net/sunrpc/xprtsock.c

   1 /*
   2  * linux/net/sunrpc/xprtsock.c
   3  *
   4  * Client-side transport implementation for sockets.
   5  *
   6  * TCP callback races fixes (C) 1998 Red Hat
   7  * TCP send fixes (C) 1998 Red Hat
   8  * TCP NFS related read + write fixes
   9  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  10  *
  11  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  12  * Fix behaviour when socket buffer is full.
  13  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  14  *
  15  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  16  *
  17  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  18  *   <gilles.quillard@bull.net>
  19  */
  20
  21 #include <linux/types.h>
  22 #include <linux/slab.h>
  23 #include <linux/module.h>
  24 #include <linux/capability.h>
  25 #include <linux/pagemap.h>
  26 #include <linux/errno.h>
  27 #include <linux/socket.h>
  28 #include <linux/in.h>
  29 #include <linux/net.h>
  30 #include <linux/mm.h>
  31 #include <linux/udp.h>
  32 #include <linux/tcp.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/sched.h>
  35 #include <linux/sunrpc/svcsock.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/file.h>
  38 #ifdef CONFIG_NFS_V4_1
  39 #include <linux/sunrpc/bc_xprt.h>
  40 #endif
  41
  42 #include <net/sock.h>
  43 #include <net/checksum.h>
  44 #include <net/udp.h>
  45 #include <net/tcp.h>
  46
  47 #include "sunrpc.h"
  48 /*
  49  * xprtsock tunables
  50  */
  51 unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  52 unsigned int xprt_tcp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  53
  54 unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  55 unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  56
  57 #define XS_TCP_LINGER_TO        (15U * HZ)
  58 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  59
  60 /*
  61  * We can register our own files under /proc/sys/sunrpc by
  62  * calling register_sysctl_table() again.  The files in that
  63  * directory become the union of all files registered there.
  64  *
  65  * We simply need to make sure that we don't collide with
  66  * someone else's file names!
  67  */
  68
  69 #ifdef RPC_DEBUG
  70
  71 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  72 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  73 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  74 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  75
  76 static struct ctl_table_header *sunrpc_table_header;
  77
  78 /*
  79  * FIXME: changing the UDP slot table size should also resize the UDP
  80  *        socket buffers for existing UDP transports
  81  */
  82 static ctl_table xs_tunables_table[] = {
  83         {
  84                 .procname       = "udp_slot_table_entries",
  85                 .data           = &xprt_udp_slot_table_entries,
  86                 .maxlen         = sizeof(unsigned int),
  87                 .mode           = 0644,
  88                 .proc_handler   = proc_dointvec_minmax,
  89                 .extra1         = &min_slot_table_size,
  90                 .extra2         = &max_slot_table_size
  91         },
  92         {
  93                 .procname       = "tcp_slot_table_entries",
  94                 .data           = &xprt_tcp_slot_table_entries,
  95                 .maxlen         = sizeof(unsigned int),
  96                 .mode           = 0644,
  97                 .proc_handler   = proc_dointvec_minmax,
  98                 .extra1         = &min_slot_table_size,
  99                 .extra2         = &max_slot_table_size
 100         },
 101         {
 102                 .procname       = "min_resvport",
 103                 .data           = &xprt_min_resvport,
 104                 .maxlen         = sizeof(unsigned int),
 105                 .mode           = 0644,
 106                 .proc_handler   = proc_dointvec_minmax,
 107                 .extra1         = &xprt_min_resvport_limit,
 108                 .extra2         = &xprt_max_resvport_limit
 109         },
 110         {
 111                 .procname       = "max_resvport",
 112                 .data           = &xprt_max_resvport,
 113                 .maxlen         = sizeof(unsigned int),
 114                 .mode           = 0644,
 115                 .proc_handler   = proc_dointvec_minmax,
 116                 .extra1         = &xprt_min_resvport_limit,
 117                 .extra2         = &xprt_max_resvport_limit
 118         },
 119         {
 120                 .procname       = "tcp_fin_timeout",
 121                 .data           = &xs_tcp_fin_timeout,
 122                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 123                 .mode           = 0644,
 124                 .proc_handler   = proc_dointvec_jiffies,
 125         },
 126         { },
 127 };
 128
 129 static ctl_table sunrpc_table[] = {
 130         {
 131                 .procname       = "sunrpc",
 132                 .mode           = 0555,
 133                 .child          = xs_tunables_table
 134         },
 135         { },
 136 };
 137
 138 #endif
 139
 140 /*
 141  * Wait duration for a reply from the RPC portmapper.
 142  */
 143 #define XS_BIND_TO              (60U * HZ)
 144
 145 /*
 146  * Delay if a UDP socket connect error occurs.  This is most likely some
 147  * kind of resource problem on the local host.
 148  */
 149 #define XS_UDP_REEST_TO         (2U * HZ)
 150
 151 /*
 152  * The reestablish timeout allows clients to delay for a bit before attempting
 153  * to reconnect to a server that just dropped our connection.
 154  *
 155  * We implement an exponential backoff when trying to reestablish a TCP
 156  * transport connection with the server.  Some servers like to drop a TCP
 157  * connection when they are overworked, so we start with a short timeout and
 158  * increase over time if the server is down or not responding.
 159  */
 160 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 161 #define XS_TCP_MAX_REEST_TO     (5U * 60 * HZ)
 162
 163 /*
 164  * TCP idle timeout; client drops the transport socket if it is idle
 165  * for this long.  Note that we also timeout UDP sockets to prevent
 166  * holding port numbers when there is no RPC traffic.
 167  */
 168 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 169
 170 #ifdef RPC_DEBUG
 171 # undef  RPC_DEBUG_DATA
 172 # define RPCDBG_FACILITY        RPCDBG_TRANS
 173 #endif
 174
 175 #ifdef RPC_DEBUG_DATA
 176 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 177 {
 178         u8 *buf = (u8 *) packet;
 179         int j;
 180
 181         dprintk("RPC:       %s\n", msg);
 182         for (j = 0; j < count && j < 128; j += 4) {
 183                 if (!(j & 31)) {
 184                         if (j)
 185                                 dprintk("\n");
 186                         dprintk("0x%04x ", j);
 187                 }
 188                 dprintk("%02x%02x%02x%02x ",
 189                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 190         }
 191         dprintk("\n");
 192 }
 193 #else
 194 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 195 {
 196         /* NOP */
 197 }
 198 #endif
 199
 200 struct sock_xprt {
 201         struct rpc_xprt         xprt;
 202
 203         /*
 204          * Network layer
 205          */
 206         struct socket *         sock;
 207         struct sock *           inet;
 208
 209         /*
 210          * State of TCP reply receive
 211          */
 212         __be32                  tcp_fraghdr,
 213                                 tcp_xid,
 214                                 tcp_calldir;
 215
 216         u32                     tcp_offset,
 217                                 tcp_reclen;
 218
 219         unsigned long           tcp_copied,
 220                                 tcp_flags;
 221
 222         /*
 223          * Connection of transports
 224          */
 225         struct delayed_work     connect_worker;
 226         struct sockaddr_storage srcaddr;
 227         unsigned short          srcport;
 228
 229         /*
 230          * UDP socket buffer size parameters
 231          */
 232         size_t                  rcvsize,
 233                                 sndsize;
 234
 235         /*
 236          * Saved socket callback addresses
 237          */
 238         void                    (*old_data_ready)(struct sock *, int);
 239         void                    (*old_state_change)(struct sock *);
 240         void                    (*old_write_space)(struct sock *);
 241         void                    (*old_error_report)(struct sock *);
 242 };
 243
 244 /*
 245  * TCP receive state flags
 246  */
 247 #define TCP_RCV_LAST_FRAG       (1UL << 0)
 248 #define TCP_RCV_COPY_FRAGHDR    (1UL << 1)
 249 #define TCP_RCV_COPY_XID        (1UL << 2)
 250 #define TCP_RCV_COPY_DATA       (1UL << 3)
 251 #define TCP_RCV_READ_CALLDIR    (1UL << 4)
 252 #define TCP_RCV_COPY_CALLDIR    (1UL << 5)
 253
 254 /*
 255  * TCP RPC flags
 256  */
 257 #define TCP_RPC_REPLY           (1UL << 6)
 258
 259 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 260 {
 261         return (struct sockaddr *) &xprt->addr;
 262 }
 263
 264 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 265 {
 266         return (struct sockaddr_in *) &xprt->addr;
 267 }
 268
 269 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 270 {
 271         return (struct sockaddr_in6 *) &xprt->addr;
 272 }
 273
 274 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 275 {
 276         struct sockaddr *sap = xs_addr(xprt);
 277         struct sockaddr_in6 *sin6;
 278         struct sockaddr_in *sin;
 279         char buf[128];
 280
 281         (void)rpc_ntop(sap, buf, sizeof(buf));
 282         xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL);
 283
 284         switch (sap->sa_family) {
 285         case AF_INET:
 286                 sin = xs_addr_in(xprt);
 287                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 288                 break;
 289         case AF_INET6:
 290                 sin6 = xs_addr_in6(xprt);
 291                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 292                 break;
 293         default:
 294                 BUG();
 295         }
 296         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 297 }
 298
 299 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 300 {
 301         struct sockaddr *sap = xs_addr(xprt);
 302         char buf[128];
 303
 304         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 305         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 306
 307         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 308         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 309 }
 310
 311 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 312                                      const char *protocol,
 313                                      const char *netid)
 314 {
 315         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 316         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 317         xs_format_common_peer_addresses(xprt);
 318         xs_format_common_peer_ports(xprt);
 319 }
 320
 321 static void xs_update_peer_port(struct rpc_xprt *xprt)
 322 {
 323         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 324         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 325
 326         xs_format_common_peer_ports(xprt);
 327 }
 328
 329 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 330 {
 331         unsigned int i;
 332
 333         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 334                 switch (i) {
 335                 case RPC_DISPLAY_PROTO:
 336                 case RPC_DISPLAY_NETID:
 337                         continue;
 338                 default:
 339                         kfree(xprt->address_strings[i]);
 340                 }
 341 }
 342
 343 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 344
 345 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 346 {
 347         struct msghdr msg = {
 348                 .msg_name       = addr,
 349                 .msg_namelen    = addrlen,
 350                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 351         };
 352         struct kvec iov = {
 353                 .iov_base       = vec->iov_base + base,
 354                 .iov_len        = vec->iov_len - base,
 355         };
 356
 357         if (iov.iov_len != 0)
 358                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 359         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 360 }
 361
 362 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more)
 363 {
 364         struct page **ppage;
 365         unsigned int remainder;
 366         int err, sent = 0;
 367
 368         remainder = xdr->page_len - base;
 369         base += xdr->page_base;
 370         ppage = xdr->pages + (base >> PAGE_SHIFT);
 371         base &= ~PAGE_MASK;
 372         for(;;) {
 373                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 374                 int flags = XS_SENDMSG_FLAGS;
 375
 376                 remainder -= len;
 377                 if (remainder != 0 || more)
 378                         flags |= MSG_MORE;
 379                 err = sock->ops->sendpage(sock, *ppage, base, len, flags);
 380                 if (remainder == 0 || err != len)
 381                         break;
 382                 sent += err;
 383                 ppage++;
 384                 base = 0;
 385         }
 386         if (sent == 0)
 387                 return err;
 388         if (err > 0)
 389                 sent += err;
 390         return sent;
 391 }
 392
 393 /**
 394  * xs_sendpages - write pages directly to a socket
 395  * @sock: socket to send on
 396  * @addr: UDP only -- address of destination
 397  * @addrlen: UDP only -- length of destination address
 398  * @xdr: buffer containing this request
 399  * @base: starting position in the buffer
 400  *
 401  */
 402 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base)
 403 {
 404         unsigned int remainder = xdr->len - base;
 405         int err, sent = 0;
 406
 407         if (unlikely(!sock))
 408                 return -ENOTSOCK;
 409
 410         clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 411         if (base != 0) {
 412                 addr = NULL;
 413                 addrlen = 0;
 414         }
 415
 416         if (base < xdr->head[0].iov_len || addr != NULL) {
 417                 unsigned int len = xdr->head[0].iov_len - base;
 418                 remainder -= len;
 419                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 420                 if (remainder == 0 || err != len)
 421                         goto out;
 422                 sent += err;
 423                 base = 0;
 424         } else
 425                 base -= xdr->head[0].iov_len;
 426
 427         if (base < xdr->page_len) {
 428                 unsigned int len = xdr->page_len - base;
 429                 remainder -= len;
 430                 err = xs_send_pagedata(sock, xdr, base, remainder != 0);
 431                 if (remainder == 0 || err != len)
 432                         goto out;
 433                 sent += err;
 434                 base = 0;
 435         } else
 436                 base -= xdr->page_len;
 437
 438         if (base >= xdr->tail[0].iov_len)
 439                 return sent;
 440         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 441 out:
 442         if (sent == 0)
 443                 return err;
 444         if (err > 0)
 445                 sent += err;
 446         return sent;
 447 }
 448
 449 static void xs_nospace_callback(struct rpc_task *task)
 450 {
 451         struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 452
 453         transport->inet->sk_write_pending--;
 454         clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 455 }
 456
 457 /**
 458  * xs_nospace - place task on wait queue if transmit was incomplete
 459  * @task: task to put to sleep
 460  *
 461  */
 462 static int xs_nospace(struct rpc_task *task)
 463 {
 464         struct rpc_rqst *req = task->tk_rqstp;
 465         struct rpc_xprt *xprt = req->rq_xprt;
 466         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 467         int ret = 0;
 468
 469         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 470                         task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 471                         req->rq_slen);
 472
 473         /* Protect against races with write_space */
 474         spin_lock_bh(&xprt->transport_lock);
 475
 476         /* Don't race with disconnect */
 477         if (xprt_connected(xprt)) {
 478                 if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
 479                         ret = -EAGAIN;
 480                         /*
 481                          * Notify TCP that we're limited by the application
 482                          * window size
 483                          */
 484                         set_bit(SOCK_NOSPACE, &transport->sock->flags);
 485                         transport->inet->sk_write_pending++;
 486                         /* ...and wait for more buffer space */
 487                         xprt_wait_for_buffer_space(task, xs_nospace_callback);
 488                 }
 489         } else {
 490                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 491                 ret = -ENOTCONN;
 492         }
 493
 494         spin_unlock_bh(&xprt->transport_lock);
 495         return ret;
 496 }
 497
 498 /**
 499  * xs_udp_send_request - write an RPC request to a UDP socket
 500  * @task: address of RPC task that manages the state of an RPC request
 501  *
 502  * Return values:
 503  *        0:    The request has been sent
 504  *   EAGAIN:    The socket was blocked, please call again later to
 505  *              complete the request
 506  * ENOTCONN:    Caller needs to invoke connect logic then call again
 507  *    other:    Some other error occured, the request was not sent
 508  */
 509 static int xs_udp_send_request(struct rpc_task *task)
 510 {
 511         struct rpc_rqst *req = task->tk_rqstp;
 512         struct rpc_xprt *xprt = req->rq_xprt;
 513         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 514         struct xdr_buf *xdr = &req->rq_snd_buf;
 515         int status;
 516
 517         xs_pktdump("packet data:",
 518                                 req->rq_svec->iov_base,
 519                                 req->rq_svec->iov_len);
 520
 521         if (!xprt_bound(xprt))
 522                 return -ENOTCONN;
 523         status = xs_sendpages(transport->sock,
 524                               xs_addr(xprt),
 525                               xprt->addrlen, xdr,
 526                               req->rq_bytes_sent);
 527
 528         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 529                         xdr->len - req->rq_bytes_sent, status);
 530
 531         if (status >= 0) {
 532                 req->rq_xmit_bytes_sent += status;
 533                 if (status >= req->rq_slen)
 534                         return 0;
 535                 /* Still some bytes left; set up for a retry later. */
 536                 status = -EAGAIN;
 537         }
 538
 539         switch (status) {
 540         case -ENOTSOCK:
 541                 status = -ENOTCONN;
 542                 /* Should we call xs_close() here? */
 543                 break;
 544         case -EAGAIN:
 545                 status = xs_nospace(task);
 546                 break;
 547         default:
 548                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 549                         -status);
 550         case -ENETUNREACH:
 551         case -EPIPE:
 552         case -ECONNREFUSED:
 553                 /* When the server has died, an ICMP port unreachable message
 554                  * prompts ECONNREFUSED. */
 555                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 556         }
 557
 558         return status;
 559 }
 560
 561 /**
 562  * xs_tcp_shutdown - gracefully shut down a TCP socket
 563  * @xprt: transport
 564  *
 565  * Initiates a graceful shutdown of the TCP socket by calling the
 566  * equivalent of shutdown(SHUT_WR);
 567  */
 568 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 569 {
 570         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 571         struct socket *sock = transport->sock;
 572
 573         if (sock != NULL)
 574                 kernel_sock_shutdown(sock, SHUT_WR);
 575 }
 576
 577 static inline void xs_encode_tcp_record_marker(struct xdr_buf *buf)
 578 {
 579         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 580         rpc_fraghdr *base = buf->head[0].iov_base;
 581         *base = htonl(RPC_LAST_STREAM_FRAGMENT | reclen);
 582 }
 583
 584 /**
 585  * xs_tcp_send_request - write an RPC request to a TCP socket
 586  * @task: address of RPC task that manages the state of an RPC request
 587  *
 588  * Return values:
 589  *        0:    The request has been sent
 590  *   EAGAIN:    The socket was blocked, please call again later to
 591  *              complete the request
 592  * ENOTCONN:    Caller needs to invoke connect logic then call again
 593  *    other:    Some other error occured, the request was not sent
 594  *
 595  * XXX: In the case of soft timeouts, should we eventually give up
 596  *      if sendmsg is not able to make progress?
 597  */
 598 static int xs_tcp_send_request(struct rpc_task *task)
 599 {
 600         struct rpc_rqst *req = task->tk_rqstp;
 601         struct rpc_xprt *xprt = req->rq_xprt;
 602         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 603         struct xdr_buf *xdr = &req->rq_snd_buf;
 604         int status;
 605
 606         xs_encode_tcp_record_marker(&req->rq_snd_buf);
 607
 608         xs_pktdump("packet data:",
 609                                 req->rq_svec->iov_base,
 610                                 req->rq_svec->iov_len);
 611
 612         /* Continue transmitting the packet/record. We must be careful
 613          * to cope with writespace callbacks arriving _after_ we have
 614          * called sendmsg(). */
 615         while (1) {
 616                 status = xs_sendpages(transport->sock,
 617                                         NULL, 0, xdr, req->rq_bytes_sent);
 618
 619                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 620                                 xdr->len - req->rq_bytes_sent, status);
 621
 622                 if (unlikely(status < 0))
 623                         break;
 624
 625                 /* If we've sent the entire packet, immediately
 626                  * reset the count of bytes sent. */
 627                 req->rq_bytes_sent += status;
 628                 req->rq_xmit_bytes_sent += status;
 629                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 630                         req->rq_bytes_sent = 0;
 631                         return 0;
 632                 }
 633
 634                 if (status != 0)
 635                         continue;
 636                 status = -EAGAIN;
 637                 break;
 638         }
 639
 640         switch (status) {
 641         case -ENOTSOCK:
 642                 status = -ENOTCONN;
 643                 /* Should we call xs_close() here? */
 644                 break;
 645         case -EAGAIN:
 646                 status = xs_nospace(task);
 647                 break;
 648         default:
 649                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 650                         -status);
 651         case -ECONNRESET:
 652         case -EPIPE:
 653                 xs_tcp_shutdown(xprt);
 654         case -ECONNREFUSED:
 655         case -ENOTCONN:
 656                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 657         }
 658
 659         return status;
 660 }
 661
 662 /**
 663  * xs_tcp_release_xprt - clean up after a tcp transmission
 664  * @xprt: transport
 665  * @task: rpc task
 666  *
 667  * This cleans up if an error causes us to abort the transmission of a request.
 668  * In this case, the socket may need to be reset in order to avoid confusing
 669  * the server.
 670  */
 671 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 672 {
 673         struct rpc_rqst *req;
 674
 675         if (task != xprt->snd_task)
 676                 return;
 677         if (task == NULL)
 678                 goto out_release;
 679         req = task->tk_rqstp;
 680         if (req->rq_bytes_sent == 0)
 681                 goto out_release;
 682         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 683                 goto out_release;
 684         set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
 685 out_release:
 686         xprt_release_xprt(xprt, task);
 687 }
 688
 689 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 690 {
 691         transport->old_data_ready = sk->sk_data_ready;
 692         transport->old_state_change = sk->sk_state_change;
 693         transport->old_write_space = sk->sk_write_space;
 694         transport->old_error_report = sk->sk_error_report;
 695 }
 696
 697 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 698 {
 699         sk->sk_data_ready = transport->old_data_ready;
 700         sk->sk_state_change = transport->old_state_change;
 701         sk->sk_write_space = transport->old_write_space;
 702         sk->sk_error_report = transport->old_error_report;
 703 }
 704
 705 static void xs_reset_transport(struct sock_xprt *transport)
 706 {
 707         struct socket *sock = transport->sock;
 708         struct sock *sk = transport->inet;
 709
 710         if (sk == NULL)
 711                 return;
 712
 713         write_lock_bh(&sk->sk_callback_lock);
 714         transport->inet = NULL;
 715         transport->sock = NULL;
 716
 717         sk->sk_user_data = NULL;
 718
 719         xs_restore_old_callbacks(transport, sk);
 720         write_unlock_bh(&sk->sk_callback_lock);
 721
 722         sk->sk_no_check = 0;
 723
 724         sock_release(sock);
 725 }
 726
 727 /**
 728  * xs_close - close a socket
 729  * @xprt: transport
 730  *
 731  * This is used when all requests are complete; ie, no DRC state remains
 732  * on the server we want to save.
 733  *
 734  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 735  * xs_reset_transport() zeroing the socket from underneath a writer.
 736  */
 737 static void xs_close(struct rpc_xprt *xprt)
 738 {
 739         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 740
 741         dprintk("RPC:       xs_close xprt %p\n", xprt);
 742
 743         xs_reset_transport(transport);
 744         xprt->reestablish_timeout = 0;
 745
 746         smp_mb__before_clear_bit();
 747         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 748         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 749         clear_bit(XPRT_CLOSING, &xprt->state);
 750         smp_mb__after_clear_bit();
 751         xprt_disconnect_done(xprt);
 752 }
 753
 754 static void xs_tcp_close(struct rpc_xprt *xprt)
 755 {
 756         if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 757                 xs_close(xprt);
 758         else
 759                 xs_tcp_shutdown(xprt);
 760 }
 761
 762 /**
 763  * xs_destroy - prepare to shutdown a transport
 764  * @xprt: doomed transport
 765  *
 766  */
 767 static void xs_destroy(struct rpc_xprt *xprt)
 768 {
 769         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 770
 771         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 772
 773         cancel_rearming_delayed_work(&transport->connect_worker);
 774
 775         xs_close(xprt);
 776         xs_free_peer_addresses(xprt);
 777         kfree(xprt->slot);
 778         kfree(xprt);
 779         module_put(THIS_MODULE);
 780 }
 781
 782 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 783 {
 784         return (struct rpc_xprt *) sk->sk_user_data;
 785 }
 786
 787 /**
 788  * xs_udp_data_ready - "data ready" callback for UDP sockets
 789  * @sk: socket with data to read
 790  * @len: how much data to read
 791  *
 792  */
 793 static void xs_udp_data_ready(struct sock *sk, int len)
 794 {
 795         struct rpc_task *task;
 796         struct rpc_xprt *xprt;
 797         struct rpc_rqst *rovr;
 798         struct sk_buff *skb;
 799         int err, repsize, copied;
 800         u32 _xid;
 801         __be32 *xp;
 802
 803         read_lock_bh(&sk->sk_callback_lock);
 804         dprintk("RPC:       xs_udp_data_ready...\n");
 805         if (!(xprt = xprt_from_sock(sk)))
 806                 goto out;
 807
 808         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 809                 goto out;
 810
 811         if (xprt->shutdown)
 812                 goto dropit;
 813
 814         repsize = skb->len - sizeof(struct udphdr);
 815         if (repsize < 4) {
 816                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
 817                 goto dropit;
 818         }
 819
 820         /* Copy the XID from the skb... */
 821         xp = skb_header_pointer(skb, sizeof(struct udphdr),
 822                                 sizeof(_xid), &_xid);
 823         if (xp == NULL)
 824                 goto dropit;
 825
 826         /* Look up and lock the request corresponding to the given XID */
 827         spin_lock(&xprt->transport_lock);
 828         rovr = xprt_lookup_rqst(xprt, *xp);
 829         if (!rovr)
 830                 goto out_unlock;
 831         task = rovr->rq_task;
 832
 833         if ((copied = rovr->rq_private_buf.buflen) > repsize)
 834                 copied = repsize;
 835
 836         /* Suck it into the iovec, verify checksum if not done by hw. */
 837         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 838                 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
 839                 goto out_unlock;
 840         }
 841
 842         UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
 843
 844         /* Something worked... */
 845         dst_confirm(skb_dst(skb));
 846
 847         xprt_adjust_cwnd(task, copied);
 848         xprt_complete_rqst(task, copied);
 849
 850  out_unlock:
 851         spin_unlock(&xprt->transport_lock);
 852  dropit:
 853         skb_free_datagram(sk, skb);
 854  out:
 855         read_unlock_bh(&sk->sk_callback_lock);
 856 }
 857
 858 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
 859 {
 860         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 861         size_t len, used;
 862         char *p;
 863
 864         p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
 865         len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
 866         used = xdr_skb_read_bits(desc, p, len);
 867         transport->tcp_offset += used;
 868         if (used != len)
 869                 return;
 870
 871         transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
 872         if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
 873                 transport->tcp_flags |= TCP_RCV_LAST_FRAG;
 874         else
 875                 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
 876         transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
 877
 878         transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
 879         transport->tcp_offset = 0;
 880
 881         /* Sanity check of the record length */
 882         if (unlikely(transport->tcp_reclen < 8)) {
 883                 dprintk("RPC:       invalid TCP record fragment length\n");
 884                 xprt_force_disconnect(xprt);
 885                 return;
 886         }
 887         dprintk("RPC:       reading TCP record fragment of length %d\n",
 888                         transport->tcp_reclen);
 889 }
 890
 891 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
 892 {
 893         if (transport->tcp_offset == transport->tcp_reclen) {
 894                 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
 895                 transport->tcp_offset = 0;
 896                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
 897                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
 898                         transport->tcp_flags |= TCP_RCV_COPY_XID;
 899                         transport->tcp_copied = 0;
 900                 }
 901         }
 902 }
 903
 904 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
 905 {
 906         size_t len, used;
 907         char *p;
 908
 909         len = sizeof(transport->tcp_xid) - transport->tcp_offset;
 910         dprintk("RPC:       reading XID (%Zu bytes)\n", len);
 911         p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
 912         used = xdr_skb_read_bits(desc, p, len);
 913         transport->tcp_offset += used;
 914         if (used != len)
 915                 return;
 916         transport->tcp_flags &= ~TCP_RCV_COPY_XID;
 917         transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
 918         transport->tcp_copied = 4;
 919         dprintk("RPC:       reading %s XID %08x\n",
 920                         (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
 921                                                               : "request with",
 922                         ntohl(transport->tcp_xid));
 923         xs_tcp_check_fraghdr(transport);
 924 }
 925
 926 static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
 927                                        struct xdr_skb_reader *desc)
 928 {
 929         size_t len, used;
 930         u32 offset;
 931         char *p;
 932
 933         /*
 934          * We want transport->tcp_offset to be 8 at the end of this routine
 935          * (4 bytes for the xid and 4 bytes for the call/reply flag).
 936          * When this function is called for the first time,
 937          * transport->tcp_offset is 4 (after having already read the xid).
 938          */
 939         offset = transport->tcp_offset - sizeof(transport->tcp_xid);
 940         len = sizeof(transport->tcp_calldir) - offset;
 941         dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
 942         p = ((char *) &transport->tcp_calldir) + offset;
 943         used = xdr_skb_read_bits(desc, p, len);
 944         transport->tcp_offset += used;
 945         if (used != len)
 946                 return;
 947         transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
 948         /*
 949          * We don't yet have the XDR buffer, so we will write the calldir
 950          * out after we get the buffer from the 'struct rpc_rqst'
 951          */
 952         switch (ntohl(transport->tcp_calldir)) {
 953         case RPC_REPLY:
 954                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
 955                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
 956                 transport->tcp_flags |= TCP_RPC_REPLY;
 957                 break;
 958         case RPC_CALL:
 959                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
 960                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
 961                 transport->tcp_flags &= ~TCP_RPC_REPLY;
 962                 break;
 963         default:
 964                 dprintk("RPC:       invalid request message type\n");
 965                 xprt_force_disconnect(&transport->xprt);
 966         }
 967         xs_tcp_check_fraghdr(transport);
 968 }
 969
 970 static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
 971                                      struct xdr_skb_reader *desc,
 972                                      struct rpc_rqst *req)
 973 {
 974         struct sock_xprt *transport =
 975                                 container_of(xprt, struct sock_xprt, xprt);
 976         struct xdr_buf *rcvbuf;
 977         size_t len;
 978         ssize_t r;
 979
 980         rcvbuf = &req->rq_private_buf;
 981
 982         if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
 983                 /*
 984                  * Save the RPC direction in the XDR buffer
 985                  */
 986                 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
 987                         &transport->tcp_calldir,
 988                         sizeof(transport->tcp_calldir));
 989                 transport->tcp_copied += sizeof(transport->tcp_calldir);
 990                 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
 991         }
 992
 993         len = desc->count;
 994         if (len > transport->tcp_reclen - transport->tcp_offset) {
 995                 struct xdr_skb_reader my_desc;
 996
 997                 len = transport->tcp_reclen - transport->tcp_offset;
 998                 memcpy(&my_desc, desc, sizeof(my_desc));
 999                 my_desc.count = len;
1000                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1001                                           &my_desc, xdr_skb_read_bits);
1002                 desc->count -= r;
1003                 desc->offset += r;
1004         } else
1005                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1006                                           desc, xdr_skb_read_bits);
1007
1008         if (r > 0) {
1009                 transport->tcp_copied += r;
1010                 transport->tcp_offset += r;
1011         }
1012         if (r != len) {
1013                 /* Error when copying to the receive buffer,
1014                  * usually because we weren't able to allocate
1015                  * additional buffer pages. All we can do now
1016                  * is turn off TCP_RCV_COPY_DATA, so the request
1017                  * will not receive any additional updates,
1018                  * and time out.
1019                  * Any remaining data from this record will
1020                  * be discarded.
1021                  */
1022                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1023                 dprintk("RPC:       XID %08x truncated request\n",
1024                                 ntohl(transport->tcp_xid));
1025                 dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1026                                 "tcp_offset = %u, tcp_reclen = %u\n",
1027                                 xprt, transport->tcp_copied,
1028                                 transport->tcp_offset, transport->tcp_reclen);
1029                 return;
1030         }
1031
1032         dprintk("RPC:       XID %08x read %Zd bytes\n",
1033                         ntohl(transport->tcp_xid), r);
1034         dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1035                         "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1036                         transport->tcp_offset, transport->tcp_reclen);
1037
1038         if (transport->tcp_copied == req->rq_private_buf.buflen)
1039                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1040         else if (transport->tcp_offset == transport->tcp_reclen) {
1041                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1042                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1043         }
1044 }
1045
1046 /*
1047  * Finds the request corresponding to the RPC xid and invokes the common
1048  * tcp read code to read the data.
1049  */
1050 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1051                                     struct xdr_skb_reader *desc)
1052 {
1053         struct sock_xprt *transport =
1054                                 container_of(xprt, struct sock_xprt, xprt);
1055         struct rpc_rqst *req;
1056
1057         dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1058
1059         /* Find and lock the request corresponding to this xid */
1060         spin_lock(&xprt->transport_lock);
1061         req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1062         if (!req) {
1063                 dprintk("RPC:       XID %08x request not found!\n",
1064                                 ntohl(transport->tcp_xid));
1065                 spin_unlock(&xprt->transport_lock);
1066                 return -1;
1067         }
1068
1069         xs_tcp_read_common(xprt, desc, req);
1070
1071         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1072                 xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1073
1074         spin_unlock(&xprt->transport_lock);
1075         return 0;
1076 }
1077
1078 #if defined(CONFIG_NFS_V4_1)
1079 /*
1080  * Obtains an rpc_rqst previously allocated and invokes the common
1081  * tcp read code to read the data.  The result is placed in the callback
1082  * queue.
1083  * If we're unable to obtain the rpc_rqst we schedule the closing of the
1084  * connection and return -1.
1085  */
1086 static inline int xs_tcp_read_callback(struct rpc_xprt *xprt,
1087                                        struct xdr_skb_reader *desc)
1088 {
1089         struct sock_xprt *transport =
1090                                 container_of(xprt, struct sock_xprt, xprt);
1091         struct rpc_rqst *req;
1092
1093         req = xprt_alloc_bc_request(xprt);
1094         if (req == NULL) {
1095                 printk(KERN_WARNING "Callback slot table overflowed\n");
1096                 xprt_force_disconnect(xprt);
1097                 return -1;
1098         }
1099
1100         req->rq_xid = transport->tcp_xid;
1101         dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1102         xs_tcp_read_common(xprt, desc, req);
1103
1104         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA)) {
1105                 struct svc_serv *bc_serv = xprt->bc_serv;
1106
1107                 /*
1108                  * Add callback request to callback list.  The callback
1109                  * service sleeps on the sv_cb_waitq waiting for new
1110                  * requests.  Wake it up after adding enqueing the
1111                  * request.
1112                  */
1113                 dprintk("RPC:       add callback request to list\n");
1114                 spin_lock(&bc_serv->sv_cb_lock);
1115                 list_add(&req->rq_bc_list, &bc_serv->sv_cb_list);
1116                 spin_unlock(&bc_serv->sv_cb_lock);
1117                 wake_up(&bc_serv->sv_cb_waitq);
1118         }
1119
1120         req->rq_private_buf.len = transport->tcp_copied;
1121
1122         return 0;
1123 }
1124
1125 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1126                                         struct xdr_skb_reader *desc)
1127 {
1128         struct sock_xprt *transport =
1129                                 container_of(xprt, struct sock_xprt, xprt);
1130
1131         return (transport->tcp_flags & TCP_RPC_REPLY) ?
1132                 xs_tcp_read_reply(xprt, desc) :
1133                 xs_tcp_read_callback(xprt, desc);
1134 }
1135 #else
1136 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1137                                         struct xdr_skb_reader *desc)
1138 {
1139         return xs_tcp_read_reply(xprt, desc);
1140 }
1141 #endif /* CONFIG_NFS_V4_1 */
1142
1143 /*
1144  * Read data off the transport.  This can be either an RPC_CALL or an
1145  * RPC_REPLY.  Relay the processing to helper functions.
1146  */
1147 static void xs_tcp_read_data(struct rpc_xprt *xprt,
1148                                     struct xdr_skb_reader *desc)
1149 {
1150         struct sock_xprt *transport =
1151                                 container_of(xprt, struct sock_xprt, xprt);
1152
1153         if (_xs_tcp_read_data(xprt, desc) == 0)
1154                 xs_tcp_check_fraghdr(transport);
1155         else {
1156                 /*
1157                  * The transport_lock protects the request handling.
1158                  * There's no need to hold it to update the tcp_flags.
1159                  */
1160                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1161         }
1162 }
1163
1164 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1165 {
1166         size_t len;
1167
1168         len = transport->tcp_reclen - transport->tcp_offset;
1169         if (len > desc->count)
1170                 len = desc->count;
1171         desc->count -= len;
1172         desc->offset += len;
1173         transport->tcp_offset += len;
1174         dprintk("RPC:       discarded %Zu bytes\n", len);
1175         xs_tcp_check_fraghdr(transport);
1176 }
1177
1178 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1179 {
1180         struct rpc_xprt *xprt = rd_desc->arg.data;
1181         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1182         struct xdr_skb_reader desc = {
1183                 .skb    = skb,
1184                 .offset = offset,
1185                 .count  = len,
1186         };
1187
1188         dprintk("RPC:       xs_tcp_data_recv started\n");
1189         do {
1190                 /* Read in a new fragment marker if necessary */
1191                 /* Can we ever really expect to get completely empty fragments? */
1192                 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1193                         xs_tcp_read_fraghdr(xprt, &desc);
1194                         continue;
1195                 }
1196                 /* Read in the xid if necessary */
1197                 if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1198                         xs_tcp_read_xid(transport, &desc);
1199                         continue;
1200                 }
1201                 /* Read in the call/reply flag */
1202                 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1203                         xs_tcp_read_calldir(transport, &desc);
1204                         continue;
1205                 }
1206                 /* Read in the request data */
1207                 if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1208                         xs_tcp_read_data(xprt, &desc);
1209                         continue;
1210                 }
1211                 /* Skip over any trailing bytes on short reads */
1212                 xs_tcp_read_discard(transport, &desc);
1213         } while (desc.count);
1214         dprintk("RPC:       xs_tcp_data_recv done\n");
1215         return len - desc.count;
1216 }
1217
1218 /**
1219  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1220  * @sk: socket with data to read
1221  * @bytes: how much data to read
1222  *
1223  */
1224 static void xs_tcp_data_ready(struct sock *sk, int bytes)
1225 {
1226         struct rpc_xprt *xprt;
1227         read_descriptor_t rd_desc;
1228         int read;
1229
1230         dprintk("RPC:       xs_tcp_data_ready...\n");
1231
1232         read_lock_bh(&sk->sk_callback_lock);
1233         if (!(xprt = xprt_from_sock(sk)))
1234                 goto out;
1235         if (xprt->shutdown)
1236                 goto out;
1237
1238         /* Any data means we had a useful conversation, so
1239          * the we don't need to delay the next reconnect
1240          */
1241         if (xprt->reestablish_timeout)
1242                 xprt->reestablish_timeout = 0;
1243
1244         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1245         rd_desc.arg.data = xprt;
1246         do {
1247                 rd_desc.count = 65536;
1248                 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1249         } while (read > 0);
1250 out:
1251         read_unlock_bh(&sk->sk_callback_lock);
1252 }
1253
1254 /*
1255  * Do the equivalent of linger/linger2 handling for dealing with
1256  * broken servers that don't close the socket in a timely
1257  * fashion
1258  */
1259 static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1260                 unsigned long timeout)
1261 {
1262         struct sock_xprt *transport;
1263
1264         if (xprt_test_and_set_connecting(xprt))
1265                 return;
1266         set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1267         transport = container_of(xprt, struct sock_xprt, xprt);
1268         queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1269                            timeout);
1270 }
1271
1272 static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1273 {
1274         struct sock_xprt *transport;
1275
1276         transport = container_of(xprt, struct sock_xprt, xprt);
1277
1278         if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1279             !cancel_delayed_work(&transport->connect_worker))
1280                 return;
1281         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1282         xprt_clear_connecting(xprt);
1283 }
1284
1285 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1286 {
1287         smp_mb__before_clear_bit();
1288         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1289         clear_bit(XPRT_CLOSING, &xprt->state);
1290         smp_mb__after_clear_bit();
1291         /* Mark transport as closed and wake up all pending tasks */
1292         xprt_disconnect_done(xprt);
1293 }
1294
1295 /**
1296  * xs_tcp_state_change - callback to handle TCP socket state changes
1297  * @sk: socket whose state has changed
1298  *
1299  */
1300 static void xs_tcp_state_change(struct sock *sk)
1301 {
1302         struct rpc_xprt *xprt;
1303
1304         read_lock_bh(&sk->sk_callback_lock);
1305         if (!(xprt = xprt_from_sock(sk)))
1306                 goto out;
1307         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1308         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1309                         sk->sk_state, xprt_connected(xprt),
1310                         sock_flag(sk, SOCK_DEAD),
1311                         sock_flag(sk, SOCK_ZAPPED),
1312                         sk->sk_shutdown);
1313
1314         switch (sk->sk_state) {
1315         case TCP_ESTABLISHED:
1316                 spin_lock(&xprt->transport_lock);
1317                 if (!xprt_test_and_set_connected(xprt)) {
1318                         struct sock_xprt *transport = container_of(xprt,
1319                                         struct sock_xprt, xprt);
1320
1321                         /* Reset TCP record info */
1322                         transport->tcp_offset = 0;
1323                         transport->tcp_reclen = 0;
1324                         transport->tcp_copied = 0;
1325                         transport->tcp_flags =
1326                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1327
1328                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1329                 }
1330                 spin_unlock(&xprt->transport_lock);
1331                 break;
1332         case TCP_FIN_WAIT1:
1333                 /* The client initiated a shutdown of the socket */
1334                 xprt->connect_cookie++;
1335                 xprt->reestablish_timeout = 0;
1336                 set_bit(XPRT_CLOSING, &xprt->state);
1337                 smp_mb__before_clear_bit();
1338                 clear_bit(XPRT_CONNECTED, &xprt->state);
1339                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1340                 smp_mb__after_clear_bit();
1341                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1342                 break;
1343         case TCP_CLOSE_WAIT:
1344                 /* The server initiated a shutdown of the socket */
1345                 xprt_force_disconnect(xprt);
1346         case TCP_SYN_SENT:
1347                 xprt->connect_cookie++;
1348         case TCP_CLOSING:
1349                 /*
1350                  * If the server closed down the connection, make sure that
1351                  * we back off before reconnecting
1352                  */
1353                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1354                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1355                 break;
1356         case TCP_LAST_ACK:
1357                 set_bit(XPRT_CLOSING, &xprt->state);
1358                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1359                 smp_mb__before_clear_bit();
1360                 clear_bit(XPRT_CONNECTED, &xprt->state);
1361                 smp_mb__after_clear_bit();
1362                 break;
1363         case TCP_CLOSE:
1364                 xs_tcp_cancel_linger_timeout(xprt);
1365                 xs_sock_mark_closed(xprt);
1366         }
1367  out:
1368         read_unlock_bh(&sk->sk_callback_lock);
1369 }
1370
1371 /**
1372  * xs_error_report - callback mainly for catching socket errors
1373  * @sk: socket
1374  */
1375 static void xs_error_report(struct sock *sk)
1376 {
1377         struct rpc_xprt *xprt;
1378
1379         read_lock_bh(&sk->sk_callback_lock);
1380         if (!(xprt = xprt_from_sock(sk)))
1381                 goto out;
1382         dprintk("RPC:       %s client %p...\n"
1383                         "RPC:       error %d\n",
1384                         __func__, xprt, sk->sk_err);
1385         xprt_wake_pending_tasks(xprt, -EAGAIN);
1386 out:
1387         read_unlock_bh(&sk->sk_callback_lock);
1388 }
1389
1390 static void xs_write_space(struct sock *sk)
1391 {
1392         struct socket *sock;
1393         struct rpc_xprt *xprt;
1394
1395         if (unlikely(!(sock = sk->sk_socket)))
1396                 return;
1397         clear_bit(SOCK_NOSPACE, &sock->flags);
1398
1399         if (unlikely(!(xprt = xprt_from_sock(sk))))
1400                 return;
1401         if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1402                 return;
1403
1404         xprt_write_space(xprt);
1405 }
1406
1407 /**
1408  * xs_udp_write_space - callback invoked when socket buffer space
1409  *                             becomes available
1410  * @sk: socket whose state has changed
1411  *
1412  * Called when more output buffer space is available for this socket.
1413  * We try not to wake our writers until they can make "significant"
1414  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1415  * with a bunch of small requests.
1416  */
1417 static void xs_udp_write_space(struct sock *sk)
1418 {
1419         read_lock_bh(&sk->sk_callback_lock);
1420
1421         /* from net/core/sock.c:sock_def_write_space */
1422         if (sock_writeable(sk))
1423                 xs_write_space(sk);
1424
1425         read_unlock_bh(&sk->sk_callback_lock);
1426 }
1427
1428 /**
1429  * xs_tcp_write_space - callback invoked when socket buffer space
1430  *                             becomes available
1431  * @sk: socket whose state has changed
1432  *
1433  * Called when more output buffer space is available for this socket.
1434  * We try not to wake our writers until they can make "significant"
1435  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1436  * with a bunch of small requests.
1437  */
1438 static void xs_tcp_write_space(struct sock *sk)
1439 {
1440         read_lock_bh(&sk->sk_callback_lock);
1441
1442         /* from net/core/stream.c:sk_stream_write_space */
1443         if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
1444                 xs_write_space(sk);
1445
1446         read_unlock_bh(&sk->sk_callback_lock);
1447 }
1448
1449 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1450 {
1451         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1452         struct sock *sk = transport->inet;
1453
1454         if (transport->rcvsize) {
1455                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1456                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1457         }
1458         if (transport->sndsize) {
1459                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1460                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1461                 sk->sk_write_space(sk);
1462         }
1463 }
1464
1465 /**
1466  * xs_udp_set_buffer_size - set send and receive limits
1467  * @xprt: generic transport
1468  * @sndsize: requested size of send buffer, in bytes
1469  * @rcvsize: requested size of receive buffer, in bytes
1470  *
1471  * Set socket send and receive buffer size limits.
1472  */
1473 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1474 {
1475         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1476
1477         transport->sndsize = 0;
1478         if (sndsize)
1479                 transport->sndsize = sndsize + 1024;
1480         transport->rcvsize = 0;
1481         if (rcvsize)
1482                 transport->rcvsize = rcvsize + 1024;
1483
1484         xs_udp_do_set_buffer_size(xprt);
1485 }
1486
1487 /**
1488  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1489  * @task: task that timed out
1490  *
1491  * Adjust the congestion window after a retransmit timeout has occurred.
1492  */
1493 static void xs_udp_timer(struct rpc_task *task)
1494 {
1495         xprt_adjust_cwnd(task, -ETIMEDOUT);
1496 }
1497
1498 static unsigned short xs_get_random_port(void)
1499 {
1500         unsigned short range = xprt_max_resvport - xprt_min_resvport;
1501         unsigned short rand = (unsigned short) net_random() % range;
1502         return rand + xprt_min_resvport;
1503 }
1504
1505 /**
1506  * xs_set_port - reset the port number in the remote endpoint address
1507  * @xprt: generic transport
1508  * @port: new port number
1509  *
1510  */
1511 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1512 {
1513         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1514
1515         rpc_set_port(xs_addr(xprt), port);
1516         xs_update_peer_port(xprt);
1517 }
1518
1519 static unsigned short xs_get_srcport(struct sock_xprt *transport, struct socket *sock)
1520 {
1521         unsigned short port = transport->srcport;
1522
1523         if (port == 0 && transport->xprt.resvport)
1524                 port = xs_get_random_port();
1525         return port;
1526 }
1527
1528 static unsigned short xs_next_srcport(struct sock_xprt *transport, struct socket *sock, unsigned short port)
1529 {
1530         if (transport->srcport != 0)
1531                 transport->srcport = 0;
1532         if (!transport->xprt.resvport)
1533                 return 0;
1534         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1535                 return xprt_max_resvport;
1536         return --port;
1537 }
1538
1539 static int xs_bind4(struct sock_xprt *transport, struct socket *sock)
1540 {
1541         struct sockaddr_in myaddr = {
1542                 .sin_family = AF_INET,
1543         };
1544         struct sockaddr_in *sa;
1545         int err, nloop = 0;
1546         unsigned short port = xs_get_srcport(transport, sock);
1547         unsigned short last;
1548
1549         sa = (struct sockaddr_in *)&transport->srcaddr;
1550         myaddr.sin_addr = sa->sin_addr;
1551         do {
1552                 myaddr.sin_port = htons(port);
1553                 err = kernel_bind(sock, (struct sockaddr *) &myaddr,
1554                                                 sizeof(myaddr));
1555                 if (port == 0)
1556                         break;
1557                 if (err == 0) {
1558                         transport->srcport = port;
1559                         break;
1560                 }
1561                 last = port;
1562                 port = xs_next_srcport(transport, sock, port);
1563                 if (port > last)
1564                         nloop++;
1565         } while (err == -EADDRINUSE && nloop != 2);
1566         dprintk("RPC:       %s %pI4:%u: %s (%d)\n",
1567                         __func__, &myaddr.sin_addr,
1568                         port, err ? "failed" : "ok", err);
1569         return err;
1570 }
1571
1572 static int xs_bind6(struct sock_xprt *transport, struct socket *sock)
1573 {
1574         struct sockaddr_in6 myaddr = {
1575                 .sin6_family = AF_INET6,
1576         };
1577         struct sockaddr_in6 *sa;
1578         int err, nloop = 0;
1579         unsigned short port = xs_get_srcport(transport, sock);
1580         unsigned short last;
1581
1582         sa = (struct sockaddr_in6 *)&transport->srcaddr;
1583         myaddr.sin6_addr = sa->sin6_addr;
1584         do {
1585                 myaddr.sin6_port = htons(port);
1586                 err = kernel_bind(sock, (struct sockaddr *) &myaddr,
1587                                                 sizeof(myaddr));
1588                 if (port == 0)
1589                         break;
1590                 if (err == 0) {
1591                         transport->srcport = port;
1592                         break;
1593                 }
1594                 last = port;
1595                 port = xs_next_srcport(transport, sock, port);
1596                 if (port > last)
1597                         nloop++;
1598         } while (err == -EADDRINUSE && nloop != 2);
1599         dprintk("RPC:       xs_bind6 %pI6:%u: %s (%d)\n",
1600                 &myaddr.sin6_addr, port, err ? "failed" : "ok", err);
1601         return err;
1602 }
1603
1604 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1605 static struct lock_class_key xs_key[2];
1606 static struct lock_class_key xs_slock_key[2];
1607
1608 static inline void xs_reclassify_socket4(struct socket *sock)
1609 {
1610         struct sock *sk = sock->sk;
1611
1612         BUG_ON(sock_owned_by_user(sk));
1613         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1614                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1615 }
1616
1617 static inline void xs_reclassify_socket6(struct socket *sock)
1618 {
1619         struct sock *sk = sock->sk;
1620
1621         BUG_ON(sock_owned_by_user(sk));
1622         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1623                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1624 }
1625 #else
1626 static inline void xs_reclassify_socket4(struct socket *sock)
1627 {
1628 }
1629
1630 static inline void xs_reclassify_socket6(struct socket *sock)
1631 {
1632 }
1633 #endif
1634
1635 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1636 {
1637         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1638
1639         if (!transport->inet) {
1640                 struct sock *sk = sock->sk;
1641
1642                 write_lock_bh(&sk->sk_callback_lock);
1643
1644                 xs_save_old_callbacks(transport, sk);
1645
1646                 sk->sk_user_data = xprt;
1647                 sk->sk_data_ready = xs_udp_data_ready;
1648                 sk->sk_write_space = xs_udp_write_space;
1649                 sk->sk_error_report = xs_error_report;
1650                 sk->sk_no_check = UDP_CSUM_NORCV;
1651                 sk->sk_allocation = GFP_ATOMIC;
1652
1653                 xprt_set_connected(xprt);
1654
1655                 /* Reset to new socket */
1656                 transport->sock = sock;
1657                 transport->inet = sk;
1658
1659                 write_unlock_bh(&sk->sk_callback_lock);
1660         }
1661         xs_udp_do_set_buffer_size(xprt);
1662 }
1663
1664 /**
1665  * xs_udp_connect_worker4 - set up a UDP socket
1666  * @work: RPC transport to connect
1667  *
1668  * Invoked by a work queue tasklet.
1669  */
1670 static void xs_udp_connect_worker4(struct work_struct *work)
1671 {
1672         struct sock_xprt *transport =
1673                 container_of(work, struct sock_xprt, connect_worker.work);
1674         struct rpc_xprt *xprt = &transport->xprt;
1675         struct socket *sock = transport->sock;
1676         int err, status = -EIO;
1677
1678         if (xprt->shutdown)
1679                 goto out;
1680
1681         /* Start by resetting any existing state */
1682         xs_reset_transport(transport);
1683
1684         err = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1685         if (err < 0) {
1686                 dprintk("RPC:       can't create UDP transport socket (%d).\n", -err);
1687                 goto out;
1688         }
1689         xs_reclassify_socket4(sock);
1690
1691         if (xs_bind4(transport, sock)) {
1692                 sock_release(sock);
1693                 goto out;
1694         }
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  * xs_udp_connect_worker6 - set up a UDP socket
1711  * @work: RPC transport to connect
1712  *
1713  * Invoked by a work queue tasklet.
1714  */
1715 static void xs_udp_connect_worker6(struct work_struct *work)
1716 {
1717         struct sock_xprt *transport =
1718                 container_of(work, struct sock_xprt, connect_worker.work);
1719         struct rpc_xprt *xprt = &transport->xprt;
1720         struct socket *sock = transport->sock;
1721         int err, status = -EIO;
1722
1723         if (xprt->shutdown)
1724                 goto out;
1725
1726         /* Start by resetting any existing state */
1727         xs_reset_transport(transport);
1728
1729         err = sock_create_kern(PF_INET6, SOCK_DGRAM, IPPROTO_UDP, &sock);
1730         if (err < 0) {
1731                 dprintk("RPC:       can't create UDP transport socket (%d).\n", -err);
1732                 goto out;
1733         }
1734         xs_reclassify_socket6(sock);
1735
1736         if (xs_bind6(transport, sock) < 0) {
1737                 sock_release(sock);
1738                 goto out;
1739         }
1740
1741         dprintk("RPC:       worker connecting xprt %p via %s to "
1742                                 "%s (port %s)\n", xprt,
1743                         xprt->address_strings[RPC_DISPLAY_PROTO],
1744                         xprt->address_strings[RPC_DISPLAY_ADDR],
1745                         xprt->address_strings[RPC_DISPLAY_PORT]);
1746
1747         xs_udp_finish_connecting(xprt, sock);
1748         status = 0;
1749 out:
1750         xprt_clear_connecting(xprt);
1751         xprt_wake_pending_tasks(xprt, status);
1752 }
1753
1754 /*
1755  * We need to preserve the port number so the reply cache on the server can
1756  * find our cached RPC replies when we get around to reconnecting.
1757  */
1758 static void xs_abort_connection(struct rpc_xprt *xprt, struct sock_xprt *transport)
1759 {
1760         int result;
1761         struct sockaddr any;
1762
1763         dprintk("RPC:       disconnecting xprt %p to reuse port\n", xprt);
1764
1765         /*
1766          * Disconnect the transport socket by doing a connect operation
1767          * with AF_UNSPEC.  This should return immediately...
1768          */
1769         memset(&any, 0, sizeof(any));
1770         any.sa_family = AF_UNSPEC;
1771         result = kernel_connect(transport->sock, &any, sizeof(any), 0);
1772         if (!result)
1773                 xs_sock_mark_closed(xprt);
1774         else
1775                 dprintk("RPC:       AF_UNSPEC connect return code %d\n",
1776                                 result);
1777 }
1778
1779 static void xs_tcp_reuse_connection(struct rpc_xprt *xprt, struct sock_xprt *transport)
1780 {
1781         unsigned int state = transport->inet->sk_state;
1782
1783         if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
1784                 /* we don't need to abort the connection if the socket
1785                  * hasn't undergone a shutdown
1786                  */
1787                 if (transport->inet->sk_shutdown == 0)
1788                         return;
1789                 dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
1790                                 __func__, transport->inet->sk_shutdown);
1791         }
1792         if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
1793                 /* we don't need to abort the connection if the socket
1794                  * hasn't undergone a shutdown
1795                  */
1796                 if (transport->inet->sk_shutdown == 0)
1797                         return;
1798                 dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
1799                                 "sk_shutdown set to %d\n",
1800                                 __func__, transport->inet->sk_shutdown);
1801         }
1802         xs_abort_connection(xprt, transport);
1803 }
1804
1805 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
1806 {
1807         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1808
1809         if (!transport->inet) {
1810                 struct sock *sk = sock->sk;
1811
1812                 write_lock_bh(&sk->sk_callback_lock);
1813
1814                 xs_save_old_callbacks(transport, sk);
1815
1816                 sk->sk_user_data = xprt;
1817                 sk->sk_data_ready = xs_tcp_data_ready;
1818                 sk->sk_state_change = xs_tcp_state_change;
1819                 sk->sk_write_space = xs_tcp_write_space;
1820                 sk->sk_error_report = xs_error_report;
1821                 sk->sk_allocation = GFP_ATOMIC;
1822
1823                 /* socket options */
1824                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
1825                 sock_reset_flag(sk, SOCK_LINGER);
1826                 tcp_sk(sk)->linger2 = 0;
1827                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
1828
1829                 xprt_clear_connected(xprt);
1830
1831                 /* Reset to new socket */
1832                 transport->sock = sock;
1833                 transport->inet = sk;
1834
1835                 write_unlock_bh(&sk->sk_callback_lock);
1836         }
1837
1838         if (!xprt_bound(xprt))
1839                 return -ENOTCONN;
1840
1841         /* Tell the socket layer to start connecting... */
1842         xprt->stat.connect_count++;
1843         xprt->stat.connect_start = jiffies;
1844         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
1845 }
1846
1847 /**
1848  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
1849  * @xprt: RPC transport to connect
1850  * @transport: socket transport to connect
1851  * @create_sock: function to create a socket of the correct type
1852  *
1853  * Invoked by a work queue tasklet.
1854  */
1855 static void xs_tcp_setup_socket(struct rpc_xprt *xprt,
1856                 struct sock_xprt *transport,
1857                 struct socket *(*create_sock)(struct rpc_xprt *,
1858                         struct sock_xprt *))
1859 {
1860         struct socket *sock = transport->sock;
1861         int status = -EIO;
1862
1863         if (xprt->shutdown)
1864                 goto out;
1865
1866         if (!sock) {
1867                 clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1868                 sock = create_sock(xprt, transport);
1869                 if (IS_ERR(sock)) {
1870                         status = PTR_ERR(sock);
1871                         goto out;
1872                 }
1873         } else {
1874                 int abort_and_exit;
1875
1876                 abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
1877                                 &xprt->state);
1878                 /* "close" the socket, preserving the local port */
1879                 xs_tcp_reuse_connection(xprt, transport);
1880
1881                 if (abort_and_exit)
1882                         goto out_eagain;
1883         }
1884
1885         dprintk("RPC:       worker connecting xprt %p via %s to "
1886                                 "%s (port %s)\n", xprt,
1887                         xprt->address_strings[RPC_DISPLAY_PROTO],
1888                         xprt->address_strings[RPC_DISPLAY_ADDR],
1889                         xprt->address_strings[RPC_DISPLAY_PORT]);
1890
1891         status = xs_tcp_finish_connecting(xprt, sock);
1892         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
1893                         xprt, -status, xprt_connected(xprt),
1894                         sock->sk->sk_state);
1895         switch (status) {
1896         default:
1897                 printk("%s: connect returned unhandled error %d\n",
1898                         __func__, status);
1899         case -EADDRNOTAVAIL:
1900                 /* We're probably in TIME_WAIT. Get rid of existing socket,
1901                  * and retry
1902                  */
1903                 set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1904                 xprt_force_disconnect(xprt);
1905                 break;
1906         case -ECONNREFUSED:
1907         case -ECONNRESET:
1908         case -ENETUNREACH:
1909                 /* retry with existing socket, after a delay */
1910         case 0:
1911         case -EINPROGRESS:
1912         case -EALREADY:
1913                 xprt_clear_connecting(xprt);
1914                 return;
1915         case -EINVAL:
1916                 /* Happens, for instance, if the user specified a link
1917                  * local IPv6 address without a scope-id.
1918                  */
1919                 goto out;
1920         }
1921 out_eagain:
1922         status = -EAGAIN;
1923 out:
1924         xprt_clear_connecting(xprt);
1925         xprt_wake_pending_tasks(xprt, status);
1926 }
1927
1928 static struct socket *xs_create_tcp_sock4(struct rpc_xprt *xprt,
1929                 struct sock_xprt *transport)
1930 {
1931         struct socket *sock;
1932         int err;
1933
1934         /* start from scratch */
1935         err = sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
1936         if (err < 0) {
1937                 dprintk("RPC:       can't create TCP transport socket (%d).\n",
1938                                 -err);
1939                 goto out_err;
1940         }
1941         xs_reclassify_socket4(sock);
1942
1943         if (xs_bind4(transport, sock) < 0) {
1944                 sock_release(sock);
1945                 goto out_err;
1946         }
1947         return sock;
1948 out_err:
1949         return ERR_PTR(-EIO);
1950 }
1951
1952 /**
1953  * xs_tcp_connect_worker4 - connect a TCP socket to a remote endpoint
1954  * @work: RPC transport to connect
1955  *
1956  * Invoked by a work queue tasklet.
1957  */
1958 static void xs_tcp_connect_worker4(struct work_struct *work)
1959 {
1960         struct sock_xprt *transport =
1961                 container_of(work, struct sock_xprt, connect_worker.work);
1962         struct rpc_xprt *xprt = &transport->xprt;
1963
1964         xs_tcp_setup_socket(xprt, transport, xs_create_tcp_sock4);
1965 }
1966
1967 static struct socket *xs_create_tcp_sock6(struct rpc_xprt *xprt,
1968                 struct sock_xprt *transport)
1969 {
1970         struct socket *sock;
1971         int err;
1972
1973         /* start from scratch */
1974         err = sock_create_kern(PF_INET6, SOCK_STREAM, IPPROTO_TCP, &sock);
1975         if (err < 0) {
1976                 dprintk("RPC:       can't create TCP transport socket (%d).\n",
1977                                 -err);
1978                 goto out_err;
1979         }
1980         xs_reclassify_socket6(sock);
1981
1982         if (xs_bind6(transport, sock) < 0) {
1983                 sock_release(sock);
1984                 goto out_err;
1985         }
1986         return sock;
1987 out_err:
1988         return ERR_PTR(-EIO);
1989 }
1990
1991 /**
1992  * xs_tcp_connect_worker6 - connect a TCP socket to a remote endpoint
1993  * @work: RPC transport to connect
1994  *
1995  * Invoked by a work queue tasklet.
1996  */
1997 static void xs_tcp_connect_worker6(struct work_struct *work)
1998 {
1999         struct sock_xprt *transport =
2000                 container_of(work, struct sock_xprt, connect_worker.work);
2001         struct rpc_xprt *xprt = &transport->xprt;
2002
2003         xs_tcp_setup_socket(xprt, transport, xs_create_tcp_sock6);
2004 }
2005
2006 /**
2007  * xs_connect - connect a socket to a remote endpoint
2008  * @task: address of RPC task that manages state of connect request
2009  *
2010  * TCP: If the remote end dropped the connection, delay reconnecting.
2011  *
2012  * UDP socket connects are synchronous, but we use a work queue anyway
2013  * to guarantee that even unprivileged user processes can set up a
2014  * socket on a privileged port.
2015  *
2016  * If a UDP socket connect fails, the delay behavior here prevents
2017  * retry floods (hard mounts).
2018  */
2019 static void xs_connect(struct rpc_task *task)
2020 {
2021         struct rpc_xprt *xprt = task->tk_xprt;
2022         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2023
2024         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
2025                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2026                                 "seconds\n",
2027                                 xprt, xprt->reestablish_timeout / HZ);
2028                 queue_delayed_work(rpciod_workqueue,
2029                                    &transport->connect_worker,
2030                                    xprt->reestablish_timeout);
2031                 xprt->reestablish_timeout <<= 1;
2032                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2033                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2034                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
2035                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
2036         } else {
2037                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2038                 queue_delayed_work(rpciod_workqueue,
2039                                    &transport->connect_worker, 0);
2040         }
2041 }
2042
2043 /**
2044  * xs_udp_print_stats - display UDP socket-specifc stats
2045  * @xprt: rpc_xprt struct containing statistics
2046  * @seq: output file
2047  *
2048  */
2049 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2050 {
2051         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2052
2053         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
2054                         transport->srcport,
2055                         xprt->stat.bind_count,
2056                         xprt->stat.sends,
2057                         xprt->stat.recvs,
2058                         xprt->stat.bad_xids,
2059                         xprt->stat.req_u,
2060                         xprt->stat.bklog_u);
2061 }
2062
2063 /**
2064  * xs_tcp_print_stats - display TCP socket-specifc stats
2065  * @xprt: rpc_xprt struct containing statistics
2066  * @seq: output file
2067  *
2068  */
2069 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2070 {
2071         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2072         long idle_time = 0;
2073
2074         if (xprt_connected(xprt))
2075                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2076
2077         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
2078                         transport->srcport,
2079                         xprt->stat.bind_count,
2080                         xprt->stat.connect_count,
2081                         xprt->stat.connect_time,
2082                         idle_time,
2083                         xprt->stat.sends,
2084                         xprt->stat.recvs,
2085                         xprt->stat.bad_xids,
2086                         xprt->stat.req_u,
2087                         xprt->stat.bklog_u);
2088 }
2089
2090 /*
2091  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2092  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2093  * to use the server side send routines.
2094  */
2095 static void *bc_malloc(struct rpc_task *task, size_t size)
2096 {
2097         struct page *page;
2098         struct rpc_buffer *buf;
2099
2100         BUG_ON(size > PAGE_SIZE - sizeof(struct rpc_buffer));
2101         page = alloc_page(GFP_KERNEL);
2102
2103         if (!page)
2104                 return NULL;
2105
2106         buf = page_address(page);
2107         buf->len = PAGE_SIZE;
2108
2109         return buf->data;
2110 }
2111
2112 /*
2113  * Free the space allocated in the bc_alloc routine
2114  */
2115 static void bc_free(void *buffer)
2116 {
2117         struct rpc_buffer *buf;
2118
2119         if (!buffer)
2120                 return;
2121
2122         buf = container_of(buffer, struct rpc_buffer, data);
2123         free_page((unsigned long)buf);
2124 }
2125
2126 /*
2127  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2128  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2129  */
2130 static int bc_sendto(struct rpc_rqst *req)
2131 {
2132         int len;
2133         struct xdr_buf *xbufp = &req->rq_snd_buf;
2134         struct rpc_xprt *xprt = req->rq_xprt;
2135         struct sock_xprt *transport =
2136                                 container_of(xprt, struct sock_xprt, xprt);
2137         struct socket *sock = transport->sock;
2138         unsigned long headoff;
2139         unsigned long tailoff;
2140
2141         /*
2142          * Set up the rpc header and record marker stuff
2143          */
2144         xs_encode_tcp_record_marker(xbufp);
2145
2146         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2147         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2148         len = svc_send_common(sock, xbufp,
2149                               virt_to_page(xbufp->head[0].iov_base), headoff,
2150                               xbufp->tail[0].iov_base, tailoff);
2151
2152         if (len != xbufp->len) {
2153                 printk(KERN_NOTICE "Error sending entire callback!\n");
2154                 len = -EAGAIN;
2155         }
2156
2157         return len;
2158 }
2159
2160 /*
2161  * The send routine. Borrows from svc_send
2162  */
2163 static int bc_send_request(struct rpc_task *task)
2164 {
2165         struct rpc_rqst *req = task->tk_rqstp;
2166         struct svc_xprt *xprt;
2167         struct svc_sock         *svsk;
2168         u32                     len;
2169
2170         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2171         /*
2172          * Get the server socket associated with this callback xprt
2173          */
2174         xprt = req->rq_xprt->bc_xprt;
2175         svsk = container_of(xprt, struct svc_sock, sk_xprt);
2176
2177         /*
2178          * Grab the mutex to serialize data as the connection is shared
2179          * with the fore channel
2180          */
2181         if (!mutex_trylock(&xprt->xpt_mutex)) {
2182                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2183                 if (!mutex_trylock(&xprt->xpt_mutex))
2184                         return -EAGAIN;
2185                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2186         }
2187         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2188                 len = -ENOTCONN;
2189         else
2190                 len = bc_sendto(req);
2191         mutex_unlock(&xprt->xpt_mutex);
2192
2193         if (len > 0)
2194                 len = 0;
2195
2196         return len;
2197 }
2198
2199 /*
2200  * The close routine. Since this is client initiated, we do nothing
2201  */
2202
2203 static void bc_close(struct rpc_xprt *xprt)
2204 {
2205 }
2206
2207 /*
2208  * The xprt destroy routine. Again, because this connection is client
2209  * initiated, we do nothing
2210  */
2211
2212 static void bc_destroy(struct rpc_xprt *xprt)
2213 {
2214 }
2215
2216 static struct rpc_xprt_ops xs_udp_ops = {
2217         .set_buffer_size        = xs_udp_set_buffer_size,
2218         .reserve_xprt           = xprt_reserve_xprt_cong,
2219         .release_xprt           = xprt_release_xprt_cong,
2220         .rpcbind                = rpcb_getport_async,
2221         .set_port               = xs_set_port,
2222         .connect                = xs_connect,
2223         .buf_alloc              = rpc_malloc,
2224         .buf_free               = rpc_free,
2225         .send_request           = xs_udp_send_request,
2226         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2227         .timer                  = xs_udp_timer,
2228         .release_request        = xprt_release_rqst_cong,
2229         .close                  = xs_close,
2230         .destroy                = xs_destroy,
2231         .print_stats            = xs_udp_print_stats,
2232 };
2233
2234 static struct rpc_xprt_ops xs_tcp_ops = {
2235         .reserve_xprt           = xprt_reserve_xprt,
2236         .release_xprt           = xs_tcp_release_xprt,
2237         .rpcbind                = rpcb_getport_async,
2238         .set_port               = xs_set_port,
2239         .connect                = xs_connect,
2240         .buf_alloc              = rpc_malloc,
2241         .buf_free               = rpc_free,
2242         .send_request           = xs_tcp_send_request,
2243         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2244         .close                  = xs_tcp_close,
2245         .destroy                = xs_destroy,
2246         .print_stats            = xs_tcp_print_stats,
2247 };
2248
2249 /*
2250  * The rpc_xprt_ops for the server backchannel
2251  */
2252
2253 static struct rpc_xprt_ops bc_tcp_ops = {
2254         .reserve_xprt           = xprt_reserve_xprt,
2255         .release_xprt           = xprt_release_xprt,
2256         .buf_alloc              = bc_malloc,
2257         .buf_free               = bc_free,
2258         .send_request           = bc_send_request,
2259         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2260         .close                  = bc_close,
2261         .destroy                = bc_destroy,
2262         .print_stats            = xs_tcp_print_stats,
2263 };
2264
2265 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2266                                       unsigned int slot_table_size)
2267 {
2268         struct rpc_xprt *xprt;
2269         struct sock_xprt *new;
2270
2271         if (args->addrlen > sizeof(xprt->addr)) {
2272                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2273                 return ERR_PTR(-EBADF);
2274         }
2275
2276         new = kzalloc(sizeof(*new), GFP_KERNEL);
2277         if (new == NULL) {
2278                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2279                                 "rpc_xprt\n");
2280                 return ERR_PTR(-ENOMEM);
2281         }
2282         xprt = &new->xprt;
2283
2284         xprt->max_reqs = slot_table_size;
2285         xprt->slot = kcalloc(xprt->max_reqs, sizeof(struct rpc_rqst), GFP_KERNEL);
2286         if (xprt->slot == NULL) {
2287                 kfree(xprt);
2288                 dprintk("RPC:       xs_setup_xprt: couldn't allocate slot "
2289                                 "table\n");
2290                 return ERR_PTR(-ENOMEM);
2291         }
2292
2293         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2294         xprt->addrlen = args->addrlen;
2295         if (args->srcaddr)
2296                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2297
2298         return xprt;
2299 }
2300
2301 static const struct rpc_timeout xs_udp_default_timeout = {
2302         .to_initval = 5 * HZ,
2303         .to_maxval = 30 * HZ,
2304         .to_increment = 5 * HZ,
2305         .to_retries = 5,
2306 };
2307
2308 /**
2309  * xs_setup_udp - Set up transport to use a UDP socket
2310  * @args: rpc transport creation arguments
2311  *
2312  */
2313 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2314 {
2315         struct sockaddr *addr = args->dstaddr;
2316         struct rpc_xprt *xprt;
2317         struct sock_xprt *transport;
2318         struct rpc_xprt *ret;
2319
2320         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries);
2321         if (IS_ERR(xprt))
2322                 return xprt;
2323         transport = container_of(xprt, struct sock_xprt, xprt);
2324
2325         xprt->prot = IPPROTO_UDP;
2326         xprt->tsh_size = 0;
2327         /* XXX: header size can vary due to auth type, IPv6, etc. */
2328         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2329
2330         xprt->bind_timeout = XS_BIND_TO;
2331         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2332         xprt->idle_timeout = XS_IDLE_DISC_TO;
2333
2334         xprt->ops = &xs_udp_ops;
2335
2336         xprt->timeout = &xs_udp_default_timeout;
2337
2338         switch (addr->sa_family) {
2339         case AF_INET:
2340                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2341                         xprt_set_bound(xprt);
2342
2343                 INIT_DELAYED_WORK(&transport->connect_worker,
2344                                         xs_udp_connect_worker4);
2345                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2346                 break;
2347         case AF_INET6:
2348                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2349                         xprt_set_bound(xprt);
2350
2351                 INIT_DELAYED_WORK(&transport->connect_worker,
2352                                         xs_udp_connect_worker6);
2353                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2354                 break;
2355         default:
2356                 ret = ERR_PTR(-EAFNOSUPPORT);
2357                 goto out_err;
2358         }
2359
2360         if (xprt_bound(xprt))
2361                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2362                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2363                                 xprt->address_strings[RPC_DISPLAY_PORT],
2364                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2365         else
2366                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2367                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2368                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2369
2370         if (try_module_get(THIS_MODULE))
2371                 return xprt;
2372         ret = ERR_PTR(-EINVAL);
2373 out_err:
2374         kfree(xprt->slot);
2375         kfree(xprt);
2376         return ret;
2377 }
2378
2379 static const struct rpc_timeout xs_tcp_default_timeout = {
2380         .to_initval = 60 * HZ,
2381         .to_maxval = 60 * HZ,
2382         .to_retries = 2,
2383 };
2384
2385 /**
2386  * xs_setup_tcp - Set up transport to use a TCP socket
2387  * @args: rpc transport creation arguments
2388  *
2389  */
2390 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2391 {
2392         struct sockaddr *addr = args->dstaddr;
2393         struct rpc_xprt *xprt;
2394         struct sock_xprt *transport;
2395         struct rpc_xprt *ret;
2396
2397         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2398         if (IS_ERR(xprt))
2399                 return xprt;
2400         transport = container_of(xprt, struct sock_xprt, xprt);
2401
2402         xprt->prot = IPPROTO_TCP;
2403         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2404         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2405
2406         xprt->bind_timeout = XS_BIND_TO;
2407         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2408         xprt->idle_timeout = XS_IDLE_DISC_TO;
2409
2410         xprt->ops = &xs_tcp_ops;
2411         xprt->timeout = &xs_tcp_default_timeout;
2412
2413         switch (addr->sa_family) {
2414         case AF_INET:
2415                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2416                         xprt_set_bound(xprt);
2417
2418                 INIT_DELAYED_WORK(&transport->connect_worker,
2419                                         xs_tcp_connect_worker4);
2420                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2421                 break;
2422         case AF_INET6:
2423                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2424                         xprt_set_bound(xprt);
2425
2426                 INIT_DELAYED_WORK(&transport->connect_worker,
2427                                         xs_tcp_connect_worker6);
2428                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2429                 break;
2430         default:
2431                 ret = ERR_PTR(-EAFNOSUPPORT);
2432                 goto out_err;
2433         }
2434
2435         if (xprt_bound(xprt))
2436                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2437                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2438                                 xprt->address_strings[RPC_DISPLAY_PORT],
2439                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2440         else
2441                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2442                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2443                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2444
2445
2446         if (try_module_get(THIS_MODULE))
2447                 return xprt;
2448         ret = ERR_PTR(-EINVAL);
2449 out_err:
2450         kfree(xprt->slot);
2451         kfree(xprt);
2452         return ret;
2453 }
2454
2455 /**
2456  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2457  * @args: rpc transport creation arguments
2458  *
2459  */
2460 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2461 {
2462         struct sockaddr *addr = args->dstaddr;
2463         struct rpc_xprt *xprt;
2464         struct sock_xprt *transport;
2465         struct svc_sock *bc_sock;
2466         struct rpc_xprt *ret;
2467
2468         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
2469         if (IS_ERR(xprt))
2470                 return xprt;
2471         transport = container_of(xprt, struct sock_xprt, xprt);
2472
2473         xprt->prot = IPPROTO_TCP;
2474         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2475         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2476         xprt->timeout = &xs_tcp_default_timeout;
2477
2478         /* backchannel */
2479         xprt_set_bound(xprt);
2480         xprt->bind_timeout = 0;
2481         xprt->reestablish_timeout = 0;
2482         xprt->idle_timeout = 0;
2483
2484         /*
2485          * The backchannel uses the same socket connection as the
2486          * forechannel
2487          */
2488         xprt->bc_xprt = args->bc_xprt;
2489         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2490         bc_sock->sk_bc_xprt = xprt;
2491         transport->sock = bc_sock->sk_sock;
2492         transport->inet = bc_sock->sk_sk;
2493
2494         xprt->ops = &bc_tcp_ops;
2495
2496         switch (addr->sa_family) {
2497         case AF_INET:
2498                 xs_format_peer_addresses(xprt, "tcp",
2499                                          RPCBIND_NETID_TCP);
2500                 break;
2501         case AF_INET6:
2502                 xs_format_peer_addresses(xprt, "tcp",
2503                                    RPCBIND_NETID_TCP6);
2504                 break;
2505         default:
2506                 ret = ERR_PTR(-EAFNOSUPPORT);
2507                 goto out_err;
2508         }
2509
2510         if (xprt_bound(xprt))
2511                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2512                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2513                                 xprt->address_strings[RPC_DISPLAY_PORT],
2514                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2515         else
2516                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2517                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2518                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2519
2520         /*
2521          * Since we don't want connections for the backchannel, we set
2522          * the xprt status to connected
2523          */
2524         xprt_set_connected(xprt);
2525
2526
2527         if (try_module_get(THIS_MODULE))
2528                 return xprt;
2529         ret = ERR_PTR(-EINVAL);
2530 out_err:
2531         kfree(xprt->slot);
2532         kfree(xprt);
2533         return ret;
2534 }
2535
2536 static struct xprt_class        xs_udp_transport = {
2537         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2538         .name           = "udp",
2539         .owner          = THIS_MODULE,
2540         .ident          = XPRT_TRANSPORT_UDP,
2541         .setup          = xs_setup_udp,
2542 };
2543
2544 static struct xprt_class        xs_tcp_transport = {
2545         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
2546         .name           = "tcp",
2547         .owner          = THIS_MODULE,
2548         .ident          = XPRT_TRANSPORT_TCP,
2549         .setup          = xs_setup_tcp,
2550 };
2551
2552 static struct xprt_class        xs_bc_tcp_transport = {
2553         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2554         .name           = "tcp NFSv4.1 backchannel",
2555         .owner          = THIS_MODULE,
2556         .ident          = XPRT_TRANSPORT_BC_TCP,
2557         .setup          = xs_setup_bc_tcp,
2558 };
2559
2560 /**
2561  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
2562  *
2563  */
2564 int init_socket_xprt(void)
2565 {
2566 #ifdef RPC_DEBUG
2567         if (!sunrpc_table_header)
2568                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
2569 #endif
2570
2571         xprt_register_transport(&xs_udp_transport);
2572         xprt_register_transport(&xs_tcp_transport);
2573         xprt_register_transport(&xs_bc_tcp_transport);
2574
2575         return 0;
2576 }
2577
2578 /**
2579  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
2580  *
2581  */
2582 void cleanup_socket_xprt(void)
2583 {
2584 #ifdef RPC_DEBUG
2585         if (sunrpc_table_header) {
2586                 unregister_sysctl_table(sunrpc_table_header);
2587                 sunrpc_table_header = NULL;
2588         }
2589 #endif
2590
2591         xprt_unregister_transport(&xs_udp_transport);
2592         xprt_unregister_transport(&xs_tcp_transport);
2593         xprt_unregister_transport(&xs_bc_tcp_transport);
2594 }
2595
2596 static int param_set_uint_minmax(const char *val,
2597                 const struct kernel_param *kp,
2598                 unsigned int min, unsigned int max)
2599 {
2600         unsigned long num;
2601         int ret;
2602
2603         if (!val)
2604                 return -EINVAL;
2605         ret = strict_strtoul(val, 0, &num);
2606         if (ret == -EINVAL || num < min || num > max)
2607                 return -EINVAL;
2608         *((unsigned int *)kp->arg) = num;
2609         return 0;
2610 }
2611
2612 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2613 {
2614         return param_set_uint_minmax(val, kp,
2615                         RPC_MIN_RESVPORT,
2616                         RPC_MAX_RESVPORT);
2617 }
2618
2619 static struct kernel_param_ops param_ops_portnr = {
2620         .set = param_set_portnr,
2621         .get = param_get_uint,
2622 };
2623
2624 #define param_check_portnr(name, p) \
2625         __param_check(name, p, unsigned int);
2626
2627 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
2628 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
2629
2630 static int param_set_slot_table_size(const char *val,
2631                                      const struct kernel_param *kp)
2632 {
2633         return param_set_uint_minmax(val, kp,
2634                         RPC_MIN_SLOT_TABLE,
2635                         RPC_MAX_SLOT_TABLE);
2636 }
2637
2638 static struct kernel_param_ops param_ops_slot_table_size = {
2639         .set = param_set_slot_table_size,
2640         .get = param_get_uint,
2641 };
2642
2643 #define param_check_slot_table_size(name, p) \
2644         __param_check(name, p, unsigned int);
2645
2646 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
2647                    slot_table_size, 0644);
2648 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
2649                    slot_table_size, 0644);
2650