result
= xs_setup_udp(xprt
, to
);
740 result
= xs_setup_tcp(xprt
, to
);
743 printk(KERN_ERR
"RPC: unrecognized transport protocol: %d\n",
750 return ERR_PTR(result
);
753 spin_lock_init(&xprt
->transport_lock
);
754 spin_lock_init(&xprt
->reserve_lock
);
755 init_waitqueue_head(&xprt
->cong_wait
);
757 INIT_LIST_HEAD(&xprt
->free
);
758 INIT_LIST_HEAD(&xprt
->recv
);
759 INIT_WORK(&xprt
->task_cleanup
, xprt_socket_autoclose
, xprt
);
760 init_timer(&xprt
->timer
);
761 xprt
->timer
.function
= xprt_init_autodisconnect
;
762 xprt
->timer
.data
= (unsigned long) xprt
;
763 xprt
->last_used
= jiffies
;
765 rpc_init_wait_queue(&xprt
->pending
, "xprt_pending");
766 rpc_init_wait_queue(&xprt
->sending
, "xprt_sending");
767 rpc_init_wait_queue(&xprt
->resend
, "xprt_resend");
768 rpc_init_priority_wait_queue(&xprt
->backlog
, "xprt_backlog");
770 /* initialize free list */
771 for (req
= &xprt
->slot
[xprt
->max_reqs
-1]; req
>= &xprt
->slot
[0]; req
--)
772 list_add(&req
->rq_list
, &xprt
->free
);
776 dprintk("RPC: created transport %p with %u slots\n", xprt
,
783 * xprt_create_proto - create an RPC client transport
784 * @proto: requested transport protocol
785 * @sap: remote peer's address
786 * @to: timeout parameters for new transport
789 struct rpc_xprt
*xprt_create_proto(int proto
, struct sockaddr_in
*sap
, struct rpc_timeout
*to
)
791 struct rpc_xprt
*xprt
;
793 xprt
= xprt_setup(proto
, sap
, to
);
795 dprintk("RPC: xprt_create_proto failed\n");
797 dprintk("RPC: xprt_create_proto created xprt %p\n", xprt
);
801 static void xprt_shutdown(struct rpc_xprt
*xprt
)
804 rpc_wake_up(&xprt
->sending
);
805 rpc_wake_up(&xprt
->resend
);
806 rpc_wake_up(&xprt
->pending
);
807 rpc_wake_up(&xprt
->backlog
);
808 wake_up(&xprt
->cong_wait
);
809 del_timer_sync(&xprt
->timer
);
812 static int xprt_clear_backlog(struct rpc_xprt
*xprt
) {
813 rpc_wake_up_next(&xprt
->backlog
);
814 wake_up(&xprt
->cong_wait
);
819 * xprt_destroy - destroy an RPC transport, killing off all requests.
820 * @xprt: transport to destroy
823 int xprt_destroy(struct rpc_xprt
*xprt
)
825 dprintk("RPC: destroying transport %p\n", xprt
);
827 xprt
->ops
->destroy(xprt
);