net/sunrpc/xprtsock.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/net/sunrpc/xprtsock.c
   4  *
   5  * Client-side transport implementation for sockets.
   6  *
   7  * TCP callback races fixes (C) 1998 Red Hat
   8  * TCP send fixes (C) 1998 Red Hat
   9  * TCP NFS related read + write fixes
  10  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11  *
  12  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13  * Fix behaviour when socket buffer is full.
  14  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15  *
  16  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17  *
  18  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19  *   <gilles.quillard@bull.net>
  20  */
  21
  22 #include <linux/types.h>
  23 #include <linux/string.h>
  24 #include <linux/slab.h>
  25 #include <linux/module.h>
  26 #include <linux/capability.h>
  27 #include <linux/pagemap.h>
  28 #include <linux/errno.h>
  29 #include <linux/socket.h>
  30 #include <linux/in.h>
  31 #include <linux/net.h>
  32 #include <linux/mm.h>
  33 #include <linux/un.h>
  34 #include <linux/udp.h>
  35 #include <linux/tcp.h>
  36 #include <linux/sunrpc/clnt.h>
  37 #include <linux/sunrpc/addr.h>
  38 #include <linux/sunrpc/sched.h>
  39 #include <linux/sunrpc/svcsock.h>
  40 #include <linux/sunrpc/xprtsock.h>
  41 #include <linux/file.h>
  42 #ifdef CONFIG_SUNRPC_BACKCHANNEL
  43 #include <linux/sunrpc/bc_xprt.h>
  44 #endif
  45
  46 #include <net/sock.h>
  47 #include <net/checksum.h>
  48 #include <net/udp.h>
  49 #include <net/tcp.h>
  50 #include <linux/bvec.h>
  51 #include <linux/uio.h>
  52
  53 #include <trace/events/sunrpc.h>
  54
  55 #include "sunrpc.h"
  56
  57 static void xs_close(struct rpc_xprt *xprt);
  58 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  59                 struct socket *sock);
  60
  61 /*
  62  * xprtsock tunables
  63  */
  64 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  65 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  66 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  67
  68 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  69 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  70
  71 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  72
  73 #define XS_TCP_LINGER_TO        (15U * HZ)
  74 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  75
  76 /*
  77  * We can register our own files under /proc/sys/sunrpc by
  78  * calling register_sysctl_table() again.  The files in that
  79  * directory become the union of all files registered there.
  80  *
  81  * We simply need to make sure that we don't collide with
  82  * someone else's file names!
  83  */
  84
  85 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  86 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  87 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  88 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  89 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  90
  91 static struct ctl_table_header *sunrpc_table_header;
  92
  93 /*
  94  * FIXME: changing the UDP slot table size should also resize the UDP
  95  *        socket buffers for existing UDP transports
  96  */
  97 static struct ctl_table xs_tunables_table[] = {
  98         {
  99                 .procname       = "udp_slot_table_entries",
 100                 .data           = &xprt_udp_slot_table_entries,
 101                 .maxlen         = sizeof(unsigned int),
 102                 .mode           = 0644,
 103                 .proc_handler   = proc_dointvec_minmax,
 104                 .extra1         = &min_slot_table_size,
 105                 .extra2         = &max_slot_table_size
 106         },
 107         {
 108                 .procname       = "tcp_slot_table_entries",
 109                 .data           = &xprt_tcp_slot_table_entries,
 110                 .maxlen         = sizeof(unsigned int),
 111                 .mode           = 0644,
 112                 .proc_handler   = proc_dointvec_minmax,
 113                 .extra1         = &min_slot_table_size,
 114                 .extra2         = &max_slot_table_size
 115         },
 116         {
 117                 .procname       = "tcp_max_slot_table_entries",
 118                 .data           = &xprt_max_tcp_slot_table_entries,
 119                 .maxlen         = sizeof(unsigned int),
 120                 .mode           = 0644,
 121                 .proc_handler   = proc_dointvec_minmax,
 122                 .extra1         = &min_slot_table_size,
 123                 .extra2         = &max_tcp_slot_table_limit
 124         },
 125         {
 126                 .procname       = "min_resvport",
 127                 .data           = &xprt_min_resvport,
 128                 .maxlen         = sizeof(unsigned int),
 129                 .mode           = 0644,
 130                 .proc_handler   = proc_dointvec_minmax,
 131                 .extra1         = &xprt_min_resvport_limit,
 132                 .extra2         = &xprt_max_resvport_limit
 133         },
 134         {
 135                 .procname       = "max_resvport",
 136                 .data           = &xprt_max_resvport,
 137                 .maxlen         = sizeof(unsigned int),
 138                 .mode           = 0644,
 139                 .proc_handler   = proc_dointvec_minmax,
 140                 .extra1         = &xprt_min_resvport_limit,
 141                 .extra2         = &xprt_max_resvport_limit
 142         },
 143         {
 144                 .procname       = "tcp_fin_timeout",
 145                 .data           = &xs_tcp_fin_timeout,
 146                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 147                 .mode           = 0644,
 148                 .proc_handler   = proc_dointvec_jiffies,
 149         },
 150         { },
 151 };
 152
 153 static struct ctl_table sunrpc_table[] = {
 154         {
 155                 .procname       = "sunrpc",
 156                 .mode           = 0555,
 157                 .child          = xs_tunables_table
 158         },
 159         { },
 160 };
 161
 162 #endif
 163
 164 /*
 165  * Wait duration for a reply from the RPC portmapper.
 166  */
 167 #define XS_BIND_TO              (60U * HZ)
 168
 169 /*
 170  * Delay if a UDP socket connect error occurs.  This is most likely some
 171  * kind of resource problem on the local host.
 172  */
 173 #define XS_UDP_REEST_TO         (2U * HZ)
 174
 175 /*
 176  * The reestablish timeout allows clients to delay for a bit before attempting
 177  * to reconnect to a server that just dropped our connection.
 178  *
 179  * We implement an exponential backoff when trying to reestablish a TCP
 180  * transport connection with the server.  Some servers like to drop a TCP
 181  * connection when they are overworked, so we start with a short timeout and
 182  * increase over time if the server is down or not responding.
 183  */
 184 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 185
 186 /*
 187  * TCP idle timeout; client drops the transport socket if it is idle
 188  * for this long.  Note that we also timeout UDP sockets to prevent
 189  * holding port numbers when there is no RPC traffic.
 190  */
 191 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 192
 193 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 194 # undef  RPC_DEBUG_DATA
 195 # define RPCDBG_FACILITY        RPCDBG_TRANS
 196 #endif
 197
 198 #ifdef RPC_DEBUG_DATA
 199 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 200 {
 201         u8 *buf = (u8 *) packet;
 202         int j;
 203
 204         dprintk("RPC:       %s\n", msg);
 205         for (j = 0; j < count && j < 128; j += 4) {
 206                 if (!(j & 31)) {
 207                         if (j)
 208                                 dprintk("\n");
 209                         dprintk("0x%04x ", j);
 210                 }
 211                 dprintk("%02x%02x%02x%02x ",
 212                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 213         }
 214         dprintk("\n");
 215 }
 216 #else
 217 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 218 {
 219         /* NOP */
 220 }
 221 #endif
 222
 223 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 224 {
 225         return (struct rpc_xprt *) sk->sk_user_data;
 226 }
 227
 228 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 229 {
 230         return (struct sockaddr *) &xprt->addr;
 231 }
 232
 233 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 234 {
 235         return (struct sockaddr_un *) &xprt->addr;
 236 }
 237
 238 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 239 {
 240         return (struct sockaddr_in *) &xprt->addr;
 241 }
 242
 243 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 244 {
 245         return (struct sockaddr_in6 *) &xprt->addr;
 246 }
 247
 248 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 249 {
 250         struct sockaddr *sap = xs_addr(xprt);
 251         struct sockaddr_in6 *sin6;
 252         struct sockaddr_in *sin;
 253         struct sockaddr_un *sun;
 254         char buf[128];
 255
 256         switch (sap->sa_family) {
 257         case AF_LOCAL:
 258                 sun = xs_addr_un(xprt);
 259                 strlcpy(buf, sun->sun_path, sizeof(buf));
 260                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 261                                                 kstrdup(buf, GFP_KERNEL);
 262                 break;
 263         case AF_INET:
 264                 (void)rpc_ntop(sap, buf, sizeof(buf));
 265                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 266                                                 kstrdup(buf, GFP_KERNEL);
 267                 sin = xs_addr_in(xprt);
 268                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 269                 break;
 270         case AF_INET6:
 271                 (void)rpc_ntop(sap, buf, sizeof(buf));
 272                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 273                                                 kstrdup(buf, GFP_KERNEL);
 274                 sin6 = xs_addr_in6(xprt);
 275                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 276                 break;
 277         default:
 278                 BUG();
 279         }
 280
 281         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 282 }
 283
 284 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 285 {
 286         struct sockaddr *sap = xs_addr(xprt);
 287         char buf[128];
 288
 289         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 290         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 291
 292         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 293         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 294 }
 295
 296 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 297                                      const char *protocol,
 298                                      const char *netid)
 299 {
 300         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 301         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 302         xs_format_common_peer_addresses(xprt);
 303         xs_format_common_peer_ports(xprt);
 304 }
 305
 306 static void xs_update_peer_port(struct rpc_xprt *xprt)
 307 {
 308         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 309         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 310
 311         xs_format_common_peer_ports(xprt);
 312 }
 313
 314 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 315 {
 316         unsigned int i;
 317
 318         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 319                 switch (i) {
 320                 case RPC_DISPLAY_PROTO:
 321                 case RPC_DISPLAY_NETID:
 322                         continue;
 323                 default:
 324                         kfree(xprt->address_strings[i]);
 325                 }
 326 }
 327
 328 static size_t
 329 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 330 {
 331         size_t i,n;
 332
 333         if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 334                 return want;
 335         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 336         for (i = 0; i < n; i++) {
 337                 if (buf->pages[i])
 338                         continue;
 339                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 340                 if (!buf->pages[i]) {
 341                         i *= PAGE_SIZE;
 342                         return i > buf->page_base ? i - buf->page_base : 0;
 343                 }
 344         }
 345         return want;
 346 }
 347
 348 static ssize_t
 349 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 350 {
 351         ssize_t ret;
 352         if (seek != 0)
 353                 iov_iter_advance(&msg->msg_iter, seek);
 354         ret = sock_recvmsg(sock, msg, flags);
 355         return ret > 0 ? ret + seek : ret;
 356 }
 357
 358 static ssize_t
 359 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 360                 struct kvec *kvec, size_t count, size_t seek)
 361 {
 362         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 363         return xs_sock_recvmsg(sock, msg, flags, seek);
 364 }
 365
 366 static ssize_t
 367 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 368                 struct bio_vec *bvec, unsigned long nr, size_t count,
 369                 size_t seek)
 370 {
 371         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 372         return xs_sock_recvmsg(sock, msg, flags, seek);
 373 }
 374
 375 static ssize_t
 376 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 377                 size_t count)
 378 {
 379         iov_iter_discard(&msg->msg_iter, READ, count);
 380         return sock_recvmsg(sock, msg, flags);
 381 }
 382
 383 static ssize_t
 384 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 385                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 386 {
 387         size_t want, seek_init = seek, offset = 0;
 388         ssize_t ret;
 389
 390         if (seek < buf->head[0].iov_len) {
 391                 want = min_t(size_t, count, buf->head[0].iov_len);
 392                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 393                 if (ret <= 0)
 394                         goto sock_err;
 395                 offset += ret;
 396                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 397                         goto out;
 398                 if (ret != want)
 399                         goto out;
 400                 seek = 0;
 401         } else {
 402                 seek -= buf->head[0].iov_len;
 403                 offset += buf->head[0].iov_len;
 404         }
 405
 406         want = xs_alloc_sparse_pages(buf,
 407                         min_t(size_t, count - offset, buf->page_len),
 408                         GFP_NOWAIT);
 409         if (seek < want) {
 410                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 411                                 xdr_buf_pagecount(buf),
 412                                 want + buf->page_base,
 413                                 seek + buf->page_base);
 414                 if (ret <= 0)
 415                         goto sock_err;
 416                 offset += ret - buf->page_base;
 417                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 418                         goto out;
 419                 if (ret != want)
 420                         goto out;
 421                 seek = 0;
 422         } else {
 423                 seek -= want;
 424                 offset += want;
 425         }
 426
 427         if (seek < buf->tail[0].iov_len) {
 428                 want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 429                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 430                 if (ret <= 0)
 431                         goto sock_err;
 432                 offset += ret;
 433                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 434                         goto out;
 435                 if (ret != want)
 436                         goto out;
 437         } else
 438                 offset += buf->tail[0].iov_len;
 439         ret = -EMSGSIZE;
 440 out:
 441         *read = offset - seek_init;
 442         return ret;
 443 sock_err:
 444         offset += seek;
 445         goto out;
 446 }
 447
 448 static void
 449 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 450 {
 451         if (!transport->recv.copied) {
 452                 if (buf->head[0].iov_len >= transport->recv.offset)
 453                         memcpy(buf->head[0].iov_base,
 454                                         &transport->recv.xid,
 455                                         transport->recv.offset);
 456                 transport->recv.copied = transport->recv.offset;
 457         }
 458 }
 459
 460 static bool
 461 xs_read_stream_request_done(struct sock_xprt *transport)
 462 {
 463         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 464 }
 465
 466 static ssize_t
 467 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 468                 int flags, struct rpc_rqst *req)
 469 {
 470         struct xdr_buf *buf = &req->rq_private_buf;
 471         size_t want, read;
 472         ssize_t ret;
 473
 474         xs_read_header(transport, buf);
 475
 476         want = transport->recv.len - transport->recv.offset;
 477         ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 478                         transport->recv.copied + want, transport->recv.copied,
 479                         &read);
 480         transport->recv.offset += read;
 481         transport->recv.copied += read;
 482         if (transport->recv.offset == transport->recv.len) {
 483                 if (xs_read_stream_request_done(transport))
 484                         msg->msg_flags |= MSG_EOR;
 485                 return read;
 486         }
 487
 488         switch (ret) {
 489         default:
 490                 break;
 491         case -EFAULT:
 492         case -EMSGSIZE:
 493                 msg->msg_flags |= MSG_TRUNC;
 494                 return read;
 495         case 0:
 496                 return -ESHUTDOWN;
 497         }
 498         return ret < 0 ? ret : read;
 499 }
 500
 501 static size_t
 502 xs_read_stream_headersize(bool isfrag)
 503 {
 504         if (isfrag)
 505                 return sizeof(__be32);
 506         return 3 * sizeof(__be32);
 507 }
 508
 509 static ssize_t
 510 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 511                 int flags, size_t want, size_t seek)
 512 {
 513         struct kvec kvec = {
 514                 .iov_base = &transport->recv.fraghdr,
 515                 .iov_len = want,
 516         };
 517         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 518 }
 519
 520 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 521 static ssize_t
 522 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 523 {
 524         struct rpc_xprt *xprt = &transport->xprt;
 525         struct rpc_rqst *req;
 526         ssize_t ret;
 527
 528         /* Look up and lock the request corresponding to the given XID */
 529         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 530         if (!req) {
 531                 printk(KERN_WARNING "Callback slot table overflowed\n");
 532                 return -ESHUTDOWN;
 533         }
 534
 535         ret = xs_read_stream_request(transport, msg, flags, req);
 536         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 537                 xprt_complete_bc_request(req, transport->recv.copied);
 538
 539         return ret;
 540 }
 541 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 542 static ssize_t
 543 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 544 {
 545         return -ESHUTDOWN;
 546 }
 547 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 548
 549 static ssize_t
 550 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 551 {
 552         struct rpc_xprt *xprt = &transport->xprt;
 553         struct rpc_rqst *req;
 554         ssize_t ret = 0;
 555
 556         /* Look up and lock the request corresponding to the given XID */
 557         spin_lock(&xprt->queue_lock);
 558         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 559         if (!req) {
 560                 msg->msg_flags |= MSG_TRUNC;
 561                 goto out;
 562         }
 563         xprt_pin_rqst(req);
 564         spin_unlock(&xprt->queue_lock);
 565
 566         ret = xs_read_stream_request(transport, msg, flags, req);
 567
 568         spin_lock(&xprt->queue_lock);
 569         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 570                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 571         xprt_unpin_rqst(req);
 572 out:
 573         spin_unlock(&xprt->queue_lock);
 574         return ret;
 575 }
 576
 577 static ssize_t
 578 xs_read_stream(struct sock_xprt *transport, int flags)
 579 {
 580         struct msghdr msg = { 0 };
 581         size_t want, read = 0;
 582         ssize_t ret = 0;
 583
 584         if (transport->recv.len == 0) {
 585                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 586                 ret = xs_read_stream_header(transport, &msg, flags, want,
 587                                 transport->recv.offset);
 588                 if (ret <= 0)
 589                         goto out_err;
 590                 transport->recv.offset = ret;
 591                 if (transport->recv.offset != want)
 592                         return transport->recv.offset;
 593                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 594                         RPC_FRAGMENT_SIZE_MASK;
 595                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 596                 read = ret;
 597         }
 598
 599         switch (be32_to_cpu(transport->recv.calldir)) {
 600         default:
 601                 msg.msg_flags |= MSG_TRUNC;
 602                 break;
 603         case RPC_CALL:
 604                 ret = xs_read_stream_call(transport, &msg, flags);
 605                 break;
 606         case RPC_REPLY:
 607                 ret = xs_read_stream_reply(transport, &msg, flags);
 608         }
 609         if (msg.msg_flags & MSG_TRUNC) {
 610                 transport->recv.calldir = cpu_to_be32(-1);
 611                 transport->recv.copied = -1;
 612         }
 613         if (ret < 0)
 614                 goto out_err;
 615         read += ret;
 616         if (transport->recv.offset < transport->recv.len) {
 617                 if (!(msg.msg_flags & MSG_TRUNC))
 618                         return read;
 619                 msg.msg_flags = 0;
 620                 ret = xs_read_discard(transport->sock, &msg, flags,
 621                                 transport->recv.len - transport->recv.offset);
 622                 if (ret <= 0)
 623                         goto out_err;
 624                 transport->recv.offset += ret;
 625                 read += ret;
 626                 if (transport->recv.offset != transport->recv.len)
 627                         return read;
 628         }
 629         if (xs_read_stream_request_done(transport)) {
 630                 trace_xs_stream_read_request(transport);
 631                 transport->recv.copied = 0;
 632         }
 633         transport->recv.offset = 0;
 634         transport->recv.len = 0;
 635         return read;
 636 out_err:
 637         return ret != 0 ? ret : -ESHUTDOWN;
 638 }
 639
 640 static void xs_stream_data_receive(struct sock_xprt *transport)
 641 {
 642         size_t read = 0;
 643         ssize_t ret = 0;
 644
 645         mutex_lock(&transport->recv_mutex);
 646         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 647         if (transport->sock == NULL)
 648                 goto out;
 649         for (;;) {
 650                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 651                 if (ret < 0)
 652                         break;
 653                 read += ret;
 654                 cond_resched();
 655         }
 656 out:
 657         mutex_unlock(&transport->recv_mutex);
 658         trace_xs_stream_read_data(&transport->xprt, ret, read);
 659 }
 660
 661 static void xs_stream_data_receive_workfn(struct work_struct *work)
 662 {
 663         struct sock_xprt *transport =
 664                 container_of(work, struct sock_xprt, recv_worker);
 665         xs_stream_data_receive(transport);
 666 }
 667
 668 static void
 669 xs_stream_reset_connect(struct sock_xprt *transport)
 670 {
 671         transport->recv.offset = 0;
 672         transport->recv.len = 0;
 673         transport->recv.copied = 0;
 674         transport->xmit.offset = 0;
 675         transport->xprt.stat.connect_count++;
 676         transport->xprt.stat.connect_start = jiffies;
 677 }
 678
 679 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 680
 681 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 682 {
 683         struct msghdr msg = {
 684                 .msg_name       = addr,
 685                 .msg_namelen    = addrlen,
 686                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 687         };
 688         struct kvec iov = {
 689                 .iov_base       = vec->iov_base + base,
 690                 .iov_len        = vec->iov_len - base,
 691         };
 692
 693         if (iov.iov_len != 0)
 694                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 695         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 696 }
 697
 698 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy, int *sent_p)
 699 {
 700         ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 701                         int offset, size_t size, int flags);
 702         struct page **ppage;
 703         unsigned int remainder;
 704         int err;
 705
 706         remainder = xdr->page_len - base;
 707         base += xdr->page_base;
 708         ppage = xdr->pages + (base >> PAGE_SHIFT);
 709         base &= ~PAGE_MASK;
 710         do_sendpage = sock->ops->sendpage;
 711         if (!zerocopy)
 712                 do_sendpage = sock_no_sendpage;
 713         for(;;) {
 714                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 715                 int flags = XS_SENDMSG_FLAGS;
 716
 717                 remainder -= len;
 718                 if (more)
 719                         flags |= MSG_MORE;
 720                 if (remainder != 0)
 721                         flags |= MSG_SENDPAGE_NOTLAST | MSG_MORE;
 722                 err = do_sendpage(sock, *ppage, base, len, flags);
 723                 if (remainder == 0 || err != len)
 724                         break;
 725                 *sent_p += err;
 726                 ppage++;
 727                 base = 0;
 728         }
 729         if (err > 0) {
 730                 *sent_p += err;
 731                 err = 0;
 732         }
 733         return err;
 734 }
 735
 736 /**
 737  * xs_sendpages - write pages directly to a socket
 738  * @sock: socket to send on
 739  * @addr: UDP only -- address of destination
 740  * @addrlen: UDP only -- length of destination address
 741  * @xdr: buffer containing this request
 742  * @base: starting position in the buffer
 743  * @zerocopy: true if it is safe to use sendpage()
 744  * @sent_p: return the total number of bytes successfully queued for sending
 745  *
 746  */
 747 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 748 {
 749         unsigned int remainder = xdr->len - base;
 750         int err = 0;
 751         int sent = 0;
 752
 753         if (unlikely(!sock))
 754                 return -ENOTSOCK;
 755
 756         if (base != 0) {
 757                 addr = NULL;
 758                 addrlen = 0;
 759         }
 760
 761         if (base < xdr->head[0].iov_len || addr != NULL) {
 762                 unsigned int len = xdr->head[0].iov_len - base;
 763                 remainder -= len;
 764                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 765                 if (remainder == 0 || err != len)
 766                         goto out;
 767                 *sent_p += err;
 768                 base = 0;
 769         } else
 770                 base -= xdr->head[0].iov_len;
 771
 772         if (base < xdr->page_len) {
 773                 unsigned int len = xdr->page_len - base;
 774                 remainder -= len;
 775                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 776                 *sent_p += sent;
 777                 if (remainder == 0 || sent != len)
 778                         goto out;
 779                 base = 0;
 780         } else
 781                 base -= xdr->page_len;
 782
 783         if (base >= xdr->tail[0].iov_len)
 784                 return 0;
 785         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 786 out:
 787         if (err > 0) {
 788                 *sent_p += err;
 789                 err = 0;
 790         }
 791         return err;
 792 }
 793
 794 /**
 795  * xs_nospace - handle transmit was incomplete
 796  * @req: pointer to RPC request
 797  *
 798  */
 799 static int xs_nospace(struct rpc_rqst *req)
 800 {
 801         struct rpc_xprt *xprt = req->rq_xprt;
 802         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 803         struct sock *sk = transport->inet;
 804         int ret = -EAGAIN;
 805
 806         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 807                         req->rq_task->tk_pid,
 808                         req->rq_slen - transport->xmit.offset,
 809                         req->rq_slen);
 810
 811         /* Protect against races with write_space */
 812         spin_lock_bh(&xprt->transport_lock);
 813
 814         /* Don't race with disconnect */
 815         if (xprt_connected(xprt)) {
 816                 /* wait for more buffer space */
 817                 sk->sk_write_pending++;
 818                 xprt_wait_for_buffer_space(xprt);
 819         } else
 820                 ret = -ENOTCONN;
 821
 822         spin_unlock_bh(&xprt->transport_lock);
 823
 824         /* Race breaker in case memory is freed before above code is called */
 825         if (ret == -EAGAIN) {
 826                 struct socket_wq *wq;
 827
 828                 rcu_read_lock();
 829                 wq = rcu_dereference(sk->sk_wq);
 830                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 831                 rcu_read_unlock();
 832
 833                 sk->sk_write_space(sk);
 834         }
 835         return ret;
 836 }
 837
 838 static void
 839 xs_stream_prepare_request(struct rpc_rqst *req)
 840 {
 841         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_NOIO);
 842 }
 843
 844 /*
 845  * Determine if the previous message in the stream was aborted before it
 846  * could complete transmission.
 847  */
 848 static bool
 849 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 850 {
 851         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 852 }
 853
 854 /*
 855  * Construct a stream transport record marker in @buf.
 856  */
 857 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 858 {
 859         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 860         rpc_fraghdr *base = buf->head[0].iov_base;
 861         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 862 }
 863
 864 /**
 865  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 866  * @req: pointer to RPC request
 867  *
 868  * Return values:
 869  *        0:    The request has been sent
 870  *   EAGAIN:    The socket was blocked, please call again later to
 871  *              complete the request
 872  * ENOTCONN:    Caller needs to invoke connect logic then call again
 873  *    other:    Some other error occured, the request was not sent
 874  */
 875 static int xs_local_send_request(struct rpc_rqst *req)
 876 {
 877         struct rpc_xprt *xprt = req->rq_xprt;
 878         struct sock_xprt *transport =
 879                                 container_of(xprt, struct sock_xprt, xprt);
 880         struct xdr_buf *xdr = &req->rq_snd_buf;
 881         int status;
 882         int sent = 0;
 883
 884         /* Close the stream if the previous transmission was incomplete */
 885         if (xs_send_request_was_aborted(transport, req)) {
 886                 xs_close(xprt);
 887                 return -ENOTCONN;
 888         }
 889
 890         xs_encode_stream_record_marker(&req->rq_snd_buf);
 891
 892         xs_pktdump("packet data:",
 893                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 894
 895         req->rq_xtime = ktime_get();
 896         status = xs_sendpages(transport->sock, NULL, 0, xdr,
 897                               transport->xmit.offset,
 898                               true, &sent);
 899         dprintk("RPC:       %s(%u) = %d\n",
 900                         __func__, xdr->len - transport->xmit.offset, status);
 901
 902         if (status == -EAGAIN && sock_writeable(transport->inet))
 903                 status = -ENOBUFS;
 904
 905         if (likely(sent > 0) || status == 0) {
 906                 transport->xmit.offset += sent;
 907                 req->rq_bytes_sent = transport->xmit.offset;
 908                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 909                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 910                         req->rq_bytes_sent = 0;
 911                         transport->xmit.offset = 0;
 912                         return 0;
 913                 }
 914                 status = -EAGAIN;
 915         }
 916
 917         switch (status) {
 918         case -ENOBUFS:
 919                 break;
 920         case -EAGAIN:
 921                 status = xs_nospace(req);
 922                 break;
 923         default:
 924                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 925                         -status);
 926                 /* fall through */
 927         case -EPIPE:
 928                 xs_close(xprt);
 929                 status = -ENOTCONN;
 930         }
 931
 932         return status;
 933 }
 934
 935 /**
 936  * xs_udp_send_request - write an RPC request to a UDP socket
 937  * @req: pointer to RPC request
 938  *
 939  * Return values:
 940  *        0:    The request has been sent
 941  *   EAGAIN:    The socket was blocked, please call again later to
 942  *              complete the request
 943  * ENOTCONN:    Caller needs to invoke connect logic then call again
 944  *    other:    Some other error occurred, the request was not sent
 945  */
 946 static int xs_udp_send_request(struct rpc_rqst *req)
 947 {
 948         struct rpc_xprt *xprt = req->rq_xprt;
 949         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 950         struct xdr_buf *xdr = &req->rq_snd_buf;
 951         int sent = 0;
 952         int status;
 953
 954         xs_pktdump("packet data:",
 955                                 req->rq_svec->iov_base,
 956                                 req->rq_svec->iov_len);
 957
 958         if (!xprt_bound(xprt))
 959                 return -ENOTCONN;
 960
 961         if (!xprt_request_get_cong(xprt, req))
 962                 return -EBADSLT;
 963
 964         req->rq_xtime = ktime_get();
 965         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 966                               xdr, 0, true, &sent);
 967
 968         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 969                         xdr->len, status);
 970
 971         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 972         if (status == -EPERM)
 973                 goto process_status;
 974
 975         if (status == -EAGAIN && sock_writeable(transport->inet))
 976                 status = -ENOBUFS;
 977
 978         if (sent > 0 || status == 0) {
 979                 req->rq_xmit_bytes_sent += sent;
 980                 if (sent >= req->rq_slen)
 981                         return 0;
 982                 /* Still some bytes left; set up for a retry later. */
 983                 status = -EAGAIN;
 984         }
 985
 986 process_status:
 987         switch (status) {
 988         case -ENOTSOCK:
 989                 status = -ENOTCONN;
 990                 /* Should we call xs_close() here? */
 991                 break;
 992         case -EAGAIN:
 993                 status = xs_nospace(req);
 994                 break;
 995         case -ENETUNREACH:
 996         case -ENOBUFS:
 997         case -EPIPE:
 998         case -ECONNREFUSED:
 999         case -EPERM:
1000                 /* When the server has died, an ICMP port unreachable message
1001                  * prompts ECONNREFUSED. */
1002                 break;
1003         default:
1004                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1005                         -status);
1006         }
1007
1008         return status;
1009 }
1010
1011 /**
1012  * xs_tcp_send_request - write an RPC request to a TCP socket
1013  * @req: pointer to RPC request
1014  *
1015  * Return values:
1016  *        0:    The request has been sent
1017  *   EAGAIN:    The socket was blocked, please call again later to
1018  *              complete the request
1019  * ENOTCONN:    Caller needs to invoke connect logic then call again
1020  *    other:    Some other error occurred, the request was not sent
1021  *
1022  * XXX: In the case of soft timeouts, should we eventually give up
1023  *      if sendmsg is not able to make progress?
1024  */
1025 static int xs_tcp_send_request(struct rpc_rqst *req)
1026 {
1027         struct rpc_xprt *xprt = req->rq_xprt;
1028         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1029         struct xdr_buf *xdr = &req->rq_snd_buf;
1030         bool zerocopy = true;
1031         bool vm_wait = false;
1032         int status;
1033         int sent;
1034
1035         /* Close the stream if the previous transmission was incomplete */
1036         if (xs_send_request_was_aborted(transport, req)) {
1037                 if (transport->sock != NULL)
1038                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1039                 return -ENOTCONN;
1040         }
1041
1042         xs_encode_stream_record_marker(&req->rq_snd_buf);
1043
1044         xs_pktdump("packet data:",
1045                                 req->rq_svec->iov_base,
1046                                 req->rq_svec->iov_len);
1047         /* Don't use zero copy if this is a resend. If the RPC call
1048          * completes while the socket holds a reference to the pages,
1049          * then we may end up resending corrupted data.
1050          */
1051         if (req->rq_task->tk_flags & RPC_TASK_SENT)
1052                 zerocopy = false;
1053
1054         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1055                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1056
1057         /* Continue transmitting the packet/record. We must be careful
1058          * to cope with writespace callbacks arriving _after_ we have
1059          * called sendmsg(). */
1060         req->rq_xtime = ktime_get();
1061         while (1) {
1062                 sent = 0;
1063                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
1064                                       transport->xmit.offset,
1065                                       zerocopy, &sent);
1066
1067                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1068                                 xdr->len - transport->xmit.offset, status);
1069
1070                 /* If we've sent the entire packet, immediately
1071                  * reset the count of bytes sent. */
1072                 transport->xmit.offset += sent;
1073                 req->rq_bytes_sent = transport->xmit.offset;
1074                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
1075                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1076                         req->rq_bytes_sent = 0;
1077                         transport->xmit.offset = 0;
1078                         return 0;
1079                 }
1080
1081                 WARN_ON_ONCE(sent == 0 && status == 0);
1082
1083                 if (status == -EAGAIN ) {
1084                         /*
1085                          * Return EAGAIN if we're sure we're hitting the
1086                          * socket send buffer limits.
1087                          */
1088                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1089                                 break;
1090                         /*
1091                          * Did we hit a memory allocation failure?
1092                          */
1093                         if (sent == 0) {
1094                                 status = -ENOBUFS;
1095                                 if (vm_wait)
1096                                         break;
1097                                 /* Retry, knowing now that we're below the
1098                                  * socket send buffer limit
1099                                  */
1100                                 vm_wait = true;
1101                         }
1102                         continue;
1103                 }
1104                 if (status < 0)
1105                         break;
1106                 vm_wait = false;
1107         }
1108
1109         switch (status) {
1110         case -ENOTSOCK:
1111                 status = -ENOTCONN;
1112                 /* Should we call xs_close() here? */
1113                 break;
1114         case -EAGAIN:
1115                 status = xs_nospace(req);
1116                 break;
1117         case -ECONNRESET:
1118         case -ECONNREFUSED:
1119         case -ENOTCONN:
1120         case -EADDRINUSE:
1121         case -ENOBUFS:
1122         case -EPIPE:
1123                 break;
1124         default:
1125                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1126                         -status);
1127         }
1128
1129         return status;
1130 }
1131
1132 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1133 {
1134         transport->old_data_ready = sk->sk_data_ready;
1135         transport->old_state_change = sk->sk_state_change;
1136         transport->old_write_space = sk->sk_write_space;
1137         transport->old_error_report = sk->sk_error_report;
1138 }
1139
1140 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1141 {
1142         sk->sk_data_ready = transport->old_data_ready;
1143         sk->sk_state_change = transport->old_state_change;
1144         sk->sk_write_space = transport->old_write_space;
1145         sk->sk_error_report = transport->old_error_report;
1146 }
1147
1148 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1149 {
1150         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1151
1152         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1153 }
1154
1155 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1156 {
1157         smp_mb__before_atomic();
1158         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1159         clear_bit(XPRT_CLOSING, &xprt->state);
1160         xs_sock_reset_state_flags(xprt);
1161         smp_mb__after_atomic();
1162 }
1163
1164 /**
1165  * xs_error_report - callback to handle TCP socket state errors
1166  * @sk: socket
1167  *
1168  * Note: we don't call sock_error() since there may be a rpc_task
1169  * using the socket, and so we don't want to clear sk->sk_err.
1170  */
1171 static void xs_error_report(struct sock *sk)
1172 {
1173         struct rpc_xprt *xprt;
1174         int err;
1175
1176         read_lock_bh(&sk->sk_callback_lock);
1177         if (!(xprt = xprt_from_sock(sk)))
1178                 goto out;
1179
1180         err = -sk->sk_err;
1181         if (err == 0)
1182                 goto out;
1183         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1184                         xprt, -err);
1185         trace_rpc_socket_error(xprt, sk->sk_socket, err);
1186         xprt_wake_pending_tasks(xprt, err);
1187  out:
1188         read_unlock_bh(&sk->sk_callback_lock);
1189 }
1190
1191 static void xs_reset_transport(struct sock_xprt *transport)
1192 {
1193         struct socket *sock = transport->sock;
1194         struct sock *sk = transport->inet;
1195         struct rpc_xprt *xprt = &transport->xprt;
1196
1197         if (sk == NULL)
1198                 return;
1199
1200         if (atomic_read(&transport->xprt.swapper))
1201                 sk_clear_memalloc(sk);
1202
1203         kernel_sock_shutdown(sock, SHUT_RDWR);
1204
1205         mutex_lock(&transport->recv_mutex);
1206         write_lock_bh(&sk->sk_callback_lock);
1207         transport->inet = NULL;
1208         transport->sock = NULL;
1209
1210         sk->sk_user_data = NULL;
1211
1212         xs_restore_old_callbacks(transport, sk);
1213         xprt_clear_connected(xprt);
1214         write_unlock_bh(&sk->sk_callback_lock);
1215         xs_sock_reset_connection_flags(xprt);
1216         mutex_unlock(&transport->recv_mutex);
1217
1218         trace_rpc_socket_close(xprt, sock);
1219         sock_release(sock);
1220
1221         xprt_disconnect_done(xprt);
1222 }
1223
1224 /**
1225  * xs_close - close a socket
1226  * @xprt: transport
1227  *
1228  * This is used when all requests are complete; ie, no DRC state remains
1229  * on the server we want to save.
1230  *
1231  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1232  * xs_reset_transport() zeroing the socket from underneath a writer.
1233  */
1234 static void xs_close(struct rpc_xprt *xprt)
1235 {
1236         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1237
1238         dprintk("RPC:       xs_close xprt %p\n", xprt);
1239
1240         xs_reset_transport(transport);
1241         xprt->reestablish_timeout = 0;
1242 }
1243
1244 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1245 {
1246         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1247                 xprt);
1248         xprt_disconnect_done(xprt);
1249 }
1250
1251 static void xs_xprt_free(struct rpc_xprt *xprt)
1252 {
1253         xs_free_peer_addresses(xprt);
1254         xprt_free(xprt);
1255 }
1256
1257 /**
1258  * xs_destroy - prepare to shutdown a transport
1259  * @xprt: doomed transport
1260  *
1261  */
1262 static void xs_destroy(struct rpc_xprt *xprt)
1263 {
1264         struct sock_xprt *transport = container_of(xprt,
1265                         struct sock_xprt, xprt);
1266         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1267
1268         cancel_delayed_work_sync(&transport->connect_worker);
1269         xs_close(xprt);
1270         cancel_work_sync(&transport->recv_worker);
1271         xs_xprt_free(xprt);
1272         module_put(THIS_MODULE);
1273 }
1274
1275 /**
1276  * xs_udp_data_read_skb - receive callback for UDP sockets
1277  * @xprt: transport
1278  * @sk: socket
1279  * @skb: skbuff
1280  *
1281  */
1282 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1283                 struct sock *sk,
1284                 struct sk_buff *skb)
1285 {
1286         struct rpc_task *task;
1287         struct rpc_rqst *rovr;
1288         int repsize, copied;
1289         u32 _xid;
1290         __be32 *xp;
1291
1292         repsize = skb->len;
1293         if (repsize < 4) {
1294                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1295                 return;
1296         }
1297
1298         /* Copy the XID from the skb... */
1299         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1300         if (xp == NULL)
1301                 return;
1302
1303         /* Look up and lock the request corresponding to the given XID */
1304         spin_lock(&xprt->queue_lock);
1305         rovr = xprt_lookup_rqst(xprt, *xp);
1306         if (!rovr)
1307                 goto out_unlock;
1308         xprt_pin_rqst(rovr);
1309         xprt_update_rtt(rovr->rq_task);
1310         spin_unlock(&xprt->queue_lock);
1311         task = rovr->rq_task;
1312
1313         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1314                 copied = repsize;
1315
1316         /* Suck it into the iovec, verify checksum if not done by hw. */
1317         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1318                 spin_lock(&xprt->queue_lock);
1319                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1320                 goto out_unpin;
1321         }
1322
1323
1324         spin_lock_bh(&xprt->transport_lock);
1325         xprt_adjust_cwnd(xprt, task, copied);
1326         spin_unlock_bh(&xprt->transport_lock);
1327         spin_lock(&xprt->queue_lock);
1328         xprt_complete_rqst(task, copied);
1329         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1330 out_unpin:
1331         xprt_unpin_rqst(rovr);
1332  out_unlock:
1333         spin_unlock(&xprt->queue_lock);
1334 }
1335
1336 static void xs_udp_data_receive(struct sock_xprt *transport)
1337 {
1338         struct sk_buff *skb;
1339         struct sock *sk;
1340         int err;
1341
1342         mutex_lock(&transport->recv_mutex);
1343         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1344         sk = transport->inet;
1345         if (sk == NULL)
1346                 goto out;
1347         for (;;) {
1348                 skb = skb_recv_udp(sk, 0, 1, &err);
1349                 if (skb == NULL)
1350                         break;
1351                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1352                 consume_skb(skb);
1353                 cond_resched();
1354         }
1355 out:
1356         mutex_unlock(&transport->recv_mutex);
1357 }
1358
1359 static void xs_udp_data_receive_workfn(struct work_struct *work)
1360 {
1361         struct sock_xprt *transport =
1362                 container_of(work, struct sock_xprt, recv_worker);
1363         xs_udp_data_receive(transport);
1364 }
1365
1366 /**
1367  * xs_data_ready - "data ready" callback for UDP sockets
1368  * @sk: socket with data to read
1369  *
1370  */
1371 static void xs_data_ready(struct sock *sk)
1372 {
1373         struct rpc_xprt *xprt;
1374
1375         read_lock_bh(&sk->sk_callback_lock);
1376         dprintk("RPC:       xs_data_ready...\n");
1377         xprt = xprt_from_sock(sk);
1378         if (xprt != NULL) {
1379                 struct sock_xprt *transport = container_of(xprt,
1380                                 struct sock_xprt, xprt);
1381                 transport->old_data_ready(sk);
1382                 /* Any data means we had a useful conversation, so
1383                  * then we don't need to delay the next reconnect
1384                  */
1385                 if (xprt->reestablish_timeout)
1386                         xprt->reestablish_timeout = 0;
1387                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1388                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1389         }
1390         read_unlock_bh(&sk->sk_callback_lock);
1391 }
1392
1393 /*
1394  * Helper function to force a TCP close if the server is sending
1395  * junk and/or it has put us in CLOSE_WAIT
1396  */
1397 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1398 {
1399         xprt_force_disconnect(xprt);
1400 }
1401
1402 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1403 static int xs_tcp_bc_up(struct svc_serv *serv, struct net *net)
1404 {
1405         int ret;
1406
1407         ret = svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
1408                               SVC_SOCK_ANONYMOUS);
1409         if (ret < 0)
1410                 return ret;
1411         return 0;
1412 }
1413
1414 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1415 {
1416         return PAGE_SIZE;
1417 }
1418 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1419
1420 /**
1421  * xs_tcp_state_change - callback to handle TCP socket state changes
1422  * @sk: socket whose state has changed
1423  *
1424  */
1425 static void xs_tcp_state_change(struct sock *sk)
1426 {
1427         struct rpc_xprt *xprt;
1428         struct sock_xprt *transport;
1429
1430         read_lock_bh(&sk->sk_callback_lock);
1431         if (!(xprt = xprt_from_sock(sk)))
1432                 goto out;
1433         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1434         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1435                         sk->sk_state, xprt_connected(xprt),
1436                         sock_flag(sk, SOCK_DEAD),
1437                         sock_flag(sk, SOCK_ZAPPED),
1438                         sk->sk_shutdown);
1439
1440         transport = container_of(xprt, struct sock_xprt, xprt);
1441         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1442         switch (sk->sk_state) {
1443         case TCP_ESTABLISHED:
1444                 spin_lock(&xprt->transport_lock);
1445                 if (!xprt_test_and_set_connected(xprt)) {
1446                         xprt->connect_cookie++;
1447                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1448                         xprt_clear_connecting(xprt);
1449
1450                         xprt->stat.connect_count++;
1451                         xprt->stat.connect_time += (long)jiffies -
1452                                                    xprt->stat.connect_start;
1453                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1454                 }
1455                 spin_unlock(&xprt->transport_lock);
1456                 break;
1457         case TCP_FIN_WAIT1:
1458                 /* The client initiated a shutdown of the socket */
1459                 xprt->connect_cookie++;
1460                 xprt->reestablish_timeout = 0;
1461                 set_bit(XPRT_CLOSING, &xprt->state);
1462                 smp_mb__before_atomic();
1463                 clear_bit(XPRT_CONNECTED, &xprt->state);
1464                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1465                 smp_mb__after_atomic();
1466                 break;
1467         case TCP_CLOSE_WAIT:
1468                 /* The server initiated a shutdown of the socket */
1469                 xprt->connect_cookie++;
1470                 clear_bit(XPRT_CONNECTED, &xprt->state);
1471                 xs_tcp_force_close(xprt);
1472                 /* fall through */
1473         case TCP_CLOSING:
1474                 /*
1475                  * If the server closed down the connection, make sure that
1476                  * we back off before reconnecting
1477                  */
1478                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1479                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1480                 break;
1481         case TCP_LAST_ACK:
1482                 set_bit(XPRT_CLOSING, &xprt->state);
1483                 smp_mb__before_atomic();
1484                 clear_bit(XPRT_CONNECTED, &xprt->state);
1485                 smp_mb__after_atomic();
1486                 break;
1487         case TCP_CLOSE:
1488                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1489                                         &transport->sock_state))
1490                         xprt_clear_connecting(xprt);
1491                 clear_bit(XPRT_CLOSING, &xprt->state);
1492                 /* Trigger the socket release */
1493                 xs_tcp_force_close(xprt);
1494         }
1495  out:
1496         read_unlock_bh(&sk->sk_callback_lock);
1497 }
1498
1499 static void xs_write_space(struct sock *sk)
1500 {
1501         struct socket_wq *wq;
1502         struct rpc_xprt *xprt;
1503
1504         if (!sk->sk_socket)
1505                 return;
1506         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1507
1508         if (unlikely(!(xprt = xprt_from_sock(sk))))
1509                 return;
1510         rcu_read_lock();
1511         wq = rcu_dereference(sk->sk_wq);
1512         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1513                 goto out;
1514
1515         if (xprt_write_space(xprt))
1516                 sk->sk_write_pending--;
1517 out:
1518         rcu_read_unlock();
1519 }
1520
1521 /**
1522  * xs_udp_write_space - callback invoked when socket buffer space
1523  *                             becomes available
1524  * @sk: socket whose state has changed
1525  *
1526  * Called when more output buffer space is available for this socket.
1527  * We try not to wake our writers until they can make "significant"
1528  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1529  * with a bunch of small requests.
1530  */
1531 static void xs_udp_write_space(struct sock *sk)
1532 {
1533         read_lock_bh(&sk->sk_callback_lock);
1534
1535         /* from net/core/sock.c:sock_def_write_space */
1536         if (sock_writeable(sk))
1537                 xs_write_space(sk);
1538
1539         read_unlock_bh(&sk->sk_callback_lock);
1540 }
1541
1542 /**
1543  * xs_tcp_write_space - callback invoked when socket buffer space
1544  *                             becomes available
1545  * @sk: socket whose state has changed
1546  *
1547  * Called when more output buffer space is available for this socket.
1548  * We try not to wake our writers until they can make "significant"
1549  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1550  * with a bunch of small requests.
1551  */
1552 static void xs_tcp_write_space(struct sock *sk)
1553 {
1554         read_lock_bh(&sk->sk_callback_lock);
1555
1556         /* from net/core/stream.c:sk_stream_write_space */
1557         if (sk_stream_is_writeable(sk))
1558                 xs_write_space(sk);
1559
1560         read_unlock_bh(&sk->sk_callback_lock);
1561 }
1562
1563 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1564 {
1565         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1566         struct sock *sk = transport->inet;
1567
1568         if (transport->rcvsize) {
1569                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1570                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1571         }
1572         if (transport->sndsize) {
1573                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1574                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1575                 sk->sk_write_space(sk);
1576         }
1577 }
1578
1579 /**
1580  * xs_udp_set_buffer_size - set send and receive limits
1581  * @xprt: generic transport
1582  * @sndsize: requested size of send buffer, in bytes
1583  * @rcvsize: requested size of receive buffer, in bytes
1584  *
1585  * Set socket send and receive buffer size limits.
1586  */
1587 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1588 {
1589         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1590
1591         transport->sndsize = 0;
1592         if (sndsize)
1593                 transport->sndsize = sndsize + 1024;
1594         transport->rcvsize = 0;
1595         if (rcvsize)
1596                 transport->rcvsize = rcvsize + 1024;
1597
1598         xs_udp_do_set_buffer_size(xprt);
1599 }
1600
1601 /**
1602  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1603  * @task: task that timed out
1604  *
1605  * Adjust the congestion window after a retransmit timeout has occurred.
1606  */
1607 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1608 {
1609         spin_lock_bh(&xprt->transport_lock);
1610         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1611         spin_unlock_bh(&xprt->transport_lock);
1612 }
1613
1614 static int xs_get_random_port(void)
1615 {
1616         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1617         unsigned short range;
1618         unsigned short rand;
1619
1620         if (max < min)
1621                 return -EADDRINUSE;
1622         range = max - min + 1;
1623         rand = (unsigned short) prandom_u32() % range;
1624         return rand + min;
1625 }
1626
1627 /**
1628  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1629  * @sock: socket
1630  *
1631  * Note that this function has to be called on all sockets that share the
1632  * same port, and it must be called before binding.
1633  */
1634 static void xs_sock_set_reuseport(struct socket *sock)
1635 {
1636         int opt = 1;
1637
1638         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1639                         (char *)&opt, sizeof(opt));
1640 }
1641
1642 static unsigned short xs_sock_getport(struct socket *sock)
1643 {
1644         struct sockaddr_storage buf;
1645         unsigned short port = 0;
1646
1647         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1648                 goto out;
1649         switch (buf.ss_family) {
1650         case AF_INET6:
1651                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1652                 break;
1653         case AF_INET:
1654                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1655         }
1656 out:
1657         return port;
1658 }
1659
1660 /**
1661  * xs_set_port - reset the port number in the remote endpoint address
1662  * @xprt: generic transport
1663  * @port: new port number
1664  *
1665  */
1666 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1667 {
1668         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1669
1670         rpc_set_port(xs_addr(xprt), port);
1671         xs_update_peer_port(xprt);
1672 }
1673
1674 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1675 {
1676         if (transport->srcport == 0)
1677                 transport->srcport = xs_sock_getport(sock);
1678 }
1679
1680 static int xs_get_srcport(struct sock_xprt *transport)
1681 {
1682         int port = transport->srcport;
1683
1684         if (port == 0 && transport->xprt.resvport)
1685                 port = xs_get_random_port();
1686         return port;
1687 }
1688
1689 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1690 {
1691         if (transport->srcport != 0)
1692                 transport->srcport = 0;
1693         if (!transport->xprt.resvport)
1694                 return 0;
1695         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1696                 return xprt_max_resvport;
1697         return --port;
1698 }
1699 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1700 {
1701         struct sockaddr_storage myaddr;
1702         int err, nloop = 0;
1703         int port = xs_get_srcport(transport);
1704         unsigned short last;
1705
1706         /*
1707          * If we are asking for any ephemeral port (i.e. port == 0 &&
1708          * transport->xprt.resvport == 0), don't bind.  Let the local
1709          * port selection happen implicitly when the socket is used
1710          * (for example at connect time).
1711          *
1712          * This ensures that we can continue to establish TCP
1713          * connections even when all local ephemeral ports are already
1714          * a part of some TCP connection.  This makes no difference
1715          * for UDP sockets, but also doens't harm them.
1716          *
1717          * If we're asking for any reserved port (i.e. port == 0 &&
1718          * transport->xprt.resvport == 1) xs_get_srcport above will
1719          * ensure that port is non-zero and we will bind as needed.
1720          */
1721         if (port <= 0)
1722                 return port;
1723
1724         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1725         do {
1726                 rpc_set_port((struct sockaddr *)&myaddr, port);
1727                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1728                                 transport->xprt.addrlen);
1729                 if (err == 0) {
1730                         transport->srcport = port;
1731                         break;
1732                 }
1733                 last = port;
1734                 port = xs_next_srcport(transport, port);
1735                 if (port > last)
1736                         nloop++;
1737         } while (err == -EADDRINUSE && nloop != 2);
1738
1739         if (myaddr.ss_family == AF_INET)
1740                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1741                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1742                                 port, err ? "failed" : "ok", err);
1743         else
1744                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1745                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1746                                 port, err ? "failed" : "ok", err);
1747         return err;
1748 }
1749
1750 /*
1751  * We don't support autobind on AF_LOCAL sockets
1752  */
1753 static void xs_local_rpcbind(struct rpc_task *task)
1754 {
1755         xprt_set_bound(task->tk_xprt);
1756 }
1757
1758 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1759 {
1760 }
1761
1762 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1763 static struct lock_class_key xs_key[2];
1764 static struct lock_class_key xs_slock_key[2];
1765
1766 static inline void xs_reclassify_socketu(struct socket *sock)
1767 {
1768         struct sock *sk = sock->sk;
1769
1770         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1771                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1772 }
1773
1774 static inline void xs_reclassify_socket4(struct socket *sock)
1775 {
1776         struct sock *sk = sock->sk;
1777
1778         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1779                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1780 }
1781
1782 static inline void xs_reclassify_socket6(struct socket *sock)
1783 {
1784         struct sock *sk = sock->sk;
1785
1786         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1787                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1788 }
1789
1790 static inline void xs_reclassify_socket(int family, struct socket *sock)
1791 {
1792         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1793                 return;
1794
1795         switch (family) {
1796         case AF_LOCAL:
1797                 xs_reclassify_socketu(sock);
1798                 break;
1799         case AF_INET:
1800                 xs_reclassify_socket4(sock);
1801                 break;
1802         case AF_INET6:
1803                 xs_reclassify_socket6(sock);
1804                 break;
1805         }
1806 }
1807 #else
1808 static inline void xs_reclassify_socket(int family, struct socket *sock)
1809 {
1810 }
1811 #endif
1812
1813 static void xs_dummy_setup_socket(struct work_struct *work)
1814 {
1815 }
1816
1817 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1818                 struct sock_xprt *transport, int family, int type,
1819                 int protocol, bool reuseport)
1820 {
1821         struct socket *sock;
1822         int err;
1823
1824         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1825         if (err < 0) {
1826                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1827                                 protocol, -err);
1828                 goto out;
1829         }
1830         xs_reclassify_socket(family, sock);
1831
1832         if (reuseport)
1833                 xs_sock_set_reuseport(sock);
1834
1835         err = xs_bind(transport, sock);
1836         if (err) {
1837                 sock_release(sock);
1838                 goto out;
1839         }
1840
1841         return sock;
1842 out:
1843         return ERR_PTR(err);
1844 }
1845
1846 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1847                                       struct socket *sock)
1848 {
1849         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1850                                                                         xprt);
1851
1852         if (!transport->inet) {
1853                 struct sock *sk = sock->sk;
1854
1855                 write_lock_bh(&sk->sk_callback_lock);
1856
1857                 xs_save_old_callbacks(transport, sk);
1858
1859                 sk->sk_user_data = xprt;
1860                 sk->sk_data_ready = xs_data_ready;
1861                 sk->sk_write_space = xs_udp_write_space;
1862                 sock_set_flag(sk, SOCK_FASYNC);
1863                 sk->sk_error_report = xs_error_report;
1864                 sk->sk_allocation = GFP_NOIO;
1865
1866                 xprt_clear_connected(xprt);
1867
1868                 /* Reset to new socket */
1869                 transport->sock = sock;
1870                 transport->inet = sk;
1871
1872                 write_unlock_bh(&sk->sk_callback_lock);
1873         }
1874
1875         xs_stream_reset_connect(transport);
1876
1877         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1878 }
1879
1880 /**
1881  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1882  * @transport: socket transport to connect
1883  */
1884 static int xs_local_setup_socket(struct sock_xprt *transport)
1885 {
1886         struct rpc_xprt *xprt = &transport->xprt;
1887         struct socket *sock;
1888         int status = -EIO;
1889
1890         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1891                                         SOCK_STREAM, 0, &sock, 1);
1892         if (status < 0) {
1893                 dprintk("RPC:       can't create AF_LOCAL "
1894                         "transport socket (%d).\n", -status);
1895                 goto out;
1896         }
1897         xs_reclassify_socket(AF_LOCAL, sock);
1898
1899         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1900                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1901
1902         status = xs_local_finish_connecting(xprt, sock);
1903         trace_rpc_socket_connect(xprt, sock, status);
1904         switch (status) {
1905         case 0:
1906                 dprintk("RPC:       xprt %p connected to %s\n",
1907                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1908                 xprt->stat.connect_count++;
1909                 xprt->stat.connect_time += (long)jiffies -
1910                                            xprt->stat.connect_start;
1911                 xprt_set_connected(xprt);
1912         case -ENOBUFS:
1913                 break;
1914         case -ENOENT:
1915                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1916                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1917                 break;
1918         case -ECONNREFUSED:
1919                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1920                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1921                 break;
1922         default:
1923                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1924                                 __func__, -status,
1925                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1926         }
1927
1928 out:
1929         xprt_clear_connecting(xprt);
1930         xprt_wake_pending_tasks(xprt, status);
1931         return status;
1932 }
1933
1934 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1935 {
1936         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1937         int ret;
1938
1939          if (RPC_IS_ASYNC(task)) {
1940                 /*
1941                  * We want the AF_LOCAL connect to be resolved in the
1942                  * filesystem namespace of the process making the rpc
1943                  * call.  Thus we connect synchronously.
1944                  *
1945                  * If we want to support asynchronous AF_LOCAL calls,
1946                  * we'll need to figure out how to pass a namespace to
1947                  * connect.
1948                  */
1949                 rpc_exit(task, -ENOTCONN);
1950                 return;
1951         }
1952         ret = xs_local_setup_socket(transport);
1953         if (ret && !RPC_IS_SOFTCONN(task))
1954                 msleep_interruptible(15000);
1955 }
1956
1957 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1958 /*
1959  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1960  * know that we have exclusive access to the socket), to guard against
1961  * races with xs_reset_transport.
1962  */
1963 static void xs_set_memalloc(struct rpc_xprt *xprt)
1964 {
1965         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1966                         xprt);
1967
1968         /*
1969          * If there's no sock, then we have nothing to set. The
1970          * reconnecting process will get it for us.
1971          */
1972         if (!transport->inet)
1973                 return;
1974         if (atomic_read(&xprt->swapper))
1975                 sk_set_memalloc(transport->inet);
1976 }
1977
1978 /**
1979  * xs_enable_swap - Tag this transport as being used for swap.
1980  * @xprt: transport to tag
1981  *
1982  * Take a reference to this transport on behalf of the rpc_clnt, and
1983  * optionally mark it for swapping if it wasn't already.
1984  */
1985 static int
1986 xs_enable_swap(struct rpc_xprt *xprt)
1987 {
1988         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1989
1990         if (atomic_inc_return(&xprt->swapper) != 1)
1991                 return 0;
1992         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1993                 return -ERESTARTSYS;
1994         if (xs->inet)
1995                 sk_set_memalloc(xs->inet);
1996         xprt_release_xprt(xprt, NULL);
1997         return 0;
1998 }
1999
2000 /**
2001  * xs_disable_swap - Untag this transport as being used for swap.
2002  * @xprt: transport to tag
2003  *
2004  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2005  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2006  */
2007 static void
2008 xs_disable_swap(struct rpc_xprt *xprt)
2009 {
2010         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2011
2012         if (!atomic_dec_and_test(&xprt->swapper))
2013                 return;
2014         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2015                 return;
2016         if (xs->inet)
2017                 sk_clear_memalloc(xs->inet);
2018         xprt_release_xprt(xprt, NULL);
2019 }
2020 #else
2021 static void xs_set_memalloc(struct rpc_xprt *xprt)
2022 {
2023 }
2024
2025 static int
2026 xs_enable_swap(struct rpc_xprt *xprt)
2027 {
2028         return -EINVAL;
2029 }
2030
2031 static void
2032 xs_disable_swap(struct rpc_xprt *xprt)
2033 {
2034 }
2035 #endif
2036
2037 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2038 {
2039         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2040
2041         if (!transport->inet) {
2042                 struct sock *sk = sock->sk;
2043
2044                 write_lock_bh(&sk->sk_callback_lock);
2045
2046                 xs_save_old_callbacks(transport, sk);
2047
2048                 sk->sk_user_data = xprt;
2049                 sk->sk_data_ready = xs_data_ready;
2050                 sk->sk_write_space = xs_udp_write_space;
2051                 sock_set_flag(sk, SOCK_FASYNC);
2052                 sk->sk_allocation = GFP_NOIO;
2053
2054                 xprt_set_connected(xprt);
2055
2056                 /* Reset to new socket */
2057                 transport->sock = sock;
2058                 transport->inet = sk;
2059
2060                 xs_set_memalloc(xprt);
2061
2062                 write_unlock_bh(&sk->sk_callback_lock);
2063         }
2064         xs_udp_do_set_buffer_size(xprt);
2065
2066         xprt->stat.connect_start = jiffies;
2067 }
2068
2069 static void xs_udp_setup_socket(struct work_struct *work)
2070 {
2071         struct sock_xprt *transport =
2072                 container_of(work, struct sock_xprt, connect_worker.work);
2073         struct rpc_xprt *xprt = &transport->xprt;
2074         struct socket *sock;
2075         int status = -EIO;
2076
2077         sock = xs_create_sock(xprt, transport,
2078                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2079                         IPPROTO_UDP, false);
2080         if (IS_ERR(sock))
2081                 goto out;
2082
2083         dprintk("RPC:       worker connecting xprt %p via %s to "
2084                                 "%s (port %s)\n", xprt,
2085                         xprt->address_strings[RPC_DISPLAY_PROTO],
2086                         xprt->address_strings[RPC_DISPLAY_ADDR],
2087                         xprt->address_strings[RPC_DISPLAY_PORT]);
2088
2089         xs_udp_finish_connecting(xprt, sock);
2090         trace_rpc_socket_connect(xprt, sock, 0);
2091         status = 0;
2092 out:
2093         xprt_clear_connecting(xprt);
2094         xprt_unlock_connect(xprt, transport);
2095         xprt_wake_pending_tasks(xprt, status);
2096 }
2097
2098 /**
2099  * xs_tcp_shutdown - gracefully shut down a TCP socket
2100  * @xprt: transport
2101  *
2102  * Initiates a graceful shutdown of the TCP socket by calling the
2103  * equivalent of shutdown(SHUT_RDWR);
2104  */
2105 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2106 {
2107         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2108         struct socket *sock = transport->sock;
2109         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2110
2111         if (sock == NULL)
2112                 return;
2113         switch (skst) {
2114         default:
2115                 kernel_sock_shutdown(sock, SHUT_RDWR);
2116                 trace_rpc_socket_shutdown(xprt, sock);
2117                 break;
2118         case TCP_CLOSE:
2119         case TCP_TIME_WAIT:
2120                 xs_reset_transport(transport);
2121         }
2122 }
2123
2124 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2125                 struct socket *sock)
2126 {
2127         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2128         unsigned int keepidle;
2129         unsigned int keepcnt;
2130         unsigned int opt_on = 1;
2131         unsigned int timeo;
2132
2133         spin_lock_bh(&xprt->transport_lock);
2134         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2135         keepcnt = xprt->timeout->to_retries + 1;
2136         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2137                 (xprt->timeout->to_retries + 1);
2138         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2139         spin_unlock_bh(&xprt->transport_lock);
2140
2141         /* TCP Keepalive options */
2142         kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2143                         (char *)&opt_on, sizeof(opt_on));
2144         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2145                         (char *)&keepidle, sizeof(keepidle));
2146         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2147                         (char *)&keepidle, sizeof(keepidle));
2148         kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2149                         (char *)&keepcnt, sizeof(keepcnt));
2150
2151         /* TCP user timeout (see RFC5482) */
2152         kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2153                         (char *)&timeo, sizeof(timeo));
2154 }
2155
2156 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2157                 unsigned long connect_timeout,
2158                 unsigned long reconnect_timeout)
2159 {
2160         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2161         struct rpc_timeout to;
2162         unsigned long initval;
2163
2164         spin_lock_bh(&xprt->transport_lock);
2165         if (reconnect_timeout < xprt->max_reconnect_timeout)
2166                 xprt->max_reconnect_timeout = reconnect_timeout;
2167         if (connect_timeout < xprt->connect_timeout) {
2168                 memcpy(&to, xprt->timeout, sizeof(to));
2169                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2170                 /* Arbitrary lower limit */
2171                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2172                         initval = XS_TCP_INIT_REEST_TO << 1;
2173                 to.to_initval = initval;
2174                 to.to_maxval = initval;
2175                 memcpy(&transport->tcp_timeout, &to,
2176                                 sizeof(transport->tcp_timeout));
2177                 xprt->timeout = &transport->tcp_timeout;
2178                 xprt->connect_timeout = connect_timeout;
2179         }
2180         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2181         spin_unlock_bh(&xprt->transport_lock);
2182 }
2183
2184 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2185 {
2186         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2187         int ret = -ENOTCONN;
2188
2189         if (!transport->inet) {
2190                 struct sock *sk = sock->sk;
2191                 unsigned int addr_pref = IPV6_PREFER_SRC_PUBLIC;
2192
2193                 /* Avoid temporary address, they are bad for long-lived
2194                  * connections such as NFS mounts.
2195                  * RFC4941, section 3.6 suggests that:
2196                  *    Individual applications, which have specific
2197                  *    knowledge about the normal duration of connections,
2198                  *    MAY override this as appropriate.
2199                  */
2200                 kernel_setsockopt(sock, SOL_IPV6, IPV6_ADDR_PREFERENCES,
2201                                 (char *)&addr_pref, sizeof(addr_pref));
2202
2203                 xs_tcp_set_socket_timeouts(xprt, sock);
2204
2205                 write_lock_bh(&sk->sk_callback_lock);
2206
2207                 xs_save_old_callbacks(transport, sk);
2208
2209                 sk->sk_user_data = xprt;
2210                 sk->sk_data_ready = xs_data_ready;
2211                 sk->sk_state_change = xs_tcp_state_change;
2212                 sk->sk_write_space = xs_tcp_write_space;
2213                 sock_set_flag(sk, SOCK_FASYNC);
2214                 sk->sk_error_report = xs_error_report;
2215                 sk->sk_allocation = GFP_NOIO;
2216
2217                 /* socket options */
2218                 sock_reset_flag(sk, SOCK_LINGER);
2219                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2220
2221                 xprt_clear_connected(xprt);
2222
2223                 /* Reset to new socket */
2224                 transport->sock = sock;
2225                 transport->inet = sk;
2226
2227                 write_unlock_bh(&sk->sk_callback_lock);
2228         }
2229
2230         if (!xprt_bound(xprt))
2231                 goto out;
2232
2233         xs_set_memalloc(xprt);
2234
2235         /* Reset TCP record info */
2236         xs_stream_reset_connect(transport);
2237
2238         /* Tell the socket layer to start connecting... */
2239         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2240         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2241         switch (ret) {
2242         case 0:
2243                 xs_set_srcport(transport, sock);
2244                 /* fall through */
2245         case -EINPROGRESS:
2246                 /* SYN_SENT! */
2247                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2248                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2249                 break;
2250         case -EADDRNOTAVAIL:
2251                 /* Source port number is unavailable. Try a new one! */
2252                 transport->srcport = 0;
2253         }
2254 out:
2255         return ret;
2256 }
2257
2258 /**
2259  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2260  *
2261  * Invoked by a work queue tasklet.
2262  */
2263 static void xs_tcp_setup_socket(struct work_struct *work)
2264 {
2265         struct sock_xprt *transport =
2266                 container_of(work, struct sock_xprt, connect_worker.work);
2267         struct socket *sock = transport->sock;
2268         struct rpc_xprt *xprt = &transport->xprt;
2269         int status = -EIO;
2270
2271         if (!sock) {
2272                 sock = xs_create_sock(xprt, transport,
2273                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2274                                 IPPROTO_TCP, true);
2275                 if (IS_ERR(sock)) {
2276                         status = PTR_ERR(sock);
2277                         goto out;
2278                 }
2279         }
2280
2281         dprintk("RPC:       worker connecting xprt %p via %s to "
2282                                 "%s (port %s)\n", xprt,
2283                         xprt->address_strings[RPC_DISPLAY_PROTO],
2284                         xprt->address_strings[RPC_DISPLAY_ADDR],
2285                         xprt->address_strings[RPC_DISPLAY_PORT]);
2286
2287         status = xs_tcp_finish_connecting(xprt, sock);
2288         trace_rpc_socket_connect(xprt, sock, status);
2289         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2290                         xprt, -status, xprt_connected(xprt),
2291                         sock->sk->sk_state);
2292         switch (status) {
2293         default:
2294                 printk("%s: connect returned unhandled error %d\n",
2295                         __func__, status);
2296                 /* fall through */
2297         case -EADDRNOTAVAIL:
2298                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2299                  * and retry
2300                  */
2301                 xs_tcp_force_close(xprt);
2302                 break;
2303         case 0:
2304         case -EINPROGRESS:
2305         case -EALREADY:
2306                 xprt_unlock_connect(xprt, transport);
2307                 return;
2308         case -EINVAL:
2309                 /* Happens, for instance, if the user specified a link
2310                  * local IPv6 address without a scope-id.
2311                  */
2312         case -ECONNREFUSED:
2313         case -ECONNRESET:
2314         case -ENETDOWN:
2315         case -ENETUNREACH:
2316         case -EHOSTUNREACH:
2317         case -EADDRINUSE:
2318         case -ENOBUFS:
2319                 /*
2320                  * xs_tcp_force_close() wakes tasks with -EIO.
2321                  * We need to wake them first to ensure the
2322                  * correct error code.
2323                  */
2324                 xprt_wake_pending_tasks(xprt, status);
2325                 xs_tcp_force_close(xprt);
2326                 goto out;
2327         }
2328         status = -EAGAIN;
2329 out:
2330         xprt_clear_connecting(xprt);
2331         xprt_unlock_connect(xprt, transport);
2332         xprt_wake_pending_tasks(xprt, status);
2333 }
2334
2335 static unsigned long xs_reconnect_delay(const struct rpc_xprt *xprt)
2336 {
2337         unsigned long start, now = jiffies;
2338
2339         start = xprt->stat.connect_start + xprt->reestablish_timeout;
2340         if (time_after(start, now))
2341                 return start - now;
2342         return 0;
2343 }
2344
2345 static void xs_reconnect_backoff(struct rpc_xprt *xprt)
2346 {
2347         xprt->reestablish_timeout <<= 1;
2348         if (xprt->reestablish_timeout > xprt->max_reconnect_timeout)
2349                 xprt->reestablish_timeout = xprt->max_reconnect_timeout;
2350         if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2351                 xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2352 }
2353
2354 /**
2355  * xs_connect - connect a socket to a remote endpoint
2356  * @xprt: pointer to transport structure
2357  * @task: address of RPC task that manages state of connect request
2358  *
2359  * TCP: If the remote end dropped the connection, delay reconnecting.
2360  *
2361  * UDP socket connects are synchronous, but we use a work queue anyway
2362  * to guarantee that even unprivileged user processes can set up a
2363  * socket on a privileged port.
2364  *
2365  * If a UDP socket connect fails, the delay behavior here prevents
2366  * retry floods (hard mounts).
2367  */
2368 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2369 {
2370         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2371         unsigned long delay = 0;
2372
2373         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2374
2375         if (transport->sock != NULL) {
2376                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2377                                 "seconds\n",
2378                                 xprt, xprt->reestablish_timeout / HZ);
2379
2380                 /* Start by resetting any existing state */
2381                 xs_reset_transport(transport);
2382
2383                 delay = xs_reconnect_delay(xprt);
2384                 xs_reconnect_backoff(xprt);
2385
2386         } else
2387                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2388
2389         queue_delayed_work(xprtiod_workqueue,
2390                         &transport->connect_worker,
2391                         delay);
2392 }
2393
2394 /**
2395  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2396  * @xprt: rpc_xprt struct containing statistics
2397  * @seq: output file
2398  *
2399  */
2400 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2401 {
2402         long idle_time = 0;
2403
2404         if (xprt_connected(xprt))
2405                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2406
2407         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2408                         "%llu %llu %lu %llu %llu\n",
2409                         xprt->stat.bind_count,
2410                         xprt->stat.connect_count,
2411                         xprt->stat.connect_time / HZ,
2412                         idle_time,
2413                         xprt->stat.sends,
2414                         xprt->stat.recvs,
2415                         xprt->stat.bad_xids,
2416                         xprt->stat.req_u,
2417                         xprt->stat.bklog_u,
2418                         xprt->stat.max_slots,
2419                         xprt->stat.sending_u,
2420                         xprt->stat.pending_u);
2421 }
2422
2423 /**
2424  * xs_udp_print_stats - display UDP socket-specifc stats
2425  * @xprt: rpc_xprt struct containing statistics
2426  * @seq: output file
2427  *
2428  */
2429 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2430 {
2431         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2432
2433         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2434                         "%lu %llu %llu\n",
2435                         transport->srcport,
2436                         xprt->stat.bind_count,
2437                         xprt->stat.sends,
2438                         xprt->stat.recvs,
2439                         xprt->stat.bad_xids,
2440                         xprt->stat.req_u,
2441                         xprt->stat.bklog_u,
2442                         xprt->stat.max_slots,
2443                         xprt->stat.sending_u,
2444                         xprt->stat.pending_u);
2445 }
2446
2447 /**
2448  * xs_tcp_print_stats - display TCP socket-specifc stats
2449  * @xprt: rpc_xprt struct containing statistics
2450  * @seq: output file
2451  *
2452  */
2453 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2454 {
2455         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2456         long idle_time = 0;
2457
2458         if (xprt_connected(xprt))
2459                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2460
2461         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2462                         "%llu %llu %lu %llu %llu\n",
2463                         transport->srcport,
2464                         xprt->stat.bind_count,
2465                         xprt->stat.connect_count,
2466                         xprt->stat.connect_time / HZ,
2467                         idle_time,
2468                         xprt->stat.sends,
2469                         xprt->stat.recvs,
2470                         xprt->stat.bad_xids,
2471                         xprt->stat.req_u,
2472                         xprt->stat.bklog_u,
2473                         xprt->stat.max_slots,
2474                         xprt->stat.sending_u,
2475                         xprt->stat.pending_u);
2476 }
2477
2478 /*
2479  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2480  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2481  * to use the server side send routines.
2482  */
2483 static int bc_malloc(struct rpc_task *task)
2484 {
2485         struct rpc_rqst *rqst = task->tk_rqstp;
2486         size_t size = rqst->rq_callsize;
2487         struct page *page;
2488         struct rpc_buffer *buf;
2489
2490         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2491                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2492                           size);
2493                 return -EINVAL;
2494         }
2495
2496         page = alloc_page(GFP_KERNEL);
2497         if (!page)
2498                 return -ENOMEM;
2499
2500         buf = page_address(page);
2501         buf->len = PAGE_SIZE;
2502
2503         rqst->rq_buffer = buf->data;
2504         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2505         return 0;
2506 }
2507
2508 /*
2509  * Free the space allocated in the bc_alloc routine
2510  */
2511 static void bc_free(struct rpc_task *task)
2512 {
2513         void *buffer = task->tk_rqstp->rq_buffer;
2514         struct rpc_buffer *buf;
2515
2516         buf = container_of(buffer, struct rpc_buffer, data);
2517         free_page((unsigned long)buf);
2518 }
2519
2520 /*
2521  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2522  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2523  */
2524 static int bc_sendto(struct rpc_rqst *req)
2525 {
2526         int len;
2527         struct xdr_buf *xbufp = &req->rq_snd_buf;
2528         struct rpc_xprt *xprt = req->rq_xprt;
2529         struct sock_xprt *transport =
2530                                 container_of(xprt, struct sock_xprt, xprt);
2531         struct socket *sock = transport->sock;
2532         unsigned long headoff;
2533         unsigned long tailoff;
2534
2535         xs_encode_stream_record_marker(xbufp);
2536
2537         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2538         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2539         len = svc_send_common(sock, xbufp,
2540                               virt_to_page(xbufp->head[0].iov_base), headoff,
2541                               xbufp->tail[0].iov_base, tailoff);
2542
2543         if (len != xbufp->len) {
2544                 printk(KERN_NOTICE "Error sending entire callback!\n");
2545                 len = -EAGAIN;
2546         }
2547
2548         return len;
2549 }
2550
2551 /*
2552  * The send routine. Borrows from svc_send
2553  */
2554 static int bc_send_request(struct rpc_rqst *req)
2555 {
2556         struct svc_xprt *xprt;
2557         int len;
2558
2559         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2560         /*
2561          * Get the server socket associated with this callback xprt
2562          */
2563         xprt = req->rq_xprt->bc_xprt;
2564
2565         /*
2566          * Grab the mutex to serialize data as the connection is shared
2567          * with the fore channel
2568          */
2569         mutex_lock(&xprt->xpt_mutex);
2570         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2571                 len = -ENOTCONN;
2572         else
2573                 len = bc_sendto(req);
2574         mutex_unlock(&xprt->xpt_mutex);
2575
2576         if (len > 0)
2577                 len = 0;
2578
2579         return len;
2580 }
2581
2582 /*
2583  * The close routine. Since this is client initiated, we do nothing
2584  */
2585
2586 static void bc_close(struct rpc_xprt *xprt)
2587 {
2588 }
2589
2590 /*
2591  * The xprt destroy routine. Again, because this connection is client
2592  * initiated, we do nothing
2593  */
2594
2595 static void bc_destroy(struct rpc_xprt *xprt)
2596 {
2597         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2598
2599         xs_xprt_free(xprt);
2600         module_put(THIS_MODULE);
2601 }
2602
2603 static const struct rpc_xprt_ops xs_local_ops = {
2604         .reserve_xprt           = xprt_reserve_xprt,
2605         .release_xprt           = xprt_release_xprt,
2606         .alloc_slot             = xprt_alloc_slot,
2607         .free_slot              = xprt_free_slot,
2608         .rpcbind                = xs_local_rpcbind,
2609         .set_port               = xs_local_set_port,
2610         .connect                = xs_local_connect,
2611         .buf_alloc              = rpc_malloc,
2612         .buf_free               = rpc_free,
2613         .prepare_request        = xs_stream_prepare_request,
2614         .send_request           = xs_local_send_request,
2615         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2616         .close                  = xs_close,
2617         .destroy                = xs_destroy,
2618         .print_stats            = xs_local_print_stats,
2619         .enable_swap            = xs_enable_swap,
2620         .disable_swap           = xs_disable_swap,
2621 };
2622
2623 static const struct rpc_xprt_ops xs_udp_ops = {
2624         .set_buffer_size        = xs_udp_set_buffer_size,
2625         .reserve_xprt           = xprt_reserve_xprt_cong,
2626         .release_xprt           = xprt_release_xprt_cong,
2627         .alloc_slot             = xprt_alloc_slot,
2628         .free_slot              = xprt_free_slot,
2629         .rpcbind                = rpcb_getport_async,
2630         .set_port               = xs_set_port,
2631         .connect                = xs_connect,
2632         .buf_alloc              = rpc_malloc,
2633         .buf_free               = rpc_free,
2634         .send_request           = xs_udp_send_request,
2635         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2636         .timer                  = xs_udp_timer,
2637         .release_request        = xprt_release_rqst_cong,
2638         .close                  = xs_close,
2639         .destroy                = xs_destroy,
2640         .print_stats            = xs_udp_print_stats,
2641         .enable_swap            = xs_enable_swap,
2642         .disable_swap           = xs_disable_swap,
2643         .inject_disconnect      = xs_inject_disconnect,
2644 };
2645
2646 static const struct rpc_xprt_ops xs_tcp_ops = {
2647         .reserve_xprt           = xprt_reserve_xprt,
2648         .release_xprt           = xprt_release_xprt,
2649         .alloc_slot             = xprt_alloc_slot,
2650         .free_slot              = xprt_free_slot,
2651         .rpcbind                = rpcb_getport_async,
2652         .set_port               = xs_set_port,
2653         .connect                = xs_connect,
2654         .buf_alloc              = rpc_malloc,
2655         .buf_free               = rpc_free,
2656         .prepare_request        = xs_stream_prepare_request,
2657         .send_request           = xs_tcp_send_request,
2658         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2659         .close                  = xs_tcp_shutdown,
2660         .destroy                = xs_destroy,
2661         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2662         .print_stats            = xs_tcp_print_stats,
2663         .enable_swap            = xs_enable_swap,
2664         .disable_swap           = xs_disable_swap,
2665         .inject_disconnect      = xs_inject_disconnect,
2666 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2667         .bc_setup               = xprt_setup_bc,
2668         .bc_up                  = xs_tcp_bc_up,
2669         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2670         .bc_free_rqst           = xprt_free_bc_rqst,
2671         .bc_destroy             = xprt_destroy_bc,
2672 #endif
2673 };
2674
2675 /*
2676  * The rpc_xprt_ops for the server backchannel
2677  */
2678
2679 static const struct rpc_xprt_ops bc_tcp_ops = {
2680         .reserve_xprt           = xprt_reserve_xprt,
2681         .release_xprt           = xprt_release_xprt,
2682         .alloc_slot             = xprt_alloc_slot,
2683         .free_slot              = xprt_free_slot,
2684         .buf_alloc              = bc_malloc,
2685         .buf_free               = bc_free,
2686         .send_request           = bc_send_request,
2687         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2688         .close                  = bc_close,
2689         .destroy                = bc_destroy,
2690         .print_stats            = xs_tcp_print_stats,
2691         .enable_swap            = xs_enable_swap,
2692         .disable_swap           = xs_disable_swap,
2693         .inject_disconnect      = xs_inject_disconnect,
2694 };
2695
2696 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2697 {
2698         static const struct sockaddr_in sin = {
2699                 .sin_family             = AF_INET,
2700                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2701         };
2702         static const struct sockaddr_in6 sin6 = {
2703                 .sin6_family            = AF_INET6,
2704                 .sin6_addr              = IN6ADDR_ANY_INIT,
2705         };
2706
2707         switch (family) {
2708         case AF_LOCAL:
2709                 break;
2710         case AF_INET:
2711                 memcpy(sap, &sin, sizeof(sin));
2712                 break;
2713         case AF_INET6:
2714                 memcpy(sap, &sin6, sizeof(sin6));
2715                 break;
2716         default:
2717                 dprintk("RPC:       %s: Bad address family\n", __func__);
2718                 return -EAFNOSUPPORT;
2719         }
2720         return 0;
2721 }
2722
2723 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2724                                       unsigned int slot_table_size,
2725                                       unsigned int max_slot_table_size)
2726 {
2727         struct rpc_xprt *xprt;
2728         struct sock_xprt *new;
2729
2730         if (args->addrlen > sizeof(xprt->addr)) {
2731                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2732                 return ERR_PTR(-EBADF);
2733         }
2734
2735         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2736                         max_slot_table_size);
2737         if (xprt == NULL) {
2738                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2739                                 "rpc_xprt\n");
2740                 return ERR_PTR(-ENOMEM);
2741         }
2742
2743         new = container_of(xprt, struct sock_xprt, xprt);
2744         mutex_init(&new->recv_mutex);
2745         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2746         xprt->addrlen = args->addrlen;
2747         if (args->srcaddr)
2748                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2749         else {
2750                 int err;
2751                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2752                                         (struct sockaddr *)&new->srcaddr);
2753                 if (err != 0) {
2754                         xprt_free(xprt);
2755                         return ERR_PTR(err);
2756                 }
2757         }
2758
2759         return xprt;
2760 }
2761
2762 static const struct rpc_timeout xs_local_default_timeout = {
2763         .to_initval = 10 * HZ,
2764         .to_maxval = 10 * HZ,
2765         .to_retries = 2,
2766 };
2767
2768 /**
2769  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2770  * @args: rpc transport creation arguments
2771  *
2772  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2773  */
2774 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2775 {
2776         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2777         struct sock_xprt *transport;
2778         struct rpc_xprt *xprt;
2779         struct rpc_xprt *ret;
2780
2781         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2782                         xprt_max_tcp_slot_table_entries);
2783         if (IS_ERR(xprt))
2784                 return xprt;
2785         transport = container_of(xprt, struct sock_xprt, xprt);
2786
2787         xprt->prot = 0;
2788         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2789         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2790
2791         xprt->bind_timeout = XS_BIND_TO;
2792         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2793         xprt->idle_timeout = XS_IDLE_DISC_TO;
2794
2795         xprt->ops = &xs_local_ops;
2796         xprt->timeout = &xs_local_default_timeout;
2797
2798         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2799         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2800
2801         switch (sun->sun_family) {
2802         case AF_LOCAL:
2803                 if (sun->sun_path[0] != '/') {
2804                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2805                                         sun->sun_path);
2806                         ret = ERR_PTR(-EINVAL);
2807                         goto out_err;
2808                 }
2809                 xprt_set_bound(xprt);
2810                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2811                 ret = ERR_PTR(xs_local_setup_socket(transport));
2812                 if (ret)
2813                         goto out_err;
2814                 break;
2815         default:
2816                 ret = ERR_PTR(-EAFNOSUPPORT);
2817                 goto out_err;
2818         }
2819
2820         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2821                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2822
2823         if (try_module_get(THIS_MODULE))
2824                 return xprt;
2825         ret = ERR_PTR(-EINVAL);
2826 out_err:
2827         xs_xprt_free(xprt);
2828         return ret;
2829 }
2830
2831 static const struct rpc_timeout xs_udp_default_timeout = {
2832         .to_initval = 5 * HZ,
2833         .to_maxval = 30 * HZ,
2834         .to_increment = 5 * HZ,
2835         .to_retries = 5,
2836 };
2837
2838 /**
2839  * xs_setup_udp - Set up transport to use a UDP socket
2840  * @args: rpc transport creation arguments
2841  *
2842  */
2843 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2844 {
2845         struct sockaddr *addr = args->dstaddr;
2846         struct rpc_xprt *xprt;
2847         struct sock_xprt *transport;
2848         struct rpc_xprt *ret;
2849
2850         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2851                         xprt_udp_slot_table_entries);
2852         if (IS_ERR(xprt))
2853                 return xprt;
2854         transport = container_of(xprt, struct sock_xprt, xprt);
2855
2856         xprt->prot = IPPROTO_UDP;
2857         xprt->tsh_size = 0;
2858         /* XXX: header size can vary due to auth type, IPv6, etc. */
2859         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2860
2861         xprt->bind_timeout = XS_BIND_TO;
2862         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2863         xprt->idle_timeout = XS_IDLE_DISC_TO;
2864
2865         xprt->ops = &xs_udp_ops;
2866
2867         xprt->timeout = &xs_udp_default_timeout;
2868
2869         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2870         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2871
2872         switch (addr->sa_family) {
2873         case AF_INET:
2874                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2875                         xprt_set_bound(xprt);
2876
2877                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2878                 break;
2879         case AF_INET6:
2880                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2881                         xprt_set_bound(xprt);
2882
2883                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2884                 break;
2885         default:
2886                 ret = ERR_PTR(-EAFNOSUPPORT);
2887                 goto out_err;
2888         }
2889
2890         if (xprt_bound(xprt))
2891                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2892                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2893                                 xprt->address_strings[RPC_DISPLAY_PORT],
2894                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2895         else
2896                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2897                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2898                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2899
2900         if (try_module_get(THIS_MODULE))
2901                 return xprt;
2902         ret = ERR_PTR(-EINVAL);
2903 out_err:
2904         xs_xprt_free(xprt);
2905         return ret;
2906 }
2907
2908 static const struct rpc_timeout xs_tcp_default_timeout = {
2909         .to_initval = 60 * HZ,
2910         .to_maxval = 60 * HZ,
2911         .to_retries = 2,
2912 };
2913
2914 /**
2915  * xs_setup_tcp - Set up transport to use a TCP socket
2916  * @args: rpc transport creation arguments
2917  *
2918  */
2919 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2920 {
2921         struct sockaddr *addr = args->dstaddr;
2922         struct rpc_xprt *xprt;
2923         struct sock_xprt *transport;
2924         struct rpc_xprt *ret;
2925         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2926
2927         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2928                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2929
2930         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2931                         max_slot_table_size);
2932         if (IS_ERR(xprt))
2933                 return xprt;
2934         transport = container_of(xprt, struct sock_xprt, xprt);
2935
2936         xprt->prot = IPPROTO_TCP;
2937         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2938         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2939
2940         xprt->bind_timeout = XS_BIND_TO;
2941         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2942         xprt->idle_timeout = XS_IDLE_DISC_TO;
2943
2944         xprt->ops = &xs_tcp_ops;
2945         xprt->timeout = &xs_tcp_default_timeout;
2946
2947         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2948         xprt->connect_timeout = xprt->timeout->to_initval *
2949                 (xprt->timeout->to_retries + 1);
2950
2951         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2952         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2953
2954         switch (addr->sa_family) {
2955         case AF_INET:
2956                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2957                         xprt_set_bound(xprt);
2958
2959                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2960                 break;
2961         case AF_INET6:
2962                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2963                         xprt_set_bound(xprt);
2964
2965                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2966                 break;
2967         default:
2968                 ret = ERR_PTR(-EAFNOSUPPORT);
2969                 goto out_err;
2970         }
2971
2972         if (xprt_bound(xprt))
2973                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2974                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2975                                 xprt->address_strings[RPC_DISPLAY_PORT],
2976                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2977         else
2978                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2979                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2980                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2981
2982         if (try_module_get(THIS_MODULE))
2983                 return xprt;
2984         ret = ERR_PTR(-EINVAL);
2985 out_err:
2986         xs_xprt_free(xprt);
2987         return ret;
2988 }
2989
2990 /**
2991  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2992  * @args: rpc transport creation arguments
2993  *
2994  */
2995 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2996 {
2997         struct sockaddr *addr = args->dstaddr;
2998         struct rpc_xprt *xprt;
2999         struct sock_xprt *transport;
3000         struct svc_sock *bc_sock;
3001         struct rpc_xprt *ret;
3002
3003         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3004                         xprt_tcp_slot_table_entries);
3005         if (IS_ERR(xprt))
3006                 return xprt;
3007         transport = container_of(xprt, struct sock_xprt, xprt);
3008
3009         xprt->prot = IPPROTO_TCP;
3010         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
3011         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3012         xprt->timeout = &xs_tcp_default_timeout;
3013
3014         /* backchannel */
3015         xprt_set_bound(xprt);
3016         xprt->bind_timeout = 0;
3017         xprt->reestablish_timeout = 0;
3018         xprt->idle_timeout = 0;
3019
3020         xprt->ops = &bc_tcp_ops;
3021
3022         switch (addr->sa_family) {
3023         case AF_INET:
3024                 xs_format_peer_addresses(xprt, "tcp",
3025                                          RPCBIND_NETID_TCP);
3026                 break;
3027         case AF_INET6:
3028                 xs_format_peer_addresses(xprt, "tcp",
3029                                    RPCBIND_NETID_TCP6);
3030                 break;
3031         default:
3032                 ret = ERR_PTR(-EAFNOSUPPORT);
3033                 goto out_err;
3034         }
3035
3036         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3037                         xprt->address_strings[RPC_DISPLAY_ADDR],
3038                         xprt->address_strings[RPC_DISPLAY_PORT],
3039                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3040
3041         /*
3042          * Once we've associated a backchannel xprt with a connection,
3043          * we want to keep it around as long as the connection lasts,
3044          * in case we need to start using it for a backchannel again;
3045          * this reference won't be dropped until bc_xprt is destroyed.
3046          */
3047         xprt_get(xprt);
3048         args->bc_xprt->xpt_bc_xprt = xprt;
3049         xprt->bc_xprt = args->bc_xprt;
3050         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3051         transport->sock = bc_sock->sk_sock;
3052         transport->inet = bc_sock->sk_sk;
3053
3054         /*
3055          * Since we don't want connections for the backchannel, we set
3056          * the xprt status to connected
3057          */
3058         xprt_set_connected(xprt);
3059
3060         if (try_module_get(THIS_MODULE))
3061                 return xprt;
3062
3063         args->bc_xprt->xpt_bc_xprt = NULL;
3064         args->bc_xprt->xpt_bc_xps = NULL;
3065         xprt_put(xprt);
3066         ret = ERR_PTR(-EINVAL);
3067 out_err:
3068         xs_xprt_free(xprt);
3069         return ret;
3070 }
3071
3072 static struct xprt_class        xs_local_transport = {
3073         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3074         .name           = "named UNIX socket",
3075         .owner          = THIS_MODULE,
3076         .ident          = XPRT_TRANSPORT_LOCAL,
3077         .setup          = xs_setup_local,
3078 };
3079
3080 static struct xprt_class        xs_udp_transport = {
3081         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3082         .name           = "udp",
3083         .owner          = THIS_MODULE,
3084         .ident          = XPRT_TRANSPORT_UDP,
3085         .setup          = xs_setup_udp,
3086 };
3087
3088 static struct xprt_class        xs_tcp_transport = {
3089         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3090         .name           = "tcp",
3091         .owner          = THIS_MODULE,
3092         .ident          = XPRT_TRANSPORT_TCP,
3093         .setup          = xs_setup_tcp,
3094 };
3095
3096 static struct xprt_class        xs_bc_tcp_transport = {
3097         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3098         .name           = "tcp NFSv4.1 backchannel",
3099         .owner          = THIS_MODULE,
3100         .ident          = XPRT_TRANSPORT_BC_TCP,
3101         .setup          = xs_setup_bc_tcp,
3102 };
3103
3104 /**
3105  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3106  *
3107  */
3108 int init_socket_xprt(void)
3109 {
3110 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3111         if (!sunrpc_table_header)
3112                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3113 #endif
3114
3115         xprt_register_transport(&xs_local_transport);
3116         xprt_register_transport(&xs_udp_transport);
3117         xprt_register_transport(&xs_tcp_transport);
3118         xprt_register_transport(&xs_bc_tcp_transport);
3119
3120         return 0;
3121 }
3122
3123 /**
3124  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3125  *
3126  */
3127 void cleanup_socket_xprt(void)
3128 {
3129 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3130         if (sunrpc_table_header) {
3131                 unregister_sysctl_table(sunrpc_table_header);
3132                 sunrpc_table_header = NULL;
3133         }
3134 #endif
3135
3136         xprt_unregister_transport(&xs_local_transport);
3137         xprt_unregister_transport(&xs_udp_transport);
3138         xprt_unregister_transport(&xs_tcp_transport);
3139         xprt_unregister_transport(&xs_bc_tcp_transport);
3140 }
3141
3142 static int param_set_uint_minmax(const char *val,
3143                 const struct kernel_param *kp,
3144                 unsigned int min, unsigned int max)
3145 {
3146         unsigned int num;
3147         int ret;
3148
3149         if (!val)
3150                 return -EINVAL;
3151         ret = kstrtouint(val, 0, &num);
3152         if (ret)
3153                 return ret;
3154         if (num < min || num > max)
3155                 return -EINVAL;
3156         *((unsigned int *)kp->arg) = num;
3157         return 0;
3158 }
3159
3160 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3161 {
3162         return param_set_uint_minmax(val, kp,
3163                         RPC_MIN_RESVPORT,
3164                         RPC_MAX_RESVPORT);
3165 }
3166
3167 static const struct kernel_param_ops param_ops_portnr = {
3168         .set = param_set_portnr,
3169         .get = param_get_uint,
3170 };
3171
3172 #define param_check_portnr(name, p) \
3173         __param_check(name, p, unsigned int);
3174
3175 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3176 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3177
3178 static int param_set_slot_table_size(const char *val,
3179                                      const struct kernel_param *kp)
3180 {
3181         return param_set_uint_minmax(val, kp,
3182                         RPC_MIN_SLOT_TABLE,
3183                         RPC_MAX_SLOT_TABLE);
3184 }
3185
3186 static const struct kernel_param_ops param_ops_slot_table_size = {
3187         .set = param_set_slot_table_size,
3188         .get = param_get_uint,
3189 };
3190
3191 #define param_check_slot_table_size(name, p) \
3192         __param_check(name, p, unsigned int);
3193
3194 static int param_set_max_slot_table_size(const char *val,
3195                                      const struct kernel_param *kp)
3196 {
3197         return param_set_uint_minmax(val, kp,
3198                         RPC_MIN_SLOT_TABLE,
3199                         RPC_MAX_SLOT_TABLE_LIMIT);
3200 }
3201
3202 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3203         .set = param_set_max_slot_table_size,
3204         .get = param_get_uint,
3205 };
3206
3207 #define param_check_max_slot_table_size(name, p) \
3208         __param_check(name, p, unsigned int);
3209
3210 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3211                    slot_table_size, 0644);
3212 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3213                    max_slot_table_size, 0644);
3214 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3215                    slot_table_size, 0644);