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 "sunrpc.h"
  58
  59 static void xs_close(struct rpc_xprt *xprt);
  60 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  61                 struct socket *sock);
  62
  63 /*
  64  * xprtsock tunables
  65  */
  66 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  67 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  68 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  69
  70 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  71 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  72
  73 #define XS_TCP_LINGER_TO        (15U * HZ)
  74 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  75
  76 /*
  77  * We can register our own files under /proc/sys/sunrpc by
  78  * calling register_sysctl_table() again.  The files in that
  79  * directory become the union of all files registered there.
  80  *
  81  * We simply need to make sure that we don't collide with
  82  * someone else's file names!
  83  */
  84
  85 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  86 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  87 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  88 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  89 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  90
  91 static struct ctl_table_header *sunrpc_table_header;
  92
  93 /*
  94  * FIXME: changing the UDP slot table size should also resize the UDP
  95  *        socket buffers for existing UDP transports
  96  */
  97 static struct ctl_table xs_tunables_table[] = {
  98         {
  99                 .procname       = "udp_slot_table_entries",
 100                 .data           = &xprt_udp_slot_table_entries,
 101                 .maxlen         = sizeof(unsigned int),
 102                 .mode           = 0644,
 103                 .proc_handler   = proc_dointvec_minmax,
 104                 .extra1         = &min_slot_table_size,
 105                 .extra2         = &max_slot_table_size
 106         },
 107         {
 108                 .procname       = "tcp_slot_table_entries",
 109                 .data           = &xprt_tcp_slot_table_entries,
 110                 .maxlen         = sizeof(unsigned int),
 111                 .mode           = 0644,
 112                 .proc_handler   = proc_dointvec_minmax,
 113                 .extra1         = &min_slot_table_size,
 114                 .extra2         = &max_slot_table_size
 115         },
 116         {
 117                 .procname       = "tcp_max_slot_table_entries",
 118                 .data           = &xprt_max_tcp_slot_table_entries,
 119                 .maxlen         = sizeof(unsigned int),
 120                 .mode           = 0644,
 121                 .proc_handler   = proc_dointvec_minmax,
 122                 .extra1         = &min_slot_table_size,
 123                 .extra2         = &max_tcp_slot_table_limit
 124         },
 125         {
 126                 .procname       = "min_resvport",
 127                 .data           = &xprt_min_resvport,
 128                 .maxlen         = sizeof(unsigned int),
 129                 .mode           = 0644,
 130                 .proc_handler   = proc_dointvec_minmax,
 131                 .extra1         = &xprt_min_resvport_limit,
 132                 .extra2         = &xprt_max_resvport_limit
 133         },
 134         {
 135                 .procname       = "max_resvport",
 136                 .data           = &xprt_max_resvport,
 137                 .maxlen         = sizeof(unsigned int),
 138                 .mode           = 0644,
 139                 .proc_handler   = proc_dointvec_minmax,
 140                 .extra1         = &xprt_min_resvport_limit,
 141                 .extra2         = &xprt_max_resvport_limit
 142         },
 143         {
 144                 .procname       = "tcp_fin_timeout",
 145                 .data           = &xs_tcp_fin_timeout,
 146                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 147                 .mode           = 0644,
 148                 .proc_handler   = proc_dointvec_jiffies,
 149         },
 150         { },
 151 };
 152
 153 static struct ctl_table sunrpc_table[] = {
 154         {
 155                 .procname       = "sunrpc",
 156                 .mode           = 0555,
 157                 .child          = xs_tunables_table
 158         },
 159         { },
 160 };
 161
 162 /*
 163  * Wait duration for a reply from the RPC portmapper.
 164  */
 165 #define XS_BIND_TO              (60U * HZ)
 166
 167 /*
 168  * Delay if a UDP socket connect error occurs.  This is most likely some
 169  * kind of resource problem on the local host.
 170  */
 171 #define XS_UDP_REEST_TO         (2U * HZ)
 172
 173 /*
 174  * The reestablish timeout allows clients to delay for a bit before attempting
 175  * to reconnect to a server that just dropped our connection.
 176  *
 177  * We implement an exponential backoff when trying to reestablish a TCP
 178  * transport connection with the server.  Some servers like to drop a TCP
 179  * connection when they are overworked, so we start with a short timeout and
 180  * increase over time if the server is down or not responding.
 181  */
 182 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 183
 184 /*
 185  * TCP idle timeout; client drops the transport socket if it is idle
 186  * for this long.  Note that we also timeout UDP sockets to prevent
 187  * holding port numbers when there is no RPC traffic.
 188  */
 189 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 190
 191 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 192 # undef  RPC_DEBUG_DATA
 193 # define RPCDBG_FACILITY        RPCDBG_TRANS
 194 #endif
 195
 196 #ifdef RPC_DEBUG_DATA
 197 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 198 {
 199         u8 *buf = (u8 *) packet;
 200         int j;
 201
 202         dprintk("RPC:       %s\n", msg);
 203         for (j = 0; j < count && j < 128; j += 4) {
 204                 if (!(j & 31)) {
 205                         if (j)
 206                                 dprintk("\n");
 207                         dprintk("0x%04x ", j);
 208                 }
 209                 dprintk("%02x%02x%02x%02x ",
 210                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 211         }
 212         dprintk("\n");
 213 }
 214 #else
 215 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 216 {
 217         /* NOP */
 218 }
 219 #endif
 220
 221 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 222 {
 223         return (struct rpc_xprt *) sk->sk_user_data;
 224 }
 225
 226 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 227 {
 228         return (struct sockaddr *) &xprt->addr;
 229 }
 230
 231 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 232 {
 233         return (struct sockaddr_un *) &xprt->addr;
 234 }
 235
 236 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 237 {
 238         return (struct sockaddr_in *) &xprt->addr;
 239 }
 240
 241 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 242 {
 243         return (struct sockaddr_in6 *) &xprt->addr;
 244 }
 245
 246 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 247 {
 248         struct sockaddr *sap = xs_addr(xprt);
 249         struct sockaddr_in6 *sin6;
 250         struct sockaddr_in *sin;
 251         struct sockaddr_un *sun;
 252         char buf[128];
 253
 254         switch (sap->sa_family) {
 255         case AF_LOCAL:
 256                 sun = xs_addr_un(xprt);
 257                 strlcpy(buf, sun->sun_path, sizeof(buf));
 258                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 259                                                 kstrdup(buf, GFP_KERNEL);
 260                 break;
 261         case AF_INET:
 262                 (void)rpc_ntop(sap, buf, sizeof(buf));
 263                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 264                                                 kstrdup(buf, GFP_KERNEL);
 265                 sin = xs_addr_in(xprt);
 266                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 267                 break;
 268         case AF_INET6:
 269                 (void)rpc_ntop(sap, buf, sizeof(buf));
 270                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 271                                                 kstrdup(buf, GFP_KERNEL);
 272                 sin6 = xs_addr_in6(xprt);
 273                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 274                 break;
 275         default:
 276                 BUG();
 277         }
 278
 279         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 280 }
 281
 282 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 283 {
 284         struct sockaddr *sap = xs_addr(xprt);
 285         char buf[128];
 286
 287         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 288         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 289
 290         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 291         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 292 }
 293
 294 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 295                                      const char *protocol,
 296                                      const char *netid)
 297 {
 298         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 299         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 300         xs_format_common_peer_addresses(xprt);
 301         xs_format_common_peer_ports(xprt);
 302 }
 303
 304 static void xs_update_peer_port(struct rpc_xprt *xprt)
 305 {
 306         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 307         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 308
 309         xs_format_common_peer_ports(xprt);
 310 }
 311
 312 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 313 {
 314         unsigned int i;
 315
 316         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 317                 switch (i) {
 318                 case RPC_DISPLAY_PROTO:
 319                 case RPC_DISPLAY_NETID:
 320                         continue;
 321                 default:
 322                         kfree(xprt->address_strings[i]);
 323                 }
 324 }
 325
 326 static size_t
 327 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 328 {
 329         size_t i,n;
 330
 331         if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 332                 return want;
 333         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 334         for (i = 0; i < n; i++) {
 335                 if (buf->pages[i])
 336                         continue;
 337                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 338                 if (!buf->pages[i]) {
 339                         i *= PAGE_SIZE;
 340                         return i > buf->page_base ? i - buf->page_base : 0;
 341                 }
 342         }
 343         return want;
 344 }
 345
 346 static ssize_t
 347 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 348 {
 349         ssize_t ret;
 350         if (seek != 0)
 351                 iov_iter_advance(&msg->msg_iter, seek);
 352         ret = sock_recvmsg(sock, msg, flags);
 353         return ret > 0 ? ret + seek : ret;
 354 }
 355
 356 static ssize_t
 357 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 358                 struct kvec *kvec, size_t count, size_t seek)
 359 {
 360         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 361         return xs_sock_recvmsg(sock, msg, flags, seek);
 362 }
 363
 364 static ssize_t
 365 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 366                 struct bio_vec *bvec, unsigned long nr, size_t count,
 367                 size_t seek)
 368 {
 369         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 370         return xs_sock_recvmsg(sock, msg, flags, seek);
 371 }
 372
 373 static ssize_t
 374 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 375                 size_t count)
 376 {
 377         iov_iter_discard(&msg->msg_iter, READ, count);
 378         return sock_recvmsg(sock, msg, flags);
 379 }
 380
 381 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 382 static void
 383 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 384 {
 385         struct bvec_iter bi = {
 386                 .bi_size = count,
 387         };
 388         struct bio_vec bv;
 389
 390         bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 391         for_each_bvec(bv, bvec, bi, bi)
 392                 flush_dcache_page(bv.bv_page);
 393 }
 394 #else
 395 static inline void
 396 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 397 {
 398 }
 399 #endif
 400
 401 static ssize_t
 402 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 403                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 404 {
 405         size_t want, seek_init = seek, offset = 0;
 406         ssize_t ret;
 407
 408         want = min_t(size_t, count, buf->head[0].iov_len);
 409         if (seek < want) {
 410                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 411                 if (ret <= 0)
 412                         goto sock_err;
 413                 offset += ret;
 414                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 415                         goto out;
 416                 if (ret != want)
 417                         goto out;
 418                 seek = 0;
 419         } else {
 420                 seek -= want;
 421                 offset += want;
 422         }
 423
 424         want = xs_alloc_sparse_pages(buf,
 425                         min_t(size_t, count - offset, buf->page_len),
 426                         GFP_KERNEL);
 427         if (seek < want) {
 428                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 429                                 xdr_buf_pagecount(buf),
 430                                 want + buf->page_base,
 431                                 seek + buf->page_base);
 432                 if (ret <= 0)
 433                         goto sock_err;
 434                 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 435                 offset += ret - buf->page_base;
 436                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 437                         goto out;
 438                 if (ret != want)
 439                         goto out;
 440                 seek = 0;
 441         } else {
 442                 seek -= want;
 443                 offset += want;
 444         }
 445
 446         want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 447         if (seek < want) {
 448                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 449                 if (ret <= 0)
 450                         goto sock_err;
 451                 offset += ret;
 452                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 453                         goto out;
 454                 if (ret != want)
 455                         goto out;
 456         } else if (offset < seek_init)
 457                 offset = seek_init;
 458         ret = -EMSGSIZE;
 459 out:
 460         *read = offset - seek_init;
 461         return ret;
 462 sock_err:
 463         offset += seek;
 464         goto out;
 465 }
 466
 467 static void
 468 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 469 {
 470         if (!transport->recv.copied) {
 471                 if (buf->head[0].iov_len >= transport->recv.offset)
 472                         memcpy(buf->head[0].iov_base,
 473                                         &transport->recv.xid,
 474                                         transport->recv.offset);
 475                 transport->recv.copied = transport->recv.offset;
 476         }
 477 }
 478
 479 static bool
 480 xs_read_stream_request_done(struct sock_xprt *transport)
 481 {
 482         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 483 }
 484
 485 static void
 486 xs_read_stream_check_eor(struct sock_xprt *transport,
 487                 struct msghdr *msg)
 488 {
 489         if (xs_read_stream_request_done(transport))
 490                 msg->msg_flags |= MSG_EOR;
 491 }
 492
 493 static ssize_t
 494 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 495                 int flags, struct rpc_rqst *req)
 496 {
 497         struct xdr_buf *buf = &req->rq_private_buf;
 498         size_t want, uninitialized_var(read);
 499         ssize_t uninitialized_var(ret);
 500
 501         xs_read_header(transport, buf);
 502
 503         want = transport->recv.len - transport->recv.offset;
 504         if (want != 0) {
 505                 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 506                                 transport->recv.copied + want,
 507                                 transport->recv.copied,
 508                                 &read);
 509                 transport->recv.offset += read;
 510                 transport->recv.copied += read;
 511         }
 512
 513         if (transport->recv.offset == transport->recv.len)
 514                 xs_read_stream_check_eor(transport, msg);
 515
 516         if (want == 0)
 517                 return 0;
 518
 519         switch (ret) {
 520         default:
 521                 break;
 522         case -EFAULT:
 523         case -EMSGSIZE:
 524                 msg->msg_flags |= MSG_TRUNC;
 525                 return read;
 526         case 0:
 527                 return -ESHUTDOWN;
 528         }
 529         return ret < 0 ? ret : read;
 530 }
 531
 532 static size_t
 533 xs_read_stream_headersize(bool isfrag)
 534 {
 535         if (isfrag)
 536                 return sizeof(__be32);
 537         return 3 * sizeof(__be32);
 538 }
 539
 540 static ssize_t
 541 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 542                 int flags, size_t want, size_t seek)
 543 {
 544         struct kvec kvec = {
 545                 .iov_base = &transport->recv.fraghdr,
 546                 .iov_len = want,
 547         };
 548         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 549 }
 550
 551 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 552 static ssize_t
 553 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 554 {
 555         struct rpc_xprt *xprt = &transport->xprt;
 556         struct rpc_rqst *req;
 557         ssize_t ret;
 558
 559         /* Look up and lock the request corresponding to the given XID */
 560         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 561         if (!req) {
 562                 printk(KERN_WARNING "Callback slot table overflowed\n");
 563                 return -ESHUTDOWN;
 564         }
 565
 566         ret = xs_read_stream_request(transport, msg, flags, req);
 567         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 568                 xprt_complete_bc_request(req, transport->recv.copied);
 569
 570         return ret;
 571 }
 572 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 573 static ssize_t
 574 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 575 {
 576         return -ESHUTDOWN;
 577 }
 578 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 579
 580 static ssize_t
 581 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 582 {
 583         struct rpc_xprt *xprt = &transport->xprt;
 584         struct rpc_rqst *req;
 585         ssize_t ret = 0;
 586
 587         /* Look up and lock the request corresponding to the given XID */
 588         spin_lock(&xprt->queue_lock);
 589         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 590         if (!req) {
 591                 msg->msg_flags |= MSG_TRUNC;
 592                 goto out;
 593         }
 594         xprt_pin_rqst(req);
 595         spin_unlock(&xprt->queue_lock);
 596
 597         ret = xs_read_stream_request(transport, msg, flags, req);
 598
 599         spin_lock(&xprt->queue_lock);
 600         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 601                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 602         xprt_unpin_rqst(req);
 603 out:
 604         spin_unlock(&xprt->queue_lock);
 605         return ret;
 606 }
 607
 608 static ssize_t
 609 xs_read_stream(struct sock_xprt *transport, int flags)
 610 {
 611         struct msghdr msg = { 0 };
 612         size_t want, read = 0;
 613         ssize_t ret = 0;
 614
 615         if (transport->recv.len == 0) {
 616                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 617                 ret = xs_read_stream_header(transport, &msg, flags, want,
 618                                 transport->recv.offset);
 619                 if (ret <= 0)
 620                         goto out_err;
 621                 transport->recv.offset = ret;
 622                 if (transport->recv.offset != want)
 623                         return transport->recv.offset;
 624                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 625                         RPC_FRAGMENT_SIZE_MASK;
 626                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 627                 read = ret;
 628         }
 629
 630         switch (be32_to_cpu(transport->recv.calldir)) {
 631         default:
 632                 msg.msg_flags |= MSG_TRUNC;
 633                 break;
 634         case RPC_CALL:
 635                 ret = xs_read_stream_call(transport, &msg, flags);
 636                 break;
 637         case RPC_REPLY:
 638                 ret = xs_read_stream_reply(transport, &msg, flags);
 639         }
 640         if (msg.msg_flags & MSG_TRUNC) {
 641                 transport->recv.calldir = cpu_to_be32(-1);
 642                 transport->recv.copied = -1;
 643         }
 644         if (ret < 0)
 645                 goto out_err;
 646         read += ret;
 647         if (transport->recv.offset < transport->recv.len) {
 648                 if (!(msg.msg_flags & MSG_TRUNC))
 649                         return read;
 650                 msg.msg_flags = 0;
 651                 ret = xs_read_discard(transport->sock, &msg, flags,
 652                                 transport->recv.len - transport->recv.offset);
 653                 if (ret <= 0)
 654                         goto out_err;
 655                 transport->recv.offset += ret;
 656                 read += ret;
 657                 if (transport->recv.offset != transport->recv.len)
 658                         return read;
 659         }
 660         if (xs_read_stream_request_done(transport)) {
 661                 trace_xs_stream_read_request(transport);
 662                 transport->recv.copied = 0;
 663         }
 664         transport->recv.offset = 0;
 665         transport->recv.len = 0;
 666         return read;
 667 out_err:
 668         return ret != 0 ? ret : -ESHUTDOWN;
 669 }
 670
 671 static __poll_t xs_poll_socket(struct sock_xprt *transport)
 672 {
 673         return transport->sock->ops->poll(transport->file, transport->sock,
 674                         NULL);
 675 }
 676
 677 static bool xs_poll_socket_readable(struct sock_xprt *transport)
 678 {
 679         __poll_t events = xs_poll_socket(transport);
 680
 681         return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 682 }
 683
 684 static void xs_poll_check_readable(struct sock_xprt *transport)
 685 {
 686
 687         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 688         if (!xs_poll_socket_readable(transport))
 689                 return;
 690         if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 691                 queue_work(xprtiod_workqueue, &transport->recv_worker);
 692 }
 693
 694 static void xs_stream_data_receive(struct sock_xprt *transport)
 695 {
 696         size_t read = 0;
 697         ssize_t ret = 0;
 698
 699         mutex_lock(&transport->recv_mutex);
 700         if (transport->sock == NULL)
 701                 goto out;
 702         for (;;) {
 703                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 704                 if (ret < 0)
 705                         break;
 706                 read += ret;
 707                 cond_resched();
 708         }
 709         if (ret == -ESHUTDOWN)
 710                 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 711         else
 712                 xs_poll_check_readable(transport);
 713 out:
 714         mutex_unlock(&transport->recv_mutex);
 715         trace_xs_stream_read_data(&transport->xprt, ret, read);
 716 }
 717
 718 static void xs_stream_data_receive_workfn(struct work_struct *work)
 719 {
 720         struct sock_xprt *transport =
 721                 container_of(work, struct sock_xprt, recv_worker);
 722         unsigned int pflags = memalloc_nofs_save();
 723
 724         xs_stream_data_receive(transport);
 725         memalloc_nofs_restore(pflags);
 726 }
 727
 728 static void
 729 xs_stream_reset_connect(struct sock_xprt *transport)
 730 {
 731         transport->recv.offset = 0;
 732         transport->recv.len = 0;
 733         transport->recv.copied = 0;
 734         transport->xmit.offset = 0;
 735 }
 736
 737 static void
 738 xs_stream_start_connect(struct sock_xprt *transport)
 739 {
 740         transport->xprt.stat.connect_count++;
 741         transport->xprt.stat.connect_start = jiffies;
 742 }
 743
 744 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 745
 746 static int xs_sendmsg(struct socket *sock, struct msghdr *msg, size_t seek)
 747 {
 748         if (seek)
 749                 iov_iter_advance(&msg->msg_iter, seek);
 750         return sock_sendmsg(sock, msg);
 751 }
 752
 753 static int xs_send_kvec(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t seek)
 754 {
 755         iov_iter_kvec(&msg->msg_iter, WRITE, vec, 1, vec->iov_len);
 756         return xs_sendmsg(sock, msg, seek);
 757 }
 758
 759 static int xs_send_pagedata(struct socket *sock, struct msghdr *msg, struct xdr_buf *xdr, size_t base)
 760 {
 761         int err;
 762
 763         err = xdr_alloc_bvec(xdr, GFP_KERNEL);
 764         if (err < 0)
 765                 return err;
 766
 767         iov_iter_bvec(&msg->msg_iter, WRITE, xdr->bvec,
 768                         xdr_buf_pagecount(xdr),
 769                         xdr->page_len + xdr->page_base);
 770         return xs_sendmsg(sock, msg, base + xdr->page_base);
 771 }
 772
 773 #define xs_record_marker_len() sizeof(rpc_fraghdr)
 774
 775 /* Common case:
 776  *  - stream transport
 777  *  - sending from byte 0 of the message
 778  *  - the message is wholly contained in @xdr's head iovec
 779  */
 780 static int xs_send_rm_and_kvec(struct socket *sock, struct msghdr *msg,
 781                 rpc_fraghdr marker, struct kvec *vec, size_t base)
 782 {
 783         struct kvec iov[2] = {
 784                 [0] = {
 785                         .iov_base       = &marker,
 786                         .iov_len        = sizeof(marker)
 787                 },
 788                 [1] = *vec,
 789         };
 790         size_t len = iov[0].iov_len + iov[1].iov_len;
 791
 792         iov_iter_kvec(&msg->msg_iter, WRITE, iov, 2, len);
 793         return xs_sendmsg(sock, msg, base);
 794 }
 795
 796 /**
 797  * xs_sendpages - write pages directly to a socket
 798  * @sock: socket to send on
 799  * @addr: UDP only -- address of destination
 800  * @addrlen: UDP only -- length of destination address
 801  * @xdr: buffer containing this request
 802  * @base: starting position in the buffer
 803  * @rm: stream record marker field
 804  * @sent_p: return the total number of bytes successfully queued for sending
 805  *
 806  */
 807 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, rpc_fraghdr rm, int *sent_p)
 808 {
 809         struct msghdr msg = {
 810                 .msg_name = addr,
 811                 .msg_namelen = addrlen,
 812                 .msg_flags = XS_SENDMSG_FLAGS | MSG_MORE,
 813         };
 814         unsigned int rmsize = rm ? sizeof(rm) : 0;
 815         unsigned int remainder = rmsize + xdr->len - base;
 816         unsigned int want;
 817         int err = 0;
 818
 819         if (unlikely(!sock))
 820                 return -ENOTSOCK;
 821
 822         want = xdr->head[0].iov_len + rmsize;
 823         if (base < want) {
 824                 unsigned int len = want - base;
 825                 remainder -= len;
 826                 if (remainder == 0)
 827                         msg.msg_flags &= ~MSG_MORE;
 828                 if (rmsize)
 829                         err = xs_send_rm_and_kvec(sock, &msg, rm,
 830                                         &xdr->head[0], base);
 831                 else
 832                         err = xs_send_kvec(sock, &msg, &xdr->head[0], base);
 833                 if (remainder == 0 || err != len)
 834                         goto out;
 835                 *sent_p += err;
 836                 base = 0;
 837         } else
 838                 base -= want;
 839
 840         if (base < xdr->page_len) {
 841                 unsigned int len = xdr->page_len - base;
 842                 remainder -= len;
 843                 if (remainder == 0)
 844                         msg.msg_flags &= ~MSG_MORE;
 845                 err = xs_send_pagedata(sock, &msg, xdr, base);
 846                 if (remainder == 0 || err != len)
 847                         goto out;
 848                 *sent_p += err;
 849                 base = 0;
 850         } else
 851                 base -= xdr->page_len;
 852
 853         if (base >= xdr->tail[0].iov_len)
 854                 return 0;
 855         msg.msg_flags &= ~MSG_MORE;
 856         err = xs_send_kvec(sock, &msg, &xdr->tail[0], base);
 857 out:
 858         if (err > 0) {
 859                 *sent_p += err;
 860                 err = 0;
 861         }
 862         return err;
 863 }
 864
 865 /**
 866  * xs_nospace - handle transmit was incomplete
 867  * @req: pointer to RPC request
 868  *
 869  */
 870 static int xs_nospace(struct rpc_rqst *req)
 871 {
 872         struct rpc_xprt *xprt = req->rq_xprt;
 873         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 874         struct sock *sk = transport->inet;
 875         int ret = -EAGAIN;
 876
 877         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 878                         req->rq_task->tk_pid,
 879                         req->rq_slen - transport->xmit.offset,
 880                         req->rq_slen);
 881
 882         /* Protect against races with write_space */
 883         spin_lock(&xprt->transport_lock);
 884
 885         /* Don't race with disconnect */
 886         if (xprt_connected(xprt)) {
 887                 /* wait for more buffer space */
 888                 sk->sk_write_pending++;
 889                 xprt_wait_for_buffer_space(xprt);
 890         } else
 891                 ret = -ENOTCONN;
 892
 893         spin_unlock(&xprt->transport_lock);
 894
 895         /* Race breaker in case memory is freed before above code is called */
 896         if (ret == -EAGAIN) {
 897                 struct socket_wq *wq;
 898
 899                 rcu_read_lock();
 900                 wq = rcu_dereference(sk->sk_wq);
 901                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 902                 rcu_read_unlock();
 903
 904                 sk->sk_write_space(sk);
 905         }
 906         return ret;
 907 }
 908
 909 static void
 910 xs_stream_prepare_request(struct rpc_rqst *req)
 911 {
 912         xdr_free_bvec(&req->rq_rcv_buf);
 913         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 914 }
 915
 916 /*
 917  * Determine if the previous message in the stream was aborted before it
 918  * could complete transmission.
 919  */
 920 static bool
 921 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 922 {
 923         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 924 }
 925
 926 /*
 927  * Return the stream record marker field for a record of length < 2^31-1
 928  */
 929 static rpc_fraghdr
 930 xs_stream_record_marker(struct xdr_buf *xdr)
 931 {
 932         if (!xdr->len)
 933                 return 0;
 934         return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 935 }
 936
 937 /**
 938  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 939  * @req: pointer to RPC request
 940  *
 941  * Return values:
 942  *        0:    The request has been sent
 943  *   EAGAIN:    The socket was blocked, please call again later to
 944  *              complete the request
 945  * ENOTCONN:    Caller needs to invoke connect logic then call again
 946  *    other:    Some other error occured, the request was not sent
 947  */
 948 static int xs_local_send_request(struct rpc_rqst *req)
 949 {
 950         struct rpc_xprt *xprt = req->rq_xprt;
 951         struct sock_xprt *transport =
 952                                 container_of(xprt, struct sock_xprt, xprt);
 953         struct xdr_buf *xdr = &req->rq_snd_buf;
 954         rpc_fraghdr rm = xs_stream_record_marker(xdr);
 955         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 956         int status;
 957         int sent = 0;
 958
 959         /* Close the stream if the previous transmission was incomplete */
 960         if (xs_send_request_was_aborted(transport, req)) {
 961                 xs_close(xprt);
 962                 return -ENOTCONN;
 963         }
 964
 965         xs_pktdump("packet data:",
 966                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 967
 968         req->rq_xtime = ktime_get();
 969         status = xs_sendpages(transport->sock, NULL, 0, xdr,
 970                               transport->xmit.offset, rm, &sent);
 971         dprintk("RPC:       %s(%u) = %d\n",
 972                         __func__, xdr->len - transport->xmit.offset, status);
 973
 974         if (status == -EAGAIN && sock_writeable(transport->inet))
 975                 status = -ENOBUFS;
 976
 977         if (likely(sent > 0) || status == 0) {
 978                 transport->xmit.offset += sent;
 979                 req->rq_bytes_sent = transport->xmit.offset;
 980                 if (likely(req->rq_bytes_sent >= msglen)) {
 981                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 982                         transport->xmit.offset = 0;
 983                         return 0;
 984                 }
 985                 status = -EAGAIN;
 986         }
 987
 988         switch (status) {
 989         case -ENOBUFS:
 990                 break;
 991         case -EAGAIN:
 992                 status = xs_nospace(req);
 993                 break;
 994         default:
 995                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 996                         -status);
 997                 /* fall through */
 998         case -EPIPE:
 999                 xs_close(xprt);
1000                 status = -ENOTCONN;
1001         }
1002
1003         return status;
1004 }
1005
1006 /**
1007  * xs_udp_send_request - write an RPC request to a UDP socket
1008  * @req: pointer to RPC request
1009  *
1010  * Return values:
1011  *        0:    The request has been sent
1012  *   EAGAIN:    The socket was blocked, please call again later to
1013  *              complete the request
1014  * ENOTCONN:    Caller needs to invoke connect logic then call again
1015  *    other:    Some other error occurred, the request was not sent
1016  */
1017 static int xs_udp_send_request(struct rpc_rqst *req)
1018 {
1019         struct rpc_xprt *xprt = req->rq_xprt;
1020         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1021         struct xdr_buf *xdr = &req->rq_snd_buf;
1022         int sent = 0;
1023         int status;
1024
1025         xs_pktdump("packet data:",
1026                                 req->rq_svec->iov_base,
1027                                 req->rq_svec->iov_len);
1028
1029         if (!xprt_bound(xprt))
1030                 return -ENOTCONN;
1031
1032         if (!xprt_request_get_cong(xprt, req))
1033                 return -EBADSLT;
1034
1035         req->rq_xtime = ktime_get();
1036         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
1037                               xdr, 0, 0, &sent);
1038
1039         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
1040                         xdr->len, status);
1041
1042         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
1043         if (status == -EPERM)
1044                 goto process_status;
1045
1046         if (status == -EAGAIN && sock_writeable(transport->inet))
1047                 status = -ENOBUFS;
1048
1049         if (sent > 0 || status == 0) {
1050                 req->rq_xmit_bytes_sent += sent;
1051                 if (sent >= req->rq_slen)
1052                         return 0;
1053                 /* Still some bytes left; set up for a retry later. */
1054                 status = -EAGAIN;
1055         }
1056
1057 process_status:
1058         switch (status) {
1059         case -ENOTSOCK:
1060                 status = -ENOTCONN;
1061                 /* Should we call xs_close() here? */
1062                 break;
1063         case -EAGAIN:
1064                 status = xs_nospace(req);
1065                 break;
1066         case -ENETUNREACH:
1067         case -ENOBUFS:
1068         case -EPIPE:
1069         case -ECONNREFUSED:
1070         case -EPERM:
1071                 /* When the server has died, an ICMP port unreachable message
1072                  * prompts ECONNREFUSED. */
1073                 break;
1074         default:
1075                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1076                         -status);
1077         }
1078
1079         return status;
1080 }
1081
1082 /**
1083  * xs_tcp_send_request - write an RPC request to a TCP socket
1084  * @req: pointer to RPC request
1085  *
1086  * Return values:
1087  *        0:    The request has been sent
1088  *   EAGAIN:    The socket was blocked, please call again later to
1089  *              complete the request
1090  * ENOTCONN:    Caller needs to invoke connect logic then call again
1091  *    other:    Some other error occurred, the request was not sent
1092  *
1093  * XXX: In the case of soft timeouts, should we eventually give up
1094  *      if sendmsg is not able to make progress?
1095  */
1096 static int xs_tcp_send_request(struct rpc_rqst *req)
1097 {
1098         struct rpc_xprt *xprt = req->rq_xprt;
1099         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1100         struct xdr_buf *xdr = &req->rq_snd_buf;
1101         rpc_fraghdr rm = xs_stream_record_marker(xdr);
1102         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1103         bool vm_wait = false;
1104         int status;
1105         int sent;
1106
1107         /* Close the stream if the previous transmission was incomplete */
1108         if (xs_send_request_was_aborted(transport, req)) {
1109                 if (transport->sock != NULL)
1110                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1111                 return -ENOTCONN;
1112         }
1113
1114         xs_pktdump("packet data:",
1115                                 req->rq_svec->iov_base,
1116                                 req->rq_svec->iov_len);
1117
1118         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1119                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1120
1121         /* Continue transmitting the packet/record. We must be careful
1122          * to cope with writespace callbacks arriving _after_ we have
1123          * called sendmsg(). */
1124         req->rq_xtime = ktime_get();
1125         while (1) {
1126                 sent = 0;
1127                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1128                                       transport->xmit.offset, rm, &sent);
1129
1130                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1131                                 xdr->len - transport->xmit.offset, status);
1132
1133                 /* If we've sent the entire packet, immediately
1134                  * reset the count of bytes sent. */
1135                 transport->xmit.offset += sent;
1136                 req->rq_bytes_sent = transport->xmit.offset;
1137                 if (likely(req->rq_bytes_sent >= msglen)) {
1138                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1139                         transport->xmit.offset = 0;
1140                         return 0;
1141                 }
1142
1143                 WARN_ON_ONCE(sent == 0 && status == 0);
1144
1145                 if (status == -EAGAIN ) {
1146                         /*
1147                          * Return EAGAIN if we're sure we're hitting the
1148                          * socket send buffer limits.
1149                          */
1150                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1151                                 break;
1152                         /*
1153                          * Did we hit a memory allocation failure?
1154                          */
1155                         if (sent == 0) {
1156                                 status = -ENOBUFS;
1157                                 if (vm_wait)
1158                                         break;
1159                                 /* Retry, knowing now that we're below the
1160                                  * socket send buffer limit
1161                                  */
1162                                 vm_wait = true;
1163                         }
1164                         continue;
1165                 }
1166                 if (status < 0)
1167                         break;
1168                 vm_wait = false;
1169         }
1170
1171         switch (status) {
1172         case -ENOTSOCK:
1173                 status = -ENOTCONN;
1174                 /* Should we call xs_close() here? */
1175                 break;
1176         case -EAGAIN:
1177                 status = xs_nospace(req);
1178                 break;
1179         case -ECONNRESET:
1180         case -ECONNREFUSED:
1181         case -ENOTCONN:
1182         case -EADDRINUSE:
1183         case -ENOBUFS:
1184         case -EPIPE:
1185                 break;
1186         default:
1187                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1188                         -status);
1189         }
1190
1191         return status;
1192 }
1193
1194 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1195 {
1196         transport->old_data_ready = sk->sk_data_ready;
1197         transport->old_state_change = sk->sk_state_change;
1198         transport->old_write_space = sk->sk_write_space;
1199         transport->old_error_report = sk->sk_error_report;
1200 }
1201
1202 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1203 {
1204         sk->sk_data_ready = transport->old_data_ready;
1205         sk->sk_state_change = transport->old_state_change;
1206         sk->sk_write_space = transport->old_write_space;
1207         sk->sk_error_report = transport->old_error_report;
1208 }
1209
1210 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1211 {
1212         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1213
1214         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1215         clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1216         clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1217         clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1218 }
1219
1220 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1221 {
1222         set_bit(nr, &transport->sock_state);
1223         queue_work(xprtiod_workqueue, &transport->error_worker);
1224 }
1225
1226 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1227 {
1228         smp_mb__before_atomic();
1229         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1230         clear_bit(XPRT_CLOSING, &xprt->state);
1231         xs_sock_reset_state_flags(xprt);
1232         smp_mb__after_atomic();
1233 }
1234
1235 /**
1236  * xs_error_report - callback to handle TCP socket state errors
1237  * @sk: socket
1238  *
1239  * Note: we don't call sock_error() since there may be a rpc_task
1240  * using the socket, and so we don't want to clear sk->sk_err.
1241  */
1242 static void xs_error_report(struct sock *sk)
1243 {
1244         struct sock_xprt *transport;
1245         struct rpc_xprt *xprt;
1246         int err;
1247
1248         read_lock_bh(&sk->sk_callback_lock);
1249         if (!(xprt = xprt_from_sock(sk)))
1250                 goto out;
1251
1252         transport = container_of(xprt, struct sock_xprt, xprt);
1253         err = -sk->sk_err;
1254         if (err == 0)
1255                 goto out;
1256         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1257                         xprt, -err);
1258         trace_rpc_socket_error(xprt, sk->sk_socket, err);
1259         xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1260  out:
1261         read_unlock_bh(&sk->sk_callback_lock);
1262 }
1263
1264 static void xs_reset_transport(struct sock_xprt *transport)
1265 {
1266         struct socket *sock = transport->sock;
1267         struct sock *sk = transport->inet;
1268         struct rpc_xprt *xprt = &transport->xprt;
1269         struct file *filp = transport->file;
1270
1271         if (sk == NULL)
1272                 return;
1273
1274         if (atomic_read(&transport->xprt.swapper))
1275                 sk_clear_memalloc(sk);
1276
1277         kernel_sock_shutdown(sock, SHUT_RDWR);
1278
1279         mutex_lock(&transport->recv_mutex);
1280         write_lock_bh(&sk->sk_callback_lock);
1281         transport->inet = NULL;
1282         transport->sock = NULL;
1283         transport->file = NULL;
1284
1285         sk->sk_user_data = NULL;
1286
1287         xs_restore_old_callbacks(transport, sk);
1288         xprt_clear_connected(xprt);
1289         write_unlock_bh(&sk->sk_callback_lock);
1290         xs_sock_reset_connection_flags(xprt);
1291         /* Reset stream record info */
1292         xs_stream_reset_connect(transport);
1293         mutex_unlock(&transport->recv_mutex);
1294
1295         trace_rpc_socket_close(xprt, sock);
1296         fput(filp);
1297
1298         xprt_disconnect_done(xprt);
1299 }
1300
1301 /**
1302  * xs_close - close a socket
1303  * @xprt: transport
1304  *
1305  * This is used when all requests are complete; ie, no DRC state remains
1306  * on the server we want to save.
1307  *
1308  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1309  * xs_reset_transport() zeroing the socket from underneath a writer.
1310  */
1311 static void xs_close(struct rpc_xprt *xprt)
1312 {
1313         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1314
1315         dprintk("RPC:       xs_close xprt %p\n", xprt);
1316
1317         xs_reset_transport(transport);
1318         xprt->reestablish_timeout = 0;
1319 }
1320
1321 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1322 {
1323         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1324                 xprt);
1325         xprt_disconnect_done(xprt);
1326 }
1327
1328 static void xs_xprt_free(struct rpc_xprt *xprt)
1329 {
1330         xs_free_peer_addresses(xprt);
1331         xprt_free(xprt);
1332 }
1333
1334 /**
1335  * xs_destroy - prepare to shutdown a transport
1336  * @xprt: doomed transport
1337  *
1338  */
1339 static void xs_destroy(struct rpc_xprt *xprt)
1340 {
1341         struct sock_xprt *transport = container_of(xprt,
1342                         struct sock_xprt, xprt);
1343         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1344
1345         cancel_delayed_work_sync(&transport->connect_worker);
1346         xs_close(xprt);
1347         cancel_work_sync(&transport->recv_worker);
1348         cancel_work_sync(&transport->error_worker);
1349         xs_xprt_free(xprt);
1350         module_put(THIS_MODULE);
1351 }
1352
1353 /**
1354  * xs_udp_data_read_skb - receive callback for UDP sockets
1355  * @xprt: transport
1356  * @sk: socket
1357  * @skb: skbuff
1358  *
1359  */
1360 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1361                 struct sock *sk,
1362                 struct sk_buff *skb)
1363 {
1364         struct rpc_task *task;
1365         struct rpc_rqst *rovr;
1366         int repsize, copied;
1367         u32 _xid;
1368         __be32 *xp;
1369
1370         repsize = skb->len;
1371         if (repsize < 4) {
1372                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1373                 return;
1374         }
1375
1376         /* Copy the XID from the skb... */
1377         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1378         if (xp == NULL)
1379                 return;
1380
1381         /* Look up and lock the request corresponding to the given XID */
1382         spin_lock(&xprt->queue_lock);
1383         rovr = xprt_lookup_rqst(xprt, *xp);
1384         if (!rovr)
1385                 goto out_unlock;
1386         xprt_pin_rqst(rovr);
1387         xprt_update_rtt(rovr->rq_task);
1388         spin_unlock(&xprt->queue_lock);
1389         task = rovr->rq_task;
1390
1391         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1392                 copied = repsize;
1393
1394         /* Suck it into the iovec, verify checksum if not done by hw. */
1395         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1396                 spin_lock(&xprt->queue_lock);
1397                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1398                 goto out_unpin;
1399         }
1400
1401
1402         spin_lock(&xprt->transport_lock);
1403         xprt_adjust_cwnd(xprt, task, copied);
1404         spin_unlock(&xprt->transport_lock);
1405         spin_lock(&xprt->queue_lock);
1406         xprt_complete_rqst(task, copied);
1407         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1408 out_unpin:
1409         xprt_unpin_rqst(rovr);
1410  out_unlock:
1411         spin_unlock(&xprt->queue_lock);
1412 }
1413
1414 static void xs_udp_data_receive(struct sock_xprt *transport)
1415 {
1416         struct sk_buff *skb;
1417         struct sock *sk;
1418         int err;
1419
1420         mutex_lock(&transport->recv_mutex);
1421         sk = transport->inet;
1422         if (sk == NULL)
1423                 goto out;
1424         for (;;) {
1425                 skb = skb_recv_udp(sk, 0, 1, &err);
1426                 if (skb == NULL)
1427                         break;
1428                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1429                 consume_skb(skb);
1430                 cond_resched();
1431         }
1432         xs_poll_check_readable(transport);
1433 out:
1434         mutex_unlock(&transport->recv_mutex);
1435 }
1436
1437 static void xs_udp_data_receive_workfn(struct work_struct *work)
1438 {
1439         struct sock_xprt *transport =
1440                 container_of(work, struct sock_xprt, recv_worker);
1441         unsigned int pflags = memalloc_nofs_save();
1442
1443         xs_udp_data_receive(transport);
1444         memalloc_nofs_restore(pflags);
1445 }
1446
1447 /**
1448  * xs_data_ready - "data ready" callback for UDP sockets
1449  * @sk: socket with data to read
1450  *
1451  */
1452 static void xs_data_ready(struct sock *sk)
1453 {
1454         struct rpc_xprt *xprt;
1455
1456         read_lock_bh(&sk->sk_callback_lock);
1457         dprintk("RPC:       xs_data_ready...\n");
1458         xprt = xprt_from_sock(sk);
1459         if (xprt != NULL) {
1460                 struct sock_xprt *transport = container_of(xprt,
1461                                 struct sock_xprt, xprt);
1462                 transport->old_data_ready(sk);
1463                 /* Any data means we had a useful conversation, so
1464                  * then we don't need to delay the next reconnect
1465                  */
1466                 if (xprt->reestablish_timeout)
1467                         xprt->reestablish_timeout = 0;
1468                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1469                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1470         }
1471         read_unlock_bh(&sk->sk_callback_lock);
1472 }
1473
1474 /*
1475  * Helper function to force a TCP close if the server is sending
1476  * junk and/or it has put us in CLOSE_WAIT
1477  */
1478 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1479 {
1480         xprt_force_disconnect(xprt);
1481 }
1482
1483 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1484 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1485 {
1486         return PAGE_SIZE;
1487 }
1488 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1489
1490 /**
1491  * xs_tcp_state_change - callback to handle TCP socket state changes
1492  * @sk: socket whose state has changed
1493  *
1494  */
1495 static void xs_tcp_state_change(struct sock *sk)
1496 {
1497         struct rpc_xprt *xprt;
1498         struct sock_xprt *transport;
1499
1500         read_lock_bh(&sk->sk_callback_lock);
1501         if (!(xprt = xprt_from_sock(sk)))
1502                 goto out;
1503         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1504         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1505                         sk->sk_state, xprt_connected(xprt),
1506                         sock_flag(sk, SOCK_DEAD),
1507                         sock_flag(sk, SOCK_ZAPPED),
1508                         sk->sk_shutdown);
1509
1510         transport = container_of(xprt, struct sock_xprt, xprt);
1511         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1512         switch (sk->sk_state) {
1513         case TCP_ESTABLISHED:
1514                 if (!xprt_test_and_set_connected(xprt)) {
1515                         xprt->connect_cookie++;
1516                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1517                         xprt_clear_connecting(xprt);
1518
1519                         xprt->stat.connect_count++;
1520                         xprt->stat.connect_time += (long)jiffies -
1521                                                    xprt->stat.connect_start;
1522                         xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1523                 }
1524                 break;
1525         case TCP_FIN_WAIT1:
1526                 /* The client initiated a shutdown of the socket */
1527                 xprt->connect_cookie++;
1528                 xprt->reestablish_timeout = 0;
1529                 set_bit(XPRT_CLOSING, &xprt->state);
1530                 smp_mb__before_atomic();
1531                 clear_bit(XPRT_CONNECTED, &xprt->state);
1532                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1533                 smp_mb__after_atomic();
1534                 break;
1535         case TCP_CLOSE_WAIT:
1536                 /* The server initiated a shutdown of the socket */
1537                 xprt->connect_cookie++;
1538                 clear_bit(XPRT_CONNECTED, &xprt->state);
1539                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1540                 /* fall through */
1541         case TCP_CLOSING:
1542                 /*
1543                  * If the server closed down the connection, make sure that
1544                  * we back off before reconnecting
1545                  */
1546                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1547                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1548                 break;
1549         case TCP_LAST_ACK:
1550                 set_bit(XPRT_CLOSING, &xprt->state);
1551                 smp_mb__before_atomic();
1552                 clear_bit(XPRT_CONNECTED, &xprt->state);
1553                 smp_mb__after_atomic();
1554                 break;
1555         case TCP_CLOSE:
1556                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1557                                         &transport->sock_state))
1558                         xprt_clear_connecting(xprt);
1559                 clear_bit(XPRT_CLOSING, &xprt->state);
1560                 /* Trigger the socket release */
1561                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1562         }
1563  out:
1564         read_unlock_bh(&sk->sk_callback_lock);
1565 }
1566
1567 static void xs_write_space(struct sock *sk)
1568 {
1569         struct socket_wq *wq;
1570         struct sock_xprt *transport;
1571         struct rpc_xprt *xprt;
1572
1573         if (!sk->sk_socket)
1574                 return;
1575         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1576
1577         if (unlikely(!(xprt = xprt_from_sock(sk))))
1578                 return;
1579         transport = container_of(xprt, struct sock_xprt, xprt);
1580         rcu_read_lock();
1581         wq = rcu_dereference(sk->sk_wq);
1582         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1583                 goto out;
1584
1585         xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1586         sk->sk_write_pending--;
1587 out:
1588         rcu_read_unlock();
1589 }
1590
1591 /**
1592  * xs_udp_write_space - callback invoked when socket buffer space
1593  *                             becomes available
1594  * @sk: socket whose state has changed
1595  *
1596  * Called when more output buffer space is available for this socket.
1597  * We try not to wake our writers until they can make "significant"
1598  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1599  * with a bunch of small requests.
1600  */
1601 static void xs_udp_write_space(struct sock *sk)
1602 {
1603         read_lock_bh(&sk->sk_callback_lock);
1604
1605         /* from net/core/sock.c:sock_def_write_space */
1606         if (sock_writeable(sk))
1607                 xs_write_space(sk);
1608
1609         read_unlock_bh(&sk->sk_callback_lock);
1610 }
1611
1612 /**
1613  * xs_tcp_write_space - callback invoked when socket buffer space
1614  *                             becomes available
1615  * @sk: socket whose state has changed
1616  *
1617  * Called when more output buffer space is available for this socket.
1618  * We try not to wake our writers until they can make "significant"
1619  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1620  * with a bunch of small requests.
1621  */
1622 static void xs_tcp_write_space(struct sock *sk)
1623 {
1624         read_lock_bh(&sk->sk_callback_lock);
1625
1626         /* from net/core/stream.c:sk_stream_write_space */
1627         if (sk_stream_is_writeable(sk))
1628                 xs_write_space(sk);
1629
1630         read_unlock_bh(&sk->sk_callback_lock);
1631 }
1632
1633 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1634 {
1635         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1636         struct sock *sk = transport->inet;
1637
1638         if (transport->rcvsize) {
1639                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1640                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1641         }
1642         if (transport->sndsize) {
1643                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1644                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1645                 sk->sk_write_space(sk);
1646         }
1647 }
1648
1649 /**
1650  * xs_udp_set_buffer_size - set send and receive limits
1651  * @xprt: generic transport
1652  * @sndsize: requested size of send buffer, in bytes
1653  * @rcvsize: requested size of receive buffer, in bytes
1654  *
1655  * Set socket send and receive buffer size limits.
1656  */
1657 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1658 {
1659         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1660
1661         transport->sndsize = 0;
1662         if (sndsize)
1663                 transport->sndsize = sndsize + 1024;
1664         transport->rcvsize = 0;
1665         if (rcvsize)
1666                 transport->rcvsize = rcvsize + 1024;
1667
1668         xs_udp_do_set_buffer_size(xprt);
1669 }
1670
1671 /**
1672  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1673  * @xprt: controlling transport
1674  * @task: task that timed out
1675  *
1676  * Adjust the congestion window after a retransmit timeout has occurred.
1677  */
1678 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1679 {
1680         spin_lock(&xprt->transport_lock);
1681         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1682         spin_unlock(&xprt->transport_lock);
1683 }
1684
1685 static int xs_get_random_port(void)
1686 {
1687         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1688         unsigned short range;
1689         unsigned short rand;
1690
1691         if (max < min)
1692                 return -EADDRINUSE;
1693         range = max - min + 1;
1694         rand = (unsigned short) prandom_u32() % range;
1695         return rand + min;
1696 }
1697
1698 /**
1699  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1700  * @sock: socket
1701  *
1702  * Note that this function has to be called on all sockets that share the
1703  * same port, and it must be called before binding.
1704  */
1705 static void xs_sock_set_reuseport(struct socket *sock)
1706 {
1707         int opt = 1;
1708
1709         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1710                         (char *)&opt, sizeof(opt));
1711 }
1712
1713 static unsigned short xs_sock_getport(struct socket *sock)
1714 {
1715         struct sockaddr_storage buf;
1716         unsigned short port = 0;
1717
1718         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1719                 goto out;
1720         switch (buf.ss_family) {
1721         case AF_INET6:
1722                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1723                 break;
1724         case AF_INET:
1725                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1726         }
1727 out:
1728         return port;
1729 }
1730
1731 /**
1732  * xs_set_port - reset the port number in the remote endpoint address
1733  * @xprt: generic transport
1734  * @port: new port number
1735  *
1736  */
1737 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1738 {
1739         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1740
1741         rpc_set_port(xs_addr(xprt), port);
1742         xs_update_peer_port(xprt);
1743 }
1744
1745 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1746 {
1747         if (transport->srcport == 0)
1748                 transport->srcport = xs_sock_getport(sock);
1749 }
1750
1751 static int xs_get_srcport(struct sock_xprt *transport)
1752 {
1753         int port = transport->srcport;
1754
1755         if (port == 0 && transport->xprt.resvport)
1756                 port = xs_get_random_port();
1757         return port;
1758 }
1759
1760 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1761 {
1762         if (transport->srcport != 0)
1763                 transport->srcport = 0;
1764         if (!transport->xprt.resvport)
1765                 return 0;
1766         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1767                 return xprt_max_resvport;
1768         return --port;
1769 }
1770 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1771 {
1772         struct sockaddr_storage myaddr;
1773         int err, nloop = 0;
1774         int port = xs_get_srcport(transport);
1775         unsigned short last;
1776
1777         /*
1778          * If we are asking for any ephemeral port (i.e. port == 0 &&
1779          * transport->xprt.resvport == 0), don't bind.  Let the local
1780          * port selection happen implicitly when the socket is used
1781          * (for example at connect time).
1782          *
1783          * This ensures that we can continue to establish TCP
1784          * connections even when all local ephemeral ports are already
1785          * a part of some TCP connection.  This makes no difference
1786          * for UDP sockets, but also doens't harm them.
1787          *
1788          * If we're asking for any reserved port (i.e. port == 0 &&
1789          * transport->xprt.resvport == 1) xs_get_srcport above will
1790          * ensure that port is non-zero and we will bind as needed.
1791          */
1792         if (port <= 0)
1793                 return port;
1794
1795         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1796         do {
1797                 rpc_set_port((struct sockaddr *)&myaddr, port);
1798                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1799                                 transport->xprt.addrlen);
1800                 if (err == 0) {
1801                         transport->srcport = port;
1802                         break;
1803                 }
1804                 last = port;
1805                 port = xs_next_srcport(transport, port);
1806                 if (port > last)
1807                         nloop++;
1808         } while (err == -EADDRINUSE && nloop != 2);
1809
1810         if (myaddr.ss_family == AF_INET)
1811                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1812                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1813                                 port, err ? "failed" : "ok", err);
1814         else
1815                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1816                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1817                                 port, err ? "failed" : "ok", err);
1818         return err;
1819 }
1820
1821 /*
1822  * We don't support autobind on AF_LOCAL sockets
1823  */
1824 static void xs_local_rpcbind(struct rpc_task *task)
1825 {
1826         xprt_set_bound(task->tk_xprt);
1827 }
1828
1829 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1830 {
1831 }
1832
1833 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1834 static struct lock_class_key xs_key[2];
1835 static struct lock_class_key xs_slock_key[2];
1836
1837 static inline void xs_reclassify_socketu(struct socket *sock)
1838 {
1839         struct sock *sk = sock->sk;
1840
1841         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1842                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1843 }
1844
1845 static inline void xs_reclassify_socket4(struct socket *sock)
1846 {
1847         struct sock *sk = sock->sk;
1848
1849         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1850                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1851 }
1852
1853 static inline void xs_reclassify_socket6(struct socket *sock)
1854 {
1855         struct sock *sk = sock->sk;
1856
1857         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1858                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1859 }
1860
1861 static inline void xs_reclassify_socket(int family, struct socket *sock)
1862 {
1863         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1864                 return;
1865
1866         switch (family) {
1867         case AF_LOCAL:
1868                 xs_reclassify_socketu(sock);
1869                 break;
1870         case AF_INET:
1871                 xs_reclassify_socket4(sock);
1872                 break;
1873         case AF_INET6:
1874                 xs_reclassify_socket6(sock);
1875                 break;
1876         }
1877 }
1878 #else
1879 static inline void xs_reclassify_socket(int family, struct socket *sock)
1880 {
1881 }
1882 #endif
1883
1884 static void xs_dummy_setup_socket(struct work_struct *work)
1885 {
1886 }
1887
1888 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1889                 struct sock_xprt *transport, int family, int type,
1890                 int protocol, bool reuseport)
1891 {
1892         struct file *filp;
1893         struct socket *sock;
1894         int err;
1895
1896         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1897         if (err < 0) {
1898                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1899                                 protocol, -err);
1900                 goto out;
1901         }
1902         xs_reclassify_socket(family, sock);
1903
1904         if (reuseport)
1905                 xs_sock_set_reuseport(sock);
1906
1907         err = xs_bind(transport, sock);
1908         if (err) {
1909                 sock_release(sock);
1910                 goto out;
1911         }
1912
1913         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1914         if (IS_ERR(filp))
1915                 return ERR_CAST(filp);
1916         transport->file = filp;
1917
1918         return sock;
1919 out:
1920         return ERR_PTR(err);
1921 }
1922
1923 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1924                                       struct socket *sock)
1925 {
1926         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1927                                                                         xprt);
1928
1929         if (!transport->inet) {
1930                 struct sock *sk = sock->sk;
1931
1932                 write_lock_bh(&sk->sk_callback_lock);
1933
1934                 xs_save_old_callbacks(transport, sk);
1935
1936                 sk->sk_user_data = xprt;
1937                 sk->sk_data_ready = xs_data_ready;
1938                 sk->sk_write_space = xs_udp_write_space;
1939                 sock_set_flag(sk, SOCK_FASYNC);
1940                 sk->sk_error_report = xs_error_report;
1941
1942                 xprt_clear_connected(xprt);
1943
1944                 /* Reset to new socket */
1945                 transport->sock = sock;
1946                 transport->inet = sk;
1947
1948                 write_unlock_bh(&sk->sk_callback_lock);
1949         }
1950
1951         xs_stream_start_connect(transport);
1952
1953         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1954 }
1955
1956 /**
1957  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1958  * @transport: socket transport to connect
1959  */
1960 static int xs_local_setup_socket(struct sock_xprt *transport)
1961 {
1962         struct rpc_xprt *xprt = &transport->xprt;
1963         struct file *filp;
1964         struct socket *sock;
1965         int status = -EIO;
1966
1967         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1968                                         SOCK_STREAM, 0, &sock, 1);
1969         if (status < 0) {
1970                 dprintk("RPC:       can't create AF_LOCAL "
1971                         "transport socket (%d).\n", -status);
1972                 goto out;
1973         }
1974         xs_reclassify_socket(AF_LOCAL, sock);
1975
1976         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1977         if (IS_ERR(filp)) {
1978                 status = PTR_ERR(filp);
1979                 goto out;
1980         }
1981         transport->file = filp;
1982
1983         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1984                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1985
1986         status = xs_local_finish_connecting(xprt, sock);
1987         trace_rpc_socket_connect(xprt, sock, status);
1988         switch (status) {
1989         case 0:
1990                 dprintk("RPC:       xprt %p connected to %s\n",
1991                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1992                 xprt->stat.connect_count++;
1993                 xprt->stat.connect_time += (long)jiffies -
1994                                            xprt->stat.connect_start;
1995                 xprt_set_connected(xprt);
1996         case -ENOBUFS:
1997                 break;
1998         case -ENOENT:
1999                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
2000                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2001                 break;
2002         case -ECONNREFUSED:
2003                 dprintk("RPC:       xprt %p: connection refused for %s\n",
2004                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
2005                 break;
2006         default:
2007                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
2008                                 __func__, -status,
2009                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
2010         }
2011
2012 out:
2013         xprt_clear_connecting(xprt);
2014         xprt_wake_pending_tasks(xprt, status);
2015         return status;
2016 }
2017
2018 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2019 {
2020         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2021         int ret;
2022
2023          if (RPC_IS_ASYNC(task)) {
2024                 /*
2025                  * We want the AF_LOCAL connect to be resolved in the
2026                  * filesystem namespace of the process making the rpc
2027                  * call.  Thus we connect synchronously.
2028                  *
2029                  * If we want to support asynchronous AF_LOCAL calls,
2030                  * we'll need to figure out how to pass a namespace to
2031                  * connect.
2032                  */
2033                 task->tk_rpc_status = -ENOTCONN;
2034                 rpc_exit(task, -ENOTCONN);
2035                 return;
2036         }
2037         ret = xs_local_setup_socket(transport);
2038         if (ret && !RPC_IS_SOFTCONN(task))
2039                 msleep_interruptible(15000);
2040 }
2041
2042 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2043 /*
2044  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
2045  * know that we have exclusive access to the socket), to guard against
2046  * races with xs_reset_transport.
2047  */
2048 static void xs_set_memalloc(struct rpc_xprt *xprt)
2049 {
2050         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2051                         xprt);
2052
2053         /*
2054          * If there's no sock, then we have nothing to set. The
2055          * reconnecting process will get it for us.
2056          */
2057         if (!transport->inet)
2058                 return;
2059         if (atomic_read(&xprt->swapper))
2060                 sk_set_memalloc(transport->inet);
2061 }
2062
2063 /**
2064  * xs_enable_swap - Tag this transport as being used for swap.
2065  * @xprt: transport to tag
2066  *
2067  * Take a reference to this transport on behalf of the rpc_clnt, and
2068  * optionally mark it for swapping if it wasn't already.
2069  */
2070 static int
2071 xs_enable_swap(struct rpc_xprt *xprt)
2072 {
2073         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2074
2075         if (atomic_inc_return(&xprt->swapper) != 1)
2076                 return 0;
2077         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2078                 return -ERESTARTSYS;
2079         if (xs->inet)
2080                 sk_set_memalloc(xs->inet);
2081         xprt_release_xprt(xprt, NULL);
2082         return 0;
2083 }
2084
2085 /**
2086  * xs_disable_swap - Untag this transport as being used for swap.
2087  * @xprt: transport to tag
2088  *
2089  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2090  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2091  */
2092 static void
2093 xs_disable_swap(struct rpc_xprt *xprt)
2094 {
2095         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2096
2097         if (!atomic_dec_and_test(&xprt->swapper))
2098                 return;
2099         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2100                 return;
2101         if (xs->inet)
2102                 sk_clear_memalloc(xs->inet);
2103         xprt_release_xprt(xprt, NULL);
2104 }
2105 #else
2106 static void xs_set_memalloc(struct rpc_xprt *xprt)
2107 {
2108 }
2109
2110 static int
2111 xs_enable_swap(struct rpc_xprt *xprt)
2112 {
2113         return -EINVAL;
2114 }
2115
2116 static void
2117 xs_disable_swap(struct rpc_xprt *xprt)
2118 {
2119 }
2120 #endif
2121
2122 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2123 {
2124         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2125
2126         if (!transport->inet) {
2127                 struct sock *sk = sock->sk;
2128
2129                 write_lock_bh(&sk->sk_callback_lock);
2130
2131                 xs_save_old_callbacks(transport, sk);
2132
2133                 sk->sk_user_data = xprt;
2134                 sk->sk_data_ready = xs_data_ready;
2135                 sk->sk_write_space = xs_udp_write_space;
2136                 sock_set_flag(sk, SOCK_FASYNC);
2137
2138                 xprt_set_connected(xprt);
2139
2140                 /* Reset to new socket */
2141                 transport->sock = sock;
2142                 transport->inet = sk;
2143
2144                 xs_set_memalloc(xprt);
2145
2146                 write_unlock_bh(&sk->sk_callback_lock);
2147         }
2148         xs_udp_do_set_buffer_size(xprt);
2149
2150         xprt->stat.connect_start = jiffies;
2151 }
2152
2153 static void xs_udp_setup_socket(struct work_struct *work)
2154 {
2155         struct sock_xprt *transport =
2156                 container_of(work, struct sock_xprt, connect_worker.work);
2157         struct rpc_xprt *xprt = &transport->xprt;
2158         struct socket *sock;
2159         int status = -EIO;
2160
2161         sock = xs_create_sock(xprt, transport,
2162                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2163                         IPPROTO_UDP, false);
2164         if (IS_ERR(sock))
2165                 goto out;
2166
2167         dprintk("RPC:       worker connecting xprt %p via %s to "
2168                                 "%s (port %s)\n", xprt,
2169                         xprt->address_strings[RPC_DISPLAY_PROTO],
2170                         xprt->address_strings[RPC_DISPLAY_ADDR],
2171                         xprt->address_strings[RPC_DISPLAY_PORT]);
2172
2173         xs_udp_finish_connecting(xprt, sock);
2174         trace_rpc_socket_connect(xprt, sock, 0);
2175         status = 0;
2176 out:
2177         xprt_clear_connecting(xprt);
2178         xprt_unlock_connect(xprt, transport);
2179         xprt_wake_pending_tasks(xprt, status);
2180 }
2181
2182 /**
2183  * xs_tcp_shutdown - gracefully shut down a TCP socket
2184  * @xprt: transport
2185  *
2186  * Initiates a graceful shutdown of the TCP socket by calling the
2187  * equivalent of shutdown(SHUT_RDWR);
2188  */
2189 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2190 {
2191         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2192         struct socket *sock = transport->sock;
2193         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2194
2195         if (sock == NULL)
2196                 return;
2197         switch (skst) {
2198         default:
2199                 kernel_sock_shutdown(sock, SHUT_RDWR);
2200                 trace_rpc_socket_shutdown(xprt, sock);
2201                 break;
2202         case TCP_CLOSE:
2203         case TCP_TIME_WAIT:
2204                 xs_reset_transport(transport);
2205         }
2206 }
2207
2208 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2209                 struct socket *sock)
2210 {
2211         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2212         unsigned int keepidle;
2213         unsigned int keepcnt;
2214         unsigned int opt_on = 1;
2215         unsigned int timeo;
2216
2217         spin_lock(&xprt->transport_lock);
2218         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2219         keepcnt = xprt->timeout->to_retries + 1;
2220         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2221                 (xprt->timeout->to_retries + 1);
2222         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2223         spin_unlock(&xprt->transport_lock);
2224
2225         /* TCP Keepalive options */
2226         kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2227                         (char *)&opt_on, sizeof(opt_on));
2228         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2229                         (char *)&keepidle, sizeof(keepidle));
2230         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2231                         (char *)&keepidle, sizeof(keepidle));
2232         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2233                         (char *)&keepcnt, sizeof(keepcnt));
2234
2235         /* TCP user timeout (see RFC5482) */
2236         kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2237                         (char *)&timeo, sizeof(timeo));
2238 }
2239
2240 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2241                 unsigned long connect_timeout,
2242                 unsigned long reconnect_timeout)
2243 {
2244         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2245         struct rpc_timeout to;
2246         unsigned long initval;
2247
2248         spin_lock(&xprt->transport_lock);
2249         if (reconnect_timeout < xprt->max_reconnect_timeout)
2250                 xprt->max_reconnect_timeout = reconnect_timeout;
2251         if (connect_timeout < xprt->connect_timeout) {
2252                 memcpy(&to, xprt->timeout, sizeof(to));
2253                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2254                 /* Arbitrary lower limit */
2255                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2256                         initval = XS_TCP_INIT_REEST_TO << 1;
2257                 to.to_initval = initval;
2258                 to.to_maxval = initval;
2259                 memcpy(&transport->tcp_timeout, &to,
2260                                 sizeof(transport->tcp_timeout));
2261                 xprt->timeout = &transport->tcp_timeout;
2262                 xprt->connect_timeout = connect_timeout;
2263         }
2264         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2265         spin_unlock(&xprt->transport_lock);
2266 }
2267
2268 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2269 {
2270         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2271         int ret = -ENOTCONN;
2272
2273         if (!transport->inet) {
2274                 struct sock *sk = sock->sk;
2275                 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2276
2277                 /* Avoid temporary address, they are bad for long-lived
2278                  * connections such as NFS mounts.
2279                  * RFC4941, section 3.6 suggests that:
2280                  *    Individual applications, which have specific
2281                  *    knowledge about the normal duration of connections,
2282                  *    MAY override this as appropriate.
2283                  */
2284                 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2285                                 (char *)&addr_pref, sizeof(addr_pref));
2286
2287                 xs_tcp_set_socket_timeouts(xprt, sock);
2288
2289                 write_lock_bh(&sk->sk_callback_lock);
2290
2291                 xs_save_old_callbacks(transport, sk);
2292
2293                 sk->sk_user_data = xprt;
2294                 sk->sk_data_ready = xs_data_ready;
2295                 sk->sk_state_change = xs_tcp_state_change;
2296                 sk->sk_write_space = xs_tcp_write_space;
2297                 sock_set_flag(sk, SOCK_FASYNC);
2298                 sk->sk_error_report = xs_error_report;
2299
2300                 /* socket options */
2301                 sock_reset_flag(sk, SOCK_LINGER);
2302                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2303
2304                 xprt_clear_connected(xprt);
2305
2306                 /* Reset to new socket */
2307                 transport->sock = sock;
2308                 transport->inet = sk;
2309
2310                 write_unlock_bh(&sk->sk_callback_lock);
2311         }
2312
2313         if (!xprt_bound(xprt))
2314                 goto out;
2315
2316         xs_set_memalloc(xprt);
2317
2318         xs_stream_start_connect(transport);
2319
2320         /* Tell the socket layer to start connecting... */
2321         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2322         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2323         switch (ret) {
2324         case 0:
2325                 xs_set_srcport(transport, sock);
2326                 /* fall through */
2327         case -EINPROGRESS:
2328                 /* SYN_SENT! */
2329                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2330                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2331                 break;
2332         case -EADDRNOTAVAIL:
2333                 /* Source port number is unavailable. Try a new one! */
2334                 transport->srcport = 0;
2335         }
2336 out:
2337         return ret;
2338 }
2339
2340 /**
2341  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2342  * @work: queued work item
2343  *
2344  * Invoked by a work queue tasklet.
2345  */
2346 static void xs_tcp_setup_socket(struct work_struct *work)
2347 {
2348         struct sock_xprt *transport =
2349                 container_of(work, struct sock_xprt, connect_worker.work);
2350         struct socket *sock = transport->sock;
2351         struct rpc_xprt *xprt = &transport->xprt;
2352         int status = -EIO;
2353
2354         if (!sock) {
2355                 sock = xs_create_sock(xprt, transport,
2356                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2357                                 IPPROTO_TCP, true);
2358                 if (IS_ERR(sock)) {
2359                         status = PTR_ERR(sock);
2360                         goto out;
2361                 }
2362         }
2363
2364         dprintk("RPC:       worker connecting xprt %p via %s to "
2365                                 "%s (port %s)\n", xprt,
2366                         xprt->address_strings[RPC_DISPLAY_PROTO],
2367                         xprt->address_strings[RPC_DISPLAY_ADDR],
2368                         xprt->address_strings[RPC_DISPLAY_PORT]);
2369
2370         status = xs_tcp_finish_connecting(xprt, sock);
2371         trace_rpc_socket_connect(xprt, sock, status);
2372         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2373                         xprt, -status, xprt_connected(xprt),
2374                         sock->sk->sk_state);
2375         switch (status) {
2376         default:
2377                 printk("%s: connect returned unhandled error %d\n",
2378                         __func__, status);
2379                 /* fall through */
2380         case -EADDRNOTAVAIL:
2381                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2382                  * and retry
2383                  */
2384                 xs_tcp_force_close(xprt);
2385                 break;
2386         case 0:
2387         case -EINPROGRESS:
2388         case -EALREADY:
2389                 xprt_unlock_connect(xprt, transport);
2390                 return;
2391         case -EINVAL:
2392                 /* Happens, for instance, if the user specified a link
2393                  * local IPv6 address without a scope-id.
2394                  */
2395         case -ECONNREFUSED:
2396         case -ECONNRESET:
2397         case -ENETDOWN:
2398         case -ENETUNREACH:
2399         case -EHOSTUNREACH:
2400         case -EADDRINUSE:
2401         case -ENOBUFS:
2402                 /*
2403                  * xs_tcp_force_close() wakes tasks with -EIO.
2404                  * We need to wake them first to ensure the
2405                  * correct error code.
2406                  */
2407                 xprt_wake_pending_tasks(xprt, status);
2408                 xs_tcp_force_close(xprt);
2409                 goto out;
2410         }
2411         status = -EAGAIN;
2412 out:
2413         xprt_clear_connecting(xprt);
2414         xprt_unlock_connect(xprt, transport);
2415         xprt_wake_pending_tasks(xprt, status);
2416 }
2417
2418 /**
2419  * xs_connect - connect a socket to a remote endpoint
2420  * @xprt: pointer to transport structure
2421  * @task: address of RPC task that manages state of connect request
2422  *
2423  * TCP: If the remote end dropped the connection, delay reconnecting.
2424  *
2425  * UDP socket connects are synchronous, but we use a work queue anyway
2426  * to guarantee that even unprivileged user processes can set up a
2427  * socket on a privileged port.
2428  *
2429  * If a UDP socket connect fails, the delay behavior here prevents
2430  * retry floods (hard mounts).
2431  */
2432 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2433 {
2434         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2435         unsigned long delay = 0;
2436
2437         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2438
2439         if (transport->sock != NULL) {
2440                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2441                                 "seconds\n",
2442                                 xprt, xprt->reestablish_timeout / HZ);
2443
2444                 /* Start by resetting any existing state */
2445                 xs_reset_transport(transport);
2446
2447                 delay = xprt_reconnect_delay(xprt);
2448                 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2449
2450         } else
2451                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2452
2453         queue_delayed_work(xprtiod_workqueue,
2454                         &transport->connect_worker,
2455                         delay);
2456 }
2457
2458 static void xs_wake_disconnect(struct sock_xprt *transport)
2459 {
2460         if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2461                 xs_tcp_force_close(&transport->xprt);
2462 }
2463
2464 static void xs_wake_write(struct sock_xprt *transport)
2465 {
2466         if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2467                 xprt_write_space(&transport->xprt);
2468 }
2469
2470 static void xs_wake_error(struct sock_xprt *transport)
2471 {
2472         int sockerr;
2473         int sockerr_len = sizeof(sockerr);
2474
2475         if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2476                 return;
2477         mutex_lock(&transport->recv_mutex);
2478         if (transport->sock == NULL)
2479                 goto out;
2480         if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2481                 goto out;
2482         if (kernel_getsockopt(transport->sock, SOL_SOCKET, SO_ERROR,
2483                                 (char *)&sockerr, &sockerr_len) != 0)
2484                 goto out;
2485         if (sockerr < 0)
2486                 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2487 out:
2488         mutex_unlock(&transport->recv_mutex);
2489 }
2490
2491 static void xs_wake_pending(struct sock_xprt *transport)
2492 {
2493         if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2494                 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2495 }
2496
2497 static void xs_error_handle(struct work_struct *work)
2498 {
2499         struct sock_xprt *transport = container_of(work,
2500                         struct sock_xprt, error_worker);
2501
2502         xs_wake_disconnect(transport);
2503         xs_wake_write(transport);
2504         xs_wake_error(transport);
2505         xs_wake_pending(transport);
2506 }
2507
2508 /**
2509  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2510  * @xprt: rpc_xprt struct containing statistics
2511  * @seq: output file
2512  *
2513  */
2514 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2515 {
2516         long idle_time = 0;
2517
2518         if (xprt_connected(xprt))
2519                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2520
2521         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2522                         "%llu %llu %lu %llu %llu\n",
2523                         xprt->stat.bind_count,
2524                         xprt->stat.connect_count,
2525                         xprt->stat.connect_time / HZ,
2526                         idle_time,
2527                         xprt->stat.sends,
2528                         xprt->stat.recvs,
2529                         xprt->stat.bad_xids,
2530                         xprt->stat.req_u,
2531                         xprt->stat.bklog_u,
2532                         xprt->stat.max_slots,
2533                         xprt->stat.sending_u,
2534                         xprt->stat.pending_u);
2535 }
2536
2537 /**
2538  * xs_udp_print_stats - display UDP socket-specifc stats
2539  * @xprt: rpc_xprt struct containing statistics
2540  * @seq: output file
2541  *
2542  */
2543 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2544 {
2545         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2546
2547         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2548                         "%lu %llu %llu\n",
2549                         transport->srcport,
2550                         xprt->stat.bind_count,
2551                         xprt->stat.sends,
2552                         xprt->stat.recvs,
2553                         xprt->stat.bad_xids,
2554                         xprt->stat.req_u,
2555                         xprt->stat.bklog_u,
2556                         xprt->stat.max_slots,
2557                         xprt->stat.sending_u,
2558                         xprt->stat.pending_u);
2559 }
2560
2561 /**
2562  * xs_tcp_print_stats - display TCP socket-specifc stats
2563  * @xprt: rpc_xprt struct containing statistics
2564  * @seq: output file
2565  *
2566  */
2567 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2568 {
2569         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2570         long idle_time = 0;
2571
2572         if (xprt_connected(xprt))
2573                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2574
2575         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2576                         "%llu %llu %lu %llu %llu\n",
2577                         transport->srcport,
2578                         xprt->stat.bind_count,
2579                         xprt->stat.connect_count,
2580                         xprt->stat.connect_time / HZ,
2581                         idle_time,
2582                         xprt->stat.sends,
2583                         xprt->stat.recvs,
2584                         xprt->stat.bad_xids,
2585                         xprt->stat.req_u,
2586                         xprt->stat.bklog_u,
2587                         xprt->stat.max_slots,
2588                         xprt->stat.sending_u,
2589                         xprt->stat.pending_u);
2590 }
2591
2592 /*
2593  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2594  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2595  * to use the server side send routines.
2596  */
2597 static int bc_malloc(struct rpc_task *task)
2598 {
2599         struct rpc_rqst *rqst = task->tk_rqstp;
2600         size_t size = rqst->rq_callsize;
2601         struct page *page;
2602         struct rpc_buffer *buf;
2603
2604         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2605                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2606                           size);
2607                 return -EINVAL;
2608         }
2609
2610         page = alloc_page(GFP_KERNEL);
2611         if (!page)
2612                 return -ENOMEM;
2613
2614         buf = page_address(page);
2615         buf->len = PAGE_SIZE;
2616
2617         rqst->rq_buffer = buf->data;
2618         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2619         return 0;
2620 }
2621
2622 /*
2623  * Free the space allocated in the bc_alloc routine
2624  */
2625 static void bc_free(struct rpc_task *task)
2626 {
2627         void *buffer = task->tk_rqstp->rq_buffer;
2628         struct rpc_buffer *buf;
2629
2630         buf = container_of(buffer, struct rpc_buffer, data);
2631         free_page((unsigned long)buf);
2632 }
2633
2634 /*
2635  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2636  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2637  */
2638 static int bc_sendto(struct rpc_rqst *req)
2639 {
2640         int len;
2641         struct xdr_buf *xbufp = &req->rq_snd_buf;
2642         struct sock_xprt *transport =
2643                         container_of(req->rq_xprt, struct sock_xprt, xprt);
2644         unsigned long headoff;
2645         unsigned long tailoff;
2646         struct page *tailpage;
2647         struct msghdr msg = {
2648                 .msg_flags      = MSG_MORE
2649         };
2650         rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2651                                          (u32)xbufp->len);
2652         struct kvec iov = {
2653                 .iov_base       = &marker,
2654                 .iov_len        = sizeof(marker),
2655         };
2656
2657         len = kernel_sendmsg(transport->sock, &msg, &iov, 1, iov.iov_len);
2658         if (len != iov.iov_len)
2659                 return -EAGAIN;
2660
2661         tailpage = NULL;
2662         if (xbufp->tail[0].iov_len)
2663                 tailpage = virt_to_page(xbufp->tail[0].iov_base);
2664         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2665         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2666         len = svc_send_common(transport->sock, xbufp,
2667                               virt_to_page(xbufp->head[0].iov_base), headoff,
2668                               tailpage, tailoff);
2669         if (len != xbufp->len)
2670                 return -EAGAIN;
2671         return len;
2672 }
2673
2674 /*
2675  * The send routine. Borrows from svc_send
2676  */
2677 static int bc_send_request(struct rpc_rqst *req)
2678 {
2679         struct svc_xprt *xprt;
2680         int len;
2681
2682         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2683         /*
2684          * Get the server socket associated with this callback xprt
2685          */
2686         xprt = req->rq_xprt->bc_xprt;
2687
2688         /*
2689          * Grab the mutex to serialize data as the connection is shared
2690          * with the fore channel
2691          */
2692         mutex_lock(&xprt->xpt_mutex);
2693         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2694                 len = -ENOTCONN;
2695         else
2696                 len = bc_sendto(req);
2697         mutex_unlock(&xprt->xpt_mutex);
2698
2699         if (len > 0)
2700                 len = 0;
2701
2702         return len;
2703 }
2704
2705 /*
2706  * The close routine. Since this is client initiated, we do nothing
2707  */
2708
2709 static void bc_close(struct rpc_xprt *xprt)
2710 {
2711 }
2712
2713 /*
2714  * The xprt destroy routine. Again, because this connection is client
2715  * initiated, we do nothing
2716  */
2717
2718 static void bc_destroy(struct rpc_xprt *xprt)
2719 {
2720         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2721
2722         xs_xprt_free(xprt);
2723         module_put(THIS_MODULE);
2724 }
2725
2726 static const struct rpc_xprt_ops xs_local_ops = {
2727         .reserve_xprt           = xprt_reserve_xprt,
2728         .release_xprt           = xprt_release_xprt,
2729         .alloc_slot             = xprt_alloc_slot,
2730         .free_slot              = xprt_free_slot,
2731         .rpcbind                = xs_local_rpcbind,
2732         .set_port               = xs_local_set_port,
2733         .connect                = xs_local_connect,
2734         .buf_alloc              = rpc_malloc,
2735         .buf_free               = rpc_free,
2736         .prepare_request        = xs_stream_prepare_request,
2737         .send_request           = xs_local_send_request,
2738         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2739         .close                  = xs_close,
2740         .destroy                = xs_destroy,
2741         .print_stats            = xs_local_print_stats,
2742         .enable_swap            = xs_enable_swap,
2743         .disable_swap           = xs_disable_swap,
2744 };
2745
2746 static const struct rpc_xprt_ops xs_udp_ops = {
2747         .set_buffer_size        = xs_udp_set_buffer_size,
2748         .reserve_xprt           = xprt_reserve_xprt_cong,
2749         .release_xprt           = xprt_release_xprt_cong,
2750         .alloc_slot             = xprt_alloc_slot,
2751         .free_slot              = xprt_free_slot,
2752         .rpcbind                = rpcb_getport_async,
2753         .set_port               = xs_set_port,
2754         .connect                = xs_connect,
2755         .buf_alloc              = rpc_malloc,
2756         .buf_free               = rpc_free,
2757         .send_request           = xs_udp_send_request,
2758         .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2759         .timer                  = xs_udp_timer,
2760         .release_request        = xprt_release_rqst_cong,
2761         .close                  = xs_close,
2762         .destroy                = xs_destroy,
2763         .print_stats            = xs_udp_print_stats,
2764         .enable_swap            = xs_enable_swap,
2765         .disable_swap           = xs_disable_swap,
2766         .inject_disconnect      = xs_inject_disconnect,
2767 };
2768
2769 static const struct rpc_xprt_ops xs_tcp_ops = {
2770         .reserve_xprt           = xprt_reserve_xprt,
2771         .release_xprt           = xprt_release_xprt,
2772         .alloc_slot             = xprt_alloc_slot,
2773         .free_slot              = xprt_free_slot,
2774         .rpcbind                = rpcb_getport_async,
2775         .set_port               = xs_set_port,
2776         .connect                = xs_connect,
2777         .buf_alloc              = rpc_malloc,
2778         .buf_free               = rpc_free,
2779         .prepare_request        = xs_stream_prepare_request,
2780         .send_request           = xs_tcp_send_request,
2781         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2782         .close                  = xs_tcp_shutdown,
2783         .destroy                = xs_destroy,
2784         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2785         .print_stats            = xs_tcp_print_stats,
2786         .enable_swap            = xs_enable_swap,
2787         .disable_swap           = xs_disable_swap,
2788         .inject_disconnect      = xs_inject_disconnect,
2789 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2790         .bc_setup               = xprt_setup_bc,
2791         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2792         .bc_num_slots           = xprt_bc_max_slots,
2793         .bc_free_rqst           = xprt_free_bc_rqst,
2794         .bc_destroy             = xprt_destroy_bc,
2795 #endif
2796 };
2797
2798 /*
2799  * The rpc_xprt_ops for the server backchannel
2800  */
2801
2802 static const struct rpc_xprt_ops bc_tcp_ops = {
2803         .reserve_xprt           = xprt_reserve_xprt,
2804         .release_xprt           = xprt_release_xprt,
2805         .alloc_slot             = xprt_alloc_slot,
2806         .free_slot              = xprt_free_slot,
2807         .buf_alloc              = bc_malloc,
2808         .buf_free               = bc_free,
2809         .send_request           = bc_send_request,
2810         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2811         .close                  = bc_close,
2812         .destroy                = bc_destroy,
2813         .print_stats            = xs_tcp_print_stats,
2814         .enable_swap            = xs_enable_swap,
2815         .disable_swap           = xs_disable_swap,
2816         .inject_disconnect      = xs_inject_disconnect,
2817 };
2818
2819 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2820 {
2821         static const struct sockaddr_in sin = {
2822                 .sin_family             = AF_INET,
2823                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2824         };
2825         static const struct sockaddr_in6 sin6 = {
2826                 .sin6_family            = AF_INET6,
2827                 .sin6_addr              = IN6ADDR_ANY_INIT,
2828         };
2829
2830         switch (family) {
2831         case AF_LOCAL:
2832                 break;
2833         case AF_INET:
2834                 memcpy(sap, &sin, sizeof(sin));
2835                 break;
2836         case AF_INET6:
2837                 memcpy(sap, &sin6, sizeof(sin6));
2838                 break;
2839         default:
2840                 dprintk("RPC:       %s: Bad address family\n", __func__);
2841                 return -EAFNOSUPPORT;
2842         }
2843         return 0;
2844 }
2845
2846 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2847                                       unsigned int slot_table_size,
2848                                       unsigned int max_slot_table_size)
2849 {
2850         struct rpc_xprt *xprt;
2851         struct sock_xprt *new;
2852
2853         if (args->addrlen > sizeof(xprt->addr)) {
2854                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2855                 return ERR_PTR(-EBADF);
2856         }
2857
2858         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2859                         max_slot_table_size);
2860         if (xprt == NULL) {
2861                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2862                                 "rpc_xprt\n");
2863                 return ERR_PTR(-ENOMEM);
2864         }
2865
2866         new = container_of(xprt, struct sock_xprt, xprt);
2867         mutex_init(&new->recv_mutex);
2868         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2869         xprt->addrlen = args->addrlen;
2870         if (args->srcaddr)
2871                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2872         else {
2873                 int err;
2874                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2875                                         (struct sockaddr *)&new->srcaddr);
2876                 if (err != 0) {
2877                         xprt_free(xprt);
2878                         return ERR_PTR(err);
2879                 }
2880         }
2881
2882         return xprt;
2883 }
2884
2885 static const struct rpc_timeout xs_local_default_timeout = {
2886         .to_initval = 10 * HZ,
2887         .to_maxval = 10 * HZ,
2888         .to_retries = 2,
2889 };
2890
2891 /**
2892  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2893  * @args: rpc transport creation arguments
2894  *
2895  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2896  */
2897 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2898 {
2899         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2900         struct sock_xprt *transport;
2901         struct rpc_xprt *xprt;
2902         struct rpc_xprt *ret;
2903
2904         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2905                         xprt_max_tcp_slot_table_entries);
2906         if (IS_ERR(xprt))
2907                 return xprt;
2908         transport = container_of(xprt, struct sock_xprt, xprt);
2909
2910         xprt->prot = 0;
2911         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2912
2913         xprt->bind_timeout = XS_BIND_TO;
2914         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2915         xprt->idle_timeout = XS_IDLE_DISC_TO;
2916
2917         xprt->ops = &xs_local_ops;
2918         xprt->timeout = &xs_local_default_timeout;
2919
2920         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2921         INIT_WORK(&transport->error_worker, xs_error_handle);
2922         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2923
2924         switch (sun->sun_family) {
2925         case AF_LOCAL:
2926                 if (sun->sun_path[0] != '/') {
2927                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2928                                         sun->sun_path);
2929                         ret = ERR_PTR(-EINVAL);
2930                         goto out_err;
2931                 }
2932                 xprt_set_bound(xprt);
2933                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2934                 ret = ERR_PTR(xs_local_setup_socket(transport));
2935                 if (ret)
2936                         goto out_err;
2937                 break;
2938         default:
2939                 ret = ERR_PTR(-EAFNOSUPPORT);
2940                 goto out_err;
2941         }
2942
2943         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2944                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2945
2946         if (try_module_get(THIS_MODULE))
2947                 return xprt;
2948         ret = ERR_PTR(-EINVAL);
2949 out_err:
2950         xs_xprt_free(xprt);
2951         return ret;
2952 }
2953
2954 static const struct rpc_timeout xs_udp_default_timeout = {
2955         .to_initval = 5 * HZ,
2956         .to_maxval = 30 * HZ,
2957         .to_increment = 5 * HZ,
2958         .to_retries = 5,
2959 };
2960
2961 /**
2962  * xs_setup_udp - Set up transport to use a UDP socket
2963  * @args: rpc transport creation arguments
2964  *
2965  */
2966 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2967 {
2968         struct sockaddr *addr = args->dstaddr;
2969         struct rpc_xprt *xprt;
2970         struct sock_xprt *transport;
2971         struct rpc_xprt *ret;
2972
2973         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2974                         xprt_udp_slot_table_entries);
2975         if (IS_ERR(xprt))
2976                 return xprt;
2977         transport = container_of(xprt, struct sock_xprt, xprt);
2978
2979         xprt->prot = IPPROTO_UDP;
2980         /* XXX: header size can vary due to auth type, IPv6, etc. */
2981         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2982
2983         xprt->bind_timeout = XS_BIND_TO;
2984         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2985         xprt->idle_timeout = XS_IDLE_DISC_TO;
2986
2987         xprt->ops = &xs_udp_ops;
2988
2989         xprt->timeout = &xs_udp_default_timeout;
2990
2991         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2992         INIT_WORK(&transport->error_worker, xs_error_handle);
2993         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2994
2995         switch (addr->sa_family) {
2996         case AF_INET:
2997                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2998                         xprt_set_bound(xprt);
2999
3000                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
3001                 break;
3002         case AF_INET6:
3003                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3004                         xprt_set_bound(xprt);
3005
3006                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
3007                 break;
3008         default:
3009                 ret = ERR_PTR(-EAFNOSUPPORT);
3010                 goto out_err;
3011         }
3012
3013         if (xprt_bound(xprt))
3014                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3015                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3016                                 xprt->address_strings[RPC_DISPLAY_PORT],
3017                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3018         else
3019                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3020                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3021                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3022
3023         if (try_module_get(THIS_MODULE))
3024                 return xprt;
3025         ret = ERR_PTR(-EINVAL);
3026 out_err:
3027         xs_xprt_free(xprt);
3028         return ret;
3029 }
3030
3031 static const struct rpc_timeout xs_tcp_default_timeout = {
3032         .to_initval = 60 * HZ,
3033         .to_maxval = 60 * HZ,
3034         .to_retries = 2,
3035 };
3036
3037 /**
3038  * xs_setup_tcp - Set up transport to use a TCP socket
3039  * @args: rpc transport creation arguments
3040  *
3041  */
3042 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
3043 {
3044         struct sockaddr *addr = args->dstaddr;
3045         struct rpc_xprt *xprt;
3046         struct sock_xprt *transport;
3047         struct rpc_xprt *ret;
3048         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
3049
3050         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
3051                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
3052
3053         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3054                         max_slot_table_size);
3055         if (IS_ERR(xprt))
3056                 return xprt;
3057         transport = container_of(xprt, struct sock_xprt, xprt);
3058
3059         xprt->prot = IPPROTO_TCP;
3060         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3061
3062         xprt->bind_timeout = XS_BIND_TO;
3063         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
3064         xprt->idle_timeout = XS_IDLE_DISC_TO;
3065
3066         xprt->ops = &xs_tcp_ops;
3067         xprt->timeout = &xs_tcp_default_timeout;
3068
3069         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
3070         xprt->connect_timeout = xprt->timeout->to_initval *
3071                 (xprt->timeout->to_retries + 1);
3072
3073         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
3074         INIT_WORK(&transport->error_worker, xs_error_handle);
3075         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
3076
3077         switch (addr->sa_family) {
3078         case AF_INET:
3079                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
3080                         xprt_set_bound(xprt);
3081
3082                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
3083                 break;
3084         case AF_INET6:
3085                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
3086                         xprt_set_bound(xprt);
3087
3088                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
3089                 break;
3090         default:
3091                 ret = ERR_PTR(-EAFNOSUPPORT);
3092                 goto out_err;
3093         }
3094
3095         if (xprt_bound(xprt))
3096                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3097                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3098                                 xprt->address_strings[RPC_DISPLAY_PORT],
3099                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3100         else
3101                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
3102                                 xprt->address_strings[RPC_DISPLAY_ADDR],
3103                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
3104
3105         if (try_module_get(THIS_MODULE))
3106                 return xprt;
3107         ret = ERR_PTR(-EINVAL);
3108 out_err:
3109         xs_xprt_free(xprt);
3110         return ret;
3111 }
3112
3113 /**
3114  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3115  * @args: rpc transport creation arguments
3116  *
3117  */
3118 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3119 {
3120         struct sockaddr *addr = args->dstaddr;
3121         struct rpc_xprt *xprt;
3122         struct sock_xprt *transport;
3123         struct svc_sock *bc_sock;
3124         struct rpc_xprt *ret;
3125
3126         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3127                         xprt_tcp_slot_table_entries);
3128         if (IS_ERR(xprt))
3129                 return xprt;
3130         transport = container_of(xprt, struct sock_xprt, xprt);
3131
3132         xprt->prot = IPPROTO_TCP;
3133         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3134         xprt->timeout = &xs_tcp_default_timeout;
3135
3136         /* backchannel */
3137         xprt_set_bound(xprt);
3138         xprt->bind_timeout = 0;
3139         xprt->reestablish_timeout = 0;
3140         xprt->idle_timeout = 0;
3141
3142         xprt->ops = &bc_tcp_ops;
3143
3144         switch (addr->sa_family) {
3145         case AF_INET:
3146                 xs_format_peer_addresses(xprt, "tcp",
3147                                          RPCBIND_NETID_TCP);
3148                 break;
3149         case AF_INET6:
3150                 xs_format_peer_addresses(xprt, "tcp",
3151                                    RPCBIND_NETID_TCP6);
3152                 break;
3153         default:
3154                 ret = ERR_PTR(-EAFNOSUPPORT);
3155                 goto out_err;
3156         }
3157
3158         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3159                         xprt->address_strings[RPC_DISPLAY_ADDR],
3160                         xprt->address_strings[RPC_DISPLAY_PORT],
3161                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3162
3163         /*
3164          * Once we've associated a backchannel xprt with a connection,
3165          * we want to keep it around as long as the connection lasts,
3166          * in case we need to start using it for a backchannel again;
3167          * this reference won't be dropped until bc_xprt is destroyed.
3168          */
3169         xprt_get(xprt);
3170         args->bc_xprt->xpt_bc_xprt = xprt;
3171         xprt->bc_xprt = args->bc_xprt;
3172         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3173         transport->sock = bc_sock->sk_sock;
3174         transport->inet = bc_sock->sk_sk;
3175
3176         /*
3177          * Since we don't want connections for the backchannel, we set
3178          * the xprt status to connected
3179          */
3180         xprt_set_connected(xprt);
3181
3182         if (try_module_get(THIS_MODULE))
3183                 return xprt;
3184
3185         args->bc_xprt->xpt_bc_xprt = NULL;
3186         args->bc_xprt->xpt_bc_xps = NULL;
3187         xprt_put(xprt);
3188         ret = ERR_PTR(-EINVAL);
3189 out_err:
3190         xs_xprt_free(xprt);
3191         return ret;
3192 }
3193
3194 static struct xprt_class        xs_local_transport = {
3195         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3196         .name           = "named UNIX socket",
3197         .owner          = THIS_MODULE,
3198         .ident          = XPRT_TRANSPORT_LOCAL,
3199         .setup          = xs_setup_local,
3200 };
3201
3202 static struct xprt_class        xs_udp_transport = {
3203         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3204         .name           = "udp",
3205         .owner          = THIS_MODULE,
3206         .ident          = XPRT_TRANSPORT_UDP,
3207         .setup          = xs_setup_udp,
3208 };
3209
3210 static struct xprt_class        xs_tcp_transport = {
3211         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3212         .name           = "tcp",
3213         .owner          = THIS_MODULE,
3214         .ident          = XPRT_TRANSPORT_TCP,
3215         .setup          = xs_setup_tcp,
3216 };
3217
3218 static struct xprt_class        xs_bc_tcp_transport = {
3219         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3220         .name           = "tcp NFSv4.1 backchannel",
3221         .owner          = THIS_MODULE,
3222         .ident          = XPRT_TRANSPORT_BC_TCP,
3223         .setup          = xs_setup_bc_tcp,
3224 };
3225
3226 /**
3227  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3228  *
3229  */
3230 int init_socket_xprt(void)
3231 {
3232         if (!sunrpc_table_header)
3233                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3234
3235         xprt_register_transport(&xs_local_transport);
3236         xprt_register_transport(&xs_udp_transport);
3237         xprt_register_transport(&xs_tcp_transport);
3238         xprt_register_transport(&xs_bc_tcp_transport);
3239
3240         return 0;
3241 }
3242
3243 /**
3244  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3245  *
3246  */
3247 void cleanup_socket_xprt(void)
3248 {
3249         if (sunrpc_table_header) {
3250                 unregister_sysctl_table(sunrpc_table_header);
3251                 sunrpc_table_header = NULL;
3252         }
3253
3254         xprt_unregister_transport(&xs_local_transport);
3255         xprt_unregister_transport(&xs_udp_transport);
3256         xprt_unregister_transport(&xs_tcp_transport);
3257         xprt_unregister_transport(&xs_bc_tcp_transport);
3258 }
3259
3260 static int param_set_uint_minmax(const char *val,
3261                 const struct kernel_param *kp,
3262                 unsigned int min, unsigned int max)
3263 {
3264         unsigned int num;
3265         int ret;
3266
3267         if (!val)
3268                 return -EINVAL;
3269         ret = kstrtouint(val, 0, &num);
3270         if (ret)
3271                 return ret;
3272         if (num < min || num > max)
3273                 return -EINVAL;
3274         *((unsigned int *)kp->arg) = num;
3275         return 0;
3276 }
3277
3278 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3279 {
3280         return param_set_uint_minmax(val, kp,
3281                         RPC_MIN_RESVPORT,
3282                         RPC_MAX_RESVPORT);
3283 }
3284
3285 static const struct kernel_param_ops param_ops_portnr = {
3286         .set = param_set_portnr,
3287         .get = param_get_uint,
3288 };
3289
3290 #define param_check_portnr(name, p) \
3291         __param_check(name, p, unsigned int);
3292
3293 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3294 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3295
3296 static int param_set_slot_table_size(const char *val,
3297                                      const struct kernel_param *kp)
3298 {
3299         return param_set_uint_minmax(val, kp,
3300                         RPC_MIN_SLOT_TABLE,
3301                         RPC_MAX_SLOT_TABLE);
3302 }
3303
3304 static const struct kernel_param_ops param_ops_slot_table_size = {
3305         .set = param_set_slot_table_size,
3306         .get = param_get_uint,
3307 };
3308
3309 #define param_check_slot_table_size(name, p) \
3310         __param_check(name, p, unsigned int);
3311
3312 static int param_set_max_slot_table_size(const char *val,
3313                                      const struct kernel_param *kp)
3314 {
3315         return param_set_uint_minmax(val, kp,
3316                         RPC_MIN_SLOT_TABLE,
3317                         RPC_MAX_SLOT_TABLE_LIMIT);
3318 }
3319
3320 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3321         .set = param_set_max_slot_table_size,
3322         .get = param_get_uint,
3323 };
3324
3325 #define param_check_max_slot_table_size(name, p) \
3326         __param_check(name, p, unsigned int);
3327
3328 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3329                    slot_table_size, 0644);
3330 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3331                    max_slot_table_size, 0644);
3332 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3333                    slot_table_size, 0644);