net/sunrpc/xprtsock.c

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