net/sunrpc/xprtsock.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/net/sunrpc/xprtsock.c
   4  *
   5  * Client-side transport implementation for sockets.
   6  *
   7  * TCP callback races fixes (C) 1998 Red Hat
   8  * TCP send fixes (C) 1998 Red Hat
   9  * TCP NFS related read + write fixes
  10  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  11  *
  12  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  13  * Fix behaviour when socket buffer is full.
  14  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  15  *
  16  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  17  *
  18  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  19  *   <gilles.quillard@bull.net>
  20  */
  21
  22 #include <linux/types.h>
  23 #include <linux/string.h>
  24 #include <linux/slab.h>
  25 #include <linux/module.h>
  26 #include <linux/capability.h>
  27 #include <linux/pagemap.h>
  28 #include <linux/errno.h>
  29 #include <linux/socket.h>
  30 #include <linux/in.h>
  31 #include <linux/net.h>
  32 #include <linux/mm.h>
  33 #include <linux/un.h>
  34 #include <linux/udp.h>
  35 #include <linux/tcp.h>
  36 #include <linux/sunrpc/clnt.h>
  37 #include <linux/sunrpc/addr.h>
  38 #include <linux/sunrpc/sched.h>
  39 #include <linux/sunrpc/svcsock.h>
  40 #include <linux/sunrpc/xprtsock.h>
  41 #include <linux/file.h>
  42 #ifdef CONFIG_SUNRPC_BACKCHANNEL
  43 #include <linux/sunrpc/bc_xprt.h>
  44 #endif
  45
  46 #include <net/sock.h>
  47 #include <net/checksum.h>
  48 #include <net/udp.h>
  49 #include <net/tcp.h>
  50 #include <linux/bvec.h>
  51 #include <linux/highmem.h>
  52 #include <linux/uio.h>
  53 #include <linux/sched/mm.h>
  54
  55 #include <trace/events/sunrpc.h>
  56
  57 #include "socklib.h"
  58 #include "sunrpc.h"
  59
  60 static void xs_close(struct rpc_xprt *xprt);
  61 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
  62                 struct socket *sock);
  63
  64 /*
  65  * xprtsock tunables
  66  */
  67 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  68 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  69 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  70
  71 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  72 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  73
  74 #define XS_TCP_LINGER_TO        (15U * HZ)
  75 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  76
  77 /*
  78  * We can register our own files under /proc/sys/sunrpc by
  79  * calling register_sysctl_table() again.  The files in that
  80  * directory become the union of all files registered there.
  81  *
  82  * We simply need to make sure that we don't collide with
  83  * someone else's file names!
  84  */
  85
  86 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  87 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  88 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  89 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  90 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  91
  92 static struct ctl_table_header *sunrpc_table_header;
  93
  94 static struct xprt_class xs_local_transport;
  95 static struct xprt_class xs_udp_transport;
  96 static struct xprt_class xs_tcp_transport;
  97 static struct xprt_class xs_bc_tcp_transport;
  98
  99 /*
 100  * FIXME: changing the UDP slot table size should also resize the UDP
 101  *        socket buffers for existing UDP transports
 102  */
 103 static struct ctl_table xs_tunables_table[] = {
 104         {
 105                 .procname       = "udp_slot_table_entries",
 106                 .data           = &xprt_udp_slot_table_entries,
 107                 .maxlen         = sizeof(unsigned int),
 108                 .mode           = 0644,
 109                 .proc_handler   = proc_dointvec_minmax,
 110                 .extra1         = &min_slot_table_size,
 111                 .extra2         = &max_slot_table_size
 112         },
 113         {
 114                 .procname       = "tcp_slot_table_entries",
 115                 .data           = &xprt_tcp_slot_table_entries,
 116                 .maxlen         = sizeof(unsigned int),
 117                 .mode           = 0644,
 118                 .proc_handler   = proc_dointvec_minmax,
 119                 .extra1         = &min_slot_table_size,
 120                 .extra2         = &max_slot_table_size
 121         },
 122         {
 123                 .procname       = "tcp_max_slot_table_entries",
 124                 .data           = &xprt_max_tcp_slot_table_entries,
 125                 .maxlen         = sizeof(unsigned int),
 126                 .mode           = 0644,
 127                 .proc_handler   = proc_dointvec_minmax,
 128                 .extra1         = &min_slot_table_size,
 129                 .extra2         = &max_tcp_slot_table_limit
 130         },
 131         {
 132                 .procname       = "min_resvport",
 133                 .data           = &xprt_min_resvport,
 134                 .maxlen         = sizeof(unsigned int),
 135                 .mode           = 0644,
 136                 .proc_handler   = proc_dointvec_minmax,
 137                 .extra1         = &xprt_min_resvport_limit,
 138                 .extra2         = &xprt_max_resvport_limit
 139         },
 140         {
 141                 .procname       = "max_resvport",
 142                 .data           = &xprt_max_resvport,
 143                 .maxlen         = sizeof(unsigned int),
 144                 .mode           = 0644,
 145                 .proc_handler   = proc_dointvec_minmax,
 146                 .extra1         = &xprt_min_resvport_limit,
 147                 .extra2         = &xprt_max_resvport_limit
 148         },
 149         {
 150                 .procname       = "tcp_fin_timeout",
 151                 .data           = &xs_tcp_fin_timeout,
 152                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 153                 .mode           = 0644,
 154                 .proc_handler   = proc_dointvec_jiffies,
 155         },
 156         { },
 157 };
 158
 159 static struct ctl_table sunrpc_table[] = {
 160         {
 161                 .procname       = "sunrpc",
 162                 .mode           = 0555,
 163                 .child          = xs_tunables_table
 164         },
 165         { },
 166 };
 167
 168 /*
 169  * Wait duration for a reply from the RPC portmapper.
 170  */
 171 #define XS_BIND_TO              (60U * HZ)
 172
 173 /*
 174  * Delay if a UDP socket connect error occurs.  This is most likely some
 175  * kind of resource problem on the local host.
 176  */
 177 #define XS_UDP_REEST_TO         (2U * HZ)
 178
 179 /*
 180  * The reestablish timeout allows clients to delay for a bit before attempting
 181  * to reconnect to a server that just dropped our connection.
 182  *
 183  * We implement an exponential backoff when trying to reestablish a TCP
 184  * transport connection with the server.  Some servers like to drop a TCP
 185  * connection when they are overworked, so we start with a short timeout and
 186  * increase over time if the server is down or not responding.
 187  */
 188 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 189
 190 /*
 191  * TCP idle timeout; client drops the transport socket if it is idle
 192  * for this long.  Note that we also timeout UDP sockets to prevent
 193  * holding port numbers when there is no RPC traffic.
 194  */
 195 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 196
 197 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 198 # undef  RPC_DEBUG_DATA
 199 # define RPCDBG_FACILITY        RPCDBG_TRANS
 200 #endif
 201
 202 #ifdef RPC_DEBUG_DATA
 203 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 204 {
 205         u8 *buf = (u8 *) packet;
 206         int j;
 207
 208         dprintk("RPC:       %s\n", msg);
 209         for (j = 0; j < count && j < 128; j += 4) {
 210                 if (!(j & 31)) {
 211                         if (j)
 212                                 dprintk("\n");
 213                         dprintk("0x%04x ", j);
 214                 }
 215                 dprintk("%02x%02x%02x%02x ",
 216                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 217         }
 218         dprintk("\n");
 219 }
 220 #else
 221 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 222 {
 223         /* NOP */
 224 }
 225 #endif
 226
 227 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 228 {
 229         return (struct rpc_xprt *) sk->sk_user_data;
 230 }
 231
 232 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 233 {
 234         return (struct sockaddr *) &xprt->addr;
 235 }
 236
 237 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 238 {
 239         return (struct sockaddr_un *) &xprt->addr;
 240 }
 241
 242 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 243 {
 244         return (struct sockaddr_in *) &xprt->addr;
 245 }
 246
 247 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 248 {
 249         return (struct sockaddr_in6 *) &xprt->addr;
 250 }
 251
 252 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 253 {
 254         struct sockaddr *sap = xs_addr(xprt);
 255         struct sockaddr_in6 *sin6;
 256         struct sockaddr_in *sin;
 257         struct sockaddr_un *sun;
 258         char buf[128];
 259
 260         switch (sap->sa_family) {
 261         case AF_LOCAL:
 262                 sun = xs_addr_un(xprt);
 263                 strlcpy(buf, sun->sun_path, sizeof(buf));
 264                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 265                                                 kstrdup(buf, GFP_KERNEL);
 266                 break;
 267         case AF_INET:
 268                 (void)rpc_ntop(sap, buf, sizeof(buf));
 269                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 270                                                 kstrdup(buf, GFP_KERNEL);
 271                 sin = xs_addr_in(xprt);
 272                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 273                 break;
 274         case AF_INET6:
 275                 (void)rpc_ntop(sap, buf, sizeof(buf));
 276                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 277                                                 kstrdup(buf, GFP_KERNEL);
 278                 sin6 = xs_addr_in6(xprt);
 279                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 280                 break;
 281         default:
 282                 BUG();
 283         }
 284
 285         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 286 }
 287
 288 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 289 {
 290         struct sockaddr *sap = xs_addr(xprt);
 291         char buf[128];
 292
 293         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 294         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 295
 296         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 297         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 298 }
 299
 300 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 301                                      const char *protocol,
 302                                      const char *netid)
 303 {
 304         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 305         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 306         xs_format_common_peer_addresses(xprt);
 307         xs_format_common_peer_ports(xprt);
 308 }
 309
 310 static void xs_update_peer_port(struct rpc_xprt *xprt)
 311 {
 312         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 313         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 314
 315         xs_format_common_peer_ports(xprt);
 316 }
 317
 318 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 319 {
 320         unsigned int i;
 321
 322         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 323                 switch (i) {
 324                 case RPC_DISPLAY_PROTO:
 325                 case RPC_DISPLAY_NETID:
 326                         continue;
 327                 default:
 328                         kfree(xprt->address_strings[i]);
 329                 }
 330 }
 331
 332 static size_t
 333 xs_alloc_sparse_pages(struct xdr_buf *buf, size_t want, gfp_t gfp)
 334 {
 335         size_t i,n;
 336
 337         if (!want || !(buf->flags & XDRBUF_SPARSE_PAGES))
 338                 return want;
 339         n = (buf->page_base + want + PAGE_SIZE - 1) >> PAGE_SHIFT;
 340         for (i = 0; i < n; i++) {
 341                 if (buf->pages[i])
 342                         continue;
 343                 buf->bvec[i].bv_page = buf->pages[i] = alloc_page(gfp);
 344                 if (!buf->pages[i]) {
 345                         i *= PAGE_SIZE;
 346                         return i > buf->page_base ? i - buf->page_base : 0;
 347                 }
 348         }
 349         return want;
 350 }
 351
 352 static ssize_t
 353 xs_sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags, size_t seek)
 354 {
 355         ssize_t ret;
 356         if (seek != 0)
 357                 iov_iter_advance(&msg->msg_iter, seek);
 358         ret = sock_recvmsg(sock, msg, flags);
 359         return ret > 0 ? ret + seek : ret;
 360 }
 361
 362 static ssize_t
 363 xs_read_kvec(struct socket *sock, struct msghdr *msg, int flags,
 364                 struct kvec *kvec, size_t count, size_t seek)
 365 {
 366         iov_iter_kvec(&msg->msg_iter, READ, kvec, 1, count);
 367         return xs_sock_recvmsg(sock, msg, flags, seek);
 368 }
 369
 370 static ssize_t
 371 xs_read_bvec(struct socket *sock, struct msghdr *msg, int flags,
 372                 struct bio_vec *bvec, unsigned long nr, size_t count,
 373                 size_t seek)
 374 {
 375         iov_iter_bvec(&msg->msg_iter, READ, bvec, nr, count);
 376         return xs_sock_recvmsg(sock, msg, flags, seek);
 377 }
 378
 379 static ssize_t
 380 xs_read_discard(struct socket *sock, struct msghdr *msg, int flags,
 381                 size_t count)
 382 {
 383         iov_iter_discard(&msg->msg_iter, READ, count);
 384         return sock_recvmsg(sock, msg, flags);
 385 }
 386
 387 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 388 static void
 389 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 390 {
 391         struct bvec_iter bi = {
 392                 .bi_size = count,
 393         };
 394         struct bio_vec bv;
 395
 396         bvec_iter_advance(bvec, &bi, seek & PAGE_MASK);
 397         for_each_bvec(bv, bvec, bi, bi)
 398                 flush_dcache_page(bv.bv_page);
 399 }
 400 #else
 401 static inline void
 402 xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek)
 403 {
 404 }
 405 #endif
 406
 407 static ssize_t
 408 xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags,
 409                 struct xdr_buf *buf, size_t count, size_t seek, size_t *read)
 410 {
 411         size_t want, seek_init = seek, offset = 0;
 412         ssize_t ret;
 413
 414         want = min_t(size_t, count, buf->head[0].iov_len);
 415         if (seek < want) {
 416                 ret = xs_read_kvec(sock, msg, flags, &buf->head[0], want, seek);
 417                 if (ret <= 0)
 418                         goto sock_err;
 419                 offset += ret;
 420                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 421                         goto out;
 422                 if (ret != want)
 423                         goto out;
 424                 seek = 0;
 425         } else {
 426                 seek -= want;
 427                 offset += want;
 428         }
 429
 430         want = xs_alloc_sparse_pages(buf,
 431                         min_t(size_t, count - offset, buf->page_len),
 432                         GFP_KERNEL);
 433         if (seek < want) {
 434                 ret = xs_read_bvec(sock, msg, flags, buf->bvec,
 435                                 xdr_buf_pagecount(buf),
 436                                 want + buf->page_base,
 437                                 seek + buf->page_base);
 438                 if (ret <= 0)
 439                         goto sock_err;
 440                 xs_flush_bvec(buf->bvec, ret, seek + buf->page_base);
 441                 ret -= buf->page_base;
 442                 offset += ret;
 443                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 444                         goto out;
 445                 if (ret != want)
 446                         goto out;
 447                 seek = 0;
 448         } else {
 449                 seek -= want;
 450                 offset += want;
 451         }
 452
 453         want = min_t(size_t, count - offset, buf->tail[0].iov_len);
 454         if (seek < want) {
 455                 ret = xs_read_kvec(sock, msg, flags, &buf->tail[0], want, seek);
 456                 if (ret <= 0)
 457                         goto sock_err;
 458                 offset += ret;
 459                 if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 460                         goto out;
 461                 if (ret != want)
 462                         goto out;
 463         } else if (offset < seek_init)
 464                 offset = seek_init;
 465         ret = -EMSGSIZE;
 466 out:
 467         *read = offset - seek_init;
 468         return ret;
 469 sock_err:
 470         offset += seek;
 471         goto out;
 472 }
 473
 474 static void
 475 xs_read_header(struct sock_xprt *transport, struct xdr_buf *buf)
 476 {
 477         if (!transport->recv.copied) {
 478                 if (buf->head[0].iov_len >= transport->recv.offset)
 479                         memcpy(buf->head[0].iov_base,
 480                                         &transport->recv.xid,
 481                                         transport->recv.offset);
 482                 transport->recv.copied = transport->recv.offset;
 483         }
 484 }
 485
 486 static bool
 487 xs_read_stream_request_done(struct sock_xprt *transport)
 488 {
 489         return transport->recv.fraghdr & cpu_to_be32(RPC_LAST_STREAM_FRAGMENT);
 490 }
 491
 492 static void
 493 xs_read_stream_check_eor(struct sock_xprt *transport,
 494                 struct msghdr *msg)
 495 {
 496         if (xs_read_stream_request_done(transport))
 497                 msg->msg_flags |= MSG_EOR;
 498 }
 499
 500 static ssize_t
 501 xs_read_stream_request(struct sock_xprt *transport, struct msghdr *msg,
 502                 int flags, struct rpc_rqst *req)
 503 {
 504         struct xdr_buf *buf = &req->rq_private_buf;
 505         size_t want, read;
 506         ssize_t ret;
 507
 508         xs_read_header(transport, buf);
 509
 510         want = transport->recv.len - transport->recv.offset;
 511         if (want != 0) {
 512                 ret = xs_read_xdr_buf(transport->sock, msg, flags, buf,
 513                                 transport->recv.copied + want,
 514                                 transport->recv.copied,
 515                                 &read);
 516                 transport->recv.offset += read;
 517                 transport->recv.copied += read;
 518         }
 519
 520         if (transport->recv.offset == transport->recv.len)
 521                 xs_read_stream_check_eor(transport, msg);
 522
 523         if (want == 0)
 524                 return 0;
 525
 526         switch (ret) {
 527         default:
 528                 break;
 529         case -EFAULT:
 530         case -EMSGSIZE:
 531                 msg->msg_flags |= MSG_TRUNC;
 532                 return read;
 533         case 0:
 534                 return -ESHUTDOWN;
 535         }
 536         return ret < 0 ? ret : read;
 537 }
 538
 539 static size_t
 540 xs_read_stream_headersize(bool isfrag)
 541 {
 542         if (isfrag)
 543                 return sizeof(__be32);
 544         return 3 * sizeof(__be32);
 545 }
 546
 547 static ssize_t
 548 xs_read_stream_header(struct sock_xprt *transport, struct msghdr *msg,
 549                 int flags, size_t want, size_t seek)
 550 {
 551         struct kvec kvec = {
 552                 .iov_base = &transport->recv.fraghdr,
 553                 .iov_len = want,
 554         };
 555         return xs_read_kvec(transport->sock, msg, flags, &kvec, want, seek);
 556 }
 557
 558 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 559 static ssize_t
 560 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 561 {
 562         struct rpc_xprt *xprt = &transport->xprt;
 563         struct rpc_rqst *req;
 564         ssize_t ret;
 565
 566         /* Is this transport associated with the backchannel? */
 567         if (!xprt->bc_serv)
 568                 return -ESHUTDOWN;
 569
 570         /* Look up and lock the request corresponding to the given XID */
 571         req = xprt_lookup_bc_request(xprt, transport->recv.xid);
 572         if (!req) {
 573                 printk(KERN_WARNING "Callback slot table overflowed\n");
 574                 return -ESHUTDOWN;
 575         }
 576         if (transport->recv.copied && !req->rq_private_buf.len)
 577                 return -ESHUTDOWN;
 578
 579         ret = xs_read_stream_request(transport, msg, flags, req);
 580         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 581                 xprt_complete_bc_request(req, transport->recv.copied);
 582         else
 583                 req->rq_private_buf.len = transport->recv.copied;
 584
 585         return ret;
 586 }
 587 #else /* CONFIG_SUNRPC_BACKCHANNEL */
 588 static ssize_t
 589 xs_read_stream_call(struct sock_xprt *transport, struct msghdr *msg, int flags)
 590 {
 591         return -ESHUTDOWN;
 592 }
 593 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 594
 595 static ssize_t
 596 xs_read_stream_reply(struct sock_xprt *transport, struct msghdr *msg, int flags)
 597 {
 598         struct rpc_xprt *xprt = &transport->xprt;
 599         struct rpc_rqst *req;
 600         ssize_t ret = 0;
 601
 602         /* Look up and lock the request corresponding to the given XID */
 603         spin_lock(&xprt->queue_lock);
 604         req = xprt_lookup_rqst(xprt, transport->recv.xid);
 605         if (!req || (transport->recv.copied && !req->rq_private_buf.len)) {
 606                 msg->msg_flags |= MSG_TRUNC;
 607                 goto out;
 608         }
 609         xprt_pin_rqst(req);
 610         spin_unlock(&xprt->queue_lock);
 611
 612         ret = xs_read_stream_request(transport, msg, flags, req);
 613
 614         spin_lock(&xprt->queue_lock);
 615         if (msg->msg_flags & (MSG_EOR|MSG_TRUNC))
 616                 xprt_complete_rqst(req->rq_task, transport->recv.copied);
 617         else
 618                 req->rq_private_buf.len = transport->recv.copied;
 619         xprt_unpin_rqst(req);
 620 out:
 621         spin_unlock(&xprt->queue_lock);
 622         return ret;
 623 }
 624
 625 static ssize_t
 626 xs_read_stream(struct sock_xprt *transport, int flags)
 627 {
 628         struct msghdr msg = { 0 };
 629         size_t want, read = 0;
 630         ssize_t ret = 0;
 631
 632         if (transport->recv.len == 0) {
 633                 want = xs_read_stream_headersize(transport->recv.copied != 0);
 634                 ret = xs_read_stream_header(transport, &msg, flags, want,
 635                                 transport->recv.offset);
 636                 if (ret <= 0)
 637                         goto out_err;
 638                 transport->recv.offset = ret;
 639                 if (transport->recv.offset != want)
 640                         return transport->recv.offset;
 641                 transport->recv.len = be32_to_cpu(transport->recv.fraghdr) &
 642                         RPC_FRAGMENT_SIZE_MASK;
 643                 transport->recv.offset -= sizeof(transport->recv.fraghdr);
 644                 read = ret;
 645         }
 646
 647         switch (be32_to_cpu(transport->recv.calldir)) {
 648         default:
 649                 msg.msg_flags |= MSG_TRUNC;
 650                 break;
 651         case RPC_CALL:
 652                 ret = xs_read_stream_call(transport, &msg, flags);
 653                 break;
 654         case RPC_REPLY:
 655                 ret = xs_read_stream_reply(transport, &msg, flags);
 656         }
 657         if (msg.msg_flags & MSG_TRUNC) {
 658                 transport->recv.calldir = cpu_to_be32(-1);
 659                 transport->recv.copied = -1;
 660         }
 661         if (ret < 0)
 662                 goto out_err;
 663         read += ret;
 664         if (transport->recv.offset < transport->recv.len) {
 665                 if (!(msg.msg_flags & MSG_TRUNC))
 666                         return read;
 667                 msg.msg_flags = 0;
 668                 ret = xs_read_discard(transport->sock, &msg, flags,
 669                                 transport->recv.len - transport->recv.offset);
 670                 if (ret <= 0)
 671                         goto out_err;
 672                 transport->recv.offset += ret;
 673                 read += ret;
 674                 if (transport->recv.offset != transport->recv.len)
 675                         return read;
 676         }
 677         if (xs_read_stream_request_done(transport)) {
 678                 trace_xs_stream_read_request(transport);
 679                 transport->recv.copied = 0;
 680         }
 681         transport->recv.offset = 0;
 682         transport->recv.len = 0;
 683         return read;
 684 out_err:
 685         return ret != 0 ? ret : -ESHUTDOWN;
 686 }
 687
 688 static __poll_t xs_poll_socket(struct sock_xprt *transport)
 689 {
 690         return transport->sock->ops->poll(transport->file, transport->sock,
 691                         NULL);
 692 }
 693
 694 static bool xs_poll_socket_readable(struct sock_xprt *transport)
 695 {
 696         __poll_t events = xs_poll_socket(transport);
 697
 698         return (events & (EPOLLIN | EPOLLRDNORM)) && !(events & EPOLLRDHUP);
 699 }
 700
 701 static void xs_poll_check_readable(struct sock_xprt *transport)
 702 {
 703
 704         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
 705         if (!xs_poll_socket_readable(transport))
 706                 return;
 707         if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
 708                 queue_work(xprtiod_workqueue, &transport->recv_worker);
 709 }
 710
 711 static void xs_stream_data_receive(struct sock_xprt *transport)
 712 {
 713         size_t read = 0;
 714         ssize_t ret = 0;
 715
 716         mutex_lock(&transport->recv_mutex);
 717         if (transport->sock == NULL)
 718                 goto out;
 719         for (;;) {
 720                 ret = xs_read_stream(transport, MSG_DONTWAIT);
 721                 if (ret < 0)
 722                         break;
 723                 read += ret;
 724                 cond_resched();
 725         }
 726         if (ret == -ESHUTDOWN)
 727                 kernel_sock_shutdown(transport->sock, SHUT_RDWR);
 728         else
 729                 xs_poll_check_readable(transport);
 730 out:
 731         mutex_unlock(&transport->recv_mutex);
 732         trace_xs_stream_read_data(&transport->xprt, ret, read);
 733 }
 734
 735 static void xs_stream_data_receive_workfn(struct work_struct *work)
 736 {
 737         struct sock_xprt *transport =
 738                 container_of(work, struct sock_xprt, recv_worker);
 739         unsigned int pflags = memalloc_nofs_save();
 740
 741         xs_stream_data_receive(transport);
 742         memalloc_nofs_restore(pflags);
 743 }
 744
 745 static void
 746 xs_stream_reset_connect(struct sock_xprt *transport)
 747 {
 748         transport->recv.offset = 0;
 749         transport->recv.len = 0;
 750         transport->recv.copied = 0;
 751         transport->xmit.offset = 0;
 752 }
 753
 754 static void
 755 xs_stream_start_connect(struct sock_xprt *transport)
 756 {
 757         transport->xprt.stat.connect_count++;
 758         transport->xprt.stat.connect_start = jiffies;
 759 }
 760
 761 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 762
 763 /**
 764  * xs_nospace - handle transmit was incomplete
 765  * @req: pointer to RPC request
 766  *
 767  */
 768 static int xs_nospace(struct rpc_rqst *req)
 769 {
 770         struct rpc_xprt *xprt = req->rq_xprt;
 771         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 772         struct sock *sk = transport->inet;
 773         int ret = -EAGAIN;
 774
 775         trace_rpc_socket_nospace(req, transport);
 776
 777         /* Protect against races with write_space */
 778         spin_lock(&xprt->transport_lock);
 779
 780         /* Don't race with disconnect */
 781         if (xprt_connected(xprt)) {
 782                 /* wait for more buffer space */
 783                 sk->sk_write_pending++;
 784                 xprt_wait_for_buffer_space(xprt);
 785         } else
 786                 ret = -ENOTCONN;
 787
 788         spin_unlock(&xprt->transport_lock);
 789
 790         /* Race breaker in case memory is freed before above code is called */
 791         if (ret == -EAGAIN) {
 792                 struct socket_wq *wq;
 793
 794                 rcu_read_lock();
 795                 wq = rcu_dereference(sk->sk_wq);
 796                 set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags);
 797                 rcu_read_unlock();
 798
 799                 sk->sk_write_space(sk);
 800         }
 801         return ret;
 802 }
 803
 804 static void
 805 xs_stream_prepare_request(struct rpc_rqst *req)
 806 {
 807         xdr_free_bvec(&req->rq_rcv_buf);
 808         req->rq_task->tk_status = xdr_alloc_bvec(&req->rq_rcv_buf, GFP_KERNEL);
 809 }
 810
 811 /*
 812  * Determine if the previous message in the stream was aborted before it
 813  * could complete transmission.
 814  */
 815 static bool
 816 xs_send_request_was_aborted(struct sock_xprt *transport, struct rpc_rqst *req)
 817 {
 818         return transport->xmit.offset != 0 && req->rq_bytes_sent == 0;
 819 }
 820
 821 /*
 822  * Return the stream record marker field for a record of length < 2^31-1
 823  */
 824 static rpc_fraghdr
 825 xs_stream_record_marker(struct xdr_buf *xdr)
 826 {
 827         if (!xdr->len)
 828                 return 0;
 829         return cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | (u32)xdr->len);
 830 }
 831
 832 /**
 833  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 834  * @req: pointer to RPC request
 835  *
 836  * Return values:
 837  *        0:    The request has been sent
 838  *   EAGAIN:    The socket was blocked, please call again later to
 839  *              complete the request
 840  * ENOTCONN:    Caller needs to invoke connect logic then call again
 841  *    other:    Some other error occurred, the request was not sent
 842  */
 843 static int xs_local_send_request(struct rpc_rqst *req)
 844 {
 845         struct rpc_xprt *xprt = req->rq_xprt;
 846         struct sock_xprt *transport =
 847                                 container_of(xprt, struct sock_xprt, xprt);
 848         struct xdr_buf *xdr = &req->rq_snd_buf;
 849         rpc_fraghdr rm = xs_stream_record_marker(xdr);
 850         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
 851         struct msghdr msg = {
 852                 .msg_flags      = XS_SENDMSG_FLAGS,
 853         };
 854         unsigned int sent;
 855         int status;
 856
 857         /* Close the stream if the previous transmission was incomplete */
 858         if (xs_send_request_was_aborted(transport, req)) {
 859                 xs_close(xprt);
 860                 return -ENOTCONN;
 861         }
 862
 863         xs_pktdump("packet data:",
 864                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 865
 866         req->rq_xtime = ktime_get();
 867         status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
 868                                    transport->xmit.offset, rm, &sent);
 869         dprintk("RPC:       %s(%u) = %d\n",
 870                         __func__, xdr->len - transport->xmit.offset, status);
 871
 872         if (status == -EAGAIN && sock_writeable(transport->inet))
 873                 status = -ENOBUFS;
 874
 875         if (likely(sent > 0) || status == 0) {
 876                 transport->xmit.offset += sent;
 877                 req->rq_bytes_sent = transport->xmit.offset;
 878                 if (likely(req->rq_bytes_sent >= msglen)) {
 879                         req->rq_xmit_bytes_sent += transport->xmit.offset;
 880                         transport->xmit.offset = 0;
 881                         return 0;
 882                 }
 883                 status = -EAGAIN;
 884         }
 885
 886         switch (status) {
 887         case -ENOBUFS:
 888                 break;
 889         case -EAGAIN:
 890                 status = xs_nospace(req);
 891                 break;
 892         default:
 893                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 894                         -status);
 895                 fallthrough;
 896         case -EPIPE:
 897                 xs_close(xprt);
 898                 status = -ENOTCONN;
 899         }
 900
 901         return status;
 902 }
 903
 904 /**
 905  * xs_udp_send_request - write an RPC request to a UDP socket
 906  * @req: pointer to RPC request
 907  *
 908  * Return values:
 909  *        0:    The request has been sent
 910  *   EAGAIN:    The socket was blocked, please call again later to
 911  *              complete the request
 912  * ENOTCONN:    Caller needs to invoke connect logic then call again
 913  *    other:    Some other error occurred, the request was not sent
 914  */
 915 static int xs_udp_send_request(struct rpc_rqst *req)
 916 {
 917         struct rpc_xprt *xprt = req->rq_xprt;
 918         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 919         struct xdr_buf *xdr = &req->rq_snd_buf;
 920         struct msghdr msg = {
 921                 .msg_name       = xs_addr(xprt),
 922                 .msg_namelen    = xprt->addrlen,
 923                 .msg_flags      = XS_SENDMSG_FLAGS,
 924         };
 925         unsigned int sent;
 926         int status;
 927
 928         xs_pktdump("packet data:",
 929                                 req->rq_svec->iov_base,
 930                                 req->rq_svec->iov_len);
 931
 932         if (!xprt_bound(xprt))
 933                 return -ENOTCONN;
 934
 935         if (!xprt_request_get_cong(xprt, req))
 936                 return -EBADSLT;
 937
 938         req->rq_xtime = ktime_get();
 939         status = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, 0, &sent);
 940
 941         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 942                         xdr->len, status);
 943
 944         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 945         if (status == -EPERM)
 946                 goto process_status;
 947
 948         if (status == -EAGAIN && sock_writeable(transport->inet))
 949                 status = -ENOBUFS;
 950
 951         if (sent > 0 || status == 0) {
 952                 req->rq_xmit_bytes_sent += sent;
 953                 if (sent >= req->rq_slen)
 954                         return 0;
 955                 /* Still some bytes left; set up for a retry later. */
 956                 status = -EAGAIN;
 957         }
 958
 959 process_status:
 960         switch (status) {
 961         case -ENOTSOCK:
 962                 status = -ENOTCONN;
 963                 /* Should we call xs_close() here? */
 964                 break;
 965         case -EAGAIN:
 966                 status = xs_nospace(req);
 967                 break;
 968         case -ENETUNREACH:
 969         case -ENOBUFS:
 970         case -EPIPE:
 971         case -ECONNREFUSED:
 972         case -EPERM:
 973                 /* When the server has died, an ICMP port unreachable message
 974                  * prompts ECONNREFUSED. */
 975                 break;
 976         default:
 977                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 978                         -status);
 979         }
 980
 981         return status;
 982 }
 983
 984 /**
 985  * xs_tcp_send_request - write an RPC request to a TCP socket
 986  * @req: pointer to RPC request
 987  *
 988  * Return values:
 989  *        0:    The request has been sent
 990  *   EAGAIN:    The socket was blocked, please call again later to
 991  *              complete the request
 992  * ENOTCONN:    Caller needs to invoke connect logic then call again
 993  *    other:    Some other error occurred, the request was not sent
 994  *
 995  * XXX: In the case of soft timeouts, should we eventually give up
 996  *      if sendmsg is not able to make progress?
 997  */
 998 static int xs_tcp_send_request(struct rpc_rqst *req)
 999 {
1000         struct rpc_xprt *xprt = req->rq_xprt;
1001         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1002         struct xdr_buf *xdr = &req->rq_snd_buf;
1003         rpc_fraghdr rm = xs_stream_record_marker(xdr);
1004         unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
1005         struct msghdr msg = {
1006                 .msg_flags      = XS_SENDMSG_FLAGS,
1007         };
1008         bool vm_wait = false;
1009         unsigned int sent;
1010         int status;
1011
1012         /* Close the stream if the previous transmission was incomplete */
1013         if (xs_send_request_was_aborted(transport, req)) {
1014                 if (transport->sock != NULL)
1015                         kernel_sock_shutdown(transport->sock, SHUT_RDWR);
1016                 return -ENOTCONN;
1017         }
1018         if (!transport->inet)
1019                 return -ENOTCONN;
1020
1021         xs_pktdump("packet data:",
1022                                 req->rq_svec->iov_base,
1023                                 req->rq_svec->iov_len);
1024
1025         if (test_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state))
1026                 xs_tcp_set_socket_timeouts(xprt, transport->sock);
1027
1028         /* Continue transmitting the packet/record. We must be careful
1029          * to cope with writespace callbacks arriving _after_ we have
1030          * called sendmsg(). */
1031         req->rq_xtime = ktime_get();
1032         tcp_sock_set_cork(transport->inet, true);
1033         while (1) {
1034                 status = xprt_sock_sendmsg(transport->sock, &msg, xdr,
1035                                            transport->xmit.offset, rm, &sent);
1036
1037                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
1038                                 xdr->len - transport->xmit.offset, status);
1039
1040                 /* If we've sent the entire packet, immediately
1041                  * reset the count of bytes sent. */
1042                 transport->xmit.offset += sent;
1043                 req->rq_bytes_sent = transport->xmit.offset;
1044                 if (likely(req->rq_bytes_sent >= msglen)) {
1045                         req->rq_xmit_bytes_sent += transport->xmit.offset;
1046                         transport->xmit.offset = 0;
1047                         if (atomic_long_read(&xprt->xmit_queuelen) == 1)
1048                                 tcp_sock_set_cork(transport->inet, false);
1049                         return 0;
1050                 }
1051
1052                 WARN_ON_ONCE(sent == 0 && status == 0);
1053
1054                 if (status == -EAGAIN ) {
1055                         /*
1056                          * Return EAGAIN if we're sure we're hitting the
1057                          * socket send buffer limits.
1058                          */
1059                         if (test_bit(SOCK_NOSPACE, &transport->sock->flags))
1060                                 break;
1061                         /*
1062                          * Did we hit a memory allocation failure?
1063                          */
1064                         if (sent == 0) {
1065                                 status = -ENOBUFS;
1066                                 if (vm_wait)
1067                                         break;
1068                                 /* Retry, knowing now that we're below the
1069                                  * socket send buffer limit
1070                                  */
1071                                 vm_wait = true;
1072                         }
1073                         continue;
1074                 }
1075                 if (status < 0)
1076                         break;
1077                 vm_wait = false;
1078         }
1079
1080         switch (status) {
1081         case -ENOTSOCK:
1082                 status = -ENOTCONN;
1083                 /* Should we call xs_close() here? */
1084                 break;
1085         case -EAGAIN:
1086                 status = xs_nospace(req);
1087                 break;
1088         case -ECONNRESET:
1089         case -ECONNREFUSED:
1090         case -ENOTCONN:
1091         case -EADDRINUSE:
1092         case -ENOBUFS:
1093         case -EPIPE:
1094                 break;
1095         default:
1096                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
1097                         -status);
1098         }
1099
1100         return status;
1101 }
1102
1103 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1104 {
1105         transport->old_data_ready = sk->sk_data_ready;
1106         transport->old_state_change = sk->sk_state_change;
1107         transport->old_write_space = sk->sk_write_space;
1108         transport->old_error_report = sk->sk_error_report;
1109 }
1110
1111 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
1112 {
1113         sk->sk_data_ready = transport->old_data_ready;
1114         sk->sk_state_change = transport->old_state_change;
1115         sk->sk_write_space = transport->old_write_space;
1116         sk->sk_error_report = transport->old_error_report;
1117 }
1118
1119 static void xs_sock_reset_state_flags(struct rpc_xprt *xprt)
1120 {
1121         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1122
1123         clear_bit(XPRT_SOCK_DATA_READY, &transport->sock_state);
1124         clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state);
1125         clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state);
1126         clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state);
1127 }
1128
1129 static void xs_run_error_worker(struct sock_xprt *transport, unsigned int nr)
1130 {
1131         set_bit(nr, &transport->sock_state);
1132         queue_work(xprtiod_workqueue, &transport->error_worker);
1133 }
1134
1135 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1136 {
1137         xprt->connect_cookie++;
1138         smp_mb__before_atomic();
1139         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1140         clear_bit(XPRT_CLOSING, &xprt->state);
1141         xs_sock_reset_state_flags(xprt);
1142         smp_mb__after_atomic();
1143 }
1144
1145 /**
1146  * xs_error_report - callback to handle TCP socket state errors
1147  * @sk: socket
1148  *
1149  * Note: we don't call sock_error() since there may be a rpc_task
1150  * using the socket, and so we don't want to clear sk->sk_err.
1151  */
1152 static void xs_error_report(struct sock *sk)
1153 {
1154         struct sock_xprt *transport;
1155         struct rpc_xprt *xprt;
1156
1157         if (!(xprt = xprt_from_sock(sk)))
1158                 return;
1159
1160         transport = container_of(xprt, struct sock_xprt, xprt);
1161         transport->xprt_err = -sk->sk_err;
1162         if (transport->xprt_err == 0)
1163                 return;
1164         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
1165                         xprt, -transport->xprt_err);
1166         trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
1167
1168         /* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
1169         smp_mb__before_atomic();
1170         xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
1171 }
1172
1173 static void xs_reset_transport(struct sock_xprt *transport)
1174 {
1175         struct socket *sock = transport->sock;
1176         struct sock *sk = transport->inet;
1177         struct rpc_xprt *xprt = &transport->xprt;
1178         struct file *filp = transport->file;
1179
1180         if (sk == NULL)
1181                 return;
1182
1183         if (atomic_read(&transport->xprt.swapper))
1184                 sk_clear_memalloc(sk);
1185
1186         kernel_sock_shutdown(sock, SHUT_RDWR);
1187
1188         mutex_lock(&transport->recv_mutex);
1189         lock_sock(sk);
1190         transport->inet = NULL;
1191         transport->sock = NULL;
1192         transport->file = NULL;
1193
1194         sk->sk_user_data = NULL;
1195
1196         xs_restore_old_callbacks(transport, sk);
1197         xprt_clear_connected(xprt);
1198         xs_sock_reset_connection_flags(xprt);
1199         /* Reset stream record info */
1200         xs_stream_reset_connect(transport);
1201         release_sock(sk);
1202         mutex_unlock(&transport->recv_mutex);
1203
1204         trace_rpc_socket_close(xprt, sock);
1205         fput(filp);
1206
1207         xprt_disconnect_done(xprt);
1208 }
1209
1210 /**
1211  * xs_close - close a socket
1212  * @xprt: transport
1213  *
1214  * This is used when all requests are complete; ie, no DRC state remains
1215  * on the server we want to save.
1216  *
1217  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1218  * xs_reset_transport() zeroing the socket from underneath a writer.
1219  */
1220 static void xs_close(struct rpc_xprt *xprt)
1221 {
1222         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1223
1224         dprintk("RPC:       xs_close xprt %p\n", xprt);
1225
1226         xs_reset_transport(transport);
1227         xprt->reestablish_timeout = 0;
1228 }
1229
1230 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1231 {
1232         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1233                 xprt);
1234         xprt_disconnect_done(xprt);
1235 }
1236
1237 static void xs_xprt_free(struct rpc_xprt *xprt)
1238 {
1239         xs_free_peer_addresses(xprt);
1240         xprt_free(xprt);
1241 }
1242
1243 /**
1244  * xs_destroy - prepare to shutdown a transport
1245  * @xprt: doomed transport
1246  *
1247  */
1248 static void xs_destroy(struct rpc_xprt *xprt)
1249 {
1250         struct sock_xprt *transport = container_of(xprt,
1251                         struct sock_xprt, xprt);
1252         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1253
1254         cancel_delayed_work_sync(&transport->connect_worker);
1255         xs_close(xprt);
1256         cancel_work_sync(&transport->recv_worker);
1257         cancel_work_sync(&transport->error_worker);
1258         xs_xprt_free(xprt);
1259         module_put(THIS_MODULE);
1260 }
1261
1262 /**
1263  * xs_udp_data_read_skb - receive callback for UDP sockets
1264  * @xprt: transport
1265  * @sk: socket
1266  * @skb: skbuff
1267  *
1268  */
1269 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1270                 struct sock *sk,
1271                 struct sk_buff *skb)
1272 {
1273         struct rpc_task *task;
1274         struct rpc_rqst *rovr;
1275         int repsize, copied;
1276         u32 _xid;
1277         __be32 *xp;
1278
1279         repsize = skb->len;
1280         if (repsize < 4) {
1281                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1282                 return;
1283         }
1284
1285         /* Copy the XID from the skb... */
1286         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1287         if (xp == NULL)
1288                 return;
1289
1290         /* Look up and lock the request corresponding to the given XID */
1291         spin_lock(&xprt->queue_lock);
1292         rovr = xprt_lookup_rqst(xprt, *xp);
1293         if (!rovr)
1294                 goto out_unlock;
1295         xprt_pin_rqst(rovr);
1296         xprt_update_rtt(rovr->rq_task);
1297         spin_unlock(&xprt->queue_lock);
1298         task = rovr->rq_task;
1299
1300         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1301                 copied = repsize;
1302
1303         /* Suck it into the iovec, verify checksum if not done by hw. */
1304         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1305                 spin_lock(&xprt->queue_lock);
1306                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1307                 goto out_unpin;
1308         }
1309
1310
1311         spin_lock(&xprt->transport_lock);
1312         xprt_adjust_cwnd(xprt, task, copied);
1313         spin_unlock(&xprt->transport_lock);
1314         spin_lock(&xprt->queue_lock);
1315         xprt_complete_rqst(task, copied);
1316         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1317 out_unpin:
1318         xprt_unpin_rqst(rovr);
1319  out_unlock:
1320         spin_unlock(&xprt->queue_lock);
1321 }
1322
1323 static void xs_udp_data_receive(struct sock_xprt *transport)
1324 {
1325         struct sk_buff *skb;
1326         struct sock *sk;
1327         int err;
1328
1329         mutex_lock(&transport->recv_mutex);
1330         sk = transport->inet;
1331         if (sk == NULL)
1332                 goto out;
1333         for (;;) {
1334                 skb = skb_recv_udp(sk, 0, 1, &err);
1335                 if (skb == NULL)
1336                         break;
1337                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1338                 consume_skb(skb);
1339                 cond_resched();
1340         }
1341         xs_poll_check_readable(transport);
1342 out:
1343         mutex_unlock(&transport->recv_mutex);
1344 }
1345
1346 static void xs_udp_data_receive_workfn(struct work_struct *work)
1347 {
1348         struct sock_xprt *transport =
1349                 container_of(work, struct sock_xprt, recv_worker);
1350         unsigned int pflags = memalloc_nofs_save();
1351
1352         xs_udp_data_receive(transport);
1353         memalloc_nofs_restore(pflags);
1354 }
1355
1356 /**
1357  * xs_data_ready - "data ready" callback for UDP sockets
1358  * @sk: socket with data to read
1359  *
1360  */
1361 static void xs_data_ready(struct sock *sk)
1362 {
1363         struct rpc_xprt *xprt;
1364
1365         dprintk("RPC:       xs_data_ready...\n");
1366         xprt = xprt_from_sock(sk);
1367         if (xprt != NULL) {
1368                 struct sock_xprt *transport = container_of(xprt,
1369                                 struct sock_xprt, xprt);
1370                 transport->old_data_ready(sk);
1371                 /* Any data means we had a useful conversation, so
1372                  * then we don't need to delay the next reconnect
1373                  */
1374                 if (xprt->reestablish_timeout)
1375                         xprt->reestablish_timeout = 0;
1376                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1377                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1378         }
1379 }
1380
1381 /*
1382  * Helper function to force a TCP close if the server is sending
1383  * junk and/or it has put us in CLOSE_WAIT
1384  */
1385 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1386 {
1387         xprt_force_disconnect(xprt);
1388 }
1389
1390 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1391 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1392 {
1393         return PAGE_SIZE;
1394 }
1395 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1396
1397 /**
1398  * xs_tcp_state_change - callback to handle TCP socket state changes
1399  * @sk: socket whose state has changed
1400  *
1401  */
1402 static void xs_tcp_state_change(struct sock *sk)
1403 {
1404         struct rpc_xprt *xprt;
1405         struct sock_xprt *transport;
1406
1407         if (!(xprt = xprt_from_sock(sk)))
1408                 return;
1409         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1410         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1411                         sk->sk_state, xprt_connected(xprt),
1412                         sock_flag(sk, SOCK_DEAD),
1413                         sock_flag(sk, SOCK_ZAPPED),
1414                         sk->sk_shutdown);
1415
1416         transport = container_of(xprt, struct sock_xprt, xprt);
1417         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1418         switch (sk->sk_state) {
1419         case TCP_ESTABLISHED:
1420                 if (!xprt_test_and_set_connected(xprt)) {
1421                         xprt->connect_cookie++;
1422                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1423                         xprt_clear_connecting(xprt);
1424
1425                         xprt->stat.connect_count++;
1426                         xprt->stat.connect_time += (long)jiffies -
1427                                                    xprt->stat.connect_start;
1428                         xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1429                 }
1430                 break;
1431         case TCP_FIN_WAIT1:
1432                 /* The client initiated a shutdown of the socket */
1433                 xprt->connect_cookie++;
1434                 xprt->reestablish_timeout = 0;
1435                 set_bit(XPRT_CLOSING, &xprt->state);
1436                 smp_mb__before_atomic();
1437                 clear_bit(XPRT_CONNECTED, &xprt->state);
1438                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1439                 smp_mb__after_atomic();
1440                 break;
1441         case TCP_CLOSE_WAIT:
1442                 /* The server initiated a shutdown of the socket */
1443                 xprt->connect_cookie++;
1444                 clear_bit(XPRT_CONNECTED, &xprt->state);
1445                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1446                 fallthrough;
1447         case TCP_CLOSING:
1448                 /*
1449                  * If the server closed down the connection, make sure that
1450                  * we back off before reconnecting
1451                  */
1452                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1453                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1454                 break;
1455         case TCP_LAST_ACK:
1456                 set_bit(XPRT_CLOSING, &xprt->state);
1457                 smp_mb__before_atomic();
1458                 clear_bit(XPRT_CONNECTED, &xprt->state);
1459                 smp_mb__after_atomic();
1460                 break;
1461         case TCP_CLOSE:
1462                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1463                                         &transport->sock_state))
1464                         xprt_clear_connecting(xprt);
1465                 clear_bit(XPRT_CLOSING, &xprt->state);
1466                 /* Trigger the socket release */
1467                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1468         }
1469 }
1470
1471 static void xs_write_space(struct sock *sk)
1472 {
1473         struct socket_wq *wq;
1474         struct sock_xprt *transport;
1475         struct rpc_xprt *xprt;
1476
1477         if (!sk->sk_socket)
1478                 return;
1479         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1480
1481         if (unlikely(!(xprt = xprt_from_sock(sk))))
1482                 return;
1483         transport = container_of(xprt, struct sock_xprt, xprt);
1484         rcu_read_lock();
1485         wq = rcu_dereference(sk->sk_wq);
1486         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1487                 goto out;
1488
1489         xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1490         sk->sk_write_pending--;
1491 out:
1492         rcu_read_unlock();
1493 }
1494
1495 /**
1496  * xs_udp_write_space - callback invoked when socket buffer space
1497  *                             becomes available
1498  * @sk: socket whose state has changed
1499  *
1500  * Called when more output buffer space is available for this socket.
1501  * We try not to wake our writers until they can make "significant"
1502  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1503  * with a bunch of small requests.
1504  */
1505 static void xs_udp_write_space(struct sock *sk)
1506 {
1507         /* from net/core/sock.c:sock_def_write_space */
1508         if (sock_writeable(sk))
1509                 xs_write_space(sk);
1510 }
1511
1512 /**
1513  * xs_tcp_write_space - callback invoked when socket buffer space
1514  *                             becomes available
1515  * @sk: socket whose state has changed
1516  *
1517  * Called when more output buffer space is available for this socket.
1518  * We try not to wake our writers until they can make "significant"
1519  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1520  * with a bunch of small requests.
1521  */
1522 static void xs_tcp_write_space(struct sock *sk)
1523 {
1524         /* from net/core/stream.c:sk_stream_write_space */
1525         if (sk_stream_is_writeable(sk))
1526                 xs_write_space(sk);
1527 }
1528
1529 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1530 {
1531         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1532         struct sock *sk = transport->inet;
1533
1534         if (transport->rcvsize) {
1535                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1536                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1537         }
1538         if (transport->sndsize) {
1539                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1540                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1541                 sk->sk_write_space(sk);
1542         }
1543 }
1544
1545 /**
1546  * xs_udp_set_buffer_size - set send and receive limits
1547  * @xprt: generic transport
1548  * @sndsize: requested size of send buffer, in bytes
1549  * @rcvsize: requested size of receive buffer, in bytes
1550  *
1551  * Set socket send and receive buffer size limits.
1552  */
1553 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1554 {
1555         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1556
1557         transport->sndsize = 0;
1558         if (sndsize)
1559                 transport->sndsize = sndsize + 1024;
1560         transport->rcvsize = 0;
1561         if (rcvsize)
1562                 transport->rcvsize = rcvsize + 1024;
1563
1564         xs_udp_do_set_buffer_size(xprt);
1565 }
1566
1567 /**
1568  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1569  * @xprt: controlling transport
1570  * @task: task that timed out
1571  *
1572  * Adjust the congestion window after a retransmit timeout has occurred.
1573  */
1574 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1575 {
1576         spin_lock(&xprt->transport_lock);
1577         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1578         spin_unlock(&xprt->transport_lock);
1579 }
1580
1581 static int xs_get_random_port(void)
1582 {
1583         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1584         unsigned short range;
1585         unsigned short rand;
1586
1587         if (max < min)
1588                 return -EADDRINUSE;
1589         range = max - min + 1;
1590         rand = (unsigned short) prandom_u32() % range;
1591         return rand + min;
1592 }
1593
1594 static unsigned short xs_sock_getport(struct socket *sock)
1595 {
1596         struct sockaddr_storage buf;
1597         unsigned short port = 0;
1598
1599         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1600                 goto out;
1601         switch (buf.ss_family) {
1602         case AF_INET6:
1603                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1604                 break;
1605         case AF_INET:
1606                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1607         }
1608 out:
1609         return port;
1610 }
1611
1612 /**
1613  * xs_set_port - reset the port number in the remote endpoint address
1614  * @xprt: generic transport
1615  * @port: new port number
1616  *
1617  */
1618 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1619 {
1620         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1621
1622         rpc_set_port(xs_addr(xprt), port);
1623         xs_update_peer_port(xprt);
1624 }
1625
1626 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1627 {
1628         if (transport->srcport == 0 && transport->xprt.reuseport)
1629                 transport->srcport = xs_sock_getport(sock);
1630 }
1631
1632 static int xs_get_srcport(struct sock_xprt *transport)
1633 {
1634         int port = transport->srcport;
1635
1636         if (port == 0 && transport->xprt.resvport)
1637                 port = xs_get_random_port();
1638         return port;
1639 }
1640
1641 unsigned short get_srcport(struct rpc_xprt *xprt)
1642 {
1643         struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1644         return xs_sock_getport(sock->sock);
1645 }
1646 EXPORT_SYMBOL(get_srcport);
1647
1648 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1649 {
1650         if (transport->srcport != 0)
1651                 transport->srcport = 0;
1652         if (!transport->xprt.resvport)
1653                 return 0;
1654         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1655                 return xprt_max_resvport;
1656         return --port;
1657 }
1658 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1659 {
1660         struct sockaddr_storage myaddr;
1661         int err, nloop = 0;
1662         int port = xs_get_srcport(transport);
1663         unsigned short last;
1664
1665         /*
1666          * If we are asking for any ephemeral port (i.e. port == 0 &&
1667          * transport->xprt.resvport == 0), don't bind.  Let the local
1668          * port selection happen implicitly when the socket is used
1669          * (for example at connect time).
1670          *
1671          * This ensures that we can continue to establish TCP
1672          * connections even when all local ephemeral ports are already
1673          * a part of some TCP connection.  This makes no difference
1674          * for UDP sockets, but also doesn't harm them.
1675          *
1676          * If we're asking for any reserved port (i.e. port == 0 &&
1677          * transport->xprt.resvport == 1) xs_get_srcport above will
1678          * ensure that port is non-zero and we will bind as needed.
1679          */
1680         if (port <= 0)
1681                 return port;
1682
1683         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1684         do {
1685                 rpc_set_port((struct sockaddr *)&myaddr, port);
1686                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1687                                 transport->xprt.addrlen);
1688                 if (err == 0) {
1689                         if (transport->xprt.reuseport)
1690                                 transport->srcport = port;
1691                         break;
1692                 }
1693                 last = port;
1694                 port = xs_next_srcport(transport, port);
1695                 if (port > last)
1696                         nloop++;
1697         } while (err == -EADDRINUSE && nloop != 2);
1698
1699         if (myaddr.ss_family == AF_INET)
1700                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1701                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1702                                 port, err ? "failed" : "ok", err);
1703         else
1704                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1705                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1706                                 port, err ? "failed" : "ok", err);
1707         return err;
1708 }
1709
1710 /*
1711  * We don't support autobind on AF_LOCAL sockets
1712  */
1713 static void xs_local_rpcbind(struct rpc_task *task)
1714 {
1715         xprt_set_bound(task->tk_xprt);
1716 }
1717
1718 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1719 {
1720 }
1721
1722 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1723 static struct lock_class_key xs_key[3];
1724 static struct lock_class_key xs_slock_key[3];
1725
1726 static inline void xs_reclassify_socketu(struct socket *sock)
1727 {
1728         struct sock *sk = sock->sk;
1729
1730         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1731                 &xs_slock_key[0], "sk_lock-AF_LOCAL-RPC", &xs_key[0]);
1732 }
1733
1734 static inline void xs_reclassify_socket4(struct socket *sock)
1735 {
1736         struct sock *sk = sock->sk;
1737
1738         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1739                 &xs_slock_key[1], "sk_lock-AF_INET-RPC", &xs_key[1]);
1740 }
1741
1742 static inline void xs_reclassify_socket6(struct socket *sock)
1743 {
1744         struct sock *sk = sock->sk;
1745
1746         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1747                 &xs_slock_key[2], "sk_lock-AF_INET6-RPC", &xs_key[2]);
1748 }
1749
1750 static inline void xs_reclassify_socket(int family, struct socket *sock)
1751 {
1752         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1753                 return;
1754
1755         switch (family) {
1756         case AF_LOCAL:
1757                 xs_reclassify_socketu(sock);
1758                 break;
1759         case AF_INET:
1760                 xs_reclassify_socket4(sock);
1761                 break;
1762         case AF_INET6:
1763                 xs_reclassify_socket6(sock);
1764                 break;
1765         }
1766 }
1767 #else
1768 static inline void xs_reclassify_socket(int family, struct socket *sock)
1769 {
1770 }
1771 #endif
1772
1773 static void xs_dummy_setup_socket(struct work_struct *work)
1774 {
1775 }
1776
1777 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1778                 struct sock_xprt *transport, int family, int type,
1779                 int protocol, bool reuseport)
1780 {
1781         struct file *filp;
1782         struct socket *sock;
1783         int err;
1784
1785         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1786         if (err < 0) {
1787                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1788                                 protocol, -err);
1789                 goto out;
1790         }
1791         xs_reclassify_socket(family, sock);
1792
1793         if (reuseport)
1794                 sock_set_reuseport(sock->sk);
1795
1796         err = xs_bind(transport, sock);
1797         if (err) {
1798                 sock_release(sock);
1799                 goto out;
1800         }
1801
1802         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1803         if (IS_ERR(filp))
1804                 return ERR_CAST(filp);
1805         transport->file = filp;
1806
1807         return sock;
1808 out:
1809         return ERR_PTR(err);
1810 }
1811
1812 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1813                                       struct socket *sock)
1814 {
1815         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1816                                                                         xprt);
1817
1818         if (!transport->inet) {
1819                 struct sock *sk = sock->sk;
1820
1821                 lock_sock(sk);
1822
1823                 xs_save_old_callbacks(transport, sk);
1824
1825                 sk->sk_user_data = xprt;
1826                 sk->sk_data_ready = xs_data_ready;
1827                 sk->sk_write_space = xs_udp_write_space;
1828                 sock_set_flag(sk, SOCK_FASYNC);
1829                 sk->sk_error_report = xs_error_report;
1830
1831                 xprt_clear_connected(xprt);
1832
1833                 /* Reset to new socket */
1834                 transport->sock = sock;
1835                 transport->inet = sk;
1836
1837                 release_sock(sk);
1838         }
1839
1840         xs_stream_start_connect(transport);
1841
1842         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1843 }
1844
1845 /**
1846  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1847  * @transport: socket transport to connect
1848  */
1849 static int xs_local_setup_socket(struct sock_xprt *transport)
1850 {
1851         struct rpc_xprt *xprt = &transport->xprt;
1852         struct file *filp;
1853         struct socket *sock;
1854         int status;
1855
1856         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1857                                         SOCK_STREAM, 0, &sock, 1);
1858         if (status < 0) {
1859                 dprintk("RPC:       can't create AF_LOCAL "
1860                         "transport socket (%d).\n", -status);
1861                 goto out;
1862         }
1863         xs_reclassify_socket(AF_LOCAL, sock);
1864
1865         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1866         if (IS_ERR(filp)) {
1867                 status = PTR_ERR(filp);
1868                 goto out;
1869         }
1870         transport->file = filp;
1871
1872         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1873                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1874
1875         status = xs_local_finish_connecting(xprt, sock);
1876         trace_rpc_socket_connect(xprt, sock, status);
1877         switch (status) {
1878         case 0:
1879                 dprintk("RPC:       xprt %p connected to %s\n",
1880                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1881                 xprt->stat.connect_count++;
1882                 xprt->stat.connect_time += (long)jiffies -
1883                                            xprt->stat.connect_start;
1884                 xprt_set_connected(xprt);
1885                 break;
1886         case -ENOBUFS:
1887                 break;
1888         case -ENOENT:
1889                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1890                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1891                 break;
1892         case -ECONNREFUSED:
1893                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1894                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1895                 break;
1896         default:
1897                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1898                                 __func__, -status,
1899                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1900         }
1901
1902 out:
1903         xprt_clear_connecting(xprt);
1904         xprt_wake_pending_tasks(xprt, status);
1905         return status;
1906 }
1907
1908 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1909 {
1910         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1911         int ret;
1912
1913          if (RPC_IS_ASYNC(task)) {
1914                 /*
1915                  * We want the AF_LOCAL connect to be resolved in the
1916                  * filesystem namespace of the process making the rpc
1917                  * call.  Thus we connect synchronously.
1918                  *
1919                  * If we want to support asynchronous AF_LOCAL calls,
1920                  * we'll need to figure out how to pass a namespace to
1921                  * connect.
1922                  */
1923                 task->tk_rpc_status = -ENOTCONN;
1924                 rpc_exit(task, -ENOTCONN);
1925                 return;
1926         }
1927         ret = xs_local_setup_socket(transport);
1928         if (ret && !RPC_IS_SOFTCONN(task))
1929                 msleep_interruptible(15000);
1930 }
1931
1932 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1933 /*
1934  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1935  * know that we have exclusive access to the socket), to guard against
1936  * races with xs_reset_transport.
1937  */
1938 static void xs_set_memalloc(struct rpc_xprt *xprt)
1939 {
1940         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1941                         xprt);
1942
1943         /*
1944          * If there's no sock, then we have nothing to set. The
1945          * reconnecting process will get it for us.
1946          */
1947         if (!transport->inet)
1948                 return;
1949         if (atomic_read(&xprt->swapper))
1950                 sk_set_memalloc(transport->inet);
1951 }
1952
1953 /**
1954  * xs_enable_swap - Tag this transport as being used for swap.
1955  * @xprt: transport to tag
1956  *
1957  * Take a reference to this transport on behalf of the rpc_clnt, and
1958  * optionally mark it for swapping if it wasn't already.
1959  */
1960 static int
1961 xs_enable_swap(struct rpc_xprt *xprt)
1962 {
1963         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1964
1965         if (atomic_inc_return(&xprt->swapper) != 1)
1966                 return 0;
1967         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1968                 return -ERESTARTSYS;
1969         if (xs->inet)
1970                 sk_set_memalloc(xs->inet);
1971         xprt_release_xprt(xprt, NULL);
1972         return 0;
1973 }
1974
1975 /**
1976  * xs_disable_swap - Untag this transport as being used for swap.
1977  * @xprt: transport to tag
1978  *
1979  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
1980  * swapper refcount goes to 0, untag the socket as a memalloc socket.
1981  */
1982 static void
1983 xs_disable_swap(struct rpc_xprt *xprt)
1984 {
1985         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1986
1987         if (!atomic_dec_and_test(&xprt->swapper))
1988                 return;
1989         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1990                 return;
1991         if (xs->inet)
1992                 sk_clear_memalloc(xs->inet);
1993         xprt_release_xprt(xprt, NULL);
1994 }
1995 #else
1996 static void xs_set_memalloc(struct rpc_xprt *xprt)
1997 {
1998 }
1999
2000 static int
2001 xs_enable_swap(struct rpc_xprt *xprt)
2002 {
2003         return -EINVAL;
2004 }
2005
2006 static void
2007 xs_disable_swap(struct rpc_xprt *xprt)
2008 {
2009 }
2010 #endif
2011
2012 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2013 {
2014         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2015
2016         if (!transport->inet) {
2017                 struct sock *sk = sock->sk;
2018
2019                 lock_sock(sk);
2020
2021                 xs_save_old_callbacks(transport, sk);
2022
2023                 sk->sk_user_data = xprt;
2024                 sk->sk_data_ready = xs_data_ready;
2025                 sk->sk_write_space = xs_udp_write_space;
2026                 sock_set_flag(sk, SOCK_FASYNC);
2027
2028                 xprt_set_connected(xprt);
2029
2030                 /* Reset to new socket */
2031                 transport->sock = sock;
2032                 transport->inet = sk;
2033
2034                 xs_set_memalloc(xprt);
2035
2036                 release_sock(sk);
2037         }
2038         xs_udp_do_set_buffer_size(xprt);
2039
2040         xprt->stat.connect_start = jiffies;
2041 }
2042
2043 static void xs_udp_setup_socket(struct work_struct *work)
2044 {
2045         struct sock_xprt *transport =
2046                 container_of(work, struct sock_xprt, connect_worker.work);
2047         struct rpc_xprt *xprt = &transport->xprt;
2048         struct socket *sock;
2049         int status = -EIO;
2050
2051         sock = xs_create_sock(xprt, transport,
2052                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2053                         IPPROTO_UDP, false);
2054         if (IS_ERR(sock))
2055                 goto out;
2056
2057         dprintk("RPC:       worker connecting xprt %p via %s to "
2058                                 "%s (port %s)\n", xprt,
2059                         xprt->address_strings[RPC_DISPLAY_PROTO],
2060                         xprt->address_strings[RPC_DISPLAY_ADDR],
2061                         xprt->address_strings[RPC_DISPLAY_PORT]);
2062
2063         xs_udp_finish_connecting(xprt, sock);
2064         trace_rpc_socket_connect(xprt, sock, 0);
2065         status = 0;
2066 out:
2067         xprt_clear_connecting(xprt);
2068         xprt_unlock_connect(xprt, transport);
2069         xprt_wake_pending_tasks(xprt, status);
2070 }
2071
2072 /**
2073  * xs_tcp_shutdown - gracefully shut down a TCP socket
2074  * @xprt: transport
2075  *
2076  * Initiates a graceful shutdown of the TCP socket by calling the
2077  * equivalent of shutdown(SHUT_RDWR);
2078  */
2079 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2080 {
2081         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2082         struct socket *sock = transport->sock;
2083         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2084
2085         if (sock == NULL)
2086                 return;
2087         if (!xprt->reuseport) {
2088                 xs_close(xprt);
2089                 return;
2090         }
2091         switch (skst) {
2092         case TCP_FIN_WAIT1:
2093         case TCP_FIN_WAIT2:
2094                 break;
2095         case TCP_ESTABLISHED:
2096         case TCP_CLOSE_WAIT:
2097                 kernel_sock_shutdown(sock, SHUT_RDWR);
2098                 trace_rpc_socket_shutdown(xprt, sock);
2099                 break;
2100         default:
2101                 xs_reset_transport(transport);
2102         }
2103 }
2104
2105 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2106                 struct socket *sock)
2107 {
2108         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2109         unsigned int keepidle;
2110         unsigned int keepcnt;
2111         unsigned int timeo;
2112
2113         spin_lock(&xprt->transport_lock);
2114         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2115         keepcnt = xprt->timeout->to_retries + 1;
2116         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2117                 (xprt->timeout->to_retries + 1);
2118         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2119         spin_unlock(&xprt->transport_lock);
2120
2121         /* TCP Keepalive options */
2122         sock_set_keepalive(sock->sk);
2123         tcp_sock_set_keepidle(sock->sk, keepidle);
2124         tcp_sock_set_keepintvl(sock->sk, keepidle);
2125         tcp_sock_set_keepcnt(sock->sk, keepcnt);
2126
2127         /* TCP user timeout (see RFC5482) */
2128         tcp_sock_set_user_timeout(sock->sk, timeo);
2129 }
2130
2131 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2132                 unsigned long connect_timeout,
2133                 unsigned long reconnect_timeout)
2134 {
2135         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2136         struct rpc_timeout to;
2137         unsigned long initval;
2138
2139         spin_lock(&xprt->transport_lock);
2140         if (reconnect_timeout < xprt->max_reconnect_timeout)
2141                 xprt->max_reconnect_timeout = reconnect_timeout;
2142         if (connect_timeout < xprt->connect_timeout) {
2143                 memcpy(&to, xprt->timeout, sizeof(to));
2144                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2145                 /* Arbitrary lower limit */
2146                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2147                         initval = XS_TCP_INIT_REEST_TO << 1;
2148                 to.to_initval = initval;
2149                 to.to_maxval = initval;
2150                 memcpy(&transport->tcp_timeout, &to,
2151                                 sizeof(transport->tcp_timeout));
2152                 xprt->timeout = &transport->tcp_timeout;
2153                 xprt->connect_timeout = connect_timeout;
2154         }
2155         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2156         spin_unlock(&xprt->transport_lock);
2157 }
2158
2159 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2160 {
2161         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2162
2163         if (!transport->inet) {
2164                 struct sock *sk = sock->sk;
2165
2166                 /* Avoid temporary address, they are bad for long-lived
2167                  * connections such as NFS mounts.
2168                  * RFC4941, section 3.6 suggests that:
2169                  *    Individual applications, which have specific
2170                  *    knowledge about the normal duration of connections,
2171                  *    MAY override this as appropriate.
2172                  */
2173                 if (xs_addr(xprt)->sa_family == PF_INET6) {
2174                         ip6_sock_set_addr_preferences(sk,
2175                                 IPV6_PREFER_SRC_PUBLIC);
2176                 }
2177
2178                 xs_tcp_set_socket_timeouts(xprt, sock);
2179                 tcp_sock_set_nodelay(sk);
2180
2181                 lock_sock(sk);
2182
2183                 xs_save_old_callbacks(transport, sk);
2184
2185                 sk->sk_user_data = xprt;
2186                 sk->sk_data_ready = xs_data_ready;
2187                 sk->sk_state_change = xs_tcp_state_change;
2188                 sk->sk_write_space = xs_tcp_write_space;
2189                 sock_set_flag(sk, SOCK_FASYNC);
2190                 sk->sk_error_report = xs_error_report;
2191
2192                 /* socket options */
2193                 sock_reset_flag(sk, SOCK_LINGER);
2194
2195                 xprt_clear_connected(xprt);
2196
2197                 /* Reset to new socket */
2198                 transport->sock = sock;
2199                 transport->inet = sk;
2200
2201                 release_sock(sk);
2202         }
2203
2204         if (!xprt_bound(xprt))
2205                 return -ENOTCONN;
2206
2207         xs_set_memalloc(xprt);
2208
2209         xs_stream_start_connect(transport);
2210
2211         /* Tell the socket layer to start connecting... */
2212         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2213         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2214 }
2215
2216 /**
2217  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2218  * @work: queued work item
2219  *
2220  * Invoked by a work queue tasklet.
2221  */
2222 static void xs_tcp_setup_socket(struct work_struct *work)
2223 {
2224         struct sock_xprt *transport =
2225                 container_of(work, struct sock_xprt, connect_worker.work);
2226         struct socket *sock = transport->sock;
2227         struct rpc_xprt *xprt = &transport->xprt;
2228         int status;
2229
2230         if (!sock) {
2231                 sock = xs_create_sock(xprt, transport,
2232                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2233                                 IPPROTO_TCP, true);
2234                 if (IS_ERR(sock)) {
2235                         xprt_wake_pending_tasks(xprt, PTR_ERR(sock));
2236                         goto out;
2237                 }
2238         }
2239
2240         dprintk("RPC:       worker connecting xprt %p via %s to "
2241                                 "%s (port %s)\n", xprt,
2242                         xprt->address_strings[RPC_DISPLAY_PROTO],
2243                         xprt->address_strings[RPC_DISPLAY_ADDR],
2244                         xprt->address_strings[RPC_DISPLAY_PORT]);
2245
2246         status = xs_tcp_finish_connecting(xprt, sock);
2247         trace_rpc_socket_connect(xprt, sock, status);
2248         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2249                         xprt, -status, xprt_connected(xprt),
2250                         sock->sk->sk_state);
2251         switch (status) {
2252         case 0:
2253                 xs_set_srcport(transport, sock);
2254                 fallthrough;
2255         case -EINPROGRESS:
2256                 /* SYN_SENT! */
2257                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2258                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2259                 fallthrough;
2260         case -EALREADY:
2261                 goto out_unlock;
2262         case -EADDRNOTAVAIL:
2263                 /* Source port number is unavailable. Try a new one! */
2264                 transport->srcport = 0;
2265                 status = -EAGAIN;
2266                 break;
2267         case -EINVAL:
2268                 /* Happens, for instance, if the user specified a link
2269                  * local IPv6 address without a scope-id.
2270                  */
2271         case -ECONNREFUSED:
2272         case -ECONNRESET:
2273         case -ENETDOWN:
2274         case -ENETUNREACH:
2275         case -EHOSTUNREACH:
2276         case -EADDRINUSE:
2277         case -ENOBUFS:
2278                 break;
2279         default:
2280                 printk("%s: connect returned unhandled error %d\n",
2281                         __func__, status);
2282                 status = -EAGAIN;
2283         }
2284
2285         /* xs_tcp_force_close() wakes tasks with a fixed error code.
2286          * We need to wake them first to ensure the correct error code.
2287          */
2288         xprt_wake_pending_tasks(xprt, status);
2289         xs_tcp_force_close(xprt);
2290 out:
2291         xprt_clear_connecting(xprt);
2292 out_unlock:
2293         xprt_unlock_connect(xprt, transport);
2294 }
2295
2296 /**
2297  * xs_connect - connect a socket to a remote endpoint
2298  * @xprt: pointer to transport structure
2299  * @task: address of RPC task that manages state of connect request
2300  *
2301  * TCP: If the remote end dropped the connection, delay reconnecting.
2302  *
2303  * UDP socket connects are synchronous, but we use a work queue anyway
2304  * to guarantee that even unprivileged user processes can set up a
2305  * socket on a privileged port.
2306  *
2307  * If a UDP socket connect fails, the delay behavior here prevents
2308  * retry floods (hard mounts).
2309  */
2310 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2311 {
2312         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2313         unsigned long delay = 0;
2314
2315         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2316
2317         if (transport->sock != NULL && !xprt_connecting(xprt)) {
2318                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2319                                 "seconds\n",
2320                                 xprt, xprt->reestablish_timeout / HZ);
2321
2322                 /* Start by resetting any existing state */
2323                 xs_reset_transport(transport);
2324
2325                 delay = xprt_reconnect_delay(xprt);
2326                 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2327
2328         } else
2329                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2330
2331         queue_delayed_work(xprtiod_workqueue,
2332                         &transport->connect_worker,
2333                         delay);
2334 }
2335
2336 static void xs_wake_disconnect(struct sock_xprt *transport)
2337 {
2338         if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2339                 xs_tcp_force_close(&transport->xprt);
2340 }
2341
2342 static void xs_wake_write(struct sock_xprt *transport)
2343 {
2344         if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2345                 xprt_write_space(&transport->xprt);
2346 }
2347
2348 static void xs_wake_error(struct sock_xprt *transport)
2349 {
2350         int sockerr;
2351
2352         if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2353                 return;
2354         mutex_lock(&transport->recv_mutex);
2355         if (transport->sock == NULL)
2356                 goto out;
2357         if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2358                 goto out;
2359         sockerr = xchg(&transport->xprt_err, 0);
2360         if (sockerr < 0)
2361                 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2362 out:
2363         mutex_unlock(&transport->recv_mutex);
2364 }
2365
2366 static void xs_wake_pending(struct sock_xprt *transport)
2367 {
2368         if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2369                 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2370 }
2371
2372 static void xs_error_handle(struct work_struct *work)
2373 {
2374         struct sock_xprt *transport = container_of(work,
2375                         struct sock_xprt, error_worker);
2376
2377         xs_wake_disconnect(transport);
2378         xs_wake_write(transport);
2379         xs_wake_error(transport);
2380         xs_wake_pending(transport);
2381 }
2382
2383 /**
2384  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2385  * @xprt: rpc_xprt struct containing statistics
2386  * @seq: output file
2387  *
2388  */
2389 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2390 {
2391         long idle_time = 0;
2392
2393         if (xprt_connected(xprt))
2394                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2395
2396         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2397                         "%llu %llu %lu %llu %llu\n",
2398                         xprt->stat.bind_count,
2399                         xprt->stat.connect_count,
2400                         xprt->stat.connect_time / HZ,
2401                         idle_time,
2402                         xprt->stat.sends,
2403                         xprt->stat.recvs,
2404                         xprt->stat.bad_xids,
2405                         xprt->stat.req_u,
2406                         xprt->stat.bklog_u,
2407                         xprt->stat.max_slots,
2408                         xprt->stat.sending_u,
2409                         xprt->stat.pending_u);
2410 }
2411
2412 /**
2413  * xs_udp_print_stats - display UDP socket-specific stats
2414  * @xprt: rpc_xprt struct containing statistics
2415  * @seq: output file
2416  *
2417  */
2418 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2419 {
2420         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2421
2422         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2423                         "%lu %llu %llu\n",
2424                         transport->srcport,
2425                         xprt->stat.bind_count,
2426                         xprt->stat.sends,
2427                         xprt->stat.recvs,
2428                         xprt->stat.bad_xids,
2429                         xprt->stat.req_u,
2430                         xprt->stat.bklog_u,
2431                         xprt->stat.max_slots,
2432                         xprt->stat.sending_u,
2433                         xprt->stat.pending_u);
2434 }
2435
2436 /**
2437  * xs_tcp_print_stats - display TCP socket-specific stats
2438  * @xprt: rpc_xprt struct containing statistics
2439  * @seq: output file
2440  *
2441  */
2442 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2443 {
2444         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2445         long idle_time = 0;
2446
2447         if (xprt_connected(xprt))
2448                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2449
2450         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2451                         "%llu %llu %lu %llu %llu\n",
2452                         transport->srcport,
2453                         xprt->stat.bind_count,
2454                         xprt->stat.connect_count,
2455                         xprt->stat.connect_time / HZ,
2456                         idle_time,
2457                         xprt->stat.sends,
2458                         xprt->stat.recvs,
2459                         xprt->stat.bad_xids,
2460                         xprt->stat.req_u,
2461                         xprt->stat.bklog_u,
2462                         xprt->stat.max_slots,
2463                         xprt->stat.sending_u,
2464                         xprt->stat.pending_u);
2465 }
2466
2467 /*
2468  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2469  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2470  * to use the server side send routines.
2471  */
2472 static int bc_malloc(struct rpc_task *task)
2473 {
2474         struct rpc_rqst *rqst = task->tk_rqstp;
2475         size_t size = rqst->rq_callsize;
2476         struct page *page;
2477         struct rpc_buffer *buf;
2478
2479         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2480                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2481                           size);
2482                 return -EINVAL;
2483         }
2484
2485         page = alloc_page(GFP_KERNEL);
2486         if (!page)
2487                 return -ENOMEM;
2488
2489         buf = page_address(page);
2490         buf->len = PAGE_SIZE;
2491
2492         rqst->rq_buffer = buf->data;
2493         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2494         return 0;
2495 }
2496
2497 /*
2498  * Free the space allocated in the bc_alloc routine
2499  */
2500 static void bc_free(struct rpc_task *task)
2501 {
2502         void *buffer = task->tk_rqstp->rq_buffer;
2503         struct rpc_buffer *buf;
2504
2505         buf = container_of(buffer, struct rpc_buffer, data);
2506         free_page((unsigned long)buf);
2507 }
2508
2509 static int bc_sendto(struct rpc_rqst *req)
2510 {
2511         struct xdr_buf *xdr = &req->rq_snd_buf;
2512         struct sock_xprt *transport =
2513                         container_of(req->rq_xprt, struct sock_xprt, xprt);
2514         struct msghdr msg = {
2515                 .msg_flags      = 0,
2516         };
2517         rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2518                                          (u32)xdr->len);
2519         unsigned int sent = 0;
2520         int err;
2521
2522         req->rq_xtime = ktime_get();
2523         err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2524         xdr_free_bvec(xdr);
2525         if (err < 0 || sent != (xdr->len + sizeof(marker)))
2526                 return -EAGAIN;
2527         return sent;
2528 }
2529
2530 /**
2531  * bc_send_request - Send a backchannel Call on a TCP socket
2532  * @req: rpc_rqst containing Call message to be sent
2533  *
2534  * xpt_mutex ensures @rqstp's whole message is written to the socket
2535  * without interruption.
2536  *
2537  * Return values:
2538  *   %0 if the message was sent successfully
2539  *   %ENOTCONN if the message was not sent
2540  */
2541 static int bc_send_request(struct rpc_rqst *req)
2542 {
2543         struct svc_xprt *xprt;
2544         int len;
2545
2546         /*
2547          * Get the server socket associated with this callback xprt
2548          */
2549         xprt = req->rq_xprt->bc_xprt;
2550
2551         /*
2552          * Grab the mutex to serialize data as the connection is shared
2553          * with the fore channel
2554          */
2555         mutex_lock(&xprt->xpt_mutex);
2556         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2557                 len = -ENOTCONN;
2558         else
2559                 len = bc_sendto(req);
2560         mutex_unlock(&xprt->xpt_mutex);
2561
2562         if (len > 0)
2563                 len = 0;
2564
2565         return len;
2566 }
2567
2568 /*
2569  * The close routine. Since this is client initiated, we do nothing
2570  */
2571
2572 static void bc_close(struct rpc_xprt *xprt)
2573 {
2574         xprt_disconnect_done(xprt);
2575 }
2576
2577 /*
2578  * The xprt destroy routine. Again, because this connection is client
2579  * initiated, we do nothing
2580  */
2581
2582 static void bc_destroy(struct rpc_xprt *xprt)
2583 {
2584         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2585
2586         xs_xprt_free(xprt);
2587         module_put(THIS_MODULE);
2588 }
2589
2590 static const struct rpc_xprt_ops xs_local_ops = {
2591         .reserve_xprt           = xprt_reserve_xprt,
2592         .release_xprt           = xprt_release_xprt,
2593         .alloc_slot             = xprt_alloc_slot,
2594         .free_slot              = xprt_free_slot,
2595         .rpcbind                = xs_local_rpcbind,
2596         .set_port               = xs_local_set_port,
2597         .connect                = xs_local_connect,
2598         .buf_alloc              = rpc_malloc,
2599         .buf_free               = rpc_free,
2600         .prepare_request        = xs_stream_prepare_request,
2601         .send_request           = xs_local_send_request,
2602         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2603         .close                  = xs_close,
2604         .destroy                = xs_destroy,
2605         .print_stats            = xs_local_print_stats,
2606         .enable_swap            = xs_enable_swap,
2607         .disable_swap           = xs_disable_swap,
2608 };
2609
2610 static const struct rpc_xprt_ops xs_udp_ops = {
2611         .set_buffer_size        = xs_udp_set_buffer_size,
2612         .reserve_xprt           = xprt_reserve_xprt_cong,
2613         .release_xprt           = xprt_release_xprt_cong,
2614         .alloc_slot             = xprt_alloc_slot,
2615         .free_slot              = xprt_free_slot,
2616         .rpcbind                = rpcb_getport_async,
2617         .set_port               = xs_set_port,
2618         .connect                = xs_connect,
2619         .buf_alloc              = rpc_malloc,
2620         .buf_free               = rpc_free,
2621         .send_request           = xs_udp_send_request,
2622         .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2623         .timer                  = xs_udp_timer,
2624         .release_request        = xprt_release_rqst_cong,
2625         .close                  = xs_close,
2626         .destroy                = xs_destroy,
2627         .print_stats            = xs_udp_print_stats,
2628         .enable_swap            = xs_enable_swap,
2629         .disable_swap           = xs_disable_swap,
2630         .inject_disconnect      = xs_inject_disconnect,
2631 };
2632
2633 static const struct rpc_xprt_ops xs_tcp_ops = {
2634         .reserve_xprt           = xprt_reserve_xprt,
2635         .release_xprt           = xprt_release_xprt,
2636         .alloc_slot             = xprt_alloc_slot,
2637         .free_slot              = xprt_free_slot,
2638         .rpcbind                = rpcb_getport_async,
2639         .set_port               = xs_set_port,
2640         .connect                = xs_connect,
2641         .buf_alloc              = rpc_malloc,
2642         .buf_free               = rpc_free,
2643         .prepare_request        = xs_stream_prepare_request,
2644         .send_request           = xs_tcp_send_request,
2645         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2646         .close                  = xs_tcp_shutdown,
2647         .destroy                = xs_destroy,
2648         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2649         .print_stats            = xs_tcp_print_stats,
2650         .enable_swap            = xs_enable_swap,
2651         .disable_swap           = xs_disable_swap,
2652         .inject_disconnect      = xs_inject_disconnect,
2653 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2654         .bc_setup               = xprt_setup_bc,
2655         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2656         .bc_num_slots           = xprt_bc_max_slots,
2657         .bc_free_rqst           = xprt_free_bc_rqst,
2658         .bc_destroy             = xprt_destroy_bc,
2659 #endif
2660 };
2661
2662 /*
2663  * The rpc_xprt_ops for the server backchannel
2664  */
2665
2666 static const struct rpc_xprt_ops bc_tcp_ops = {
2667         .reserve_xprt           = xprt_reserve_xprt,
2668         .release_xprt           = xprt_release_xprt,
2669         .alloc_slot             = xprt_alloc_slot,
2670         .free_slot              = xprt_free_slot,
2671         .buf_alloc              = bc_malloc,
2672         .buf_free               = bc_free,
2673         .send_request           = bc_send_request,
2674         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2675         .close                  = bc_close,
2676         .destroy                = bc_destroy,
2677         .print_stats            = xs_tcp_print_stats,
2678         .enable_swap            = xs_enable_swap,
2679         .disable_swap           = xs_disable_swap,
2680         .inject_disconnect      = xs_inject_disconnect,
2681 };
2682
2683 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2684 {
2685         static const struct sockaddr_in sin = {
2686                 .sin_family             = AF_INET,
2687                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2688         };
2689         static const struct sockaddr_in6 sin6 = {
2690                 .sin6_family            = AF_INET6,
2691                 .sin6_addr              = IN6ADDR_ANY_INIT,
2692         };
2693
2694         switch (family) {
2695         case AF_LOCAL:
2696                 break;
2697         case AF_INET:
2698                 memcpy(sap, &sin, sizeof(sin));
2699                 break;
2700         case AF_INET6:
2701                 memcpy(sap, &sin6, sizeof(sin6));
2702                 break;
2703         default:
2704                 dprintk("RPC:       %s: Bad address family\n", __func__);
2705                 return -EAFNOSUPPORT;
2706         }
2707         return 0;
2708 }
2709
2710 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2711                                       unsigned int slot_table_size,
2712                                       unsigned int max_slot_table_size)
2713 {
2714         struct rpc_xprt *xprt;
2715         struct sock_xprt *new;
2716
2717         if (args->addrlen > sizeof(xprt->addr)) {
2718                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2719                 return ERR_PTR(-EBADF);
2720         }
2721
2722         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2723                         max_slot_table_size);
2724         if (xprt == NULL) {
2725                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2726                                 "rpc_xprt\n");
2727                 return ERR_PTR(-ENOMEM);
2728         }
2729
2730         new = container_of(xprt, struct sock_xprt, xprt);
2731         mutex_init(&new->recv_mutex);
2732         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2733         xprt->addrlen = args->addrlen;
2734         if (args->srcaddr)
2735                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2736         else {
2737                 int err;
2738                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2739                                         (struct sockaddr *)&new->srcaddr);
2740                 if (err != 0) {
2741                         xprt_free(xprt);
2742                         return ERR_PTR(err);
2743                 }
2744         }
2745
2746         return xprt;
2747 }
2748
2749 static const struct rpc_timeout xs_local_default_timeout = {
2750         .to_initval = 10 * HZ,
2751         .to_maxval = 10 * HZ,
2752         .to_retries = 2,
2753 };
2754
2755 /**
2756  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2757  * @args: rpc transport creation arguments
2758  *
2759  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2760  */
2761 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2762 {
2763         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2764         struct sock_xprt *transport;
2765         struct rpc_xprt *xprt;
2766         struct rpc_xprt *ret;
2767
2768         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2769                         xprt_max_tcp_slot_table_entries);
2770         if (IS_ERR(xprt))
2771                 return xprt;
2772         transport = container_of(xprt, struct sock_xprt, xprt);
2773
2774         xprt->prot = 0;
2775         xprt->xprt_class = &xs_local_transport;
2776         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2777
2778         xprt->bind_timeout = XS_BIND_TO;
2779         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2780         xprt->idle_timeout = XS_IDLE_DISC_TO;
2781
2782         xprt->ops = &xs_local_ops;
2783         xprt->timeout = &xs_local_default_timeout;
2784
2785         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2786         INIT_WORK(&transport->error_worker, xs_error_handle);
2787         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2788
2789         switch (sun->sun_family) {
2790         case AF_LOCAL:
2791                 if (sun->sun_path[0] != '/') {
2792                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2793                                         sun->sun_path);
2794                         ret = ERR_PTR(-EINVAL);
2795                         goto out_err;
2796                 }
2797                 xprt_set_bound(xprt);
2798                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2799                 ret = ERR_PTR(xs_local_setup_socket(transport));
2800                 if (ret)
2801                         goto out_err;
2802                 break;
2803         default:
2804                 ret = ERR_PTR(-EAFNOSUPPORT);
2805                 goto out_err;
2806         }
2807
2808         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2809                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2810
2811         if (try_module_get(THIS_MODULE))
2812                 return xprt;
2813         ret = ERR_PTR(-EINVAL);
2814 out_err:
2815         xs_xprt_free(xprt);
2816         return ret;
2817 }
2818
2819 static const struct rpc_timeout xs_udp_default_timeout = {
2820         .to_initval = 5 * HZ,
2821         .to_maxval = 30 * HZ,
2822         .to_increment = 5 * HZ,
2823         .to_retries = 5,
2824 };
2825
2826 /**
2827  * xs_setup_udp - Set up transport to use a UDP socket
2828  * @args: rpc transport creation arguments
2829  *
2830  */
2831 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2832 {
2833         struct sockaddr *addr = args->dstaddr;
2834         struct rpc_xprt *xprt;
2835         struct sock_xprt *transport;
2836         struct rpc_xprt *ret;
2837
2838         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2839                         xprt_udp_slot_table_entries);
2840         if (IS_ERR(xprt))
2841                 return xprt;
2842         transport = container_of(xprt, struct sock_xprt, xprt);
2843
2844         xprt->prot = IPPROTO_UDP;
2845         xprt->xprt_class = &xs_udp_transport;
2846         /* XXX: header size can vary due to auth type, IPv6, etc. */
2847         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2848
2849         xprt->bind_timeout = XS_BIND_TO;
2850         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2851         xprt->idle_timeout = XS_IDLE_DISC_TO;
2852
2853         xprt->ops = &xs_udp_ops;
2854
2855         xprt->timeout = &xs_udp_default_timeout;
2856
2857         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2858         INIT_WORK(&transport->error_worker, xs_error_handle);
2859         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2860
2861         switch (addr->sa_family) {
2862         case AF_INET:
2863                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2864                         xprt_set_bound(xprt);
2865
2866                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2867                 break;
2868         case AF_INET6:
2869                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2870                         xprt_set_bound(xprt);
2871
2872                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2873                 break;
2874         default:
2875                 ret = ERR_PTR(-EAFNOSUPPORT);
2876                 goto out_err;
2877         }
2878
2879         if (xprt_bound(xprt))
2880                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2881                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2882                                 xprt->address_strings[RPC_DISPLAY_PORT],
2883                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2884         else
2885                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2886                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2887                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2888
2889         if (try_module_get(THIS_MODULE))
2890                 return xprt;
2891         ret = ERR_PTR(-EINVAL);
2892 out_err:
2893         xs_xprt_free(xprt);
2894         return ret;
2895 }
2896
2897 static const struct rpc_timeout xs_tcp_default_timeout = {
2898         .to_initval = 60 * HZ,
2899         .to_maxval = 60 * HZ,
2900         .to_retries = 2,
2901 };
2902
2903 /**
2904  * xs_setup_tcp - Set up transport to use a TCP socket
2905  * @args: rpc transport creation arguments
2906  *
2907  */
2908 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2909 {
2910         struct sockaddr *addr = args->dstaddr;
2911         struct rpc_xprt *xprt;
2912         struct sock_xprt *transport;
2913         struct rpc_xprt *ret;
2914         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2915
2916         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2917                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2918
2919         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2920                         max_slot_table_size);
2921         if (IS_ERR(xprt))
2922                 return xprt;
2923         transport = container_of(xprt, struct sock_xprt, xprt);
2924
2925         xprt->prot = IPPROTO_TCP;
2926         xprt->xprt_class = &xs_tcp_transport;
2927         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2928
2929         xprt->bind_timeout = XS_BIND_TO;
2930         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2931         xprt->idle_timeout = XS_IDLE_DISC_TO;
2932
2933         xprt->ops = &xs_tcp_ops;
2934         xprt->timeout = &xs_tcp_default_timeout;
2935
2936         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2937         xprt->connect_timeout = xprt->timeout->to_initval *
2938                 (xprt->timeout->to_retries + 1);
2939
2940         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2941         INIT_WORK(&transport->error_worker, xs_error_handle);
2942         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2943
2944         switch (addr->sa_family) {
2945         case AF_INET:
2946                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2947                         xprt_set_bound(xprt);
2948
2949                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2950                 break;
2951         case AF_INET6:
2952                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2953                         xprt_set_bound(xprt);
2954
2955                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2956                 break;
2957         default:
2958                 ret = ERR_PTR(-EAFNOSUPPORT);
2959                 goto out_err;
2960         }
2961
2962         if (xprt_bound(xprt))
2963                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2964                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2965                                 xprt->address_strings[RPC_DISPLAY_PORT],
2966                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2967         else
2968                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2969                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2970                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2971
2972         if (try_module_get(THIS_MODULE))
2973                 return xprt;
2974         ret = ERR_PTR(-EINVAL);
2975 out_err:
2976         xs_xprt_free(xprt);
2977         return ret;
2978 }
2979
2980 /**
2981  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2982  * @args: rpc transport creation arguments
2983  *
2984  */
2985 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2986 {
2987         struct sockaddr *addr = args->dstaddr;
2988         struct rpc_xprt *xprt;
2989         struct sock_xprt *transport;
2990         struct svc_sock *bc_sock;
2991         struct rpc_xprt *ret;
2992
2993         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2994                         xprt_tcp_slot_table_entries);
2995         if (IS_ERR(xprt))
2996                 return xprt;
2997         transport = container_of(xprt, struct sock_xprt, xprt);
2998
2999         xprt->prot = IPPROTO_TCP;
3000         xprt->xprt_class = &xs_bc_tcp_transport;
3001         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3002         xprt->timeout = &xs_tcp_default_timeout;
3003
3004         /* backchannel */
3005         xprt_set_bound(xprt);
3006         xprt->bind_timeout = 0;
3007         xprt->reestablish_timeout = 0;
3008         xprt->idle_timeout = 0;
3009
3010         xprt->ops = &bc_tcp_ops;
3011
3012         switch (addr->sa_family) {
3013         case AF_INET:
3014                 xs_format_peer_addresses(xprt, "tcp",
3015                                          RPCBIND_NETID_TCP);
3016                 break;
3017         case AF_INET6:
3018                 xs_format_peer_addresses(xprt, "tcp",
3019                                    RPCBIND_NETID_TCP6);
3020                 break;
3021         default:
3022                 ret = ERR_PTR(-EAFNOSUPPORT);
3023                 goto out_err;
3024         }
3025
3026         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3027                         xprt->address_strings[RPC_DISPLAY_ADDR],
3028                         xprt->address_strings[RPC_DISPLAY_PORT],
3029                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3030
3031         /*
3032          * Once we've associated a backchannel xprt with a connection,
3033          * we want to keep it around as long as the connection lasts,
3034          * in case we need to start using it for a backchannel again;
3035          * this reference won't be dropped until bc_xprt is destroyed.
3036          */
3037         xprt_get(xprt);
3038         args->bc_xprt->xpt_bc_xprt = xprt;
3039         xprt->bc_xprt = args->bc_xprt;
3040         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3041         transport->sock = bc_sock->sk_sock;
3042         transport->inet = bc_sock->sk_sk;
3043
3044         /*
3045          * Since we don't want connections for the backchannel, we set
3046          * the xprt status to connected
3047          */
3048         xprt_set_connected(xprt);
3049
3050         if (try_module_get(THIS_MODULE))
3051                 return xprt;
3052
3053         args->bc_xprt->xpt_bc_xprt = NULL;
3054         args->bc_xprt->xpt_bc_xps = NULL;
3055         xprt_put(xprt);
3056         ret = ERR_PTR(-EINVAL);
3057 out_err:
3058         xs_xprt_free(xprt);
3059         return ret;
3060 }
3061
3062 static struct xprt_class        xs_local_transport = {
3063         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3064         .name           = "named UNIX socket",
3065         .owner          = THIS_MODULE,
3066         .ident          = XPRT_TRANSPORT_LOCAL,
3067         .setup          = xs_setup_local,
3068         .netid          = { "" },
3069 };
3070
3071 static struct xprt_class        xs_udp_transport = {
3072         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3073         .name           = "udp",
3074         .owner          = THIS_MODULE,
3075         .ident          = XPRT_TRANSPORT_UDP,
3076         .setup          = xs_setup_udp,
3077         .netid          = { "udp", "udp6", "" },
3078 };
3079
3080 static struct xprt_class        xs_tcp_transport = {
3081         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3082         .name           = "tcp",
3083         .owner          = THIS_MODULE,
3084         .ident          = XPRT_TRANSPORT_TCP,
3085         .setup          = xs_setup_tcp,
3086         .netid          = { "tcp", "tcp6", "" },
3087 };
3088
3089 static struct xprt_class        xs_bc_tcp_transport = {
3090         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3091         .name           = "tcp NFSv4.1 backchannel",
3092         .owner          = THIS_MODULE,
3093         .ident          = XPRT_TRANSPORT_BC_TCP,
3094         .setup          = xs_setup_bc_tcp,
3095         .netid          = { "" },
3096 };
3097
3098 /**
3099  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3100  *
3101  */
3102 int init_socket_xprt(void)
3103 {
3104         if (!sunrpc_table_header)
3105                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3106
3107         xprt_register_transport(&xs_local_transport);
3108         xprt_register_transport(&xs_udp_transport);
3109         xprt_register_transport(&xs_tcp_transport);
3110         xprt_register_transport(&xs_bc_tcp_transport);
3111
3112         return 0;
3113 }
3114
3115 /**
3116  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3117  *
3118  */
3119 void cleanup_socket_xprt(void)
3120 {
3121         if (sunrpc_table_header) {
3122                 unregister_sysctl_table(sunrpc_table_header);
3123                 sunrpc_table_header = NULL;
3124         }
3125
3126         xprt_unregister_transport(&xs_local_transport);
3127         xprt_unregister_transport(&xs_udp_transport);
3128         xprt_unregister_transport(&xs_tcp_transport);
3129         xprt_unregister_transport(&xs_bc_tcp_transport);
3130 }
3131
3132 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3133 {
3134         return param_set_uint_minmax(val, kp,
3135                         RPC_MIN_RESVPORT,
3136                         RPC_MAX_RESVPORT);
3137 }
3138
3139 static const struct kernel_param_ops param_ops_portnr = {
3140         .set = param_set_portnr,
3141         .get = param_get_uint,
3142 };
3143
3144 #define param_check_portnr(name, p) \
3145         __param_check(name, p, unsigned int);
3146
3147 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3148 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3149
3150 static int param_set_slot_table_size(const char *val,
3151                                      const struct kernel_param *kp)
3152 {
3153         return param_set_uint_minmax(val, kp,
3154                         RPC_MIN_SLOT_TABLE,
3155                         RPC_MAX_SLOT_TABLE);
3156 }
3157
3158 static const struct kernel_param_ops param_ops_slot_table_size = {
3159         .set = param_set_slot_table_size,
3160         .get = param_get_uint,
3161 };
3162
3163 #define param_check_slot_table_size(name, p) \
3164         __param_check(name, p, unsigned int);
3165
3166 static int param_set_max_slot_table_size(const char *val,
3167                                      const struct kernel_param *kp)
3168 {
3169         return param_set_uint_minmax(val, kp,
3170                         RPC_MIN_SLOT_TABLE,
3171                         RPC_MAX_SLOT_TABLE_LIMIT);
3172 }
3173
3174 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3175         .set = param_set_max_slot_table_size,
3176         .get = param_get_uint,
3177 };
3178
3179 #define param_check_max_slot_table_size(name, p) \
3180         __param_check(name, p, unsigned int);
3181
3182 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3183                    slot_table_size, 0644);
3184 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3185                    max_slot_table_size, 0644);
3186 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3187                    slot_table_size, 0644);