linux/net/sunrpc/xprtsock.c
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   1/*
   2 * linux/net/sunrpc/xprtsock.c
   3 *
   4 * Client-side transport implementation for sockets.
   5 *
   6 * TCP callback races fixes (C) 1998 Red Hat
   7 * TCP send fixes (C) 1998 Red Hat
   8 * TCP NFS related read + write fixes
   9 *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  10 *
  11 * Rewrite of larges part of the code in order to stabilize TCP stuff.
  12 * Fix behaviour when socket buffer is full.
  13 *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  14 *
  15 * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  16 *
  17 * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  18 *   <gilles.quillard@bull.net>
  19 */
  20
  21#include <linux/types.h>
  22#include <linux/slab.h>
  23#include <linux/module.h>
  24#include <linux/capability.h>
  25#include <linux/pagemap.h>
  26#include <linux/errno.h>
  27#include <linux/socket.h>
  28#include <linux/in.h>
  29#include <linux/net.h>
  30#include <linux/mm.h>
  31#include <linux/udp.h>
  32#include <linux/tcp.h>
  33#include <linux/sunrpc/clnt.h>
  34#include <linux/sunrpc/sched.h>
  35#include <linux/sunrpc/svcsock.h>
  36#include <linux/sunrpc/xprtsock.h>
  37#include <linux/file.h>
  38#ifdef CONFIG_NFS_V4_1
  39#include <linux/sunrpc/bc_xprt.h>
  40#endif
  41
  42#include <net/sock.h>
  43#include <net/checksum.h>
  44#include <net/udp.h>
  45#include <net/tcp.h>
  46
  47#include "sunrpc.h"
  48/*
  49 * xprtsock tunables
  50 */
  51unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  52unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  53
  54unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  55unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  56
  57#define XS_TCP_LINGER_TO        (15U * HZ)
  58static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  59
  60/*
  61 * We can register our own files under /proc/sys/sunrpc by
  62 * calling register_sysctl_table() again.  The files in that
  63 * directory become the union of all files registered there.
  64 *
  65 * We simply need to make sure that we don't collide with
  66 * someone else's file names!
  67 */
  68
  69#ifdef RPC_DEBUG
  70
  71static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  72static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  73static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  74static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  75
  76static struct ctl_table_header *sunrpc_table_header;
  77
  78/*
  79 * FIXME: changing the UDP slot table size should also resize the UDP
  80 *        socket buffers for existing UDP transports
  81 */
  82static ctl_table xs_tunables_table[] = {
  83        {
  84                .procname       = "udp_slot_table_entries",
  85                .data           = &xprt_udp_slot_table_entries,
  86                .maxlen         = sizeof(unsigned int),
  87                .mode           = 0644,
  88                .proc_handler   = proc_dointvec_minmax,
  89                .extra1         = &min_slot_table_size,
  90                .extra2         = &max_slot_table_size
  91        },
  92        {
  93                .procname       = "tcp_slot_table_entries",
  94                .data           = &xprt_tcp_slot_table_entries,
  95                .maxlen         = sizeof(unsigned int),
  96                .mode           = 0644,
  97                .proc_handler   = proc_dointvec_minmax,
  98                .extra1         = &min_slot_table_size,
  99                .extra2         = &max_slot_table_size
 100        },
 101        {
 102                .procname       = "min_resvport",
 103                .data           = &xprt_min_resvport,
 104                .maxlen         = sizeof(unsigned int),
 105                .mode           = 0644,
 106                .proc_handler   = proc_dointvec_minmax,
 107                .extra1         = &xprt_min_resvport_limit,
 108                .extra2         = &xprt_max_resvport_limit
 109        },
 110        {
 111                .procname       = "max_resvport",
 112                .data           = &xprt_max_resvport,
 113                .maxlen         = sizeof(unsigned int),
 114                .mode           = 0644,
 115                .proc_handler   = proc_dointvec_minmax,
 116                .extra1         = &xprt_min_resvport_limit,
 117                .extra2         = &xprt_max_resvport_limit
 118        },
 119        {
 120                .procname       = "tcp_fin_timeout",
 121                .data           = &xs_tcp_fin_timeout,
 122                .maxlen         = sizeof(xs_tcp_fin_timeout),
 123                .mode           = 0644,
 124                .proc_handler   = proc_dointvec_jiffies,
 125        },
 126        { },
 127};
 128
 129static ctl_table sunrpc_table[] = {
 130        {
 131                .procname       = "sunrpc",
 132                .mode           = 0555,
 133                .child          = xs_tunables_table
 134        },
 135        { },
 136};
 137
 138#endif
 139
 140/*
 141 * Wait duration for a reply from the RPC portmapper.
 142 */
 143#define XS_BIND_TO              (60U * HZ)
 144
 145/*
 146 * Delay if a UDP socket connect error occurs.  This is most likely some
 147 * kind of resource problem on the local host.
 148 */
 149#define XS_UDP_REEST_TO         (2U * HZ)
 150
 151/*
 152 * The reestablish timeout allows clients to delay for a bit before attempting
 153 * to reconnect to a server that just dropped our connection.
 154 *
 155 * We implement an exponential backoff when trying to reestablish a TCP
 156 * transport connection with the server.  Some servers like to drop a TCP
 157 * connection when they are overworked, so we start with a short timeout and
 158 * increase over time if the server is down or not responding.
 159 */
 160#define XS_TCP_INIT_REEST_TO    (3U * HZ)
 161#define XS_TCP_MAX_REEST_TO     (5U * 60 * HZ)
 162
 163/*
 164 * TCP idle timeout; client drops the transport socket if it is idle
 165 * for this long.  Note that we also timeout UDP sockets to prevent
 166 * holding port numbers when there is no RPC traffic.
 167 */
 168#define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 169
 170#ifdef RPC_DEBUG
 171# undef  RPC_DEBUG_DATA
 172# define RPCDBG_FACILITY        RPCDBG_TRANS
 173#endif
 174
 175#ifdef RPC_DEBUG_DATA
 176static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 177{
 178        u8 *buf = (u8 *) packet;
 179        int j;
 180
 181        dprintk("RPC:       %s\n", msg);
 182        for (j = 0; j < count && j < 128; j += 4) {
 183                if (!(j & 31)) {
 184                        if (j)
 185                                dprintk("\n");
 186                        dprintk("0x%04x ", j);
 187                }
 188                dprintk("%02x%02x%02x%02x ",
 189                        buf[j], buf[j+1], buf[j+2], buf[j+3]);
 190        }
 191        dprintk("\n");
 192}
 193#else
 194static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 195{
 196        /* NOP */
 197}
 198#endif
 199
 200struct sock_xprt {
 201        struct rpc_xprt         xprt;
 202
 203        /*
 204         * Network layer
 205         */
 206        struct socket *         sock;
 207        struct sock *           inet;
 208
 209        /*
 210         * State of TCP reply receive
 211         */
 212        __be32                  tcp_fraghdr,
 213                                tcp_xid,
 214                                tcp_calldir;
 215
 216        u32                     tcp_offset,
 217                                tcp_reclen;
 218
 219        unsigned long           tcp_copied,
 220                                tcp_flags;
 221
 222        /*
 223         * Connection of transports
 224         */
 225        struct delayed_work     connect_worker;
 226        struct sockaddr_storage srcaddr;
 227        unsigned short          srcport;
 228
 229        /*
 230         * UDP socket buffer size parameters
 231         */
 232        size_t                  rcvsize,
 233                                sndsize;
 234
 235        /*
 236         * Saved socket callback addresses
 237         */
 238        void                    (*old_data_ready)(struct sock *, int);
 239        void                    (*old_state_change)(struct sock *);
 240        void                    (*old_write_space)(struct sock *);
 241        void                    (*old_error_report)(struct sock *);
 242};
 243
 244/*
 245 * TCP receive state flags
 246 */
 247#define TCP_RCV_LAST_FRAG       (1UL << 0)
 248#define TCP_RCV_COPY_FRAGHDR    (1UL << 1)
 249#define TCP_RCV_COPY_XID        (1UL << 2)
 250#define TCP_RCV_COPY_DATA       (1UL << 3)
 251#define TCP_RCV_READ_CALLDIR    (1UL << 4)
 252#define TCP_RCV_COPY_CALLDIR    (1UL << 5)
 253
 254/*
 255 * TCP RPC flags
 256 */
 257#define TCP_RPC_REPLY           (1UL << 6)
 258
 259static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 260{
 261        return (struct sockaddr *) &xprt->addr;
 262}
 263
 264static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 265{
 266        return (struct sockaddr_in *) &xprt->addr;
 267}
 268
 269static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 270{
 271        return (struct sockaddr_in6 *) &xprt->addr;
 272}
 273
 274static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 275{
 276        struct sockaddr *sap = xs_addr(xprt);
 277        struct sockaddr_in6 *sin6;
 278        struct sockaddr_in *sin;
 279        char buf[128];
 280
 281        (void)rpc_ntop(sap, buf, sizeof(buf));
 282        xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL);
 283
 284        switch (sap->sa_family) {
 285        case AF_INET:
 286                sin = xs_addr_in(xprt);
 287                snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 288                break;
 289        case AF_INET6:
 290                sin6 = xs_addr_in6(xprt);
 291                snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 292                break;
 293        default:
 294                BUG();
 295        }
 296        xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 297}
 298
 299static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 300{
 301        struct sockaddr *sap = xs_addr(xprt);
 302        char buf[128];
 303
 304        snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 305        xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 306
 307        snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 308        xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 309}
 310
 311static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 312                                     const char *protocol,
 313                                     const char *netid)
 314{
 315        xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 316        xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 317        xs_format_common_peer_addresses(xprt);
 318        xs_format_common_peer_ports(xprt);
 319}
 320
 321static void xs_update_peer_port(struct rpc_xprt *xprt)
 322{
 323        kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 324        kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 325
 326        xs_format_common_peer_ports(xprt);
 327}
 328
 329static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 330{
 331        unsigned int i;
 332
 333        for (i = 0; i < RPC_DISPLAY_MAX; i++)
 334                switch (i) {
 335                case RPC_DISPLAY_PROTO:
 336                case RPC_DISPLAY_NETID:
 337                        continue;
 338                default:
 339                        kfree(xprt->address_strings[i]);
 340                }
 341}
 342
 343#define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 344
 345static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 346{
 347        struct msghdr msg = {
 348                .msg_name       = addr,
 349                .msg_namelen    = addrlen,
 350                .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 351        };
 352        struct kvec iov = {
 353                .iov_base       = vec->iov_base + base,
 354                .iov_len        = vec->iov_len - base,
 355        };
 356
 357        if (iov.iov_len != 0)
 358                return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 359        return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 360}
 361
 362static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more)
 363{
 364        struct page **ppage;
 365        unsigned int remainder;
 366        int err, sent = 0;
 367
 368        remainder = xdr->page_len - base;
 369        base += xdr->page_base;
 370        ppage = xdr->pages + (base >> PAGE_SHIFT);
 371        base &= ~PAGE_MASK;
 372        for(;;) {
 373                unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 374                int flags = XS_SENDMSG_FLAGS;
 375
 376                remainder -= len;
 377                if (remainder != 0 || more)
 378                        flags |= MSG_MORE;
 379                err = sock->ops->sendpage(sock, *ppage, base, len, flags);
 380                if (remainder == 0 || err != len)
 381                        break;
 382                sent += err;
 383                ppage++;
 384                base = 0;
 385        }
 386        if (sent == 0)
 387                return err;
 388        if (err > 0)
 389                sent += err;
 390        return sent;
 391}
 392
 393/**
 394 * xs_sendpages - write pages directly to a socket
 395 * @sock: socket to send on
 396 * @addr: UDP only -- address of destination
 397 * @addrlen: UDP only -- length of destination address
 398 * @xdr: buffer containing this request
 399 * @base: starting position in the buffer
 400 *
 401 */
 402static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
 403{
 404        unsigned int remainder = xdr->len - base;
 405        int err, sent = 0;
 406
 407        if (unlikely(!sock))
 408                return -ENOTSOCK;
 409
 410        clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 411        if (base != 0) {
 412                addr = NULL;
 413                addrlen = 0;
 414        }
 415
 416        if (base < xdr->head[0].iov_len || addr != NULL) {
 417                unsigned int len = xdr->head[0].iov_len - base;
 418                remainder -= len;
 419                err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 420                if (remainder == 0 || err != len)
 421                        goto out;
 422                sent += err;
 423                base = 0;
 424        } else
 425                base -= xdr->head[0].iov_len;
 426
 427        if (base < xdr->page_len) {
 428                unsigned int len = xdr->page_len - base;
 429                remainder -= len;
 430                err = xs_send_pagedata(sock, xdr, base, remainder != 0);
 431                if (remainder == 0 || err != len)
 432                        goto out;
 433                sent += err;
 434                base = 0;
 435        } else
 436                base -= xdr->page_len;
 437
 438        if (base >= xdr->tail[0].iov_len)
 439                return sent;
 440        err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 441out:
 442        if (sent == 0)
 443                return err;
 444        if (err > 0)
 445                sent += err;
 446        return sent;
 447}
 448
 449static void xs_nospace_callback(struct rpc_task *task)
 450{
 451        struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 452
 453        transport->inet->sk_write_pending--;
 454        clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 455}
 456
 457/**
 458 * xs_nospace - place task on wait queue if transmit was incomplete
 459 * @task: task to put to sleep
 460 *
 461 */
 462static int xs_nospace(struct rpc_task *task)
 463{
 464        struct rpc_rqst *req = task->tk_rqstp;
 465        struct rpc_xprt *xprt = req->rq_xprt;
 466        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 467        int ret = 0;
 468
 469        dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 470                        task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 471                        req->rq_slen);
 472
 473        /* Protect against races with write_space */
 474        spin_lock_bh(&xprt->transport_lock);
 475
 476        /* Don't race with disconnect */
 477        if (xprt_connected(xprt)) {
 478                if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
 479                        ret = -EAGAIN;
 480                        /*
 481                         * Notify TCP that we're limited by the application
 482                         * window size
 483                         */
 484                        set_bit(SOCK_NOSPACE, &transport->sock->flags);
 485                        transport->inet->sk_write_pending++;
 486                        /* ...and wait for more buffer space */
 487                        xprt_wait_for_buffer_space(task, xs_nospace_callback);
 488                }
 489        } else {
 490                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 491                ret = -ENOTCONN;
 492        }
 493
 494        spin_unlock_bh(&xprt->transport_lock);
 495        return ret;
 496}
 497
 498/**
 499 * xs_udp_send_request - write an RPC request to a UDP socket
 500 * @task: address of RPC task that manages the state of an RPC request
 501 *
 502 * Return values:
 503 *        0:    The request has been sent
 504 *   EAGAIN:    The socket was blocked, please call again later to
 505 *              complete the request
 506 * ENOTCONN:    Caller needs to invoke connect logic then call again
 507 *    other:    Some other error occured, the request was not sent
 508 */
 509static int xs_udp_send_request(struct rpc_task *task)
 510{
 511        struct rpc_rqst *req = task->tk_rqstp;
 512        struct rpc_xprt *xprt = req->rq_xprt;
 513        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 514        struct xdr_buf *xdr = &req->rq_snd_buf;
 515        int status;
 516
 517        xs_pktdump("packet data:",
 518                                req->rq_svec->iov_base,
 519                                req->rq_svec->iov_len);
 520
 521        if (!xprt_bound(xprt))
 522                return -ENOTCONN;
 523        status = xs_sendpages(transport->sock,
 524                              xs_addr(xprt),
 525                              xprt->addrlen, xdr,
 526                              req->rq_bytes_sent);
 527
 528        dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 529                        xdr->len - req->rq_bytes_sent, status);
 530
 531        if (status >= 0) {
 532                req->rq_xmit_bytes_sent += status;
 533                if (status >= req->rq_slen)
 534                        return 0;
 535                /* Still some bytes left; set up for a retry later. */
 536                status = -EAGAIN;
 537        }
 538
 539        switch (status) {
 540        case -ENOTSOCK:
 541                status = -ENOTCONN;
 542                /* Should we call xs_close() here? */
 543                break;
 544        case -EAGAIN:
 545                status = xs_nospace(task);
 546                break;
 547        default:
 548                dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 549                        -status);
 550        case -ENETUNREACH:
 551        case -EPIPE:
 552        case -ECONNREFUSED:
 553                /* When the server has died, an ICMP port unreachable message
 554                 * prompts ECONNREFUSED. */
 555                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 556        }
 557
 558        return status;
 559}
 560
 561/**
 562 * xs_tcp_shutdown - gracefully shut down a TCP socket
 563 * @xprt: transport
 564 *
 565 * Initiates a graceful shutdown of the TCP socket by calling the
 566 * equivalent of shutdown(SHUT_WR);
 567 */
 568static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 569{
 570        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 571        struct socket *sock = transport->sock;
 572
 573        if (sock != NULL)
 574                kernel_sock_shutdown(sock, SHUT_WR);
 575}
 576
 577static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf)
 578{
 579        u32 reclen = buf->len - sizeof(rpc_fraghdr);
 580        rpc_fraghdr *base = buf->head[0].iov_base;
 581        *base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen);
 582}
 583
 584/**
 585 * xs_tcp_send_request - write an RPC request to a TCP socket
 586 * @task: address of RPC task that manages the state of an RPC request
 587 *
 588 * Return values:
 589 *        0:    The request has been sent
 590 *   EAGAIN:    The socket was blocked, please call again later to
 591 *              complete the request
 592 * ENOTCONN:    Caller needs to invoke connect logic then call again
 593 *    other:    Some other error occured, the request was not sent
 594 *
 595 * XXX: In the case of soft timeouts, should we eventually give up
 596 *      if sendmsg is not able to make progress?
 597 */
 598static int xs_tcp_send_request(struct rpc_task *task)
 599{
 600        struct rpc_rqst *req = task->tk_rqstp;
 601        struct rpc_xprt *xprt = req->rq_xprt;
 602        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 603        struct xdr_buf *xdr = &req->rq_snd_buf;
 604        int status;
 605
 606        xs_encode_tcp_record_marker(&req->rq_snd_buf);
 607
 608        xs_pktdump("packet data:",
 609                                req->rq_svec->iov_base,
 610                                req->rq_svec->iov_len);
 611
 612        /* Continue transmitting the packet/record. We must be careful
 613         * to cope with writespace callbacks arriving _after_ we have
 614         * called sendmsg(). */
 615        while (1) {
 616                status = xs_sendpages(transport->sock,
 617                                        NULL, 0, xdr, req->rq_bytes_sent);
 618
 619                dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 620                                xdr->len - req->rq_bytes_sent, status);
 621
 622                if (unlikely(status < 0))
 623                        break;
 624
 625                /* If we've sent the entire packet, immediately
 626                 * reset the count of bytes sent. */
 627                req->rq_bytes_sent += status;
 628                req->rq_xmit_bytes_sent += status;
 629                if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 630                        req->rq_bytes_sent = 0;
 631                        return 0;
 632                }
 633
 634                if (status != 0)
 635                        continue;
 636                status = -EAGAIN;
 637                break;
 638        }
 639
 640        switch (status) {
 641        case -ENOTSOCK:
 642                status = -ENOTCONN;
 643                /* Should we call xs_close() here? */
 644                break;
 645        case -EAGAIN:
 646                status = xs_nospace(task);
 647                break;
 648        default:
 649                dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 650                        -status);
 651        case -ECONNRESET:
 652        case -EPIPE:
 653                xs_tcp_shutdown(xprt);
 654        case -ECONNREFUSED:
 655        case -ENOTCONN:
 656                clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 657        }
 658
 659        return status;
 660}
 661
 662/**
 663 * xs_tcp_release_xprt - clean up after a tcp transmission
 664 * @xprt: transport
 665 * @task: rpc task
 666 *
 667 * This cleans up if an error causes us to abort the transmission of a request.
 668 * In this case, the socket may need to be reset in order to avoid confusing
 669 * the server.
 670 */
 671static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 672{
 673        struct rpc_rqst *req;
 674
 675        if (task != xprt->snd_task)
 676                return;
 677        if (task == NULL)
 678                goto out_release;
 679        req = task->tk_rqstp;
 680        if (req->rq_bytes_sent == 0)
 681                goto out_release;
 682        if (req->rq_bytes_sent == req->rq_snd_buf.len)
 683                goto out_release;
 684        set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
 685out_release:
 686        xprt_release_xprt(xprt, task);
 687}
 688
 689static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 690{
 691        transport->old_data_ready = sk->sk_data_ready;
 692        transport->old_state_change = sk->sk_state_change;
 693        transport->old_write_space = sk->sk_write_space;
 694        transport->old_error_report = sk->sk_error_report;
 695}
 696
 697static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 698{
 699        sk->sk_data_ready = transport->old_data_ready;
 700        sk->sk_state_change = transport->old_state_change;
 701        sk->sk_write_space = transport->old_write_space;
 702        sk->sk_error_report = transport->old_error_report;
 703}
 704
 705static void xs_reset_transport(struct sock_xprt *transport)
 706{
 707        struct socket *sock = transport->sock;
 708        struct sock *sk = transport->inet;
 709
 710        if (sk == NULL)
 711                return;
 712
 713        write_lock_bh(&sk->sk_callback_lock);
 714        transport->inet = NULL;
 715        transport->sock = NULL;
 716
 717        sk->sk_user_data = NULL;
 718
 719        xs_restore_old_callbacks(transport, sk);
 720        write_unlock_bh(&sk->sk_callback_lock);
 721
 722        sk->sk_no_check = 0;
 723
 724        sock_release(sock);
 725}
 726
 727/**
 728 * xs_close - close a socket
 729 * @xprt: transport
 730 *
 731 * This is used when all requests are complete; ie, no DRC state remains
 732 * on the server we want to save.
 733 *
 734 * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 735 * xs_reset_transport() zeroing the socket from underneath a writer.
 736 */
 737static void xs_close(struct rpc_xprt *xprt)
 738{
 739        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 740
 741        dprintk("RPC:       xs_close xprt %p\n", xprt);
 742
 743        xs_reset_transport(transport);
 744        xprt->reestablish_timeout = 0;
 745
 746        smp_mb__before_clear_bit();
 747        clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 748        clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 749        clear_bit(XPRT_CLOSING, &xprt->state);
 750        smp_mb__after_clear_bit();
 751        xprt_disconnect_done(xprt);
 752}
 753
 754static void xs_tcp_close(struct rpc_xprt *xprt)
 755{
 756        if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 757                xs_close(xprt);
 758        else
 759                xs_tcp_shutdown(xprt);
 760}
 761
 762/**
 763 * xs_destroy - prepare to shutdown a transport
 764 * @xprt: doomed transport
 765 *
 766 */
 767static void xs_destroy(struct rpc_xprt *xprt)
 768{
 769        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 770
 771        dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 772
 773        cancel_rearming_delayed_work(&transport->connect_worker);
 774
 775        xs_close(xprt);
 776        xs_free_peer_addresses(xprt);
 777        xprt_free(xprt);
 778        module_put(THIS_MODULE);
 779}
 780
 781static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 782{
 783        return (struct rpc_xprt *) sk->sk_user_data;
 784}
 785
 786/**
 787 * xs_udp_data_ready - "data ready" callback for UDP sockets
 788 * @sk: socket with data to read
 789 * @len: how much data to read
 790 *
 791 */
 792static void xs_udp_data_ready(struct sock *sk, int len)
 793{
 794        struct rpc_task *task;
 795        struct rpc_xprt *xprt;
 796        struct rpc_rqst *rovr;
 797        struct sk_buff *skb;
 798        int err, repsize, copied;
 799        u32 _xid;
 800        __be32 *xp;
 801
 802        read_lock_bh(&sk->sk_callback_lock);
 803        dprintk("RPC:       xs_udp_data_ready...\n");
 804        if (!(xprt = xprt_from_sock(sk)))
 805                goto out;
 806
 807        if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 808                goto out;
 809
 810        if (xprt->shutdown)
 811                goto dropit;
 812
 813        repsize = skb->len - sizeof(struct udphdr);
 814        if (repsize < 4) {
 815                dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
 816                goto dropit;
 817        }
 818
 819        /* Copy the XID from the skb... */
 820        xp = skb_header_pointer(skb, sizeof(struct udphdr),
 821                                sizeof(_xid), &_xid);
 822        if (xp == NULL)
 823                goto dropit;
 824
 825        /* Look up and lock the request corresponding to the given XID */
 826        spin_lock(&xprt->transport_lock);
 827        rovr = xprt_lookup_rqst(xprt, *xp);
 828        if (!rovr)
 829                goto out_unlock;
 830        task = rovr->rq_task;
 831
 832        if ((copied = rovr->rq_private_buf.buflen) > repsize)
 833                copied = repsize;
 834
 835        /* Suck it into the iovec, verify checksum if not done by hw. */
 836        if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 837                UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
 838                goto out_unlock;
 839        }
 840
 841        UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
 842
 843        /* Something worked... */
 844        dst_confirm(skb_dst(skb));
 845
 846        xprt_adjust_cwnd(task, copied);
 847        xprt_complete_rqst(task, copied);
 848
 849 out_unlock:
 850        spin_unlock(&xprt->transport_lock);
 851 dropit:
 852        skb_free_datagram(sk, skb);
 853 out:
 854        read_unlock_bh(&sk->sk_callback_lock);
 855}
 856
 857static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
 858{
 859        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 860        size_t len, used;
 861        char *p;
 862
 863        p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
 864        len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
 865        used = xdr_skb_read_bits(desc, p, len);
 866        transport->tcp_offset += used;
 867        if (used != len)
 868                return;
 869
 870        transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
 871        if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
 872                transport->tcp_flags |= TCP_RCV_LAST_FRAG;
 873        else
 874                transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
 875        transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
 876
 877        transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
 878        transport->tcp_offset = 0;
 879
 880        /* Sanity check of the record length */
 881        if (unlikely(transport->tcp_reclen < 8)) {
 882                dprintk("RPC:       invalid TCP record fragment length\n");
 883                xprt_force_disconnect(xprt);
 884                return;
 885        }
 886        dprintk("RPC:       reading TCP record fragment of length %d\n",
 887                        transport->tcp_reclen);
 888}
 889
 890static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
 891{
 892        if (transport->tcp_offset == transport->tcp_reclen) {
 893                transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
 894                transport->tcp_offset = 0;
 895                if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
 896                        transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
 897                        transport->tcp_flags |= TCP_RCV_COPY_XID;
 898                        transport->tcp_copied = 0;
 899                }
 900        }
 901}
 902
 903static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
 904{
 905        size_t len, used;
 906        char *p;
 907
 908        len = sizeof(transport->tcp_xid) - transport->tcp_offset;
 909        dprintk("RPC:       reading XID (%Zu bytes)\n", len);
 910        p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
 911        used = xdr_skb_read_bits(desc, p, len);
 912        transport->tcp_offset += used;
 913        if (used != len)
 914                return;
 915        transport->tcp_flags &= ~TCP_RCV_COPY_XID;
 916        transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
 917        transport->tcp_copied = 4;
 918        dprintk("RPC:       reading %s XID %08x\n",
 919                        (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
 920                                                              : "request with",
 921                        ntohl(transport->tcp_xid));
 922        xs_tcp_check_fraghdr(transport);
 923}
 924
 925static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
 926                                       struct xdr_skb_reader *desc)
 927{
 928        size_t len, used;
 929        u32 offset;
 930        char *p;
 931
 932        /*
 933         * We want transport->tcp_offset to be 8 at the end of this routine
 934         * (4 bytes for the xid and 4 bytes for the call/reply flag).
 935         * When this function is called for the first time,
 936         * transport->tcp_offset is 4 (after having already read the xid).
 937         */
 938        offset = transport->tcp_offset - sizeof(transport->tcp_xid);
 939        len = sizeof(transport->tcp_calldir) - offset;
 940        dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
 941        p = ((char *) &transport->tcp_calldir) + offset;
 942        used = xdr_skb_read_bits(desc, p, len);
 943        transport->tcp_offset += used;
 944        if (used != len)
 945                return;
 946        transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
 947        /*
 948         * We don't yet have the XDR buffer, so we will write the calldir
 949         * out after we get the buffer from the 'struct rpc_rqst'
 950         */
 951        switch (ntohl(transport->tcp_calldir)) {
 952        case RPC_REPLY:
 953                transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
 954                transport->tcp_flags |= TCP_RCV_COPY_DATA;
 955                transport->tcp_flags |= TCP_RPC_REPLY;
 956                break;
 957        case RPC_CALL:
 958                transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
 959                transport->tcp_flags |= TCP_RCV_COPY_DATA;
 960                transport->tcp_flags &= ~TCP_RPC_REPLY;
 961                break;
 962        default:
 963                dprintk("RPC:       invalid request message type\n");
 964                xprt_force_disconnect(&transport->xprt);
 965        }
 966        xs_tcp_check_fraghdr(transport);
 967}
 968
 969static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
 970                                     struct xdr_skb_reader *desc,
 971                                     struct rpc_rqst *req)
 972{
 973        struct sock_xprt *transport =
 974                                container_of(xprt, struct sock_xprt, xprt);
 975        struct xdr_buf *rcvbuf;
 976        size_t len;
 977        ssize_t r;
 978
 979        rcvbuf = &req->rq_private_buf;
 980
 981        if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
 982                /*
 983                 * Save the RPC direction in the XDR buffer
 984                 */
 985                memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
 986                        &transport->tcp_calldir,
 987                        sizeof(transport->tcp_calldir));
 988                transport->tcp_copied += sizeof(transport->tcp_calldir);
 989                transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
 990        }
 991
 992        len = desc->count;
 993        if (len > transport->tcp_reclen - transport->tcp_offset) {
 994                struct xdr_skb_reader my_desc;
 995
 996                len = transport->tcp_reclen - transport->tcp_offset;
 997                memcpy(&my_desc, desc, sizeof(my_desc));
 998                my_desc.count = len;
 999                r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1000                                          &my_desc, xdr_skb_read_bits);
1001                desc->count -= r;
1002                desc->offset += r;
1003        } else
1004                r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1005                                          desc, xdr_skb_read_bits);
1006
1007        if (r > 0) {
1008                transport->tcp_copied += r;
1009                transport->tcp_offset += r;
1010        }
1011        if (r != len) {
1012                /* Error when copying to the receive buffer,
1013                 * usually because we weren't able to allocate
1014                 * additional buffer pages. All we can do now
1015                 * is turn off TCP_RCV_COPY_DATA, so the request
1016                 * will not receive any additional updates,
1017                 * and time out.
1018                 * Any remaining data from this record will
1019                 * be discarded.
1020                 */
1021                transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1022                dprintk("RPC:       XID %08x truncated request\n",
1023                                ntohl(transport->tcp_xid));
1024                dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1025                                "tcp_offset = %u, tcp_reclen = %u\n",
1026                                xprt, transport->tcp_copied,
1027                                transport->tcp_offset, transport->tcp_reclen);
1028                return;
1029        }
1030
1031        dprintk("RPC:       XID %08x read %Zd bytes\n",
1032                        ntohl(transport->tcp_xid), r);
1033        dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1034                        "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1035                        transport->tcp_offset, transport->tcp_reclen);
1036
1037        if (transport->tcp_copied == req->rq_private_buf.buflen)
1038                transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1039        else if (transport->tcp_offset == transport->tcp_reclen) {
1040                if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1041                        transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1042        }
1043}
1044
1045/*
1046 * Finds the request corresponding to the RPC xid and invokes the common
1047 * tcp read code to read the data.
1048 */
1049static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1050                                    struct xdr_skb_reader *desc)
1051{
1052        struct sock_xprt *transport =
1053                                container_of(xprt, struct sock_xprt, xprt);
1054        struct rpc_rqst *req;
1055
1056        dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1057
1058        /* Find and lock the request corresponding to this xid */
1059        spin_lock(&xprt->transport_lock);
1060        req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1061        if (!req) {
1062                dprintk("RPC:       XID %08x request not found!\n",
1063                                ntohl(transport->tcp_xid));
1064                spin_unlock(&xprt->transport_lock);
1065                return -1;
1066        }
1067
1068        xs_tcp_read_common(xprt, desc, req);
1069
1070        if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1071                xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1072
1073        spin_unlock(&xprt->transport_lock);
1074        return 0;
1075}
1076
1077#if defined(CONFIG_NFS_V4_1)
1078/*
1079 * Obtains an rpc_rqst previously allocated and invokes the common
1080 * tcp read code to read the data.  The result is placed in the callback
1081 * queue.
1082 * If we're unable to obtain the rpc_rqst we schedule the closing of the
1083 * connection and return -1.
1084 */
1085static inline int xs_tcp_read_callback(struct rpc_xprt *xprt,
1086                                       struct xdr_skb_reader *desc)
1087{
1088        struct sock_xprt *transport =
1089                                container_of(xprt, struct sock_xprt, xprt);
1090        struct rpc_rqst *req;
1091
1092        req = xprt_alloc_bc_request(xprt);
1093        if (req == NULL) {
1094                printk(KERN_WARNING "Callback slot table overflowed\n");
1095                xprt_force_disconnect(xprt);
1096                return -1;
1097        }
1098
1099        req->rq_xid = transport->tcp_xid;
1100        dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1101        xs_tcp_read_common(xprt, desc, req);
1102
1103        if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) {
1104                struct svc_serv *bc_serv = xprt->bc_serv;
1105
1106                /*
1107                 * Add callback request to callback list.  The callback
1108                 * service sleeps on the sv_cb_waitq waiting for new
1109                 * requests.  Wake it up after adding enqueing the
1110                 * request.
1111                 */
1112                dprintk("RPC:       add callback request to list\n");
1113                spin_lock(&bc_serv->sv_cb_lock);
1114                list_add(&req->rq_bc_list, &bc_serv->sv_cb_list);
1115                spin_unlock(&bc_serv->sv_cb_lock);
1116                wake_up(&bc_serv->sv_cb_waitq);
1117        }
1118
1119        req->rq_private_buf.len = transport->tcp_copied;
1120
1121        return 0;
1122}
1123
1124static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1125                                        struct xdr_skb_reader *desc)
1126{
1127        struct sock_xprt *transport =
1128                                container_of(xprt, struct sock_xprt, xprt);
1129
1130        return (transport->tcp_flags & TCP_RPC_REPLY) ?
1131                xs_tcp_read_reply(xprt, desc) :
1132                xs_tcp_read_callback(xprt, desc);
1133}
1134#else
1135static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1136                                        struct xdr_skb_reader *desc)
1137{
1138        return xs_tcp_read_reply(xprt, desc);
1139}
1140#endif /* CONFIG_NFS_V4_1 */
1141
1142/*
1143 * Read data off the transport.  This can be either an RPC_CALL or an
1144 * RPC_REPLY.  Relay the processing to helper functions.
1145 */
1146static void xs_tcp_read_data(struct rpc_xprt *xprt,
1147                                    struct xdr_skb_reader *desc)
1148{
1149        struct sock_xprt *transport =
1150                                container_of(xprt, struct sock_xprt, xprt);
1151
1152        if (_xs_tcp_read_data(xprt, desc) == 0)
1153                xs_tcp_check_fraghdr(transport);
1154        else {
1155                /*
1156                 * The transport_lock protects the request handling.
1157                 * There's no need to hold it to update the tcp_flags.
1158                 */
1159                transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1160        }
1161}
1162
1163static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1164{
1165        size_t len;
1166
1167        len = transport->tcp_reclen - transport->tcp_offset;
1168        if (len > desc->count)
1169                len = desc->count;
1170        desc->count -= len;
1171        desc->offset += len;
1172        transport->tcp_offset += len;
1173        dprintk("RPC:       discarded %Zu bytes\n", len);
1174        xs_tcp_check_fraghdr(transport);
1175}
1176
1177static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1178{
1179        struct rpc_xprt *xprt = rd_desc->arg.data;
1180        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1181        struct xdr_skb_reader desc = {
1182                .skb    = skb,
1183                .offset = offset,
1184                .count  = len,
1185        };
1186
1187        dprintk("RPC:       xs_tcp_data_recv started\n");
1188        do {
1189                /* Read in a new fragment marker if necessary */
1190                /* Can we ever really expect to get completely empty fragments? */
1191                if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1192                        xs_tcp_read_fraghdr(xprt, &desc);
1193                        continue;
1194                }
1195                /* Read in the xid if necessary */
1196                if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1197                        xs_tcp_read_xid(transport, &desc);
1198                        continue;
1199                }
1200                /* Read in the call/reply flag */
1201                if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1202                        xs_tcp_read_calldir(transport, &desc);
1203                        continue;
1204                }
1205                /* Read in the request data */
1206                if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1207                        xs_tcp_read_data(xprt, &desc);
1208                        continue;
1209                }
1210                /* Skip over any trailing bytes on short reads */
1211                xs_tcp_read_discard(transport, &desc);
1212        } while (desc.count);
1213        dprintk("RPC:       xs_tcp_data_recv done\n");
1214        return len - desc.count;
1215}
1216
1217/**
1218 * xs_tcp_data_ready - "data ready" callback for TCP sockets
1219 * @sk: socket with data to read
1220 * @bytes: how much data to read
1221 *
1222 */
1223static void xs_tcp_data_ready(struct sock *sk, int bytes)
1224{
1225        struct rpc_xprt *xprt;
1226        read_descriptor_t rd_desc;
1227        int read;
1228
1229        dprintk("RPC:       xs_tcp_data_ready...\n");
1230
1231        read_lock_bh(&sk->sk_callback_lock);
1232        if (!(xprt = xprt_from_sock(sk)))
1233                goto out;
1234        if (xprt->shutdown)
1235                goto out;
1236
1237        /* Any data means we had a useful conversation, so
1238         * the we don't need to delay the next reconnect
1239         */
1240        if (xprt->reestablish_timeout)
1241                xprt->reestablish_timeout = 0;
1242
1243        /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1244        rd_desc.arg.data = xprt;
1245        do {
1246                rd_desc.count = 65536;
1247                read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1248        } while (read > 0);
1249out:
1250        read_unlock_bh(&sk->sk_callback_lock);
1251}
1252
1253/*
1254 * Do the equivalent of linger/linger2 handling for dealing with
1255 * broken servers that don't close the socket in a timely
1256 * fashion
1257 */
1258static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1259                unsigned long timeout)
1260{
1261        struct sock_xprt *transport;
1262
1263        if (xprt_test_and_set_connecting(xprt))
1264                return;
1265        set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1266        transport = container_of(xprt, struct sock_xprt, xprt);
1267        queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1268                           timeout);
1269}
1270
1271static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1272{
1273        struct sock_xprt *transport;
1274
1275        transport = container_of(xprt, struct sock_xprt, xprt);
1276
1277        if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1278            !cancel_delayed_work(&transport->connect_worker))
1279                return;
1280        clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1281        xprt_clear_connecting(xprt);
1282}
1283
1284static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1285{
1286        smp_mb__before_clear_bit();
1287        clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1288        clear_bit(XPRT_CLOSING, &xprt->state);
1289        smp_mb__after_clear_bit();
1290        /* Mark transport as closed and wake up all pending tasks */
1291        xprt_disconnect_done(xprt);
1292}
1293
1294/**
1295 * xs_tcp_state_change - callback to handle TCP socket state changes
1296 * @sk: socket whose state has changed
1297 *
1298 */
1299static void xs_tcp_state_change(struct sock *sk)
1300{
1301        struct rpc_xprt *xprt;
1302
1303        read_lock_bh(&sk->sk_callback_lock);
1304        if (!(xprt = xprt_from_sock(sk)))
1305                goto out;
1306        dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1307        dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1308                        sk->sk_state, xprt_connected(xprt),
1309                        sock_flag(sk, SOCK_DEAD),
1310                        sock_flag(sk, SOCK_ZAPPED),
1311                        sk->sk_shutdown);
1312
1313        switch (sk->sk_state) {
1314        case TCP_ESTABLISHED:
1315                spin_lock(&xprt->transport_lock);
1316                if (!xprt_test_and_set_connected(xprt)) {
1317                        struct sock_xprt *transport = container_of(xprt,
1318                                        struct sock_xprt, xprt);
1319
1320                        /* Reset TCP record info */
1321                        transport->tcp_offset = 0;
1322                        transport->tcp_reclen = 0;
1323                        transport->tcp_copied = 0;
1324                        transport->tcp_flags =
1325                                TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1326
1327                        xprt_wake_pending_tasks(xprt, -EAGAIN);
1328                }
1329                spin_unlock(&xprt->transport_lock);
1330                break;
1331        case TCP_FIN_WAIT1:
1332                /* The client initiated a shutdown of the socket */
1333                xprt->connect_cookie++;
1334                xprt->reestablish_timeout = 0;
1335                set_bit(XPRT_CLOSING, &xprt->state);
1336                smp_mb__before_clear_bit();
1337                clear_bit(XPRT_CONNECTED, &xprt->state);
1338                clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1339                smp_mb__after_clear_bit();
1340                xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1341                break;
1342        case TCP_CLOSE_WAIT:
1343                /* The server initiated a shutdown of the socket */
1344                xprt_force_disconnect(xprt);
1345        case TCP_SYN_SENT:
1346                xprt->connect_cookie++;
1347        case TCP_CLOSING:
1348                /*
1349                 * If the server closed down the connection, make sure that
1350                 * we back off before reconnecting
1351                 */
1352                if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1353                        xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1354                break;
1355        case TCP_LAST_ACK:
1356                set_bit(XPRT_CLOSING, &xprt->state);
1357                xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1358                smp_mb__before_clear_bit();
1359                clear_bit(XPRT_CONNECTED, &xprt->state);
1360                smp_mb__after_clear_bit();
1361                break;
1362        case TCP_CLOSE:
1363                xs_tcp_cancel_linger_timeout(xprt);
1364                xs_sock_mark_closed(xprt);
1365        }
1366 out:
1367        read_unlock_bh(&sk->sk_callback_lock);
1368}
1369
1370/**
1371 * xs_error_report - callback mainly for catching socket errors
1372 * @sk: socket
1373 */
1374static void xs_error_report(struct sock *sk)
1375{
1376        struct rpc_xprt *xprt;
1377
1378        read_lock_bh(&sk->sk_callback_lock);
1379        if (!(xprt = xprt_from_sock(sk)))
1380                goto out;
1381        dprintk("RPC:       %s client %p...\n"
1382                        "RPC:       error %d\n",
1383                        __func__, xprt, sk->sk_err);
1384        xprt_wake_pending_tasks(xprt, -EAGAIN);
1385out:
1386        read_unlock_bh(&sk->sk_callback_lock);
1387}
1388
1389static void xs_write_space(struct sock *sk)
1390{
1391        struct socket *sock;
1392        struct rpc_xprt *xprt;
1393
1394        if (unlikely(!(sock = sk->sk_socket)))
1395                return;
1396        clear_bit(SOCK_NOSPACE, &sock->flags);
1397
1398        if (unlikely(!(xprt = xprt_from_sock(sk))))
1399                return;
1400        if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1401                return;
1402
1403        xprt_write_space(xprt);
1404}
1405
1406/**
1407 * xs_udp_write_space - callback invoked when socket buffer space
1408 *                             becomes available
1409 * @sk: socket whose state has changed
1410 *
1411 * Called when more output buffer space is available for this socket.
1412 * We try not to wake our writers until they can make "significant"
1413 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1414 * with a bunch of small requests.
1415 */
1416static void xs_udp_write_space(struct sock *sk)
1417{
1418        read_lock_bh(&sk->sk_callback_lock);
1419
1420        /* from net/core/sock.c:sock_def_write_space */
1421        if (sock_writeable(sk))
1422                xs_write_space(sk);
1423
1424        read_unlock_bh(&sk->sk_callback_lock);
1425}
1426
1427/**
1428 * xs_tcp_write_space - callback invoked when socket buffer space
1429 *                             becomes available
1430 * @sk: socket whose state has changed
1431 *
1432 * Called when more output buffer space is available for this socket.
1433 * We try not to wake our writers until they can make "significant"
1434 * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1435 * with a bunch of small requests.
1436 */
1437static void xs_tcp_write_space(struct sock *sk)
1438{
1439        read_lock_bh(&sk->sk_callback_lock);
1440
1441        /* from net/core/stream.c:sk_stream_write_space */
1442        if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
1443                xs_write_space(sk);
1444
1445        read_unlock_bh(&sk->sk_callback_lock);
1446}
1447
1448static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1449{
1450        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1451        struct sock *sk = transport->inet;
1452
1453        if (transport->rcvsize) {
1454                sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1455                sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1456        }
1457        if (transport->sndsize) {
1458                sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1459                sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1460                sk->sk_write_space(sk);
1461        }
1462}
1463
1464/**
1465 * xs_udp_set_buffer_size - set send and receive limits
1466 * @xprt: generic transport
1467 * @sndsize: requested size of send buffer, in bytes
1468 * @rcvsize: requested size of receive buffer, in bytes
1469 *
1470 * Set socket send and receive buffer size limits.
1471 */
1472static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1473{
1474        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1475
1476        transport->sndsize = 0;
1477        if (sndsize)
1478                transport->sndsize = sndsize + 1024;
1479        transport->rcvsize = 0;
1480        if (rcvsize)
1481                transport->rcvsize = rcvsize + 1024;
1482
1483        xs_udp_do_set_buffer_size(xprt);
1484}
1485
1486/**
1487 * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1488 * @task: task that timed out
1489 *
1490 * Adjust the congestion window after a retransmit timeout has occurred.
1491 */
1492static void xs_udp_timer(struct rpc_task *task)
1493{
1494        xprt_adjust_cwnd(task, -ETIMEDOUT);
1495}
1496
1497static unsigned short xs_get_random_port(void)
1498{
1499        unsigned short range = xprt_max_resvport - xprt_min_resvport;
1500        unsigned short rand = (unsigned short) net_random() % range;
1501        return rand + xprt_min_resvport;
1502}
1503
1504/**
1505 * xs_set_port - reset the port number in the remote endpoint address
1506 * @xprt: generic transport
1507 * @port: new port number
1508 *
1509 */
1510static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1511{
1512        dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1513
1514        rpc_set_port(xs_addr(xprt), port);
1515        xs_update_peer_port(xprt);
1516}
1517
1518static unsigned short xs_get_srcport(struct sock_xprt *transport)
1519{
1520        unsigned short port = transport->srcport;
1521
1522        if (port == 0 && transport->xprt.resvport)
1523                port = xs_get_random_port();
1524        return port;
1525}
1526
1527static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1528{
1529        if (transport->srcport != 0)
1530                transport->srcport = 0;
1531        if (!transport->xprt.resvport)
1532                return 0;
1533        if (port <= xprt_min_resvport || port > xprt_max_resvport)
1534                return xprt_max_resvport;
1535        return --port;
1536}
1537static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1538{
1539        struct sockaddr_storage myaddr;
1540        int err, nloop = 0;
1541        unsigned short port = xs_get_srcport(transport);
1542        unsigned short last;
1543
1544        memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1545        do {
1546                rpc_set_port((struct sockaddr *)&myaddr, port);
1547                err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1548                                transport->xprt.addrlen);
1549                if (port == 0)
1550                        break;
1551                if (err == 0) {
1552                        transport->srcport = port;
1553                        break;
1554                }
1555                last = port;
1556                port = xs_next_srcport(transport, port);
1557                if (port > last)
1558                        nloop++;
1559        } while (err == -EADDRINUSE && nloop != 2);
1560
1561        if (myaddr.ss_family == AF_INET)
1562                dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1563                                &((struct sockaddr_in *)&myaddr)->sin_addr,
1564                                port, err ? "failed" : "ok", err);
1565        else
1566                dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1567                                &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1568                                port, err ? "failed" : "ok", err);
1569        return err;
1570}
1571
1572
1573#ifdef CONFIG_DEBUG_LOCK_ALLOC
1574static struct lock_class_key xs_key[2];
1575static struct lock_class_key xs_slock_key[2];
1576
1577static inline void xs_reclassify_socket4(struct socket *sock)
1578{
1579        struct sock *sk = sock->sk;
1580
1581        BUG_ON(sock_owned_by_user(sk));
1582        sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1583                &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1584}
1585
1586static inline void xs_reclassify_socket6(struct socket *sock)
1587{
1588        struct sock *sk = sock->sk;
1589
1590        BUG_ON(sock_owned_by_user(sk));
1591        sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1592                &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1593}
1594
1595static inline void xs_reclassify_socket(int family, struct socket *sock)
1596{
1597        switch (family) {
1598        case AF_INET:
1599                xs_reclassify_socket4(sock);
1600                break;
1601        case AF_INET6:
1602                xs_reclassify_socket6(sock);
1603                break;
1604        }
1605}
1606#else
1607static inline void xs_reclassify_socket4(struct socket *sock)
1608{
1609}
1610
1611static inline void xs_reclassify_socket6(struct socket *sock)
1612{
1613}
1614
1615static inline void xs_reclassify_socket(int family, struct socket *sock)
1616{
1617}
1618#endif
1619
1620static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1621                struct sock_xprt *transport, int family, int type, int protocol)
1622{
1623        struct socket *sock;
1624        int err;
1625
1626        err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1627        if (err < 0) {
1628                dprintk("RPC:       can't create %d transport socket (%d).\n",
1629                                protocol, -err);
1630                goto out;
1631        }
1632        xs_reclassify_socket(family, sock);
1633
1634        if (xs_bind(transport, sock)) {
1635                sock_release(sock);
1636                goto out;
1637        }
1638
1639        return sock;
1640out:
1641        return ERR_PTR(err);
1642}
1643
1644static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1645{
1646        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1647
1648        if (!transport->inet) {
1649                struct sock *sk = sock->sk;
1650
1651                write_lock_bh(&sk->sk_callback_lock);
1652
1653                xs_save_old_callbacks(transport, sk);
1654
1655                sk->sk_user_data = xprt;
1656                sk->sk_data_ready = xs_udp_data_ready;
1657                sk->sk_write_space = xs_udp_write_space;
1658                sk->sk_error_report = xs_error_report;
1659                sk->sk_no_check = UDP_CSUM_NORCV;
1660                sk->sk_allocation = GFP_ATOMIC;
1661
1662                xprt_set_connected(xprt);
1663
1664                /* Reset to new socket */
1665                transport->sock = sock;
1666                transport->inet = sk;
1667
1668                write_unlock_bh(&sk->sk_callback_lock);
1669        }
1670        xs_udp_do_set_buffer_size(xprt);
1671}
1672
1673static void xs_udp_setup_socket(struct work_struct *work)
1674{
1675        struct sock_xprt *transport =
1676                container_of(work, struct sock_xprt, connect_worker.work);
1677        struct rpc_xprt *xprt = &transport->xprt;
1678        struct socket *sock = transport->sock;
1679        int status = -EIO;
1680
1681        if (xprt->shutdown)
1682                goto out;
1683
1684        /* Start by resetting any existing state */
1685        xs_reset_transport(transport);
1686        sock = xs_create_sock(xprt, transport,
1687                        xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
1688        if (IS_ERR(sock))
1689                goto out;
1690
1691        dprintk("RPC:       worker connecting xprt %p via %s to "
1692                                "%s (port %s)\n", xprt,
1693                        xprt->address_strings[RPC_DISPLAY_PROTO],
1694                        xprt->address_strings[RPC_DISPLAY_ADDR],
1695                        xprt->address_strings[RPC_DISPLAY_PORT]);
1696
1697        xs_udp_finish_connecting(xprt, sock);
1698        status = 0;
1699out:
1700        xprt_clear_connecting(xprt);
1701        xprt_wake_pending_tasks(xprt, status);
1702}
1703
1704/*
1705 * We need to preserve the port number so the reply cache on the server can
1706 * find our cached RPC replies when we get around to reconnecting.
1707 */
1708static void xs_abort_connection(struct sock_xprt *transport)
1709{
1710        int result;
1711        struct sockaddr any;
1712
1713        dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
1714
1715        /*
1716         * Disconnect the transport socket by doing a connect operation
1717         * with AF_UNSPEC.  This should return immediately...
1718         */
1719        memset(&any, 0, sizeof(any));
1720        any.sa_family = AF_UNSPEC;
1721        result = kernel_connect(transport->sock, &any, sizeof(any), 0);
1722        if (!result)
1723                xs_sock_mark_closed(&transport->xprt);
1724        else
1725                dprintk("RPC:       AF_UNSPEC connect return code %d\n",
1726                                result);
1727}
1728
1729static void xs_tcp_reuse_connection(struct sock_xprt *transport)
1730{
1731        unsigned int state = transport->inet->sk_state;
1732
1733        if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
1734                /* we don't need to abort the connection if the socket
1735                 * hasn't undergone a shutdown
1736                 */
1737                if (transport->inet->sk_shutdown == 0)
1738                        return;
1739                dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
1740                                __func__, transport->inet->sk_shutdown);
1741        }
1742        if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
1743                /* we don't need to abort the connection if the socket
1744                 * hasn't undergone a shutdown
1745                 */
1746                if (transport->inet->sk_shutdown == 0)
1747                        return;
1748                dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
1749                                "sk_shutdown set to %d\n",
1750                                __func__, transport->inet->sk_shutdown);
1751        }
1752        xs_abort_connection(transport);
1753}
1754
1755static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1756{
1757        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1758
1759        if (!transport->inet) {
1760                struct sock *sk = sock->sk;
1761
1762                write_lock_bh(&sk->sk_callback_lock);
1763
1764                xs_save_old_callbacks(transport, sk);
1765
1766                sk->sk_user_data = xprt;
1767                sk->sk_data_ready = xs_tcp_data_ready;
1768                sk->sk_state_change = xs_tcp_state_change;
1769                sk->sk_write_space = xs_tcp_write_space;
1770                sk->sk_error_report = xs_error_report;
1771                sk->sk_allocation = GFP_ATOMIC;
1772
1773                /* socket options */
1774                sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1775                sock_reset_flag(sk, SOCK_LINGER);
1776                tcp_sk(sk)->linger2 = 0;
1777                tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1778
1779                xprt_clear_connected(xprt);
1780
1781                /* Reset to new socket */
1782                transport->sock = sock;
1783                transport->inet = sk;
1784
1785                write_unlock_bh(&sk->sk_callback_lock);
1786        }
1787
1788        if (!xprt_bound(xprt))
1789                return -ENOTCONN;
1790
1791        /* Tell the socket layer to start connecting... */
1792        xprt->stat.connect_count++;
1793        xprt->stat.connect_start = jiffies;
1794        return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
1795}
1796
1797/**
1798 * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
1799 * @xprt: RPC transport to connect
1800 * @transport: socket transport to connect
1801 * @create_sock: function to create a socket of the correct type
1802 *
1803 * Invoked by a work queue tasklet.
1804 */
1805static void xs_tcp_setup_socket(struct work_struct *work)
1806{
1807        struct sock_xprt *transport =
1808                container_of(work, struct sock_xprt, connect_worker.work);
1809        struct socket *sock = transport->sock;
1810        struct rpc_xprt *xprt = &transport->xprt;
1811        int status = -EIO;
1812
1813        if (xprt->shutdown)
1814                goto out;
1815
1816        if (!sock) {
1817                clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1818                sock = xs_create_sock(xprt, transport,
1819                                xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
1820                if (IS_ERR(sock)) {
1821                        status = PTR_ERR(sock);
1822                        goto out;
1823                }
1824        } else {
1825                int abort_and_exit;
1826
1827                abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
1828                                &xprt->state);
1829                /* "close" the socket, preserving the local port */
1830                xs_tcp_reuse_connection(transport);
1831
1832                if (abort_and_exit)
1833                        goto out_eagain;
1834        }
1835
1836        dprintk("RPC:       worker connecting xprt %p via %s to "
1837                                "%s (port %s)\n", xprt,
1838                        xprt->address_strings[RPC_DISPLAY_PROTO],
1839                        xprt->address_strings[RPC_DISPLAY_ADDR],
1840                        xprt->address_strings[RPC_DISPLAY_PORT]);
1841
1842        status = xs_tcp_finish_connecting(xprt, sock);
1843        dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1844                        xprt, -status, xprt_connected(xprt),
1845                        sock->sk->sk_state);
1846        switch (status) {
1847        default:
1848                printk("%s: connect returned unhandled error %d\n",
1849                        __func__, status);
1850        case -EADDRNOTAVAIL:
1851                /* We're probably in TIME_WAIT. Get rid of existing socket,
1852                 * and retry
1853                 */
1854                set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1855                xprt_force_disconnect(xprt);
1856                break;
1857        case -ECONNREFUSED:
1858        case -ECONNRESET:
1859        case -ENETUNREACH:
1860                /* retry with existing socket, after a delay */
1861        case 0:
1862        case -EINPROGRESS:
1863        case -EALREADY:
1864                xprt_clear_connecting(xprt);
1865                return;
1866        case -EINVAL:
1867                /* Happens, for instance, if the user specified a link
1868                 * local IPv6 address without a scope-id.
1869                 */
1870                goto out;
1871        }
1872out_eagain:
1873        status = -EAGAIN;
1874out:
1875        xprt_clear_connecting(xprt);
1876        xprt_wake_pending_tasks(xprt, status);
1877}
1878
1879/**
1880 * xs_connect - connect a socket to a remote endpoint
1881 * @task: address of RPC task that manages state of connect request
1882 *
1883 * TCP: If the remote end dropped the connection, delay reconnecting.
1884 *
1885 * UDP socket connects are synchronous, but we use a work queue anyway
1886 * to guarantee that even unprivileged user processes can set up a
1887 * socket on a privileged port.
1888 *
1889 * If a UDP socket connect fails, the delay behavior here prevents
1890 * retry floods (hard mounts).
1891 */
1892static void xs_connect(struct rpc_task *task)
1893{
1894        struct rpc_xprt *xprt = task->tk_xprt;
1895        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1896
1897        if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
1898                dprintk("RPC:       xs_connect delayed xprt %p for %lu "
1899                                "seconds\n",
1900                                xprt, xprt->reestablish_timeout / HZ);
1901                queue_delayed_work(rpciod_workqueue,
1902                                   &transport->connect_worker,
1903                                   xprt->reestablish_timeout);
1904                xprt->reestablish_timeout <<= 1;
1905                if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1906                        xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1907                if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
1908                        xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
1909        } else {
1910                dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
1911                queue_delayed_work(rpciod_workqueue,
1912                                   &transport->connect_worker, 0);
1913        }
1914}
1915
1916/**
1917 * xs_udp_print_stats - display UDP socket-specifc stats
1918 * @xprt: rpc_xprt struct containing statistics
1919 * @seq: output file
1920 *
1921 */
1922static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1923{
1924        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1925
1926        seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1927                        transport->srcport,
1928                        xprt->stat.bind_count,
1929                        xprt->stat.sends,
1930                        xprt->stat.recvs,
1931                        xprt->stat.bad_xids,
1932                        xprt->stat.req_u,
1933                        xprt->stat.bklog_u);
1934}
1935
1936/**
1937 * xs_tcp_print_stats - display TCP socket-specifc stats
1938 * @xprt: rpc_xprt struct containing statistics
1939 * @seq: output file
1940 *
1941 */
1942static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1943{
1944        struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1945        long idle_time = 0;
1946
1947        if (xprt_connected(xprt))
1948                idle_time = (long)(jiffies - xprt->last_used) / HZ;
1949
1950        seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1951                        transport->srcport,
1952                        xprt->stat.bind_count,
1953                        xprt->stat.connect_count,
1954                        xprt->stat.connect_time,
1955                        idle_time,
1956                        xprt->stat.sends,
1957                        xprt->stat.recvs,
1958                        xprt->stat.bad_xids,
1959                        xprt->stat.req_u,
1960                        xprt->stat.bklog_u);
1961}
1962
1963/*
1964 * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
1965 * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
1966 * to use the server side send routines.
1967 */
1968static void *bc_malloc(struct rpc_task *task, size_t size)
1969{
1970        struct page *page;
1971        struct rpc_buffer *buf;
1972
1973        BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
1974        page = alloc_page(GFP_KERNEL);
1975
1976        if (!page)
1977                return NULL;
1978
1979        buf = page_address(page);
1980        buf->len = PAGE_SIZE;
1981
1982        return buf->data;
1983}
1984
1985/*
1986 * Free the space allocated in the bc_alloc routine
1987 */
1988static void bc_free(void *buffer)
1989{
1990        struct rpc_buffer *buf;
1991
1992        if (!buffer)
1993                return;
1994
1995        buf = container_of(buffer, struct rpc_buffer, data);
1996        free_page((unsigned long)buf);
1997}
1998
1999/*
2000 * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2001 * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2002 */
2003static int bc_sendto(struct rpc_rqst *req)
2004{
2005        int len;
2006        struct xdr_buf *xbufp = &req->rq_snd_buf;
2007        struct rpc_xprt *xprt = req->rq_xprt;
2008        struct sock_xprt *transport =
2009                                container_of(xprt, struct sock_xprt, xprt);
2010        struct socket *sock = transport->sock;
2011        unsigned long headoff;
2012        unsigned long tailoff;
2013
2014        /*
2015         * Set up the rpc header and record marker stuff
2016         */
2017        xs_encode_tcp_record_marker(xbufp);
2018
2019        tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2020        headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2021        len = svc_send_common(sock, xbufp,
2022                              virt_to_page(xbufp->head[0].iov_base), headoff,
2023                              xbufp->tail[0].iov_base, tailoff);
2024
2025        if (len != xbufp->len) {
2026                printk(KERN_NOTICE "Error sending entire callback!\n");
2027                len = -EAGAIN;
2028        }
2029
2030        return len;
2031}
2032
2033/*
2034 * The send routine. Borrows from svc_send
2035 */
2036static int bc_send_request(struct rpc_task *task)
2037{
2038        struct rpc_rqst *req = task->tk_rqstp;
2039        struct svc_xprt *xprt;
2040        struct svc_sock         *svsk;
2041        u32                     len;
2042
2043        dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2044        /*
2045         * Get the server socket associated with this callback xprt
2046         */
2047        xprt = req->rq_xprt->bc_xprt;
2048        svsk = container_of(xprt, struct svc_sock, sk_xprt);
2049
2050        /*
2051         * Grab the mutex to serialize data as the connection is shared
2052         * with the fore channel
2053         */
2054        if (!mutex_trylock(&xprt->xpt_mutex)) {
2055                rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2056                if (!mutex_trylock(&xprt->xpt_mutex))
2057                        return -EAGAIN;
2058                rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2059        }
2060        if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2061                len = -ENOTCONN;
2062        else
2063                len = bc_sendto(req);
2064        mutex_unlock(&xprt->xpt_mutex);
2065
2066        if (len > 0)
2067                len = 0;
2068
2069        return len;
2070}
2071
2072/*
2073 * The close routine. Since this is client initiated, we do nothing
2074 */
2075
2076static void bc_close(struct rpc_xprt *xprt)
2077{
2078}
2079
2080/*
2081 * The xprt destroy routine. Again, because this connection is client
2082 * initiated, we do nothing
2083 */
2084
2085static void bc_destroy(struct rpc_xprt *xprt)
2086{
2087}
2088
2089static struct rpc_xprt_ops xs_udp_ops = {
2090        .set_buffer_size        = xs_udp_set_buffer_size,
2091        .reserve_xprt           = xprt_reserve_xprt_cong,
2092        .release_xprt           = xprt_release_xprt_cong,
2093        .rpcbind                = rpcb_getport_async,
2094        .set_port               = xs_set_port,
2095        .connect                = xs_connect,
2096        .buf_alloc              = rpc_malloc,
2097        .buf_free               = rpc_free,
2098        .send_request           = xs_udp_send_request,
2099        .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2100        .timer                  = xs_udp_timer,
2101        .release_request        = xprt_release_rqst_cong,
2102        .close                  = xs_close,
2103        .destroy                = xs_destroy,
2104        .print_stats            = xs_udp_print_stats,
2105};
2106
2107static struct rpc_xprt_ops xs_tcp_ops = {
2108        .reserve_xprt           = xprt_reserve_xprt,
2109        .release_xprt           = xs_tcp_release_xprt,
2110        .rpcbind                = rpcb_getport_async,
2111        .set_port               = xs_set_port,
2112        .connect                = xs_connect,
2113        .buf_alloc              = rpc_malloc,
2114        .buf_free               = rpc_free,
2115        .send_request           = xs_tcp_send_request,
2116        .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2117        .close                  = xs_tcp_close,
2118        .destroy                = xs_destroy,
2119        .print_stats            = xs_tcp_print_stats,
2120};
2121
2122/*
2123 * The rpc_xprt_ops for the server backchannel
2124 */
2125
2126static struct rpc_xprt_ops bc_tcp_ops = {
2127        .reserve_xprt           = xprt_reserve_xprt,
2128        .release_xprt           = xprt_release_xprt,
2129        .buf_alloc              = bc_malloc,
2130        .buf_free               = bc_free,
2131        .send_request           = bc_send_request,
2132        .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2133        .close                  = bc_close,
2134        .destroy                = bc_destroy,
2135        .print_stats            = xs_tcp_print_stats,
2136};
2137
2138static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2139{
2140        static const struct sockaddr_in sin = {
2141                .sin_family             = AF_INET,
2142                .sin_addr.s_addr        = htonl(INADDR_ANY),
2143        };
2144        static const struct sockaddr_in6 sin6 = {
2145                .sin6_family            = AF_INET6,
2146                .sin6_addr              = IN6ADDR_ANY_INIT,
2147        };
2148
2149        switch (family) {
2150        case AF_INET:
2151                memcpy(sap, &sin, sizeof(sin));
2152                break;
2153        case AF_INET6:
2154                memcpy(sap, &sin6, sizeof(sin6));
2155                break;
2156        default:
2157                dprintk("RPC:       %s: Bad address family\n", __func__);
2158                return -EAFNOSUPPORT;
2159        }
2160        return 0;
2161}
2162
2163static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2164                                      unsigned int slot_table_size)
2165{
2166        struct rpc_xprt *xprt;
2167        struct sock_xprt *new;
2168
2169        if (args->addrlen > sizeof(xprt->addr)) {
2170                dprintk("RPC:       xs_setup_xprt: address too large\n");
2171                return ERR_PTR(-EBADF);
2172        }
2173
2174        xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size);
2175        if (xprt == NULL) {
2176                dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2177                                "rpc_xprt\n");
2178                return ERR_PTR(-ENOMEM);
2179        }
2180
2181        new = container_of(xprt, struct sock_xprt, xprt);
2182        memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2183        xprt->addrlen = args->addrlen;
2184        if (args->srcaddr)
2185                memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2186        else {
2187                int err;
2188                err = xs_init_anyaddr(args->dstaddr->sa_family,
2189                                        (struct sockaddr *)&new->srcaddr);
2190                if (err != 0)
2191                        return ERR_PTR(err);
2192        }
2193
2194        return xprt;
2195}
2196
2197static const struct rpc_timeout xs_udp_default_timeout = {
2198        .to_initval = 5 * HZ,
2199        .to_maxval = 30 * HZ,
2200        .to_increment = 5 * HZ,
2201        .to_retries = 5,
2202};
2203
2204/**
2205 * xs_setup_udp - Set up transport to use a UDP socket
2206 * @args: rpc transport creation arguments
2207 *
2208 */
2209static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2210{
2211        struct sockaddr *addr = args->dstaddr;
2212        struct rpc_xprt *xprt;
2213        struct sock_xprt *transport;
2214        struct rpc_xprt *ret;
2215
2216        xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
2217        if (IS_ERR(xprt))
2218                return xprt;
2219        transport = container_of(xprt, struct sock_xprt, xprt);
2220
2221        xprt->prot = IPPROTO_UDP;
2222        xprt->tsh_size = 0;
2223        /* XXX: header size can vary due to auth type, IPv6, etc. */
2224        xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2225
2226        xprt->bind_timeout = XS_BIND_TO;
2227        xprt->reestablish_timeout = XS_UDP_REEST_TO;
2228        xprt->idle_timeout = XS_IDLE_DISC_TO;
2229
2230        xprt->ops = &xs_udp_ops;
2231
2232        xprt->timeout = &xs_udp_default_timeout;
2233
2234        switch (addr->sa_family) {
2235        case AF_INET:
2236                if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2237                        xprt_set_bound(xprt);
2238
2239                INIT_DELAYED_WORK(&transport->connect_worker,
2240                                        xs_udp_setup_socket);
2241                xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2242                break;
2243        case AF_INET6:
2244                if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2245                        xprt_set_bound(xprt);
2246
2247                INIT_DELAYED_WORK(&transport->connect_worker,
2248                                        xs_udp_setup_socket);
2249                xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2250                break;
2251        default:
2252                ret = ERR_PTR(-EAFNOSUPPORT);
2253                goto out_err;
2254        }
2255
2256        if (xprt_bound(xprt))
2257                dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2258                                xprt->address_strings[RPC_DISPLAY_ADDR],
2259                                xprt->address_strings[RPC_DISPLAY_PORT],
2260                                xprt->address_strings[RPC_DISPLAY_PROTO]);
2261        else
2262                dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2263                                xprt->address_strings[RPC_DISPLAY_ADDR],
2264                                xprt->address_strings[RPC_DISPLAY_PROTO]);
2265
2266        if (try_module_get(THIS_MODULE))
2267                return xprt;
2268        ret = ERR_PTR(-EINVAL);
2269out_err:
2270        xprt_free(xprt);
2271        return ret;
2272}
2273
2274static const struct rpc_timeout xs_tcp_default_timeout = {
2275        .to_initval = 60 * HZ,
2276        .to_maxval = 60 * HZ,
2277        .to_retries = 2,
2278};
2279
2280/**
2281 * xs_setup_tcp - Set up transport to use a TCP socket
2282 * @args: rpc transport creation arguments
2283 *
2284 */
2285static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2286{
2287        struct sockaddr *addr = args->dstaddr;
2288        struct rpc_xprt *xprt;
2289        struct sock_xprt *transport;
2290        struct rpc_xprt *ret;
2291
2292        xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2293        if (IS_ERR(xprt))
2294                return xprt;
2295        transport = container_of(xprt, struct sock_xprt, xprt);
2296
2297        xprt->prot = IPPROTO_TCP;
2298        xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2299        xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2300
2301        xprt->bind_timeout = XS_BIND_TO;
2302        xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2303        xprt->idle_timeout = XS_IDLE_DISC_TO;
2304
2305        xprt->ops = &xs_tcp_ops;
2306        xprt->timeout = &xs_tcp_default_timeout;
2307
2308        switch (addr->sa_family) {
2309        case AF_INET:
2310                if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2311                        xprt_set_bound(xprt);
2312
2313                INIT_DELAYED_WORK(&transport->connect_worker,
2314                                        xs_tcp_setup_socket);
2315                xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2316                break;
2317        case AF_INET6:
2318                if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2319                        xprt_set_bound(xprt);
2320
2321                INIT_DELAYED_WORK(&transport->connect_worker,
2322                                        xs_tcp_setup_socket);
2323                xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2324                break;
2325        default:
2326                ret = ERR_PTR(-EAFNOSUPPORT);
2327                goto out_err;
2328        }
2329
2330        if (xprt_bound(xprt))
2331                dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2332                                xprt->address_strings[RPC_DISPLAY_ADDR],
2333                                xprt->address_strings[RPC_DISPLAY_PORT],
2334                                xprt->address_strings[RPC_DISPLAY_PROTO]);
2335        else
2336                dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2337                                xprt->address_strings[RPC_DISPLAY_ADDR],
2338                                xprt->address_strings[RPC_DISPLAY_PROTO]);
2339
2340
2341        if (try_module_get(THIS_MODULE))
2342                return xprt;
2343        ret = ERR_PTR(-EINVAL);
2344out_err:
2345        xprt_free(xprt);
2346        return ret;
2347}
2348
2349/**
2350 * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2351 * @args: rpc transport creation arguments
2352 *
2353 */
2354static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2355{
2356        struct sockaddr *addr = args->dstaddr;
2357        struct rpc_xprt *xprt;
2358        struct sock_xprt *transport;
2359        struct svc_sock *bc_sock;
2360        struct rpc_xprt *ret;
2361
2362        xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2363        if (IS_ERR(xprt))
2364                return xprt;
2365        transport = container_of(xprt, struct sock_xprt, xprt);
2366
2367        xprt->prot = IPPROTO_TCP;
2368        xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2369        xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2370        xprt->timeout = &xs_tcp_default_timeout;
2371
2372        /* backchannel */
2373        xprt_set_bound(xprt);
2374        xprt->bind_timeout = 0;
2375        xprt->reestablish_timeout = 0;
2376        xprt->idle_timeout = 0;
2377
2378        /*
2379         * The backchannel uses the same socket connection as the
2380         * forechannel
2381         */
2382        xprt->bc_xprt = args->bc_xprt;
2383        bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2384        bc_sock->sk_bc_xprt = xprt;
2385        transport->sock = bc_sock->sk_sock;
2386        transport->inet = bc_sock->sk_sk;
2387
2388        xprt->ops = &bc_tcp_ops;
2389
2390        switch (addr->sa_family) {
2391        case AF_INET:
2392                xs_format_peer_addresses(xprt, "tcp",
2393                                         RPCBIND_NETID_TCP);
2394                break;
2395        case AF_INET6:
2396                xs_format_peer_addresses(xprt, "tcp",
2397                                   RPCBIND_NETID_TCP6);
2398                break;
2399        default:
2400                ret = ERR_PTR(-EAFNOSUPPORT);
2401                goto out_err;
2402        }
2403
2404        dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2405                        xprt->address_strings[RPC_DISPLAY_ADDR],
2406                        xprt->address_strings[RPC_DISPLAY_PORT],
2407                        xprt->address_strings[RPC_DISPLAY_PROTO]);
2408
2409        /*
2410         * Since we don't want connections for the backchannel, we set
2411         * the xprt status to connected
2412         */
2413        xprt_set_connected(xprt);
2414
2415
2416        if (try_module_get(THIS_MODULE))
2417                return xprt;
2418        ret = ERR_PTR(-EINVAL);
2419out_err:
2420        xprt_free(xprt);
2421        return ret;
2422}
2423
2424static struct xprt_class        xs_udp_transport = {
2425        .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2426        .name           = "udp",
2427        .owner          = THIS_MODULE,
2428        .ident          = XPRT_TRANSPORT_UDP,
2429        .setup          = xs_setup_udp,
2430};
2431
2432static struct xprt_class        xs_tcp_transport = {
2433        .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
2434        .name           = "tcp",
2435        .owner          = THIS_MODULE,
2436        .ident          = XPRT_TRANSPORT_TCP,
2437        .setup          = xs_setup_tcp,
2438};
2439
2440static struct xprt_class        xs_bc_tcp_transport = {
2441        .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2442        .name           = "tcp NFSv4.1 backchannel",
2443        .owner          = THIS_MODULE,
2444        .ident          = XPRT_TRANSPORT_BC_TCP,
2445        .setup          = xs_setup_bc_tcp,
2446};
2447
2448/**
2449 * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
2450 *
2451 */
2452int init_socket_xprt(void)
2453{
2454#ifdef RPC_DEBUG
2455        if (!sunrpc_table_header)
2456                sunrpc_table_header = register_sysctl_table(sunrpc_table);
2457#endif
2458
2459        xprt_register_transport(&xs_udp_transport);
2460        xprt_register_transport(&xs_tcp_transport);
2461        xprt_register_transport(&xs_bc_tcp_transport);
2462
2463        return 0;
2464}
2465
2466/**
2467 * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
2468 *
2469 */
2470void cleanup_socket_xprt(void)
2471{
2472#ifdef RPC_DEBUG
2473        if (sunrpc_table_header) {
2474                unregister_sysctl_table(sunrpc_table_header);
2475                sunrpc_table_header = NULL;
2476        }
2477#endif
2478
2479        xprt_unregister_transport(&xs_udp_transport);
2480        xprt_unregister_transport(&xs_tcp_transport);
2481        xprt_unregister_transport(&xs_bc_tcp_transport);
2482}
2483
2484static int param_set_uint_minmax(const char *val,
2485                const struct kernel_param *kp,
2486                unsigned int min, unsigned int max)
2487{
2488        unsigned long num;
2489        int ret;
2490
2491        if (!val)
2492                return -EINVAL;
2493        ret = strict_strtoul(val, 0, &num);
2494        if (ret == -EINVAL || num < min || num > max)
2495                return -EINVAL;
2496        *((unsigned int *)kp->arg) = num;
2497        return 0;
2498}
2499
2500static int param_set_portnr(const char *val, const struct kernel_param *kp)
2501{
2502        return param_set_uint_minmax(val, kp,
2503                        RPC_MIN_RESVPORT,
2504                        RPC_MAX_RESVPORT);
2505}
2506
2507static struct kernel_param_ops param_ops_portnr = {
2508        .set = param_set_portnr,
2509        .get = param_get_uint,
2510};
2511
2512#define param_check_portnr(name, p) \
2513        __param_check(name, p, unsigned int);
2514
2515module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
2516module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
2517
2518static int param_set_slot_table_size(const char *val,
2519                                     const struct kernel_param *kp)
2520{
2521        return param_set_uint_minmax(val, kp,
2522                        RPC_MIN_SLOT_TABLE,
2523                        RPC_MAX_SLOT_TABLE);
2524}
2525
2526static struct kernel_param_ops param_ops_slot_table_size = {
2527        .set = param_set_slot_table_size,
2528        .get = param_get_uint,
2529};
2530
2531#define param_check_slot_table_size(name, p) \
2532        __param_check(name, p, unsigned int);
2533
2534module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
2535                   slot_table_size, 0644);
2536module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
2537                   slot_table_size, 0644);
2538
2539
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