aboutsummaryrefslogtreecommitdiffstats
path: root/net/sunrpc
diff options
context:
space:
mode:
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/svc_xprt.c753
-rw-r--r--net/sunrpc/svcsock.c834
2 files changed, 777 insertions, 810 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 271467c5138d..23165aef59d9 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -35,10 +35,53 @@
35 35
36#define RPCDBG_FACILITY RPCDBG_SVCXPRT 36#define RPCDBG_FACILITY RPCDBG_SVCXPRT
37 37
38static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
39static int svc_deferred_recv(struct svc_rqst *rqstp);
40static struct cache_deferred_req *svc_defer(struct cache_req *req);
41static void svc_age_temp_xprts(unsigned long closure);
42
43/* apparently the "standard" is that clients close
44 * idle connections after 5 minutes, servers after
45 * 6 minutes
46 * http://www.connectathon.org/talks96/nfstcp.pdf
47 */
48static int svc_conn_age_period = 6*60;
49
38/* List of registered transport classes */ 50/* List of registered transport classes */
39static DEFINE_SPINLOCK(svc_xprt_class_lock); 51static DEFINE_SPINLOCK(svc_xprt_class_lock);
40static LIST_HEAD(svc_xprt_class_list); 52static LIST_HEAD(svc_xprt_class_list);
41 53
54/* SMP locking strategy:
55 *
56 * svc_pool->sp_lock protects most of the fields of that pool.
57 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
58 * when both need to be taken (rare), svc_serv->sv_lock is first.
59 * BKL protects svc_serv->sv_nrthread.
60 * svc_sock->sk_lock protects the svc_sock->sk_deferred list
61 * and the ->sk_info_authunix cache.
62 *
63 * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
64 * enqueued multiply. During normal transport processing this bit
65 * is set by svc_xprt_enqueue and cleared by svc_xprt_received.
66 * Providers should not manipulate this bit directly.
67 *
68 * Some flags can be set to certain values at any time
69 * providing that certain rules are followed:
70 *
71 * XPT_CONN, XPT_DATA:
72 * - Can be set or cleared at any time.
73 * - After a set, svc_xprt_enqueue must be called to enqueue
74 * the transport for processing.
75 * - After a clear, the transport must be read/accepted.
76 * If this succeeds, it must be set again.
77 * XPT_CLOSE:
78 * - Can set at any time. It is never cleared.
79 * XPT_DEAD:
80 * - Can only be set while XPT_BUSY is held which ensures
81 * that no other thread will be using the transport or will
82 * try to set XPT_DEAD.
83 */
84
42int svc_reg_xprt_class(struct svc_xprt_class *xcl) 85int svc_reg_xprt_class(struct svc_xprt_class *xcl)
43{ 86{
44 struct svc_xprt_class *cl; 87 struct svc_xprt_class *cl;
@@ -178,3 +221,713 @@ void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt)
178} 221}
179EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs); 222EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs);
180 223
224/**
225 * svc_print_addr - Format rq_addr field for printing
226 * @rqstp: svc_rqst struct containing address to print
227 * @buf: target buffer for formatted address
228 * @len: length of target buffer
229 *
230 */
231char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
232{
233 return __svc_print_addr(svc_addr(rqstp), buf, len);
234}
235EXPORT_SYMBOL_GPL(svc_print_addr);
236
237/*
238 * Queue up an idle server thread. Must have pool->sp_lock held.
239 * Note: this is really a stack rather than a queue, so that we only
240 * use as many different threads as we need, and the rest don't pollute
241 * the cache.
242 */
243static void svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp)
244{
245 list_add(&rqstp->rq_list, &pool->sp_threads);
246}
247
248/*
249 * Dequeue an nfsd thread. Must have pool->sp_lock held.
250 */
251static void svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp)
252{
253 list_del(&rqstp->rq_list);
254}
255
256/*
257 * Queue up a transport with data pending. If there are idle nfsd
258 * processes, wake 'em up.
259 *
260 */
261void svc_xprt_enqueue(struct svc_xprt *xprt)
262{
263 struct svc_serv *serv = xprt->xpt_server;
264 struct svc_pool *pool;
265 struct svc_rqst *rqstp;
266 int cpu;
267
268 if (!(xprt->xpt_flags &
269 ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
270 return;
271 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
272 return;
273
274 cpu = get_cpu();
275 pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
276 put_cpu();
277
278 spin_lock_bh(&pool->sp_lock);
279
280 if (!list_empty(&pool->sp_threads) &&
281 !list_empty(&pool->sp_sockets))
282 printk(KERN_ERR
283 "svc_xprt_enqueue: "
284 "threads and transports both waiting??\n");
285
286 if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
287 /* Don't enqueue dead transports */
288 dprintk("svc: transport %p is dead, not enqueued\n", xprt);
289 goto out_unlock;
290 }
291
292 /* Mark transport as busy. It will remain in this state until
293 * the provider calls svc_xprt_received. We update XPT_BUSY
294 * atomically because it also guards against trying to enqueue
295 * the transport twice.
296 */
297 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
298 /* Don't enqueue transport while already enqueued */
299 dprintk("svc: transport %p busy, not enqueued\n", xprt);
300 goto out_unlock;
301 }
302 BUG_ON(xprt->xpt_pool != NULL);
303 xprt->xpt_pool = pool;
304
305 /* Handle pending connection */
306 if (test_bit(XPT_CONN, &xprt->xpt_flags))
307 goto process;
308
309 /* Handle close in-progress */
310 if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
311 goto process;
312
313 /* Check if we have space to reply to a request */
314 if (!xprt->xpt_ops->xpo_has_wspace(xprt)) {
315 /* Don't enqueue while not enough space for reply */
316 dprintk("svc: no write space, transport %p not enqueued\n",
317 xprt);
318 xprt->xpt_pool = NULL;
319 clear_bit(XPT_BUSY, &xprt->xpt_flags);
320 goto out_unlock;
321 }
322
323 process:
324 if (!list_empty(&pool->sp_threads)) {
325 rqstp = list_entry(pool->sp_threads.next,
326 struct svc_rqst,
327 rq_list);
328 dprintk("svc: transport %p served by daemon %p\n",
329 xprt, rqstp);
330 svc_thread_dequeue(pool, rqstp);
331 if (rqstp->rq_xprt)
332 printk(KERN_ERR
333 "svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
334 rqstp, rqstp->rq_xprt);
335 rqstp->rq_xprt = xprt;
336 svc_xprt_get(xprt);
337 rqstp->rq_reserved = serv->sv_max_mesg;
338 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
339 BUG_ON(xprt->xpt_pool != pool);
340 wake_up(&rqstp->rq_wait);
341 } else {
342 dprintk("svc: transport %p put into queue\n", xprt);
343 list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
344 BUG_ON(xprt->xpt_pool != pool);
345 }
346
347out_unlock:
348 spin_unlock_bh(&pool->sp_lock);
349}
350EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
351
352/*
353 * Dequeue the first transport. Must be called with the pool->sp_lock held.
354 */
355static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
356{
357 struct svc_xprt *xprt;
358
359 if (list_empty(&pool->sp_sockets))
360 return NULL;
361
362 xprt = list_entry(pool->sp_sockets.next,
363 struct svc_xprt, xpt_ready);
364 list_del_init(&xprt->xpt_ready);
365
366 dprintk("svc: transport %p dequeued, inuse=%d\n",
367 xprt, atomic_read(&xprt->xpt_ref.refcount));
368
369 return xprt;
370}
371
372/*
373 * svc_xprt_received conditionally queues the transport for processing
374 * by another thread. The caller must hold the XPT_BUSY bit and must
375 * not thereafter touch transport data.
376 *
377 * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
378 * insufficient) data.
379 */
380void svc_xprt_received(struct svc_xprt *xprt)
381{
382 BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
383 xprt->xpt_pool = NULL;
384 clear_bit(XPT_BUSY, &xprt->xpt_flags);
385 svc_xprt_enqueue(xprt);
386}
387EXPORT_SYMBOL_GPL(svc_xprt_received);
388
389/**
390 * svc_reserve - change the space reserved for the reply to a request.
391 * @rqstp: The request in question
392 * @space: new max space to reserve
393 *
394 * Each request reserves some space on the output queue of the transport
395 * to make sure the reply fits. This function reduces that reserved
396 * space to be the amount of space used already, plus @space.
397 *
398 */
399void svc_reserve(struct svc_rqst *rqstp, int space)
400{
401 space += rqstp->rq_res.head[0].iov_len;
402
403 if (space < rqstp->rq_reserved) {
404 struct svc_xprt *xprt = rqstp->rq_xprt;
405 atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
406 rqstp->rq_reserved = space;
407
408 svc_xprt_enqueue(xprt);
409 }
410}
411
412static void svc_xprt_release(struct svc_rqst *rqstp)
413{
414 struct svc_xprt *xprt = rqstp->rq_xprt;
415
416 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
417
418 svc_free_res_pages(rqstp);
419 rqstp->rq_res.page_len = 0;
420 rqstp->rq_res.page_base = 0;
421
422 /* Reset response buffer and release
423 * the reservation.
424 * But first, check that enough space was reserved
425 * for the reply, otherwise we have a bug!
426 */
427 if ((rqstp->rq_res.len) > rqstp->rq_reserved)
428 printk(KERN_ERR "RPC request reserved %d but used %d\n",
429 rqstp->rq_reserved,
430 rqstp->rq_res.len);
431
432 rqstp->rq_res.head[0].iov_len = 0;
433 svc_reserve(rqstp, 0);
434 rqstp->rq_xprt = NULL;
435
436 svc_xprt_put(xprt);
437}
438
439/*
440 * External function to wake up a server waiting for data
441 * This really only makes sense for services like lockd
442 * which have exactly one thread anyway.
443 */
444void svc_wake_up(struct svc_serv *serv)
445{
446 struct svc_rqst *rqstp;
447 unsigned int i;
448 struct svc_pool *pool;
449
450 for (i = 0; i < serv->sv_nrpools; i++) {
451 pool = &serv->sv_pools[i];
452
453 spin_lock_bh(&pool->sp_lock);
454 if (!list_empty(&pool->sp_threads)) {
455 rqstp = list_entry(pool->sp_threads.next,
456 struct svc_rqst,
457 rq_list);
458 dprintk("svc: daemon %p woken up.\n", rqstp);
459 /*
460 svc_thread_dequeue(pool, rqstp);
461 rqstp->rq_xprt = NULL;
462 */
463 wake_up(&rqstp->rq_wait);
464 }
465 spin_unlock_bh(&pool->sp_lock);
466 }
467}
468
469int svc_port_is_privileged(struct sockaddr *sin)
470{
471 switch (sin->sa_family) {
472 case AF_INET:
473 return ntohs(((struct sockaddr_in *)sin)->sin_port)
474 < PROT_SOCK;
475 case AF_INET6:
476 return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
477 < PROT_SOCK;
478 default:
479 return 0;
480 }
481}
482
483/*
484 * Make sure that we don't have too many active connections. If we
485 * have, something must be dropped.
486 *
487 * There's no point in trying to do random drop here for DoS
488 * prevention. The NFS clients does 1 reconnect in 15 seconds. An
489 * attacker can easily beat that.
490 *
491 * The only somewhat efficient mechanism would be if drop old
492 * connections from the same IP first. But right now we don't even
493 * record the client IP in svc_sock.
494 */
495static void svc_check_conn_limits(struct svc_serv *serv)
496{
497 if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
498 struct svc_xprt *xprt = NULL;
499 spin_lock_bh(&serv->sv_lock);
500 if (!list_empty(&serv->sv_tempsocks)) {
501 if (net_ratelimit()) {
502 /* Try to help the admin */
503 printk(KERN_NOTICE "%s: too many open "
504 "connections, consider increasing the "
505 "number of nfsd threads\n",
506 serv->sv_name);
507 }
508 /*
509 * Always select the oldest connection. It's not fair,
510 * but so is life
511 */
512 xprt = list_entry(serv->sv_tempsocks.prev,
513 struct svc_xprt,
514 xpt_list);
515 set_bit(XPT_CLOSE, &xprt->xpt_flags);
516 svc_xprt_get(xprt);
517 }
518 spin_unlock_bh(&serv->sv_lock);
519
520 if (xprt) {
521 svc_xprt_enqueue(xprt);
522 svc_xprt_put(xprt);
523 }
524 }
525}
526
527/*
528 * Receive the next request on any transport. This code is carefully
529 * organised not to touch any cachelines in the shared svc_serv
530 * structure, only cachelines in the local svc_pool.
531 */
532int svc_recv(struct svc_rqst *rqstp, long timeout)
533{
534 struct svc_xprt *xprt = NULL;
535 struct svc_serv *serv = rqstp->rq_server;
536 struct svc_pool *pool = rqstp->rq_pool;
537 int len, i;
538 int pages;
539 struct xdr_buf *arg;
540 DECLARE_WAITQUEUE(wait, current);
541
542 dprintk("svc: server %p waiting for data (to = %ld)\n",
543 rqstp, timeout);
544
545 if (rqstp->rq_xprt)
546 printk(KERN_ERR
547 "svc_recv: service %p, transport not NULL!\n",
548 rqstp);
549 if (waitqueue_active(&rqstp->rq_wait))
550 printk(KERN_ERR
551 "svc_recv: service %p, wait queue active!\n",
552 rqstp);
553
554 /* now allocate needed pages. If we get a failure, sleep briefly */
555 pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
556 for (i = 0; i < pages ; i++)
557 while (rqstp->rq_pages[i] == NULL) {
558 struct page *p = alloc_page(GFP_KERNEL);
559 if (!p) {
560 int j = msecs_to_jiffies(500);
561 schedule_timeout_uninterruptible(j);
562 }
563 rqstp->rq_pages[i] = p;
564 }
565 rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
566 BUG_ON(pages >= RPCSVC_MAXPAGES);
567
568 /* Make arg->head point to first page and arg->pages point to rest */
569 arg = &rqstp->rq_arg;
570 arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
571 arg->head[0].iov_len = PAGE_SIZE;
572 arg->pages = rqstp->rq_pages + 1;
573 arg->page_base = 0;
574 /* save at least one page for response */
575 arg->page_len = (pages-2)*PAGE_SIZE;
576 arg->len = (pages-1)*PAGE_SIZE;
577 arg->tail[0].iov_len = 0;
578
579 try_to_freeze();
580 cond_resched();
581 if (signalled())
582 return -EINTR;
583
584 spin_lock_bh(&pool->sp_lock);
585 xprt = svc_xprt_dequeue(pool);
586 if (xprt) {
587 rqstp->rq_xprt = xprt;
588 svc_xprt_get(xprt);
589 rqstp->rq_reserved = serv->sv_max_mesg;
590 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
591 } else {
592 /* No data pending. Go to sleep */
593 svc_thread_enqueue(pool, rqstp);
594
595 /*
596 * We have to be able to interrupt this wait
597 * to bring down the daemons ...
598 */
599 set_current_state(TASK_INTERRUPTIBLE);
600 add_wait_queue(&rqstp->rq_wait, &wait);
601 spin_unlock_bh(&pool->sp_lock);
602
603 schedule_timeout(timeout);
604
605 try_to_freeze();
606
607 spin_lock_bh(&pool->sp_lock);
608 remove_wait_queue(&rqstp->rq_wait, &wait);
609
610 xprt = rqstp->rq_xprt;
611 if (!xprt) {
612 svc_thread_dequeue(pool, rqstp);
613 spin_unlock_bh(&pool->sp_lock);
614 dprintk("svc: server %p, no data yet\n", rqstp);
615 return signalled()? -EINTR : -EAGAIN;
616 }
617 }
618 spin_unlock_bh(&pool->sp_lock);
619
620 len = 0;
621 if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
622 dprintk("svc_recv: found XPT_CLOSE\n");
623 svc_delete_xprt(xprt);
624 } else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
625 struct svc_xprt *newxpt;
626 newxpt = xprt->xpt_ops->xpo_accept(xprt);
627 if (newxpt) {
628 /*
629 * We know this module_get will succeed because the
630 * listener holds a reference too
631 */
632 __module_get(newxpt->xpt_class->xcl_owner);
633 svc_check_conn_limits(xprt->xpt_server);
634 spin_lock_bh(&serv->sv_lock);
635 set_bit(XPT_TEMP, &newxpt->xpt_flags);
636 list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
637 serv->sv_tmpcnt++;
638 if (serv->sv_temptimer.function == NULL) {
639 /* setup timer to age temp transports */
640 setup_timer(&serv->sv_temptimer,
641 svc_age_temp_xprts,
642 (unsigned long)serv);
643 mod_timer(&serv->sv_temptimer,
644 jiffies + svc_conn_age_period * HZ);
645 }
646 spin_unlock_bh(&serv->sv_lock);
647 svc_xprt_received(newxpt);
648 }
649 svc_xprt_received(xprt);
650 } else {
651 dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
652 rqstp, pool->sp_id, xprt,
653 atomic_read(&xprt->xpt_ref.refcount));
654 rqstp->rq_deferred = svc_deferred_dequeue(xprt);
655 if (rqstp->rq_deferred) {
656 svc_xprt_received(xprt);
657 len = svc_deferred_recv(rqstp);
658 } else
659 len = xprt->xpt_ops->xpo_recvfrom(rqstp);
660 dprintk("svc: got len=%d\n", len);
661 }
662
663 /* No data, incomplete (TCP) read, or accept() */
664 if (len == 0 || len == -EAGAIN) {
665 rqstp->rq_res.len = 0;
666 svc_xprt_release(rqstp);
667 return -EAGAIN;
668 }
669 clear_bit(XPT_OLD, &xprt->xpt_flags);
670
671 rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
672 rqstp->rq_chandle.defer = svc_defer;
673
674 if (serv->sv_stats)
675 serv->sv_stats->netcnt++;
676 return len;
677}
678
679/*
680 * Drop request
681 */
682void svc_drop(struct svc_rqst *rqstp)
683{
684 dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
685 svc_xprt_release(rqstp);
686}
687
688/*
689 * Return reply to client.
690 */
691int svc_send(struct svc_rqst *rqstp)
692{
693 struct svc_xprt *xprt;
694 int len;
695 struct xdr_buf *xb;
696
697 xprt = rqstp->rq_xprt;
698 if (!xprt)
699 return -EFAULT;
700
701 /* release the receive skb before sending the reply */
702 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
703
704 /* calculate over-all length */
705 xb = &rqstp->rq_res;
706 xb->len = xb->head[0].iov_len +
707 xb->page_len +
708 xb->tail[0].iov_len;
709
710 /* Grab mutex to serialize outgoing data. */
711 mutex_lock(&xprt->xpt_mutex);
712 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
713 len = -ENOTCONN;
714 else
715 len = xprt->xpt_ops->xpo_sendto(rqstp);
716 mutex_unlock(&xprt->xpt_mutex);
717 svc_xprt_release(rqstp);
718
719 if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
720 return 0;
721 return len;
722}
723
724/*
725 * Timer function to close old temporary transports, using
726 * a mark-and-sweep algorithm.
727 */
728static void svc_age_temp_xprts(unsigned long closure)
729{
730 struct svc_serv *serv = (struct svc_serv *)closure;
731 struct svc_xprt *xprt;
732 struct list_head *le, *next;
733 LIST_HEAD(to_be_aged);
734
735 dprintk("svc_age_temp_xprts\n");
736
737 if (!spin_trylock_bh(&serv->sv_lock)) {
738 /* busy, try again 1 sec later */
739 dprintk("svc_age_temp_xprts: busy\n");
740 mod_timer(&serv->sv_temptimer, jiffies + HZ);
741 return;
742 }
743
744 list_for_each_safe(le, next, &serv->sv_tempsocks) {
745 xprt = list_entry(le, struct svc_xprt, xpt_list);
746
747 /* First time through, just mark it OLD. Second time
748 * through, close it. */
749 if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags))
750 continue;
751 if (atomic_read(&xprt->xpt_ref.refcount) > 1
752 || test_bit(XPT_BUSY, &xprt->xpt_flags))
753 continue;
754 svc_xprt_get(xprt);
755 list_move(le, &to_be_aged);
756 set_bit(XPT_CLOSE, &xprt->xpt_flags);
757 set_bit(XPT_DETACHED, &xprt->xpt_flags);
758 }
759 spin_unlock_bh(&serv->sv_lock);
760
761 while (!list_empty(&to_be_aged)) {
762 le = to_be_aged.next;
763 /* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
764 list_del_init(le);
765 xprt = list_entry(le, struct svc_xprt, xpt_list);
766
767 dprintk("queuing xprt %p for closing\n", xprt);
768
769 /* a thread will dequeue and close it soon */
770 svc_xprt_enqueue(xprt);
771 svc_xprt_put(xprt);
772 }
773
774 mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
775}
776
777/*
778 * Remove a dead transport
779 */
780void svc_delete_xprt(struct svc_xprt *xprt)
781{
782 struct svc_serv *serv = xprt->xpt_server;
783
784 dprintk("svc: svc_delete_xprt(%p)\n", xprt);
785 xprt->xpt_ops->xpo_detach(xprt);
786
787 spin_lock_bh(&serv->sv_lock);
788 if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags))
789 list_del_init(&xprt->xpt_list);
790 /*
791 * We used to delete the transport from whichever list
792 * it's sk_xprt.xpt_ready node was on, but we don't actually
793 * need to. This is because the only time we're called
794 * while still attached to a queue, the queue itself
795 * is about to be destroyed (in svc_destroy).
796 */
797 if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
798 BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
799 if (test_bit(XPT_TEMP, &xprt->xpt_flags))
800 serv->sv_tmpcnt--;
801 svc_xprt_put(xprt);
802 }
803 spin_unlock_bh(&serv->sv_lock);
804}
805
806void svc_close_xprt(struct svc_xprt *xprt)
807{
808 set_bit(XPT_CLOSE, &xprt->xpt_flags);
809 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
810 /* someone else will have to effect the close */
811 return;
812
813 svc_xprt_get(xprt);
814 svc_delete_xprt(xprt);
815 clear_bit(XPT_BUSY, &xprt->xpt_flags);
816 svc_xprt_put(xprt);
817}
818
819void svc_close_all(struct list_head *xprt_list)
820{
821 struct svc_xprt *xprt;
822 struct svc_xprt *tmp;
823
824 list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
825 set_bit(XPT_CLOSE, &xprt->xpt_flags);
826 if (test_bit(XPT_BUSY, &xprt->xpt_flags)) {
827 /* Waiting to be processed, but no threads left,
828 * So just remove it from the waiting list
829 */
830 list_del_init(&xprt->xpt_ready);
831 clear_bit(XPT_BUSY, &xprt->xpt_flags);
832 }
833 svc_close_xprt(xprt);
834 }
835}
836
837/*
838 * Handle defer and revisit of requests
839 */
840
841static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
842{
843 struct svc_deferred_req *dr =
844 container_of(dreq, struct svc_deferred_req, handle);
845 struct svc_xprt *xprt = dr->xprt;
846
847 if (too_many) {
848 svc_xprt_put(xprt);
849 kfree(dr);
850 return;
851 }
852 dprintk("revisit queued\n");
853 dr->xprt = NULL;
854 spin_lock(&xprt->xpt_lock);
855 list_add(&dr->handle.recent, &xprt->xpt_deferred);
856 spin_unlock(&xprt->xpt_lock);
857 set_bit(XPT_DEFERRED, &xprt->xpt_flags);
858 svc_xprt_enqueue(xprt);
859 svc_xprt_put(xprt);
860}
861
862static struct cache_deferred_req *svc_defer(struct cache_req *req)
863{
864 struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
865 int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
866 struct svc_deferred_req *dr;
867
868 if (rqstp->rq_arg.page_len)
869 return NULL; /* if more than a page, give up FIXME */
870 if (rqstp->rq_deferred) {
871 dr = rqstp->rq_deferred;
872 rqstp->rq_deferred = NULL;
873 } else {
874 int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
875 /* FIXME maybe discard if size too large */
876 dr = kmalloc(size, GFP_KERNEL);
877 if (dr == NULL)
878 return NULL;
879
880 dr->handle.owner = rqstp->rq_server;
881 dr->prot = rqstp->rq_prot;
882 memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
883 dr->addrlen = rqstp->rq_addrlen;
884 dr->daddr = rqstp->rq_daddr;
885 dr->argslen = rqstp->rq_arg.len >> 2;
886 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip,
887 dr->argslen<<2);
888 }
889 svc_xprt_get(rqstp->rq_xprt);
890 dr->xprt = rqstp->rq_xprt;
891
892 dr->handle.revisit = svc_revisit;
893 return &dr->handle;
894}
895
896/*
897 * recv data from a deferred request into an active one
898 */
899static int svc_deferred_recv(struct svc_rqst *rqstp)
900{
901 struct svc_deferred_req *dr = rqstp->rq_deferred;
902
903 rqstp->rq_arg.head[0].iov_base = dr->args;
904 rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
905 rqstp->rq_arg.page_len = 0;
906 rqstp->rq_arg.len = dr->argslen<<2;
907 rqstp->rq_prot = dr->prot;
908 memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
909 rqstp->rq_addrlen = dr->addrlen;
910 rqstp->rq_daddr = dr->daddr;
911 rqstp->rq_respages = rqstp->rq_pages;
912 return dr->argslen<<2;
913}
914
915
916static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
917{
918 struct svc_deferred_req *dr = NULL;
919
920 if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
921 return NULL;
922 spin_lock(&xprt->xpt_lock);
923 clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
924 if (!list_empty(&xprt->xpt_deferred)) {
925 dr = list_entry(xprt->xpt_deferred.next,
926 struct svc_deferred_req,
927 handle.recent);
928 list_del_init(&dr->handle.recent);
929 set_bit(XPT_DEFERRED, &xprt->xpt_flags);
930 }
931 spin_unlock(&xprt->xpt_lock);
932 return dr;
933}
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 0814a78ad7ad..343a85b700f0 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -48,66 +48,24 @@
48#include <linux/sunrpc/svcsock.h> 48#include <linux/sunrpc/svcsock.h>
49#include <linux/sunrpc/stats.h> 49#include <linux/sunrpc/stats.h>
50 50
51/* SMP locking strategy:
52 *
53 * svc_pool->sp_lock protects most of the fields of that pool.
54 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
55 * when both need to be taken (rare), svc_serv->sv_lock is first.
56 * BKL protects svc_serv->sv_nrthread.
57 * svc_sock->sk_lock protects the svc_sock->sk_deferred list
58 * and the ->sk_info_authunix cache.
59 * svc_sock->sk_xprt.xpt_flags.XPT_BUSY prevents a svc_sock being
60 * enqueued multiply.
61 *
62 * Some flags can be set to certain values at any time
63 * providing that certain rules are followed:
64 *
65 * XPT_CONN, XPT_DATA, can be set or cleared at any time.
66 * after a set, svc_xprt_enqueue must be called.
67 * after a clear, the socket must be read/accepted
68 * if this succeeds, it must be set again.
69 * XPT_CLOSE can set at any time. It is never cleared.
70 * xpt_ref contains a bias of '1' until XPT_DEAD is set.
71 * so when xprt_ref hits zero, we know the transport is dead
72 * and no-one is using it.
73 * XPT_DEAD can only be set while XPT_BUSY is held which ensures
74 * no other thread will be using the socket or will try to
75 * set XPT_DEAD.
76 *
77 */
78
79#define RPCDBG_FACILITY RPCDBG_SVCXPRT 51#define RPCDBG_FACILITY RPCDBG_SVCXPRT
80 52
81 53
82static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, 54static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
83 int *errp, int flags); 55 int *errp, int flags);
84static void svc_delete_xprt(struct svc_xprt *xprt);
85static void svc_udp_data_ready(struct sock *, int); 56static void svc_udp_data_ready(struct sock *, int);
86static int svc_udp_recvfrom(struct svc_rqst *); 57static int svc_udp_recvfrom(struct svc_rqst *);
87static int svc_udp_sendto(struct svc_rqst *); 58static int svc_udp_sendto(struct svc_rqst *);
88static void svc_close_xprt(struct svc_xprt *xprt);
89static void svc_sock_detach(struct svc_xprt *); 59static void svc_sock_detach(struct svc_xprt *);
90static void svc_sock_free(struct svc_xprt *); 60static void svc_sock_free(struct svc_xprt *);
91 61
92static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
93static int svc_deferred_recv(struct svc_rqst *rqstp);
94static struct cache_deferred_req *svc_defer(struct cache_req *req);
95static struct svc_xprt *svc_create_socket(struct svc_serv *, int, 62static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
96 struct sockaddr *, int, int); 63 struct sockaddr *, int, int);
97static void svc_age_temp_xprts(unsigned long closure);
98
99/* apparently the "standard" is that clients close
100 * idle connections after 5 minutes, servers after
101 * 6 minutes
102 * http://www.connectathon.org/talks96/nfstcp.pdf
103 */
104static int svc_conn_age_period = 6*60;
105
106#ifdef CONFIG_DEBUG_LOCK_ALLOC 64#ifdef CONFIG_DEBUG_LOCK_ALLOC
107static struct lock_class_key svc_key[2]; 65static struct lock_class_key svc_key[2];
108static struct lock_class_key svc_slock_key[2]; 66static struct lock_class_key svc_slock_key[2];
109 67
110static inline void svc_reclassify_socket(struct socket *sock) 68static void svc_reclassify_socket(struct socket *sock)
111{ 69{
112 struct sock *sk = sock->sk; 70 struct sock *sk = sock->sk;
113 BUG_ON(sock_owned_by_user(sk)); 71 BUG_ON(sock_owned_by_user(sk));
@@ -131,67 +89,11 @@ static inline void svc_reclassify_socket(struct socket *sock)
131 } 89 }
132} 90}
133#else 91#else
134static inline void svc_reclassify_socket(struct socket *sock) 92static void svc_reclassify_socket(struct socket *sock)
135{ 93{
136} 94}
137#endif 95#endif
138 96
139static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len)
140{
141 switch (addr->sa_family) {
142 case AF_INET:
143 snprintf(buf, len, "%u.%u.%u.%u, port=%u",
144 NIPQUAD(((struct sockaddr_in *) addr)->sin_addr),
145 ntohs(((struct sockaddr_in *) addr)->sin_port));
146 break;
147
148 case AF_INET6:
149 snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u",
150 NIP6(((struct sockaddr_in6 *) addr)->sin6_addr),
151 ntohs(((struct sockaddr_in6 *) addr)->sin6_port));
152 break;
153
154 default:
155 snprintf(buf, len, "unknown address type: %d", addr->sa_family);
156 break;
157 }
158 return buf;
159}
160
161/**
162 * svc_print_addr - Format rq_addr field for printing
163 * @rqstp: svc_rqst struct containing address to print
164 * @buf: target buffer for formatted address
165 * @len: length of target buffer
166 *
167 */
168char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
169{
170 return __svc_print_addr(svc_addr(rqstp), buf, len);
171}
172EXPORT_SYMBOL_GPL(svc_print_addr);
173
174/*
175 * Queue up an idle server thread. Must have pool->sp_lock held.
176 * Note: this is really a stack rather than a queue, so that we only
177 * use as many different threads as we need, and the rest don't pollute
178 * the cache.
179 */
180static inline void
181svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp)
182{
183 list_add(&rqstp->rq_list, &pool->sp_threads);
184}
185
186/*
187 * Dequeue an nfsd thread. Must have pool->sp_lock held.
188 */
189static inline void
190svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp)
191{
192 list_del(&rqstp->rq_list);
193}
194
195/* 97/*
196 * Release an skbuff after use 98 * Release an skbuff after use
197 */ 99 */
@@ -214,220 +116,6 @@ static void svc_release_skb(struct svc_rqst *rqstp)
214 } 116 }
215} 117}
216 118
217/*
218 * Queue up a socket with data pending. If there are idle nfsd
219 * processes, wake 'em up.
220 *
221 */
222void svc_xprt_enqueue(struct svc_xprt *xprt)
223{
224 struct svc_serv *serv = xprt->xpt_server;
225 struct svc_pool *pool;
226 struct svc_rqst *rqstp;
227 int cpu;
228
229 if (!(xprt->xpt_flags &
230 ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
231 return;
232 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
233 return;
234
235 cpu = get_cpu();
236 pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
237 put_cpu();
238
239 spin_lock_bh(&pool->sp_lock);
240
241 if (!list_empty(&pool->sp_threads) &&
242 !list_empty(&pool->sp_sockets))
243 printk(KERN_ERR
244 "svc_xprt_enqueue: "
245 "threads and transports both waiting??\n");
246
247 if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
248 /* Don't enqueue dead sockets */
249 dprintk("svc: transport %p is dead, not enqueued\n", xprt);
250 goto out_unlock;
251 }
252
253 /* Mark socket as busy. It will remain in this state until the
254 * server has processed all pending data and put the socket back
255 * on the idle list. We update XPT_BUSY atomically because
256 * it also guards against trying to enqueue the svc_sock twice.
257 */
258 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
259 /* Don't enqueue socket while already enqueued */
260 dprintk("svc: transport %p busy, not enqueued\n", xprt);
261 goto out_unlock;
262 }
263 BUG_ON(xprt->xpt_pool != NULL);
264 xprt->xpt_pool = pool;
265
266 /* Handle pending connection */
267 if (test_bit(XPT_CONN, &xprt->xpt_flags))
268 goto process;
269
270 /* Handle close in-progress */
271 if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
272 goto process;
273
274 /* Check if we have space to reply to a request */
275 if (!xprt->xpt_ops->xpo_has_wspace(xprt)) {
276 /* Don't enqueue while not enough space for reply */
277 dprintk("svc: no write space, transport %p not enqueued\n",
278 xprt);
279 xprt->xpt_pool = NULL;
280 clear_bit(XPT_BUSY, &xprt->xpt_flags);
281 goto out_unlock;
282 }
283
284 process:
285 if (!list_empty(&pool->sp_threads)) {
286 rqstp = list_entry(pool->sp_threads.next,
287 struct svc_rqst,
288 rq_list);
289 dprintk("svc: transport %p served by daemon %p\n",
290 xprt, rqstp);
291 svc_thread_dequeue(pool, rqstp);
292 if (rqstp->rq_xprt)
293 printk(KERN_ERR
294 "svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
295 rqstp, rqstp->rq_xprt);
296 rqstp->rq_xprt = xprt;
297 svc_xprt_get(xprt);
298 rqstp->rq_reserved = serv->sv_max_mesg;
299 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
300 BUG_ON(xprt->xpt_pool != pool);
301 wake_up(&rqstp->rq_wait);
302 } else {
303 dprintk("svc: transport %p put into queue\n", xprt);
304 list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
305 BUG_ON(xprt->xpt_pool != pool);
306 }
307
308out_unlock:
309 spin_unlock_bh(&pool->sp_lock);
310}
311EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
312
313/*
314 * Dequeue the first socket. Must be called with the pool->sp_lock held.
315 */
316static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
317{
318 struct svc_xprt *xprt;
319
320 if (list_empty(&pool->sp_sockets))
321 return NULL;
322
323 xprt = list_entry(pool->sp_sockets.next,
324 struct svc_xprt, xpt_ready);
325 list_del_init(&xprt->xpt_ready);
326
327 dprintk("svc: transport %p dequeued, inuse=%d\n",
328 xprt, atomic_read(&xprt->xpt_ref.refcount));
329
330 return xprt;
331}
332
333/*
334 * svc_xprt_received conditionally queues the transport for processing
335 * by another thread. The caller must hold the XPT_BUSY bit and must
336 * not thereafter touch transport data.
337 *
338 * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
339 * insufficient) data.
340 */
341void svc_xprt_received(struct svc_xprt *xprt)
342{
343 BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
344 xprt->xpt_pool = NULL;
345 clear_bit(XPT_BUSY, &xprt->xpt_flags);
346 svc_xprt_enqueue(xprt);
347}
348EXPORT_SYMBOL_GPL(svc_xprt_received);
349
350/**
351 * svc_reserve - change the space reserved for the reply to a request.
352 * @rqstp: The request in question
353 * @space: new max space to reserve
354 *
355 * Each request reserves some space on the output queue of the socket
356 * to make sure the reply fits. This function reduces that reserved
357 * space to be the amount of space used already, plus @space.
358 *
359 */
360void svc_reserve(struct svc_rqst *rqstp, int space)
361{
362 space += rqstp->rq_res.head[0].iov_len;
363
364 if (space < rqstp->rq_reserved) {
365 struct svc_xprt *xprt = rqstp->rq_xprt;
366 atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
367 rqstp->rq_reserved = space;
368
369 svc_xprt_enqueue(xprt);
370 }
371}
372
373static void svc_xprt_release(struct svc_rqst *rqstp)
374{
375 struct svc_xprt *xprt = rqstp->rq_xprt;
376
377 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
378
379 svc_free_res_pages(rqstp);
380 rqstp->rq_res.page_len = 0;
381 rqstp->rq_res.page_base = 0;
382
383 /* Reset response buffer and release
384 * the reservation.
385 * But first, check that enough space was reserved
386 * for the reply, otherwise we have a bug!
387 */
388 if ((rqstp->rq_res.len) > rqstp->rq_reserved)
389 printk(KERN_ERR "RPC request reserved %d but used %d\n",
390 rqstp->rq_reserved,
391 rqstp->rq_res.len);
392
393 rqstp->rq_res.head[0].iov_len = 0;
394 svc_reserve(rqstp, 0);
395 rqstp->rq_xprt = NULL;
396
397 svc_xprt_put(xprt);
398}
399
400/*
401 * External function to wake up a server waiting for data
402 * This really only makes sense for services like lockd
403 * which have exactly one thread anyway.
404 */
405void
406svc_wake_up(struct svc_serv *serv)
407{
408 struct svc_rqst *rqstp;
409 unsigned int i;
410 struct svc_pool *pool;
411
412 for (i = 0; i < serv->sv_nrpools; i++) {
413 pool = &serv->sv_pools[i];
414
415 spin_lock_bh(&pool->sp_lock);
416 if (!list_empty(&pool->sp_threads)) {
417 rqstp = list_entry(pool->sp_threads.next,
418 struct svc_rqst,
419 rq_list);
420 dprintk("svc: daemon %p woken up.\n", rqstp);
421 /*
422 svc_thread_dequeue(pool, rqstp);
423 rqstp->rq_xprt = NULL;
424 */
425 wake_up(&rqstp->rq_wait);
426 }
427 spin_unlock_bh(&pool->sp_lock);
428 }
429}
430
431union svc_pktinfo_u { 119union svc_pktinfo_u {
432 struct in_pktinfo pkti; 120 struct in_pktinfo pkti;
433 struct in6_pktinfo pkti6; 121 struct in6_pktinfo pkti6;
@@ -469,8 +157,7 @@ static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
469/* 157/*
470 * Generic sendto routine 158 * Generic sendto routine
471 */ 159 */
472static int 160static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
473svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
474{ 161{
475 struct svc_sock *svsk = 162 struct svc_sock *svsk =
476 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 163 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@@ -605,8 +292,7 @@ EXPORT_SYMBOL(svc_sock_names);
605/* 292/*
606 * Check input queue length 293 * Check input queue length
607 */ 294 */
608static int 295static int svc_recv_available(struct svc_sock *svsk)
609svc_recv_available(struct svc_sock *svsk)
610{ 296{
611 struct socket *sock = svsk->sk_sock; 297 struct socket *sock = svsk->sk_sock;
612 int avail, err; 298 int avail, err;
@@ -619,8 +305,8 @@ svc_recv_available(struct svc_sock *svsk)
619/* 305/*
620 * Generic recvfrom routine. 306 * Generic recvfrom routine.
621 */ 307 */
622static int 308static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
623svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen) 309 int buflen)
624{ 310{
625 struct svc_sock *svsk = 311 struct svc_sock *svsk =
626 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 312 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@@ -640,8 +326,8 @@ svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen)
640/* 326/*
641 * Set socket snd and rcv buffer lengths 327 * Set socket snd and rcv buffer lengths
642 */ 328 */
643static inline void 329static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
644svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv) 330 unsigned int rcv)
645{ 331{
646#if 0 332#if 0
647 mm_segment_t oldfs; 333 mm_segment_t oldfs;
@@ -666,8 +352,7 @@ svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv)
666/* 352/*
667 * INET callback when data has been received on the socket. 353 * INET callback when data has been received on the socket.
668 */ 354 */
669static void 355static void svc_udp_data_ready(struct sock *sk, int count)
670svc_udp_data_ready(struct sock *sk, int count)
671{ 356{
672 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 357 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
673 358
@@ -685,8 +370,7 @@ svc_udp_data_ready(struct sock *sk, int count)
685/* 370/*
686 * INET callback when space is newly available on the socket. 371 * INET callback when space is newly available on the socket.
687 */ 372 */
688static void 373static void svc_write_space(struct sock *sk)
689svc_write_space(struct sock *sk)
690{ 374{
691 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); 375 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
692 376
@@ -732,8 +416,7 @@ static void svc_udp_get_dest_address(struct svc_rqst *rqstp,
732/* 416/*
733 * Receive a datagram from a UDP socket. 417 * Receive a datagram from a UDP socket.
734 */ 418 */
735static int 419static int svc_udp_recvfrom(struct svc_rqst *rqstp)
736svc_udp_recvfrom(struct svc_rqst *rqstp)
737{ 420{
738 struct svc_sock *svsk = 421 struct svc_sock *svsk =
739 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 422 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@@ -827,7 +510,8 @@ svc_udp_recvfrom(struct svc_rqst *rqstp)
827 skb_free_datagram(svsk->sk_sk, skb); 510 skb_free_datagram(svsk->sk_sk, skb);
828 } else { 511 } else {
829 /* we can use it in-place */ 512 /* we can use it in-place */
830 rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr); 513 rqstp->rq_arg.head[0].iov_base = skb->data +
514 sizeof(struct udphdr);
831 rqstp->rq_arg.head[0].iov_len = len; 515 rqstp->rq_arg.head[0].iov_len = len;
832 if (skb_checksum_complete(skb)) { 516 if (skb_checksum_complete(skb)) {
833 skb_free_datagram(svsk->sk_sk, skb); 517 skb_free_datagram(svsk->sk_sk, skb);
@@ -938,7 +622,8 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
938 3 * svsk->sk_xprt.xpt_server->sv_max_mesg, 622 3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
939 3 * svsk->sk_xprt.xpt_server->sv_max_mesg); 623 3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
940 624
941 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* might have come in before data_ready set up */ 625 /* data might have come in before data_ready set up */
626 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
942 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); 627 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
943 628
944 oldfs = get_fs(); 629 oldfs = get_fs();
@@ -953,8 +638,7 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
953 * A data_ready event on a listening socket means there's a connection 638 * A data_ready event on a listening socket means there's a connection
954 * pending. Do not use state_change as a substitute for it. 639 * pending. Do not use state_change as a substitute for it.
955 */ 640 */
956static void 641static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
957svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
958{ 642{
959 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 643 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
960 644
@@ -986,8 +670,7 @@ svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
986/* 670/*
987 * A state change on a connected socket means it's dying or dead. 671 * A state change on a connected socket means it's dying or dead.
988 */ 672 */
989static void 673static void svc_tcp_state_change(struct sock *sk)
990svc_tcp_state_change(struct sock *sk)
991{ 674{
992 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 675 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
993 676
@@ -1004,8 +687,7 @@ svc_tcp_state_change(struct sock *sk)
1004 wake_up_interruptible_all(sk->sk_sleep); 687 wake_up_interruptible_all(sk->sk_sleep);
1005} 688}
1006 689
1007static void 690static void svc_tcp_data_ready(struct sock *sk, int count)
1008svc_tcp_data_ready(struct sock *sk, int count)
1009{ 691{
1010 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 692 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
1011 693
@@ -1019,20 +701,6 @@ svc_tcp_data_ready(struct sock *sk, int count)
1019 wake_up_interruptible(sk->sk_sleep); 701 wake_up_interruptible(sk->sk_sleep);
1020} 702}
1021 703
1022static inline int svc_port_is_privileged(struct sockaddr *sin)
1023{
1024 switch (sin->sa_family) {
1025 case AF_INET:
1026 return ntohs(((struct sockaddr_in *)sin)->sin_port)
1027 < PROT_SOCK;
1028 case AF_INET6:
1029 return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
1030 < PROT_SOCK;
1031 default:
1032 return 0;
1033 }
1034}
1035
1036/* 704/*
1037 * Accept a TCP connection 705 * Accept a TCP connection
1038 */ 706 */
@@ -1115,8 +783,7 @@ failed:
1115/* 783/*
1116 * Receive data from a TCP socket. 784 * Receive data from a TCP socket.
1117 */ 785 */
1118static int 786static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1119svc_tcp_recvfrom(struct svc_rqst *rqstp)
1120{ 787{
1121 struct svc_sock *svsk = 788 struct svc_sock *svsk =
1122 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); 789 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
@@ -1269,8 +936,7 @@ svc_tcp_recvfrom(struct svc_rqst *rqstp)
1269/* 936/*
1270 * Send out data on TCP socket. 937 * Send out data on TCP socket.
1271 */ 938 */
1272static int 939static int svc_tcp_sendto(struct svc_rqst *rqstp)
1273svc_tcp_sendto(struct svc_rqst *rqstp)
1274{ 940{
1275 struct xdr_buf *xbufp = &rqstp->rq_res; 941 struct xdr_buf *xbufp = &rqstp->rq_res;
1276 int sent; 942 int sent;
@@ -1288,7 +954,9 @@ svc_tcp_sendto(struct svc_rqst *rqstp)
1288 954
1289 sent = svc_sendto(rqstp, &rqstp->rq_res); 955 sent = svc_sendto(rqstp, &rqstp->rq_res);
1290 if (sent != xbufp->len) { 956 if (sent != xbufp->len) {
1291 printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n", 957 printk(KERN_NOTICE
958 "rpc-srv/tcp: %s: %s %d when sending %d bytes "
959 "- shutting down socket\n",
1292 rqstp->rq_xprt->xpt_server->sv_name, 960 rqstp->rq_xprt->xpt_server->sv_name,
1293 (sent<0)?"got error":"sent only", 961 (sent<0)?"got error":"sent only",
1294 sent, xbufp->len); 962 sent, xbufp->len);
@@ -1410,8 +1078,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1410 } 1078 }
1411} 1079}
1412 1080
1413void 1081void svc_sock_update_bufs(struct svc_serv *serv)
1414svc_sock_update_bufs(struct svc_serv *serv)
1415{ 1082{
1416 /* 1083 /*
1417 * The number of server threads has changed. Update 1084 * The number of server threads has changed. Update
@@ -1434,302 +1101,6 @@ svc_sock_update_bufs(struct svc_serv *serv)
1434} 1101}
1435 1102
1436/* 1103/*
1437 * Make sure that we don't have too many active connections. If we
1438 * have, something must be dropped.
1439 *
1440 * There's no point in trying to do random drop here for DoS
1441 * prevention. The NFS clients does 1 reconnect in 15 seconds. An
1442 * attacker can easily beat that.
1443 *
1444 * The only somewhat efficient mechanism would be if drop old
1445 * connections from the same IP first. But right now we don't even
1446 * record the client IP in svc_sock.
1447 */
1448static void svc_check_conn_limits(struct svc_serv *serv)
1449{
1450 if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
1451 struct svc_xprt *xprt = NULL;
1452 spin_lock_bh(&serv->sv_lock);
1453 if (!list_empty(&serv->sv_tempsocks)) {
1454 if (net_ratelimit()) {
1455 /* Try to help the admin */
1456 printk(KERN_NOTICE "%s: too many open "
1457 "connections, consider increasing the "
1458 "number of nfsd threads\n",
1459 serv->sv_name);
1460 }
1461 /*
1462 * Always select the oldest connection. It's not fair,
1463 * but so is life
1464 */
1465 xprt = list_entry(serv->sv_tempsocks.prev,
1466 struct svc_xprt,
1467 xpt_list);
1468 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1469 svc_xprt_get(xprt);
1470 }
1471 spin_unlock_bh(&serv->sv_lock);
1472
1473 if (xprt) {
1474 svc_xprt_enqueue(xprt);
1475 svc_xprt_put(xprt);
1476 }
1477 }
1478}
1479
1480/*
1481 * Receive the next request on any socket. This code is carefully
1482 * organised not to touch any cachelines in the shared svc_serv
1483 * structure, only cachelines in the local svc_pool.
1484 */
1485int
1486svc_recv(struct svc_rqst *rqstp, long timeout)
1487{
1488 struct svc_xprt *xprt = NULL;
1489 struct svc_serv *serv = rqstp->rq_server;
1490 struct svc_pool *pool = rqstp->rq_pool;
1491 int len, i;
1492 int pages;
1493 struct xdr_buf *arg;
1494 DECLARE_WAITQUEUE(wait, current);
1495
1496 dprintk("svc: server %p waiting for data (to = %ld)\n",
1497 rqstp, timeout);
1498
1499 if (rqstp->rq_xprt)
1500 printk(KERN_ERR
1501 "svc_recv: service %p, transport not NULL!\n",
1502 rqstp);
1503 if (waitqueue_active(&rqstp->rq_wait))
1504 printk(KERN_ERR
1505 "svc_recv: service %p, wait queue active!\n",
1506 rqstp);
1507
1508
1509 /* now allocate needed pages. If we get a failure, sleep briefly */
1510 pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
1511 for (i=0; i < pages ; i++)
1512 while (rqstp->rq_pages[i] == NULL) {
1513 struct page *p = alloc_page(GFP_KERNEL);
1514 if (!p)
1515 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
1516 rqstp->rq_pages[i] = p;
1517 }
1518 rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
1519 BUG_ON(pages >= RPCSVC_MAXPAGES);
1520
1521 /* Make arg->head point to first page and arg->pages point to rest */
1522 arg = &rqstp->rq_arg;
1523 arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
1524 arg->head[0].iov_len = PAGE_SIZE;
1525 arg->pages = rqstp->rq_pages + 1;
1526 arg->page_base = 0;
1527 /* save at least one page for response */
1528 arg->page_len = (pages-2)*PAGE_SIZE;
1529 arg->len = (pages-1)*PAGE_SIZE;
1530 arg->tail[0].iov_len = 0;
1531
1532 try_to_freeze();
1533 cond_resched();
1534 if (signalled())
1535 return -EINTR;
1536
1537 spin_lock_bh(&pool->sp_lock);
1538 xprt = svc_xprt_dequeue(pool);
1539 if (xprt) {
1540 rqstp->rq_xprt = xprt;
1541 svc_xprt_get(xprt);
1542 rqstp->rq_reserved = serv->sv_max_mesg;
1543 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
1544 } else {
1545 /* No data pending. Go to sleep */
1546 svc_thread_enqueue(pool, rqstp);
1547
1548 /*
1549 * We have to be able to interrupt this wait
1550 * to bring down the daemons ...
1551 */
1552 set_current_state(TASK_INTERRUPTIBLE);
1553 add_wait_queue(&rqstp->rq_wait, &wait);
1554 spin_unlock_bh(&pool->sp_lock);
1555
1556 schedule_timeout(timeout);
1557
1558 try_to_freeze();
1559
1560 spin_lock_bh(&pool->sp_lock);
1561 remove_wait_queue(&rqstp->rq_wait, &wait);
1562
1563 xprt = rqstp->rq_xprt;
1564 if (!xprt) {
1565 svc_thread_dequeue(pool, rqstp);
1566 spin_unlock_bh(&pool->sp_lock);
1567 dprintk("svc: server %p, no data yet\n", rqstp);
1568 return signalled()? -EINTR : -EAGAIN;
1569 }
1570 }
1571 spin_unlock_bh(&pool->sp_lock);
1572
1573 len = 0;
1574 if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
1575 dprintk("svc_recv: found XPT_CLOSE\n");
1576 svc_delete_xprt(xprt);
1577 } else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1578 struct svc_xprt *newxpt;
1579 newxpt = xprt->xpt_ops->xpo_accept(xprt);
1580 if (newxpt) {
1581 /*
1582 * We know this module_get will succeed because the
1583 * listener holds a reference too
1584 */
1585 __module_get(newxpt->xpt_class->xcl_owner);
1586 svc_check_conn_limits(xprt->xpt_server);
1587 spin_lock_bh(&serv->sv_lock);
1588 set_bit(XPT_TEMP, &newxpt->xpt_flags);
1589 list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
1590 serv->sv_tmpcnt++;
1591 if (serv->sv_temptimer.function == NULL) {
1592 /* setup timer to age temp sockets */
1593 setup_timer(&serv->sv_temptimer,
1594 svc_age_temp_xprts,
1595 (unsigned long)serv);
1596 mod_timer(&serv->sv_temptimer,
1597 jiffies + svc_conn_age_period * HZ);
1598 }
1599 spin_unlock_bh(&serv->sv_lock);
1600 svc_xprt_received(newxpt);
1601 }
1602 svc_xprt_received(xprt);
1603 } else {
1604 dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
1605 rqstp, pool->sp_id, xprt,
1606 atomic_read(&xprt->xpt_ref.refcount));
1607 rqstp->rq_deferred = svc_deferred_dequeue(xprt);
1608 if (rqstp->rq_deferred) {
1609 svc_xprt_received(xprt);
1610 len = svc_deferred_recv(rqstp);
1611 } else
1612 len = xprt->xpt_ops->xpo_recvfrom(rqstp);
1613 dprintk("svc: got len=%d\n", len);
1614 }
1615
1616 /* No data, incomplete (TCP) read, or accept() */
1617 if (len == 0 || len == -EAGAIN) {
1618 rqstp->rq_res.len = 0;
1619 svc_xprt_release(rqstp);
1620 return -EAGAIN;
1621 }
1622 clear_bit(XPT_OLD, &xprt->xpt_flags);
1623
1624 rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
1625 rqstp->rq_chandle.defer = svc_defer;
1626
1627 if (serv->sv_stats)
1628 serv->sv_stats->netcnt++;
1629 return len;
1630}
1631
1632/*
1633 * Drop request
1634 */
1635void
1636svc_drop(struct svc_rqst *rqstp)
1637{
1638 dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
1639 svc_xprt_release(rqstp);
1640}
1641
1642/*
1643 * Return reply to client.
1644 */
1645int
1646svc_send(struct svc_rqst *rqstp)
1647{
1648 struct svc_xprt *xprt;
1649 int len;
1650 struct xdr_buf *xb;
1651
1652 xprt = rqstp->rq_xprt;
1653 if (!xprt)
1654 return -EFAULT;
1655
1656 /* release the receive skb before sending the reply */
1657 rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
1658
1659 /* calculate over-all length */
1660 xb = & rqstp->rq_res;
1661 xb->len = xb->head[0].iov_len +
1662 xb->page_len +
1663 xb->tail[0].iov_len;
1664
1665 /* Grab mutex to serialize outgoing data. */
1666 mutex_lock(&xprt->xpt_mutex);
1667 if (test_bit(XPT_DEAD, &xprt->xpt_flags))
1668 len = -ENOTCONN;
1669 else
1670 len = xprt->xpt_ops->xpo_sendto(rqstp);
1671 mutex_unlock(&xprt->xpt_mutex);
1672 svc_xprt_release(rqstp);
1673
1674 if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
1675 return 0;
1676 return len;
1677}
1678
1679/*
1680 * Timer function to close old temporary sockets, using
1681 * a mark-and-sweep algorithm.
1682 */
1683static void svc_age_temp_xprts(unsigned long closure)
1684{
1685 struct svc_serv *serv = (struct svc_serv *)closure;
1686 struct svc_xprt *xprt;
1687 struct list_head *le, *next;
1688 LIST_HEAD(to_be_aged);
1689
1690 dprintk("svc_age_temp_xprts\n");
1691
1692 if (!spin_trylock_bh(&serv->sv_lock)) {
1693 /* busy, try again 1 sec later */
1694 dprintk("svc_age_temp_xprts: busy\n");
1695 mod_timer(&serv->sv_temptimer, jiffies + HZ);
1696 return;
1697 }
1698
1699 list_for_each_safe(le, next, &serv->sv_tempsocks) {
1700 xprt = list_entry(le, struct svc_xprt, xpt_list);
1701
1702 /* First time through, just mark it OLD. Second time
1703 * through, close it. */
1704 if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags))
1705 continue;
1706 if (atomic_read(&xprt->xpt_ref.refcount) > 1
1707 || test_bit(XPT_BUSY, &xprt->xpt_flags))
1708 continue;
1709 svc_xprt_get(xprt);
1710 list_move(le, &to_be_aged);
1711 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1712 set_bit(XPT_DETACHED, &xprt->xpt_flags);
1713 }
1714 spin_unlock_bh(&serv->sv_lock);
1715
1716 while (!list_empty(&to_be_aged)) {
1717 le = to_be_aged.next;
1718 /* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
1719 list_del_init(le);
1720 xprt = list_entry(le, struct svc_xprt, xpt_list);
1721
1722 dprintk("queuing xprt %p for closing\n", xprt);
1723
1724 /* a thread will dequeue and close it soon */
1725 svc_xprt_enqueue(xprt);
1726 svc_xprt_put(xprt);
1727 }
1728
1729 mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
1730}
1731
1732/*
1733 * Initialize socket for RPC use and create svc_sock struct 1104 * Initialize socket for RPC use and create svc_sock struct
1734 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF. 1105 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1735 */ 1106 */
@@ -1913,160 +1284,3 @@ static void svc_sock_free(struct svc_xprt *xprt)
1913 sock_release(svsk->sk_sock); 1284 sock_release(svsk->sk_sock);
1914 kfree(svsk); 1285 kfree(svsk);
1915} 1286}
1916
1917/*
1918 * Remove a dead transport
1919 */
1920static void svc_delete_xprt(struct svc_xprt *xprt)
1921{
1922 struct svc_serv *serv = xprt->xpt_server;
1923
1924 dprintk("svc: svc_delete_xprt(%p)\n", xprt);
1925 xprt->xpt_ops->xpo_detach(xprt);
1926
1927 spin_lock_bh(&serv->sv_lock);
1928 if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags))
1929 list_del_init(&xprt->xpt_list);
1930 /*
1931 * We used to delete the transport from whichever list
1932 * it's sk_xprt.xpt_ready node was on, but we don't actually
1933 * need to. This is because the only time we're called
1934 * while still attached to a queue, the queue itself
1935 * is about to be destroyed (in svc_destroy).
1936 */
1937 if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
1938 BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
1939 if (test_bit(XPT_TEMP, &xprt->xpt_flags))
1940 serv->sv_tmpcnt--;
1941 svc_xprt_put(xprt);
1942 }
1943 spin_unlock_bh(&serv->sv_lock);
1944}
1945
1946static void svc_close_xprt(struct svc_xprt *xprt)
1947{
1948 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1949 if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
1950 /* someone else will have to effect the close */
1951 return;
1952
1953 svc_xprt_get(xprt);
1954 svc_delete_xprt(xprt);
1955 clear_bit(XPT_BUSY, &xprt->xpt_flags);
1956 svc_xprt_put(xprt);
1957}
1958
1959void svc_close_all(struct list_head *xprt_list)
1960{
1961 struct svc_xprt *xprt;
1962 struct svc_xprt *tmp;
1963
1964 list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
1965 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1966 if (test_bit(XPT_BUSY, &xprt->xpt_flags)) {
1967 /* Waiting to be processed, but no threads left,
1968 * So just remove it from the waiting list
1969 */
1970 list_del_init(&xprt->xpt_ready);
1971 clear_bit(XPT_BUSY, &xprt->xpt_flags);
1972 }
1973 svc_close_xprt(xprt);
1974 }
1975}
1976
1977/*
1978 * Handle defer and revisit of requests
1979 */
1980
1981static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
1982{
1983 struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle);
1984 struct svc_xprt *xprt = dr->xprt;
1985
1986 if (too_many) {
1987 svc_xprt_put(xprt);
1988 kfree(dr);
1989 return;
1990 }
1991 dprintk("revisit queued\n");
1992 dr->xprt = NULL;
1993 spin_lock(&xprt->xpt_lock);
1994 list_add(&dr->handle.recent, &xprt->xpt_deferred);
1995 spin_unlock(&xprt->xpt_lock);
1996 set_bit(XPT_DEFERRED, &xprt->xpt_flags);
1997 svc_xprt_enqueue(xprt);
1998 svc_xprt_put(xprt);
1999}
2000
2001static struct cache_deferred_req *
2002svc_defer(struct cache_req *req)
2003{
2004 struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
2005 int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
2006 struct svc_deferred_req *dr;
2007
2008 if (rqstp->rq_arg.page_len)
2009 return NULL; /* if more than a page, give up FIXME */
2010 if (rqstp->rq_deferred) {
2011 dr = rqstp->rq_deferred;
2012 rqstp->rq_deferred = NULL;
2013 } else {
2014 int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
2015 /* FIXME maybe discard if size too large */
2016 dr = kmalloc(size, GFP_KERNEL);
2017 if (dr == NULL)
2018 return NULL;
2019
2020 dr->handle.owner = rqstp->rq_server;
2021 dr->prot = rqstp->rq_prot;
2022 memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
2023 dr->addrlen = rqstp->rq_addrlen;
2024 dr->daddr = rqstp->rq_daddr;
2025 dr->argslen = rqstp->rq_arg.len >> 2;
2026 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2);
2027 }
2028 svc_xprt_get(rqstp->rq_xprt);
2029 dr->xprt = rqstp->rq_xprt;
2030
2031 dr->handle.revisit = svc_revisit;
2032 return &dr->handle;
2033}
2034
2035/*
2036 * recv data from a deferred request into an active one
2037 */
2038static int svc_deferred_recv(struct svc_rqst *rqstp)
2039{
2040 struct svc_deferred_req *dr = rqstp->rq_deferred;
2041
2042 rqstp->rq_arg.head[0].iov_base = dr->args;
2043 rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
2044 rqstp->rq_arg.page_len = 0;
2045 rqstp->rq_arg.len = dr->argslen<<2;
2046 rqstp->rq_prot = dr->prot;
2047 memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
2048 rqstp->rq_addrlen = dr->addrlen;
2049 rqstp->rq_daddr = dr->daddr;
2050 rqstp->rq_respages = rqstp->rq_pages;
2051 return dr->argslen<<2;
2052}
2053
2054
2055static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
2056{
2057 struct svc_deferred_req *dr = NULL;
2058
2059 if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
2060 return NULL;
2061 spin_lock(&xprt->xpt_lock);
2062 clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
2063 if (!list_empty(&xprt->xpt_deferred)) {
2064 dr = list_entry(xprt->xpt_deferred.next,
2065 struct svc_deferred_req,
2066 handle.recent);
2067 list_del_init(&dr->handle.recent);
2068 set_bit(XPT_DEFERRED, &xprt->xpt_flags);
2069 }
2070 spin_unlock(&xprt->xpt_lock);
2071 return dr;
2072}