net/sunrpc/xprtsock.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/net/sunrpc/xprtsock.c
   4  *
   5  * Client-side transport implementation for sockets.
   6  *
   7  * TCP callback races fixes (C) 1998 Red Hat
   8  * TCP send fixes (C) 1998 Red Hat
   9  * TCP NFS related read + write fixes
  10  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11  *
  12  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13  * Fix behaviour when socket buffer is full.
  14  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15  *
  16  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17  *
  18  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19  *   <gilles.quillard@bull.net>
  20  */
  21
  22 #include <linux/types.h>
  23 #include <linux/string.h>
  24 #include <linux/slab.h>
  25 #include <linux/module.h>
  26 #include <linux/capability.h>
  27 #include <linux/pagemap.h>
  28 #include <linux/errno.h>
  29 #include <linux/socket.h>
  30 #include <linux/in.h>
  31 #include <linux/net.h>
  32 #include <linux/mm.h>
  33 #include <linux/un.h>
  34 #include <linux/udp.h>
  35 #include <linux/tcp.h>
  36 #include <linux/sunrpc/clnt.h>
  37 #include <linux/sunrpc/addr.h>
  38 #include <linux/sunrpc/sched.h>
  39 #include <linux/sunrpc/svcsock.h>
  40 #include <linux/sunrpc/xprtsock.h>
  41 #include <linux/file.h>
  42 #ifdef CONFIG_SUNRPC_BACKCHANNEL
  43 #include <linux/sunrpc/bc_xprt.h>
  44 #endif
  45
  46 #include <net/sock.h>
  47 #include <net/checksum.h>
  48 #include <net/udp.h>
  49 #include <net/tcp.h>
  50 #include <linux/bvec.h>
  51 #include <linux/highmem.h>
  52 #include <linux/uio.h>
  53 #include <linux/sched/mm.h>
  54
  55 #include <trace/events/sunrpc.h>
  56
  57 #include "socklib.h"
  58 #include "sunrpc.h"
  59
  60 static void xs_close(struct rpc_xprt *xprt);
  61 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  62                 struct socket *sock);
  63
  64 /*
  65  * xprtsock tunables
  66  */
  67 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  68 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  69 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  70
  71 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  72 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  73
  74 #define XS_TCP_LINGER_TO        (15U * HZ)
  75 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  76
  77 /*
  78  * We can register our own files under /proc/sys/sunrpc by
  79  * calling register_sysctl_table() again.  The files in that
  80  * directory become the union of all files registered there.
  81  *
  82  * We simply need to make sure that we don't collide with
  83  * someone else's file names!
  84  */
  85
  86 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  87 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  88 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  89 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  90 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  91
  92 static struct ctl_table_header *sunrpc_table_header;
  93
  94 /*
  95  * FIXME: changing the UDP slot table size should also resize the UDP
  96  *        socket buffers for existing UDP transports
  97  */
  98 static struct ctl_table xs_tunables_table[] = {
  99         {
 100                 .procname       = "udp_slot_table_entries",
 101                 .data           = &xprt_udp_slot_table_entries,
 102                 .maxlen         = sizeof(unsigned int),
 103                 .mode           = 0644,
 104                 .proc_handler   = proc_dointvec_minmax,
 105                 .extra1         = &min_slot_table_size,
 106                 .extra2         = &max_slot_table_size
 107         },
 108         {
 109                 .procname       = "tcp_slot_table_entries",
 110                 .data           = &xprt_tcp_slot_table_entries,
 111                 .maxlen         = sizeof(unsigned int),
 112                 .mode           = 0644,
 113                 .proc_handler   = proc_dointvec_minmax,
 114                 .extra1         = &min_slot_table_size,
 115                 .extra2         = &max_slot_table_size
 116         },
 117         {
 118                 .procname       = "tcp_max_slot_table_entries",
 119                 .data           = &xprt_max_tcp_slot_table_entries,
 120                 .maxlen         = sizeof(unsigned int),
 121                 .mode           = 0644,
 122                 .proc_handler   = proc_dointvec_minmax,
 123                 .extra1         = &min_slot_table_size,
 124                 .extra2         = &max_tcp_slot_table_limit
 125         },
 126         {
 127                 .procname       = "min_resvport",
 128                 .data           = &xprt_min_resvport,
 129                 .maxlen         = sizeof(unsigned int),
 130                 .mode           = 0644,
 131                 .proc_handler   = proc_dointvec_minmax,
 132                 .extra1         = &xprt_min_resvport_limit,
 133                 .extra2         = &xprt_max_resvport_limit
 134         },
 135         {
 136                 .procname       = "max_resvport",
 137                 .data           = &xprt_max_resvport,
 138                 .maxlen         = sizeof(unsigned int),
 139                 .mode           = 0644,
 140                 .proc_handler   = proc_dointvec_minmax,
 141                 .extra1         = &xprt_min_resvport_limit,
 142                 .extra2         = &xprt_max_resvport_limit
 143         },
 144         {
 145                 .procname       = "tcp_fin_timeout",
 146                 .data           = &xs_tcp_fin_timeout,
 147                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 148                 .mode           = 0644,
 149                 .proc_handler   = proc_dointvec_jiffies,
 150         },
 151         { },
 152 };
 153
 154 static struct ctl_table sunrpc_table[] = {
 155         {
 156                 .procname       = "sunrpc",
 157                 .mode           = 0555,
 158                 .child          = xs_tunables_table
 159         },
 160         { },
 161 };
 162
 163 /*
 164  * Wait duration for a reply from the RPC portmapper.
 165  */
 166 #define XS_BIND_TO              (60U * HZ)
 167
 168 /*
 169  * Delay if a UDP socket connect error occurs.  This is most likely some
 170  * kind of resource problem on the local host.
 171  */
 172 #define XS_UDP_REEST_TO         (2U * HZ)
 173
 174 /*
 175  * The reestablish timeout allows clients to delay for a bit before attempting
 176  * to reconnect to a server that just dropped our connection.
 177  *
 178  * We implement an exponential backoff when trying to reestablish a TCP
 179  * transport connection with the server.  Some servers like to drop a TCP
 180  * connection when they are overworked, so we start with a short timeout and
 181  * increase over time if the server is down or not responding.
 182  */
 183 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 184
 185 /*
 186  * TCP idle timeout; client drops the transport socket if it is idle
 187  * for this long.  Note that we also timeout UDP sockets to prevent
 188  * holding port numbers when there is no RPC traffic.
 189  */
 190 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 191
 192 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 193 # undef  RPC_DEBUG_DATA
 194 # define RPCDBG_FACILITY        RPCDBG_TRANS
 195 #endif
 196
 197 #ifdef RPC_DEBUG_DATA
 198 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 199 {
 200         u8 *buf = (u8 *) packet;
 201         int j;
 202
 203         dprintk("RPC:       %s\n", msg);
 204         for (j = 0; j < count && j < 128; j += 4) {
 205                 if (!(j & 31)) {
 206                         if (j)
 207                                 dprintk("\n");
 208                         dprintk("0x%04x ", j);
 209                 }
 210                 dprintk("%02x%02x%02x%02x ",
 211                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 212         }
 213         dprintk("\n");
 214 }
 215 #else
 216 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 217 {
 218         /* NOP */
 219 }
 220 #endif
 221
 222 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 223 {
 224         return (struct rpc_xprt *) sk->sk_user_data;
 225 }
 226
 227 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 228 {
 229         return (struct sockaddr *) &xprt->addr;
 230 }
 231
 232 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 233 {
 234         return (struct sockaddr_un *) &xprt->addr;
 235 }
 236
 237 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 238 {
 239         return (struct sockaddr_in *) &xprt->addr;
 240 }
 241
 242 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 243 {
 244         return (struct sockaddr_in6 *) &xprt->addr;
 245 }
 246
 247 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 248 {
 249         struct sockaddr *sap = xs_addr(xprt);
 250         struct sockaddr_in6 *sin6;
 251         struct sockaddr_in *sin;
 252         struct sockaddr_un *sun;
 253         char buf[128];
 254
 255         switch (sap->sa_family) {
 256         case AF_LOCAL:
 257                 sun = xs_addr_un(xprt);
 258                 strlcpy(buf, sun->sun_path, sizeof(buf));
 259                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 260                                                 kstrdup(buf, GFP_KERNEL);
 261                 break;
 262         case AF_INET:
 263                 (void)rpc_ntop(sap, buf, sizeof(buf));
 264                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 265                                                 kstrdup(buf, GFP_KERNEL);
 266                 sin = xs_addr_in(xprt);
 267                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 268                 break;
 269         case AF_INET6:
 270                 (void)rpc_ntop(sap, buf, sizeof(buf));
 271                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 272                                                 kstrdup(buf, GFP_KERNEL);
 273                 sin6 = xs_addr_in6(xprt);
 274                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 275                 break;
 276         default:
 277                 BUG();
 278         }
 279
 280         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 281 }
 282
 283 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 284 {
 285         struct sockaddr *sap = xs_addr(xprt);
 286         char buf[128];
 287
 288         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 289         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 290
 291         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 292         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 293 }
 294
 295 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 296                                      const char *protocol,
 297                                      const char *netid)
 298 {
 299         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 300         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 301         xs_format_common_peer_addresses(xprt);
 302         xs_format_common_peer_ports(xprt);
 303 }
 304
 305 static void xs_update_peer_port(struct rpc_xprt *xprt)
 306 {
 307         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 308         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 309
 310         xs_format_common_peer_ports(xprt);
 311 }
 312
 313 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 314 {
 315         unsigned int i;
 316
 317         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 318                 switch (i) {
 319                 case RPC_DISPLAY_PROTO:
 320                 case RPC_DISPLAY_NETID:
 321                         continue;
 322                 default:
 323                         kfree(xprt->address_strings[i]);
 324                 }
 325 }
 326
 327 static size_t
 328 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 329 {
 330         size_t i,n;
 331
 332         if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 333                 return want;
 334         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 335         for (i = 0; i < n; i++) {
 336                 if (buf->pages[i])
 337                         continue;
 338                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 339                 if (!buf->pages[i]) {
 340                         i *= PAGE_SIZE;
 341                         return i > buf->page_base ? i - buf->page_base : 0;
 342                 }
 343         }
 344         return want;
 345 }
 346
 347 static ssize_t
 348 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 349 {
 350         ssize_t ret;
 351         if (seek != 0)
 352                 iov_iter_advance(&msg->msg_iter, seek);
 353         ret = sock_recvmsg(sock, msg, flags);
 354         return ret > 0 ? ret + seek : ret;
 355 }
 356
 357 static ssize_t
 358 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 359                 struct kvec *kvec, size_t count, size_t seek)
 360 {
 361         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 362         return xs_sock_recvmsg(sock, msg, flags, seek);
 363 }
 364
 365 static ssize_t
 366 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 367                 struct bio_vec *bvec, unsigned long nr, size_t count,
 368                 size_t seek)
 369 {
 370         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 371         return xs_sock_recvmsg(sock, msg, flags, seek);
 372 }
 373
 374 static ssize_t
 375 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 376                 size_t count)
 377 {
 378         iov_iter_discard(&msg->msg_iter, READ, count);
 379         return sock_recvmsg(sock, msg, flags);
 380 }
 381
 382 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 383 static void
 384 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 385 {
 386         struct bvec_iter bi = {
 387                 .bi_size = count,
 388         };
 389         struct bio_vec bv;
 390
 391         bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 392         for_each_bvec(bv, bvec, bi, bi)
 393                 flush_dcache_page(bv.bv_page);
 394 }
 395 #else
 396 static inline void
 397 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 398 {
 399 }
 400 #endif
 401
 402 static ssize_t
 403 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 404                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 405 {
 406         size_t want, seek_init = seek, offset = 0;
 407         ssize_t ret;
 408
 409         want = min_t(size_t, count, buf->head[0].iov_len);
 410         if (seek < want) {
 411                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 412                 if (ret <= 0)
 413                         goto sock_err;
 414                 offset += ret;
 415                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 416                         goto out;
 417                 if (ret != want)
 418                         goto out;
 419                 seek = 0;
 420         } else {
 421                 seek -= want;
 422                 offset += want;
 423         }
 424
 425         want = xs_alloc_sparse_pages(buf,
 426                         min_t(size_t, count - offset, buf->page_len),
 427                         GFP_KERNEL);
 428         if (seek < want) {
 429                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 430                                 xdr_buf_pagecount(buf),
 431                                 want + buf->page_base,
 432                                 seek + buf->page_base);
 433                 if (ret <= 0)
 434                         goto sock_err;
 435                 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 436                 offset += ret - buf->page_base;
 437                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 438                         goto out;
 439                 if (ret != want)
 440                         goto out;
 441                 seek = 0;
 442         } else {
 443                 seek -= want;
 444                 offset += want;
 445         }
 446
 447         want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 448         if (seek < want) {
 449                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 450                 if (ret <= 0)
 451                         goto sock_err;
 452                 offset += ret;
 453                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 454                         goto out;
 455                 if (ret != want)
 456                         goto out;
 457         } else if (offset < seek_init)
 458                 offset = seek_init;
 459         ret = -EMSGSIZE;
 460 out:
 461         *read = offset - seek_init;
 462         return ret;
 463 sock_err:
 464         offset += seek;
 465         goto out;
 466 }
 467
 468 static void
 469 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 470 {
 471         if (!transport->recv.copied) {
 472                 if (buf->head[0].iov_len >= transport->recv.offset)
 473                         memcpy(buf->head[0].iov_base,
 474                                         &transport->recv.xid,
 475                                         transport->recv.offset);
 476                 transport->recv.copied = transport->recv.offset;
 477         }
 478 }
 479
 480 static bool
 481 xs_read_stream_request_done(struct sock_xprt *transport)
 482 {
 483         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 484 }
 485
 486 static void
 487 xs_read_stream_check_eor(struct sock_xprt *transport,
 488                 struct msghdr *msg)
 489 {
 490         if (xs_read_stream_request_done(transport))
 491                 msg->msg_flags |= MSG_EOR;
 492 }
 493
 494 static ssize_t
 495 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 496                 int flags, struct rpc_rqst *req)
 497 {
 498         struct xdr_buf *buf = &req->rq_private_buf;
 499         size_t want, uninitialized_var(read);
 500         ssize_t uninitialized_var(ret);
 501
 502         xs_read_header(transport, buf);
 503
 504         want = transport->recv.len - transport->recv.offset;
 505         if (want != 0) {
 506                 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 507                                 transport->recv.copied + want,
 508                                 transport->recv.copied,
 509                                 &read);
 510                 transport->recv.offset += read;
 511                 transport->recv.copied += read;
 512         }
 513
 514         if (transport->recv.offset == transport->recv.len)
 515                 xs_read_stream_check_eor(transport, msg);
 516
 517         if (want == 0)
 518                 return 0;
 519
 520         switch (ret) {
 521         default:
 522                 break;
 523         case -EFAULT:
 524         case -EMSGSIZE:
 525                 msg->msg_flags |= MSG_TRUNC;
 526                 return read;
 527         case 0:
 528                 return -ESHUTDOWN;
 529         }
 530         return ret < 0 ? ret : read;
 531 }
 532
 533 static size_t
 534 xs_read_stream_headersize(bool isfrag)
 535 {
 536         if (isfrag)
 537                 return sizeof(__be32);
 538         return 3 * sizeof(__be32);
 539 }
 540
 541 static ssize_t
 542 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 543                 int flags, size_t want, size_t seek)
 544 {
 545         struct kvec kvec = {
 546                 .iov_base = &transport->recv.fraghdr,
 547                 .iov_len = want,
 548         };
 549         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 550 }
 551
 552 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 553 static ssize_t
 554 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 555 {
 556         struct rpc_xprt *xprt = &transport->xprt;
 557         struct rpc_rqst *req;
 558         ssize_t ret;
 559
 560         /* Look up and lock the request corresponding to the given XID */
 561         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 562         if (!req) {
 563                 printk(KERN_WARNING "Callback slot table overflowed\n");
 564                 return -ESHUTDOWN;
 565         }
 566         if (transport->recv.copied && !req->rq_private_buf.len)
 567                 return -ESHUTDOWN;
 568
 569         ret = xs_read_stream_request(transport, msg, flags, req);
 570         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 571                 xprt_complete_bc_request(req, transport->recv.copied);
 572         else
 573                 req->rq_private_buf.len = transport->recv.copied;
 574
 575         return ret;
 576 }
 577 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 578 static ssize_t
 579 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 580 {
 581         return -ESHUTDOWN;
 582 }
 583 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 584
 585 static ssize_t
 586 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 587 {
 588         struct rpc_xprt *xprt = &transport->xprt;
 589         struct rpc_rqst *req;
 590         ssize_t ret = 0;
 591
 592         /* Look up and lock the request corresponding to the given XID */
 593         spin_lock(&xprt->queue_lock);
 594         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 595         if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 596                 msg->msg_flags |= MSG_TRUNC;
 597                 goto out;
 598         }
 599         xprt_pin_rqst(req);
 600         spin_unlock(&xprt->queue_lock);
 601
 602         ret = xs_read_stream_request(transport, msg, flags, req);
 603
 604         spin_lock(&xprt->queue_lock);
 605         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 606                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 607         else
 608                 req->rq_private_buf.len = transport->recv.copied;
 609         xprt_unpin_rqst(req);
 610 out:
 611         spin_unlock(&xprt->queue_lock);
 612         return ret;
 613 }
 614
 615 static ssize_t
 616 xs_read_stream(struct sock_xprt *transport, int flags)
 617 {
 618         struct msghdr msg = { 0 };
 619         size_t want, read = 0;
 620         ssize_t ret = 0;
 621
 622         if (transport->recv.len == 0) {
 623                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 624                 ret = xs_read_stream_header(transport, &msg, flags, want,
 625                                 transport->recv.offset);
 626                 if (ret <= 0)
 627                         goto out_err;
 628                 transport->recv.offset = ret;
 629                 if (transport->recv.offset != want)
 630                         return transport->recv.offset;
 631                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 632                         RPC_FRAGMENT_SIZE_MASK;
 633                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 634                 read = ret;
 635         }
 636
 637         switch (be32_to_cpu(transport->recv.calldir)) {
 638         default:
 639                 msg.msg_flags |= MSG_TRUNC;
 640                 break;
 641         case RPC_CALL:
 642                 ret = xs_read_stream_call(transport, &msg, flags);
 643                 break;
 644         case RPC_REPLY:
 645                 ret = xs_read_stream_reply(transport, &msg, flags);
 646         }
 647         if (msg.msg_flags & MSG_TRUNC) {
 648                 transport->recv.calldir = cpu_to_be32(-1);
 649                 transport->recv.copied = -1;
 650         }
 651         if (ret < 0)
 652                 goto out_err;
 653         read += ret;
 654         if (transport->recv.offset < transport->recv.len) {
 655                 if (!(msg.msg_flags & MSG_TRUNC))
 656                         return read;
 657                 msg.msg_flags = 0;
 658                 ret = xs_read_discard(transport->sock, &msg, flags,
 659                                 transport->recv.len - transport->recv.offset);
 660                 if (ret <= 0)
 661                         goto out_err;
 662                 transport->recv.offset += ret;
 663                 read += ret;
 664                 if (transport->recv.offset != transport->recv.len)
 665                         return read;
 666         }
 667         if (xs_read_stream_request_done(transport)) {
 668                 trace_xs_stream_read_request(transport);
 669                 transport->recv.copied = 0;
 670         }
 671         transport->recv.offset = 0;
 672         transport->recv.len = 0;
 673         return read;
 674 out_err:
 675         return ret != 0 ? ret : -ESHUTDOWN;
 676 }
 677
 678 static __poll_t xs_poll_socket(struct sock_xprt *transport)
 679 {
 680         return transport->sock->ops->poll(transport->file, transport->sock,
 681                         NULL);
 682 }
 683
 684 static bool xs_poll_socket_readable(struct sock_xprt *transport)
 685 {
 686         __poll_t events = xs_poll_socket(transport);
 687
 688         return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 689 }
 690
 691 static void xs_poll_check_readable(struct sock_xprt *transport)
 692 {
 693
 694         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 695         if (!xs_poll_socket_readable(transport))
 696                 return;
 697         if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 698                 queue_work(xprtiod_workqueue, &transport->recv_worker);
 699 }
 700
 701 static void xs_stream_data_receive(struct sock_xprt *transport)
 702 {
 703         size_t read = 0;
 704         ssize_t ret = 0;
 705
 706         mutex_lock(&transport->recv_mutex);
 707         if (transport->sock == NULL)
 708                 goto out;
 709         for (;;) {
 710                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 711                 if (ret < 0)
 712                         break;
 713                 read += ret;
 714                 cond_resched();
 715         }
 716         if (ret == -ESHUTDOWN)
 717                 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 718         else
 719                 xs_poll_check_readable(transport);
 720 out:
 721         mutex_unlock(&transport->recv_mutex);
 722         trace_xs_stream_read_data(&transport->xprt, ret, read);
 723 }
 724
 725 static void xs_stream_data_receive_workfn(struct work_struct *work)
 726 {
 727         struct sock_xprt *transport =
 728                 container_of(work, struct sock_xprt, recv_worker);
 729         unsigned int pflags = memalloc_nofs_save();
 730
 731         xs_stream_data_receive(transport);
 732         memalloc_nofs_restore(pflags);
 733 }
 734
 735 static void
 736 xs_stream_reset_connect(struct sock_xprt *transport)
 737 {
 738         transport->recv.offset = 0;
 739         transport->recv.len = 0;
 740         transport->recv.copied = 0;
 741         transport->xmit.offset = 0;
 742 }
 743
 744 static void
 745 xs_stream_start_connect(struct sock_xprt *transport)
 746 {
 747         transport->xprt.stat.connect_count++;
 748         transport->xprt.stat.connect_start = jiffies;
 749 }
 750
 751 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 752
 753 /**
 754  * xs_nospace - handle transmit was incomplete
 755  * @req: pointer to RPC request
 756  *
 757  */
 758 static int xs_nospace(struct rpc_rqst *req)
 759 {
 760         struct rpc_xprt *xprt = req->rq_xprt;
 761         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 762         struct sock *sk = transport->inet;
 763         int ret = -EAGAIN;
 764
 765         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 766                         req->rq_task->tk_pid,
 767                         req->rq_slen - transport->xmit.offset,
 768                         req->rq_slen);
 769
 770         /* Protect against races with write_space */
 771         spin_lock(&xprt->transport_lock);
 772
 773         /* Don't race with disconnect */
 774         if (xprt_connected(xprt)) {
 775                 /* wait for more buffer space */
 776                 sk->sk_write_pending++;
 777                 xprt_wait_for_buffer_space(xprt);
 778         } else
 779                 ret = -ENOTCONN;
 780
 781         spin_unlock(&xprt->transport_lock);
 782
 783         /* Race breaker in case memory is freed before above code is called */
 784         if (ret == -EAGAIN) {
 785                 struct socket_wq *wq;
 786
 787                 rcu_read_lock();
 788                 wq = rcu_dereference(sk->sk_wq);
 789                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 790                 rcu_read_unlock();
 791
 792                 sk->sk_write_space(sk);
 793         }
 794         return ret;
 795 }
 796
 797 static void
 798 xs_stream_prepare_request(struct rpc_rqst *req)
 799 {
 800         xdr_free_bvec(&req->rq_rcv_buf);
 801         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 802 }
 803
 804 /*
 805  * Determine if the previous message in the stream was aborted before it
 806  * could complete transmission.
 807  */
 808 static bool
 809 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 810 {
 811         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 812 }
 813
 814 /*
 815  * Return the stream record marker field for a record of length < 2^31-1
 816  */
 817 static rpc_fraghdr
 818 xs_stream_record_marker(struct xdr_buf *xdr)
 819 {
 820         if (!xdr->len)
 821                 return 0;
 822         return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 823 }
 824
 825 /**
 826  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 827  * @req: pointer to RPC request
 828  *
 829  * Return values:
 830  *        0:    The request has been sent
 831  *   EAGAIN:    The socket was blocked, please call again later to
 832  *              complete the request
 833  * ENOTCONN:    Caller needs to invoke connect logic then call again
 834  *    other:    Some other error occured, the request was not sent
 835  */
 836 static int xs_local_send_request(struct rpc_rqst *req)
 837 {
 838         struct rpc_xprt *xprt = req->rq_xprt;
 839         struct sock_xprt *transport =
 840                                 container_of(xprt, struct sock_xprt, xprt);
 841         struct xdr_buf *xdr = &req->rq_snd_buf;
 842         rpc_fraghdr rm = xs_stream_record_marker(xdr);
 843         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 844         struct msghdr msg = {
 845                 .msg_flags      = XS_SENDMSG_FLAGS,
 846         };
 847         unsigned int uninitialized_var(sent);
 848         int status;
 849
 850         /* Close the stream if the previous transmission was incomplete */
 851         if (xs_send_request_was_aborted(transport, req)) {
 852                 xs_close(xprt);
 853                 return -ENOTCONN;
 854         }
 855
 856         xs_pktdump("packet data:",
 857                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 858
 859         req->rq_xtime = ktime_get();
 860         status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 861                                    transport->xmit.offset, rm, &sent);
 862         dprintk("RPC:       %s(%u) = %d\n",
 863                         __func__, xdr->len - transport->xmit.offset, status);
 864
 865         if (status == -EAGAIN && sock_writeable(transport->inet))
 866                 status = -ENOBUFS;
 867
 868         if (likely(sent > 0) || status == 0) {
 869                 transport->xmit.offset += sent;
 870                 req->rq_bytes_sent = transport->xmit.offset;
 871                 if (likely(req->rq_bytes_sent >= msglen)) {
 872                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 873                         transport->xmit.offset = 0;
 874                         return 0;
 875                 }
 876                 status = -EAGAIN;
 877         }
 878
 879         switch (status) {
 880         case -ENOBUFS:
 881                 break;
 882         case -EAGAIN:
 883                 status = xs_nospace(req);
 884                 break;
 885         default:
 886                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 887                         -status);
 888                 /* fall through */
 889         case -EPIPE:
 890                 xs_close(xprt);
 891                 status = -ENOTCONN;
 892         }
 893
 894         return status;
 895 }
 896
 897 /**
 898  * xs_udp_send_request - write an RPC request to a UDP socket
 899  * @req: pointer to RPC request
 900  *
 901  * Return values:
 902  *        0:    The request has been sent
 903  *   EAGAIN:    The socket was blocked, please call again later to
 904  *              complete the request
 905  * ENOTCONN:    Caller needs to invoke connect logic then call again
 906  *    other:    Some other error occurred, the request was not sent
 907  */
 908 static int xs_udp_send_request(struct rpc_rqst *req)
 909 {
 910         struct rpc_xprt *xprt = req->rq_xprt;
 911         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 912         struct xdr_buf *xdr = &req->rq_snd_buf;
 913         struct msghdr msg = {
 914                 .msg_name       = xs_addr(xprt),
 915                 .msg_namelen    = xprt->addrlen,
 916                 .msg_flags      = XS_SENDMSG_FLAGS,
 917         };
 918         unsigned int uninitialized_var(sent);
 919         int status;
 920
 921         xs_pktdump("packet data:",
 922                                 req->rq_svec->iov_base,
 923                                 req->rq_svec->iov_len);
 924
 925         if (!xprt_bound(xprt))
 926                 return -ENOTCONN;
 927
 928         if (!xprt_request_get_cong(xprt, req))
 929                 return -EBADSLT;
 930
 931         req->rq_xtime = ktime_get();
 932         status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
 933
 934         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 935                         xdr->len, status);
 936
 937         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 938         if (status == -EPERM)
 939                 goto process_status;
 940
 941         if (status == -EAGAIN && sock_writeable(transport->inet))
 942                 status = -ENOBUFS;
 943
 944         if (sent > 0 || status == 0) {
 945                 req->rq_xmit_bytes_sent += sent;
 946                 if (sent >= req->rq_slen)
 947                         return 0;
 948                 /* Still some bytes left; set up for a retry later. */
 949                 status = -EAGAIN;
 950         }
 951
 952 process_status:
 953         switch (status) {
 954         case -ENOTSOCK:
 955                 status = -ENOTCONN;
 956                 /* Should we call xs_close() here? */
 957                 break;
 958         case -EAGAIN:
 959                 status = xs_nospace(req);
 960                 break;
 961         case -ENETUNREACH:
 962         case -ENOBUFS:
 963         case -EPIPE:
 964         case -ECONNREFUSED:
 965         case -EPERM:
 966                 /* When the server has died, an ICMP port unreachable message
 967                  * prompts ECONNREFUSED. */
 968                 break;
 969         default:
 970                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 971                         -status);
 972         }
 973
 974         return status;
 975 }
 976
 977 /**
 978  * xs_tcp_send_request - write an RPC request to a TCP socket
 979  * @req: pointer to RPC request
 980  *
 981  * Return values:
 982  *        0:    The request has been sent
 983  *   EAGAIN:    The socket was blocked, please call again later to
 984  *              complete the request
 985  * ENOTCONN:    Caller needs to invoke connect logic then call again
 986  *    other:    Some other error occurred, the request was not sent
 987  *
 988  * XXX: In the case of soft timeouts, should we eventually give up
 989  *      if sendmsg is not able to make progress?
 990  */
 991 static int xs_tcp_send_request(struct rpc_rqst *req)
 992 {
 993         struct rpc_xprt *xprt = req->rq_xprt;
 994         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 995         struct xdr_buf *xdr = &req->rq_snd_buf;
 996         rpc_fraghdr rm = xs_stream_record_marker(xdr);
 997         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 998         struct msghdr msg = {
 999                 .msg_flags      = XS_SENDMSG_FLAGS,
1000         };
1001         bool vm_wait = false;
1002         unsigned int uninitialized_var(sent);
1003         int status;
1004
1005         /* Close the stream if the previous transmission was incomplete */
1006         if (xs_send_request_was_aborted(transport, req)) {
1007                 if (transport->sock != NULL)
1008                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1009                 return -ENOTCONN;
1010         }
1011
1012         xs_pktdump("packet data:",
1013                                 req->rq_svec->iov_base,
1014                                 req->rq_svec->iov_len);
1015
1016         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1017                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1018
1019         /* Continue transmitting the packet/record. We must be careful
1020          * to cope with writespace callbacks arriving _after_ we have
1021          * called sendmsg(). */
1022         req->rq_xtime = ktime_get();
1023         while (1) {
1024                 status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1025                                            transport->xmit.offset, rm, &sent);
1026
1027                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1028                                 xdr->len - transport->xmit.offset, status);
1029
1030                 /* If we've sent the entire packet, immediately
1031                  * reset the count of bytes sent. */
1032                 transport->xmit.offset += sent;
1033                 req->rq_bytes_sent = transport->xmit.offset;
1034                 if (likely(req->rq_bytes_sent >= msglen)) {
1035                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1036                         transport->xmit.offset = 0;
1037                         return 0;
1038                 }
1039
1040                 WARN_ON_ONCE(sent == 0 && status == 0);
1041
1042                 if (status == -EAGAIN ) {
1043                         /*
1044                          * Return EAGAIN if we're sure we're hitting the
1045                          * socket send buffer limits.
1046                          */
1047                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1048                                 break;
1049                         /*
1050                          * Did we hit a memory allocation failure?
1051                          */
1052                         if (sent == 0) {
1053                                 status = -ENOBUFS;
1054                                 if (vm_wait)
1055                                         break;
1056                                 /* Retry, knowing now that we're below the
1057                                  * socket send buffer limit
1058                                  */
1059                                 vm_wait = true;
1060                         }
1061                         continue;
1062                 }
1063                 if (status < 0)
1064                         break;
1065                 vm_wait = false;
1066         }
1067
1068         switch (status) {
1069         case -ENOTSOCK:
1070                 status = -ENOTCONN;
1071                 /* Should we call xs_close() here? */
1072                 break;
1073         case -EAGAIN:
1074                 status = xs_nospace(req);
1075                 break;
1076         case -ECONNRESET:
1077         case -ECONNREFUSED:
1078         case -ENOTCONN:
1079         case -EADDRINUSE:
1080         case -ENOBUFS:
1081         case -EPIPE:
1082                 break;
1083         default:
1084                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1085                         -status);
1086         }
1087
1088         return status;
1089 }
1090
1091 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1092 {
1093         transport->old_data_ready = sk->sk_data_ready;
1094         transport->old_state_change = sk->sk_state_change;
1095         transport->old_write_space = sk->sk_write_space;
1096         transport->old_error_report = sk->sk_error_report;
1097 }
1098
1099 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1100 {
1101         sk->sk_data_ready = transport->old_data_ready;
1102         sk->sk_state_change = transport->old_state_change;
1103         sk->sk_write_space = transport->old_write_space;
1104         sk->sk_error_report = transport->old_error_report;
1105 }
1106
1107 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1108 {
1109         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1110
1111         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1112         clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1113         clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1114         clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1115 }
1116
1117 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1118 {
1119         set_bit(nr, &transport->sock_state);
1120         queue_work(xprtiod_workqueue, &transport->error_worker);
1121 }
1122
1123 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1124 {
1125         smp_mb__before_atomic();
1126         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1127         clear_bit(XPRT_CLOSING, &xprt->state);
1128         xs_sock_reset_state_flags(xprt);
1129         smp_mb__after_atomic();
1130 }
1131
1132 /**
1133  * xs_error_report - callback to handle TCP socket state errors
1134  * @sk: socket
1135  *
1136  * Note: we don't call sock_error() since there may be a rpc_task
1137  * using the socket, and so we don't want to clear sk->sk_err.
1138  */
1139 static void xs_error_report(struct sock *sk)
1140 {
1141         struct sock_xprt *transport;
1142         struct rpc_xprt *xprt;
1143
1144         read_lock_bh(&sk->sk_callback_lock);
1145         if (!(xprt = xprt_from_sock(sk)))
1146                 goto out;
1147
1148         transport = container_of(xprt, struct sock_xprt, xprt);
1149         transport->xprt_err = -sk->sk_err;
1150         if (transport->xprt_err == 0)
1151                 goto out;
1152         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1153                         xprt, -transport->xprt_err);
1154         trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1155
1156         /* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1157         smp_mb__before_atomic();
1158         xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1159  out:
1160         read_unlock_bh(&sk->sk_callback_lock);
1161 }
1162
1163 static void xs_reset_transport(struct sock_xprt *transport)
1164 {
1165         struct socket *sock = transport->sock;
1166         struct sock *sk = transport->inet;
1167         struct rpc_xprt *xprt = &transport->xprt;
1168         struct file *filp = transport->file;
1169
1170         if (sk == NULL)
1171                 return;
1172
1173         if (atomic_read(&transport->xprt.swapper))
1174                 sk_clear_memalloc(sk);
1175
1176         kernel_sock_shutdown(sock, SHUT_RDWR);
1177
1178         mutex_lock(&transport->recv_mutex);
1179         write_lock_bh(&sk->sk_callback_lock);
1180         transport->inet = NULL;
1181         transport->sock = NULL;
1182         transport->file = NULL;
1183
1184         sk->sk_user_data = NULL;
1185
1186         xs_restore_old_callbacks(transport, sk);
1187         xprt_clear_connected(xprt);
1188         write_unlock_bh(&sk->sk_callback_lock);
1189         xs_sock_reset_connection_flags(xprt);
1190         /* Reset stream record info */
1191         xs_stream_reset_connect(transport);
1192         mutex_unlock(&transport->recv_mutex);
1193
1194         trace_rpc_socket_close(xprt, sock);
1195         fput(filp);
1196
1197         xprt_disconnect_done(xprt);
1198 }
1199
1200 /**
1201  * xs_close - close a socket
1202  * @xprt: transport
1203  *
1204  * This is used when all requests are complete; ie, no DRC state remains
1205  * on the server we want to save.
1206  *
1207  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1208  * xs_reset_transport() zeroing the socket from underneath a writer.
1209  */
1210 static void xs_close(struct rpc_xprt *xprt)
1211 {
1212         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1213
1214         dprintk("RPC:       xs_close xprt %p\n", xprt);
1215
1216         xs_reset_transport(transport);
1217         xprt->reestablish_timeout = 0;
1218 }
1219
1220 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1221 {
1222         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1223                 xprt);
1224         xprt_disconnect_done(xprt);
1225 }
1226
1227 static void xs_xprt_free(struct rpc_xprt *xprt)
1228 {
1229         xs_free_peer_addresses(xprt);
1230         xprt_free(xprt);
1231 }
1232
1233 /**
1234  * xs_destroy - prepare to shutdown a transport
1235  * @xprt: doomed transport
1236  *
1237  */
1238 static void xs_destroy(struct rpc_xprt *xprt)
1239 {
1240         struct sock_xprt *transport = container_of(xprt,
1241                         struct sock_xprt, xprt);
1242         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1243
1244         cancel_delayed_work_sync(&transport->connect_worker);
1245         xs_close(xprt);
1246         cancel_work_sync(&transport->recv_worker);
1247         cancel_work_sync(&transport->error_worker);
1248         xs_xprt_free(xprt);
1249         module_put(THIS_MODULE);
1250 }
1251
1252 /**
1253  * xs_udp_data_read_skb - receive callback for UDP sockets
1254  * @xprt: transport
1255  * @sk: socket
1256  * @skb: skbuff
1257  *
1258  */
1259 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1260                 struct sock *sk,
1261                 struct sk_buff *skb)
1262 {
1263         struct rpc_task *task;
1264         struct rpc_rqst *rovr;
1265         int repsize, copied;
1266         u32 _xid;
1267         __be32 *xp;
1268
1269         repsize = skb->len;
1270         if (repsize < 4) {
1271                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1272                 return;
1273         }
1274
1275         /* Copy the XID from the skb... */
1276         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1277         if (xp == NULL)
1278                 return;
1279
1280         /* Look up and lock the request corresponding to the given XID */
1281         spin_lock(&xprt->queue_lock);
1282         rovr = xprt_lookup_rqst(xprt, *xp);
1283         if (!rovr)
1284                 goto out_unlock;
1285         xprt_pin_rqst(rovr);
1286         xprt_update_rtt(rovr->rq_task);
1287         spin_unlock(&xprt->queue_lock);
1288         task = rovr->rq_task;
1289
1290         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1291                 copied = repsize;
1292
1293         /* Suck it into the iovec, verify checksum if not done by hw. */
1294         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1295                 spin_lock(&xprt->queue_lock);
1296                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1297                 goto out_unpin;
1298         }
1299
1300
1301         spin_lock(&xprt->transport_lock);
1302         xprt_adjust_cwnd(xprt, task, copied);
1303         spin_unlock(&xprt->transport_lock);
1304         spin_lock(&xprt->queue_lock);
1305         xprt_complete_rqst(task, copied);
1306         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1307 out_unpin:
1308         xprt_unpin_rqst(rovr);
1309  out_unlock:
1310         spin_unlock(&xprt->queue_lock);
1311 }
1312
1313 static void xs_udp_data_receive(struct sock_xprt *transport)
1314 {
1315         struct sk_buff *skb;
1316         struct sock *sk;
1317         int err;
1318
1319         mutex_lock(&transport->recv_mutex);
1320         sk = transport->inet;
1321         if (sk == NULL)
1322                 goto out;
1323         for (;;) {
1324                 skb = skb_recv_udp(sk, 0, 1, &err);
1325                 if (skb == NULL)
1326                         break;
1327                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1328                 consume_skb(skb);
1329                 cond_resched();
1330         }
1331         xs_poll_check_readable(transport);
1332 out:
1333         mutex_unlock(&transport->recv_mutex);
1334 }
1335
1336 static void xs_udp_data_receive_workfn(struct work_struct *work)
1337 {
1338         struct sock_xprt *transport =
1339                 container_of(work, struct sock_xprt, recv_worker);
1340         unsigned int pflags = memalloc_nofs_save();
1341
1342         xs_udp_data_receive(transport);
1343         memalloc_nofs_restore(pflags);
1344 }
1345
1346 /**
1347  * xs_data_ready - "data ready" callback for UDP sockets
1348  * @sk: socket with data to read
1349  *
1350  */
1351 static void xs_data_ready(struct sock *sk)
1352 {
1353         struct rpc_xprt *xprt;
1354
1355         read_lock_bh(&sk->sk_callback_lock);
1356         dprintk("RPC:       xs_data_ready...\n");
1357         xprt = xprt_from_sock(sk);
1358         if (xprt != NULL) {
1359                 struct sock_xprt *transport = container_of(xprt,
1360                                 struct sock_xprt, xprt);
1361                 transport->old_data_ready(sk);
1362                 /* Any data means we had a useful conversation, so
1363                  * then we don't need to delay the next reconnect
1364                  */
1365                 if (xprt->reestablish_timeout)
1366                         xprt->reestablish_timeout = 0;
1367                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1368                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1369         }
1370         read_unlock_bh(&sk->sk_callback_lock);
1371 }
1372
1373 /*
1374  * Helper function to force a TCP close if the server is sending
1375  * junk and/or it has put us in CLOSE_WAIT
1376  */
1377 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1378 {
1379         xprt_force_disconnect(xprt);
1380 }
1381
1382 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1383 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1384 {
1385         return PAGE_SIZE;
1386 }
1387 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1388
1389 /**
1390  * xs_tcp_state_change - callback to handle TCP socket state changes
1391  * @sk: socket whose state has changed
1392  *
1393  */
1394 static void xs_tcp_state_change(struct sock *sk)
1395 {
1396         struct rpc_xprt *xprt;
1397         struct sock_xprt *transport;
1398
1399         read_lock_bh(&sk->sk_callback_lock);
1400         if (!(xprt = xprt_from_sock(sk)))
1401                 goto out;
1402         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1403         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1404                         sk->sk_state, xprt_connected(xprt),
1405                         sock_flag(sk, SOCK_DEAD),
1406                         sock_flag(sk, SOCK_ZAPPED),
1407                         sk->sk_shutdown);
1408
1409         transport = container_of(xprt, struct sock_xprt, xprt);
1410         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1411         switch (sk->sk_state) {
1412         case TCP_ESTABLISHED:
1413                 if (!xprt_test_and_set_connected(xprt)) {
1414                         xprt->connect_cookie++;
1415                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1416                         xprt_clear_connecting(xprt);
1417
1418                         xprt->stat.connect_count++;
1419                         xprt->stat.connect_time += (long)jiffies -
1420                                                    xprt->stat.connect_start;
1421                         xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1422                 }
1423                 break;
1424         case TCP_FIN_WAIT1:
1425                 /* The client initiated a shutdown of the socket */
1426                 xprt->connect_cookie++;
1427                 xprt->reestablish_timeout = 0;
1428                 set_bit(XPRT_CLOSING, &xprt->state);
1429                 smp_mb__before_atomic();
1430                 clear_bit(XPRT_CONNECTED, &xprt->state);
1431                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1432                 smp_mb__after_atomic();
1433                 break;
1434         case TCP_CLOSE_WAIT:
1435                 /* The server initiated a shutdown of the socket */
1436                 xprt->connect_cookie++;
1437                 clear_bit(XPRT_CONNECTED, &xprt->state);
1438                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1439                 /* fall through */
1440         case TCP_CLOSING:
1441                 /*
1442                  * If the server closed down the connection, make sure that
1443                  * we back off before reconnecting
1444                  */
1445                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1446                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1447                 break;
1448         case TCP_LAST_ACK:
1449                 set_bit(XPRT_CLOSING, &xprt->state);
1450                 smp_mb__before_atomic();
1451                 clear_bit(XPRT_CONNECTED, &xprt->state);
1452                 smp_mb__after_atomic();
1453                 break;
1454         case TCP_CLOSE:
1455                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1456                                         &transport->sock_state))
1457                         xprt_clear_connecting(xprt);
1458                 clear_bit(XPRT_CLOSING, &xprt->state);
1459                 /* Trigger the socket release */
1460                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1461         }
1462  out:
1463         read_unlock_bh(&sk->sk_callback_lock);
1464 }
1465
1466 static void xs_write_space(struct sock *sk)
1467 {
1468         struct socket_wq *wq;
1469         struct sock_xprt *transport;
1470         struct rpc_xprt *xprt;
1471
1472         if (!sk->sk_socket)
1473                 return;
1474         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1475
1476         if (unlikely(!(xprt = xprt_from_sock(sk))))
1477                 return;
1478         transport = container_of(xprt, struct sock_xprt, xprt);
1479         rcu_read_lock();
1480         wq = rcu_dereference(sk->sk_wq);
1481         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1482                 goto out;
1483
1484         xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1485         sk->sk_write_pending--;
1486 out:
1487         rcu_read_unlock();
1488 }
1489
1490 /**
1491  * xs_udp_write_space - callback invoked when socket buffer space
1492  *                             becomes available
1493  * @sk: socket whose state has changed
1494  *
1495  * Called when more output buffer space is available for this socket.
1496  * We try not to wake our writers until they can make "significant"
1497  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1498  * with a bunch of small requests.
1499  */
1500 static void xs_udp_write_space(struct sock *sk)
1501 {
1502         read_lock_bh(&sk->sk_callback_lock);
1503
1504         /* from net/core/sock.c:sock_def_write_space */
1505         if (sock_writeable(sk))
1506                 xs_write_space(sk);
1507
1508         read_unlock_bh(&sk->sk_callback_lock);
1509 }
1510
1511 /**
1512  * xs_tcp_write_space - callback invoked when socket buffer space
1513  *                             becomes available
1514  * @sk: socket whose state has changed
1515  *
1516  * Called when more output buffer space is available for this socket.
1517  * We try not to wake our writers until they can make "significant"
1518  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1519  * with a bunch of small requests.
1520  */
1521 static void xs_tcp_write_space(struct sock *sk)
1522 {
1523         read_lock_bh(&sk->sk_callback_lock);
1524
1525         /* from net/core/stream.c:sk_stream_write_space */
1526         if (sk_stream_is_writeable(sk))
1527                 xs_write_space(sk);
1528
1529         read_unlock_bh(&sk->sk_callback_lock);
1530 }
1531
1532 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1533 {
1534         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1535         struct sock *sk = transport->inet;
1536
1537         if (transport->rcvsize) {
1538                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1539                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1540         }
1541         if (transport->sndsize) {
1542                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1543                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1544                 sk->sk_write_space(sk);
1545         }
1546 }
1547
1548 /**
1549  * xs_udp_set_buffer_size - set send and receive limits
1550  * @xprt: generic transport
1551  * @sndsize: requested size of send buffer, in bytes
1552  * @rcvsize: requested size of receive buffer, in bytes
1553  *
1554  * Set socket send and receive buffer size limits.
1555  */
1556 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1557 {
1558         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1559
1560         transport->sndsize = 0;
1561         if (sndsize)
1562                 transport->sndsize = sndsize + 1024;
1563         transport->rcvsize = 0;
1564         if (rcvsize)
1565                 transport->rcvsize = rcvsize + 1024;
1566
1567         xs_udp_do_set_buffer_size(xprt);
1568 }
1569
1570 /**
1571  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1572  * @xprt: controlling transport
1573  * @task: task that timed out
1574  *
1575  * Adjust the congestion window after a retransmit timeout has occurred.
1576  */
1577 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1578 {
1579         spin_lock(&xprt->transport_lock);
1580         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1581         spin_unlock(&xprt->transport_lock);
1582 }
1583
1584 static int xs_get_random_port(void)
1585 {
1586         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1587         unsigned short range;
1588         unsigned short rand;
1589
1590         if (max < min)
1591                 return -EADDRINUSE;
1592         range = max - min + 1;
1593         rand = (unsigned short) prandom_u32() % range;
1594         return rand + min;
1595 }
1596
1597 static unsigned short xs_sock_getport(struct socket *sock)
1598 {
1599         struct sockaddr_storage buf;
1600         unsigned short port = 0;
1601
1602         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1603                 goto out;
1604         switch (buf.ss_family) {
1605         case AF_INET6:
1606                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1607                 break;
1608         case AF_INET:
1609                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1610         }
1611 out:
1612         return port;
1613 }
1614
1615 /**
1616  * xs_set_port - reset the port number in the remote endpoint address
1617  * @xprt: generic transport
1618  * @port: new port number
1619  *
1620  */
1621 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1622 {
1623         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1624
1625         rpc_set_port(xs_addr(xprt), port);
1626         xs_update_peer_port(xprt);
1627 }
1628
1629 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1630 {
1631         if (transport->srcport == 0 && transport->xprt.reuseport)
1632                 transport->srcport = xs_sock_getport(sock);
1633 }
1634
1635 static int xs_get_srcport(struct sock_xprt *transport)
1636 {
1637         int port = transport->srcport;
1638
1639         if (port == 0 && transport->xprt.resvport)
1640                 port = xs_get_random_port();
1641         return port;
1642 }
1643
1644 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1645 {
1646         if (transport->srcport != 0)
1647                 transport->srcport = 0;
1648         if (!transport->xprt.resvport)
1649                 return 0;
1650         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1651                 return xprt_max_resvport;
1652         return --port;
1653 }
1654 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1655 {
1656         struct sockaddr_storage myaddr;
1657         int err, nloop = 0;
1658         int port = xs_get_srcport(transport);
1659         unsigned short last;
1660
1661         /*
1662          * If we are asking for any ephemeral port (i.e. port == 0 &&
1663          * transport->xprt.resvport == 0), don't bind.  Let the local
1664          * port selection happen implicitly when the socket is used
1665          * (for example at connect time).
1666          *
1667          * This ensures that we can continue to establish TCP
1668          * connections even when all local ephemeral ports are already
1669          * a part of some TCP connection.  This makes no difference
1670          * for UDP sockets, but also doens't harm them.
1671          *
1672          * If we're asking for any reserved port (i.e. port == 0 &&
1673          * transport->xprt.resvport == 1) xs_get_srcport above will
1674          * ensure that port is non-zero and we will bind as needed.
1675          */
1676         if (port <= 0)
1677                 return port;
1678
1679         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1680         do {
1681                 rpc_set_port((struct sockaddr *)&myaddr, port);
1682                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1683                                 transport->xprt.addrlen);
1684                 if (err == 0) {
1685                         transport->srcport = port;
1686                         break;
1687                 }
1688                 last = port;
1689                 port = xs_next_srcport(transport, port);
1690                 if (port > last)
1691                         nloop++;
1692         } while (err == -EADDRINUSE && nloop != 2);
1693
1694         if (myaddr.ss_family == AF_INET)
1695                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1696                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1697                                 port, err ? "failed" : "ok", err);
1698         else
1699                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1700                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1701                                 port, err ? "failed" : "ok", err);
1702         return err;
1703 }
1704
1705 /*
1706  * We don't support autobind on AF_LOCAL sockets
1707  */
1708 static void xs_local_rpcbind(struct rpc_task *task)
1709 {
1710         xprt_set_bound(task->tk_xprt);
1711 }
1712
1713 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1714 {
1715 }
1716
1717 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1718 static struct lock_class_key xs_key[2];
1719 static struct lock_class_key xs_slock_key[2];
1720
1721 static inline void xs_reclassify_socketu(struct socket *sock)
1722 {
1723         struct sock *sk = sock->sk;
1724
1725         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1726                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1727 }
1728
1729 static inline void xs_reclassify_socket4(struct socket *sock)
1730 {
1731         struct sock *sk = sock->sk;
1732
1733         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1734                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1735 }
1736
1737 static inline void xs_reclassify_socket6(struct socket *sock)
1738 {
1739         struct sock *sk = sock->sk;
1740
1741         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1742                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1743 }
1744
1745 static inline void xs_reclassify_socket(int family, struct socket *sock)
1746 {
1747         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1748                 return;
1749
1750         switch (family) {
1751         case AF_LOCAL:
1752                 xs_reclassify_socketu(sock);
1753                 break;
1754         case AF_INET:
1755                 xs_reclassify_socket4(sock);
1756                 break;
1757         case AF_INET6:
1758                 xs_reclassify_socket6(sock);
1759                 break;
1760         }
1761 }
1762 #else
1763 static inline void xs_reclassify_socket(int family, struct socket *sock)
1764 {
1765 }
1766 #endif
1767
1768 static void xs_dummy_setup_socket(struct work_struct *work)
1769 {
1770 }
1771
1772 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1773                 struct sock_xprt *transport, int family, int type,
1774                 int protocol, bool reuseport)
1775 {
1776         struct file *filp;
1777         struct socket *sock;
1778         int err;
1779
1780         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1781         if (err < 0) {
1782                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1783                                 protocol, -err);
1784                 goto out;
1785         }
1786         xs_reclassify_socket(family, sock);
1787
1788         if (reuseport)
1789                 sock_set_reuseport(sock->sk);
1790
1791         err = xs_bind(transport, sock);
1792         if (err) {
1793                 sock_release(sock);
1794                 goto out;
1795         }
1796
1797         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1798         if (IS_ERR(filp))
1799                 return ERR_CAST(filp);
1800         transport->file = filp;
1801
1802         return sock;
1803 out:
1804         return ERR_PTR(err);
1805 }
1806
1807 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1808                                       struct socket *sock)
1809 {
1810         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1811                                                                         xprt);
1812
1813         if (!transport->inet) {
1814                 struct sock *sk = sock->sk;
1815
1816                 write_lock_bh(&sk->sk_callback_lock);
1817
1818                 xs_save_old_callbacks(transport, sk);
1819
1820                 sk->sk_user_data = xprt;
1821                 sk->sk_data_ready = xs_data_ready;
1822                 sk->sk_write_space = xs_udp_write_space;
1823                 sock_set_flag(sk, SOCK_FASYNC);
1824                 sk->sk_error_report = xs_error_report;
1825
1826                 xprt_clear_connected(xprt);
1827
1828                 /* Reset to new socket */
1829                 transport->sock = sock;
1830                 transport->inet = sk;
1831
1832                 write_unlock_bh(&sk->sk_callback_lock);
1833         }
1834
1835         xs_stream_start_connect(transport);
1836
1837         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1838 }
1839
1840 /**
1841  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1842  * @transport: socket transport to connect
1843  */
1844 static int xs_local_setup_socket(struct sock_xprt *transport)
1845 {
1846         struct rpc_xprt *xprt = &transport->xprt;
1847         struct file *filp;
1848         struct socket *sock;
1849         int status;
1850
1851         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1852                                         SOCK_STREAM, 0, &sock, 1);
1853         if (status < 0) {
1854                 dprintk("RPC:       can't create AF_LOCAL "
1855                         "transport socket (%d).\n", -status);
1856                 goto out;
1857         }
1858         xs_reclassify_socket(AF_LOCAL, sock);
1859
1860         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1861         if (IS_ERR(filp)) {
1862                 status = PTR_ERR(filp);
1863                 goto out;
1864         }
1865         transport->file = filp;
1866
1867         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1868                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1869
1870         status = xs_local_finish_connecting(xprt, sock);
1871         trace_rpc_socket_connect(xprt, sock, status);
1872         switch (status) {
1873         case 0:
1874                 dprintk("RPC:       xprt %p connected to %s\n",
1875                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1876                 xprt->stat.connect_count++;
1877                 xprt->stat.connect_time += (long)jiffies -
1878                                            xprt->stat.connect_start;
1879                 xprt_set_connected(xprt);
1880         case -ENOBUFS:
1881                 break;
1882         case -ENOENT:
1883                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1884                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1885                 break;
1886         case -ECONNREFUSED:
1887                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1888                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1889                 break;
1890         default:
1891                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1892                                 __func__, -status,
1893                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1894         }
1895
1896 out:
1897         xprt_clear_connecting(xprt);
1898         xprt_wake_pending_tasks(xprt, status);
1899         return status;
1900 }
1901
1902 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1903 {
1904         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1905         int ret;
1906
1907          if (RPC_IS_ASYNC(task)) {
1908                 /*
1909                  * We want the AF_LOCAL connect to be resolved in the
1910                  * filesystem namespace of the process making the rpc
1911                  * call.  Thus we connect synchronously.
1912                  *
1913                  * If we want to support asynchronous AF_LOCAL calls,
1914                  * we'll need to figure out how to pass a namespace to
1915                  * connect.
1916                  */
1917                 task->tk_rpc_status = -ENOTCONN;
1918                 rpc_exit(task, -ENOTCONN);
1919                 return;
1920         }
1921         ret = xs_local_setup_socket(transport);
1922         if (ret && !RPC_IS_SOFTCONN(task))
1923                 msleep_interruptible(15000);
1924 }
1925
1926 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1927 /*
1928  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1929  * know that we have exclusive access to the socket), to guard against
1930  * races with xs_reset_transport.
1931  */
1932 static void xs_set_memalloc(struct rpc_xprt *xprt)
1933 {
1934         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1935                         xprt);
1936
1937         /*
1938          * If there's no sock, then we have nothing to set. The
1939          * reconnecting process will get it for us.
1940          */
1941         if (!transport->inet)
1942                 return;
1943         if (atomic_read(&xprt->swapper))
1944                 sk_set_memalloc(transport->inet);
1945 }
1946
1947 /**
1948  * xs_enable_swap - Tag this transport as being used for swap.
1949  * @xprt: transport to tag
1950  *
1951  * Take a reference to this transport on behalf of the rpc_clnt, and
1952  * optionally mark it for swapping if it wasn't already.
1953  */
1954 static int
1955 xs_enable_swap(struct rpc_xprt *xprt)
1956 {
1957         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1958
1959         if (atomic_inc_return(&xprt->swapper) != 1)
1960                 return 0;
1961         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1962                 return -ERESTARTSYS;
1963         if (xs->inet)
1964                 sk_set_memalloc(xs->inet);
1965         xprt_release_xprt(xprt, NULL);
1966         return 0;
1967 }
1968
1969 /**
1970  * xs_disable_swap - Untag this transport as being used for swap.
1971  * @xprt: transport to tag
1972  *
1973  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
1974  * swapper refcount goes to 0, untag the socket as a memalloc socket.
1975  */
1976 static void
1977 xs_disable_swap(struct rpc_xprt *xprt)
1978 {
1979         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1980
1981         if (!atomic_dec_and_test(&xprt->swapper))
1982                 return;
1983         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1984                 return;
1985         if (xs->inet)
1986                 sk_clear_memalloc(xs->inet);
1987         xprt_release_xprt(xprt, NULL);
1988 }
1989 #else
1990 static void xs_set_memalloc(struct rpc_xprt *xprt)
1991 {
1992 }
1993
1994 static int
1995 xs_enable_swap(struct rpc_xprt *xprt)
1996 {
1997         return -EINVAL;
1998 }
1999
2000 static void
2001 xs_disable_swap(struct rpc_xprt *xprt)
2002 {
2003 }
2004 #endif
2005
2006 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2007 {
2008         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2009
2010         if (!transport->inet) {
2011                 struct sock *sk = sock->sk;
2012
2013                 write_lock_bh(&sk->sk_callback_lock);
2014
2015                 xs_save_old_callbacks(transport, sk);
2016
2017                 sk->sk_user_data = xprt;
2018                 sk->sk_data_ready = xs_data_ready;
2019                 sk->sk_write_space = xs_udp_write_space;
2020                 sock_set_flag(sk, SOCK_FASYNC);
2021
2022                 xprt_set_connected(xprt);
2023
2024                 /* Reset to new socket */
2025                 transport->sock = sock;
2026                 transport->inet = sk;
2027
2028                 xs_set_memalloc(xprt);
2029
2030                 write_unlock_bh(&sk->sk_callback_lock);
2031         }
2032         xs_udp_do_set_buffer_size(xprt);
2033
2034         xprt->stat.connect_start = jiffies;
2035 }
2036
2037 static void xs_udp_setup_socket(struct work_struct *work)
2038 {
2039         struct sock_xprt *transport =
2040                 container_of(work, struct sock_xprt, connect_worker.work);
2041         struct rpc_xprt *xprt = &transport->xprt;
2042         struct socket *sock;
2043         int status = -EIO;
2044
2045         sock = xs_create_sock(xprt, transport,
2046                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2047                         IPPROTO_UDP, false);
2048         if (IS_ERR(sock))
2049                 goto out;
2050
2051         dprintk("RPC:       worker connecting xprt %p via %s to "
2052                                 "%s (port %s)\n", xprt,
2053                         xprt->address_strings[RPC_DISPLAY_PROTO],
2054                         xprt->address_strings[RPC_DISPLAY_ADDR],
2055                         xprt->address_strings[RPC_DISPLAY_PORT]);
2056
2057         xs_udp_finish_connecting(xprt, sock);
2058         trace_rpc_socket_connect(xprt, sock, 0);
2059         status = 0;
2060 out:
2061         xprt_clear_connecting(xprt);
2062         xprt_unlock_connect(xprt, transport);
2063         xprt_wake_pending_tasks(xprt, status);
2064 }
2065
2066 /**
2067  * xs_tcp_shutdown - gracefully shut down a TCP socket
2068  * @xprt: transport
2069  *
2070  * Initiates a graceful shutdown of the TCP socket by calling the
2071  * equivalent of shutdown(SHUT_RDWR);
2072  */
2073 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2074 {
2075         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2076         struct socket *sock = transport->sock;
2077         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2078
2079         if (sock == NULL)
2080                 return;
2081         switch (skst) {
2082         default:
2083                 kernel_sock_shutdown(sock, SHUT_RDWR);
2084                 trace_rpc_socket_shutdown(xprt, sock);
2085                 break;
2086         case TCP_CLOSE:
2087         case TCP_TIME_WAIT:
2088                 xs_reset_transport(transport);
2089         }
2090 }
2091
2092 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2093                 struct socket *sock)
2094 {
2095         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2096         unsigned int keepidle;
2097         unsigned int keepcnt;
2098         unsigned int timeo;
2099
2100         spin_lock(&xprt->transport_lock);
2101         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2102         keepcnt = xprt->timeout->to_retries + 1;
2103         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2104                 (xprt->timeout->to_retries + 1);
2105         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2106         spin_unlock(&xprt->transport_lock);
2107
2108         /* TCP Keepalive options */
2109         sock_set_keepalive(sock->sk);
2110         tcp_sock_set_keepidle(sock->sk, keepidle);
2111         tcp_sock_set_keepintvl(sock->sk, keepidle);
2112         tcp_sock_set_keepcnt(sock->sk, keepcnt);
2113
2114         /* TCP user timeout (see RFC5482) */
2115         tcp_sock_set_user_timeout(sock->sk, timeo);
2116 }
2117
2118 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2119                 unsigned long connect_timeout,
2120                 unsigned long reconnect_timeout)
2121 {
2122         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2123         struct rpc_timeout to;
2124         unsigned long initval;
2125
2126         spin_lock(&xprt->transport_lock);
2127         if (reconnect_timeout < xprt->max_reconnect_timeout)
2128                 xprt->max_reconnect_timeout = reconnect_timeout;
2129         if (connect_timeout < xprt->connect_timeout) {
2130                 memcpy(&to, xprt->timeout, sizeof(to));
2131                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2132                 /* Arbitrary lower limit */
2133                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2134                         initval = XS_TCP_INIT_REEST_TO << 1;
2135                 to.to_initval = initval;
2136                 to.to_maxval = initval;
2137                 memcpy(&transport->tcp_timeout, &to,
2138                                 sizeof(transport->tcp_timeout));
2139                 xprt->timeout = &transport->tcp_timeout;
2140                 xprt->connect_timeout = connect_timeout;
2141         }
2142         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2143         spin_unlock(&xprt->transport_lock);
2144 }
2145
2146 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2147 {
2148         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2149         int ret = -ENOTCONN;
2150
2151         if (!transport->inet) {
2152                 struct sock *sk = sock->sk;
2153
2154                 /* Avoid temporary address, they are bad for long-lived
2155                  * connections such as NFS mounts.
2156                  * RFC4941, section 3.6 suggests that:
2157                  *    Individual applications, which have specific
2158                  *    knowledge about the normal duration of connections,
2159                  *    MAY override this as appropriate.
2160                  */
2161                 if (xs_addr(xprt)->sa_family == PF_INET6) {
2162                         ip6_sock_set_addr_preferences(sk,
2163                                 IPV6_PREFER_SRC_PUBLIC);
2164                 }
2165
2166                 xs_tcp_set_socket_timeouts(xprt, sock);
2167
2168                 write_lock_bh(&sk->sk_callback_lock);
2169
2170                 xs_save_old_callbacks(transport, sk);
2171
2172                 sk->sk_user_data = xprt;
2173                 sk->sk_data_ready = xs_data_ready;
2174                 sk->sk_state_change = xs_tcp_state_change;
2175                 sk->sk_write_space = xs_tcp_write_space;
2176                 sock_set_flag(sk, SOCK_FASYNC);
2177                 sk->sk_error_report = xs_error_report;
2178
2179                 /* socket options */
2180                 sock_reset_flag(sk, SOCK_LINGER);
2181                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2182
2183                 xprt_clear_connected(xprt);
2184
2185                 /* Reset to new socket */
2186                 transport->sock = sock;
2187                 transport->inet = sk;
2188
2189                 write_unlock_bh(&sk->sk_callback_lock);
2190         }
2191
2192         if (!xprt_bound(xprt))
2193                 goto out;
2194
2195         xs_set_memalloc(xprt);
2196
2197         xs_stream_start_connect(transport);
2198
2199         /* Tell the socket layer to start connecting... */
2200         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2201         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2202         switch (ret) {
2203         case 0:
2204                 xs_set_srcport(transport, sock);
2205                 /* fall through */
2206         case -EINPROGRESS:
2207                 /* SYN_SENT! */
2208                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2209                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2210                 break;
2211         case -EADDRNOTAVAIL:
2212                 /* Source port number is unavailable. Try a new one! */
2213                 transport->srcport = 0;
2214         }
2215 out:
2216         return ret;
2217 }
2218
2219 /**
2220  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2221  * @work: queued work item
2222  *
2223  * Invoked by a work queue tasklet.
2224  */
2225 static void xs_tcp_setup_socket(struct work_struct *work)
2226 {
2227         struct sock_xprt *transport =
2228                 container_of(work, struct sock_xprt, connect_worker.work);
2229         struct socket *sock = transport->sock;
2230         struct rpc_xprt *xprt = &transport->xprt;
2231         int status = -EIO;
2232
2233         if (!sock) {
2234                 sock = xs_create_sock(xprt, transport,
2235                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2236                                 IPPROTO_TCP, true);
2237                 if (IS_ERR(sock)) {
2238                         status = PTR_ERR(sock);
2239                         goto out;
2240                 }
2241         }
2242
2243         dprintk("RPC:       worker connecting xprt %p via %s to "
2244                                 "%s (port %s)\n", xprt,
2245                         xprt->address_strings[RPC_DISPLAY_PROTO],
2246                         xprt->address_strings[RPC_DISPLAY_ADDR],
2247                         xprt->address_strings[RPC_DISPLAY_PORT]);
2248
2249         status = xs_tcp_finish_connecting(xprt, sock);
2250         trace_rpc_socket_connect(xprt, sock, status);
2251         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2252                         xprt, -status, xprt_connected(xprt),
2253                         sock->sk->sk_state);
2254         switch (status) {
2255         default:
2256                 printk("%s: connect returned unhandled error %d\n",
2257                         __func__, status);
2258                 /* fall through */
2259         case -EADDRNOTAVAIL:
2260                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2261                  * and retry
2262                  */
2263                 xs_tcp_force_close(xprt);
2264                 break;
2265         case 0:
2266         case -EINPROGRESS:
2267         case -EALREADY:
2268                 xprt_unlock_connect(xprt, transport);
2269                 return;
2270         case -EINVAL:
2271                 /* Happens, for instance, if the user specified a link
2272                  * local IPv6 address without a scope-id.
2273                  */
2274         case -ECONNREFUSED:
2275         case -ECONNRESET:
2276         case -ENETDOWN:
2277         case -ENETUNREACH:
2278         case -EHOSTUNREACH:
2279         case -EADDRINUSE:
2280         case -ENOBUFS:
2281                 /*
2282                  * xs_tcp_force_close() wakes tasks with -EIO.
2283                  * We need to wake them first to ensure the
2284                  * correct error code.
2285                  */
2286                 xprt_wake_pending_tasks(xprt, status);
2287                 xs_tcp_force_close(xprt);
2288                 goto out;
2289         }
2290         status = -EAGAIN;
2291 out:
2292         xprt_clear_connecting(xprt);
2293         xprt_unlock_connect(xprt, transport);
2294         xprt_wake_pending_tasks(xprt, status);
2295 }
2296
2297 /**
2298  * xs_connect - connect a socket to a remote endpoint
2299  * @xprt: pointer to transport structure
2300  * @task: address of RPC task that manages state of connect request
2301  *
2302  * TCP: If the remote end dropped the connection, delay reconnecting.
2303  *
2304  * UDP socket connects are synchronous, but we use a work queue anyway
2305  * to guarantee that even unprivileged user processes can set up a
2306  * socket on a privileged port.
2307  *
2308  * If a UDP socket connect fails, the delay behavior here prevents
2309  * retry floods (hard mounts).
2310  */
2311 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2312 {
2313         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2314         unsigned long delay = 0;
2315
2316         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2317
2318         if (transport->sock != NULL) {
2319                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2320                                 "seconds\n",
2321                                 xprt, xprt->reestablish_timeout / HZ);
2322
2323                 /* Start by resetting any existing state */
2324                 xs_reset_transport(transport);
2325
2326                 delay = xprt_reconnect_delay(xprt);
2327                 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2328
2329         } else
2330                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2331
2332         queue_delayed_work(xprtiod_workqueue,
2333                         &transport->connect_worker,
2334                         delay);
2335 }
2336
2337 static void xs_wake_disconnect(struct sock_xprt *transport)
2338 {
2339         if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2340                 xs_tcp_force_close(&transport->xprt);
2341 }
2342
2343 static void xs_wake_write(struct sock_xprt *transport)
2344 {
2345         if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2346                 xprt_write_space(&transport->xprt);
2347 }
2348
2349 static void xs_wake_error(struct sock_xprt *transport)
2350 {
2351         int sockerr;
2352
2353         if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2354                 return;
2355         mutex_lock(&transport->recv_mutex);
2356         if (transport->sock == NULL)
2357                 goto out;
2358         if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2359                 goto out;
2360         sockerr = xchg(&transport->xprt_err, 0);
2361         if (sockerr < 0)
2362                 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2363 out:
2364         mutex_unlock(&transport->recv_mutex);
2365 }
2366
2367 static void xs_wake_pending(struct sock_xprt *transport)
2368 {
2369         if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2370                 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2371 }
2372
2373 static void xs_error_handle(struct work_struct *work)
2374 {
2375         struct sock_xprt *transport = container_of(work,
2376                         struct sock_xprt, error_worker);
2377
2378         xs_wake_disconnect(transport);
2379         xs_wake_write(transport);
2380         xs_wake_error(transport);
2381         xs_wake_pending(transport);
2382 }
2383
2384 /**
2385  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2386  * @xprt: rpc_xprt struct containing statistics
2387  * @seq: output file
2388  *
2389  */
2390 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2391 {
2392         long idle_time = 0;
2393
2394         if (xprt_connected(xprt))
2395                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2396
2397         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2398                         "%llu %llu %lu %llu %llu\n",
2399                         xprt->stat.bind_count,
2400                         xprt->stat.connect_count,
2401                         xprt->stat.connect_time / HZ,
2402                         idle_time,
2403                         xprt->stat.sends,
2404                         xprt->stat.recvs,
2405                         xprt->stat.bad_xids,
2406                         xprt->stat.req_u,
2407                         xprt->stat.bklog_u,
2408                         xprt->stat.max_slots,
2409                         xprt->stat.sending_u,
2410                         xprt->stat.pending_u);
2411 }
2412
2413 /**
2414  * xs_udp_print_stats - display UDP socket-specifc stats
2415  * @xprt: rpc_xprt struct containing statistics
2416  * @seq: output file
2417  *
2418  */
2419 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2420 {
2421         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2422
2423         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2424                         "%lu %llu %llu\n",
2425                         transport->srcport,
2426                         xprt->stat.bind_count,
2427                         xprt->stat.sends,
2428                         xprt->stat.recvs,
2429                         xprt->stat.bad_xids,
2430                         xprt->stat.req_u,
2431                         xprt->stat.bklog_u,
2432                         xprt->stat.max_slots,
2433                         xprt->stat.sending_u,
2434                         xprt->stat.pending_u);
2435 }
2436
2437 /**
2438  * xs_tcp_print_stats - display TCP socket-specifc stats
2439  * @xprt: rpc_xprt struct containing statistics
2440  * @seq: output file
2441  *
2442  */
2443 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2444 {
2445         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2446         long idle_time = 0;
2447
2448         if (xprt_connected(xprt))
2449                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2450
2451         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2452                         "%llu %llu %lu %llu %llu\n",
2453                         transport->srcport,
2454                         xprt->stat.bind_count,
2455                         xprt->stat.connect_count,
2456                         xprt->stat.connect_time / HZ,
2457                         idle_time,
2458                         xprt->stat.sends,
2459                         xprt->stat.recvs,
2460                         xprt->stat.bad_xids,
2461                         xprt->stat.req_u,
2462                         xprt->stat.bklog_u,
2463                         xprt->stat.max_slots,
2464                         xprt->stat.sending_u,
2465                         xprt->stat.pending_u);
2466 }
2467
2468 /*
2469  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2470  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2471  * to use the server side send routines.
2472  */
2473 static int bc_malloc(struct rpc_task *task)
2474 {
2475         struct rpc_rqst *rqst = task->tk_rqstp;
2476         size_t size = rqst->rq_callsize;
2477         struct page *page;
2478         struct rpc_buffer *buf;
2479
2480         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2481                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2482                           size);
2483                 return -EINVAL;
2484         }
2485
2486         page = alloc_page(GFP_KERNEL);
2487         if (!page)
2488                 return -ENOMEM;
2489
2490         buf = page_address(page);
2491         buf->len = PAGE_SIZE;
2492
2493         rqst->rq_buffer = buf->data;
2494         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2495         return 0;
2496 }
2497
2498 /*
2499  * Free the space allocated in the bc_alloc routine
2500  */
2501 static void bc_free(struct rpc_task *task)
2502 {
2503         void *buffer = task->tk_rqstp->rq_buffer;
2504         struct rpc_buffer *buf;
2505
2506         buf = container_of(buffer, struct rpc_buffer, data);
2507         free_page((unsigned long)buf);
2508 }
2509
2510 static int bc_sendto(struct rpc_rqst *req)
2511 {
2512         struct xdr_buf *xdr = &req->rq_snd_buf;
2513         struct sock_xprt *transport =
2514                         container_of(req->rq_xprt, struct sock_xprt, xprt);
2515         struct msghdr msg = {
2516                 .msg_flags      = 0,
2517         };
2518         rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2519                                          (u32)xdr->len);
2520         unsigned int sent = 0;
2521         int err;
2522
2523         req->rq_xtime = ktime_get();
2524         err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2525         xdr_free_bvec(xdr);
2526         if (err < 0 || sent != (xdr->len + sizeof(marker)))
2527                 return -EAGAIN;
2528         return sent;
2529 }
2530
2531 /**
2532  * bc_send_request - Send a backchannel Call on a TCP socket
2533  * @req: rpc_rqst containing Call message to be sent
2534  *
2535  * xpt_mutex ensures @rqstp's whole message is written to the socket
2536  * without interruption.
2537  *
2538  * Return values:
2539  *   %0 if the message was sent successfully
2540  *   %ENOTCONN if the message was not sent
2541  */
2542 static int bc_send_request(struct rpc_rqst *req)
2543 {
2544         struct svc_xprt *xprt;
2545         int len;
2546
2547         /*
2548          * Get the server socket associated with this callback xprt
2549          */
2550         xprt = req->rq_xprt->bc_xprt;
2551
2552         /*
2553          * Grab the mutex to serialize data as the connection is shared
2554          * with the fore channel
2555          */
2556         mutex_lock(&xprt->xpt_mutex);
2557         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2558                 len = -ENOTCONN;
2559         else
2560                 len = bc_sendto(req);
2561         mutex_unlock(&xprt->xpt_mutex);
2562
2563         if (len > 0)
2564                 len = 0;
2565
2566         return len;
2567 }
2568
2569 /*
2570  * The close routine. Since this is client initiated, we do nothing
2571  */
2572
2573 static void bc_close(struct rpc_xprt *xprt)
2574 {
2575         xprt_disconnect_done(xprt);
2576 }
2577
2578 /*
2579  * The xprt destroy routine. Again, because this connection is client
2580  * initiated, we do nothing
2581  */
2582
2583 static void bc_destroy(struct rpc_xprt *xprt)
2584 {
2585         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2586
2587         xs_xprt_free(xprt);
2588         module_put(THIS_MODULE);
2589 }
2590
2591 static const struct rpc_xprt_ops xs_local_ops = {
2592         .reserve_xprt           = xprt_reserve_xprt,
2593         .release_xprt           = xprt_release_xprt,
2594         .alloc_slot             = xprt_alloc_slot,
2595         .free_slot              = xprt_free_slot,
2596         .rpcbind                = xs_local_rpcbind,
2597         .set_port               = xs_local_set_port,
2598         .connect                = xs_local_connect,
2599         .buf_alloc              = rpc_malloc,
2600         .buf_free               = rpc_free,
2601         .prepare_request        = xs_stream_prepare_request,
2602         .send_request           = xs_local_send_request,
2603         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2604         .close                  = xs_close,
2605         .destroy                = xs_destroy,
2606         .print_stats            = xs_local_print_stats,
2607         .enable_swap            = xs_enable_swap,
2608         .disable_swap           = xs_disable_swap,
2609 };
2610
2611 static const struct rpc_xprt_ops xs_udp_ops = {
2612         .set_buffer_size        = xs_udp_set_buffer_size,
2613         .reserve_xprt           = xprt_reserve_xprt_cong,
2614         .release_xprt           = xprt_release_xprt_cong,
2615         .alloc_slot             = xprt_alloc_slot,
2616         .free_slot              = xprt_free_slot,
2617         .rpcbind                = rpcb_getport_async,
2618         .set_port               = xs_set_port,
2619         .connect                = xs_connect,
2620         .buf_alloc              = rpc_malloc,
2621         .buf_free               = rpc_free,
2622         .send_request           = xs_udp_send_request,
2623         .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2624         .timer                  = xs_udp_timer,
2625         .release_request        = xprt_release_rqst_cong,
2626         .close                  = xs_close,
2627         .destroy                = xs_destroy,
2628         .print_stats            = xs_udp_print_stats,
2629         .enable_swap            = xs_enable_swap,
2630         .disable_swap           = xs_disable_swap,
2631         .inject_disconnect      = xs_inject_disconnect,
2632 };
2633
2634 static const struct rpc_xprt_ops xs_tcp_ops = {
2635         .reserve_xprt           = xprt_reserve_xprt,
2636         .release_xprt           = xprt_release_xprt,
2637         .alloc_slot             = xprt_alloc_slot,
2638         .free_slot              = xprt_free_slot,
2639         .rpcbind                = rpcb_getport_async,
2640         .set_port               = xs_set_port,
2641         .connect                = xs_connect,
2642         .buf_alloc              = rpc_malloc,
2643         .buf_free               = rpc_free,
2644         .prepare_request        = xs_stream_prepare_request,
2645         .send_request           = xs_tcp_send_request,
2646         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2647         .close                  = xs_tcp_shutdown,
2648         .destroy                = xs_destroy,
2649         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2650         .print_stats            = xs_tcp_print_stats,
2651         .enable_swap            = xs_enable_swap,
2652         .disable_swap           = xs_disable_swap,
2653         .inject_disconnect      = xs_inject_disconnect,
2654 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2655         .bc_setup               = xprt_setup_bc,
2656         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2657         .bc_num_slots           = xprt_bc_max_slots,
2658         .bc_free_rqst           = xprt_free_bc_rqst,
2659         .bc_destroy             = xprt_destroy_bc,
2660 #endif
2661 };
2662
2663 /*
2664  * The rpc_xprt_ops for the server backchannel
2665  */
2666
2667 static const struct rpc_xprt_ops bc_tcp_ops = {
2668         .reserve_xprt           = xprt_reserve_xprt,
2669         .release_xprt           = xprt_release_xprt,
2670         .alloc_slot             = xprt_alloc_slot,
2671         .free_slot              = xprt_free_slot,
2672         .buf_alloc              = bc_malloc,
2673         .buf_free               = bc_free,
2674         .send_request           = bc_send_request,
2675         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2676         .close                  = bc_close,
2677         .destroy                = bc_destroy,
2678         .print_stats            = xs_tcp_print_stats,
2679         .enable_swap            = xs_enable_swap,
2680         .disable_swap           = xs_disable_swap,
2681         .inject_disconnect      = xs_inject_disconnect,
2682 };
2683
2684 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2685 {
2686         static const struct sockaddr_in sin = {
2687                 .sin_family             = AF_INET,
2688                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2689         };
2690         static const struct sockaddr_in6 sin6 = {
2691                 .sin6_family            = AF_INET6,
2692                 .sin6_addr              = IN6ADDR_ANY_INIT,
2693         };
2694
2695         switch (family) {
2696         case AF_LOCAL:
2697                 break;
2698         case AF_INET:
2699                 memcpy(sap, &sin, sizeof(sin));
2700                 break;
2701         case AF_INET6:
2702                 memcpy(sap, &sin6, sizeof(sin6));
2703                 break;
2704         default:
2705                 dprintk("RPC:       %s: Bad address family\n", __func__);
2706                 return -EAFNOSUPPORT;
2707         }
2708         return 0;
2709 }
2710
2711 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2712                                       unsigned int slot_table_size,
2713                                       unsigned int max_slot_table_size)
2714 {
2715         struct rpc_xprt *xprt;
2716         struct sock_xprt *new;
2717
2718         if (args->addrlen > sizeof(xprt->addr)) {
2719                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2720                 return ERR_PTR(-EBADF);
2721         }
2722
2723         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2724                         max_slot_table_size);
2725         if (xprt == NULL) {
2726                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2727                                 "rpc_xprt\n");
2728                 return ERR_PTR(-ENOMEM);
2729         }
2730
2731         new = container_of(xprt, struct sock_xprt, xprt);
2732         mutex_init(&new->recv_mutex);
2733         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2734         xprt->addrlen = args->addrlen;
2735         if (args->srcaddr)
2736                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2737         else {
2738                 int err;
2739                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2740                                         (struct sockaddr *)&new->srcaddr);
2741                 if (err != 0) {
2742                         xprt_free(xprt);
2743                         return ERR_PTR(err);
2744                 }
2745         }
2746
2747         return xprt;
2748 }
2749
2750 static const struct rpc_timeout xs_local_default_timeout = {
2751         .to_initval = 10 * HZ,
2752         .to_maxval = 10 * HZ,
2753         .to_retries = 2,
2754 };
2755
2756 /**
2757  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2758  * @args: rpc transport creation arguments
2759  *
2760  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2761  */
2762 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2763 {
2764         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2765         struct sock_xprt *transport;
2766         struct rpc_xprt *xprt;
2767         struct rpc_xprt *ret;
2768
2769         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2770                         xprt_max_tcp_slot_table_entries);
2771         if (IS_ERR(xprt))
2772                 return xprt;
2773         transport = container_of(xprt, struct sock_xprt, xprt);
2774
2775         xprt->prot = 0;
2776         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2777
2778         xprt->bind_timeout = XS_BIND_TO;
2779         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2780         xprt->idle_timeout = XS_IDLE_DISC_TO;
2781
2782         xprt->ops = &xs_local_ops;
2783         xprt->timeout = &xs_local_default_timeout;
2784
2785         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2786         INIT_WORK(&transport->error_worker, xs_error_handle);
2787         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2788
2789         switch (sun->sun_family) {
2790         case AF_LOCAL:
2791                 if (sun->sun_path[0] != '/') {
2792                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2793                                         sun->sun_path);
2794                         ret = ERR_PTR(-EINVAL);
2795                         goto out_err;
2796                 }
2797                 xprt_set_bound(xprt);
2798                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2799                 ret = ERR_PTR(xs_local_setup_socket(transport));
2800                 if (ret)
2801                         goto out_err;
2802                 break;
2803         default:
2804                 ret = ERR_PTR(-EAFNOSUPPORT);
2805                 goto out_err;
2806         }
2807
2808         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2809                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2810
2811         if (try_module_get(THIS_MODULE))
2812                 return xprt;
2813         ret = ERR_PTR(-EINVAL);
2814 out_err:
2815         xs_xprt_free(xprt);
2816         return ret;
2817 }
2818
2819 static const struct rpc_timeout xs_udp_default_timeout = {
2820         .to_initval = 5 * HZ,
2821         .to_maxval = 30 * HZ,
2822         .to_increment = 5 * HZ,
2823         .to_retries = 5,
2824 };
2825
2826 /**
2827  * xs_setup_udp - Set up transport to use a UDP socket
2828  * @args: rpc transport creation arguments
2829  *
2830  */
2831 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2832 {
2833         struct sockaddr *addr = args->dstaddr;
2834         struct rpc_xprt *xprt;
2835         struct sock_xprt *transport;
2836         struct rpc_xprt *ret;
2837
2838         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2839                         xprt_udp_slot_table_entries);
2840         if (IS_ERR(xprt))
2841                 return xprt;
2842         transport = container_of(xprt, struct sock_xprt, xprt);
2843
2844         xprt->prot = IPPROTO_UDP;
2845         /* XXX: header size can vary due to auth type, IPv6, etc. */
2846         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2847
2848         xprt->bind_timeout = XS_BIND_TO;
2849         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2850         xprt->idle_timeout = XS_IDLE_DISC_TO;
2851
2852         xprt->ops = &xs_udp_ops;
2853
2854         xprt->timeout = &xs_udp_default_timeout;
2855
2856         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2857         INIT_WORK(&transport->error_worker, xs_error_handle);
2858         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2859
2860         switch (addr->sa_family) {
2861         case AF_INET:
2862                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2863                         xprt_set_bound(xprt);
2864
2865                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2866                 break;
2867         case AF_INET6:
2868                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2869                         xprt_set_bound(xprt);
2870
2871                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2872                 break;
2873         default:
2874                 ret = ERR_PTR(-EAFNOSUPPORT);
2875                 goto out_err;
2876         }
2877
2878         if (xprt_bound(xprt))
2879                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2880                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2881                                 xprt->address_strings[RPC_DISPLAY_PORT],
2882                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2883         else
2884                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2885                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2886                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2887
2888         if (try_module_get(THIS_MODULE))
2889                 return xprt;
2890         ret = ERR_PTR(-EINVAL);
2891 out_err:
2892         xs_xprt_free(xprt);
2893         return ret;
2894 }
2895
2896 static const struct rpc_timeout xs_tcp_default_timeout = {
2897         .to_initval = 60 * HZ,
2898         .to_maxval = 60 * HZ,
2899         .to_retries = 2,
2900 };
2901
2902 /**
2903  * xs_setup_tcp - Set up transport to use a TCP socket
2904  * @args: rpc transport creation arguments
2905  *
2906  */
2907 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2908 {
2909         struct sockaddr *addr = args->dstaddr;
2910         struct rpc_xprt *xprt;
2911         struct sock_xprt *transport;
2912         struct rpc_xprt *ret;
2913         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2914
2915         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2916                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2917
2918         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2919                         max_slot_table_size);
2920         if (IS_ERR(xprt))
2921                 return xprt;
2922         transport = container_of(xprt, struct sock_xprt, xprt);
2923
2924         xprt->prot = IPPROTO_TCP;
2925         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2926
2927         xprt->bind_timeout = XS_BIND_TO;
2928         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2929         xprt->idle_timeout = XS_IDLE_DISC_TO;
2930
2931         xprt->ops = &xs_tcp_ops;
2932         xprt->timeout = &xs_tcp_default_timeout;
2933
2934         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2935         xprt->connect_timeout = xprt->timeout->to_initval *
2936                 (xprt->timeout->to_retries + 1);
2937
2938         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2939         INIT_WORK(&transport->error_worker, xs_error_handle);
2940         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2941
2942         switch (addr->sa_family) {
2943         case AF_INET:
2944                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2945                         xprt_set_bound(xprt);
2946
2947                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2948                 break;
2949         case AF_INET6:
2950                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2951                         xprt_set_bound(xprt);
2952
2953                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2954                 break;
2955         default:
2956                 ret = ERR_PTR(-EAFNOSUPPORT);
2957                 goto out_err;
2958         }
2959
2960         if (xprt_bound(xprt))
2961                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2962                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2963                                 xprt->address_strings[RPC_DISPLAY_PORT],
2964                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2965         else
2966                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2967                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2968                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2969
2970         if (try_module_get(THIS_MODULE))
2971                 return xprt;
2972         ret = ERR_PTR(-EINVAL);
2973 out_err:
2974         xs_xprt_free(xprt);
2975         return ret;
2976 }
2977
2978 /**
2979  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2980  * @args: rpc transport creation arguments
2981  *
2982  */
2983 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2984 {
2985         struct sockaddr *addr = args->dstaddr;
2986         struct rpc_xprt *xprt;
2987         struct sock_xprt *transport;
2988         struct svc_sock *bc_sock;
2989         struct rpc_xprt *ret;
2990
2991         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2992                         xprt_tcp_slot_table_entries);
2993         if (IS_ERR(xprt))
2994                 return xprt;
2995         transport = container_of(xprt, struct sock_xprt, xprt);
2996
2997         xprt->prot = IPPROTO_TCP;
2998         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2999         xprt->timeout = &xs_tcp_default_timeout;
3000
3001         /* backchannel */
3002         xprt_set_bound(xprt);
3003         xprt->bind_timeout = 0;
3004         xprt->reestablish_timeout = 0;
3005         xprt->idle_timeout = 0;
3006
3007         xprt->ops = &bc_tcp_ops;
3008
3009         switch (addr->sa_family) {
3010         case AF_INET:
3011                 xs_format_peer_addresses(xprt, "tcp",
3012                                          RPCBIND_NETID_TCP);
3013                 break;
3014         case AF_INET6:
3015                 xs_format_peer_addresses(xprt, "tcp",
3016                                    RPCBIND_NETID_TCP6);
3017                 break;
3018         default:
3019                 ret = ERR_PTR(-EAFNOSUPPORT);
3020                 goto out_err;
3021         }
3022
3023         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3024                         xprt->address_strings[RPC_DISPLAY_ADDR],
3025                         xprt->address_strings[RPC_DISPLAY_PORT],
3026                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3027
3028         /*
3029          * Once we've associated a backchannel xprt with a connection,
3030          * we want to keep it around as long as the connection lasts,
3031          * in case we need to start using it for a backchannel again;
3032          * this reference won't be dropped until bc_xprt is destroyed.
3033          */
3034         xprt_get(xprt);
3035         args->bc_xprt->xpt_bc_xprt = xprt;
3036         xprt->bc_xprt = args->bc_xprt;
3037         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3038         transport->sock = bc_sock->sk_sock;
3039         transport->inet = bc_sock->sk_sk;
3040
3041         /*
3042          * Since we don't want connections for the backchannel, we set
3043          * the xprt status to connected
3044          */
3045         xprt_set_connected(xprt);
3046
3047         if (try_module_get(THIS_MODULE))
3048                 return xprt;
3049
3050         args->bc_xprt->xpt_bc_xprt = NULL;
3051         args->bc_xprt->xpt_bc_xps = NULL;
3052         xprt_put(xprt);
3053         ret = ERR_PTR(-EINVAL);
3054 out_err:
3055         xs_xprt_free(xprt);
3056         return ret;
3057 }
3058
3059 static struct xprt_class        xs_local_transport = {
3060         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3061         .name           = "named UNIX socket",
3062         .owner          = THIS_MODULE,
3063         .ident          = XPRT_TRANSPORT_LOCAL,
3064         .setup          = xs_setup_local,
3065 };
3066
3067 static struct xprt_class        xs_udp_transport = {
3068         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3069         .name           = "udp",
3070         .owner          = THIS_MODULE,
3071         .ident          = XPRT_TRANSPORT_UDP,
3072         .setup          = xs_setup_udp,
3073 };
3074
3075 static struct xprt_class        xs_tcp_transport = {
3076         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3077         .name           = "tcp",
3078         .owner          = THIS_MODULE,
3079         .ident          = XPRT_TRANSPORT_TCP,
3080         .setup          = xs_setup_tcp,
3081 };
3082
3083 static struct xprt_class        xs_bc_tcp_transport = {
3084         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3085         .name           = "tcp NFSv4.1 backchannel",
3086         .owner          = THIS_MODULE,
3087         .ident          = XPRT_TRANSPORT_BC_TCP,
3088         .setup          = xs_setup_bc_tcp,
3089 };
3090
3091 /**
3092  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3093  *
3094  */
3095 int init_socket_xprt(void)
3096 {
3097         if (!sunrpc_table_header)
3098                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3099
3100         xprt_register_transport(&xs_local_transport);
3101         xprt_register_transport(&xs_udp_transport);
3102         xprt_register_transport(&xs_tcp_transport);
3103         xprt_register_transport(&xs_bc_tcp_transport);
3104
3105         return 0;
3106 }
3107
3108 /**
3109  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3110  *
3111  */
3112 void cleanup_socket_xprt(void)
3113 {
3114         if (sunrpc_table_header) {
3115                 unregister_sysctl_table(sunrpc_table_header);
3116                 sunrpc_table_header = NULL;
3117         }
3118
3119         xprt_unregister_transport(&xs_local_transport);
3120         xprt_unregister_transport(&xs_udp_transport);
3121         xprt_unregister_transport(&xs_tcp_transport);
3122         xprt_unregister_transport(&xs_bc_tcp_transport);
3123 }
3124
3125 static int param_set_uint_minmax(const char *val,
3126                 const struct kernel_param *kp,
3127                 unsigned int min, unsigned int max)
3128 {
3129         unsigned int num;
3130         int ret;
3131
3132         if (!val)
3133                 return -EINVAL;
3134         ret = kstrtouint(val, 0, &num);
3135         if (ret)
3136                 return ret;
3137         if (num < min || num > max)
3138                 return -EINVAL;
3139         *((unsigned int *)kp->arg) = num;
3140         return 0;
3141 }
3142
3143 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3144 {
3145         return param_set_uint_minmax(val, kp,
3146                         RPC_MIN_RESVPORT,
3147                         RPC_MAX_RESVPORT);
3148 }
3149
3150 static const struct kernel_param_ops param_ops_portnr = {
3151         .set = param_set_portnr,
3152         .get = param_get_uint,
3153 };
3154
3155 #define param_check_portnr(name, p) \
3156         __param_check(name, p, unsigned int);
3157
3158 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3159 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3160
3161 static int param_set_slot_table_size(const char *val,
3162                                      const struct kernel_param *kp)
3163 {
3164         return param_set_uint_minmax(val, kp,
3165                         RPC_MIN_SLOT_TABLE,
3166                         RPC_MAX_SLOT_TABLE);
3167 }
3168
3169 static const struct kernel_param_ops param_ops_slot_table_size = {
3170         .set = param_set_slot_table_size,
3171         .get = param_get_uint,
3172 };
3173
3174 #define param_check_slot_table_size(name, p) \
3175         __param_check(name, p, unsigned int);
3176
3177 static int param_set_max_slot_table_size(const char *val,
3178                                      const struct kernel_param *kp)
3179 {
3180         return param_set_uint_minmax(val, kp,
3181                         RPC_MIN_SLOT_TABLE,
3182                         RPC_MAX_SLOT_TABLE_LIMIT);
3183 }
3184
3185 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3186         .set = param_set_max_slot_table_size,
3187         .get = param_get_uint,
3188 };
3189
3190 #define param_check_max_slot_table_size(name, p) \
3191         __param_check(name, p, unsigned int);
3192
3193 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3194                    slot_table_size, 0644);
3195 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3196                    max_slot_table_size, 0644);
3197 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3198                    slot_table_size, 0644);