linux/net/sunrpc/svcsock.c
<<
>>
Prefs
   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.h>
  42#include <net/tcp_states.h>
  43#include <asm/uaccess.h>
  44#include <asm/ioctls.h>
  45
  46#include <linux/sunrpc/types.h>
  47#include <linux/sunrpc/clnt.h>
  48#include <linux/sunrpc/xdr.h>
  49#include <linux/sunrpc/msg_prot.h>
  50#include <linux/sunrpc/svcsock.h>
  51#include <linux/sunrpc/stats.h>
  52
  53#define RPCDBG_FACILITY RPCDBG_SVCXPRT
  54
  55
  56static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *,
  57                                         int *errp, int flags);
  58static void             svc_udp_data_ready(struct sock *, int);
  59static int              svc_udp_recvfrom(struct svc_rqst *);
  60static int              svc_udp_sendto(struct svc_rqst *);
  61static void             svc_sock_detach(struct svc_xprt *);
  62static void             svc_tcp_sock_detach(struct svc_xprt *);
  63static void             svc_sock_free(struct svc_xprt *);
  64
  65static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
  66                                          struct sockaddr *, int, int);
  67#ifdef CONFIG_DEBUG_LOCK_ALLOC
  68static struct lock_class_key svc_key[2];
  69static struct lock_class_key svc_slock_key[2];
  70
  71static void svc_reclassify_socket(struct socket *sock)
  72{
  73        struct sock *sk = sock->sk;
  74        BUG_ON(sock_owned_by_user(sk));
  75        switch (sk->sk_family) {
  76        case AF_INET:
  77                sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
  78                                              &svc_slock_key[0],
  79                                              "sk_xprt.xpt_lock-AF_INET-NFSD",
  80                                              &svc_key[0]);
  81                break;
  82
  83        case AF_INET6:
  84                sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
  85                                              &svc_slock_key[1],
  86                                              "sk_xprt.xpt_lock-AF_INET6-NFSD",
  87                                              &svc_key[1]);
  88                break;
  89
  90        default:
  91                BUG();
  92        }
  93}
  94#else
  95static void svc_reclassify_socket(struct socket *sock)
  96{
  97}
  98#endif
  99
 100/*
 101 * Release an skbuff after use
 102 */
 103static void svc_release_skb(struct svc_rqst *rqstp)
 104{
 105        struct sk_buff *skb = rqstp->rq_xprt_ctxt;
 106
 107        if (skb) {
 108                struct svc_sock *svsk =
 109                        container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 110                rqstp->rq_xprt_ctxt = NULL;
 111
 112                dprintk("svc: service %p, releasing skb %p\n", rqstp, skb);
 113                skb_free_datagram(svsk->sk_sk, skb);
 114        }
 115}
 116
 117union svc_pktinfo_u {
 118        struct in_pktinfo pkti;
 119        struct in6_pktinfo pkti6;
 120};
 121#define SVC_PKTINFO_SPACE \
 122        CMSG_SPACE(sizeof(union svc_pktinfo_u))
 123
 124static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh)
 125{
 126        struct svc_sock *svsk =
 127                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 128        switch (svsk->sk_sk->sk_family) {
 129        case AF_INET: {
 130                        struct in_pktinfo *pki = CMSG_DATA(cmh);
 131
 132                        cmh->cmsg_level = SOL_IP;
 133                        cmh->cmsg_type = IP_PKTINFO;
 134                        pki->ipi_ifindex = 0;
 135                        pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr;
 136                        cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 137                }
 138                break;
 139
 140        case AF_INET6: {
 141                        struct in6_pktinfo *pki = CMSG_DATA(cmh);
 142
 143                        cmh->cmsg_level = SOL_IPV6;
 144                        cmh->cmsg_type = IPV6_PKTINFO;
 145                        pki->ipi6_ifindex = 0;
 146                        ipv6_addr_copy(&pki->ipi6_addr,
 147                                        &rqstp->rq_daddr.addr6);
 148                        cmh->cmsg_len = CMSG_LEN(sizeof(*pki));
 149                }
 150                break;
 151        }
 152        return;
 153}
 154
 155/*
 156 * Generic sendto routine
 157 */
 158static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr)
 159{
 160        struct svc_sock *svsk =
 161                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 162        struct socket   *sock = svsk->sk_sock;
 163        int             slen;
 164        union {
 165                struct cmsghdr  hdr;
 166                long            all[SVC_PKTINFO_SPACE / sizeof(long)];
 167        } buffer;
 168        struct cmsghdr *cmh = &buffer.hdr;
 169        int             len = 0;
 170        int             result;
 171        int             size;
 172        struct page     **ppage = xdr->pages;
 173        size_t          base = xdr->page_base;
 174        unsigned int    pglen = xdr->page_len;
 175        unsigned int    flags = MSG_MORE;
 176        RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 177
 178        slen = xdr->len;
 179
 180        if (rqstp->rq_prot == IPPROTO_UDP) {
 181                struct msghdr msg = {
 182                        .msg_name       = &rqstp->rq_addr,
 183                        .msg_namelen    = rqstp->rq_addrlen,
 184                        .msg_control    = cmh,
 185                        .msg_controllen = sizeof(buffer),
 186                        .msg_flags      = MSG_MORE,
 187                };
 188
 189                svc_set_cmsg_data(rqstp, cmh);
 190
 191                if (sock_sendmsg(sock, &msg, 0) < 0)
 192                        goto out;
 193        }
 194
 195        /* send head */
 196        if (slen == xdr->head[0].iov_len)
 197                flags = 0;
 198        len = kernel_sendpage(sock, rqstp->rq_respages[0], 0,
 199                                  xdr->head[0].iov_len, flags);
 200        if (len != xdr->head[0].iov_len)
 201                goto out;
 202        slen -= xdr->head[0].iov_len;
 203        if (slen == 0)
 204                goto out;
 205
 206        /* send page data */
 207        size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen;
 208        while (pglen > 0) {
 209                if (slen == size)
 210                        flags = 0;
 211                result = kernel_sendpage(sock, *ppage, base, size, flags);
 212                if (result > 0)
 213                        len += result;
 214                if (result != size)
 215                        goto out;
 216                slen -= size;
 217                pglen -= size;
 218                size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen;
 219                base = 0;
 220                ppage++;
 221        }
 222        /* send tail */
 223        if (xdr->tail[0].iov_len) {
 224                result = kernel_sendpage(sock, rqstp->rq_respages[0],
 225                                             ((unsigned long)xdr->tail[0].iov_base)
 226                                                & (PAGE_SIZE-1),
 227                                             xdr->tail[0].iov_len, 0);
 228
 229                if (result > 0)
 230                        len += result;
 231        }
 232out:
 233        dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n",
 234                svsk, xdr->head[0].iov_base, xdr->head[0].iov_len,
 235                xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf)));
 236
 237        return len;
 238}
 239
 240/*
 241 * Report socket names for nfsdfs
 242 */
 243static int one_sock_name(char *buf, struct svc_sock *svsk)
 244{
 245        int len;
 246
 247        switch(svsk->sk_sk->sk_family) {
 248        case AF_INET:
 249                len = sprintf(buf, "ipv4 %s %pI4 %d\n",
 250                              svsk->sk_sk->sk_protocol == IPPROTO_UDP ?
 251                              "udp" : "tcp",
 252                              &inet_sk(svsk->sk_sk)->rcv_saddr,
 253                              inet_sk(svsk->sk_sk)->num);
 254                break;
 255        default:
 256                len = sprintf(buf, "*unknown-%d*\n",
 257                               svsk->sk_sk->sk_family);
 258        }
 259        return len;
 260}
 261
 262int
 263svc_sock_names(char *buf, struct svc_serv *serv, char *toclose)
 264{
 265        struct svc_sock *svsk, *closesk = NULL;
 266        int len = 0;
 267
 268        if (!serv)
 269                return 0;
 270        spin_lock_bh(&serv->sv_lock);
 271        list_for_each_entry(svsk, &serv->sv_permsocks, sk_xprt.xpt_list) {
 272                int onelen = one_sock_name(buf+len, svsk);
 273                if (toclose && strcmp(toclose, buf+len) == 0)
 274                        closesk = svsk;
 275                else
 276                        len += onelen;
 277        }
 278        spin_unlock_bh(&serv->sv_lock);
 279        if (closesk)
 280                /* Should unregister with portmap, but you cannot
 281                 * unregister just one protocol...
 282                 */
 283                svc_close_xprt(&closesk->sk_xprt);
 284        else if (toclose)
 285                return -ENOENT;
 286        return len;
 287}
 288EXPORT_SYMBOL_GPL(svc_sock_names);
 289
 290/*
 291 * Check input queue length
 292 */
 293static int svc_recv_available(struct svc_sock *svsk)
 294{
 295        struct socket   *sock = svsk->sk_sock;
 296        int             avail, err;
 297
 298        err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
 299
 300        return (err >= 0)? avail : err;
 301}
 302
 303/*
 304 * Generic recvfrom routine.
 305 */
 306static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
 307                        int buflen)
 308{
 309        struct svc_sock *svsk =
 310                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 311        struct msghdr msg = {
 312                .msg_flags      = MSG_DONTWAIT,
 313        };
 314        int len;
 315
 316        rqstp->rq_xprt_hlen = 0;
 317
 318        len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
 319                                msg.msg_flags);
 320
 321        dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
 322                svsk, iov[0].iov_base, iov[0].iov_len, len);
 323        return len;
 324}
 325
 326/*
 327 * Set socket snd and rcv buffer lengths
 328 */
 329static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
 330                                unsigned int rcv)
 331{
 332#if 0
 333        mm_segment_t    oldfs;
 334        oldfs = get_fs(); set_fs(KERNEL_DS);
 335        sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF,
 336                        (char*)&snd, sizeof(snd));
 337        sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 338                        (char*)&rcv, sizeof(rcv));
 339#else
 340        /* sock_setsockopt limits use to sysctl_?mem_max,
 341         * which isn't acceptable.  Until that is made conditional
 342         * on not having CAP_SYS_RESOURCE or similar, we go direct...
 343         * DaveM said I could!
 344         */
 345        lock_sock(sock->sk);
 346        sock->sk->sk_sndbuf = snd * 2;
 347        sock->sk->sk_rcvbuf = rcv * 2;
 348        sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
 349        release_sock(sock->sk);
 350#endif
 351}
 352/*
 353 * INET callback when data has been received on the socket.
 354 */
 355static void svc_udp_data_ready(struct sock *sk, int count)
 356{
 357        struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 358
 359        if (svsk) {
 360                dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n",
 361                        svsk, sk, count,
 362                        test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 363                set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 364                svc_xprt_enqueue(&svsk->sk_xprt);
 365        }
 366        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 367                wake_up_interruptible(sk->sk_sleep);
 368}
 369
 370/*
 371 * INET callback when space is newly available on the socket.
 372 */
 373static void svc_write_space(struct sock *sk)
 374{
 375        struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data);
 376
 377        if (svsk) {
 378                dprintk("svc: socket %p(inet %p), write_space busy=%d\n",
 379                        svsk, sk, test_bit(XPT_BUSY, &svsk->sk_xprt.xpt_flags));
 380                svc_xprt_enqueue(&svsk->sk_xprt);
 381        }
 382
 383        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) {
 384                dprintk("RPC svc_write_space: someone sleeping on %p\n",
 385                       svsk);
 386                wake_up_interruptible(sk->sk_sleep);
 387        }
 388}
 389
 390/*
 391 * Copy the UDP datagram's destination address to the rqstp structure.
 392 * The 'destination' address in this case is the address to which the
 393 * peer sent the datagram, i.e. our local address. For multihomed
 394 * hosts, this can change from msg to msg. Note that only the IP
 395 * address changes, the port number should remain the same.
 396 */
 397static void svc_udp_get_dest_address(struct svc_rqst *rqstp,
 398                                     struct cmsghdr *cmh)
 399{
 400        struct svc_sock *svsk =
 401                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 402        switch (svsk->sk_sk->sk_family) {
 403        case AF_INET: {
 404                struct in_pktinfo *pki = CMSG_DATA(cmh);
 405                rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr;
 406                break;
 407                }
 408        case AF_INET6: {
 409                struct in6_pktinfo *pki = CMSG_DATA(cmh);
 410                ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr);
 411                break;
 412                }
 413        }
 414}
 415
 416/*
 417 * Receive a datagram from a UDP socket.
 418 */
 419static int svc_udp_recvfrom(struct svc_rqst *rqstp)
 420{
 421        struct svc_sock *svsk =
 422                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 423        struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 424        struct sk_buff  *skb;
 425        union {
 426                struct cmsghdr  hdr;
 427                long            all[SVC_PKTINFO_SPACE / sizeof(long)];
 428        } buffer;
 429        struct cmsghdr *cmh = &buffer.hdr;
 430        int             err, len;
 431        struct msghdr msg = {
 432                .msg_name = svc_addr(rqstp),
 433                .msg_control = cmh,
 434                .msg_controllen = sizeof(buffer),
 435                .msg_flags = MSG_DONTWAIT,
 436        };
 437
 438        if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 439            /* udp sockets need large rcvbuf as all pending
 440             * requests are still in that buffer.  sndbuf must
 441             * also be large enough that there is enough space
 442             * for one reply per thread.  We count all threads
 443             * rather than threads in a particular pool, which
 444             * provides an upper bound on the number of threads
 445             * which will access the socket.
 446             */
 447            svc_sock_setbufsize(svsk->sk_sock,
 448                                (serv->sv_nrthreads+3) * serv->sv_max_mesg,
 449                                (serv->sv_nrthreads+3) * serv->sv_max_mesg);
 450
 451        clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 452        skb = NULL;
 453        err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
 454                             0, 0, MSG_PEEK | MSG_DONTWAIT);
 455        if (err >= 0)
 456                skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err);
 457
 458        if (skb == NULL) {
 459                if (err != -EAGAIN) {
 460                        /* possibly an icmp error */
 461                        dprintk("svc: recvfrom returned error %d\n", -err);
 462                        set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 463                }
 464                svc_xprt_received(&svsk->sk_xprt);
 465                return -EAGAIN;
 466        }
 467        len = svc_addr_len(svc_addr(rqstp));
 468        if (len < 0)
 469                return len;
 470        rqstp->rq_addrlen = len;
 471        if (skb->tstamp.tv64 == 0) {
 472                skb->tstamp = ktime_get_real();
 473                /* Don't enable netstamp, sunrpc doesn't
 474                   need that much accuracy */
 475        }
 476        svsk->sk_sk->sk_stamp = skb->tstamp;
 477        set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */
 478
 479        /*
 480         * Maybe more packets - kick another thread ASAP.
 481         */
 482        svc_xprt_received(&svsk->sk_xprt);
 483
 484        len  = skb->len - sizeof(struct udphdr);
 485        rqstp->rq_arg.len = len;
 486
 487        rqstp->rq_prot = IPPROTO_UDP;
 488
 489        if (cmh->cmsg_level != IPPROTO_IP ||
 490            cmh->cmsg_type != IP_PKTINFO) {
 491                if (net_ratelimit())
 492                        printk("rpcsvc: received unknown control message:"
 493                               "%d/%d\n",
 494                               cmh->cmsg_level, cmh->cmsg_type);
 495                skb_free_datagram(svsk->sk_sk, skb);
 496                return 0;
 497        }
 498        svc_udp_get_dest_address(rqstp, cmh);
 499
 500        if (skb_is_nonlinear(skb)) {
 501                /* we have to copy */
 502                local_bh_disable();
 503                if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) {
 504                        local_bh_enable();
 505                        /* checksum error */
 506                        skb_free_datagram(svsk->sk_sk, skb);
 507                        return 0;
 508                }
 509                local_bh_enable();
 510                skb_free_datagram(svsk->sk_sk, skb);
 511        } else {
 512                /* we can use it in-place */
 513                rqstp->rq_arg.head[0].iov_base = skb->data +
 514                        sizeof(struct udphdr);
 515                rqstp->rq_arg.head[0].iov_len = len;
 516                if (skb_checksum_complete(skb)) {
 517                        skb_free_datagram(svsk->sk_sk, skb);
 518                        return 0;
 519                }
 520                rqstp->rq_xprt_ctxt = skb;
 521        }
 522
 523        rqstp->rq_arg.page_base = 0;
 524        if (len <= rqstp->rq_arg.head[0].iov_len) {
 525                rqstp->rq_arg.head[0].iov_len = len;
 526                rqstp->rq_arg.page_len = 0;
 527                rqstp->rq_respages = rqstp->rq_pages+1;
 528        } else {
 529                rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 530                rqstp->rq_respages = rqstp->rq_pages + 1 +
 531                        DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE);
 532        }
 533
 534        if (serv->sv_stats)
 535                serv->sv_stats->netudpcnt++;
 536
 537        return len;
 538}
 539
 540static int
 541svc_udp_sendto(struct svc_rqst *rqstp)
 542{
 543        int             error;
 544
 545        error = svc_sendto(rqstp, &rqstp->rq_res);
 546        if (error == -ECONNREFUSED)
 547                /* ICMP error on earlier request. */
 548                error = svc_sendto(rqstp, &rqstp->rq_res);
 549
 550        return error;
 551}
 552
 553static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp)
 554{
 555}
 556
 557static int svc_udp_has_wspace(struct svc_xprt *xprt)
 558{
 559        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 560        struct svc_serv *serv = xprt->xpt_server;
 561        unsigned long required;
 562
 563        /*
 564         * Set the SOCK_NOSPACE flag before checking the available
 565         * sock space.
 566         */
 567        set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 568        required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 569        if (required*2 > sock_wspace(svsk->sk_sk))
 570                return 0;
 571        clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 572        return 1;
 573}
 574
 575static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt)
 576{
 577        BUG();
 578        return NULL;
 579}
 580
 581static struct svc_xprt *svc_udp_create(struct svc_serv *serv,
 582                                       struct sockaddr *sa, int salen,
 583                                       int flags)
 584{
 585        return svc_create_socket(serv, IPPROTO_UDP, sa, salen, flags);
 586}
 587
 588static struct svc_xprt_ops svc_udp_ops = {
 589        .xpo_create = svc_udp_create,
 590        .xpo_recvfrom = svc_udp_recvfrom,
 591        .xpo_sendto = svc_udp_sendto,
 592        .xpo_release_rqst = svc_release_skb,
 593        .xpo_detach = svc_sock_detach,
 594        .xpo_free = svc_sock_free,
 595        .xpo_prep_reply_hdr = svc_udp_prep_reply_hdr,
 596        .xpo_has_wspace = svc_udp_has_wspace,
 597        .xpo_accept = svc_udp_accept,
 598};
 599
 600static struct svc_xprt_class svc_udp_class = {
 601        .xcl_name = "udp",
 602        .xcl_owner = THIS_MODULE,
 603        .xcl_ops = &svc_udp_ops,
 604        .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP,
 605};
 606
 607static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
 608{
 609        int one = 1;
 610        mm_segment_t oldfs;
 611
 612        svc_xprt_init(&svc_udp_class, &svsk->sk_xprt, serv);
 613        clear_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
 614        svsk->sk_sk->sk_data_ready = svc_udp_data_ready;
 615        svsk->sk_sk->sk_write_space = svc_write_space;
 616
 617        /* initialise setting must have enough space to
 618         * receive and respond to one request.
 619         * svc_udp_recvfrom will re-adjust if necessary
 620         */
 621        svc_sock_setbufsize(svsk->sk_sock,
 622                            3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
 623                            3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
 624
 625        /* data might have come in before data_ready set up */
 626        set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 627        set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 628
 629        oldfs = get_fs();
 630        set_fs(KERNEL_DS);
 631        /* make sure we get destination address info */
 632        svsk->sk_sock->ops->setsockopt(svsk->sk_sock, IPPROTO_IP, IP_PKTINFO,
 633                                       (char __user *)&one, sizeof(one));
 634        set_fs(oldfs);
 635}
 636
 637/*
 638 * A data_ready event on a listening socket means there's a connection
 639 * pending. Do not use state_change as a substitute for it.
 640 */
 641static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused)
 642{
 643        struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 644
 645        dprintk("svc: socket %p TCP (listen) state change %d\n",
 646                sk, sk->sk_state);
 647
 648        /*
 649         * This callback may called twice when a new connection
 650         * is established as a child socket inherits everything
 651         * from a parent LISTEN socket.
 652         * 1) data_ready method of the parent socket will be called
 653         *    when one of child sockets become ESTABLISHED.
 654         * 2) data_ready method of the child socket may be called
 655         *    when it receives data before the socket is accepted.
 656         * In case of 2, we should ignore it silently.
 657         */
 658        if (sk->sk_state == TCP_LISTEN) {
 659                if (svsk) {
 660                        set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 661                        svc_xprt_enqueue(&svsk->sk_xprt);
 662                } else
 663                        printk("svc: socket %p: no user data\n", sk);
 664        }
 665
 666        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 667                wake_up_interruptible_all(sk->sk_sleep);
 668}
 669
 670/*
 671 * A state change on a connected socket means it's dying or dead.
 672 */
 673static void svc_tcp_state_change(struct sock *sk)
 674{
 675        struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 676
 677        dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n",
 678                sk, sk->sk_state, sk->sk_user_data);
 679
 680        if (!svsk)
 681                printk("svc: socket %p: no user data\n", sk);
 682        else {
 683                set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 684                svc_xprt_enqueue(&svsk->sk_xprt);
 685        }
 686        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 687                wake_up_interruptible_all(sk->sk_sleep);
 688}
 689
 690static void svc_tcp_data_ready(struct sock *sk, int count)
 691{
 692        struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data;
 693
 694        dprintk("svc: socket %p TCP data ready (svsk %p)\n",
 695                sk, sk->sk_user_data);
 696        if (svsk) {
 697                set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 698                svc_xprt_enqueue(&svsk->sk_xprt);
 699        }
 700        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
 701                wake_up_interruptible(sk->sk_sleep);
 702}
 703
 704/*
 705 * Accept a TCP connection
 706 */
 707static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
 708{
 709        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 710        struct sockaddr_storage addr;
 711        struct sockaddr *sin = (struct sockaddr *) &addr;
 712        struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 713        struct socket   *sock = svsk->sk_sock;
 714        struct socket   *newsock;
 715        struct svc_sock *newsvsk;
 716        int             err, slen;
 717        RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 718
 719        dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
 720        if (!sock)
 721                return NULL;
 722
 723        clear_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 724        err = kernel_accept(sock, &newsock, O_NONBLOCK);
 725        if (err < 0) {
 726                if (err == -ENOMEM)
 727                        printk(KERN_WARNING "%s: no more sockets!\n",
 728                               serv->sv_name);
 729                else if (err != -EAGAIN && net_ratelimit())
 730                        printk(KERN_WARNING "%s: accept failed (err %d)!\n",
 731                                   serv->sv_name, -err);
 732                return NULL;
 733        }
 734        set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 735
 736        err = kernel_getpeername(newsock, sin, &slen);
 737        if (err < 0) {
 738                if (net_ratelimit())
 739                        printk(KERN_WARNING "%s: peername failed (err %d)!\n",
 740                                   serv->sv_name, -err);
 741                goto failed;            /* aborted connection or whatever */
 742        }
 743
 744        /* Ideally, we would want to reject connections from unauthorized
 745         * hosts here, but when we get encryption, the IP of the host won't
 746         * tell us anything.  For now just warn about unpriv connections.
 747         */
 748        if (!svc_port_is_privileged(sin)) {
 749                dprintk(KERN_WARNING
 750                        "%s: connect from unprivileged port: %s\n",
 751                        serv->sv_name,
 752                        __svc_print_addr(sin, buf, sizeof(buf)));
 753        }
 754        dprintk("%s: connect from %s\n", serv->sv_name,
 755                __svc_print_addr(sin, buf, sizeof(buf)));
 756
 757        /* make sure that a write doesn't block forever when
 758         * low on memory
 759         */
 760        newsock->sk->sk_sndtimeo = HZ*30;
 761
 762        if (!(newsvsk = svc_setup_socket(serv, newsock, &err,
 763                                 (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY))))
 764                goto failed;
 765        svc_xprt_set_remote(&newsvsk->sk_xprt, sin, slen);
 766        err = kernel_getsockname(newsock, sin, &slen);
 767        if (unlikely(err < 0)) {
 768                dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err);
 769                slen = offsetof(struct sockaddr, sa_data);
 770        }
 771        svc_xprt_set_local(&newsvsk->sk_xprt, sin, slen);
 772
 773        if (serv->sv_stats)
 774                serv->sv_stats->nettcpconn++;
 775
 776        return &newsvsk->sk_xprt;
 777
 778failed:
 779        sock_release(newsock);
 780        return NULL;
 781}
 782
 783/*
 784 * Receive data from a TCP socket.
 785 */
 786static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
 787{
 788        struct svc_sock *svsk =
 789                container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt);
 790        struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 791        int             len;
 792        struct kvec *vec;
 793        int pnum, vlen;
 794
 795        dprintk("svc: tcp_recv %p data %d conn %d close %d\n",
 796                svsk, test_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags),
 797                test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
 798                test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
 799
 800        if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
 801                /* sndbuf needs to have room for one request
 802                 * per thread, otherwise we can stall even when the
 803                 * network isn't a bottleneck.
 804                 *
 805                 * We count all threads rather than threads in a
 806                 * particular pool, which provides an upper bound
 807                 * on the number of threads which will access the socket.
 808                 *
 809                 * rcvbuf just needs to be able to hold a few requests.
 810                 * Normally they will be removed from the queue
 811                 * as soon a a complete request arrives.
 812                 */
 813                svc_sock_setbufsize(svsk->sk_sock,
 814                                    (serv->sv_nrthreads+3) * serv->sv_max_mesg,
 815                                    3 * serv->sv_max_mesg);
 816
 817        clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 818
 819        /* Receive data. If we haven't got the record length yet, get
 820         * the next four bytes. Otherwise try to gobble up as much as
 821         * possible up to the complete record length.
 822         */
 823        if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
 824                int             want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
 825                struct kvec     iov;
 826
 827                iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
 828                iov.iov_len  = want;
 829                if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0)
 830                        goto error;
 831                svsk->sk_tcplen += len;
 832
 833                if (len < want) {
 834                        dprintk("svc: short recvfrom while reading record "
 835                                "length (%d of %d)\n", len, want);
 836                        svc_xprt_received(&svsk->sk_xprt);
 837                        return -EAGAIN; /* record header not complete */
 838                }
 839
 840                svsk->sk_reclen = ntohl(svsk->sk_reclen);
 841                if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
 842                        /* FIXME: technically, a record can be fragmented,
 843                         *  and non-terminal fragments will not have the top
 844                         *  bit set in the fragment length header.
 845                         *  But apparently no known nfs clients send fragmented
 846                         *  records. */
 847                        if (net_ratelimit())
 848                                printk(KERN_NOTICE "RPC: multiple fragments "
 849                                        "per record not supported\n");
 850                        goto err_delete;
 851                }
 852                svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
 853                dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
 854                if (svsk->sk_reclen > serv->sv_max_mesg) {
 855                        if (net_ratelimit())
 856                                printk(KERN_NOTICE "RPC: "
 857                                        "fragment too large: 0x%08lx\n",
 858                                        (unsigned long)svsk->sk_reclen);
 859                        goto err_delete;
 860                }
 861        }
 862
 863        /* Check whether enough data is available */
 864        len = svc_recv_available(svsk);
 865        if (len < 0)
 866                goto error;
 867
 868        if (len < svsk->sk_reclen) {
 869                dprintk("svc: incomplete TCP record (%d of %d)\n",
 870                        len, svsk->sk_reclen);
 871                svc_xprt_received(&svsk->sk_xprt);
 872                return -EAGAIN; /* record not complete */
 873        }
 874        len = svsk->sk_reclen;
 875        set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 876
 877        vec = rqstp->rq_vec;
 878        vec[0] = rqstp->rq_arg.head[0];
 879        vlen = PAGE_SIZE;
 880        pnum = 1;
 881        while (vlen < len) {
 882                vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]);
 883                vec[pnum].iov_len = PAGE_SIZE;
 884                pnum++;
 885                vlen += PAGE_SIZE;
 886        }
 887        rqstp->rq_respages = &rqstp->rq_pages[pnum];
 888
 889        /* Now receive data */
 890        len = svc_recvfrom(rqstp, vec, pnum, len);
 891        if (len < 0)
 892                goto error;
 893
 894        dprintk("svc: TCP complete record (%d bytes)\n", len);
 895        rqstp->rq_arg.len = len;
 896        rqstp->rq_arg.page_base = 0;
 897        if (len <= rqstp->rq_arg.head[0].iov_len) {
 898                rqstp->rq_arg.head[0].iov_len = len;
 899                rqstp->rq_arg.page_len = 0;
 900        } else {
 901                rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len;
 902        }
 903
 904        rqstp->rq_xprt_ctxt   = NULL;
 905        rqstp->rq_prot        = IPPROTO_TCP;
 906
 907        /* Reset TCP read info */
 908        svsk->sk_reclen = 0;
 909        svsk->sk_tcplen = 0;
 910
 911        svc_xprt_copy_addrs(rqstp, &svsk->sk_xprt);
 912        svc_xprt_received(&svsk->sk_xprt);
 913        if (serv->sv_stats)
 914                serv->sv_stats->nettcpcnt++;
 915
 916        return len;
 917
 918 err_delete:
 919        set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
 920        return -EAGAIN;
 921
 922 error:
 923        if (len == -EAGAIN) {
 924                dprintk("RPC: TCP recvfrom got EAGAIN\n");
 925                svc_xprt_received(&svsk->sk_xprt);
 926        } else {
 927                printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
 928                       svsk->sk_xprt.xpt_server->sv_name, -len);
 929                goto err_delete;
 930        }
 931
 932        return len;
 933}
 934
 935/*
 936 * Send out data on TCP socket.
 937 */
 938static int svc_tcp_sendto(struct svc_rqst *rqstp)
 939{
 940        struct xdr_buf  *xbufp = &rqstp->rq_res;
 941        int sent;
 942        __be32 reclen;
 943
 944        /* Set up the first element of the reply kvec.
 945         * Any other kvecs that may be in use have been taken
 946         * care of by the server implementation itself.
 947         */
 948        reclen = htonl(0x80000000|((xbufp->len ) - 4));
 949        memcpy(xbufp->head[0].iov_base, &reclen, 4);
 950
 951        if (test_bit(XPT_DEAD, &rqstp->rq_xprt->xpt_flags))
 952                return -ENOTCONN;
 953
 954        sent = svc_sendto(rqstp, &rqstp->rq_res);
 955        if (sent != xbufp->len) {
 956                printk(KERN_NOTICE
 957                       "rpc-srv/tcp: %s: %s %d when sending %d bytes "
 958                       "- shutting down socket\n",
 959                       rqstp->rq_xprt->xpt_server->sv_name,
 960                       (sent<0)?"got error":"sent only",
 961                       sent, xbufp->len);
 962                set_bit(XPT_CLOSE, &rqstp->rq_xprt->xpt_flags);
 963                svc_xprt_enqueue(rqstp->rq_xprt);
 964                sent = -EAGAIN;
 965        }
 966        return sent;
 967}
 968
 969/*
 970 * Setup response header. TCP has a 4B record length field.
 971 */
 972static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
 973{
 974        struct kvec *resv = &rqstp->rq_res.head[0];
 975
 976        /* tcp needs a space for the record length... */
 977        svc_putnl(resv, 0);
 978}
 979
 980static int svc_tcp_has_wspace(struct svc_xprt *xprt)
 981{
 982        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
 983        struct svc_serv *serv = svsk->sk_xprt.xpt_server;
 984        int required;
 985        int wspace;
 986
 987        /*
 988         * Set the SOCK_NOSPACE flag before checking the available
 989         * sock space.
 990         */
 991        set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
 992        required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
 993        wspace = sk_stream_wspace(svsk->sk_sk);
 994
 995        if (wspace < sk_stream_min_wspace(svsk->sk_sk))
 996                return 0;
 997        if (required * 2 > wspace)
 998                return 0;
 999
1000        clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
1001        return 1;
1002}
1003
1004static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
1005                                       struct sockaddr *sa, int salen,
1006                                       int flags)
1007{
1008        return svc_create_socket(serv, IPPROTO_TCP, sa, salen, flags);
1009}
1010
1011static struct svc_xprt_ops svc_tcp_ops = {
1012        .xpo_create = svc_tcp_create,
1013        .xpo_recvfrom = svc_tcp_recvfrom,
1014        .xpo_sendto = svc_tcp_sendto,
1015        .xpo_release_rqst = svc_release_skb,
1016        .xpo_detach = svc_tcp_sock_detach,
1017        .xpo_free = svc_sock_free,
1018        .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr,
1019        .xpo_has_wspace = svc_tcp_has_wspace,
1020        .xpo_accept = svc_tcp_accept,
1021};
1022
1023static struct svc_xprt_class svc_tcp_class = {
1024        .xcl_name = "tcp",
1025        .xcl_owner = THIS_MODULE,
1026        .xcl_ops = &svc_tcp_ops,
1027        .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP,
1028};
1029
1030void svc_init_xprt_sock(void)
1031{
1032        svc_reg_xprt_class(&svc_tcp_class);
1033        svc_reg_xprt_class(&svc_udp_class);
1034}
1035
1036void svc_cleanup_xprt_sock(void)
1037{
1038        svc_unreg_xprt_class(&svc_tcp_class);
1039        svc_unreg_xprt_class(&svc_udp_class);
1040}
1041
1042static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
1043{
1044        struct sock     *sk = svsk->sk_sk;
1045
1046        svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt, serv);
1047        set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
1048        if (sk->sk_state == TCP_LISTEN) {
1049                dprintk("setting up TCP socket for listening\n");
1050                set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
1051                sk->sk_data_ready = svc_tcp_listen_data_ready;
1052                set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
1053        } else {
1054                dprintk("setting up TCP socket for reading\n");
1055                sk->sk_state_change = svc_tcp_state_change;
1056                sk->sk_data_ready = svc_tcp_data_ready;
1057                sk->sk_write_space = svc_write_space;
1058
1059                svsk->sk_reclen = 0;
1060                svsk->sk_tcplen = 0;
1061
1062                tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1063
1064                /* initialise setting must have enough space to
1065                 * receive and respond to one request.
1066                 * svc_tcp_recvfrom will re-adjust if necessary
1067                 */
1068                svc_sock_setbufsize(svsk->sk_sock,
1069                                    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
1070                                    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
1071
1072                set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1073                set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
1074                if (sk->sk_state != TCP_ESTABLISHED)
1075                        set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
1076        }
1077}
1078
1079void svc_sock_update_bufs(struct svc_serv *serv)
1080{
1081        /*
1082         * The number of server threads has changed. Update
1083         * rcvbuf and sndbuf accordingly on all sockets
1084         */
1085        struct list_head *le;
1086
1087        spin_lock_bh(&serv->sv_lock);
1088        list_for_each(le, &serv->sv_permsocks) {
1089                struct svc_sock *svsk =
1090                        list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1091                set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1092        }
1093        list_for_each(le, &serv->sv_tempsocks) {
1094                struct svc_sock *svsk =
1095                        list_entry(le, struct svc_sock, sk_xprt.xpt_list);
1096                set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
1097        }
1098        spin_unlock_bh(&serv->sv_lock);
1099}
1100EXPORT_SYMBOL_GPL(svc_sock_update_bufs);
1101
1102/*
1103 * Initialize socket for RPC use and create svc_sock struct
1104 * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF.
1105 */
1106static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
1107                                                struct socket *sock,
1108                                                int *errp, int flags)
1109{
1110        struct svc_sock *svsk;
1111        struct sock     *inet;
1112        int             pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
1113
1114        dprintk("svc: svc_setup_socket %p\n", sock);
1115        if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) {
1116                *errp = -ENOMEM;
1117                return NULL;
1118        }
1119
1120        inet = sock->sk;
1121
1122        /* Register socket with portmapper */
1123        if (*errp >= 0 && pmap_register)
1124                *errp = svc_register(serv, inet->sk_family, inet->sk_protocol,
1125                                     ntohs(inet_sk(inet)->sport));
1126
1127        if (*errp < 0) {
1128                kfree(svsk);
1129                return NULL;
1130        }
1131
1132        inet->sk_user_data = svsk;
1133        svsk->sk_sock = sock;
1134        svsk->sk_sk = inet;
1135        svsk->sk_ostate = inet->sk_state_change;
1136        svsk->sk_odata = inet->sk_data_ready;
1137        svsk->sk_owspace = inet->sk_write_space;
1138
1139        /* Initialize the socket */
1140        if (sock->type == SOCK_DGRAM)
1141                svc_udp_init(svsk, serv);
1142        else
1143                svc_tcp_init(svsk, serv);
1144
1145        dprintk("svc: svc_setup_socket created %p (inet %p)\n",
1146                                svsk, svsk->sk_sk);
1147
1148        return svsk;
1149}
1150
1151int svc_addsock(struct svc_serv *serv,
1152                int fd,
1153                char *name_return)
1154{
1155        int err = 0;
1156        struct socket *so = sockfd_lookup(fd, &err);
1157        struct svc_sock *svsk = NULL;
1158
1159        if (!so)
1160                return err;
1161        if (so->sk->sk_family != AF_INET)
1162                err =  -EAFNOSUPPORT;
1163        else if (so->sk->sk_protocol != IPPROTO_TCP &&
1164            so->sk->sk_protocol != IPPROTO_UDP)
1165                err =  -EPROTONOSUPPORT;
1166        else if (so->state > SS_UNCONNECTED)
1167                err = -EISCONN;
1168        else {
1169                if (!try_module_get(THIS_MODULE))
1170                        err = -ENOENT;
1171                else
1172                        svsk = svc_setup_socket(serv, so, &err,
1173                                                SVC_SOCK_DEFAULTS);
1174                if (svsk) {
1175                        struct sockaddr_storage addr;
1176                        struct sockaddr *sin = (struct sockaddr *)&addr;
1177                        int salen;
1178                        if (kernel_getsockname(svsk->sk_sock, sin, &salen) == 0)
1179                                svc_xprt_set_local(&svsk->sk_xprt, sin, salen);
1180                        clear_bit(XPT_TEMP, &svsk->sk_xprt.xpt_flags);
1181                        spin_lock_bh(&serv->sv_lock);
1182                        list_add(&svsk->sk_xprt.xpt_list, &serv->sv_permsocks);
1183                        spin_unlock_bh(&serv->sv_lock);
1184                        svc_xprt_received(&svsk->sk_xprt);
1185                        err = 0;
1186                } else
1187                        module_put(THIS_MODULE);
1188        }
1189        if (err) {
1190                sockfd_put(so);
1191                return err;
1192        }
1193        return one_sock_name(name_return, svsk);
1194}
1195EXPORT_SYMBOL_GPL(svc_addsock);
1196
1197/*
1198 * Create socket for RPC service.
1199 */
1200static struct svc_xprt *svc_create_socket(struct svc_serv *serv,
1201                                          int protocol,
1202                                          struct sockaddr *sin, int len,
1203                                          int flags)
1204{
1205        struct svc_sock *svsk;
1206        struct socket   *sock;
1207        int             error;
1208        int             type;
1209        struct sockaddr_storage addr;
1210        struct sockaddr *newsin = (struct sockaddr *)&addr;
1211        int             newlen;
1212        int             family;
1213        int             val;
1214        RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1215
1216        dprintk("svc: svc_create_socket(%s, %d, %s)\n",
1217                        serv->sv_program->pg_name, protocol,
1218                        __svc_print_addr(sin, buf, sizeof(buf)));
1219
1220        if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) {
1221                printk(KERN_WARNING "svc: only UDP and TCP "
1222                                "sockets supported\n");
1223                return ERR_PTR(-EINVAL);
1224        }
1225
1226        type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM;
1227        switch (sin->sa_family) {
1228        case AF_INET6:
1229                family = PF_INET6;
1230                break;
1231        case AF_INET:
1232                family = PF_INET;
1233                break;
1234        default:
1235                return ERR_PTR(-EINVAL);
1236        }
1237
1238        error = sock_create_kern(family, type, protocol, &sock);
1239        if (error < 0)
1240                return ERR_PTR(error);
1241
1242        svc_reclassify_socket(sock);
1243
1244        /*
1245         * If this is an PF_INET6 listener, we want to avoid
1246         * getting requests from IPv4 remotes.  Those should
1247         * be shunted to a PF_INET listener via rpcbind.
1248         */
1249        val = 1;
1250        if (family == PF_INET6)
1251                kernel_setsockopt(sock, SOL_IPV6, IPV6_V6ONLY,
1252                                        (char *)&val, sizeof(val));
1253
1254        if (type == SOCK_STREAM)
1255                sock->sk->sk_reuse = 1;         /* allow address reuse */
1256        error = kernel_bind(sock, sin, len);
1257        if (error < 0)
1258                goto bummer;
1259
1260        newlen = len;
1261        error = kernel_getsockname(sock, newsin, &newlen);
1262        if (error < 0)
1263                goto bummer;
1264
1265        if (protocol == IPPROTO_TCP) {
1266                if ((error = kernel_listen(sock, 64)) < 0)
1267                        goto bummer;
1268        }
1269
1270        if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) {
1271                svc_xprt_set_local(&svsk->sk_xprt, newsin, newlen);
1272                return (struct svc_xprt *)svsk;
1273        }
1274
1275bummer:
1276        dprintk("svc: svc_create_socket error = %d\n", -error);
1277        sock_release(sock);
1278        return ERR_PTR(error);
1279}
1280
1281/*
1282 * Detach the svc_sock from the socket so that no
1283 * more callbacks occur.
1284 */
1285static void svc_sock_detach(struct svc_xprt *xprt)
1286{
1287        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1288        struct sock *sk = svsk->sk_sk;
1289
1290        dprintk("svc: svc_sock_detach(%p)\n", svsk);
1291
1292        /* put back the old socket callbacks */
1293        sk->sk_state_change = svsk->sk_ostate;
1294        sk->sk_data_ready = svsk->sk_odata;
1295        sk->sk_write_space = svsk->sk_owspace;
1296
1297        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1298                wake_up_interruptible(sk->sk_sleep);
1299}
1300
1301/*
1302 * Disconnect the socket, and reset the callbacks
1303 */
1304static void svc_tcp_sock_detach(struct svc_xprt *xprt)
1305{
1306        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1307
1308        dprintk("svc: svc_tcp_sock_detach(%p)\n", svsk);
1309
1310        svc_sock_detach(xprt);
1311
1312        if (!test_bit(XPT_LISTENER, &xprt->xpt_flags))
1313                kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
1314}
1315
1316/*
1317 * Free the svc_sock's socket resources and the svc_sock itself.
1318 */
1319static void svc_sock_free(struct svc_xprt *xprt)
1320{
1321        struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
1322        dprintk("svc: svc_sock_free(%p)\n", svsk);
1323
1324        if (svsk->sk_sock->file)
1325                sockfd_put(svsk->sk_sock);
1326        else
1327                sock_release(svsk->sk_sock);
1328        kfree(svsk);
1329}
1330