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/uio.h>
  52
  53 #include <trace/events/sunrpc.h>
  54
  55 #include "sunrpc.h"
  56
  57 static void xs_close(struct rpc_xprt *xprt);
  58 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  59                 struct socket *sock);
  60
  61 /*
  62  * xprtsock tunables
  63  */
  64 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  65 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  66 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  67
  68 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  69 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  70
  71 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  72
  73 #define XS_TCP_LINGER_TO        (15U * HZ)
  74 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  75
  76 /*
  77  * We can register our own files under /proc/sys/sunrpc by
  78  * calling register_sysctl_table() again.  The files in that
  79  * directory become the union of all files registered there.
  80  *
  81  * We simply need to make sure that we don't collide with
  82  * someone else's file names!
  83  */
  84
  85 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  86 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  87 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  88 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  89 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  90
  91 static struct ctl_table_header *sunrpc_table_header;
  92
  93 /*
  94  * FIXME: changing the UDP slot table size should also resize the UDP
  95  *        socket buffers for existing UDP transports
  96  */
  97 static struct ctl_table xs_tunables_table[] = {
  98         {
  99                 .procname       = "udp_slot_table_entries",
 100                 .data           = &xprt_udp_slot_table_entries,
 101                 .maxlen         = sizeof(unsigned int),
 102                 .mode           = 0644,
 103                 .proc_handler   = proc_dointvec_minmax,
 104                 .extra1         = &min_slot_table_size,
 105                 .extra2         = &max_slot_table_size
 106         },
 107         {
 108                 .procname       = "tcp_slot_table_entries",
 109                 .data           = &xprt_tcp_slot_table_entries,
 110                 .maxlen         = sizeof(unsigned int),
 111                 .mode           = 0644,
 112                 .proc_handler   = proc_dointvec_minmax,
 113                 .extra1         = &min_slot_table_size,
 114                 .extra2         = &max_slot_table_size
 115         },
 116         {
 117                 .procname       = "tcp_max_slot_table_entries",
 118                 .data           = &xprt_max_tcp_slot_table_entries,
 119                 .maxlen         = sizeof(unsigned int),
 120                 .mode           = 0644,
 121                 .proc_handler   = proc_dointvec_minmax,
 122                 .extra1         = &min_slot_table_size,
 123                 .extra2         = &max_tcp_slot_table_limit
 124         },
 125         {
 126                 .procname       = "min_resvport",
 127                 .data           = &xprt_min_resvport,
 128                 .maxlen         = sizeof(unsigned int),
 129                 .mode           = 0644,
 130                 .proc_handler   = proc_dointvec_minmax,
 131                 .extra1         = &xprt_min_resvport_limit,
 132                 .extra2         = &xprt_max_resvport_limit
 133         },
 134         {
 135                 .procname       = "max_resvport",
 136                 .data           = &xprt_max_resvport,
 137                 .maxlen         = sizeof(unsigned int),
 138                 .mode           = 0644,
 139                 .proc_handler   = proc_dointvec_minmax,
 140                 .extra1         = &xprt_min_resvport_limit,
 141                 .extra2         = &xprt_max_resvport_limit
 142         },
 143         {
 144                 .procname       = "tcp_fin_timeout",
 145                 .data           = &xs_tcp_fin_timeout,
 146                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 147                 .mode           = 0644,
 148                 .proc_handler   = proc_dointvec_jiffies,
 149         },
 150         { },
 151 };
 152
 153 static struct ctl_table sunrpc_table[] = {
 154         {
 155                 .procname       = "sunrpc",
 156                 .mode           = 0555,
 157                 .child          = xs_tunables_table
 158         },
 159         { },
 160 };
 161
 162 #endif
 163
 164 /*
 165  * Wait duration for a reply from the RPC portmapper.
 166  */
 167 #define XS_BIND_TO              (60U * HZ)
 168
 169 /*
 170  * Delay if a UDP socket connect error occurs.  This is most likely some
 171  * kind of resource problem on the local host.
 172  */
 173 #define XS_UDP_REEST_TO         (2U * HZ)
 174
 175 /*
 176  * The reestablish timeout allows clients to delay for a bit before attempting
 177  * to reconnect to a server that just dropped our connection.
 178  *
 179  * We implement an exponential backoff when trying to reestablish a TCP
 180  * transport connection with the server.  Some servers like to drop a TCP
 181  * connection when they are overworked, so we start with a short timeout and
 182  * increase over time if the server is down or not responding.
 183  */
 184 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 185
 186 /*
 187  * TCP idle timeout; client drops the transport socket if it is idle
 188  * for this long.  Note that we also timeout UDP sockets to prevent
 189  * holding port numbers when there is no RPC traffic.
 190  */
 191 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 192
 193 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 194 # undef  RPC_DEBUG_DATA
 195 # define RPCDBG_FACILITY        RPCDBG_TRANS
 196 #endif
 197
 198 #ifdef RPC_DEBUG_DATA
 199 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 200 {
 201         u8 *buf = (u8 *) packet;
 202         int j;
 203
 204         dprintk("RPC:       %s\n", msg);
 205         for (j = 0; j < count && j < 128; j += 4) {
 206                 if (!(j & 31)) {
 207                         if (j)
 208                                 dprintk("\n");
 209                         dprintk("0x%04x ", j);
 210                 }
 211                 dprintk("%02x%02x%02x%02x ",
 212                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 213         }
 214         dprintk("\n");
 215 }
 216 #else
 217 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 218 {
 219         /* NOP */
 220 }
 221 #endif
 222
 223 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 224 {
 225         return (struct rpc_xprt *) sk->sk_user_data;
 226 }
 227
 228 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 229 {
 230         return (struct sockaddr *) &xprt->addr;
 231 }
 232
 233 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 234 {
 235         return (struct sockaddr_un *) &xprt->addr;
 236 }
 237
 238 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 239 {
 240         return (struct sockaddr_in *) &xprt->addr;
 241 }
 242
 243 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 244 {
 245         return (struct sockaddr_in6 *) &xprt->addr;
 246 }
 247
 248 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 249 {
 250         struct sockaddr *sap = xs_addr(xprt);
 251         struct sockaddr_in6 *sin6;
 252         struct sockaddr_in *sin;
 253         struct sockaddr_un *sun;
 254         char buf[128];
 255
 256         switch (sap->sa_family) {
 257         case AF_LOCAL:
 258                 sun = xs_addr_un(xprt);
 259                 strlcpy(buf, sun->sun_path, sizeof(buf));
 260                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 261                                                 kstrdup(buf, GFP_KERNEL);
 262                 break;
 263         case AF_INET:
 264                 (void)rpc_ntop(sap, buf, sizeof(buf));
 265                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 266                                                 kstrdup(buf, GFP_KERNEL);
 267                 sin = xs_addr_in(xprt);
 268                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 269                 break;
 270         case AF_INET6:
 271                 (void)rpc_ntop(sap, buf, sizeof(buf));
 272                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 273                                                 kstrdup(buf, GFP_KERNEL);
 274                 sin6 = xs_addr_in6(xprt);
 275                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 276                 break;
 277         default:
 278                 BUG();
 279         }
 280
 281         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 282 }
 283
 284 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 285 {
 286         struct sockaddr *sap = xs_addr(xprt);
 287         char buf[128];
 288
 289         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 290         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 291
 292         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 293         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 294 }
 295
 296 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 297                                      const char *protocol,
 298                                      const char *netid)
 299 {
 300         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 301         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 302         xs_format_common_peer_addresses(xprt);
 303         xs_format_common_peer_ports(xprt);
 304 }
 305
 306 static void xs_update_peer_port(struct rpc_xprt *xprt)
 307 {
 308         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 309         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 310
 311         xs_format_common_peer_ports(xprt);
 312 }
 313
 314 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 315 {
 316         unsigned int i;
 317
 318         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 319                 switch (i) {
 320                 case RPC_DISPLAY_PROTO:
 321                 case RPC_DISPLAY_NETID:
 322                         continue;
 323                 default:
 324                         kfree(xprt->address_strings[i]);
 325                 }
 326 }
 327
 328 static size_t
 329 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 330 {
 331         size_t i,n;
 332
 333         if (!(buf->flags & XDRBUF_SPARSE_PAGES))
 334                 return want;
 335         if (want > buf->page_len)
 336                 want = buf->page_len;
 337         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 338         for (i = 0; i < n; i++) {
 339                 if (buf->pages[i])
 340                         continue;
 341                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 342                 if (!buf->pages[i]) {
 343                         buf->page_len = (i * PAGE_SIZE) - buf->page_base;
 344                         return buf->page_len;
 345                 }
 346         }
 347         return want;
 348 }
 349
 350 static ssize_t
 351 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 352 {
 353         ssize_t ret;
 354         if (seek != 0)
 355                 iov_iter_advance(&msg->msg_iter, seek);
 356         ret = sock_recvmsg(sock, msg, flags);
 357         return ret > 0 ? ret + seek : ret;
 358 }
 359
 360 static ssize_t
 361 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 362                 struct kvec *kvec, size_t count, size_t seek)
 363 {
 364         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 365         return xs_sock_recvmsg(sock, msg, flags, seek);
 366 }
 367
 368 static ssize_t
 369 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 370                 struct bio_vec *bvec, unsigned long nr, size_t count,
 371                 size_t seek)
 372 {
 373         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 374         return xs_sock_recvmsg(sock, msg, flags, seek);
 375 }
 376
 377 static ssize_t
 378 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 379                 size_t count)
 380 {
 381         struct kvec kvec = { 0 };
 382         return xs_read_kvec(sock, msg, flags | MSG_TRUNC, &kvec, count, 0);
 383 }
 384
 385 static ssize_t
 386 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 387                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 388 {
 389         size_t want, seek_init = seek, offset = 0;
 390         ssize_t ret;
 391
 392         if (seek < buf->head[0].iov_len) {
 393                 want = min_t(size_t, count, buf->head[0].iov_len);
 394                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 395                 if (ret <= 0)
 396                         goto sock_err;
 397                 offset += ret;
 398                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 399                         goto out;
 400                 if (ret != want)
 401                         goto eagain;
 402                 seek = 0;
 403         } else {
 404                 seek -= buf->head[0].iov_len;
 405                 offset += buf->head[0].iov_len;
 406         }
 407         if (seek < buf->page_len) {
 408                 want = xs_alloc_sparse_pages(buf,
 409                                 min_t(size_t, count - offset, buf->page_len),
 410                                 GFP_NOWAIT);
 411                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 412                                 xdr_buf_pagecount(buf),
 413                                 want + buf->page_base,
 414                                 seek + buf->page_base);
 415                 if (ret <= 0)
 416                         goto sock_err;
 417                 offset += ret - buf->page_base;
 418                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 419                         goto out;
 420                 if (ret != want)
 421                         goto eagain;
 422                 seek = 0;
 423         } else {
 424                 seek -= buf->page_len;
 425                 offset += buf->page_len;
 426         }
 427         if (seek < buf->tail[0].iov_len) {
 428                 want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 429                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 430                 if (ret <= 0)
 431                         goto sock_err;
 432                 offset += ret;
 433                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 434                         goto out;
 435                 if (ret != want)
 436                         goto eagain;
 437         } else
 438                 offset += buf->tail[0].iov_len;
 439         ret = -EMSGSIZE;
 440         msg->msg_flags |= MSG_TRUNC;
 441 out:
 442         *read = offset - seek_init;
 443         return ret;
 444 eagain:
 445         ret = -EAGAIN;
 446         goto out;
 447 sock_err:
 448         offset += seek;
 449         goto out;
 450 }
 451
 452 static void
 453 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 454 {
 455         if (!transport->recv.copied) {
 456                 if (buf->head[0].iov_len >= transport->recv.offset)
 457                         memcpy(buf->head[0].iov_base,
 458                                         &transport->recv.xid,
 459                                         transport->recv.offset);
 460                 transport->recv.copied = transport->recv.offset;
 461         }
 462 }
 463
 464 static bool
 465 xs_read_stream_request_done(struct sock_xprt *transport)
 466 {
 467         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 468 }
 469
 470 static ssize_t
 471 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 472                 int flags, struct rpc_rqst *req)
 473 {
 474         struct xdr_buf *buf = &req->rq_private_buf;
 475         size_t want, read;
 476         ssize_t ret;
 477
 478         xs_read_header(transport, buf);
 479
 480         want = transport->recv.len - transport->recv.offset;
 481         ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 482                         transport->recv.copied + want, transport->recv.copied,
 483                         &read);
 484         transport->recv.offset += read;
 485         transport->recv.copied += read;
 486         if (transport->recv.offset == transport->recv.len) {
 487                 if (xs_read_stream_request_done(transport))
 488                         msg->msg_flags |= MSG_EOR;
 489                 return transport->recv.copied;
 490         }
 491
 492         switch (ret) {
 493         case -EMSGSIZE:
 494                 return transport->recv.copied;
 495         case 0:
 496                 return -ESHUTDOWN;
 497         default:
 498                 if (ret < 0)
 499                         return ret;
 500         }
 501         return -EAGAIN;
 502 }
 503
 504 static size_t
 505 xs_read_stream_headersize(bool isfrag)
 506 {
 507         if (isfrag)
 508                 return sizeof(__be32);
 509         return 3 * sizeof(__be32);
 510 }
 511
 512 static ssize_t
 513 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 514                 int flags, size_t want, size_t seek)
 515 {
 516         struct kvec kvec = {
 517                 .iov_base = &transport->recv.fraghdr,
 518                 .iov_len = want,
 519         };
 520         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 521 }
 522
 523 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 524 static ssize_t
 525 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 526 {
 527         struct rpc_xprt *xprt = &transport->xprt;
 528         struct rpc_rqst *req;
 529         ssize_t ret;
 530
 531         /* Look up and lock the request corresponding to the given XID */
 532         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 533         if (!req) {
 534                 printk(KERN_WARNING "Callback slot table overflowed\n");
 535                 return -ESHUTDOWN;
 536         }
 537
 538         ret = xs_read_stream_request(transport, msg, flags, req);
 539         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 540                 xprt_complete_bc_request(req, ret);
 541
 542         return ret;
 543 }
 544 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 545 static ssize_t
 546 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 547 {
 548         return -ESHUTDOWN;
 549 }
 550 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 551
 552 static ssize_t
 553 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 554 {
 555         struct rpc_xprt *xprt = &transport->xprt;
 556         struct rpc_rqst *req;
 557         ssize_t ret = 0;
 558
 559         /* Look up and lock the request corresponding to the given XID */
 560         spin_lock(&xprt->queue_lock);
 561         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 562         if (!req) {
 563                 msg->msg_flags |= MSG_TRUNC;
 564                 goto out;
 565         }
 566         xprt_pin_rqst(req);
 567         spin_unlock(&xprt->queue_lock);
 568
 569         ret = xs_read_stream_request(transport, msg, flags, req);
 570
 571         spin_lock(&xprt->queue_lock);
 572         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 573                 xprt_complete_rqst(req->rq_task, ret);
 574         xprt_unpin_rqst(req);
 575 out:
 576         spin_unlock(&xprt->queue_lock);
 577         return ret;
 578 }
 579
 580 static ssize_t
 581 xs_read_stream(struct sock_xprt *transport, int flags)
 582 {
 583         struct msghdr msg = { 0 };
 584         size_t want, read = 0;
 585         ssize_t ret = 0;
 586
 587         if (transport->recv.len == 0) {
 588                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 589                 ret = xs_read_stream_header(transport, &msg, flags, want,
 590                                 transport->recv.offset);
 591                 if (ret <= 0)
 592                         goto out_err;
 593                 transport->recv.offset = ret;
 594                 if (ret != want) {
 595                         ret = -EAGAIN;
 596                         goto out_err;
 597                 }
 598                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 599                         RPC_FRAGMENT_SIZE_MASK;
 600                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 601                 read = ret;
 602         }
 603
 604         switch (be32_to_cpu(transport->recv.calldir)) {
 605         case RPC_CALL:
 606                 ret = xs_read_stream_call(transport, &msg, flags);
 607                 break;
 608         case RPC_REPLY:
 609                 ret = xs_read_stream_reply(transport, &msg, flags);
 610         }
 611         if (msg.msg_flags & MSG_TRUNC) {
 612                 transport->recv.calldir = cpu_to_be32(-1);
 613                 transport->recv.copied = -1;
 614         }
 615         if (ret < 0)
 616                 goto out_err;
 617         read += ret;
 618         if (transport->recv.offset < transport->recv.len) {
 619                 ret = xs_read_discard(transport->sock, &msg, flags,
 620                                 transport->recv.len - transport->recv.offset);
 621                 if (ret <= 0)
 622                         goto out_err;
 623                 transport->recv.offset += ret;
 624                 read += ret;
 625                 if (transport->recv.offset != transport->recv.len)
 626                         return -EAGAIN;
 627         }
 628         if (xs_read_stream_request_done(transport)) {
 629                 trace_xs_stream_read_request(transport);
 630                 transport->recv.copied = 0;
 631         }
 632         transport->recv.offset = 0;
 633         transport->recv.len = 0;
 634         return read;
 635 out_err:
 636         switch (ret) {
 637         case 0:
 638         case -ESHUTDOWN:
 639                 xprt_force_disconnect(&transport->xprt);
 640                 return -ESHUTDOWN;
 641         }
 642         return ret;
 643 }
 644
 645 static void xs_stream_data_receive(struct sock_xprt *transport)
 646 {
 647         size_t read = 0;
 648         ssize_t ret = 0;
 649
 650         mutex_lock(&transport->recv_mutex);
 651         if (transport->sock == NULL)
 652                 goto out;
 653         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 654         for (;;) {
 655                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 656                 if (ret <= 0)
 657                         break;
 658                 read += ret;
 659                 cond_resched();
 660         }
 661 out:
 662         mutex_unlock(&transport->recv_mutex);
 663         trace_xs_stream_read_data(&transport->xprt, ret, read);
 664 }
 665
 666 static void xs_stream_data_receive_workfn(struct work_struct *work)
 667 {
 668         struct sock_xprt *transport =
 669                 container_of(work, struct sock_xprt, recv_worker);
 670         xs_stream_data_receive(transport);
 671 }
 672
 673 static void
 674 xs_stream_reset_connect(struct sock_xprt *transport)
 675 {
 676         transport->recv.offset = 0;
 677         transport->recv.len = 0;
 678         transport->recv.copied = 0;
 679         transport->xmit.offset = 0;
 680         transport->xprt.stat.connect_count++;
 681         transport->xprt.stat.connect_start = jiffies;
 682 }
 683
 684 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 685
 686 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 687 {
 688         struct msghdr msg = {
 689                 .msg_name       = addr,
 690                 .msg_namelen    = addrlen,
 691                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 692         };
 693         struct kvec iov = {
 694                 .iov_base       = vec->iov_base + base,
 695                 .iov_len        = vec->iov_len - base,
 696         };
 697
 698         if (iov.iov_len != 0)
 699                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 700         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 701 }
 702
 703 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p)
 704 {
 705         ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 706                         int offset, size_t size, int flags);
 707         struct page **ppage;
 708         unsigned int remainder;
 709         int err;
 710
 711         remainder = xdr->page_len - base;
 712         base += xdr->page_base;
 713         ppage = xdr->pages + (base >> PAGE_SHIFT);
 714         base &= ~PAGE_MASK;
 715         do_sendpage = sock->ops->sendpage;
 716         if (!zerocopy)
 717                 do_sendpage = sock_no_sendpage;
 718         for(;;) {
 719                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 720                 int flags = XS_SENDMSG_FLAGS;
 721
 722                 remainder -= len;
 723                 if (more)
 724                         flags |= MSG_MORE;
 725                 if (remainder != 0)
 726                         flags |= MSG_SENDPAGE_NOTLAST | MSG_MORE;
 727                 err = do_sendpage(sock, *ppage, base, len, flags);
 728                 if (remainder == 0 || err != len)
 729                         break;
 730                 *sent_p += err;
 731                 ppage++;
 732                 base = 0;
 733         }
 734         if (err > 0) {
 735                 *sent_p += err;
 736                 err = 0;
 737         }
 738         return err;
 739 }
 740
 741 /**
 742  * xs_sendpages - write pages directly to a socket
 743  * @sock: socket to send on
 744  * @addr: UDP only -- address of destination
 745  * @addrlen: UDP only -- length of destination address
 746  * @xdr: buffer containing this request
 747  * @base: starting position in the buffer
 748  * @zerocopy: true if it is safe to use sendpage()
 749  * @sent_p: return the total number of bytes successfully queued for sending
 750  *
 751  */
 752 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 753 {
 754         unsigned int remainder = xdr->len - base;
 755         int err = 0;
 756         int sent = 0;
 757
 758         if (unlikely(!sock))
 759                 return -ENOTSOCK;
 760
 761         if (base != 0) {
 762                 addr = NULL;
 763                 addrlen = 0;
 764         }
 765
 766         if (base < xdr->head[0].iov_len || addr != NULL) {
 767                 unsigned int len = xdr->head[0].iov_len - base;
 768                 remainder -= len;
 769                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 770                 if (remainder == 0 || err != len)
 771                         goto out;
 772                 *sent_p += err;
 773                 base = 0;
 774         } else
 775                 base -= xdr->head[0].iov_len;
 776
 777         if (base < xdr->page_len) {
 778                 unsigned int len = xdr->page_len - base;
 779                 remainder -= len;
 780                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 781                 *sent_p += sent;
 782                 if (remainder == 0 || sent != len)
 783                         goto out;
 784                 base = 0;
 785         } else
 786                 base -= xdr->page_len;
 787
 788         if (base >= xdr->tail[0].iov_len)
 789                 return 0;
 790         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 791 out:
 792         if (err > 0) {
 793                 *sent_p += err;
 794                 err = 0;
 795         }
 796         return err;
 797 }
 798
 799 /**
 800  * xs_nospace - handle transmit was incomplete
 801  * @req: pointer to RPC request
 802  *
 803  */
 804 static int xs_nospace(struct rpc_rqst *req)
 805 {
 806         struct rpc_xprt *xprt = req->rq_xprt;
 807         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 808         struct sock *sk = transport->inet;
 809         int ret = -EAGAIN;
 810
 811         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 812                         req->rq_task->tk_pid,
 813                         req->rq_slen - transport->xmit.offset,
 814                         req->rq_slen);
 815
 816         /* Protect against races with write_space */
 817         spin_lock_bh(&xprt->transport_lock);
 818
 819         /* Don't race with disconnect */
 820         if (xprt_connected(xprt)) {
 821                 /* wait for more buffer space */
 822                 sk->sk_write_pending++;
 823                 xprt_wait_for_buffer_space(xprt);
 824         } else
 825                 ret = -ENOTCONN;
 826
 827         spin_unlock_bh(&xprt->transport_lock);
 828
 829         /* Race breaker in case memory is freed before above code is called */
 830         if (ret == -EAGAIN) {
 831                 struct socket_wq *wq;
 832
 833                 rcu_read_lock();
 834                 wq = rcu_dereference(sk->sk_wq);
 835                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 836                 rcu_read_unlock();
 837
 838                 sk->sk_write_space(sk);
 839         }
 840         return ret;
 841 }
 842
 843 static void
 844 xs_stream_prepare_request(struct rpc_rqst *req)
 845 {
 846         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_NOIO);
 847 }
 848
 849 /*
 850  * Determine if the previous message in the stream was aborted before it
 851  * could complete transmission.
 852  */
 853 static bool
 854 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 855 {
 856         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 857 }
 858
 859 /*
 860  * Construct a stream transport record marker in @buf.
 861  */
 862 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 863 {
 864         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 865         rpc_fraghdr *base = buf->head[0].iov_base;
 866         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 867 }
 868
 869 /**
 870  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 871  * @req: pointer to RPC request
 872  *
 873  * Return values:
 874  *        0:    The request has been sent
 875  *   EAGAIN:    The socket was blocked, please call again later to
 876  *              complete the request
 877  * ENOTCONN:    Caller needs to invoke connect logic then call again
 878  *    other:    Some other error occured, the request was not sent
 879  */
 880 static int xs_local_send_request(struct rpc_rqst *req)
 881 {
 882         struct rpc_xprt *xprt = req->rq_xprt;
 883         struct sock_xprt *transport =
 884                                 container_of(xprt, struct sock_xprt, xprt);
 885         struct xdr_buf *xdr = &req->rq_snd_buf;
 886         int status;
 887         int sent = 0;
 888
 889         /* Close the stream if the previous transmission was incomplete */
 890         if (xs_send_request_was_aborted(transport, req)) {
 891                 xs_close(xprt);
 892                 return -ENOTCONN;
 893         }
 894
 895         xs_encode_stream_record_marker(&req->rq_snd_buf);
 896
 897         xs_pktdump("packet data:",
 898                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 899
 900         req->rq_xtime = ktime_get();
 901         status = xs_sendpages(transport->sock, NULL, 0, xdr,
 902                               transport->xmit.offset,
 903                               true, &sent);
 904         dprintk("RPC:       %s(%u) = %d\n",
 905                         __func__, xdr->len - transport->xmit.offset, status);
 906
 907         if (status == -EAGAIN && sock_writeable(transport->inet))
 908                 status = -ENOBUFS;
 909
 910         if (likely(sent > 0) || status == 0) {
 911                 transport->xmit.offset += sent;
 912                 req->rq_bytes_sent = transport->xmit.offset;
 913                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 914                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 915                         req->rq_bytes_sent = 0;
 916                         transport->xmit.offset = 0;
 917                         return 0;
 918                 }
 919                 status = -EAGAIN;
 920         }
 921
 922         switch (status) {
 923         case -ENOBUFS:
 924                 break;
 925         case -EAGAIN:
 926                 status = xs_nospace(req);
 927                 break;
 928         default:
 929                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 930                         -status);
 931                 /* fall through */
 932         case -EPIPE:
 933                 xs_close(xprt);
 934                 status = -ENOTCONN;
 935         }
 936
 937         return status;
 938 }
 939
 940 /**
 941  * xs_udp_send_request - write an RPC request to a UDP socket
 942  * @req: pointer to RPC request
 943  *
 944  * Return values:
 945  *        0:    The request has been sent
 946  *   EAGAIN:    The socket was blocked, please call again later to
 947  *              complete the request
 948  * ENOTCONN:    Caller needs to invoke connect logic then call again
 949  *    other:    Some other error occurred, the request was not sent
 950  */
 951 static int xs_udp_send_request(struct rpc_rqst *req)
 952 {
 953         struct rpc_xprt *xprt = req->rq_xprt;
 954         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 955         struct xdr_buf *xdr = &req->rq_snd_buf;
 956         int sent = 0;
 957         int status;
 958
 959         xs_pktdump("packet data:",
 960                                 req->rq_svec->iov_base,
 961                                 req->rq_svec->iov_len);
 962
 963         if (!xprt_bound(xprt))
 964                 return -ENOTCONN;
 965
 966         if (!xprt_request_get_cong(xprt, req))
 967                 return -EBADSLT;
 968
 969         req->rq_xtime = ktime_get();
 970         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 971                               xdr, 0, true, &sent);
 972
 973         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 974                         xdr->len, status);
 975
 976         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 977         if (status == -EPERM)
 978                 goto process_status;
 979
 980         if (status == -EAGAIN && sock_writeable(transport->inet))
 981                 status = -ENOBUFS;
 982
 983         if (sent > 0 || status == 0) {
 984                 req->rq_xmit_bytes_sent += sent;
 985                 if (sent >= req->rq_slen)
 986                         return 0;
 987                 /* Still some bytes left; set up for a retry later. */
 988                 status = -EAGAIN;
 989         }
 990
 991 process_status:
 992         switch (status) {
 993         case -ENOTSOCK:
 994                 status = -ENOTCONN;
 995                 /* Should we call xs_close() here? */
 996                 break;
 997         case -EAGAIN:
 998                 status = xs_nospace(req);
 999                 break;
1000         case -ENETUNREACH:
1001         case -ENOBUFS:
1002         case -EPIPE:
1003         case -ECONNREFUSED:
1004         case -EPERM:
1005                 /* When the server has died, an ICMP port unreachable message
1006                  * prompts ECONNREFUSED. */
1007                 break;
1008         default:
1009                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1010                         -status);
1011         }
1012
1013         return status;
1014 }
1015
1016 /**
1017  * xs_tcp_send_request - write an RPC request to a TCP socket
1018  * @req: pointer to RPC request
1019  *
1020  * Return values:
1021  *        0:    The request has been sent
1022  *   EAGAIN:    The socket was blocked, please call again later to
1023  *              complete the request
1024  * ENOTCONN:    Caller needs to invoke connect logic then call again
1025  *    other:    Some other error occurred, the request was not sent
1026  *
1027  * XXX: In the case of soft timeouts, should we eventually give up
1028  *      if sendmsg is not able to make progress?
1029  */
1030 static int xs_tcp_send_request(struct rpc_rqst *req)
1031 {
1032         struct rpc_xprt *xprt = req->rq_xprt;
1033         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1034         struct xdr_buf *xdr = &req->rq_snd_buf;
1035         bool zerocopy = true;
1036         bool vm_wait = false;
1037         int status;
1038         int sent;
1039
1040         /* Close the stream if the previous transmission was incomplete */
1041         if (xs_send_request_was_aborted(transport, req)) {
1042                 if (transport->sock != NULL)
1043                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1044                 return -ENOTCONN;
1045         }
1046
1047         xs_encode_stream_record_marker(&req->rq_snd_buf);
1048
1049         xs_pktdump("packet data:",
1050                                 req->rq_svec->iov_base,
1051                                 req->rq_svec->iov_len);
1052         /* Don't use zero copy if this is a resend. If the RPC call
1053          * completes while the socket holds a reference to the pages,
1054          * then we may end up resending corrupted data.
1055          */
1056         if (req->rq_task->tk_flags & RPC_TASK_SENT)
1057                 zerocopy = false;
1058
1059         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1060                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1061
1062         /* Continue transmitting the packet/record. We must be careful
1063          * to cope with writespace callbacks arriving _after_ we have
1064          * called sendmsg(). */
1065         req->rq_xtime = ktime_get();
1066         while (1) {
1067                 sent = 0;
1068                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1069                                       transport->xmit.offset,
1070                                       zerocopy, &sent);
1071
1072                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1073                                 xdr->len - transport->xmit.offset, status);
1074
1075                 /* If we've sent the entire packet, immediately
1076                  * reset the count of bytes sent. */
1077                 transport->xmit.offset += sent;
1078                 req->rq_bytes_sent = transport->xmit.offset;
1079                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
1080                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1081                         req->rq_bytes_sent = 0;
1082                         transport->xmit.offset = 0;
1083                         return 0;
1084                 }
1085
1086                 WARN_ON_ONCE(sent == 0 && status == 0);
1087
1088                 if (status == -EAGAIN ) {
1089                         /*
1090                          * Return EAGAIN if we're sure we're hitting the
1091                          * socket send buffer limits.
1092                          */
1093                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1094                                 break;
1095                         /*
1096                          * Did we hit a memory allocation failure?
1097                          */
1098                         if (sent == 0) {
1099                                 status = -ENOBUFS;
1100                                 if (vm_wait)
1101                                         break;
1102                                 /* Retry, knowing now that we're below the
1103                                  * socket send buffer limit
1104                                  */
1105                                 vm_wait = true;
1106                         }
1107                         continue;
1108                 }
1109                 if (status < 0)
1110                         break;
1111                 vm_wait = false;
1112         }
1113
1114         switch (status) {
1115         case -ENOTSOCK:
1116                 status = -ENOTCONN;
1117                 /* Should we call xs_close() here? */
1118                 break;
1119         case -EAGAIN:
1120                 status = xs_nospace(req);
1121                 break;
1122         case -ECONNRESET:
1123         case -ECONNREFUSED:
1124         case -ENOTCONN:
1125         case -EADDRINUSE:
1126         case -ENOBUFS:
1127         case -EPIPE:
1128                 break;
1129         default:
1130                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1131                         -status);
1132         }
1133
1134         return status;
1135 }
1136
1137 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1138 {
1139         transport->old_data_ready = sk->sk_data_ready;
1140         transport->old_state_change = sk->sk_state_change;
1141         transport->old_write_space = sk->sk_write_space;
1142         transport->old_error_report = sk->sk_error_report;
1143 }
1144
1145 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1146 {
1147         sk->sk_data_ready = transport->old_data_ready;
1148         sk->sk_state_change = transport->old_state_change;
1149         sk->sk_write_space = transport->old_write_space;
1150         sk->sk_error_report = transport->old_error_report;
1151 }
1152
1153 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1154 {
1155         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1156
1157         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1158 }
1159
1160 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1161 {
1162         smp_mb__before_atomic();
1163         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1164         clear_bit(XPRT_CLOSING, &xprt->state);
1165         xs_sock_reset_state_flags(xprt);
1166         smp_mb__after_atomic();
1167 }
1168
1169 /**
1170  * xs_error_report - callback to handle TCP socket state errors
1171  * @sk: socket
1172  *
1173  * Note: we don't call sock_error() since there may be a rpc_task
1174  * using the socket, and so we don't want to clear sk->sk_err.
1175  */
1176 static void xs_error_report(struct sock *sk)
1177 {
1178         struct rpc_xprt *xprt;
1179         int err;
1180
1181         read_lock_bh(&sk->sk_callback_lock);
1182         if (!(xprt = xprt_from_sock(sk)))
1183                 goto out;
1184
1185         err = -sk->sk_err;
1186         if (err == 0)
1187                 goto out;
1188         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1189                         xprt, -err);
1190         trace_rpc_socket_error(xprt, sk->sk_socket, err);
1191         xprt_wake_pending_tasks(xprt, err);
1192  out:
1193         read_unlock_bh(&sk->sk_callback_lock);
1194 }
1195
1196 static void xs_reset_transport(struct sock_xprt *transport)
1197 {
1198         struct socket *sock = transport->sock;
1199         struct sock *sk = transport->inet;
1200         struct rpc_xprt *xprt = &transport->xprt;
1201
1202         if (sk == NULL)
1203                 return;
1204
1205         if (atomic_read(&transport->xprt.swapper))
1206                 sk_clear_memalloc(sk);
1207
1208         kernel_sock_shutdown(sock, SHUT_RDWR);
1209
1210         mutex_lock(&transport->recv_mutex);
1211         write_lock_bh(&sk->sk_callback_lock);
1212         transport->inet = NULL;
1213         transport->sock = NULL;
1214
1215         sk->sk_user_data = NULL;
1216
1217         xs_restore_old_callbacks(transport, sk);
1218         xprt_clear_connected(xprt);
1219         write_unlock_bh(&sk->sk_callback_lock);
1220         xs_sock_reset_connection_flags(xprt);
1221         mutex_unlock(&transport->recv_mutex);
1222
1223         trace_rpc_socket_close(xprt, sock);
1224         sock_release(sock);
1225 }
1226
1227 /**
1228  * xs_close - close a socket
1229  * @xprt: transport
1230  *
1231  * This is used when all requests are complete; ie, no DRC state remains
1232  * on the server we want to save.
1233  *
1234  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1235  * xs_reset_transport() zeroing the socket from underneath a writer.
1236  */
1237 static void xs_close(struct rpc_xprt *xprt)
1238 {
1239         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1240
1241         dprintk("RPC:       xs_close xprt %p\n", xprt);
1242
1243         xs_reset_transport(transport);
1244         xprt->reestablish_timeout = 0;
1245
1246         xprt_disconnect_done(xprt);
1247 }
1248
1249 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1250 {
1251         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1252                 xprt);
1253         xprt_disconnect_done(xprt);
1254 }
1255
1256 static void xs_xprt_free(struct rpc_xprt *xprt)
1257 {
1258         xs_free_peer_addresses(xprt);
1259         xprt_free(xprt);
1260 }
1261
1262 /**
1263  * xs_destroy - prepare to shutdown a transport
1264  * @xprt: doomed transport
1265  *
1266  */
1267 static void xs_destroy(struct rpc_xprt *xprt)
1268 {
1269         struct sock_xprt *transport = container_of(xprt,
1270                         struct sock_xprt, xprt);
1271         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1272
1273         cancel_delayed_work_sync(&transport->connect_worker);
1274         xs_close(xprt);
1275         cancel_work_sync(&transport->recv_worker);
1276         xs_xprt_free(xprt);
1277         module_put(THIS_MODULE);
1278 }
1279
1280 /**
1281  * xs_udp_data_read_skb - receive callback for UDP sockets
1282  * @xprt: transport
1283  * @sk: socket
1284  * @skb: skbuff
1285  *
1286  */
1287 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1288                 struct sock *sk,
1289                 struct sk_buff *skb)
1290 {
1291         struct rpc_task *task;
1292         struct rpc_rqst *rovr;
1293         int repsize, copied;
1294         u32 _xid;
1295         __be32 *xp;
1296
1297         repsize = skb->len;
1298         if (repsize < 4) {
1299                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1300                 return;
1301         }
1302
1303         /* Copy the XID from the skb... */
1304         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1305         if (xp == NULL)
1306                 return;
1307
1308         /* Look up and lock the request corresponding to the given XID */
1309         spin_lock(&xprt->queue_lock);
1310         rovr = xprt_lookup_rqst(xprt, *xp);
1311         if (!rovr)
1312                 goto out_unlock;
1313         xprt_pin_rqst(rovr);
1314         xprt_update_rtt(rovr->rq_task);
1315         spin_unlock(&xprt->queue_lock);
1316         task = rovr->rq_task;
1317
1318         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1319                 copied = repsize;
1320
1321         /* Suck it into the iovec, verify checksum if not done by hw. */
1322         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1323                 spin_lock(&xprt->queue_lock);
1324                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1325                 goto out_unpin;
1326         }
1327
1328
1329         spin_lock_bh(&xprt->transport_lock);
1330         xprt_adjust_cwnd(xprt, task, copied);
1331         spin_unlock_bh(&xprt->transport_lock);
1332         spin_lock(&xprt->queue_lock);
1333         xprt_complete_rqst(task, copied);
1334         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1335 out_unpin:
1336         xprt_unpin_rqst(rovr);
1337  out_unlock:
1338         spin_unlock(&xprt->queue_lock);
1339 }
1340
1341 static void xs_udp_data_receive(struct sock_xprt *transport)
1342 {
1343         struct sk_buff *skb;
1344         struct sock *sk;
1345         int err;
1346
1347         mutex_lock(&transport->recv_mutex);
1348         sk = transport->inet;
1349         if (sk == NULL)
1350                 goto out;
1351         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1352         for (;;) {
1353                 skb = skb_recv_udp(sk, 0, 1, &err);
1354                 if (skb == NULL)
1355                         break;
1356                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1357                 consume_skb(skb);
1358                 cond_resched();
1359         }
1360 out:
1361         mutex_unlock(&transport->recv_mutex);
1362 }
1363
1364 static void xs_udp_data_receive_workfn(struct work_struct *work)
1365 {
1366         struct sock_xprt *transport =
1367                 container_of(work, struct sock_xprt, recv_worker);
1368         xs_udp_data_receive(transport);
1369 }
1370
1371 /**
1372  * xs_data_ready - "data ready" callback for UDP sockets
1373  * @sk: socket with data to read
1374  *
1375  */
1376 static void xs_data_ready(struct sock *sk)
1377 {
1378         struct rpc_xprt *xprt;
1379
1380         read_lock_bh(&sk->sk_callback_lock);
1381         dprintk("RPC:       xs_data_ready...\n");
1382         xprt = xprt_from_sock(sk);
1383         if (xprt != NULL) {
1384                 struct sock_xprt *transport = container_of(xprt,
1385                                 struct sock_xprt, xprt);
1386                 transport->old_data_ready(sk);
1387                 /* Any data means we had a useful conversation, so
1388                  * then we don't need to delay the next reconnect
1389                  */
1390                 if (xprt->reestablish_timeout)
1391                         xprt->reestablish_timeout = 0;
1392                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1393                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1394         }
1395         read_unlock_bh(&sk->sk_callback_lock);
1396 }
1397
1398 /*
1399  * Helper function to force a TCP close if the server is sending
1400  * junk and/or it has put us in CLOSE_WAIT
1401  */
1402 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1403 {
1404         xprt_force_disconnect(xprt);
1405 }
1406
1407 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1408 static int xs_tcp_bc_up(struct svc_serv *serv, struct net *net)
1409 {
1410         int ret;
1411
1412         ret = svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
1413                               SVC_SOCK_ANONYMOUS);
1414         if (ret < 0)
1415                 return ret;
1416         return 0;
1417 }
1418
1419 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1420 {
1421         return PAGE_SIZE;
1422 }
1423 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1424
1425 /**
1426  * xs_tcp_state_change - callback to handle TCP socket state changes
1427  * @sk: socket whose state has changed
1428  *
1429  */
1430 static void xs_tcp_state_change(struct sock *sk)
1431 {
1432         struct rpc_xprt *xprt;
1433         struct sock_xprt *transport;
1434
1435         read_lock_bh(&sk->sk_callback_lock);
1436         if (!(xprt = xprt_from_sock(sk)))
1437                 goto out;
1438         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1439         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1440                         sk->sk_state, xprt_connected(xprt),
1441                         sock_flag(sk, SOCK_DEAD),
1442                         sock_flag(sk, SOCK_ZAPPED),
1443                         sk->sk_shutdown);
1444
1445         transport = container_of(xprt, struct sock_xprt, xprt);
1446         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1447         switch (sk->sk_state) {
1448         case TCP_ESTABLISHED:
1449                 spin_lock(&xprt->transport_lock);
1450                 if (!xprt_test_and_set_connected(xprt)) {
1451                         xprt->connect_cookie++;
1452                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1453                         xprt_clear_connecting(xprt);
1454
1455                         xprt->stat.connect_count++;
1456                         xprt->stat.connect_time += (long)jiffies -
1457                                                    xprt->stat.connect_start;
1458                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1459                 }
1460                 spin_unlock(&xprt->transport_lock);
1461                 break;
1462         case TCP_FIN_WAIT1:
1463                 /* The client initiated a shutdown of the socket */
1464                 xprt->connect_cookie++;
1465                 xprt->reestablish_timeout = 0;
1466                 set_bit(XPRT_CLOSING, &xprt->state);
1467                 smp_mb__before_atomic();
1468                 clear_bit(XPRT_CONNECTED, &xprt->state);
1469                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1470                 smp_mb__after_atomic();
1471                 break;
1472         case TCP_CLOSE_WAIT:
1473                 /* The server initiated a shutdown of the socket */
1474                 xprt->connect_cookie++;
1475                 clear_bit(XPRT_CONNECTED, &xprt->state);
1476                 xs_tcp_force_close(xprt);
1477                 /* fall through */
1478         case TCP_CLOSING:
1479                 /*
1480                  * If the server closed down the connection, make sure that
1481                  * we back off before reconnecting
1482                  */
1483                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1484                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1485                 break;
1486         case TCP_LAST_ACK:
1487                 set_bit(XPRT_CLOSING, &xprt->state);
1488                 smp_mb__before_atomic();
1489                 clear_bit(XPRT_CONNECTED, &xprt->state);
1490                 smp_mb__after_atomic();
1491                 break;
1492         case TCP_CLOSE:
1493                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1494                                         &transport->sock_state))
1495                         xprt_clear_connecting(xprt);
1496                 clear_bit(XPRT_CLOSING, &xprt->state);
1497                 if (sk->sk_err)
1498                         xprt_wake_pending_tasks(xprt, -sk->sk_err);
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  * @task: task that timed out
1611  *
1612  * Adjust the congestion window after a retransmit timeout has occurred.
1613  */
1614 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1615 {
1616         spin_lock_bh(&xprt->transport_lock);
1617         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1618         spin_unlock_bh(&xprt->transport_lock);
1619 }
1620
1621 static int xs_get_random_port(void)
1622 {
1623         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1624         unsigned short range;
1625         unsigned short rand;
1626
1627         if (max < min)
1628                 return -EADDRINUSE;
1629         range = max - min + 1;
1630         rand = (unsigned short) prandom_u32() % range;
1631         return rand + min;
1632 }
1633
1634 /**
1635  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1636  * @sock: socket
1637  *
1638  * Note that this function has to be called on all sockets that share the
1639  * same port, and it must be called before binding.
1640  */
1641 static void xs_sock_set_reuseport(struct socket *sock)
1642 {
1643         int opt = 1;
1644
1645         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1646                         (char *)&opt, sizeof(opt));
1647 }
1648
1649 static unsigned short xs_sock_getport(struct socket *sock)
1650 {
1651         struct sockaddr_storage buf;
1652         unsigned short port = 0;
1653
1654         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1655                 goto out;
1656         switch (buf.ss_family) {
1657         case AF_INET6:
1658                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1659                 break;
1660         case AF_INET:
1661                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1662         }
1663 out:
1664         return port;
1665 }
1666
1667 /**
1668  * xs_set_port - reset the port number in the remote endpoint address
1669  * @xprt: generic transport
1670  * @port: new port number
1671  *
1672  */
1673 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1674 {
1675         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1676
1677         rpc_set_port(xs_addr(xprt), port);
1678         xs_update_peer_port(xprt);
1679 }
1680
1681 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1682 {
1683         if (transport->srcport == 0)
1684                 transport->srcport = xs_sock_getport(sock);
1685 }
1686
1687 static int xs_get_srcport(struct sock_xprt *transport)
1688 {
1689         int port = transport->srcport;
1690
1691         if (port == 0 && transport->xprt.resvport)
1692                 port = xs_get_random_port();
1693         return port;
1694 }
1695
1696 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1697 {
1698         if (transport->srcport != 0)
1699                 transport->srcport = 0;
1700         if (!transport->xprt.resvport)
1701                 return 0;
1702         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1703                 return xprt_max_resvport;
1704         return --port;
1705 }
1706 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1707 {
1708         struct sockaddr_storage myaddr;
1709         int err, nloop = 0;
1710         int port = xs_get_srcport(transport);
1711         unsigned short last;
1712
1713         /*
1714          * If we are asking for any ephemeral port (i.e. port == 0 &&
1715          * transport->xprt.resvport == 0), don't bind.  Let the local
1716          * port selection happen implicitly when the socket is used
1717          * (for example at connect time).
1718          *
1719          * This ensures that we can continue to establish TCP
1720          * connections even when all local ephemeral ports are already
1721          * a part of some TCP connection.  This makes no difference
1722          * for UDP sockets, but also doens't harm them.
1723          *
1724          * If we're asking for any reserved port (i.e. port == 0 &&
1725          * transport->xprt.resvport == 1) xs_get_srcport above will
1726          * ensure that port is non-zero and we will bind as needed.
1727          */
1728         if (port <= 0)
1729                 return port;
1730
1731         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1732         do {
1733                 rpc_set_port((struct sockaddr *)&myaddr, port);
1734                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1735                                 transport->xprt.addrlen);
1736                 if (err == 0) {
1737                         transport->srcport = port;
1738                         break;
1739                 }
1740                 last = port;
1741                 port = xs_next_srcport(transport, port);
1742                 if (port > last)
1743                         nloop++;
1744         } while (err == -EADDRINUSE && nloop != 2);
1745
1746         if (myaddr.ss_family == AF_INET)
1747                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1748                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1749                                 port, err ? "failed" : "ok", err);
1750         else
1751                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1752                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1753                                 port, err ? "failed" : "ok", err);
1754         return err;
1755 }
1756
1757 /*
1758  * We don't support autobind on AF_LOCAL sockets
1759  */
1760 static void xs_local_rpcbind(struct rpc_task *task)
1761 {
1762         xprt_set_bound(task->tk_xprt);
1763 }
1764
1765 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1766 {
1767 }
1768
1769 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1770 static struct lock_class_key xs_key[2];
1771 static struct lock_class_key xs_slock_key[2];
1772
1773 static inline void xs_reclassify_socketu(struct socket *sock)
1774 {
1775         struct sock *sk = sock->sk;
1776
1777         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1778                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1779 }
1780
1781 static inline void xs_reclassify_socket4(struct socket *sock)
1782 {
1783         struct sock *sk = sock->sk;
1784
1785         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1786                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1787 }
1788
1789 static inline void xs_reclassify_socket6(struct socket *sock)
1790 {
1791         struct sock *sk = sock->sk;
1792
1793         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1794                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1795 }
1796
1797 static inline void xs_reclassify_socket(int family, struct socket *sock)
1798 {
1799         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1800                 return;
1801
1802         switch (family) {
1803         case AF_LOCAL:
1804                 xs_reclassify_socketu(sock);
1805                 break;
1806         case AF_INET:
1807                 xs_reclassify_socket4(sock);
1808                 break;
1809         case AF_INET6:
1810                 xs_reclassify_socket6(sock);
1811                 break;
1812         }
1813 }
1814 #else
1815 static inline void xs_reclassify_socket(int family, struct socket *sock)
1816 {
1817 }
1818 #endif
1819
1820 static void xs_dummy_setup_socket(struct work_struct *work)
1821 {
1822 }
1823
1824 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1825                 struct sock_xprt *transport, int family, int type,
1826                 int protocol, bool reuseport)
1827 {
1828         struct socket *sock;
1829         int err;
1830
1831         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1832         if (err < 0) {
1833                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1834                                 protocol, -err);
1835                 goto out;
1836         }
1837         xs_reclassify_socket(family, sock);
1838
1839         if (reuseport)
1840                 xs_sock_set_reuseport(sock);
1841
1842         err = xs_bind(transport, sock);
1843         if (err) {
1844                 sock_release(sock);
1845                 goto out;
1846         }
1847
1848         return sock;
1849 out:
1850         return ERR_PTR(err);
1851 }
1852
1853 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1854                                       struct socket *sock)
1855 {
1856         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1857                                                                         xprt);
1858
1859         if (!transport->inet) {
1860                 struct sock *sk = sock->sk;
1861
1862                 write_lock_bh(&sk->sk_callback_lock);
1863
1864                 xs_save_old_callbacks(transport, sk);
1865
1866                 sk->sk_user_data = xprt;
1867                 sk->sk_data_ready = xs_data_ready;
1868                 sk->sk_write_space = xs_udp_write_space;
1869                 sock_set_flag(sk, SOCK_FASYNC);
1870                 sk->sk_error_report = xs_error_report;
1871                 sk->sk_allocation = GFP_NOIO;
1872
1873                 xprt_clear_connected(xprt);
1874
1875                 /* Reset to new socket */
1876                 transport->sock = sock;
1877                 transport->inet = sk;
1878
1879                 write_unlock_bh(&sk->sk_callback_lock);
1880         }
1881
1882         xs_stream_reset_connect(transport);
1883
1884         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1885 }
1886
1887 /**
1888  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1889  * @transport: socket transport to connect
1890  */
1891 static int xs_local_setup_socket(struct sock_xprt *transport)
1892 {
1893         struct rpc_xprt *xprt = &transport->xprt;
1894         struct socket *sock;
1895         int status = -EIO;
1896
1897         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1898                                         SOCK_STREAM, 0, &sock, 1);
1899         if (status < 0) {
1900                 dprintk("RPC:       can't create AF_LOCAL "
1901                         "transport socket (%d).\n", -status);
1902                 goto out;
1903         }
1904         xs_reclassify_socket(AF_LOCAL, sock);
1905
1906         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1907                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1908
1909         status = xs_local_finish_connecting(xprt, sock);
1910         trace_rpc_socket_connect(xprt, sock, status);
1911         switch (status) {
1912         case 0:
1913                 dprintk("RPC:       xprt %p connected to %s\n",
1914                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1915                 xprt->stat.connect_count++;
1916                 xprt->stat.connect_time += (long)jiffies -
1917                                            xprt->stat.connect_start;
1918                 xprt_set_connected(xprt);
1919         case -ENOBUFS:
1920                 break;
1921         case -ENOENT:
1922                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1923                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1924                 break;
1925         case -ECONNREFUSED:
1926                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1927                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1928                 break;
1929         default:
1930                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1931                                 __func__, -status,
1932                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1933         }
1934
1935 out:
1936         xprt_clear_connecting(xprt);
1937         xprt_wake_pending_tasks(xprt, status);
1938         return status;
1939 }
1940
1941 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1942 {
1943         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1944         int ret;
1945
1946          if (RPC_IS_ASYNC(task)) {
1947                 /*
1948                  * We want the AF_LOCAL connect to be resolved in the
1949                  * filesystem namespace of the process making the rpc
1950                  * call.  Thus we connect synchronously.
1951                  *
1952                  * If we want to support asynchronous AF_LOCAL calls,
1953                  * we'll need to figure out how to pass a namespace to
1954                  * connect.
1955                  */
1956                 rpc_exit(task, -ENOTCONN);
1957                 return;
1958         }
1959         ret = xs_local_setup_socket(transport);
1960         if (ret && !RPC_IS_SOFTCONN(task))
1961                 msleep_interruptible(15000);
1962 }
1963
1964 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1965 /*
1966  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1967  * know that we have exclusive access to the socket), to guard against
1968  * races with xs_reset_transport.
1969  */
1970 static void xs_set_memalloc(struct rpc_xprt *xprt)
1971 {
1972         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1973                         xprt);
1974
1975         /*
1976          * If there's no sock, then we have nothing to set. The
1977          * reconnecting process will get it for us.
1978          */
1979         if (!transport->inet)
1980                 return;
1981         if (atomic_read(&xprt->swapper))
1982                 sk_set_memalloc(transport->inet);
1983 }
1984
1985 /**
1986  * xs_enable_swap - Tag this transport as being used for swap.
1987  * @xprt: transport to tag
1988  *
1989  * Take a reference to this transport on behalf of the rpc_clnt, and
1990  * optionally mark it for swapping if it wasn't already.
1991  */
1992 static int
1993 xs_enable_swap(struct rpc_xprt *xprt)
1994 {
1995         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1996
1997         if (atomic_inc_return(&xprt->swapper) != 1)
1998                 return 0;
1999         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2000                 return -ERESTARTSYS;
2001         if (xs->inet)
2002                 sk_set_memalloc(xs->inet);
2003         xprt_release_xprt(xprt, NULL);
2004         return 0;
2005 }
2006
2007 /**
2008  * xs_disable_swap - Untag this transport as being used for swap.
2009  * @xprt: transport to tag
2010  *
2011  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2012  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2013  */
2014 static void
2015 xs_disable_swap(struct rpc_xprt *xprt)
2016 {
2017         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2018
2019         if (!atomic_dec_and_test(&xprt->swapper))
2020                 return;
2021         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2022                 return;
2023         if (xs->inet)
2024                 sk_clear_memalloc(xs->inet);
2025         xprt_release_xprt(xprt, NULL);
2026 }
2027 #else
2028 static void xs_set_memalloc(struct rpc_xprt *xprt)
2029 {
2030 }
2031
2032 static int
2033 xs_enable_swap(struct rpc_xprt *xprt)
2034 {
2035         return -EINVAL;
2036 }
2037
2038 static void
2039 xs_disable_swap(struct rpc_xprt *xprt)
2040 {
2041 }
2042 #endif
2043
2044 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2045 {
2046         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2047
2048         if (!transport->inet) {
2049                 struct sock *sk = sock->sk;
2050
2051                 write_lock_bh(&sk->sk_callback_lock);
2052
2053                 xs_save_old_callbacks(transport, sk);
2054
2055                 sk->sk_user_data = xprt;
2056                 sk->sk_data_ready = xs_data_ready;
2057                 sk->sk_write_space = xs_udp_write_space;
2058                 sock_set_flag(sk, SOCK_FASYNC);
2059                 sk->sk_allocation = GFP_NOIO;
2060
2061                 xprt_set_connected(xprt);
2062
2063                 /* Reset to new socket */
2064                 transport->sock = sock;
2065                 transport->inet = sk;
2066
2067                 xs_set_memalloc(xprt);
2068
2069                 write_unlock_bh(&sk->sk_callback_lock);
2070         }
2071         xs_udp_do_set_buffer_size(xprt);
2072
2073         xprt->stat.connect_start = jiffies;
2074 }
2075
2076 static void xs_udp_setup_socket(struct work_struct *work)
2077 {
2078         struct sock_xprt *transport =
2079                 container_of(work, struct sock_xprt, connect_worker.work);
2080         struct rpc_xprt *xprt = &transport->xprt;
2081         struct socket *sock;
2082         int status = -EIO;
2083
2084         sock = xs_create_sock(xprt, transport,
2085                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2086                         IPPROTO_UDP, false);
2087         if (IS_ERR(sock))
2088                 goto out;
2089
2090         dprintk("RPC:       worker connecting xprt %p via %s to "
2091                                 "%s (port %s)\n", xprt,
2092                         xprt->address_strings[RPC_DISPLAY_PROTO],
2093                         xprt->address_strings[RPC_DISPLAY_ADDR],
2094                         xprt->address_strings[RPC_DISPLAY_PORT]);
2095
2096         xs_udp_finish_connecting(xprt, sock);
2097         trace_rpc_socket_connect(xprt, sock, 0);
2098         status = 0;
2099 out:
2100         xprt_unlock_connect(xprt, transport);
2101         xprt_clear_connecting(xprt);
2102         xprt_wake_pending_tasks(xprt, status);
2103 }
2104
2105 /**
2106  * xs_tcp_shutdown - gracefully shut down a TCP socket
2107  * @xprt: transport
2108  *
2109  * Initiates a graceful shutdown of the TCP socket by calling the
2110  * equivalent of shutdown(SHUT_RDWR);
2111  */
2112 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2113 {
2114         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2115         struct socket *sock = transport->sock;
2116         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2117
2118         if (sock == NULL)
2119                 return;
2120         switch (skst) {
2121         default:
2122                 kernel_sock_shutdown(sock, SHUT_RDWR);
2123                 trace_rpc_socket_shutdown(xprt, sock);
2124                 break;
2125         case TCP_CLOSE:
2126         case TCP_TIME_WAIT:
2127                 xs_reset_transport(transport);
2128         }
2129 }
2130
2131 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2132                 struct socket *sock)
2133 {
2134         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2135         unsigned int keepidle;
2136         unsigned int keepcnt;
2137         unsigned int opt_on = 1;
2138         unsigned int timeo;
2139
2140         spin_lock_bh(&xprt->transport_lock);
2141         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2142         keepcnt = xprt->timeout->to_retries + 1;
2143         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2144                 (xprt->timeout->to_retries + 1);
2145         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2146         spin_unlock_bh(&xprt->transport_lock);
2147
2148         /* TCP Keepalive options */
2149         kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2150                         (char *)&opt_on, sizeof(opt_on));
2151         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2152                         (char *)&keepidle, sizeof(keepidle));
2153         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2154                         (char *)&keepidle, sizeof(keepidle));
2155         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2156                         (char *)&keepcnt, sizeof(keepcnt));
2157
2158         /* TCP user timeout (see RFC5482) */
2159         kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2160                         (char *)&timeo, sizeof(timeo));
2161 }
2162
2163 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2164                 unsigned long connect_timeout,
2165                 unsigned long reconnect_timeout)
2166 {
2167         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2168         struct rpc_timeout to;
2169         unsigned long initval;
2170
2171         spin_lock_bh(&xprt->transport_lock);
2172         if (reconnect_timeout < xprt->max_reconnect_timeout)
2173                 xprt->max_reconnect_timeout = reconnect_timeout;
2174         if (connect_timeout < xprt->connect_timeout) {
2175                 memcpy(&to, xprt->timeout, sizeof(to));
2176                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2177                 /* Arbitrary lower limit */
2178                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2179                         initval = XS_TCP_INIT_REEST_TO << 1;
2180                 to.to_initval = initval;
2181                 to.to_maxval = initval;
2182                 memcpy(&transport->tcp_timeout, &to,
2183                                 sizeof(transport->tcp_timeout));
2184                 xprt->timeout = &transport->tcp_timeout;
2185                 xprt->connect_timeout = connect_timeout;
2186         }
2187         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2188         spin_unlock_bh(&xprt->transport_lock);
2189 }
2190
2191 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2192 {
2193         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2194         int ret = -ENOTCONN;
2195
2196         if (!transport->inet) {
2197                 struct sock *sk = sock->sk;
2198                 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2199
2200                 /* Avoid temporary address, they are bad for long-lived
2201                  * connections such as NFS mounts.
2202                  * RFC4941, section 3.6 suggests that:
2203                  *    Individual applications, which have specific
2204                  *    knowledge about the normal duration of connections,
2205                  *    MAY override this as appropriate.
2206                  */
2207                 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2208                                 (char *)&addr_pref, sizeof(addr_pref));
2209
2210                 xs_tcp_set_socket_timeouts(xprt, sock);
2211
2212                 write_lock_bh(&sk->sk_callback_lock);
2213
2214                 xs_save_old_callbacks(transport, sk);
2215
2216                 sk->sk_user_data = xprt;
2217                 sk->sk_data_ready = xs_data_ready;
2218                 sk->sk_state_change = xs_tcp_state_change;
2219                 sk->sk_write_space = xs_tcp_write_space;
2220                 sock_set_flag(sk, SOCK_FASYNC);
2221                 sk->sk_error_report = xs_error_report;
2222                 sk->sk_allocation = GFP_NOIO;
2223
2224                 /* socket options */
2225                 sock_reset_flag(sk, SOCK_LINGER);
2226                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2227
2228                 xprt_clear_connected(xprt);
2229
2230                 /* Reset to new socket */
2231                 transport->sock = sock;
2232                 transport->inet = sk;
2233
2234                 write_unlock_bh(&sk->sk_callback_lock);
2235         }
2236
2237         if (!xprt_bound(xprt))
2238                 goto out;
2239
2240         xs_set_memalloc(xprt);
2241
2242         /* Reset TCP record info */
2243         xs_stream_reset_connect(transport);
2244
2245         /* Tell the socket layer to start connecting... */
2246         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2247         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2248         switch (ret) {
2249         case 0:
2250                 xs_set_srcport(transport, sock);
2251                 /* fall through */
2252         case -EINPROGRESS:
2253                 /* SYN_SENT! */
2254                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2255                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2256                 break;
2257         case -EADDRNOTAVAIL:
2258                 /* Source port number is unavailable. Try a new one! */
2259                 transport->srcport = 0;
2260         }
2261 out:
2262         return ret;
2263 }
2264
2265 /**
2266  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2267  *
2268  * Invoked by a work queue tasklet.
2269  */
2270 static void xs_tcp_setup_socket(struct work_struct *work)
2271 {
2272         struct sock_xprt *transport =
2273                 container_of(work, struct sock_xprt, connect_worker.work);
2274         struct socket *sock = transport->sock;
2275         struct rpc_xprt *xprt = &transport->xprt;
2276         int status = -EIO;
2277
2278         if (!sock) {
2279                 sock = xs_create_sock(xprt, transport,
2280                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2281                                 IPPROTO_TCP, true);
2282                 if (IS_ERR(sock)) {
2283                         status = PTR_ERR(sock);
2284                         goto out;
2285                 }
2286         }
2287
2288         dprintk("RPC:       worker connecting xprt %p via %s to "
2289                                 "%s (port %s)\n", xprt,
2290                         xprt->address_strings[RPC_DISPLAY_PROTO],
2291                         xprt->address_strings[RPC_DISPLAY_ADDR],
2292                         xprt->address_strings[RPC_DISPLAY_PORT]);
2293
2294         status = xs_tcp_finish_connecting(xprt, sock);
2295         trace_rpc_socket_connect(xprt, sock, status);
2296         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2297                         xprt, -status, xprt_connected(xprt),
2298                         sock->sk->sk_state);
2299         switch (status) {
2300         default:
2301                 printk("%s: connect returned unhandled error %d\n",
2302                         __func__, status);
2303                 /* fall through */
2304         case -EADDRNOTAVAIL:
2305                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2306                  * and retry
2307                  */
2308                 xs_tcp_force_close(xprt);
2309                 break;
2310         case 0:
2311         case -EINPROGRESS:
2312         case -EALREADY:
2313                 xprt_unlock_connect(xprt, transport);
2314                 return;
2315         case -EINVAL:
2316                 /* Happens, for instance, if the user specified a link
2317                  * local IPv6 address without a scope-id.
2318                  */
2319         case -ECONNREFUSED:
2320         case -ECONNRESET:
2321         case -ENETDOWN:
2322         case -ENETUNREACH:
2323         case -EHOSTUNREACH:
2324         case -EADDRINUSE:
2325         case -ENOBUFS:
2326                 /*
2327                  * xs_tcp_force_close() wakes tasks with -EIO.
2328                  * We need to wake them first to ensure the
2329                  * correct error code.
2330                  */
2331                 xprt_wake_pending_tasks(xprt, status);
2332                 xs_tcp_force_close(xprt);
2333                 goto out;
2334         }
2335         status = -EAGAIN;
2336 out:
2337         xprt_unlock_connect(xprt, transport);
2338         xprt_clear_connecting(xprt);
2339         xprt_wake_pending_tasks(xprt, status);
2340 }
2341
2342 static unsigned long xs_reconnect_delay(const struct rpc_xprt *xprt)
2343 {
2344         unsigned long start, now = jiffies;
2345
2346         start = xprt->stat.connect_start + xprt->reestablish_timeout;
2347         if (time_after(start, now))
2348                 return start - now;
2349         return 0;
2350 }
2351
2352 static void xs_reconnect_backoff(struct rpc_xprt *xprt)
2353 {
2354         xprt->reestablish_timeout <<= 1;
2355         if (xprt->reestablish_timeout > xprt->max_reconnect_timeout)
2356                 xprt->reestablish_timeout = xprt->max_reconnect_timeout;
2357         if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2358                 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2359 }
2360
2361 /**
2362  * xs_connect - connect a socket to a remote endpoint
2363  * @xprt: pointer to transport structure
2364  * @task: address of RPC task that manages state of connect request
2365  *
2366  * TCP: If the remote end dropped the connection, delay reconnecting.
2367  *
2368  * UDP socket connects are synchronous, but we use a work queue anyway
2369  * to guarantee that even unprivileged user processes can set up a
2370  * socket on a privileged port.
2371  *
2372  * If a UDP socket connect fails, the delay behavior here prevents
2373  * retry floods (hard mounts).
2374  */
2375 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2376 {
2377         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2378         unsigned long delay = 0;
2379
2380         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2381
2382         if (transport->sock != NULL) {
2383                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2384                                 "seconds\n",
2385                                 xprt, xprt->reestablish_timeout / HZ);
2386
2387                 /* Start by resetting any existing state */
2388                 xs_reset_transport(transport);
2389
2390                 delay = xs_reconnect_delay(xprt);
2391                 xs_reconnect_backoff(xprt);
2392
2393         } else
2394                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2395
2396         queue_delayed_work(xprtiod_workqueue,
2397                         &transport->connect_worker,
2398                         delay);
2399 }
2400
2401 /**
2402  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2403  * @xprt: rpc_xprt struct containing statistics
2404  * @seq: output file
2405  *
2406  */
2407 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2408 {
2409         long idle_time = 0;
2410
2411         if (xprt_connected(xprt))
2412                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2413
2414         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2415                         "%llu %llu %lu %llu %llu\n",
2416                         xprt->stat.bind_count,
2417                         xprt->stat.connect_count,
2418                         xprt->stat.connect_time / HZ,
2419                         idle_time,
2420                         xprt->stat.sends,
2421                         xprt->stat.recvs,
2422                         xprt->stat.bad_xids,
2423                         xprt->stat.req_u,
2424                         xprt->stat.bklog_u,
2425                         xprt->stat.max_slots,
2426                         xprt->stat.sending_u,
2427                         xprt->stat.pending_u);
2428 }
2429
2430 /**
2431  * xs_udp_print_stats - display UDP socket-specifc stats
2432  * @xprt: rpc_xprt struct containing statistics
2433  * @seq: output file
2434  *
2435  */
2436 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2437 {
2438         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2439
2440         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2441                         "%lu %llu %llu\n",
2442                         transport->srcport,
2443                         xprt->stat.bind_count,
2444                         xprt->stat.sends,
2445                         xprt->stat.recvs,
2446                         xprt->stat.bad_xids,
2447                         xprt->stat.req_u,
2448                         xprt->stat.bklog_u,
2449                         xprt->stat.max_slots,
2450                         xprt->stat.sending_u,
2451                         xprt->stat.pending_u);
2452 }
2453
2454 /**
2455  * xs_tcp_print_stats - display TCP socket-specifc stats
2456  * @xprt: rpc_xprt struct containing statistics
2457  * @seq: output file
2458  *
2459  */
2460 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2461 {
2462         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2463         long idle_time = 0;
2464
2465         if (xprt_connected(xprt))
2466                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2467
2468         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2469                         "%llu %llu %lu %llu %llu\n",
2470                         transport->srcport,
2471                         xprt->stat.bind_count,
2472                         xprt->stat.connect_count,
2473                         xprt->stat.connect_time / HZ,
2474                         idle_time,
2475                         xprt->stat.sends,
2476                         xprt->stat.recvs,
2477                         xprt->stat.bad_xids,
2478                         xprt->stat.req_u,
2479                         xprt->stat.bklog_u,
2480                         xprt->stat.max_slots,
2481                         xprt->stat.sending_u,
2482                         xprt->stat.pending_u);
2483 }
2484
2485 /*
2486  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2487  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2488  * to use the server side send routines.
2489  */
2490 static int bc_malloc(struct rpc_task *task)
2491 {
2492         struct rpc_rqst *rqst = task->tk_rqstp;
2493         size_t size = rqst->rq_callsize;
2494         struct page *page;
2495         struct rpc_buffer *buf;
2496
2497         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2498                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2499                           size);
2500                 return -EINVAL;
2501         }
2502
2503         page = alloc_page(GFP_KERNEL);
2504         if (!page)
2505                 return -ENOMEM;
2506
2507         buf = page_address(page);
2508         buf->len = PAGE_SIZE;
2509
2510         rqst->rq_buffer = buf->data;
2511         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2512         return 0;
2513 }
2514
2515 /*
2516  * Free the space allocated in the bc_alloc routine
2517  */
2518 static void bc_free(struct rpc_task *task)
2519 {
2520         void *buffer = task->tk_rqstp->rq_buffer;
2521         struct rpc_buffer *buf;
2522
2523         buf = container_of(buffer, struct rpc_buffer, data);
2524         free_page((unsigned long)buf);
2525 }
2526
2527 /*
2528  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2529  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2530  */
2531 static int bc_sendto(struct rpc_rqst *req)
2532 {
2533         int len;
2534         struct xdr_buf *xbufp = &req->rq_snd_buf;
2535         struct rpc_xprt *xprt = req->rq_xprt;
2536         struct sock_xprt *transport =
2537                                 container_of(xprt, struct sock_xprt, xprt);
2538         struct socket *sock = transport->sock;
2539         unsigned long headoff;
2540         unsigned long tailoff;
2541
2542         xs_encode_stream_record_marker(xbufp);
2543
2544         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2545         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2546         len = svc_send_common(sock, xbufp,
2547                               virt_to_page(xbufp->head[0].iov_base), headoff,
2548                               xbufp->tail[0].iov_base, tailoff);
2549
2550         if (len != xbufp->len) {
2551                 printk(KERN_NOTICE "Error sending entire callback!\n");
2552                 len = -EAGAIN;
2553         }
2554
2555         return len;
2556 }
2557
2558 /*
2559  * The send routine. Borrows from svc_send
2560  */
2561 static int bc_send_request(struct rpc_rqst *req)
2562 {
2563         struct svc_xprt *xprt;
2564         int len;
2565
2566         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2567         /*
2568          * Get the server socket associated with this callback xprt
2569          */
2570         xprt = req->rq_xprt->bc_xprt;
2571
2572         /*
2573          * Grab the mutex to serialize data as the connection is shared
2574          * with the fore channel
2575          */
2576         mutex_lock(&xprt->xpt_mutex);
2577         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2578                 len = -ENOTCONN;
2579         else
2580                 len = bc_sendto(req);
2581         mutex_unlock(&xprt->xpt_mutex);
2582
2583         if (len > 0)
2584                 len = 0;
2585
2586         return len;
2587 }
2588
2589 /*
2590  * The close routine. Since this is client initiated, we do nothing
2591  */
2592
2593 static void bc_close(struct rpc_xprt *xprt)
2594 {
2595 }
2596
2597 /*
2598  * The xprt destroy routine. Again, because this connection is client
2599  * initiated, we do nothing
2600  */
2601
2602 static void bc_destroy(struct rpc_xprt *xprt)
2603 {
2604         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2605
2606         xs_xprt_free(xprt);
2607         module_put(THIS_MODULE);
2608 }
2609
2610 static const struct rpc_xprt_ops xs_local_ops = {
2611         .reserve_xprt           = xprt_reserve_xprt,
2612         .release_xprt           = xprt_release_xprt,
2613         .alloc_slot             = xprt_alloc_slot,
2614         .free_slot              = xprt_free_slot,
2615         .rpcbind                = xs_local_rpcbind,
2616         .set_port               = xs_local_set_port,
2617         .connect                = xs_local_connect,
2618         .buf_alloc              = rpc_malloc,
2619         .buf_free               = rpc_free,
2620         .prepare_request        = xs_stream_prepare_request,
2621         .send_request           = xs_local_send_request,
2622         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2623         .close                  = xs_close,
2624         .destroy                = xs_destroy,
2625         .print_stats            = xs_local_print_stats,
2626         .enable_swap            = xs_enable_swap,
2627         .disable_swap           = xs_disable_swap,
2628 };
2629
2630 static const struct rpc_xprt_ops xs_udp_ops = {
2631         .set_buffer_size        = xs_udp_set_buffer_size,
2632         .reserve_xprt           = xprt_reserve_xprt_cong,
2633         .release_xprt           = xprt_release_xprt_cong,
2634         .alloc_slot             = xprt_alloc_slot,
2635         .free_slot              = xprt_free_slot,
2636         .rpcbind                = rpcb_getport_async,
2637         .set_port               = xs_set_port,
2638         .connect                = xs_connect,
2639         .buf_alloc              = rpc_malloc,
2640         .buf_free               = rpc_free,
2641         .send_request           = xs_udp_send_request,
2642         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2643         .timer                  = xs_udp_timer,
2644         .release_request        = xprt_release_rqst_cong,
2645         .close                  = xs_close,
2646         .destroy                = xs_destroy,
2647         .print_stats            = xs_udp_print_stats,
2648         .enable_swap            = xs_enable_swap,
2649         .disable_swap           = xs_disable_swap,
2650         .inject_disconnect      = xs_inject_disconnect,
2651 };
2652
2653 static const struct rpc_xprt_ops xs_tcp_ops = {
2654         .reserve_xprt           = xprt_reserve_xprt,
2655         .release_xprt           = xprt_release_xprt,
2656         .alloc_slot             = xprt_alloc_slot,
2657         .free_slot              = xprt_free_slot,
2658         .rpcbind                = rpcb_getport_async,
2659         .set_port               = xs_set_port,
2660         .connect                = xs_connect,
2661         .buf_alloc              = rpc_malloc,
2662         .buf_free               = rpc_free,
2663         .prepare_request        = xs_stream_prepare_request,
2664         .send_request           = xs_tcp_send_request,
2665         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2666         .close                  = xs_tcp_shutdown,
2667         .destroy                = xs_destroy,
2668         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2669         .print_stats            = xs_tcp_print_stats,
2670         .enable_swap            = xs_enable_swap,
2671         .disable_swap           = xs_disable_swap,
2672         .inject_disconnect      = xs_inject_disconnect,
2673 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2674         .bc_setup               = xprt_setup_bc,
2675         .bc_up                  = xs_tcp_bc_up,
2676         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2677         .bc_free_rqst           = xprt_free_bc_rqst,
2678         .bc_destroy             = xprt_destroy_bc,
2679 #endif
2680 };
2681
2682 /*
2683  * The rpc_xprt_ops for the server backchannel
2684  */
2685
2686 static const struct rpc_xprt_ops bc_tcp_ops = {
2687         .reserve_xprt           = xprt_reserve_xprt,
2688         .release_xprt           = xprt_release_xprt,
2689         .alloc_slot             = xprt_alloc_slot,
2690         .free_slot              = xprt_free_slot,
2691         .buf_alloc              = bc_malloc,
2692         .buf_free               = bc_free,
2693         .send_request           = bc_send_request,
2694         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2695         .close                  = bc_close,
2696         .destroy                = bc_destroy,
2697         .print_stats            = xs_tcp_print_stats,
2698         .enable_swap            = xs_enable_swap,
2699         .disable_swap           = xs_disable_swap,
2700         .inject_disconnect      = xs_inject_disconnect,
2701 };
2702
2703 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2704 {
2705         static const struct sockaddr_in sin = {
2706                 .sin_family             = AF_INET,
2707                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2708         };
2709         static const struct sockaddr_in6 sin6 = {
2710                 .sin6_family            = AF_INET6,
2711                 .sin6_addr              = IN6ADDR_ANY_INIT,
2712         };
2713
2714         switch (family) {
2715         case AF_LOCAL:
2716                 break;
2717         case AF_INET:
2718                 memcpy(sap, &sin, sizeof(sin));
2719                 break;
2720         case AF_INET6:
2721                 memcpy(sap, &sin6, sizeof(sin6));
2722                 break;
2723         default:
2724                 dprintk("RPC:       %s: Bad address family\n", __func__);
2725                 return -EAFNOSUPPORT;
2726         }
2727         return 0;
2728 }
2729
2730 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2731                                       unsigned int slot_table_size,
2732                                       unsigned int max_slot_table_size)
2733 {
2734         struct rpc_xprt *xprt;
2735         struct sock_xprt *new;
2736
2737         if (args->addrlen > sizeof(xprt->addr)) {
2738                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2739                 return ERR_PTR(-EBADF);
2740         }
2741
2742         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2743                         max_slot_table_size);
2744         if (xprt == NULL) {
2745                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2746                                 "rpc_xprt\n");
2747                 return ERR_PTR(-ENOMEM);
2748         }
2749
2750         new = container_of(xprt, struct sock_xprt, xprt);
2751         mutex_init(&new->recv_mutex);
2752         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2753         xprt->addrlen = args->addrlen;
2754         if (args->srcaddr)
2755                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2756         else {
2757                 int err;
2758                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2759                                         (struct sockaddr *)&new->srcaddr);
2760                 if (err != 0) {
2761                         xprt_free(xprt);
2762                         return ERR_PTR(err);
2763                 }
2764         }
2765
2766         return xprt;
2767 }
2768
2769 static const struct rpc_timeout xs_local_default_timeout = {
2770         .to_initval = 10 * HZ,
2771         .to_maxval = 10 * HZ,
2772         .to_retries = 2,
2773 };
2774
2775 /**
2776  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2777  * @args: rpc transport creation arguments
2778  *
2779  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2780  */
2781 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2782 {
2783         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2784         struct sock_xprt *transport;
2785         struct rpc_xprt *xprt;
2786         struct rpc_xprt *ret;
2787
2788         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2789                         xprt_max_tcp_slot_table_entries);
2790         if (IS_ERR(xprt))
2791                 return xprt;
2792         transport = container_of(xprt, struct sock_xprt, xprt);
2793
2794         xprt->prot = 0;
2795         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2796         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2797
2798         xprt->bind_timeout = XS_BIND_TO;
2799         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2800         xprt->idle_timeout = XS_IDLE_DISC_TO;
2801
2802         xprt->ops = &xs_local_ops;
2803         xprt->timeout = &xs_local_default_timeout;
2804
2805         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2806         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2807
2808         switch (sun->sun_family) {
2809         case AF_LOCAL:
2810                 if (sun->sun_path[0] != '/') {
2811                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2812                                         sun->sun_path);
2813                         ret = ERR_PTR(-EINVAL);
2814                         goto out_err;
2815                 }
2816                 xprt_set_bound(xprt);
2817                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2818                 ret = ERR_PTR(xs_local_setup_socket(transport));
2819                 if (ret)
2820                         goto out_err;
2821                 break;
2822         default:
2823                 ret = ERR_PTR(-EAFNOSUPPORT);
2824                 goto out_err;
2825         }
2826
2827         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2828                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2829
2830         if (try_module_get(THIS_MODULE))
2831                 return xprt;
2832         ret = ERR_PTR(-EINVAL);
2833 out_err:
2834         xs_xprt_free(xprt);
2835         return ret;
2836 }
2837
2838 static const struct rpc_timeout xs_udp_default_timeout = {
2839         .to_initval = 5 * HZ,
2840         .to_maxval = 30 * HZ,
2841         .to_increment = 5 * HZ,
2842         .to_retries = 5,
2843 };
2844
2845 /**
2846  * xs_setup_udp - Set up transport to use a UDP socket
2847  * @args: rpc transport creation arguments
2848  *
2849  */
2850 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2851 {
2852         struct sockaddr *addr = args->dstaddr;
2853         struct rpc_xprt *xprt;
2854         struct sock_xprt *transport;
2855         struct rpc_xprt *ret;
2856
2857         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2858                         xprt_udp_slot_table_entries);
2859         if (IS_ERR(xprt))
2860                 return xprt;
2861         transport = container_of(xprt, struct sock_xprt, xprt);
2862
2863         xprt->prot = IPPROTO_UDP;
2864         xprt->tsh_size = 0;
2865         /* XXX: header size can vary due to auth type, IPv6, etc. */
2866         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2867
2868         xprt->bind_timeout = XS_BIND_TO;
2869         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2870         xprt->idle_timeout = XS_IDLE_DISC_TO;
2871
2872         xprt->ops = &xs_udp_ops;
2873
2874         xprt->timeout = &xs_udp_default_timeout;
2875
2876         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2877         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2878
2879         switch (addr->sa_family) {
2880         case AF_INET:
2881                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2882                         xprt_set_bound(xprt);
2883
2884                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2885                 break;
2886         case AF_INET6:
2887                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2888                         xprt_set_bound(xprt);
2889
2890                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2891                 break;
2892         default:
2893                 ret = ERR_PTR(-EAFNOSUPPORT);
2894                 goto out_err;
2895         }
2896
2897         if (xprt_bound(xprt))
2898                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2899                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2900                                 xprt->address_strings[RPC_DISPLAY_PORT],
2901                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2902         else
2903                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2904                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2905                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2906
2907         if (try_module_get(THIS_MODULE))
2908                 return xprt;
2909         ret = ERR_PTR(-EINVAL);
2910 out_err:
2911         xs_xprt_free(xprt);
2912         return ret;
2913 }
2914
2915 static const struct rpc_timeout xs_tcp_default_timeout = {
2916         .to_initval = 60 * HZ,
2917         .to_maxval = 60 * HZ,
2918         .to_retries = 2,
2919 };
2920
2921 /**
2922  * xs_setup_tcp - Set up transport to use a TCP socket
2923  * @args: rpc transport creation arguments
2924  *
2925  */
2926 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2927 {
2928         struct sockaddr *addr = args->dstaddr;
2929         struct rpc_xprt *xprt;
2930         struct sock_xprt *transport;
2931         struct rpc_xprt *ret;
2932         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2933
2934         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2935                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2936
2937         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2938                         max_slot_table_size);
2939         if (IS_ERR(xprt))
2940                 return xprt;
2941         transport = container_of(xprt, struct sock_xprt, xprt);
2942
2943         xprt->prot = IPPROTO_TCP;
2944         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2945         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2946
2947         xprt->bind_timeout = XS_BIND_TO;
2948         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2949         xprt->idle_timeout = XS_IDLE_DISC_TO;
2950
2951         xprt->ops = &xs_tcp_ops;
2952         xprt->timeout = &xs_tcp_default_timeout;
2953
2954         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2955         xprt->connect_timeout = xprt->timeout->to_initval *
2956                 (xprt->timeout->to_retries + 1);
2957
2958         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2959         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2960
2961         switch (addr->sa_family) {
2962         case AF_INET:
2963                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2964                         xprt_set_bound(xprt);
2965
2966                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2967                 break;
2968         case AF_INET6:
2969                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2970                         xprt_set_bound(xprt);
2971
2972                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2973                 break;
2974         default:
2975                 ret = ERR_PTR(-EAFNOSUPPORT);
2976                 goto out_err;
2977         }
2978
2979         if (xprt_bound(xprt))
2980                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2981                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2982                                 xprt->address_strings[RPC_DISPLAY_PORT],
2983                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2984         else
2985                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2986                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2987                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2988
2989         if (try_module_get(THIS_MODULE))
2990                 return xprt;
2991         ret = ERR_PTR(-EINVAL);
2992 out_err:
2993         xs_xprt_free(xprt);
2994         return ret;
2995 }
2996
2997 /**
2998  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2999  * @args: rpc transport creation arguments
3000  *
3001  */
3002 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3003 {
3004         struct sockaddr *addr = args->dstaddr;
3005         struct rpc_xprt *xprt;
3006         struct sock_xprt *transport;
3007         struct svc_sock *bc_sock;
3008         struct rpc_xprt *ret;
3009
3010         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3011                         xprt_tcp_slot_table_entries);
3012         if (IS_ERR(xprt))
3013                 return xprt;
3014         transport = container_of(xprt, struct sock_xprt, xprt);
3015
3016         xprt->prot = IPPROTO_TCP;
3017         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3018         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3019         xprt->timeout = &xs_tcp_default_timeout;
3020
3021         /* backchannel */
3022         xprt_set_bound(xprt);
3023         xprt->bind_timeout = 0;
3024         xprt->reestablish_timeout = 0;
3025         xprt->idle_timeout = 0;
3026
3027         xprt->ops = &bc_tcp_ops;
3028
3029         switch (addr->sa_family) {
3030         case AF_INET:
3031                 xs_format_peer_addresses(xprt, "tcp",
3032                                          RPCBIND_NETID_TCP);
3033                 break;
3034         case AF_INET6:
3035                 xs_format_peer_addresses(xprt, "tcp",
3036                                    RPCBIND_NETID_TCP6);
3037                 break;
3038         default:
3039                 ret = ERR_PTR(-EAFNOSUPPORT);
3040                 goto out_err;
3041         }
3042
3043         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3044                         xprt->address_strings[RPC_DISPLAY_ADDR],
3045                         xprt->address_strings[RPC_DISPLAY_PORT],
3046                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3047
3048         /*
3049          * Once we've associated a backchannel xprt with a connection,
3050          * we want to keep it around as long as the connection lasts,
3051          * in case we need to start using it for a backchannel again;
3052          * this reference won't be dropped until bc_xprt is destroyed.
3053          */
3054         xprt_get(xprt);
3055         args->bc_xprt->xpt_bc_xprt = xprt;
3056         xprt->bc_xprt = args->bc_xprt;
3057         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3058         transport->sock = bc_sock->sk_sock;
3059         transport->inet = bc_sock->sk_sk;
3060
3061         /*
3062          * Since we don't want connections for the backchannel, we set
3063          * the xprt status to connected
3064          */
3065         xprt_set_connected(xprt);
3066
3067         if (try_module_get(THIS_MODULE))
3068                 return xprt;
3069
3070         args->bc_xprt->xpt_bc_xprt = NULL;
3071         args->bc_xprt->xpt_bc_xps = NULL;
3072         xprt_put(xprt);
3073         ret = ERR_PTR(-EINVAL);
3074 out_err:
3075         xs_xprt_free(xprt);
3076         return ret;
3077 }
3078
3079 static struct xprt_class        xs_local_transport = {
3080         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3081         .name           = "named UNIX socket",
3082         .owner          = THIS_MODULE,
3083         .ident          = XPRT_TRANSPORT_LOCAL,
3084         .setup          = xs_setup_local,
3085 };
3086
3087 static struct xprt_class        xs_udp_transport = {
3088         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3089         .name           = "udp",
3090         .owner          = THIS_MODULE,
3091         .ident          = XPRT_TRANSPORT_UDP,
3092         .setup          = xs_setup_udp,
3093 };
3094
3095 static struct xprt_class        xs_tcp_transport = {
3096         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3097         .name           = "tcp",
3098         .owner          = THIS_MODULE,
3099         .ident          = XPRT_TRANSPORT_TCP,
3100         .setup          = xs_setup_tcp,
3101 };
3102
3103 static struct xprt_class        xs_bc_tcp_transport = {
3104         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3105         .name           = "tcp NFSv4.1 backchannel",
3106         .owner          = THIS_MODULE,
3107         .ident          = XPRT_TRANSPORT_BC_TCP,
3108         .setup          = xs_setup_bc_tcp,
3109 };
3110
3111 /**
3112  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3113  *
3114  */
3115 int init_socket_xprt(void)
3116 {
3117 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3118         if (!sunrpc_table_header)
3119                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3120 #endif
3121
3122         xprt_register_transport(&xs_local_transport);
3123         xprt_register_transport(&xs_udp_transport);
3124         xprt_register_transport(&xs_tcp_transport);
3125         xprt_register_transport(&xs_bc_tcp_transport);
3126
3127         return 0;
3128 }
3129
3130 /**
3131  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3132  *
3133  */
3134 void cleanup_socket_xprt(void)
3135 {
3136 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3137         if (sunrpc_table_header) {
3138                 unregister_sysctl_table(sunrpc_table_header);
3139                 sunrpc_table_header = NULL;
3140         }
3141 #endif
3142
3143         xprt_unregister_transport(&xs_local_transport);
3144         xprt_unregister_transport(&xs_udp_transport);
3145         xprt_unregister_transport(&xs_tcp_transport);
3146         xprt_unregister_transport(&xs_bc_tcp_transport);
3147 }
3148
3149 static int param_set_uint_minmax(const char *val,
3150                 const struct kernel_param *kp,
3151                 unsigned int min, unsigned int max)
3152 {
3153         unsigned int num;
3154         int ret;
3155
3156         if (!val)
3157                 return -EINVAL;
3158         ret = kstrtouint(val, 0, &num);
3159         if (ret)
3160                 return ret;
3161         if (num < min || num > max)
3162                 return -EINVAL;
3163         *((unsigned int *)kp->arg) = num;
3164         return 0;
3165 }
3166
3167 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3168 {
3169         return param_set_uint_minmax(val, kp,
3170                         RPC_MIN_RESVPORT,
3171                         RPC_MAX_RESVPORT);
3172 }
3173
3174 static const struct kernel_param_ops param_ops_portnr = {
3175         .set = param_set_portnr,
3176         .get = param_get_uint,
3177 };
3178
3179 #define param_check_portnr(name, p) \
3180         __param_check(name, p, unsigned int);
3181
3182 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3183 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3184
3185 static int param_set_slot_table_size(const char *val,
3186                                      const struct kernel_param *kp)
3187 {
3188         return param_set_uint_minmax(val, kp,
3189                         RPC_MIN_SLOT_TABLE,
3190                         RPC_MAX_SLOT_TABLE);
3191 }
3192
3193 static const struct kernel_param_ops param_ops_slot_table_size = {
3194         .set = param_set_slot_table_size,
3195         .get = param_get_uint,
3196 };
3197
3198 #define param_check_slot_table_size(name, p) \
3199         __param_check(name, p, unsigned int);
3200
3201 static int param_set_max_slot_table_size(const char *val,
3202                                      const struct kernel_param *kp)
3203 {
3204         return param_set_uint_minmax(val, kp,
3205                         RPC_MIN_SLOT_TABLE,
3206                         RPC_MAX_SLOT_TABLE_LIMIT);
3207 }
3208
3209 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3210         .set = param_set_max_slot_table_size,
3211         .get = param_get_uint,
3212 };
3213
3214 #define param_check_max_slot_table_size(name, p) \
3215         __param_check(name, p, unsigned int);
3216
3217 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3218                    slot_table_size, 0644);
3219 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3220                    max_slot_table_size, 0644);
3221 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3222                    slot_table_size, 0644);