~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/sunrpc/svcsock.c

Version: ~ [ linux-5.3-rc8 ] ~ [ linux-5.2.13 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.71 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.142 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.191 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.191 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.73 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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/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 *);
 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;
 87 
 88         WARN_ON_ONCE(sock_owned_by_user(sk));
 89         if (sock_owned_by_user(sk))
 90                 return;
 91 
 92         switch (sk->sk_family) {
 93         case AF_INET:
 94                 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
 95                                               &svc_slock_key[0],
 96                                               "sk_xprt.xpt_lock-AF_INET-NFSD",
 97                                               &svc_key[0]);
 98                 break;
 99 
100         case AF_INET6:
101                 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
102                                               &svc_slock_key[1],
103                                               "sk_xprt.xpt_lock-AF_INET6-NFSD",
104                                               &svc_key[1]);
105                 break;
106 
107         default:
108                 BUG();
109         }
110 }
111 #else
112 static void svc_reclassify_socket(struct socket *sock)
113 {
114 }
115 #endif
116 
117 /*
118  * Release an skbuff after use
119  */
120 static void svc_release_skb(struct svc_rqst *rqstp)
121 {
122         struct sk_buff *skb = rqstp->rq_xprt_ctxt;
123 
124         if (skb) {
125                 struct svc_sock *svsk =
126                         container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
127                 rqstp->rq_xprt_ctxt = NULL;
128 
129                 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
130                 skb_free_datagram_locked(svsk->sk_sk, skb);
131         }
132 }
133 
134 union svc_pktinfo_u {
135         struct in_pktinfo pkti;
136         struct in6_pktinfo pkti6;
137 };
138 #define SVC_PKTINFO_SPACE \
139         CMSG_SPACE(sizeof(union svc_pktinfo_u))
140 
141 static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
142 {
143         struct svc_sock *svsk =
144                 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
145         switch (svsk->sk_sk->sk_family) {
146         case AF_INET: {
147                         struct in_pktinfo *pki = CMSG_DATA(cmh);
148 
149                         cmh->cmsg_level = SOL_IP;
150                         cmh->cmsg_type = IP_PKTINFO;
151                         pki->ipi_ifindex = 0;
152                         pki->ipi_spec_dst.s_addr =
153                                  svc_daddr_in(rqstp)->sin_addr.s_addr;
154                         cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
155                 }
156                 break;
157 
158         case AF_INET6: {
159                         struct in6_pktinfo *pki = CMSG_DATA(cmh);
160                         struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
161 
162                         cmh->cmsg_level = SOL_IPV6;
163                         cmh->cmsg_type = IPV6_PKTINFO;
164                         pki->ipi6_ifindex = daddr->sin6_scope_id;
165                         pki->ipi6_addr = daddr->sin6_addr;
166                         cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
167                 }
168                 break;
169         }
170 }
171 
172 /*
173  * send routine intended to be shared by the fore- and back-channel
174  */
175 int svc_send_common(struct socket *sock, struct xdr_buf *xdr,
176                     struct page *headpage, unsigned long headoffset,
177                     struct page *tailpage, unsigned long tailoffset)
178 {
179         int             result;
180         int             size;
181         struct page     **ppage = xdr->pages;
182         size_t          base = xdr->page_base;
183         unsigned int    pglen = xdr->page_len;
184         unsigned int    flags = MSG_MORE;
185         int             slen;
186         int             len = 0;
187 
188         slen = xdr->len;
189 
190         /* send head */
191         if (slen == xdr->head[0].iov_len)
192                 flags = 0;
193         len = kernel_sendpage(sock, headpage, headoffset,
194                                   xdr->head[0].iov_len, flags);
195         if (len != xdr->head[0].iov_len)
196                 goto out;
197         slen -= xdr->head[0].iov_len;
198         if (slen == 0)
199                 goto out;
200 
201         /* send page data */
202         size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
203         while (pglen > 0) {
204                 if (slen == size)
205                         flags = 0;
206                 result = kernel_sendpage(sock, *ppage, base, size, flags);
207                 if (result > 0)
208                         len += result;
209                 if (result != size)
210                         goto out;
211                 slen -= size;
212                 pglen -= size;
213                 size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
214                 base = 0;
215                 ppage++;
216         }
217 
218         /* send tail */
219         if (xdr->tail[0].iov_len) {
220                 result = kernel_sendpage(sock, tailpage, tailoffset,
221                                    xdr->tail[0].iov_len, 0);
222                 if (result > 0)
223                         len += result;
224         }
225 
226 out:
227         return len;
228 }
229 
230 
231 /*
232  * Generic sendto routine
233  */
234 static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
235 {
236         struct svc_sock *svsk =
237                 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
238         struct socket   *sock = svsk->sk_sock;
239         union {
240                 struct cmsghdr  hdr;
241                 long            all[SVC_PKTINFO_SPACE / sizeof(long)];
242         } buffer;
243         struct cmsghdr *cmh = &buffer.hdr;
244         int             len = 0;
245         unsigned long tailoff;
246         unsigned long headoff;
247         RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
248 
249         if (rqstp->rq_prot == IPPROTO_UDP) {
250                 struct msghdr msg = {
251                         .msg_name       = &rqstp->rq_addr,
252                         .msg_namelen    = rqstp->rq_addrlen,
253                         .msg_control    = cmh,
254                         .msg_controllen = sizeof(buffer),
255                         .msg_flags      = MSG_MORE,
256                 };
257 
258                 svc_set_cmsg_data(rqstp, cmh);
259 
260                 if (sock_sendmsg(sock, &msg) < 0)
261                         goto out;
262         }
263 
264         tailoff = ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1);
265         headoff = 0;
266         len = svc_send_common(sock, xdr, rqstp->rq_respages[0], headoff,
267                                rqstp->rq_respages[0], tailoff);
268 
269 out:
270         dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
271                 svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
272                 xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
273 
274         return len;
275 }
276 
277 /*
278  * Report socket names for nfsdfs
279  */
280 static int svc_one_sock_name(struct svc_sock *svsk, char *buf, int remaining)
281 {
282         const struct sock *sk = svsk->sk_sk;
283         const char *proto_name = sk->sk_protocol == IPPROTO_UDP ?
284                                                         "udp" : "tcp";
285         int len;
286 
287         switch (sk->sk_family) {
288         case PF_INET:
289                 len = snprintf(buf, remaining, "ipv4 %s %pI4 %d\n",
290                                 proto_name,
291                                 &inet_sk(sk)->inet_rcv_saddr,
292                                 inet_sk(sk)->inet_num);
293                 break;
294 #if IS_ENABLED(CONFIG_IPV6)
295         case PF_INET6:
296                 len = snprintf(buf, remaining, "ipv6 %s %pI6 %d\n",
297                                 proto_name,
298                                 &sk->sk_v6_rcv_saddr,
299                                 inet_sk(sk)->inet_num);
300                 break;
301 #endif
302         default:
303                 len = snprintf(buf, remaining, "*unknown-%d*\n",
304                                 sk->sk_family);
305         }
306 
307         if (len >= remaining) {
308                 *buf = '\0';
309                 return -ENAMETOOLONG;
310         }
311         return len;
312 }
313 
314 /*
315  * Generic recvfrom routine.
316  */
317 static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
318                         int buflen)
319 {
320         struct svc_sock *svsk =
321                 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
322         struct msghdr msg = {
323                 .msg_flags      = MSG_DONTWAIT,
324         };
325         int len;
326 
327         rqstp->rq_xprt_hlen = 0;
328 
329         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
330         len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
331                                 msg.msg_flags);
332         /* If we read a full record, then assume there may be more
333          * data to read (stream based sockets only!)
334          */
335         if (len == buflen)
336                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
337 
338         dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
339                 svsk, iov[0].iov_base, iov[0].iov_len, len);
340         return len;
341 }
342 
343 static int svc_partial_recvfrom(struct svc_rqst *rqstp,
344                                 struct kvec *iov, int nr,
345                                 int buflen, unsigned int base)
346 {
347         size_t save_iovlen;
348         void *save_iovbase;
349         unsigned int i;
350         int ret;
351 
352         if (base == 0)
353                 return svc_recvfrom(rqstp, iov, nr, buflen);
354 
355         for (i = 0; i < nr; i++) {
356                 if (iov[i].iov_len > base)
357                         break;
358                 base -= iov[i].iov_len;
359         }
360         save_iovlen = iov[i].iov_len;
361         save_iovbase = iov[i].iov_base;
362         iov[i].iov_len -= base;
363         iov[i].iov_base += base;
364         ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
365         iov[i].iov_len = save_iovlen;
366         iov[i].iov_base = save_iovbase;
367         return ret;
368 }
369 
370 /*
371  * Set socket snd and rcv buffer lengths
372  */
373 static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
374                                 unsigned int rcv)
375 {
376 #if 0
377         mm_segment_t    oldfs;
378         oldfs = get_fs(); set_fs(KERNEL_DS);
379         sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
380                         (char*)&snd, sizeof(snd));
381         sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
382                         (char*)&rcv, sizeof(rcv));
383 #else
384         /* sock_setsockopt limits use to sysctl_?mem_max,
385          * which isn't acceptable.  Until that is made conditional
386          * on not having CAP_SYS_RESOURCE or similar, we go direct...
387          * DaveM said I could!
388          */
389         lock_sock(sock->sk);
390         sock->sk->sk_sndbuf = snd * 2;
391         sock->sk->sk_rcvbuf = rcv * 2;
392         sock->sk->sk_write_space(sock->sk);
393         release_sock(sock->sk);
394 #endif
395 }
396 
397 static int svc_sock_secure_port(struct svc_rqst *rqstp)
398 {
399         return svc_port_is_privileged(svc_addr(rqstp));
400 }
401 
402 /*
403  * INET callback when data has been received on the socket.
404  */
405 static void svc_udp_data_ready(struct sock *sk)
406 {
407         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
408         wait_queue_head_t *wq = sk_sleep(sk);
409 
410         if (svsk) {
411                 dprintk("svc: socket %p(inet %p), busy=%d\n",
412                         svsk, sk,
413                         test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
414                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
415                 svc_xprt_enqueue(&svsk->sk_xprt);
416         }
417         if (wq && waitqueue_active(wq))
418                 wake_up_interruptible(wq);
419 }
420 
421 /*
422  * INET callback when space is newly available on the socket.
423  */
424 static void svc_write_space(struct sock *sk)
425 {
426         struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
427         wait_queue_head_t *wq = sk_sleep(sk);
428 
429         if (svsk) {
430                 dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
431                         svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
432                 svc_xprt_enqueue(&svsk->sk_xprt);
433         }
434 
435         if (wq && waitqueue_active(wq)) {
436                 dprintk("RPC svc_write_space: someone sleeping on %p\n",
437                        svsk);
438                 wake_up_interruptible(wq);
439         }
440 }
441 
442 static int svc_tcp_has_wspace(struct svc_xprt *xprt)
443 {
444         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
445         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
446         int required;
447 
448         if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
449                 return 1;
450         required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
451         if (sk_stream_wspace(svsk->sk_sk) >= required ||
452             (sk_stream_min_wspace(svsk->sk_sk) == 0 &&
453              atomic_read(&xprt->xpt_reserved) == 0))
454                 return 1;
455         set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
456         return 0;
457 }
458 
459 static void svc_tcp_write_space(struct sock *sk)
460 {
461         struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
462         struct socket *sock = sk->sk_socket;
463 
464         if (!sk_stream_is_writeable(sk) || !sock)
465                 return;
466         if (!svsk || svc_tcp_has_wspace(&svsk->sk_xprt))
467                 clear_bit(SOCK_NOSPACE, &sock->flags);
468         svc_write_space(sk);
469 }
470 
471 static void svc_tcp_adjust_wspace(struct svc_xprt *xprt)
472 {
473         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
474 
475         if (svc_tcp_has_wspace(xprt))
476                 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
477 }
478 
479 /*
480  * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo
481  */
482 static int svc_udp_get_dest_address4(struct svc_rqst *rqstp,
483                                      struct cmsghdr *cmh)
484 {
485         struct in_pktinfo *pki = CMSG_DATA(cmh);
486         struct sockaddr_in *daddr = svc_daddr_in(rqstp);
487 
488         if (cmh->cmsg_type != IP_PKTINFO)
489                 return 0;
490 
491         daddr->sin_family = AF_INET;
492         daddr->sin_addr.s_addr = pki->ipi_spec_dst.s_addr;
493         return 1;
494 }
495 
496 /*
497  * See net/ipv6/datagram.c : ip6_datagram_recv_ctl
498  */
499 static int svc_udp_get_dest_address6(struct svc_rqst *rqstp,
500                                      struct cmsghdr *cmh)
501 {
502         struct in6_pktinfo *pki = CMSG_DATA(cmh);
503         struct sockaddr_in6 *daddr = svc_daddr_in6(rqstp);
504 
505         if (cmh->cmsg_type != IPV6_PKTINFO)
506                 return 0;
507 
508         daddr->sin6_family = AF_INET6;
509         daddr->sin6_addr = pki->ipi6_addr;
510         daddr->sin6_scope_id = pki->ipi6_ifindex;
511         return 1;
512 }
513 
514 /*
515  * Copy the UDP datagram's destination address to the rqstp structure.
516  * The 'destination' address in this case is the address to which the
517  * peer sent the datagram, i.e. our local address. For multihomed
518  * hosts, this can change from msg to msg. Note that only the IP
519  * address changes, the port number should remain the same.
520  */
521 static int svc_udp_get_dest_address(struct svc_rqst *rqstp,
522                                     struct cmsghdr *cmh)
523 {
524         switch (cmh->cmsg_level) {
525         case SOL_IP:
526                 return svc_udp_get_dest_address4(rqstp, cmh);
527         case SOL_IPV6:
528                 return svc_udp_get_dest_address6(rqstp, cmh);
529         }
530 
531         return 0;
532 }
533 
534 /*
535  * Receive a datagram from a UDP socket.
536  */
537 static int svc_udp_recvfrom(struct svc_rqst *rqstp)
538 {
539         struct svc_sock *svsk =
540                 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
541         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
542         struct sk_buff  *skb;
543         union {
544                 struct cmsghdr  hdr;
545                 long            all[SVC_PKTINFO_SPACE / sizeof(long)];
546         } buffer;
547         struct cmsghdr *cmh = &buffer.hdr;
548         struct msghdr msg = {
549                 .msg_name = svc_addr(rqstp),
550                 .msg_control = cmh,
551                 .msg_controllen = sizeof(buffer),
552                 .msg_flags = MSG_DONTWAIT,
553         };
554         size_t len;
555         int err;
556 
557         if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
558             /* udp sockets need large rcvbuf as all pending
559              * requests are still in that buffer.  sndbuf must
560              * also be large enough that there is enough space
561              * for one reply per thread.  We count all threads
562              * rather than threads in a particular pool, which
563              * provides an upper bound on the number of threads
564              * which will access the socket.
565              */
566             svc_sock_setbufsize(svsk->sk_sock,
567                                 (serv->sv_nrthreads+3) * serv->sv_max_mesg,
568                                 (serv->sv_nrthreads+3) * serv->sv_max_mesg);
569 
570         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
571         skb = NULL;
572         err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
573                              0, 0, MSG_PEEK | MSG_DONTWAIT);
574         if (err >= 0)
575                 skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
576 
577         if (skb == NULL) {
578                 if (err != -EAGAIN) {
579                         /* possibly an icmp error */
580                         dprintk("svc: recvfrom returned error %d\n", -err);
581                         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
582                 }
583                 return 0;
584         }
585         len = svc_addr_len(svc_addr(rqstp));
586         rqstp->rq_addrlen = len;
587         if (skb->tstamp.tv64 == 0) {
588                 skb->tstamp = ktime_get_real();
589                 /* Don't enable netstamp, sunrpc doesn't
590                    need that much accuracy */
591         }
592         svsk->sk_sk->sk_stamp = skb->tstamp;
593         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
594 
595         len  = skb->len - sizeof(struct udphdr);
596         rqstp->rq_arg.len = len;
597 
598         rqstp->rq_prot = IPPROTO_UDP;
599 
600         if (!svc_udp_get_dest_address(rqstp, cmh)) {
601                 net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n",
602                                      cmh->cmsg_level, cmh->cmsg_type);
603                 goto out_free;
604         }
605         rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp));
606 
607         if (skb_is_nonlinear(skb)) {
608                 /* we have to copy */
609                 local_bh_disable();
610                 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
611                         local_bh_enable();
612                         /* checksum error */
613                         goto out_free;
614                 }
615                 local_bh_enable();
616                 skb_free_datagram_locked(svsk->sk_sk, skb);
617         } else {
618                 /* we can use it in-place */
619                 rqstp->rq_arg.head[0].iov_base = skb->data +
620                         sizeof(struct udphdr);
621                 rqstp->rq_arg.head[0].iov_len = len;
622                 if (skb_checksum_complete(skb))
623                         goto out_free;
624                 rqstp->rq_xprt_ctxt = skb;
625         }
626 
627         rqstp->rq_arg.page_base = 0;
628         if (len <= rqstp->rq_arg.head[0].iov_len) {
629                 rqstp->rq_arg.head[0].iov_len = len;
630                 rqstp->rq_arg.page_len = 0;
631                 rqstp->rq_respages = rqstp->rq_pages+1;
632         } else {
633                 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
634                 rqstp->rq_respages = rqstp->rq_pages + 1 +
635                         DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
636         }
637         rqstp->rq_next_page = rqstp->rq_respages+1;
638 
639         if (serv->sv_stats)
640                 serv->sv_stats->netudpcnt++;
641 
642         return len;
643 out_free:
644         trace_kfree_skb(skb, svc_udp_recvfrom);
645         skb_free_datagram_locked(svsk->sk_sk, skb);
646         return 0;
647 }
648 
649 static int
650 svc_udp_sendto(struct svc_rqst *rqstp)
651 {
652         int             error;
653 
654         error = svc_sendto(rqstp, &rqstp->rq_res);
655         if (error == -ECONNREFUSED)
656                 /* ICMP error on earlier request. */
657                 error = svc_sendto(rqstp, &rqstp->rq_res);
658 
659         return error;
660 }
661 
662 static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
663 {
664 }
665 
666 static int svc_udp_has_wspace(struct svc_xprt *xprt)
667 {
668         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
669         struct svc_serv *serv = xprt->xpt_server;
670         unsigned long required;
671 
672         /*
673          * Set the SOCK_NOSPACE flag before checking the available
674          * sock space.
675          */
676         set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
677         required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
678         if (required*2 > sock_wspace(svsk->sk_sk))
679                 return 0;
680         clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
681         return 1;
682 }
683 
684 static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
685 {
686         BUG();
687         return NULL;
688 }
689 
690 static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
691                                        struct net *net,
692                                        struct sockaddr *sa, int salen,
693                                        int flags)
694 {
695         return svc_create_socket(serv, IPPROTO_UDP, net, sa, salen, flags);
696 }
697 
698 static struct svc_xprt_ops svc_udp_ops = {
699         .xpo_create = svc_udp_create,
700         .xpo_recvfrom = svc_udp_recvfrom,
701         .xpo_sendto = svc_udp_sendto,
702         .xpo_release_rqst = svc_release_skb,
703         .xpo_detach = svc_sock_detach,
704         .xpo_free = svc_sock_free,
705         .xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
706         .xpo_has_wspace = svc_udp_has_wspace,
707         .xpo_accept = svc_udp_accept,
708         .xpo_secure_port = svc_sock_secure_port,
709 };
710 
711 static struct svc_xprt_class svc_udp_class = {
712         .xcl_name = "udp",
713         .xcl_owner = THIS_MODULE,
714         .xcl_ops = &svc_udp_ops,
715         .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
716         .xcl_ident = XPRT_TRANSPORT_UDP,
717 };
718 
719 static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
720 {
721         int err, level, optname, one = 1;
722 
723         svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_udp_class,
724                       &svsk->sk_xprt, serv);
725         clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
726         svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
727         svsk->sk_sk->sk_write_space = svc_write_space;
728 
729         /* initialise setting must have enough space to
730          * receive and respond to one request.
731          * svc_udp_recvfrom will re-adjust if necessary
732          */
733         svc_sock_setbufsize(svsk->sk_sock,
734                             3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
735                             3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
736 
737         /* data might have come in before data_ready set up */
738         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
739         set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
740 
741         /* make sure we get destination address info */
742         switch (svsk->sk_sk->sk_family) {
743         case AF_INET:
744                 level = SOL_IP;
745                 optname = IP_PKTINFO;
746                 break;
747         case AF_INET6:
748                 level = SOL_IPV6;
749                 optname = IPV6_RECVPKTINFO;
750                 break;
751         default:
752                 BUG();
753         }
754         err = kernel_setsockopt(svsk->sk_sock, level, optname,
755                                         (char *)&one, sizeof(one));
756         dprintk("svc: kernel_setsockopt returned %d\n", err);
757 }
758 
759 /*
760  * A data_ready event on a listening socket means there's a connection
761  * pending. Do not use state_change as a substitute for it.
762  */
763 static void svc_tcp_listen_data_ready(struct sock *sk)
764 {
765         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
766         wait_queue_head_t *wq;
767 
768         dprintk("svc: socket %p TCP (listen) state change %d\n",
769                 sk, sk->sk_state);
770 
771         /*
772          * This callback may called twice when a new connection
773          * is established as a child socket inherits everything
774          * from a parent LISTEN socket.
775          * 1) data_ready method of the parent socket will be called
776          *    when one of child sockets become ESTABLISHED.
777          * 2) data_ready method of the child socket may be called
778          *    when it receives data before the socket is accepted.
779          * In case of 2, we should ignore it silently.
780          */
781         if (sk->sk_state == TCP_LISTEN) {
782                 if (svsk) {
783                         set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
784                         svc_xprt_enqueue(&svsk->sk_xprt);
785                 } else
786                         printk("svc: socket %p: no user data\n", sk);
787         }
788 
789         wq = sk_sleep(sk);
790         if (wq && waitqueue_active(wq))
791                 wake_up_interruptible_all(wq);
792 }
793 
794 /*
795  * A state change on a connected socket means it's dying or dead.
796  */
797 static void svc_tcp_state_change(struct sock *sk)
798 {
799         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
800         wait_queue_head_t *wq = sk_sleep(sk);
801 
802         dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
803                 sk, sk->sk_state, sk->sk_user_data);
804 
805         if (!svsk)
806                 printk("svc: socket %p: no user data\n", sk);
807         else {
808                 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
809                 svc_xprt_enqueue(&svsk->sk_xprt);
810         }
811         if (wq && waitqueue_active(wq))
812                 wake_up_interruptible_all(wq);
813 }
814 
815 static void svc_tcp_data_ready(struct sock *sk)
816 {
817         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
818         wait_queue_head_t *wq = sk_sleep(sk);
819 
820         dprintk("svc: socket %p TCP data ready (svsk %p)\n",
821                 sk, sk->sk_user_data);
822         if (svsk) {
823                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
824                 svc_xprt_enqueue(&svsk->sk_xprt);
825         }
826         if (wq && waitqueue_active(wq))
827                 wake_up_interruptible(wq);
828 }
829 
830 /*
831  * Accept a TCP connection
832  */
833 static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
834 {
835         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
836         struct sockaddr_storage addr;
837         struct sockaddr *sin = (struct sockaddr *) &addr;
838         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
839         struct socket   *sock = svsk->sk_sock;
840         struct socket   *newsock;
841         struct svc_sock *newsvsk;
842         int             err, slen;
843         RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
844 
845         dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
846         if (!sock)
847                 return NULL;
848 
849         clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
850         err = kernel_accept(sock, &newsock, O_NONBLOCK);
851         if (err < 0) {
852                 if (err == -ENOMEM)
853                         printk(KERN_WARNING "%s: no more sockets!\n",
854                                serv->sv_name);
855                 else if (err != -EAGAIN)
856                         net_warn_ratelimited("%s: accept failed (err %d)!\n",
857                                              serv->sv_name, -err);
858                 return NULL;
859         }
860         set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
861 
862         err = kernel_getpeername(newsock, sin, &slen);
863         if (err < 0) {
864                 net_warn_ratelimited("%s: peername failed (err %d)!\n",
865                                      serv->sv_name, -err);
866                 goto failed;            /* aborted connection or whatever */
867         }
868 
869         /* Ideally, we would want to reject connections from unauthorized
870          * hosts here, but when we get encryption, the IP of the host won't
871          * tell us anything.  For now just warn about unpriv connections.
872          */
873         if (!svc_port_is_privileged(sin)) {
874                 dprintk("%s: connect from unprivileged port: %s\n",
875                         serv->sv_name,
876                         __svc_print_addr(sin, buf, sizeof(buf)));
877         }
878         dprintk("%s: connect from %s\n", serv->sv_name,
879                 __svc_print_addr(sin, buf, sizeof(buf)));
880 
881         /* make sure that a write doesn't block forever when
882          * low on memory
883          */
884         newsock->sk->sk_sndtimeo = HZ*30;
885 
886         newsvsk = svc_setup_socket(serv, newsock,
887                                  (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY));
888         if (IS_ERR(newsvsk))
889                 goto failed;
890         svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
891         err = kernel_getsockname(newsock, sin, &slen);
892         if (unlikely(err < 0)) {
893                 dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
894                 slen = offsetof(struct sockaddr, sa_data);
895         }
896         svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
897 
898         if (sock_is_loopback(newsock->sk))
899                 set_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
900         else
901                 clear_bit(XPT_LOCAL, &newsvsk->sk_xprt.xpt_flags);
902         if (serv->sv_stats)
903                 serv->sv_stats->nettcpconn++;
904 
905         return &newsvsk->sk_xprt;
906 
907 failed:
908         sock_release(newsock);
909         return NULL;
910 }
911 
912 static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
913 {
914         unsigned int i, len, npages;
915 
916         if (svsk->sk_datalen == 0)
917                 return 0;
918         len = svsk->sk_datalen;
919         npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
920         for (i = 0; i < npages; i++) {
921                 if (rqstp->rq_pages[i] != NULL)
922                         put_page(rqstp->rq_pages[i]);
923                 BUG_ON(svsk->sk_pages[i] == NULL);
924                 rqstp->rq_pages[i] = svsk->sk_pages[i];
925                 svsk->sk_pages[i] = NULL;
926         }
927         rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
928         return len;
929 }
930 
931 static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
932 {
933         unsigned int i, len, npages;
934 
935         if (svsk->sk_datalen == 0)
936                 return;
937         len = svsk->sk_datalen;
938         npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
939         for (i = 0; i < npages; i++) {
940                 svsk->sk_pages[i] = rqstp->rq_pages[i];
941                 rqstp->rq_pages[i] = NULL;
942         }
943 }
944 
945 static void svc_tcp_clear_pages(struct svc_sock *svsk)
946 {
947         unsigned int i, len, npages;
948 
949         if (svsk->sk_datalen == 0)
950                 goto out;
951         len = svsk->sk_datalen;
952         npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
953         for (i = 0; i < npages; i++) {
954                 if (svsk->sk_pages[i] == NULL) {
955                         WARN_ON_ONCE(1);
956                         continue;
957                 }
958                 put_page(svsk->sk_pages[i]);
959                 svsk->sk_pages[i] = NULL;
960         }
961 out:
962         svsk->sk_tcplen = 0;
963         svsk->sk_datalen = 0;
964 }
965 
966 /*
967  * Receive fragment record header.
968  * If we haven't gotten the record length yet, get the next four bytes.
969  */
970 static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
971 {
972         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
973         unsigned int want;
974         int len;
975 
976         if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
977                 struct kvec     iov;
978 
979                 want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
980                 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
981                 iov.iov_len  = want;
982                 if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
983                         goto error;
984                 svsk->sk_tcplen += len;
985 
986                 if (len < want) {
987                         dprintk("svc: short recvfrom while reading record "
988                                 "length (%d of %d)\n", len, want);
989                         return -EAGAIN;
990                 }
991 
992                 dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk));
993                 if (svc_sock_reclen(svsk) + svsk->sk_datalen >
994                                                         serv->sv_max_mesg) {
995                         net_notice_ratelimited("RPC: fragment too large: %d\n",
996                                         svc_sock_reclen(svsk));
997                         goto err_delete;
998                 }
999         }
1000 
1001         return svc_sock_reclen(svsk);
1002 error:
1003         dprintk("RPC: TCP recv_record got %d\n", len);
1004         return len;
1005 err_delete:
1006         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1007         return -EAGAIN;
1008 }
1009 
1010 static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
1011 {
1012         struct rpc_xprt *bc_xprt = svsk->sk_xprt.xpt_bc_xprt;
1013         struct rpc_rqst *req = NULL;
1014         struct kvec *src, *dst;
1015         __be32 *p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1016         __be32 xid;
1017         __be32 calldir;
1018 
1019         xid = *p++;
1020         calldir = *p;
1021 
1022         if (!bc_xprt)
1023                 return -EAGAIN;
1024         spin_lock_bh(&bc_xprt->transport_lock);
1025         req = xprt_lookup_rqst(bc_xprt, xid);
1026         if (!req)
1027                 goto unlock_notfound;
1028 
1029         memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
1030         /*
1031          * XXX!: cheating for now!  Only copying HEAD.
1032          * But we know this is good enough for now (in fact, for any
1033          * callback reply in the forseeable future).
1034          */
1035         dst = &req->rq_private_buf.head[0];
1036         src = &rqstp->rq_arg.head[0];
1037         if (dst->iov_len < src->iov_len)
1038                 goto unlock_eagain; /* whatever; just giving up. */
1039         memcpy(dst->iov_base, src->iov_base, src->iov_len);
1040         xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
1041         rqstp->rq_arg.len = 0;
1042         spin_unlock_bh(&bc_xprt->transport_lock);
1043         return 0;
1044 unlock_notfound:
1045         printk(KERN_NOTICE
1046                 "%s: Got unrecognized reply: "
1047                 "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
1048                 __func__, ntohl(calldir),
1049                 bc_xprt, ntohl(xid));
1050 unlock_eagain:
1051         spin_unlock_bh(&bc_xprt->transport_lock);
1052         return -EAGAIN;
1053 }
1054 
1055 static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
1056 {
1057         int i = 0;
1058         int t = 0;
1059 
1060         while (t < len) {
1061                 vec[i].iov_base = page_address(pages[i]);
1062                 vec[i].iov_len = PAGE_SIZE;
1063                 i++;
1064                 t += PAGE_SIZE;
1065         }
1066         return i;
1067 }
1068 
1069 static void svc_tcp_fragment_received(struct svc_sock *svsk)
1070 {
1071         /* If we have more data, signal svc_xprt_enqueue() to try again */
1072         dprintk("svc: TCP %s record (%d bytes)\n",
1073                 svc_sock_final_rec(svsk) ? "final" : "nonfinal",
1074                 svc_sock_reclen(svsk));
1075         svsk->sk_tcplen = 0;
1076         svsk->sk_reclen = 0;
1077 }
1078 
1079 /*
1080  * Receive data from a TCP socket.
1081  */
1082 static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
1083 {
1084         struct svc_sock *svsk =
1085                 container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
1086         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1087         int             len;
1088         struct kvec *vec;
1089         unsigned int want, base;
1090         __be32 *p;
1091         __be32 calldir;
1092         int pnum;
1093 
1094         dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1095                 svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1096                 test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1097                 test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1098 
1099         len = svc_tcp_recv_record(svsk, rqstp);
1100         if (len < 0)
1101                 goto error;
1102 
1103         base = svc_tcp_restore_pages(svsk, rqstp);
1104         want = svc_sock_reclen(svsk) - (svsk->sk_tcplen - sizeof(rpc_fraghdr));
1105 
1106         vec = rqstp->rq_vec;
1107 
1108         pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
1109                                                 svsk->sk_datalen + want);
1110 
1111         rqstp->rq_respages = &rqstp->rq_pages[pnum];
1112         rqstp->rq_next_page = rqstp->rq_respages + 1;
1113 
1114         /* Now receive data */
1115         len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
1116         if (len >= 0) {
1117                 svsk->sk_tcplen += len;
1118                 svsk->sk_datalen += len;
1119         }
1120         if (len != want || !svc_sock_final_rec(svsk)) {
1121                 svc_tcp_save_pages(svsk, rqstp);
1122                 if (len < 0 && len != -EAGAIN)
1123                         goto err_delete;
1124                 if (len == want)
1125                         svc_tcp_fragment_received(svsk);
1126                 else
1127                         dprintk("svc: incomplete TCP record (%d of %d)\n",
1128                                 (int)(svsk->sk_tcplen - sizeof(rpc_fraghdr)),
1129                                 svc_sock_reclen(svsk));
1130                 goto err_noclose;
1131         }
1132 
1133         if (svsk->sk_datalen < 8) {
1134                 svsk->sk_datalen = 0;
1135                 goto err_delete; /* client is nuts. */
1136         }
1137 
1138         rqstp->rq_arg.len = svsk->sk_datalen;
1139         rqstp->rq_arg.page_base = 0;
1140         if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
1141                 rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
1142                 rqstp->rq_arg.page_len = 0;
1143         } else
1144                 rqstp->rq_arg.page_len = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
1145 
1146         rqstp->rq_xprt_ctxt   = NULL;
1147         rqstp->rq_prot        = IPPROTO_TCP;
1148         if (test_bit(XPT_LOCAL, &svsk->sk_xprt.xpt_flags))
1149                 set_bit(RQ_LOCAL, &rqstp->rq_flags);
1150         else
1151                 clear_bit(RQ_LOCAL, &rqstp->rq_flags);
1152 
1153         p = (__be32 *)rqstp->rq_arg.head[0].iov_base;
1154         calldir = p[1];
1155         if (calldir)
1156                 len = receive_cb_reply(svsk, rqstp);
1157 
1158         /* Reset TCP read info */
1159         svsk->sk_datalen = 0;
1160         svc_tcp_fragment_received(svsk);
1161 
1162         if (len < 0)
1163                 goto error;
1164 
1165         svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
1166         if (serv->sv_stats)
1167                 serv->sv_stats->nettcpcnt++;
1168 
1169         return rqstp->rq_arg.len;
1170 
1171 error:
1172         if (len != -EAGAIN)
1173                 goto err_delete;
1174         dprintk("RPC: TCP recvfrom got EAGAIN\n");
1175         return 0;
1176 err_delete:
1177         printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1178                svsk->sk_xprt.xpt_server->sv_name, -len);
1179         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1180 err_noclose:
1181         return 0;       /* record not complete */
1182 }
1183 
1184 /*
1185  * Send out data on TCP socket.
1186  */
1187 static int svc_tcp_sendto(struct svc_rqst *rqstp)
1188 {
1189         struct xdr_buf  *xbufp = &rqstp->rq_res;
1190         int sent;
1191         __be32 reclen;
1192 
1193         /* Set up the first element of the reply kvec.
1194          * Any other kvecs that may be in use have been taken
1195          * care of by the server implementation itself.
1196          */
1197         reclen = htonl(0x80000000|((xbufp->len ) - 4));
1198         memcpy(xbufp->head[0].iov_base, &reclen, 4);
1199 
1200         sent = svc_sendto(rqstp, &rqstp->rq_res);
1201         if (sent != xbufp->len) {
1202                 printk(KERN_NOTICE
1203                        "rpc-srv/tcp: %s: %s %d when sending %d bytes "
1204                        "- shutting down socket\n",
1205                        rqstp->rq_xprt->xpt_server->sv_name,
1206                        (sent<0)?"got error":"sent only",
1207                        sent, xbufp->len);
1208                 set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
1209                 svc_xprt_enqueue(rqstp->rq_xprt);
1210                 sent = -EAGAIN;
1211         }
1212         return sent;
1213 }
1214 
1215 /*
1216  * Setup response header. TCP has a 4B record length field.
1217  */
1218 static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1219 {
1220         struct kvec *resv = &rqstp->rq_res.head[0];
1221 
1222         /* tcp needs a space for the record length... */
1223         svc_putnl(resv, 0);
1224 }
1225 
1226 static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1227                                        struct net *net,
1228                                        struct sockaddr *sa, int salen,
1229                                        int flags)
1230 {
1231         return svc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1232 }
1233 
1234 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1235 static struct svc_xprt *svc_bc_create_socket(struct svc_serv *, int,
1236                                              struct net *, struct sockaddr *,
1237                                              int, int);
1238 static void svc_bc_sock_free(struct svc_xprt *xprt);
1239 
1240 static struct svc_xprt *svc_bc_tcp_create(struct svc_serv *serv,
1241                                        struct net *net,
1242                                        struct sockaddr *sa, int salen,
1243                                        int flags)
1244 {
1245         return svc_bc_create_socket(serv, IPPROTO_TCP, net, sa, salen, flags);
1246 }
1247 
1248 static void svc_bc_tcp_sock_detach(struct svc_xprt *xprt)
1249 {
1250 }
1251 
1252 static struct svc_xprt_ops svc_tcp_bc_ops = {
1253         .xpo_create = svc_bc_tcp_create,
1254         .xpo_detach = svc_bc_tcp_sock_detach,
1255         .xpo_free = svc_bc_sock_free,
1256         .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1257         .xpo_secure_port = svc_sock_secure_port,
1258 };
1259 
1260 static struct svc_xprt_class svc_tcp_bc_class = {
1261         .xcl_name = "tcp-bc",
1262         .xcl_owner = THIS_MODULE,
1263         .xcl_ops = &svc_tcp_bc_ops,
1264         .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1265 };
1266 
1267 static void svc_init_bc_xprt_sock(void)
1268 {
1269         svc_reg_xprt_class(&svc_tcp_bc_class);
1270 }
1271 
1272 static void svc_cleanup_bc_xprt_sock(void)
1273 {
1274         svc_unreg_xprt_class(&svc_tcp_bc_class);
1275 }
1276 #else /* CONFIG_SUNRPC_BACKCHANNEL */
1277 static void svc_init_bc_xprt_sock(void)
1278 {
1279 }
1280 
1281 static void svc_cleanup_bc_xprt_sock(void)
1282 {
1283 }
1284 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1285 
1286 static struct svc_xprt_ops svc_tcp_ops = {
1287         .xpo_create = svc_tcp_create,
1288         .xpo_recvfrom = svc_tcp_recvfrom,
1289         .xpo_sendto = svc_tcp_sendto,
1290         .xpo_release_rqst = svc_release_skb,
1291         .xpo_detach = svc_tcp_sock_detach,
1292         .xpo_free = svc_sock_free,
1293         .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1294         .xpo_has_wspace = svc_tcp_has_wspace,
1295         .xpo_accept = svc_tcp_accept,
1296         .xpo_secure_port = svc_sock_secure_port,
1297         .xpo_adjust_wspace = svc_tcp_adjust_wspace,
1298 };
1299 
1300 static struct svc_xprt_class svc_tcp_class = {
1301         .xcl_name = "tcp",
1302         .xcl_owner = THIS_MODULE,
1303         .xcl_ops = &svc_tcp_ops,
1304         .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1305         .xcl_ident = XPRT_TRANSPORT_TCP,
1306 };
1307 
1308 void svc_init_xprt_sock(void)
1309 {
1310         svc_reg_xprt_class(&svc_tcp_class);
1311         svc_reg_xprt_class(&svc_udp_class);
1312         svc_init_bc_xprt_sock();
1313 }
1314 
1315 void svc_cleanup_xprt_sock(void)
1316 {
1317         svc_unreg_xprt_class(&svc_tcp_class);
1318         svc_unreg_xprt_class(&svc_udp_class);
1319         svc_cleanup_bc_xprt_sock();
1320 }
1321 
1322 static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1323 {
1324         struct sock     *sk = svsk->sk_sk;
1325 
1326         svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
1327                       &svsk->sk_xprt, serv);
1328         set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1329         if (sk->sk_state == TCP_LISTEN) {
1330                 dprintk("setting up TCP socket for listening\n");
1331                 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1332                 sk->sk_data_ready = svc_tcp_listen_data_ready;
1333                 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1334         } else {
1335                 dprintk("setting up TCP socket for reading\n");
1336                 sk->sk_state_change = svc_tcp_state_change;
1337                 sk->sk_data_ready = svc_tcp_data_ready;
1338                 sk->sk_write_space = svc_tcp_write_space;
1339 
1340                 svsk->sk_reclen = 0;
1341                 svsk->sk_tcplen = 0;
1342                 svsk->sk_datalen = 0;
1343                 memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
1344 
1345                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1346 
1347                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1348                 if (sk->sk_state != TCP_ESTABLISHED)
1349                         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1350         }
1351 }
1352 
1353 void svc_sock_update_bufs(struct svc_serv *serv)
1354 {
1355         /*
1356          * The number of server threads has changed. Update
1357          * rcvbuf and sndbuf accordingly on all sockets
1358          */
1359         struct svc_sock *svsk;
1360 
1361         spin_lock_bh(&serv->sv_lock);
1362         list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list)
1363                 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1364         spin_unlock_bh(&serv->sv_lock);
1365 }
1366 EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1367 
1368 /*
1369  * Initialize socket for RPC use and create svc_sock struct
1370  * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1371  */
1372 static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1373                                                 struct socket *sock,
1374                                                 int flags)
1375 {
1376         struct svc_sock *svsk;
1377         struct sock     *inet;
1378         int             pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1379         int             err = 0;
1380 
1381         dprintk("svc: svc_setup_socket %p\n", sock);
1382         svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1383         if (!svsk)
1384                 return ERR_PTR(-ENOMEM);
1385 
1386         inet = sock->sk;
1387 
1388         /* Register socket with portmapper */
1389         if (pmap_register)
1390                 err = svc_register(serv, sock_net(sock->sk), inet->sk_family,
1391                                      inet->sk_protocol,
1392                                      ntohs(inet_sk(inet)->inet_sport));
1393 
1394         if (err < 0) {
1395                 kfree(svsk);
1396                 return ERR_PTR(err);
1397         }
1398 
1399         inet->sk_user_data = svsk;
1400         svsk->sk_sock = sock;
1401         svsk->sk_sk = inet;
1402         svsk->sk_ostate = inet->sk_state_change;
1403         svsk->sk_odata = inet->sk_data_ready;
1404         svsk->sk_owspace = inet->sk_write_space;
1405 
1406         /* Initialize the socket */
1407         if (sock->type == SOCK_DGRAM)
1408                 svc_udp_init(svsk, serv);
1409         else {
1410                 /* initialise setting must have enough space to
1411                  * receive and respond to one request.
1412                  */
1413                 svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
1414                                         4 * serv->sv_max_mesg);
1415                 svc_tcp_init(svsk, serv);
1416         }
1417 
1418         dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1419                                 svsk, svsk->sk_sk);
1420 
1421         return svsk;
1422 }
1423 
1424 bool svc_alien_sock(struct net *net, int fd)
1425 {
1426         int err;
1427         struct socket *sock = sockfd_lookup(fd, &err);
1428         bool ret = false;
1429 
1430         if (!sock)
1431                 goto out;
1432         if (sock_net(sock->sk) != net)
1433                 ret = true;
1434         sockfd_put(sock);
1435 out:
1436         return ret;
1437 }
1438 EXPORT_SYMBOL_GPL(svc_alien_sock);
1439 
1440 /**
1441  * svc_addsock - add a listener socket to an RPC service
1442  * @serv: pointer to RPC service to which to add a new listener
1443  * @fd: file descriptor of the new listener
1444  * @name_return: pointer to buffer to fill in with name of listener
1445  * @len: size of the buffer
1446  *
1447  * Fills in socket name and returns positive length of name if successful.
1448  * Name is terminated with '\n'.  On error, returns a negative errno
1449  * value.
1450  */
1451 int svc_addsock(struct svc_serv *serv, const int fd, char *name_return,
1452                 const size_t len)
1453 {
1454         int err = 0;
1455         struct socket *so = sockfd_lookup(fd, &err);
1456         struct svc_sock *svsk = NULL;
1457         struct sockaddr_storage addr;
1458         struct sockaddr *sin = (struct sockaddr *)&addr;
1459         int salen;
1460 
1461         if (!so)
1462                 return err;
1463         err = -EAFNOSUPPORT;
1464         if ((so->sk->sk_family != PF_INET) && (so->sk->sk_family != PF_INET6))
1465                 goto out;
1466         err =  -EPROTONOSUPPORT;
1467         if (so->sk->sk_protocol != IPPROTO_TCP &&
1468             so->sk->sk_protocol != IPPROTO_UDP)
1469                 goto out;
1470         err = -EISCONN;
1471         if (so->state > SS_UNCONNECTED)
1472                 goto out;
1473         err = -ENOENT;
1474         if (!try_module_get(THIS_MODULE))
1475                 goto out;
1476         svsk = svc_setup_socket(serv, so, SVC_SOCK_DEFAULTS);
1477         if (IS_ERR(svsk)) {
1478                 module_put(THIS_MODULE);
1479                 err = PTR_ERR(svsk);
1480                 goto out;
1481         }
1482         if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
1483                 svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1484         svc_add_new_perm_xprt(serv, &svsk->sk_xprt);
1485         return svc_one_sock_name(svsk, name_return, len);
1486 out:
1487         sockfd_put(so);
1488         return err;
1489 }
1490 EXPORT_SYMBOL_GPL(svc_addsock);
1491 
1492 /*
1493  * Create socket for RPC service.
1494  */
1495 static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1496                                           int protocol,
1497                                           struct net *net,
1498                                           struct sockaddr *sin, int len,
1499                                           int flags)
1500 {
1501         struct svc_sock *svsk;
1502         struct socket   *sock;
1503         int             error;
1504         int             type;
1505         struct sockaddr_storage addr;
1506         struct sockaddr *newsin = (struct sockaddr *)&addr;
1507         int             newlen;
1508         int             family;
1509         int             val;
1510         RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1511 
1512         dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1513                         serv->sv_program->pg_name, protocol,
1514                         __svc_print_addr(sin, buf, sizeof(buf)));
1515 
1516         if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1517                 printk(KERN_WARNING "svc: only UDP and TCP "
1518                                 "sockets supported\n");
1519                 return ERR_PTR(-EINVAL);
1520         }
1521 
1522         type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1523         switch (sin->sa_family) {
1524         case AF_INET6:
1525                 family = PF_INET6;
1526                 break;
1527         case AF_INET:
1528                 family = PF_INET;
1529                 break;
1530         default:
1531                 return ERR_PTR(-EINVAL);
1532         }
1533 
1534         error = __sock_create(net, family, type, protocol, &sock, 1);
1535         if (error < 0)
1536                 return ERR_PTR(error);
1537 
1538         svc_reclassify_socket(sock);
1539 
1540         /*
1541          * If this is an PF_INET6 listener, we want to avoid
1542          * getting requests from IPv4 remotes.  Those should
1543          * be shunted to a PF_INET listener via rpcbind.
1544          */
1545         val = 1;
1546         if (family == PF_INET6)
1547                 kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1548                                         (char *)&val, sizeof(val));
1549 
1550         if (type == SOCK_STREAM)
1551                 sock->sk->sk_reuse = SK_CAN_REUSE; /* allow address reuse */
1552         error = kernel_bind(sock, sin, len);
1553         if (error < 0)
1554                 goto bummer;
1555 
1556         newlen = len;
1557         error = kernel_getsockname(sock, newsin, &newlen);
1558         if (error < 0)
1559                 goto bummer;
1560 
1561         if (protocol == IPPROTO_TCP) {
1562                 if ((error = kernel_listen(sock, 64)) < 0)
1563                         goto bummer;
1564         }
1565 
1566         svsk = svc_setup_socket(serv, sock, flags);
1567         if (IS_ERR(svsk)) {
1568                 error = PTR_ERR(svsk);
1569                 goto bummer;
1570         }
1571         svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1572         return (struct svc_xprt *)svsk;
1573 bummer:
1574         dprintk("svc: svc_create_socket error = %d\n", -error);
1575         sock_release(sock);
1576         return ERR_PTR(error);
1577 }
1578 
1579 /*
1580  * Detach the svc_sock from the socket so that no
1581  * more callbacks occur.
1582  */
1583 static void svc_sock_detach(struct svc_xprt *xprt)
1584 {
1585         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1586         struct sock *sk = svsk->sk_sk;
1587         wait_queue_head_t *wq;
1588 
1589         dprintk("svc: svc_sock_detach(%p)\n", svsk);
1590 
1591         /* put back the old socket callbacks */
1592         sk->sk_state_change = svsk->sk_ostate;
1593         sk->sk_data_ready = svsk->sk_odata;
1594         sk->sk_write_space = svsk->sk_owspace;
1595 
1596         wq = sk_sleep(sk);
1597         if (wq && waitqueue_active(wq))
1598                 wake_up_interruptible(wq);
1599 }
1600 
1601 /*
1602  * Disconnect the socket, and reset the callbacks
1603  */
1604 static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1605 {
1606         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1607 
1608         dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1609 
1610         svc_sock_detach(xprt);
1611 
1612         if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
1613                 svc_tcp_clear_pages(svsk);
1614                 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1615         }
1616 }
1617 
1618 /*
1619  * Free the svc_sock's socket resources and the svc_sock itself.
1620  */
1621 static void svc_sock_free(struct svc_xprt *xprt)
1622 {
1623         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1624         dprintk("svc: svc_sock_free(%p)\n", svsk);
1625 
1626         if (svsk->sk_sock->file)
1627                 sockfd_put(svsk->sk_sock);
1628         else
1629                 sock_release(svsk->sk_sock);
1630         kfree(svsk);
1631 }
1632 
1633 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1634 /*
1635  * Create a back channel svc_xprt which shares the fore channel socket.
1636  */
1637 static struct svc_xprt *svc_bc_create_socket(struct svc_serv *serv,
1638                                              int protocol,
1639                                              struct net *net,
1640                                              struct sockaddr *sin, int len,
1641                                              int flags)
1642 {
1643         struct svc_sock *svsk;
1644         struct svc_xprt *xprt;
1645 
1646         if (protocol != IPPROTO_TCP) {
1647                 printk(KERN_WARNING "svc: only TCP sockets"
1648                         " supported on shared back channel\n");
1649                 return ERR_PTR(-EINVAL);
1650         }
1651 
1652         svsk = kzalloc(sizeof(*svsk), GFP_KERNEL);
1653         if (!svsk)
1654                 return ERR_PTR(-ENOMEM);
1655 
1656         xprt = &svsk->sk_xprt;
1657         svc_xprt_init(net, &svc_tcp_bc_class, xprt, serv);
1658 
1659         serv->sv_bc_xprt = xprt;
1660 
1661         return xprt;
1662 }
1663 
1664 /*
1665  * Free a back channel svc_sock.
1666  */
1667 static void svc_bc_sock_free(struct svc_xprt *xprt)
1668 {
1669         if (xprt)
1670                 kfree(container_of(xprt, struct svc_sock, sk_xprt));
1671 }
1672 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1673 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp