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
   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  */
  51 unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  52 unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  53
  54 unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  55 unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  56
  57 #define XS_TCP_LINGER_TO        (15U * HZ)
  58 static 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
  71 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  72 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  73 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  74 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  75
  76 static 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  */
  82 static 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
 129 static 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
 176 static 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
 194 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 195 {
 196         /* NOP */
 197 }
 198 #endif
 199
 200 struct 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
 259 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 260 {
 261         return (struct sockaddr *) &xprt->addr;
 262 }
 263
 264 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 265 {
 266         return (struct sockaddr_in *) &xprt->addr;
 267 }
 268
 269 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 270 {
 271         return (struct sockaddr_in6 *) &xprt->addr;
 272 }
 273
 274 static 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
 299 static 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
 311 static 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
 321 static 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
 329 static 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
 345 static 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
 362 static 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  */
 402 static 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);
 441 out:
 442         if (sent == 0)
 443                 return err;
 444         if (err > 0)
 445                 sent += err;
 446         return sent;
 447 }
 448
 449 static 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  */
 462 static 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  */
 509 static 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  */
 568 static 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
 577 static 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  */
 598 static 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  */
 671 static 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);
 685 out_release:
 686         xprt_release_xprt(xprt, task);
 687 }
 688
 689 static 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
 697 static 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
 705 static 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  */
 737 static 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
 754 static 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  */
 767 static 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
 781 static 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  */
 792 static 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(&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(&sk->sk_callback_lock);
 855 }
 856
 857 static 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
 890 static 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
 903 static 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
 925 static 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
 969 static 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  */
1049 static 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  */
1085 static 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
1124 static 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
1135 static 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  */
1146 static 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
1163 static 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
1177 static 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  */
1223 static 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(&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);
1249 out:
1250         read_unlock(&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  */
1258 static 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
1271 static 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
1284 static 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  */
1299 static void xs_tcp_state_change(struct sock *sk)
1300 {
1301         struct rpc_xprt *xprt;
1302
1303         read_lock(&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_bh(&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_bh(&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(&sk->sk_callback_lock);
1368 }
1369
1370 /**
1371  * xs_error_report - callback mainly for catching socket errors
1372  * @sk: socket
1373  */
1374 static void xs_error_report(struct sock *sk)
1375 {
1376         struct rpc_xprt *xprt;
1377
1378         read_lock(&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);
1385 out:
1386         read_unlock(&sk->sk_callback_lock);
1387 }
1388
1389 static 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  */
1416 static void xs_udp_write_space(struct sock *sk)
1417 {
1418         read_lock(&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(&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  */
1437 static void xs_tcp_write_space(struct sock *sk)
1438 {
1439         read_lock(&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(&sk->sk_callback_lock);
1446 }
1447
1448 static 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  */
1472 static 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  */
1492 static void xs_udp_timer(struct rpc_task *task)
1493 {
1494         xprt_adjust_cwnd(task, -ETIMEDOUT);
1495 }
1496
1497 static 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  */
1510 static 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
1518 static 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
1527 static 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 }
1537 static 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 == PF_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
1574 static struct lock_class_key xs_key[2];
1575 static struct lock_class_key xs_slock_key[2];
1576
1577 static 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
1586 static 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
1595 static inline void xs_reclassify_socket(int family, struct socket *sock)
1596 {
1597         if (family == PF_INET)
1598                 xs_reclassify_socket4(sock);
1599         else
1600                 xs_reclassify_socket6(sock);
1601 }
1602 #else
1603 static inline void xs_reclassify_socket4(struct socket *sock)
1604 {
1605 }
1606
1607 static inline void xs_reclassify_socket6(struct socket *sock)
1608 {
1609 }
1610
1611 static inline void xs_reclassify_socket(int family, struct socket *sock)
1612 {
1613 }
1614 #endif
1615
1616 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1617                 struct sock_xprt *transport, int family, int type, int protocol)
1618 {
1619         struct socket *sock;
1620         int err;
1621
1622         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1623         if (err < 0) {
1624                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1625                                 protocol, -err);
1626                 goto out;
1627         }
1628         transport->srcaddr.ss_family = family;
1629         xs_reclassify_socket(family, sock);
1630
1631         if (xs_bind(transport, sock)) {
1632                 sock_release(sock);
1633                 goto out;
1634         }
1635
1636         return sock;
1637 out:
1638         return ERR_PTR(err);
1639 }
1640
1641 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1642 {
1643         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1644
1645         if (!transport->inet) {
1646                 struct sock *sk = sock->sk;
1647
1648                 write_lock_bh(&sk->sk_callback_lock);
1649
1650                 xs_save_old_callbacks(transport, sk);
1651
1652                 sk->sk_user_data = xprt;
1653                 sk->sk_data_ready = xs_udp_data_ready;
1654                 sk->sk_write_space = xs_udp_write_space;
1655                 sk->sk_error_report = xs_error_report;
1656                 sk->sk_no_check = UDP_CSUM_NORCV;
1657                 sk->sk_allocation = GFP_ATOMIC;
1658
1659                 xprt_set_connected(xprt);
1660
1661                 /* Reset to new socket */
1662                 transport->sock = sock;
1663                 transport->inet = sk;
1664
1665                 write_unlock_bh(&sk->sk_callback_lock);
1666         }
1667         xs_udp_do_set_buffer_size(xprt);
1668 }
1669
1670 static void xs_udp_setup_socket(struct work_struct *work)
1671 {
1672         struct sock_xprt *transport =
1673                 container_of(work, struct sock_xprt, connect_worker.work);
1674         struct rpc_xprt *xprt = &transport->xprt;
1675         struct socket *sock = transport->sock;
1676         int status = -EIO;
1677
1678         if (xprt->shutdown)
1679                 goto out;
1680
1681         /* Start by resetting any existing state */
1682         xs_reset_transport(transport);
1683         sock = xs_create_sock(xprt, transport,
1684                         xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
1685         if (IS_ERR(sock))
1686                 goto out;
1687
1688         dprintk("RPC:       worker connecting xprt %p via %s to "
1689                                 "%s (port %s)\n", xprt,
1690                         xprt->address_strings[RPC_DISPLAY_PROTO],
1691                         xprt->address_strings[RPC_DISPLAY_ADDR],
1692                         xprt->address_strings[RPC_DISPLAY_PORT]);
1693
1694         xs_udp_finish_connecting(xprt, sock);
1695         status = 0;
1696 out:
1697         xprt_clear_connecting(xprt);
1698         xprt_wake_pending_tasks(xprt, status);
1699 }
1700
1701 /*
1702  * We need to preserve the port number so the reply cache on the server can
1703  * find our cached RPC replies when we get around to reconnecting.
1704  */
1705 static void xs_abort_connection(struct sock_xprt *transport)
1706 {
1707         int result;
1708         struct sockaddr any;
1709
1710         dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
1711
1712         /*
1713          * Disconnect the transport socket by doing a connect operation
1714          * with AF_UNSPEC.  This should return immediately...
1715          */
1716         memset(&any, 0, sizeof(any));
1717         any.sa_family = AF_UNSPEC;
1718         result = kernel_connect(transport->sock, &any, sizeof(any), 0);
1719         if (!result)
1720                 xs_sock_mark_closed(&transport->xprt);
1721         else
1722                 dprintk("RPC:       AF_UNSPEC connect return code %d\n",
1723                                 result);
1724 }
1725
1726 static void xs_tcp_reuse_connection(struct sock_xprt *transport)
1727 {
1728         unsigned int state = transport->inet->sk_state;
1729
1730         if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
1731                 /* we don't need to abort the connection if the socket
1732                  * hasn't undergone a shutdown
1733                  */
1734                 if (transport->inet->sk_shutdown == 0)
1735                         return;
1736                 dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
1737                                 __func__, transport->inet->sk_shutdown);
1738         }
1739         if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
1740                 /* we don't need to abort the connection if the socket
1741                  * hasn't undergone a shutdown
1742                  */
1743                 if (transport->inet->sk_shutdown == 0)
1744                         return;
1745                 dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
1746                                 "sk_shutdown set to %d\n",
1747                                 __func__, transport->inet->sk_shutdown);
1748         }
1749         xs_abort_connection(transport);
1750 }
1751
1752 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1753 {
1754         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1755
1756         if (!transport->inet) {
1757                 struct sock *sk = sock->sk;
1758
1759                 write_lock_bh(&sk->sk_callback_lock);
1760
1761                 xs_save_old_callbacks(transport, sk);
1762
1763                 sk->sk_user_data = xprt;
1764                 sk->sk_data_ready = xs_tcp_data_ready;
1765                 sk->sk_state_change = xs_tcp_state_change;
1766                 sk->sk_write_space = xs_tcp_write_space;
1767                 sk->sk_error_report = xs_error_report;
1768                 sk->sk_allocation = GFP_ATOMIC;
1769
1770                 /* socket options */
1771                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1772                 sock_reset_flag(sk, SOCK_LINGER);
1773                 tcp_sk(sk)->linger2 = 0;
1774                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1775
1776                 xprt_clear_connected(xprt);
1777
1778                 /* Reset to new socket */
1779                 transport->sock = sock;
1780                 transport->inet = sk;
1781
1782                 write_unlock_bh(&sk->sk_callback_lock);
1783         }
1784
1785         if (!xprt_bound(xprt))
1786                 return -ENOTCONN;
1787
1788         /* Tell the socket layer to start connecting... */
1789         xprt->stat.connect_count++;
1790         xprt->stat.connect_start = jiffies;
1791         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
1792 }
1793
1794 /**
1795  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
1796  * @xprt: RPC transport to connect
1797  * @transport: socket transport to connect
1798  * @create_sock: function to create a socket of the correct type
1799  *
1800  * Invoked by a work queue tasklet.
1801  */
1802 static void xs_tcp_setup_socket(struct work_struct *work)
1803 {
1804         struct sock_xprt *transport =
1805                 container_of(work, struct sock_xprt, connect_worker.work);
1806         struct socket *sock = transport->sock;
1807         struct rpc_xprt *xprt = &transport->xprt;
1808         int status = -EIO;
1809
1810         if (xprt->shutdown)
1811                 goto out;
1812
1813         if (!sock) {
1814                 clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1815                 sock = xs_create_sock(xprt, transport,
1816                                 xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
1817                 if (IS_ERR(sock)) {
1818                         status = PTR_ERR(sock);
1819                         goto out;
1820                 }
1821         } else {
1822                 int abort_and_exit;
1823
1824                 abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
1825                                 &xprt->state);
1826                 /* "close" the socket, preserving the local port */
1827                 xs_tcp_reuse_connection(transport);
1828
1829                 if (abort_and_exit)
1830                         goto out_eagain;
1831         }
1832
1833         dprintk("RPC:       worker connecting xprt %p via %s to "
1834                                 "%s (port %s)\n", xprt,
1835                         xprt->address_strings[RPC_DISPLAY_PROTO],
1836                         xprt->address_strings[RPC_DISPLAY_ADDR],
1837                         xprt->address_strings[RPC_DISPLAY_PORT]);
1838
1839         status = xs_tcp_finish_connecting(xprt, sock);
1840         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1841                         xprt, -status, xprt_connected(xprt),
1842                         sock->sk->sk_state);
1843         switch (status) {
1844         default:
1845                 printk("%s: connect returned unhandled error %d\n",
1846                         __func__, status);
1847         case -EADDRNOTAVAIL:
1848                 /* We're probably in TIME_WAIT. Get rid of existing socket,
1849                  * and retry
1850                  */
1851                 set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1852                 xprt_force_disconnect(xprt);
1853                 break;
1854         case -ECONNREFUSED:
1855         case -ECONNRESET:
1856         case -ENETUNREACH:
1857                 /* retry with existing socket, after a delay */
1858         case 0:
1859         case -EINPROGRESS:
1860         case -EALREADY:
1861                 xprt_clear_connecting(xprt);
1862                 return;
1863         case -EINVAL:
1864                 /* Happens, for instance, if the user specified a link
1865                  * local IPv6 address without a scope-id.
1866                  */
1867                 goto out;
1868         }
1869 out_eagain:
1870         status = -EAGAIN;
1871 out:
1872         xprt_clear_connecting(xprt);
1873         xprt_wake_pending_tasks(xprt, status);
1874 }
1875
1876 /**
1877  * xs_connect - connect a socket to a remote endpoint
1878  * @task: address of RPC task that manages state of connect request
1879  *
1880  * TCP: If the remote end dropped the connection, delay reconnecting.
1881  *
1882  * UDP socket connects are synchronous, but we use a work queue anyway
1883  * to guarantee that even unprivileged user processes can set up a
1884  * socket on a privileged port.
1885  *
1886  * If a UDP socket connect fails, the delay behavior here prevents
1887  * retry floods (hard mounts).
1888  */
1889 static void xs_connect(struct rpc_task *task)
1890 {
1891         struct rpc_xprt *xprt = task->tk_xprt;
1892         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1893
1894         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
1895                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
1896                                 "seconds\n",
1897                                 xprt, xprt->reestablish_timeout / HZ);
1898                 queue_delayed_work(rpciod_workqueue,
1899                                    &transport->connect_worker,
1900                                    xprt->reestablish_timeout);
1901                 xprt->reestablish_timeout <<= 1;
1902                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1903                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1904                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
1905                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
1906         } else {
1907                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
1908                 queue_delayed_work(rpciod_workqueue,
1909                                    &transport->connect_worker, 0);
1910         }
1911 }
1912
1913 /**
1914  * xs_udp_print_stats - display UDP socket-specifc stats
1915  * @xprt: rpc_xprt struct containing statistics
1916  * @seq: output file
1917  *
1918  */
1919 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1920 {
1921         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1922
1923         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1924                         transport->srcport,
1925                         xprt->stat.bind_count,
1926                         xprt->stat.sends,
1927                         xprt->stat.recvs,
1928                         xprt->stat.bad_xids,
1929                         xprt->stat.req_u,
1930                         xprt->stat.bklog_u);
1931 }
1932
1933 /**
1934  * xs_tcp_print_stats - display TCP socket-specifc stats
1935  * @xprt: rpc_xprt struct containing statistics
1936  * @seq: output file
1937  *
1938  */
1939 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1940 {
1941         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1942         long idle_time = 0;
1943
1944         if (xprt_connected(xprt))
1945                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
1946
1947         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1948                         transport->srcport,
1949                         xprt->stat.bind_count,
1950                         xprt->stat.connect_count,
1951                         xprt->stat.connect_time,
1952                         idle_time,
1953                         xprt->stat.sends,
1954                         xprt->stat.recvs,
1955                         xprt->stat.bad_xids,
1956                         xprt->stat.req_u,
1957                         xprt->stat.bklog_u);
1958 }
1959
1960 /*
1961  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
1962  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
1963  * to use the server side send routines.
1964  */
1965 static void *bc_malloc(struct rpc_task *task, size_t size)
1966 {
1967         struct page *page;
1968         struct rpc_buffer *buf;
1969
1970         BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
1971         page = alloc_page(GFP_KERNEL);
1972
1973         if (!page)
1974                 return NULL;
1975
1976         buf = page_address(page);
1977         buf->len = PAGE_SIZE;
1978
1979         return buf->data;
1980 }
1981
1982 /*
1983  * Free the space allocated in the bc_alloc routine
1984  */
1985 static void bc_free(void *buffer)
1986 {
1987         struct rpc_buffer *buf;
1988
1989         if (!buffer)
1990                 return;
1991
1992         buf = container_of(buffer, struct rpc_buffer, data);
1993         free_page((unsigned long)buf);
1994 }
1995
1996 /*
1997  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
1998  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
1999  */
2000 static int bc_sendto(struct rpc_rqst *req)
2001 {
2002         int len;
2003         struct xdr_buf *xbufp = &req->rq_snd_buf;
2004         struct rpc_xprt *xprt = req->rq_xprt;
2005         struct sock_xprt *transport =
2006                                 container_of(xprt, struct sock_xprt, xprt);
2007         struct socket *sock = transport->sock;
2008         unsigned long headoff;
2009         unsigned long tailoff;
2010
2011         /*
2012          * Set up the rpc header and record marker stuff
2013          */
2014         xs_encode_tcp_record_marker(xbufp);
2015
2016         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2017         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2018         len = svc_send_common(sock, xbufp,
2019                               virt_to_page(xbufp->head[0].iov_base), headoff,
2020                               xbufp->tail[0].iov_base, tailoff);
2021
2022         if (len != xbufp->len) {
2023                 printk(KERN_NOTICE "Error sending entire callback!\n");
2024                 len = -EAGAIN;
2025         }
2026
2027         return len;
2028 }
2029
2030 /*
2031  * The send routine. Borrows from svc_send
2032  */
2033 static int bc_send_request(struct rpc_task *task)
2034 {
2035         struct rpc_rqst *req = task->tk_rqstp;
2036         struct svc_xprt *xprt;
2037         struct svc_sock         *svsk;
2038         u32                     len;
2039
2040         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2041         /*
2042          * Get the server socket associated with this callback xprt
2043          */
2044         xprt = req->rq_xprt->bc_xprt;
2045         svsk = container_of(xprt, struct svc_sock, sk_xprt);
2046
2047         /*
2048          * Grab the mutex to serialize data as the connection is shared
2049          * with the fore channel
2050          */
2051         if (!mutex_trylock(&xprt->xpt_mutex)) {
2052                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2053                 if (!mutex_trylock(&xprt->xpt_mutex))
2054                         return -EAGAIN;
2055                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2056         }
2057         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2058                 len = -ENOTCONN;
2059         else
2060                 len = bc_sendto(req);
2061         mutex_unlock(&xprt->xpt_mutex);
2062
2063         if (len > 0)
2064                 len = 0;
2065
2066         return len;
2067 }
2068
2069 /*
2070  * The close routine. Since this is client initiated, we do nothing
2071  */
2072
2073 static void bc_close(struct rpc_xprt *xprt)
2074 {
2075 }
2076
2077 /*
2078  * The xprt destroy routine. Again, because this connection is client
2079  * initiated, we do nothing
2080  */
2081
2082 static void bc_destroy(struct rpc_xprt *xprt)
2083 {
2084 }
2085
2086 static struct rpc_xprt_ops xs_udp_ops = {
2087         .set_buffer_size        = xs_udp_set_buffer_size,
2088         .reserve_xprt           = xprt_reserve_xprt_cong,
2089         .release_xprt           = xprt_release_xprt_cong,
2090         .rpcbind                = rpcb_getport_async,
2091         .set_port               = xs_set_port,
2092         .connect                = xs_connect,
2093         .buf_alloc              = rpc_malloc,
2094         .buf_free               = rpc_free,
2095         .send_request           = xs_udp_send_request,
2096         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2097         .timer                  = xs_udp_timer,
2098         .release_request        = xprt_release_rqst_cong,
2099         .close                  = xs_close,
2100         .destroy                = xs_destroy,
2101         .print_stats            = xs_udp_print_stats,
2102 };
2103
2104 static struct rpc_xprt_ops xs_tcp_ops = {
2105         .reserve_xprt           = xprt_reserve_xprt,
2106         .release_xprt           = xs_tcp_release_xprt,
2107         .rpcbind                = rpcb_getport_async,
2108         .set_port               = xs_set_port,
2109         .connect                = xs_connect,
2110         .buf_alloc              = rpc_malloc,
2111         .buf_free               = rpc_free,
2112         .send_request           = xs_tcp_send_request,
2113         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2114         .close                  = xs_tcp_close,
2115         .destroy                = xs_destroy,
2116         .print_stats            = xs_tcp_print_stats,
2117 };
2118
2119 /*
2120  * The rpc_xprt_ops for the server backchannel
2121  */
2122
2123 static struct rpc_xprt_ops bc_tcp_ops = {
2124         .reserve_xprt           = xprt_reserve_xprt,
2125         .release_xprt           = xprt_release_xprt,
2126         .buf_alloc              = bc_malloc,
2127         .buf_free               = bc_free,
2128         .send_request           = bc_send_request,
2129         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2130         .close                  = bc_close,
2131         .destroy                = bc_destroy,
2132         .print_stats            = xs_tcp_print_stats,
2133 };
2134
2135 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2136                                       unsigned int slot_table_size)
2137 {
2138         struct rpc_xprt *xprt;
2139         struct sock_xprt *new;
2140
2141         if (args->addrlen > sizeof(xprt->addr)) {
2142                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2143                 return ERR_PTR(-EBADF);
2144         }
2145
2146         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size);
2147         if (xprt == NULL) {
2148                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2149                                 "rpc_xprt\n");
2150                 return ERR_PTR(-ENOMEM);
2151         }
2152
2153         new = container_of(xprt, struct sock_xprt, xprt);
2154         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2155         xprt->addrlen = args->addrlen;
2156         if (args->srcaddr)
2157                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2158
2159         return xprt;
2160 }
2161
2162 static const struct rpc_timeout xs_udp_default_timeout = {
2163         .to_initval = 5 * HZ,
2164         .to_maxval = 30 * HZ,
2165         .to_increment = 5 * HZ,
2166         .to_retries = 5,
2167 };
2168
2169 /**
2170  * xs_setup_udp - Set up transport to use a UDP socket
2171  * @args: rpc transport creation arguments
2172  *
2173  */
2174 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2175 {
2176         struct sockaddr *addr = args->dstaddr;
2177         struct rpc_xprt *xprt;
2178         struct sock_xprt *transport;
2179         struct rpc_xprt *ret;
2180
2181         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
2182         if (IS_ERR(xprt))
2183                 return xprt;
2184         transport = container_of(xprt, struct sock_xprt, xprt);
2185
2186         xprt->prot = IPPROTO_UDP;
2187         xprt->tsh_size = 0;
2188         /* XXX: header size can vary due to auth type, IPv6, etc. */
2189         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2190
2191         xprt->bind_timeout = XS_BIND_TO;
2192         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2193         xprt->idle_timeout = XS_IDLE_DISC_TO;
2194
2195         xprt->ops = &xs_udp_ops;
2196
2197         xprt->timeout = &xs_udp_default_timeout;
2198
2199         switch (addr->sa_family) {
2200         case AF_INET:
2201                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2202                         xprt_set_bound(xprt);
2203
2204                 INIT_DELAYED_WORK(&transport->connect_worker,
2205                                         xs_udp_setup_socket);
2206                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2207                 break;
2208         case AF_INET6:
2209                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2210                         xprt_set_bound(xprt);
2211
2212                 INIT_DELAYED_WORK(&transport->connect_worker,
2213                                         xs_udp_setup_socket);
2214                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2215                 break;
2216         default:
2217                 ret = ERR_PTR(-EAFNOSUPPORT);
2218                 goto out_err;
2219         }
2220
2221         if (xprt_bound(xprt))
2222                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2223                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2224                                 xprt->address_strings[RPC_DISPLAY_PORT],
2225                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2226         else
2227                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2228                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2229                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2230
2231         if (try_module_get(THIS_MODULE))
2232                 return xprt;
2233         ret = ERR_PTR(-EINVAL);
2234 out_err:
2235         xprt_free(xprt);
2236         return ret;
2237 }
2238
2239 static const struct rpc_timeout xs_tcp_default_timeout = {
2240         .to_initval = 60 * HZ,
2241         .to_maxval = 60 * HZ,
2242         .to_retries = 2,
2243 };
2244
2245 /**
2246  * xs_setup_tcp - Set up transport to use a TCP socket
2247  * @args: rpc transport creation arguments
2248  *
2249  */
2250 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2251 {
2252         struct sockaddr *addr = args->dstaddr;
2253         struct rpc_xprt *xprt;
2254         struct sock_xprt *transport;
2255         struct rpc_xprt *ret;
2256
2257         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2258         if (IS_ERR(xprt))
2259                 return xprt;
2260         transport = container_of(xprt, struct sock_xprt, xprt);
2261
2262         xprt->prot = IPPROTO_TCP;
2263         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2264         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2265
2266         xprt->bind_timeout = XS_BIND_TO;
2267         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2268         xprt->idle_timeout = XS_IDLE_DISC_TO;
2269
2270         xprt->ops = &xs_tcp_ops;
2271         xprt->timeout = &xs_tcp_default_timeout;
2272
2273         switch (addr->sa_family) {
2274         case AF_INET:
2275                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2276                         xprt_set_bound(xprt);
2277
2278                 INIT_DELAYED_WORK(&transport->connect_worker,
2279                                         xs_tcp_setup_socket);
2280                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2281                 break;
2282         case AF_INET6:
2283                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2284                         xprt_set_bound(xprt);
2285
2286                 INIT_DELAYED_WORK(&transport->connect_worker,
2287                                         xs_tcp_setup_socket);
2288                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2289                 break;
2290         default:
2291                 ret = ERR_PTR(-EAFNOSUPPORT);
2292                 goto out_err;
2293         }
2294
2295         if (xprt_bound(xprt))
2296                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2297                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2298                                 xprt->address_strings[RPC_DISPLAY_PORT],
2299                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2300         else
2301                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2302                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2303                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2304
2305
2306         if (try_module_get(THIS_MODULE))
2307                 return xprt;
2308         ret = ERR_PTR(-EINVAL);
2309 out_err:
2310         xprt_free(xprt);
2311         return ret;
2312 }
2313
2314 /**
2315  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2316  * @args: rpc transport creation arguments
2317  *
2318  */
2319 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2320 {
2321         struct sockaddr *addr = args->dstaddr;
2322         struct rpc_xprt *xprt;
2323         struct sock_xprt *transport;
2324         struct svc_sock *bc_sock;
2325         struct rpc_xprt *ret;
2326
2327         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2328         if (IS_ERR(xprt))
2329                 return xprt;
2330         transport = container_of(xprt, struct sock_xprt, xprt);
2331
2332         xprt->prot = IPPROTO_TCP;
2333         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2334         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2335         xprt->timeout = &xs_tcp_default_timeout;
2336
2337         /* backchannel */
2338         xprt_set_bound(xprt);
2339         xprt->bind_timeout = 0;
2340         xprt->reestablish_timeout = 0;
2341         xprt->idle_timeout = 0;
2342
2343         /*
2344          * The backchannel uses the same socket connection as the
2345          * forechannel
2346          */
2347         xprt->bc_xprt = args->bc_xprt;
2348         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2349         bc_sock->sk_bc_xprt = xprt;
2350         transport->sock = bc_sock->sk_sock;
2351         transport->inet = bc_sock->sk_sk;
2352
2353         xprt->ops = &bc_tcp_ops;
2354
2355         switch (addr->sa_family) {
2356         case AF_INET:
2357                 xs_format_peer_addresses(xprt, "tcp",
2358                                          RPCBIND_NETID_TCP);
2359                 break;
2360         case AF_INET6:
2361                 xs_format_peer_addresses(xprt, "tcp",
2362                                    RPCBIND_NETID_TCP6);
2363                 break;
2364         default:
2365                 ret = ERR_PTR(-EAFNOSUPPORT);
2366                 goto out_err;
2367         }
2368
2369         if (xprt_bound(xprt))
2370                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2371                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2372                                 xprt->address_strings[RPC_DISPLAY_PORT],
2373                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2374         else
2375                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2376                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2377                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2378
2379         /*
2380          * Since we don't want connections for the backchannel, we set
2381          * the xprt status to connected
2382          */
2383         xprt_set_connected(xprt);
2384
2385
2386         if (try_module_get(THIS_MODULE))
2387                 return xprt;
2388         ret = ERR_PTR(-EINVAL);
2389 out_err:
2390         xprt_free(xprt);
2391         return ret;
2392 }
2393
2394 static struct xprt_class        xs_udp_transport = {
2395         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2396         .name           = "udp",
2397         .owner          = THIS_MODULE,
2398         .ident          = XPRT_TRANSPORT_UDP,
2399         .setup          = xs_setup_udp,
2400 };
2401
2402 static struct xprt_class        xs_tcp_transport = {
2403         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
2404         .name           = "tcp",
2405         .owner          = THIS_MODULE,
2406         .ident          = XPRT_TRANSPORT_TCP,
2407         .setup          = xs_setup_tcp,
2408 };
2409
2410 static struct xprt_class        xs_bc_tcp_transport = {
2411         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2412         .name           = "tcp NFSv4.1 backchannel",
2413         .owner          = THIS_MODULE,
2414         .ident          = XPRT_TRANSPORT_BC_TCP,
2415         .setup          = xs_setup_bc_tcp,
2416 };
2417
2418 /**
2419  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
2420  *
2421  */
2422 int init_socket_xprt(void)
2423 {
2424 #ifdef RPC_DEBUG
2425         if (!sunrpc_table_header)
2426                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
2427 #endif
2428
2429         xprt_register_transport(&xs_udp_transport);
2430         xprt_register_transport(&xs_tcp_transport);
2431         xprt_register_transport(&xs_bc_tcp_transport);
2432
2433         return 0;
2434 }
2435
2436 /**
2437  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
2438  *
2439  */
2440 void cleanup_socket_xprt(void)
2441 {
2442 #ifdef RPC_DEBUG
2443         if (sunrpc_table_header) {
2444                 unregister_sysctl_table(sunrpc_table_header);
2445                 sunrpc_table_header = NULL;
2446         }
2447 #endif
2448
2449         xprt_unregister_transport(&xs_udp_transport);
2450         xprt_unregister_transport(&xs_tcp_transport);
2451         xprt_unregister_transport(&xs_bc_tcp_transport);
2452 }
2453
2454 static int param_set_uint_minmax(const char *val,
2455                 const struct kernel_param *kp,
2456                 unsigned int min, unsigned int max)
2457 {
2458         unsigned long num;
2459         int ret;
2460
2461         if (!val)
2462                 return -EINVAL;
2463         ret = strict_strtoul(val, 0, &num);
2464         if (ret == -EINVAL || num < min || num > max)
2465                 return -EINVAL;
2466         *((unsigned int *)kp->arg) = num;
2467         return 0;
2468 }
2469
2470 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2471 {
2472         return param_set_uint_minmax(val, kp,
2473                         RPC_MIN_RESVPORT,
2474                         RPC_MAX_RESVPORT);
2475 }
2476
2477 static struct kernel_param_ops param_ops_portnr = {
2478         .set = param_set_portnr,
2479         .get = param_get_uint,
2480 };
2481
2482 #define param_check_portnr(name, p) \
2483         __param_check(name, p, unsigned int);
2484
2485 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
2486 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
2487
2488 static int param_set_slot_table_size(const char *val,
2489                                      const struct kernel_param *kp)
2490 {
2491         return param_set_uint_minmax(val, kp,
2492                         RPC_MIN_SLOT_TABLE,
2493                         RPC_MAX_SLOT_TABLE);
2494 }
2495
2496 static struct kernel_param_ops param_ops_slot_table_size = {
2497         .set = param_set_slot_table_size,
2498         .get = param_get_uint,
2499 };
2500
2501 #define param_check_slot_table_size(name, p) \
2502         __param_check(name, p, unsigned int);
2503
2504 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
2505                    slot_table_size, 0644);
2506 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
2507                    slot_table_size, 0644);
2508