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   1 /*
   2  * linux/net/sunrpc/svcsock.c
   3  *
   4  * These are the RPC server socket internals.
   5  *
   6  * The server scheduling algorithm does not always distribute the load
   7  * evenly when servicing a single client. May need to modify the
   8  * svc_xprt_enqueue procedure...
   9  *
  10  * TCP support is largely untested and may be a little slow. The problem
  11  * is that we currently do two separate recvfrom's, one for the 4-byte
  12  * record length, and the second for the actual record. This could possibly
  13  * be improved by always reading a minimum size of around 100 bytes and
  14  * tucking any superfluous bytes away in a temporary store. Still, that
  15  * leaves write requests out in the rain. An alternative may be to peek at
  16  * the first skb in the queue, and if it matches the next TCP sequence
  17  * number, to extract the record marker. Yuck.
  18  *
  19  * Copyright (C) 1995, 1996 Olaf Kirch <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_xprt.xpt_flags.XPT_BUSY prevents a svc_sock being
  60  *      enqueued multiply.
  61  *
  62  *      Some flags can be set to certain values at any time
  63  *      providing that certain rules are followed:
  64  *
  65  *      XPT_CONN, XPT_DATA, can be set or cleared at any time.
  66  *              after a set, svc_xprt_enqueue must be called.
  67  *              after a clear, the socket must be read/accepted
  68  *               if this succeeds, it must be set again.
  69  *      XPT_CLOSE can set at any time. It is never cleared.
  70  *      xpt_ref contains a bias of '1' until XPT_DEAD is set.
  71  *             so when xprt_ref hits zero, we know the transport is dead
  72  *             and no-one is using it.
  73  *      XPT_DEAD can only be set while XPT_BUSY is held which ensures
  74  *             no other thread will be using the socket or will try to
  75  *             set XPT_DEAD.
  76  *
  77  */
  78
  79 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
  80
  81
  82 static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  83                                          int *errp, int flags);
  84 static void             svc_delete_xprt(struct svc_xprt *xprt);
  85 static void             svc_udp_data_ready(struct sock *, int);
  86 static int              svc_udp_recvfrom(struct svc_rqst *);
  87 static int              svc_udp_sendto(struct svc_rqst *);
  88 static void             svc_close_xprt(struct svc_xprt *xprt);
  89 static void             svc_sock_detach(struct svc_xprt *);
  90 static void             svc_sock_free(struct svc_xprt *);
  91
  92 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk);
  93 static int svc_deferred_recv(struct svc_rqst *rqstp);
  94 static struct cache_deferred_req *svc_defer(struct cache_req *req);
  95 static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  96                                           struct sockaddr *, int, int);
  97
  98 /* apparently the "standard" is that clients close
  99  * idle connections after 5 minutes, servers after
 100  * 6 minutes
 101  *   http://www.connectathon.org/talks96/nfstcp.pdf
 102  */
 103 static int svc_conn_age_period = 6*60;
 104
 105 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 106 static struct lock_class_key svc_key[2];
 107 static struct lock_class_key svc_slock_key[2];
 108
 109 static inline void svc_reclassify_socket(struct socket *sock)
 110 {
 111         struct sock *sk = sock->sk;
 112         BUG_ON(sock_owned_by_user(sk));
 113         switch (sk->sk_family) {
 114         case AF_INET:
 115                 sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
 116                                               &svc_slock_key[0],
 117                                               "sk_xprt.xpt_lock-AF_INET-NFSD",
 118                                               &svc_key[0]);
 119                 break;
 120
 121         case AF_INET6:
 122                 sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
 123                                               &svc_slock_key[1],
 124                                               "sk_xprt.xpt_lock-AF_INET6-NFSD",
 125                                               &svc_key[1]);
 126                 break;
 127
 128         default:
 129                 BUG();
 130         }
 131 }
 132 #else
 133 static inline void svc_reclassify_socket(struct socket *sock)
 134 {
 135 }
 136 #endif
 137
 138 static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len)
 139 {
 140         switch (addr->sa_family) {
 141         case AF_INET:
 142                 snprintf(buf, len, "%u.%u.%u.%u, port=%u",
 143                         NIPQUAD(((struct sockaddr_in *) addr)->sin_addr),
 144                         ntohs(((struct sockaddr_in *) addr)->sin_port));
 145                 break;
 146
 147         case AF_INET6:
 148                 snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u",
 149                         NIP6(((struct sockaddr_in6 *) addr)->sin6_addr),
 150                         ntohs(((struct sockaddr_in6 *) addr)->sin6_port));
 151                 break;
 152
 153         default:
 154                 snprintf(buf, len, "unknown address type: %d", addr->sa_family);
 155                 break;
 156         }
 157         return buf;
 158 }
 159
 160 /**
 161  * svc_print_addr - Format rq_addr field for printing
 162  * @rqstp: svc_rqst struct containing address to print
 163  * @buf: target buffer for formatted address
 164  * @len: length of target buffer
 165  *
 166  */
 167 char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
 168 {
 169         return __svc_print_addr(svc_addr(rqstp), buf, len);
 170 }
 171 EXPORT_SYMBOL_GPL(svc_print_addr);
 172
 173 /*
 174  * Queue up an idle server thread.  Must have pool->sp_lock held.
 175  * Note: this is really a stack rather than a queue, so that we only
 176  * use as many different threads as we need, and the rest don't pollute
 177  * the cache.
 178  */
 179 static inline void
 180 svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp)
 181 {
 182         list_add(&rqstp->rq_list, &pool->sp_threads);
 183 }
 184
 185 /*
 186  * Dequeue an nfsd thread.  Must have pool->sp_lock held.
 187  */
 188 static inline void
 189 svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp)
 190 {
 191         list_del(&rqstp->rq_list);
 192 }
 193
 194 /*
 195  * Release an skbuff after use
 196  */
 197 static void svc_release_skb(struct svc_rqst *rqstp)
 198 {
 199         struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 200         struct svc_deferred_req *dr = rqstp->rq_deferred;
 201
 202         if (skb) {
 203                 rqstp->rq_xprt_ctxt = NULL;
 204
 205                 dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 206                 skb_free_datagram(rqstp->rq_sock->sk_sk, skb);
 207         }
 208         if (dr) {
 209                 rqstp->rq_deferred = NULL;
 210                 kfree(dr);
 211         }
 212 }
 213
 214 /*
 215  * Queue up a socket with data pending. If there are idle nfsd
 216  * processes, wake 'em up.
 217  *
 218  */
 219 void svc_xprt_enqueue(struct svc_xprt *xprt)
 220 {
 221         struct svc_serv *serv = xprt->xpt_server;
 222         struct svc_pool *pool;
 223         struct svc_rqst *rqstp;
 224         int cpu;
 225
 226         if (!(xprt->xpt_flags &
 227               ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
 228                 return;
 229         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
 230                 return;
 231
 232         cpu = get_cpu();
 233         pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
 234         put_cpu();
 235
 236         spin_lock_bh(&pool->sp_lock);
 237
 238         if (!list_empty(&pool->sp_threads) &&
 239             !list_empty(&pool->sp_sockets))
 240                 printk(KERN_ERR
 241                        "svc_xprt_enqueue: "
 242                        "threads and transports both waiting??\n");
 243
 244         if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
 245                 /* Don't enqueue dead sockets */
 246                 dprintk("svc: transport %p is dead, not enqueued\n", xprt);
 247                 goto out_unlock;
 248         }
 249
 250         /* Mark socket as busy. It will remain in this state until the
 251          * server has processed all pending data and put the socket back
 252          * on the idle list.  We update XPT_BUSY atomically because
 253          * it also guards against trying to enqueue the svc_sock twice.
 254          */
 255         if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
 256                 /* Don't enqueue socket while already enqueued */
 257                 dprintk("svc: transport %p busy, not enqueued\n", xprt);
 258                 goto out_unlock;
 259         }
 260         BUG_ON(xprt->xpt_pool != NULL);
 261         xprt->xpt_pool = pool;
 262
 263         /* Handle pending connection */
 264         if (test_bit(XPT_CONN, &xprt->xpt_flags))
 265                 goto process;
 266
 267         /* Handle close in-progress */
 268         if (test_bit(XPT_CLOSE, &xprt->xpt_flags))
 269                 goto process;
 270
 271         /* Check if we have space to reply to a request */
 272         if (!xprt->xpt_ops->xpo_has_wspace(xprt)) {
 273                 /* Don't enqueue while not enough space for reply */
 274                 dprintk("svc: no write space, transport %p  not enqueued\n",
 275                         xprt);
 276                 xprt->xpt_pool = NULL;
 277                 clear_bit(XPT_BUSY, &xprt->xpt_flags);
 278                 goto out_unlock;
 279         }
 280
 281  process:
 282         if (!list_empty(&pool->sp_threads)) {
 283                 rqstp = list_entry(pool->sp_threads.next,
 284                                    struct svc_rqst,
 285                                    rq_list);
 286                 dprintk("svc: transport %p served by daemon %p\n",
 287                         xprt, rqstp);
 288                 svc_thread_dequeue(pool, rqstp);
 289                 if (rqstp->rq_xprt)
 290                         printk(KERN_ERR
 291                                 "svc_xprt_enqueue: server %p, rq_xprt=%p!\n",
 292                                 rqstp, rqstp->rq_xprt);
 293                 rqstp->rq_xprt = xprt;
 294                 svc_xprt_get(xprt);
 295                 rqstp->rq_reserved = serv->sv_max_mesg;
 296                 atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
 297                 BUG_ON(xprt->xpt_pool != pool);
 298                 wake_up(&rqstp->rq_wait);
 299         } else {
 300                 dprintk("svc: transport %p put into queue\n", xprt);
 301                 list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
 302                 BUG_ON(xprt->xpt_pool != pool);
 303         }
 304
 305 out_unlock:
 306         spin_unlock_bh(&pool->sp_lock);
 307 }
 308 EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
 309
 310 /*
 311  * Dequeue the first socket.  Must be called with the pool->sp_lock held.
 312  */
 313 static inline struct svc_sock *
 314 svc_sock_dequeue(struct svc_pool *pool)
 315 {
 316         struct svc_sock *svsk;
 317
 318         if (list_empty(&pool->sp_sockets))
 319                 return NULL;
 320
 321         svsk = list_entry(pool->sp_sockets.next,
 322                           struct svc_sock, sk_xprt.xpt_ready);
 323         list_del_init(&svsk->sk_xprt.xpt_ready);
 324
 325         dprintk("svc: socket %p dequeued, inuse=%d\n",
 326                 svsk->sk_sk, atomic_read(&svsk->sk_xprt.xpt_ref.refcount));
 327
 328         return svsk;
 329 }
 330
 331 /*
 332  * svc_xprt_received conditionally queues the transport for processing
 333  * by another thread. The caller must hold the XPT_BUSY bit and must
 334  * not thereafter touch transport data.
 335  *
 336  * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
 337  * insufficient) data.
 338  */
 339 void svc_xprt_received(struct svc_xprt *xprt)
 340 {
 341         BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags));
 342         xprt->xpt_pool = NULL;
 343         clear_bit(XPT_BUSY, &xprt->xpt_flags);
 344         svc_xprt_enqueue(xprt);
 345 }
 346 EXPORT_SYMBOL_GPL(svc_xprt_received);
 347
 348 /**
 349  * svc_reserve - change the space reserved for the reply to a request.
 350  * @rqstp:  The request in question
 351  * @space: new max space to reserve
 352  *
 353  * Each request reserves some space on the output queue of the socket
 354  * to make sure the reply fits.  This function reduces that reserved
 355  * space to be the amount of space used already, plus @space.
 356  *
 357  */
 358 void svc_reserve(struct svc_rqst *rqstp, int space)
 359 {
 360         space += rqstp->rq_res.head[0].iov_len;
 361
 362         if (space < rqstp->rq_reserved) {
 363                 struct svc_xprt *xprt = rqstp->rq_xprt;
 364                 atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
 365                 rqstp->rq_reserved = space;
 366
 367                 svc_xprt_enqueue(xprt);
 368         }
 369 }
 370
 371 static void
 372 svc_sock_release(struct svc_rqst *rqstp)
 373 {
 374         struct svc_sock *svsk = rqstp->rq_sock;
 375
 376         rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
 377
 378         svc_free_res_pages(rqstp);
 379         rqstp->rq_res.page_len = 0;
 380         rqstp->rq_res.page_base = 0;
 381
 382
 383         /* Reset response buffer and release
 384          * the reservation.
 385          * But first, check that enough space was reserved
 386          * for the reply, otherwise we have a bug!
 387          */
 388         if ((rqstp->rq_res.len) >  rqstp->rq_reserved)
 389                 printk(KERN_ERR "RPC request reserved %d but used %d\n",
 390                        rqstp->rq_reserved,
 391                        rqstp->rq_res.len);
 392
 393         rqstp->rq_res.head[0].iov_len = 0;
 394         svc_reserve(rqstp, 0);
 395         rqstp->rq_sock = NULL;
 396
 397         svc_xprt_put(&svsk->sk_xprt);
 398 }
 399
 400 /*
 401  * External function to wake up a server waiting for data
 402  * This really only makes sense for services like lockd
 403  * which have exactly one thread anyway.
 404  */
 405 void
 406 svc_wake_up(struct svc_serv *serv)
 407 {
 408         struct svc_rqst *rqstp;
 409         unsigned int i;
 410         struct svc_pool *pool;
 411
 412         for (i = 0; i < serv->sv_nrpools; i++) {
 413                 pool = &serv->sv_pools[i];
 414
 415                 spin_lock_bh(&pool->sp_lock);
 416                 if (!list_empty(&pool->sp_threads)) {
 417                         rqstp = list_entry(pool->sp_threads.next,
 418                                            struct svc_rqst,
 419                                            rq_list);
 420                         dprintk("svc: daemon %p woken up.\n", rqstp);
 421                         /*
 422                         svc_thread_dequeue(pool, rqstp);
 423                         rqstp->rq_sock = NULL;
 424                          */
 425                         wake_up(&rqstp->rq_wait);
 426                 }
 427                 spin_unlock_bh(&pool->sp_lock);
 428         }
 429 }
 430
 431 union svc_pktinfo_u {
 432         struct in_pktinfo pkti;
 433         struct in6_pktinfo pkti6;
 434 };
 435 #define SVC_PKTINFO_SPACE \
 436         CMSG_SPACE(sizeof(union svc_pktinfo_u))
 437
 438 static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 439 {
 440         switch (rqstp->rq_sock->sk_sk->sk_family) {
 441         case AF_INET: {
 442                         struct in_pktinfo *pki = CMSG_DATA(cmh);
 443
 444                         cmh->cmsg_level = SOL_IP;
 445                         cmh->cmsg_type = IP_PKTINFO;
 446                         pki->ipi_ifindex = 0;
 447                         pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr;
 448                         cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 449                 }
 450                 break;
 451
 452         case AF_INET6: {
 453                         struct in6_pktinfo *pki = CMSG_DATA(cmh);
 454
 455                         cmh->cmsg_level = SOL_IPV6;
 456                         cmh->cmsg_type = IPV6_PKTINFO;
 457                         pki->ipi6_ifindex = 0;
 458                         ipv6_addr_copy(&pki->ipi6_addr,
 459                                         &rqstp->rq_daddr.addr6);
 460                         cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 461                 }
 462                 break;
 463         }
 464         return;
 465 }
 466
 467 /*
 468  * Generic sendto routine
 469  */
 470 static int
 471 svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 472 {
 473         struct svc_sock *svsk = rqstp->rq_sock;
 474         struct socket   *sock = svsk->sk_sock;
 475         int             slen;
 476         union {
 477                 struct cmsghdr  hdr;
 478                 long            all[SVC_PKTINFO_SPACE / sizeof(long)];
 479         } buffer;
 480         struct cmsghdr *cmh = &buffer.hdr;
 481         int             len = 0;
 482         int             result;
 483         int             size;
 484         struct page     **ppage = xdr->pages;
 485         size_t          base = xdr->page_base;
 486         unsigned int    pglen = xdr->page_len;
 487         unsigned int    flags = MSG_MORE;
 488         char            buf[RPC_MAX_ADDRBUFLEN];
 489
 490         slen = xdr->len;
 491
 492         if (rqstp->rq_prot == IPPROTO_UDP) {
 493                 struct msghdr msg = {
 494                         .msg_name       = &rqstp->rq_addr,
 495                         .msg_namelen    = rqstp->rq_addrlen,
 496                         .msg_control    = cmh,
 497                         .msg_controllen = sizeof(buffer),
 498                         .msg_flags      = MSG_MORE,
 499                 };
 500
 501                 svc_set_cmsg_data(rqstp, cmh);
 502
 503                 if (sock_sendmsg(sock, &msg, 0) < 0)
 504                         goto out;
 505         }
 506
 507         /* send head */
 508         if (slen == xdr->head[0].iov_len)
 509                 flags = 0;
 510         len = kernel_sendpage(sock, rqstp->rq_respages[0], 0,
 511                                   xdr->head[0].iov_len, flags);
 512         if (len != xdr->head[0].iov_len)
 513                 goto out;
 514         slen -= xdr->head[0].iov_len;
 515         if (slen == 0)
 516                 goto out;
 517
 518         /* send page data */
 519         size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 520         while (pglen > 0) {
 521                 if (slen == size)
 522                         flags = 0;
 523                 result = kernel_sendpage(sock, *ppage, base, size, flags);
 524                 if (result > 0)
 525                         len += result;
 526                 if (result != size)
 527                         goto out;
 528                 slen -= size;
 529                 pglen -= size;
 530                 size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 531                 base = 0;
 532                 ppage++;
 533         }
 534         /* send tail */
 535         if (xdr->tail[0].iov_len) {
 536                 result = kernel_sendpage(sock, rqstp->rq_respages[0],
 537                                              ((unsigned long)xdr->tail[0].iov_base)
 538                                                 & (PAGE_SIZE-1),
 539                                              xdr->tail[0].iov_len, 0);
 540
 541                 if (result > 0)
 542                         len += result;
 543         }
 544 out:
 545         dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
 546                 rqstp->rq_sock, xdr->head[0].iov_base, xdr->head[0].iov_len,
 547                 xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 548
 549         return len;
 550 }
 551
 552 /*
 553  * Report socket names for nfsdfs
 554  */
 555 static int one_sock_name(char *buf, struct svc_sock *svsk)
 556 {
 557         int len;
 558
 559         switch(svsk->sk_sk->sk_family) {
 560         case AF_INET:
 561                 len = sprintf(buf, "ipv4 %s %u.%u.%u.%u %d\n",
 562                               svsk->sk_sk->sk_protocol==IPPROTO_UDP?
 563                               "udp" : "tcp",
 564                               NIPQUAD(inet_sk(svsk->sk_sk)->rcv_saddr),
 565                               inet_sk(svsk->sk_sk)->num);
 566                 break;
 567         default:
 568                 len = sprintf(buf, "*unknown-%d*\n",
 569                                svsk->sk_sk->sk_family);
 570         }
 571         return len;
 572 }
 573
 574 int
 575 svc_sock_names(char *buf, struct svc_serv *serv, char *toclose)
 576 {
 577         struct svc_sock *svsk, *closesk = NULL;
 578         int len = 0;
 579
 580         if (!serv)
 581                 return 0;
 582         spin_lock_bh(&serv->sv_lock);
 583         list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
 584                 int onelen = one_sock_name(buf+len, svsk);
 585                 if (toclose && strcmp(toclose, buf+len) == 0)
 586                         closesk = svsk;
 587                 else
 588                         len += onelen;
 589         }
 590         spin_unlock_bh(&serv->sv_lock);
 591         if (closesk)
 592                 /* Should unregister with portmap, but you cannot
 593                  * unregister just one protocol...
 594                  */
 595                 svc_close_xprt(&closesk->sk_xprt);
 596         else if (toclose)
 597                 return -ENOENT;
 598         return len;
 599 }
 600 EXPORT_SYMBOL(svc_sock_names);
 601
 602 /*
 603  * Check input queue length
 604  */
 605 static int
 606 svc_recv_available(struct svc_sock *svsk)
 607 {
 608         struct socket   *sock = svsk->sk_sock;
 609         int             avail, err;
 610
 611         err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
 612
 613         return (err >= 0)? avail : err;
 614 }
 615
 616 /*
 617  * Generic recvfrom routine.
 618  */
 619 static int
 620 svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen)
 621 {
 622         struct svc_sock *svsk = rqstp->rq_sock;
 623         struct msghdr msg = {
 624                 .msg_flags      = MSG_DONTWAIT,
 625         };
 626         struct sockaddr *sin;
 627         int len;
 628
 629         len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
 630                                 msg.msg_flags);
 631
 632         /* sock_recvmsg doesn't fill in the name/namelen, so we must..
 633          */
 634         memcpy(&rqstp->rq_addr, &svsk->sk_remote, svsk->sk_remotelen);
 635         rqstp->rq_addrlen = svsk->sk_remotelen;
 636
 637         /* Destination address in request is needed for binding the
 638          * source address in RPC callbacks later.
 639          */
 640         sin = (struct sockaddr *)&svsk->sk_local;
 641         switch (sin->sa_family) {
 642         case AF_INET:
 643                 rqstp->rq_daddr.addr = ((struct sockaddr_in *)sin)->sin_addr;
 644                 break;
 645         case AF_INET6:
 646                 rqstp->rq_daddr.addr6 = ((struct sockaddr_in6 *)sin)->sin6_addr;
 647                 break;
 648         }
 649
 650         dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
 651                 svsk, iov[0].iov_base, iov[0].iov_len, len);
 652
 653         return len;
 654 }
 655
 656 /*
 657  * Set socket snd and rcv buffer lengths
 658  */
 659 static inline void
 660 svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv)
 661 {
 662 #if 0
 663         mm_segment_t    oldfs;
 664         oldfs = get_fs(); set_fs(KERNEL_DS);
 665         sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
 666                         (char*)&snd, sizeof(snd));
 667         sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 668                         (char*)&rcv, sizeof(rcv));
 669 #else
 670         /* sock_setsockopt limits use to sysctl_?mem_max,
 671          * which isn't acceptable.  Until that is made conditional
 672          * on not having CAP_SYS_RESOURCE or similar, we go direct...
 673          * DaveM said I could!
 674          */
 675         lock_sock(sock->sk);
 676         sock->sk->sk_sndbuf = snd * 2;
 677         sock->sk->sk_rcvbuf = rcv * 2;
 678         sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
 679         release_sock(sock->sk);
 680 #endif
 681 }
 682 /*
 683  * INET callback when data has been received on the socket.
 684  */
 685 static void
 686 svc_udp_data_ready(struct sock *sk, int count)
 687 {
 688         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 689
 690         if (svsk) {
 691                 dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
 692                         svsk, sk, count,
 693                         test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 694                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 695                 svc_xprt_enqueue(&svsk->sk_xprt);
 696         }
 697         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 698                 wake_up_interruptible(sk->sk_sleep);
 699 }
 700
 701 /*
 702  * INET callback when space is newly available on the socket.
 703  */
 704 static void
 705 svc_write_space(struct sock *sk)
 706 {
 707         struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
 708
 709         if (svsk) {
 710                 dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 711                         svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 712                 svc_xprt_enqueue(&svsk->sk_xprt);
 713         }
 714
 715         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) {
 716                 dprintk("RPC svc_write_space: someone sleeping on %p\n",
 717                        svsk);
 718                 wake_up_interruptible(sk->sk_sleep);
 719         }
 720 }
 721
 722 static inline void svc_udp_get_dest_address(struct svc_rqst *rqstp,
 723                                             struct cmsghdr *cmh)
 724 {
 725         switch (rqstp->rq_sock->sk_sk->sk_family) {
 726         case AF_INET: {
 727                 struct in_pktinfo *pki = CMSG_DATA(cmh);
 728                 rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr;
 729                 break;
 730                 }
 731         case AF_INET6: {
 732                 struct in6_pktinfo *pki = CMSG_DATA(cmh);
 733                 ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr);
 734                 break;
 735                 }
 736         }
 737 }
 738
 739 /*
 740  * Receive a datagram from a UDP socket.
 741  */
 742 static int
 743 svc_udp_recvfrom(struct svc_rqst *rqstp)
 744 {
 745         struct svc_sock *svsk = rqstp->rq_sock;
 746         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 747         struct sk_buff  *skb;
 748         union {
 749                 struct cmsghdr  hdr;
 750                 long            all[SVC_PKTINFO_SPACE / sizeof(long)];
 751         } buffer;
 752         struct cmsghdr *cmh = &buffer.hdr;
 753         int             err, len;
 754         struct msghdr msg = {
 755                 .msg_name = svc_addr(rqstp),
 756                 .msg_control = cmh,
 757                 .msg_controllen = sizeof(buffer),
 758                 .msg_flags = MSG_DONTWAIT,
 759         };
 760
 761         if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 762             /* udp sockets need large rcvbuf as all pending
 763              * requests are still in that buffer.  sndbuf must
 764              * also be large enough that there is enough space
 765              * for one reply per thread.  We count all threads
 766              * rather than threads in a particular pool, which
 767              * provides an upper bound on the number of threads
 768              * which will access the socket.
 769              */
 770             svc_sock_setbufsize(svsk->sk_sock,
 771                                 (serv->sv_nrthreads+3) * serv->sv_max_mesg,
 772                                 (serv->sv_nrthreads+3) * serv->sv_max_mesg);
 773
 774         if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
 775                 svc_xprt_received(&svsk->sk_xprt);
 776                 return svc_deferred_recv(rqstp);
 777         }
 778
 779         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 780         skb = NULL;
 781         err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 782                              0, 0, MSG_PEEK | MSG_DONTWAIT);
 783         if (err >= 0)
 784                 skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
 785
 786         if (skb == NULL) {
 787                 if (err != -EAGAIN) {
 788                         /* possibly an icmp error */
 789                         dprintk("svc: recvfrom returned error %d\n", -err);
 790                         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 791                 }
 792                 svc_xprt_received(&svsk->sk_xprt);
 793                 return -EAGAIN;
 794         }
 795         rqstp->rq_addrlen = sizeof(rqstp->rq_addr);
 796         if (skb->tstamp.tv64 == 0) {
 797                 skb->tstamp = ktime_get_real();
 798                 /* Don't enable netstamp, sunrpc doesn't
 799                    need that much accuracy */
 800         }
 801         svsk->sk_sk->sk_stamp = skb->tstamp;
 802         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 803
 804         /*
 805          * Maybe more packets - kick another thread ASAP.
 806          */
 807         svc_xprt_received(&svsk->sk_xprt);
 808
 809         len  = skb->len - sizeof(struct udphdr);
 810         rqstp->rq_arg.len = len;
 811
 812         rqstp->rq_prot = IPPROTO_UDP;
 813
 814         if (cmh->cmsg_level != IPPROTO_IP ||
 815             cmh->cmsg_type != IP_PKTINFO) {
 816                 if (net_ratelimit())
 817                         printk("rpcsvc: received unknown control message:"
 818                                "%d/%d\n",
 819                                cmh->cmsg_level, cmh->cmsg_type);
 820                 skb_free_datagram(svsk->sk_sk, skb);
 821                 return 0;
 822         }
 823         svc_udp_get_dest_address(rqstp, cmh);
 824
 825         if (skb_is_nonlinear(skb)) {
 826                 /* we have to copy */
 827                 local_bh_disable();
 828                 if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 829                         local_bh_enable();
 830                         /* checksum error */
 831                         skb_free_datagram(svsk->sk_sk, skb);
 832                         return 0;
 833                 }
 834                 local_bh_enable();
 835                 skb_free_datagram(svsk->sk_sk, skb);
 836         } else {
 837                 /* we can use it in-place */
 838                 rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr);
 839                 rqstp->rq_arg.head[0].iov_len = len;
 840                 if (skb_checksum_complete(skb)) {
 841                         skb_free_datagram(svsk->sk_sk, skb);
 842                         return 0;
 843                 }
 844                 rqstp->rq_xprt_ctxt = skb;
 845         }
 846
 847         rqstp->rq_arg.page_base = 0;
 848         if (len <= rqstp->rq_arg.head[0].iov_len) {
 849                 rqstp->rq_arg.head[0].iov_len = len;
 850                 rqstp->rq_arg.page_len = 0;
 851                 rqstp->rq_respages = rqstp->rq_pages+1;
 852         } else {
 853                 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 854                 rqstp->rq_respages = rqstp->rq_pages + 1 +
 855                         DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 856         }
 857
 858         if (serv->sv_stats)
 859                 serv->sv_stats->netudpcnt++;
 860
 861         return len;
 862 }
 863
 864 static int
 865 svc_udp_sendto(struct svc_rqst *rqstp)
 866 {
 867         int             error;
 868
 869         error = svc_sendto(rqstp, &rqstp->rq_res);
 870         if (error == -ECONNREFUSED)
 871                 /* ICMP error on earlier request. */
 872                 error = svc_sendto(rqstp, &rqstp->rq_res);
 873
 874         return error;
 875 }
 876
 877 static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
 878 {
 879 }
 880
 881 static int svc_udp_has_wspace(struct svc_xprt *xprt)
 882 {
 883         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 884         struct svc_serv *serv = xprt->xpt_server;
 885         unsigned long required;
 886
 887         /*
 888          * Set the SOCK_NOSPACE flag before checking the available
 889          * sock space.
 890          */
 891         set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 892         required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 893         if (required*2 > sock_wspace(svsk->sk_sk))
 894                 return 0;
 895         clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 896         return 1;
 897 }
 898
 899 static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 900 {
 901         BUG();
 902         return NULL;
 903 }
 904
 905 static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 906                                        struct sockaddr *sa, int salen,
 907                                        int flags)
 908 {
 909         return svc_create_socket(serv, IPPROTO_UDP, sa, salen, flags);
 910 }
 911
 912 static struct svc_xprt_ops svc_udp_ops = {
 913         .xpo_create = svc_udp_create,
 914         .xpo_recvfrom = svc_udp_recvfrom,
 915         .xpo_sendto = svc_udp_sendto,
 916         .xpo_release_rqst = svc_release_skb,
 917         .xpo_detach = svc_sock_detach,
 918         .xpo_free = svc_sock_free,
 919         .xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
 920         .xpo_has_wspace = svc_udp_has_wspace,
 921         .xpo_accept = svc_udp_accept,
 922 };
 923
 924 static struct svc_xprt_class svc_udp_class = {
 925         .xcl_name = "udp",
 926         .xcl_owner = THIS_MODULE,
 927         .xcl_ops = &svc_udp_ops,
 928         .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 929 };
 930
 931 static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 932 {
 933         int one = 1;
 934         mm_segment_t oldfs;
 935
 936         svc_xprt_init(&svc_udp_class, &svsk->sk_xprt, serv);
 937         clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 938         svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
 939         svsk->sk_sk->sk_write_space = svc_write_space;
 940
 941         /* initialise setting must have enough space to
 942          * receive and respond to one request.
 943          * svc_udp_recvfrom will re-adjust if necessary
 944          */
 945         svc_sock_setbufsize(svsk->sk_sock,
 946                             3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
 947                             3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
 948
 949         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* might have come in before data_ready set up */
 950         set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 951
 952         oldfs = get_fs();
 953         set_fs(KERNEL_DS);
 954         /* make sure we get destination address info */
 955         svsk->sk_sock->ops->setsockopt(svsk->sk_sock, IPPROTO_IP, IP_PKTINFO,
 956                                        (char __user *)&one, sizeof(one));
 957         set_fs(oldfs);
 958 }
 959
 960 /*
 961  * A data_ready event on a listening socket means there's a connection
 962  * pending. Do not use state_change as a substitute for it.
 963  */
 964 static void
 965 svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
 966 {
 967         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 968
 969         dprintk("svc: socket %p TCP (listen) state change %d\n",
 970                 sk, sk->sk_state);
 971
 972         /*
 973          * This callback may called twice when a new connection
 974          * is established as a child socket inherits everything
 975          * from a parent LISTEN socket.
 976          * 1) data_ready method of the parent socket will be called
 977          *    when one of child sockets become ESTABLISHED.
 978          * 2) data_ready method of the child socket may be called
 979          *    when it receives data before the socket is accepted.
 980          * In case of 2, we should ignore it silently.
 981          */
 982         if (sk->sk_state == TCP_LISTEN) {
 983                 if (svsk) {
 984                         set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 985                         svc_xprt_enqueue(&svsk->sk_xprt);
 986                 } else
 987                         printk("svc: socket %p: no user data\n", sk);
 988         }
 989
 990         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 991                 wake_up_interruptible_all(sk->sk_sleep);
 992 }
 993
 994 /*
 995  * A state change on a connected socket means it's dying or dead.
 996  */
 997 static void
 998 svc_tcp_state_change(struct sock *sk)
 999 {
1000         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
1001
1002         dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
1003                 sk, sk->sk_state, sk->sk_user_data);
1004
1005         if (!svsk)
1006                 printk("svc: socket %p: no user data\n", sk);
1007         else {
1008                 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1009                 svc_xprt_enqueue(&svsk->sk_xprt);
1010         }
1011         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1012                 wake_up_interruptible_all(sk->sk_sleep);
1013 }
1014
1015 static void
1016 svc_tcp_data_ready(struct sock *sk, int count)
1017 {
1018         struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
1019
1020         dprintk("svc: socket %p TCP data ready (svsk %p)\n",
1021                 sk, sk->sk_user_data);
1022         if (svsk) {
1023                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1024                 svc_xprt_enqueue(&svsk->sk_xprt);
1025         }
1026         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1027                 wake_up_interruptible(sk->sk_sleep);
1028 }
1029
1030 static inline int svc_port_is_privileged(struct sockaddr *sin)
1031 {
1032         switch (sin->sa_family) {
1033         case AF_INET:
1034                 return ntohs(((struct sockaddr_in *)sin)->sin_port)
1035                         < PROT_SOCK;
1036         case AF_INET6:
1037                 return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
1038                         < PROT_SOCK;
1039         default:
1040                 return 0;
1041         }
1042 }
1043
1044 /*
1045  * Accept a TCP connection
1046  */
1047 static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
1048 {
1049         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1050         struct sockaddr_storage addr;
1051         struct sockaddr *sin = (struct sockaddr *) &addr;
1052         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1053         struct socket   *sock = svsk->sk_sock;
1054         struct socket   *newsock;
1055         struct svc_sock *newsvsk;
1056         int             err, slen;
1057         char            buf[RPC_MAX_ADDRBUFLEN];
1058
1059         dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
1060         if (!sock)
1061                 return NULL;
1062
1063         clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1064         err = kernel_accept(sock, &newsock, O_NONBLOCK);
1065         if (err < 0) {
1066                 if (err == -ENOMEM)
1067                         printk(KERN_WARNING "%s: no more sockets!\n",
1068                                serv->sv_name);
1069                 else if (err != -EAGAIN && net_ratelimit())
1070                         printk(KERN_WARNING "%s: accept failed (err %d)!\n",
1071                                    serv->sv_name, -err);
1072                 return NULL;
1073         }
1074         set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1075
1076         err = kernel_getpeername(newsock, sin, &slen);
1077         if (err < 0) {
1078                 if (net_ratelimit())
1079                         printk(KERN_WARNING "%s: peername failed (err %d)!\n",
1080                                    serv->sv_name, -err);
1081                 goto failed;            /* aborted connection or whatever */
1082         }
1083
1084         /* Ideally, we would want to reject connections from unauthorized
1085          * hosts here, but when we get encryption, the IP of the host won't
1086          * tell us anything.  For now just warn about unpriv connections.
1087          */
1088         if (!svc_port_is_privileged(sin)) {
1089                 dprintk(KERN_WARNING
1090                         "%s: connect from unprivileged port: %s\n",
1091                         serv->sv_name,
1092                         __svc_print_addr(sin, buf, sizeof(buf)));
1093         }
1094         dprintk("%s: connect from %s\n", serv->sv_name,
1095                 __svc_print_addr(sin, buf, sizeof(buf)));
1096
1097         /* make sure that a write doesn't block forever when
1098          * low on memory
1099          */
1100         newsock->sk->sk_sndtimeo = HZ*30;
1101
1102         if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
1103                                  (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
1104                 goto failed;
1105         memcpy(&newsvsk->sk_remote, sin, slen);
1106         newsvsk->sk_remotelen = slen;
1107         err = kernel_getsockname(newsock, sin, &slen);
1108         if (unlikely(err < 0)) {
1109                 dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
1110                 slen = offsetof(struct sockaddr, sa_data);
1111         }
1112         memcpy(&newsvsk->sk_local, sin, slen);
1113
1114         if (serv->sv_stats)
1115                 serv->sv_stats->nettcpconn++;
1116
1117         return &newsvsk->sk_xprt;
1118
1119 failed:
1120         sock_release(newsock);
1121         return NULL;
1122 }
1123
1124 /*
1125  * Receive data from a TCP socket.
1126  */
1127 static int
1128 svc_tcp_recvfrom(struct svc_rqst *rqstp)
1129 {
1130         struct svc_sock *svsk = rqstp->rq_sock;
1131         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1132         int             len;
1133         struct kvec *vec;
1134         int pnum, vlen;
1135
1136         dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
1137                 svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
1138                 test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
1139                 test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
1140
1141         if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
1142                 svc_xprt_received(&svsk->sk_xprt);
1143                 return svc_deferred_recv(rqstp);
1144         }
1145
1146         if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
1147                 /* sndbuf needs to have room for one request
1148                  * per thread, otherwise we can stall even when the
1149                  * network isn't a bottleneck.
1150                  *
1151                  * We count all threads rather than threads in a
1152                  * particular pool, which provides an upper bound
1153                  * on the number of threads which will access the socket.
1154                  *
1155                  * rcvbuf just needs to be able to hold a few requests.
1156                  * Normally they will be removed from the queue
1157                  * as soon a a complete request arrives.
1158                  */
1159                 svc_sock_setbufsize(svsk->sk_sock,
1160                                     (serv->sv_nrthreads+3) * serv->sv_max_mesg,
1161                                     3 * serv->sv_max_mesg);
1162
1163         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1164
1165         /* Receive data. If we haven't got the record length yet, get
1166          * the next four bytes. Otherwise try to gobble up as much as
1167          * possible up to the complete record length.
1168          */
1169         if (svsk->sk_tcplen < 4) {
1170                 unsigned long   want = 4 - svsk->sk_tcplen;
1171                 struct kvec     iov;
1172
1173                 iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
1174                 iov.iov_len  = want;
1175                 if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
1176                         goto error;
1177                 svsk->sk_tcplen += len;
1178
1179                 if (len < want) {
1180                         dprintk("svc: short recvfrom while reading record length (%d of %lu)\n",
1181                                 len, want);
1182                         svc_xprt_received(&svsk->sk_xprt);
1183                         return -EAGAIN; /* record header not complete */
1184                 }
1185
1186                 svsk->sk_reclen = ntohl(svsk->sk_reclen);
1187                 if (!(svsk->sk_reclen & 0x80000000)) {
1188                         /* FIXME: technically, a record can be fragmented,
1189                          *  and non-terminal fragments will not have the top
1190                          *  bit set in the fragment length header.
1191                          *  But apparently no known nfs clients send fragmented
1192                          *  records. */
1193                         if (net_ratelimit())
1194                                 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx"
1195                                        " (non-terminal)\n",
1196                                        (unsigned long) svsk->sk_reclen);
1197                         goto err_delete;
1198                 }
1199                 svsk->sk_reclen &= 0x7fffffff;
1200                 dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
1201                 if (svsk->sk_reclen > serv->sv_max_mesg) {
1202                         if (net_ratelimit())
1203                                 printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx"
1204                                        " (large)\n",
1205                                        (unsigned long) svsk->sk_reclen);
1206                         goto err_delete;
1207                 }
1208         }
1209
1210         /* Check whether enough data is available */
1211         len = svc_recv_available(svsk);
1212         if (len < 0)
1213                 goto error;
1214
1215         if (len < svsk->sk_reclen) {
1216                 dprintk("svc: incomplete TCP record (%d of %d)\n",
1217                         len, svsk->sk_reclen);
1218                 svc_xprt_received(&svsk->sk_xprt);
1219                 return -EAGAIN; /* record not complete */
1220         }
1221         len = svsk->sk_reclen;
1222         set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1223
1224         vec = rqstp->rq_vec;
1225         vec[0] = rqstp->rq_arg.head[0];
1226         vlen = PAGE_SIZE;
1227         pnum = 1;
1228         while (vlen < len) {
1229                 vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]);
1230                 vec[pnum].iov_len = PAGE_SIZE;
1231                 pnum++;
1232                 vlen += PAGE_SIZE;
1233         }
1234         rqstp->rq_respages = &rqstp->rq_pages[pnum];
1235
1236         /* Now receive data */
1237         len = svc_recvfrom(rqstp, vec, pnum, len);
1238         if (len < 0)
1239                 goto error;
1240
1241         dprintk("svc: TCP complete record (%d bytes)\n", len);
1242         rqstp->rq_arg.len = len;
1243         rqstp->rq_arg.page_base = 0;
1244         if (len <= rqstp->rq_arg.head[0].iov_len) {
1245                 rqstp->rq_arg.head[0].iov_len = len;
1246                 rqstp->rq_arg.page_len = 0;
1247         } else {
1248                 rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
1249         }
1250
1251         rqstp->rq_xprt_ctxt   = NULL;
1252         rqstp->rq_prot        = IPPROTO_TCP;
1253
1254         /* Reset TCP read info */
1255         svsk->sk_reclen = 0;
1256         svsk->sk_tcplen = 0;
1257
1258         svc_xprt_received(&svsk->sk_xprt);
1259         if (serv->sv_stats)
1260                 serv->sv_stats->nettcpcnt++;
1261
1262         return len;
1263
1264  err_delete:
1265         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1266         return -EAGAIN;
1267
1268  error:
1269         if (len == -EAGAIN) {
1270                 dprintk("RPC: TCP recvfrom got EAGAIN\n");
1271                 svc_xprt_received(&svsk->sk_xprt);
1272         } else {
1273                 printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
1274                        svsk->sk_xprt.xpt_server->sv_name, -len);
1275                 goto err_delete;
1276         }
1277
1278         return len;
1279 }
1280
1281 /*
1282  * Send out data on TCP socket.
1283  */
1284 static int
1285 svc_tcp_sendto(struct svc_rqst *rqstp)
1286 {
1287         struct xdr_buf  *xbufp = &rqstp->rq_res;
1288         int sent;
1289         __be32 reclen;
1290
1291         /* Set up the first element of the reply kvec.
1292          * Any other kvecs that may be in use have been taken
1293          * care of by the server implementation itself.
1294          */
1295         reclen = htonl(0x80000000|((xbufp->len ) - 4));
1296         memcpy(xbufp->head[0].iov_base, &reclen, 4);
1297
1298         if (test_bit(XPT_DEAD, &rqstp->rq_sock->sk_xprt.xpt_flags))
1299                 return -ENOTCONN;
1300
1301         sent = svc_sendto(rqstp, &rqstp->rq_res);
1302         if (sent != xbufp->len) {
1303                 printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n",
1304                        rqstp->rq_sock->sk_xprt.xpt_server->sv_name,
1305                        (sent<0)?"got error":"sent only",
1306                        sent, xbufp->len);
1307                 set_bit(XPT_CLOSE, &rqstp->rq_sock->sk_xprt.xpt_flags);
1308                 svc_xprt_enqueue(rqstp->rq_xprt);
1309                 sent = -EAGAIN;
1310         }
1311         return sent;
1312 }
1313
1314 /*
1315  * Setup response header. TCP has a 4B record length field.
1316  */
1317 static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
1318 {
1319         struct kvec *resv = &rqstp->rq_res.head[0];
1320
1321         /* tcp needs a space for the record length... */
1322         svc_putnl(resv, 0);
1323 }
1324
1325 static int svc_tcp_has_wspace(struct svc_xprt *xprt)
1326 {
1327         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1328         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
1329         int required;
1330         int wspace;
1331
1332         /*
1333          * Set the SOCK_NOSPACE flag before checking the available
1334          * sock space.
1335          */
1336         set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1337         required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
1338         wspace = sk_stream_wspace(svsk->sk_sk);
1339
1340         if (wspace < sk_stream_min_wspace(svsk->sk_sk))
1341                 return 0;
1342         if (required * 2 > wspace)
1343                 return 0;
1344
1345         clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1346         return 1;
1347 }
1348
1349 static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1350                                        struct sockaddr *sa, int salen,
1351                                        int flags)
1352 {
1353         return svc_create_socket(serv, IPPROTO_TCP, sa, salen, flags);
1354 }
1355
1356 static struct svc_xprt_ops svc_tcp_ops = {
1357         .xpo_create = svc_tcp_create,
1358         .xpo_recvfrom = svc_tcp_recvfrom,
1359         .xpo_sendto = svc_tcp_sendto,
1360         .xpo_release_rqst = svc_release_skb,
1361         .xpo_detach = svc_sock_detach,
1362         .xpo_free = svc_sock_free,
1363         .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1364         .xpo_has_wspace = svc_tcp_has_wspace,
1365         .xpo_accept = svc_tcp_accept,
1366 };
1367
1368 static struct svc_xprt_class svc_tcp_class = {
1369         .xcl_name = "tcp",
1370         .xcl_owner = THIS_MODULE,
1371         .xcl_ops = &svc_tcp_ops,
1372         .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1373 };
1374
1375 void svc_init_xprt_sock(void)
1376 {
1377         svc_reg_xprt_class(&svc_tcp_class);
1378         svc_reg_xprt_class(&svc_udp_class);
1379 }
1380
1381 void svc_cleanup_xprt_sock(void)
1382 {
1383         svc_unreg_xprt_class(&svc_tcp_class);
1384         svc_unreg_xprt_class(&svc_udp_class);
1385 }
1386
1387 static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1388 {
1389         struct sock     *sk = svsk->sk_sk;
1390         struct tcp_sock *tp = tcp_sk(sk);
1391
1392         svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt, serv);
1393         set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1394         if (sk->sk_state == TCP_LISTEN) {
1395                 dprintk("setting up TCP socket for listening\n");
1396                 set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1397                 sk->sk_data_ready = svc_tcp_listen_data_ready;
1398                 set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1399         } else {
1400                 dprintk("setting up TCP socket for reading\n");
1401                 sk->sk_state_change = svc_tcp_state_change;
1402                 sk->sk_data_ready = svc_tcp_data_ready;
1403                 sk->sk_write_space = svc_write_space;
1404
1405                 svsk->sk_reclen = 0;
1406                 svsk->sk_tcplen = 0;
1407
1408                 tp->nonagle = 1;        /* disable Nagle's algorithm */
1409
1410                 /* initialise setting must have enough space to
1411                  * receive and respond to one request.
1412                  * svc_tcp_recvfrom will re-adjust if necessary
1413                  */
1414                 svc_sock_setbufsize(svsk->sk_sock,
1415                                     3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
1416                                     3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
1417
1418                 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1419                 set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1420                 if (sk->sk_state != TCP_ESTABLISHED)
1421                         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1422         }
1423 }
1424
1425 void
1426 svc_sock_update_bufs(struct svc_serv *serv)
1427 {
1428         /*
1429          * The number of server threads has changed. Update
1430          * rcvbuf and sndbuf accordingly on all sockets
1431          */
1432         struct list_head *le;
1433
1434         spin_lock_bh(&serv->sv_lock);
1435         list_for_each(le, &serv->sv_permsocks) {
1436                 struct svc_sock *svsk =
1437                         list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1438                 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1439         }
1440         list_for_each(le, &serv->sv_tempsocks) {
1441                 struct svc_sock *svsk =
1442                         list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1443                 set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1444         }
1445         spin_unlock_bh(&serv->sv_lock);
1446 }
1447
1448 /*
1449  * Make sure that we don't have too many active connections.  If we
1450  * have, something must be dropped.
1451  *
1452  * There's no point in trying to do random drop here for DoS
1453  * prevention. The NFS clients does 1 reconnect in 15 seconds. An
1454  * attacker can easily beat that.
1455  *
1456  * The only somewhat efficient mechanism would be if drop old
1457  * connections from the same IP first. But right now we don't even
1458  * record the client IP in svc_sock.
1459  */
1460 static void svc_check_conn_limits(struct svc_serv *serv)
1461 {
1462         if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
1463                 struct svc_sock *svsk = NULL;
1464                 spin_lock_bh(&serv->sv_lock);
1465                 if (!list_empty(&serv->sv_tempsocks)) {
1466                         if (net_ratelimit()) {
1467                                 /* Try to help the admin */
1468                                 printk(KERN_NOTICE "%s: too many open TCP "
1469                                        "sockets, consider increasing the "
1470                                        "number of nfsd threads\n",
1471                                        serv->sv_name);
1472                         }
1473                         /*
1474                          * Always select the oldest socket. It's not fair,
1475                          * but so is life
1476                          */
1477                         svsk = list_entry(serv->sv_tempsocks.prev,
1478                                           struct svc_sock,
1479                                           sk_xprt.xpt_list);
1480                         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1481                         svc_xprt_get(&svsk->sk_xprt);
1482                 }
1483                 spin_unlock_bh(&serv->sv_lock);
1484
1485                 if (svsk) {
1486                         svc_xprt_enqueue(&svsk->sk_xprt);
1487                         svc_xprt_put(&svsk->sk_xprt);
1488                 }
1489         }
1490 }
1491
1492 /*
1493  * Receive the next request on any socket.  This code is carefully
1494  * organised not to touch any cachelines in the shared svc_serv
1495  * structure, only cachelines in the local svc_pool.
1496  */
1497 int
1498 svc_recv(struct svc_rqst *rqstp, long timeout)
1499 {
1500         struct svc_sock         *svsk = NULL;
1501         struct svc_serv         *serv = rqstp->rq_server;
1502         struct svc_pool         *pool = rqstp->rq_pool;
1503         int                     len, i;
1504         int                     pages;
1505         struct xdr_buf          *arg;
1506         DECLARE_WAITQUEUE(wait, current);
1507
1508         dprintk("svc: server %p waiting for data (to = %ld)\n",
1509                 rqstp, timeout);
1510
1511         if (rqstp->rq_sock)
1512                 printk(KERN_ERR
1513                         "svc_recv: service %p, socket not NULL!\n",
1514                          rqstp);
1515         if (waitqueue_active(&rqstp->rq_wait))
1516                 printk(KERN_ERR
1517                         "svc_recv: service %p, wait queue active!\n",
1518                          rqstp);
1519
1520
1521         /* now allocate needed pages.  If we get a failure, sleep briefly */
1522         pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE;
1523         for (i=0; i < pages ; i++)
1524                 while (rqstp->rq_pages[i] == NULL) {
1525                         struct page *p = alloc_page(GFP_KERNEL);
1526                         if (!p)
1527                                 schedule_timeout_uninterruptible(msecs_to_jiffies(500));
1528                         rqstp->rq_pages[i] = p;
1529                 }
1530         rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
1531         BUG_ON(pages >= RPCSVC_MAXPAGES);
1532
1533         /* Make arg->head point to first page and arg->pages point to rest */
1534         arg = &rqstp->rq_arg;
1535         arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
1536         arg->head[0].iov_len = PAGE_SIZE;
1537         arg->pages = rqstp->rq_pages + 1;
1538         arg->page_base = 0;
1539         /* save at least one page for response */
1540         arg->page_len = (pages-2)*PAGE_SIZE;
1541         arg->len = (pages-1)*PAGE_SIZE;
1542         arg->tail[0].iov_len = 0;
1543
1544         try_to_freeze();
1545         cond_resched();
1546         if (signalled())
1547                 return -EINTR;
1548
1549         spin_lock_bh(&pool->sp_lock);
1550         if ((svsk = svc_sock_dequeue(pool)) != NULL) {
1551                 rqstp->rq_sock = svsk;
1552                 svc_xprt_get(&svsk->sk_xprt);
1553                 rqstp->rq_reserved = serv->sv_max_mesg;
1554                 atomic_add(rqstp->rq_reserved, &svsk->sk_xprt.xpt_reserved);
1555         } else {
1556                 /* No data pending. Go to sleep */
1557                 svc_thread_enqueue(pool, rqstp);
1558
1559                 /*
1560                  * We have to be able to interrupt this wait
1561                  * to bring down the daemons ...
1562                  */
1563                 set_current_state(TASK_INTERRUPTIBLE);
1564                 add_wait_queue(&rqstp->rq_wait, &wait);
1565                 spin_unlock_bh(&pool->sp_lock);
1566
1567                 schedule_timeout(timeout);
1568
1569                 try_to_freeze();
1570
1571                 spin_lock_bh(&pool->sp_lock);
1572                 remove_wait_queue(&rqstp->rq_wait, &wait);
1573
1574                 if (!(svsk = rqstp->rq_sock)) {
1575                         svc_thread_dequeue(pool, rqstp);
1576                         spin_unlock_bh(&pool->sp_lock);
1577                         dprintk("svc: server %p, no data yet\n", rqstp);
1578                         return signalled()? -EINTR : -EAGAIN;
1579                 }
1580         }
1581         spin_unlock_bh(&pool->sp_lock);
1582
1583         len = 0;
1584         if (test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags)) {
1585                 dprintk("svc_recv: found XPT_CLOSE\n");
1586                 svc_delete_xprt(&svsk->sk_xprt);
1587         } else if (test_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags)) {
1588                 struct svc_xprt *newxpt;
1589                 newxpt = svsk->sk_xprt.xpt_ops->xpo_accept(&svsk->sk_xprt);
1590                 if (newxpt) {
1591                         /*
1592                          * We know this module_get will succeed because the
1593                          * listener holds a reference too
1594                          */
1595                         __module_get(newxpt->xpt_class->xcl_owner);
1596                         svc_check_conn_limits(svsk->sk_xprt.xpt_server);
1597                         svc_xprt_received(newxpt);
1598                 }
1599                 svc_xprt_received(&svsk->sk_xprt);
1600         } else {
1601                 dprintk("svc: server %p, pool %u, socket %p, inuse=%d\n",
1602                         rqstp, pool->sp_id, svsk,
1603                         atomic_read(&svsk->sk_xprt.xpt_ref.refcount));
1604                 len = svsk->sk_xprt.xpt_ops->xpo_recvfrom(rqstp);
1605                 dprintk("svc: got len=%d\n", len);
1606         }
1607
1608         /* No data, incomplete (TCP) read, or accept() */
1609         if (len == 0 || len == -EAGAIN) {
1610                 rqstp->rq_res.len = 0;
1611                 svc_sock_release(rqstp);
1612                 return -EAGAIN;
1613         }
1614         clear_bit(XPT_OLD, &svsk->sk_xprt.xpt_flags);
1615
1616         rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp));
1617         rqstp->rq_chandle.defer = svc_defer;
1618
1619         if (serv->sv_stats)
1620                 serv->sv_stats->netcnt++;
1621         return len;
1622 }
1623
1624 /*
1625  * Drop request
1626  */
1627 void
1628 svc_drop(struct svc_rqst *rqstp)
1629 {
1630         dprintk("svc: socket %p dropped request\n", rqstp->rq_sock);
1631         svc_sock_release(rqstp);
1632 }
1633
1634 /*
1635  * Return reply to client.
1636  */
1637 int
1638 svc_send(struct svc_rqst *rqstp)
1639 {
1640         struct svc_xprt *xprt;
1641         int             len;
1642         struct xdr_buf  *xb;
1643
1644         xprt = rqstp->rq_xprt;
1645         if (!xprt)
1646                 return -EFAULT;
1647
1648         /* release the receive skb before sending the reply */
1649         rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
1650
1651         /* calculate over-all length */
1652         xb = & rqstp->rq_res;
1653         xb->len = xb->head[0].iov_len +
1654                 xb->page_len +
1655                 xb->tail[0].iov_len;
1656
1657         /* Grab mutex to serialize outgoing data. */
1658         mutex_lock(&xprt->xpt_mutex);
1659         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
1660                 len = -ENOTCONN;
1661         else
1662                 len = xprt->xpt_ops->xpo_sendto(rqstp);
1663         mutex_unlock(&xprt->xpt_mutex);
1664         svc_sock_release(rqstp);
1665
1666         if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
1667                 return 0;
1668         return len;
1669 }
1670
1671 /*
1672  * Timer function to close old temporary sockets, using
1673  * a mark-and-sweep algorithm.
1674  */
1675 static void
1676 svc_age_temp_sockets(unsigned long closure)
1677 {
1678         struct svc_serv *serv = (struct svc_serv *)closure;
1679         struct svc_sock *svsk;
1680         struct list_head *le, *next;
1681         LIST_HEAD(to_be_aged);
1682
1683         dprintk("svc_age_temp_sockets\n");
1684
1685         if (!spin_trylock_bh(&serv->sv_lock)) {
1686                 /* busy, try again 1 sec later */
1687                 dprintk("svc_age_temp_sockets: busy\n");
1688                 mod_timer(&serv->sv_temptimer, jiffies + HZ);
1689                 return;
1690         }
1691
1692         list_for_each_safe(le, next, &serv->sv_tempsocks) {
1693                 svsk = list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1694
1695                 if (!test_and_set_bit(XPT_OLD, &svsk->sk_xprt.xpt_flags))
1696                         continue;
1697                 if (atomic_read(&svsk->sk_xprt.xpt_ref.refcount) > 1
1698                     || test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags))
1699                         continue;
1700                 svc_xprt_get(&svsk->sk_xprt);
1701                 list_move(le, &to_be_aged);
1702                 set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1703                 set_bit(XPT_DETACHED, &svsk->sk_xprt.xpt_flags);
1704         }
1705         spin_unlock_bh(&serv->sv_lock);
1706
1707         while (!list_empty(&to_be_aged)) {
1708                 le = to_be_aged.next;
1709                 /* fiddling the sk_xprt.xpt_list node is safe 'cos we're XPT_DETACHED */
1710                 list_del_init(le);
1711                 svsk = list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1712
1713                 dprintk("queuing svsk %p for closing\n", svsk);
1714
1715                 /* a thread will dequeue and close it soon */
1716                 svc_xprt_enqueue(&svsk->sk_xprt);
1717                 svc_xprt_put(&svsk->sk_xprt);
1718         }
1719
1720         mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
1721 }
1722
1723 /*
1724  * Initialize socket for RPC use and create svc_sock struct
1725  * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1726  */
1727 static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1728                                                 struct socket *sock,
1729                                                 int *errp, int flags)
1730 {
1731         struct svc_sock *svsk;
1732         struct sock     *inet;
1733         int             pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1734         int             is_temporary = flags & SVC_SOCK_TEMPORARY;
1735
1736         dprintk("svc: svc_setup_socket %p\n", sock);
1737         if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
1738                 *errp = -ENOMEM;
1739                 return NULL;
1740         }
1741
1742         inet = sock->sk;
1743
1744         /* Register socket with portmapper */
1745         if (*errp >= 0 && pmap_register)
1746                 *errp = svc_register(serv, inet->sk_protocol,
1747                                      ntohs(inet_sk(inet)->sport));
1748
1749         if (*errp < 0) {
1750                 kfree(svsk);
1751                 return NULL;
1752         }
1753
1754         set_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags);
1755         inet->sk_user_data = svsk;
1756         svsk->sk_sock = sock;
1757         svsk->sk_sk = inet;
1758         svsk->sk_ostate = inet->sk_state_change;
1759         svsk->sk_odata = inet->sk_data_ready;
1760         svsk->sk_owspace = inet->sk_write_space;
1761         INIT_LIST_HEAD(&svsk->sk_deferred);
1762
1763         /* Initialize the socket */
1764         if (sock->type == SOCK_DGRAM)
1765                 svc_udp_init(svsk, serv);
1766         else
1767                 svc_tcp_init(svsk, serv);
1768
1769         spin_lock_bh(&serv->sv_lock);
1770         if (is_temporary) {
1771                 set_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1772                 list_add(&svsk->sk_xprt.xpt_list, &serv->sv_tempsocks);
1773                 serv->sv_tmpcnt++;
1774                 if (serv->sv_temptimer.function == NULL) {
1775                         /* setup timer to age temp sockets */
1776                         setup_timer(&serv->sv_temptimer, svc_age_temp_sockets,
1777                                         (unsigned long)serv);
1778                         mod_timer(&serv->sv_temptimer,
1779                                         jiffies + svc_conn_age_period * HZ);
1780                 }
1781         } else {
1782                 clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1783                 list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
1784         }
1785         spin_unlock_bh(&serv->sv_lock);
1786
1787         dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1788                                 svsk, svsk->sk_sk);
1789
1790         return svsk;
1791 }
1792
1793 int svc_addsock(struct svc_serv *serv,
1794                 int fd,
1795                 char *name_return,
1796                 int *proto)
1797 {
1798         int err = 0;
1799         struct socket *so = sockfd_lookup(fd, &err);
1800         struct svc_sock *svsk = NULL;
1801
1802         if (!so)
1803                 return err;
1804         if (so->sk->sk_family != AF_INET)
1805                 err =  -EAFNOSUPPORT;
1806         else if (so->sk->sk_protocol != IPPROTO_TCP &&
1807             so->sk->sk_protocol != IPPROTO_UDP)
1808                 err =  -EPROTONOSUPPORT;
1809         else if (so->state > SS_UNCONNECTED)
1810                 err = -EISCONN;
1811         else {
1812                 svsk = svc_setup_socket(serv, so, &err, SVC_SOCK_DEFAULTS);
1813                 if (svsk) {
1814                         svc_xprt_received(&svsk->sk_xprt);
1815                         err = 0;
1816                 }
1817         }
1818         if (err) {
1819                 sockfd_put(so);
1820                 return err;
1821         }
1822         if (proto) *proto = so->sk->sk_protocol;
1823         return one_sock_name(name_return, svsk);
1824 }
1825 EXPORT_SYMBOL_GPL(svc_addsock);
1826
1827 /*
1828  * Create socket for RPC service.
1829  */
1830 static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1831                                           int protocol,
1832                                           struct sockaddr *sin, int len,
1833                                           int flags)
1834 {
1835         struct svc_sock *svsk;
1836         struct socket   *sock;
1837         int             error;
1838         int             type;
1839         char            buf[RPC_MAX_ADDRBUFLEN];
1840
1841         dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1842                         serv->sv_program->pg_name, protocol,
1843                         __svc_print_addr(sin, buf, sizeof(buf)));
1844
1845         if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1846                 printk(KERN_WARNING "svc: only UDP and TCP "
1847                                 "sockets supported\n");
1848                 return ERR_PTR(-EINVAL);
1849         }
1850         type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1851
1852         error = sock_create_kern(sin->sa_family, type, protocol, &sock);
1853         if (error < 0)
1854                 return ERR_PTR(error);
1855
1856         svc_reclassify_socket(sock);
1857
1858         if (type == SOCK_STREAM)
1859                 sock->sk->sk_reuse = 1;         /* allow address reuse */
1860         error = kernel_bind(sock, sin, len);
1861         if (error < 0)
1862                 goto bummer;
1863
1864         if (protocol == IPPROTO_TCP) {
1865                 if ((error = kernel_listen(sock, 64)) < 0)
1866                         goto bummer;
1867         }
1868
1869         if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
1870                 svc_xprt_received(&svsk->sk_xprt);
1871                 return (struct svc_xprt *)svsk;
1872         }
1873
1874 bummer:
1875         dprintk("svc: svc_create_socket error = %d\n", -error);
1876         sock_release(sock);
1877         return ERR_PTR(error);
1878 }
1879
1880 /*
1881  * Detach the svc_sock from the socket so that no
1882  * more callbacks occur.
1883  */
1884 static void svc_sock_detach(struct svc_xprt *xprt)
1885 {
1886         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1887         struct sock *sk = svsk->sk_sk;
1888
1889         dprintk("svc: svc_sock_detach(%p)\n", svsk);
1890
1891         /* put back the old socket callbacks */
1892         sk->sk_state_change = svsk->sk_ostate;
1893         sk->sk_data_ready = svsk->sk_odata;
1894         sk->sk_write_space = svsk->sk_owspace;
1895 }
1896
1897 /*
1898  * Free the svc_sock's socket resources and the svc_sock itself.
1899  */
1900 static void svc_sock_free(struct svc_xprt *xprt)
1901 {
1902         struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1903         dprintk("svc: svc_sock_free(%p)\n", svsk);
1904
1905         if (svsk->sk_sock->file)
1906                 sockfd_put(svsk->sk_sock);
1907         else
1908                 sock_release(svsk->sk_sock);
1909         kfree(svsk);
1910 }
1911
1912 /*
1913  * Remove a dead transport
1914  */
1915 static void svc_delete_xprt(struct svc_xprt *xprt)
1916 {
1917         struct svc_serv *serv = xprt->xpt_server;
1918
1919         dprintk("svc: svc_delete_xprt(%p)\n", xprt);
1920         xprt->xpt_ops->xpo_detach(xprt);
1921
1922         spin_lock_bh(&serv->sv_lock);
1923         if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags))
1924                 list_del_init(&xprt->xpt_list);
1925         /*
1926          * We used to delete the transport from whichever list
1927          * it's sk_xprt.xpt_ready node was on, but we don't actually
1928          * need to.  This is because the only time we're called
1929          * while still attached to a queue, the queue itself
1930          * is about to be destroyed (in svc_destroy).
1931          */
1932         if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
1933                 BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
1934                 if (test_bit(XPT_TEMP, &xprt->xpt_flags))
1935                         serv->sv_tmpcnt--;
1936                 svc_xprt_put(xprt);
1937         }
1938         spin_unlock_bh(&serv->sv_lock);
1939 }
1940
1941 static void svc_close_xprt(struct svc_xprt *xprt)
1942 {
1943         set_bit(XPT_CLOSE, &xprt->xpt_flags);
1944         if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
1945                 /* someone else will have to effect the close */
1946                 return;
1947
1948         svc_xprt_get(xprt);
1949         svc_delete_xprt(xprt);
1950         clear_bit(XPT_BUSY, &xprt->xpt_flags);
1951         svc_xprt_put(xprt);
1952 }
1953
1954 void svc_close_all(struct list_head *xprt_list)
1955 {
1956         struct svc_xprt *xprt;
1957         struct svc_xprt *tmp;
1958
1959         list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) {
1960                 set_bit(XPT_CLOSE, &xprt->xpt_flags);
1961                 if (test_bit(XPT_BUSY, &xprt->xpt_flags)) {
1962                         /* Waiting to be processed, but no threads left,
1963                          * So just remove it from the waiting list
1964                          */
1965                         list_del_init(&xprt->xpt_ready);
1966                         clear_bit(XPT_BUSY, &xprt->xpt_flags);
1967                 }
1968                 svc_close_xprt(xprt);
1969         }
1970 }
1971
1972 /*
1973  * Handle defer and revisit of requests
1974  */
1975
1976 static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
1977 {
1978         struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle);
1979         struct svc_sock *svsk;
1980
1981         if (too_many) {
1982                 svc_xprt_put(&dr->svsk->sk_xprt);
1983                 kfree(dr);
1984                 return;
1985         }
1986         dprintk("revisit queued\n");
1987         svsk = dr->svsk;
1988         dr->svsk = NULL;
1989         spin_lock(&svsk->sk_xprt.xpt_lock);
1990         list_add(&dr->handle.recent, &svsk->sk_deferred);
1991         spin_unlock(&svsk->sk_xprt.xpt_lock);
1992         set_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
1993         svc_xprt_enqueue(&svsk->sk_xprt);
1994         svc_xprt_put(&svsk->sk_xprt);
1995 }
1996
1997 static struct cache_deferred_req *
1998 svc_defer(struct cache_req *req)
1999 {
2000         struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
2001         int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len);
2002         struct svc_deferred_req *dr;
2003
2004         if (rqstp->rq_arg.page_len)
2005                 return NULL; /* if more than a page, give up FIXME */
2006         if (rqstp->rq_deferred) {
2007                 dr = rqstp->rq_deferred;
2008                 rqstp->rq_deferred = NULL;
2009         } else {
2010                 int skip  = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
2011                 /* FIXME maybe discard if size too large */
2012                 dr = kmalloc(size, GFP_KERNEL);
2013                 if (dr == NULL)
2014                         return NULL;
2015
2016                 dr->handle.owner = rqstp->rq_server;
2017                 dr->prot = rqstp->rq_prot;
2018                 memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
2019                 dr->addrlen = rqstp->rq_addrlen;
2020                 dr->daddr = rqstp->rq_daddr;
2021                 dr->argslen = rqstp->rq_arg.len >> 2;
2022                 memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2);
2023         }
2024         svc_xprt_get(rqstp->rq_xprt);
2025         dr->svsk = rqstp->rq_sock;
2026
2027         dr->handle.revisit = svc_revisit;
2028         return &dr->handle;
2029 }
2030
2031 /*
2032  * recv data from a deferred request into an active one
2033  */
2034 static int svc_deferred_recv(struct svc_rqst *rqstp)
2035 {
2036         struct svc_deferred_req *dr = rqstp->rq_deferred;
2037
2038         rqstp->rq_arg.head[0].iov_base = dr->args;
2039         rqstp->rq_arg.head[0].iov_len = dr->argslen<<2;
2040         rqstp->rq_arg.page_len = 0;
2041         rqstp->rq_arg.len = dr->argslen<<2;
2042         rqstp->rq_prot        = dr->prot;
2043         memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
2044         rqstp->rq_addrlen     = dr->addrlen;
2045         rqstp->rq_daddr       = dr->daddr;
2046         rqstp->rq_respages    = rqstp->rq_pages;
2047         return dr->argslen<<2;
2048 }
2049
2050
2051 static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk)
2052 {
2053         struct svc_deferred_req *dr = NULL;
2054
2055         if (!test_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags))
2056                 return NULL;
2057         spin_lock(&svsk->sk_xprt.xpt_lock);
2058         clear_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
2059         if (!list_empty(&svsk->sk_deferred)) {
2060                 dr = list_entry(svsk->sk_deferred.next,
2061                                 struct svc_deferred_req,
2062                                 handle.recent);
2063                 list_del_init(&dr->handle.recent);
2064                 set_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
2065         }
2066         spin_unlock(&svsk->sk_xprt.xpt_lock);
2067         return dr;
2068 }