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         smp_mb__before_atomic();
1138         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1139         clear_bit(XPRT_CLOSING, &xprt->state);
1140         xs_sock_reset_state_flags(xprt);
1141         smp_mb__after_atomic();
1142 }
1143
1144 /**
1145  * xs_error_report - callback to handle TCP socket state errors
1146  * @sk: socket
1147  *
1148  * Note: we don't call sock_error() since there may be a rpc_task
1149  * using the socket, and so we don't want to clear sk->sk_err.
1150  */
1151 static void xs_error_report(struct sock *sk)
1152 {
1153         struct sock_xprt *transport;
1154         struct rpc_xprt *xprt;
1155
1156         read_lock_bh(&sk->sk_callback_lock);
1157         if (!(xprt = xprt_from_sock(sk)))
1158                 goto out;
1159
1160         transport = container_of(xprt, struct sock_xprt, xprt);
1161         transport->xprt_err = -sk->sk_err;
1162         if (transport->xprt_err == 0)
1163                 goto out;
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  out:
1172         read_unlock_bh(&sk->sk_callback_lock);
1173 }
1174
1175 static void xs_reset_transport(struct sock_xprt *transport)
1176 {
1177         struct socket *sock = transport->sock;
1178         struct sock *sk = transport->inet;
1179         struct rpc_xprt *xprt = &transport->xprt;
1180         struct file *filp = transport->file;
1181
1182         if (sk == NULL)
1183                 return;
1184
1185         if (atomic_read(&transport->xprt.swapper))
1186                 sk_clear_memalloc(sk);
1187
1188         kernel_sock_shutdown(sock, SHUT_RDWR);
1189
1190         mutex_lock(&transport->recv_mutex);
1191         write_lock_bh(&sk->sk_callback_lock);
1192         transport->inet = NULL;
1193         transport->sock = NULL;
1194         transport->file = NULL;
1195
1196         sk->sk_user_data = NULL;
1197
1198         xs_restore_old_callbacks(transport, sk);
1199         xprt_clear_connected(xprt);
1200         write_unlock_bh(&sk->sk_callback_lock);
1201         xs_sock_reset_connection_flags(xprt);
1202         /* Reset stream record info */
1203         xs_stream_reset_connect(transport);
1204         mutex_unlock(&transport->recv_mutex);
1205
1206         trace_rpc_socket_close(xprt, sock);
1207         fput(filp);
1208
1209         xprt_disconnect_done(xprt);
1210 }
1211
1212 /**
1213  * xs_close - close a socket
1214  * @xprt: transport
1215  *
1216  * This is used when all requests are complete; ie, no DRC state remains
1217  * on the server we want to save.
1218  *
1219  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
1220  * xs_reset_transport() zeroing the socket from underneath a writer.
1221  */
1222 static void xs_close(struct rpc_xprt *xprt)
1223 {
1224         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1225
1226         dprintk("RPC:       xs_close xprt %p\n", xprt);
1227
1228         xs_reset_transport(transport);
1229         xprt->reestablish_timeout = 0;
1230 }
1231
1232 static void xs_inject_disconnect(struct rpc_xprt *xprt)
1233 {
1234         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
1235                 xprt);
1236         xprt_disconnect_done(xprt);
1237 }
1238
1239 static void xs_xprt_free(struct rpc_xprt *xprt)
1240 {
1241         xs_free_peer_addresses(xprt);
1242         xprt_free(xprt);
1243 }
1244
1245 /**
1246  * xs_destroy - prepare to shutdown a transport
1247  * @xprt: doomed transport
1248  *
1249  */
1250 static void xs_destroy(struct rpc_xprt *xprt)
1251 {
1252         struct sock_xprt *transport = container_of(xprt,
1253                         struct sock_xprt, xprt);
1254         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
1255
1256         cancel_delayed_work_sync(&transport->connect_worker);
1257         xs_close(xprt);
1258         cancel_work_sync(&transport->recv_worker);
1259         cancel_work_sync(&transport->error_worker);
1260         xs_xprt_free(xprt);
1261         module_put(THIS_MODULE);
1262 }
1263
1264 /**
1265  * xs_udp_data_read_skb - receive callback for UDP sockets
1266  * @xprt: transport
1267  * @sk: socket
1268  * @skb: skbuff
1269  *
1270  */
1271 static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
1272                 struct sock *sk,
1273                 struct sk_buff *skb)
1274 {
1275         struct rpc_task *task;
1276         struct rpc_rqst *rovr;
1277         int repsize, copied;
1278         u32 _xid;
1279         __be32 *xp;
1280
1281         repsize = skb->len;
1282         if (repsize < 4) {
1283                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1284                 return;
1285         }
1286
1287         /* Copy the XID from the skb... */
1288         xp = skb_header_pointer(skb, 0, sizeof(_xid), &_xid);
1289         if (xp == NULL)
1290                 return;
1291
1292         /* Look up and lock the request corresponding to the given XID */
1293         spin_lock(&xprt->queue_lock);
1294         rovr = xprt_lookup_rqst(xprt, *xp);
1295         if (!rovr)
1296                 goto out_unlock;
1297         xprt_pin_rqst(rovr);
1298         xprt_update_rtt(rovr->rq_task);
1299         spin_unlock(&xprt->queue_lock);
1300         task = rovr->rq_task;
1301
1302         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1303                 copied = repsize;
1304
1305         /* Suck it into the iovec, verify checksum if not done by hw. */
1306         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1307                 spin_lock(&xprt->queue_lock);
1308                 __UDPX_INC_STATS(sk, UDP_MIB_INERRORS);
1309                 goto out_unpin;
1310         }
1311
1312
1313         spin_lock(&xprt->transport_lock);
1314         xprt_adjust_cwnd(xprt, task, copied);
1315         spin_unlock(&xprt->transport_lock);
1316         spin_lock(&xprt->queue_lock);
1317         xprt_complete_rqst(task, copied);
1318         __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
1319 out_unpin:
1320         xprt_unpin_rqst(rovr);
1321  out_unlock:
1322         spin_unlock(&xprt->queue_lock);
1323 }
1324
1325 static void xs_udp_data_receive(struct sock_xprt *transport)
1326 {
1327         struct sk_buff *skb;
1328         struct sock *sk;
1329         int err;
1330
1331         mutex_lock(&transport->recv_mutex);
1332         sk = transport->inet;
1333         if (sk == NULL)
1334                 goto out;
1335         for (;;) {
1336                 skb = skb_recv_udp(sk, 0, 1, &err);
1337                 if (skb == NULL)
1338                         break;
1339                 xs_udp_data_read_skb(&transport->xprt, sk, skb);
1340                 consume_skb(skb);
1341                 cond_resched();
1342         }
1343         xs_poll_check_readable(transport);
1344 out:
1345         mutex_unlock(&transport->recv_mutex);
1346 }
1347
1348 static void xs_udp_data_receive_workfn(struct work_struct *work)
1349 {
1350         struct sock_xprt *transport =
1351                 container_of(work, struct sock_xprt, recv_worker);
1352         unsigned int pflags = memalloc_nofs_save();
1353
1354         xs_udp_data_receive(transport);
1355         memalloc_nofs_restore(pflags);
1356 }
1357
1358 /**
1359  * xs_data_ready - "data ready" callback for UDP sockets
1360  * @sk: socket with data to read
1361  *
1362  */
1363 static void xs_data_ready(struct sock *sk)
1364 {
1365         struct rpc_xprt *xprt;
1366
1367         read_lock_bh(&sk->sk_callback_lock);
1368         dprintk("RPC:       xs_data_ready...\n");
1369         xprt = xprt_from_sock(sk);
1370         if (xprt != NULL) {
1371                 struct sock_xprt *transport = container_of(xprt,
1372                                 struct sock_xprt, xprt);
1373                 transport->old_data_ready(sk);
1374                 /* Any data means we had a useful conversation, so
1375                  * then we don't need to delay the next reconnect
1376                  */
1377                 if (xprt->reestablish_timeout)
1378                         xprt->reestablish_timeout = 0;
1379                 if (!test_and_set_bit(XPRT_SOCK_DATA_READY, &transport->sock_state))
1380                         queue_work(xprtiod_workqueue, &transport->recv_worker);
1381         }
1382         read_unlock_bh(&sk->sk_callback_lock);
1383 }
1384
1385 /*
1386  * Helper function to force a TCP close if the server is sending
1387  * junk and/or it has put us in CLOSE_WAIT
1388  */
1389 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1390 {
1391         xprt_force_disconnect(xprt);
1392 }
1393
1394 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1395 static size_t xs_tcp_bc_maxpayload(struct rpc_xprt *xprt)
1396 {
1397         return PAGE_SIZE;
1398 }
1399 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1400
1401 /**
1402  * xs_tcp_state_change - callback to handle TCP socket state changes
1403  * @sk: socket whose state has changed
1404  *
1405  */
1406 static void xs_tcp_state_change(struct sock *sk)
1407 {
1408         struct rpc_xprt *xprt;
1409         struct sock_xprt *transport;
1410
1411         read_lock_bh(&sk->sk_callback_lock);
1412         if (!(xprt = xprt_from_sock(sk)))
1413                 goto out;
1414         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1415         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1416                         sk->sk_state, xprt_connected(xprt),
1417                         sock_flag(sk, SOCK_DEAD),
1418                         sock_flag(sk, SOCK_ZAPPED),
1419                         sk->sk_shutdown);
1420
1421         transport = container_of(xprt, struct sock_xprt, xprt);
1422         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1423         switch (sk->sk_state) {
1424         case TCP_ESTABLISHED:
1425                 if (!xprt_test_and_set_connected(xprt)) {
1426                         xprt->connect_cookie++;
1427                         clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
1428                         xprt_clear_connecting(xprt);
1429
1430                         xprt->stat.connect_count++;
1431                         xprt->stat.connect_time += (long)jiffies -
1432                                                    xprt->stat.connect_start;
1433                         xs_run_error_worker(transport, XPRT_SOCK_WAKE_PENDING);
1434                 }
1435                 break;
1436         case TCP_FIN_WAIT1:
1437                 /* The client initiated a shutdown of the socket */
1438                 xprt->connect_cookie++;
1439                 xprt->reestablish_timeout = 0;
1440                 set_bit(XPRT_CLOSING, &xprt->state);
1441                 smp_mb__before_atomic();
1442                 clear_bit(XPRT_CONNECTED, &xprt->state);
1443                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1444                 smp_mb__after_atomic();
1445                 break;
1446         case TCP_CLOSE_WAIT:
1447                 /* The server initiated a shutdown of the socket */
1448                 xprt->connect_cookie++;
1449                 clear_bit(XPRT_CONNECTED, &xprt->state);
1450                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1451                 fallthrough;
1452         case TCP_CLOSING:
1453                 /*
1454                  * If the server closed down the connection, make sure that
1455                  * we back off before reconnecting
1456                  */
1457                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1458                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1459                 break;
1460         case TCP_LAST_ACK:
1461                 set_bit(XPRT_CLOSING, &xprt->state);
1462                 smp_mb__before_atomic();
1463                 clear_bit(XPRT_CONNECTED, &xprt->state);
1464                 smp_mb__after_atomic();
1465                 break;
1466         case TCP_CLOSE:
1467                 if (test_and_clear_bit(XPRT_SOCK_CONNECTING,
1468                                         &transport->sock_state))
1469                         xprt_clear_connecting(xprt);
1470                 clear_bit(XPRT_CLOSING, &xprt->state);
1471                 /* Trigger the socket release */
1472                 xs_run_error_worker(transport, XPRT_SOCK_WAKE_DISCONNECT);
1473         }
1474  out:
1475         read_unlock_bh(&sk->sk_callback_lock);
1476 }
1477
1478 static void xs_write_space(struct sock *sk)
1479 {
1480         struct socket_wq *wq;
1481         struct sock_xprt *transport;
1482         struct rpc_xprt *xprt;
1483
1484         if (!sk->sk_socket)
1485                 return;
1486         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1487
1488         if (unlikely(!(xprt = xprt_from_sock(sk))))
1489                 return;
1490         transport = container_of(xprt, struct sock_xprt, xprt);
1491         rcu_read_lock();
1492         wq = rcu_dereference(sk->sk_wq);
1493         if (!wq || test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags) == 0)
1494                 goto out;
1495
1496         xs_run_error_worker(transport, XPRT_SOCK_WAKE_WRITE);
1497         sk->sk_write_pending--;
1498 out:
1499         rcu_read_unlock();
1500 }
1501
1502 /**
1503  * xs_udp_write_space - callback invoked when socket buffer space
1504  *                             becomes available
1505  * @sk: socket whose state has changed
1506  *
1507  * Called when more output buffer space is available for this socket.
1508  * We try not to wake our writers until they can make "significant"
1509  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1510  * with a bunch of small requests.
1511  */
1512 static void xs_udp_write_space(struct sock *sk)
1513 {
1514         read_lock_bh(&sk->sk_callback_lock);
1515
1516         /* from net/core/sock.c:sock_def_write_space */
1517         if (sock_writeable(sk))
1518                 xs_write_space(sk);
1519
1520         read_unlock_bh(&sk->sk_callback_lock);
1521 }
1522
1523 /**
1524  * xs_tcp_write_space - callback invoked when socket buffer space
1525  *                             becomes available
1526  * @sk: socket whose state has changed
1527  *
1528  * Called when more output buffer space is available for this socket.
1529  * We try not to wake our writers until they can make "significant"
1530  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1531  * with a bunch of small requests.
1532  */
1533 static void xs_tcp_write_space(struct sock *sk)
1534 {
1535         read_lock_bh(&sk->sk_callback_lock);
1536
1537         /* from net/core/stream.c:sk_stream_write_space */
1538         if (sk_stream_is_writeable(sk))
1539                 xs_write_space(sk);
1540
1541         read_unlock_bh(&sk->sk_callback_lock);
1542 }
1543
1544 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1545 {
1546         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1547         struct sock *sk = transport->inet;
1548
1549         if (transport->rcvsize) {
1550                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1551                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1552         }
1553         if (transport->sndsize) {
1554                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1555                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1556                 sk->sk_write_space(sk);
1557         }
1558 }
1559
1560 /**
1561  * xs_udp_set_buffer_size - set send and receive limits
1562  * @xprt: generic transport
1563  * @sndsize: requested size of send buffer, in bytes
1564  * @rcvsize: requested size of receive buffer, in bytes
1565  *
1566  * Set socket send and receive buffer size limits.
1567  */
1568 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1569 {
1570         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1571
1572         transport->sndsize = 0;
1573         if (sndsize)
1574                 transport->sndsize = sndsize + 1024;
1575         transport->rcvsize = 0;
1576         if (rcvsize)
1577                 transport->rcvsize = rcvsize + 1024;
1578
1579         xs_udp_do_set_buffer_size(xprt);
1580 }
1581
1582 /**
1583  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1584  * @xprt: controlling transport
1585  * @task: task that timed out
1586  *
1587  * Adjust the congestion window after a retransmit timeout has occurred.
1588  */
1589 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1590 {
1591         spin_lock(&xprt->transport_lock);
1592         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1593         spin_unlock(&xprt->transport_lock);
1594 }
1595
1596 static int xs_get_random_port(void)
1597 {
1598         unsigned short min = xprt_min_resvport, max = xprt_max_resvport;
1599         unsigned short range;
1600         unsigned short rand;
1601
1602         if (max < min)
1603                 return -EADDRINUSE;
1604         range = max - min + 1;
1605         rand = (unsigned short) prandom_u32() % range;
1606         return rand + min;
1607 }
1608
1609 static unsigned short xs_sock_getport(struct socket *sock)
1610 {
1611         struct sockaddr_storage buf;
1612         unsigned short port = 0;
1613
1614         if (kernel_getsockname(sock, (struct sockaddr *)&buf) < 0)
1615                 goto out;
1616         switch (buf.ss_family) {
1617         case AF_INET6:
1618                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1619                 break;
1620         case AF_INET:
1621                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1622         }
1623 out:
1624         return port;
1625 }
1626
1627 /**
1628  * xs_set_port - reset the port number in the remote endpoint address
1629  * @xprt: generic transport
1630  * @port: new port number
1631  *
1632  */
1633 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1634 {
1635         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1636
1637         rpc_set_port(xs_addr(xprt), port);
1638         xs_update_peer_port(xprt);
1639 }
1640
1641 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1642 {
1643         if (transport->srcport == 0 && transport->xprt.reuseport)
1644                 transport->srcport = xs_sock_getport(sock);
1645 }
1646
1647 static int xs_get_srcport(struct sock_xprt *transport)
1648 {
1649         int port = transport->srcport;
1650
1651         if (port == 0 && transport->xprt.resvport)
1652                 port = xs_get_random_port();
1653         return port;
1654 }
1655
1656 unsigned short get_srcport(struct rpc_xprt *xprt)
1657 {
1658         struct sock_xprt *sock = container_of(xprt, struct sock_xprt, xprt);
1659         return sock->srcport;
1660 }
1661 EXPORT_SYMBOL(get_srcport);
1662
1663 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1664 {
1665         if (transport->srcport != 0)
1666                 transport->srcport = 0;
1667         if (!transport->xprt.resvport)
1668                 return 0;
1669         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1670                 return xprt_max_resvport;
1671         return --port;
1672 }
1673 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1674 {
1675         struct sockaddr_storage myaddr;
1676         int err, nloop = 0;
1677         int port = xs_get_srcport(transport);
1678         unsigned short last;
1679
1680         /*
1681          * If we are asking for any ephemeral port (i.e. port == 0 &&
1682          * transport->xprt.resvport == 0), don't bind.  Let the local
1683          * port selection happen implicitly when the socket is used
1684          * (for example at connect time).
1685          *
1686          * This ensures that we can continue to establish TCP
1687          * connections even when all local ephemeral ports are already
1688          * a part of some TCP connection.  This makes no difference
1689          * for UDP sockets, but also doesn't harm them.
1690          *
1691          * If we're asking for any reserved port (i.e. port == 0 &&
1692          * transport->xprt.resvport == 1) xs_get_srcport above will
1693          * ensure that port is non-zero and we will bind as needed.
1694          */
1695         if (port <= 0)
1696                 return port;
1697
1698         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1699         do {
1700                 rpc_set_port((struct sockaddr *)&myaddr, port);
1701                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1702                                 transport->xprt.addrlen);
1703                 if (err == 0) {
1704                         transport->srcport = port;
1705                         break;
1706                 }
1707                 last = port;
1708                 port = xs_next_srcport(transport, port);
1709                 if (port > last)
1710                         nloop++;
1711         } while (err == -EADDRINUSE && nloop != 2);
1712
1713         if (myaddr.ss_family == AF_INET)
1714                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1715                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1716                                 port, err ? "failed" : "ok", err);
1717         else
1718                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1719                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1720                                 port, err ? "failed" : "ok", err);
1721         return err;
1722 }
1723
1724 /*
1725  * We don't support autobind on AF_LOCAL sockets
1726  */
1727 static void xs_local_rpcbind(struct rpc_task *task)
1728 {
1729         xprt_set_bound(task->tk_xprt);
1730 }
1731
1732 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1733 {
1734 }
1735
1736 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1737 static struct lock_class_key xs_key[2];
1738 static struct lock_class_key xs_slock_key[2];
1739
1740 static inline void xs_reclassify_socketu(struct socket *sock)
1741 {
1742         struct sock *sk = sock->sk;
1743
1744         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1745                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1746 }
1747
1748 static inline void xs_reclassify_socket4(struct socket *sock)
1749 {
1750         struct sock *sk = sock->sk;
1751
1752         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1753                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1754 }
1755
1756 static inline void xs_reclassify_socket6(struct socket *sock)
1757 {
1758         struct sock *sk = sock->sk;
1759
1760         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1761                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1762 }
1763
1764 static inline void xs_reclassify_socket(int family, struct socket *sock)
1765 {
1766         if (WARN_ON_ONCE(!sock_allow_reclassification(sock->sk)))
1767                 return;
1768
1769         switch (family) {
1770         case AF_LOCAL:
1771                 xs_reclassify_socketu(sock);
1772                 break;
1773         case AF_INET:
1774                 xs_reclassify_socket4(sock);
1775                 break;
1776         case AF_INET6:
1777                 xs_reclassify_socket6(sock);
1778                 break;
1779         }
1780 }
1781 #else
1782 static inline void xs_reclassify_socket(int family, struct socket *sock)
1783 {
1784 }
1785 #endif
1786
1787 static void xs_dummy_setup_socket(struct work_struct *work)
1788 {
1789 }
1790
1791 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1792                 struct sock_xprt *transport, int family, int type,
1793                 int protocol, bool reuseport)
1794 {
1795         struct file *filp;
1796         struct socket *sock;
1797         int err;
1798
1799         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1800         if (err < 0) {
1801                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1802                                 protocol, -err);
1803                 goto out;
1804         }
1805         xs_reclassify_socket(family, sock);
1806
1807         if (reuseport)
1808                 sock_set_reuseport(sock->sk);
1809
1810         err = xs_bind(transport, sock);
1811         if (err) {
1812                 sock_release(sock);
1813                 goto out;
1814         }
1815
1816         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1817         if (IS_ERR(filp))
1818                 return ERR_CAST(filp);
1819         transport->file = filp;
1820
1821         return sock;
1822 out:
1823         return ERR_PTR(err);
1824 }
1825
1826 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1827                                       struct socket *sock)
1828 {
1829         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1830                                                                         xprt);
1831
1832         if (!transport->inet) {
1833                 struct sock *sk = sock->sk;
1834
1835                 write_lock_bh(&sk->sk_callback_lock);
1836
1837                 xs_save_old_callbacks(transport, sk);
1838
1839                 sk->sk_user_data = xprt;
1840                 sk->sk_data_ready = xs_data_ready;
1841                 sk->sk_write_space = xs_udp_write_space;
1842                 sock_set_flag(sk, SOCK_FASYNC);
1843                 sk->sk_error_report = xs_error_report;
1844
1845                 xprt_clear_connected(xprt);
1846
1847                 /* Reset to new socket */
1848                 transport->sock = sock;
1849                 transport->inet = sk;
1850
1851                 write_unlock_bh(&sk->sk_callback_lock);
1852         }
1853
1854         xs_stream_start_connect(transport);
1855
1856         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1857 }
1858
1859 /**
1860  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1861  * @transport: socket transport to connect
1862  */
1863 static int xs_local_setup_socket(struct sock_xprt *transport)
1864 {
1865         struct rpc_xprt *xprt = &transport->xprt;
1866         struct file *filp;
1867         struct socket *sock;
1868         int status;
1869
1870         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1871                                         SOCK_STREAM, 0, &sock, 1);
1872         if (status < 0) {
1873                 dprintk("RPC:       can't create AF_LOCAL "
1874                         "transport socket (%d).\n", -status);
1875                 goto out;
1876         }
1877         xs_reclassify_socket(AF_LOCAL, sock);
1878
1879         filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
1880         if (IS_ERR(filp)) {
1881                 status = PTR_ERR(filp);
1882                 goto out;
1883         }
1884         transport->file = filp;
1885
1886         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1887                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1888
1889         status = xs_local_finish_connecting(xprt, sock);
1890         trace_rpc_socket_connect(xprt, sock, status);
1891         switch (status) {
1892         case 0:
1893                 dprintk("RPC:       xprt %p connected to %s\n",
1894                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1895                 xprt->stat.connect_count++;
1896                 xprt->stat.connect_time += (long)jiffies -
1897                                            xprt->stat.connect_start;
1898                 xprt_set_connected(xprt);
1899                 break;
1900         case -ENOBUFS:
1901                 break;
1902         case -ENOENT:
1903                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1904                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1905                 break;
1906         case -ECONNREFUSED:
1907                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1908                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1909                 break;
1910         default:
1911                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1912                                 __func__, -status,
1913                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1914         }
1915
1916 out:
1917         xprt_clear_connecting(xprt);
1918         xprt_wake_pending_tasks(xprt, status);
1919         return status;
1920 }
1921
1922 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1923 {
1924         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1925         int ret;
1926
1927          if (RPC_IS_ASYNC(task)) {
1928                 /*
1929                  * We want the AF_LOCAL connect to be resolved in the
1930                  * filesystem namespace of the process making the rpc
1931                  * call.  Thus we connect synchronously.
1932                  *
1933                  * If we want to support asynchronous AF_LOCAL calls,
1934                  * we'll need to figure out how to pass a namespace to
1935                  * connect.
1936                  */
1937                 task->tk_rpc_status = -ENOTCONN;
1938                 rpc_exit(task, -ENOTCONN);
1939                 return;
1940         }
1941         ret = xs_local_setup_socket(transport);
1942         if (ret && !RPC_IS_SOFTCONN(task))
1943                 msleep_interruptible(15000);
1944 }
1945
1946 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1947 /*
1948  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1949  * know that we have exclusive access to the socket), to guard against
1950  * races with xs_reset_transport.
1951  */
1952 static void xs_set_memalloc(struct rpc_xprt *xprt)
1953 {
1954         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1955                         xprt);
1956
1957         /*
1958          * If there's no sock, then we have nothing to set. The
1959          * reconnecting process will get it for us.
1960          */
1961         if (!transport->inet)
1962                 return;
1963         if (atomic_read(&xprt->swapper))
1964                 sk_set_memalloc(transport->inet);
1965 }
1966
1967 /**
1968  * xs_enable_swap - Tag this transport as being used for swap.
1969  * @xprt: transport to tag
1970  *
1971  * Take a reference to this transport on behalf of the rpc_clnt, and
1972  * optionally mark it for swapping if it wasn't already.
1973  */
1974 static int
1975 xs_enable_swap(struct rpc_xprt *xprt)
1976 {
1977         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1978
1979         if (atomic_inc_return(&xprt->swapper) != 1)
1980                 return 0;
1981         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1982                 return -ERESTARTSYS;
1983         if (xs->inet)
1984                 sk_set_memalloc(xs->inet);
1985         xprt_release_xprt(xprt, NULL);
1986         return 0;
1987 }
1988
1989 /**
1990  * xs_disable_swap - Untag this transport as being used for swap.
1991  * @xprt: transport to tag
1992  *
1993  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
1994  * swapper refcount goes to 0, untag the socket as a memalloc socket.
1995  */
1996 static void
1997 xs_disable_swap(struct rpc_xprt *xprt)
1998 {
1999         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2000
2001         if (!atomic_dec_and_test(&xprt->swapper))
2002                 return;
2003         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2004                 return;
2005         if (xs->inet)
2006                 sk_clear_memalloc(xs->inet);
2007         xprt_release_xprt(xprt, NULL);
2008 }
2009 #else
2010 static void xs_set_memalloc(struct rpc_xprt *xprt)
2011 {
2012 }
2013
2014 static int
2015 xs_enable_swap(struct rpc_xprt *xprt)
2016 {
2017         return -EINVAL;
2018 }
2019
2020 static void
2021 xs_disable_swap(struct rpc_xprt *xprt)
2022 {
2023 }
2024 #endif
2025
2026 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2027 {
2028         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2029
2030         if (!transport->inet) {
2031                 struct sock *sk = sock->sk;
2032
2033                 write_lock_bh(&sk->sk_callback_lock);
2034
2035                 xs_save_old_callbacks(transport, sk);
2036
2037                 sk->sk_user_data = xprt;
2038                 sk->sk_data_ready = xs_data_ready;
2039                 sk->sk_write_space = xs_udp_write_space;
2040                 sock_set_flag(sk, SOCK_FASYNC);
2041
2042                 xprt_set_connected(xprt);
2043
2044                 /* Reset to new socket */
2045                 transport->sock = sock;
2046                 transport->inet = sk;
2047
2048                 xs_set_memalloc(xprt);
2049
2050                 write_unlock_bh(&sk->sk_callback_lock);
2051         }
2052         xs_udp_do_set_buffer_size(xprt);
2053
2054         xprt->stat.connect_start = jiffies;
2055 }
2056
2057 static void xs_udp_setup_socket(struct work_struct *work)
2058 {
2059         struct sock_xprt *transport =
2060                 container_of(work, struct sock_xprt, connect_worker.work);
2061         struct rpc_xprt *xprt = &transport->xprt;
2062         struct socket *sock;
2063         int status = -EIO;
2064
2065         sock = xs_create_sock(xprt, transport,
2066                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2067                         IPPROTO_UDP, false);
2068         if (IS_ERR(sock))
2069                 goto out;
2070
2071         dprintk("RPC:       worker connecting xprt %p via %s to "
2072                                 "%s (port %s)\n", xprt,
2073                         xprt->address_strings[RPC_DISPLAY_PROTO],
2074                         xprt->address_strings[RPC_DISPLAY_ADDR],
2075                         xprt->address_strings[RPC_DISPLAY_PORT]);
2076
2077         xs_udp_finish_connecting(xprt, sock);
2078         trace_rpc_socket_connect(xprt, sock, 0);
2079         status = 0;
2080 out:
2081         xprt_clear_connecting(xprt);
2082         xprt_unlock_connect(xprt, transport);
2083         xprt_wake_pending_tasks(xprt, status);
2084 }
2085
2086 /**
2087  * xs_tcp_shutdown - gracefully shut down a TCP socket
2088  * @xprt: transport
2089  *
2090  * Initiates a graceful shutdown of the TCP socket by calling the
2091  * equivalent of shutdown(SHUT_RDWR);
2092  */
2093 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2094 {
2095         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2096         struct socket *sock = transport->sock;
2097         int skst = transport->inet ? transport->inet->sk_state : TCP_CLOSE;
2098
2099         if (sock == NULL)
2100                 return;
2101         switch (skst) {
2102         default:
2103                 kernel_sock_shutdown(sock, SHUT_RDWR);
2104                 trace_rpc_socket_shutdown(xprt, sock);
2105                 break;
2106         case TCP_CLOSE:
2107         case TCP_TIME_WAIT:
2108                 xs_reset_transport(transport);
2109         }
2110 }
2111
2112 static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
2113                 struct socket *sock)
2114 {
2115         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2116         unsigned int keepidle;
2117         unsigned int keepcnt;
2118         unsigned int timeo;
2119
2120         spin_lock(&xprt->transport_lock);
2121         keepidle = DIV_ROUND_UP(xprt->timeout->to_initval, HZ);
2122         keepcnt = xprt->timeout->to_retries + 1;
2123         timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2124                 (xprt->timeout->to_retries + 1);
2125         clear_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2126         spin_unlock(&xprt->transport_lock);
2127
2128         /* TCP Keepalive options */
2129         sock_set_keepalive(sock->sk);
2130         tcp_sock_set_keepidle(sock->sk, keepidle);
2131         tcp_sock_set_keepintvl(sock->sk, keepidle);
2132         tcp_sock_set_keepcnt(sock->sk, keepcnt);
2133
2134         /* TCP user timeout (see RFC5482) */
2135         tcp_sock_set_user_timeout(sock->sk, timeo);
2136 }
2137
2138 static void xs_tcp_set_connect_timeout(struct rpc_xprt *xprt,
2139                 unsigned long connect_timeout,
2140                 unsigned long reconnect_timeout)
2141 {
2142         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2143         struct rpc_timeout to;
2144         unsigned long initval;
2145
2146         spin_lock(&xprt->transport_lock);
2147         if (reconnect_timeout < xprt->max_reconnect_timeout)
2148                 xprt->max_reconnect_timeout = reconnect_timeout;
2149         if (connect_timeout < xprt->connect_timeout) {
2150                 memcpy(&to, xprt->timeout, sizeof(to));
2151                 initval = DIV_ROUND_UP(connect_timeout, to.to_retries + 1);
2152                 /* Arbitrary lower limit */
2153                 if (initval <  XS_TCP_INIT_REEST_TO << 1)
2154                         initval = XS_TCP_INIT_REEST_TO << 1;
2155                 to.to_initval = initval;
2156                 to.to_maxval = initval;
2157                 memcpy(&transport->tcp_timeout, &to,
2158                                 sizeof(transport->tcp_timeout));
2159                 xprt->timeout = &transport->tcp_timeout;
2160                 xprt->connect_timeout = connect_timeout;
2161         }
2162         set_bit(XPRT_SOCK_UPD_TIMEOUT, &transport->sock_state);
2163         spin_unlock(&xprt->transport_lock);
2164 }
2165
2166 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2167 {
2168         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2169         int ret = -ENOTCONN;
2170
2171         if (!transport->inet) {
2172                 struct sock *sk = sock->sk;
2173
2174                 /* Avoid temporary address, they are bad for long-lived
2175                  * connections such as NFS mounts.
2176                  * RFC4941, section 3.6 suggests that:
2177                  *    Individual applications, which have specific
2178                  *    knowledge about the normal duration of connections,
2179                  *    MAY override this as appropriate.
2180                  */
2181                 if (xs_addr(xprt)->sa_family == PF_INET6) {
2182                         ip6_sock_set_addr_preferences(sk,
2183                                 IPV6_PREFER_SRC_PUBLIC);
2184                 }
2185
2186                 xs_tcp_set_socket_timeouts(xprt, sock);
2187                 tcp_sock_set_nodelay(sk);
2188
2189                 write_lock_bh(&sk->sk_callback_lock);
2190
2191                 xs_save_old_callbacks(transport, sk);
2192
2193                 sk->sk_user_data = xprt;
2194                 sk->sk_data_ready = xs_data_ready;
2195                 sk->sk_state_change = xs_tcp_state_change;
2196                 sk->sk_write_space = xs_tcp_write_space;
2197                 sock_set_flag(sk, SOCK_FASYNC);
2198                 sk->sk_error_report = xs_error_report;
2199
2200                 /* socket options */
2201                 sock_reset_flag(sk, SOCK_LINGER);
2202
2203                 xprt_clear_connected(xprt);
2204
2205                 /* Reset to new socket */
2206                 transport->sock = sock;
2207                 transport->inet = sk;
2208
2209                 write_unlock_bh(&sk->sk_callback_lock);
2210         }
2211
2212         if (!xprt_bound(xprt))
2213                 goto out;
2214
2215         xs_set_memalloc(xprt);
2216
2217         xs_stream_start_connect(transport);
2218
2219         /* Tell the socket layer to start connecting... */
2220         set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state);
2221         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2222         switch (ret) {
2223         case 0:
2224                 xs_set_srcport(transport, sock);
2225                 fallthrough;
2226         case -EINPROGRESS:
2227                 /* SYN_SENT! */
2228                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2229                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2230                 break;
2231         case -EADDRNOTAVAIL:
2232                 /* Source port number is unavailable. Try a new one! */
2233                 transport->srcport = 0;
2234         }
2235 out:
2236         return ret;
2237 }
2238
2239 /**
2240  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2241  * @work: queued work item
2242  *
2243  * Invoked by a work queue tasklet.
2244  */
2245 static void xs_tcp_setup_socket(struct work_struct *work)
2246 {
2247         struct sock_xprt *transport =
2248                 container_of(work, struct sock_xprt, connect_worker.work);
2249         struct socket *sock = transport->sock;
2250         struct rpc_xprt *xprt = &transport->xprt;
2251         int status = -EIO;
2252
2253         if (!sock) {
2254                 sock = xs_create_sock(xprt, transport,
2255                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2256                                 IPPROTO_TCP, true);
2257                 if (IS_ERR(sock)) {
2258                         status = PTR_ERR(sock);
2259                         goto out;
2260                 }
2261         }
2262
2263         dprintk("RPC:       worker connecting xprt %p via %s to "
2264                                 "%s (port %s)\n", xprt,
2265                         xprt->address_strings[RPC_DISPLAY_PROTO],
2266                         xprt->address_strings[RPC_DISPLAY_ADDR],
2267                         xprt->address_strings[RPC_DISPLAY_PORT]);
2268
2269         status = xs_tcp_finish_connecting(xprt, sock);
2270         trace_rpc_socket_connect(xprt, sock, status);
2271         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2272                         xprt, -status, xprt_connected(xprt),
2273                         sock->sk->sk_state);
2274         switch (status) {
2275         default:
2276                 printk("%s: connect returned unhandled error %d\n",
2277                         __func__, status);
2278                 fallthrough;
2279         case -EADDRNOTAVAIL:
2280                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2281                  * and retry
2282                  */
2283                 xs_tcp_force_close(xprt);
2284                 break;
2285         case 0:
2286         case -EINPROGRESS:
2287         case -EALREADY:
2288                 xprt_unlock_connect(xprt, transport);
2289                 return;
2290         case -EINVAL:
2291                 /* Happens, for instance, if the user specified a link
2292                  * local IPv6 address without a scope-id.
2293                  */
2294         case -ECONNREFUSED:
2295         case -ECONNRESET:
2296         case -ENETDOWN:
2297         case -ENETUNREACH:
2298         case -EHOSTUNREACH:
2299         case -EADDRINUSE:
2300         case -ENOBUFS:
2301                 /* xs_tcp_force_close() wakes tasks with a fixed error code.
2302                  * We need to wake them first to ensure the correct error code.
2303                  */
2304                 xprt_wake_pending_tasks(xprt, status);
2305                 xs_tcp_force_close(xprt);
2306                 goto out;
2307         }
2308         status = -EAGAIN;
2309 out:
2310         xprt_clear_connecting(xprt);
2311         xprt_unlock_connect(xprt, transport);
2312         xprt_wake_pending_tasks(xprt, status);
2313 }
2314
2315 /**
2316  * xs_connect - connect a socket to a remote endpoint
2317  * @xprt: pointer to transport structure
2318  * @task: address of RPC task that manages state of connect request
2319  *
2320  * TCP: If the remote end dropped the connection, delay reconnecting.
2321  *
2322  * UDP socket connects are synchronous, but we use a work queue anyway
2323  * to guarantee that even unprivileged user processes can set up a
2324  * socket on a privileged port.
2325  *
2326  * If a UDP socket connect fails, the delay behavior here prevents
2327  * retry floods (hard mounts).
2328  */
2329 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2330 {
2331         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2332         unsigned long delay = 0;
2333
2334         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2335
2336         if (transport->sock != NULL) {
2337                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2338                                 "seconds\n",
2339                                 xprt, xprt->reestablish_timeout / HZ);
2340
2341                 /* Start by resetting any existing state */
2342                 xs_reset_transport(transport);
2343
2344                 delay = xprt_reconnect_delay(xprt);
2345                 xprt_reconnect_backoff(xprt, XS_TCP_INIT_REEST_TO);
2346
2347         } else
2348                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2349
2350         queue_delayed_work(xprtiod_workqueue,
2351                         &transport->connect_worker,
2352                         delay);
2353 }
2354
2355 static void xs_wake_disconnect(struct sock_xprt *transport)
2356 {
2357         if (test_and_clear_bit(XPRT_SOCK_WAKE_DISCONNECT, &transport->sock_state))
2358                 xs_tcp_force_close(&transport->xprt);
2359 }
2360
2361 static void xs_wake_write(struct sock_xprt *transport)
2362 {
2363         if (test_and_clear_bit(XPRT_SOCK_WAKE_WRITE, &transport->sock_state))
2364                 xprt_write_space(&transport->xprt);
2365 }
2366
2367 static void xs_wake_error(struct sock_xprt *transport)
2368 {
2369         int sockerr;
2370
2371         if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2372                 return;
2373         mutex_lock(&transport->recv_mutex);
2374         if (transport->sock == NULL)
2375                 goto out;
2376         if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
2377                 goto out;
2378         sockerr = xchg(&transport->xprt_err, 0);
2379         if (sockerr < 0)
2380                 xprt_wake_pending_tasks(&transport->xprt, sockerr);
2381 out:
2382         mutex_unlock(&transport->recv_mutex);
2383 }
2384
2385 static void xs_wake_pending(struct sock_xprt *transport)
2386 {
2387         if (test_and_clear_bit(XPRT_SOCK_WAKE_PENDING, &transport->sock_state))
2388                 xprt_wake_pending_tasks(&transport->xprt, -EAGAIN);
2389 }
2390
2391 static void xs_error_handle(struct work_struct *work)
2392 {
2393         struct sock_xprt *transport = container_of(work,
2394                         struct sock_xprt, error_worker);
2395
2396         xs_wake_disconnect(transport);
2397         xs_wake_write(transport);
2398         xs_wake_error(transport);
2399         xs_wake_pending(transport);
2400 }
2401
2402 /**
2403  * xs_local_print_stats - display AF_LOCAL socket-specific stats
2404  * @xprt: rpc_xprt struct containing statistics
2405  * @seq: output file
2406  *
2407  */
2408 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2409 {
2410         long idle_time = 0;
2411
2412         if (xprt_connected(xprt))
2413                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2414
2415         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2416                         "%llu %llu %lu %llu %llu\n",
2417                         xprt->stat.bind_count,
2418                         xprt->stat.connect_count,
2419                         xprt->stat.connect_time / HZ,
2420                         idle_time,
2421                         xprt->stat.sends,
2422                         xprt->stat.recvs,
2423                         xprt->stat.bad_xids,
2424                         xprt->stat.req_u,
2425                         xprt->stat.bklog_u,
2426                         xprt->stat.max_slots,
2427                         xprt->stat.sending_u,
2428                         xprt->stat.pending_u);
2429 }
2430
2431 /**
2432  * xs_udp_print_stats - display UDP socket-specific stats
2433  * @xprt: rpc_xprt struct containing statistics
2434  * @seq: output file
2435  *
2436  */
2437 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2438 {
2439         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2440
2441         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2442                         "%lu %llu %llu\n",
2443                         transport->srcport,
2444                         xprt->stat.bind_count,
2445                         xprt->stat.sends,
2446                         xprt->stat.recvs,
2447                         xprt->stat.bad_xids,
2448                         xprt->stat.req_u,
2449                         xprt->stat.bklog_u,
2450                         xprt->stat.max_slots,
2451                         xprt->stat.sending_u,
2452                         xprt->stat.pending_u);
2453 }
2454
2455 /**
2456  * xs_tcp_print_stats - display TCP socket-specific stats
2457  * @xprt: rpc_xprt struct containing statistics
2458  * @seq: output file
2459  *
2460  */
2461 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2462 {
2463         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2464         long idle_time = 0;
2465
2466         if (xprt_connected(xprt))
2467                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2468
2469         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2470                         "%llu %llu %lu %llu %llu\n",
2471                         transport->srcport,
2472                         xprt->stat.bind_count,
2473                         xprt->stat.connect_count,
2474                         xprt->stat.connect_time / HZ,
2475                         idle_time,
2476                         xprt->stat.sends,
2477                         xprt->stat.recvs,
2478                         xprt->stat.bad_xids,
2479                         xprt->stat.req_u,
2480                         xprt->stat.bklog_u,
2481                         xprt->stat.max_slots,
2482                         xprt->stat.sending_u,
2483                         xprt->stat.pending_u);
2484 }
2485
2486 /*
2487  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2488  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2489  * to use the server side send routines.
2490  */
2491 static int bc_malloc(struct rpc_task *task)
2492 {
2493         struct rpc_rqst *rqst = task->tk_rqstp;
2494         size_t size = rqst->rq_callsize;
2495         struct page *page;
2496         struct rpc_buffer *buf;
2497
2498         if (size > PAGE_SIZE - sizeof(struct rpc_buffer)) {
2499                 WARN_ONCE(1, "xprtsock: large bc buffer request (size %zu)\n",
2500                           size);
2501                 return -EINVAL;
2502         }
2503
2504         page = alloc_page(GFP_KERNEL);
2505         if (!page)
2506                 return -ENOMEM;
2507
2508         buf = page_address(page);
2509         buf->len = PAGE_SIZE;
2510
2511         rqst->rq_buffer = buf->data;
2512         rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
2513         return 0;
2514 }
2515
2516 /*
2517  * Free the space allocated in the bc_alloc routine
2518  */
2519 static void bc_free(struct rpc_task *task)
2520 {
2521         void *buffer = task->tk_rqstp->rq_buffer;
2522         struct rpc_buffer *buf;
2523
2524         buf = container_of(buffer, struct rpc_buffer, data);
2525         free_page((unsigned long)buf);
2526 }
2527
2528 static int bc_sendto(struct rpc_rqst *req)
2529 {
2530         struct xdr_buf *xdr = &req->rq_snd_buf;
2531         struct sock_xprt *transport =
2532                         container_of(req->rq_xprt, struct sock_xprt, xprt);
2533         struct msghdr msg = {
2534                 .msg_flags      = 0,
2535         };
2536         rpc_fraghdr marker = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT |
2537                                          (u32)xdr->len);
2538         unsigned int sent = 0;
2539         int err;
2540
2541         req->rq_xtime = ktime_get();
2542         err = xprt_sock_sendmsg(transport->sock, &msg, xdr, 0, marker, &sent);
2543         xdr_free_bvec(xdr);
2544         if (err < 0 || sent != (xdr->len + sizeof(marker)))
2545                 return -EAGAIN;
2546         return sent;
2547 }
2548
2549 /**
2550  * bc_send_request - Send a backchannel Call on a TCP socket
2551  * @req: rpc_rqst containing Call message to be sent
2552  *
2553  * xpt_mutex ensures @rqstp's whole message is written to the socket
2554  * without interruption.
2555  *
2556  * Return values:
2557  *   %0 if the message was sent successfully
2558  *   %ENOTCONN if the message was not sent
2559  */
2560 static int bc_send_request(struct rpc_rqst *req)
2561 {
2562         struct svc_xprt *xprt;
2563         int len;
2564
2565         /*
2566          * Get the server socket associated with this callback xprt
2567          */
2568         xprt = req->rq_xprt->bc_xprt;
2569
2570         /*
2571          * Grab the mutex to serialize data as the connection is shared
2572          * with the fore channel
2573          */
2574         mutex_lock(&xprt->xpt_mutex);
2575         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2576                 len = -ENOTCONN;
2577         else
2578                 len = bc_sendto(req);
2579         mutex_unlock(&xprt->xpt_mutex);
2580
2581         if (len > 0)
2582                 len = 0;
2583
2584         return len;
2585 }
2586
2587 /*
2588  * The close routine. Since this is client initiated, we do nothing
2589  */
2590
2591 static void bc_close(struct rpc_xprt *xprt)
2592 {
2593         xprt_disconnect_done(xprt);
2594 }
2595
2596 /*
2597  * The xprt destroy routine. Again, because this connection is client
2598  * initiated, we do nothing
2599  */
2600
2601 static void bc_destroy(struct rpc_xprt *xprt)
2602 {
2603         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2604
2605         xs_xprt_free(xprt);
2606         module_put(THIS_MODULE);
2607 }
2608
2609 static const struct rpc_xprt_ops xs_local_ops = {
2610         .reserve_xprt           = xprt_reserve_xprt,
2611         .release_xprt           = xprt_release_xprt,
2612         .alloc_slot             = xprt_alloc_slot,
2613         .free_slot              = xprt_free_slot,
2614         .rpcbind                = xs_local_rpcbind,
2615         .set_port               = xs_local_set_port,
2616         .connect                = xs_local_connect,
2617         .buf_alloc              = rpc_malloc,
2618         .buf_free               = rpc_free,
2619         .prepare_request        = xs_stream_prepare_request,
2620         .send_request           = xs_local_send_request,
2621         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2622         .close                  = xs_close,
2623         .destroy                = xs_destroy,
2624         .print_stats            = xs_local_print_stats,
2625         .enable_swap            = xs_enable_swap,
2626         .disable_swap           = xs_disable_swap,
2627 };
2628
2629 static const struct rpc_xprt_ops xs_udp_ops = {
2630         .set_buffer_size        = xs_udp_set_buffer_size,
2631         .reserve_xprt           = xprt_reserve_xprt_cong,
2632         .release_xprt           = xprt_release_xprt_cong,
2633         .alloc_slot             = xprt_alloc_slot,
2634         .free_slot              = xprt_free_slot,
2635         .rpcbind                = rpcb_getport_async,
2636         .set_port               = xs_set_port,
2637         .connect                = xs_connect,
2638         .buf_alloc              = rpc_malloc,
2639         .buf_free               = rpc_free,
2640         .send_request           = xs_udp_send_request,
2641         .wait_for_reply_request = xprt_wait_for_reply_request_rtt,
2642         .timer                  = xs_udp_timer,
2643         .release_request        = xprt_release_rqst_cong,
2644         .close                  = xs_close,
2645         .destroy                = xs_destroy,
2646         .print_stats            = xs_udp_print_stats,
2647         .enable_swap            = xs_enable_swap,
2648         .disable_swap           = xs_disable_swap,
2649         .inject_disconnect      = xs_inject_disconnect,
2650 };
2651
2652 static const struct rpc_xprt_ops xs_tcp_ops = {
2653         .reserve_xprt           = xprt_reserve_xprt,
2654         .release_xprt           = xprt_release_xprt,
2655         .alloc_slot             = xprt_alloc_slot,
2656         .free_slot              = xprt_free_slot,
2657         .rpcbind                = rpcb_getport_async,
2658         .set_port               = xs_set_port,
2659         .connect                = xs_connect,
2660         .buf_alloc              = rpc_malloc,
2661         .buf_free               = rpc_free,
2662         .prepare_request        = xs_stream_prepare_request,
2663         .send_request           = xs_tcp_send_request,
2664         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2665         .close                  = xs_tcp_shutdown,
2666         .destroy                = xs_destroy,
2667         .set_connect_timeout    = xs_tcp_set_connect_timeout,
2668         .print_stats            = xs_tcp_print_stats,
2669         .enable_swap            = xs_enable_swap,
2670         .disable_swap           = xs_disable_swap,
2671         .inject_disconnect      = xs_inject_disconnect,
2672 #ifdef CONFIG_SUNRPC_BACKCHANNEL
2673         .bc_setup               = xprt_setup_bc,
2674         .bc_maxpayload          = xs_tcp_bc_maxpayload,
2675         .bc_num_slots           = xprt_bc_max_slots,
2676         .bc_free_rqst           = xprt_free_bc_rqst,
2677         .bc_destroy             = xprt_destroy_bc,
2678 #endif
2679 };
2680
2681 /*
2682  * The rpc_xprt_ops for the server backchannel
2683  */
2684
2685 static const struct rpc_xprt_ops bc_tcp_ops = {
2686         .reserve_xprt           = xprt_reserve_xprt,
2687         .release_xprt           = xprt_release_xprt,
2688         .alloc_slot             = xprt_alloc_slot,
2689         .free_slot              = xprt_free_slot,
2690         .buf_alloc              = bc_malloc,
2691         .buf_free               = bc_free,
2692         .send_request           = bc_send_request,
2693         .wait_for_reply_request = xprt_wait_for_reply_request_def,
2694         .close                  = bc_close,
2695         .destroy                = bc_destroy,
2696         .print_stats            = xs_tcp_print_stats,
2697         .enable_swap            = xs_enable_swap,
2698         .disable_swap           = xs_disable_swap,
2699         .inject_disconnect      = xs_inject_disconnect,
2700 };
2701
2702 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2703 {
2704         static const struct sockaddr_in sin = {
2705                 .sin_family             = AF_INET,
2706                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2707         };
2708         static const struct sockaddr_in6 sin6 = {
2709                 .sin6_family            = AF_INET6,
2710                 .sin6_addr              = IN6ADDR_ANY_INIT,
2711         };
2712
2713         switch (family) {
2714         case AF_LOCAL:
2715                 break;
2716         case AF_INET:
2717                 memcpy(sap, &sin, sizeof(sin));
2718                 break;
2719         case AF_INET6:
2720                 memcpy(sap, &sin6, sizeof(sin6));
2721                 break;
2722         default:
2723                 dprintk("RPC:       %s: Bad address family\n", __func__);
2724                 return -EAFNOSUPPORT;
2725         }
2726         return 0;
2727 }
2728
2729 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2730                                       unsigned int slot_table_size,
2731                                       unsigned int max_slot_table_size)
2732 {
2733         struct rpc_xprt *xprt;
2734         struct sock_xprt *new;
2735
2736         if (args->addrlen > sizeof(xprt->addr)) {
2737                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2738                 return ERR_PTR(-EBADF);
2739         }
2740
2741         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2742                         max_slot_table_size);
2743         if (xprt == NULL) {
2744                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2745                                 "rpc_xprt\n");
2746                 return ERR_PTR(-ENOMEM);
2747         }
2748
2749         new = container_of(xprt, struct sock_xprt, xprt);
2750         mutex_init(&new->recv_mutex);
2751         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2752         xprt->addrlen = args->addrlen;
2753         if (args->srcaddr)
2754                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2755         else {
2756                 int err;
2757                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2758                                         (struct sockaddr *)&new->srcaddr);
2759                 if (err != 0) {
2760                         xprt_free(xprt);
2761                         return ERR_PTR(err);
2762                 }
2763         }
2764
2765         return xprt;
2766 }
2767
2768 static const struct rpc_timeout xs_local_default_timeout = {
2769         .to_initval = 10 * HZ,
2770         .to_maxval = 10 * HZ,
2771         .to_retries = 2,
2772 };
2773
2774 /**
2775  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2776  * @args: rpc transport creation arguments
2777  *
2778  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2779  */
2780 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2781 {
2782         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2783         struct sock_xprt *transport;
2784         struct rpc_xprt *xprt;
2785         struct rpc_xprt *ret;
2786
2787         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2788                         xprt_max_tcp_slot_table_entries);
2789         if (IS_ERR(xprt))
2790                 return xprt;
2791         transport = container_of(xprt, struct sock_xprt, xprt);
2792
2793         xprt->prot = 0;
2794         xprt->xprt_class = &xs_local_transport;
2795         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2796
2797         xprt->bind_timeout = XS_BIND_TO;
2798         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2799         xprt->idle_timeout = XS_IDLE_DISC_TO;
2800
2801         xprt->ops = &xs_local_ops;
2802         xprt->timeout = &xs_local_default_timeout;
2803
2804         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2805         INIT_WORK(&transport->error_worker, xs_error_handle);
2806         INIT_DELAYED_WORK(&transport->connect_worker, xs_dummy_setup_socket);
2807
2808         switch (sun->sun_family) {
2809         case AF_LOCAL:
2810                 if (sun->sun_path[0] != '/') {
2811                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2812                                         sun->sun_path);
2813                         ret = ERR_PTR(-EINVAL);
2814                         goto out_err;
2815                 }
2816                 xprt_set_bound(xprt);
2817                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2818                 ret = ERR_PTR(xs_local_setup_socket(transport));
2819                 if (ret)
2820                         goto out_err;
2821                 break;
2822         default:
2823                 ret = ERR_PTR(-EAFNOSUPPORT);
2824                 goto out_err;
2825         }
2826
2827         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2828                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2829
2830         if (try_module_get(THIS_MODULE))
2831                 return xprt;
2832         ret = ERR_PTR(-EINVAL);
2833 out_err:
2834         xs_xprt_free(xprt);
2835         return ret;
2836 }
2837
2838 static const struct rpc_timeout xs_udp_default_timeout = {
2839         .to_initval = 5 * HZ,
2840         .to_maxval = 30 * HZ,
2841         .to_increment = 5 * HZ,
2842         .to_retries = 5,
2843 };
2844
2845 /**
2846  * xs_setup_udp - Set up transport to use a UDP socket
2847  * @args: rpc transport creation arguments
2848  *
2849  */
2850 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2851 {
2852         struct sockaddr *addr = args->dstaddr;
2853         struct rpc_xprt *xprt;
2854         struct sock_xprt *transport;
2855         struct rpc_xprt *ret;
2856
2857         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2858                         xprt_udp_slot_table_entries);
2859         if (IS_ERR(xprt))
2860                 return xprt;
2861         transport = container_of(xprt, struct sock_xprt, xprt);
2862
2863         xprt->prot = IPPROTO_UDP;
2864         xprt->xprt_class = &xs_udp_transport;
2865         /* XXX: header size can vary due to auth type, IPv6, etc. */
2866         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2867
2868         xprt->bind_timeout = XS_BIND_TO;
2869         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2870         xprt->idle_timeout = XS_IDLE_DISC_TO;
2871
2872         xprt->ops = &xs_udp_ops;
2873
2874         xprt->timeout = &xs_udp_default_timeout;
2875
2876         INIT_WORK(&transport->recv_worker, xs_udp_data_receive_workfn);
2877         INIT_WORK(&transport->error_worker, xs_error_handle);
2878         INIT_DELAYED_WORK(&transport->connect_worker, xs_udp_setup_socket);
2879
2880         switch (addr->sa_family) {
2881         case AF_INET:
2882                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2883                         xprt_set_bound(xprt);
2884
2885                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2886                 break;
2887         case AF_INET6:
2888                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2889                         xprt_set_bound(xprt);
2890
2891                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2892                 break;
2893         default:
2894                 ret = ERR_PTR(-EAFNOSUPPORT);
2895                 goto out_err;
2896         }
2897
2898         if (xprt_bound(xprt))
2899                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2900                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2901                                 xprt->address_strings[RPC_DISPLAY_PORT],
2902                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2903         else
2904                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2905                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2906                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2907
2908         if (try_module_get(THIS_MODULE))
2909                 return xprt;
2910         ret = ERR_PTR(-EINVAL);
2911 out_err:
2912         xs_xprt_free(xprt);
2913         return ret;
2914 }
2915
2916 static const struct rpc_timeout xs_tcp_default_timeout = {
2917         .to_initval = 60 * HZ,
2918         .to_maxval = 60 * HZ,
2919         .to_retries = 2,
2920 };
2921
2922 /**
2923  * xs_setup_tcp - Set up transport to use a TCP socket
2924  * @args: rpc transport creation arguments
2925  *
2926  */
2927 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2928 {
2929         struct sockaddr *addr = args->dstaddr;
2930         struct rpc_xprt *xprt;
2931         struct sock_xprt *transport;
2932         struct rpc_xprt *ret;
2933         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2934
2935         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2936                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2937
2938         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2939                         max_slot_table_size);
2940         if (IS_ERR(xprt))
2941                 return xprt;
2942         transport = container_of(xprt, struct sock_xprt, xprt);
2943
2944         xprt->prot = IPPROTO_TCP;
2945         xprt->xprt_class = &xs_tcp_transport;
2946         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2947
2948         xprt->bind_timeout = XS_BIND_TO;
2949         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2950         xprt->idle_timeout = XS_IDLE_DISC_TO;
2951
2952         xprt->ops = &xs_tcp_ops;
2953         xprt->timeout = &xs_tcp_default_timeout;
2954
2955         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
2956         xprt->connect_timeout = xprt->timeout->to_initval *
2957                 (xprt->timeout->to_retries + 1);
2958
2959         INIT_WORK(&transport->recv_worker, xs_stream_data_receive_workfn);
2960         INIT_WORK(&transport->error_worker, xs_error_handle);
2961         INIT_DELAYED_WORK(&transport->connect_worker, xs_tcp_setup_socket);
2962
2963         switch (addr->sa_family) {
2964         case AF_INET:
2965                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2966                         xprt_set_bound(xprt);
2967
2968                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2969                 break;
2970         case AF_INET6:
2971                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2972                         xprt_set_bound(xprt);
2973
2974                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2975                 break;
2976         default:
2977                 ret = ERR_PTR(-EAFNOSUPPORT);
2978                 goto out_err;
2979         }
2980
2981         if (xprt_bound(xprt))
2982                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2983                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2984                                 xprt->address_strings[RPC_DISPLAY_PORT],
2985                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2986         else
2987                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2988                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2989                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2990
2991         if (try_module_get(THIS_MODULE))
2992                 return xprt;
2993         ret = ERR_PTR(-EINVAL);
2994 out_err:
2995         xs_xprt_free(xprt);
2996         return ret;
2997 }
2998
2999 /**
3000  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
3001  * @args: rpc transport creation arguments
3002  *
3003  */
3004 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
3005 {
3006         struct sockaddr *addr = args->dstaddr;
3007         struct rpc_xprt *xprt;
3008         struct sock_xprt *transport;
3009         struct svc_sock *bc_sock;
3010         struct rpc_xprt *ret;
3011
3012         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
3013                         xprt_tcp_slot_table_entries);
3014         if (IS_ERR(xprt))
3015                 return xprt;
3016         transport = container_of(xprt, struct sock_xprt, xprt);
3017
3018         xprt->prot = IPPROTO_TCP;
3019         xprt->xprt_class = &xs_bc_tcp_transport;
3020         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
3021         xprt->timeout = &xs_tcp_default_timeout;
3022
3023         /* backchannel */
3024         xprt_set_bound(xprt);
3025         xprt->bind_timeout = 0;
3026         xprt->reestablish_timeout = 0;
3027         xprt->idle_timeout = 0;
3028
3029         xprt->ops = &bc_tcp_ops;
3030
3031         switch (addr->sa_family) {
3032         case AF_INET:
3033                 xs_format_peer_addresses(xprt, "tcp",
3034                                          RPCBIND_NETID_TCP);
3035                 break;
3036         case AF_INET6:
3037                 xs_format_peer_addresses(xprt, "tcp",
3038                                    RPCBIND_NETID_TCP6);
3039                 break;
3040         default:
3041                 ret = ERR_PTR(-EAFNOSUPPORT);
3042                 goto out_err;
3043         }
3044
3045         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
3046                         xprt->address_strings[RPC_DISPLAY_ADDR],
3047                         xprt->address_strings[RPC_DISPLAY_PORT],
3048                         xprt->address_strings[RPC_DISPLAY_PROTO]);
3049
3050         /*
3051          * Once we've associated a backchannel xprt with a connection,
3052          * we want to keep it around as long as the connection lasts,
3053          * in case we need to start using it for a backchannel again;
3054          * this reference won't be dropped until bc_xprt is destroyed.
3055          */
3056         xprt_get(xprt);
3057         args->bc_xprt->xpt_bc_xprt = xprt;
3058         xprt->bc_xprt = args->bc_xprt;
3059         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
3060         transport->sock = bc_sock->sk_sock;
3061         transport->inet = bc_sock->sk_sk;
3062
3063         /*
3064          * Since we don't want connections for the backchannel, we set
3065          * the xprt status to connected
3066          */
3067         xprt_set_connected(xprt);
3068
3069         if (try_module_get(THIS_MODULE))
3070                 return xprt;
3071
3072         args->bc_xprt->xpt_bc_xprt = NULL;
3073         args->bc_xprt->xpt_bc_xps = NULL;
3074         xprt_put(xprt);
3075         ret = ERR_PTR(-EINVAL);
3076 out_err:
3077         xs_xprt_free(xprt);
3078         return ret;
3079 }
3080
3081 static struct xprt_class        xs_local_transport = {
3082         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3083         .name           = "named UNIX socket",
3084         .owner          = THIS_MODULE,
3085         .ident          = XPRT_TRANSPORT_LOCAL,
3086         .setup          = xs_setup_local,
3087         .netid          = { "" },
3088 };
3089
3090 static struct xprt_class        xs_udp_transport = {
3091         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3092         .name           = "udp",
3093         .owner          = THIS_MODULE,
3094         .ident          = XPRT_TRANSPORT_UDP,
3095         .setup          = xs_setup_udp,
3096         .netid          = { "udp", "udp6", "" },
3097 };
3098
3099 static struct xprt_class        xs_tcp_transport = {
3100         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3101         .name           = "tcp",
3102         .owner          = THIS_MODULE,
3103         .ident          = XPRT_TRANSPORT_TCP,
3104         .setup          = xs_setup_tcp,
3105         .netid          = { "tcp", "tcp6", "" },
3106 };
3107
3108 static struct xprt_class        xs_bc_tcp_transport = {
3109         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3110         .name           = "tcp NFSv4.1 backchannel",
3111         .owner          = THIS_MODULE,
3112         .ident          = XPRT_TRANSPORT_BC_TCP,
3113         .setup          = xs_setup_bc_tcp,
3114         .netid          = { "" },
3115 };
3116
3117 /**
3118  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3119  *
3120  */
3121 int init_socket_xprt(void)
3122 {
3123         if (!sunrpc_table_header)
3124                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3125
3126         xprt_register_transport(&xs_local_transport);
3127         xprt_register_transport(&xs_udp_transport);
3128         xprt_register_transport(&xs_tcp_transport);
3129         xprt_register_transport(&xs_bc_tcp_transport);
3130
3131         return 0;
3132 }
3133
3134 /**
3135  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3136  *
3137  */
3138 void cleanup_socket_xprt(void)
3139 {
3140         if (sunrpc_table_header) {
3141                 unregister_sysctl_table(sunrpc_table_header);
3142                 sunrpc_table_header = NULL;
3143         }
3144
3145         xprt_unregister_transport(&xs_local_transport);
3146         xprt_unregister_transport(&xs_udp_transport);
3147         xprt_unregister_transport(&xs_tcp_transport);
3148         xprt_unregister_transport(&xs_bc_tcp_transport);
3149 }
3150
3151 static int param_set_uint_minmax(const char *val,
3152                 const struct kernel_param *kp,
3153                 unsigned int min, unsigned int max)
3154 {
3155         unsigned int num;
3156         int ret;
3157
3158         if (!val)
3159                 return -EINVAL;
3160         ret = kstrtouint(val, 0, &num);
3161         if (ret)
3162                 return ret;
3163         if (num < min || num > max)
3164                 return -EINVAL;
3165         *((unsigned int *)kp->arg) = num;
3166         return 0;
3167 }
3168
3169 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3170 {
3171         return param_set_uint_minmax(val, kp,
3172                         RPC_MIN_RESVPORT,
3173                         RPC_MAX_RESVPORT);
3174 }
3175
3176 static const struct kernel_param_ops param_ops_portnr = {
3177         .set = param_set_portnr,
3178         .get = param_get_uint,
3179 };
3180
3181 #define param_check_portnr(name, p) \
3182         __param_check(name, p, unsigned int);
3183
3184 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3185 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3186
3187 static int param_set_slot_table_size(const char *val,
3188                                      const struct kernel_param *kp)
3189 {
3190         return param_set_uint_minmax(val, kp,
3191                         RPC_MIN_SLOT_TABLE,
3192                         RPC_MAX_SLOT_TABLE);
3193 }
3194
3195 static const struct kernel_param_ops param_ops_slot_table_size = {
3196         .set = param_set_slot_table_size,
3197         .get = param_get_uint,
3198 };
3199
3200 #define param_check_slot_table_size(name, p) \
3201         __param_check(name, p, unsigned int);
3202
3203 static int param_set_max_slot_table_size(const char *val,
3204                                      const struct kernel_param *kp)
3205 {
3206         return param_set_uint_minmax(val, kp,
3207                         RPC_MIN_SLOT_TABLE,
3208                         RPC_MAX_SLOT_TABLE_LIMIT);
3209 }
3210
3211 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3212         .set = param_set_max_slot_table_size,
3213         .get = param_get_uint,
3214 };
3215
3216 #define param_check_max_slot_table_size(name, p) \
3217         __param_check(name, p, unsigned int);
3218
3219 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3220                    slot_table_size, 0644);
3221 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3222                    max_slot_table_size, 0644);
3223 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3224                    slot_table_size, 0644);