git.rot13.org Git - linux/blob - 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 (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 334                 return want;
 335         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 336         for (i = 0; i < n; i++) {
 337                 if (buf->pages[i])
 338                         continue;
 339                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 340                 if (!buf->pages[i]) {
 341                         i *= PAGE_SIZE;
 342                         return i > buf->page_base ? i - buf->page_base : 0;
 343                 }
 344         }
 345         return want;
 346 }
 347
 348 static ssize_t
 349 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 350 {
 351         ssize_t ret;
 352         if (seek != 0)
 353                 iov_iter_advance(&msg->msg_iter, seek);
 354         ret = sock_recvmsg(sock, msg, flags);
 355         return ret > 0 ? ret + seek : ret;
 356 }
 357
 358 static ssize_t
 359 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 360                 struct kvec *kvec, size_t count, size_t seek)
 361 {
 362         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 363         return xs_sock_recvmsg(sock, msg, flags, seek);
 364 }
 365
 366 static ssize_t
 367 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 368                 struct bio_vec *bvec, unsigned long nr, size_t count,
 369                 size_t seek)
 370 {
 371         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 372         return xs_sock_recvmsg(sock, msg, flags, seek);
 373 }
 374
 375 static ssize_t
 376 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 377                 size_t count)
 378 {
 379         iov_iter_discard(&msg->msg_iter, READ, count);
 380         return sock_recvmsg(sock, msg, flags);
 381 }
 382
 383 static ssize_t
 384 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 385                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 386 {
 387         size_t want, seek_init = seek, offset = 0;
 388         ssize_t ret;
 389
 390         if (seek < buf->head[0].iov_len) {
 391                 want = min_t(size_t, count, buf->head[0].iov_len);
 392                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 393                 if (ret <= 0)
 394                         goto sock_err;
 395                 offset += ret;
 396                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 397                         goto out;
 398                 if (ret != want)
 399                         goto out;
 400                 seek = 0;
 401         } else {
 402                 seek -= buf->head[0].iov_len;
 403                 offset += buf->head[0].iov_len;
 404         }
 405
 406         want = xs_alloc_sparse_pages(buf,
 407                         min_t(size_t, count - offset, buf->page_len),
 408                         GFP_NOWAIT);
 409         if (seek < want) {
 410                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 411                                 xdr_buf_pagecount(buf),
 412                                 want + buf->page_base,
 413                                 seek + buf->page_base);
 414                 if (ret <= 0)
 415                         goto sock_err;
 416                 offset += ret - buf->page_base;
 417                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 418                         goto out;
 419                 if (ret != want)
 420                         goto out;
 421                 seek = 0;
 422         } else {
 423                 seek -= want;
 424                 offset += want;
 425         }
 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 out;
 437         } else
 438                 offset += buf->tail[0].iov_len;
 439         ret = -EMSGSIZE;
 440 out:
 441         *read = offset - seek_init;
 442         return ret;
 443 sock_err:
 444         offset += seek;
 445         goto out;
 446 }
 447
 448 static void
 449 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 450 {
 451         if (!transport->recv.copied) {
 452                 if (buf->head[0].iov_len >= transport->recv.offset)
 453                         memcpy(buf->head[0].iov_base,
 454                                         &transport->recv.xid,
 455                                         transport->recv.offset);
 456                 transport->recv.copied = transport->recv.offset;
 457         }
 458 }
 459
 460 static bool
 461 xs_read_stream_request_done(struct sock_xprt *transport)
 462 {
 463         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 464 }
 465
 466 static ssize_t
 467 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 468                 int flags, struct rpc_rqst *req)
 469 {
 470         struct xdr_buf *buf = &req->rq_private_buf;
 471         size_t want, read;
 472         ssize_t ret;
 473
 474         xs_read_header(transport, buf);
 475
 476         want = transport->recv.len - transport->recv.offset;
 477         ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 478                         transport->recv.copied + want, transport->recv.copied,
 479                         &read);
 480         transport->recv.offset += read;
 481         transport->recv.copied += read;
 482         if (transport->recv.offset == transport->recv.len) {
 483                 if (xs_read_stream_request_done(transport))
 484                         msg->msg_flags |= MSG_EOR;
 485                 return read;
 486         }
 487
 488         switch (ret) {
 489         default:
 490                 break;
 491         case -EFAULT:
 492         case -EMSGSIZE:
 493                 msg->msg_flags |= MSG_TRUNC;
 494                 return read;
 495         case 0:
 496                 return -ESHUTDOWN;
 497         }
 498         return ret < 0 ? ret : read;
 499 }
 500
 501 static size_t
 502 xs_read_stream_headersize(bool isfrag)
 503 {
 504         if (isfrag)
 505                 return sizeof(__be32);
 506         return 3 * sizeof(__be32);
 507 }
 508
 509 static ssize_t
 510 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 511                 int flags, size_t want, size_t seek)
 512 {
 513         struct kvec kvec = {
 514                 .iov_base = &transport->recv.fraghdr,
 515                 .iov_len = want,
 516         };
 517         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 518 }
 519
 520 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 521 static ssize_t
 522 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 523 {
 524         struct rpc_xprt *xprt = &transport->xprt;
 525         struct rpc_rqst *req;
 526         ssize_t ret;
 527
 528         /* Look up and lock the request corresponding to the given XID */
 529         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 530         if (!req) {
 531                 printk(KERN_WARNING "Callback slot table overflowed\n");
 532                 return -ESHUTDOWN;
 533         }
 534
 535         ret = xs_read_stream_request(transport, msg, flags, req);
 536         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 537                 xprt_complete_bc_request(req, transport->recv.copied);
 538
 539         return ret;
 540 }
 541 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 542 static ssize_t
 543 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 544 {
 545         return -ESHUTDOWN;
 546 }
 547 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 548
 549 static ssize_t
 550 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 551 {
 552         struct rpc_xprt *xprt = &transport->xprt;
 553         struct rpc_rqst *req;
 554         ssize_t ret = 0;
 555
 556         /* Look up and lock the request corresponding to the given XID */
 557         spin_lock(&xprt->queue_lock);
 558         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 559         if (!req) {
 560                 msg->msg_flags |= MSG_TRUNC;
 561                 goto out;
 562         }
 563         xprt_pin_rqst(req);
 564         spin_unlock(&xprt->queue_lock);
 565
 566         ret = xs_read_stream_request(transport, msg, flags, req);
 567
 568         spin_lock(&xprt->queue_lock);
 569         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 570                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 571         xprt_unpin_rqst(req);
 572 out:
 573         spin_unlock(&xprt->queue_lock);
 574         return ret;
 575 }
 576
 577 static ssize_t
 578 xs_read_stream(struct sock_xprt *transport, int flags)
 579 {
 580         struct msghdr msg = { 0 };
 581         size_t want, read = 0;
 582         ssize_t ret = 0;
 583
 584         if (transport->recv.len == 0) {
 585                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 586                 ret = xs_read_stream_header(transport, &msg, flags, want,
 587                                 transport->recv.offset);
 588                 if (ret <= 0)
 589                         goto out_err;
 590                 transport->recv.offset = ret;
 591                 if (transport->recv.offset != want)
 592                         return transport->recv.offset;
 593                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 594                         RPC_FRAGMENT_SIZE_MASK;
 595                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 596                 read = ret;
 597         }
 598
 599         switch (be32_to_cpu(transport->recv.calldir)) {
 600         default:
 601                 msg.msg_flags |= MSG_TRUNC;
 602                 break;
 603         case RPC_CALL:
 604                 ret = xs_read_stream_call(transport, &msg, flags);
 605                 break;
 606         case RPC_REPLY:
 607                 ret = xs_read_stream_reply(transport, &msg, flags);
 608         }
 609         if (msg.msg_flags & MSG_TRUNC) {
 610                 transport->recv.calldir = cpu_to_be32(-1);
 611                 transport->recv.copied = -1;
 612         }
 613         if (ret < 0)
 614                 goto out_err;
 615         read += ret;
 616         if (transport->recv.offset < transport->recv.len) {
 617                 if (!(msg.msg_flags & MSG_TRUNC))
 618                         return read;
 619                 msg.msg_flags = 0;
 620                 ret = xs_read_discard(transport->sock, &msg, flags,
 621                                 transport->recv.len - transport->recv.offset);
 622                 if (ret <= 0)
 623                         goto out_err;
 624                 transport->recv.offset += ret;
 625                 read += ret;
 626                 if (transport->recv.offset != transport->recv.len)
 627                         return read;
 628         }
 629         if (xs_read_stream_request_done(transport)) {
 630                 trace_xs_stream_read_request(transport);
 631                 transport->recv.copied = 0;
 632         }
 633         transport->recv.offset = 0;
 634         transport->recv.len = 0;
 635         return read;
 636 out_err:
 637         return ret != 0 ? ret : -ESHUTDOWN;
 638 }
 639
 640 static void xs_stream_data_receive(struct sock_xprt *transport)
 641 {
 642         size_t read = 0;
 643         ssize_t ret = 0;
 644
 645         mutex_lock(&transport->recv_mutex);
 646         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 647         if (transport->sock == NULL)
 648                 goto out;
 649         for (;;) {
 650                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 651                 if (ret < 0)
 652                         break;
 653                 read += ret;
 654                 cond_resched();
 655         }
 656 out:
 657         mutex_unlock(&transport->recv_mutex);
 658         trace_xs_stream_read_data(&transport->xprt, ret, read);
 659 }
 660
 661 static void xs_stream_data_receive_workfn(struct work_struct *work)
 662 {
 663         struct sock_xprt *transport =
 664                 container_of(work, struct sock_xprt, recv_worker);
 665         xs_stream_data_receive(transport);
 666 }
 667
 668 static void
 669 xs_stream_reset_connect(struct sock_xprt *transport)
 670 {
 671         transport->recv.offset = 0;
 672         transport->recv.len = 0;
 673         transport->recv.copied = 0;
 674         transport->xmit.offset = 0;
 675         transport->xprt.stat.connect_count++;
 676         transport->xprt.stat.connect_start = jiffies;
 677 }
 678
 679 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 680
 681 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 682 {
 683         struct msghdr msg = {
 684                 .msg_name       = addr,
 685                 .msg_namelen    = addrlen,
 686                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 687         };
 688         struct kvec iov = {
 689                 .iov_base       = vec->iov_base + base,
 690                 .iov_len        = vec->iov_len - base,
 691         };
 692
 693         if (iov.iov_len != 0)
 694                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 695         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 696 }
 697
 698 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p)
 699 {
 700         ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 701                         int offset, size_t size, int flags);
 702         struct page **ppage;
 703         unsigned int remainder;
 704         int err;
 705
 706         remainder = xdr->page_len - base;
 707         base += xdr->page_base;
 708         ppage = xdr->pages + (base >> PAGE_SHIFT);
 709         base &= ~PAGE_MASK;
 710         do_sendpage = sock->ops->sendpage;
 711         if (!zerocopy)
 712                 do_sendpage = sock_no_sendpage;
 713         for(;;) {
 714                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 715                 int flags = XS_SENDMSG_FLAGS;
 716
 717                 remainder -= len;
 718                 if (more)
 719                         flags |= MSG_MORE;
 720                 if (remainder != 0)
 721                         flags |= MSG_SENDPAGE_NOTLAST | MSG_MORE;
 722                 err = do_sendpage(sock, *ppage, base, len, flags);
 723                 if (remainder == 0 || err != len)
 724                         break;
 725                 *sent_p += err;
 726                 ppage++;
 727                 base = 0;
 728         }
 729         if (err > 0) {
 730                 *sent_p += err;
 731                 err = 0;
 732         }
 733         return err;
 734 }
 735
 736 /**
 737  * xs_sendpages - write pages directly to a socket
 738  * @sock: socket to send on
 739  * @addr: UDP only -- address of destination
 740  * @addrlen: UDP only -- length of destination address
 741  * @xdr: buffer containing this request
 742  * @base: starting position in the buffer
 743  * @zerocopy: true if it is safe to use sendpage()
 744  * @sent_p: return the total number of bytes successfully queued for sending
 745  *
 746  */
 747 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 748 {
 749         unsigned int remainder = xdr->len - base;
 750         int err = 0;
 751         int sent = 0;
 752
 753         if (unlikely(!sock))
 754                 return -ENOTSOCK;
 755
 756         if (base != 0) {
 757                 addr = NULL;
 758                 addrlen = 0;
 759         }
 760
 761         if (base < xdr->head[0].iov_len || addr != NULL) {
 762                 unsigned int len = xdr->head[0].iov_len - base;
 763                 remainder -= len;
 764                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 765                 if (remainder == 0 || err != len)
 766                         goto out;
 767                 *sent_p += err;
 768                 base = 0;
 769         } else
 770                 base -= xdr->head[0].iov_len;
 771
 772         if (base < xdr->page_len) {
 773                 unsigned int len = xdr->page_len - base;
 774                 remainder -= len;
 775                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 776                 *sent_p += sent;
 777                 if (remainder == 0 || sent != len)
 778                         goto out;
 779                 base = 0;
 780         } else
 781                 base -= xdr->page_len;
 782
 783         if (base >= xdr->tail[0].iov_len)
 784                 return 0;
 785         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 786 out:
 787         if (err > 0) {
 788                 *sent_p += err;
 789                 err = 0;
 790         }
 791         return err;
 792 }
 793
 794 /**
 795  * xs_nospace - handle transmit was incomplete
 796  * @req: pointer to RPC request
 797  *
 798  */
 799 static int xs_nospace(struct rpc_rqst *req)
 800 {
 801         struct rpc_xprt *xprt = req->rq_xprt;
 802         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 803         struct sock *sk = transport->inet;
 804         int ret = -EAGAIN;
 805
 806         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 807                         req->rq_task->tk_pid,
 808                         req->rq_slen - transport->xmit.offset,
 809                         req->rq_slen);
 810
 811         /* Protect against races with write_space */
 812         spin_lock_bh(&xprt->transport_lock);
 813
 814         /* Don't race with disconnect */
 815         if (xprt_connected(xprt)) {
 816                 /* wait for more buffer space */
 817                 sk->sk_write_pending++;
 818                 xprt_wait_for_buffer_space(xprt);
 819         } else
 820                 ret = -ENOTCONN;
 821
 822         spin_unlock_bh(&xprt->transport_lock);
 823
 824         /* Race breaker in case memory is freed before above code is called */
 825         if (ret == -EAGAIN) {
 826                 struct socket_wq *wq;
 827
 828                 rcu_read_lock();
 829                 wq = rcu_dereference(sk->sk_wq);
 830                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 831                 rcu_read_unlock();
 832
 833                 sk->sk_write_space(sk);
 834         }
 835         return ret;
 836 }
 837
 838 static void
 839 xs_stream_prepare_request(struct rpc_rqst *req)
 840 {
 841         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_NOIO);
 842 }
 843
 844 /*
 845  * Determine if the previous message in the stream was aborted before it
 846  * could complete transmission.
 847  */
 848 static bool
 849 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 850 {
 851         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 852 }
 853
 854 /*
 855  * Construct a stream transport record marker in @buf.
 856  */
 857 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 858 {
 859         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 860         rpc_fraghdr *base = buf->head[0].iov_base;
 861         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 862 }
 863
 864 /**
 865  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 866  * @req: pointer to RPC request
 867  *
 868  * Return values:
 869  *        0:    The request has been sent
 870  *   EAGAIN:    The socket was blocked, please call again later to
 871  *              complete the request
 872  * ENOTCONN:    Caller needs to invoke connect logic then call again
 873  *    other:    Some other error occured, the request was not sent
 874  */
 875 static int xs_local_send_request(struct rpc_rqst *req)
 876 {
 877         struct rpc_xprt *xprt = req->rq_xprt;
 878         struct sock_xprt *transport =
 879                                 container_of(xprt, struct sock_xprt, xprt);
 880         struct xdr_buf *xdr = &req->rq_snd_buf;
 881         int status;
 882         int sent = 0;
 883
 884         /* Close the stream if the previous transmission was incomplete */
 885         if (xs_send_request_was_aborted(transport, req)) {
 886                 xs_close(xprt);
 887                 return -ENOTCONN;
 888         }
 889
 890         xs_encode_stream_record_marker(&req->rq_snd_buf);
 891
 892         xs_pktdump("packet data:",
 893                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 894
 895         req->rq_xtime = ktime_get();
 896         status = xs_sendpages(transport->sock, NULL, 0, xdr,
 897                               transport->xmit.offset,
 898                               true, &sent);
 899         dprintk("RPC:       %s(%u) = %d\n",
 900                         __func__, xdr->len - transport->xmit.offset, status);
 901
 902         if (status == -EAGAIN && sock_writeable(transport->inet))
 903                 status = -ENOBUFS;
 904
 905         if (likely(sent > 0) || status == 0) {
 906                 transport->xmit.offset += sent;
 907                 req->rq_bytes_sent = transport->xmit.offset;
 908                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 909                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 910                         req->rq_bytes_sent = 0;
 911                         transport->xmit.offset = 0;
 912                         return 0;
 913                 }
 914                 status = -EAGAIN;
 915         }
 916
 917         switch (status) {
 918         case -ENOBUFS:
 919                 break;
 920         case -EAGAIN:
 921                 status = xs_nospace(req);
 922                 break;
 923         default:
 924                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 925                         -status);
 926                 /* fall through */
 927         case -EPIPE:
 928                 xs_close(xprt);
 929                 status = -ENOTCONN;
 930         }
 931
 932         return status;
 933 }
 934
 935 /**
 936  * xs_udp_send_request - write an RPC request to a UDP socket
 937  * @req: pointer to RPC request
 938  *
 939  * Return values:
 940  *        0:    The request has been sent
 941  *   EAGAIN:    The socket was blocked, please call again later to
 942  *              complete the request
 943  * ENOTCONN:    Caller needs to invoke connect logic then call again
 944  *    other:    Some other error occurred, the request was not sent
 945  */
 946 static int xs_udp_send_request(struct rpc_rqst *req)
 947 {
 948         struct rpc_xprt *xprt = req->rq_xprt;
 949         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 950         struct xdr_buf *xdr = &req->rq_snd_buf;
 951         int sent = 0;
 952         int status;
 953
 954         xs_pktdump("packet data:",
 955                                 req->rq_svec->iov_base,
 956                                 req->rq_svec->iov_len);
 957
 958         if (!xprt_bound(xprt))
 959                 return -ENOTCONN;
 960
 961         if (!xprt_request_get_cong(xprt, req))
 962                 return -EBADSLT;
 963
 964         req->rq_xtime = ktime_get();
 965         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 966                               xdr, 0, true, &sent);
 967
 968         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 969                         xdr->len, status);
 970
 971         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 972         if (status == -EPERM)
 973                 goto process_status;
 974
 975         if (status == -EAGAIN && sock_writeable(transport->inet))
 976                 status = -ENOBUFS;
 977
 978         if (sent > 0 || status == 0) {
 979                 req->rq_xmit_bytes_sent += sent;
 980                 if (sent >= req->rq_slen)
 981                         return 0;
 982                 /* Still some bytes left; set up for a retry later. */
 983                 status = -EAGAIN;
 984         }
 985
 986 process_status:
 987         switch (status) {
 988         case -ENOTSOCK:
 989                 status = -ENOTCONN;
 990                 /* Should we call xs_close() here? */
 991                 break;
 992         case -EAGAIN:
 993                 status = xs_nospace(req);
 994                 break;
 995         case -ENETUNREACH:
 996         case -ENOBUFS:
 997         case -EPIPE:
 998         case -ECONNREFUSED:
 999         case -EPERM:
1000                 /* When the server has died, an ICMP port unreachable message
1001                  * prompts ECONNREFUSED. */
1002                 break;
1003         default:
1004                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1005                         -status);
1006         }
1007
1008         return status;
1009 }
1010
1011 /**
1012  * xs_tcp_send_request - write an RPC request to a TCP socket
1013  * @req: pointer to RPC request
1014  *
1015  * Return values:
1016  *        0:    The request has been sent
1017  *   EAGAIN:    The socket was blocked, please call again later to
1018  *              complete the request
1019  * ENOTCONN:    Caller needs to invoke connect logic then call again
1020  *    other:    Some other error occurred, the request was not sent
1021  *
1022  * XXX: In the case of soft timeouts, should we eventually give up
1023  *      if sendmsg is not able to make progress?
1024  */
1025 static int xs_tcp_send_request(struct rpc_rqst *req)
1026 {
1027         struct rpc_xprt *xprt = req->rq_xprt;
1028         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1029         struct xdr_buf *xdr = &req->rq_snd_buf;
1030         bool zerocopy = true;
1031         bool vm_wait = false;
1032         int status;
1033         int sent;
1034
1035         /* Close the stream if the previous transmission was incomplete */
1036         if (xs_send_request_was_aborted(transport, req)) {
1037                 if (transport->sock != NULL)
1038                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1039                 return -ENOTCONN;
1040         }
1041
1042         xs_encode_stream_record_marker(&req->rq_snd_buf);
1043
1044         xs_pktdump("packet data:",
1045                                 req->rq_svec->iov_base,
1046                                 req->rq_svec->iov_len);
1047         /* Don't use zero copy if this is a resend. If the RPC call
1048          * completes while the socket holds a reference to the pages,
1049          * then we may end up resending corrupted data.
1050          */
1051         if (req->rq_task->tk_flags & RPC_TASK_SENT)
1052                 zerocopy = false;
1053
1054         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1055                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1056
1057         /* Continue transmitting the packet/record. We must be careful
1058          * to cope with writespace callbacks arriving _after_ we have
1059          * called sendmsg(). */
1060         req->rq_xtime = ktime_get();
1061         while (1) {
1062                 sent = 0;
1063                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1064                                       transport->xmit.offset,
1065                                       zerocopy, &sent);
1066
1067                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1068                                 xdr->len - transport->xmit.offset, status);
1069
1070                 /* If we've sent the entire packet, immediately
1071                  * reset the count of bytes sent. */
1072                 transport->xmit.offset += sent;
1073                 req->rq_bytes_sent = transport->xmit.offset;
1074                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
1075                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1076                         req->rq_bytes_sent = 0;
1077                         transport->xmit.offset = 0;
1078                         return 0;
1079                 }
1080
1081                 WARN_ON_ONCE(sent == 0 && status == 0);
1082
1083                 if (status == -EAGAIN ) {
1084                         /*
1085                          * Return EAGAIN if we're sure we're hitting the
1086                          * socket send buffer limits.
1087                          */
1088                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1089                                 break;
1090                         /*
1091                          * Did we hit a memory allocation failure?
1092                          */
1093                         if (sent == 0) {
1094                                 status = -ENOBUFS;
1095                                 if (vm_wait)
1096                                         break;
1097                                 /* Retry, knowing now that we're below the
1098                                  * socket send buffer limit
1099                                  */
1100                                 vm_wait = true;
1101                         }
1102                         continue;
1103                 }
1104                 if (status < 0)
1105                         break;
1106                 vm_wait = false;
1107         }
1108
1109         switch (status) {
1110         case -ENOTSOCK:
1111                 status = -ENOTCONN;
1112                 /* Should we call xs_close() here? */
1113                 break;
1114         case -EAGAIN:
1115                 status = xs_nospace(req);
1116                 break;
1117         case -ECONNRESET:
1118         case -ECONNREFUSED:
1119         case -ENOTCONN:
1120         case -EADDRINUSE:
1121         case -ENOBUFS:
1122         case -EPIPE:
1123                 break;
1124         default:
1125                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1126                         -status);
1127         }
1128
1129         return status;
1130 }
1131
1132 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1133 {
1134         transport->old_data_ready = sk->sk_data_ready;
1135         transport->old_state_change = sk->sk_state_change;
1136         transport->old_write_space = sk->sk_write_space;
1137         transport->old_error_report = sk->sk_error_report;
1138 }
1139
1140 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1141 {
1142         sk->sk_data_ready = transport->old_data_ready;
1143         sk->sk_state_change = transport->old_state_change;
1144         sk->sk_write_space = transport->old_write_space;
1145         sk->sk_error_report = transport->old_error_report;
1146 }
1147
1148 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1149 {
1150         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1151
1152         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1153 }
1154
1155 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1156 {
1157         smp_mb__before_atomic();
1158         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1159         clear_bit(XPRT_CLOSING, &xprt->state);
1160         xs_sock_reset_state_flags(xprt);
1161         smp_mb__after_atomic();
1162 }
1163
1164 /**
1165  * xs_error_report - callback to handle TCP socket state errors
1166  * @sk: socket
1167  *
1168  * Note: we don't call sock_error() since there may be a rpc_task
1169  * using the socket, and so we don't want to clear sk->sk_err.
1170  */
1171 static void xs_error_report(struct sock *sk)
1172 {
1173         struct rpc_xprt *xprt;
1174         int err;
1175
1176         read_lock_bh(&sk->sk_callback_lock);
1177         if (!(xprt = xprt_from_sock(sk)))
1178                 goto out;
1179
1180         err = -sk->sk_err;
1181         if (err == 0)
1182                 goto out;
1183         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1184                         xprt, -err);
1185         trace_rpc_socket_error(xprt, sk->sk_socket, err);
1186         xprt_wake_pending_tasks(xprt, err);
1187  out:
1188         read_unlock_bh(&sk->sk_callback_lock);
1189 }
1190
1191 static void xs_reset_transport(struct sock_xprt *transport)
1192 {
1193         struct socket *sock = transport->sock;
1194         struct sock *sk = transport->inet;
1195         struct rpc_xprt *xprt = &transport->xprt;
1196
1197         if (sk == NULL)
1198                 return;
1199
1200         if (atomic_read(&transport->xprt.swapper))
1201                 sk_clear_memalloc(sk);
1202
1203         kernel_sock_shutdown(sock, SHUT_RDWR);
1204
1205         mutex_lock(&transport->recv_mutex);
1206         write_lock_bh(&sk->sk_callback_lock);
1207         transport->inet = NULL;
1208         transport->sock = NULL;
1209
1210         sk->sk_user_data = NULL;
1211
1212         xs_restore_old_callbacks(transport, sk);
1213         xprt_clear_connected(xprt);
1214         write_unlock_bh(&sk->sk_callback_lock);
1215         xs_sock_reset_connection_flags(xprt);
1216         mutex_unlock(&transport->recv_mutex);
1217
1218         trace_rpc_socket_close(xprt, sock);
1219         sock_release(sock);
1220 }
1221
1222 /**
1223  * xs_close - close a socket
1224  * @xprt: transport
1225  *
1226  * This is used when all requests are complete; ie, no DRC state remains
1227  * on the server we want to save.
1228  *
1229  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1230  * xs_reset_transport() zeroing the socket from underneath a writer.
1231  */
1232 static void xs_close(struct rpc_xprt *xprt)
1233 {
1234         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1235
1236         dprintk("RPC:       xs_close xprt %p\n", xprt);
1237
1238         xs_reset_transport(transport);
1239         xprt->reestablish_timeout = 0;
1240
1241         xprt_disconnect_done(xprt);
1242 }
1243
1244 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1245 {
1246         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1247                 xprt);
1248         xprt_disconnect_done(xprt);
1249 }
1250
1251 static void xs_xprt_free(struct rpc_xprt *xprt)
1252 {
1253         xs_free_peer_addresses(xprt);
1254         xprt_free(xprt);
1255 }
1256
1257 /**
1258  * xs_destroy - prepare to shutdown a transport
1259  * @xprt: doomed transport
1260  *
1261  */
1262 static void xs_destroy(struct rpc_xprt *xprt)
1263 {
1264         struct sock_xprt *transport = container_of(xprt,
1265                         struct sock_xprt, xprt);
1266         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1267
1268         cancel_delayed_work_sync(&transport->connect_worker);
1269         xs_close(xprt);
1270         cancel_work_sync(&transport->recv_worker);
1271         xs_xprt_free(xprt);
1272         module_put(THIS_MODULE);
1273 }
1274
1275 /**
1276  * xs_udp_data_read_skb - receive callback for UDP sockets
1277  * @xprt: transport
1278  * @sk: socket
1279  * @skb: skbuff
1280  *
1281  */
1282 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1283                 struct sock *sk,
1284                 struct sk_buff *skb)
1285 {
1286         struct rpc_task *task;
1287         struct rpc_rqst *rovr;
1288         int repsize, copied;
1289         u32 _xid;
1290         __be32 *xp;
1291
1292         repsize = skb->len;
1293         if (repsize < 4) {
1294                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1295                 return;
1296         }
1297
1298         /* Copy the XID from the skb... */
1299         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1300         if (xp == NULL)
1301                 return;
1302
1303         /* Look up and lock the request corresponding to the given XID */
1304         spin_lock(&xprt->queue_lock);
1305         rovr = xprt_lookup_rqst(xprt, *xp);
1306         if (!rovr)
1307                 goto out_unlock;
1308         xprt_pin_rqst(rovr);
1309         xprt_update_rtt(rovr->rq_task);
1310         spin_unlock(&xprt->queue_lock);
1311         task = rovr->rq_task;
1312
1313         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1314                 copied = repsize;
1315
1316         /* Suck it into the iovec, verify checksum if not done by hw. */
1317         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1318                 spin_lock(&xprt->queue_lock);
1319                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1320                 goto out_unpin;
1321         }
1322
1323
1324         spin_lock_bh(&xprt->transport_lock);
1325         xprt_adjust_cwnd(xprt, task, copied);
1326         spin_unlock_bh(&xprt->transport_lock);
1327         spin_lock(&xprt->queue_lock);
1328         xprt_complete_rqst(task, copied);
1329         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1330 out_unpin:
1331         xprt_unpin_rqst(rovr);
1332  out_unlock:
1333         spin_unlock(&xprt->queue_lock);
1334 }
1335
1336 static void xs_udp_data_receive(struct sock_xprt *transport)
1337 {
1338         struct sk_buff *skb;
1339         struct sock *sk;
1340         int err;
1341
1342         mutex_lock(&transport->recv_mutex);
1343         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1344         sk = transport->inet;
1345         if (sk == NULL)
1346                 goto out;
1347         for (;;) {
1348                 skb = skb_recv_udp(sk, 0, 1, &err);
1349                 if (skb == NULL)
1350                         break;
1351                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1352                 consume_skb(skb);
1353                 cond_resched();
1354         }
1355 out:
1356         mutex_unlock(&transport->recv_mutex);
1357 }
1358
1359 static void xs_udp_data_receive_workfn(struct work_struct *work)
1360 {
1361         struct sock_xprt *transport =
1362                 container_of(work, struct sock_xprt, recv_worker);
1363         xs_udp_data_receive(transport);
1364 }
1365
1366 /**
1367  * xs_data_ready - "data ready" callback for UDP sockets
1368  * @sk: socket with data to read
1369  *
1370  */
1371 static void xs_data_ready(struct sock *sk)
1372 {
1373         struct rpc_xprt *xprt;
1374
1375         read_lock_bh(&sk->sk_callback_lock);
1376         dprintk("RPC:       xs_data_ready...\n");
1377         xprt = xprt_from_sock(sk);
1378         if (xprt != NULL) {
1379                 struct sock_xprt *transport = container_of(xprt,
1380                                 struct sock_xprt, xprt);
1381                 transport->old_data_ready(sk);
1382                 /* Any data means we had a useful conversation, so
1383                  * then we don't need to delay the next reconnect
1384                  */
1385                 if (xprt->reestablish_timeout)
1386                         xprt->reestablish_timeout = 0;
1387                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1388                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1389         }
1390         read_unlock_bh(&sk->sk_callback_lock);
1391 }
1392
1393 /*
1394  * Helper function to force a TCP close if the server is sending
1395  * junk and/or it has put us in CLOSE_WAIT
1396  */
1397 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1398 {
1399         xprt_force_disconnect(xprt);
1400 }
1401
1402 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1403 static int xs_tcp_bc_up(struct svc_serv *serv, struct net *net)
1404 {
1405         int ret;
1406
1407         ret = svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
1408                               SVC_SOCK_ANONYMOUS);
1409         if (ret < 0)
1410                 return ret;
1411         return 0;
1412 }
1413
1414 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1415 {
1416         return PAGE_SIZE;
1417 }
1418 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1419
1420 /**
1421  * xs_tcp_state_change - callback to handle TCP socket state changes
1422  * @sk: socket whose state has changed
1423  *
1424  */
1425 static void xs_tcp_state_change(struct sock *sk)
1426 {
1427         struct rpc_xprt *xprt;
1428         struct sock_xprt *transport;
1429
1430         read_lock_bh(&sk->sk_callback_lock);
1431         if (!(xprt = xprt_from_sock(sk)))
1432                 goto out;
1433         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1434         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1435                         sk->sk_state, xprt_connected(xprt),
1436                         sock_flag(sk, SOCK_DEAD),
1437                         sock_flag(sk, SOCK_ZAPPED),
1438                         sk->sk_shutdown);
1439
1440         transport = container_of(xprt, struct sock_xprt, xprt);
1441         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1442         switch (sk->sk_state) {
1443         case TCP_ESTABLISHED:
1444                 spin_lock(&xprt->transport_lock);
1445                 if (!xprt_test_and_set_connected(xprt)) {
1446                         xprt->connect_cookie++;
1447                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1448                         xprt_clear_connecting(xprt);
1449
1450                         xprt->stat.connect_count++;
1451                         xprt->stat.connect_time += (long)jiffies -
1452                                                    xprt->stat.connect_start;
1453                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1454                 }
1455                 spin_unlock(&xprt->transport_lock);
1456                 break;
1457         case TCP_FIN_WAIT1:
1458                 /* The client initiated a shutdown of the socket */
1459                 xprt->connect_cookie++;
1460                 xprt->reestablish_timeout = 0;
1461                 set_bit(XPRT_CLOSING, &xprt->state);
1462                 smp_mb__before_atomic();
1463                 clear_bit(XPRT_CONNECTED, &xprt->state);
1464                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1465                 smp_mb__after_atomic();
1466                 break;
1467         case TCP_CLOSE_WAIT:
1468                 /* The server initiated a shutdown of the socket */
1469                 xprt->connect_cookie++;
1470                 clear_bit(XPRT_CONNECTED, &xprt->state);
1471                 xs_tcp_force_close(xprt);
1472                 /* fall through */
1473         case TCP_CLOSING:
1474                 /*
1475                  * If the server closed down the connection, make sure that
1476                  * we back off before reconnecting
1477                  */
1478                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1479                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1480                 break;
1481         case TCP_LAST_ACK:
1482                 set_bit(XPRT_CLOSING, &xprt->state);
1483                 smp_mb__before_atomic();
1484                 clear_bit(XPRT_CONNECTED, &xprt->state);
1485                 smp_mb__after_atomic();
1486                 break;
1487         case TCP_CLOSE:
1488                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1489                                         &transport->sock_state))
1490                         xprt_clear_connecting(xprt);
1491                 clear_bit(XPRT_CLOSING, &xprt->state);
1492                 if (sk->sk_err)
1493                         xprt_wake_pending_tasks(xprt, -sk->sk_err);
1494                 /* Trigger the socket release */
1495                 xs_tcp_force_close(xprt);
1496         }
1497  out:
1498         read_unlock_bh(&sk->sk_callback_lock);
1499 }
1500
1501 static void xs_write_space(struct sock *sk)
1502 {
1503         struct socket_wq *wq;
1504         struct rpc_xprt *xprt;
1505
1506         if (!sk->sk_socket)
1507                 return;
1508         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1509
1510         if (unlikely(!(xprt = xprt_from_sock(sk))))
1511                 return;
1512         rcu_read_lock();
1513         wq = rcu_dereference(sk->sk_wq);
1514         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1515                 goto out;
1516
1517         if (xprt_write_space(xprt))
1518                 sk->sk_write_pending--;
1519 out:
1520         rcu_read_unlock();
1521 }
1522
1523 /**
1524  * xs_udp_write_space - callback invoked when socket buffer space
1525  *                             becomes available
1526  * @sk: socket whose state has changed
1527  *
1528  * Called when more output buffer space is available for this socket.
1529  * We try not to wake our writers until they can make "significant"
1530  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1531  * with a bunch of small requests.
1532  */
1533 static void xs_udp_write_space(struct sock *sk)
1534 {
1535         read_lock_bh(&sk->sk_callback_lock);
1536
1537         /* from net/core/sock.c:sock_def_write_space */
1538         if (sock_writeable(sk))
1539                 xs_write_space(sk);
1540
1541         read_unlock_bh(&sk->sk_callback_lock);
1542 }
1543
1544 /**
1545  * xs_tcp_write_space - callback invoked when socket buffer space
1546  *                             becomes available
1547  * @sk: socket whose state has changed
1548  *
1549  * Called when more output buffer space is available for this socket.
1550  * We try not to wake our writers until they can make "significant"
1551  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1552  * with a bunch of small requests.
1553  */
1554 static void xs_tcp_write_space(struct sock *sk)
1555 {
1556         read_lock_bh(&sk->sk_callback_lock);
1557
1558         /* from net/core/stream.c:sk_stream_write_space */
1559         if (sk_stream_is_writeable(sk))
1560                 xs_write_space(sk);
1561
1562         read_unlock_bh(&sk->sk_callback_lock);
1563 }
1564
1565 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1566 {
1567         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1568         struct sock *sk = transport->inet;
1569
1570         if (transport->rcvsize) {
1571                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1572                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1573         }
1574         if (transport->sndsize) {
1575                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1576                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1577                 sk->sk_write_space(sk);
1578         }
1579 }
1580
1581 /**
1582  * xs_udp_set_buffer_size - set send and receive limits
1583  * @xprt: generic transport
1584  * @sndsize: requested size of send buffer, in bytes
1585  * @rcvsize: requested size of receive buffer, in bytes
1586  *
1587  * Set socket send and receive buffer size limits.
1588  */
1589 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1590 {
1591         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1592
1593         transport->sndsize = 0;
1594         if (sndsize)
1595                 transport->sndsize = sndsize + 1024;
1596         transport->rcvsize = 0;
1597         if (rcvsize)
1598                 transport->rcvsize = rcvsize + 1024;
1599
1600         xs_udp_do_set_buffer_size(xprt);
1601 }
1602
1603 /**
1604  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1605  * @task: task that timed out
1606  *
1607  * Adjust the congestion window after a retransmit timeout has occurred.
1608  */
1609 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1610 {
1611         spin_lock_bh(&xprt->transport_lock);
1612         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1613         spin_unlock_bh(&xprt->transport_lock);
1614 }
1615
1616 static int xs_get_random_port(void)
1617 {
1618         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1619         unsigned short range;
1620         unsigned short rand;
1621
1622         if (max < min)
1623                 return -EADDRINUSE;
1624         range = max - min + 1;
1625         rand = (unsigned short) prandom_u32() % range;
1626         return rand + min;
1627 }
1628
1629 /**
1630  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1631  * @sock: socket
1632  *
1633  * Note that this function has to be called on all sockets that share the
1634  * same port, and it must be called before binding.
1635  */
1636 static void xs_sock_set_reuseport(struct socket *sock)
1637 {
1638         int opt = 1;
1639
1640         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1641                         (char *)&opt, sizeof(opt));
1642 }
1643
1644 static unsigned short xs_sock_getport(struct socket *sock)
1645 {
1646         struct sockaddr_storage buf;
1647         unsigned short port = 0;
1648
1649         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1650                 goto out;
1651         switch (buf.ss_family) {
1652         case AF_INET6:
1653                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1654                 break;
1655         case AF_INET:
1656                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1657         }
1658 out:
1659         return port;
1660 }
1661
1662 /**
1663  * xs_set_port - reset the port number in the remote endpoint address
1664  * @xprt: generic transport
1665  * @port: new port number
1666  *
1667  */
1668 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1669 {
1670         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1671
1672         rpc_set_port(xs_addr(xprt), port);
1673         xs_update_peer_port(xprt);
1674 }
1675
1676 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1677 {
1678         if (transport->srcport == 0)
1679                 transport->srcport = xs_sock_getport(sock);
1680 }
1681
1682 static int xs_get_srcport(struct sock_xprt *transport)
1683 {
1684         int port = transport->srcport;
1685
1686         if (port == 0 && transport->xprt.resvport)
1687                 port = xs_get_random_port();
1688         return port;
1689 }
1690
1691 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1692 {
1693         if (transport->srcport != 0)
1694                 transport->srcport = 0;
1695         if (!transport->xprt.resvport)
1696                 return 0;
1697         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1698                 return xprt_max_resvport;
1699         return --port;
1700 }
1701 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1702 {
1703         struct sockaddr_storage myaddr;
1704         int err, nloop = 0;
1705         int port = xs_get_srcport(transport);
1706         unsigned short last;
1707
1708         /*
1709          * If we are asking for any ephemeral port (i.e. port == 0 &&
1710          * transport->xprt.resvport == 0), don't bind.  Let the local
1711          * port selection happen implicitly when the socket is used
1712          * (for example at connect time).
1713          *
1714          * This ensures that we can continue to establish TCP
1715          * connections even when all local ephemeral ports are already
1716          * a part of some TCP connection.  This makes no difference
1717          * for UDP sockets, but also doens't harm them.
1718          *
1719          * If we're asking for any reserved port (i.e. port == 0 &&
1720          * transport->xprt.resvport == 1) xs_get_srcport above will
1721          * ensure that port is non-zero and we will bind as needed.
1722          */
1723         if (port <= 0)
1724                 return port;
1725
1726         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1727         do {
1728                 rpc_set_port((struct sockaddr *)&myaddr, port);
1729                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1730                                 transport->xprt.addrlen);
1731                 if (err == 0) {
1732                         transport->srcport = port;
1733                         break;
1734                 }
1735                 last = port;
1736                 port = xs_next_srcport(transport, port);
1737                 if (port > last)
1738                         nloop++;
1739         } while (err == -EADDRINUSE && nloop != 2);
1740
1741         if (myaddr.ss_family == AF_INET)
1742                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1743                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1744                                 port, err ? "failed" : "ok", err);
1745         else
1746                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1747                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1748                                 port, err ? "failed" : "ok", err);
1749         return err;
1750 }
1751
1752 /*
1753  * We don't support autobind on AF_LOCAL sockets
1754  */
1755 static void xs_local_rpcbind(struct rpc_task *task)
1756 {
1757         xprt_set_bound(task->tk_xprt);
1758 }
1759
1760 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1761 {
1762 }
1763
1764 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1765 static struct lock_class_key xs_key[2];
1766 static struct lock_class_key xs_slock_key[2];
1767
1768 static inline void xs_reclassify_socketu(struct socket *sock)
1769 {
1770         struct sock *sk = sock->sk;
1771
1772         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1773                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1774 }
1775
1776 static inline void xs_reclassify_socket4(struct socket *sock)
1777 {
1778         struct sock *sk = sock->sk;
1779
1780         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1781                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1782 }
1783
1784 static inline void xs_reclassify_socket6(struct socket *sock)
1785 {
1786         struct sock *sk = sock->sk;
1787
1788         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1789                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1790 }
1791
1792 static inline void xs_reclassify_socket(int family, struct socket *sock)
1793 {
1794         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1795                 return;
1796
1797         switch (family) {
1798         case AF_LOCAL:
1799                 xs_reclassify_socketu(sock);
1800                 break;
1801         case AF_INET:
1802                 xs_reclassify_socket4(sock);
1803                 break;
1804         case AF_INET6:
1805                 xs_reclassify_socket6(sock);
1806                 break;
1807         }
1808 }
1809 #else
1810 static inline void xs_reclassify_socket(int family, struct socket *sock)
1811 {
1812 }
1813 #endif
1814
1815 static void xs_dummy_setup_socket(struct work_struct *work)
1816 {
1817 }
1818
1819 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1820                 struct sock_xprt *transport, int family, int type,
1821                 int protocol, bool reuseport)
1822 {
1823         struct socket *sock;
1824         int err;
1825
1826         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1827         if (err < 0) {
1828                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1829                                 protocol, -err);
1830                 goto out;
1831         }
1832         xs_reclassify_socket(family, sock);
1833
1834         if (reuseport)
1835                 xs_sock_set_reuseport(sock);
1836
1837         err = xs_bind(transport, sock);
1838         if (err) {
1839                 sock_release(sock);
1840                 goto out;
1841         }
1842
1843         return sock;
1844 out:
1845         return ERR_PTR(err);
1846 }
1847
1848 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1849                                       struct socket *sock)
1850 {
1851         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1852                                                                         xprt);
1853
1854         if (!transport->inet) {
1855                 struct sock *sk = sock->sk;
1856
1857                 write_lock_bh(&sk->sk_callback_lock);
1858
1859                 xs_save_old_callbacks(transport, sk);
1860
1861                 sk->sk_user_data = xprt;
1862                 sk->sk_data_ready = xs_data_ready;
1863                 sk->sk_write_space = xs_udp_write_space;
1864                 sock_set_flag(sk, SOCK_FASYNC);
1865                 sk->sk_error_report = xs_error_report;
1866                 sk->sk_allocation = GFP_NOIO;
1867
1868                 xprt_clear_connected(xprt);
1869
1870                 /* Reset to new socket */
1871                 transport->sock = sock;
1872                 transport->inet = sk;
1873
1874                 write_unlock_bh(&sk->sk_callback_lock);
1875         }
1876
1877         xs_stream_reset_connect(transport);
1878
1879         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1880 }
1881
1882 /**
1883  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1884  * @transport: socket transport to connect
1885  */
1886 static int xs_local_setup_socket(struct sock_xprt *transport)
1887 {
1888         struct rpc_xprt *xprt = &transport->xprt;
1889         struct socket *sock;
1890         int status = -EIO;
1891
1892         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1893                                         SOCK_STREAM, 0, &sock, 1);
1894         if (status < 0) {
1895                 dprintk("RPC:       can't create AF_LOCAL "
1896                         "transport socket (%d).\n", -status);
1897                 goto out;
1898         }
1899         xs_reclassify_socket(AF_LOCAL, sock);
1900
1901         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1902                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1903
1904         status = xs_local_finish_connecting(xprt, sock);
1905         trace_rpc_socket_connect(xprt, sock, status);
1906         switch (status) {
1907         case 0:
1908                 dprintk("RPC:       xprt %p connected to %s\n",
1909                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1910                 xprt->stat.connect_count++;
1911                 xprt->stat.connect_time += (long)jiffies -
1912                                            xprt->stat.connect_start;
1913                 xprt_set_connected(xprt);
1914         case -ENOBUFS:
1915                 break;
1916         case -ENOENT:
1917                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1918                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1919                 break;
1920         case -ECONNREFUSED:
1921                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1922                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1923                 break;
1924         default:
1925                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1926                                 __func__, -status,
1927                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1928         }
1929
1930 out:
1931         xprt_clear_connecting(xprt);
1932         xprt_wake_pending_tasks(xprt, status);
1933         return status;
1934 }
1935
1936 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1937 {
1938         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1939         int ret;
1940
1941          if (RPC_IS_ASYNC(task)) {
1942                 /*
1943                  * We want the AF_LOCAL connect to be resolved in the
1944                  * filesystem namespace of the process making the rpc
1945                  * call.  Thus we connect synchronously.
1946                  *
1947                  * If we want to support asynchronous AF_LOCAL calls,
1948                  * we'll need to figure out how to pass a namespace to
1949                  * connect.
1950                  */
1951                 rpc_exit(task, -ENOTCONN);
1952                 return;
1953         }
1954         ret = xs_local_setup_socket(transport);
1955         if (ret && !RPC_IS_SOFTCONN(task))
1956                 msleep_interruptible(15000);
1957 }
1958
1959 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1960 /*
1961  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1962  * know that we have exclusive access to the socket), to guard against
1963  * races with xs_reset_transport.
1964  */
1965 static void xs_set_memalloc(struct rpc_xprt *xprt)
1966 {
1967         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1968                         xprt);
1969
1970         /*
1971          * If there's no sock, then we have nothing to set. The
1972          * reconnecting process will get it for us.
1973          */
1974         if (!transport->inet)
1975                 return;
1976         if (atomic_read(&xprt->swapper))
1977                 sk_set_memalloc(transport->inet);
1978 }
1979
1980 /**
1981  * xs_enable_swap - Tag this transport as being used for swap.
1982  * @xprt: transport to tag
1983  *
1984  * Take a reference to this transport on behalf of the rpc_clnt, and
1985  * optionally mark it for swapping if it wasn't already.
1986  */
1987 static int
1988 xs_enable_swap(struct rpc_xprt *xprt)
1989 {
1990         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1991
1992         if (atomic_inc_return(&xprt->swapper) != 1)
1993                 return 0;
1994         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1995                 return -ERESTARTSYS;
1996         if (xs->inet)
1997                 sk_set_memalloc(xs->inet);
1998         xprt_release_xprt(xprt, NULL);
1999         return 0;
2000 }
2001
2002 /**
2003  * xs_disable_swap - Untag this transport as being used for swap.
2004  * @xprt: transport to tag
2005  *
2006  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2007  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2008  */
2009 static void
2010 xs_disable_swap(struct rpc_xprt *xprt)
2011 {
2012         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2013
2014         if (!atomic_dec_and_test(&xprt->swapper))
2015                 return;
2016         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2017                 return;
2018         if (xs->inet)
2019                 sk_clear_memalloc(xs->inet);
2020         xprt_release_xprt(xprt, NULL);
2021 }
2022 #else
2023 static void xs_set_memalloc(struct rpc_xprt *xprt)
2024 {
2025 }
2026
2027 static int
2028 xs_enable_swap(struct rpc_xprt *xprt)
2029 {
2030         return -EINVAL;
2031 }
2032
2033 static void
2034 xs_disable_swap(struct rpc_xprt *xprt)
2035 {
2036 }
2037 #endif
2038
2039 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2040 {
2041         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2042
2043         if (!transport->inet) {
2044                 struct sock *sk = sock->sk;
2045
2046                 write_lock_bh(&sk->sk_callback_lock);
2047
2048                 xs_save_old_callbacks(transport, sk);
2049
2050                 sk->sk_user_data = xprt;
2051                 sk->sk_data_ready = xs_data_ready;
2052                 sk->sk_write_space = xs_udp_write_space;
2053                 sock_set_flag(sk, SOCK_FASYNC);
2054                 sk->sk_allocation = GFP_NOIO;
2055
2056                 xprt_set_connected(xprt);
2057
2058                 /* Reset to new socket */
2059                 transport->sock = sock;
2060                 transport->inet = sk;
2061
2062                 xs_set_memalloc(xprt);
2063
2064                 write_unlock_bh(&sk->sk_callback_lock);
2065         }
2066         xs_udp_do_set_buffer_size(xprt);
2067
2068         xprt->stat.connect_start = jiffies;
2069 }
2070
2071 static void xs_udp_setup_socket(struct work_struct *work)
2072 {
2073         struct sock_xprt *transport =
2074                 container_of(work, struct sock_xprt, connect_worker.work);
2075         struct rpc_xprt *xprt = &transport->xprt;
2076         struct socket *sock;
2077         int status = -EIO;
2078
2079         sock = xs_create_sock(xprt, transport,
2080                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2081                         IPPROTO_UDP, false);
2082         if (IS_ERR(sock))
2083                 goto out;
2084
2085         dprintk("RPC:       worker connecting xprt %p via %s to "
2086                                 "%s (port %s)\n", xprt,
2087                         xprt->address_strings[RPC_DISPLAY_PROTO],
2088                         xprt->address_strings[RPC_DISPLAY_ADDR],
2089                         xprt->address_strings[RPC_DISPLAY_PORT]);
2090
2091         xs_udp_finish_connecting(xprt, sock);
2092         trace_rpc_socket_connect(xprt, sock, 0);
2093         status = 0;
2094 out:
2095         xprt_unlock_connect(xprt, transport);
2096         xprt_clear_connecting(xprt);
2097         xprt_wake_pending_tasks(xprt, status);
2098 }
2099
2100 /**
2101  * xs_tcp_shutdown - gracefully shut down a TCP socket
2102  * @xprt: transport
2103  *
2104  * Initiates a graceful shutdown of the TCP socket by calling the
2105  * equivalent of shutdown(SHUT_RDWR);
2106  */
2107 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2108 {
2109         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2110         struct socket *sock = transport->sock;
2111         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2112
2113         if (sock == NULL)
2114                 return;
2115         switch (skst) {
2116         default:
2117                 kernel_sock_shutdown(sock, SHUT_RDWR);
2118                 trace_rpc_socket_shutdown(xprt, sock);
2119                 break;
2120         case TCP_CLOSE:
2121         case TCP_TIME_WAIT:
2122                 xs_reset_transport(transport);
2123         }
2124 }
2125
2126 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2127                 struct socket *sock)
2128 {
2129         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2130         unsigned int keepidle;
2131         unsigned int keepcnt;
2132         unsigned int opt_on = 1;
2133         unsigned int timeo;
2134
2135         spin_lock_bh(&xprt->transport_lock);
2136         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2137         keepcnt = xprt->timeout->to_retries + 1;
2138         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2139                 (xprt->timeout->to_retries + 1);
2140         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2141         spin_unlock_bh(&xprt->transport_lock);
2142
2143         /* TCP Keepalive options */
2144         kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2145                         (char *)&opt_on, sizeof(opt_on));
2146         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2147                         (char *)&keepidle, sizeof(keepidle));
2148         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2149                         (char *)&keepidle, sizeof(keepidle));
2150         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2151                         (char *)&keepcnt, sizeof(keepcnt));
2152
2153         /* TCP user timeout (see RFC5482) */
2154         kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2155                         (char *)&timeo, sizeof(timeo));
2156 }
2157
2158 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2159                 unsigned long connect_timeout,
2160                 unsigned long reconnect_timeout)
2161 {
2162         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2163         struct rpc_timeout to;
2164         unsigned long initval;
2165
2166         spin_lock_bh(&xprt->transport_lock);
2167         if (reconnect_timeout < xprt->max_reconnect_timeout)
2168                 xprt->max_reconnect_timeout = reconnect_timeout;
2169         if (connect_timeout < xprt->connect_timeout) {
2170                 memcpy(&to, xprt->timeout, sizeof(to));
2171                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2172                 /* Arbitrary lower limit */
2173                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2174                         initval = XS_TCP_INIT_REEST_TO << 1;
2175                 to.to_initval = initval;
2176                 to.to_maxval = initval;
2177                 memcpy(&transport->tcp_timeout, &to,
2178                                 sizeof(transport->tcp_timeout));
2179                 xprt->timeout = &transport->tcp_timeout;
2180                 xprt->connect_timeout = connect_timeout;
2181         }
2182         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2183         spin_unlock_bh(&xprt->transport_lock);
2184 }
2185
2186 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2187 {
2188         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2189         int ret = -ENOTCONN;
2190
2191         if (!transport->inet) {
2192                 struct sock *sk = sock->sk;
2193                 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2194
2195                 /* Avoid temporary address, they are bad for long-lived
2196                  * connections such as NFS mounts.
2197                  * RFC4941, section 3.6 suggests that:
2198                  *    Individual applications, which have specific
2199                  *    knowledge about the normal duration of connections,
2200                  *    MAY override this as appropriate.
2201                  */
2202                 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2203                                 (char *)&addr_pref, sizeof(addr_pref));
2204
2205                 xs_tcp_set_socket_timeouts(xprt, sock);
2206
2207                 write_lock_bh(&sk->sk_callback_lock);
2208
2209                 xs_save_old_callbacks(transport, sk);
2210
2211                 sk->sk_user_data = xprt;
2212                 sk->sk_data_ready = xs_data_ready;
2213                 sk->sk_state_change = xs_tcp_state_change;
2214                 sk->sk_write_space = xs_tcp_write_space;
2215                 sock_set_flag(sk, SOCK_FASYNC);
2216                 sk->sk_error_report = xs_error_report;
2217                 sk->sk_allocation = GFP_NOIO;
2218
2219                 /* socket options */
2220                 sock_reset_flag(sk, SOCK_LINGER);
2221                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2222
2223                 xprt_clear_connected(xprt);
2224
2225                 /* Reset to new socket */
2226                 transport->sock = sock;
2227                 transport->inet = sk;
2228
2229                 write_unlock_bh(&sk->sk_callback_lock);
2230         }
2231
2232         if (!xprt_bound(xprt))
2233                 goto out;
2234
2235         xs_set_memalloc(xprt);
2236
2237         /* Reset TCP record info */
2238         xs_stream_reset_connect(transport);
2239
2240         /* Tell the socket layer to start connecting... */
2241         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2242         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2243         switch (ret) {
2244         case 0:
2245                 xs_set_srcport(transport, sock);
2246                 /* fall through */
2247         case -EINPROGRESS:
2248                 /* SYN_SENT! */
2249                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2250                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2251                 break;
2252         case -EADDRNOTAVAIL:
2253                 /* Source port number is unavailable. Try a new one! */
2254                 transport->srcport = 0;
2255         }
2256 out:
2257         return ret;
2258 }
2259
2260 /**
2261  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2262  *
2263  * Invoked by a work queue tasklet.
2264  */
2265 static void xs_tcp_setup_socket(struct work_struct *work)
2266 {
2267         struct sock_xprt *transport =
2268                 container_of(work, struct sock_xprt, connect_worker.work);
2269         struct socket *sock = transport->sock;
2270         struct rpc_xprt *xprt = &transport->xprt;
2271         int status = -EIO;
2272
2273         if (!sock) {
2274                 sock = xs_create_sock(xprt, transport,
2275                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2276                                 IPPROTO_TCP, true);
2277                 if (IS_ERR(sock)) {
2278                         status = PTR_ERR(sock);
2279                         goto out;
2280                 }
2281         }
2282
2283         dprintk("RPC:       worker connecting xprt %p via %s to "
2284                                 "%s (port %s)\n", xprt,
2285                         xprt->address_strings[RPC_DISPLAY_PROTO],
2286                         xprt->address_strings[RPC_DISPLAY_ADDR],
2287                         xprt->address_strings[RPC_DISPLAY_PORT]);
2288
2289         status = xs_tcp_finish_connecting(xprt, sock);
2290         trace_rpc_socket_connect(xprt, sock, status);
2291         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2292                         xprt, -status, xprt_connected(xprt),
2293                         sock->sk->sk_state);
2294         switch (status) {
2295         default:
2296                 printk("%s: connect returned unhandled error %d\n",
2297                         __func__, status);
2298                 /* fall through */
2299         case -EADDRNOTAVAIL:
2300                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2301                  * and retry
2302                  */
2303                 xs_tcp_force_close(xprt);
2304                 break;
2305         case 0:
2306         case -EINPROGRESS:
2307         case -EALREADY:
2308                 xprt_unlock_connect(xprt, transport);
2309                 return;
2310         case -EINVAL:
2311                 /* Happens, for instance, if the user specified a link
2312                  * local IPv6 address without a scope-id.
2313                  */
2314         case -ECONNREFUSED:
2315         case -ECONNRESET:
2316         case -ENETDOWN:
2317         case -ENETUNREACH:
2318         case -EHOSTUNREACH:
2319         case -EADDRINUSE:
2320         case -ENOBUFS:
2321                 /*
2322                  * xs_tcp_force_close() wakes tasks with -EIO.
2323                  * We need to wake them first to ensure the
2324                  * correct error code.
2325                  */
2326                 xprt_wake_pending_tasks(xprt, status);
2327                 xs_tcp_force_close(xprt);
2328                 goto out;
2329         }
2330         status = -EAGAIN;
2331 out:
2332         xprt_unlock_connect(xprt, transport);
2333         xprt_clear_connecting(xprt);
2334         xprt_wake_pending_tasks(xprt, status);
2335 }
2336
2337 static unsigned long xs_reconnect_delay(const struct rpc_xprt *xprt)
2338 {
2339         unsigned long start, now = jiffies;
2340
2341         start = xprt->stat.connect_start + xprt->reestablish_timeout;
2342         if (time_after(start, now))
2343                 return start - now;
2344         return 0;
2345 }
2346
2347 static void xs_reconnect_backoff(struct rpc_xprt *xprt)
2348 {
2349         xprt->reestablish_timeout <<= 1;
2350         if (xprt->reestablish_timeout > xprt->max_reconnect_timeout)
2351                 xprt->reestablish_timeout = xprt->max_reconnect_timeout;
2352         if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2353                 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2354 }
2355
2356 /**
2357  * xs_connect - connect a socket to a remote endpoint
2358  * @xprt: pointer to transport structure
2359  * @task: address of RPC task that manages state of connect request
2360  *
2361  * TCP: If the remote end dropped the connection, delay reconnecting.
2362  *
2363  * UDP socket connects are synchronous, but we use a work queue anyway
2364  * to guarantee that even unprivileged user processes can set up a
2365  * socket on a privileged port.
2366  *
2367  * If a UDP socket connect fails, the delay behavior here prevents
2368  * retry floods (hard mounts).
2369  */
2370 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2371 {
2372         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2373         unsigned long delay = 0;
2374
2375         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2376
2377         if (transport->sock != NULL) {
2378                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2379                                 "seconds\n",
2380                                 xprt, xprt->reestablish_timeout / HZ);
2381
2382                 /* Start by resetting any existing state */
2383                 xs_reset_transport(transport);
2384
2385                 delay = xs_reconnect_delay(xprt);
2386                 xs_reconnect_backoff(xprt);
2387
2388         } else
2389                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2390
2391         queue_delayed_work(xprtiod_workqueue,
2392                         &transport->connect_worker,
2393                         delay);
2394 }
2395
2396 /**
2397  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2398  * @xprt: rpc_xprt struct containing statistics
2399  * @seq: output file
2400  *
2401  */
2402 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2403 {
2404         long idle_time = 0;
2405
2406         if (xprt_connected(xprt))
2407                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2408
2409         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2410                         "%llu %llu %lu %llu %llu\n",
2411                         xprt->stat.bind_count,
2412                         xprt->stat.connect_count,
2413                         xprt->stat.connect_time / HZ,
2414                         idle_time,
2415                         xprt->stat.sends,
2416                         xprt->stat.recvs,
2417                         xprt->stat.bad_xids,
2418                         xprt->stat.req_u,
2419                         xprt->stat.bklog_u,
2420                         xprt->stat.max_slots,
2421                         xprt->stat.sending_u,
2422                         xprt->stat.pending_u);
2423 }
2424
2425 /**
2426  * xs_udp_print_stats - display UDP socket-specifc stats
2427  * @xprt: rpc_xprt struct containing statistics
2428  * @seq: output file
2429  *
2430  */
2431 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2432 {
2433         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2434
2435         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2436                         "%lu %llu %llu\n",
2437                         transport->srcport,
2438                         xprt->stat.bind_count,
2439                         xprt->stat.sends,
2440                         xprt->stat.recvs,
2441                         xprt->stat.bad_xids,
2442                         xprt->stat.req_u,
2443                         xprt->stat.bklog_u,
2444                         xprt->stat.max_slots,
2445                         xprt->stat.sending_u,
2446                         xprt->stat.pending_u);
2447 }
2448
2449 /**
2450  * xs_tcp_print_stats - display TCP socket-specifc stats
2451  * @xprt: rpc_xprt struct containing statistics
2452  * @seq: output file
2453  *
2454  */
2455 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2456 {
2457         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2458         long idle_time = 0;
2459
2460         if (xprt_connected(xprt))
2461                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2462
2463         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2464                         "%llu %llu %lu %llu %llu\n",
2465                         transport->srcport,
2466                         xprt->stat.bind_count,
2467                         xprt->stat.connect_count,
2468                         xprt->stat.connect_time / HZ,
2469                         idle_time,
2470                         xprt->stat.sends,
2471                         xprt->stat.recvs,
2472                         xprt->stat.bad_xids,
2473                         xprt->stat.req_u,
2474                         xprt->stat.bklog_u,
2475                         xprt->stat.max_slots,
2476                         xprt->stat.sending_u,
2477                         xprt->stat.pending_u);
2478 }
2479
2480 /*
2481  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2482  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2483  * to use the server side send routines.
2484  */
2485 static int bc_malloc(struct rpc_task *task)
2486 {
2487         struct rpc_rqst *rqst = task->tk_rqstp;
2488         size_t size = rqst->rq_callsize;
2489         struct page *page;
2490         struct rpc_buffer *buf;
2491
2492         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2493                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2494                           size);
2495                 return -EINVAL;
2496         }
2497
2498         page = alloc_page(GFP_KERNEL);
2499         if (!page)
2500                 return -ENOMEM;
2501
2502         buf = page_address(page);
2503         buf->len = PAGE_SIZE;
2504
2505         rqst->rq_buffer = buf->data;
2506         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2507         return 0;
2508 }
2509
2510 /*
2511  * Free the space allocated in the bc_alloc routine
2512  */
2513 static void bc_free(struct rpc_task *task)
2514 {
2515         void *buffer = task->tk_rqstp->rq_buffer;
2516         struct rpc_buffer *buf;
2517
2518         buf = container_of(buffer, struct rpc_buffer, data);
2519         free_page((unsigned long)buf);
2520 }
2521
2522 /*
2523  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2524  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2525  */
2526 static int bc_sendto(struct rpc_rqst *req)
2527 {
2528         int len;
2529         struct xdr_buf *xbufp = &req->rq_snd_buf;
2530         struct rpc_xprt *xprt = req->rq_xprt;
2531         struct sock_xprt *transport =
2532                                 container_of(xprt, struct sock_xprt, xprt);
2533         struct socket *sock = transport->sock;
2534         unsigned long headoff;
2535         unsigned long tailoff;
2536
2537         xs_encode_stream_record_marker(xbufp);
2538
2539         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2540         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2541         len = svc_send_common(sock, xbufp,
2542                               virt_to_page(xbufp->head[0].iov_base), headoff,
2543                               xbufp->tail[0].iov_base, tailoff);
2544
2545         if (len != xbufp->len) {
2546                 printk(KERN_NOTICE "Error sending entire callback!\n");
2547                 len = -EAGAIN;
2548         }
2549
2550         return len;
2551 }
2552
2553 /*
2554  * The send routine. Borrows from svc_send
2555  */
2556 static int bc_send_request(struct rpc_rqst *req)
2557 {
2558         struct svc_xprt *xprt;
2559         int len;
2560
2561         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2562         /*
2563          * Get the server socket associated with this callback xprt
2564          */
2565         xprt = req->rq_xprt->bc_xprt;
2566
2567         /*
2568          * Grab the mutex to serialize data as the connection is shared
2569          * with the fore channel
2570          */
2571         mutex_lock(&xprt->xpt_mutex);
2572         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2573                 len = -ENOTCONN;
2574         else
2575                 len = bc_sendto(req);
2576         mutex_unlock(&xprt->xpt_mutex);
2577
2578         if (len > 0)
2579                 len = 0;
2580
2581         return len;
2582 }
2583
2584 /*
2585  * The close routine. Since this is client initiated, we do nothing
2586  */
2587
2588 static void bc_close(struct rpc_xprt *xprt)
2589 {
2590 }
2591
2592 /*
2593  * The xprt destroy routine. Again, because this connection is client
2594  * initiated, we do nothing
2595  */
2596
2597 static void bc_destroy(struct rpc_xprt *xprt)
2598 {
2599         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2600
2601         xs_xprt_free(xprt);
2602         module_put(THIS_MODULE);
2603 }
2604
2605 static const struct rpc_xprt_ops xs_local_ops = {
2606         .reserve_xprt           = xprt_reserve_xprt,
2607         .release_xprt           = xprt_release_xprt,
2608         .alloc_slot             = xprt_alloc_slot,
2609         .free_slot              = xprt_free_slot,
2610         .rpcbind                = xs_local_rpcbind,
2611         .set_port               = xs_local_set_port,
2612         .connect                = xs_local_connect,
2613         .buf_alloc              = rpc_malloc,
2614         .buf_free               = rpc_free,
2615         .prepare_request        = xs_stream_prepare_request,
2616         .send_request           = xs_local_send_request,
2617         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2618         .close                  = xs_close,
2619         .destroy                = xs_destroy,
2620         .print_stats            = xs_local_print_stats,
2621         .enable_swap            = xs_enable_swap,
2622         .disable_swap           = xs_disable_swap,
2623 };
2624
2625 static const struct rpc_xprt_ops xs_udp_ops = {
2626         .set_buffer_size        = xs_udp_set_buffer_size,
2627         .reserve_xprt           = xprt_reserve_xprt_cong,
2628         .release_xprt           = xprt_release_xprt_cong,
2629         .alloc_slot             = xprt_alloc_slot,
2630         .free_slot              = xprt_free_slot,
2631         .rpcbind                = rpcb_getport_async,
2632         .set_port               = xs_set_port,
2633         .connect                = xs_connect,
2634         .buf_alloc              = rpc_malloc,
2635         .buf_free               = rpc_free,
2636         .send_request           = xs_udp_send_request,
2637         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2638         .timer                  = xs_udp_timer,
2639         .release_request        = xprt_release_rqst_cong,
2640         .close                  = xs_close,
2641         .destroy                = xs_destroy,
2642         .print_stats            = xs_udp_print_stats,
2643         .enable_swap            = xs_enable_swap,
2644         .disable_swap           = xs_disable_swap,
2645         .inject_disconnect      = xs_inject_disconnect,
2646 };
2647
2648 static const struct rpc_xprt_ops xs_tcp_ops = {
2649         .reserve_xprt           = xprt_reserve_xprt,
2650         .release_xprt           = xprt_release_xprt,
2651         .alloc_slot             = xprt_alloc_slot,
2652         .free_slot              = xprt_free_slot,
2653         .rpcbind                = rpcb_getport_async,
2654         .set_port               = xs_set_port,
2655         .connect                = xs_connect,
2656         .buf_alloc              = rpc_malloc,
2657         .buf_free               = rpc_free,
2658         .prepare_request        = xs_stream_prepare_request,
2659         .send_request           = xs_tcp_send_request,
2660         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2661         .close                  = xs_tcp_shutdown,
2662         .destroy                = xs_destroy,
2663         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2664         .print_stats            = xs_tcp_print_stats,
2665         .enable_swap            = xs_enable_swap,
2666         .disable_swap           = xs_disable_swap,
2667         .inject_disconnect      = xs_inject_disconnect,
2668 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2669         .bc_setup               = xprt_setup_bc,
2670         .bc_up                  = xs_tcp_bc_up,
2671         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2672         .bc_free_rqst           = xprt_free_bc_rqst,
2673         .bc_destroy             = xprt_destroy_bc,
2674 #endif
2675 };
2676
2677 /*
2678  * The rpc_xprt_ops for the server backchannel
2679  */
2680
2681 static const struct rpc_xprt_ops bc_tcp_ops = {
2682         .reserve_xprt           = xprt_reserve_xprt,
2683         .release_xprt           = xprt_release_xprt,
2684         .alloc_slot             = xprt_alloc_slot,
2685         .free_slot              = xprt_free_slot,
2686         .buf_alloc              = bc_malloc,
2687         .buf_free               = bc_free,
2688         .send_request           = bc_send_request,
2689         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2690         .close                  = bc_close,
2691         .destroy                = bc_destroy,
2692         .print_stats            = xs_tcp_print_stats,
2693         .enable_swap            = xs_enable_swap,
2694         .disable_swap           = xs_disable_swap,
2695         .inject_disconnect      = xs_inject_disconnect,
2696 };
2697
2698 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2699 {
2700         static const struct sockaddr_in sin = {
2701                 .sin_family             = AF_INET,
2702                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2703         };
2704         static const struct sockaddr_in6 sin6 = {
2705                 .sin6_family            = AF_INET6,
2706                 .sin6_addr              = IN6ADDR_ANY_INIT,
2707         };
2708
2709         switch (family) {
2710         case AF_LOCAL:
2711                 break;
2712         case AF_INET:
2713                 memcpy(sap, &sin, sizeof(sin));
2714                 break;
2715         case AF_INET6:
2716                 memcpy(sap, &sin6, sizeof(sin6));
2717                 break;
2718         default:
2719                 dprintk("RPC:       %s: Bad address family\n", __func__);
2720                 return -EAFNOSUPPORT;
2721         }
2722         return 0;
2723 }
2724
2725 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2726                                       unsigned int slot_table_size,
2727                                       unsigned int max_slot_table_size)
2728 {
2729         struct rpc_xprt *xprt;
2730         struct sock_xprt *new;
2731
2732         if (args->addrlen > sizeof(xprt->addr)) {
2733                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2734                 return ERR_PTR(-EBADF);
2735         }
2736
2737         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2738                         max_slot_table_size);
2739         if (xprt == NULL) {
2740                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2741                                 "rpc_xprt\n");
2742                 return ERR_PTR(-ENOMEM);
2743         }
2744
2745         new = container_of(xprt, struct sock_xprt, xprt);
2746         mutex_init(&new->recv_mutex);
2747         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2748         xprt->addrlen = args->addrlen;
2749         if (args->srcaddr)
2750                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2751         else {
2752                 int err;
2753                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2754                                         (struct sockaddr *)&new->srcaddr);
2755                 if (err != 0) {
2756                         xprt_free(xprt);
2757                         return ERR_PTR(err);
2758                 }
2759         }
2760
2761         return xprt;
2762 }
2763
2764 static const struct rpc_timeout xs_local_default_timeout = {
2765         .to_initval = 10 * HZ,
2766         .to_maxval = 10 * HZ,
2767         .to_retries = 2,
2768 };
2769
2770 /**
2771  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2772  * @args: rpc transport creation arguments
2773  *
2774  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2775  */
2776 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2777 {
2778         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2779         struct sock_xprt *transport;
2780         struct rpc_xprt *xprt;
2781         struct rpc_xprt *ret;
2782
2783         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2784                         xprt_max_tcp_slot_table_entries);
2785         if (IS_ERR(xprt))
2786                 return xprt;
2787         transport = container_of(xprt, struct sock_xprt, xprt);
2788
2789         xprt->prot = 0;
2790         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2791         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2792
2793         xprt->bind_timeout = XS_BIND_TO;
2794         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2795         xprt->idle_timeout = XS_IDLE_DISC_TO;
2796
2797         xprt->ops = &xs_local_ops;
2798         xprt->timeout = &xs_local_default_timeout;
2799
2800         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2801         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2802
2803         switch (sun->sun_family) {
2804         case AF_LOCAL:
2805                 if (sun->sun_path[0] != '/') {
2806                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2807                                         sun->sun_path);
2808                         ret = ERR_PTR(-EINVAL);
2809                         goto out_err;
2810                 }
2811                 xprt_set_bound(xprt);
2812                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2813                 ret = ERR_PTR(xs_local_setup_socket(transport));
2814                 if (ret)
2815                         goto out_err;
2816                 break;
2817         default:
2818                 ret = ERR_PTR(-EAFNOSUPPORT);
2819                 goto out_err;
2820         }
2821
2822         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2823                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2824
2825         if (try_module_get(THIS_MODULE))
2826                 return xprt;
2827         ret = ERR_PTR(-EINVAL);
2828 out_err:
2829         xs_xprt_free(xprt);
2830         return ret;
2831 }
2832
2833 static const struct rpc_timeout xs_udp_default_timeout = {
2834         .to_initval = 5 * HZ,
2835         .to_maxval = 30 * HZ,
2836         .to_increment = 5 * HZ,
2837         .to_retries = 5,
2838 };
2839
2840 /**
2841  * xs_setup_udp - Set up transport to use a UDP socket
2842  * @args: rpc transport creation arguments
2843  *
2844  */
2845 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2846 {
2847         struct sockaddr *addr = args->dstaddr;
2848         struct rpc_xprt *xprt;
2849         struct sock_xprt *transport;
2850         struct rpc_xprt *ret;
2851
2852         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2853                         xprt_udp_slot_table_entries);
2854         if (IS_ERR(xprt))
2855                 return xprt;
2856         transport = container_of(xprt, struct sock_xprt, xprt);
2857
2858         xprt->prot = IPPROTO_UDP;
2859         xprt->tsh_size = 0;
2860         /* XXX: header size can vary due to auth type, IPv6, etc. */
2861         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2862
2863         xprt->bind_timeout = XS_BIND_TO;
2864         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2865         xprt->idle_timeout = XS_IDLE_DISC_TO;
2866
2867         xprt->ops = &xs_udp_ops;
2868
2869         xprt->timeout = &xs_udp_default_timeout;
2870
2871         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2872         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2873
2874         switch (addr->sa_family) {
2875         case AF_INET:
2876                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2877                         xprt_set_bound(xprt);
2878
2879                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2880                 break;
2881         case AF_INET6:
2882                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2883                         xprt_set_bound(xprt);
2884
2885                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2886                 break;
2887         default:
2888                 ret = ERR_PTR(-EAFNOSUPPORT);
2889                 goto out_err;
2890         }
2891
2892         if (xprt_bound(xprt))
2893                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2894                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2895                                 xprt->address_strings[RPC_DISPLAY_PORT],
2896                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2897         else
2898                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2899                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2900                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2901
2902         if (try_module_get(THIS_MODULE))
2903                 return xprt;
2904         ret = ERR_PTR(-EINVAL);
2905 out_err:
2906         xs_xprt_free(xprt);
2907         return ret;
2908 }
2909
2910 static const struct rpc_timeout xs_tcp_default_timeout = {
2911         .to_initval = 60 * HZ,
2912         .to_maxval = 60 * HZ,
2913         .to_retries = 2,
2914 };
2915
2916 /**
2917  * xs_setup_tcp - Set up transport to use a TCP socket
2918  * @args: rpc transport creation arguments
2919  *
2920  */
2921 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2922 {
2923         struct sockaddr *addr = args->dstaddr;
2924         struct rpc_xprt *xprt;
2925         struct sock_xprt *transport;
2926         struct rpc_xprt *ret;
2927         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2928
2929         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2930                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2931
2932         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2933                         max_slot_table_size);
2934         if (IS_ERR(xprt))
2935                 return xprt;
2936         transport = container_of(xprt, struct sock_xprt, xprt);
2937
2938         xprt->prot = IPPROTO_TCP;
2939         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2940         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2941
2942         xprt->bind_timeout = XS_BIND_TO;
2943         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2944         xprt->idle_timeout = XS_IDLE_DISC_TO;
2945
2946         xprt->ops = &xs_tcp_ops;
2947         xprt->timeout = &xs_tcp_default_timeout;
2948
2949         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2950         xprt->connect_timeout = xprt->timeout->to_initval *
2951                 (xprt->timeout->to_retries + 1);
2952
2953         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2954         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2955
2956         switch (addr->sa_family) {
2957         case AF_INET:
2958                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2959                         xprt_set_bound(xprt);
2960
2961                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2962                 break;
2963         case AF_INET6:
2964                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2965                         xprt_set_bound(xprt);
2966
2967                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2968                 break;
2969         default:
2970                 ret = ERR_PTR(-EAFNOSUPPORT);
2971                 goto out_err;
2972         }
2973
2974         if (xprt_bound(xprt))
2975                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2976                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2977                                 xprt->address_strings[RPC_DISPLAY_PORT],
2978                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2979         else
2980                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2981                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2982                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2983
2984         if (try_module_get(THIS_MODULE))
2985                 return xprt;
2986         ret = ERR_PTR(-EINVAL);
2987 out_err:
2988         xs_xprt_free(xprt);
2989         return ret;
2990 }
2991
2992 /**
2993  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2994  * @args: rpc transport creation arguments
2995  *
2996  */
2997 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2998 {
2999         struct sockaddr *addr = args->dstaddr;
3000         struct rpc_xprt *xprt;
3001         struct sock_xprt *transport;
3002         struct svc_sock *bc_sock;
3003         struct rpc_xprt *ret;
3004
3005         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3006                         xprt_tcp_slot_table_entries);
3007         if (IS_ERR(xprt))
3008                 return xprt;
3009         transport = container_of(xprt, struct sock_xprt, xprt);
3010
3011         xprt->prot = IPPROTO_TCP;
3012         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3013         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3014         xprt->timeout = &xs_tcp_default_timeout;
3015
3016         /* backchannel */
3017         xprt_set_bound(xprt);
3018         xprt->bind_timeout = 0;
3019         xprt->reestablish_timeout = 0;
3020         xprt->idle_timeout = 0;
3021
3022         xprt->ops = &bc_tcp_ops;
3023
3024         switch (addr->sa_family) {
3025         case AF_INET:
3026                 xs_format_peer_addresses(xprt, "tcp",
3027                                          RPCBIND_NETID_TCP);
3028                 break;
3029         case AF_INET6:
3030                 xs_format_peer_addresses(xprt, "tcp",
3031                                    RPCBIND_NETID_TCP6);
3032                 break;
3033         default:
3034                 ret = ERR_PTR(-EAFNOSUPPORT);
3035                 goto out_err;
3036         }
3037
3038         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3039                         xprt->address_strings[RPC_DISPLAY_ADDR],
3040                         xprt->address_strings[RPC_DISPLAY_PORT],
3041                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3042
3043         /*
3044          * Once we've associated a backchannel xprt with a connection,
3045          * we want to keep it around as long as the connection lasts,
3046          * in case we need to start using it for a backchannel again;
3047          * this reference won't be dropped until bc_xprt is destroyed.
3048          */
3049         xprt_get(xprt);
3050         args->bc_xprt->xpt_bc_xprt = xprt;
3051         xprt->bc_xprt = args->bc_xprt;
3052         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3053         transport->sock = bc_sock->sk_sock;
3054         transport->inet = bc_sock->sk_sk;
3055
3056         /*
3057          * Since we don't want connections for the backchannel, we set
3058          * the xprt status to connected
3059          */
3060         xprt_set_connected(xprt);
3061
3062         if (try_module_get(THIS_MODULE))
3063                 return xprt;
3064
3065         args->bc_xprt->xpt_bc_xprt = NULL;
3066         args->bc_xprt->xpt_bc_xps = NULL;
3067         xprt_put(xprt);
3068         ret = ERR_PTR(-EINVAL);
3069 out_err:
3070         xs_xprt_free(xprt);
3071         return ret;
3072 }
3073
3074 static struct xprt_class        xs_local_transport = {
3075         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3076         .name           = "named UNIX socket",
3077         .owner          = THIS_MODULE,
3078         .ident          = XPRT_TRANSPORT_LOCAL,
3079         .setup          = xs_setup_local,
3080 };
3081
3082 static struct xprt_class        xs_udp_transport = {
3083         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3084         .name           = "udp",
3085         .owner          = THIS_MODULE,
3086         .ident          = XPRT_TRANSPORT_UDP,
3087         .setup          = xs_setup_udp,
3088 };
3089
3090 static struct xprt_class        xs_tcp_transport = {
3091         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3092         .name           = "tcp",
3093         .owner          = THIS_MODULE,
3094         .ident          = XPRT_TRANSPORT_TCP,
3095         .setup          = xs_setup_tcp,
3096 };
3097
3098 static struct xprt_class        xs_bc_tcp_transport = {
3099         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3100         .name           = "tcp NFSv4.1 backchannel",
3101         .owner          = THIS_MODULE,
3102         .ident          = XPRT_TRANSPORT_BC_TCP,
3103         .setup          = xs_setup_bc_tcp,
3104 };
3105
3106 /**
3107  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3108  *
3109  */
3110 int init_socket_xprt(void)
3111 {
3112 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3113         if (!sunrpc_table_header)
3114                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3115 #endif
3116
3117         xprt_register_transport(&xs_local_transport);
3118         xprt_register_transport(&xs_udp_transport);
3119         xprt_register_transport(&xs_tcp_transport);
3120         xprt_register_transport(&xs_bc_tcp_transport);
3121
3122         return 0;
3123 }
3124
3125 /**
3126  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3127  *
3128  */
3129 void cleanup_socket_xprt(void)
3130 {
3131 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3132         if (sunrpc_table_header) {
3133                 unregister_sysctl_table(sunrpc_table_header);
3134                 sunrpc_table_header = NULL;
3135         }
3136 #endif
3137
3138         xprt_unregister_transport(&xs_local_transport);
3139         xprt_unregister_transport(&xs_udp_transport);
3140         xprt_unregister_transport(&xs_tcp_transport);
3141         xprt_unregister_transport(&xs_bc_tcp_transport);
3142 }
3143
3144 static int param_set_uint_minmax(const char *val,
3145                 const struct kernel_param *kp,
3146                 unsigned int min, unsigned int max)
3147 {
3148         unsigned int num;
3149         int ret;
3150
3151         if (!val)
3152                 return -EINVAL;
3153         ret = kstrtouint(val, 0, &num);
3154         if (ret)
3155                 return ret;
3156         if (num < min || num > max)
3157                 return -EINVAL;
3158         *((unsigned int *)kp->arg) = num;
3159         return 0;
3160 }
3161
3162 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3163 {
3164         return param_set_uint_minmax(val, kp,
3165                         RPC_MIN_RESVPORT,
3166                         RPC_MAX_RESVPORT);
3167 }
3168
3169 static const struct kernel_param_ops param_ops_portnr = {
3170         .set = param_set_portnr,
3171         .get = param_get_uint,
3172 };
3173
3174 #define param_check_portnr(name, p) \
3175         __param_check(name, p, unsigned int);
3176
3177 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3178 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3179
3180 static int param_set_slot_table_size(const char *val,
3181                                      const struct kernel_param *kp)
3182 {
3183         return param_set_uint_minmax(val, kp,
3184                         RPC_MIN_SLOT_TABLE,
3185                         RPC_MAX_SLOT_TABLE);
3186 }
3187
3188 static const struct kernel_param_ops param_ops_slot_table_size = {
3189         .set = param_set_slot_table_size,
3190         .get = param_get_uint,
3191 };
3192
3193 #define param_check_slot_table_size(name, p) \
3194         __param_check(name, p, unsigned int);
3195
3196 static int param_set_max_slot_table_size(const char *val,
3197                                      const struct kernel_param *kp)
3198 {
3199         return param_set_uint_minmax(val, kp,
3200                         RPC_MIN_SLOT_TABLE,
3201                         RPC_MAX_SLOT_TABLE_LIMIT);
3202 }
3203
3204 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3205         .set = param_set_max_slot_table_size,
3206         .get = param_get_uint,
3207 };
3208
3209 #define param_check_max_slot_table_size(name, p) \
3210         __param_check(name, p, unsigned int);
3211
3212 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3213                    slot_table_size, 0644);
3214 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3215                    max_slot_table_size, 0644);
3216 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3217                    slot_table_size, 0644);