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_sock_enqueue procedure... 9 * 10 * TCP support is largely untested and may be a little slow. The problem 11 * is that we currently do two separate recvfrom's, one for the 4-byte 12 * record length, and the second for the actual record. This could possibly 13 * be improved by always reading a minimum size of around 100 bytes and 14 * tucking any superfluous bytes away in a temporary store. Still, that 15 * leaves write requests out in the rain. An alternative may be to peek at 16 * the first skb in the queue, and if it matches the next TCP sequence 17 * number, to extract the record marker. Yuck. 18 * 19 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 20 */ 21 22 #include <linux/kernel.h> 23 #include <linux/sched.h> 24 #include <linux/errno.h> 25 #include <linux/fcntl.h> 26 #include <linux/net.h> 27 #include <linux/in.h> 28 #include <linux/inet.h> 29 #include <linux/udp.h> 30 #include <linux/tcp.h> 31 #include <linux/unistd.h> 32 #include <linux/slab.h> 33 #include <linux/netdevice.h> 34 #include <linux/skbuff.h> 35 #include <linux/file.h> 36 #include <linux/freezer.h> 37 #include <net/sock.h> 38 #include <net/checksum.h> 39 #include <net/ip.h> 40 #include <net/ipv6.h> 41 #include <net/tcp_states.h> 42 #include <asm/uaccess.h> 43 #include <asm/ioctls.h> 44 45 #include <linux/sunrpc/types.h> 46 #include <linux/sunrpc/clnt.h> 47 #include <linux/sunrpc/xdr.h> 48 #include <linux/sunrpc/svcsock.h> 49 #include <linux/sunrpc/stats.h> 50 51 /* SMP locking strategy: 52 * 53 * svc_pool->sp_lock protects most of the fields of that pool. 54 * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt. 55 * when both need to be taken (rare), svc_serv->sv_lock is first. 56 * BKL protects svc_serv->sv_nrthread. 57 * svc_sock->sk_lock protects the svc_sock->sk_deferred list 58 * and the ->sk_info_authunix cache. 59 * svc_sock->sk_flags.SK_BUSY prevents a svc_sock being enqueued multiply. 60 * 61 * Some flags can be set to certain values at any time 62 * providing that certain rules are followed: 63 * 64 * SK_CONN, SK_DATA, can be set or cleared at any time. 65 * after a set, svc_sock_enqueue must be called. 66 * after a clear, the socket must be read/accepted 67 * if this succeeds, it must be set again. 68 * SK_CLOSE can set at any time. It is never cleared. 69 * sk_inuse contains a bias of '1' until SK_DEAD is set. 70 * so when sk_inuse hits zero, we know the socket is dead 71 * and no-one is using it. 72 * SK_DEAD can only be set while SK_BUSY is held which ensures 73 * no other thread will be using the socket or will try to 74 * set SK_DEAD. 75 * 76 */ 77 78 #define RPCDBG_FACILITY RPCDBG_SVCSOCK 79 80 81 static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, 82 int *errp, int flags); 83 static void svc_delete_socket(struct svc_sock *svsk); 84 static void svc_udp_data_ready(struct sock *, int); 85 static int svc_udp_recvfrom(struct svc_rqst *); 86 static int svc_udp_sendto(struct svc_rqst *); 87 static void svc_close_socket(struct svc_sock *svsk); 88 89 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk); 90 static int svc_deferred_recv(struct svc_rqst *rqstp); 91 static struct cache_deferred_req *svc_defer(struct cache_req *req); 92 93 /* apparently the "standard" is that clients close 94 * idle connections after 5 minutes, servers after 95 * 6 minutes 96 * http://www.connectathon.org/talks96/nfstcp.pdf 97 */ 98 static int svc_conn_age_period = 6*60; 99 100 #ifdef CONFIG_DEBUG_LOCK_ALLOC 101 static struct lock_class_key svc_key[2]; 102 static struct lock_class_key svc_slock_key[2]; 103 104 static inline void svc_reclassify_socket(struct socket *sock) 105 { 106 struct sock *sk = sock->sk; 107 BUG_ON(sk->sk_lock.owner != NULL); 108 switch (sk->sk_family) { 109 case AF_INET: 110 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD", 111 &svc_slock_key[0], "sk_lock-AF_INET-NFSD", &svc_key[0]); 112 break; 113 114 case AF_INET6: 115 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD", 116 &svc_slock_key[1], "sk_lock-AF_INET6-NFSD", &svc_key[1]); 117 break; 118 119 default: 120 BUG(); 121 } 122 } 123 #else 124 static inline void svc_reclassify_socket(struct socket *sock) 125 { 126 } 127 #endif 128 129 static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len) 130 { 131 switch (addr->sa_family) { 132 case AF_INET: 133 snprintf(buf, len, "%u.%u.%u.%u, port=%u", 134 NIPQUAD(((struct sockaddr_in *) addr)->sin_addr), 135 ntohs(((struct sockaddr_in *) addr)->sin_port)); 136 break; 137 138 case AF_INET6: 139 snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u", 140 NIP6(((struct sockaddr_in6 *) addr)->sin6_addr), 141 ntohs(((struct sockaddr_in6 *) addr)->sin6_port)); 142 break; 143 144 default: 145 snprintf(buf, len, "unknown address type: %d", addr->sa_family); 146 break; 147 } 148 return buf; 149 } 150 151 /** 152 * svc_print_addr - Format rq_addr field for printing 153 * @rqstp: svc_rqst struct containing address to print 154 * @buf: target buffer for formatted address 155 * @len: length of target buffer 156 * 157 */ 158 char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len) 159 { 160 return __svc_print_addr(svc_addr(rqstp), buf, len); 161 } 162 EXPORT_SYMBOL_GPL(svc_print_addr); 163 164 /* 165 * Queue up an idle server thread. Must have pool->sp_lock held. 166 * Note: this is really a stack rather than a queue, so that we only 167 * use as many different threads as we need, and the rest don't pollute 168 * the cache. 169 */ 170 static inline void 171 svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp) 172 { 173 list_add(&rqstp->rq_list, &pool->sp_threads); 174 } 175 176 /* 177 * Dequeue an nfsd thread. Must have pool->sp_lock held. 178 */ 179 static inline void 180 svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp) 181 { 182 list_del(&rqstp->rq_list); 183 } 184 185 /* 186 * Release an skbuff after use 187 */ 188 static inline void 189 svc_release_skb(struct svc_rqst *rqstp) 190 { 191 struct sk_buff *skb = rqstp->rq_skbuff; 192 struct svc_deferred_req *dr = rqstp->rq_deferred; 193 194 if (skb) { 195 rqstp->rq_skbuff = NULL; 196 197 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb); 198 skb_free_datagram(rqstp->rq_sock->sk_sk, skb); 199 } 200 if (dr) { 201 rqstp->rq_deferred = NULL; 202 kfree(dr); 203 } 204 } 205 206 /* 207 * Any space to write? 208 */ 209 static inline unsigned long 210 svc_sock_wspace(struct svc_sock *svsk) 211 { 212 int wspace; 213 214 if (svsk->sk_sock->type == SOCK_STREAM) 215 wspace = sk_stream_wspace(svsk->sk_sk); 216 else 217 wspace = sock_wspace(svsk->sk_sk); 218 219 return wspace; 220 } 221 222 /* 223 * Queue up a socket with data pending. If there are idle nfsd 224 * processes, wake 'em up. 225 * 226 */ 227 static void 228 svc_sock_enqueue(struct svc_sock *svsk) 229 { 230 struct svc_serv *serv = svsk->sk_server; 231 struct svc_pool *pool; 232 struct svc_rqst *rqstp; 233 int cpu; 234 235 if (!(svsk->sk_flags & 236 ( (1<<SK_CONN)|(1<<SK_DATA)|(1<<SK_CLOSE)|(1<<SK_DEFERRED)) )) 237 return; 238 if (test_bit(SK_DEAD, &svsk->sk_flags)) 239 return; 240 241 cpu = get_cpu(); 242 pool = svc_pool_for_cpu(svsk->sk_server, cpu); 243 put_cpu(); 244 245 spin_lock_bh(&pool->sp_lock); 246 247 if (!list_empty(&pool->sp_threads) && 248 !list_empty(&pool->sp_sockets)) 249 printk(KERN_ERR 250 "svc_sock_enqueue: threads and sockets both waiting??\n"); 251 252 if (test_bit(SK_DEAD, &svsk->sk_flags)) { 253 /* Don't enqueue dead sockets */ 254 dprintk("svc: socket %p is dead, not enqueued\n", svsk->sk_sk); 255 goto out_unlock; 256 } 257 258 /* Mark socket as busy. It will remain in this state until the 259 * server has processed all pending data and put the socket back 260 * on the idle list. We update SK_BUSY atomically because 261 * it also guards against trying to enqueue the svc_sock twice. 262 */ 263 if (test_and_set_bit(SK_BUSY, &svsk->sk_flags)) { 264 /* Don't enqueue socket while already enqueued */ 265 dprintk("svc: socket %p busy, not enqueued\n", svsk->sk_sk); 266 goto out_unlock; 267 } 268 BUG_ON(svsk->sk_pool != NULL); 269 svsk->sk_pool = pool; 270 271 set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 272 if (((atomic_read(&svsk->sk_reserved) + serv->sv_max_mesg)*2 273 > svc_sock_wspace(svsk)) 274 && !test_bit(SK_CLOSE, &svsk->sk_flags) 275 && !test_bit(SK_CONN, &svsk->sk_flags)) { 276 /* Don't enqueue while not enough space for reply */ 277 dprintk("svc: socket %p no space, %d*2 > %ld, not enqueued\n", 278 svsk->sk_sk, atomic_read(&svsk->sk_reserved)+serv->sv_max_mesg, 279 svc_sock_wspace(svsk)); 280 svsk->sk_pool = NULL; 281 clear_bit(SK_BUSY, &svsk->sk_flags); 282 goto out_unlock; 283 } 284 clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); 285 286 287 if (!list_empty(&pool->sp_threads)) { 288 rqstp = list_entry(pool->sp_threads.next, 289 struct svc_rqst, 290 rq_list); 291 dprintk("svc: socket %p served by daemon %p\n", 292 svsk->sk_sk, rqstp); 293 svc_thread_dequeue(pool, rqstp); 294 if (rqstp->rq_sock) 295 printk(KERN_ERR 296 "svc_sock_enqueue: server %p, rq_sock=%p!\n", 297 rqstp, rqstp->rq_sock); 298 rqstp->rq_sock = svsk; 299 atomic_inc(&svsk->sk_inuse); 300 rqstp->rq_reserved = serv->sv_max_mesg; 301 atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); 302 BUG_ON(svsk->sk_pool != pool); 303 wake_up(&rqstp->rq_wait); 304 } else { 305 dprintk("svc: socket %p put into queue\n", svsk->sk_sk); 306 list_add_tail(&svsk->sk_ready, &pool->sp_sockets); 307 BUG_ON(svsk->sk_pool != pool); 308 } 309 310 out_unlock: 311 spin_unlock_bh(&pool->sp_lock); 312 } 313 314 /* 315 * Dequeue the first socket. Must be called with the pool->sp_lock held. 316 */ 317 static inline struct svc_sock * 318 svc_sock_dequeue(struct svc_pool *pool) 319 { 320 struct svc_sock *svsk; 321 322 if (list_empty(&pool->sp_sockets)) 323 return NULL; 324 325 svsk = list_entry(pool->sp_sockets.next, 326 struct svc_sock, sk_ready); 327 list_del_init(&svsk->sk_ready); 328 329 dprintk("svc: socket %p dequeued, inuse=%d\n", 330 svsk->sk_sk, atomic_read(&svsk->sk_inuse)); 331 332 return svsk; 333 } 334 335 /* 336 * Having read something from a socket, check whether it 337 * needs to be re-enqueued. 338 * Note: SK_DATA only gets cleared when a read-attempt finds 339 * no (or insufficient) data. 340 */ 341 static inline void 342 svc_sock_received(struct svc_sock *svsk) 343 { 344 svsk->sk_pool = NULL; 345 clear_bit(SK_BUSY, &svsk->sk_flags); 346 svc_sock_enqueue(svsk); 347 } 348 349 350 /** 351 * svc_reserve - change the space reserved for the reply to a request. 352 * @rqstp: The request in question 353 * @space: new max space to reserve 354 * 355 * Each request reserves some space on the output queue of the socket 356 * to make sure the reply fits. This function reduces that reserved 357 * space to be the amount of space used already, plus @space. 358 * 359 */ 360 void svc_reserve(struct svc_rqst *rqstp, int space) 361 { 362 space += rqstp->rq_res.head[0].iov_len; 363 364 if (space < rqstp->rq_reserved) { 365 struct svc_sock *svsk = rqstp->rq_sock; 366 atomic_sub((rqstp->rq_reserved - space), &svsk->sk_reserved); 367 rqstp->rq_reserved = space; 368 369 svc_sock_enqueue(svsk); 370 } 371 } 372 373 /* 374 * Release a socket after use. 375 */ 376 static inline void 377 svc_sock_put(struct svc_sock *svsk) 378 { 379 if (atomic_dec_and_test(&svsk->sk_inuse)) { 380 BUG_ON(! test_bit(SK_DEAD, &svsk->sk_flags)); 381 382 dprintk("svc: releasing dead socket\n"); 383 if (svsk->sk_sock->file) 384 sockfd_put(svsk->sk_sock); 385 else 386 sock_release(svsk->sk_sock); 387 if (svsk->sk_info_authunix != NULL) 388 svcauth_unix_info_release(svsk->sk_info_authunix); 389 kfree(svsk); 390 } 391 } 392 393 static void 394 svc_sock_release(struct svc_rqst *rqstp) 395 { 396 struct svc_sock *svsk = rqstp->rq_sock; 397 398 svc_release_skb(rqstp); 399 400 svc_free_res_pages(rqstp); 401 rqstp->rq_res.page_len = 0; 402 rqstp->rq_res.page_base = 0; 403 404 405 /* Reset response buffer and release 406 * the reservation. 407 * But first, check that enough space was reserved 408 * for the reply, otherwise we have a bug! 409 */ 410 if ((rqstp->rq_res.len) > rqstp->rq_reserved) 411 printk(KERN_ERR "RPC request reserved %d but used %d\n", 412 rqstp->rq_reserved, 413 rqstp->rq_res.len); 414 415 rqstp->rq_res.head[0].iov_len = 0; 416 svc_reserve(rqstp, 0); 417 rqstp->rq_sock = NULL; 418 419 svc_sock_put(svsk); 420 } 421 422 /* 423 * External function to wake up a server waiting for data 424 * This really only makes sense for services like lockd 425 * which have exactly one thread anyway. 426 */ 427 void 428 svc_wake_up(struct svc_serv *serv) 429 { 430 struct svc_rqst *rqstp; 431 unsigned int i; 432 struct svc_pool *pool; 433 434 for (i = 0; i < serv->sv_nrpools; i++) { 435 pool = &serv->sv_pools[i]; 436 437 spin_lock_bh(&pool->sp_lock); 438 if (!list_empty(&pool->sp_threads)) { 439 rqstp = list_entry(pool->sp_threads.next, 440 struct svc_rqst, 441 rq_list); 442 dprintk("svc: daemon %p woken up.\n", rqstp); 443 /* 444 svc_thread_dequeue(pool, rqstp); 445 rqstp->rq_sock = NULL; 446 */ 447 wake_up(&rqstp->rq_wait); 448 } 449 spin_unlock_bh(&pool->sp_lock); 450 } 451 } 452 453 union svc_pktinfo_u { 454 struct in_pktinfo pkti; 455 struct in6_pktinfo pkti6; 456 }; 457 #define SVC_PKTINFO_SPACE \ 458 CMSG_SPACE(sizeof(union svc_pktinfo_u)) 459 460 static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh) 461 { 462 switch (rqstp->rq_sock->sk_sk->sk_family) { 463 case AF_INET: { 464 struct in_pktinfo *pki = CMSG_DATA(cmh); 465 466 cmh->cmsg_level = SOL_IP; 467 cmh->cmsg_type = IP_PKTINFO; 468 pki->ipi_ifindex = 0; 469 pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr; 470 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 471 } 472 break; 473 474 case AF_INET6: { 475 struct in6_pktinfo *pki = CMSG_DATA(cmh); 476 477 cmh->cmsg_level = SOL_IPV6; 478 cmh->cmsg_type = IPV6_PKTINFO; 479 pki->ipi6_ifindex = 0; 480 ipv6_addr_copy(&pki->ipi6_addr, 481 &rqstp->rq_daddr.addr6); 482 cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); 483 } 484 break; 485 } 486 return; 487 } 488 489 /* 490 * Generic sendto routine 491 */ 492 static int 493 svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr) 494 { 495 struct svc_sock *svsk = rqstp->rq_sock; 496 struct socket *sock = svsk->sk_sock; 497 int slen; 498 union { 499 struct cmsghdr hdr; 500 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 501 } buffer; 502 struct cmsghdr *cmh = &buffer.hdr; 503 int len = 0; 504 int result; 505 int size; 506 struct page **ppage = xdr->pages; 507 size_t base = xdr->page_base; 508 unsigned int pglen = xdr->page_len; 509 unsigned int flags = MSG_MORE; 510 char buf[RPC_MAX_ADDRBUFLEN]; 511 512 slen = xdr->len; 513 514 if (rqstp->rq_prot == IPPROTO_UDP) { 515 struct msghdr msg = { 516 .msg_name = &rqstp->rq_addr, 517 .msg_namelen = rqstp->rq_addrlen, 518 .msg_control = cmh, 519 .msg_controllen = sizeof(buffer), 520 .msg_flags = MSG_MORE, 521 }; 522 523 svc_set_cmsg_data(rqstp, cmh); 524 525 if (sock_sendmsg(sock, &msg, 0) < 0) 526 goto out; 527 } 528 529 /* send head */ 530 if (slen == xdr->head[0].iov_len) 531 flags = 0; 532 len = kernel_sendpage(sock, rqstp->rq_respages[0], 0, 533 xdr->head[0].iov_len, flags); 534 if (len != xdr->head[0].iov_len) 535 goto out; 536 slen -= xdr->head[0].iov_len; 537 if (slen == 0) 538 goto out; 539 540 /* send page data */ 541 size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen; 542 while (pglen > 0) { 543 if (slen == size) 544 flags = 0; 545 result = kernel_sendpage(sock, *ppage, base, size, flags); 546 if (result > 0) 547 len += result; 548 if (result != size) 549 goto out; 550 slen -= size; 551 pglen -= size; 552 size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen; 553 base = 0; 554 ppage++; 555 } 556 /* send tail */ 557 if (xdr->tail[0].iov_len) { 558 result = kernel_sendpage(sock, rqstp->rq_respages[0], 559 ((unsigned long)xdr->tail[0].iov_base) 560 & (PAGE_SIZE-1), 561 xdr->tail[0].iov_len, 0); 562 563 if (result > 0) 564 len += result; 565 } 566 out: 567 dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n", 568 rqstp->rq_sock, xdr->head[0].iov_base, xdr->head[0].iov_len, 569 xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf))); 570 571 return len; 572 } 573 574 /* 575 * Report socket names for nfsdfs 576 */ 577 static int one_sock_name(char *buf, struct svc_sock *svsk) 578 { 579 int len; 580 581 switch(svsk->sk_sk->sk_family) { 582 case AF_INET: 583 len = sprintf(buf, "ipv4 %s %u.%u.%u.%u %d\n", 584 svsk->sk_sk->sk_protocol==IPPROTO_UDP? 585 "udp" : "tcp", 586 NIPQUAD(inet_sk(svsk->sk_sk)->rcv_saddr), 587 inet_sk(svsk->sk_sk)->num); 588 break; 589 default: 590 len = sprintf(buf, "*unknown-%d*\n", 591 svsk->sk_sk->sk_family); 592 } 593 return len; 594 } 595 596 int 597 svc_sock_names(char *buf, struct svc_serv *serv, char *toclose) 598 { 599 struct svc_sock *svsk, *closesk = NULL; 600 int len = 0; 601 602 if (!serv) 603 return 0; 604 spin_lock_bh(&serv->sv_lock); 605 list_for_each_entry(svsk, &serv->sv_permsocks, sk_list) { 606 int onelen = one_sock_name(buf+len, svsk); 607 if (toclose && strcmp(toclose, buf+len) == 0) 608 closesk = svsk; 609 else 610 len += onelen; 611 } 612 spin_unlock_bh(&serv->sv_lock); 613 if (closesk) 614 /* Should unregister with portmap, but you cannot 615 * unregister just one protocol... 616 */ 617 svc_close_socket(closesk); 618 else if (toclose) 619 return -ENOENT; 620 return len; 621 } 622 EXPORT_SYMBOL(svc_sock_names); 623 624 /* 625 * Check input queue length 626 */ 627 static int 628 svc_recv_available(struct svc_sock *svsk) 629 { 630 struct socket *sock = svsk->sk_sock; 631 int avail, err; 632 633 err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail); 634 635 return (err >= 0)? avail : err; 636 } 637 638 /* 639 * Generic recvfrom routine. 640 */ 641 static int 642 svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen) 643 { 644 struct svc_sock *svsk = rqstp->rq_sock; 645 struct msghdr msg = { 646 .msg_flags = MSG_DONTWAIT, 647 }; 648 struct sockaddr *sin; 649 int len; 650 651 len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen, 652 msg.msg_flags); 653 654 /* sock_recvmsg doesn't fill in the name/namelen, so we must.. 655 */ 656 memcpy(&rqstp->rq_addr, &svsk->sk_remote, svsk->sk_remotelen); 657 rqstp->rq_addrlen = svsk->sk_remotelen; 658 659 /* Destination address in request is needed for binding the 660 * source address in RPC callbacks later. 661 */ 662 sin = (struct sockaddr *)&svsk->sk_local; 663 switch (sin->sa_family) { 664 case AF_INET: 665 rqstp->rq_daddr.addr = ((struct sockaddr_in *)sin)->sin_addr; 666 break; 667 case AF_INET6: 668 rqstp->rq_daddr.addr6 = ((struct sockaddr_in6 *)sin)->sin6_addr; 669 break; 670 } 671 672 dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n", 673 svsk, iov[0].iov_base, iov[0].iov_len, len); 674 675 return len; 676 } 677 678 /* 679 * Set socket snd and rcv buffer lengths 680 */ 681 static inline void 682 svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv) 683 { 684 #if 0 685 mm_segment_t oldfs; 686 oldfs = get_fs(); set_fs(KERNEL_DS); 687 sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF, 688 (char*)&snd, sizeof(snd)); 689 sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF, 690 (char*)&rcv, sizeof(rcv)); 691 #else 692 /* sock_setsockopt limits use to sysctl_?mem_max, 693 * which isn't acceptable. Until that is made conditional 694 * on not having CAP_SYS_RESOURCE or similar, we go direct... 695 * DaveM said I could! 696 */ 697 lock_sock(sock->sk); 698 sock->sk->sk_sndbuf = snd * 2; 699 sock->sk->sk_rcvbuf = rcv * 2; 700 sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK; 701 release_sock(sock->sk); 702 #endif 703 } 704 /* 705 * INET callback when data has been received on the socket. 706 */ 707 static void 708 svc_udp_data_ready(struct sock *sk, int count) 709 { 710 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 711 712 if (svsk) { 713 dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n", 714 svsk, sk, count, test_bit(SK_BUSY, &svsk->sk_flags)); 715 set_bit(SK_DATA, &svsk->sk_flags); 716 svc_sock_enqueue(svsk); 717 } 718 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 719 wake_up_interruptible(sk->sk_sleep); 720 } 721 722 /* 723 * INET callback when space is newly available on the socket. 724 */ 725 static void 726 svc_write_space(struct sock *sk) 727 { 728 struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); 729 730 if (svsk) { 731 dprintk("svc: socket %p(inet %p), write_space busy=%d\n", 732 svsk, sk, test_bit(SK_BUSY, &svsk->sk_flags)); 733 svc_sock_enqueue(svsk); 734 } 735 736 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) { 737 dprintk("RPC svc_write_space: someone sleeping on %p\n", 738 svsk); 739 wake_up_interruptible(sk->sk_sleep); 740 } 741 } 742 743 static inline void svc_udp_get_dest_address(struct svc_rqst *rqstp, 744 struct cmsghdr *cmh) 745 { 746 switch (rqstp->rq_sock->sk_sk->sk_family) { 747 case AF_INET: { 748 struct in_pktinfo *pki = CMSG_DATA(cmh); 749 rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr; 750 break; 751 } 752 case AF_INET6: { 753 struct in6_pktinfo *pki = CMSG_DATA(cmh); 754 ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr); 755 break; 756 } 757 } 758 } 759 760 /* 761 * Receive a datagram from a UDP socket. 762 */ 763 static int 764 svc_udp_recvfrom(struct svc_rqst *rqstp) 765 { 766 struct svc_sock *svsk = rqstp->rq_sock; 767 struct svc_serv *serv = svsk->sk_server; 768 struct sk_buff *skb; 769 union { 770 struct cmsghdr hdr; 771 long all[SVC_PKTINFO_SPACE / sizeof(long)]; 772 } buffer; 773 struct cmsghdr *cmh = &buffer.hdr; 774 int err, len; 775 struct msghdr msg = { 776 .msg_name = svc_addr(rqstp), 777 .msg_control = cmh, 778 .msg_controllen = sizeof(buffer), 779 .msg_flags = MSG_DONTWAIT, 780 }; 781 782 if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags)) 783 /* udp sockets need large rcvbuf as all pending 784 * requests are still in that buffer. sndbuf must 785 * also be large enough that there is enough space 786 * for one reply per thread. We count all threads 787 * rather than threads in a particular pool, which 788 * provides an upper bound on the number of threads 789 * which will access the socket. 790 */ 791 svc_sock_setbufsize(svsk->sk_sock, 792 (serv->sv_nrthreads+3) * serv->sv_max_mesg, 793 (serv->sv_nrthreads+3) * serv->sv_max_mesg); 794 795 if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) { 796 svc_sock_received(svsk); 797 return svc_deferred_recv(rqstp); 798 } 799 800 if (test_bit(SK_CLOSE, &svsk->sk_flags)) { 801 svc_delete_socket(svsk); 802 return 0; 803 } 804 805 clear_bit(SK_DATA, &svsk->sk_flags); 806 skb = NULL; 807 err = kernel_recvmsg(svsk->sk_sock, &msg, NULL, 808 0, 0, MSG_PEEK | MSG_DONTWAIT); 809 if (err >= 0) 810 skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err); 811 812 if (skb == NULL) { 813 if (err != -EAGAIN) { 814 /* possibly an icmp error */ 815 dprintk("svc: recvfrom returned error %d\n", -err); 816 set_bit(SK_DATA, &svsk->sk_flags); 817 } 818 svc_sock_received(svsk); 819 return -EAGAIN; 820 } 821 rqstp->rq_addrlen = sizeof(rqstp->rq_addr); 822 if (skb->tstamp.tv64 == 0) { 823 skb->tstamp = ktime_get_real(); 824 /* Don't enable netstamp, sunrpc doesn't 825 need that much accuracy */ 826 } 827 svsk->sk_sk->sk_stamp = skb->tstamp; 828 set_bit(SK_DATA, &svsk->sk_flags); /* there may be more data... */ 829 830 /* 831 * Maybe more packets - kick another thread ASAP. 832 */ 833 svc_sock_received(svsk); 834 835 len = skb->len - sizeof(struct udphdr); 836 rqstp->rq_arg.len = len; 837 838 rqstp->rq_prot = IPPROTO_UDP; 839 840 if (cmh->cmsg_level != IPPROTO_IP || 841 cmh->cmsg_type != IP_PKTINFO) { 842 if (net_ratelimit()) 843 printk("rpcsvc: received unknown control message:" 844 "%d/%d\n", 845 cmh->cmsg_level, cmh->cmsg_type); 846 skb_free_datagram(svsk->sk_sk, skb); 847 return 0; 848 } 849 svc_udp_get_dest_address(rqstp, cmh); 850 851 if (skb_is_nonlinear(skb)) { 852 /* we have to copy */ 853 local_bh_disable(); 854 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) { 855 local_bh_enable(); 856 /* checksum error */ 857 skb_free_datagram(svsk->sk_sk, skb); 858 return 0; 859 } 860 local_bh_enable(); 861 skb_free_datagram(svsk->sk_sk, skb); 862 } else { 863 /* we can use it in-place */ 864 rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr); 865 rqstp->rq_arg.head[0].iov_len = len; 866 if (skb_checksum_complete(skb)) { 867 skb_free_datagram(svsk->sk_sk, skb); 868 return 0; 869 } 870 rqstp->rq_skbuff = skb; 871 } 872 873 rqstp->rq_arg.page_base = 0; 874 if (len <= rqstp->rq_arg.head[0].iov_len) { 875 rqstp->rq_arg.head[0].iov_len = len; 876 rqstp->rq_arg.page_len = 0; 877 rqstp->rq_respages = rqstp->rq_pages+1; 878 } else { 879 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; 880 rqstp->rq_respages = rqstp->rq_pages + 1 + 881 DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE); 882 } 883 884 if (serv->sv_stats) 885 serv->sv_stats->netudpcnt++; 886 887 return len; 888 } 889 890 static int 891 svc_udp_sendto(struct svc_rqst *rqstp) 892 { 893 int error; 894 895 error = svc_sendto(rqstp, &rqstp->rq_res); 896 if (error == -ECONNREFUSED) 897 /* ICMP error on earlier request. */ 898 error = svc_sendto(rqstp, &rqstp->rq_res); 899 900 return error; 901 } 902 903 static void 904 svc_udp_init(struct svc_sock *svsk) 905 { 906 int one = 1; 907 mm_segment_t oldfs; 908 909 svsk->sk_sk->sk_data_ready = svc_udp_data_ready; 910 svsk->sk_sk->sk_write_space = svc_write_space; 911 svsk->sk_recvfrom = svc_udp_recvfrom; 912 svsk->sk_sendto = svc_udp_sendto; 913 914 /* initialise setting must have enough space to 915 * receive and respond to one request. 916 * svc_udp_recvfrom will re-adjust if necessary 917 */ 918 svc_sock_setbufsize(svsk->sk_sock, 919 3 * svsk->sk_server->sv_max_mesg, 920 3 * svsk->sk_server->sv_max_mesg); 921 922 set_bit(SK_DATA, &svsk->sk_flags); /* might have come in before data_ready set up */ 923 set_bit(SK_CHNGBUF, &svsk->sk_flags); 924 925 oldfs = get_fs(); 926 set_fs(KERNEL_DS); 927 /* make sure we get destination address info */ 928 svsk->sk_sock->ops->setsockopt(svsk->sk_sock, IPPROTO_IP, IP_PKTINFO, 929 (char __user *)&one, sizeof(one)); 930 set_fs(oldfs); 931 } 932 933 /* 934 * A data_ready event on a listening socket means there's a connection 935 * pending. Do not use state_change as a substitute for it. 936 */ 937 static void 938 svc_tcp_listen_data_ready(struct sock *sk, int count_unused) 939 { 940 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 941 942 dprintk("svc: socket %p TCP (listen) state change %d\n", 943 sk, sk->sk_state); 944 945 /* 946 * This callback may called twice when a new connection 947 * is established as a child socket inherits everything 948 * from a parent LISTEN socket. 949 * 1) data_ready method of the parent socket will be called 950 * when one of child sockets become ESTABLISHED. 951 * 2) data_ready method of the child socket may be called 952 * when it receives data before the socket is accepted. 953 * In case of 2, we should ignore it silently. 954 */ 955 if (sk->sk_state == TCP_LISTEN) { 956 if (svsk) { 957 set_bit(SK_CONN, &svsk->sk_flags); 958 svc_sock_enqueue(svsk); 959 } else 960 printk("svc: socket %p: no user data\n", sk); 961 } 962 963 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 964 wake_up_interruptible_all(sk->sk_sleep); 965 } 966 967 /* 968 * A state change on a connected socket means it's dying or dead. 969 */ 970 static void 971 svc_tcp_state_change(struct sock *sk) 972 { 973 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 974 975 dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n", 976 sk, sk->sk_state, sk->sk_user_data); 977 978 if (!svsk) 979 printk("svc: socket %p: no user data\n", sk); 980 else { 981 set_bit(SK_CLOSE, &svsk->sk_flags); 982 svc_sock_enqueue(svsk); 983 } 984 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 985 wake_up_interruptible_all(sk->sk_sleep); 986 } 987 988 static void 989 svc_tcp_data_ready(struct sock *sk, int count) 990 { 991 struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; 992 993 dprintk("svc: socket %p TCP data ready (svsk %p)\n", 994 sk, sk->sk_user_data); 995 if (svsk) { 996 set_bit(SK_DATA, &svsk->sk_flags); 997 svc_sock_enqueue(svsk); 998 } 999 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 1000 wake_up_interruptible(sk->sk_sleep); 1001 } 1002 1003 static inline int svc_port_is_privileged(struct sockaddr *sin) 1004 { 1005 switch (sin->sa_family) { 1006 case AF_INET: 1007 return ntohs(((struct sockaddr_in *)sin)->sin_port) 1008 < PROT_SOCK; 1009 case AF_INET6: 1010 return ntohs(((struct sockaddr_in6 *)sin)->sin6_port) 1011 < PROT_SOCK; 1012 default: 1013 return 0; 1014 } 1015 } 1016 1017 /* 1018 * Accept a TCP connection 1019 */ 1020 static void 1021 svc_tcp_accept(struct svc_sock *svsk) 1022 { 1023 struct sockaddr_storage addr; 1024 struct sockaddr *sin = (struct sockaddr *) &addr; 1025 struct svc_serv *serv = svsk->sk_server; 1026 struct socket *sock = svsk->sk_sock; 1027 struct socket *newsock; 1028 struct svc_sock *newsvsk; 1029 int err, slen; 1030 char buf[RPC_MAX_ADDRBUFLEN]; 1031 1032 dprintk("svc: tcp_accept %p sock %p\n", svsk, sock); 1033 if (!sock) 1034 return; 1035 1036 clear_bit(SK_CONN, &svsk->sk_flags); 1037 err = kernel_accept(sock, &newsock, O_NONBLOCK); 1038 if (err < 0) { 1039 if (err == -ENOMEM) 1040 printk(KERN_WARNING "%s: no more sockets!\n", 1041 serv->sv_name); 1042 else if (err != -EAGAIN && net_ratelimit()) 1043 printk(KERN_WARNING "%s: accept failed (err %d)!\n", 1044 serv->sv_name, -err); 1045 return; 1046 } 1047 1048 set_bit(SK_CONN, &svsk->sk_flags); 1049 svc_sock_enqueue(svsk); 1050 1051 err = kernel_getpeername(newsock, sin, &slen); 1052 if (err < 0) { 1053 if (net_ratelimit()) 1054 printk(KERN_WARNING "%s: peername failed (err %d)!\n", 1055 serv->sv_name, -err); 1056 goto failed; /* aborted connection or whatever */ 1057 } 1058 1059 /* Ideally, we would want to reject connections from unauthorized 1060 * hosts here, but when we get encryption, the IP of the host won't 1061 * tell us anything. For now just warn about unpriv connections. 1062 */ 1063 if (!svc_port_is_privileged(sin)) { 1064 dprintk(KERN_WARNING 1065 "%s: connect from unprivileged port: %s\n", 1066 serv->sv_name, 1067 __svc_print_addr(sin, buf, sizeof(buf))); 1068 } 1069 dprintk("%s: connect from %s\n", serv->sv_name, 1070 __svc_print_addr(sin, buf, sizeof(buf))); 1071 1072 /* make sure that a write doesn't block forever when 1073 * low on memory 1074 */ 1075 newsock->sk->sk_sndtimeo = HZ*30; 1076 1077 if (!(newsvsk = svc_setup_socket(serv, newsock, &err, 1078 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY)))) 1079 goto failed; 1080 memcpy(&newsvsk->sk_remote, sin, slen); 1081 newsvsk->sk_remotelen = slen; 1082 err = kernel_getsockname(newsock, sin, &slen); 1083 if (unlikely(err < 0)) { 1084 dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err); 1085 slen = offsetof(struct sockaddr, sa_data); 1086 } 1087 memcpy(&newsvsk->sk_local, sin, slen); 1088 1089 svc_sock_received(newsvsk); 1090 1091 /* make sure that we don't have too many active connections. 1092 * If we have, something must be dropped. 1093 * 1094 * There's no point in trying to do random drop here for 1095 * DoS prevention. The NFS clients does 1 reconnect in 15 1096 * seconds. An attacker can easily beat that. 1097 * 1098 * The only somewhat efficient mechanism would be if drop 1099 * old connections from the same IP first. But right now 1100 * we don't even record the client IP in svc_sock. 1101 */ 1102 if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) { 1103 struct svc_sock *svsk = NULL; 1104 spin_lock_bh(&serv->sv_lock); 1105 if (!list_empty(&serv->sv_tempsocks)) { 1106 if (net_ratelimit()) { 1107 /* Try to help the admin */ 1108 printk(KERN_NOTICE "%s: too many open TCP " 1109 "sockets, consider increasing the " 1110 "number of nfsd threads\n", 1111 serv->sv_name); 1112 printk(KERN_NOTICE 1113 "%s: last TCP connect from %s\n", 1114 serv->sv_name, __svc_print_addr(sin, 1115 buf, sizeof(buf))); 1116 } 1117 /* 1118 * Always select the oldest socket. It's not fair, 1119 * but so is life 1120 */ 1121 svsk = list_entry(serv->sv_tempsocks.prev, 1122 struct svc_sock, 1123 sk_list); 1124 set_bit(SK_CLOSE, &svsk->sk_flags); 1125 atomic_inc(&svsk->sk_inuse); 1126 } 1127 spin_unlock_bh(&serv->sv_lock); 1128 1129 if (svsk) { 1130 svc_sock_enqueue(svsk); 1131 svc_sock_put(svsk); 1132 } 1133 1134 } 1135 1136 if (serv->sv_stats) 1137 serv->sv_stats->nettcpconn++; 1138 1139 return; 1140 1141 failed: 1142 sock_release(newsock); 1143 return; 1144 } 1145 1146 /* 1147 * Receive data from a TCP socket. 1148 */ 1149 static int 1150 svc_tcp_recvfrom(struct svc_rqst *rqstp) 1151 { 1152 struct svc_sock *svsk = rqstp->rq_sock; 1153 struct svc_serv *serv = svsk->sk_server; 1154 int len; 1155 struct kvec *vec; 1156 int pnum, vlen; 1157 1158 dprintk("svc: tcp_recv %p data %d conn %d close %d\n", 1159 svsk, test_bit(SK_DATA, &svsk->sk_flags), 1160 test_bit(SK_CONN, &svsk->sk_flags), 1161 test_bit(SK_CLOSE, &svsk->sk_flags)); 1162 1163 if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) { 1164 svc_sock_received(svsk); 1165 return svc_deferred_recv(rqstp); 1166 } 1167 1168 if (test_bit(SK_CLOSE, &svsk->sk_flags)) { 1169 svc_delete_socket(svsk); 1170 return 0; 1171 } 1172 1173 if (svsk->sk_sk->sk_state == TCP_LISTEN) { 1174 svc_tcp_accept(svsk); 1175 svc_sock_received(svsk); 1176 return 0; 1177 } 1178 1179 if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags)) 1180 /* sndbuf needs to have room for one request 1181 * per thread, otherwise we can stall even when the 1182 * network isn't a bottleneck. 1183 * 1184 * We count all threads rather than threads in a 1185 * particular pool, which provides an upper bound 1186 * on the number of threads which will access the socket. 1187 * 1188 * rcvbuf just needs to be able to hold a few requests. 1189 * Normally they will be removed from the queue 1190 * as soon a a complete request arrives. 1191 */ 1192 svc_sock_setbufsize(svsk->sk_sock, 1193 (serv->sv_nrthreads+3) * serv->sv_max_mesg, 1194 3 * serv->sv_max_mesg); 1195 1196 clear_bit(SK_DATA, &svsk->sk_flags); 1197 1198 /* Receive data. If we haven't got the record length yet, get 1199 * the next four bytes. Otherwise try to gobble up as much as 1200 * possible up to the complete record length. 1201 */ 1202 if (svsk->sk_tcplen < 4) { 1203 unsigned long want = 4 - svsk->sk_tcplen; 1204 struct kvec iov; 1205 1206 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen; 1207 iov.iov_len = want; 1208 if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0) 1209 goto error; 1210 svsk->sk_tcplen += len; 1211 1212 if (len < want) { 1213 dprintk("svc: short recvfrom while reading record length (%d of %lu)\n", 1214 len, want); 1215 svc_sock_received(svsk); 1216 return -EAGAIN; /* record header not complete */ 1217 } 1218 1219 svsk->sk_reclen = ntohl(svsk->sk_reclen); 1220 if (!(svsk->sk_reclen & 0x80000000)) { 1221 /* FIXME: technically, a record can be fragmented, 1222 * and non-terminal fragments will not have the top 1223 * bit set in the fragment length header. 1224 * But apparently no known nfs clients send fragmented 1225 * records. */ 1226 if (net_ratelimit()) 1227 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx" 1228 " (non-terminal)\n", 1229 (unsigned long) svsk->sk_reclen); 1230 goto err_delete; 1231 } 1232 svsk->sk_reclen &= 0x7fffffff; 1233 dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen); 1234 if (svsk->sk_reclen > serv->sv_max_mesg) { 1235 if (net_ratelimit()) 1236 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx" 1237 " (large)\n", 1238 (unsigned long) svsk->sk_reclen); 1239 goto err_delete; 1240 } 1241 } 1242 1243 /* Check whether enough data is available */ 1244 len = svc_recv_available(svsk); 1245 if (len < 0) 1246 goto error; 1247 1248 if (len < svsk->sk_reclen) { 1249 dprintk("svc: incomplete TCP record (%d of %d)\n", 1250 len, svsk->sk_reclen); 1251 svc_sock_received(svsk); 1252 return -EAGAIN; /* record not complete */ 1253 } 1254 len = svsk->sk_reclen; 1255 set_bit(SK_DATA, &svsk->sk_flags); 1256 1257 vec = rqstp->rq_vec; 1258 vec[0] = rqstp->rq_arg.head[0]; 1259 vlen = PAGE_SIZE; 1260 pnum = 1; 1261 while (vlen < len) { 1262 vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]); 1263 vec[pnum].iov_len = PAGE_SIZE; 1264 pnum++; 1265 vlen += PAGE_SIZE; 1266 } 1267 rqstp->rq_respages = &rqstp->rq_pages[pnum]; 1268 1269 /* Now receive data */ 1270 len = svc_recvfrom(rqstp, vec, pnum, len); 1271 if (len < 0) 1272 goto error; 1273 1274 dprintk("svc: TCP complete record (%d bytes)\n", len); 1275 rqstp->rq_arg.len = len; 1276 rqstp->rq_arg.page_base = 0; 1277 if (len <= rqstp->rq_arg.head[0].iov_len) { 1278 rqstp->rq_arg.head[0].iov_len = len; 1279 rqstp->rq_arg.page_len = 0; 1280 } else { 1281 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; 1282 } 1283 1284 rqstp->rq_skbuff = NULL; 1285 rqstp->rq_prot = IPPROTO_TCP; 1286 1287 /* Reset TCP read info */ 1288 svsk->sk_reclen = 0; 1289 svsk->sk_tcplen = 0; 1290 1291 svc_sock_received(svsk); 1292 if (serv->sv_stats) 1293 serv->sv_stats->nettcpcnt++; 1294 1295 return len; 1296 1297 err_delete: 1298 svc_delete_socket(svsk); 1299 return -EAGAIN; 1300 1301 error: 1302 if (len == -EAGAIN) { 1303 dprintk("RPC: TCP recvfrom got EAGAIN\n"); 1304 svc_sock_received(svsk); 1305 } else { 1306 printk(KERN_NOTICE "%s: recvfrom returned errno %d\n", 1307 svsk->sk_server->sv_name, -len); 1308 goto err_delete; 1309 } 1310 1311 return len; 1312 } 1313 1314 /* 1315 * Send out data on TCP socket. 1316 */ 1317 static int 1318 svc_tcp_sendto(struct svc_rqst *rqstp) 1319 { 1320 struct xdr_buf *xbufp = &rqstp->rq_res; 1321 int sent; 1322 __be32 reclen; 1323 1324 /* Set up the first element of the reply kvec. 1325 * Any other kvecs that may be in use have been taken 1326 * care of by the server implementation itself. 1327 */ 1328 reclen = htonl(0x80000000|((xbufp->len ) - 4)); 1329 memcpy(xbufp->head[0].iov_base, &reclen, 4); 1330 1331 if (test_bit(SK_DEAD, &rqstp->rq_sock->sk_flags)) 1332 return -ENOTCONN; 1333 1334 sent = svc_sendto(rqstp, &rqstp->rq_res); 1335 if (sent != xbufp->len) { 1336 printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n", 1337 rqstp->rq_sock->sk_server->sv_name, 1338 (sent<0)?"got error":"sent only", 1339 sent, xbufp->len); 1340 set_bit(SK_CLOSE, &rqstp->rq_sock->sk_flags); 1341 svc_sock_enqueue(rqstp->rq_sock); 1342 sent = -EAGAIN; 1343 } 1344 return sent; 1345 } 1346 1347 static void 1348 svc_tcp_init(struct svc_sock *svsk) 1349 { 1350 struct sock *sk = svsk->sk_sk; 1351 struct tcp_sock *tp = tcp_sk(sk); 1352 1353 svsk->sk_recvfrom = svc_tcp_recvfrom; 1354 svsk->sk_sendto = svc_tcp_sendto; 1355 1356 if (sk->sk_state == TCP_LISTEN) { 1357 dprintk("setting up TCP socket for listening\n"); 1358 sk->sk_data_ready = svc_tcp_listen_data_ready; 1359 set_bit(SK_CONN, &svsk->sk_flags); 1360 } else { 1361 dprintk("setting up TCP socket for reading\n"); 1362 sk->sk_state_change = svc_tcp_state_change; 1363 sk->sk_data_ready = svc_tcp_data_ready; 1364 sk->sk_write_space = svc_write_space; 1365 1366 svsk->sk_reclen = 0; 1367 svsk->sk_tcplen = 0; 1368 1369 tp->nonagle = 1; /* disable Nagle's algorithm */ 1370 1371 /* initialise setting must have enough space to 1372 * receive and respond to one request. 1373 * svc_tcp_recvfrom will re-adjust if necessary 1374 */ 1375 svc_sock_setbufsize(svsk->sk_sock, 1376 3 * svsk->sk_server->sv_max_mesg, 1377 3 * svsk->sk_server->sv_max_mesg); 1378 1379 set_bit(SK_CHNGBUF, &svsk->sk_flags); 1380 set_bit(SK_DATA, &svsk->sk_flags); 1381 if (sk->sk_state != TCP_ESTABLISHED) 1382 set_bit(SK_CLOSE, &svsk->sk_flags); 1383 } 1384 } 1385 1386 void 1387 svc_sock_update_bufs(struct svc_serv *serv) 1388 { 1389 /* 1390 * The number of server threads has changed. Update 1391 * rcvbuf and sndbuf accordingly on all sockets 1392 */ 1393 struct list_head *le; 1394 1395 spin_lock_bh(&serv->sv_lock); 1396 list_for_each(le, &serv->sv_permsocks) { 1397 struct svc_sock *svsk = 1398 list_entry(le, struct svc_sock, sk_list); 1399 set_bit(SK_CHNGBUF, &svsk->sk_flags); 1400 } 1401 list_for_each(le, &serv->sv_tempsocks) { 1402 struct svc_sock *svsk = 1403 list_entry(le, struct svc_sock, sk_list); 1404 set_bit(SK_CHNGBUF, &svsk->sk_flags); 1405 } 1406 spin_unlock_bh(&serv->sv_lock); 1407 } 1408 1409 /* 1410 * Receive the next request on any socket. This code is carefully 1411 * organised not to touch any cachelines in the shared svc_serv 1412 * structure, only cachelines in the local svc_pool. 1413 */ 1414 int 1415 svc_recv(struct svc_rqst *rqstp, long timeout) 1416 { 1417 struct svc_sock *svsk = NULL; 1418 struct svc_serv *serv = rqstp->rq_server; 1419 struct svc_pool *pool = rqstp->rq_pool; 1420 int len, i; 1421 int pages; 1422 struct xdr_buf *arg; 1423 DECLARE_WAITQUEUE(wait, current); 1424 1425 dprintk("svc: server %p waiting for data (to = %ld)\n", 1426 rqstp, timeout); 1427 1428 if (rqstp->rq_sock) 1429 printk(KERN_ERR 1430 "svc_recv: service %p, socket not NULL!\n", 1431 rqstp); 1432 if (waitqueue_active(&rqstp->rq_wait)) 1433 printk(KERN_ERR 1434 "svc_recv: service %p, wait queue active!\n", 1435 rqstp); 1436 1437 1438 /* now allocate needed pages. If we get a failure, sleep briefly */ 1439 pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; 1440 for (i=0; i < pages ; i++) 1441 while (rqstp->rq_pages[i] == NULL) { 1442 struct page *p = alloc_page(GFP_KERNEL); 1443 if (!p) 1444 schedule_timeout_uninterruptible(msecs_to_jiffies(500)); 1445 rqstp->rq_pages[i] = p; 1446 } 1447 rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ 1448 BUG_ON(pages >= RPCSVC_MAXPAGES); 1449 1450 /* Make arg->head point to first page and arg->pages point to rest */ 1451 arg = &rqstp->rq_arg; 1452 arg->head[0].iov_base = page_address(rqstp->rq_pages[0]); 1453 arg->head[0].iov_len = PAGE_SIZE; 1454 arg->pages = rqstp->rq_pages + 1; 1455 arg->page_base = 0; 1456 /* save at least one page for response */ 1457 arg->page_len = (pages-2)*PAGE_SIZE; 1458 arg->len = (pages-1)*PAGE_SIZE; 1459 arg->tail[0].iov_len = 0; 1460 1461 try_to_freeze(); 1462 cond_resched(); 1463 if (signalled()) 1464 return -EINTR; 1465 1466 spin_lock_bh(&pool->sp_lock); 1467 if ((svsk = svc_sock_dequeue(pool)) != NULL) { 1468 rqstp->rq_sock = svsk; 1469 atomic_inc(&svsk->sk_inuse); 1470 rqstp->rq_reserved = serv->sv_max_mesg; 1471 atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); 1472 } else { 1473 /* No data pending. Go to sleep */ 1474 svc_thread_enqueue(pool, rqstp); 1475 1476 /* 1477 * We have to be able to interrupt this wait 1478 * to bring down the daemons ... 1479 */ 1480 set_current_state(TASK_INTERRUPTIBLE); 1481 add_wait_queue(&rqstp->rq_wait, &wait); 1482 spin_unlock_bh(&pool->sp_lock); 1483 1484 schedule_timeout(timeout); 1485 1486 try_to_freeze(); 1487 1488 spin_lock_bh(&pool->sp_lock); 1489 remove_wait_queue(&rqstp->rq_wait, &wait); 1490 1491 if (!(svsk = rqstp->rq_sock)) { 1492 svc_thread_dequeue(pool, rqstp); 1493 spin_unlock_bh(&pool->sp_lock); 1494 dprintk("svc: server %p, no data yet\n", rqstp); 1495 return signalled()? -EINTR : -EAGAIN; 1496 } 1497 } 1498 spin_unlock_bh(&pool->sp_lock); 1499 1500 dprintk("svc: server %p, pool %u, socket %p, inuse=%d\n", 1501 rqstp, pool->sp_id, svsk, atomic_read(&svsk->sk_inuse)); 1502 len = svsk->sk_recvfrom(rqstp); 1503 dprintk("svc: got len=%d\n", len); 1504 1505 /* No data, incomplete (TCP) read, or accept() */ 1506 if (len == 0 || len == -EAGAIN) { 1507 rqstp->rq_res.len = 0; 1508 svc_sock_release(rqstp); 1509 return -EAGAIN; 1510 } 1511 svsk->sk_lastrecv = get_seconds(); 1512 clear_bit(SK_OLD, &svsk->sk_flags); 1513 1514 rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp)); 1515 rqstp->rq_chandle.defer = svc_defer; 1516 1517 if (serv->sv_stats) 1518 serv->sv_stats->netcnt++; 1519 return len; 1520 } 1521 1522 /* 1523 * Drop request 1524 */ 1525 void 1526 svc_drop(struct svc_rqst *rqstp) 1527 { 1528 dprintk("svc: socket %p dropped request\n", rqstp->rq_sock); 1529 svc_sock_release(rqstp); 1530 } 1531 1532 /* 1533 * Return reply to client. 1534 */ 1535 int 1536 svc_send(struct svc_rqst *rqstp) 1537 { 1538 struct svc_sock *svsk; 1539 int len; 1540 struct xdr_buf *xb; 1541 1542 if ((svsk = rqstp->rq_sock) == NULL) { 1543 printk(KERN_WARNING "NULL socket pointer in %s:%d\n", 1544 __FILE__, __LINE__); 1545 return -EFAULT; 1546 } 1547 1548 /* release the receive skb before sending the reply */ 1549 svc_release_skb(rqstp); 1550 1551 /* calculate over-all length */ 1552 xb = & rqstp->rq_res; 1553 xb->len = xb->head[0].iov_len + 1554 xb->page_len + 1555 xb->tail[0].iov_len; 1556 1557 /* Grab svsk->sk_mutex to serialize outgoing data. */ 1558 mutex_lock(&svsk->sk_mutex); 1559 if (test_bit(SK_DEAD, &svsk->sk_flags)) 1560 len = -ENOTCONN; 1561 else 1562 len = svsk->sk_sendto(rqstp); 1563 mutex_unlock(&svsk->sk_mutex); 1564 svc_sock_release(rqstp); 1565 1566 if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN) 1567 return 0; 1568 return len; 1569 } 1570 1571 /* 1572 * Timer function to close old temporary sockets, using 1573 * a mark-and-sweep algorithm. 1574 */ 1575 static void 1576 svc_age_temp_sockets(unsigned long closure) 1577 { 1578 struct svc_serv *serv = (struct svc_serv *)closure; 1579 struct svc_sock *svsk; 1580 struct list_head *le, *next; 1581 LIST_HEAD(to_be_aged); 1582 1583 dprintk("svc_age_temp_sockets\n"); 1584 1585 if (!spin_trylock_bh(&serv->sv_lock)) { 1586 /* busy, try again 1 sec later */ 1587 dprintk("svc_age_temp_sockets: busy\n"); 1588 mod_timer(&serv->sv_temptimer, jiffies + HZ); 1589 return; 1590 } 1591 1592 list_for_each_safe(le, next, &serv->sv_tempsocks) { 1593 svsk = list_entry(le, struct svc_sock, sk_list); 1594 1595 if (!test_and_set_bit(SK_OLD, &svsk->sk_flags)) 1596 continue; 1597 if (atomic_read(&svsk->sk_inuse) > 1 || test_bit(SK_BUSY, &svsk->sk_flags)) 1598 continue; 1599 atomic_inc(&svsk->sk_inuse); 1600 list_move(le, &to_be_aged); 1601 set_bit(SK_CLOSE, &svsk->sk_flags); 1602 set_bit(SK_DETACHED, &svsk->sk_flags); 1603 } 1604 spin_unlock_bh(&serv->sv_lock); 1605 1606 while (!list_empty(&to_be_aged)) { 1607 le = to_be_aged.next; 1608 /* fiddling the sk_list node is safe 'cos we're SK_DETACHED */ 1609 list_del_init(le); 1610 svsk = list_entry(le, struct svc_sock, sk_list); 1611 1612 dprintk("queuing svsk %p for closing, %lu seconds old\n", 1613 svsk, get_seconds() - svsk->sk_lastrecv); 1614 1615 /* a thread will dequeue and close it soon */ 1616 svc_sock_enqueue(svsk); 1617 svc_sock_put(svsk); 1618 } 1619 1620 mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); 1621 } 1622 1623 /* 1624 * Initialize socket for RPC use and create svc_sock struct 1625 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF. 1626 */ 1627 static struct svc_sock *svc_setup_socket(struct svc_serv *serv, 1628 struct socket *sock, 1629 int *errp, int flags) 1630 { 1631 struct svc_sock *svsk; 1632 struct sock *inet; 1633 int pmap_register = !(flags & SVC_SOCK_ANONYMOUS); 1634 int is_temporary = flags & SVC_SOCK_TEMPORARY; 1635 1636 dprintk("svc: svc_setup_socket %p\n", sock); 1637 if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) { 1638 *errp = -ENOMEM; 1639 return NULL; 1640 } 1641 1642 inet = sock->sk; 1643 1644 /* Register socket with portmapper */ 1645 if (*errp >= 0 && pmap_register) 1646 *errp = svc_register(serv, inet->sk_protocol, 1647 ntohs(inet_sk(inet)->sport)); 1648 1649 if (*errp < 0) { 1650 kfree(svsk); 1651 return NULL; 1652 } 1653 1654 set_bit(SK_BUSY, &svsk->sk_flags); 1655 inet->sk_user_data = svsk; 1656 svsk->sk_sock = sock; 1657 svsk->sk_sk = inet; 1658 svsk->sk_ostate = inet->sk_state_change; 1659 svsk->sk_odata = inet->sk_data_ready; 1660 svsk->sk_owspace = inet->sk_write_space; 1661 svsk->sk_server = serv; 1662 atomic_set(&svsk->sk_inuse, 1); 1663 svsk->sk_lastrecv = get_seconds(); 1664 spin_lock_init(&svsk->sk_lock); 1665 INIT_LIST_HEAD(&svsk->sk_deferred); 1666 INIT_LIST_HEAD(&svsk->sk_ready); 1667 mutex_init(&svsk->sk_mutex); 1668 1669 /* Initialize the socket */ 1670 if (sock->type == SOCK_DGRAM) 1671 svc_udp_init(svsk); 1672 else 1673 svc_tcp_init(svsk); 1674 1675 spin_lock_bh(&serv->sv_lock); 1676 if (is_temporary) { 1677 set_bit(SK_TEMP, &svsk->sk_flags); 1678 list_add(&svsk->sk_list, &serv->sv_tempsocks); 1679 serv->sv_tmpcnt++; 1680 if (serv->sv_temptimer.function == NULL) { 1681 /* setup timer to age temp sockets */ 1682 setup_timer(&serv->sv_temptimer, svc_age_temp_sockets, 1683 (unsigned long)serv); 1684 mod_timer(&serv->sv_temptimer, 1685 jiffies + svc_conn_age_period * HZ); 1686 } 1687 } else { 1688 clear_bit(SK_TEMP, &svsk->sk_flags); 1689 list_add(&svsk->sk_list, &serv->sv_permsocks); 1690 } 1691 spin_unlock_bh(&serv->sv_lock); 1692 1693 dprintk("svc: svc_setup_socket created %p (inet %p)\n", 1694 svsk, svsk->sk_sk); 1695 1696 return svsk; 1697 } 1698 1699 int svc_addsock(struct svc_serv *serv, 1700 int fd, 1701 char *name_return, 1702 int *proto) 1703 { 1704 int err = 0; 1705 struct socket *so = sockfd_lookup(fd, &err); 1706 struct svc_sock *svsk = NULL; 1707 1708 if (!so) 1709 return err; 1710 if (so->sk->sk_family != AF_INET) 1711 err = -EAFNOSUPPORT; 1712 else if (so->sk->sk_protocol != IPPROTO_TCP && 1713 so->sk->sk_protocol != IPPROTO_UDP) 1714 err = -EPROTONOSUPPORT; 1715 else if (so->state > SS_UNCONNECTED) 1716 err = -EISCONN; 1717 else { 1718 svsk = svc_setup_socket(serv, so, &err, SVC_SOCK_DEFAULTS); 1719 if (svsk) { 1720 svc_sock_received(svsk); 1721 err = 0; 1722 } 1723 } 1724 if (err) { 1725 sockfd_put(so); 1726 return err; 1727 } 1728 if (proto) *proto = so->sk->sk_protocol; 1729 return one_sock_name(name_return, svsk); 1730 } 1731 EXPORT_SYMBOL_GPL(svc_addsock); 1732 1733 /* 1734 * Create socket for RPC service. 1735 */ 1736 static int svc_create_socket(struct svc_serv *serv, int protocol, 1737 struct sockaddr *sin, int len, int flags) 1738 { 1739 struct svc_sock *svsk; 1740 struct socket *sock; 1741 int error; 1742 int type; 1743 char buf[RPC_MAX_ADDRBUFLEN]; 1744 1745 dprintk("svc: svc_create_socket(%s, %d, %s)\n", 1746 serv->sv_program->pg_name, protocol, 1747 __svc_print_addr(sin, buf, sizeof(buf))); 1748 1749 if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) { 1750 printk(KERN_WARNING "svc: only UDP and TCP " 1751 "sockets supported\n"); 1752 return -EINVAL; 1753 } 1754 type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM; 1755 1756 error = sock_create_kern(sin->sa_family, type, protocol, &sock); 1757 if (error < 0) 1758 return error; 1759 1760 svc_reclassify_socket(sock); 1761 1762 if (type == SOCK_STREAM) 1763 sock->sk->sk_reuse = 1; /* allow address reuse */ 1764 error = kernel_bind(sock, sin, len); 1765 if (error < 0) 1766 goto bummer; 1767 1768 if (protocol == IPPROTO_TCP) { 1769 if ((error = kernel_listen(sock, 64)) < 0) 1770 goto bummer; 1771 } 1772 1773 if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) { 1774 svc_sock_received(svsk); 1775 return ntohs(inet_sk(svsk->sk_sk)->sport); 1776 } 1777 1778 bummer: 1779 dprintk("svc: svc_create_socket error = %d\n", -error); 1780 sock_release(sock); 1781 return error; 1782 } 1783 1784 /* 1785 * Remove a dead socket 1786 */ 1787 static void 1788 svc_delete_socket(struct svc_sock *svsk) 1789 { 1790 struct svc_serv *serv; 1791 struct sock *sk; 1792 1793 dprintk("svc: svc_delete_socket(%p)\n", svsk); 1794 1795 serv = svsk->sk_server; 1796 sk = svsk->sk_sk; 1797 1798 sk->sk_state_change = svsk->sk_ostate; 1799 sk->sk_data_ready = svsk->sk_odata; 1800 sk->sk_write_space = svsk->sk_owspace; 1801 1802 spin_lock_bh(&serv->sv_lock); 1803 1804 if (!test_and_set_bit(SK_DETACHED, &svsk->sk_flags)) 1805 list_del_init(&svsk->sk_list); 1806 /* 1807 * We used to delete the svc_sock from whichever list 1808 * it's sk_ready node was on, but we don't actually 1809 * need to. This is because the only time we're called 1810 * while still attached to a queue, the queue itself 1811 * is about to be destroyed (in svc_destroy). 1812 */ 1813 if (!test_and_set_bit(SK_DEAD, &svsk->sk_flags)) { 1814 BUG_ON(atomic_read(&svsk->sk_inuse)<2); 1815 atomic_dec(&svsk->sk_inuse); 1816 if (test_bit(SK_TEMP, &svsk->sk_flags)) 1817 serv->sv_tmpcnt--; 1818 } 1819 1820 spin_unlock_bh(&serv->sv_lock); 1821 } 1822 1823 static void svc_close_socket(struct svc_sock *svsk) 1824 { 1825 set_bit(SK_CLOSE, &svsk->sk_flags); 1826 if (test_and_set_bit(SK_BUSY, &svsk->sk_flags)) 1827 /* someone else will have to effect the close */ 1828 return; 1829 1830 atomic_inc(&svsk->sk_inuse); 1831 svc_delete_socket(svsk); 1832 clear_bit(SK_BUSY, &svsk->sk_flags); 1833 svc_sock_put(svsk); 1834 } 1835 1836 void svc_force_close_socket(struct svc_sock *svsk) 1837 { 1838 set_bit(SK_CLOSE, &svsk->sk_flags); 1839 if (test_bit(SK_BUSY, &svsk->sk_flags)) { 1840 /* Waiting to be processed, but no threads left, 1841 * So just remove it from the waiting list 1842 */ 1843 list_del_init(&svsk->sk_ready); 1844 clear_bit(SK_BUSY, &svsk->sk_flags); 1845 } 1846 svc_close_socket(svsk); 1847 } 1848 1849 /** 1850 * svc_makesock - Make a socket for nfsd and lockd 1851 * @serv: RPC server structure 1852 * @protocol: transport protocol to use 1853 * @port: port to use 1854 * @flags: requested socket characteristics 1855 * 1856 */ 1857 int svc_makesock(struct svc_serv *serv, int protocol, unsigned short port, 1858 int flags) 1859 { 1860 struct sockaddr_in sin = { 1861 .sin_family = AF_INET, 1862 .sin_addr.s_addr = INADDR_ANY, 1863 .sin_port = htons(port), 1864 }; 1865 1866 dprintk("svc: creating socket proto = %d\n", protocol); 1867 return svc_create_socket(serv, protocol, (struct sockaddr *) &sin, 1868 sizeof(sin), flags); 1869 } 1870 1871 /* 1872 * Handle defer and revisit of requests 1873 */ 1874 1875 static void svc_revisit(struct cache_deferred_req *dreq, int too_many) 1876 { 1877 struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle); 1878 struct svc_sock *svsk; 1879 1880 if (too_many) { 1881 svc_sock_put(dr->svsk); 1882 kfree(dr); 1883 return; 1884 } 1885 dprintk("revisit queued\n"); 1886 svsk = dr->svsk; 1887 dr->svsk = NULL; 1888 spin_lock(&svsk->sk_lock); 1889 list_add(&dr->handle.recent, &svsk->sk_deferred); 1890 spin_unlock(&svsk->sk_lock); 1891 set_bit(SK_DEFERRED, &svsk->sk_flags); 1892 svc_sock_enqueue(svsk); 1893 svc_sock_put(svsk); 1894 } 1895 1896 static struct cache_deferred_req * 1897 svc_defer(struct cache_req *req) 1898 { 1899 struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle); 1900 int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len); 1901 struct svc_deferred_req *dr; 1902 1903 if (rqstp->rq_arg.page_len) 1904 return NULL; /* if more than a page, give up FIXME */ 1905 if (rqstp->rq_deferred) { 1906 dr = rqstp->rq_deferred; 1907 rqstp->rq_deferred = NULL; 1908 } else { 1909 int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; 1910 /* FIXME maybe discard if size too large */ 1911 dr = kmalloc(size, GFP_KERNEL); 1912 if (dr == NULL) 1913 return NULL; 1914 1915 dr->handle.owner = rqstp->rq_server; 1916 dr->prot = rqstp->rq_prot; 1917 memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen); 1918 dr->addrlen = rqstp->rq_addrlen; 1919 dr->daddr = rqstp->rq_daddr; 1920 dr->argslen = rqstp->rq_arg.len >> 2; 1921 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2); 1922 } 1923 atomic_inc(&rqstp->rq_sock->sk_inuse); 1924 dr->svsk = rqstp->rq_sock; 1925 1926 dr->handle.revisit = svc_revisit; 1927 return &dr->handle; 1928 } 1929 1930 /* 1931 * recv data from a deferred request into an active one 1932 */ 1933 static int svc_deferred_recv(struct svc_rqst *rqstp) 1934 { 1935 struct svc_deferred_req *dr = rqstp->rq_deferred; 1936 1937 rqstp->rq_arg.head[0].iov_base = dr->args; 1938 rqstp->rq_arg.head[0].iov_len = dr->argslen<<2; 1939 rqstp->rq_arg.page_len = 0; 1940 rqstp->rq_arg.len = dr->argslen<<2; 1941 rqstp->rq_prot = dr->prot; 1942 memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen); 1943 rqstp->rq_addrlen = dr->addrlen; 1944 rqstp->rq_daddr = dr->daddr; 1945 rqstp->rq_respages = rqstp->rq_pages; 1946 return dr->argslen<<2; 1947 } 1948 1949 1950 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk) 1951 { 1952 struct svc_deferred_req *dr = NULL; 1953 1954 if (!test_bit(SK_DEFERRED, &svsk->sk_flags)) 1955 return NULL; 1956 spin_lock(&svsk->sk_lock); 1957 clear_bit(SK_DEFERRED, &svsk->sk_flags); 1958 if (!list_empty(&svsk->sk_deferred)) { 1959 dr = list_entry(svsk->sk_deferred.next, 1960 struct svc_deferred_req, 1961 handle.recent); 1962 list_del_init(&dr->handle.recent); 1963 set_bit(SK_DEFERRED, &svsk->sk_flags); 1964 } 1965 spin_unlock(&svsk->sk_lock); 1966 return dr; 1967 } 1968