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  * Construct a stream transport record marker in @buf.
 500  */
 501 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 502 {
 503         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 504         rpc_fraghdr *base = buf->head[0].iov_base;
 505         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 506 }
 507
 508 /**
 509  * xs_udp_send_request - write an RPC request to a UDP socket
 510  * @task: address of RPC task that manages the state of an RPC request
 511  *
 512  * Return values:
 513  *        0:    The request has been sent
 514  *   EAGAIN:    The socket was blocked, please call again later to
 515  *              complete the request
 516  * ENOTCONN:    Caller needs to invoke connect logic then call again
 517  *    other:    Some other error occurred, the request was not sent
 518  */
 519 static int xs_udp_send_request(struct rpc_task *task)
 520 {
 521         struct rpc_rqst *req = task->tk_rqstp;
 522         struct rpc_xprt *xprt = req->rq_xprt;
 523         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 524         struct xdr_buf *xdr = &req->rq_snd_buf;
 525         int status;
 526
 527         xs_pktdump("packet data:",
 528                                 req->rq_svec->iov_base,
 529                                 req->rq_svec->iov_len);
 530
 531         if (!xprt_bound(xprt))
 532                 return -ENOTCONN;
 533         status = xs_sendpages(transport->sock,
 534                               xs_addr(xprt),
 535                               xprt->addrlen, xdr,
 536                               req->rq_bytes_sent);
 537
 538         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 539                         xdr->len - req->rq_bytes_sent, status);
 540
 541         if (status >= 0) {
 542                 req->rq_xmit_bytes_sent += status;
 543                 if (status >= req->rq_slen)
 544                         return 0;
 545                 /* Still some bytes left; set up for a retry later. */
 546                 status = -EAGAIN;
 547         }
 548
 549         switch (status) {
 550         case -ENOTSOCK:
 551                 status = -ENOTCONN;
 552                 /* Should we call xs_close() here? */
 553                 break;
 554         case -EAGAIN:
 555                 status = xs_nospace(task);
 556                 break;
 557         default:
 558                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 559                         -status);
 560         case -ENETUNREACH:
 561         case -EPIPE:
 562         case -ECONNREFUSED:
 563                 /* When the server has died, an ICMP port unreachable message
 564                  * prompts ECONNREFUSED. */
 565                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 566         }
 567
 568         return status;
 569 }
 570
 571 /**
 572  * xs_tcp_shutdown - gracefully shut down a TCP socket
 573  * @xprt: transport
 574  *
 575  * Initiates a graceful shutdown of the TCP socket by calling the
 576  * equivalent of shutdown(SHUT_WR);
 577  */
 578 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 579 {
 580         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 581         struct socket *sock = transport->sock;
 582
 583         if (sock != NULL)
 584                 kernel_sock_shutdown(sock, SHUT_WR);
 585 }
 586
 587 /**
 588  * xs_tcp_send_request - write an RPC request to a TCP socket
 589  * @task: address of RPC task that manages the state of an RPC request
 590  *
 591  * Return values:
 592  *        0:    The request has been sent
 593  *   EAGAIN:    The socket was blocked, please call again later to
 594  *              complete the request
 595  * ENOTCONN:    Caller needs to invoke connect logic then call again
 596  *    other:    Some other error occurred, the request was not sent
 597  *
 598  * XXX: In the case of soft timeouts, should we eventually give up
 599  *      if sendmsg is not able to make progress?
 600  */
 601 static int xs_tcp_send_request(struct rpc_task *task)
 602 {
 603         struct rpc_rqst *req = task->tk_rqstp;
 604         struct rpc_xprt *xprt = req->rq_xprt;
 605         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 606         struct xdr_buf *xdr = &req->rq_snd_buf;
 607         int status;
 608
 609         xs_encode_stream_record_marker(&req->rq_snd_buf);
 610
 611         xs_pktdump("packet data:",
 612                                 req->rq_svec->iov_base,
 613                                 req->rq_svec->iov_len);
 614
 615         /* Continue transmitting the packet/record. We must be careful
 616          * to cope with writespace callbacks arriving _after_ we have
 617          * called sendmsg(). */
 618         while (1) {
 619                 status = xs_sendpages(transport->sock,
 620                                         NULL, 0, xdr, req->rq_bytes_sent);
 621
 622                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 623                                 xdr->len - req->rq_bytes_sent, status);
 624
 625                 if (unlikely(status < 0))
 626                         break;
 627
 628                 /* If we've sent the entire packet, immediately
 629                  * reset the count of bytes sent. */
 630                 req->rq_bytes_sent += status;
 631                 req->rq_xmit_bytes_sent += status;
 632                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 633                         req->rq_bytes_sent = 0;
 634                         return 0;
 635                 }
 636
 637                 if (status != 0)
 638                         continue;
 639                 status = -EAGAIN;
 640                 break;
 641         }
 642
 643         switch (status) {
 644         case -ENOTSOCK:
 645                 status = -ENOTCONN;
 646                 /* Should we call xs_close() here? */
 647                 break;
 648         case -EAGAIN:
 649                 status = xs_nospace(task);
 650                 break;
 651         default:
 652                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 653                         -status);
 654         case -ECONNRESET:
 655         case -EPIPE:
 656                 xs_tcp_shutdown(xprt);
 657         case -ECONNREFUSED:
 658         case -ENOTCONN:
 659                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 660         }
 661
 662         return status;
 663 }
 664
 665 /**
 666  * xs_tcp_release_xprt - clean up after a tcp transmission
 667  * @xprt: transport
 668  * @task: rpc task
 669  *
 670  * This cleans up if an error causes us to abort the transmission of a request.
 671  * In this case, the socket may need to be reset in order to avoid confusing
 672  * the server.
 673  */
 674 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 675 {
 676         struct rpc_rqst *req;
 677
 678         if (task != xprt->snd_task)
 679                 return;
 680         if (task == NULL)
 681                 goto out_release;
 682         req = task->tk_rqstp;
 683         if (req->rq_bytes_sent == 0)
 684                 goto out_release;
 685         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 686                 goto out_release;
 687         set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
 688 out_release:
 689         xprt_release_xprt(xprt, task);
 690 }
 691
 692 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 693 {
 694         transport->old_data_ready = sk->sk_data_ready;
 695         transport->old_state_change = sk->sk_state_change;
 696         transport->old_write_space = sk->sk_write_space;
 697         transport->old_error_report = sk->sk_error_report;
 698 }
 699
 700 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 701 {
 702         sk->sk_data_ready = transport->old_data_ready;
 703         sk->sk_state_change = transport->old_state_change;
 704         sk->sk_write_space = transport->old_write_space;
 705         sk->sk_error_report = transport->old_error_report;
 706 }
 707
 708 static void xs_reset_transport(struct sock_xprt *transport)
 709 {
 710         struct socket *sock = transport->sock;
 711         struct sock *sk = transport->inet;
 712
 713         if (sk == NULL)
 714                 return;
 715
 716         transport->srcport = 0;
 717
 718         write_lock_bh(&sk->sk_callback_lock);
 719         transport->inet = NULL;
 720         transport->sock = NULL;
 721
 722         sk->sk_user_data = NULL;
 723
 724         xs_restore_old_callbacks(transport, sk);
 725         write_unlock_bh(&sk->sk_callback_lock);
 726
 727         sk->sk_no_check = 0;
 728
 729         sock_release(sock);
 730 }
 731
 732 /**
 733  * xs_close - close a socket
 734  * @xprt: transport
 735  *
 736  * This is used when all requests are complete; ie, no DRC state remains
 737  * on the server we want to save.
 738  *
 739  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 740  * xs_reset_transport() zeroing the socket from underneath a writer.
 741  */
 742 static void xs_close(struct rpc_xprt *xprt)
 743 {
 744         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 745
 746         dprintk("RPC:       xs_close xprt %p\n", xprt);
 747
 748         xs_reset_transport(transport);
 749         xprt->reestablish_timeout = 0;
 750
 751         smp_mb__before_clear_bit();
 752         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 753         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 754         clear_bit(XPRT_CLOSING, &xprt->state);
 755         smp_mb__after_clear_bit();
 756         xprt_disconnect_done(xprt);
 757 }
 758
 759 static void xs_tcp_close(struct rpc_xprt *xprt)
 760 {
 761         if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 762                 xs_close(xprt);
 763         else
 764                 xs_tcp_shutdown(xprt);
 765 }
 766
 767 /**
 768  * xs_destroy - prepare to shutdown a transport
 769  * @xprt: doomed transport
 770  *
 771  */
 772 static void xs_destroy(struct rpc_xprt *xprt)
 773 {
 774         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 775
 776         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 777
 778         cancel_delayed_work_sync(&transport->connect_worker);
 779
 780         xs_close(xprt);
 781         xs_free_peer_addresses(xprt);
 782         xprt_free(xprt);
 783         module_put(THIS_MODULE);
 784 }
 785
 786 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 787 {
 788         return (struct rpc_xprt *) sk->sk_user_data;
 789 }
 790
 791 /**
 792  * xs_udp_data_ready - "data ready" callback for UDP sockets
 793  * @sk: socket with data to read
 794  * @len: how much data to read
 795  *
 796  */
 797 static void xs_udp_data_ready(struct sock *sk, int len)
 798 {
 799         struct rpc_task *task;
 800         struct rpc_xprt *xprt;
 801         struct rpc_rqst *rovr;
 802         struct sk_buff *skb;
 803         int err, repsize, copied;
 804         u32 _xid;
 805         __be32 *xp;
 806
 807         read_lock_bh(&sk->sk_callback_lock);
 808         dprintk("RPC:       xs_udp_data_ready...\n");
 809         if (!(xprt = xprt_from_sock(sk)))
 810                 goto out;
 811
 812         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 813                 goto out;
 814
 815         if (xprt->shutdown)
 816                 goto dropit;
 817
 818         repsize = skb->len - sizeof(struct udphdr);
 819         if (repsize < 4) {
 820                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
 821                 goto dropit;
 822         }
 823
 824         /* Copy the XID from the skb... */
 825         xp = skb_header_pointer(skb, sizeof(struct udphdr),
 826                                 sizeof(_xid), &_xid);
 827         if (xp == NULL)
 828                 goto dropit;
 829
 830         /* Look up and lock the request corresponding to the given XID */
 831         spin_lock(&xprt->transport_lock);
 832         rovr = xprt_lookup_rqst(xprt, *xp);
 833         if (!rovr)
 834                 goto out_unlock;
 835         task = rovr->rq_task;
 836
 837         if ((copied = rovr->rq_private_buf.buflen) > repsize)
 838                 copied = repsize;
 839
 840         /* Suck it into the iovec, verify checksum if not done by hw. */
 841         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 842                 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
 843                 goto out_unlock;
 844         }
 845
 846         UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
 847
 848         /* Something worked... */
 849         dst_confirm(skb_dst(skb));
 850
 851         xprt_adjust_cwnd(task, copied);
 852         xprt_complete_rqst(task, copied);
 853
 854  out_unlock:
 855         spin_unlock(&xprt->transport_lock);
 856  dropit:
 857         skb_free_datagram(sk, skb);
 858  out:
 859         read_unlock_bh(&sk->sk_callback_lock);
 860 }
 861
 862 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
 863 {
 864         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 865         size_t len, used;
 866         char *p;
 867
 868         p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
 869         len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
 870         used = xdr_skb_read_bits(desc, p, len);
 871         transport->tcp_offset += used;
 872         if (used != len)
 873                 return;
 874
 875         transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
 876         if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
 877                 transport->tcp_flags |= TCP_RCV_LAST_FRAG;
 878         else
 879                 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
 880         transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
 881
 882         transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
 883         transport->tcp_offset = 0;
 884
 885         /* Sanity check of the record length */
 886         if (unlikely(transport->tcp_reclen < 8)) {
 887                 dprintk("RPC:       invalid TCP record fragment length\n");
 888                 xprt_force_disconnect(xprt);
 889                 return;
 890         }
 891         dprintk("RPC:       reading TCP record fragment of length %d\n",
 892                         transport->tcp_reclen);
 893 }
 894
 895 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
 896 {
 897         if (transport->tcp_offset == transport->tcp_reclen) {
 898                 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
 899                 transport->tcp_offset = 0;
 900                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
 901                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
 902                         transport->tcp_flags |= TCP_RCV_COPY_XID;
 903                         transport->tcp_copied = 0;
 904                 }
 905         }
 906 }
 907
 908 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
 909 {
 910         size_t len, used;
 911         char *p;
 912
 913         len = sizeof(transport->tcp_xid) - transport->tcp_offset;
 914         dprintk("RPC:       reading XID (%Zu bytes)\n", len);
 915         p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
 916         used = xdr_skb_read_bits(desc, p, len);
 917         transport->tcp_offset += used;
 918         if (used != len)
 919                 return;
 920         transport->tcp_flags &= ~TCP_RCV_COPY_XID;
 921         transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
 922         transport->tcp_copied = 4;
 923         dprintk("RPC:       reading %s XID %08x\n",
 924                         (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
 925                                                               : "request with",
 926                         ntohl(transport->tcp_xid));
 927         xs_tcp_check_fraghdr(transport);
 928 }
 929
 930 static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
 931                                        struct xdr_skb_reader *desc)
 932 {
 933         size_t len, used;
 934         u32 offset;
 935         char *p;
 936
 937         /*
 938          * We want transport->tcp_offset to be 8 at the end of this routine
 939          * (4 bytes for the xid and 4 bytes for the call/reply flag).
 940          * When this function is called for the first time,
 941          * transport->tcp_offset is 4 (after having already read the xid).
 942          */
 943         offset = transport->tcp_offset - sizeof(transport->tcp_xid);
 944         len = sizeof(transport->tcp_calldir) - offset;
 945         dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
 946         p = ((char *) &transport->tcp_calldir) + offset;
 947         used = xdr_skb_read_bits(desc, p, len);
 948         transport->tcp_offset += used;
 949         if (used != len)
 950                 return;
 951         transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
 952         /*
 953          * We don't yet have the XDR buffer, so we will write the calldir
 954          * out after we get the buffer from the 'struct rpc_rqst'
 955          */
 956         switch (ntohl(transport->tcp_calldir)) {
 957         case RPC_REPLY:
 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         case RPC_CALL:
 963                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
 964                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
 965                 transport->tcp_flags &= ~TCP_RPC_REPLY;
 966                 break;
 967         default:
 968                 dprintk("RPC:       invalid request message type\n");
 969                 xprt_force_disconnect(&transport->xprt);
 970         }
 971         xs_tcp_check_fraghdr(transport);
 972 }
 973
 974 static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
 975                                      struct xdr_skb_reader *desc,
 976                                      struct rpc_rqst *req)
 977 {
 978         struct sock_xprt *transport =
 979                                 container_of(xprt, struct sock_xprt, xprt);
 980         struct xdr_buf *rcvbuf;
 981         size_t len;
 982         ssize_t r;
 983
 984         rcvbuf = &req->rq_private_buf;
 985
 986         if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
 987                 /*
 988                  * Save the RPC direction in the XDR buffer
 989                  */
 990                 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
 991                         &transport->tcp_calldir,
 992                         sizeof(transport->tcp_calldir));
 993                 transport->tcp_copied += sizeof(transport->tcp_calldir);
 994                 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
 995         }
 996
 997         len = desc->count;
 998         if (len > transport->tcp_reclen - transport->tcp_offset) {
 999                 struct xdr_skb_reader my_desc;
1000
1001                 len = transport->tcp_reclen - transport->tcp_offset;
1002                 memcpy(&my_desc, desc, sizeof(my_desc));
1003                 my_desc.count = len;
1004                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1005                                           &my_desc, xdr_skb_read_bits);
1006                 desc->count -= r;
1007                 desc->offset += r;
1008         } else
1009                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1010                                           desc, xdr_skb_read_bits);
1011
1012         if (r > 0) {
1013                 transport->tcp_copied += r;
1014                 transport->tcp_offset += r;
1015         }
1016         if (r != len) {
1017                 /* Error when copying to the receive buffer,
1018                  * usually because we weren't able to allocate
1019                  * additional buffer pages. All we can do now
1020                  * is turn off TCP_RCV_COPY_DATA, so the request
1021                  * will not receive any additional updates,
1022                  * and time out.
1023                  * Any remaining data from this record will
1024                  * be discarded.
1025                  */
1026                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1027                 dprintk("RPC:       XID %08x truncated request\n",
1028                                 ntohl(transport->tcp_xid));
1029                 dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1030                                 "tcp_offset = %u, tcp_reclen = %u\n",
1031                                 xprt, transport->tcp_copied,
1032                                 transport->tcp_offset, transport->tcp_reclen);
1033                 return;
1034         }
1035
1036         dprintk("RPC:       XID %08x read %Zd bytes\n",
1037                         ntohl(transport->tcp_xid), r);
1038         dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1039                         "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1040                         transport->tcp_offset, transport->tcp_reclen);
1041
1042         if (transport->tcp_copied == req->rq_private_buf.buflen)
1043                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1044         else if (transport->tcp_offset == transport->tcp_reclen) {
1045                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1046                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1047         }
1048 }
1049
1050 /*
1051  * Finds the request corresponding to the RPC xid and invokes the common
1052  * tcp read code to read the data.
1053  */
1054 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1055                                     struct xdr_skb_reader *desc)
1056 {
1057         struct sock_xprt *transport =
1058                                 container_of(xprt, struct sock_xprt, xprt);
1059         struct rpc_rqst *req;
1060
1061         dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1062
1063         /* Find and lock the request corresponding to this xid */
1064         spin_lock(&xprt->transport_lock);
1065         req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1066         if (!req) {
1067                 dprintk("RPC:       XID %08x request not found!\n",
1068                                 ntohl(transport->tcp_xid));
1069                 spin_unlock(&xprt->transport_lock);
1070                 return -1;
1071         }
1072
1073         xs_tcp_read_common(xprt, desc, req);
1074
1075         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1076                 xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1077
1078         spin_unlock(&xprt->transport_lock);
1079         return 0;
1080 }
1081
1082 #if defined(CONFIG_NFS_V4_1)
1083 /*
1084  * Obtains an rpc_rqst previously allocated and invokes the common
1085  * tcp read code to read the data.  The result is placed in the callback
1086  * queue.
1087  * If we're unable to obtain the rpc_rqst we schedule the closing of the
1088  * connection and return -1.
1089  */
1090 static inline int xs_tcp_read_callback(struct rpc_xprt *xprt,
1091                                        struct xdr_skb_reader *desc)
1092 {
1093         struct sock_xprt *transport =
1094                                 container_of(xprt, struct sock_xprt, xprt);
1095         struct rpc_rqst *req;
1096
1097         req = xprt_alloc_bc_request(xprt);
1098         if (req == NULL) {
1099                 printk(KERN_WARNING "Callback slot table overflowed\n");
1100                 xprt_force_disconnect(xprt);
1101                 return -1;
1102         }
1103
1104         req->rq_xid = transport->tcp_xid;
1105         dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1106         xs_tcp_read_common(xprt, desc, req);
1107
1108         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) {
1109                 struct svc_serv *bc_serv = xprt->bc_serv;
1110
1111                 /*
1112                  * Add callback request to callback list.  The callback
1113                  * service sleeps on the sv_cb_waitq waiting for new
1114                  * requests.  Wake it up after adding enqueing the
1115                  * request.
1116                  */
1117                 dprintk("RPC:       add callback request to list\n");
1118                 spin_lock(&bc_serv->sv_cb_lock);
1119                 list_add(&req->rq_bc_list, &bc_serv->sv_cb_list);
1120                 spin_unlock(&bc_serv->sv_cb_lock);
1121                 wake_up(&bc_serv->sv_cb_waitq);
1122         }
1123
1124         req->rq_private_buf.len = transport->tcp_copied;
1125
1126         return 0;
1127 }
1128
1129 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1130                                         struct xdr_skb_reader *desc)
1131 {
1132         struct sock_xprt *transport =
1133                                 container_of(xprt, struct sock_xprt, xprt);
1134
1135         return (transport->tcp_flags & TCP_RPC_REPLY) ?
1136                 xs_tcp_read_reply(xprt, desc) :
1137                 xs_tcp_read_callback(xprt, desc);
1138 }
1139 #else
1140 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1141                                         struct xdr_skb_reader *desc)
1142 {
1143         return xs_tcp_read_reply(xprt, desc);
1144 }
1145 #endif /* CONFIG_NFS_V4_1 */
1146
1147 /*
1148  * Read data off the transport.  This can be either an RPC_CALL or an
1149  * RPC_REPLY.  Relay the processing to helper functions.
1150  */
1151 static void xs_tcp_read_data(struct rpc_xprt *xprt,
1152                                     struct xdr_skb_reader *desc)
1153 {
1154         struct sock_xprt *transport =
1155                                 container_of(xprt, struct sock_xprt, xprt);
1156
1157         if (_xs_tcp_read_data(xprt, desc) == 0)
1158                 xs_tcp_check_fraghdr(transport);
1159         else {
1160                 /*
1161                  * The transport_lock protects the request handling.
1162                  * There's no need to hold it to update the tcp_flags.
1163                  */
1164                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1165         }
1166 }
1167
1168 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1169 {
1170         size_t len;
1171
1172         len = transport->tcp_reclen - transport->tcp_offset;
1173         if (len > desc->count)
1174                 len = desc->count;
1175         desc->count -= len;
1176         desc->offset += len;
1177         transport->tcp_offset += len;
1178         dprintk("RPC:       discarded %Zu bytes\n", len);
1179         xs_tcp_check_fraghdr(transport);
1180 }
1181
1182 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1183 {
1184         struct rpc_xprt *xprt = rd_desc->arg.data;
1185         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1186         struct xdr_skb_reader desc = {
1187                 .skb    = skb,
1188                 .offset = offset,
1189                 .count  = len,
1190         };
1191
1192         dprintk("RPC:       xs_tcp_data_recv started\n");
1193         do {
1194                 /* Read in a new fragment marker if necessary */
1195                 /* Can we ever really expect to get completely empty fragments? */
1196                 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1197                         xs_tcp_read_fraghdr(xprt, &desc);
1198                         continue;
1199                 }
1200                 /* Read in the xid if necessary */
1201                 if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1202                         xs_tcp_read_xid(transport, &desc);
1203                         continue;
1204                 }
1205                 /* Read in the call/reply flag */
1206                 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1207                         xs_tcp_read_calldir(transport, &desc);
1208                         continue;
1209                 }
1210                 /* Read in the request data */
1211                 if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1212                         xs_tcp_read_data(xprt, &desc);
1213                         continue;
1214                 }
1215                 /* Skip over any trailing bytes on short reads */
1216                 xs_tcp_read_discard(transport, &desc);
1217         } while (desc.count);
1218         dprintk("RPC:       xs_tcp_data_recv done\n");
1219         return len - desc.count;
1220 }
1221
1222 /**
1223  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1224  * @sk: socket with data to read
1225  * @bytes: how much data to read
1226  *
1227  */
1228 static void xs_tcp_data_ready(struct sock *sk, int bytes)
1229 {
1230         struct rpc_xprt *xprt;
1231         read_descriptor_t rd_desc;
1232         int read;
1233
1234         dprintk("RPC:       xs_tcp_data_ready...\n");
1235
1236         read_lock_bh(&sk->sk_callback_lock);
1237         if (!(xprt = xprt_from_sock(sk)))
1238                 goto out;
1239         if (xprt->shutdown)
1240                 goto out;
1241
1242         /* Any data means we had a useful conversation, so
1243          * the we don't need to delay the next reconnect
1244          */
1245         if (xprt->reestablish_timeout)
1246                 xprt->reestablish_timeout = 0;
1247
1248         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1249         rd_desc.arg.data = xprt;
1250         do {
1251                 rd_desc.count = 65536;
1252                 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1253         } while (read > 0);
1254 out:
1255         read_unlock_bh(&sk->sk_callback_lock);
1256 }
1257
1258 /*
1259  * Do the equivalent of linger/linger2 handling for dealing with
1260  * broken servers that don't close the socket in a timely
1261  * fashion
1262  */
1263 static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1264                 unsigned long timeout)
1265 {
1266         struct sock_xprt *transport;
1267
1268         if (xprt_test_and_set_connecting(xprt))
1269                 return;
1270         set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1271         transport = container_of(xprt, struct sock_xprt, xprt);
1272         queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1273                            timeout);
1274 }
1275
1276 static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1277 {
1278         struct sock_xprt *transport;
1279
1280         transport = container_of(xprt, struct sock_xprt, xprt);
1281
1282         if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1283             !cancel_delayed_work(&transport->connect_worker))
1284                 return;
1285         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1286         xprt_clear_connecting(xprt);
1287 }
1288
1289 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1290 {
1291         smp_mb__before_clear_bit();
1292         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1293         clear_bit(XPRT_CLOSING, &xprt->state);
1294         smp_mb__after_clear_bit();
1295         /* Mark transport as closed and wake up all pending tasks */
1296         xprt_disconnect_done(xprt);
1297 }
1298
1299 /**
1300  * xs_tcp_state_change - callback to handle TCP socket state changes
1301  * @sk: socket whose state has changed
1302  *
1303  */
1304 static void xs_tcp_state_change(struct sock *sk)
1305 {
1306         struct rpc_xprt *xprt;
1307
1308         read_lock_bh(&sk->sk_callback_lock);
1309         if (!(xprt = xprt_from_sock(sk)))
1310                 goto out;
1311         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1312         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1313                         sk->sk_state, xprt_connected(xprt),
1314                         sock_flag(sk, SOCK_DEAD),
1315                         sock_flag(sk, SOCK_ZAPPED),
1316                         sk->sk_shutdown);
1317
1318         switch (sk->sk_state) {
1319         case TCP_ESTABLISHED:
1320                 spin_lock(&xprt->transport_lock);
1321                 if (!xprt_test_and_set_connected(xprt)) {
1322                         struct sock_xprt *transport = container_of(xprt,
1323                                         struct sock_xprt, xprt);
1324
1325                         /* Reset TCP record info */
1326                         transport->tcp_offset = 0;
1327                         transport->tcp_reclen = 0;
1328                         transport->tcp_copied = 0;
1329                         transport->tcp_flags =
1330                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1331
1332                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1333                 }
1334                 spin_unlock(&xprt->transport_lock);
1335                 break;
1336         case TCP_FIN_WAIT1:
1337                 /* The client initiated a shutdown of the socket */
1338                 xprt->connect_cookie++;
1339                 xprt->reestablish_timeout = 0;
1340                 set_bit(XPRT_CLOSING, &xprt->state);
1341                 smp_mb__before_clear_bit();
1342                 clear_bit(XPRT_CONNECTED, &xprt->state);
1343                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1344                 smp_mb__after_clear_bit();
1345                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1346                 break;
1347         case TCP_CLOSE_WAIT:
1348                 /* The server initiated a shutdown of the socket */
1349                 xprt_force_disconnect(xprt);
1350                 xprt->connect_cookie++;
1351         case TCP_CLOSING:
1352                 /*
1353                  * If the server closed down the connection, make sure that
1354                  * we back off before reconnecting
1355                  */
1356                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1357                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1358                 break;
1359         case TCP_LAST_ACK:
1360                 set_bit(XPRT_CLOSING, &xprt->state);
1361                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1362                 smp_mb__before_clear_bit();
1363                 clear_bit(XPRT_CONNECTED, &xprt->state);
1364                 smp_mb__after_clear_bit();
1365                 break;
1366         case TCP_CLOSE:
1367                 xs_tcp_cancel_linger_timeout(xprt);
1368                 xs_sock_mark_closed(xprt);
1369         }
1370  out:
1371         read_unlock_bh(&sk->sk_callback_lock);
1372 }
1373
1374 /**
1375  * xs_error_report - callback mainly for catching socket errors
1376  * @sk: socket
1377  */
1378 static void xs_error_report(struct sock *sk)
1379 {
1380         struct rpc_xprt *xprt;
1381
1382         read_lock_bh(&sk->sk_callback_lock);
1383         if (!(xprt = xprt_from_sock(sk)))
1384                 goto out;
1385         dprintk("RPC:       %s client %p...\n"
1386                         "RPC:       error %d\n",
1387                         __func__, xprt, sk->sk_err);
1388         xprt_wake_pending_tasks(xprt, -EAGAIN);
1389 out:
1390         read_unlock_bh(&sk->sk_callback_lock);
1391 }
1392
1393 static void xs_write_space(struct sock *sk)
1394 {
1395         struct socket *sock;
1396         struct rpc_xprt *xprt;
1397
1398         if (unlikely(!(sock = sk->sk_socket)))
1399                 return;
1400         clear_bit(SOCK_NOSPACE, &sock->flags);
1401
1402         if (unlikely(!(xprt = xprt_from_sock(sk))))
1403                 return;
1404         if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1405                 return;
1406
1407         xprt_write_space(xprt);
1408 }
1409
1410 /**
1411  * xs_udp_write_space - callback invoked when socket buffer space
1412  *                             becomes available
1413  * @sk: socket whose state has changed
1414  *
1415  * Called when more output buffer space is available for this socket.
1416  * We try not to wake our writers until they can make "significant"
1417  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1418  * with a bunch of small requests.
1419  */
1420 static void xs_udp_write_space(struct sock *sk)
1421 {
1422         read_lock_bh(&sk->sk_callback_lock);
1423
1424         /* from net/core/sock.c:sock_def_write_space */
1425         if (sock_writeable(sk))
1426                 xs_write_space(sk);
1427
1428         read_unlock_bh(&sk->sk_callback_lock);
1429 }
1430
1431 /**
1432  * xs_tcp_write_space - callback invoked when socket buffer space
1433  *                             becomes available
1434  * @sk: socket whose state has changed
1435  *
1436  * Called when more output buffer space is available for this socket.
1437  * We try not to wake our writers until they can make "significant"
1438  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1439  * with a bunch of small requests.
1440  */
1441 static void xs_tcp_write_space(struct sock *sk)
1442 {
1443         read_lock_bh(&sk->sk_callback_lock);
1444
1445         /* from net/core/stream.c:sk_stream_write_space */
1446         if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
1447                 xs_write_space(sk);
1448
1449         read_unlock_bh(&sk->sk_callback_lock);
1450 }
1451
1452 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1453 {
1454         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1455         struct sock *sk = transport->inet;
1456
1457         if (transport->rcvsize) {
1458                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1459                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1460         }
1461         if (transport->sndsize) {
1462                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1463                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1464                 sk->sk_write_space(sk);
1465         }
1466 }
1467
1468 /**
1469  * xs_udp_set_buffer_size - set send and receive limits
1470  * @xprt: generic transport
1471  * @sndsize: requested size of send buffer, in bytes
1472  * @rcvsize: requested size of receive buffer, in bytes
1473  *
1474  * Set socket send and receive buffer size limits.
1475  */
1476 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1477 {
1478         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1479
1480         transport->sndsize = 0;
1481         if (sndsize)
1482                 transport->sndsize = sndsize + 1024;
1483         transport->rcvsize = 0;
1484         if (rcvsize)
1485                 transport->rcvsize = rcvsize + 1024;
1486
1487         xs_udp_do_set_buffer_size(xprt);
1488 }
1489
1490 /**
1491  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1492  * @task: task that timed out
1493  *
1494  * Adjust the congestion window after a retransmit timeout has occurred.
1495  */
1496 static void xs_udp_timer(struct rpc_task *task)
1497 {
1498         xprt_adjust_cwnd(task, -ETIMEDOUT);
1499 }
1500
1501 static unsigned short xs_get_random_port(void)
1502 {
1503         unsigned short range = xprt_max_resvport - xprt_min_resvport;
1504         unsigned short rand = (unsigned short) net_random() % range;
1505         return rand + xprt_min_resvport;
1506 }
1507
1508 /**
1509  * xs_set_port - reset the port number in the remote endpoint address
1510  * @xprt: generic transport
1511  * @port: new port number
1512  *
1513  */
1514 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1515 {
1516         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1517
1518         rpc_set_port(xs_addr(xprt), port);
1519         xs_update_peer_port(xprt);
1520 }
1521
1522 static unsigned short xs_get_srcport(struct sock_xprt *transport)
1523 {
1524         unsigned short port = transport->srcport;
1525
1526         if (port == 0 && transport->xprt.resvport)
1527                 port = xs_get_random_port();
1528         return port;
1529 }
1530
1531 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1532 {
1533         if (transport->srcport != 0)
1534                 transport->srcport = 0;
1535         if (!transport->xprt.resvport)
1536                 return 0;
1537         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1538                 return xprt_max_resvport;
1539         return --port;
1540 }
1541 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1542 {
1543         struct sockaddr_storage myaddr;
1544         int err, nloop = 0;
1545         unsigned short port = xs_get_srcport(transport);
1546         unsigned short last;
1547
1548         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1549         do {
1550                 rpc_set_port((struct sockaddr *)&myaddr, port);
1551                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1552                                 transport->xprt.addrlen);
1553                 if (port == 0)
1554                         break;
1555                 if (err == 0) {
1556                         transport->srcport = port;
1557                         break;
1558                 }
1559                 last = port;
1560                 port = xs_next_srcport(transport, port);
1561                 if (port > last)
1562                         nloop++;
1563         } while (err == -EADDRINUSE && nloop != 2);
1564
1565         if (myaddr.ss_family == AF_INET)
1566                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1567                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1568                                 port, err ? "failed" : "ok", err);
1569         else
1570                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1571                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1572                                 port, err ? "failed" : "ok", err);
1573         return err;
1574 }
1575
1576
1577 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1578 static struct lock_class_key xs_key[2];
1579 static struct lock_class_key xs_slock_key[2];
1580
1581 static inline void xs_reclassify_socket4(struct socket *sock)
1582 {
1583         struct sock *sk = sock->sk;
1584
1585         BUG_ON(sock_owned_by_user(sk));
1586         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1587                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1588 }
1589
1590 static inline void xs_reclassify_socket6(struct socket *sock)
1591 {
1592         struct sock *sk = sock->sk;
1593
1594         BUG_ON(sock_owned_by_user(sk));
1595         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1596                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1597 }
1598
1599 static inline void xs_reclassify_socket(int family, struct socket *sock)
1600 {
1601         switch (family) {
1602         case AF_INET:
1603                 xs_reclassify_socket4(sock);
1604                 break;
1605         case AF_INET6:
1606                 xs_reclassify_socket6(sock);
1607                 break;
1608         }
1609 }
1610 #else
1611 static inline void xs_reclassify_socket4(struct socket *sock)
1612 {
1613 }
1614
1615 static inline void xs_reclassify_socket6(struct socket *sock)
1616 {
1617 }
1618
1619 static inline void xs_reclassify_socket(int family, struct socket *sock)
1620 {
1621 }
1622 #endif
1623
1624 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1625                 struct sock_xprt *transport, int family, int type, int protocol)
1626 {
1627         struct socket *sock;
1628         int err;
1629
1630         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1631         if (err < 0) {
1632                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1633                                 protocol, -err);
1634                 goto out;
1635         }
1636         xs_reclassify_socket(family, sock);
1637
1638         err = xs_bind(transport, sock);
1639         if (err) {
1640                 sock_release(sock);
1641                 goto out;
1642         }
1643
1644         return sock;
1645 out:
1646         return ERR_PTR(err);
1647 }
1648
1649 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1650 {
1651         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1652
1653         if (!transport->inet) {
1654                 struct sock *sk = sock->sk;
1655
1656                 write_lock_bh(&sk->sk_callback_lock);
1657
1658                 xs_save_old_callbacks(transport, sk);
1659
1660                 sk->sk_user_data = xprt;
1661                 sk->sk_data_ready = xs_udp_data_ready;
1662                 sk->sk_write_space = xs_udp_write_space;
1663                 sk->sk_error_report = xs_error_report;
1664                 sk->sk_no_check = UDP_CSUM_NORCV;
1665                 sk->sk_allocation = GFP_ATOMIC;
1666
1667                 xprt_set_connected(xprt);
1668
1669                 /* Reset to new socket */
1670                 transport->sock = sock;
1671                 transport->inet = sk;
1672
1673                 write_unlock_bh(&sk->sk_callback_lock);
1674         }
1675         xs_udp_do_set_buffer_size(xprt);
1676 }
1677
1678 static void xs_udp_setup_socket(struct work_struct *work)
1679 {
1680         struct sock_xprt *transport =
1681                 container_of(work, struct sock_xprt, connect_worker.work);
1682         struct rpc_xprt *xprt = &transport->xprt;
1683         struct socket *sock = transport->sock;
1684         int status = -EIO;
1685
1686         if (xprt->shutdown)
1687                 goto out;
1688
1689         /* Start by resetting any existing state */
1690         xs_reset_transport(transport);
1691         sock = xs_create_sock(xprt, transport,
1692                         xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
1693         if (IS_ERR(sock))
1694                 goto out;
1695
1696         dprintk("RPC:       worker connecting xprt %p via %s to "
1697                                 "%s (port %s)\n", xprt,
1698                         xprt->address_strings[RPC_DISPLAY_PROTO],
1699                         xprt->address_strings[RPC_DISPLAY_ADDR],
1700                         xprt->address_strings[RPC_DISPLAY_PORT]);
1701
1702         xs_udp_finish_connecting(xprt, sock);
1703         status = 0;
1704 out:
1705         xprt_clear_connecting(xprt);
1706         xprt_wake_pending_tasks(xprt, status);
1707 }
1708
1709 /*
1710  * We need to preserve the port number so the reply cache on the server can
1711  * find our cached RPC replies when we get around to reconnecting.
1712  */
1713 static void xs_abort_connection(struct sock_xprt *transport)
1714 {
1715         int result;
1716         struct sockaddr any;
1717
1718         dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
1719
1720         /*
1721          * Disconnect the transport socket by doing a connect operation
1722          * with AF_UNSPEC.  This should return immediately...
1723          */
1724         memset(&any, 0, sizeof(any));
1725         any.sa_family = AF_UNSPEC;
1726         result = kernel_connect(transport->sock, &any, sizeof(any), 0);
1727         if (!result)
1728                 xs_sock_mark_closed(&transport->xprt);
1729         else
1730                 dprintk("RPC:       AF_UNSPEC connect return code %d\n",
1731                                 result);
1732 }
1733
1734 static void xs_tcp_reuse_connection(struct sock_xprt *transport)
1735 {
1736         unsigned int state = transport->inet->sk_state;
1737
1738         if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
1739                 /* we don't need to abort the connection if the socket
1740                  * hasn't undergone a shutdown
1741                  */
1742                 if (transport->inet->sk_shutdown == 0)
1743                         return;
1744                 dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
1745                                 __func__, transport->inet->sk_shutdown);
1746         }
1747         if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
1748                 /* we don't need to abort the connection if the socket
1749                  * hasn't undergone a shutdown
1750                  */
1751                 if (transport->inet->sk_shutdown == 0)
1752                         return;
1753                 dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
1754                                 "sk_shutdown set to %d\n",
1755                                 __func__, transport->inet->sk_shutdown);
1756         }
1757         xs_abort_connection(transport);
1758 }
1759
1760 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1761 {
1762         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1763         int ret = -ENOTCONN;
1764
1765         if (!transport->inet) {
1766                 struct sock *sk = sock->sk;
1767
1768                 write_lock_bh(&sk->sk_callback_lock);
1769
1770                 xs_save_old_callbacks(transport, sk);
1771
1772                 sk->sk_user_data = xprt;
1773                 sk->sk_data_ready = xs_tcp_data_ready;
1774                 sk->sk_state_change = xs_tcp_state_change;
1775                 sk->sk_write_space = xs_tcp_write_space;
1776                 sk->sk_error_report = xs_error_report;
1777                 sk->sk_allocation = GFP_ATOMIC;
1778
1779                 /* socket options */
1780                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1781                 sock_reset_flag(sk, SOCK_LINGER);
1782                 tcp_sk(sk)->linger2 = 0;
1783                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1784
1785                 xprt_clear_connected(xprt);
1786
1787                 /* Reset to new socket */
1788                 transport->sock = sock;
1789                 transport->inet = sk;
1790
1791                 write_unlock_bh(&sk->sk_callback_lock);
1792         }
1793
1794         if (!xprt_bound(xprt))
1795                 goto out;
1796
1797         /* Tell the socket layer to start connecting... */
1798         xprt->stat.connect_count++;
1799         xprt->stat.connect_start = jiffies;
1800         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
1801         switch (ret) {
1802         case 0:
1803         case -EINPROGRESS:
1804                 /* SYN_SENT! */
1805                 xprt->connect_cookie++;
1806                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1807                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1808         }
1809 out:
1810         return ret;
1811 }
1812
1813 /**
1814  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
1815  * @xprt: RPC transport to connect
1816  * @transport: socket transport to connect
1817  * @create_sock: function to create a socket of the correct type
1818  *
1819  * Invoked by a work queue tasklet.
1820  */
1821 static void xs_tcp_setup_socket(struct work_struct *work)
1822 {
1823         struct sock_xprt *transport =
1824                 container_of(work, struct sock_xprt, connect_worker.work);
1825         struct socket *sock = transport->sock;
1826         struct rpc_xprt *xprt = &transport->xprt;
1827         int status = -EIO;
1828
1829         if (xprt->shutdown)
1830                 goto out;
1831
1832         if (!sock) {
1833                 clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1834                 sock = xs_create_sock(xprt, transport,
1835                                 xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
1836                 if (IS_ERR(sock)) {
1837                         status = PTR_ERR(sock);
1838                         goto out;
1839                 }
1840         } else {
1841                 int abort_and_exit;
1842
1843                 abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
1844                                 &xprt->state);
1845                 /* "close" the socket, preserving the local port */
1846                 xs_tcp_reuse_connection(transport);
1847
1848                 if (abort_and_exit)
1849                         goto out_eagain;
1850         }
1851
1852         dprintk("RPC:       worker connecting xprt %p via %s to "
1853                                 "%s (port %s)\n", xprt,
1854                         xprt->address_strings[RPC_DISPLAY_PROTO],
1855                         xprt->address_strings[RPC_DISPLAY_ADDR],
1856                         xprt->address_strings[RPC_DISPLAY_PORT]);
1857
1858         status = xs_tcp_finish_connecting(xprt, sock);
1859         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1860                         xprt, -status, xprt_connected(xprt),
1861                         sock->sk->sk_state);
1862         switch (status) {
1863         default:
1864                 printk("%s: connect returned unhandled error %d\n",
1865                         __func__, status);
1866         case -EADDRNOTAVAIL:
1867                 /* We're probably in TIME_WAIT. Get rid of existing socket,
1868                  * and retry
1869                  */
1870                 set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1871                 xprt_force_disconnect(xprt);
1872                 break;
1873         case -ECONNREFUSED:
1874         case -ECONNRESET:
1875         case -ENETUNREACH:
1876                 /* retry with existing socket, after a delay */
1877         case 0:
1878         case -EINPROGRESS:
1879         case -EALREADY:
1880                 xprt_clear_connecting(xprt);
1881                 return;
1882         case -EINVAL:
1883                 /* Happens, for instance, if the user specified a link
1884                  * local IPv6 address without a scope-id.
1885                  */
1886                 goto out;
1887         }
1888 out_eagain:
1889         status = -EAGAIN;
1890 out:
1891         xprt_clear_connecting(xprt);
1892         xprt_wake_pending_tasks(xprt, status);
1893 }
1894
1895 /**
1896  * xs_connect - connect a socket to a remote endpoint
1897  * @task: address of RPC task that manages state of connect request
1898  *
1899  * TCP: If the remote end dropped the connection, delay reconnecting.
1900  *
1901  * UDP socket connects are synchronous, but we use a work queue anyway
1902  * to guarantee that even unprivileged user processes can set up a
1903  * socket on a privileged port.
1904  *
1905  * If a UDP socket connect fails, the delay behavior here prevents
1906  * retry floods (hard mounts).
1907  */
1908 static void xs_connect(struct rpc_task *task)
1909 {
1910         struct rpc_xprt *xprt = task->tk_xprt;
1911         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1912
1913         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
1914                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
1915                                 "seconds\n",
1916                                 xprt, xprt->reestablish_timeout / HZ);
1917                 queue_delayed_work(rpciod_workqueue,
1918                                    &transport->connect_worker,
1919                                    xprt->reestablish_timeout);
1920                 xprt->reestablish_timeout <<= 1;
1921                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1922                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1923                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
1924                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
1925         } else {
1926                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
1927                 queue_delayed_work(rpciod_workqueue,
1928                                    &transport->connect_worker, 0);
1929         }
1930 }
1931
1932 /**
1933  * xs_udp_print_stats - display UDP socket-specifc stats
1934  * @xprt: rpc_xprt struct containing statistics
1935  * @seq: output file
1936  *
1937  */
1938 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1939 {
1940         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1941
1942         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
1943                         transport->srcport,
1944                         xprt->stat.bind_count,
1945                         xprt->stat.sends,
1946                         xprt->stat.recvs,
1947                         xprt->stat.bad_xids,
1948                         xprt->stat.req_u,
1949                         xprt->stat.bklog_u);
1950 }
1951
1952 /**
1953  * xs_tcp_print_stats - display TCP socket-specifc stats
1954  * @xprt: rpc_xprt struct containing statistics
1955  * @seq: output file
1956  *
1957  */
1958 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
1959 {
1960         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1961         long idle_time = 0;
1962
1963         if (xprt_connected(xprt))
1964                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
1965
1966         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
1967                         transport->srcport,
1968                         xprt->stat.bind_count,
1969                         xprt->stat.connect_count,
1970                         xprt->stat.connect_time,
1971                         idle_time,
1972                         xprt->stat.sends,
1973                         xprt->stat.recvs,
1974                         xprt->stat.bad_xids,
1975                         xprt->stat.req_u,
1976                         xprt->stat.bklog_u);
1977 }
1978
1979 /*
1980  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
1981  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
1982  * to use the server side send routines.
1983  */
1984 static void *bc_malloc(struct rpc_task *task, size_t size)
1985 {
1986         struct page *page;
1987         struct rpc_buffer *buf;
1988
1989         BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
1990         page = alloc_page(GFP_KERNEL);
1991
1992         if (!page)
1993                 return NULL;
1994
1995         buf = page_address(page);
1996         buf->len = PAGE_SIZE;
1997
1998         return buf->data;
1999 }
2000
2001 /*
2002  * Free the space allocated in the bc_alloc routine
2003  */
2004 static void bc_free(void *buffer)
2005 {
2006         struct rpc_buffer *buf;
2007
2008         if (!buffer)
2009                 return;
2010
2011         buf = container_of(buffer, struct rpc_buffer, data);
2012         free_page((unsigned long)buf);
2013 }
2014
2015 /*
2016  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2017  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2018  */
2019 static int bc_sendto(struct rpc_rqst *req)
2020 {
2021         int len;
2022         struct xdr_buf *xbufp = &req->rq_snd_buf;
2023         struct rpc_xprt *xprt = req->rq_xprt;
2024         struct sock_xprt *transport =
2025                                 container_of(xprt, struct sock_xprt, xprt);
2026         struct socket *sock = transport->sock;
2027         unsigned long headoff;
2028         unsigned long tailoff;
2029
2030         xs_encode_stream_record_marker(xbufp);
2031
2032         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2033         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2034         len = svc_send_common(sock, xbufp,
2035                               virt_to_page(xbufp->head[0].iov_base), headoff,
2036                               xbufp->tail[0].iov_base, tailoff);
2037
2038         if (len != xbufp->len) {
2039                 printk(KERN_NOTICE "Error sending entire callback!\n");
2040                 len = -EAGAIN;
2041         }
2042
2043         return len;
2044 }
2045
2046 /*
2047  * The send routine. Borrows from svc_send
2048  */
2049 static int bc_send_request(struct rpc_task *task)
2050 {
2051         struct rpc_rqst *req = task->tk_rqstp;
2052         struct svc_xprt *xprt;
2053         struct svc_sock         *svsk;
2054         u32                     len;
2055
2056         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2057         /*
2058          * Get the server socket associated with this callback xprt
2059          */
2060         xprt = req->rq_xprt->bc_xprt;
2061         svsk = container_of(xprt, struct svc_sock, sk_xprt);
2062
2063         /*
2064          * Grab the mutex to serialize data as the connection is shared
2065          * with the fore channel
2066          */
2067         if (!mutex_trylock(&xprt->xpt_mutex)) {
2068                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2069                 if (!mutex_trylock(&xprt->xpt_mutex))
2070                         return -EAGAIN;
2071                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2072         }
2073         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2074                 len = -ENOTCONN;
2075         else
2076                 len = bc_sendto(req);
2077         mutex_unlock(&xprt->xpt_mutex);
2078
2079         if (len > 0)
2080                 len = 0;
2081
2082         return len;
2083 }
2084
2085 /*
2086  * The close routine. Since this is client initiated, we do nothing
2087  */
2088
2089 static void bc_close(struct rpc_xprt *xprt)
2090 {
2091 }
2092
2093 /*
2094  * The xprt destroy routine. Again, because this connection is client
2095  * initiated, we do nothing
2096  */
2097
2098 static void bc_destroy(struct rpc_xprt *xprt)
2099 {
2100 }
2101
2102 static struct rpc_xprt_ops xs_udp_ops = {
2103         .set_buffer_size        = xs_udp_set_buffer_size,
2104         .reserve_xprt           = xprt_reserve_xprt_cong,
2105         .release_xprt           = xprt_release_xprt_cong,
2106         .rpcbind                = rpcb_getport_async,
2107         .set_port               = xs_set_port,
2108         .connect                = xs_connect,
2109         .buf_alloc              = rpc_malloc,
2110         .buf_free               = rpc_free,
2111         .send_request           = xs_udp_send_request,
2112         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2113         .timer                  = xs_udp_timer,
2114         .release_request        = xprt_release_rqst_cong,
2115         .close                  = xs_close,
2116         .destroy                = xs_destroy,
2117         .print_stats            = xs_udp_print_stats,
2118 };
2119
2120 static struct rpc_xprt_ops xs_tcp_ops = {
2121         .reserve_xprt           = xprt_reserve_xprt,
2122         .release_xprt           = xs_tcp_release_xprt,
2123         .rpcbind                = rpcb_getport_async,
2124         .set_port               = xs_set_port,
2125         .connect                = xs_connect,
2126         .buf_alloc              = rpc_malloc,
2127         .buf_free               = rpc_free,
2128         .send_request           = xs_tcp_send_request,
2129         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2130         .close                  = xs_tcp_close,
2131         .destroy                = xs_destroy,
2132         .print_stats            = xs_tcp_print_stats,
2133 };
2134
2135 /*
2136  * The rpc_xprt_ops for the server backchannel
2137  */
2138
2139 static struct rpc_xprt_ops bc_tcp_ops = {
2140         .reserve_xprt           = xprt_reserve_xprt,
2141         .release_xprt           = xprt_release_xprt,
2142         .buf_alloc              = bc_malloc,
2143         .buf_free               = bc_free,
2144         .send_request           = bc_send_request,
2145         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2146         .close                  = bc_close,
2147         .destroy                = bc_destroy,
2148         .print_stats            = xs_tcp_print_stats,
2149 };
2150
2151 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2152 {
2153         static const struct sockaddr_in sin = {
2154                 .sin_family             = AF_INET,
2155                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2156         };
2157         static const struct sockaddr_in6 sin6 = {
2158                 .sin6_family            = AF_INET6,
2159                 .sin6_addr              = IN6ADDR_ANY_INIT,
2160         };
2161
2162         switch (family) {
2163         case AF_INET:
2164                 memcpy(sap, &sin, sizeof(sin));
2165                 break;
2166         case AF_INET6:
2167                 memcpy(sap, &sin6, sizeof(sin6));
2168                 break;
2169         default:
2170                 dprintk("RPC:       %s: Bad address family\n", __func__);
2171                 return -EAFNOSUPPORT;
2172         }
2173         return 0;
2174 }
2175
2176 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2177                                       unsigned int slot_table_size)
2178 {
2179         struct rpc_xprt *xprt;
2180         struct sock_xprt *new;
2181
2182         if (args->addrlen > sizeof(xprt->addr)) {
2183                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2184                 return ERR_PTR(-EBADF);
2185         }
2186
2187         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size);
2188         if (xprt == NULL) {
2189                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2190                                 "rpc_xprt\n");
2191                 return ERR_PTR(-ENOMEM);
2192         }
2193
2194         new = container_of(xprt, struct sock_xprt, xprt);
2195         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2196         xprt->addrlen = args->addrlen;
2197         if (args->srcaddr)
2198                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2199         else {
2200                 int err;
2201                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2202                                         (struct sockaddr *)&new->srcaddr);
2203                 if (err != 0)
2204                         return ERR_PTR(err);
2205         }
2206
2207         return xprt;
2208 }
2209
2210 static const struct rpc_timeout xs_udp_default_timeout = {
2211         .to_initval = 5 * HZ,
2212         .to_maxval = 30 * HZ,
2213         .to_increment = 5 * HZ,
2214         .to_retries = 5,
2215 };
2216
2217 /**
2218  * xs_setup_udp - Set up transport to use a UDP socket
2219  * @args: rpc transport creation arguments
2220  *
2221  */
2222 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2223 {
2224         struct sockaddr *addr = args->dstaddr;
2225         struct rpc_xprt *xprt;
2226         struct sock_xprt *transport;
2227         struct rpc_xprt *ret;
2228
2229         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
2230         if (IS_ERR(xprt))
2231                 return xprt;
2232         transport = container_of(xprt, struct sock_xprt, xprt);
2233
2234         xprt->prot = IPPROTO_UDP;
2235         xprt->tsh_size = 0;
2236         /* XXX: header size can vary due to auth type, IPv6, etc. */
2237         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2238
2239         xprt->bind_timeout = XS_BIND_TO;
2240         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2241         xprt->idle_timeout = XS_IDLE_DISC_TO;
2242
2243         xprt->ops = &xs_udp_ops;
2244
2245         xprt->timeout = &xs_udp_default_timeout;
2246
2247         switch (addr->sa_family) {
2248         case AF_INET:
2249                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2250                         xprt_set_bound(xprt);
2251
2252                 INIT_DELAYED_WORK(&transport->connect_worker,
2253                                         xs_udp_setup_socket);
2254                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2255                 break;
2256         case AF_INET6:
2257                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2258                         xprt_set_bound(xprt);
2259
2260                 INIT_DELAYED_WORK(&transport->connect_worker,
2261                                         xs_udp_setup_socket);
2262                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2263                 break;
2264         default:
2265                 ret = ERR_PTR(-EAFNOSUPPORT);
2266                 goto out_err;
2267         }
2268
2269         if (xprt_bound(xprt))
2270                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2271                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2272                                 xprt->address_strings[RPC_DISPLAY_PORT],
2273                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2274         else
2275                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2276                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2277                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2278
2279         if (try_module_get(THIS_MODULE))
2280                 return xprt;
2281         ret = ERR_PTR(-EINVAL);
2282 out_err:
2283         xprt_free(xprt);
2284         return ret;
2285 }
2286
2287 static const struct rpc_timeout xs_tcp_default_timeout = {
2288         .to_initval = 60 * HZ,
2289         .to_maxval = 60 * HZ,
2290         .to_retries = 2,
2291 };
2292
2293 /**
2294  * xs_setup_tcp - Set up transport to use a TCP socket
2295  * @args: rpc transport creation arguments
2296  *
2297  */
2298 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2299 {
2300         struct sockaddr *addr = args->dstaddr;
2301         struct rpc_xprt *xprt;
2302         struct sock_xprt *transport;
2303         struct rpc_xprt *ret;
2304
2305         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2306         if (IS_ERR(xprt))
2307                 return xprt;
2308         transport = container_of(xprt, struct sock_xprt, xprt);
2309
2310         xprt->prot = IPPROTO_TCP;
2311         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2312         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2313
2314         xprt->bind_timeout = XS_BIND_TO;
2315         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2316         xprt->idle_timeout = XS_IDLE_DISC_TO;
2317
2318         xprt->ops = &xs_tcp_ops;
2319         xprt->timeout = &xs_tcp_default_timeout;
2320
2321         switch (addr->sa_family) {
2322         case AF_INET:
2323                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2324                         xprt_set_bound(xprt);
2325
2326                 INIT_DELAYED_WORK(&transport->connect_worker,
2327                                         xs_tcp_setup_socket);
2328                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2329                 break;
2330         case AF_INET6:
2331                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2332                         xprt_set_bound(xprt);
2333
2334                 INIT_DELAYED_WORK(&transport->connect_worker,
2335                                         xs_tcp_setup_socket);
2336                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2337                 break;
2338         default:
2339                 ret = ERR_PTR(-EAFNOSUPPORT);
2340                 goto out_err;
2341         }
2342
2343         if (xprt_bound(xprt))
2344                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2345                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2346                                 xprt->address_strings[RPC_DISPLAY_PORT],
2347                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2348         else
2349                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2350                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2351                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2352
2353
2354         if (try_module_get(THIS_MODULE))
2355                 return xprt;
2356         ret = ERR_PTR(-EINVAL);
2357 out_err:
2358         xprt_free(xprt);
2359         return ret;
2360 }
2361
2362 /**
2363  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2364  * @args: rpc transport creation arguments
2365  *
2366  */
2367 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2368 {
2369         struct sockaddr *addr = args->dstaddr;
2370         struct rpc_xprt *xprt;
2371         struct sock_xprt *transport;
2372         struct svc_sock *bc_sock;
2373         struct rpc_xprt *ret;
2374
2375         if (args->bc_xprt->xpt_bc_xprt) {
2376                 /*
2377                  * This server connection already has a backchannel
2378                  * export; we can't create a new one, as we wouldn't be
2379                  * able to match replies based on xid any more.  So,
2380                  * reuse the already-existing one:
2381                  */
2382                  return args->bc_xprt->xpt_bc_xprt;
2383         }
2384         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2385         if (IS_ERR(xprt))
2386                 return xprt;
2387         transport = container_of(xprt, struct sock_xprt, xprt);
2388
2389         xprt->prot = IPPROTO_TCP;
2390         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2391         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2392         xprt->timeout = &xs_tcp_default_timeout;
2393
2394         /* backchannel */
2395         xprt_set_bound(xprt);
2396         xprt->bind_timeout = 0;
2397         xprt->reestablish_timeout = 0;
2398         xprt->idle_timeout = 0;
2399
2400         xprt->ops = &bc_tcp_ops;
2401
2402         switch (addr->sa_family) {
2403         case AF_INET:
2404                 xs_format_peer_addresses(xprt, "tcp",
2405                                          RPCBIND_NETID_TCP);
2406                 break;
2407         case AF_INET6:
2408                 xs_format_peer_addresses(xprt, "tcp",
2409                                    RPCBIND_NETID_TCP6);
2410                 break;
2411         default:
2412                 ret = ERR_PTR(-EAFNOSUPPORT);
2413                 goto out_err;
2414         }
2415
2416         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2417                         xprt->address_strings[RPC_DISPLAY_ADDR],
2418                         xprt->address_strings[RPC_DISPLAY_PORT],
2419                         xprt->address_strings[RPC_DISPLAY_PROTO]);
2420
2421         /*
2422          * Once we've associated a backchannel xprt with a connection,
2423          * we want to keep it around as long as long as the connection
2424          * lasts, in case we need to start using it for a backchannel
2425          * again; this reference won't be dropped until bc_xprt is
2426          * destroyed.
2427          */
2428         xprt_get(xprt);
2429         args->bc_xprt->xpt_bc_xprt = xprt;
2430         xprt->bc_xprt = args->bc_xprt;
2431         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2432         transport->sock = bc_sock->sk_sock;
2433         transport->inet = bc_sock->sk_sk;
2434
2435         /*
2436          * Since we don't want connections for the backchannel, we set
2437          * the xprt status to connected
2438          */
2439         xprt_set_connected(xprt);
2440
2441
2442         if (try_module_get(THIS_MODULE))
2443                 return xprt;
2444         xprt_put(xprt);
2445         ret = ERR_PTR(-EINVAL);
2446 out_err:
2447         xprt_free(xprt);
2448         return ret;
2449 }
2450
2451 static struct xprt_class        xs_udp_transport = {
2452         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2453         .name           = "udp",
2454         .owner          = THIS_MODULE,
2455         .ident          = XPRT_TRANSPORT_UDP,
2456         .setup          = xs_setup_udp,
2457 };
2458
2459 static struct xprt_class        xs_tcp_transport = {
2460         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
2461         .name           = "tcp",
2462         .owner          = THIS_MODULE,
2463         .ident          = XPRT_TRANSPORT_TCP,
2464         .setup          = xs_setup_tcp,
2465 };
2466
2467 static struct xprt_class        xs_bc_tcp_transport = {
2468         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2469         .name           = "tcp NFSv4.1 backchannel",
2470         .owner          = THIS_MODULE,
2471         .ident          = XPRT_TRANSPORT_BC_TCP,
2472         .setup          = xs_setup_bc_tcp,
2473 };
2474
2475 /**
2476  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
2477  *
2478  */
2479 int init_socket_xprt(void)
2480 {
2481 #ifdef RPC_DEBUG
2482         if (!sunrpc_table_header)
2483                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
2484 #endif
2485
2486         xprt_register_transport(&xs_udp_transport);
2487         xprt_register_transport(&xs_tcp_transport);
2488         xprt_register_transport(&xs_bc_tcp_transport);
2489
2490         return 0;
2491 }
2492
2493 /**
2494  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
2495  *
2496  */
2497 void cleanup_socket_xprt(void)
2498 {
2499 #ifdef RPC_DEBUG
2500         if (sunrpc_table_header) {
2501                 unregister_sysctl_table(sunrpc_table_header);
2502                 sunrpc_table_header = NULL;
2503         }
2504 #endif
2505
2506         xprt_unregister_transport(&xs_udp_transport);
2507         xprt_unregister_transport(&xs_tcp_transport);
2508         xprt_unregister_transport(&xs_bc_tcp_transport);
2509 }
2510
2511 static int param_set_uint_minmax(const char *val,
2512                 const struct kernel_param *kp,
2513                 unsigned int min, unsigned int max)
2514 {
2515         unsigned long num;
2516         int ret;
2517
2518         if (!val)
2519                 return -EINVAL;
2520         ret = strict_strtoul(val, 0, &num);
2521         if (ret == -EINVAL || num < min || num > max)
2522                 return -EINVAL;
2523         *((unsigned int *)kp->arg) = num;
2524         return 0;
2525 }
2526
2527 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2528 {
2529         return param_set_uint_minmax(val, kp,
2530                         RPC_MIN_RESVPORT,
2531                         RPC_MAX_RESVPORT);
2532 }
2533
2534 static struct kernel_param_ops param_ops_portnr = {
2535         .set = param_set_portnr,
2536         .get = param_get_uint,
2537 };
2538
2539 #define param_check_portnr(name, p) \
2540         __param_check(name, p, unsigned int);
2541
2542 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
2543 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
2544
2545 static int param_set_slot_table_size(const char *val,
2546                                      const struct kernel_param *kp)
2547 {
2548         return param_set_uint_minmax(val, kp,
2549                         RPC_MIN_SLOT_TABLE,
2550                         RPC_MAX_SLOT_TABLE);
2551 }
2552
2553 static struct kernel_param_ops param_ops_slot_table_size = {
2554         .set = param_set_slot_table_size,
2555         .get = param_get_uint,
2556 };
2557
2558 #define param_check_slot_table_size(name, p) \
2559         __param_check(name, p, unsigned int);
2560
2561 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
2562                    slot_table_size, 0644);
2563 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
2564                    slot_table_size, 0644);
2565