net/sunrpc/xprtsock.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/net/sunrpc/xprtsock.c
   4  *
   5  * Client-side transport implementation for sockets.
   6  *
   7  * TCP callback races fixes (C) 1998 Red Hat
   8  * TCP send fixes (C) 1998 Red Hat
   9  * TCP NFS related read + write fixes
  10  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11  *
  12  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13  * Fix behaviour when socket buffer is full.
  14  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15  *
  16  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17  *
  18  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19  *   <gilles.quillard@bull.net>
  20  */
  21
  22 #include <linux/types.h>
  23 #include <linux/string.h>
  24 #include <linux/slab.h>
  25 #include <linux/module.h>
  26 #include <linux/capability.h>
  27 #include <linux/pagemap.h>
  28 #include <linux/errno.h>
  29 #include <linux/socket.h>
  30 #include <linux/in.h>
  31 #include <linux/net.h>
  32 #include <linux/mm.h>
  33 #include <linux/un.h>
  34 #include <linux/udp.h>
  35 #include <linux/tcp.h>
  36 #include <linux/sunrpc/clnt.h>
  37 #include <linux/sunrpc/addr.h>
  38 #include <linux/sunrpc/sched.h>
  39 #include <linux/sunrpc/svcsock.h>
  40 #include <linux/sunrpc/xprtsock.h>
  41 #include <linux/file.h>
  42 #ifdef CONFIG_SUNRPC_BACKCHANNEL
  43 #include <linux/sunrpc/bc_xprt.h>
  44 #endif
  45
  46 #include <net/sock.h>
  47 #include <net/checksum.h>
  48 #include <net/udp.h>
  49 #include <net/tcp.h>
  50 #include <linux/bvec.h>
  51 #include <linux/highmem.h>
  52 #include <linux/uio.h>
  53
  54 #include <trace/events/sunrpc.h>
  55
  56 #include "sunrpc.h"
  57
  58 static void xs_close(struct rpc_xprt *xprt);
  59 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  60                 struct socket *sock);
  61
  62 /*
  63  * xprtsock tunables
  64  */
  65 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  66 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  67 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  68
  69 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  70 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  71
  72 #define XS_TCP_LINGER_TO        (15U * HZ)
  73 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  74
  75 /*
  76  * We can register our own files under /proc/sys/sunrpc by
  77  * calling register_sysctl_table() again.  The files in that
  78  * directory become the union of all files registered there.
  79  *
  80  * We simply need to make sure that we don't collide with
  81  * someone else's file names!
  82  */
  83
  84 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  85 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  86 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  87 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  88 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  89
  90 static struct ctl_table_header *sunrpc_table_header;
  91
  92 /*
  93  * FIXME: changing the UDP slot table size should also resize the UDP
  94  *        socket buffers for existing UDP transports
  95  */
  96 static struct ctl_table xs_tunables_table[] = {
  97         {
  98                 .procname       = "udp_slot_table_entries",
  99                 .data           = &xprt_udp_slot_table_entries,
 100                 .maxlen         = sizeof(unsigned int),
 101                 .mode           = 0644,
 102                 .proc_handler   = proc_dointvec_minmax,
 103                 .extra1         = &min_slot_table_size,
 104                 .extra2         = &max_slot_table_size
 105         },
 106         {
 107                 .procname       = "tcp_slot_table_entries",
 108                 .data           = &xprt_tcp_slot_table_entries,
 109                 .maxlen         = sizeof(unsigned int),
 110                 .mode           = 0644,
 111                 .proc_handler   = proc_dointvec_minmax,
 112                 .extra1         = &min_slot_table_size,
 113                 .extra2         = &max_slot_table_size
 114         },
 115         {
 116                 .procname       = "tcp_max_slot_table_entries",
 117                 .data           = &xprt_max_tcp_slot_table_entries,
 118                 .maxlen         = sizeof(unsigned int),
 119                 .mode           = 0644,
 120                 .proc_handler   = proc_dointvec_minmax,
 121                 .extra1         = &min_slot_table_size,
 122                 .extra2         = &max_tcp_slot_table_limit
 123         },
 124         {
 125                 .procname       = "min_resvport",
 126                 .data           = &xprt_min_resvport,
 127                 .maxlen         = sizeof(unsigned int),
 128                 .mode           = 0644,
 129                 .proc_handler   = proc_dointvec_minmax,
 130                 .extra1         = &xprt_min_resvport_limit,
 131                 .extra2         = &xprt_max_resvport_limit
 132         },
 133         {
 134                 .procname       = "max_resvport",
 135                 .data           = &xprt_max_resvport,
 136                 .maxlen         = sizeof(unsigned int),
 137                 .mode           = 0644,
 138                 .proc_handler   = proc_dointvec_minmax,
 139                 .extra1         = &xprt_min_resvport_limit,
 140                 .extra2         = &xprt_max_resvport_limit
 141         },
 142         {
 143                 .procname       = "tcp_fin_timeout",
 144                 .data           = &xs_tcp_fin_timeout,
 145                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 146                 .mode           = 0644,
 147                 .proc_handler   = proc_dointvec_jiffies,
 148         },
 149         { },
 150 };
 151
 152 static struct ctl_table sunrpc_table[] = {
 153         {
 154                 .procname       = "sunrpc",
 155                 .mode           = 0555,
 156                 .child          = xs_tunables_table
 157         },
 158         { },
 159 };
 160
 161 /*
 162  * Wait duration for a reply from the RPC portmapper.
 163  */
 164 #define XS_BIND_TO              (60U * HZ)
 165
 166 /*
 167  * Delay if a UDP socket connect error occurs.  This is most likely some
 168  * kind of resource problem on the local host.
 169  */
 170 #define XS_UDP_REEST_TO         (2U * HZ)
 171
 172 /*
 173  * The reestablish timeout allows clients to delay for a bit before attempting
 174  * to reconnect to a server that just dropped our connection.
 175  *
 176  * We implement an exponential backoff when trying to reestablish a TCP
 177  * transport connection with the server.  Some servers like to drop a TCP
 178  * connection when they are overworked, so we start with a short timeout and
 179  * increase over time if the server is down or not responding.
 180  */
 181 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 182
 183 /*
 184  * TCP idle timeout; client drops the transport socket if it is idle
 185  * for this long.  Note that we also timeout UDP sockets to prevent
 186  * holding port numbers when there is no RPC traffic.
 187  */
 188 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 189
 190 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 191 # undef  RPC_DEBUG_DATA
 192 # define RPCDBG_FACILITY        RPCDBG_TRANS
 193 #endif
 194
 195 #ifdef RPC_DEBUG_DATA
 196 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 197 {
 198         u8 *buf = (u8 *) packet;
 199         int j;
 200
 201         dprintk("RPC:       %s\n", msg);
 202         for (j = 0; j < count && j < 128; j += 4) {
 203                 if (!(j & 31)) {
 204                         if (j)
 205                                 dprintk("\n");
 206                         dprintk("0x%04x ", j);
 207                 }
 208                 dprintk("%02x%02x%02x%02x ",
 209                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 210         }
 211         dprintk("\n");
 212 }
 213 #else
 214 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 215 {
 216         /* NOP */
 217 }
 218 #endif
 219
 220 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 221 {
 222         return (struct rpc_xprt *) sk->sk_user_data;
 223 }
 224
 225 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 226 {
 227         return (struct sockaddr *) &xprt->addr;
 228 }
 229
 230 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 231 {
 232         return (struct sockaddr_un *) &xprt->addr;
 233 }
 234
 235 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 236 {
 237         return (struct sockaddr_in *) &xprt->addr;
 238 }
 239
 240 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 241 {
 242         return (struct sockaddr_in6 *) &xprt->addr;
 243 }
 244
 245 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 246 {
 247         struct sockaddr *sap = xs_addr(xprt);
 248         struct sockaddr_in6 *sin6;
 249         struct sockaddr_in *sin;
 250         struct sockaddr_un *sun;
 251         char buf[128];
 252
 253         switch (sap->sa_family) {
 254         case AF_LOCAL:
 255                 sun = xs_addr_un(xprt);
 256                 strlcpy(buf, sun->sun_path, sizeof(buf));
 257                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 258                                                 kstrdup(buf, GFP_KERNEL);
 259                 break;
 260         case AF_INET:
 261                 (void)rpc_ntop(sap, buf, sizeof(buf));
 262                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 263                                                 kstrdup(buf, GFP_KERNEL);
 264                 sin = xs_addr_in(xprt);
 265                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 266                 break;
 267         case AF_INET6:
 268                 (void)rpc_ntop(sap, buf, sizeof(buf));
 269                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 270                                                 kstrdup(buf, GFP_KERNEL);
 271                 sin6 = xs_addr_in6(xprt);
 272                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 273                 break;
 274         default:
 275                 BUG();
 276         }
 277
 278         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 279 }
 280
 281 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 282 {
 283         struct sockaddr *sap = xs_addr(xprt);
 284         char buf[128];
 285
 286         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 287         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 288
 289         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 290         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 291 }
 292
 293 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 294                                      const char *protocol,
 295                                      const char *netid)
 296 {
 297         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 298         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 299         xs_format_common_peer_addresses(xprt);
 300         xs_format_common_peer_ports(xprt);
 301 }
 302
 303 static void xs_update_peer_port(struct rpc_xprt *xprt)
 304 {
 305         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 306         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 307
 308         xs_format_common_peer_ports(xprt);
 309 }
 310
 311 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 312 {
 313         unsigned int i;
 314
 315         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 316                 switch (i) {
 317                 case RPC_DISPLAY_PROTO:
 318                 case RPC_DISPLAY_NETID:
 319                         continue;
 320                 default:
 321                         kfree(xprt->address_strings[i]);
 322                 }
 323 }
 324
 325 static size_t
 326 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 327 {
 328         size_t i,n;
 329
 330         if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 331                 return want;
 332         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 333         for (i = 0; i < n; i++) {
 334                 if (buf->pages[i])
 335                         continue;
 336                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 337                 if (!buf->pages[i]) {
 338                         i *= PAGE_SIZE;
 339                         return i > buf->page_base ? i - buf->page_base : 0;
 340                 }
 341         }
 342         return want;
 343 }
 344
 345 static ssize_t
 346 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 347 {
 348         ssize_t ret;
 349         if (seek != 0)
 350                 iov_iter_advance(&msg->msg_iter, seek);
 351         ret = sock_recvmsg(sock, msg, flags);
 352         return ret > 0 ? ret + seek : ret;
 353 }
 354
 355 static ssize_t
 356 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 357                 struct kvec *kvec, size_t count, size_t seek)
 358 {
 359         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 360         return xs_sock_recvmsg(sock, msg, flags, seek);
 361 }
 362
 363 static ssize_t
 364 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 365                 struct bio_vec *bvec, unsigned long nr, size_t count,
 366                 size_t seek)
 367 {
 368         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 369         return xs_sock_recvmsg(sock, msg, flags, seek);
 370 }
 371
 372 static ssize_t
 373 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 374                 size_t count)
 375 {
 376         iov_iter_discard(&msg->msg_iter, READ, count);
 377         return sock_recvmsg(sock, msg, flags);
 378 }
 379
 380 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 381 static void
 382 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 383 {
 384         struct bvec_iter bi = {
 385                 .bi_size = count,
 386         };
 387         struct bio_vec bv;
 388
 389         bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 390         for_each_bvec(bv, bvec, bi, bi)
 391                 flush_dcache_page(bv.bv_page);
 392 }
 393 #else
 394 static inline void
 395 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 396 {
 397 }
 398 #endif
 399
 400 static ssize_t
 401 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 402                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 403 {
 404         size_t want, seek_init = seek, offset = 0;
 405         ssize_t ret;
 406
 407         if (seek < buf->head[0].iov_len) {
 408                 want = min_t(size_t, count, buf->head[0].iov_len);
 409                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 410                 if (ret <= 0)
 411                         goto sock_err;
 412                 offset += ret;
 413                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 414                         goto out;
 415                 if (ret != want)
 416                         goto out;
 417                 seek = 0;
 418         } else {
 419                 seek -= buf->head[0].iov_len;
 420                 offset += buf->head[0].iov_len;
 421         }
 422
 423         want = xs_alloc_sparse_pages(buf,
 424                         min_t(size_t, count - offset, buf->page_len),
 425                         GFP_NOWAIT);
 426         if (seek < want) {
 427                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 428                                 xdr_buf_pagecount(buf),
 429                                 want + buf->page_base,
 430                                 seek + buf->page_base);
 431                 if (ret <= 0)
 432                         goto sock_err;
 433                 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 434                 offset += ret - buf->page_base;
 435                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 436                         goto out;
 437                 if (ret != want)
 438                         goto out;
 439                 seek = 0;
 440         } else {
 441                 seek -= want;
 442                 offset += want;
 443         }
 444
 445         if (seek < buf->tail[0].iov_len) {
 446                 want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 447                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 448                 if (ret <= 0)
 449                         goto sock_err;
 450                 offset += ret;
 451                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 452                         goto out;
 453                 if (ret != want)
 454                         goto out;
 455         } else
 456                 offset += buf->tail[0].iov_len;
 457         ret = -EMSGSIZE;
 458 out:
 459         *read = offset - seek_init;
 460         return ret;
 461 sock_err:
 462         offset += seek;
 463         goto out;
 464 }
 465
 466 static void
 467 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 468 {
 469         if (!transport->recv.copied) {
 470                 if (buf->head[0].iov_len >= transport->recv.offset)
 471                         memcpy(buf->head[0].iov_base,
 472                                         &transport->recv.xid,
 473                                         transport->recv.offset);
 474                 transport->recv.copied = transport->recv.offset;
 475         }
 476 }
 477
 478 static bool
 479 xs_read_stream_request_done(struct sock_xprt *transport)
 480 {
 481         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 482 }
 483
 484 static ssize_t
 485 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 486                 int flags, struct rpc_rqst *req)
 487 {
 488         struct xdr_buf *buf = &req->rq_private_buf;
 489         size_t want, read;
 490         ssize_t ret;
 491
 492         xs_read_header(transport, buf);
 493
 494         want = transport->recv.len - transport->recv.offset;
 495         ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 496                         transport->recv.copied + want, transport->recv.copied,
 497                         &read);
 498         transport->recv.offset += read;
 499         transport->recv.copied += read;
 500         if (transport->recv.offset == transport->recv.len) {
 501                 if (xs_read_stream_request_done(transport))
 502                         msg->msg_flags |= MSG_EOR;
 503                 return read;
 504         }
 505
 506         switch (ret) {
 507         default:
 508                 break;
 509         case -EFAULT:
 510         case -EMSGSIZE:
 511                 msg->msg_flags |= MSG_TRUNC;
 512                 return read;
 513         case 0:
 514                 return -ESHUTDOWN;
 515         }
 516         return ret < 0 ? ret : read;
 517 }
 518
 519 static size_t
 520 xs_read_stream_headersize(bool isfrag)
 521 {
 522         if (isfrag)
 523                 return sizeof(__be32);
 524         return 3 * sizeof(__be32);
 525 }
 526
 527 static ssize_t
 528 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 529                 int flags, size_t want, size_t seek)
 530 {
 531         struct kvec kvec = {
 532                 .iov_base = &transport->recv.fraghdr,
 533                 .iov_len = want,
 534         };
 535         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 536 }
 537
 538 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 539 static ssize_t
 540 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 541 {
 542         struct rpc_xprt *xprt = &transport->xprt;
 543         struct rpc_rqst *req;
 544         ssize_t ret;
 545
 546         /* Look up and lock the request corresponding to the given XID */
 547         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 548         if (!req) {
 549                 printk(KERN_WARNING "Callback slot table overflowed\n");
 550                 return -ESHUTDOWN;
 551         }
 552
 553         ret = xs_read_stream_request(transport, msg, flags, req);
 554         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 555                 xprt_complete_bc_request(req, transport->recv.copied);
 556
 557         return ret;
 558 }
 559 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 560 static ssize_t
 561 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 562 {
 563         return -ESHUTDOWN;
 564 }
 565 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 566
 567 static ssize_t
 568 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 569 {
 570         struct rpc_xprt *xprt = &transport->xprt;
 571         struct rpc_rqst *req;
 572         ssize_t ret = 0;
 573
 574         /* Look up and lock the request corresponding to the given XID */
 575         spin_lock(&xprt->queue_lock);
 576         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 577         if (!req) {
 578                 msg->msg_flags |= MSG_TRUNC;
 579                 goto out;
 580         }
 581         xprt_pin_rqst(req);
 582         spin_unlock(&xprt->queue_lock);
 583
 584         ret = xs_read_stream_request(transport, msg, flags, req);
 585
 586         spin_lock(&xprt->queue_lock);
 587         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 588                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 589         xprt_unpin_rqst(req);
 590 out:
 591         spin_unlock(&xprt->queue_lock);
 592         return ret;
 593 }
 594
 595 static ssize_t
 596 xs_read_stream(struct sock_xprt *transport, int flags)
 597 {
 598         struct msghdr msg = { 0 };
 599         size_t want, read = 0;
 600         ssize_t ret = 0;
 601
 602         if (transport->recv.len == 0) {
 603                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 604                 ret = xs_read_stream_header(transport, &msg, flags, want,
 605                                 transport->recv.offset);
 606                 if (ret <= 0)
 607                         goto out_err;
 608                 transport->recv.offset = ret;
 609                 if (transport->recv.offset != want)
 610                         return transport->recv.offset;
 611                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 612                         RPC_FRAGMENT_SIZE_MASK;
 613                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 614                 read = ret;
 615         }
 616
 617         switch (be32_to_cpu(transport->recv.calldir)) {
 618         default:
 619                 msg.msg_flags |= MSG_TRUNC;
 620                 break;
 621         case RPC_CALL:
 622                 ret = xs_read_stream_call(transport, &msg, flags);
 623                 break;
 624         case RPC_REPLY:
 625                 ret = xs_read_stream_reply(transport, &msg, flags);
 626         }
 627         if (msg.msg_flags & MSG_TRUNC) {
 628                 transport->recv.calldir = cpu_to_be32(-1);
 629                 transport->recv.copied = -1;
 630         }
 631         if (ret < 0)
 632                 goto out_err;
 633         read += ret;
 634         if (transport->recv.offset < transport->recv.len) {
 635                 if (!(msg.msg_flags & MSG_TRUNC))
 636                         return read;
 637                 msg.msg_flags = 0;
 638                 ret = xs_read_discard(transport->sock, &msg, flags,
 639                                 transport->recv.len - transport->recv.offset);
 640                 if (ret <= 0)
 641                         goto out_err;
 642                 transport->recv.offset += ret;
 643                 read += ret;
 644                 if (transport->recv.offset != transport->recv.len)
 645                         return read;
 646         }
 647         if (xs_read_stream_request_done(transport)) {
 648                 trace_xs_stream_read_request(transport);
 649                 transport->recv.copied = 0;
 650         }
 651         transport->recv.offset = 0;
 652         transport->recv.len = 0;
 653         return read;
 654 out_err:
 655         return ret != 0 ? ret : -ESHUTDOWN;
 656 }
 657
 658 static void xs_stream_data_receive(struct sock_xprt *transport)
 659 {
 660         size_t read = 0;
 661         ssize_t ret = 0;
 662
 663         mutex_lock(&transport->recv_mutex);
 664         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 665         if (transport->sock == NULL)
 666                 goto out;
 667         for (;;) {
 668                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 669                 if (ret < 0)
 670                         break;
 671                 read += ret;
 672                 cond_resched();
 673         }
 674 out:
 675         mutex_unlock(&transport->recv_mutex);
 676         trace_xs_stream_read_data(&transport->xprt, ret, read);
 677 }
 678
 679 static void xs_stream_data_receive_workfn(struct work_struct *work)
 680 {
 681         struct sock_xprt *transport =
 682                 container_of(work, struct sock_xprt, recv_worker);
 683         xs_stream_data_receive(transport);
 684 }
 685
 686 static void
 687 xs_stream_reset_connect(struct sock_xprt *transport)
 688 {
 689         transport->recv.offset = 0;
 690         transport->recv.len = 0;
 691         transport->recv.copied = 0;
 692         transport->xmit.offset = 0;
 693         transport->xprt.stat.connect_count++;
 694         transport->xprt.stat.connect_start = jiffies;
 695 }
 696
 697 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 698
 699 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 700 {
 701         struct msghdr msg = {
 702                 .msg_name       = addr,
 703                 .msg_namelen    = addrlen,
 704                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 705         };
 706         struct kvec iov = {
 707                 .iov_base       = vec->iov_base + base,
 708                 .iov_len        = vec->iov_len - base,
 709         };
 710
 711         if (iov.iov_len != 0)
 712                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 713         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 714 }
 715
 716 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p)
 717 {
 718         ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 719                         int offset, size_t size, int flags);
 720         struct page **ppage;
 721         unsigned int remainder;
 722         int err;
 723
 724         remainder = xdr->page_len - base;
 725         base += xdr->page_base;
 726         ppage = xdr->pages + (base >> PAGE_SHIFT);
 727         base &= ~PAGE_MASK;
 728         do_sendpage = sock->ops->sendpage;
 729         if (!zerocopy)
 730                 do_sendpage = sock_no_sendpage;
 731         for(;;) {
 732                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 733                 int flags = XS_SENDMSG_FLAGS;
 734
 735                 remainder -= len;
 736                 if (more)
 737                         flags |= MSG_MORE;
 738                 if (remainder != 0)
 739                         flags |= MSG_SENDPAGE_NOTLAST | MSG_MORE;
 740                 err = do_sendpage(sock, *ppage, base, len, flags);
 741                 if (remainder == 0 || err != len)
 742                         break;
 743                 *sent_p += err;
 744                 ppage++;
 745                 base = 0;
 746         }
 747         if (err > 0) {
 748                 *sent_p += err;
 749                 err = 0;
 750         }
 751         return err;
 752 }
 753
 754 /**
 755  * xs_sendpages - write pages directly to a socket
 756  * @sock: socket to send on
 757  * @addr: UDP only -- address of destination
 758  * @addrlen: UDP only -- length of destination address
 759  * @xdr: buffer containing this request
 760  * @base: starting position in the buffer
 761  * @zerocopy: true if it is safe to use sendpage()
 762  * @sent_p: return the total number of bytes successfully queued for sending
 763  *
 764  */
 765 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 766 {
 767         unsigned int remainder = xdr->len - base;
 768         int err = 0;
 769         int sent = 0;
 770
 771         if (unlikely(!sock))
 772                 return -ENOTSOCK;
 773
 774         if (base != 0) {
 775                 addr = NULL;
 776                 addrlen = 0;
 777         }
 778
 779         if (base < xdr->head[0].iov_len || addr != NULL) {
 780                 unsigned int len = xdr->head[0].iov_len - base;
 781                 remainder -= len;
 782                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 783                 if (remainder == 0 || err != len)
 784                         goto out;
 785                 *sent_p += err;
 786                 base = 0;
 787         } else
 788                 base -= xdr->head[0].iov_len;
 789
 790         if (base < xdr->page_len) {
 791                 unsigned int len = xdr->page_len - base;
 792                 remainder -= len;
 793                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 794                 *sent_p += sent;
 795                 if (remainder == 0 || sent != len)
 796                         goto out;
 797                 base = 0;
 798         } else
 799                 base -= xdr->page_len;
 800
 801         if (base >= xdr->tail[0].iov_len)
 802                 return 0;
 803         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 804 out:
 805         if (err > 0) {
 806                 *sent_p += err;
 807                 err = 0;
 808         }
 809         return err;
 810 }
 811
 812 /**
 813  * xs_nospace - handle transmit was incomplete
 814  * @req: pointer to RPC request
 815  *
 816  */
 817 static int xs_nospace(struct rpc_rqst *req)
 818 {
 819         struct rpc_xprt *xprt = req->rq_xprt;
 820         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 821         struct sock *sk = transport->inet;
 822         int ret = -EAGAIN;
 823
 824         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 825                         req->rq_task->tk_pid,
 826                         req->rq_slen - transport->xmit.offset,
 827                         req->rq_slen);
 828
 829         /* Protect against races with write_space */
 830         spin_lock_bh(&xprt->transport_lock);
 831
 832         /* Don't race with disconnect */
 833         if (xprt_connected(xprt)) {
 834                 /* wait for more buffer space */
 835                 sk->sk_write_pending++;
 836                 xprt_wait_for_buffer_space(xprt);
 837         } else
 838                 ret = -ENOTCONN;
 839
 840         spin_unlock_bh(&xprt->transport_lock);
 841
 842         /* Race breaker in case memory is freed before above code is called */
 843         if (ret == -EAGAIN) {
 844                 struct socket_wq *wq;
 845
 846                 rcu_read_lock();
 847                 wq = rcu_dereference(sk->sk_wq);
 848                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 849                 rcu_read_unlock();
 850
 851                 sk->sk_write_space(sk);
 852         }
 853         return ret;
 854 }
 855
 856 static void
 857 xs_stream_prepare_request(struct rpc_rqst *req)
 858 {
 859         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_NOIO);
 860 }
 861
 862 /*
 863  * Determine if the previous message in the stream was aborted before it
 864  * could complete transmission.
 865  */
 866 static bool
 867 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 868 {
 869         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 870 }
 871
 872 /*
 873  * Construct a stream transport record marker in @buf.
 874  */
 875 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 876 {
 877         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 878         rpc_fraghdr *base = buf->head[0].iov_base;
 879         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 880 }
 881
 882 /**
 883  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 884  * @req: pointer to RPC request
 885  *
 886  * Return values:
 887  *        0:    The request has been sent
 888  *   EAGAIN:    The socket was blocked, please call again later to
 889  *              complete the request
 890  * ENOTCONN:    Caller needs to invoke connect logic then call again
 891  *    other:    Some other error occured, the request was not sent
 892  */
 893 static int xs_local_send_request(struct rpc_rqst *req)
 894 {
 895         struct rpc_xprt *xprt = req->rq_xprt;
 896         struct sock_xprt *transport =
 897                                 container_of(xprt, struct sock_xprt, xprt);
 898         struct xdr_buf *xdr = &req->rq_snd_buf;
 899         int status;
 900         int sent = 0;
 901
 902         /* Close the stream if the previous transmission was incomplete */
 903         if (xs_send_request_was_aborted(transport, req)) {
 904                 xs_close(xprt);
 905                 return -ENOTCONN;
 906         }
 907
 908         xs_encode_stream_record_marker(&req->rq_snd_buf);
 909
 910         xs_pktdump("packet data:",
 911                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 912
 913         req->rq_xtime = ktime_get();
 914         status = xs_sendpages(transport->sock, NULL, 0, xdr,
 915                               transport->xmit.offset,
 916                               true, &sent);
 917         dprintk("RPC:       %s(%u) = %d\n",
 918                         __func__, xdr->len - transport->xmit.offset, status);
 919
 920         if (status == -EAGAIN && sock_writeable(transport->inet))
 921                 status = -ENOBUFS;
 922
 923         if (likely(sent > 0) || status == 0) {
 924                 transport->xmit.offset += sent;
 925                 req->rq_bytes_sent = transport->xmit.offset;
 926                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 927                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 928                         req->rq_bytes_sent = 0;
 929                         transport->xmit.offset = 0;
 930                         return 0;
 931                 }
 932                 status = -EAGAIN;
 933         }
 934
 935         switch (status) {
 936         case -ENOBUFS:
 937                 break;
 938         case -EAGAIN:
 939                 status = xs_nospace(req);
 940                 break;
 941         default:
 942                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 943                         -status);
 944                 /* fall through */
 945         case -EPIPE:
 946                 xs_close(xprt);
 947                 status = -ENOTCONN;
 948         }
 949
 950         return status;
 951 }
 952
 953 /**
 954  * xs_udp_send_request - write an RPC request to a UDP socket
 955  * @req: pointer to RPC request
 956  *
 957  * Return values:
 958  *        0:    The request has been sent
 959  *   EAGAIN:    The socket was blocked, please call again later to
 960  *              complete the request
 961  * ENOTCONN:    Caller needs to invoke connect logic then call again
 962  *    other:    Some other error occurred, the request was not sent
 963  */
 964 static int xs_udp_send_request(struct rpc_rqst *req)
 965 {
 966         struct rpc_xprt *xprt = req->rq_xprt;
 967         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 968         struct xdr_buf *xdr = &req->rq_snd_buf;
 969         int sent = 0;
 970         int status;
 971
 972         xs_pktdump("packet data:",
 973                                 req->rq_svec->iov_base,
 974                                 req->rq_svec->iov_len);
 975
 976         if (!xprt_bound(xprt))
 977                 return -ENOTCONN;
 978
 979         if (!xprt_request_get_cong(xprt, req))
 980                 return -EBADSLT;
 981
 982         req->rq_xtime = ktime_get();
 983         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 984                               xdr, 0, true, &sent);
 985
 986         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 987                         xdr->len, status);
 988
 989         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 990         if (status == -EPERM)
 991                 goto process_status;
 992
 993         if (status == -EAGAIN && sock_writeable(transport->inet))
 994                 status = -ENOBUFS;
 995
 996         if (sent > 0 || status == 0) {
 997                 req->rq_xmit_bytes_sent += sent;
 998                 if (sent >= req->rq_slen)
 999                         return 0;
1000                 /* Still some bytes left; set up for a retry later. */
1001                 status = -EAGAIN;
1002         }
1003
1004 process_status:
1005         switch (status) {
1006         case -ENOTSOCK:
1007                 status = -ENOTCONN;
1008                 /* Should we call xs_close() here? */
1009                 break;
1010         case -EAGAIN:
1011                 status = xs_nospace(req);
1012                 break;
1013         case -ENETUNREACH:
1014         case -ENOBUFS:
1015         case -EPIPE:
1016         case -ECONNREFUSED:
1017         case -EPERM:
1018                 /* When the server has died, an ICMP port unreachable message
1019                  * prompts ECONNREFUSED. */
1020                 break;
1021         default:
1022                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1023                         -status);
1024         }
1025
1026         return status;
1027 }
1028
1029 /**
1030  * xs_tcp_send_request - write an RPC request to a TCP socket
1031  * @req: pointer to RPC request
1032  *
1033  * Return values:
1034  *        0:    The request has been sent
1035  *   EAGAIN:    The socket was blocked, please call again later to
1036  *              complete the request
1037  * ENOTCONN:    Caller needs to invoke connect logic then call again
1038  *    other:    Some other error occurred, the request was not sent
1039  *
1040  * XXX: In the case of soft timeouts, should we eventually give up
1041  *      if sendmsg is not able to make progress?
1042  */
1043 static int xs_tcp_send_request(struct rpc_rqst *req)
1044 {
1045         struct rpc_xprt *xprt = req->rq_xprt;
1046         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1047         struct xdr_buf *xdr = &req->rq_snd_buf;
1048         bool zerocopy = true;
1049         bool vm_wait = false;
1050         int status;
1051         int sent;
1052
1053         /* Close the stream if the previous transmission was incomplete */
1054         if (xs_send_request_was_aborted(transport, req)) {
1055                 if (transport->sock != NULL)
1056                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1057                 return -ENOTCONN;
1058         }
1059
1060         xs_encode_stream_record_marker(&req->rq_snd_buf);
1061
1062         xs_pktdump("packet data:",
1063                                 req->rq_svec->iov_base,
1064                                 req->rq_svec->iov_len);
1065         /* Don't use zero copy if this is a resend. If the RPC call
1066          * completes while the socket holds a reference to the pages,
1067          * then we may end up resending corrupted data.
1068          */
1069         if (req->rq_task->tk_flags & RPC_TASK_SENT)
1070                 zerocopy = false;
1071
1072         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1073                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1074
1075         /* Continue transmitting the packet/record. We must be careful
1076          * to cope with writespace callbacks arriving _after_ we have
1077          * called sendmsg(). */
1078         req->rq_xtime = ktime_get();
1079         while (1) {
1080                 sent = 0;
1081                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1082                                       transport->xmit.offset,
1083                                       zerocopy, &sent);
1084
1085                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1086                                 xdr->len - transport->xmit.offset, status);
1087
1088                 /* If we've sent the entire packet, immediately
1089                  * reset the count of bytes sent. */
1090                 transport->xmit.offset += sent;
1091                 req->rq_bytes_sent = transport->xmit.offset;
1092                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
1093                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1094                         req->rq_bytes_sent = 0;
1095                         transport->xmit.offset = 0;
1096                         return 0;
1097                 }
1098
1099                 WARN_ON_ONCE(sent == 0 && status == 0);
1100
1101                 if (status == -EAGAIN ) {
1102                         /*
1103                          * Return EAGAIN if we're sure we're hitting the
1104                          * socket send buffer limits.
1105                          */
1106                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1107                                 break;
1108                         /*
1109                          * Did we hit a memory allocation failure?
1110                          */
1111                         if (sent == 0) {
1112                                 status = -ENOBUFS;
1113                                 if (vm_wait)
1114                                         break;
1115                                 /* Retry, knowing now that we're below the
1116                                  * socket send buffer limit
1117                                  */
1118                                 vm_wait = true;
1119                         }
1120                         continue;
1121                 }
1122                 if (status < 0)
1123                         break;
1124                 vm_wait = false;
1125         }
1126
1127         switch (status) {
1128         case -ENOTSOCK:
1129                 status = -ENOTCONN;
1130                 /* Should we call xs_close() here? */
1131                 break;
1132         case -EAGAIN:
1133                 status = xs_nospace(req);
1134                 break;
1135         case -ECONNRESET:
1136         case -ECONNREFUSED:
1137         case -ENOTCONN:
1138         case -EADDRINUSE:
1139         case -ENOBUFS:
1140         case -EPIPE:
1141                 break;
1142         default:
1143                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1144                         -status);
1145         }
1146
1147         return status;
1148 }
1149
1150 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1151 {
1152         transport->old_data_ready = sk->sk_data_ready;
1153         transport->old_state_change = sk->sk_state_change;
1154         transport->old_write_space = sk->sk_write_space;
1155         transport->old_error_report = sk->sk_error_report;
1156 }
1157
1158 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1159 {
1160         sk->sk_data_ready = transport->old_data_ready;
1161         sk->sk_state_change = transport->old_state_change;
1162         sk->sk_write_space = transport->old_write_space;
1163         sk->sk_error_report = transport->old_error_report;
1164 }
1165
1166 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1167 {
1168         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1169
1170         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1171 }
1172
1173 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1174 {
1175         smp_mb__before_atomic();
1176         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1177         clear_bit(XPRT_CLOSING, &xprt->state);
1178         xs_sock_reset_state_flags(xprt);
1179         smp_mb__after_atomic();
1180 }
1181
1182 /**
1183  * xs_error_report - callback to handle TCP socket state errors
1184  * @sk: socket
1185  *
1186  * Note: we don't call sock_error() since there may be a rpc_task
1187  * using the socket, and so we don't want to clear sk->sk_err.
1188  */
1189 static void xs_error_report(struct sock *sk)
1190 {
1191         struct rpc_xprt *xprt;
1192         int err;
1193
1194         read_lock_bh(&sk->sk_callback_lock);
1195         if (!(xprt = xprt_from_sock(sk)))
1196                 goto out;
1197
1198         err = -sk->sk_err;
1199         if (err == 0)
1200                 goto out;
1201         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1202                         xprt, -err);
1203         trace_rpc_socket_error(xprt, sk->sk_socket, err);
1204         xprt_wake_pending_tasks(xprt, err);
1205  out:
1206         read_unlock_bh(&sk->sk_callback_lock);
1207 }
1208
1209 static void xs_reset_transport(struct sock_xprt *transport)
1210 {
1211         struct socket *sock = transport->sock;
1212         struct sock *sk = transport->inet;
1213         struct rpc_xprt *xprt = &transport->xprt;
1214
1215         if (sk == NULL)
1216                 return;
1217
1218         if (atomic_read(&transport->xprt.swapper))
1219                 sk_clear_memalloc(sk);
1220
1221         kernel_sock_shutdown(sock, SHUT_RDWR);
1222
1223         mutex_lock(&transport->recv_mutex);
1224         write_lock_bh(&sk->sk_callback_lock);
1225         transport->inet = NULL;
1226         transport->sock = NULL;
1227
1228         sk->sk_user_data = NULL;
1229
1230         xs_restore_old_callbacks(transport, sk);
1231         xprt_clear_connected(xprt);
1232         write_unlock_bh(&sk->sk_callback_lock);
1233         xs_sock_reset_connection_flags(xprt);
1234         mutex_unlock(&transport->recv_mutex);
1235
1236         trace_rpc_socket_close(xprt, sock);
1237         sock_release(sock);
1238
1239         xprt_disconnect_done(xprt);
1240 }
1241
1242 /**
1243  * xs_close - close a socket
1244  * @xprt: transport
1245  *
1246  * This is used when all requests are complete; ie, no DRC state remains
1247  * on the server we want to save.
1248  *
1249  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1250  * xs_reset_transport() zeroing the socket from underneath a writer.
1251  */
1252 static void xs_close(struct rpc_xprt *xprt)
1253 {
1254         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1255
1256         dprintk("RPC:       xs_close xprt %p\n", xprt);
1257
1258         xs_reset_transport(transport);
1259         xprt->reestablish_timeout = 0;
1260 }
1261
1262 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1263 {
1264         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1265                 xprt);
1266         xprt_disconnect_done(xprt);
1267 }
1268
1269 static void xs_xprt_free(struct rpc_xprt *xprt)
1270 {
1271         xs_free_peer_addresses(xprt);
1272         xprt_free(xprt);
1273 }
1274
1275 /**
1276  * xs_destroy - prepare to shutdown a transport
1277  * @xprt: doomed transport
1278  *
1279  */
1280 static void xs_destroy(struct rpc_xprt *xprt)
1281 {
1282         struct sock_xprt *transport = container_of(xprt,
1283                         struct sock_xprt, xprt);
1284         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1285
1286         cancel_delayed_work_sync(&transport->connect_worker);
1287         xs_close(xprt);
1288         cancel_work_sync(&transport->recv_worker);
1289         xs_xprt_free(xprt);
1290         module_put(THIS_MODULE);
1291 }
1292
1293 /**
1294  * xs_udp_data_read_skb - receive callback for UDP sockets
1295  * @xprt: transport
1296  * @sk: socket
1297  * @skb: skbuff
1298  *
1299  */
1300 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1301                 struct sock *sk,
1302                 struct sk_buff *skb)
1303 {
1304         struct rpc_task *task;
1305         struct rpc_rqst *rovr;
1306         int repsize, copied;
1307         u32 _xid;
1308         __be32 *xp;
1309
1310         repsize = skb->len;
1311         if (repsize < 4) {
1312                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1313                 return;
1314         }
1315
1316         /* Copy the XID from the skb... */
1317         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1318         if (xp == NULL)
1319                 return;
1320
1321         /* Look up and lock the request corresponding to the given XID */
1322         spin_lock(&xprt->queue_lock);
1323         rovr = xprt_lookup_rqst(xprt, *xp);
1324         if (!rovr)
1325                 goto out_unlock;
1326         xprt_pin_rqst(rovr);
1327         xprt_update_rtt(rovr->rq_task);
1328         spin_unlock(&xprt->queue_lock);
1329         task = rovr->rq_task;
1330
1331         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1332                 copied = repsize;
1333
1334         /* Suck it into the iovec, verify checksum if not done by hw. */
1335         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1336                 spin_lock(&xprt->queue_lock);
1337                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1338                 goto out_unpin;
1339         }
1340
1341
1342         spin_lock_bh(&xprt->transport_lock);
1343         xprt_adjust_cwnd(xprt, task, copied);
1344         spin_unlock_bh(&xprt->transport_lock);
1345         spin_lock(&xprt->queue_lock);
1346         xprt_complete_rqst(task, copied);
1347         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1348 out_unpin:
1349         xprt_unpin_rqst(rovr);
1350  out_unlock:
1351         spin_unlock(&xprt->queue_lock);
1352 }
1353
1354 static void xs_udp_data_receive(struct sock_xprt *transport)
1355 {
1356         struct sk_buff *skb;
1357         struct sock *sk;
1358         int err;
1359
1360         mutex_lock(&transport->recv_mutex);
1361         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1362         sk = transport->inet;
1363         if (sk == NULL)
1364                 goto out;
1365         for (;;) {
1366                 skb = skb_recv_udp(sk, 0, 1, &err);
1367                 if (skb == NULL)
1368                         break;
1369                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1370                 consume_skb(skb);
1371                 cond_resched();
1372         }
1373 out:
1374         mutex_unlock(&transport->recv_mutex);
1375 }
1376
1377 static void xs_udp_data_receive_workfn(struct work_struct *work)
1378 {
1379         struct sock_xprt *transport =
1380                 container_of(work, struct sock_xprt, recv_worker);
1381         xs_udp_data_receive(transport);
1382 }
1383
1384 /**
1385  * xs_data_ready - "data ready" callback for UDP sockets
1386  * @sk: socket with data to read
1387  *
1388  */
1389 static void xs_data_ready(struct sock *sk)
1390 {
1391         struct rpc_xprt *xprt;
1392
1393         read_lock_bh(&sk->sk_callback_lock);
1394         dprintk("RPC:       xs_data_ready...\n");
1395         xprt = xprt_from_sock(sk);
1396         if (xprt != NULL) {
1397                 struct sock_xprt *transport = container_of(xprt,
1398                                 struct sock_xprt, xprt);
1399                 transport->old_data_ready(sk);
1400                 /* Any data means we had a useful conversation, so
1401                  * then we don't need to delay the next reconnect
1402                  */
1403                 if (xprt->reestablish_timeout)
1404                         xprt->reestablish_timeout = 0;
1405                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1406                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1407         }
1408         read_unlock_bh(&sk->sk_callback_lock);
1409 }
1410
1411 /*
1412  * Helper function to force a TCP close if the server is sending
1413  * junk and/or it has put us in CLOSE_WAIT
1414  */
1415 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1416 {
1417         xprt_force_disconnect(xprt);
1418 }
1419
1420 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1421 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1422 {
1423         return PAGE_SIZE;
1424 }
1425 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1426
1427 /**
1428  * xs_tcp_state_change - callback to handle TCP socket state changes
1429  * @sk: socket whose state has changed
1430  *
1431  */
1432 static void xs_tcp_state_change(struct sock *sk)
1433 {
1434         struct rpc_xprt *xprt;
1435         struct sock_xprt *transport;
1436
1437         read_lock_bh(&sk->sk_callback_lock);
1438         if (!(xprt = xprt_from_sock(sk)))
1439                 goto out;
1440         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1441         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1442                         sk->sk_state, xprt_connected(xprt),
1443                         sock_flag(sk, SOCK_DEAD),
1444                         sock_flag(sk, SOCK_ZAPPED),
1445                         sk->sk_shutdown);
1446
1447         transport = container_of(xprt, struct sock_xprt, xprt);
1448         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1449         switch (sk->sk_state) {
1450         case TCP_ESTABLISHED:
1451                 spin_lock(&xprt->transport_lock);
1452                 if (!xprt_test_and_set_connected(xprt)) {
1453                         xprt->connect_cookie++;
1454                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1455                         xprt_clear_connecting(xprt);
1456
1457                         xprt->stat.connect_count++;
1458                         xprt->stat.connect_time += (long)jiffies -
1459                                                    xprt->stat.connect_start;
1460                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1461                 }
1462                 spin_unlock(&xprt->transport_lock);
1463                 break;
1464         case TCP_FIN_WAIT1:
1465                 /* The client initiated a shutdown of the socket */
1466                 xprt->connect_cookie++;
1467                 xprt->reestablish_timeout = 0;
1468                 set_bit(XPRT_CLOSING, &xprt->state);
1469                 smp_mb__before_atomic();
1470                 clear_bit(XPRT_CONNECTED, &xprt->state);
1471                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1472                 smp_mb__after_atomic();
1473                 break;
1474         case TCP_CLOSE_WAIT:
1475                 /* The server initiated a shutdown of the socket */
1476                 xprt->connect_cookie++;
1477                 clear_bit(XPRT_CONNECTED, &xprt->state);
1478                 xs_tcp_force_close(xprt);
1479                 /* fall through */
1480         case TCP_CLOSING:
1481                 /*
1482                  * If the server closed down the connection, make sure that
1483                  * we back off before reconnecting
1484                  */
1485                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1486                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1487                 break;
1488         case TCP_LAST_ACK:
1489                 set_bit(XPRT_CLOSING, &xprt->state);
1490                 smp_mb__before_atomic();
1491                 clear_bit(XPRT_CONNECTED, &xprt->state);
1492                 smp_mb__after_atomic();
1493                 break;
1494         case TCP_CLOSE:
1495                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1496                                         &transport->sock_state))
1497                         xprt_clear_connecting(xprt);
1498                 clear_bit(XPRT_CLOSING, &xprt->state);
1499                 /* Trigger the socket release */
1500                 xs_tcp_force_close(xprt);
1501         }
1502  out:
1503         read_unlock_bh(&sk->sk_callback_lock);
1504 }
1505
1506 static void xs_write_space(struct sock *sk)
1507 {
1508         struct socket_wq *wq;
1509         struct rpc_xprt *xprt;
1510
1511         if (!sk->sk_socket)
1512                 return;
1513         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1514
1515         if (unlikely(!(xprt = xprt_from_sock(sk))))
1516                 return;
1517         rcu_read_lock();
1518         wq = rcu_dereference(sk->sk_wq);
1519         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1520                 goto out;
1521
1522         if (xprt_write_space(xprt))
1523                 sk->sk_write_pending--;
1524 out:
1525         rcu_read_unlock();
1526 }
1527
1528 /**
1529  * xs_udp_write_space - callback invoked when socket buffer space
1530  *                             becomes available
1531  * @sk: socket whose state has changed
1532  *
1533  * Called when more output buffer space is available for this socket.
1534  * We try not to wake our writers until they can make "significant"
1535  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1536  * with a bunch of small requests.
1537  */
1538 static void xs_udp_write_space(struct sock *sk)
1539 {
1540         read_lock_bh(&sk->sk_callback_lock);
1541
1542         /* from net/core/sock.c:sock_def_write_space */
1543         if (sock_writeable(sk))
1544                 xs_write_space(sk);
1545
1546         read_unlock_bh(&sk->sk_callback_lock);
1547 }
1548
1549 /**
1550  * xs_tcp_write_space - callback invoked when socket buffer space
1551  *                             becomes available
1552  * @sk: socket whose state has changed
1553  *
1554  * Called when more output buffer space is available for this socket.
1555  * We try not to wake our writers until they can make "significant"
1556  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1557  * with a bunch of small requests.
1558  */
1559 static void xs_tcp_write_space(struct sock *sk)
1560 {
1561         read_lock_bh(&sk->sk_callback_lock);
1562
1563         /* from net/core/stream.c:sk_stream_write_space */
1564         if (sk_stream_is_writeable(sk))
1565                 xs_write_space(sk);
1566
1567         read_unlock_bh(&sk->sk_callback_lock);
1568 }
1569
1570 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1571 {
1572         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1573         struct sock *sk = transport->inet;
1574
1575         if (transport->rcvsize) {
1576                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1577                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1578         }
1579         if (transport->sndsize) {
1580                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1581                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1582                 sk->sk_write_space(sk);
1583         }
1584 }
1585
1586 /**
1587  * xs_udp_set_buffer_size - set send and receive limits
1588  * @xprt: generic transport
1589  * @sndsize: requested size of send buffer, in bytes
1590  * @rcvsize: requested size of receive buffer, in bytes
1591  *
1592  * Set socket send and receive buffer size limits.
1593  */
1594 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1595 {
1596         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1597
1598         transport->sndsize = 0;
1599         if (sndsize)
1600                 transport->sndsize = sndsize + 1024;
1601         transport->rcvsize = 0;
1602         if (rcvsize)
1603                 transport->rcvsize = rcvsize + 1024;
1604
1605         xs_udp_do_set_buffer_size(xprt);
1606 }
1607
1608 /**
1609  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1610  * @xprt: controlling transport
1611  * @task: task that timed out
1612  *
1613  * Adjust the congestion window after a retransmit timeout has occurred.
1614  */
1615 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1616 {
1617         spin_lock_bh(&xprt->transport_lock);
1618         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1619         spin_unlock_bh(&xprt->transport_lock);
1620 }
1621
1622 static int xs_get_random_port(void)
1623 {
1624         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1625         unsigned short range;
1626         unsigned short rand;
1627
1628         if (max < min)
1629                 return -EADDRINUSE;
1630         range = max - min + 1;
1631         rand = (unsigned short) prandom_u32() % range;
1632         return rand + min;
1633 }
1634
1635 /**
1636  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1637  * @sock: socket
1638  *
1639  * Note that this function has to be called on all sockets that share the
1640  * same port, and it must be called before binding.
1641  */
1642 static void xs_sock_set_reuseport(struct socket *sock)
1643 {
1644         int opt = 1;
1645
1646         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1647                         (char *)&opt, sizeof(opt));
1648 }
1649
1650 static unsigned short xs_sock_getport(struct socket *sock)
1651 {
1652         struct sockaddr_storage buf;
1653         unsigned short port = 0;
1654
1655         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1656                 goto out;
1657         switch (buf.ss_family) {
1658         case AF_INET6:
1659                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1660                 break;
1661         case AF_INET:
1662                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1663         }
1664 out:
1665         return port;
1666 }
1667
1668 /**
1669  * xs_set_port - reset the port number in the remote endpoint address
1670  * @xprt: generic transport
1671  * @port: new port number
1672  *
1673  */
1674 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1675 {
1676         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1677
1678         rpc_set_port(xs_addr(xprt), port);
1679         xs_update_peer_port(xprt);
1680 }
1681
1682 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1683 {
1684         if (transport->srcport == 0)
1685                 transport->srcport = xs_sock_getport(sock);
1686 }
1687
1688 static int xs_get_srcport(struct sock_xprt *transport)
1689 {
1690         int port = transport->srcport;
1691
1692         if (port == 0 && transport->xprt.resvport)
1693                 port = xs_get_random_port();
1694         return port;
1695 }
1696
1697 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1698 {
1699         if (transport->srcport != 0)
1700                 transport->srcport = 0;
1701         if (!transport->xprt.resvport)
1702                 return 0;
1703         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1704                 return xprt_max_resvport;
1705         return --port;
1706 }
1707 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1708 {
1709         struct sockaddr_storage myaddr;
1710         int err, nloop = 0;
1711         int port = xs_get_srcport(transport);
1712         unsigned short last;
1713
1714         /*
1715          * If we are asking for any ephemeral port (i.e. port == 0 &&
1716          * transport->xprt.resvport == 0), don't bind.  Let the local
1717          * port selection happen implicitly when the socket is used
1718          * (for example at connect time).
1719          *
1720          * This ensures that we can continue to establish TCP
1721          * connections even when all local ephemeral ports are already
1722          * a part of some TCP connection.  This makes no difference
1723          * for UDP sockets, but also doens't harm them.
1724          *
1725          * If we're asking for any reserved port (i.e. port == 0 &&
1726          * transport->xprt.resvport == 1) xs_get_srcport above will
1727          * ensure that port is non-zero and we will bind as needed.
1728          */
1729         if (port <= 0)
1730                 return port;
1731
1732         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1733         do {
1734                 rpc_set_port((struct sockaddr *)&myaddr, port);
1735                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1736                                 transport->xprt.addrlen);
1737                 if (err == 0) {
1738                         transport->srcport = port;
1739                         break;
1740                 }
1741                 last = port;
1742                 port = xs_next_srcport(transport, port);
1743                 if (port > last)
1744                         nloop++;
1745         } while (err == -EADDRINUSE && nloop != 2);
1746
1747         if (myaddr.ss_family == AF_INET)
1748                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1749                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1750                                 port, err ? "failed" : "ok", err);
1751         else
1752                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1753                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1754                                 port, err ? "failed" : "ok", err);
1755         return err;
1756 }
1757
1758 /*
1759  * We don't support autobind on AF_LOCAL sockets
1760  */
1761 static void xs_local_rpcbind(struct rpc_task *task)
1762 {
1763         xprt_set_bound(task->tk_xprt);
1764 }
1765
1766 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1767 {
1768 }
1769
1770 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1771 static struct lock_class_key xs_key[2];
1772 static struct lock_class_key xs_slock_key[2];
1773
1774 static inline void xs_reclassify_socketu(struct socket *sock)
1775 {
1776         struct sock *sk = sock->sk;
1777
1778         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1779                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1780 }
1781
1782 static inline void xs_reclassify_socket4(struct socket *sock)
1783 {
1784         struct sock *sk = sock->sk;
1785
1786         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1787                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1788 }
1789
1790 static inline void xs_reclassify_socket6(struct socket *sock)
1791 {
1792         struct sock *sk = sock->sk;
1793
1794         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1795                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1796 }
1797
1798 static inline void xs_reclassify_socket(int family, struct socket *sock)
1799 {
1800         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1801                 return;
1802
1803         switch (family) {
1804         case AF_LOCAL:
1805                 xs_reclassify_socketu(sock);
1806                 break;
1807         case AF_INET:
1808                 xs_reclassify_socket4(sock);
1809                 break;
1810         case AF_INET6:
1811                 xs_reclassify_socket6(sock);
1812                 break;
1813         }
1814 }
1815 #else
1816 static inline void xs_reclassify_socket(int family, struct socket *sock)
1817 {
1818 }
1819 #endif
1820
1821 static void xs_dummy_setup_socket(struct work_struct *work)
1822 {
1823 }
1824
1825 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1826                 struct sock_xprt *transport, int family, int type,
1827                 int protocol, bool reuseport)
1828 {
1829         struct socket *sock;
1830         int err;
1831
1832         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1833         if (err < 0) {
1834                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1835                                 protocol, -err);
1836                 goto out;
1837         }
1838         xs_reclassify_socket(family, sock);
1839
1840         if (reuseport)
1841                 xs_sock_set_reuseport(sock);
1842
1843         err = xs_bind(transport, sock);
1844         if (err) {
1845                 sock_release(sock);
1846                 goto out;
1847         }
1848
1849         return sock;
1850 out:
1851         return ERR_PTR(err);
1852 }
1853
1854 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1855                                       struct socket *sock)
1856 {
1857         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1858                                                                         xprt);
1859
1860         if (!transport->inet) {
1861                 struct sock *sk = sock->sk;
1862
1863                 write_lock_bh(&sk->sk_callback_lock);
1864
1865                 xs_save_old_callbacks(transport, sk);
1866
1867                 sk->sk_user_data = xprt;
1868                 sk->sk_data_ready = xs_data_ready;
1869                 sk->sk_write_space = xs_udp_write_space;
1870                 sock_set_flag(sk, SOCK_FASYNC);
1871                 sk->sk_error_report = xs_error_report;
1872                 sk->sk_allocation = GFP_NOIO;
1873
1874                 xprt_clear_connected(xprt);
1875
1876                 /* Reset to new socket */
1877                 transport->sock = sock;
1878                 transport->inet = sk;
1879
1880                 write_unlock_bh(&sk->sk_callback_lock);
1881         }
1882
1883         xs_stream_reset_connect(transport);
1884
1885         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1886 }
1887
1888 /**
1889  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1890  * @transport: socket transport to connect
1891  */
1892 static int xs_local_setup_socket(struct sock_xprt *transport)
1893 {
1894         struct rpc_xprt *xprt = &transport->xprt;
1895         struct socket *sock;
1896         int status = -EIO;
1897
1898         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1899                                         SOCK_STREAM, 0, &sock, 1);
1900         if (status < 0) {
1901                 dprintk("RPC:       can't create AF_LOCAL "
1902                         "transport socket (%d).\n", -status);
1903                 goto out;
1904         }
1905         xs_reclassify_socket(AF_LOCAL, sock);
1906
1907         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1908                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1909
1910         status = xs_local_finish_connecting(xprt, sock);
1911         trace_rpc_socket_connect(xprt, sock, status);
1912         switch (status) {
1913         case 0:
1914                 dprintk("RPC:       xprt %p connected to %s\n",
1915                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1916                 xprt->stat.connect_count++;
1917                 xprt->stat.connect_time += (long)jiffies -
1918                                            xprt->stat.connect_start;
1919                 xprt_set_connected(xprt);
1920         case -ENOBUFS:
1921                 break;
1922         case -ENOENT:
1923                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1924                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1925                 break;
1926         case -ECONNREFUSED:
1927                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1928                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1929                 break;
1930         default:
1931                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1932                                 __func__, -status,
1933                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1934         }
1935
1936 out:
1937         xprt_clear_connecting(xprt);
1938         xprt_wake_pending_tasks(xprt, status);
1939         return status;
1940 }
1941
1942 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1943 {
1944         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1945         int ret;
1946
1947          if (RPC_IS_ASYNC(task)) {
1948                 /*
1949                  * We want the AF_LOCAL connect to be resolved in the
1950                  * filesystem namespace of the process making the rpc
1951                  * call.  Thus we connect synchronously.
1952                  *
1953                  * If we want to support asynchronous AF_LOCAL calls,
1954                  * we'll need to figure out how to pass a namespace to
1955                  * connect.
1956                  */
1957                 rpc_exit(task, -ENOTCONN);
1958                 return;
1959         }
1960         ret = xs_local_setup_socket(transport);
1961         if (ret && !RPC_IS_SOFTCONN(task))
1962                 msleep_interruptible(15000);
1963 }
1964
1965 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1966 /*
1967  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1968  * know that we have exclusive access to the socket), to guard against
1969  * races with xs_reset_transport.
1970  */
1971 static void xs_set_memalloc(struct rpc_xprt *xprt)
1972 {
1973         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1974                         xprt);
1975
1976         /*
1977          * If there's no sock, then we have nothing to set. The
1978          * reconnecting process will get it for us.
1979          */
1980         if (!transport->inet)
1981                 return;
1982         if (atomic_read(&xprt->swapper))
1983                 sk_set_memalloc(transport->inet);
1984 }
1985
1986 /**
1987  * xs_enable_swap - Tag this transport as being used for swap.
1988  * @xprt: transport to tag
1989  *
1990  * Take a reference to this transport on behalf of the rpc_clnt, and
1991  * optionally mark it for swapping if it wasn't already.
1992  */
1993 static int
1994 xs_enable_swap(struct rpc_xprt *xprt)
1995 {
1996         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1997
1998         if (atomic_inc_return(&xprt->swapper) != 1)
1999                 return 0;
2000         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2001                 return -ERESTARTSYS;
2002         if (xs->inet)
2003                 sk_set_memalloc(xs->inet);
2004         xprt_release_xprt(xprt, NULL);
2005         return 0;
2006 }
2007
2008 /**
2009  * xs_disable_swap - Untag this transport as being used for swap.
2010  * @xprt: transport to tag
2011  *
2012  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2013  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2014  */
2015 static void
2016 xs_disable_swap(struct rpc_xprt *xprt)
2017 {
2018         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2019
2020         if (!atomic_dec_and_test(&xprt->swapper))
2021                 return;
2022         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2023                 return;
2024         if (xs->inet)
2025                 sk_clear_memalloc(xs->inet);
2026         xprt_release_xprt(xprt, NULL);
2027 }
2028 #else
2029 static void xs_set_memalloc(struct rpc_xprt *xprt)
2030 {
2031 }
2032
2033 static int
2034 xs_enable_swap(struct rpc_xprt *xprt)
2035 {
2036         return -EINVAL;
2037 }
2038
2039 static void
2040 xs_disable_swap(struct rpc_xprt *xprt)
2041 {
2042 }
2043 #endif
2044
2045 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2046 {
2047         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2048
2049         if (!transport->inet) {
2050                 struct sock *sk = sock->sk;
2051
2052                 write_lock_bh(&sk->sk_callback_lock);
2053
2054                 xs_save_old_callbacks(transport, sk);
2055
2056                 sk->sk_user_data = xprt;
2057                 sk->sk_data_ready = xs_data_ready;
2058                 sk->sk_write_space = xs_udp_write_space;
2059                 sock_set_flag(sk, SOCK_FASYNC);
2060                 sk->sk_allocation = GFP_NOIO;
2061
2062                 xprt_set_connected(xprt);
2063
2064                 /* Reset to new socket */
2065                 transport->sock = sock;
2066                 transport->inet = sk;
2067
2068                 xs_set_memalloc(xprt);
2069
2070                 write_unlock_bh(&sk->sk_callback_lock);
2071         }
2072         xs_udp_do_set_buffer_size(xprt);
2073
2074         xprt->stat.connect_start = jiffies;
2075 }
2076
2077 static void xs_udp_setup_socket(struct work_struct *work)
2078 {
2079         struct sock_xprt *transport =
2080                 container_of(work, struct sock_xprt, connect_worker.work);
2081         struct rpc_xprt *xprt = &transport->xprt;
2082         struct socket *sock;
2083         int status = -EIO;
2084
2085         sock = xs_create_sock(xprt, transport,
2086                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2087                         IPPROTO_UDP, false);
2088         if (IS_ERR(sock))
2089                 goto out;
2090
2091         dprintk("RPC:       worker connecting xprt %p via %s to "
2092                                 "%s (port %s)\n", xprt,
2093                         xprt->address_strings[RPC_DISPLAY_PROTO],
2094                         xprt->address_strings[RPC_DISPLAY_ADDR],
2095                         xprt->address_strings[RPC_DISPLAY_PORT]);
2096
2097         xs_udp_finish_connecting(xprt, sock);
2098         trace_rpc_socket_connect(xprt, sock, 0);
2099         status = 0;
2100 out:
2101         xprt_clear_connecting(xprt);
2102         xprt_unlock_connect(xprt, transport);
2103         xprt_wake_pending_tasks(xprt, status);
2104 }
2105
2106 /**
2107  * xs_tcp_shutdown - gracefully shut down a TCP socket
2108  * @xprt: transport
2109  *
2110  * Initiates a graceful shutdown of the TCP socket by calling the
2111  * equivalent of shutdown(SHUT_RDWR);
2112  */
2113 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2114 {
2115         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2116         struct socket *sock = transport->sock;
2117         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2118
2119         if (sock == NULL)
2120                 return;
2121         switch (skst) {
2122         default:
2123                 kernel_sock_shutdown(sock, SHUT_RDWR);
2124                 trace_rpc_socket_shutdown(xprt, sock);
2125                 break;
2126         case TCP_CLOSE:
2127         case TCP_TIME_WAIT:
2128                 xs_reset_transport(transport);
2129         }
2130 }
2131
2132 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2133                 struct socket *sock)
2134 {
2135         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2136         unsigned int keepidle;
2137         unsigned int keepcnt;
2138         unsigned int opt_on = 1;
2139         unsigned int timeo;
2140
2141         spin_lock_bh(&xprt->transport_lock);
2142         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2143         keepcnt = xprt->timeout->to_retries + 1;
2144         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2145                 (xprt->timeout->to_retries + 1);
2146         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2147         spin_unlock_bh(&xprt->transport_lock);
2148
2149         /* TCP Keepalive options */
2150         kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2151                         (char *)&opt_on, sizeof(opt_on));
2152         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2153                         (char *)&keepidle, sizeof(keepidle));
2154         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2155                         (char *)&keepidle, sizeof(keepidle));
2156         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2157                         (char *)&keepcnt, sizeof(keepcnt));
2158
2159         /* TCP user timeout (see RFC5482) */
2160         kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2161                         (char *)&timeo, sizeof(timeo));
2162 }
2163
2164 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2165                 unsigned long connect_timeout,
2166                 unsigned long reconnect_timeout)
2167 {
2168         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2169         struct rpc_timeout to;
2170         unsigned long initval;
2171
2172         spin_lock_bh(&xprt->transport_lock);
2173         if (reconnect_timeout < xprt->max_reconnect_timeout)
2174                 xprt->max_reconnect_timeout = reconnect_timeout;
2175         if (connect_timeout < xprt->connect_timeout) {
2176                 memcpy(&to, xprt->timeout, sizeof(to));
2177                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2178                 /* Arbitrary lower limit */
2179                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2180                         initval = XS_TCP_INIT_REEST_TO << 1;
2181                 to.to_initval = initval;
2182                 to.to_maxval = initval;
2183                 memcpy(&transport->tcp_timeout, &to,
2184                                 sizeof(transport->tcp_timeout));
2185                 xprt->timeout = &transport->tcp_timeout;
2186                 xprt->connect_timeout = connect_timeout;
2187         }
2188         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2189         spin_unlock_bh(&xprt->transport_lock);
2190 }
2191
2192 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2193 {
2194         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2195         int ret = -ENOTCONN;
2196
2197         if (!transport->inet) {
2198                 struct sock *sk = sock->sk;
2199                 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2200
2201                 /* Avoid temporary address, they are bad for long-lived
2202                  * connections such as NFS mounts.
2203                  * RFC4941, section 3.6 suggests that:
2204                  *    Individual applications, which have specific
2205                  *    knowledge about the normal duration of connections,
2206                  *    MAY override this as appropriate.
2207                  */
2208                 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2209                                 (char *)&addr_pref, sizeof(addr_pref));
2210
2211                 xs_tcp_set_socket_timeouts(xprt, sock);
2212
2213                 write_lock_bh(&sk->sk_callback_lock);
2214
2215                 xs_save_old_callbacks(transport, sk);
2216
2217                 sk->sk_user_data = xprt;
2218                 sk->sk_data_ready = xs_data_ready;
2219                 sk->sk_state_change = xs_tcp_state_change;
2220                 sk->sk_write_space = xs_tcp_write_space;
2221                 sock_set_flag(sk, SOCK_FASYNC);
2222                 sk->sk_error_report = xs_error_report;
2223                 sk->sk_allocation = GFP_NOIO;
2224
2225                 /* socket options */
2226                 sock_reset_flag(sk, SOCK_LINGER);
2227                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2228
2229                 xprt_clear_connected(xprt);
2230
2231                 /* Reset to new socket */
2232                 transport->sock = sock;
2233                 transport->inet = sk;
2234
2235                 write_unlock_bh(&sk->sk_callback_lock);
2236         }
2237
2238         if (!xprt_bound(xprt))
2239                 goto out;
2240
2241         xs_set_memalloc(xprt);
2242
2243         /* Reset TCP record info */
2244         xs_stream_reset_connect(transport);
2245
2246         /* Tell the socket layer to start connecting... */
2247         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2248         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2249         switch (ret) {
2250         case 0:
2251                 xs_set_srcport(transport, sock);
2252                 /* fall through */
2253         case -EINPROGRESS:
2254                 /* SYN_SENT! */
2255                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2256                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2257                 break;
2258         case -EADDRNOTAVAIL:
2259                 /* Source port number is unavailable. Try a new one! */
2260                 transport->srcport = 0;
2261         }
2262 out:
2263         return ret;
2264 }
2265
2266 /**
2267  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2268  * @work: queued work item
2269  *
2270  * Invoked by a work queue tasklet.
2271  */
2272 static void xs_tcp_setup_socket(struct work_struct *work)
2273 {
2274         struct sock_xprt *transport =
2275                 container_of(work, struct sock_xprt, connect_worker.work);
2276         struct socket *sock = transport->sock;
2277         struct rpc_xprt *xprt = &transport->xprt;
2278         int status = -EIO;
2279
2280         if (!sock) {
2281                 sock = xs_create_sock(xprt, transport,
2282                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2283                                 IPPROTO_TCP, true);
2284                 if (IS_ERR(sock)) {
2285                         status = PTR_ERR(sock);
2286                         goto out;
2287                 }
2288         }
2289
2290         dprintk("RPC:       worker connecting xprt %p via %s to "
2291                                 "%s (port %s)\n", xprt,
2292                         xprt->address_strings[RPC_DISPLAY_PROTO],
2293                         xprt->address_strings[RPC_DISPLAY_ADDR],
2294                         xprt->address_strings[RPC_DISPLAY_PORT]);
2295
2296         status = xs_tcp_finish_connecting(xprt, sock);
2297         trace_rpc_socket_connect(xprt, sock, status);
2298         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2299                         xprt, -status, xprt_connected(xprt),
2300                         sock->sk->sk_state);
2301         switch (status) {
2302         default:
2303                 printk("%s: connect returned unhandled error %d\n",
2304                         __func__, status);
2305                 /* fall through */
2306         case -EADDRNOTAVAIL:
2307                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2308                  * and retry
2309                  */
2310                 xs_tcp_force_close(xprt);
2311                 break;
2312         case 0:
2313         case -EINPROGRESS:
2314         case -EALREADY:
2315                 xprt_unlock_connect(xprt, transport);
2316                 return;
2317         case -EINVAL:
2318                 /* Happens, for instance, if the user specified a link
2319                  * local IPv6 address without a scope-id.
2320                  */
2321         case -ECONNREFUSED:
2322         case -ECONNRESET:
2323         case -ENETDOWN:
2324         case -ENETUNREACH:
2325         case -EHOSTUNREACH:
2326         case -EADDRINUSE:
2327         case -ENOBUFS:
2328                 /*
2329                  * xs_tcp_force_close() wakes tasks with -EIO.
2330                  * We need to wake them first to ensure the
2331                  * correct error code.
2332                  */
2333                 xprt_wake_pending_tasks(xprt, status);
2334                 xs_tcp_force_close(xprt);
2335                 goto out;
2336         }
2337         status = -EAGAIN;
2338 out:
2339         xprt_clear_connecting(xprt);
2340         xprt_unlock_connect(xprt, transport);
2341         xprt_wake_pending_tasks(xprt, status);
2342 }
2343
2344 static unsigned long xs_reconnect_delay(const struct rpc_xprt *xprt)
2345 {
2346         unsigned long start, now = jiffies;
2347
2348         start = xprt->stat.connect_start + xprt->reestablish_timeout;
2349         if (time_after(start, now))
2350                 return start - now;
2351         return 0;
2352 }
2353
2354 static void xs_reconnect_backoff(struct rpc_xprt *xprt)
2355 {
2356         xprt->reestablish_timeout <<= 1;
2357         if (xprt->reestablish_timeout > xprt->max_reconnect_timeout)
2358                 xprt->reestablish_timeout = xprt->max_reconnect_timeout;
2359         if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2360                 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2361 }
2362
2363 /**
2364  * xs_connect - connect a socket to a remote endpoint
2365  * @xprt: pointer to transport structure
2366  * @task: address of RPC task that manages state of connect request
2367  *
2368  * TCP: If the remote end dropped the connection, delay reconnecting.
2369  *
2370  * UDP socket connects are synchronous, but we use a work queue anyway
2371  * to guarantee that even unprivileged user processes can set up a
2372  * socket on a privileged port.
2373  *
2374  * If a UDP socket connect fails, the delay behavior here prevents
2375  * retry floods (hard mounts).
2376  */
2377 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2378 {
2379         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2380         unsigned long delay = 0;
2381
2382         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2383
2384         if (transport->sock != NULL) {
2385                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2386                                 "seconds\n",
2387                                 xprt, xprt->reestablish_timeout / HZ);
2388
2389                 /* Start by resetting any existing state */
2390                 xs_reset_transport(transport);
2391
2392                 delay = xs_reconnect_delay(xprt);
2393                 xs_reconnect_backoff(xprt);
2394
2395         } else
2396                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2397
2398         queue_delayed_work(xprtiod_workqueue,
2399                         &transport->connect_worker,
2400                         delay);
2401 }
2402
2403 /**
2404  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2405  * @xprt: rpc_xprt struct containing statistics
2406  * @seq: output file
2407  *
2408  */
2409 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2410 {
2411         long idle_time = 0;
2412
2413         if (xprt_connected(xprt))
2414                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2415
2416         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2417                         "%llu %llu %lu %llu %llu\n",
2418                         xprt->stat.bind_count,
2419                         xprt->stat.connect_count,
2420                         xprt->stat.connect_time / HZ,
2421                         idle_time,
2422                         xprt->stat.sends,
2423                         xprt->stat.recvs,
2424                         xprt->stat.bad_xids,
2425                         xprt->stat.req_u,
2426                         xprt->stat.bklog_u,
2427                         xprt->stat.max_slots,
2428                         xprt->stat.sending_u,
2429                         xprt->stat.pending_u);
2430 }
2431
2432 /**
2433  * xs_udp_print_stats - display UDP socket-specifc stats
2434  * @xprt: rpc_xprt struct containing statistics
2435  * @seq: output file
2436  *
2437  */
2438 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2439 {
2440         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2441
2442         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2443                         "%lu %llu %llu\n",
2444                         transport->srcport,
2445                         xprt->stat.bind_count,
2446                         xprt->stat.sends,
2447                         xprt->stat.recvs,
2448                         xprt->stat.bad_xids,
2449                         xprt->stat.req_u,
2450                         xprt->stat.bklog_u,
2451                         xprt->stat.max_slots,
2452                         xprt->stat.sending_u,
2453                         xprt->stat.pending_u);
2454 }
2455
2456 /**
2457  * xs_tcp_print_stats - display TCP socket-specifc stats
2458  * @xprt: rpc_xprt struct containing statistics
2459  * @seq: output file
2460  *
2461  */
2462 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2463 {
2464         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2465         long idle_time = 0;
2466
2467         if (xprt_connected(xprt))
2468                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2469
2470         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2471                         "%llu %llu %lu %llu %llu\n",
2472                         transport->srcport,
2473                         xprt->stat.bind_count,
2474                         xprt->stat.connect_count,
2475                         xprt->stat.connect_time / HZ,
2476                         idle_time,
2477                         xprt->stat.sends,
2478                         xprt->stat.recvs,
2479                         xprt->stat.bad_xids,
2480                         xprt->stat.req_u,
2481                         xprt->stat.bklog_u,
2482                         xprt->stat.max_slots,
2483                         xprt->stat.sending_u,
2484                         xprt->stat.pending_u);
2485 }
2486
2487 /*
2488  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2489  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2490  * to use the server side send routines.
2491  */
2492 static int bc_malloc(struct rpc_task *task)
2493 {
2494         struct rpc_rqst *rqst = task->tk_rqstp;
2495         size_t size = rqst->rq_callsize;
2496         struct page *page;
2497         struct rpc_buffer *buf;
2498
2499         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2500                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2501                           size);
2502                 return -EINVAL;
2503         }
2504
2505         page = alloc_page(GFP_KERNEL);
2506         if (!page)
2507                 return -ENOMEM;
2508
2509         buf = page_address(page);
2510         buf->len = PAGE_SIZE;
2511
2512         rqst->rq_buffer = buf->data;
2513         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2514         return 0;
2515 }
2516
2517 /*
2518  * Free the space allocated in the bc_alloc routine
2519  */
2520 static void bc_free(struct rpc_task *task)
2521 {
2522         void *buffer = task->tk_rqstp->rq_buffer;
2523         struct rpc_buffer *buf;
2524
2525         buf = container_of(buffer, struct rpc_buffer, data);
2526         free_page((unsigned long)buf);
2527 }
2528
2529 /*
2530  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2531  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2532  */
2533 static int bc_sendto(struct rpc_rqst *req)
2534 {
2535         int len;
2536         struct xdr_buf *xbufp = &req->rq_snd_buf;
2537         struct rpc_xprt *xprt = req->rq_xprt;
2538         struct sock_xprt *transport =
2539                                 container_of(xprt, struct sock_xprt, xprt);
2540         struct socket *sock = transport->sock;
2541         unsigned long headoff;
2542         unsigned long tailoff;
2543
2544         xs_encode_stream_record_marker(xbufp);
2545
2546         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2547         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2548         len = svc_send_common(sock, xbufp,
2549                               virt_to_page(xbufp->head[0].iov_base), headoff,
2550                               xbufp->tail[0].iov_base, tailoff);
2551
2552         if (len != xbufp->len) {
2553                 printk(KERN_NOTICE "Error sending entire callback!\n");
2554                 len = -EAGAIN;
2555         }
2556
2557         return len;
2558 }
2559
2560 /*
2561  * The send routine. Borrows from svc_send
2562  */
2563 static int bc_send_request(struct rpc_rqst *req)
2564 {
2565         struct svc_xprt *xprt;
2566         int len;
2567
2568         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2569         /*
2570          * Get the server socket associated with this callback xprt
2571          */
2572         xprt = req->rq_xprt->bc_xprt;
2573
2574         /*
2575          * Grab the mutex to serialize data as the connection is shared
2576          * with the fore channel
2577          */
2578         mutex_lock(&xprt->xpt_mutex);
2579         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2580                 len = -ENOTCONN;
2581         else
2582                 len = bc_sendto(req);
2583         mutex_unlock(&xprt->xpt_mutex);
2584
2585         if (len > 0)
2586                 len = 0;
2587
2588         return len;
2589 }
2590
2591 /*
2592  * The close routine. Since this is client initiated, we do nothing
2593  */
2594
2595 static void bc_close(struct rpc_xprt *xprt)
2596 {
2597 }
2598
2599 /*
2600  * The xprt destroy routine. Again, because this connection is client
2601  * initiated, we do nothing
2602  */
2603
2604 static void bc_destroy(struct rpc_xprt *xprt)
2605 {
2606         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2607
2608         xs_xprt_free(xprt);
2609         module_put(THIS_MODULE);
2610 }
2611
2612 static const struct rpc_xprt_ops xs_local_ops = {
2613         .reserve_xprt           = xprt_reserve_xprt,
2614         .release_xprt           = xprt_release_xprt,
2615         .alloc_slot             = xprt_alloc_slot,
2616         .free_slot              = xprt_free_slot,
2617         .rpcbind                = xs_local_rpcbind,
2618         .set_port               = xs_local_set_port,
2619         .connect                = xs_local_connect,
2620         .buf_alloc              = rpc_malloc,
2621         .buf_free               = rpc_free,
2622         .prepare_request        = xs_stream_prepare_request,
2623         .send_request           = xs_local_send_request,
2624         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2625         .close                  = xs_close,
2626         .destroy                = xs_destroy,
2627         .print_stats            = xs_local_print_stats,
2628         .enable_swap            = xs_enable_swap,
2629         .disable_swap           = xs_disable_swap,
2630 };
2631
2632 static const struct rpc_xprt_ops xs_udp_ops = {
2633         .set_buffer_size        = xs_udp_set_buffer_size,
2634         .reserve_xprt           = xprt_reserve_xprt_cong,
2635         .release_xprt           = xprt_release_xprt_cong,
2636         .alloc_slot             = xprt_alloc_slot,
2637         .free_slot              = xprt_free_slot,
2638         .rpcbind                = rpcb_getport_async,
2639         .set_port               = xs_set_port,
2640         .connect                = xs_connect,
2641         .buf_alloc              = rpc_malloc,
2642         .buf_free               = rpc_free,
2643         .send_request           = xs_udp_send_request,
2644         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2645         .timer                  = xs_udp_timer,
2646         .release_request        = xprt_release_rqst_cong,
2647         .close                  = xs_close,
2648         .destroy                = xs_destroy,
2649         .print_stats            = xs_udp_print_stats,
2650         .enable_swap            = xs_enable_swap,
2651         .disable_swap           = xs_disable_swap,
2652         .inject_disconnect      = xs_inject_disconnect,
2653 };
2654
2655 static const struct rpc_xprt_ops xs_tcp_ops = {
2656         .reserve_xprt           = xprt_reserve_xprt,
2657         .release_xprt           = xprt_release_xprt,
2658         .alloc_slot             = xprt_alloc_slot,
2659         .free_slot              = xprt_free_slot,
2660         .rpcbind                = rpcb_getport_async,
2661         .set_port               = xs_set_port,
2662         .connect                = xs_connect,
2663         .buf_alloc              = rpc_malloc,
2664         .buf_free               = rpc_free,
2665         .prepare_request        = xs_stream_prepare_request,
2666         .send_request           = xs_tcp_send_request,
2667         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2668         .close                  = xs_tcp_shutdown,
2669         .destroy                = xs_destroy,
2670         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2671         .print_stats            = xs_tcp_print_stats,
2672         .enable_swap            = xs_enable_swap,
2673         .disable_swap           = xs_disable_swap,
2674         .inject_disconnect      = xs_inject_disconnect,
2675 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2676         .bc_setup               = xprt_setup_bc,
2677         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2678         .bc_free_rqst           = xprt_free_bc_rqst,
2679         .bc_destroy             = xprt_destroy_bc,
2680 #endif
2681 };
2682
2683 /*
2684  * The rpc_xprt_ops for the server backchannel
2685  */
2686
2687 static const struct rpc_xprt_ops bc_tcp_ops = {
2688         .reserve_xprt           = xprt_reserve_xprt,
2689         .release_xprt           = xprt_release_xprt,
2690         .alloc_slot             = xprt_alloc_slot,
2691         .free_slot              = xprt_free_slot,
2692         .buf_alloc              = bc_malloc,
2693         .buf_free               = bc_free,
2694         .send_request           = bc_send_request,
2695         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2696         .close                  = bc_close,
2697         .destroy                = bc_destroy,
2698         .print_stats            = xs_tcp_print_stats,
2699         .enable_swap            = xs_enable_swap,
2700         .disable_swap           = xs_disable_swap,
2701         .inject_disconnect      = xs_inject_disconnect,
2702 };
2703
2704 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2705 {
2706         static const struct sockaddr_in sin = {
2707                 .sin_family             = AF_INET,
2708                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2709         };
2710         static const struct sockaddr_in6 sin6 = {
2711                 .sin6_family            = AF_INET6,
2712                 .sin6_addr              = IN6ADDR_ANY_INIT,
2713         };
2714
2715         switch (family) {
2716         case AF_LOCAL:
2717                 break;
2718         case AF_INET:
2719                 memcpy(sap, &sin, sizeof(sin));
2720                 break;
2721         case AF_INET6:
2722                 memcpy(sap, &sin6, sizeof(sin6));
2723                 break;
2724         default:
2725                 dprintk("RPC:       %s: Bad address family\n", __func__);
2726                 return -EAFNOSUPPORT;
2727         }
2728         return 0;
2729 }
2730
2731 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2732                                       unsigned int slot_table_size,
2733                                       unsigned int max_slot_table_size)
2734 {
2735         struct rpc_xprt *xprt;
2736         struct sock_xprt *new;
2737
2738         if (args->addrlen > sizeof(xprt->addr)) {
2739                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2740                 return ERR_PTR(-EBADF);
2741         }
2742
2743         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2744                         max_slot_table_size);
2745         if (xprt == NULL) {
2746                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2747                                 "rpc_xprt\n");
2748                 return ERR_PTR(-ENOMEM);
2749         }
2750
2751         new = container_of(xprt, struct sock_xprt, xprt);
2752         mutex_init(&new->recv_mutex);
2753         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2754         xprt->addrlen = args->addrlen;
2755         if (args->srcaddr)
2756                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2757         else {
2758                 int err;
2759                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2760                                         (struct sockaddr *)&new->srcaddr);
2761                 if (err != 0) {
2762                         xprt_free(xprt);
2763                         return ERR_PTR(err);
2764                 }
2765         }
2766
2767         return xprt;
2768 }
2769
2770 static const struct rpc_timeout xs_local_default_timeout = {
2771         .to_initval = 10 * HZ,
2772         .to_maxval = 10 * HZ,
2773         .to_retries = 2,
2774 };
2775
2776 /**
2777  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2778  * @args: rpc transport creation arguments
2779  *
2780  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2781  */
2782 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2783 {
2784         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2785         struct sock_xprt *transport;
2786         struct rpc_xprt *xprt;
2787         struct rpc_xprt *ret;
2788
2789         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2790                         xprt_max_tcp_slot_table_entries);
2791         if (IS_ERR(xprt))
2792                 return xprt;
2793         transport = container_of(xprt, struct sock_xprt, xprt);
2794
2795         xprt->prot = 0;
2796         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2797         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2798
2799         xprt->bind_timeout = XS_BIND_TO;
2800         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2801         xprt->idle_timeout = XS_IDLE_DISC_TO;
2802
2803         xprt->ops = &xs_local_ops;
2804         xprt->timeout = &xs_local_default_timeout;
2805
2806         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2807         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2808
2809         switch (sun->sun_family) {
2810         case AF_LOCAL:
2811                 if (sun->sun_path[0] != '/') {
2812                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2813                                         sun->sun_path);
2814                         ret = ERR_PTR(-EINVAL);
2815                         goto out_err;
2816                 }
2817                 xprt_set_bound(xprt);
2818                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2819                 ret = ERR_PTR(xs_local_setup_socket(transport));
2820                 if (ret)
2821                         goto out_err;
2822                 break;
2823         default:
2824                 ret = ERR_PTR(-EAFNOSUPPORT);
2825                 goto out_err;
2826         }
2827
2828         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2829                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2830
2831         if (try_module_get(THIS_MODULE))
2832                 return xprt;
2833         ret = ERR_PTR(-EINVAL);
2834 out_err:
2835         xs_xprt_free(xprt);
2836         return ret;
2837 }
2838
2839 static const struct rpc_timeout xs_udp_default_timeout = {
2840         .to_initval = 5 * HZ,
2841         .to_maxval = 30 * HZ,
2842         .to_increment = 5 * HZ,
2843         .to_retries = 5,
2844 };
2845
2846 /**
2847  * xs_setup_udp - Set up transport to use a UDP socket
2848  * @args: rpc transport creation arguments
2849  *
2850  */
2851 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2852 {
2853         struct sockaddr *addr = args->dstaddr;
2854         struct rpc_xprt *xprt;
2855         struct sock_xprt *transport;
2856         struct rpc_xprt *ret;
2857
2858         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2859                         xprt_udp_slot_table_entries);
2860         if (IS_ERR(xprt))
2861                 return xprt;
2862         transport = container_of(xprt, struct sock_xprt, xprt);
2863
2864         xprt->prot = IPPROTO_UDP;
2865         xprt->tsh_size = 0;
2866         /* XXX: header size can vary due to auth type, IPv6, etc. */
2867         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2868
2869         xprt->bind_timeout = XS_BIND_TO;
2870         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2871         xprt->idle_timeout = XS_IDLE_DISC_TO;
2872
2873         xprt->ops = &xs_udp_ops;
2874
2875         xprt->timeout = &xs_udp_default_timeout;
2876
2877         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2878         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2879
2880         switch (addr->sa_family) {
2881         case AF_INET:
2882                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2883                         xprt_set_bound(xprt);
2884
2885                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2886                 break;
2887         case AF_INET6:
2888                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2889                         xprt_set_bound(xprt);
2890
2891                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2892                 break;
2893         default:
2894                 ret = ERR_PTR(-EAFNOSUPPORT);
2895                 goto out_err;
2896         }
2897
2898         if (xprt_bound(xprt))
2899                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2900                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2901                                 xprt->address_strings[RPC_DISPLAY_PORT],
2902                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2903         else
2904                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2905                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2906                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2907
2908         if (try_module_get(THIS_MODULE))
2909                 return xprt;
2910         ret = ERR_PTR(-EINVAL);
2911 out_err:
2912         xs_xprt_free(xprt);
2913         return ret;
2914 }
2915
2916 static const struct rpc_timeout xs_tcp_default_timeout = {
2917         .to_initval = 60 * HZ,
2918         .to_maxval = 60 * HZ,
2919         .to_retries = 2,
2920 };
2921
2922 /**
2923  * xs_setup_tcp - Set up transport to use a TCP socket
2924  * @args: rpc transport creation arguments
2925  *
2926  */
2927 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2928 {
2929         struct sockaddr *addr = args->dstaddr;
2930         struct rpc_xprt *xprt;
2931         struct sock_xprt *transport;
2932         struct rpc_xprt *ret;
2933         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2934
2935         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2936                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2937
2938         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2939                         max_slot_table_size);
2940         if (IS_ERR(xprt))
2941                 return xprt;
2942         transport = container_of(xprt, struct sock_xprt, xprt);
2943
2944         xprt->prot = IPPROTO_TCP;
2945         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2946         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2947
2948         xprt->bind_timeout = XS_BIND_TO;
2949         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2950         xprt->idle_timeout = XS_IDLE_DISC_TO;
2951
2952         xprt->ops = &xs_tcp_ops;
2953         xprt->timeout = &xs_tcp_default_timeout;
2954
2955         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2956         xprt->connect_timeout = xprt->timeout->to_initval *
2957                 (xprt->timeout->to_retries + 1);
2958
2959         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2960         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2961
2962         switch (addr->sa_family) {
2963         case AF_INET:
2964                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2965                         xprt_set_bound(xprt);
2966
2967                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2968                 break;
2969         case AF_INET6:
2970                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2971                         xprt_set_bound(xprt);
2972
2973                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2974                 break;
2975         default:
2976                 ret = ERR_PTR(-EAFNOSUPPORT);
2977                 goto out_err;
2978         }
2979
2980         if (xprt_bound(xprt))
2981                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2982                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2983                                 xprt->address_strings[RPC_DISPLAY_PORT],
2984                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2985         else
2986                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2987                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2988                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2989
2990         if (try_module_get(THIS_MODULE))
2991                 return xprt;
2992         ret = ERR_PTR(-EINVAL);
2993 out_err:
2994         xs_xprt_free(xprt);
2995         return ret;
2996 }
2997
2998 /**
2999  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3000  * @args: rpc transport creation arguments
3001  *
3002  */
3003 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3004 {
3005         struct sockaddr *addr = args->dstaddr;
3006         struct rpc_xprt *xprt;
3007         struct sock_xprt *transport;
3008         struct svc_sock *bc_sock;
3009         struct rpc_xprt *ret;
3010
3011         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3012                         xprt_tcp_slot_table_entries);
3013         if (IS_ERR(xprt))
3014                 return xprt;
3015         transport = container_of(xprt, struct sock_xprt, xprt);
3016
3017         xprt->prot = IPPROTO_TCP;
3018         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3019         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3020         xprt->timeout = &xs_tcp_default_timeout;
3021
3022         /* backchannel */
3023         xprt_set_bound(xprt);
3024         xprt->bind_timeout = 0;
3025         xprt->reestablish_timeout = 0;
3026         xprt->idle_timeout = 0;
3027
3028         xprt->ops = &bc_tcp_ops;
3029
3030         switch (addr->sa_family) {
3031         case AF_INET:
3032                 xs_format_peer_addresses(xprt, "tcp",
3033                                          RPCBIND_NETID_TCP);
3034                 break;
3035         case AF_INET6:
3036                 xs_format_peer_addresses(xprt, "tcp",
3037                                    RPCBIND_NETID_TCP6);
3038                 break;
3039         default:
3040                 ret = ERR_PTR(-EAFNOSUPPORT);
3041                 goto out_err;
3042         }
3043
3044         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3045                         xprt->address_strings[RPC_DISPLAY_ADDR],
3046                         xprt->address_strings[RPC_DISPLAY_PORT],
3047                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3048
3049         /*
3050          * Once we've associated a backchannel xprt with a connection,
3051          * we want to keep it around as long as the connection lasts,
3052          * in case we need to start using it for a backchannel again;
3053          * this reference won't be dropped until bc_xprt is destroyed.
3054          */
3055         xprt_get(xprt);
3056         args->bc_xprt->xpt_bc_xprt = xprt;
3057         xprt->bc_xprt = args->bc_xprt;
3058         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3059         transport->sock = bc_sock->sk_sock;
3060         transport->inet = bc_sock->sk_sk;
3061
3062         /*
3063          * Since we don't want connections for the backchannel, we set
3064          * the xprt status to connected
3065          */
3066         xprt_set_connected(xprt);
3067
3068         if (try_module_get(THIS_MODULE))
3069                 return xprt;
3070
3071         args->bc_xprt->xpt_bc_xprt = NULL;
3072         args->bc_xprt->xpt_bc_xps = NULL;
3073         xprt_put(xprt);
3074         ret = ERR_PTR(-EINVAL);
3075 out_err:
3076         xs_xprt_free(xprt);
3077         return ret;
3078 }
3079
3080 static struct xprt_class        xs_local_transport = {
3081         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3082         .name           = "named UNIX socket",
3083         .owner          = THIS_MODULE,
3084         .ident          = XPRT_TRANSPORT_LOCAL,
3085         .setup          = xs_setup_local,
3086 };
3087
3088 static struct xprt_class        xs_udp_transport = {
3089         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3090         .name           = "udp",
3091         .owner          = THIS_MODULE,
3092         .ident          = XPRT_TRANSPORT_UDP,
3093         .setup          = xs_setup_udp,
3094 };
3095
3096 static struct xprt_class        xs_tcp_transport = {
3097         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3098         .name           = "tcp",
3099         .owner          = THIS_MODULE,
3100         .ident          = XPRT_TRANSPORT_TCP,
3101         .setup          = xs_setup_tcp,
3102 };
3103
3104 static struct xprt_class        xs_bc_tcp_transport = {
3105         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3106         .name           = "tcp NFSv4.1 backchannel",
3107         .owner          = THIS_MODULE,
3108         .ident          = XPRT_TRANSPORT_BC_TCP,
3109         .setup          = xs_setup_bc_tcp,
3110 };
3111
3112 /**
3113  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3114  *
3115  */
3116 int init_socket_xprt(void)
3117 {
3118         if (!sunrpc_table_header)
3119                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3120
3121         xprt_register_transport(&xs_local_transport);
3122         xprt_register_transport(&xs_udp_transport);
3123         xprt_register_transport(&xs_tcp_transport);
3124         xprt_register_transport(&xs_bc_tcp_transport);
3125
3126         return 0;
3127 }
3128
3129 /**
3130  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3131  *
3132  */
3133 void cleanup_socket_xprt(void)
3134 {
3135         if (sunrpc_table_header) {
3136                 unregister_sysctl_table(sunrpc_table_header);
3137                 sunrpc_table_header = NULL;
3138         }
3139
3140         xprt_unregister_transport(&xs_local_transport);
3141         xprt_unregister_transport(&xs_udp_transport);
3142         xprt_unregister_transport(&xs_tcp_transport);
3143         xprt_unregister_transport(&xs_bc_tcp_transport);
3144 }
3145
3146 static int param_set_uint_minmax(const char *val,
3147                 const struct kernel_param *kp,
3148                 unsigned int min, unsigned int max)
3149 {
3150         unsigned int num;
3151         int ret;
3152
3153         if (!val)
3154                 return -EINVAL;
3155         ret = kstrtouint(val, 0, &num);
3156         if (ret)
3157                 return ret;
3158         if (num < min || num > max)
3159                 return -EINVAL;
3160         *((unsigned int *)kp->arg) = num;
3161         return 0;
3162 }
3163
3164 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3165 {
3166         return param_set_uint_minmax(val, kp,
3167                         RPC_MIN_RESVPORT,
3168                         RPC_MAX_RESVPORT);
3169 }
3170
3171 static const struct kernel_param_ops param_ops_portnr = {
3172         .set = param_set_portnr,
3173         .get = param_get_uint,
3174 };
3175
3176 #define param_check_portnr(name, p) \
3177         __param_check(name, p, unsigned int);
3178
3179 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3180 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3181
3182 static int param_set_slot_table_size(const char *val,
3183                                      const struct kernel_param *kp)
3184 {
3185         return param_set_uint_minmax(val, kp,
3186                         RPC_MIN_SLOT_TABLE,
3187                         RPC_MAX_SLOT_TABLE);
3188 }
3189
3190 static const struct kernel_param_ops param_ops_slot_table_size = {
3191         .set = param_set_slot_table_size,
3192         .get = param_get_uint,
3193 };
3194
3195 #define param_check_slot_table_size(name, p) \
3196         __param_check(name, p, unsigned int);
3197
3198 static int param_set_max_slot_table_size(const char *val,
3199                                      const struct kernel_param *kp)
3200 {
3201         return param_set_uint_minmax(val, kp,
3202                         RPC_MIN_SLOT_TABLE,
3203                         RPC_MAX_SLOT_TABLE_LIMIT);
3204 }
3205
3206 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3207         .set = param_set_max_slot_table_size,
3208         .get = param_get_uint,
3209 };
3210
3211 #define param_check_max_slot_table_size(name, p) \
3212         __param_check(name, p, unsigned int);
3213
3214 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3215                    slot_table_size, 0644);
3216 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3217                    max_slot_table_size, 0644);
3218 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3219                    slot_table_size, 0644);