blob: a27905a0ad277a4322d291e333c479794e3383de [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/net/sunrpc/svcsock.c
3 *
4 * These are the RPC server socket internals.
5 *
6 * The server scheduling algorithm does not always distribute the load
7 * evenly when servicing a single client. May need to modify the
8 * svc_sock_enqueue procedure...
9 *
10 * TCP support is largely untested and may be a little slow. The problem
11 * is that we currently do two separate recvfrom's, one for the 4-byte
12 * record length, and the second for the actual record. This could possibly
13 * be improved by always reading a minimum size of around 100 bytes and
14 * tucking any superfluous bytes away in a temporary store. Still, that
15 * leaves write requests out in the rain. An alternative may be to peek at
16 * the first skb in the queue, and if it matches the next TCP sequence
17 * number, to extract the record marker. Yuck.
18 *
19 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
20 */
21
22#include <linux/sched.h>
23#include <linux/errno.h>
24#include <linux/fcntl.h>
25#include <linux/net.h>
26#include <linux/in.h>
27#include <linux/inet.h>
28#include <linux/udp.h>
Andrew Morton91483c42005-08-09 20:20:07 -070029#include <linux/tcp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/unistd.h>
31#include <linux/slab.h>
32#include <linux/netdevice.h>
33#include <linux/skbuff.h>
34#include <net/sock.h>
35#include <net/checksum.h>
36#include <net/ip.h>
Arnaldo Carvalho de Meloc752f072005-08-09 20:08:28 -070037#include <net/tcp_states.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <asm/uaccess.h>
39#include <asm/ioctls.h>
40
41#include <linux/sunrpc/types.h>
42#include <linux/sunrpc/xdr.h>
43#include <linux/sunrpc/svcsock.h>
44#include <linux/sunrpc/stats.h>
45
46/* SMP locking strategy:
47 *
48 * svc_serv->sv_lock protects most stuff for that service.
49 *
50 * Some flags can be set to certain values at any time
51 * providing that certain rules are followed:
52 *
53 * SK_BUSY can be set to 0 at any time.
54 * svc_sock_enqueue must be called afterwards
55 * SK_CONN, SK_DATA, can be set or cleared at any time.
56 * after a set, svc_sock_enqueue must be called.
57 * after a clear, the socket must be read/accepted
58 * if this succeeds, it must be set again.
59 * SK_CLOSE can set at any time. It is never cleared.
60 *
61 */
62
63#define RPCDBG_FACILITY RPCDBG_SVCSOCK
64
65
66static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
67 int *errp, int pmap_reg);
68static void svc_udp_data_ready(struct sock *, int);
69static int svc_udp_recvfrom(struct svc_rqst *);
70static int svc_udp_sendto(struct svc_rqst *);
71
72static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk);
73static int svc_deferred_recv(struct svc_rqst *rqstp);
74static struct cache_deferred_req *svc_defer(struct cache_req *req);
75
76/*
77 * Queue up an idle server thread. Must have serv->sv_lock held.
78 * Note: this is really a stack rather than a queue, so that we only
79 * use as many different threads as we need, and the rest don't polute
80 * the cache.
81 */
82static inline void
83svc_serv_enqueue(struct svc_serv *serv, struct svc_rqst *rqstp)
84{
85 list_add(&rqstp->rq_list, &serv->sv_threads);
86}
87
88/*
89 * Dequeue an nfsd thread. Must have serv->sv_lock held.
90 */
91static inline void
92svc_serv_dequeue(struct svc_serv *serv, struct svc_rqst *rqstp)
93{
94 list_del(&rqstp->rq_list);
95}
96
97/*
98 * Release an skbuff after use
99 */
100static inline void
101svc_release_skb(struct svc_rqst *rqstp)
102{
103 struct sk_buff *skb = rqstp->rq_skbuff;
104 struct svc_deferred_req *dr = rqstp->rq_deferred;
105
106 if (skb) {
107 rqstp->rq_skbuff = NULL;
108
109 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
110 skb_free_datagram(rqstp->rq_sock->sk_sk, skb);
111 }
112 if (dr) {
113 rqstp->rq_deferred = NULL;
114 kfree(dr);
115 }
116}
117
118/*
119 * Any space to write?
120 */
121static inline unsigned long
122svc_sock_wspace(struct svc_sock *svsk)
123{
124 int wspace;
125
126 if (svsk->sk_sock->type == SOCK_STREAM)
127 wspace = sk_stream_wspace(svsk->sk_sk);
128 else
129 wspace = sock_wspace(svsk->sk_sk);
130
131 return wspace;
132}
133
134/*
135 * Queue up a socket with data pending. If there are idle nfsd
136 * processes, wake 'em up.
137 *
138 */
139static void
140svc_sock_enqueue(struct svc_sock *svsk)
141{
142 struct svc_serv *serv = svsk->sk_server;
143 struct svc_rqst *rqstp;
144
145 if (!(svsk->sk_flags &
146 ( (1<<SK_CONN)|(1<<SK_DATA)|(1<<SK_CLOSE)|(1<<SK_DEFERRED)) ))
147 return;
148 if (test_bit(SK_DEAD, &svsk->sk_flags))
149 return;
150
151 spin_lock_bh(&serv->sv_lock);
152
153 if (!list_empty(&serv->sv_threads) &&
154 !list_empty(&serv->sv_sockets))
155 printk(KERN_ERR
156 "svc_sock_enqueue: threads and sockets both waiting??\n");
157
158 if (test_bit(SK_DEAD, &svsk->sk_flags)) {
159 /* Don't enqueue dead sockets */
160 dprintk("svc: socket %p is dead, not enqueued\n", svsk->sk_sk);
161 goto out_unlock;
162 }
163
164 if (test_bit(SK_BUSY, &svsk->sk_flags)) {
165 /* Don't enqueue socket while daemon is receiving */
166 dprintk("svc: socket %p busy, not enqueued\n", svsk->sk_sk);
167 goto out_unlock;
168 }
169
170 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
171 if (((svsk->sk_reserved + serv->sv_bufsz)*2
172 > svc_sock_wspace(svsk))
173 && !test_bit(SK_CLOSE, &svsk->sk_flags)
174 && !test_bit(SK_CONN, &svsk->sk_flags)) {
175 /* Don't enqueue while not enough space for reply */
176 dprintk("svc: socket %p no space, %d*2 > %ld, not enqueued\n",
177 svsk->sk_sk, svsk->sk_reserved+serv->sv_bufsz,
178 svc_sock_wspace(svsk));
179 goto out_unlock;
180 }
181 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
182
183 /* Mark socket as busy. It will remain in this state until the
184 * server has processed all pending data and put the socket back
185 * on the idle list.
186 */
187 set_bit(SK_BUSY, &svsk->sk_flags);
188
189 if (!list_empty(&serv->sv_threads)) {
190 rqstp = list_entry(serv->sv_threads.next,
191 struct svc_rqst,
192 rq_list);
193 dprintk("svc: socket %p served by daemon %p\n",
194 svsk->sk_sk, rqstp);
195 svc_serv_dequeue(serv, rqstp);
196 if (rqstp->rq_sock)
197 printk(KERN_ERR
198 "svc_sock_enqueue: server %p, rq_sock=%p!\n",
199 rqstp, rqstp->rq_sock);
200 rqstp->rq_sock = svsk;
201 svsk->sk_inuse++;
202 rqstp->rq_reserved = serv->sv_bufsz;
203 svsk->sk_reserved += rqstp->rq_reserved;
204 wake_up(&rqstp->rq_wait);
205 } else {
206 dprintk("svc: socket %p put into queue\n", svsk->sk_sk);
207 list_add_tail(&svsk->sk_ready, &serv->sv_sockets);
208 }
209
210out_unlock:
211 spin_unlock_bh(&serv->sv_lock);
212}
213
214/*
215 * Dequeue the first socket. Must be called with the serv->sv_lock held.
216 */
217static inline struct svc_sock *
218svc_sock_dequeue(struct svc_serv *serv)
219{
220 struct svc_sock *svsk;
221
222 if (list_empty(&serv->sv_sockets))
223 return NULL;
224
225 svsk = list_entry(serv->sv_sockets.next,
226 struct svc_sock, sk_ready);
227 list_del_init(&svsk->sk_ready);
228
229 dprintk("svc: socket %p dequeued, inuse=%d\n",
230 svsk->sk_sk, svsk->sk_inuse);
231
232 return svsk;
233}
234
235/*
236 * Having read something from a socket, check whether it
237 * needs to be re-enqueued.
238 * Note: SK_DATA only gets cleared when a read-attempt finds
239 * no (or insufficient) data.
240 */
241static inline void
242svc_sock_received(struct svc_sock *svsk)
243{
244 clear_bit(SK_BUSY, &svsk->sk_flags);
245 svc_sock_enqueue(svsk);
246}
247
248
249/**
250 * svc_reserve - change the space reserved for the reply to a request.
251 * @rqstp: The request in question
252 * @space: new max space to reserve
253 *
254 * Each request reserves some space on the output queue of the socket
255 * to make sure the reply fits. This function reduces that reserved
256 * space to be the amount of space used already, plus @space.
257 *
258 */
259void svc_reserve(struct svc_rqst *rqstp, int space)
260{
261 space += rqstp->rq_res.head[0].iov_len;
262
263 if (space < rqstp->rq_reserved) {
264 struct svc_sock *svsk = rqstp->rq_sock;
265 spin_lock_bh(&svsk->sk_server->sv_lock);
266 svsk->sk_reserved -= (rqstp->rq_reserved - space);
267 rqstp->rq_reserved = space;
268 spin_unlock_bh(&svsk->sk_server->sv_lock);
269
270 svc_sock_enqueue(svsk);
271 }
272}
273
274/*
275 * Release a socket after use.
276 */
277static inline void
278svc_sock_put(struct svc_sock *svsk)
279{
280 struct svc_serv *serv = svsk->sk_server;
281
282 spin_lock_bh(&serv->sv_lock);
283 if (!--(svsk->sk_inuse) && test_bit(SK_DEAD, &svsk->sk_flags)) {
284 spin_unlock_bh(&serv->sv_lock);
285 dprintk("svc: releasing dead socket\n");
286 sock_release(svsk->sk_sock);
287 kfree(svsk);
288 }
289 else
290 spin_unlock_bh(&serv->sv_lock);
291}
292
293static void
294svc_sock_release(struct svc_rqst *rqstp)
295{
296 struct svc_sock *svsk = rqstp->rq_sock;
297
298 svc_release_skb(rqstp);
299
300 svc_free_allpages(rqstp);
301 rqstp->rq_res.page_len = 0;
302 rqstp->rq_res.page_base = 0;
303
304
305 /* Reset response buffer and release
306 * the reservation.
307 * But first, check that enough space was reserved
308 * for the reply, otherwise we have a bug!
309 */
310 if ((rqstp->rq_res.len) > rqstp->rq_reserved)
311 printk(KERN_ERR "RPC request reserved %d but used %d\n",
312 rqstp->rq_reserved,
313 rqstp->rq_res.len);
314
315 rqstp->rq_res.head[0].iov_len = 0;
316 svc_reserve(rqstp, 0);
317 rqstp->rq_sock = NULL;
318
319 svc_sock_put(svsk);
320}
321
322/*
323 * External function to wake up a server waiting for data
324 */
325void
326svc_wake_up(struct svc_serv *serv)
327{
328 struct svc_rqst *rqstp;
329
330 spin_lock_bh(&serv->sv_lock);
331 if (!list_empty(&serv->sv_threads)) {
332 rqstp = list_entry(serv->sv_threads.next,
333 struct svc_rqst,
334 rq_list);
335 dprintk("svc: daemon %p woken up.\n", rqstp);
336 /*
337 svc_serv_dequeue(serv, rqstp);
338 rqstp->rq_sock = NULL;
339 */
340 wake_up(&rqstp->rq_wait);
341 }
342 spin_unlock_bh(&serv->sv_lock);
343}
344
345/*
346 * Generic sendto routine
347 */
348static int
349svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
350{
351 struct svc_sock *svsk = rqstp->rq_sock;
352 struct socket *sock = svsk->sk_sock;
353 int slen;
354 char buffer[CMSG_SPACE(sizeof(struct in_pktinfo))];
355 struct cmsghdr *cmh = (struct cmsghdr *)buffer;
356 struct in_pktinfo *pki = (struct in_pktinfo *)CMSG_DATA(cmh);
357 int len = 0;
358 int result;
359 int size;
360 struct page **ppage = xdr->pages;
361 size_t base = xdr->page_base;
362 unsigned int pglen = xdr->page_len;
363 unsigned int flags = MSG_MORE;
364
365 slen = xdr->len;
366
367 if (rqstp->rq_prot == IPPROTO_UDP) {
368 /* set the source and destination */
369 struct msghdr msg;
370 msg.msg_name = &rqstp->rq_addr;
371 msg.msg_namelen = sizeof(rqstp->rq_addr);
372 msg.msg_iov = NULL;
373 msg.msg_iovlen = 0;
374 msg.msg_flags = MSG_MORE;
375
376 msg.msg_control = cmh;
377 msg.msg_controllen = sizeof(buffer);
378 cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
379 cmh->cmsg_level = SOL_IP;
380 cmh->cmsg_type = IP_PKTINFO;
381 pki->ipi_ifindex = 0;
382 pki->ipi_spec_dst.s_addr = rqstp->rq_daddr;
383
384 if (sock_sendmsg(sock, &msg, 0) < 0)
385 goto out;
386 }
387
388 /* send head */
389 if (slen == xdr->head[0].iov_len)
390 flags = 0;
391 len = sock->ops->sendpage(sock, rqstp->rq_respages[0], 0, xdr->head[0].iov_len, flags);
392 if (len != xdr->head[0].iov_len)
393 goto out;
394 slen -= xdr->head[0].iov_len;
395 if (slen == 0)
396 goto out;
397
398 /* send page data */
399 size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
400 while (pglen > 0) {
401 if (slen == size)
402 flags = 0;
403 result = sock->ops->sendpage(sock, *ppage, base, size, flags);
404 if (result > 0)
405 len += result;
406 if (result != size)
407 goto out;
408 slen -= size;
409 pglen -= size;
410 size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
411 base = 0;
412 ppage++;
413 }
414 /* send tail */
415 if (xdr->tail[0].iov_len) {
416 result = sock->ops->sendpage(sock, rqstp->rq_respages[rqstp->rq_restailpage],
417 ((unsigned long)xdr->tail[0].iov_base)& (PAGE_SIZE-1),
418 xdr->tail[0].iov_len, 0);
419
420 if (result > 0)
421 len += result;
422 }
423out:
424 dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %x)\n",
425 rqstp->rq_sock, xdr->head[0].iov_base, xdr->head[0].iov_len, xdr->len, len,
426 rqstp->rq_addr.sin_addr.s_addr);
427
428 return len;
429}
430
431/*
432 * Check input queue length
433 */
434static int
435svc_recv_available(struct svc_sock *svsk)
436{
437 mm_segment_t oldfs;
438 struct socket *sock = svsk->sk_sock;
439 int avail, err;
440
441 oldfs = get_fs(); set_fs(KERNEL_DS);
442 err = sock->ops->ioctl(sock, TIOCINQ, (unsigned long) &avail);
443 set_fs(oldfs);
444
445 return (err >= 0)? avail : err;
446}
447
448/*
449 * Generic recvfrom routine.
450 */
451static int
452svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen)
453{
454 struct msghdr msg;
455 struct socket *sock;
456 int len, alen;
457
458 rqstp->rq_addrlen = sizeof(rqstp->rq_addr);
459 sock = rqstp->rq_sock->sk_sock;
460
461 msg.msg_name = &rqstp->rq_addr;
462 msg.msg_namelen = sizeof(rqstp->rq_addr);
463 msg.msg_control = NULL;
464 msg.msg_controllen = 0;
465
466 msg.msg_flags = MSG_DONTWAIT;
467
468 len = kernel_recvmsg(sock, &msg, iov, nr, buflen, MSG_DONTWAIT);
469
470 /* sock_recvmsg doesn't fill in the name/namelen, so we must..
471 * possibly we should cache this in the svc_sock structure
472 * at accept time. FIXME
473 */
474 alen = sizeof(rqstp->rq_addr);
475 sock->ops->getname(sock, (struct sockaddr *)&rqstp->rq_addr, &alen, 1);
476
477 dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
478 rqstp->rq_sock, iov[0].iov_base, iov[0].iov_len, len);
479
480 return len;
481}
482
483/*
484 * Set socket snd and rcv buffer lengths
485 */
486static inline void
487svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv)
488{
489#if 0
490 mm_segment_t oldfs;
491 oldfs = get_fs(); set_fs(KERNEL_DS);
492 sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
493 (char*)&snd, sizeof(snd));
494 sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
495 (char*)&rcv, sizeof(rcv));
496#else
497 /* sock_setsockopt limits use to sysctl_?mem_max,
498 * which isn't acceptable. Until that is made conditional
499 * on not having CAP_SYS_RESOURCE or similar, we go direct...
500 * DaveM said I could!
501 */
502 lock_sock(sock->sk);
503 sock->sk->sk_sndbuf = snd * 2;
504 sock->sk->sk_rcvbuf = rcv * 2;
505 sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
506 release_sock(sock->sk);
507#endif
508}
509/*
510 * INET callback when data has been received on the socket.
511 */
512static void
513svc_udp_data_ready(struct sock *sk, int count)
514{
Neil Brown939bb7e2005-09-13 01:25:39 -0700515 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516
Neil Brown939bb7e2005-09-13 01:25:39 -0700517 if (svsk) {
518 dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
519 svsk, sk, count, test_bit(SK_BUSY, &svsk->sk_flags));
520 set_bit(SK_DATA, &svsk->sk_flags);
521 svc_sock_enqueue(svsk);
522 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
524 wake_up_interruptible(sk->sk_sleep);
525}
526
527/*
528 * INET callback when space is newly available on the socket.
529 */
530static void
531svc_write_space(struct sock *sk)
532{
533 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
534
535 if (svsk) {
536 dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
537 svsk, sk, test_bit(SK_BUSY, &svsk->sk_flags));
538 svc_sock_enqueue(svsk);
539 }
540
541 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) {
Neil Brown939bb7e2005-09-13 01:25:39 -0700542 dprintk("RPC svc_write_space: someone sleeping on %p\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 svsk);
544 wake_up_interruptible(sk->sk_sleep);
545 }
546}
547
548/*
549 * Receive a datagram from a UDP socket.
550 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551static int
552svc_udp_recvfrom(struct svc_rqst *rqstp)
553{
554 struct svc_sock *svsk = rqstp->rq_sock;
555 struct svc_serv *serv = svsk->sk_server;
556 struct sk_buff *skb;
557 int err, len;
558
559 if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags))
560 /* udp sockets need large rcvbuf as all pending
561 * requests are still in that buffer. sndbuf must
562 * also be large enough that there is enough space
563 * for one reply per thread.
564 */
565 svc_sock_setbufsize(svsk->sk_sock,
566 (serv->sv_nrthreads+3) * serv->sv_bufsz,
567 (serv->sv_nrthreads+3) * serv->sv_bufsz);
568
569 if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
570 svc_sock_received(svsk);
571 return svc_deferred_recv(rqstp);
572 }
573
574 clear_bit(SK_DATA, &svsk->sk_flags);
575 while ((skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err)) == NULL) {
576 if (err == -EAGAIN) {
577 svc_sock_received(svsk);
578 return err;
579 }
580 /* possibly an icmp error */
581 dprintk("svc: recvfrom returned error %d\n", -err);
582 }
Patrick McHardya61bbcf2005-08-14 17:24:31 -0700583 if (skb->tstamp.off_sec == 0) {
584 struct timeval tv;
585
586 tv.tv_sec = xtime.tv_sec;
Andrew Morton4bcde032005-10-26 01:59:03 -0700587 tv.tv_usec = xtime.tv_nsec / NSEC_PER_USEC;
Patrick McHardya61bbcf2005-08-14 17:24:31 -0700588 skb_set_timestamp(skb, &tv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 /* Don't enable netstamp, sunrpc doesn't
590 need that much accuracy */
591 }
Patrick McHardya61bbcf2005-08-14 17:24:31 -0700592 skb_get_timestamp(skb, &svsk->sk_sk->sk_stamp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 set_bit(SK_DATA, &svsk->sk_flags); /* there may be more data... */
594
595 /*
596 * Maybe more packets - kick another thread ASAP.
597 */
598 svc_sock_received(svsk);
599
600 len = skb->len - sizeof(struct udphdr);
601 rqstp->rq_arg.len = len;
602
603 rqstp->rq_prot = IPPROTO_UDP;
604
605 /* Get sender address */
606 rqstp->rq_addr.sin_family = AF_INET;
607 rqstp->rq_addr.sin_port = skb->h.uh->source;
608 rqstp->rq_addr.sin_addr.s_addr = skb->nh.iph->saddr;
609 rqstp->rq_daddr = skb->nh.iph->daddr;
610
611 if (skb_is_nonlinear(skb)) {
612 /* we have to copy */
613 local_bh_disable();
614 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
615 local_bh_enable();
616 /* checksum error */
617 skb_free_datagram(svsk->sk_sk, skb);
618 return 0;
619 }
620 local_bh_enable();
621 skb_free_datagram(svsk->sk_sk, skb);
622 } else {
623 /* we can use it in-place */
624 rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr);
625 rqstp->rq_arg.head[0].iov_len = len;
Herbert Xufb286bb2005-11-10 13:01:24 -0800626 if (skb_checksum_complete(skb)) {
627 skb_free_datagram(svsk->sk_sk, skb);
628 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 }
630 rqstp->rq_skbuff = skb;
631 }
632
633 rqstp->rq_arg.page_base = 0;
634 if (len <= rqstp->rq_arg.head[0].iov_len) {
635 rqstp->rq_arg.head[0].iov_len = len;
636 rqstp->rq_arg.page_len = 0;
637 } else {
638 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
639 rqstp->rq_argused += (rqstp->rq_arg.page_len + PAGE_SIZE - 1)/ PAGE_SIZE;
640 }
641
642 if (serv->sv_stats)
643 serv->sv_stats->netudpcnt++;
644
645 return len;
646}
647
648static int
649svc_udp_sendto(struct svc_rqst *rqstp)
650{
651 int error;
652
653 error = svc_sendto(rqstp, &rqstp->rq_res);
654 if (error == -ECONNREFUSED)
655 /* ICMP error on earlier request. */
656 error = svc_sendto(rqstp, &rqstp->rq_res);
657
658 return error;
659}
660
661static void
662svc_udp_init(struct svc_sock *svsk)
663{
664 svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
665 svsk->sk_sk->sk_write_space = svc_write_space;
666 svsk->sk_recvfrom = svc_udp_recvfrom;
667 svsk->sk_sendto = svc_udp_sendto;
668
669 /* initialise setting must have enough space to
670 * receive and respond to one request.
671 * svc_udp_recvfrom will re-adjust if necessary
672 */
673 svc_sock_setbufsize(svsk->sk_sock,
674 3 * svsk->sk_server->sv_bufsz,
675 3 * svsk->sk_server->sv_bufsz);
676
677 set_bit(SK_DATA, &svsk->sk_flags); /* might have come in before data_ready set up */
678 set_bit(SK_CHNGBUF, &svsk->sk_flags);
679}
680
681/*
682 * A data_ready event on a listening socket means there's a connection
683 * pending. Do not use state_change as a substitute for it.
684 */
685static void
686svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
687{
Neil Brown939bb7e2005-09-13 01:25:39 -0700688 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
690 dprintk("svc: socket %p TCP (listen) state change %d\n",
Neil Brown939bb7e2005-09-13 01:25:39 -0700691 sk, sk->sk_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692
Neil Brown939bb7e2005-09-13 01:25:39 -0700693 /*
694 * This callback may called twice when a new connection
695 * is established as a child socket inherits everything
696 * from a parent LISTEN socket.
697 * 1) data_ready method of the parent socket will be called
698 * when one of child sockets become ESTABLISHED.
699 * 2) data_ready method of the child socket may be called
700 * when it receives data before the socket is accepted.
701 * In case of 2, we should ignore it silently.
702 */
703 if (sk->sk_state == TCP_LISTEN) {
704 if (svsk) {
705 set_bit(SK_CONN, &svsk->sk_flags);
706 svc_sock_enqueue(svsk);
707 } else
708 printk("svc: socket %p: no user data\n", sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 }
Neil Brown939bb7e2005-09-13 01:25:39 -0700710
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
712 wake_up_interruptible_all(sk->sk_sleep);
713}
714
715/*
716 * A state change on a connected socket means it's dying or dead.
717 */
718static void
719svc_tcp_state_change(struct sock *sk)
720{
Neil Brown939bb7e2005-09-13 01:25:39 -0700721 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
723 dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
Neil Brown939bb7e2005-09-13 01:25:39 -0700724 sk, sk->sk_state, sk->sk_user_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725
Neil Brown939bb7e2005-09-13 01:25:39 -0700726 if (!svsk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 printk("svc: socket %p: no user data\n", sk);
Neil Brown939bb7e2005-09-13 01:25:39 -0700728 else {
729 set_bit(SK_CLOSE, &svsk->sk_flags);
730 svc_sock_enqueue(svsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
733 wake_up_interruptible_all(sk->sk_sleep);
734}
735
736static void
737svc_tcp_data_ready(struct sock *sk, int count)
738{
Neil Brown939bb7e2005-09-13 01:25:39 -0700739 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740
741 dprintk("svc: socket %p TCP data ready (svsk %p)\n",
Neil Brown939bb7e2005-09-13 01:25:39 -0700742 sk, sk->sk_user_data);
743 if (svsk) {
744 set_bit(SK_DATA, &svsk->sk_flags);
745 svc_sock_enqueue(svsk);
746 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
748 wake_up_interruptible(sk->sk_sleep);
749}
750
751/*
752 * Accept a TCP connection
753 */
754static void
755svc_tcp_accept(struct svc_sock *svsk)
756{
757 struct sockaddr_in sin;
758 struct svc_serv *serv = svsk->sk_server;
759 struct socket *sock = svsk->sk_sock;
760 struct socket *newsock;
Eric Dumazet90ddc4f2005-12-22 12:49:22 -0800761 const struct proto_ops *ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 struct svc_sock *newsvsk;
763 int err, slen;
764
765 dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
766 if (!sock)
767 return;
768
769 err = sock_create_lite(PF_INET, SOCK_STREAM, IPPROTO_TCP, &newsock);
770 if (err) {
771 if (err == -ENOMEM)
772 printk(KERN_WARNING "%s: no more sockets!\n",
773 serv->sv_name);
774 return;
775 }
776
777 dprintk("svc: tcp_accept %p allocated\n", newsock);
778 newsock->ops = ops = sock->ops;
779
780 clear_bit(SK_CONN, &svsk->sk_flags);
781 if ((err = ops->accept(sock, newsock, O_NONBLOCK)) < 0) {
782 if (err != -EAGAIN && net_ratelimit())
783 printk(KERN_WARNING "%s: accept failed (err %d)!\n",
784 serv->sv_name, -err);
785 goto failed; /* aborted connection or whatever */
786 }
787 set_bit(SK_CONN, &svsk->sk_flags);
788 svc_sock_enqueue(svsk);
789
790 slen = sizeof(sin);
791 err = ops->getname(newsock, (struct sockaddr *) &sin, &slen, 1);
792 if (err < 0) {
793 if (net_ratelimit())
794 printk(KERN_WARNING "%s: peername failed (err %d)!\n",
795 serv->sv_name, -err);
796 goto failed; /* aborted connection or whatever */
797 }
798
799 /* Ideally, we would want to reject connections from unauthorized
800 * hosts here, but when we get encription, the IP of the host won't
801 * tell us anything. For now just warn about unpriv connections.
802 */
803 if (ntohs(sin.sin_port) >= 1024) {
804 dprintk(KERN_WARNING
805 "%s: connect from unprivileged port: %u.%u.%u.%u:%d\n",
806 serv->sv_name,
807 NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
808 }
809
810 dprintk("%s: connect from %u.%u.%u.%u:%04x\n", serv->sv_name,
811 NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
812
813 /* make sure that a write doesn't block forever when
814 * low on memory
815 */
816 newsock->sk->sk_sndtimeo = HZ*30;
817
818 if (!(newsvsk = svc_setup_socket(serv, newsock, &err, 0)))
819 goto failed;
820
821
822 /* make sure that we don't have too many active connections.
823 * If we have, something must be dropped.
824 *
825 * There's no point in trying to do random drop here for
826 * DoS prevention. The NFS clients does 1 reconnect in 15
827 * seconds. An attacker can easily beat that.
828 *
829 * The only somewhat efficient mechanism would be if drop
830 * old connections from the same IP first. But right now
831 * we don't even record the client IP in svc_sock.
832 */
833 if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
834 struct svc_sock *svsk = NULL;
835 spin_lock_bh(&serv->sv_lock);
836 if (!list_empty(&serv->sv_tempsocks)) {
837 if (net_ratelimit()) {
838 /* Try to help the admin */
839 printk(KERN_NOTICE "%s: too many open TCP "
840 "sockets, consider increasing the "
841 "number of nfsd threads\n",
842 serv->sv_name);
843 printk(KERN_NOTICE "%s: last TCP connect from "
844 "%u.%u.%u.%u:%d\n",
845 serv->sv_name,
846 NIPQUAD(sin.sin_addr.s_addr),
847 ntohs(sin.sin_port));
848 }
849 /*
850 * Always select the oldest socket. It's not fair,
851 * but so is life
852 */
853 svsk = list_entry(serv->sv_tempsocks.prev,
854 struct svc_sock,
855 sk_list);
856 set_bit(SK_CLOSE, &svsk->sk_flags);
857 svsk->sk_inuse ++;
858 }
859 spin_unlock_bh(&serv->sv_lock);
860
861 if (svsk) {
862 svc_sock_enqueue(svsk);
863 svc_sock_put(svsk);
864 }
865
866 }
867
868 if (serv->sv_stats)
869 serv->sv_stats->nettcpconn++;
870
871 return;
872
873failed:
874 sock_release(newsock);
875 return;
876}
877
878/*
879 * Receive data from a TCP socket.
880 */
881static int
882svc_tcp_recvfrom(struct svc_rqst *rqstp)
883{
884 struct svc_sock *svsk = rqstp->rq_sock;
885 struct svc_serv *serv = svsk->sk_server;
886 int len;
887 struct kvec vec[RPCSVC_MAXPAGES];
888 int pnum, vlen;
889
890 dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
891 svsk, test_bit(SK_DATA, &svsk->sk_flags),
892 test_bit(SK_CONN, &svsk->sk_flags),
893 test_bit(SK_CLOSE, &svsk->sk_flags));
894
895 if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
896 svc_sock_received(svsk);
897 return svc_deferred_recv(rqstp);
898 }
899
900 if (test_bit(SK_CLOSE, &svsk->sk_flags)) {
901 svc_delete_socket(svsk);
902 return 0;
903 }
904
905 if (test_bit(SK_CONN, &svsk->sk_flags)) {
906 svc_tcp_accept(svsk);
907 svc_sock_received(svsk);
908 return 0;
909 }
910
911 if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags))
912 /* sndbuf needs to have room for one request
913 * per thread, otherwise we can stall even when the
914 * network isn't a bottleneck.
915 * rcvbuf just needs to be able to hold a few requests.
916 * Normally they will be removed from the queue
917 * as soon a a complete request arrives.
918 */
919 svc_sock_setbufsize(svsk->sk_sock,
920 (serv->sv_nrthreads+3) * serv->sv_bufsz,
921 3 * serv->sv_bufsz);
922
923 clear_bit(SK_DATA, &svsk->sk_flags);
924
925 /* Receive data. If we haven't got the record length yet, get
926 * the next four bytes. Otherwise try to gobble up as much as
927 * possible up to the complete record length.
928 */
929 if (svsk->sk_tcplen < 4) {
930 unsigned long want = 4 - svsk->sk_tcplen;
931 struct kvec iov;
932
933 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
934 iov.iov_len = want;
935 if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
936 goto error;
937 svsk->sk_tcplen += len;
938
939 if (len < want) {
940 dprintk("svc: short recvfrom while reading record length (%d of %lu)\n",
941 len, want);
942 svc_sock_received(svsk);
943 return -EAGAIN; /* record header not complete */
944 }
945
946 svsk->sk_reclen = ntohl(svsk->sk_reclen);
947 if (!(svsk->sk_reclen & 0x80000000)) {
948 /* FIXME: technically, a record can be fragmented,
949 * and non-terminal fragments will not have the top
950 * bit set in the fragment length header.
951 * But apparently no known nfs clients send fragmented
952 * records. */
953 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx (non-terminal)\n",
954 (unsigned long) svsk->sk_reclen);
955 goto err_delete;
956 }
957 svsk->sk_reclen &= 0x7fffffff;
958 dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
959 if (svsk->sk_reclen > serv->sv_bufsz) {
960 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx (large)\n",
961 (unsigned long) svsk->sk_reclen);
962 goto err_delete;
963 }
964 }
965
966 /* Check whether enough data is available */
967 len = svc_recv_available(svsk);
968 if (len < 0)
969 goto error;
970
971 if (len < svsk->sk_reclen) {
972 dprintk("svc: incomplete TCP record (%d of %d)\n",
973 len, svsk->sk_reclen);
974 svc_sock_received(svsk);
975 return -EAGAIN; /* record not complete */
976 }
977 len = svsk->sk_reclen;
978 set_bit(SK_DATA, &svsk->sk_flags);
979
980 vec[0] = rqstp->rq_arg.head[0];
981 vlen = PAGE_SIZE;
982 pnum = 1;
983 while (vlen < len) {
984 vec[pnum].iov_base = page_address(rqstp->rq_argpages[rqstp->rq_argused++]);
985 vec[pnum].iov_len = PAGE_SIZE;
986 pnum++;
987 vlen += PAGE_SIZE;
988 }
989
990 /* Now receive data */
991 len = svc_recvfrom(rqstp, vec, pnum, len);
992 if (len < 0)
993 goto error;
994
995 dprintk("svc: TCP complete record (%d bytes)\n", len);
996 rqstp->rq_arg.len = len;
997 rqstp->rq_arg.page_base = 0;
998 if (len <= rqstp->rq_arg.head[0].iov_len) {
999 rqstp->rq_arg.head[0].iov_len = len;
1000 rqstp->rq_arg.page_len = 0;
1001 } else {
1002 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
1003 }
1004
1005 rqstp->rq_skbuff = NULL;
1006 rqstp->rq_prot = IPPROTO_TCP;
1007
1008 /* Reset TCP read info */
1009 svsk->sk_reclen = 0;
1010 svsk->sk_tcplen = 0;
1011
1012 svc_sock_received(svsk);
1013 if (serv->sv_stats)
1014 serv->sv_stats->nettcpcnt++;
1015
1016 return len;
1017
1018 err_delete:
1019 svc_delete_socket(svsk);
1020 return -EAGAIN;
1021
1022 error:
1023 if (len == -EAGAIN) {
1024 dprintk("RPC: TCP recvfrom got EAGAIN\n");
1025 svc_sock_received(svsk);
1026 } else {
1027 printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1028 svsk->sk_server->sv_name, -len);
Olaf Kirch93fbf1a2006-01-06 00:19:56 -08001029 goto err_delete;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030 }
1031
1032 return len;
1033}
1034
1035/*
1036 * Send out data on TCP socket.
1037 */
1038static int
1039svc_tcp_sendto(struct svc_rqst *rqstp)
1040{
1041 struct xdr_buf *xbufp = &rqstp->rq_res;
1042 int sent;
1043 u32 reclen;
1044
1045 /* Set up the first element of the reply kvec.
1046 * Any other kvecs that may be in use have been taken
1047 * care of by the server implementation itself.
1048 */
1049 reclen = htonl(0x80000000|((xbufp->len ) - 4));
1050 memcpy(xbufp->head[0].iov_base, &reclen, 4);
1051
1052 if (test_bit(SK_DEAD, &rqstp->rq_sock->sk_flags))
1053 return -ENOTCONN;
1054
1055 sent = svc_sendto(rqstp, &rqstp->rq_res);
1056 if (sent != xbufp->len) {
1057 printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n",
1058 rqstp->rq_sock->sk_server->sv_name,
1059 (sent<0)?"got error":"sent only",
1060 sent, xbufp->len);
1061 svc_delete_socket(rqstp->rq_sock);
1062 sent = -EAGAIN;
1063 }
1064 return sent;
1065}
1066
1067static void
1068svc_tcp_init(struct svc_sock *svsk)
1069{
1070 struct sock *sk = svsk->sk_sk;
1071 struct tcp_sock *tp = tcp_sk(sk);
1072
1073 svsk->sk_recvfrom = svc_tcp_recvfrom;
1074 svsk->sk_sendto = svc_tcp_sendto;
1075
1076 if (sk->sk_state == TCP_LISTEN) {
1077 dprintk("setting up TCP socket for listening\n");
1078 sk->sk_data_ready = svc_tcp_listen_data_ready;
1079 set_bit(SK_CONN, &svsk->sk_flags);
1080 } else {
1081 dprintk("setting up TCP socket for reading\n");
1082 sk->sk_state_change = svc_tcp_state_change;
1083 sk->sk_data_ready = svc_tcp_data_ready;
1084 sk->sk_write_space = svc_write_space;
1085
1086 svsk->sk_reclen = 0;
1087 svsk->sk_tcplen = 0;
1088
1089 tp->nonagle = 1; /* disable Nagle's algorithm */
1090
1091 /* initialise setting must have enough space to
1092 * receive and respond to one request.
1093 * svc_tcp_recvfrom will re-adjust if necessary
1094 */
1095 svc_sock_setbufsize(svsk->sk_sock,
1096 3 * svsk->sk_server->sv_bufsz,
1097 3 * svsk->sk_server->sv_bufsz);
1098
1099 set_bit(SK_CHNGBUF, &svsk->sk_flags);
1100 set_bit(SK_DATA, &svsk->sk_flags);
1101 if (sk->sk_state != TCP_ESTABLISHED)
1102 set_bit(SK_CLOSE, &svsk->sk_flags);
1103 }
1104}
1105
1106void
1107svc_sock_update_bufs(struct svc_serv *serv)
1108{
1109 /*
1110 * The number of server threads has changed. Update
1111 * rcvbuf and sndbuf accordingly on all sockets
1112 */
1113 struct list_head *le;
1114
1115 spin_lock_bh(&serv->sv_lock);
1116 list_for_each(le, &serv->sv_permsocks) {
1117 struct svc_sock *svsk =
1118 list_entry(le, struct svc_sock, sk_list);
1119 set_bit(SK_CHNGBUF, &svsk->sk_flags);
1120 }
1121 list_for_each(le, &serv->sv_tempsocks) {
1122 struct svc_sock *svsk =
1123 list_entry(le, struct svc_sock, sk_list);
1124 set_bit(SK_CHNGBUF, &svsk->sk_flags);
1125 }
1126 spin_unlock_bh(&serv->sv_lock);
1127}
1128
1129/*
1130 * Receive the next request on any socket.
1131 */
1132int
1133svc_recv(struct svc_serv *serv, struct svc_rqst *rqstp, long timeout)
1134{
1135 struct svc_sock *svsk =NULL;
1136 int len;
1137 int pages;
1138 struct xdr_buf *arg;
1139 DECLARE_WAITQUEUE(wait, current);
1140
1141 dprintk("svc: server %p waiting for data (to = %ld)\n",
1142 rqstp, timeout);
1143
1144 if (rqstp->rq_sock)
1145 printk(KERN_ERR
1146 "svc_recv: service %p, socket not NULL!\n",
1147 rqstp);
1148 if (waitqueue_active(&rqstp->rq_wait))
1149 printk(KERN_ERR
1150 "svc_recv: service %p, wait queue active!\n",
1151 rqstp);
1152
1153 /* Initialize the buffers */
1154 /* first reclaim pages that were moved to response list */
1155 svc_pushback_allpages(rqstp);
1156
1157 /* now allocate needed pages. If we get a failure, sleep briefly */
1158 pages = 2 + (serv->sv_bufsz + PAGE_SIZE -1) / PAGE_SIZE;
1159 while (rqstp->rq_arghi < pages) {
1160 struct page *p = alloc_page(GFP_KERNEL);
1161 if (!p) {
Nishanth Aravamudan121caf52005-09-12 14:15:34 -07001162 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 continue;
1164 }
1165 rqstp->rq_argpages[rqstp->rq_arghi++] = p;
1166 }
1167
1168 /* Make arg->head point to first page and arg->pages point to rest */
1169 arg = &rqstp->rq_arg;
1170 arg->head[0].iov_base = page_address(rqstp->rq_argpages[0]);
1171 arg->head[0].iov_len = PAGE_SIZE;
1172 rqstp->rq_argused = 1;
1173 arg->pages = rqstp->rq_argpages + 1;
1174 arg->page_base = 0;
1175 /* save at least one page for response */
1176 arg->page_len = (pages-2)*PAGE_SIZE;
1177 arg->len = (pages-1)*PAGE_SIZE;
1178 arg->tail[0].iov_len = 0;
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001179
1180 try_to_freeze();
NeilBrown1887b932005-11-15 00:09:10 -08001181 cond_resched();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001182 if (signalled())
1183 return -EINTR;
1184
1185 spin_lock_bh(&serv->sv_lock);
1186 if (!list_empty(&serv->sv_tempsocks)) {
1187 svsk = list_entry(serv->sv_tempsocks.next,
1188 struct svc_sock, sk_list);
1189 /* apparently the "standard" is that clients close
1190 * idle connections after 5 minutes, servers after
1191 * 6 minutes
1192 * http://www.connectathon.org/talks96/nfstcp.pdf
1193 */
1194 if (get_seconds() - svsk->sk_lastrecv < 6*60
1195 || test_bit(SK_BUSY, &svsk->sk_flags))
1196 svsk = NULL;
1197 }
1198 if (svsk) {
1199 set_bit(SK_BUSY, &svsk->sk_flags);
1200 set_bit(SK_CLOSE, &svsk->sk_flags);
1201 rqstp->rq_sock = svsk;
1202 svsk->sk_inuse++;
1203 } else if ((svsk = svc_sock_dequeue(serv)) != NULL) {
1204 rqstp->rq_sock = svsk;
1205 svsk->sk_inuse++;
1206 rqstp->rq_reserved = serv->sv_bufsz;
1207 svsk->sk_reserved += rqstp->rq_reserved;
1208 } else {
1209 /* No data pending. Go to sleep */
1210 svc_serv_enqueue(serv, rqstp);
1211
1212 /*
1213 * We have to be able to interrupt this wait
1214 * to bring down the daemons ...
1215 */
1216 set_current_state(TASK_INTERRUPTIBLE);
1217 add_wait_queue(&rqstp->rq_wait, &wait);
1218 spin_unlock_bh(&serv->sv_lock);
1219
1220 schedule_timeout(timeout);
1221
Christoph Lameter3e1d1d22005-06-24 23:13:50 -07001222 try_to_freeze();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223
1224 spin_lock_bh(&serv->sv_lock);
1225 remove_wait_queue(&rqstp->rq_wait, &wait);
1226
1227 if (!(svsk = rqstp->rq_sock)) {
1228 svc_serv_dequeue(serv, rqstp);
1229 spin_unlock_bh(&serv->sv_lock);
1230 dprintk("svc: server %p, no data yet\n", rqstp);
1231 return signalled()? -EINTR : -EAGAIN;
1232 }
1233 }
1234 spin_unlock_bh(&serv->sv_lock);
1235
1236 dprintk("svc: server %p, socket %p, inuse=%d\n",
1237 rqstp, svsk, svsk->sk_inuse);
1238 len = svsk->sk_recvfrom(rqstp);
1239 dprintk("svc: got len=%d\n", len);
1240
1241 /* No data, incomplete (TCP) read, or accept() */
1242 if (len == 0 || len == -EAGAIN) {
1243 rqstp->rq_res.len = 0;
1244 svc_sock_release(rqstp);
1245 return -EAGAIN;
1246 }
1247 svsk->sk_lastrecv = get_seconds();
1248 if (test_bit(SK_TEMP, &svsk->sk_flags)) {
1249 /* push active sockets to end of list */
1250 spin_lock_bh(&serv->sv_lock);
1251 if (!list_empty(&svsk->sk_list))
1252 list_move_tail(&svsk->sk_list, &serv->sv_tempsocks);
1253 spin_unlock_bh(&serv->sv_lock);
1254 }
1255
1256 rqstp->rq_secure = ntohs(rqstp->rq_addr.sin_port) < 1024;
1257 rqstp->rq_chandle.defer = svc_defer;
1258
1259 if (serv->sv_stats)
1260 serv->sv_stats->netcnt++;
1261 return len;
1262}
1263
1264/*
1265 * Drop request
1266 */
1267void
1268svc_drop(struct svc_rqst *rqstp)
1269{
1270 dprintk("svc: socket %p dropped request\n", rqstp->rq_sock);
1271 svc_sock_release(rqstp);
1272}
1273
1274/*
1275 * Return reply to client.
1276 */
1277int
1278svc_send(struct svc_rqst *rqstp)
1279{
1280 struct svc_sock *svsk;
1281 int len;
1282 struct xdr_buf *xb;
1283
1284 if ((svsk = rqstp->rq_sock) == NULL) {
1285 printk(KERN_WARNING "NULL socket pointer in %s:%d\n",
1286 __FILE__, __LINE__);
1287 return -EFAULT;
1288 }
1289
1290 /* release the receive skb before sending the reply */
1291 svc_release_skb(rqstp);
1292
1293 /* calculate over-all length */
1294 xb = & rqstp->rq_res;
1295 xb->len = xb->head[0].iov_len +
1296 xb->page_len +
1297 xb->tail[0].iov_len;
1298
Ingo Molnar57b47a52006-03-20 22:35:41 -08001299 /* Grab svsk->sk_mutex to serialize outgoing data. */
1300 mutex_lock(&svsk->sk_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301 if (test_bit(SK_DEAD, &svsk->sk_flags))
1302 len = -ENOTCONN;
1303 else
1304 len = svsk->sk_sendto(rqstp);
Ingo Molnar57b47a52006-03-20 22:35:41 -08001305 mutex_unlock(&svsk->sk_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001306 svc_sock_release(rqstp);
1307
1308 if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
1309 return 0;
1310 return len;
1311}
1312
1313/*
1314 * Initialize socket for RPC use and create svc_sock struct
1315 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1316 */
1317static struct svc_sock *
1318svc_setup_socket(struct svc_serv *serv, struct socket *sock,
1319 int *errp, int pmap_register)
1320{
1321 struct svc_sock *svsk;
1322 struct sock *inet;
1323
1324 dprintk("svc: svc_setup_socket %p\n", sock);
1325 if (!(svsk = kmalloc(sizeof(*svsk), GFP_KERNEL))) {
1326 *errp = -ENOMEM;
1327 return NULL;
1328 }
1329 memset(svsk, 0, sizeof(*svsk));
1330
1331 inet = sock->sk;
1332
1333 /* Register socket with portmapper */
1334 if (*errp >= 0 && pmap_register)
1335 *errp = svc_register(serv, inet->sk_protocol,
1336 ntohs(inet_sk(inet)->sport));
1337
1338 if (*errp < 0) {
1339 kfree(svsk);
1340 return NULL;
1341 }
1342
1343 set_bit(SK_BUSY, &svsk->sk_flags);
1344 inet->sk_user_data = svsk;
1345 svsk->sk_sock = sock;
1346 svsk->sk_sk = inet;
1347 svsk->sk_ostate = inet->sk_state_change;
1348 svsk->sk_odata = inet->sk_data_ready;
1349 svsk->sk_owspace = inet->sk_write_space;
1350 svsk->sk_server = serv;
1351 svsk->sk_lastrecv = get_seconds();
1352 INIT_LIST_HEAD(&svsk->sk_deferred);
1353 INIT_LIST_HEAD(&svsk->sk_ready);
Ingo Molnar57b47a52006-03-20 22:35:41 -08001354 mutex_init(&svsk->sk_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355
1356 /* Initialize the socket */
1357 if (sock->type == SOCK_DGRAM)
1358 svc_udp_init(svsk);
1359 else
1360 svc_tcp_init(svsk);
1361
1362 spin_lock_bh(&serv->sv_lock);
1363 if (!pmap_register) {
1364 set_bit(SK_TEMP, &svsk->sk_flags);
1365 list_add(&svsk->sk_list, &serv->sv_tempsocks);
1366 serv->sv_tmpcnt++;
1367 } else {
1368 clear_bit(SK_TEMP, &svsk->sk_flags);
1369 list_add(&svsk->sk_list, &serv->sv_permsocks);
1370 }
1371 spin_unlock_bh(&serv->sv_lock);
1372
1373 dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1374 svsk, svsk->sk_sk);
1375
1376 clear_bit(SK_BUSY, &svsk->sk_flags);
1377 svc_sock_enqueue(svsk);
1378 return svsk;
1379}
1380
1381/*
1382 * Create socket for RPC service.
1383 */
1384static int
1385svc_create_socket(struct svc_serv *serv, int protocol, struct sockaddr_in *sin)
1386{
1387 struct svc_sock *svsk;
1388 struct socket *sock;
1389 int error;
1390 int type;
1391
1392 dprintk("svc: svc_create_socket(%s, %d, %u.%u.%u.%u:%d)\n",
1393 serv->sv_program->pg_name, protocol,
1394 NIPQUAD(sin->sin_addr.s_addr),
1395 ntohs(sin->sin_port));
1396
1397 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1398 printk(KERN_WARNING "svc: only UDP and TCP "
1399 "sockets supported\n");
1400 return -EINVAL;
1401 }
1402 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1403
1404 if ((error = sock_create_kern(PF_INET, type, protocol, &sock)) < 0)
1405 return error;
1406
1407 if (sin != NULL) {
1408 if (type == SOCK_STREAM)
1409 sock->sk->sk_reuse = 1; /* allow address reuse */
1410 error = sock->ops->bind(sock, (struct sockaddr *) sin,
1411 sizeof(*sin));
1412 if (error < 0)
1413 goto bummer;
1414 }
1415
1416 if (protocol == IPPROTO_TCP) {
1417 if ((error = sock->ops->listen(sock, 64)) < 0)
1418 goto bummer;
1419 }
1420
1421 if ((svsk = svc_setup_socket(serv, sock, &error, 1)) != NULL)
1422 return 0;
1423
1424bummer:
1425 dprintk("svc: svc_create_socket error = %d\n", -error);
1426 sock_release(sock);
1427 return error;
1428}
1429
1430/*
1431 * Remove a dead socket
1432 */
1433void
1434svc_delete_socket(struct svc_sock *svsk)
1435{
1436 struct svc_serv *serv;
1437 struct sock *sk;
1438
1439 dprintk("svc: svc_delete_socket(%p)\n", svsk);
1440
1441 serv = svsk->sk_server;
1442 sk = svsk->sk_sk;
1443
1444 sk->sk_state_change = svsk->sk_ostate;
1445 sk->sk_data_ready = svsk->sk_odata;
1446 sk->sk_write_space = svsk->sk_owspace;
1447
1448 spin_lock_bh(&serv->sv_lock);
1449
1450 list_del_init(&svsk->sk_list);
1451 list_del_init(&svsk->sk_ready);
1452 if (!test_and_set_bit(SK_DEAD, &svsk->sk_flags))
1453 if (test_bit(SK_TEMP, &svsk->sk_flags))
1454 serv->sv_tmpcnt--;
1455
1456 if (!svsk->sk_inuse) {
1457 spin_unlock_bh(&serv->sv_lock);
1458 sock_release(svsk->sk_sock);
1459 kfree(svsk);
1460 } else {
1461 spin_unlock_bh(&serv->sv_lock);
1462 dprintk(KERN_NOTICE "svc: server socket destroy delayed\n");
1463 /* svsk->sk_server = NULL; */
1464 }
1465}
1466
1467/*
1468 * Make a socket for nfsd and lockd
1469 */
1470int
1471svc_makesock(struct svc_serv *serv, int protocol, unsigned short port)
1472{
1473 struct sockaddr_in sin;
1474
1475 dprintk("svc: creating socket proto = %d\n", protocol);
1476 sin.sin_family = AF_INET;
1477 sin.sin_addr.s_addr = INADDR_ANY;
1478 sin.sin_port = htons(port);
1479 return svc_create_socket(serv, protocol, &sin);
1480}
1481
1482/*
1483 * Handle defer and revisit of requests
1484 */
1485
1486static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
1487{
1488 struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle);
1489 struct svc_serv *serv = dreq->owner;
1490 struct svc_sock *svsk;
1491
1492 if (too_many) {
1493 svc_sock_put(dr->svsk);
1494 kfree(dr);
1495 return;
1496 }
1497 dprintk("revisit queued\n");
1498 svsk = dr->svsk;
1499 dr->svsk = NULL;
1500 spin_lock_bh(&serv->sv_lock);
1501 list_add(&dr->handle.recent, &svsk->sk_deferred);
1502 spin_unlock_bh(&serv->sv_lock);
1503 set_bit(SK_DEFERRED, &svsk->sk_flags);
1504 svc_sock_enqueue(svsk);
1505 svc_sock_put(svsk);
1506}
1507
1508static struct cache_deferred_req *
1509svc_defer(struct cache_req *req)
1510{
1511 struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
1512 int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
1513 struct svc_deferred_req *dr;
1514
1515 if (rqstp->rq_arg.page_len)
1516 return NULL; /* if more than a page, give up FIXME */
1517 if (rqstp->rq_deferred) {
1518 dr = rqstp->rq_deferred;
1519 rqstp->rq_deferred = NULL;
1520 } else {
1521 int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1522 /* FIXME maybe discard if size too large */
1523 dr = kmalloc(size, GFP_KERNEL);
1524 if (dr == NULL)
1525 return NULL;
1526
1527 dr->handle.owner = rqstp->rq_server;
1528 dr->prot = rqstp->rq_prot;
1529 dr->addr = rqstp->rq_addr;
J. Bruce Fields1918e342006-01-18 17:43:16 -08001530 dr->daddr = rqstp->rq_daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531 dr->argslen = rqstp->rq_arg.len >> 2;
1532 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2);
1533 }
1534 spin_lock_bh(&rqstp->rq_server->sv_lock);
1535 rqstp->rq_sock->sk_inuse++;
1536 dr->svsk = rqstp->rq_sock;
1537 spin_unlock_bh(&rqstp->rq_server->sv_lock);
1538
1539 dr->handle.revisit = svc_revisit;
1540 return &dr->handle;
1541}
1542
1543/*
1544 * recv data from a deferred request into an active one
1545 */
1546static int svc_deferred_recv(struct svc_rqst *rqstp)
1547{
1548 struct svc_deferred_req *dr = rqstp->rq_deferred;
1549
1550 rqstp->rq_arg.head[0].iov_base = dr->args;
1551 rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
1552 rqstp->rq_arg.page_len = 0;
1553 rqstp->rq_arg.len = dr->argslen<<2;
1554 rqstp->rq_prot = dr->prot;
1555 rqstp->rq_addr = dr->addr;
J. Bruce Fields1918e342006-01-18 17:43:16 -08001556 rqstp->rq_daddr = dr->daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557 return dr->argslen<<2;
1558}
1559
1560
1561static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk)
1562{
1563 struct svc_deferred_req *dr = NULL;
1564 struct svc_serv *serv = svsk->sk_server;
1565
1566 if (!test_bit(SK_DEFERRED, &svsk->sk_flags))
1567 return NULL;
1568 spin_lock_bh(&serv->sv_lock);
1569 clear_bit(SK_DEFERRED, &svsk->sk_flags);
1570 if (!list_empty(&svsk->sk_deferred)) {
1571 dr = list_entry(svsk->sk_deferred.next,
1572 struct svc_deferred_req,
1573 handle.recent);
1574 list_del_init(&dr->handle.recent);
1575 set_bit(SK_DEFERRED, &svsk->sk_flags);
1576 }
1577 spin_unlock_bh(&serv->sv_lock);
1578 return dr;
1579}