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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/svcsock.c
4 *
5 * These are the RPC server socket internals.
6 *
7 * The server scheduling algorithm does not always distribute the load
8 * evenly when servicing a single client. May need to modify the
9 * svc_xprt_enqueue procedure...
10 *
11 * TCP support is largely untested and may be a little slow. The problem
12 * is that we currently do two separate recvfrom's, one for the 4-byte
13 * record length, and the second for the actual record. This could possibly
14 * be improved by always reading a minimum size of around 100 bytes and
15 * tucking any superfluous bytes away in a temporary store. Still, that
16 * leaves write requests out in the rain. An alternative may be to peek at
17 * the first skb in the queue, and if it matches the next TCP sequence
18 * number, to extract the record marker. Yuck.
19 *
20 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
21 */
22
23#include <linux/kernel.h>
24#include <linux/sched.h>
25#include <linux/module.h>
26#include <linux/errno.h>
27#include <linux/fcntl.h>
28#include <linux/net.h>
29#include <linux/in.h>
30#include <linux/inet.h>
31#include <linux/udp.h>
32#include <linux/tcp.h>
33#include <linux/unistd.h>
34#include <linux/slab.h>
35#include <linux/netdevice.h>
36#include <linux/skbuff.h>
37#include <linux/file.h>
38#include <linux/freezer.h>
39#include <net/sock.h>
40#include <net/checksum.h>
41#include <net/ip.h>
42#include <net/ipv6.h>
43#include <net/udp.h>
44#include <net/tcp.h>
45#include <net/tcp_states.h>
46#include <linux/uaccess.h>
47#include <linux/highmem.h>
48#include <asm/ioctls.h>
49
50#include <linux/sunrpc/types.h>
51#include <linux/sunrpc/clnt.h>
52#include <linux/sunrpc/xdr.h>
53#include <linux/sunrpc/msg_prot.h>
54#include <linux/sunrpc/svcsock.h>
55#include <linux/sunrpc/stats.h>
56#include <linux/sunrpc/xprt.h>
57
58#include <trace/events/sunrpc.h>
59
60#include "socklib.h"
61#include "sunrpc.h"
62
63#define RPCDBG_FACILITY RPCDBG_SVCXPRT
64
65
66static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
67 int flags);
68static int svc_udp_recvfrom(struct svc_rqst *);
69static int svc_udp_sendto(struct svc_rqst *);
70static void svc_sock_detach(struct svc_xprt *);
71static void svc_tcp_sock_detach(struct svc_xprt *);
72static void svc_sock_free(struct svc_xprt *);
73
74static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
75 struct net *, struct sockaddr *,
76 int, int);
77#ifdef CONFIG_DEBUG_LOCK_ALLOC
78static struct lock_class_key svc_key[2];
79static struct lock_class_key svc_slock_key[2];
80
81static void svc_reclassify_socket(struct socket *sock)
82{
83 struct sock *sk = sock->sk;
84
85 if (WARN_ON_ONCE(!sock_allow_reclassification(sk)))
86 return;
87
88 switch (sk->sk_family) {
89 case AF_INET:
90 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
91 &svc_slock_key[0],
92 "sk_xprt.xpt_lock-AF_INET-NFSD",
93 &svc_key[0]);
94 break;
95
96 case AF_INET6:
97 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
98 &svc_slock_key[1],
99 "sk_xprt.xpt_lock-AF_INET6-NFSD",
100 &svc_key[1]);
101 break;
102
103 default:
104 BUG();
105 }
106}
107#else
108static void svc_reclassify_socket(struct socket *sock)
109{
110}
111#endif
112
113/**
114 * svc_tcp_release_rqst - Release transport-related resources
115 * @rqstp: request structure with resources to be released
116 *
117 */
118static void svc_tcp_release_rqst(struct svc_rqst *rqstp)
119{
120 struct sk_buff *skb = rqstp->rq_xprt_ctxt;
121
122 if (skb) {
123 struct svc_sock *svsk =
124 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
125
126 rqstp->rq_xprt_ctxt = NULL;
127 skb_free_datagram_locked(svsk->sk_sk, skb);
128 }
129}
130
131/**
132 * svc_udp_release_rqst - Release transport-related resources
133 * @rqstp: request structure with resources to be released
134 *
135 */
136static void svc_udp_release_rqst(struct svc_rqst *rqstp)
137{
138 struct sk_buff *skb = rqstp->rq_xprt_ctxt;
139
140 if (skb) {
141 rqstp->rq_xprt_ctxt = NULL;
142 consume_skb(skb);
143 }
144}
145
146union svc_pktinfo_u {
147 struct in_pktinfo pkti;
148 struct in6_pktinfo pkti6;
149};
150#define SVC_PKTINFO_SPACE \
151 CMSG_SPACE(sizeof(union svc_pktinfo_u))
152
153static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
154{
155 struct svc_sock *svsk =
156 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
157 switch (svsk->sk_sk->sk_family) {
158 case AF_INET: {
159 struct in_pktinfo *pki = CMSG_DATA(cmh);
160
161 cmh->cmsg_level = SOL_IP;
162 cmh->cmsg_type = IP_PKTINFO;
163 pki->ipi_ifindex = 0;
164 pki->ipi_spec_dst.s_addr =
165 svc_daddr_in(rqstp)->sin_addr.s_addr;
166 cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
167 }
168 break;
169
170 case AF_INET6: {
171 struct in6_pktinfo *pki = CMSG_DATA(cmh);
172 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
173
174 cmh->cmsg_level = SOL_IPV6;
175 cmh->cmsg_type = IPV6_PKTINFO;
176 pki->ipi6_ifindex = daddr->sin6_scope_id;
177 pki->ipi6_addr = daddr->sin6_addr;
178 cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
179 }
180 break;
181 }
182}
183
184static int svc_sock_read_payload(struct svc_rqst *rqstp, unsigned int offset,
185 unsigned int length)
186{
187 return 0;
188}
189
190/*
191 * Report socket names for nfsdfs
192 */
193static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
194{
195 const struct sock *sk = svsk->sk_sk;
196 const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
197 "udp" : "tcp";
198 int len;
199
200 switch (sk->sk_family) {
201 case PF_INET:
202 len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
203 proto_name,
204 &inet_sk(sk)->inet_rcv_saddr,
205 inet_sk(sk)->inet_num);
206 break;
207#if IS_ENABLED(CONFIG_IPV6)
208 case PF_INET6:
209 len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
210 proto_name,
211 &sk->sk_v6_rcv_saddr,
212 inet_sk(sk)->inet_num);
213 break;
214#endif
215 default:
216 len = snprintf(buf, remaining, "*unknown-%d*\n",
217 sk->sk_family);
218 }
219
220 if (len >= remaining) {
221 *buf = '\0';
222 return -ENAMETOOLONG;
223 }
224 return len;
225}
226
227#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
228static void svc_flush_bvec(const struct bio_vec *bvec, size_t size, size_t seek)
229{
230 struct bvec_iter bi = {
231 .bi_size = size + seek,
232 };
233 struct bio_vec bv;
234
235 bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
236 for_each_bvec(bv, bvec, bi, bi)
237 flush_dcache_page(bv.bv_page);
238}
239#else
240static inline void svc_flush_bvec(const struct bio_vec *bvec, size_t size,
241 size_t seek)
242{
243}
244#endif
245
246/*
247 * Read from @rqstp's transport socket. The incoming message fills whole
248 * pages in @rqstp's rq_pages array until the last page of the message
249 * has been received into a partial page.
250 */
251static ssize_t svc_tcp_read_msg(struct svc_rqst *rqstp, size_t buflen,
252 size_t seek)
253{
254 struct svc_sock *svsk =
255 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
256 struct bio_vec *bvec = rqstp->rq_bvec;
257 struct msghdr msg = { NULL };
258 unsigned int i;
259 ssize_t len;
260 size_t t;
261
262 rqstp->rq_xprt_hlen = 0;
263
264 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
265
266 for (i = 0, t = 0; t < buflen; i++, t += PAGE_SIZE) {
267 bvec[i].bv_page = rqstp->rq_pages[i];
268 bvec[i].bv_len = PAGE_SIZE;
269 bvec[i].bv_offset = 0;
270 }
271 rqstp->rq_respages = &rqstp->rq_pages[i];
272 rqstp->rq_next_page = rqstp->rq_respages + 1;
273
274 iov_iter_bvec(&msg.msg_iter, READ, bvec, i, buflen);
275 if (seek) {
276 iov_iter_advance(&msg.msg_iter, seek);
277 buflen -= seek;
278 }
279 len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT);
280 if (len > 0)
281 svc_flush_bvec(bvec, len, seek);
282
283 /* If we read a full record, then assume there may be more
284 * data to read (stream based sockets only!)
285 */
286 if (len == buflen)
287 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
288
289 return len;
290}
291
292/*
293 * Set socket snd and rcv buffer lengths
294 */
295static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs)
296{
297 unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg;
298 struct socket *sock = svsk->sk_sock;
299
300 nreqs = min(nreqs, INT_MAX / 2 / max_mesg);
301
302 lock_sock(sock->sk);
303 sock->sk->sk_sndbuf = nreqs * max_mesg * 2;
304 sock->sk->sk_rcvbuf = nreqs * max_mesg * 2;
305 sock->sk->sk_write_space(sock->sk);
306 release_sock(sock->sk);
307}
308
309static void svc_sock_secure_port(struct svc_rqst *rqstp)
310{
311 if (svc_port_is_privileged(svc_addr(rqstp)))
312 set_bit(RQ_SECURE, &rqstp->rq_flags);
313 else
314 clear_bit(RQ_SECURE, &rqstp->rq_flags);
315}
316
317/*
318 * INET callback when data has been received on the socket.
319 */
320static void svc_data_ready(struct sock *sk)
321{
322 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
323
324 if (svsk) {
325 /* Refer to svc_setup_socket() for details. */
326 rmb();
327 svsk->sk_odata(sk);
328 trace_svcsock_data_ready(&svsk->sk_xprt, 0);
329 if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags))
330 svc_xprt_enqueue(&svsk->sk_xprt);
331 }
332}
333
334/*
335 * INET callback when space is newly available on the socket.
336 */
337static void svc_write_space(struct sock *sk)
338{
339 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
340
341 if (svsk) {
342 /* Refer to svc_setup_socket() for details. */
343 rmb();
344 trace_svcsock_write_space(&svsk->sk_xprt, 0);
345 svsk->sk_owspace(sk);
346 svc_xprt_enqueue(&svsk->sk_xprt);
347 }
348}
349
350static int svc_tcp_has_wspace(struct svc_xprt *xprt)
351{
352 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
353
354 if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
355 return 1;
356 return !test_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
357}
358
359static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt)
360{
361 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
362
363 sock_no_linger(svsk->sk_sock->sk);
364}
365
366/*
367 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
368 */
369static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
370 struct cmsghdr *cmh)
371{
372 struct in_pktinfo *pki = CMSG_DATA(cmh);
373 struct sockaddr_in *daddr = svc_daddr_in(rqstp);
374
375 if (cmh->cmsg_type != IP_PKTINFO)
376 return 0;
377
378 daddr->sin_family = AF_INET;
379 daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
380 return 1;
381}
382
383/*
384 * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
385 */
386static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
387 struct cmsghdr *cmh)
388{
389 struct in6_pktinfo *pki = CMSG_DATA(cmh);
390 struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
391
392 if (cmh->cmsg_type != IPV6_PKTINFO)
393 return 0;
394
395 daddr->sin6_family = AF_INET6;
396 daddr->sin6_addr = pki->ipi6_addr;
397 daddr->sin6_scope_id = pki->ipi6_ifindex;
398 return 1;
399}
400
401/*
402 * Copy the UDP datagram's destination address to the rqstp structure.
403 * The 'destination' address in this case is the address to which the
404 * peer sent the datagram, i.e. our local address. For multihomed
405 * hosts, this can change from msg to msg. Note that only the IP
406 * address changes, the port number should remain the same.
407 */
408static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
409 struct cmsghdr *cmh)
410{
411 switch (cmh->cmsg_level) {
412 case SOL_IP:
413 return svc_udp_get_dest_address4(rqstp, cmh);
414 case SOL_IPV6:
415 return svc_udp_get_dest_address6(rqstp, cmh);
416 }
417
418 return 0;
419}
420
421/**
422 * svc_udp_recvfrom - Receive a datagram from a UDP socket.
423 * @rqstp: request structure into which to receive an RPC Call
424 *
425 * Called in a loop when XPT_DATA has been set.
426 *
427 * Returns:
428 * On success, the number of bytes in a received RPC Call, or
429 * %0 if a complete RPC Call message was not ready to return
430 */
431static int svc_udp_recvfrom(struct svc_rqst *rqstp)
432{
433 struct svc_sock *svsk =
434 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
435 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
436 struct sk_buff *skb;
437 union {
438 struct cmsghdr hdr;
439 long all[SVC_PKTINFO_SPACE / sizeof(long)];
440 } buffer;
441 struct cmsghdr *cmh = &buffer.hdr;
442 struct msghdr msg = {
443 .msg_name = svc_addr(rqstp),
444 .msg_control = cmh,
445 .msg_controllen = sizeof(buffer),
446 .msg_flags = MSG_DONTWAIT,
447 };
448 size_t len;
449 int err;
450
451 if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
452 /* udp sockets need large rcvbuf as all pending
453 * requests are still in that buffer. sndbuf must
454 * also be large enough that there is enough space
455 * for one reply per thread. We count all threads
456 * rather than threads in a particular pool, which
457 * provides an upper bound on the number of threads
458 * which will access the socket.
459 */
460 svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3);
461
462 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
463 err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
464 0, 0, MSG_PEEK | MSG_DONTWAIT);
465 if (err < 0)
466 goto out_recv_err;
467 skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err);
468 if (!skb)
469 goto out_recv_err;
470
471 len = svc_addr_len(svc_addr(rqstp));
472 rqstp->rq_addrlen = len;
473 if (skb->tstamp == 0) {
474 skb->tstamp = ktime_get_real();
475 /* Don't enable netstamp, sunrpc doesn't
476 need that much accuracy */
477 }
478 sock_write_timestamp(svsk->sk_sk, skb->tstamp);
479 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
480
481 len = skb->len;
482 rqstp->rq_arg.len = len;
483 trace_svcsock_udp_recv(&svsk->sk_xprt, len);
484
485 rqstp->rq_prot = IPPROTO_UDP;
486
487 if (!svc_udp_get_dest_address(rqstp, cmh))
488 goto out_cmsg_err;
489 rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
490
491 if (skb_is_nonlinear(skb)) {
492 /* we have to copy */
493 local_bh_disable();
494 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb))
495 goto out_bh_enable;
496 local_bh_enable();
497 consume_skb(skb);
498 } else {
499 /* we can use it in-place */
500 rqstp->rq_arg.head[0].iov_base = skb->data;
501 rqstp->rq_arg.head[0].iov_len = len;
502 if (skb_checksum_complete(skb))
503 goto out_free;
504 rqstp->rq_xprt_ctxt = skb;
505 }
506
507 rqstp->rq_arg.page_base = 0;
508 if (len <= rqstp->rq_arg.head[0].iov_len) {
509 rqstp->rq_arg.head[0].iov_len = len;
510 rqstp->rq_arg.page_len = 0;
511 rqstp->rq_respages = rqstp->rq_pages+1;
512 } else {
513 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
514 rqstp->rq_respages = rqstp->rq_pages + 1 +
515 DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
516 }
517 rqstp->rq_next_page = rqstp->rq_respages+1;
518
519 if (serv->sv_stats)
520 serv->sv_stats->netudpcnt++;
521
522 return len;
523
524out_recv_err:
525 if (err != -EAGAIN) {
526 /* possibly an icmp error */
527 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
528 }
529 trace_svcsock_udp_recv_err(&svsk->sk_xprt, err);
530 return 0;
531out_cmsg_err:
532 net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
533 cmh->cmsg_level, cmh->cmsg_type);
534 goto out_free;
535out_bh_enable:
536 local_bh_enable();
537out_free:
538 kfree_skb(skb);
539 return 0;
540}
541
542/**
543 * svc_udp_sendto - Send out a reply on a UDP socket
544 * @rqstp: completed svc_rqst
545 *
546 * xpt_mutex ensures @rqstp's whole message is written to the socket
547 * without interruption.
548 *
549 * Returns the number of bytes sent, or a negative errno.
550 */
551static int svc_udp_sendto(struct svc_rqst *rqstp)
552{
553 struct svc_xprt *xprt = rqstp->rq_xprt;
554 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
555 struct xdr_buf *xdr = &rqstp->rq_res;
556 union {
557 struct cmsghdr hdr;
558 long all[SVC_PKTINFO_SPACE / sizeof(long)];
559 } buffer;
560 struct cmsghdr *cmh = &buffer.hdr;
561 struct msghdr msg = {
562 .msg_name = &rqstp->rq_addr,
563 .msg_namelen = rqstp->rq_addrlen,
564 .msg_control = cmh,
565 .msg_controllen = sizeof(buffer),
566 };
567 unsigned int sent;
568 int err;
569
570 svc_udp_release_rqst(rqstp);
571
572 svc_set_cmsg_data(rqstp, cmh);
573
574 mutex_lock(&xprt->xpt_mutex);
575
576 if (svc_xprt_is_dead(xprt))
577 goto out_notconn;
578
579 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent);
580 xdr_free_bvec(xdr);
581 if (err == -ECONNREFUSED) {
582 /* ICMP error on earlier request. */
583 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, 0, &sent);
584 xdr_free_bvec(xdr);
585 }
586 trace_svcsock_udp_send(xprt, err);
587
588 mutex_unlock(&xprt->xpt_mutex);
589 if (err < 0)
590 return err;
591 return sent;
592
593out_notconn:
594 mutex_unlock(&xprt->xpt_mutex);
595 return -ENOTCONN;
596}
597
598static int svc_udp_has_wspace(struct svc_xprt *xprt)
599{
600 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
601 struct svc_serv *serv = xprt->xpt_server;
602 unsigned long required;
603
604 /*
605 * Set the SOCK_NOSPACE flag before checking the available
606 * sock space.
607 */
608 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
609 required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
610 if (required*2 > sock_wspace(svsk->sk_sk))
611 return 0;
612 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
613 return 1;
614}
615
616static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
617{
618 BUG();
619 return NULL;
620}
621
622static void svc_udp_kill_temp_xprt(struct svc_xprt *xprt)
623{
624}
625
626static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
627 struct net *net,
628 struct sockaddr *sa, int salen,
629 int flags)
630{
631 return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
632}
633
634static const struct svc_xprt_ops svc_udp_ops = {
635 .xpo_create = svc_udp_create,
636 .xpo_recvfrom = svc_udp_recvfrom,
637 .xpo_sendto = svc_udp_sendto,
638 .xpo_read_payload = svc_sock_read_payload,
639 .xpo_release_rqst = svc_udp_release_rqst,
640 .xpo_detach = svc_sock_detach,
641 .xpo_free = svc_sock_free,
642 .xpo_has_wspace = svc_udp_has_wspace,
643 .xpo_accept = svc_udp_accept,
644 .xpo_secure_port = svc_sock_secure_port,
645 .xpo_kill_temp_xprt = svc_udp_kill_temp_xprt,
646};
647
648static struct svc_xprt_class svc_udp_class = {
649 .xcl_name = "udp",
650 .xcl_owner = THIS_MODULE,
651 .xcl_ops = &svc_udp_ops,
652 .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
653 .xcl_ident = XPRT_TRANSPORT_UDP,
654};
655
656static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
657{
658 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
659 &svsk->sk_xprt, serv);
660 clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
661 svsk->sk_sk->sk_data_ready = svc_data_ready;
662 svsk->sk_sk->sk_write_space = svc_write_space;
663
664 /* initialise setting must have enough space to
665 * receive and respond to one request.
666 * svc_udp_recvfrom will re-adjust if necessary
667 */
668 svc_sock_setbufsize(svsk, 3);
669
670 /* data might have come in before data_ready set up */
671 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
672 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
673
674 /* make sure we get destination address info */
675 switch (svsk->sk_sk->sk_family) {
676 case AF_INET:
677 ip_sock_set_pktinfo(svsk->sk_sock->sk);
678 break;
679 case AF_INET6:
680 ip6_sock_set_recvpktinfo(svsk->sk_sock->sk);
681 break;
682 default:
683 BUG();
684 }
685}
686
687/*
688 * A data_ready event on a listening socket means there's a connection
689 * pending. Do not use state_change as a substitute for it.
690 */
691static void svc_tcp_listen_data_ready(struct sock *sk)
692{
693 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
694
695 if (svsk) {
696 /* Refer to svc_setup_socket() for details. */
697 rmb();
698 svsk->sk_odata(sk);
699 }
700
701 /*
702 * This callback may called twice when a new connection
703 * is established as a child socket inherits everything
704 * from a parent LISTEN socket.
705 * 1) data_ready method of the parent socket will be called
706 * when one of child sockets become ESTABLISHED.
707 * 2) data_ready method of the child socket may be called
708 * when it receives data before the socket is accepted.
709 * In case of 2, we should ignore it silently.
710 */
711 if (sk->sk_state == TCP_LISTEN) {
712 if (svsk) {
713 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
714 svc_xprt_enqueue(&svsk->sk_xprt);
715 }
716 }
717}
718
719/*
720 * A state change on a connected socket means it's dying or dead.
721 */
722static void svc_tcp_state_change(struct sock *sk)
723{
724 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
725
726 if (svsk) {
727 /* Refer to svc_setup_socket() for details. */
728 rmb();
729 svsk->sk_ostate(sk);
730 trace_svcsock_tcp_state(&svsk->sk_xprt, svsk->sk_sock);
731 if (sk->sk_state != TCP_ESTABLISHED) {
732 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
733 svc_xprt_enqueue(&svsk->sk_xprt);
734 }
735 }
736}
737
738/*
739 * Accept a TCP connection
740 */
741static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
742{
743 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
744 struct sockaddr_storage addr;
745 struct sockaddr *sin = (struct sockaddr *) &addr;
746 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
747 struct socket *sock = svsk->sk_sock;
748 struct socket *newsock;
749 struct svc_sock *newsvsk;
750 int err, slen;
751
752 if (!sock)
753 return NULL;
754
755 clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
756 err = kernel_accept(sock, &newsock, O_NONBLOCK);
757 if (err < 0) {
758 if (err == -ENOMEM)
759 printk(KERN_WARNING "%s: no more sockets!\n",
760 serv->sv_name);
761 else if (err != -EAGAIN)
762 net_warn_ratelimited("%s: accept failed (err %d)!\n",
763 serv->sv_name, -err);
764 trace_svcsock_accept_err(xprt, serv->sv_name, err);
765 return NULL;
766 }
767 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
768
769 err = kernel_getpeername(newsock, sin);
770 if (err < 0) {
771 trace_svcsock_getpeername_err(xprt, serv->sv_name, err);
772 goto failed; /* aborted connection or whatever */
773 }
774 slen = err;
775
776 /* Reset the inherited callbacks before calling svc_setup_socket */
777 newsock->sk->sk_state_change = svsk->sk_ostate;
778 newsock->sk->sk_data_ready = svsk->sk_odata;
779 newsock->sk->sk_write_space = svsk->sk_owspace;
780
781 /* make sure that a write doesn't block forever when
782 * low on memory
783 */
784 newsock->sk->sk_sndtimeo = HZ*30;
785
786 newsvsk = svc_setup_socket(serv, newsock,
787 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY));
788 if (IS_ERR(newsvsk))
789 goto failed;
790 svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
791 err = kernel_getsockname(newsock, sin);
792 slen = err;
793 if (unlikely(err < 0))
794 slen = offsetof(struct sockaddr, sa_data);
795 svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
796
797 if (sock_is_loopback(newsock->sk))
798 set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
799 else
800 clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
801 if (serv->sv_stats)
802 serv->sv_stats->nettcpconn++;
803
804 return &newsvsk->sk_xprt;
805
806failed:
807 sock_release(newsock);
808 return NULL;
809}
810
811static size_t svc_tcp_restore_pages(struct svc_sock *svsk,
812 struct svc_rqst *rqstp)
813{
814 size_t len = svsk->sk_datalen;
815 unsigned int i, npages;
816
817 if (!len)
818 return 0;
819 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
820 for (i = 0; i < npages; i++) {
821 if (rqstp->rq_pages[i] != NULL)
822 put_page(rqstp->rq_pages[i]);
823 BUG_ON(svsk->sk_pages[i] == NULL);
824 rqstp->rq_pages[i] = svsk->sk_pages[i];
825 svsk->sk_pages[i] = NULL;
826 }
827 rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
828 return len;
829}
830
831static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
832{
833 unsigned int i, len, npages;
834
835 if (svsk->sk_datalen == 0)
836 return;
837 len = svsk->sk_datalen;
838 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
839 for (i = 0; i < npages; i++) {
840 svsk->sk_pages[i] = rqstp->rq_pages[i];
841 rqstp->rq_pages[i] = NULL;
842 }
843}
844
845static void svc_tcp_clear_pages(struct svc_sock *svsk)
846{
847 unsigned int i, len, npages;
848
849 if (svsk->sk_datalen == 0)
850 goto out;
851 len = svsk->sk_datalen;
852 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
853 for (i = 0; i < npages; i++) {
854 if (svsk->sk_pages[i] == NULL) {
855 WARN_ON_ONCE(1);
856 continue;
857 }
858 put_page(svsk->sk_pages[i]);
859 svsk->sk_pages[i] = NULL;
860 }
861out:
862 svsk->sk_tcplen = 0;
863 svsk->sk_datalen = 0;
864}
865
866/*
867 * Receive fragment record header into sk_marker.
868 */
869static ssize_t svc_tcp_read_marker(struct svc_sock *svsk,
870 struct svc_rqst *rqstp)
871{
872 ssize_t want, len;
873
874 /* If we haven't gotten the record length yet,
875 * get the next four bytes.
876 */
877 if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
878 struct msghdr msg = { NULL };
879 struct kvec iov;
880
881 want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
882 iov.iov_base = ((char *)&svsk->sk_marker) + svsk->sk_tcplen;
883 iov.iov_len = want;
884 iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, want);
885 len = sock_recvmsg(svsk->sk_sock, &msg, MSG_DONTWAIT);
886 if (len < 0)
887 return len;
888 svsk->sk_tcplen += len;
889 if (len < want) {
890 /* call again to read the remaining bytes */
891 goto err_short;
892 }
893 trace_svcsock_marker(&svsk->sk_xprt, svsk->sk_marker);
894 if (svc_sock_reclen(svsk) + svsk->sk_datalen >
895 svsk->sk_xprt.xpt_server->sv_max_mesg)
896 goto err_too_large;
897 }
898 return svc_sock_reclen(svsk);
899
900err_too_large:
901 net_notice_ratelimited("svc: %s %s RPC fragment too large: %d\n",
902 __func__, svsk->sk_xprt.xpt_server->sv_name,
903 svc_sock_reclen(svsk));
904 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
905err_short:
906 return -EAGAIN;
907}
908
909static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
910{
911 struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
912 struct rpc_rqst *req = NULL;
913 struct kvec *src, *dst;
914 __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
915 __be32 xid;
916 __be32 calldir;
917
918 xid = *p++;
919 calldir = *p;
920
921 if (!bc_xprt)
922 return -EAGAIN;
923 spin_lock(&bc_xprt->queue_lock);
924 req = xprt_lookup_rqst(bc_xprt, xid);
925 if (!req)
926 goto unlock_notfound;
927
928 memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
929 /*
930 * XXX!: cheating for now! Only copying HEAD.
931 * But we know this is good enough for now (in fact, for any
932 * callback reply in the forseeable future).
933 */
934 dst = &req->rq_private_buf.head[0];
935 src = &rqstp->rq_arg.head[0];
936 if (dst->iov_len < src->iov_len)
937 goto unlock_eagain; /* whatever; just giving up. */
938 memcpy(dst->iov_base, src->iov_base, src->iov_len);
939 xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
940 rqstp->rq_arg.len = 0;
941 spin_unlock(&bc_xprt->queue_lock);
942 return 0;
943unlock_notfound:
944 printk(KERN_NOTICE
945 "%s: Got unrecognized reply: "
946 "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
947 __func__, ntohl(calldir),
948 bc_xprt, ntohl(xid));
949unlock_eagain:
950 spin_unlock(&bc_xprt->queue_lock);
951 return -EAGAIN;
952}
953
954static void svc_tcp_fragment_received(struct svc_sock *svsk)
955{
956 /* If we have more data, signal svc_xprt_enqueue() to try again */
957 svsk->sk_tcplen = 0;
958 svsk->sk_marker = xdr_zero;
959}
960
961/**
962 * svc_tcp_recvfrom - Receive data from a TCP socket
963 * @rqstp: request structure into which to receive an RPC Call
964 *
965 * Called in a loop when XPT_DATA has been set.
966 *
967 * Read the 4-byte stream record marker, then use the record length
968 * in that marker to set up exactly the resources needed to receive
969 * the next RPC message into @rqstp.
970 *
971 * Returns:
972 * On success, the number of bytes in a received RPC Call, or
973 * %0 if a complete RPC Call message was not ready to return
974 *
975 * The zero return case handles partial receives and callback Replies.
976 * The state of a partial receive is preserved in the svc_sock for
977 * the next call to svc_tcp_recvfrom.
978 */
979static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
980{
981 struct svc_sock *svsk =
982 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
983 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
984 size_t want, base;
985 ssize_t len;
986 __be32 *p;
987 __be32 calldir;
988
989 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
990 len = svc_tcp_read_marker(svsk, rqstp);
991 if (len < 0)
992 goto error;
993
994 base = svc_tcp_restore_pages(svsk, rqstp);
995 want = len - (svsk->sk_tcplen - sizeof(rpc_fraghdr));
996 len = svc_tcp_read_msg(rqstp, base + want, base);
997 if (len >= 0) {
998 trace_svcsock_tcp_recv(&svsk->sk_xprt, len);
999 svsk->sk_tcplen += len;
1000 svsk->sk_datalen += len;
1001 }
1002 if (len != want || !svc_sock_final_rec(svsk))
1003 goto err_incomplete;
1004 if (svsk->sk_datalen < 8)
1005 goto err_nuts;
1006
1007 rqstp->rq_arg.len = svsk->sk_datalen;
1008 rqstp->rq_arg.page_base = 0;
1009 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1010 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1011 rqstp->rq_arg.page_len = 0;
1012 } else
1013 rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1014
1015 rqstp->rq_xprt_ctxt = NULL;
1016 rqstp->rq_prot = IPPROTO_TCP;
1017 if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags))
1018 set_bit(RQ_LOCAL, &rqstp->rq_flags);
1019 else
1020 clear_bit(RQ_LOCAL, &rqstp->rq_flags);
1021
1022 p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1023 calldir = p[1];
1024 if (calldir)
1025 len = receive_cb_reply(svsk, rqstp);
1026
1027 /* Reset TCP read info */
1028 svsk->sk_datalen = 0;
1029 svc_tcp_fragment_received(svsk);
1030
1031 if (len < 0)
1032 goto error;
1033
1034 svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1035 if (serv->sv_stats)
1036 serv->sv_stats->nettcpcnt++;
1037
1038 return rqstp->rq_arg.len;
1039
1040err_incomplete:
1041 svc_tcp_save_pages(svsk, rqstp);
1042 if (len < 0 && len != -EAGAIN)
1043 goto err_delete;
1044 if (len == want)
1045 svc_tcp_fragment_received(svsk);
1046 else
1047 trace_svcsock_tcp_recv_short(&svsk->sk_xprt,
1048 svc_sock_reclen(svsk),
1049 svsk->sk_tcplen - sizeof(rpc_fraghdr));
1050 goto err_noclose;
1051error:
1052 if (len != -EAGAIN)
1053 goto err_delete;
1054 trace_svcsock_tcp_recv_eagain(&svsk->sk_xprt, 0);
1055 return 0;
1056err_nuts:
1057 svsk->sk_datalen = 0;
1058err_delete:
1059 trace_svcsock_tcp_recv_err(&svsk->sk_xprt, len);
1060 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1061err_noclose:
1062 return 0; /* record not complete */
1063}
1064
1065/**
1066 * svc_tcp_sendto - Send out a reply on a TCP socket
1067 * @rqstp: completed svc_rqst
1068 *
1069 * xpt_mutex ensures @rqstp's whole message is written to the socket
1070 * without interruption.
1071 *
1072 * Returns the number of bytes sent, or a negative errno.
1073 */
1074static int svc_tcp_sendto(struct svc_rqst *rqstp)
1075{
1076 struct svc_xprt *xprt = rqstp->rq_xprt;
1077 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1078 struct xdr_buf *xdr = &rqstp->rq_res;
1079 rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
1080 (u32)xdr->len);
1081 struct msghdr msg = {
1082 .msg_flags = 0,
1083 };
1084 unsigned int sent;
1085 int err;
1086
1087 svc_tcp_release_rqst(rqstp);
1088
1089 mutex_lock(&xprt->xpt_mutex);
1090 if (svc_xprt_is_dead(xprt))
1091 goto out_notconn;
1092 err = xprt_sock_sendmsg(svsk->sk_sock, &msg, xdr, 0, marker, &sent);
1093 xdr_free_bvec(xdr);
1094 trace_svcsock_tcp_send(xprt, err < 0 ? err : sent);
1095 if (err < 0 || sent != (xdr->len + sizeof(marker)))
1096 goto out_close;
1097 mutex_unlock(&xprt->xpt_mutex);
1098 return sent;
1099
1100out_notconn:
1101 mutex_unlock(&xprt->xpt_mutex);
1102 return -ENOTCONN;
1103out_close:
1104 pr_notice("rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n",
1105 xprt->xpt_server->sv_name,
1106 (err < 0) ? "got error" : "sent",
1107 (err < 0) ? err : sent, xdr->len);
1108 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1109 svc_xprt_enqueue(xprt);
1110 mutex_unlock(&xprt->xpt_mutex);
1111 return -EAGAIN;
1112}
1113
1114static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1115 struct net *net,
1116 struct sockaddr *sa, int salen,
1117 int flags)
1118{
1119 return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1120}
1121
1122static const struct svc_xprt_ops svc_tcp_ops = {
1123 .xpo_create = svc_tcp_create,
1124 .xpo_recvfrom = svc_tcp_recvfrom,
1125 .xpo_sendto = svc_tcp_sendto,
1126 .xpo_read_payload = svc_sock_read_payload,
1127 .xpo_release_rqst = svc_tcp_release_rqst,
1128 .xpo_detach = svc_tcp_sock_detach,
1129 .xpo_free = svc_sock_free,
1130 .xpo_has_wspace = svc_tcp_has_wspace,
1131 .xpo_accept = svc_tcp_accept,
1132 .xpo_secure_port = svc_sock_secure_port,
1133 .xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt,
1134};
1135
1136static struct svc_xprt_class svc_tcp_class = {
1137 .xcl_name = "tcp",
1138 .xcl_owner = THIS_MODULE,
1139 .xcl_ops = &svc_tcp_ops,
1140 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1141 .xcl_ident = XPRT_TRANSPORT_TCP,
1142};
1143
1144void svc_init_xprt_sock(void)
1145{
1146 svc_reg_xprt_class(&svc_tcp_class);
1147 svc_reg_xprt_class(&svc_udp_class);
1148}
1149
1150void svc_cleanup_xprt_sock(void)
1151{
1152 svc_unreg_xprt_class(&svc_tcp_class);
1153 svc_unreg_xprt_class(&svc_udp_class);
1154}
1155
1156static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1157{
1158 struct sock *sk = svsk->sk_sk;
1159
1160 svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
1161 &svsk->sk_xprt, serv);
1162 set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1163 set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags);
1164 if (sk->sk_state == TCP_LISTEN) {
1165 strcpy(svsk->sk_xprt.xpt_remotebuf, "listener");
1166 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1167 sk->sk_data_ready = svc_tcp_listen_data_ready;
1168 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1169 } else {
1170 sk->sk_state_change = svc_tcp_state_change;
1171 sk->sk_data_ready = svc_data_ready;
1172 sk->sk_write_space = svc_write_space;
1173
1174 svsk->sk_marker = xdr_zero;
1175 svsk->sk_tcplen = 0;
1176 svsk->sk_datalen = 0;
1177 memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1178
1179 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1180
1181 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1182 switch (sk->sk_state) {
1183 case TCP_SYN_RECV:
1184 case TCP_ESTABLISHED:
1185 break;
1186 default:
1187 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1188 }
1189 }
1190}
1191
1192void svc_sock_update_bufs(struct svc_serv *serv)
1193{
1194 /*
1195 * The number of server threads has changed. Update
1196 * rcvbuf and sndbuf accordingly on all sockets
1197 */
1198 struct svc_sock *svsk;
1199
1200 spin_lock_bh(&serv->sv_lock);
1201 list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1202 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1203 spin_unlock_bh(&serv->sv_lock);
1204}
1205EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1206
1207/*
1208 * Initialize socket for RPC use and create svc_sock struct
1209 */
1210static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1211 struct socket *sock,
1212 int flags)
1213{
1214 struct svc_sock *svsk;
1215 struct sock *inet;
1216 int pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1217 int err = 0;
1218
1219 svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1220 if (!svsk)
1221 return ERR_PTR(-ENOMEM);
1222
1223 inet = sock->sk;
1224
1225 /* Register socket with portmapper */
1226 if (pmap_register)
1227 err = svc_register(serv, sock_net(sock->sk), inet->sk_family,
1228 inet->sk_protocol,
1229 ntohs(inet_sk(inet)->inet_sport));
1230
1231 if (err < 0) {
1232 kfree(svsk);
1233 return ERR_PTR(err);
1234 }
1235
1236 svsk->sk_sock = sock;
1237 svsk->sk_sk = inet;
1238 svsk->sk_ostate = inet->sk_state_change;
1239 svsk->sk_odata = inet->sk_data_ready;
1240 svsk->sk_owspace = inet->sk_write_space;
1241 /*
1242 * This barrier is necessary in order to prevent race condition
1243 * with svc_data_ready(), svc_listen_data_ready() and others
1244 * when calling callbacks above.
1245 */
1246 wmb();
1247 inet->sk_user_data = svsk;
1248
1249 /* Initialize the socket */
1250 if (sock->type == SOCK_DGRAM)
1251 svc_udp_init(svsk, serv);
1252 else
1253 svc_tcp_init(svsk, serv);
1254
1255 trace_svcsock_new_socket(sock);
1256 return svsk;
1257}
1258
1259bool svc_alien_sock(struct net *net, int fd)
1260{
1261 int err;
1262 struct socket *sock = sockfd_lookup(fd, &err);
1263 bool ret = false;
1264
1265 if (!sock)
1266 goto out;
1267 if (sock_net(sock->sk) != net)
1268 ret = true;
1269 sockfd_put(sock);
1270out:
1271 return ret;
1272}
1273EXPORT_SYMBOL_GPL(svc_alien_sock);
1274
1275/**
1276 * svc_addsock - add a listener socket to an RPC service
1277 * @serv: pointer to RPC service to which to add a new listener
1278 * @fd: file descriptor of the new listener
1279 * @name_return: pointer to buffer to fill in with name of listener
1280 * @len: size of the buffer
1281 * @cred: credential
1282 *
1283 * Fills in socket name and returns positive length of name if successful.
1284 * Name is terminated with '\n'. On error, returns a negative errno
1285 * value.
1286 */
1287int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1288 const size_t len, const struct cred *cred)
1289{
1290 int err = 0;
1291 struct socket *so = sockfd_lookup(fd, &err);
1292 struct svc_sock *svsk = NULL;
1293 struct sockaddr_storage addr;
1294 struct sockaddr *sin = (struct sockaddr *)&addr;
1295 int salen;
1296
1297 if (!so)
1298 return err;
1299 err = -EAFNOSUPPORT;
1300 if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1301 goto out;
1302 err = -EPROTONOSUPPORT;
1303 if (so->sk->sk_protocol != IPPROTO_TCP &&
1304 so->sk->sk_protocol != IPPROTO_UDP)
1305 goto out;
1306 err = -EISCONN;
1307 if (so->state > SS_UNCONNECTED)
1308 goto out;
1309 err = -ENOENT;
1310 if (!try_module_get(THIS_MODULE))
1311 goto out;
1312 svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS);
1313 if (IS_ERR(svsk)) {
1314 module_put(THIS_MODULE);
1315 err = PTR_ERR(svsk);
1316 goto out;
1317 }
1318 salen = kernel_getsockname(svsk->sk_sock, sin);
1319 if (salen >= 0)
1320 svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1321 svsk->sk_xprt.xpt_cred = get_cred(cred);
1322 svc_add_new_perm_xprt(serv, &svsk->sk_xprt);
1323 return svc_one_sock_name(svsk, name_return, len);
1324out:
1325 sockfd_put(so);
1326 return err;
1327}
1328EXPORT_SYMBOL_GPL(svc_addsock);
1329
1330/*
1331 * Create socket for RPC service.
1332 */
1333static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1334 int protocol,
1335 struct net *net,
1336 struct sockaddr *sin, int len,
1337 int flags)
1338{
1339 struct svc_sock *svsk;
1340 struct socket *sock;
1341 int error;
1342 int type;
1343 struct sockaddr_storage addr;
1344 struct sockaddr *newsin = (struct sockaddr *)&addr;
1345 int newlen;
1346 int family;
1347
1348 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1349 printk(KERN_WARNING "svc: only UDP and TCP "
1350 "sockets supported\n");
1351 return ERR_PTR(-EINVAL);
1352 }
1353
1354 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1355 switch (sin->sa_family) {
1356 case AF_INET6:
1357 family = PF_INET6;
1358 break;
1359 case AF_INET:
1360 family = PF_INET;
1361 break;
1362 default:
1363 return ERR_PTR(-EINVAL);
1364 }
1365
1366 error = __sock_create(net, family, type, protocol, &sock, 1);
1367 if (error < 0)
1368 return ERR_PTR(error);
1369
1370 svc_reclassify_socket(sock);
1371
1372 /*
1373 * If this is an PF_INET6 listener, we want to avoid
1374 * getting requests from IPv4 remotes. Those should
1375 * be shunted to a PF_INET listener via rpcbind.
1376 */
1377 if (family == PF_INET6)
1378 ip6_sock_set_v6only(sock->sk);
1379 if (type == SOCK_STREAM)
1380 sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
1381 error = kernel_bind(sock, sin, len);
1382 if (error < 0)
1383 goto bummer;
1384
1385 error = kernel_getsockname(sock, newsin);
1386 if (error < 0)
1387 goto bummer;
1388 newlen = error;
1389
1390 if (protocol == IPPROTO_TCP) {
1391 if ((error = kernel_listen(sock, 64)) < 0)
1392 goto bummer;
1393 }
1394
1395 svsk = svc_setup_socket(serv, sock, flags);
1396 if (IS_ERR(svsk)) {
1397 error = PTR_ERR(svsk);
1398 goto bummer;
1399 }
1400 svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1401 return (struct svc_xprt *)svsk;
1402bummer:
1403 sock_release(sock);
1404 return ERR_PTR(error);
1405}
1406
1407/*
1408 * Detach the svc_sock from the socket so that no
1409 * more callbacks occur.
1410 */
1411static void svc_sock_detach(struct svc_xprt *xprt)
1412{
1413 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1414 struct sock *sk = svsk->sk_sk;
1415
1416 /* put back the old socket callbacks */
1417 lock_sock(sk);
1418 sk->sk_state_change = svsk->sk_ostate;
1419 sk->sk_data_ready = svsk->sk_odata;
1420 sk->sk_write_space = svsk->sk_owspace;
1421 sk->sk_user_data = NULL;
1422 release_sock(sk);
1423}
1424
1425/*
1426 * Disconnect the socket, and reset the callbacks
1427 */
1428static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1429{
1430 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1431
1432 svc_sock_detach(xprt);
1433
1434 if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1435 svc_tcp_clear_pages(svsk);
1436 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1437 }
1438}
1439
1440/*
1441 * Free the svc_sock's socket resources and the svc_sock itself.
1442 */
1443static void svc_sock_free(struct svc_xprt *xprt)
1444{
1445 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1446
1447 if (svsk->sk_sock->file)
1448 sockfd_put(svsk->sk_sock);
1449 else
1450 sock_release(svsk->sk_sock);
1451 kfree(svsk);
1452}
1/*
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_xprt_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/kernel.h>
23#include <linux/sched.h>
24#include <linux/errno.h>
25#include <linux/fcntl.h>
26#include <linux/net.h>
27#include <linux/in.h>
28#include <linux/inet.h>
29#include <linux/udp.h>
30#include <linux/tcp.h>
31#include <linux/unistd.h>
32#include <linux/slab.h>
33#include <linux/netdevice.h>
34#include <linux/skbuff.h>
35#include <linux/file.h>
36#include <linux/freezer.h>
37#include <net/sock.h>
38#include <net/checksum.h>
39#include <net/ip.h>
40#include <net/ipv6.h>
41#include <net/tcp.h>
42#include <net/tcp_states.h>
43#include <asm/uaccess.h>
44#include <asm/ioctls.h>
45
46#include <linux/sunrpc/types.h>
47#include <linux/sunrpc/clnt.h>
48#include <linux/sunrpc/xdr.h>
49#include <linux/sunrpc/msg_prot.h>
50#include <linux/sunrpc/svcsock.h>
51#include <linux/sunrpc/stats.h>
52#include <linux/sunrpc/xprt.h>
53
54#include "sunrpc.h"
55
56#define RPCDBG_FACILITY RPCDBG_SVCXPRT
57
58
59static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
60 int *errp, int flags);
61static void svc_udp_data_ready(struct sock *, int);
62static int svc_udp_recvfrom(struct svc_rqst *);
63static int svc_udp_sendto(struct svc_rqst *);
64static void svc_sock_detach(struct svc_xprt *);
65static void svc_tcp_sock_detach(struct svc_xprt *);
66static void svc_sock_free(struct svc_xprt *);
67
68static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
69 struct net *, struct sockaddr *,
70 int, int);
71#if defined(CONFIG_SUNRPC_BACKCHANNEL)
72static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
73 struct net *, struct sockaddr *,
74 int, int);
75static void svc_bc_sock_free(struct svc_xprt *xprt);
76#endif /* CONFIG_SUNRPC_BACKCHANNEL */
77
78#ifdef CONFIG_DEBUG_LOCK_ALLOC
79static struct lock_class_key svc_key[2];
80static struct lock_class_key svc_slock_key[2];
81
82static void svc_reclassify_socket(struct socket *sock)
83{
84 struct sock *sk = sock->sk;
85 BUG_ON(sock_owned_by_user(sk));
86 switch (sk->sk_family) {
87 case AF_INET:
88 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
89 &svc_slock_key[0],
90 "sk_xprt.xpt_lock-AF_INET-NFSD",
91 &svc_key[0]);
92 break;
93
94 case AF_INET6:
95 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
96 &svc_slock_key[1],
97 "sk_xprt.xpt_lock-AF_INET6-NFSD",
98 &svc_key[1]);
99 break;
100
101 default:
102 BUG();
103 }
104}
105#else
106static void svc_reclassify_socket(struct socket *sock)
107{
108}
109#endif
110
111/*
112 * Release an skbuff after use
113 */
114static void svc_release_skb(struct svc_rqst *rqstp)
115{
116 struct sk_buff *skb = rqstp->rq_xprt_ctxt;
117
118 if (skb) {
119 struct svc_sock *svsk =
120 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
121 rqstp->rq_xprt_ctxt = NULL;
122
123 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
124 skb_free_datagram_locked(svsk->sk_sk, skb);
125 }
126}
127
128union svc_pktinfo_u {
129 struct in_pktinfo pkti;
130 struct in6_pktinfo pkti6;
131};
132#define SVC_PKTINFO_SPACE \
133 CMSG_SPACE(sizeof(union svc_pktinfo_u))
134
135static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
136{
137 struct svc_sock *svsk =
138 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
139 switch (svsk->sk_sk->sk_family) {
140 case AF_INET: {
141 struct in_pktinfo *pki = CMSG_DATA(cmh);
142
143 cmh->cmsg_level = SOL_IP;
144 cmh->cmsg_type = IP_PKTINFO;
145 pki->ipi_ifindex = 0;
146 pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr;
147 cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
148 }
149 break;
150
151 case AF_INET6: {
152 struct in6_pktinfo *pki = CMSG_DATA(cmh);
153
154 cmh->cmsg_level = SOL_IPV6;
155 cmh->cmsg_type = IPV6_PKTINFO;
156 pki->ipi6_ifindex = 0;
157 ipv6_addr_copy(&pki->ipi6_addr,
158 &rqstp->rq_daddr.addr6);
159 cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
160 }
161 break;
162 }
163}
164
165/*
166 * send routine intended to be shared by the fore- and back-channel
167 */
168int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
169 struct page *headpage, unsigned long headoffset,
170 struct page *tailpage, unsigned long tailoffset)
171{
172 int result;
173 int size;
174 struct page **ppage = xdr->pages;
175 size_t base = xdr->page_base;
176 unsigned int pglen = xdr->page_len;
177 unsigned int flags = MSG_MORE;
178 int slen;
179 int len = 0;
180
181 slen = xdr->len;
182
183 /* send head */
184 if (slen == xdr->head[0].iov_len)
185 flags = 0;
186 len = kernel_sendpage(sock, headpage, headoffset,
187 xdr->head[0].iov_len, flags);
188 if (len != xdr->head[0].iov_len)
189 goto out;
190 slen -= xdr->head[0].iov_len;
191 if (slen == 0)
192 goto out;
193
194 /* send page data */
195 size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
196 while (pglen > 0) {
197 if (slen == size)
198 flags = 0;
199 result = kernel_sendpage(sock, *ppage, base, size, flags);
200 if (result > 0)
201 len += result;
202 if (result != size)
203 goto out;
204 slen -= size;
205 pglen -= size;
206 size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
207 base = 0;
208 ppage++;
209 }
210
211 /* send tail */
212 if (xdr->tail[0].iov_len) {
213 result = kernel_sendpage(sock, tailpage, tailoffset,
214 xdr->tail[0].iov_len, 0);
215 if (result > 0)
216 len += result;
217 }
218
219out:
220 return len;
221}
222
223
224/*
225 * Generic sendto routine
226 */
227static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
228{
229 struct svc_sock *svsk =
230 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
231 struct socket *sock = svsk->sk_sock;
232 union {
233 struct cmsghdr hdr;
234 long all[SVC_PKTINFO_SPACE / sizeof(long)];
235 } buffer;
236 struct cmsghdr *cmh = &buffer.hdr;
237 int len = 0;
238 unsigned long tailoff;
239 unsigned long headoff;
240 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
241
242 if (rqstp->rq_prot == IPPROTO_UDP) {
243 struct msghdr msg = {
244 .msg_name = &rqstp->rq_addr,
245 .msg_namelen = rqstp->rq_addrlen,
246 .msg_control = cmh,
247 .msg_controllen = sizeof(buffer),
248 .msg_flags = MSG_MORE,
249 };
250
251 svc_set_cmsg_data(rqstp, cmh);
252
253 if (sock_sendmsg(sock, &msg, 0) < 0)
254 goto out;
255 }
256
257 tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
258 headoff = 0;
259 len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
260 rqstp->rq_respages[0], tailoff);
261
262out:
263 dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
264 svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
265 xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
266
267 return len;
268}
269
270/*
271 * Report socket names for nfsdfs
272 */
273static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
274{
275 const struct sock *sk = svsk->sk_sk;
276 const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
277 "udp" : "tcp";
278 int len;
279
280 switch (sk->sk_family) {
281 case PF_INET:
282 len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
283 proto_name,
284 &inet_sk(sk)->inet_rcv_saddr,
285 inet_sk(sk)->inet_num);
286 break;
287 case PF_INET6:
288 len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
289 proto_name,
290 &inet6_sk(sk)->rcv_saddr,
291 inet_sk(sk)->inet_num);
292 break;
293 default:
294 len = snprintf(buf, remaining, "*unknown-%d*\n",
295 sk->sk_family);
296 }
297
298 if (len >= remaining) {
299 *buf = '\0';
300 return -ENAMETOOLONG;
301 }
302 return len;
303}
304
305/**
306 * svc_sock_names - construct a list of listener names in a string
307 * @serv: pointer to RPC service
308 * @buf: pointer to a buffer to fill in with socket names
309 * @buflen: size of the buffer to be filled
310 * @toclose: pointer to '\0'-terminated C string containing the name
311 * of a listener to be closed
312 *
313 * Fills in @buf with a '\n'-separated list of names of listener
314 * sockets. If @toclose is not NULL, the socket named by @toclose
315 * is closed, and is not included in the output list.
316 *
317 * Returns positive length of the socket name string, or a negative
318 * errno value on error.
319 */
320int svc_sock_names(struct svc_serv *serv, char *buf, const size_t buflen,
321 const char *toclose)
322{
323 struct svc_sock *svsk, *closesk = NULL;
324 int len = 0;
325
326 if (!serv)
327 return 0;
328
329 spin_lock_bh(&serv->sv_lock);
330 list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
331 int onelen = svc_one_sock_name(svsk, buf + len, buflen - len);
332 if (onelen < 0) {
333 len = onelen;
334 break;
335 }
336 if (toclose && strcmp(toclose, buf + len) == 0) {
337 closesk = svsk;
338 svc_xprt_get(&closesk->sk_xprt);
339 } else
340 len += onelen;
341 }
342 spin_unlock_bh(&serv->sv_lock);
343
344 if (closesk) {
345 /* Should unregister with portmap, but you cannot
346 * unregister just one protocol...
347 */
348 svc_close_xprt(&closesk->sk_xprt);
349 svc_xprt_put(&closesk->sk_xprt);
350 } else if (toclose)
351 return -ENOENT;
352 return len;
353}
354EXPORT_SYMBOL_GPL(svc_sock_names);
355
356/*
357 * Check input queue length
358 */
359static int svc_recv_available(struct svc_sock *svsk)
360{
361 struct socket *sock = svsk->sk_sock;
362 int avail, err;
363
364 err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
365
366 return (err >= 0)? avail : err;
367}
368
369/*
370 * Generic recvfrom routine.
371 */
372static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
373 int buflen)
374{
375 struct svc_sock *svsk =
376 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
377 struct msghdr msg = {
378 .msg_flags = MSG_DONTWAIT,
379 };
380 int len;
381
382 rqstp->rq_xprt_hlen = 0;
383
384 len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
385 msg.msg_flags);
386
387 dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
388 svsk, iov[0].iov_base, iov[0].iov_len, len);
389 return len;
390}
391
392static int svc_partial_recvfrom(struct svc_rqst *rqstp,
393 struct kvec *iov, int nr,
394 int buflen, unsigned int base)
395{
396 size_t save_iovlen;
397 void __user *save_iovbase;
398 unsigned int i;
399 int ret;
400
401 if (base == 0)
402 return svc_recvfrom(rqstp, iov, nr, buflen);
403
404 for (i = 0; i < nr; i++) {
405 if (iov[i].iov_len > base)
406 break;
407 base -= iov[i].iov_len;
408 }
409 save_iovlen = iov[i].iov_len;
410 save_iovbase = iov[i].iov_base;
411 iov[i].iov_len -= base;
412 iov[i].iov_base += base;
413 ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
414 iov[i].iov_len = save_iovlen;
415 iov[i].iov_base = save_iovbase;
416 return ret;
417}
418
419/*
420 * Set socket snd and rcv buffer lengths
421 */
422static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
423 unsigned int rcv)
424{
425#if 0
426 mm_segment_t oldfs;
427 oldfs = get_fs(); set_fs(KERNEL_DS);
428 sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
429 (char*)&snd, sizeof(snd));
430 sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
431 (char*)&rcv, sizeof(rcv));
432#else
433 /* sock_setsockopt limits use to sysctl_?mem_max,
434 * which isn't acceptable. Until that is made conditional
435 * on not having CAP_SYS_RESOURCE or similar, we go direct...
436 * DaveM said I could!
437 */
438 lock_sock(sock->sk);
439 sock->sk->sk_sndbuf = snd * 2;
440 sock->sk->sk_rcvbuf = rcv * 2;
441 sock->sk->sk_write_space(sock->sk);
442 release_sock(sock->sk);
443#endif
444}
445/*
446 * INET callback when data has been received on the socket.
447 */
448static void svc_udp_data_ready(struct sock *sk, int count)
449{
450 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
451 wait_queue_head_t *wq = sk_sleep(sk);
452
453 if (svsk) {
454 dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
455 svsk, sk, count,
456 test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
457 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
458 svc_xprt_enqueue(&svsk->sk_xprt);
459 }
460 if (wq && waitqueue_active(wq))
461 wake_up_interruptible(wq);
462}
463
464/*
465 * INET callback when space is newly available on the socket.
466 */
467static void svc_write_space(struct sock *sk)
468{
469 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
470 wait_queue_head_t *wq = sk_sleep(sk);
471
472 if (svsk) {
473 dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
474 svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
475 svc_xprt_enqueue(&svsk->sk_xprt);
476 }
477
478 if (wq && waitqueue_active(wq)) {
479 dprintk("RPC svc_write_space: someone sleeping on %p\n",
480 svsk);
481 wake_up_interruptible(wq);
482 }
483}
484
485static void svc_tcp_write_space(struct sock *sk)
486{
487 struct socket *sock = sk->sk_socket;
488
489 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock)
490 clear_bit(SOCK_NOSPACE, &sock->flags);
491 svc_write_space(sk);
492}
493
494/*
495 * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
496 */
497static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
498 struct cmsghdr *cmh)
499{
500 struct in_pktinfo *pki = CMSG_DATA(cmh);
501 if (cmh->cmsg_type != IP_PKTINFO)
502 return 0;
503 rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr;
504 return 1;
505}
506
507/*
508 * See net/ipv6/datagram.c : datagram_recv_ctl
509 */
510static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
511 struct cmsghdr *cmh)
512{
513 struct in6_pktinfo *pki = CMSG_DATA(cmh);
514 if (cmh->cmsg_type != IPV6_PKTINFO)
515 return 0;
516 ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr);
517 return 1;
518}
519
520/*
521 * Copy the UDP datagram's destination address to the rqstp structure.
522 * The 'destination' address in this case is the address to which the
523 * peer sent the datagram, i.e. our local address. For multihomed
524 * hosts, this can change from msg to msg. Note that only the IP
525 * address changes, the port number should remain the same.
526 */
527static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
528 struct cmsghdr *cmh)
529{
530 switch (cmh->cmsg_level) {
531 case SOL_IP:
532 return svc_udp_get_dest_address4(rqstp, cmh);
533 case SOL_IPV6:
534 return svc_udp_get_dest_address6(rqstp, cmh);
535 }
536
537 return 0;
538}
539
540/*
541 * Receive a datagram from a UDP socket.
542 */
543static int svc_udp_recvfrom(struct svc_rqst *rqstp)
544{
545 struct svc_sock *svsk =
546 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
547 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
548 struct sk_buff *skb;
549 union {
550 struct cmsghdr hdr;
551 long all[SVC_PKTINFO_SPACE / sizeof(long)];
552 } buffer;
553 struct cmsghdr *cmh = &buffer.hdr;
554 struct msghdr msg = {
555 .msg_name = svc_addr(rqstp),
556 .msg_control = cmh,
557 .msg_controllen = sizeof(buffer),
558 .msg_flags = MSG_DONTWAIT,
559 };
560 size_t len;
561 int err;
562
563 if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
564 /* udp sockets need large rcvbuf as all pending
565 * requests are still in that buffer. sndbuf must
566 * also be large enough that there is enough space
567 * for one reply per thread. We count all threads
568 * rather than threads in a particular pool, which
569 * provides an upper bound on the number of threads
570 * which will access the socket.
571 */
572 svc_sock_setbufsize(svsk->sk_sock,
573 (serv->sv_nrthreads+3) * serv->sv_max_mesg,
574 (serv->sv_nrthreads+3) * serv->sv_max_mesg);
575
576 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
577 skb = NULL;
578 err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
579 0, 0, MSG_PEEK | MSG_DONTWAIT);
580 if (err >= 0)
581 skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
582
583 if (skb == NULL) {
584 if (err != -EAGAIN) {
585 /* possibly an icmp error */
586 dprintk("svc: recvfrom returned error %d\n", -err);
587 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
588 }
589 return -EAGAIN;
590 }
591 len = svc_addr_len(svc_addr(rqstp));
592 if (len == 0)
593 return -EAFNOSUPPORT;
594 rqstp->rq_addrlen = len;
595 if (skb->tstamp.tv64 == 0) {
596 skb->tstamp = ktime_get_real();
597 /* Don't enable netstamp, sunrpc doesn't
598 need that much accuracy */
599 }
600 svsk->sk_sk->sk_stamp = skb->tstamp;
601 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
602
603 len = skb->len - sizeof(struct udphdr);
604 rqstp->rq_arg.len = len;
605
606 rqstp->rq_prot = IPPROTO_UDP;
607
608 if (!svc_udp_get_dest_address(rqstp, cmh)) {
609 if (net_ratelimit())
610 printk(KERN_WARNING
611 "svc: received unknown control message %d/%d; "
612 "dropping RPC reply datagram\n",
613 cmh->cmsg_level, cmh->cmsg_type);
614 skb_free_datagram_locked(svsk->sk_sk, skb);
615 return 0;
616 }
617
618 if (skb_is_nonlinear(skb)) {
619 /* we have to copy */
620 local_bh_disable();
621 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
622 local_bh_enable();
623 /* checksum error */
624 skb_free_datagram_locked(svsk->sk_sk, skb);
625 return 0;
626 }
627 local_bh_enable();
628 skb_free_datagram_locked(svsk->sk_sk, skb);
629 } else {
630 /* we can use it in-place */
631 rqstp->rq_arg.head[0].iov_base = skb->data +
632 sizeof(struct udphdr);
633 rqstp->rq_arg.head[0].iov_len = len;
634 if (skb_checksum_complete(skb)) {
635 skb_free_datagram_locked(svsk->sk_sk, skb);
636 return 0;
637 }
638 rqstp->rq_xprt_ctxt = skb;
639 }
640
641 rqstp->rq_arg.page_base = 0;
642 if (len <= rqstp->rq_arg.head[0].iov_len) {
643 rqstp->rq_arg.head[0].iov_len = len;
644 rqstp->rq_arg.page_len = 0;
645 rqstp->rq_respages = rqstp->rq_pages+1;
646 } else {
647 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
648 rqstp->rq_respages = rqstp->rq_pages + 1 +
649 DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
650 }
651
652 if (serv->sv_stats)
653 serv->sv_stats->netudpcnt++;
654
655 return len;
656}
657
658static int
659svc_udp_sendto(struct svc_rqst *rqstp)
660{
661 int error;
662
663 error = svc_sendto(rqstp, &rqstp->rq_res);
664 if (error == -ECONNREFUSED)
665 /* ICMP error on earlier request. */
666 error = svc_sendto(rqstp, &rqstp->rq_res);
667
668 return error;
669}
670
671static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
672{
673}
674
675static int svc_udp_has_wspace(struct svc_xprt *xprt)
676{
677 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
678 struct svc_serv *serv = xprt->xpt_server;
679 unsigned long required;
680
681 /*
682 * Set the SOCK_NOSPACE flag before checking the available
683 * sock space.
684 */
685 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
686 required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
687 if (required*2 > sock_wspace(svsk->sk_sk))
688 return 0;
689 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
690 return 1;
691}
692
693static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
694{
695 BUG();
696 return NULL;
697}
698
699static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
700 struct net *net,
701 struct sockaddr *sa, int salen,
702 int flags)
703{
704 return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
705}
706
707static struct svc_xprt_ops svc_udp_ops = {
708 .xpo_create = svc_udp_create,
709 .xpo_recvfrom = svc_udp_recvfrom,
710 .xpo_sendto = svc_udp_sendto,
711 .xpo_release_rqst = svc_release_skb,
712 .xpo_detach = svc_sock_detach,
713 .xpo_free = svc_sock_free,
714 .xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
715 .xpo_has_wspace = svc_udp_has_wspace,
716 .xpo_accept = svc_udp_accept,
717};
718
719static struct svc_xprt_class svc_udp_class = {
720 .xcl_name = "udp",
721 .xcl_owner = THIS_MODULE,
722 .xcl_ops = &svc_udp_ops,
723 .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
724};
725
726static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
727{
728 int err, level, optname, one = 1;
729
730 svc_xprt_init(&svc_udp_class, &svsk->sk_xprt, serv);
731 clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
732 svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
733 svsk->sk_sk->sk_write_space = svc_write_space;
734
735 /* initialise setting must have enough space to
736 * receive and respond to one request.
737 * svc_udp_recvfrom will re-adjust if necessary
738 */
739 svc_sock_setbufsize(svsk->sk_sock,
740 3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
741 3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
742
743 /* data might have come in before data_ready set up */
744 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
745 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
746
747 /* make sure we get destination address info */
748 switch (svsk->sk_sk->sk_family) {
749 case AF_INET:
750 level = SOL_IP;
751 optname = IP_PKTINFO;
752 break;
753 case AF_INET6:
754 level = SOL_IPV6;
755 optname = IPV6_RECVPKTINFO;
756 break;
757 default:
758 BUG();
759 }
760 err = kernel_setsockopt(svsk->sk_sock, level, optname,
761 (char *)&one, sizeof(one));
762 dprintk("svc: kernel_setsockopt returned %d\n", err);
763}
764
765/*
766 * A data_ready event on a listening socket means there's a connection
767 * pending. Do not use state_change as a substitute for it.
768 */
769static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
770{
771 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
772 wait_queue_head_t *wq;
773
774 dprintk("svc: socket %p TCP (listen) state change %d\n",
775 sk, sk->sk_state);
776
777 /*
778 * This callback may called twice when a new connection
779 * is established as a child socket inherits everything
780 * from a parent LISTEN socket.
781 * 1) data_ready method of the parent socket will be called
782 * when one of child sockets become ESTABLISHED.
783 * 2) data_ready method of the child socket may be called
784 * when it receives data before the socket is accepted.
785 * In case of 2, we should ignore it silently.
786 */
787 if (sk->sk_state == TCP_LISTEN) {
788 if (svsk) {
789 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
790 svc_xprt_enqueue(&svsk->sk_xprt);
791 } else
792 printk("svc: socket %p: no user data\n", sk);
793 }
794
795 wq = sk_sleep(sk);
796 if (wq && waitqueue_active(wq))
797 wake_up_interruptible_all(wq);
798}
799
800/*
801 * A state change on a connected socket means it's dying or dead.
802 */
803static void svc_tcp_state_change(struct sock *sk)
804{
805 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
806 wait_queue_head_t *wq = sk_sleep(sk);
807
808 dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
809 sk, sk->sk_state, sk->sk_user_data);
810
811 if (!svsk)
812 printk("svc: socket %p: no user data\n", sk);
813 else {
814 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
815 svc_xprt_enqueue(&svsk->sk_xprt);
816 }
817 if (wq && waitqueue_active(wq))
818 wake_up_interruptible_all(wq);
819}
820
821static void svc_tcp_data_ready(struct sock *sk, int count)
822{
823 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
824 wait_queue_head_t *wq = sk_sleep(sk);
825
826 dprintk("svc: socket %p TCP data ready (svsk %p)\n",
827 sk, sk->sk_user_data);
828 if (svsk) {
829 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
830 svc_xprt_enqueue(&svsk->sk_xprt);
831 }
832 if (wq && waitqueue_active(wq))
833 wake_up_interruptible(wq);
834}
835
836/*
837 * Accept a TCP connection
838 */
839static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
840{
841 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
842 struct sockaddr_storage addr;
843 struct sockaddr *sin = (struct sockaddr *) &addr;
844 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
845 struct socket *sock = svsk->sk_sock;
846 struct socket *newsock;
847 struct svc_sock *newsvsk;
848 int err, slen;
849 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
850
851 dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
852 if (!sock)
853 return NULL;
854
855 clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
856 err = kernel_accept(sock, &newsock, O_NONBLOCK);
857 if (err < 0) {
858 if (err == -ENOMEM)
859 printk(KERN_WARNING "%s: no more sockets!\n",
860 serv->sv_name);
861 else if (err != -EAGAIN && net_ratelimit())
862 printk(KERN_WARNING "%s: accept failed (err %d)!\n",
863 serv->sv_name, -err);
864 return NULL;
865 }
866 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
867
868 err = kernel_getpeername(newsock, sin, &slen);
869 if (err < 0) {
870 if (net_ratelimit())
871 printk(KERN_WARNING "%s: peername failed (err %d)!\n",
872 serv->sv_name, -err);
873 goto failed; /* aborted connection or whatever */
874 }
875
876 /* Ideally, we would want to reject connections from unauthorized
877 * hosts here, but when we get encryption, the IP of the host won't
878 * tell us anything. For now just warn about unpriv connections.
879 */
880 if (!svc_port_is_privileged(sin)) {
881 dprintk(KERN_WARNING
882 "%s: connect from unprivileged port: %s\n",
883 serv->sv_name,
884 __svc_print_addr(sin, buf, sizeof(buf)));
885 }
886 dprintk("%s: connect from %s\n", serv->sv_name,
887 __svc_print_addr(sin, buf, sizeof(buf)));
888
889 /* make sure that a write doesn't block forever when
890 * low on memory
891 */
892 newsock->sk->sk_sndtimeo = HZ*30;
893
894 if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
895 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
896 goto failed;
897 svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
898 err = kernel_getsockname(newsock, sin, &slen);
899 if (unlikely(err < 0)) {
900 dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
901 slen = offsetof(struct sockaddr, sa_data);
902 }
903 svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
904
905 if (serv->sv_stats)
906 serv->sv_stats->nettcpconn++;
907
908 return &newsvsk->sk_xprt;
909
910failed:
911 sock_release(newsock);
912 return NULL;
913}
914
915static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
916{
917 unsigned int i, len, npages;
918
919 if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
920 return 0;
921 len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
922 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
923 for (i = 0; i < npages; i++) {
924 if (rqstp->rq_pages[i] != NULL)
925 put_page(rqstp->rq_pages[i]);
926 BUG_ON(svsk->sk_pages[i] == NULL);
927 rqstp->rq_pages[i] = svsk->sk_pages[i];
928 svsk->sk_pages[i] = NULL;
929 }
930 rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
931 return len;
932}
933
934static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
935{
936 unsigned int i, len, npages;
937
938 if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
939 return;
940 len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
941 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
942 for (i = 0; i < npages; i++) {
943 svsk->sk_pages[i] = rqstp->rq_pages[i];
944 rqstp->rq_pages[i] = NULL;
945 }
946}
947
948static void svc_tcp_clear_pages(struct svc_sock *svsk)
949{
950 unsigned int i, len, npages;
951
952 if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
953 goto out;
954 len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
955 npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
956 for (i = 0; i < npages; i++) {
957 BUG_ON(svsk->sk_pages[i] == NULL);
958 put_page(svsk->sk_pages[i]);
959 svsk->sk_pages[i] = NULL;
960 }
961out:
962 svsk->sk_tcplen = 0;
963}
964
965/*
966 * Receive data.
967 * If we haven't gotten the record length yet, get the next four bytes.
968 * Otherwise try to gobble up as much as possible up to the complete
969 * record length.
970 */
971static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
972{
973 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
974 unsigned int want;
975 int len;
976
977 clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
978
979 if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
980 struct kvec iov;
981
982 want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
983 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
984 iov.iov_len = want;
985 if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
986 goto error;
987 svsk->sk_tcplen += len;
988
989 if (len < want) {
990 dprintk("svc: short recvfrom while reading record "
991 "length (%d of %d)\n", len, want);
992 return -EAGAIN;
993 }
994
995 svsk->sk_reclen = ntohl(svsk->sk_reclen);
996 if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
997 /* FIXME: technically, a record can be fragmented,
998 * and non-terminal fragments will not have the top
999 * bit set in the fragment length header.
1000 * But apparently no known nfs clients send fragmented
1001 * records. */
1002 if (net_ratelimit())
1003 printk(KERN_NOTICE "RPC: multiple fragments "
1004 "per record not supported\n");
1005 goto err_delete;
1006 }
1007
1008 svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
1009 dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
1010 if (svsk->sk_reclen > serv->sv_max_mesg) {
1011 if (net_ratelimit())
1012 printk(KERN_NOTICE "RPC: "
1013 "fragment too large: 0x%08lx\n",
1014 (unsigned long)svsk->sk_reclen);
1015 goto err_delete;
1016 }
1017 }
1018
1019 if (svsk->sk_reclen < 8)
1020 goto err_delete; /* client is nuts. */
1021
1022 len = svsk->sk_reclen;
1023
1024 return len;
1025error:
1026 dprintk("RPC: TCP recv_record got %d\n", len);
1027 return len;
1028err_delete:
1029 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1030 return -EAGAIN;
1031}
1032
1033static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
1034{
1035 struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
1036 struct rpc_rqst *req = NULL;
1037 struct kvec *src, *dst;
1038 __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1039 __be32 xid;
1040 __be32 calldir;
1041
1042 xid = *p++;
1043 calldir = *p;
1044
1045 if (bc_xprt)
1046 req = xprt_lookup_rqst(bc_xprt, xid);
1047
1048 if (!req) {
1049 printk(KERN_NOTICE
1050 "%s: Got unrecognized reply: "
1051 "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
1052 __func__, ntohl(calldir),
1053 bc_xprt, xid);
1054 return -EAGAIN;
1055 }
1056
1057 memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
1058 /*
1059 * XXX!: cheating for now! Only copying HEAD.
1060 * But we know this is good enough for now (in fact, for any
1061 * callback reply in the forseeable future).
1062 */
1063 dst = &req->rq_private_buf.head[0];
1064 src = &rqstp->rq_arg.head[0];
1065 if (dst->iov_len < src->iov_len)
1066 return -EAGAIN; /* whatever; just giving up. */
1067 memcpy(dst->iov_base, src->iov_base, src->iov_len);
1068 xprt_complete_rqst(req->rq_task, svsk->sk_reclen);
1069 rqstp->rq_arg.len = 0;
1070 return 0;
1071}
1072
1073static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1074{
1075 int i = 0;
1076 int t = 0;
1077
1078 while (t < len) {
1079 vec[i].iov_base = page_address(pages[i]);
1080 vec[i].iov_len = PAGE_SIZE;
1081 i++;
1082 t += PAGE_SIZE;
1083 }
1084 return i;
1085}
1086
1087
1088/*
1089 * Receive data from a TCP socket.
1090 */
1091static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1092{
1093 struct svc_sock *svsk =
1094 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1095 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1096 int len;
1097 struct kvec *vec;
1098 unsigned int want, base;
1099 __be32 *p;
1100 __be32 calldir;
1101 int pnum;
1102
1103 dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1104 svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1105 test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1106 test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1107
1108 len = svc_tcp_recv_record(svsk, rqstp);
1109 if (len < 0)
1110 goto error;
1111
1112 base = svc_tcp_restore_pages(svsk, rqstp);
1113 want = svsk->sk_reclen - base;
1114
1115 vec = rqstp->rq_vec;
1116
1117 pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
1118 svsk->sk_reclen);
1119
1120 rqstp->rq_respages = &rqstp->rq_pages[pnum];
1121
1122 /* Now receive data */
1123 len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
1124 if (len >= 0)
1125 svsk->sk_tcplen += len;
1126 if (len != want) {
1127 if (len < 0 && len != -EAGAIN)
1128 goto err_other;
1129 svc_tcp_save_pages(svsk, rqstp);
1130 dprintk("svc: incomplete TCP record (%d of %d)\n",
1131 svsk->sk_tcplen, svsk->sk_reclen);
1132 goto err_noclose;
1133 }
1134
1135 rqstp->rq_arg.len = svsk->sk_reclen;
1136 rqstp->rq_arg.page_base = 0;
1137 if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1138 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1139 rqstp->rq_arg.page_len = 0;
1140 } else
1141 rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1142
1143 rqstp->rq_xprt_ctxt = NULL;
1144 rqstp->rq_prot = IPPROTO_TCP;
1145
1146 p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1147 calldir = p[1];
1148 if (calldir)
1149 len = receive_cb_reply(svsk, rqstp);
1150
1151 /* Reset TCP read info */
1152 svsk->sk_reclen = 0;
1153 svsk->sk_tcplen = 0;
1154 /* If we have more data, signal svc_xprt_enqueue() to try again */
1155 if (svc_recv_available(svsk) > sizeof(rpc_fraghdr))
1156 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1157
1158 if (len < 0)
1159 goto error;
1160
1161 svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1162 if (serv->sv_stats)
1163 serv->sv_stats->nettcpcnt++;
1164
1165 dprintk("svc: TCP complete record (%d bytes)\n", rqstp->rq_arg.len);
1166 return rqstp->rq_arg.len;
1167
1168error:
1169 if (len != -EAGAIN)
1170 goto err_other;
1171 dprintk("RPC: TCP recvfrom got EAGAIN\n");
1172 return -EAGAIN;
1173err_other:
1174 printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1175 svsk->sk_xprt.xpt_server->sv_name, -len);
1176 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1177err_noclose:
1178 return -EAGAIN; /* record not complete */
1179}
1180
1181/*
1182 * Send out data on TCP socket.
1183 */
1184static int svc_tcp_sendto(struct svc_rqst *rqstp)
1185{
1186 struct xdr_buf *xbufp = &rqstp->rq_res;
1187 int sent;
1188 __be32 reclen;
1189
1190 /* Set up the first element of the reply kvec.
1191 * Any other kvecs that may be in use have been taken
1192 * care of by the server implementation itself.
1193 */
1194 reclen = htonl(0x80000000|((xbufp->len ) - 4));
1195 memcpy(xbufp->head[0].iov_base, &reclen, 4);
1196
1197 sent = svc_sendto(rqstp, &rqstp->rq_res);
1198 if (sent != xbufp->len) {
1199 printk(KERN_NOTICE
1200 "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1201 "- shutting down socket\n",
1202 rqstp->rq_xprt->xpt_server->sv_name,
1203 (sent<0)?"got error":"sent only",
1204 sent, xbufp->len);
1205 set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1206 svc_xprt_enqueue(rqstp->rq_xprt);
1207 sent = -EAGAIN;
1208 }
1209 return sent;
1210}
1211
1212/*
1213 * Setup response header. TCP has a 4B record length field.
1214 */
1215static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1216{
1217 struct kvec *resv = &rqstp->rq_res.head[0];
1218
1219 /* tcp needs a space for the record length... */
1220 svc_putnl(resv, 0);
1221}
1222
1223static int svc_tcp_has_wspace(struct svc_xprt *xprt)
1224{
1225 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1226 struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1227 int required;
1228
1229 if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
1230 return 1;
1231 required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
1232 if (sk_stream_wspace(svsk->sk_sk) >= required)
1233 return 1;
1234 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1235 return 0;
1236}
1237
1238static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1239 struct net *net,
1240 struct sockaddr *sa, int salen,
1241 int flags)
1242{
1243 return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1244}
1245
1246#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1247static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
1248 struct net *, struct sockaddr *,
1249 int, int);
1250static void svc_bc_sock_free(struct svc_xprt *xprt);
1251
1252static struct svc_xprt *svc_bc_tcp_create(struct svc_serv *serv,
1253 struct net *net,
1254 struct sockaddr *sa, int salen,
1255 int flags)
1256{
1257 return svc_bc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1258}
1259
1260static void svc_bc_tcp_sock_detach(struct svc_xprt *xprt)
1261{
1262}
1263
1264static struct svc_xprt_ops svc_tcp_bc_ops = {
1265 .xpo_create = svc_bc_tcp_create,
1266 .xpo_detach = svc_bc_tcp_sock_detach,
1267 .xpo_free = svc_bc_sock_free,
1268 .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1269};
1270
1271static struct svc_xprt_class svc_tcp_bc_class = {
1272 .xcl_name = "tcp-bc",
1273 .xcl_owner = THIS_MODULE,
1274 .xcl_ops = &svc_tcp_bc_ops,
1275 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1276};
1277
1278static void svc_init_bc_xprt_sock(void)
1279{
1280 svc_reg_xprt_class(&svc_tcp_bc_class);
1281}
1282
1283static void svc_cleanup_bc_xprt_sock(void)
1284{
1285 svc_unreg_xprt_class(&svc_tcp_bc_class);
1286}
1287#else /* CONFIG_SUNRPC_BACKCHANNEL */
1288static void svc_init_bc_xprt_sock(void)
1289{
1290}
1291
1292static void svc_cleanup_bc_xprt_sock(void)
1293{
1294}
1295#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1296
1297static struct svc_xprt_ops svc_tcp_ops = {
1298 .xpo_create = svc_tcp_create,
1299 .xpo_recvfrom = svc_tcp_recvfrom,
1300 .xpo_sendto = svc_tcp_sendto,
1301 .xpo_release_rqst = svc_release_skb,
1302 .xpo_detach = svc_tcp_sock_detach,
1303 .xpo_free = svc_sock_free,
1304 .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1305 .xpo_has_wspace = svc_tcp_has_wspace,
1306 .xpo_accept = svc_tcp_accept,
1307};
1308
1309static struct svc_xprt_class svc_tcp_class = {
1310 .xcl_name = "tcp",
1311 .xcl_owner = THIS_MODULE,
1312 .xcl_ops = &svc_tcp_ops,
1313 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1314};
1315
1316void svc_init_xprt_sock(void)
1317{
1318 svc_reg_xprt_class(&svc_tcp_class);
1319 svc_reg_xprt_class(&svc_udp_class);
1320 svc_init_bc_xprt_sock();
1321}
1322
1323void svc_cleanup_xprt_sock(void)
1324{
1325 svc_unreg_xprt_class(&svc_tcp_class);
1326 svc_unreg_xprt_class(&svc_udp_class);
1327 svc_cleanup_bc_xprt_sock();
1328}
1329
1330static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1331{
1332 struct sock *sk = svsk->sk_sk;
1333
1334 svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt, serv);
1335 set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1336 if (sk->sk_state == TCP_LISTEN) {
1337 dprintk("setting up TCP socket for listening\n");
1338 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1339 sk->sk_data_ready = svc_tcp_listen_data_ready;
1340 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1341 } else {
1342 dprintk("setting up TCP socket for reading\n");
1343 sk->sk_state_change = svc_tcp_state_change;
1344 sk->sk_data_ready = svc_tcp_data_ready;
1345 sk->sk_write_space = svc_tcp_write_space;
1346
1347 svsk->sk_reclen = 0;
1348 svsk->sk_tcplen = 0;
1349 memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1350
1351 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1352
1353 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1354 if (sk->sk_state != TCP_ESTABLISHED)
1355 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1356 }
1357}
1358
1359void svc_sock_update_bufs(struct svc_serv *serv)
1360{
1361 /*
1362 * The number of server threads has changed. Update
1363 * rcvbuf and sndbuf accordingly on all sockets
1364 */
1365 struct svc_sock *svsk;
1366
1367 spin_lock_bh(&serv->sv_lock);
1368 list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1369 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1370 list_for_each_entry(svsk, &serv->sv_tempsocks, sk_xprt.xpt_list)
1371 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1372 spin_unlock_bh(&serv->sv_lock);
1373}
1374EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1375
1376/*
1377 * Initialize socket for RPC use and create svc_sock struct
1378 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1379 */
1380static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1381 struct socket *sock,
1382 int *errp, int flags)
1383{
1384 struct svc_sock *svsk;
1385 struct sock *inet;
1386 int pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1387
1388 dprintk("svc: svc_setup_socket %p\n", sock);
1389 if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
1390 *errp = -ENOMEM;
1391 return NULL;
1392 }
1393
1394 inet = sock->sk;
1395
1396 /* Register socket with portmapper */
1397 if (*errp >= 0 && pmap_register)
1398 *errp = svc_register(serv, inet->sk_family, inet->sk_protocol,
1399 ntohs(inet_sk(inet)->inet_sport));
1400
1401 if (*errp < 0) {
1402 kfree(svsk);
1403 return NULL;
1404 }
1405
1406 inet->sk_user_data = svsk;
1407 svsk->sk_sock = sock;
1408 svsk->sk_sk = inet;
1409 svsk->sk_ostate = inet->sk_state_change;
1410 svsk->sk_odata = inet->sk_data_ready;
1411 svsk->sk_owspace = inet->sk_write_space;
1412
1413 /* Initialize the socket */
1414 if (sock->type == SOCK_DGRAM)
1415 svc_udp_init(svsk, serv);
1416 else {
1417 /* initialise setting must have enough space to
1418 * receive and respond to one request.
1419 */
1420 svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
1421 4 * serv->sv_max_mesg);
1422 svc_tcp_init(svsk, serv);
1423 }
1424
1425 dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1426 svsk, svsk->sk_sk);
1427
1428 return svsk;
1429}
1430
1431/**
1432 * svc_addsock - add a listener socket to an RPC service
1433 * @serv: pointer to RPC service to which to add a new listener
1434 * @fd: file descriptor of the new listener
1435 * @name_return: pointer to buffer to fill in with name of listener
1436 * @len: size of the buffer
1437 *
1438 * Fills in socket name and returns positive length of name if successful.
1439 * Name is terminated with '\n'. On error, returns a negative errno
1440 * value.
1441 */
1442int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1443 const size_t len)
1444{
1445 int err = 0;
1446 struct socket *so = sockfd_lookup(fd, &err);
1447 struct svc_sock *svsk = NULL;
1448
1449 if (!so)
1450 return err;
1451 if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1452 err = -EAFNOSUPPORT;
1453 else if (so->sk->sk_protocol != IPPROTO_TCP &&
1454 so->sk->sk_protocol != IPPROTO_UDP)
1455 err = -EPROTONOSUPPORT;
1456 else if (so->state > SS_UNCONNECTED)
1457 err = -EISCONN;
1458 else {
1459 if (!try_module_get(THIS_MODULE))
1460 err = -ENOENT;
1461 else
1462 svsk = svc_setup_socket(serv, so, &err,
1463 SVC_SOCK_DEFAULTS);
1464 if (svsk) {
1465 struct sockaddr_storage addr;
1466 struct sockaddr *sin = (struct sockaddr *)&addr;
1467 int salen;
1468 if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
1469 svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1470 clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1471 spin_lock_bh(&serv->sv_lock);
1472 list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
1473 spin_unlock_bh(&serv->sv_lock);
1474 svc_xprt_received(&svsk->sk_xprt);
1475 err = 0;
1476 } else
1477 module_put(THIS_MODULE);
1478 }
1479 if (err) {
1480 sockfd_put(so);
1481 return err;
1482 }
1483 return svc_one_sock_name(svsk, name_return, len);
1484}
1485EXPORT_SYMBOL_GPL(svc_addsock);
1486
1487/*
1488 * Create socket for RPC service.
1489 */
1490static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1491 int protocol,
1492 struct net *net,
1493 struct sockaddr *sin, int len,
1494 int flags)
1495{
1496 struct svc_sock *svsk;
1497 struct socket *sock;
1498 int error;
1499 int type;
1500 struct sockaddr_storage addr;
1501 struct sockaddr *newsin = (struct sockaddr *)&addr;
1502 int newlen;
1503 int family;
1504 int val;
1505 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1506
1507 dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1508 serv->sv_program->pg_name, protocol,
1509 __svc_print_addr(sin, buf, sizeof(buf)));
1510
1511 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1512 printk(KERN_WARNING "svc: only UDP and TCP "
1513 "sockets supported\n");
1514 return ERR_PTR(-EINVAL);
1515 }
1516
1517 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1518 switch (sin->sa_family) {
1519 case AF_INET6:
1520 family = PF_INET6;
1521 break;
1522 case AF_INET:
1523 family = PF_INET;
1524 break;
1525 default:
1526 return ERR_PTR(-EINVAL);
1527 }
1528
1529 error = __sock_create(net, family, type, protocol, &sock, 1);
1530 if (error < 0)
1531 return ERR_PTR(error);
1532
1533 svc_reclassify_socket(sock);
1534
1535 /*
1536 * If this is an PF_INET6 listener, we want to avoid
1537 * getting requests from IPv4 remotes. Those should
1538 * be shunted to a PF_INET listener via rpcbind.
1539 */
1540 val = 1;
1541 if (family == PF_INET6)
1542 kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1543 (char *)&val, sizeof(val));
1544
1545 if (type == SOCK_STREAM)
1546 sock->sk->sk_reuse = 1; /* allow address reuse */
1547 error = kernel_bind(sock, sin, len);
1548 if (error < 0)
1549 goto bummer;
1550
1551 newlen = len;
1552 error = kernel_getsockname(sock, newsin, &newlen);
1553 if (error < 0)
1554 goto bummer;
1555
1556 if (protocol == IPPROTO_TCP) {
1557 if ((error = kernel_listen(sock, 64)) < 0)
1558 goto bummer;
1559 }
1560
1561 if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
1562 svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1563 return (struct svc_xprt *)svsk;
1564 }
1565
1566bummer:
1567 dprintk("svc: svc_create_socket error = %d\n", -error);
1568 sock_release(sock);
1569 return ERR_PTR(error);
1570}
1571
1572/*
1573 * Detach the svc_sock from the socket so that no
1574 * more callbacks occur.
1575 */
1576static void svc_sock_detach(struct svc_xprt *xprt)
1577{
1578 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1579 struct sock *sk = svsk->sk_sk;
1580 wait_queue_head_t *wq;
1581
1582 dprintk("svc: svc_sock_detach(%p)\n", svsk);
1583
1584 /* put back the old socket callbacks */
1585 sk->sk_state_change = svsk->sk_ostate;
1586 sk->sk_data_ready = svsk->sk_odata;
1587 sk->sk_write_space = svsk->sk_owspace;
1588
1589 wq = sk_sleep(sk);
1590 if (wq && waitqueue_active(wq))
1591 wake_up_interruptible(wq);
1592}
1593
1594/*
1595 * Disconnect the socket, and reset the callbacks
1596 */
1597static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1598{
1599 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1600
1601 dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1602
1603 svc_sock_detach(xprt);
1604
1605 if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1606 svc_tcp_clear_pages(svsk);
1607 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1608 }
1609}
1610
1611/*
1612 * Free the svc_sock's socket resources and the svc_sock itself.
1613 */
1614static void svc_sock_free(struct svc_xprt *xprt)
1615{
1616 struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1617 dprintk("svc: svc_sock_free(%p)\n", svsk);
1618
1619 if (svsk->sk_sock->file)
1620 sockfd_put(svsk->sk_sock);
1621 else
1622 sock_release(svsk->sk_sock);
1623 kfree(svsk);
1624}
1625
1626#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1627/*
1628 * Create a back channel svc_xprt which shares the fore channel socket.
1629 */
1630static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
1631 int protocol,
1632 struct net *net,
1633 struct sockaddr *sin, int len,
1634 int flags)
1635{
1636 struct svc_sock *svsk;
1637 struct svc_xprt *xprt;
1638
1639 if (protocol != IPPROTO_TCP) {
1640 printk(KERN_WARNING "svc: only TCP sockets"
1641 " supported on shared back channel\n");
1642 return ERR_PTR(-EINVAL);
1643 }
1644
1645 svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1646 if (!svsk)
1647 return ERR_PTR(-ENOMEM);
1648
1649 xprt = &svsk->sk_xprt;
1650 svc_xprt_init(&svc_tcp_bc_class, xprt, serv);
1651
1652 serv->sv_bc_xprt = xprt;
1653
1654 return xprt;
1655}
1656
1657/*
1658 * Free a back channel svc_sock.
1659 */
1660static void svc_bc_sock_free(struct svc_xprt *xprt)
1661{
1662 if (xprt)
1663 kfree(container_of(xprt, struct svc_sock, sk_xprt));
1664}
1665#endif /* CONFIG_SUNRPC_BACKCHANNEL */