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