net/sunrpc/xprtsock.c

   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 Software <alan@redhat.com>
   7  * TCP send fixes (C) 1998 Red Hat Software <alan@redhat.com>
   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
  18 #include <linux/types.h>
  19 #include <linux/slab.h>
  20 #include <linux/capability.h>
  21 #include <linux/sched.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/errno.h>
  24 #include <linux/socket.h>
  25 #include <linux/in.h>
  26 #include <linux/net.h>
  27 #include <linux/mm.h>
  28 #include <linux/udp.h>
  29 #include <linux/tcp.h>
  30 #include <linux/sunrpc/clnt.h>
  31 #include <linux/sunrpc/sched.h>
  32 #include <linux/file.h>
  33
  34 #include <net/sock.h>
  35 #include <net/checksum.h>
  36 #include <net/udp.h>
  37 #include <net/tcp.h>
  38
  39 /*
  40  * xprtsock tunables
  41  */
  42 unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  43 unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  44
  45 unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  46 unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  47
  48 /*
  49  * How many times to try sending a request on a socket before waiting
  50  * for the socket buffer to clear.
  51  */
  52 #define XS_SENDMSG_RETRY        (10U)
  53
  54 /*
  55  * Time out for an RPC UDP socket connect.  UDP socket connects are
  56  * synchronous, but we set a timeout anyway in case of resource
  57  * exhaustion on the local host.
  58  */
  59 #define XS_UDP_CONN_TO          (5U * HZ)
  60
  61 /*
  62  * Wait duration for an RPC TCP connection to be established.  Solaris
  63  * NFS over TCP uses 60 seconds, for example, which is in line with how
  64  * long a server takes to reboot.
  65  */
  66 #define XS_TCP_CONN_TO          (60U * HZ)
  67
  68 /*
  69  * Wait duration for a reply from the RPC portmapper.
  70  */
  71 #define XS_BIND_TO              (60U * HZ)
  72
  73 /*
  74  * Delay if a UDP socket connect error occurs.  This is most likely some
  75  * kind of resource problem on the local host.
  76  */
  77 #define XS_UDP_REEST_TO         (2U * HZ)
  78
  79 /*
  80  * The reestablish timeout allows clients to delay for a bit before attempting
  81  * to reconnect to a server that just dropped our connection.
  82  *
  83  * We implement an exponential backoff when trying to reestablish a TCP
  84  * transport connection with the server.  Some servers like to drop a TCP
  85  * connection when they are overworked, so we start with a short timeout and
  86  * increase over time if the server is down or not responding.
  87  */
  88 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
  89 #define XS_TCP_MAX_REEST_TO     (5U * 60 * HZ)
  90
  91 /*
  92  * TCP idle timeout; client drops the transport socket if it is idle
  93  * for this long.  Note that we also timeout UDP sockets to prevent
  94  * holding port numbers when there is no RPC traffic.
  95  */
  96 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
  97
  98 #ifdef RPC_DEBUG
  99 # undef  RPC_DEBUG_DATA
 100 # define RPCDBG_FACILITY        RPCDBG_TRANS
 101 #endif
 102
 103 #ifdef RPC_DEBUG_DATA
 104 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 105 {
 106         u8 *buf = (u8 *) packet;
 107         int j;
 108
 109         dprintk("RPC:      %s\n", msg);
 110         for (j = 0; j < count && j < 128; j += 4) {
 111                 if (!(j & 31)) {
 112                         if (j)
 113                                 dprintk("\n");
 114                         dprintk("0x%04x ", j);
 115                 }
 116                 dprintk("%02x%02x%02x%02x ",
 117                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 118         }
 119         dprintk("\n");
 120 }
 121 #else
 122 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 123 {
 124         /* NOP */
 125 }
 126 #endif
 127
 128 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 129
 130 static inline int xs_send_head(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, unsigned int len)
 131 {
 132         struct kvec iov = {
 133                 .iov_base       = xdr->head[0].iov_base + base,
 134                 .iov_len        = len - base,
 135         };
 136         struct msghdr msg = {
 137                 .msg_name       = addr,
 138                 .msg_namelen    = addrlen,
 139                 .msg_flags      = XS_SENDMSG_FLAGS,
 140         };
 141
 142         if (xdr->len > len)
 143                 msg.msg_flags |= MSG_MORE;
 144
 145         if (likely(iov.iov_len))
 146                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 147         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 148 }
 149
 150 static int xs_send_tail(struct socket *sock, struct xdr_buf *xdr, unsigned int base, unsigned int len)
 151 {
 152         struct kvec iov = {
 153                 .iov_base       = xdr->tail[0].iov_base + base,
 154                 .iov_len        = len - base,
 155         };
 156         struct msghdr msg = {
 157                 .msg_flags      = XS_SENDMSG_FLAGS,
 158         };
 159
 160         return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 161 }
 162
 163 /**
 164  * xs_sendpages - write pages directly to a socket
 165  * @sock: socket to send on
 166  * @addr: UDP only -- address of destination
 167  * @addrlen: UDP only -- length of destination address
 168  * @xdr: buffer containing this request
 169  * @base: starting position in the buffer
 170  *
 171  */
 172 static inline int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
 173 {
 174         struct page **ppage = xdr->pages;
 175         unsigned int len, pglen = xdr->page_len;
 176         int err, ret = 0;
 177         ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
 178
 179         if (unlikely(!sock))
 180                 return -ENOTCONN;
 181
 182         clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 183
 184         len = xdr->head[0].iov_len;
 185         if (base < len || (addr != NULL && base == 0)) {
 186                 err = xs_send_head(sock, addr, addrlen, xdr, base, len);
 187                 if (ret == 0)
 188                         ret = err;
 189                 else if (err > 0)
 190                         ret += err;
 191                 if (err != (len - base))
 192                         goto out;
 193                 base = 0;
 194         } else
 195                 base -= len;
 196
 197         if (unlikely(pglen == 0))
 198                 goto copy_tail;
 199         if (unlikely(base >= pglen)) {
 200                 base -= pglen;
 201                 goto copy_tail;
 202         }
 203         if (base || xdr->page_base) {
 204                 pglen -= base;
 205                 base += xdr->page_base;
 206                 ppage += base >> PAGE_CACHE_SHIFT;
 207                 base &= ~PAGE_CACHE_MASK;
 208         }
 209
 210         sendpage = sock->ops->sendpage ? : sock_no_sendpage;
 211         do {
 212                 int flags = XS_SENDMSG_FLAGS;
 213
 214                 len = PAGE_CACHE_SIZE;
 215                 if (base)
 216                         len -= base;
 217                 if (pglen < len)
 218                         len = pglen;
 219
 220                 if (pglen != len || xdr->tail[0].iov_len != 0)
 221                         flags |= MSG_MORE;
 222
 223                 /* Hmm... We might be dealing with highmem pages */
 224                 if (PageHighMem(*ppage))
 225                         sendpage = sock_no_sendpage;
 226                 err = sendpage(sock, *ppage, base, len, flags);
 227                 if (ret == 0)
 228                         ret = err;
 229                 else if (err > 0)
 230                         ret += err;
 231                 if (err != len)
 232                         goto out;
 233                 base = 0;
 234                 ppage++;
 235         } while ((pglen -= len) != 0);
 236 copy_tail:
 237         len = xdr->tail[0].iov_len;
 238         if (base < len) {
 239                 err = xs_send_tail(sock, xdr, base, len);
 240                 if (ret == 0)
 241                         ret = err;
 242                 else if (err > 0)
 243                         ret += err;
 244         }
 245 out:
 246         return ret;
 247 }
 248
 249 /**
 250  * xs_nospace - place task on wait queue if transmit was incomplete
 251  * @task: task to put to sleep
 252  *
 253  */
 254 static void xs_nospace(struct rpc_task *task)
 255 {
 256         struct rpc_rqst *req = task->tk_rqstp;
 257         struct rpc_xprt *xprt = req->rq_xprt;
 258
 259         dprintk("RPC: %4d xmit incomplete (%u left of %u)\n",
 260                         task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 261                         req->rq_slen);
 262
 263         if (test_bit(SOCK_ASYNC_NOSPACE, &xprt->sock->flags)) {
 264                 /* Protect against races with write_space */
 265                 spin_lock_bh(&xprt->transport_lock);
 266
 267                 /* Don't race with disconnect */
 268                 if (!xprt_connected(xprt))
 269                         task->tk_status = -ENOTCONN;
 270                 else if (test_bit(SOCK_NOSPACE, &xprt->sock->flags))
 271                         xprt_wait_for_buffer_space(task);
 272
 273                 spin_unlock_bh(&xprt->transport_lock);
 274         } else
 275                 /* Keep holding the socket if it is blocked */
 276                 rpc_delay(task, HZ>>4);
 277 }
 278
 279 /**
 280  * xs_udp_send_request - write an RPC request to a UDP socket
 281  * @task: address of RPC task that manages the state of an RPC request
 282  *
 283  * Return values:
 284  *        0:    The request has been sent
 285  *   EAGAIN:    The socket was blocked, please call again later to
 286  *              complete the request
 287  * ENOTCONN:    Caller needs to invoke connect logic then call again
 288  *    other:    Some other error occured, the request was not sent
 289  */
 290 static int xs_udp_send_request(struct rpc_task *task)
 291 {
 292         struct rpc_rqst *req = task->tk_rqstp;
 293         struct rpc_xprt *xprt = req->rq_xprt;
 294         struct xdr_buf *xdr = &req->rq_snd_buf;
 295         int status;
 296
 297         xs_pktdump("packet data:",
 298                                 req->rq_svec->iov_base,
 299                                 req->rq_svec->iov_len);
 300
 301         req->rq_xtime = jiffies;
 302         status = xs_sendpages(xprt->sock, (struct sockaddr *) &xprt->addr,
 303                                 sizeof(xprt->addr), xdr, req->rq_bytes_sent);
 304
 305         dprintk("RPC:      xs_udp_send_request(%u) = %d\n",
 306                         xdr->len - req->rq_bytes_sent, status);
 307
 308         if (likely(status >= (int) req->rq_slen))
 309                 return 0;
 310
 311         /* Still some bytes left; set up for a retry later. */
 312         if (status > 0)
 313                 status = -EAGAIN;
 314
 315         switch (status) {
 316         case -ENETUNREACH:
 317         case -EPIPE:
 318         case -ECONNREFUSED:
 319                 /* When the server has died, an ICMP port unreachable message
 320                  * prompts ECONNREFUSED. */
 321                 break;
 322         case -EAGAIN:
 323                 xs_nospace(task);
 324                 break;
 325         default:
 326                 dprintk("RPC:      sendmsg returned unrecognized error %d\n",
 327                         -status);
 328                 break;
 329         }
 330
 331         return status;
 332 }
 333
 334 static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf)
 335 {
 336         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 337         rpc_fraghdr *base = buf->head[0].iov_base;
 338         *base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen);
 339 }
 340
 341 /**
 342  * xs_tcp_send_request - write an RPC request to a TCP socket
 343  * @task: address of RPC task that manages the state of an RPC request
 344  *
 345  * Return values:
 346  *        0:    The request has been sent
 347  *   EAGAIN:    The socket was blocked, please call again later to
 348  *              complete the request
 349  * ENOTCONN:    Caller needs to invoke connect logic then call again
 350  *    other:    Some other error occured, the request was not sent
 351  *
 352  * XXX: In the case of soft timeouts, should we eventually give up
 353  *      if sendmsg is not able to make progress?
 354  */
 355 static int xs_tcp_send_request(struct rpc_task *task)
 356 {
 357         struct rpc_rqst *req = task->tk_rqstp;
 358         struct rpc_xprt *xprt = req->rq_xprt;
 359         struct xdr_buf *xdr = &req->rq_snd_buf;
 360         int status, retry = 0;
 361
 362         xs_encode_tcp_record_marker(&req->rq_snd_buf);
 363
 364         xs_pktdump("packet data:",
 365                                 req->rq_svec->iov_base,
 366                                 req->rq_svec->iov_len);
 367
 368         /* Continue transmitting the packet/record. We must be careful
 369          * to cope with writespace callbacks arriving _after_ we have
 370          * called sendmsg(). */
 371         while (1) {
 372                 req->rq_xtime = jiffies;
 373                 status = xs_sendpages(xprt->sock, NULL, 0, xdr,
 374                                                 req->rq_bytes_sent);
 375
 376                 dprintk("RPC:      xs_tcp_send_request(%u) = %d\n",
 377                                 xdr->len - req->rq_bytes_sent, status);
 378
 379                 if (unlikely(status < 0))
 380                         break;
 381
 382                 /* If we've sent the entire packet, immediately
 383                  * reset the count of bytes sent. */
 384                 req->rq_bytes_sent += status;
 385                 task->tk_bytes_sent += status;
 386                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 387                         req->rq_bytes_sent = 0;
 388                         return 0;
 389                 }
 390
 391                 status = -EAGAIN;
 392                 if (retry++ > XS_SENDMSG_RETRY)
 393                         break;
 394         }
 395
 396         switch (status) {
 397         case -EAGAIN:
 398                 xs_nospace(task);
 399                 break;
 400         case -ECONNREFUSED:
 401         case -ECONNRESET:
 402         case -ENOTCONN:
 403         case -EPIPE:
 404                 status = -ENOTCONN;
 405                 break;
 406         default:
 407                 dprintk("RPC:      sendmsg returned unrecognized error %d\n",
 408                         -status);
 409                 xprt_disconnect(xprt);
 410                 break;
 411         }
 412
 413         return status;
 414 }
 415
 416 /**
 417  * xs_tcp_release_xprt - clean up after a tcp transmission
 418  * @xprt: transport
 419  * @task: rpc task
 420  *
 421  * This cleans up if an error causes us to abort the transmission of a request.
 422  * In this case, the socket may need to be reset in order to avoid confusing
 423  * the server.
 424  */
 425 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 426 {
 427         struct rpc_rqst *req;
 428
 429         if (task != xprt->snd_task)
 430                 return;
 431         if (task == NULL)
 432                 goto out_release;
 433         req = task->tk_rqstp;
 434         if (req->rq_bytes_sent == 0)
 435                 goto out_release;
 436         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 437                 goto out_release;
 438         set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
 439 out_release:
 440         xprt_release_xprt(xprt, task);
 441 }
 442
 443 /**
 444  * xs_close - close a socket
 445  * @xprt: transport
 446  *
 447  * This is used when all requests are complete; ie, no DRC state remains
 448  * on the server we want to save.
 449  */
 450 static void xs_close(struct rpc_xprt *xprt)
 451 {
 452         struct socket *sock = xprt->sock;
 453         struct sock *sk = xprt->inet;
 454
 455         if (!sk)
 456                 goto clear_close_wait;
 457
 458         dprintk("RPC:      xs_close xprt %p\n", xprt);
 459
 460         write_lock_bh(&sk->sk_callback_lock);
 461         xprt->inet = NULL;
 462         xprt->sock = NULL;
 463
 464         sk->sk_user_data = NULL;
 465         sk->sk_data_ready = xprt->old_data_ready;
 466         sk->sk_state_change = xprt->old_state_change;
 467         sk->sk_write_space = xprt->old_write_space;
 468         write_unlock_bh(&sk->sk_callback_lock);
 469
 470         sk->sk_no_check = 0;
 471
 472         sock_release(sock);
 473 clear_close_wait:
 474         smp_mb__before_clear_bit();
 475         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 476         smp_mb__after_clear_bit();
 477 }
 478
 479 /**
 480  * xs_destroy - prepare to shutdown a transport
 481  * @xprt: doomed transport
 482  *
 483  */
 484 static void xs_destroy(struct rpc_xprt *xprt)
 485 {
 486         dprintk("RPC:      xs_destroy xprt %p\n", xprt);
 487
 488         cancel_delayed_work(&xprt->connect_worker);
 489         flush_scheduled_work();
 490
 491         xprt_disconnect(xprt);
 492         xs_close(xprt);
 493         kfree(xprt->slot);
 494 }
 495
 496 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 497 {
 498         return (struct rpc_xprt *) sk->sk_user_data;
 499 }
 500
 501 /**
 502  * xs_udp_data_ready - "data ready" callback for UDP sockets
 503  * @sk: socket with data to read
 504  * @len: how much data to read
 505  *
 506  */
 507 static void xs_udp_data_ready(struct sock *sk, int len)
 508 {
 509         struct rpc_task *task;
 510         struct rpc_xprt *xprt;
 511         struct rpc_rqst *rovr;
 512         struct sk_buff *skb;
 513         int err, repsize, copied;
 514         u32 _xid, *xp;
 515
 516         read_lock(&sk->sk_callback_lock);
 517         dprintk("RPC:      xs_udp_data_ready...\n");
 518         if (!(xprt = xprt_from_sock(sk)))
 519                 goto out;
 520
 521         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 522                 goto out;
 523
 524         if (xprt->shutdown)
 525                 goto dropit;
 526
 527         repsize = skb->len - sizeof(struct udphdr);
 528         if (repsize < 4) {
 529                 dprintk("RPC:      impossible RPC reply size %d!\n", repsize);
 530                 goto dropit;
 531         }
 532
 533         /* Copy the XID from the skb... */
 534         xp = skb_header_pointer(skb, sizeof(struct udphdr),
 535                                 sizeof(_xid), &_xid);
 536         if (xp == NULL)
 537                 goto dropit;
 538
 539         /* Look up and lock the request corresponding to the given XID */
 540         spin_lock(&xprt->transport_lock);
 541         rovr = xprt_lookup_rqst(xprt, *xp);
 542         if (!rovr)
 543                 goto out_unlock;
 544         task = rovr->rq_task;
 545
 546         if ((copied = rovr->rq_private_buf.buflen) > repsize)
 547                 copied = repsize;
 548
 549         /* Suck it into the iovec, verify checksum if not done by hw. */
 550         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb))
 551                 goto out_unlock;
 552
 553         /* Something worked... */
 554         dst_confirm(skb->dst);
 555
 556         xprt_adjust_cwnd(task, copied);
 557         xprt_update_rtt(task);
 558         xprt_complete_rqst(task, copied);
 559
 560  out_unlock:
 561         spin_unlock(&xprt->transport_lock);
 562  dropit:
 563         skb_free_datagram(sk, skb);
 564  out:
 565         read_unlock(&sk->sk_callback_lock);
 566 }
 567
 568 static inline size_t xs_tcp_copy_data(skb_reader_t *desc, void *p, size_t len)
 569 {
 570         if (len > desc->count)
 571                 len = desc->count;
 572         if (skb_copy_bits(desc->skb, desc->offset, p, len)) {
 573                 dprintk("RPC:      failed to copy %zu bytes from skb. %zu bytes remain\n",
 574                                 len, desc->count);
 575                 return 0;
 576         }
 577         desc->offset += len;
 578         desc->count -= len;
 579         dprintk("RPC:      copied %zu bytes from skb. %zu bytes remain\n",
 580                         len, desc->count);
 581         return len;
 582 }
 583
 584 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, skb_reader_t *desc)
 585 {
 586         size_t len, used;
 587         char *p;
 588
 589         p = ((char *) &xprt->tcp_recm) + xprt->tcp_offset;
 590         len = sizeof(xprt->tcp_recm) - xprt->tcp_offset;
 591         used = xs_tcp_copy_data(desc, p, len);
 592         xprt->tcp_offset += used;
 593         if (used != len)
 594                 return;
 595
 596         xprt->tcp_reclen = ntohl(xprt->tcp_recm);
 597         if (xprt->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
 598                 xprt->tcp_flags |= XPRT_LAST_FRAG;
 599         else
 600                 xprt->tcp_flags &= ~XPRT_LAST_FRAG;
 601         xprt->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
 602
 603         xprt->tcp_flags &= ~XPRT_COPY_RECM;
 604         xprt->tcp_offset = 0;
 605
 606         /* Sanity check of the record length */
 607         if (unlikely(xprt->tcp_reclen < 4)) {
 608                 dprintk("RPC:      invalid TCP record fragment length\n");
 609                 xprt_disconnect(xprt);
 610                 return;
 611         }
 612         dprintk("RPC:      reading TCP record fragment of length %d\n",
 613                         xprt->tcp_reclen);
 614 }
 615
 616 static void xs_tcp_check_recm(struct rpc_xprt *xprt)
 617 {
 618         dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u, tcp_flags = %lx\n",
 619                         xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen, xprt->tcp_flags);
 620         if (xprt->tcp_offset == xprt->tcp_reclen) {
 621                 xprt->tcp_flags |= XPRT_COPY_RECM;
 622                 xprt->tcp_offset = 0;
 623                 if (xprt->tcp_flags & XPRT_LAST_FRAG) {
 624                         xprt->tcp_flags &= ~XPRT_COPY_DATA;
 625                         xprt->tcp_flags |= XPRT_COPY_XID;
 626                         xprt->tcp_copied = 0;
 627                 }
 628         }
 629 }
 630
 631 static inline void xs_tcp_read_xid(struct rpc_xprt *xprt, skb_reader_t *desc)
 632 {
 633         size_t len, used;
 634         char *p;
 635
 636         len = sizeof(xprt->tcp_xid) - xprt->tcp_offset;
 637         dprintk("RPC:      reading XID (%Zu bytes)\n", len);
 638         p = ((char *) &xprt->tcp_xid) + xprt->tcp_offset;
 639         used = xs_tcp_copy_data(desc, p, len);
 640         xprt->tcp_offset += used;
 641         if (used != len)
 642                 return;
 643         xprt->tcp_flags &= ~XPRT_COPY_XID;
 644         xprt->tcp_flags |= XPRT_COPY_DATA;
 645         xprt->tcp_copied = 4;
 646         dprintk("RPC:      reading reply for XID %08x\n",
 647                                                 ntohl(xprt->tcp_xid));
 648         xs_tcp_check_recm(xprt);
 649 }
 650
 651 static inline void xs_tcp_read_request(struct rpc_xprt *xprt, skb_reader_t *desc)
 652 {
 653         struct rpc_rqst *req;
 654         struct xdr_buf *rcvbuf;
 655         size_t len;
 656         ssize_t r;
 657
 658         /* Find and lock the request corresponding to this xid */
 659         spin_lock(&xprt->transport_lock);
 660         req = xprt_lookup_rqst(xprt, xprt->tcp_xid);
 661         if (!req) {
 662                 xprt->tcp_flags &= ~XPRT_COPY_DATA;
 663                 dprintk("RPC:      XID %08x request not found!\n",
 664                                 ntohl(xprt->tcp_xid));
 665                 spin_unlock(&xprt->transport_lock);
 666                 return;
 667         }
 668
 669         rcvbuf = &req->rq_private_buf;
 670         len = desc->count;
 671         if (len > xprt->tcp_reclen - xprt->tcp_offset) {
 672                 skb_reader_t my_desc;
 673
 674                 len = xprt->tcp_reclen - xprt->tcp_offset;
 675                 memcpy(&my_desc, desc, sizeof(my_desc));
 676                 my_desc.count = len;
 677                 r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
 678                                           &my_desc, xs_tcp_copy_data);
 679                 desc->count -= r;
 680                 desc->offset += r;
 681         } else
 682                 r = xdr_partial_copy_from_skb(rcvbuf, xprt->tcp_copied,
 683                                           desc, xs_tcp_copy_data);
 684
 685         if (r > 0) {
 686                 xprt->tcp_copied += r;
 687                 xprt->tcp_offset += r;
 688         }
 689         if (r != len) {
 690                 /* Error when copying to the receive buffer,
 691                  * usually because we weren't able to allocate
 692                  * additional buffer pages. All we can do now
 693                  * is turn off XPRT_COPY_DATA, so the request
 694                  * will not receive any additional updates,
 695                  * and time out.
 696                  * Any remaining data from this record will
 697                  * be discarded.
 698                  */
 699                 xprt->tcp_flags &= ~XPRT_COPY_DATA;
 700                 dprintk("RPC:      XID %08x truncated request\n",
 701                                 ntohl(xprt->tcp_xid));
 702                 dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
 703                                 xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
 704                 goto out;
 705         }
 706
 707         dprintk("RPC:      XID %08x read %Zd bytes\n",
 708                         ntohl(xprt->tcp_xid), r);
 709         dprintk("RPC:      xprt = %p, tcp_copied = %lu, tcp_offset = %u, tcp_reclen = %u\n",
 710                         xprt, xprt->tcp_copied, xprt->tcp_offset, xprt->tcp_reclen);
 711
 712         if (xprt->tcp_copied == req->rq_private_buf.buflen)
 713                 xprt->tcp_flags &= ~XPRT_COPY_DATA;
 714         else if (xprt->tcp_offset == xprt->tcp_reclen) {
 715                 if (xprt->tcp_flags & XPRT_LAST_FRAG)
 716                         xprt->tcp_flags &= ~XPRT_COPY_DATA;
 717         }
 718
 719 out:
 720         if (!(xprt->tcp_flags & XPRT_COPY_DATA))
 721                 xprt_complete_rqst(req->rq_task, xprt->tcp_copied);
 722         spin_unlock(&xprt->transport_lock);
 723         xs_tcp_check_recm(xprt);
 724 }
 725
 726 static inline void xs_tcp_read_discard(struct rpc_xprt *xprt, skb_reader_t *desc)
 727 {
 728         size_t len;
 729
 730         len = xprt->tcp_reclen - xprt->tcp_offset;
 731         if (len > desc->count)
 732                 len = desc->count;
 733         desc->count -= len;
 734         desc->offset += len;
 735         xprt->tcp_offset += len;
 736         dprintk("RPC:      discarded %Zu bytes\n", len);
 737         xs_tcp_check_recm(xprt);
 738 }
 739
 740 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
 741 {
 742         struct rpc_xprt *xprt = rd_desc->arg.data;
 743         skb_reader_t desc = {
 744                 .skb    = skb,
 745                 .offset = offset,
 746                 .count  = len,
 747                 .csum   = 0
 748         };
 749
 750         dprintk("RPC:      xs_tcp_data_recv started\n");
 751         do {
 752                 /* Read in a new fragment marker if necessary */
 753                 /* Can we ever really expect to get completely empty fragments? */
 754                 if (xprt->tcp_flags & XPRT_COPY_RECM) {
 755                         xs_tcp_read_fraghdr(xprt, &desc);
 756                         continue;
 757                 }
 758                 /* Read in the xid if necessary */
 759                 if (xprt->tcp_flags & XPRT_COPY_XID) {
 760                         xs_tcp_read_xid(xprt, &desc);
 761                         continue;
 762                 }
 763                 /* Read in the request data */
 764                 if (xprt->tcp_flags & XPRT_COPY_DATA) {
 765                         xs_tcp_read_request(xprt, &desc);
 766                         continue;
 767                 }
 768                 /* Skip over any trailing bytes on short reads */
 769                 xs_tcp_read_discard(xprt, &desc);
 770         } while (desc.count);
 771         dprintk("RPC:      xs_tcp_data_recv done\n");
 772         return len - desc.count;
 773 }
 774
 775 /**
 776  * xs_tcp_data_ready - "data ready" callback for TCP sockets
 777  * @sk: socket with data to read
 778  * @bytes: how much data to read
 779  *
 780  */
 781 static void xs_tcp_data_ready(struct sock *sk, int bytes)
 782 {
 783         struct rpc_xprt *xprt;
 784         read_descriptor_t rd_desc;
 785
 786         read_lock(&sk->sk_callback_lock);
 787         dprintk("RPC:      xs_tcp_data_ready...\n");
 788         if (!(xprt = xprt_from_sock(sk)))
 789                 goto out;
 790         if (xprt->shutdown)
 791                 goto out;
 792
 793         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
 794         rd_desc.arg.data = xprt;
 795         rd_desc.count = 65536;
 796         tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
 797 out:
 798         read_unlock(&sk->sk_callback_lock);
 799 }
 800
 801 /**
 802  * xs_tcp_state_change - callback to handle TCP socket state changes
 803  * @sk: socket whose state has changed
 804  *
 805  */
 806 static void xs_tcp_state_change(struct sock *sk)
 807 {
 808         struct rpc_xprt *xprt;
 809
 810         read_lock(&sk->sk_callback_lock);
 811         if (!(xprt = xprt_from_sock(sk)))
 812                 goto out;
 813         dprintk("RPC:      xs_tcp_state_change client %p...\n", xprt);
 814         dprintk("RPC:      state %x conn %d dead %d zapped %d\n",
 815                                 sk->sk_state, xprt_connected(xprt),
 816                                 sock_flag(sk, SOCK_DEAD),
 817                                 sock_flag(sk, SOCK_ZAPPED));
 818
 819         switch (sk->sk_state) {
 820         case TCP_ESTABLISHED:
 821                 spin_lock_bh(&xprt->transport_lock);
 822                 if (!xprt_test_and_set_connected(xprt)) {
 823                         /* Reset TCP record info */
 824                         xprt->tcp_offset = 0;
 825                         xprt->tcp_reclen = 0;
 826                         xprt->tcp_copied = 0;
 827                         xprt->tcp_flags = XPRT_COPY_RECM | XPRT_COPY_XID;
 828                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
 829                         xprt_wake_pending_tasks(xprt, 0);
 830                 }
 831                 spin_unlock_bh(&xprt->transport_lock);
 832                 break;
 833         case TCP_SYN_SENT:
 834         case TCP_SYN_RECV:
 835                 break;
 836         case TCP_CLOSE_WAIT:
 837                 /* Try to schedule an autoclose RPC calls */
 838                 set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 839                 if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
 840                         schedule_work(&xprt->task_cleanup);
 841         default:
 842                 xprt_disconnect(xprt);
 843         }
 844  out:
 845         read_unlock(&sk->sk_callback_lock);
 846 }
 847
 848 /**
 849  * xs_udp_write_space - callback invoked when socket buffer space
 850  *                             becomes available
 851  * @sk: socket whose state has changed
 852  *
 853  * Called when more output buffer space is available for this socket.
 854  * We try not to wake our writers until they can make "significant"
 855  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
 856  * with a bunch of small requests.
 857  */
 858 static void xs_udp_write_space(struct sock *sk)
 859 {
 860         read_lock(&sk->sk_callback_lock);
 861
 862         /* from net/core/sock.c:sock_def_write_space */
 863         if (sock_writeable(sk)) {
 864                 struct socket *sock;
 865                 struct rpc_xprt *xprt;
 866
 867                 if (unlikely(!(sock = sk->sk_socket)))
 868                         goto out;
 869                 if (unlikely(!(xprt = xprt_from_sock(sk))))
 870                         goto out;
 871                 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
 872                         goto out;
 873
 874                 xprt_write_space(xprt);
 875         }
 876
 877  out:
 878         read_unlock(&sk->sk_callback_lock);
 879 }
 880
 881 /**
 882  * xs_tcp_write_space - callback invoked when socket buffer space
 883  *                             becomes available
 884  * @sk: socket whose state has changed
 885  *
 886  * Called when more output buffer space is available for this socket.
 887  * We try not to wake our writers until they can make "significant"
 888  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
 889  * with a bunch of small requests.
 890  */
 891 static void xs_tcp_write_space(struct sock *sk)
 892 {
 893         read_lock(&sk->sk_callback_lock);
 894
 895         /* from net/core/stream.c:sk_stream_write_space */
 896         if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
 897                 struct socket *sock;
 898                 struct rpc_xprt *xprt;
 899
 900                 if (unlikely(!(sock = sk->sk_socket)))
 901                         goto out;
 902                 if (unlikely(!(xprt = xprt_from_sock(sk))))
 903                         goto out;
 904                 if (unlikely(!test_and_clear_bit(SOCK_NOSPACE, &sock->flags)))
 905                         goto out;
 906
 907                 xprt_write_space(xprt);
 908         }
 909
 910  out:
 911         read_unlock(&sk->sk_callback_lock);
 912 }
 913
 914 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
 915 {
 916         struct sock *sk = xprt->inet;
 917
 918         if (xprt->rcvsize) {
 919                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 920                 sk->sk_rcvbuf = xprt->rcvsize * xprt->max_reqs *  2;
 921         }
 922         if (xprt->sndsize) {
 923                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 924                 sk->sk_sndbuf = xprt->sndsize * xprt->max_reqs * 2;
 925                 sk->sk_write_space(sk);
 926         }
 927 }
 928
 929 /**
 930  * xs_udp_set_buffer_size - set send and receive limits
 931  * @xprt: generic transport
 932  * @sndsize: requested size of send buffer, in bytes
 933  * @rcvsize: requested size of receive buffer, in bytes
 934  *
 935  * Set socket send and receive buffer size limits.
 936  */
 937 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
 938 {
 939         xprt->sndsize = 0;
 940         if (sndsize)
 941                 xprt->sndsize = sndsize + 1024;
 942         xprt->rcvsize = 0;
 943         if (rcvsize)
 944                 xprt->rcvsize = rcvsize + 1024;
 945
 946         xs_udp_do_set_buffer_size(xprt);
 947 }
 948
 949 /**
 950  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
 951  * @task: task that timed out
 952  *
 953  * Adjust the congestion window after a retransmit timeout has occurred.
 954  */
 955 static void xs_udp_timer(struct rpc_task *task)
 956 {
 957         xprt_adjust_cwnd(task, -ETIMEDOUT);
 958 }
 959
 960 static unsigned short xs_get_random_port(void)
 961 {
 962         unsigned short range = xprt_max_resvport - xprt_min_resvport;
 963         unsigned short rand = (unsigned short) net_random() % range;
 964         return rand + xprt_min_resvport;
 965 }
 966
 967 /**
 968  * xs_set_port - reset the port number in the remote endpoint address
 969  * @xprt: generic transport
 970  * @port: new port number
 971  *
 972  */
 973 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
 974 {
 975         dprintk("RPC:      setting port for xprt %p to %u\n", xprt, port);
 976         xprt->addr.sin_port = htons(port);
 977 }
 978
 979 static int xs_bindresvport(struct rpc_xprt *xprt, struct socket *sock)
 980 {
 981         struct sockaddr_in myaddr = {
 982                 .sin_family = AF_INET,
 983         };
 984         int err;
 985         unsigned short port = xprt->port;
 986
 987         do {
 988                 myaddr.sin_port = htons(port);
 989                 err = sock->ops->bind(sock, (struct sockaddr *) &myaddr,
 990                                                 sizeof(myaddr));
 991                 if (err == 0) {
 992                         xprt->port = port;
 993                         dprintk("RPC:      xs_bindresvport bound to port %u\n",
 994                                         port);
 995                         return 0;
 996                 }
 997                 if (port <= xprt_min_resvport)
 998                         port = xprt_max_resvport;
 999                 else
1000                         port--;
1001         } while (err == -EADDRINUSE && port != xprt->port);
1002
1003         dprintk("RPC:      can't bind to reserved port (%d).\n", -err);
1004         return err;
1005 }
1006
1007 /**
1008  * xs_udp_connect_worker - set up a UDP socket
1009  * @args: RPC transport to connect
1010  *
1011  * Invoked by a work queue tasklet.
1012  */
1013 static void xs_udp_connect_worker(void *args)
1014 {
1015         struct rpc_xprt *xprt = (struct rpc_xprt *) args;
1016         struct socket *sock = xprt->sock;
1017         int err, status = -EIO;
1018
1019         if (xprt->shutdown || xprt->addr.sin_port == 0)
1020                 goto out;
1021
1022         dprintk("RPC:      xs_udp_connect_worker for xprt %p\n", xprt);
1023
1024         /* Start by resetting any existing state */
1025         xs_close(xprt);
1026
1027         if ((err = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock)) < 0) {
1028                 dprintk("RPC:      can't create UDP transport socket (%d).\n", -err);
1029                 goto out;
1030         }
1031
1032         if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) {
1033                 sock_release(sock);
1034                 goto out;
1035         }
1036
1037         if (!xprt->inet) {
1038                 struct sock *sk = sock->sk;
1039
1040                 write_lock_bh(&sk->sk_callback_lock);
1041
1042                 sk->sk_user_data = xprt;
1043                 xprt->old_data_ready = sk->sk_data_ready;
1044                 xprt->old_state_change = sk->sk_state_change;
1045                 xprt->old_write_space = sk->sk_write_space;
1046                 sk->sk_data_ready = xs_udp_data_ready;
1047                 sk->sk_write_space = xs_udp_write_space;
1048                 sk->sk_no_check = UDP_CSUM_NORCV;
1049                 sk->sk_allocation = GFP_ATOMIC;
1050
1051                 xprt_set_connected(xprt);
1052
1053                 /* Reset to new socket */
1054                 xprt->sock = sock;
1055                 xprt->inet = sk;
1056
1057                 write_unlock_bh(&sk->sk_callback_lock);
1058         }
1059         xs_udp_do_set_buffer_size(xprt);
1060         status = 0;
1061 out:
1062         xprt_wake_pending_tasks(xprt, status);
1063         xprt_clear_connecting(xprt);
1064 }
1065
1066 /*
1067  * We need to preserve the port number so the reply cache on the server can
1068  * find our cached RPC replies when we get around to reconnecting.
1069  */
1070 static void xs_tcp_reuse_connection(struct rpc_xprt *xprt)
1071 {
1072         int result;
1073         struct socket *sock = xprt->sock;
1074         struct sockaddr any;
1075
1076         dprintk("RPC:      disconnecting xprt %p to reuse port\n", xprt);
1077
1078         /*
1079          * Disconnect the transport socket by doing a connect operation
1080          * with AF_UNSPEC.  This should return immediately...
1081          */
1082         memset(&any, 0, sizeof(any));
1083         any.sa_family = AF_UNSPEC;
1084         result = sock->ops->connect(sock, &any, sizeof(any), 0);
1085         if (result)
1086                 dprintk("RPC:      AF_UNSPEC connect return code %d\n",
1087                                 result);
1088 }
1089
1090 /**
1091  * xs_tcp_connect_worker - connect a TCP socket to a remote endpoint
1092  * @args: RPC transport to connect
1093  *
1094  * Invoked by a work queue tasklet.
1095  */
1096 static void xs_tcp_connect_worker(void *args)
1097 {
1098         struct rpc_xprt *xprt = (struct rpc_xprt *)args;
1099         struct socket *sock = xprt->sock;
1100         int err, status = -EIO;
1101
1102         if (xprt->shutdown || xprt->addr.sin_port == 0)
1103                 goto out;
1104
1105         dprintk("RPC:      xs_tcp_connect_worker for xprt %p\n", xprt);
1106
1107         if (!xprt->sock) {
1108                 /* start from scratch */
1109                 if ((err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock)) < 0) {
1110                         dprintk("RPC:      can't create TCP transport socket (%d).\n", -err);
1111                         goto out;
1112                 }
1113
1114                 if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) {
1115                         sock_release(sock);
1116                         goto out;
1117                 }
1118         } else
1119                 /* "close" the socket, preserving the local port */
1120                 xs_tcp_reuse_connection(xprt);
1121
1122         if (!xprt->inet) {
1123                 struct sock *sk = sock->sk;
1124
1125                 write_lock_bh(&sk->sk_callback_lock);
1126
1127                 sk->sk_user_data = xprt;
1128                 xprt->old_data_ready = sk->sk_data_ready;
1129                 xprt->old_state_change = sk->sk_state_change;
1130                 xprt->old_write_space = sk->sk_write_space;
1131                 sk->sk_data_ready = xs_tcp_data_ready;
1132                 sk->sk_state_change = xs_tcp_state_change;
1133                 sk->sk_write_space = xs_tcp_write_space;
1134                 sk->sk_allocation = GFP_ATOMIC;
1135
1136                 /* socket options */
1137                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1138                 sock_reset_flag(sk, SOCK_LINGER);
1139                 tcp_sk(sk)->linger2 = 0;
1140                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1141
1142                 xprt_clear_connected(xprt);
1143
1144                 /* Reset to new socket */
1145                 xprt->sock = sock;
1146                 xprt->inet = sk;
1147
1148                 write_unlock_bh(&sk->sk_callback_lock);
1149         }
1150
1151         /* Tell the socket layer to start connecting... */
1152         xprt->stat.connect_count++;
1153         xprt->stat.connect_start = jiffies;
1154         status = sock->ops->connect(sock, (struct sockaddr *) &xprt->addr,
1155                         sizeof(xprt->addr), O_NONBLOCK);
1156         dprintk("RPC: %p  connect status %d connected %d sock state %d\n",
1157                         xprt, -status, xprt_connected(xprt), sock->sk->sk_state);
1158         if (status < 0) {
1159                 switch (status) {
1160                         case -EINPROGRESS:
1161                         case -EALREADY:
1162                                 goto out_clear;
1163                         case -ECONNREFUSED:
1164                         case -ECONNRESET:
1165                                 /* retry with existing socket, after a delay */
1166                                 break;
1167                         default:
1168                                 /* get rid of existing socket, and retry */
1169                                 xs_close(xprt);
1170                                 break;
1171                 }
1172         }
1173 out:
1174         xprt_wake_pending_tasks(xprt, status);
1175 out_clear:
1176         xprt_clear_connecting(xprt);
1177 }
1178
1179 /**
1180  * xs_connect - connect a socket to a remote endpoint
1181  * @task: address of RPC task that manages state of connect request
1182  *
1183  * TCP: If the remote end dropped the connection, delay reconnecting.
1184  *
1185  * UDP socket connects are synchronous, but we use a work queue anyway
1186  * to guarantee that even unprivileged user processes can set up a
1187  * socket on a privileged port.
1188  *
1189  * If a UDP socket connect fails, the delay behavior here prevents
1190  * retry floods (hard mounts).
1191  */
1192 static void xs_connect(struct rpc_task *task)
1193 {
1194         struct rpc_xprt *xprt = task->tk_xprt;
1195
1196         if (xprt_test_and_set_connecting(xprt))
1197                 return;
1198
1199         if (xprt->sock != NULL) {
1200                 dprintk("RPC:      xs_connect delayed xprt %p for %lu seconds\n",
1201                                 xprt, xprt->reestablish_timeout / HZ);
1202                 schedule_delayed_work(&xprt->connect_worker,
1203                                         xprt->reestablish_timeout);
1204                 xprt->reestablish_timeout <<= 1;
1205                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
1206                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
1207         } else {
1208                 dprintk("RPC:      xs_connect scheduled xprt %p\n", xprt);
1209                 schedule_work(&xprt->connect_worker);
1210
1211                 /* flush_scheduled_work can sleep... */
1212                 if (!RPC_IS_ASYNC(task))
1213                         flush_scheduled_work();
1214         }
1215 }
1216
1217 /**
1218  * xs_udp_print_stats - display UDP socket-specifc stats
1219  * @xprt: rpc_xprt struct containing statistics
1220  * @seq: output file
1221  *
1222  */
1223 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1224 {
1225         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1226                         xprt->port,
1227                         xprt->stat.bind_count,
1228                         xprt->stat.sends,
1229                         xprt->stat.recvs,
1230                         xprt->stat.bad_xids,
1231                         xprt->stat.req_u,
1232                         xprt->stat.bklog_u);
1233 }
1234
1235 /**
1236  * xs_tcp_print_stats - display TCP socket-specifc stats
1237  * @xprt: rpc_xprt struct containing statistics
1238  * @seq: output file
1239  *
1240  */
1241 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1242 {
1243         long idle_time = 0;
1244
1245         if (xprt_connected(xprt))
1246                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
1247
1248         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1249                         xprt->port,
1250                         xprt->stat.bind_count,
1251                         xprt->stat.connect_count,
1252                         xprt->stat.connect_time,
1253                         idle_time,
1254                         xprt->stat.sends,
1255                         xprt->stat.recvs,
1256                         xprt->stat.bad_xids,
1257                         xprt->stat.req_u,
1258                         xprt->stat.bklog_u);
1259 }
1260
1261 static struct rpc_xprt_ops xs_udp_ops = {
1262         .set_buffer_size        = xs_udp_set_buffer_size,
1263         .reserve_xprt           = xprt_reserve_xprt_cong,
1264         .release_xprt           = xprt_release_xprt_cong,
1265         .set_port               = xs_set_port,
1266         .connect                = xs_connect,
1267         .buf_alloc              = rpc_malloc,
1268         .buf_free               = rpc_free,
1269         .send_request           = xs_udp_send_request,
1270         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
1271         .timer                  = xs_udp_timer,
1272         .release_request        = xprt_release_rqst_cong,
1273         .close                  = xs_close,
1274         .destroy                = xs_destroy,
1275         .print_stats            = xs_udp_print_stats,
1276 };
1277
1278 static struct rpc_xprt_ops xs_tcp_ops = {
1279         .reserve_xprt           = xprt_reserve_xprt,
1280         .release_xprt           = xs_tcp_release_xprt,
1281         .set_port               = xs_set_port,
1282         .connect                = xs_connect,
1283         .buf_alloc              = rpc_malloc,
1284         .buf_free               = rpc_free,
1285         .send_request           = xs_tcp_send_request,
1286         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
1287         .close                  = xs_close,
1288         .destroy                = xs_destroy,
1289         .print_stats            = xs_tcp_print_stats,
1290 };
1291
1292 /**
1293  * xs_setup_udp - Set up transport to use a UDP socket
1294  * @xprt: transport to set up
1295  * @to:   timeout parameters
1296  *
1297  */
1298 int xs_setup_udp(struct rpc_xprt *xprt, struct rpc_timeout *to)
1299 {
1300         size_t slot_table_size;
1301
1302         dprintk("RPC:      setting up udp-ipv4 transport...\n");
1303
1304         xprt->max_reqs = xprt_udp_slot_table_entries;
1305         slot_table_size = xprt->max_reqs * sizeof(xprt->slot[0]);
1306         xprt->slot = kzalloc(slot_table_size, GFP_KERNEL);
1307         if (xprt->slot == NULL)
1308                 return -ENOMEM;
1309
1310         xprt->prot = IPPROTO_UDP;
1311         xprt->port = xs_get_random_port();
1312         xprt->tsh_size = 0;
1313         xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0;
1314         /* XXX: header size can vary due to auth type, IPv6, etc. */
1315         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
1316
1317         INIT_WORK(&xprt->connect_worker, xs_udp_connect_worker, xprt);
1318         xprt->bind_timeout = XS_BIND_TO;
1319         xprt->connect_timeout = XS_UDP_CONN_TO;
1320         xprt->reestablish_timeout = XS_UDP_REEST_TO;
1321         xprt->idle_timeout = XS_IDLE_DISC_TO;
1322
1323         xprt->ops = &xs_udp_ops;
1324
1325         if (to)
1326                 xprt->timeout = *to;
1327         else
1328                 xprt_set_timeout(&xprt->timeout, 5, 5 * HZ);
1329
1330         return 0;
1331 }
1332
1333 /**
1334  * xs_setup_tcp - Set up transport to use a TCP socket
1335  * @xprt: transport to set up
1336  * @to: timeout parameters
1337  *
1338  */
1339 int xs_setup_tcp(struct rpc_xprt *xprt, struct rpc_timeout *to)
1340 {
1341         size_t slot_table_size;
1342
1343         dprintk("RPC:      setting up tcp-ipv4 transport...\n");
1344
1345         xprt->max_reqs = xprt_tcp_slot_table_entries;
1346         slot_table_size = xprt->max_reqs * sizeof(xprt->slot[0]);
1347         xprt->slot = kzalloc(slot_table_size, GFP_KERNEL);
1348         if (xprt->slot == NULL)
1349                 return -ENOMEM;
1350
1351         xprt->prot = IPPROTO_TCP;
1352         xprt->port = xs_get_random_port();
1353         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
1354         xprt->resvport = capable(CAP_NET_BIND_SERVICE) ? 1 : 0;
1355         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
1356
1357         INIT_WORK(&xprt->connect_worker, xs_tcp_connect_worker, xprt);
1358         xprt->bind_timeout = XS_BIND_TO;
1359         xprt->connect_timeout = XS_TCP_CONN_TO;
1360         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1361         xprt->idle_timeout = XS_IDLE_DISC_TO;
1362
1363         xprt->ops = &xs_tcp_ops;
1364
1365         if (to)
1366                 xprt->timeout = *to;
1367         else
1368                 xprt_set_timeout(&xprt->timeout, 2, 60 * HZ);
1369
1370         return 0;
1371 }