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