net/sunrpc/xprtsock.c

   1 /*
   2  * linux/net/sunrpc/xprtsock.c
   3  *
   4  * Client-side transport implementation for sockets.
   5  *
   6  * TCP callback races fixes (C) 1998 Red Hat
   7  * TCP send fixes (C) 1998 Red Hat
   8  * TCP NFS related read + write fixes
   9  *  (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
  10  *
  11  * Rewrite of larges part of the code in order to stabilize TCP stuff.
  12  * Fix behaviour when socket buffer is full.
  13  *  (C) 1999 Trond Myklebust <trond.myklebust@fys.uio.no>
  14  *
  15  * IP socket transport implementation, (C) 2005 Chuck Lever <cel@netapp.com>
  16  *
  17  * IPv6 support contributed by Gilles Quillard, Bull Open Source, 2005.
  18  *   <gilles.quillard@bull.net>
  19  */
  20
  21 #include <linux/types.h>
  22 #include <linux/string.h>
  23 #include <linux/slab.h>
  24 #include <linux/module.h>
  25 #include <linux/capability.h>
  26 #include <linux/pagemap.h>
  27 #include <linux/errno.h>
  28 #include <linux/socket.h>
  29 #include <linux/in.h>
  30 #include <linux/net.h>
  31 #include <linux/mm.h>
  32 #include <linux/un.h>
  33 #include <linux/udp.h>
  34 #include <linux/tcp.h>
  35 #include <linux/sunrpc/clnt.h>
  36 #include <linux/sunrpc/addr.h>
  37 #include <linux/sunrpc/sched.h>
  38 #include <linux/sunrpc/svcsock.h>
  39 #include <linux/sunrpc/xprtsock.h>
  40 #include <linux/file.h>
  41 #ifdef CONFIG_SUNRPC_BACKCHANNEL
  42 #include <linux/sunrpc/bc_xprt.h>
  43 #endif
  44
  45 #include <net/sock.h>
  46 #include <net/checksum.h>
  47 #include <net/udp.h>
  48 #include <net/tcp.h>
  49
  50 #include <trace/events/sunrpc.h>
  51
  52 #include "sunrpc.h"
  53
  54 static void xs_close(struct rpc_xprt *xprt);
  55
  56 /*
  57  * xprtsock tunables
  58  */
  59 static unsigned int xprt_udp_slot_table_entries = RPC_DEF_SLOT_TABLE;
  60 static unsigned int xprt_tcp_slot_table_entries = RPC_MIN_SLOT_TABLE;
  61 static unsigned int xprt_max_tcp_slot_table_entries = RPC_MAX_SLOT_TABLE;
  62
  63 static unsigned int xprt_min_resvport = RPC_DEF_MIN_RESVPORT;
  64 static unsigned int xprt_max_resvport = RPC_DEF_MAX_RESVPORT;
  65
  66 #define XS_TCP_LINGER_TO        (15U * HZ)
  67 static unsigned int xs_tcp_fin_timeout __read_mostly = XS_TCP_LINGER_TO;
  68
  69 /*
  70  * We can register our own files under /proc/sys/sunrpc by
  71  * calling register_sysctl_table() again.  The files in that
  72  * directory become the union of all files registered there.
  73  *
  74  * We simply need to make sure that we don't collide with
  75  * someone else's file names!
  76  */
  77
  78 #ifdef RPC_DEBUG
  79
  80 static unsigned int min_slot_table_size = RPC_MIN_SLOT_TABLE;
  81 static unsigned int max_slot_table_size = RPC_MAX_SLOT_TABLE;
  82 static unsigned int max_tcp_slot_table_limit = RPC_MAX_SLOT_TABLE_LIMIT;
  83 static unsigned int xprt_min_resvport_limit = RPC_MIN_RESVPORT;
  84 static unsigned int xprt_max_resvport_limit = RPC_MAX_RESVPORT;
  85
  86 static struct ctl_table_header *sunrpc_table_header;
  87
  88 /*
  89  * FIXME: changing the UDP slot table size should also resize the UDP
  90  *        socket buffers for existing UDP transports
  91  */
  92 static struct ctl_table xs_tunables_table[] = {
  93         {
  94                 .procname       = "udp_slot_table_entries",
  95                 .data           = &xprt_udp_slot_table_entries,
  96                 .maxlen         = sizeof(unsigned int),
  97                 .mode           = 0644,
  98                 .proc_handler   = proc_dointvec_minmax,
  99                 .extra1         = &min_slot_table_size,
 100                 .extra2         = &max_slot_table_size
 101         },
 102         {
 103                 .procname       = "tcp_slot_table_entries",
 104                 .data           = &xprt_tcp_slot_table_entries,
 105                 .maxlen         = sizeof(unsigned int),
 106                 .mode           = 0644,
 107                 .proc_handler   = proc_dointvec_minmax,
 108                 .extra1         = &min_slot_table_size,
 109                 .extra2         = &max_slot_table_size
 110         },
 111         {
 112                 .procname       = "tcp_max_slot_table_entries",
 113                 .data           = &xprt_max_tcp_slot_table_entries,
 114                 .maxlen         = sizeof(unsigned int),
 115                 .mode           = 0644,
 116                 .proc_handler   = proc_dointvec_minmax,
 117                 .extra1         = &min_slot_table_size,
 118                 .extra2         = &max_tcp_slot_table_limit
 119         },
 120         {
 121                 .procname       = "min_resvport",
 122                 .data           = &xprt_min_resvport,
 123                 .maxlen         = sizeof(unsigned int),
 124                 .mode           = 0644,
 125                 .proc_handler   = proc_dointvec_minmax,
 126                 .extra1         = &xprt_min_resvport_limit,
 127                 .extra2         = &xprt_max_resvport_limit
 128         },
 129         {
 130                 .procname       = "max_resvport",
 131                 .data           = &xprt_max_resvport,
 132                 .maxlen         = sizeof(unsigned int),
 133                 .mode           = 0644,
 134                 .proc_handler   = proc_dointvec_minmax,
 135                 .extra1         = &xprt_min_resvport_limit,
 136                 .extra2         = &xprt_max_resvport_limit
 137         },
 138         {
 139                 .procname       = "tcp_fin_timeout",
 140                 .data           = &xs_tcp_fin_timeout,
 141                 .maxlen         = sizeof(xs_tcp_fin_timeout),
 142                 .mode           = 0644,
 143                 .proc_handler   = proc_dointvec_jiffies,
 144         },
 145         { },
 146 };
 147
 148 static struct ctl_table sunrpc_table[] = {
 149         {
 150                 .procname       = "sunrpc",
 151                 .mode           = 0555,
 152                 .child          = xs_tunables_table
 153         },
 154         { },
 155 };
 156
 157 #endif
 158
 159 /*
 160  * Wait duration for a reply from the RPC portmapper.
 161  */
 162 #define XS_BIND_TO              (60U * HZ)
 163
 164 /*
 165  * Delay if a UDP socket connect error occurs.  This is most likely some
 166  * kind of resource problem on the local host.
 167  */
 168 #define XS_UDP_REEST_TO         (2U * HZ)
 169
 170 /*
 171  * The reestablish timeout allows clients to delay for a bit before attempting
 172  * to reconnect to a server that just dropped our connection.
 173  *
 174  * We implement an exponential backoff when trying to reestablish a TCP
 175  * transport connection with the server.  Some servers like to drop a TCP
 176  * connection when they are overworked, so we start with a short timeout and
 177  * increase over time if the server is down or not responding.
 178  */
 179 #define XS_TCP_INIT_REEST_TO    (3U * HZ)
 180 #define XS_TCP_MAX_REEST_TO     (5U * 60 * HZ)
 181
 182 /*
 183  * TCP idle timeout; client drops the transport socket if it is idle
 184  * for this long.  Note that we also timeout UDP sockets to prevent
 185  * holding port numbers when there is no RPC traffic.
 186  */
 187 #define XS_IDLE_DISC_TO         (5U * 60 * HZ)
 188
 189 #ifdef RPC_DEBUG
 190 # undef  RPC_DEBUG_DATA
 191 # define RPCDBG_FACILITY        RPCDBG_TRANS
 192 #endif
 193
 194 #ifdef RPC_DEBUG_DATA
 195 static void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 196 {
 197         u8 *buf = (u8 *) packet;
 198         int j;
 199
 200         dprintk("RPC:       %s\n", msg);
 201         for (j = 0; j < count && j < 128; j += 4) {
 202                 if (!(j & 31)) {
 203                         if (j)
 204                                 dprintk("\n");
 205                         dprintk("0x%04x ", j);
 206                 }
 207                 dprintk("%02x%02x%02x%02x ",
 208                         buf[j], buf[j+1], buf[j+2], buf[j+3]);
 209         }
 210         dprintk("\n");
 211 }
 212 #else
 213 static inline void xs_pktdump(char *msg, u32 *packet, unsigned int count)
 214 {
 215         /* NOP */
 216 }
 217 #endif
 218
 219 struct sock_xprt {
 220         struct rpc_xprt         xprt;
 221
 222         /*
 223          * Network layer
 224          */
 225         struct socket *         sock;
 226         struct sock *           inet;
 227
 228         /*
 229          * State of TCP reply receive
 230          */
 231         __be32                  tcp_fraghdr,
 232                                 tcp_xid,
 233                                 tcp_calldir;
 234
 235         u32                     tcp_offset,
 236                                 tcp_reclen;
 237
 238         unsigned long           tcp_copied,
 239                                 tcp_flags;
 240
 241         /*
 242          * Connection of transports
 243          */
 244         struct delayed_work     connect_worker;
 245         struct sockaddr_storage srcaddr;
 246         unsigned short          srcport;
 247
 248         /*
 249          * UDP socket buffer size parameters
 250          */
 251         size_t                  rcvsize,
 252                                 sndsize;
 253
 254         /*
 255          * Saved socket callback addresses
 256          */
 257         void                    (*old_data_ready)(struct sock *);
 258         void                    (*old_state_change)(struct sock *);
 259         void                    (*old_write_space)(struct sock *);
 260         void                    (*old_error_report)(struct sock *);
 261 };
 262
 263 /*
 264  * TCP receive state flags
 265  */
 266 #define TCP_RCV_LAST_FRAG       (1UL << 0)
 267 #define TCP_RCV_COPY_FRAGHDR    (1UL << 1)
 268 #define TCP_RCV_COPY_XID        (1UL << 2)
 269 #define TCP_RCV_COPY_DATA       (1UL << 3)
 270 #define TCP_RCV_READ_CALLDIR    (1UL << 4)
 271 #define TCP_RCV_COPY_CALLDIR    (1UL << 5)
 272
 273 /*
 274  * TCP RPC flags
 275  */
 276 #define TCP_RPC_REPLY           (1UL << 6)
 277
 278 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
 279 {
 280         return (struct rpc_xprt *) sk->sk_user_data;
 281 }
 282
 283 static inline struct sockaddr *xs_addr(struct rpc_xprt *xprt)
 284 {
 285         return (struct sockaddr *) &xprt->addr;
 286 }
 287
 288 static inline struct sockaddr_un *xs_addr_un(struct rpc_xprt *xprt)
 289 {
 290         return (struct sockaddr_un *) &xprt->addr;
 291 }
 292
 293 static inline struct sockaddr_in *xs_addr_in(struct rpc_xprt *xprt)
 294 {
 295         return (struct sockaddr_in *) &xprt->addr;
 296 }
 297
 298 static inline struct sockaddr_in6 *xs_addr_in6(struct rpc_xprt *xprt)
 299 {
 300         return (struct sockaddr_in6 *) &xprt->addr;
 301 }
 302
 303 static void xs_format_common_peer_addresses(struct rpc_xprt *xprt)
 304 {
 305         struct sockaddr *sap = xs_addr(xprt);
 306         struct sockaddr_in6 *sin6;
 307         struct sockaddr_in *sin;
 308         struct sockaddr_un *sun;
 309         char buf[128];
 310
 311         switch (sap->sa_family) {
 312         case AF_LOCAL:
 313                 sun = xs_addr_un(xprt);
 314                 strlcpy(buf, sun->sun_path, sizeof(buf));
 315                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 316                                                 kstrdup(buf, GFP_KERNEL);
 317                 break;
 318         case AF_INET:
 319                 (void)rpc_ntop(sap, buf, sizeof(buf));
 320                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 321                                                 kstrdup(buf, GFP_KERNEL);
 322                 sin = xs_addr_in(xprt);
 323                 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 324                 break;
 325         case AF_INET6:
 326                 (void)rpc_ntop(sap, buf, sizeof(buf));
 327                 xprt->address_strings[RPC_DISPLAY_ADDR] =
 328                                                 kstrdup(buf, GFP_KERNEL);
 329                 sin6 = xs_addr_in6(xprt);
 330                 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 331                 break;
 332         default:
 333                 BUG();
 334         }
 335
 336         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 337 }
 338
 339 static void xs_format_common_peer_ports(struct rpc_xprt *xprt)
 340 {
 341         struct sockaddr *sap = xs_addr(xprt);
 342         char buf[128];
 343
 344         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 345         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 346
 347         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 348         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 349 }
 350
 351 static void xs_format_peer_addresses(struct rpc_xprt *xprt,
 352                                      const char *protocol,
 353                                      const char *netid)
 354 {
 355         xprt->address_strings[RPC_DISPLAY_PROTO] = protocol;
 356         xprt->address_strings[RPC_DISPLAY_NETID] = netid;
 357         xs_format_common_peer_addresses(xprt);
 358         xs_format_common_peer_ports(xprt);
 359 }
 360
 361 static void xs_update_peer_port(struct rpc_xprt *xprt)
 362 {
 363         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 364         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 365
 366         xs_format_common_peer_ports(xprt);
 367 }
 368
 369 static void xs_free_peer_addresses(struct rpc_xprt *xprt)
 370 {
 371         unsigned int i;
 372
 373         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 374                 switch (i) {
 375                 case RPC_DISPLAY_PROTO:
 376                 case RPC_DISPLAY_NETID:
 377                         continue;
 378                 default:
 379                         kfree(xprt->address_strings[i]);
 380                 }
 381 }
 382
 383 #define XS_SENDMSG_FLAGS        (MSG_DONTWAIT | MSG_NOSIGNAL)
 384
 385 static int xs_send_kvec(struct socket *sock, struct sockaddr *addr, int addrlen, struct kvec *vec, unsigned int base, int more)
 386 {
 387         struct msghdr msg = {
 388                 .msg_name       = addr,
 389                 .msg_namelen    = addrlen,
 390                 .msg_flags      = XS_SENDMSG_FLAGS | (more ? MSG_MORE : 0),
 391         };
 392         struct kvec iov = {
 393                 .iov_base       = vec->iov_base + base,
 394                 .iov_len        = vec->iov_len - base,
 395         };
 396
 397         if (iov.iov_len != 0)
 398                 return kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len);
 399         return kernel_sendmsg(sock, &msg, NULL, 0, 0);
 400 }
 401
 402 static int xs_send_pagedata(struct socket *sock, struct xdr_buf *xdr, unsigned int base, int more, bool zerocopy)
 403 {
 404         ssize_t (*do_sendpage)(struct socket *sock, struct page *page,
 405                         int offset, size_t size, int flags);
 406         struct page **ppage;
 407         unsigned int remainder;
 408         int err, sent = 0;
 409
 410         remainder = xdr->page_len - base;
 411         base += xdr->page_base;
 412         ppage = xdr->pages + (base >> PAGE_SHIFT);
 413         base &= ~PAGE_MASK;
 414         do_sendpage = sock->ops->sendpage;
 415         if (!zerocopy)
 416                 do_sendpage = sock_no_sendpage;
 417         for(;;) {
 418                 unsigned int len = min_t(unsigned int, PAGE_SIZE - base, remainder);
 419                 int flags = XS_SENDMSG_FLAGS;
 420
 421                 remainder -= len;
 422                 if (remainder != 0 || more)
 423                         flags |= MSG_MORE;
 424                 err = do_sendpage(sock, *ppage, base, len, flags);
 425                 if (remainder == 0 || err != len)
 426                         break;
 427                 sent += err;
 428                 ppage++;
 429                 base = 0;
 430         }
 431         if (sent == 0)
 432                 return err;
 433         if (err > 0)
 434                 sent += err;
 435         return sent;
 436 }
 437
 438 /**
 439  * xs_sendpages - write pages directly to a socket
 440  * @sock: socket to send on
 441  * @addr: UDP only -- address of destination
 442  * @addrlen: UDP only -- length of destination address
 443  * @xdr: buffer containing this request
 444  * @base: starting position in the buffer
 445  * @zerocopy: true if it is safe to use sendpage()
 446  *
 447  */
 448 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy)
 449 {
 450         unsigned int remainder = xdr->len - base;
 451         int err, sent = 0;
 452
 453         if (unlikely(!sock))
 454                 return -ENOTSOCK;
 455
 456         clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 457         if (base != 0) {
 458                 addr = NULL;
 459                 addrlen = 0;
 460         }
 461
 462         if (base < xdr->head[0].iov_len || addr != NULL) {
 463                 unsigned int len = xdr->head[0].iov_len - base;
 464                 remainder -= len;
 465                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 466                 if (remainder == 0 || err != len)
 467                         goto out;
 468                 sent += err;
 469                 base = 0;
 470         } else
 471                 base -= xdr->head[0].iov_len;
 472
 473         if (base < xdr->page_len) {
 474                 unsigned int len = xdr->page_len - base;
 475                 remainder -= len;
 476                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy);
 477                 if (remainder == 0 || err != len)
 478                         goto out;
 479                 sent += err;
 480                 base = 0;
 481         } else
 482                 base -= xdr->page_len;
 483
 484         if (base >= xdr->tail[0].iov_len)
 485                 return sent;
 486         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 487 out:
 488         if (sent == 0)
 489                 return err;
 490         if (err > 0)
 491                 sent += err;
 492         return sent;
 493 }
 494
 495 static void xs_nospace_callback(struct rpc_task *task)
 496 {
 497         struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 498
 499         transport->inet->sk_write_pending--;
 500         clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 501 }
 502
 503 /**
 504  * xs_nospace - place task on wait queue if transmit was incomplete
 505  * @task: task to put to sleep
 506  *
 507  */
 508 static int xs_nospace(struct rpc_task *task)
 509 {
 510         struct rpc_rqst *req = task->tk_rqstp;
 511         struct rpc_xprt *xprt = req->rq_xprt;
 512         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 513         struct sock *sk = transport->inet;
 514         int ret = -EAGAIN;
 515
 516         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 517                         task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 518                         req->rq_slen);
 519
 520         /* Protect against races with write_space */
 521         spin_lock_bh(&xprt->transport_lock);
 522
 523         /* Don't race with disconnect */
 524         if (xprt_connected(xprt)) {
 525                 if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
 526                         /*
 527                          * Notify TCP that we're limited by the application
 528                          * window size
 529                          */
 530                         set_bit(SOCK_NOSPACE, &transport->sock->flags);
 531                         sk->sk_write_pending++;
 532                         /* ...and wait for more buffer space */
 533                         xprt_wait_for_buffer_space(task, xs_nospace_callback);
 534                 }
 535         } else {
 536                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 537                 ret = -ENOTCONN;
 538         }
 539
 540         spin_unlock_bh(&xprt->transport_lock);
 541
 542         /* Race breaker in case memory is freed before above code is called */
 543         sk->sk_write_space(sk);
 544         return ret;
 545 }
 546
 547 /*
 548  * Construct a stream transport record marker in @buf.
 549  */
 550 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 551 {
 552         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 553         rpc_fraghdr *base = buf->head[0].iov_base;
 554         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 555 }
 556
 557 /**
 558  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 559  * @task: RPC task that manages the state of an RPC request
 560  *
 561  * Return values:
 562  *        0:    The request has been sent
 563  *   EAGAIN:    The socket was blocked, please call again later to
 564  *              complete the request
 565  * ENOTCONN:    Caller needs to invoke connect logic then call again
 566  *    other:    Some other error occured, the request was not sent
 567  */
 568 static int xs_local_send_request(struct rpc_task *task)
 569 {
 570         struct rpc_rqst *req = task->tk_rqstp;
 571         struct rpc_xprt *xprt = req->rq_xprt;
 572         struct sock_xprt *transport =
 573                                 container_of(xprt, struct sock_xprt, xprt);
 574         struct xdr_buf *xdr = &req->rq_snd_buf;
 575         int status;
 576
 577         xs_encode_stream_record_marker(&req->rq_snd_buf);
 578
 579         xs_pktdump("packet data:",
 580                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 581
 582         status = xs_sendpages(transport->sock, NULL, 0,
 583                                                 xdr, req->rq_bytes_sent, true);
 584         dprintk("RPC:       %s(%u) = %d\n",
 585                         __func__, xdr->len - req->rq_bytes_sent, status);
 586         if (likely(status >= 0)) {
 587                 req->rq_bytes_sent += status;
 588                 req->rq_xmit_bytes_sent += status;
 589                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 590                         req->rq_bytes_sent = 0;
 591                         return 0;
 592                 }
 593                 status = -EAGAIN;
 594         }
 595
 596         switch (status) {
 597         case -EAGAIN:
 598                 status = xs_nospace(task);
 599                 break;
 600         default:
 601                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 602                         -status);
 603         case -EPIPE:
 604                 xs_close(xprt);
 605                 status = -ENOTCONN;
 606         }
 607
 608         return status;
 609 }
 610
 611 /**
 612  * xs_udp_send_request - write an RPC request to a UDP socket
 613  * @task: address of RPC task that manages the state of an RPC request
 614  *
 615  * Return values:
 616  *        0:    The request has been sent
 617  *   EAGAIN:    The socket was blocked, please call again later to
 618  *              complete the request
 619  * ENOTCONN:    Caller needs to invoke connect logic then call again
 620  *    other:    Some other error occurred, the request was not sent
 621  */
 622 static int xs_udp_send_request(struct rpc_task *task)
 623 {
 624         struct rpc_rqst *req = task->tk_rqstp;
 625         struct rpc_xprt *xprt = req->rq_xprt;
 626         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 627         struct xdr_buf *xdr = &req->rq_snd_buf;
 628         int status;
 629
 630         xs_pktdump("packet data:",
 631                                 req->rq_svec->iov_base,
 632                                 req->rq_svec->iov_len);
 633
 634         if (!xprt_bound(xprt))
 635                 return -ENOTCONN;
 636         status = xs_sendpages(transport->sock,
 637                               xs_addr(xprt),
 638                               xprt->addrlen, xdr,
 639                               req->rq_bytes_sent, true);
 640
 641         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 642                         xdr->len - req->rq_bytes_sent, status);
 643
 644         if (status >= 0) {
 645                 req->rq_xmit_bytes_sent += status;
 646                 if (status >= req->rq_slen)
 647                         return 0;
 648                 /* Still some bytes left; set up for a retry later. */
 649                 status = -EAGAIN;
 650         }
 651
 652         switch (status) {
 653         case -ENOTSOCK:
 654                 status = -ENOTCONN;
 655                 /* Should we call xs_close() here? */
 656                 break;
 657         case -EAGAIN:
 658                 status = xs_nospace(task);
 659                 break;
 660         default:
 661                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 662                         -status);
 663         case -ENETUNREACH:
 664         case -EPIPE:
 665         case -ECONNREFUSED:
 666                 /* When the server has died, an ICMP port unreachable message
 667                  * prompts ECONNREFUSED. */
 668                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 669         }
 670
 671         return status;
 672 }
 673
 674 /**
 675  * xs_tcp_shutdown - gracefully shut down a TCP socket
 676  * @xprt: transport
 677  *
 678  * Initiates a graceful shutdown of the TCP socket by calling the
 679  * equivalent of shutdown(SHUT_WR);
 680  */
 681 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 682 {
 683         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 684         struct socket *sock = transport->sock;
 685
 686         if (sock != NULL) {
 687                 kernel_sock_shutdown(sock, SHUT_WR);
 688                 trace_rpc_socket_shutdown(xprt, sock);
 689         }
 690 }
 691
 692 /**
 693  * xs_tcp_send_request - write an RPC request to a TCP socket
 694  * @task: address of RPC task that manages the state of an RPC request
 695  *
 696  * Return values:
 697  *        0:    The request has been sent
 698  *   EAGAIN:    The socket was blocked, please call again later to
 699  *              complete the request
 700  * ENOTCONN:    Caller needs to invoke connect logic then call again
 701  *    other:    Some other error occurred, the request was not sent
 702  *
 703  * XXX: In the case of soft timeouts, should we eventually give up
 704  *      if sendmsg is not able to make progress?
 705  */
 706 static int xs_tcp_send_request(struct rpc_task *task)
 707 {
 708         struct rpc_rqst *req = task->tk_rqstp;
 709         struct rpc_xprt *xprt = req->rq_xprt;
 710         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 711         struct xdr_buf *xdr = &req->rq_snd_buf;
 712         bool zerocopy = true;
 713         int status;
 714
 715         xs_encode_stream_record_marker(&req->rq_snd_buf);
 716
 717         xs_pktdump("packet data:",
 718                                 req->rq_svec->iov_base,
 719                                 req->rq_svec->iov_len);
 720         /* Don't use zero copy if this is a resend. If the RPC call
 721          * completes while the socket holds a reference to the pages,
 722          * then we may end up resending corrupted data.
 723          */
 724         if (task->tk_flags & RPC_TASK_SENT)
 725                 zerocopy = false;
 726
 727         /* Continue transmitting the packet/record. We must be careful
 728          * to cope with writespace callbacks arriving _after_ we have
 729          * called sendmsg(). */
 730         while (1) {
 731                 status = xs_sendpages(transport->sock,
 732                                         NULL, 0, xdr, req->rq_bytes_sent,
 733                                         zerocopy);
 734
 735                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 736                                 xdr->len - req->rq_bytes_sent, status);
 737
 738                 if (unlikely(status < 0))
 739                         break;
 740
 741                 /* If we've sent the entire packet, immediately
 742                  * reset the count of bytes sent. */
 743                 req->rq_bytes_sent += status;
 744                 req->rq_xmit_bytes_sent += status;
 745                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 746                         req->rq_bytes_sent = 0;
 747                         return 0;
 748                 }
 749
 750                 if (status != 0)
 751                         continue;
 752                 status = -EAGAIN;
 753                 break;
 754         }
 755
 756         switch (status) {
 757         case -ENOTSOCK:
 758                 status = -ENOTCONN;
 759                 /* Should we call xs_close() here? */
 760                 break;
 761         case -EAGAIN:
 762                 status = xs_nospace(task);
 763                 break;
 764         default:
 765                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 766                         -status);
 767         case -ECONNRESET:
 768                 xs_tcp_shutdown(xprt);
 769         case -ECONNREFUSED:
 770         case -ENOTCONN:
 771         case -EPIPE:
 772                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 773         }
 774
 775         return status;
 776 }
 777
 778 /**
 779  * xs_tcp_release_xprt - clean up after a tcp transmission
 780  * @xprt: transport
 781  * @task: rpc task
 782  *
 783  * This cleans up if an error causes us to abort the transmission of a request.
 784  * In this case, the socket may need to be reset in order to avoid confusing
 785  * the server.
 786  */
 787 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 788 {
 789         struct rpc_rqst *req;
 790
 791         if (task != xprt->snd_task)
 792                 return;
 793         if (task == NULL)
 794                 goto out_release;
 795         req = task->tk_rqstp;
 796         if (req == NULL)
 797                 goto out_release;
 798         if (req->rq_bytes_sent == 0)
 799                 goto out_release;
 800         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 801                 goto out_release;
 802         set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 803 out_release:
 804         xprt_release_xprt(xprt, task);
 805 }
 806
 807 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 808 {
 809         transport->old_data_ready = sk->sk_data_ready;
 810         transport->old_state_change = sk->sk_state_change;
 811         transport->old_write_space = sk->sk_write_space;
 812         transport->old_error_report = sk->sk_error_report;
 813 }
 814
 815 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 816 {
 817         sk->sk_data_ready = transport->old_data_ready;
 818         sk->sk_state_change = transport->old_state_change;
 819         sk->sk_write_space = transport->old_write_space;
 820         sk->sk_error_report = transport->old_error_report;
 821 }
 822
 823 /**
 824  * xs_error_report - callback to handle TCP socket state errors
 825  * @sk: socket
 826  *
 827  * Note: we don't call sock_error() since there may be a rpc_task
 828  * using the socket, and so we don't want to clear sk->sk_err.
 829  */
 830 static void xs_error_report(struct sock *sk)
 831 {
 832         struct rpc_xprt *xprt;
 833         int err;
 834
 835         read_lock_bh(&sk->sk_callback_lock);
 836         if (!(xprt = xprt_from_sock(sk)))
 837                 goto out;
 838
 839         err = -sk->sk_err;
 840         if (err == 0)
 841                 goto out;
 842         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
 843                         xprt, -err);
 844         trace_rpc_socket_error(xprt, sk->sk_socket, err);
 845         xprt_wake_pending_tasks(xprt, err);
 846  out:
 847         read_unlock_bh(&sk->sk_callback_lock);
 848 }
 849
 850 static void xs_reset_transport(struct sock_xprt *transport)
 851 {
 852         struct socket *sock = transport->sock;
 853         struct sock *sk = transport->inet;
 854
 855         if (sk == NULL)
 856                 return;
 857
 858         transport->srcport = 0;
 859
 860         write_lock_bh(&sk->sk_callback_lock);
 861         transport->inet = NULL;
 862         transport->sock = NULL;
 863
 864         sk->sk_user_data = NULL;
 865
 866         xs_restore_old_callbacks(transport, sk);
 867         write_unlock_bh(&sk->sk_callback_lock);
 868
 869         trace_rpc_socket_close(&transport->xprt, sock);
 870         sock_release(sock);
 871 }
 872
 873 /**
 874  * xs_close - close a socket
 875  * @xprt: transport
 876  *
 877  * This is used when all requests are complete; ie, no DRC state remains
 878  * on the server we want to save.
 879  *
 880  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 881  * xs_reset_transport() zeroing the socket from underneath a writer.
 882  */
 883 static void xs_close(struct rpc_xprt *xprt)
 884 {
 885         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 886
 887         dprintk("RPC:       xs_close xprt %p\n", xprt);
 888
 889         cancel_delayed_work_sync(&transport->connect_worker);
 890
 891         xs_reset_transport(transport);
 892         xprt->reestablish_timeout = 0;
 893
 894         smp_mb__before_atomic();
 895         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 896         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 897         clear_bit(XPRT_CLOSING, &xprt->state);
 898         smp_mb__after_atomic();
 899         xprt_disconnect_done(xprt);
 900 }
 901
 902 static void xs_tcp_close(struct rpc_xprt *xprt)
 903 {
 904         if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 905                 xs_close(xprt);
 906         else
 907                 xs_tcp_shutdown(xprt);
 908 }
 909
 910 static void xs_xprt_free(struct rpc_xprt *xprt)
 911 {
 912         xs_free_peer_addresses(xprt);
 913         xprt_free(xprt);
 914 }
 915
 916 /**
 917  * xs_destroy - prepare to shutdown a transport
 918  * @xprt: doomed transport
 919  *
 920  */
 921 static void xs_destroy(struct rpc_xprt *xprt)
 922 {
 923         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 924
 925         xs_close(xprt);
 926         xs_xprt_free(xprt);
 927         module_put(THIS_MODULE);
 928 }
 929
 930 static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 931 {
 932         struct xdr_skb_reader desc = {
 933                 .skb            = skb,
 934                 .offset         = sizeof(rpc_fraghdr),
 935                 .count          = skb->len - sizeof(rpc_fraghdr),
 936         };
 937
 938         if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
 939                 return -1;
 940         if (desc.count)
 941                 return -1;
 942         return 0;
 943 }
 944
 945 /**
 946  * xs_local_data_ready - "data ready" callback for AF_LOCAL sockets
 947  * @sk: socket with data to read
 948  * @len: how much data to read
 949  *
 950  * Currently this assumes we can read the whole reply in a single gulp.
 951  */
 952 static void xs_local_data_ready(struct sock *sk)
 953 {
 954         struct rpc_task *task;
 955         struct rpc_xprt *xprt;
 956         struct rpc_rqst *rovr;
 957         struct sk_buff *skb;
 958         int err, repsize, copied;
 959         u32 _xid;
 960         __be32 *xp;
 961
 962         read_lock_bh(&sk->sk_callback_lock);
 963         dprintk("RPC:       %s...\n", __func__);
 964         xprt = xprt_from_sock(sk);
 965         if (xprt == NULL)
 966                 goto out;
 967
 968         skb = skb_recv_datagram(sk, 0, 1, &err);
 969         if (skb == NULL)
 970                 goto out;
 971
 972         repsize = skb->len - sizeof(rpc_fraghdr);
 973         if (repsize < 4) {
 974                 dprintk("RPC:       impossible RPC reply size %d\n", repsize);
 975                 goto dropit;
 976         }
 977
 978         /* Copy the XID from the skb... */
 979         xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid);
 980         if (xp == NULL)
 981                 goto dropit;
 982
 983         /* Look up and lock the request corresponding to the given XID */
 984         spin_lock(&xprt->transport_lock);
 985         rovr = xprt_lookup_rqst(xprt, *xp);
 986         if (!rovr)
 987                 goto out_unlock;
 988         task = rovr->rq_task;
 989
 990         copied = rovr->rq_private_buf.buflen;
 991         if (copied > repsize)
 992                 copied = repsize;
 993
 994         if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 995                 dprintk("RPC:       sk_buff copy failed\n");
 996                 goto out_unlock;
 997         }
 998
 999         xprt_complete_rqst(task, copied);
1000
1001  out_unlock:
1002         spin_unlock(&xprt->transport_lock);
1003  dropit:
1004         skb_free_datagram(sk, skb);
1005  out:
1006         read_unlock_bh(&sk->sk_callback_lock);
1007 }
1008
1009 /**
1010  * xs_udp_data_ready - "data ready" callback for UDP sockets
1011  * @sk: socket with data to read
1012  * @len: how much data to read
1013  *
1014  */
1015 static void xs_udp_data_ready(struct sock *sk)
1016 {
1017         struct rpc_task *task;
1018         struct rpc_xprt *xprt;
1019         struct rpc_rqst *rovr;
1020         struct sk_buff *skb;
1021         int err, repsize, copied;
1022         u32 _xid;
1023         __be32 *xp;
1024
1025         read_lock_bh(&sk->sk_callback_lock);
1026         dprintk("RPC:       xs_udp_data_ready...\n");
1027         if (!(xprt = xprt_from_sock(sk)))
1028                 goto out;
1029
1030         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
1031                 goto out;
1032
1033         repsize = skb->len - sizeof(struct udphdr);
1034         if (repsize < 4) {
1035                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1036                 goto dropit;
1037         }
1038
1039         /* Copy the XID from the skb... */
1040         xp = skb_header_pointer(skb, sizeof(struct udphdr),
1041                                 sizeof(_xid), &_xid);
1042         if (xp == NULL)
1043                 goto dropit;
1044
1045         /* Look up and lock the request corresponding to the given XID */
1046         spin_lock(&xprt->transport_lock);
1047         rovr = xprt_lookup_rqst(xprt, *xp);
1048         if (!rovr)
1049                 goto out_unlock;
1050         task = rovr->rq_task;
1051
1052         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1053                 copied = repsize;
1054
1055         /* Suck it into the iovec, verify checksum if not done by hw. */
1056         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1057                 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
1058                 goto out_unlock;
1059         }
1060
1061         UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
1062
1063         xprt_adjust_cwnd(xprt, task, copied);
1064         xprt_complete_rqst(task, copied);
1065
1066  out_unlock:
1067         spin_unlock(&xprt->transport_lock);
1068  dropit:
1069         skb_free_datagram(sk, skb);
1070  out:
1071         read_unlock_bh(&sk->sk_callback_lock);
1072 }
1073
1074 /*
1075  * Helper function to force a TCP close if the server is sending
1076  * junk and/or it has put us in CLOSE_WAIT
1077  */
1078 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1079 {
1080         set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1081         xprt_force_disconnect(xprt);
1082 }
1083
1084 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
1085 {
1086         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1087         size_t len, used;
1088         char *p;
1089
1090         p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
1091         len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
1092         used = xdr_skb_read_bits(desc, p, len);
1093         transport->tcp_offset += used;
1094         if (used != len)
1095                 return;
1096
1097         transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
1098         if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
1099                 transport->tcp_flags |= TCP_RCV_LAST_FRAG;
1100         else
1101                 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
1102         transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
1103
1104         transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
1105         transport->tcp_offset = 0;
1106
1107         /* Sanity check of the record length */
1108         if (unlikely(transport->tcp_reclen < 8)) {
1109                 dprintk("RPC:       invalid TCP record fragment length\n");
1110                 xs_tcp_force_close(xprt);
1111                 return;
1112         }
1113         dprintk("RPC:       reading TCP record fragment of length %d\n",
1114                         transport->tcp_reclen);
1115 }
1116
1117 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
1118 {
1119         if (transport->tcp_offset == transport->tcp_reclen) {
1120                 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
1121                 transport->tcp_offset = 0;
1122                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
1123                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1124                         transport->tcp_flags |= TCP_RCV_COPY_XID;
1125                         transport->tcp_copied = 0;
1126                 }
1127         }
1128 }
1129
1130 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1131 {
1132         size_t len, used;
1133         char *p;
1134
1135         len = sizeof(transport->tcp_xid) - transport->tcp_offset;
1136         dprintk("RPC:       reading XID (%Zu bytes)\n", len);
1137         p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
1138         used = xdr_skb_read_bits(desc, p, len);
1139         transport->tcp_offset += used;
1140         if (used != len)
1141                 return;
1142         transport->tcp_flags &= ~TCP_RCV_COPY_XID;
1143         transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
1144         transport->tcp_copied = 4;
1145         dprintk("RPC:       reading %s XID %08x\n",
1146                         (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
1147                                                               : "request with",
1148                         ntohl(transport->tcp_xid));
1149         xs_tcp_check_fraghdr(transport);
1150 }
1151
1152 static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
1153                                        struct xdr_skb_reader *desc)
1154 {
1155         size_t len, used;
1156         u32 offset;
1157         char *p;
1158
1159         /*
1160          * We want transport->tcp_offset to be 8 at the end of this routine
1161          * (4 bytes for the xid and 4 bytes for the call/reply flag).
1162          * When this function is called for the first time,
1163          * transport->tcp_offset is 4 (after having already read the xid).
1164          */
1165         offset = transport->tcp_offset - sizeof(transport->tcp_xid);
1166         len = sizeof(transport->tcp_calldir) - offset;
1167         dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
1168         p = ((char *) &transport->tcp_calldir) + offset;
1169         used = xdr_skb_read_bits(desc, p, len);
1170         transport->tcp_offset += used;
1171         if (used != len)
1172                 return;
1173         transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
1174         /*
1175          * We don't yet have the XDR buffer, so we will write the calldir
1176          * out after we get the buffer from the 'struct rpc_rqst'
1177          */
1178         switch (ntohl(transport->tcp_calldir)) {
1179         case RPC_REPLY:
1180                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1181                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
1182                 transport->tcp_flags |= TCP_RPC_REPLY;
1183                 break;
1184         case RPC_CALL:
1185                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1186                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
1187                 transport->tcp_flags &= ~TCP_RPC_REPLY;
1188                 break;
1189         default:
1190                 dprintk("RPC:       invalid request message type\n");
1191                 xs_tcp_force_close(&transport->xprt);
1192         }
1193         xs_tcp_check_fraghdr(transport);
1194 }
1195
1196 static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
1197                                      struct xdr_skb_reader *desc,
1198                                      struct rpc_rqst *req)
1199 {
1200         struct sock_xprt *transport =
1201                                 container_of(xprt, struct sock_xprt, xprt);
1202         struct xdr_buf *rcvbuf;
1203         size_t len;
1204         ssize_t r;
1205
1206         rcvbuf = &req->rq_private_buf;
1207
1208         if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
1209                 /*
1210                  * Save the RPC direction in the XDR buffer
1211                  */
1212                 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
1213                         &transport->tcp_calldir,
1214                         sizeof(transport->tcp_calldir));
1215                 transport->tcp_copied += sizeof(transport->tcp_calldir);
1216                 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
1217         }
1218
1219         len = desc->count;
1220         if (len > transport->tcp_reclen - transport->tcp_offset) {
1221                 struct xdr_skb_reader my_desc;
1222
1223                 len = transport->tcp_reclen - transport->tcp_offset;
1224                 memcpy(&my_desc, desc, sizeof(my_desc));
1225                 my_desc.count = len;
1226                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1227                                           &my_desc, xdr_skb_read_bits);
1228                 desc->count -= r;
1229                 desc->offset += r;
1230         } else
1231                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1232                                           desc, xdr_skb_read_bits);
1233
1234         if (r > 0) {
1235                 transport->tcp_copied += r;
1236                 transport->tcp_offset += r;
1237         }
1238         if (r != len) {
1239                 /* Error when copying to the receive buffer,
1240                  * usually because we weren't able to allocate
1241                  * additional buffer pages. All we can do now
1242                  * is turn off TCP_RCV_COPY_DATA, so the request
1243                  * will not receive any additional updates,
1244                  * and time out.
1245                  * Any remaining data from this record will
1246                  * be discarded.
1247                  */
1248                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1249                 dprintk("RPC:       XID %08x truncated request\n",
1250                                 ntohl(transport->tcp_xid));
1251                 dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1252                                 "tcp_offset = %u, tcp_reclen = %u\n",
1253                                 xprt, transport->tcp_copied,
1254                                 transport->tcp_offset, transport->tcp_reclen);
1255                 return;
1256         }
1257
1258         dprintk("RPC:       XID %08x read %Zd bytes\n",
1259                         ntohl(transport->tcp_xid), r);
1260         dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1261                         "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1262                         transport->tcp_offset, transport->tcp_reclen);
1263
1264         if (transport->tcp_copied == req->rq_private_buf.buflen)
1265                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1266         else if (transport->tcp_offset == transport->tcp_reclen) {
1267                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1268                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1269         }
1270 }
1271
1272 /*
1273  * Finds the request corresponding to the RPC xid and invokes the common
1274  * tcp read code to read the data.
1275  */
1276 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1277                                     struct xdr_skb_reader *desc)
1278 {
1279         struct sock_xprt *transport =
1280                                 container_of(xprt, struct sock_xprt, xprt);
1281         struct rpc_rqst *req;
1282
1283         dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1284
1285         /* Find and lock the request corresponding to this xid */
1286         spin_lock(&xprt->transport_lock);
1287         req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1288         if (!req) {
1289                 dprintk("RPC:       XID %08x request not found!\n",
1290                                 ntohl(transport->tcp_xid));
1291                 spin_unlock(&xprt->transport_lock);
1292                 return -1;
1293         }
1294
1295         xs_tcp_read_common(xprt, desc, req);
1296
1297         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1298                 xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1299
1300         spin_unlock(&xprt->transport_lock);
1301         return 0;
1302 }
1303
1304 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1305 /*
1306  * Obtains an rpc_rqst previously allocated and invokes the common
1307  * tcp read code to read the data.  The result is placed in the callback
1308  * queue.
1309  * If we're unable to obtain the rpc_rqst we schedule the closing of the
1310  * connection and return -1.
1311  */
1312 static int xs_tcp_read_callback(struct rpc_xprt *xprt,
1313                                        struct xdr_skb_reader *desc)
1314 {
1315         struct sock_xprt *transport =
1316                                 container_of(xprt, struct sock_xprt, xprt);
1317         struct rpc_rqst *req;
1318
1319         /* Look up and lock the request corresponding to the given XID */
1320         spin_lock(&xprt->transport_lock);
1321         req = xprt_lookup_bc_request(xprt, transport->tcp_xid);
1322         if (req == NULL) {
1323                 spin_unlock(&xprt->transport_lock);
1324                 printk(KERN_WARNING "Callback slot table overflowed\n");
1325                 xprt_force_disconnect(xprt);
1326                 return -1;
1327         }
1328
1329         dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1330         xs_tcp_read_common(xprt, desc, req);
1331
1332         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1333                 xprt_complete_bc_request(req, transport->tcp_copied);
1334         spin_unlock(&xprt->transport_lock);
1335
1336         return 0;
1337 }
1338
1339 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1340                                         struct xdr_skb_reader *desc)
1341 {
1342         struct sock_xprt *transport =
1343                                 container_of(xprt, struct sock_xprt, xprt);
1344
1345         return (transport->tcp_flags & TCP_RPC_REPLY) ?
1346                 xs_tcp_read_reply(xprt, desc) :
1347                 xs_tcp_read_callback(xprt, desc);
1348 }
1349 #else
1350 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1351                                         struct xdr_skb_reader *desc)
1352 {
1353         return xs_tcp_read_reply(xprt, desc);
1354 }
1355 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1356
1357 /*
1358  * Read data off the transport.  This can be either an RPC_CALL or an
1359  * RPC_REPLY.  Relay the processing to helper functions.
1360  */
1361 static void xs_tcp_read_data(struct rpc_xprt *xprt,
1362                                     struct xdr_skb_reader *desc)
1363 {
1364         struct sock_xprt *transport =
1365                                 container_of(xprt, struct sock_xprt, xprt);
1366
1367         if (_xs_tcp_read_data(xprt, desc) == 0)
1368                 xs_tcp_check_fraghdr(transport);
1369         else {
1370                 /*
1371                  * The transport_lock protects the request handling.
1372                  * There's no need to hold it to update the tcp_flags.
1373                  */
1374                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1375         }
1376 }
1377
1378 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1379 {
1380         size_t len;
1381
1382         len = transport->tcp_reclen - transport->tcp_offset;
1383         if (len > desc->count)
1384                 len = desc->count;
1385         desc->count -= len;
1386         desc->offset += len;
1387         transport->tcp_offset += len;
1388         dprintk("RPC:       discarded %Zu bytes\n", len);
1389         xs_tcp_check_fraghdr(transport);
1390 }
1391
1392 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1393 {
1394         struct rpc_xprt *xprt = rd_desc->arg.data;
1395         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1396         struct xdr_skb_reader desc = {
1397                 .skb    = skb,
1398                 .offset = offset,
1399                 .count  = len,
1400         };
1401
1402         dprintk("RPC:       xs_tcp_data_recv started\n");
1403         do {
1404                 /* Read in a new fragment marker if necessary */
1405                 /* Can we ever really expect to get completely empty fragments? */
1406                 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1407                         xs_tcp_read_fraghdr(xprt, &desc);
1408                         continue;
1409                 }
1410                 /* Read in the xid if necessary */
1411                 if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1412                         xs_tcp_read_xid(transport, &desc);
1413                         continue;
1414                 }
1415                 /* Read in the call/reply flag */
1416                 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1417                         xs_tcp_read_calldir(transport, &desc);
1418                         continue;
1419                 }
1420                 /* Read in the request data */
1421                 if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1422                         xs_tcp_read_data(xprt, &desc);
1423                         continue;
1424                 }
1425                 /* Skip over any trailing bytes on short reads */
1426                 xs_tcp_read_discard(transport, &desc);
1427         } while (desc.count);
1428         dprintk("RPC:       xs_tcp_data_recv done\n");
1429         return len - desc.count;
1430 }
1431
1432 /**
1433  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1434  * @sk: socket with data to read
1435  * @bytes: how much data to read
1436  *
1437  */
1438 static void xs_tcp_data_ready(struct sock *sk)
1439 {
1440         struct rpc_xprt *xprt;
1441         read_descriptor_t rd_desc;
1442         int read;
1443
1444         dprintk("RPC:       xs_tcp_data_ready...\n");
1445
1446         read_lock_bh(&sk->sk_callback_lock);
1447         if (!(xprt = xprt_from_sock(sk)))
1448                 goto out;
1449         /* Any data means we had a useful conversation, so
1450          * the we don't need to delay the next reconnect
1451          */
1452         if (xprt->reestablish_timeout)
1453                 xprt->reestablish_timeout = 0;
1454
1455         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1456         rd_desc.arg.data = xprt;
1457         do {
1458                 rd_desc.count = 65536;
1459                 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1460         } while (read > 0);
1461 out:
1462         read_unlock_bh(&sk->sk_callback_lock);
1463 }
1464
1465 /*
1466  * Do the equivalent of linger/linger2 handling for dealing with
1467  * broken servers that don't close the socket in a timely
1468  * fashion
1469  */
1470 static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1471                 unsigned long timeout)
1472 {
1473         struct sock_xprt *transport;
1474
1475         if (xprt_test_and_set_connecting(xprt))
1476                 return;
1477         set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1478         transport = container_of(xprt, struct sock_xprt, xprt);
1479         queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1480                            timeout);
1481 }
1482
1483 static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1484 {
1485         struct sock_xprt *transport;
1486
1487         transport = container_of(xprt, struct sock_xprt, xprt);
1488
1489         if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1490             !cancel_delayed_work(&transport->connect_worker))
1491                 return;
1492         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1493         xprt_clear_connecting(xprt);
1494 }
1495
1496 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1497 {
1498         smp_mb__before_atomic();
1499         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1500         clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1501         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1502         clear_bit(XPRT_CLOSING, &xprt->state);
1503         smp_mb__after_atomic();
1504 }
1505
1506 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1507 {
1508         xs_sock_reset_connection_flags(xprt);
1509         /* Mark transport as closed and wake up all pending tasks */
1510         xprt_disconnect_done(xprt);
1511 }
1512
1513 /**
1514  * xs_tcp_state_change - callback to handle TCP socket state changes
1515  * @sk: socket whose state has changed
1516  *
1517  */
1518 static void xs_tcp_state_change(struct sock *sk)
1519 {
1520         struct rpc_xprt *xprt;
1521
1522         read_lock_bh(&sk->sk_callback_lock);
1523         if (!(xprt = xprt_from_sock(sk)))
1524                 goto out;
1525         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1526         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1527                         sk->sk_state, xprt_connected(xprt),
1528                         sock_flag(sk, SOCK_DEAD),
1529                         sock_flag(sk, SOCK_ZAPPED),
1530                         sk->sk_shutdown);
1531
1532         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1533         switch (sk->sk_state) {
1534         case TCP_ESTABLISHED:
1535                 spin_lock(&xprt->transport_lock);
1536                 if (!xprt_test_and_set_connected(xprt)) {
1537                         struct sock_xprt *transport = container_of(xprt,
1538                                         struct sock_xprt, xprt);
1539
1540                         /* Reset TCP record info */
1541                         transport->tcp_offset = 0;
1542                         transport->tcp_reclen = 0;
1543                         transport->tcp_copied = 0;
1544                         transport->tcp_flags =
1545                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1546                         xprt->connect_cookie++;
1547
1548                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1549                 }
1550                 spin_unlock(&xprt->transport_lock);
1551                 break;
1552         case TCP_FIN_WAIT1:
1553                 /* The client initiated a shutdown of the socket */
1554                 xprt->connect_cookie++;
1555                 xprt->reestablish_timeout = 0;
1556                 set_bit(XPRT_CLOSING, &xprt->state);
1557                 smp_mb__before_atomic();
1558                 clear_bit(XPRT_CONNECTED, &xprt->state);
1559                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1560                 smp_mb__after_atomic();
1561                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1562                 break;
1563         case TCP_CLOSE_WAIT:
1564                 /* The server initiated a shutdown of the socket */
1565                 xprt->connect_cookie++;
1566                 clear_bit(XPRT_CONNECTED, &xprt->state);
1567                 xs_tcp_force_close(xprt);
1568         case TCP_CLOSING:
1569                 /*
1570                  * If the server closed down the connection, make sure that
1571                  * we back off before reconnecting
1572                  */
1573                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1574                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1575                 break;
1576         case TCP_LAST_ACK:
1577                 set_bit(XPRT_CLOSING, &xprt->state);
1578                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1579                 smp_mb__before_atomic();
1580                 clear_bit(XPRT_CONNECTED, &xprt->state);
1581                 smp_mb__after_atomic();
1582                 break;
1583         case TCP_CLOSE:
1584                 xs_tcp_cancel_linger_timeout(xprt);
1585                 xs_sock_mark_closed(xprt);
1586         }
1587  out:
1588         read_unlock_bh(&sk->sk_callback_lock);
1589 }
1590
1591 static void xs_write_space(struct sock *sk)
1592 {
1593         struct socket *sock;
1594         struct rpc_xprt *xprt;
1595
1596         if (unlikely(!(sock = sk->sk_socket)))
1597                 return;
1598         clear_bit(SOCK_NOSPACE, &sock->flags);
1599
1600         if (unlikely(!(xprt = xprt_from_sock(sk))))
1601                 return;
1602         if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1603                 return;
1604
1605         xprt_write_space(xprt);
1606 }
1607
1608 /**
1609  * xs_udp_write_space - callback invoked when socket buffer space
1610  *                             becomes available
1611  * @sk: socket whose state has changed
1612  *
1613  * Called when more output buffer space is available for this socket.
1614  * We try not to wake our writers until they can make "significant"
1615  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1616  * with a bunch of small requests.
1617  */
1618 static void xs_udp_write_space(struct sock *sk)
1619 {
1620         read_lock_bh(&sk->sk_callback_lock);
1621
1622         /* from net/core/sock.c:sock_def_write_space */
1623         if (sock_writeable(sk))
1624                 xs_write_space(sk);
1625
1626         read_unlock_bh(&sk->sk_callback_lock);
1627 }
1628
1629 /**
1630  * xs_tcp_write_space - callback invoked when socket buffer space
1631  *                             becomes available
1632  * @sk: socket whose state has changed
1633  *
1634  * Called when more output buffer space is available for this socket.
1635  * We try not to wake our writers until they can make "significant"
1636  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1637  * with a bunch of small requests.
1638  */
1639 static void xs_tcp_write_space(struct sock *sk)
1640 {
1641         read_lock_bh(&sk->sk_callback_lock);
1642
1643         /* from net/core/stream.c:sk_stream_write_space */
1644         if (sk_stream_is_writeable(sk))
1645                 xs_write_space(sk);
1646
1647         read_unlock_bh(&sk->sk_callback_lock);
1648 }
1649
1650 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1651 {
1652         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1653         struct sock *sk = transport->inet;
1654
1655         if (transport->rcvsize) {
1656                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1657                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1658         }
1659         if (transport->sndsize) {
1660                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1661                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1662                 sk->sk_write_space(sk);
1663         }
1664 }
1665
1666 /**
1667  * xs_udp_set_buffer_size - set send and receive limits
1668  * @xprt: generic transport
1669  * @sndsize: requested size of send buffer, in bytes
1670  * @rcvsize: requested size of receive buffer, in bytes
1671  *
1672  * Set socket send and receive buffer size limits.
1673  */
1674 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1675 {
1676         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1677
1678         transport->sndsize = 0;
1679         if (sndsize)
1680                 transport->sndsize = sndsize + 1024;
1681         transport->rcvsize = 0;
1682         if (rcvsize)
1683                 transport->rcvsize = rcvsize + 1024;
1684
1685         xs_udp_do_set_buffer_size(xprt);
1686 }
1687
1688 /**
1689  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1690  * @task: task that timed out
1691  *
1692  * Adjust the congestion window after a retransmit timeout has occurred.
1693  */
1694 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1695 {
1696         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1697 }
1698
1699 static unsigned short xs_get_random_port(void)
1700 {
1701         unsigned short range = xprt_max_resvport - xprt_min_resvport;
1702         unsigned short rand = (unsigned short) prandom_u32() % range;
1703         return rand + xprt_min_resvport;
1704 }
1705
1706 /**
1707  * xs_set_port - reset the port number in the remote endpoint address
1708  * @xprt: generic transport
1709  * @port: new port number
1710  *
1711  */
1712 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1713 {
1714         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1715
1716         rpc_set_port(xs_addr(xprt), port);
1717         xs_update_peer_port(xprt);
1718 }
1719
1720 static unsigned short xs_get_srcport(struct sock_xprt *transport)
1721 {
1722         unsigned short port = transport->srcport;
1723
1724         if (port == 0 && transport->xprt.resvport)
1725                 port = xs_get_random_port();
1726         return port;
1727 }
1728
1729 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1730 {
1731         if (transport->srcport != 0)
1732                 transport->srcport = 0;
1733         if (!transport->xprt.resvport)
1734                 return 0;
1735         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1736                 return xprt_max_resvport;
1737         return --port;
1738 }
1739 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1740 {
1741         struct sockaddr_storage myaddr;
1742         int err, nloop = 0;
1743         unsigned short port = xs_get_srcport(transport);
1744         unsigned short last;
1745
1746         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1747         do {
1748                 rpc_set_port((struct sockaddr *)&myaddr, port);
1749                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1750                                 transport->xprt.addrlen);
1751                 if (port == 0)
1752                         break;
1753                 if (err == 0) {
1754                         transport->srcport = port;
1755                         break;
1756                 }
1757                 last = port;
1758                 port = xs_next_srcport(transport, port);
1759                 if (port > last)
1760                         nloop++;
1761         } while (err == -EADDRINUSE && nloop != 2);
1762
1763         if (myaddr.ss_family == AF_INET)
1764                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1765                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1766                                 port, err ? "failed" : "ok", err);
1767         else
1768                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1769                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1770                                 port, err ? "failed" : "ok", err);
1771         return err;
1772 }
1773
1774 /*
1775  * We don't support autobind on AF_LOCAL sockets
1776  */
1777 static void xs_local_rpcbind(struct rpc_task *task)
1778 {
1779         rcu_read_lock();
1780         xprt_set_bound(rcu_dereference(task->tk_client->cl_xprt));
1781         rcu_read_unlock();
1782 }
1783
1784 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1785 {
1786 }
1787
1788 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1789 static struct lock_class_key xs_key[2];
1790 static struct lock_class_key xs_slock_key[2];
1791
1792 static inline void xs_reclassify_socketu(struct socket *sock)
1793 {
1794         struct sock *sk = sock->sk;
1795
1796         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1797                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1798 }
1799
1800 static inline void xs_reclassify_socket4(struct socket *sock)
1801 {
1802         struct sock *sk = sock->sk;
1803
1804         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1805                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1806 }
1807
1808 static inline void xs_reclassify_socket6(struct socket *sock)
1809 {
1810         struct sock *sk = sock->sk;
1811
1812         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1813                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1814 }
1815
1816 static inline void xs_reclassify_socket(int family, struct socket *sock)
1817 {
1818         WARN_ON_ONCE(sock_owned_by_user(sock->sk));
1819         if (sock_owned_by_user(sock->sk))
1820                 return;
1821
1822         switch (family) {
1823         case AF_LOCAL:
1824                 xs_reclassify_socketu(sock);
1825                 break;
1826         case AF_INET:
1827                 xs_reclassify_socket4(sock);
1828                 break;
1829         case AF_INET6:
1830                 xs_reclassify_socket6(sock);
1831                 break;
1832         }
1833 }
1834 #else
1835 static inline void xs_reclassify_socketu(struct socket *sock)
1836 {
1837 }
1838
1839 static inline void xs_reclassify_socket4(struct socket *sock)
1840 {
1841 }
1842
1843 static inline void xs_reclassify_socket6(struct socket *sock)
1844 {
1845 }
1846
1847 static inline void xs_reclassify_socket(int family, struct socket *sock)
1848 {
1849 }
1850 #endif
1851
1852 static void xs_dummy_setup_socket(struct work_struct *work)
1853 {
1854 }
1855
1856 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1857                 struct sock_xprt *transport, int family, int type, int protocol)
1858 {
1859         struct socket *sock;
1860         int err;
1861
1862         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1863         if (err < 0) {
1864                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1865                                 protocol, -err);
1866                 goto out;
1867         }
1868         xs_reclassify_socket(family, sock);
1869
1870         err = xs_bind(transport, sock);
1871         if (err) {
1872                 sock_release(sock);
1873                 goto out;
1874         }
1875
1876         return sock;
1877 out:
1878         return ERR_PTR(err);
1879 }
1880
1881 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1882                                       struct socket *sock)
1883 {
1884         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1885                                                                         xprt);
1886
1887         if (!transport->inet) {
1888                 struct sock *sk = sock->sk;
1889
1890                 write_lock_bh(&sk->sk_callback_lock);
1891
1892                 xs_save_old_callbacks(transport, sk);
1893
1894                 sk->sk_user_data = xprt;
1895                 sk->sk_data_ready = xs_local_data_ready;
1896                 sk->sk_write_space = xs_udp_write_space;
1897                 sk->sk_error_report = xs_error_report;
1898                 sk->sk_allocation = GFP_ATOMIC;
1899
1900                 xprt_clear_connected(xprt);
1901
1902                 /* Reset to new socket */
1903                 transport->sock = sock;
1904                 transport->inet = sk;
1905
1906                 write_unlock_bh(&sk->sk_callback_lock);
1907         }
1908
1909         /* Tell the socket layer to start connecting... */
1910         xprt->stat.connect_count++;
1911         xprt->stat.connect_start = jiffies;
1912         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1913 }
1914
1915 /**
1916  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1917  * @xprt: RPC transport to connect
1918  * @transport: socket transport to connect
1919  * @create_sock: function to create a socket of the correct type
1920  */
1921 static int xs_local_setup_socket(struct sock_xprt *transport)
1922 {
1923         struct rpc_xprt *xprt = &transport->xprt;
1924         struct socket *sock;
1925         int status = -EIO;
1926
1927         current->flags |= PF_FSTRANS;
1928
1929         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1930         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1931                                         SOCK_STREAM, 0, &sock, 1);
1932         if (status < 0) {
1933                 dprintk("RPC:       can't create AF_LOCAL "
1934                         "transport socket (%d).\n", -status);
1935                 goto out;
1936         }
1937         xs_reclassify_socketu(sock);
1938
1939         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1940                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1941
1942         status = xs_local_finish_connecting(xprt, sock);
1943         trace_rpc_socket_connect(xprt, sock, status);
1944         switch (status) {
1945         case 0:
1946                 dprintk("RPC:       xprt %p connected to %s\n",
1947                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1948                 xprt_set_connected(xprt);
1949                 break;
1950         case -ENOENT:
1951                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1952                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1953                 break;
1954         case -ECONNREFUSED:
1955                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1956                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1957                 break;
1958         default:
1959                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1960                                 __func__, -status,
1961                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1962         }
1963
1964 out:
1965         xprt_clear_connecting(xprt);
1966         xprt_wake_pending_tasks(xprt, status);
1967         current->flags &= ~PF_FSTRANS;
1968         return status;
1969 }
1970
1971 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1972 {
1973         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1974         int ret;
1975
1976          if (RPC_IS_ASYNC(task)) {
1977                 /*
1978                  * We want the AF_LOCAL connect to be resolved in the
1979                  * filesystem namespace of the process making the rpc
1980                  * call.  Thus we connect synchronously.
1981                  *
1982                  * If we want to support asynchronous AF_LOCAL calls,
1983                  * we'll need to figure out how to pass a namespace to
1984                  * connect.
1985                  */
1986                 rpc_exit(task, -ENOTCONN);
1987                 return;
1988         }
1989         ret = xs_local_setup_socket(transport);
1990         if (ret && !RPC_IS_SOFTCONN(task))
1991                 msleep_interruptible(15000);
1992 }
1993
1994 #ifdef CONFIG_SUNRPC_SWAP
1995 static void xs_set_memalloc(struct rpc_xprt *xprt)
1996 {
1997         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1998                         xprt);
1999
2000         if (xprt->swapper)
2001                 sk_set_memalloc(transport->inet);
2002 }
2003
2004 /**
2005  * xs_swapper - Tag this transport as being used for swap.
2006  * @xprt: transport to tag
2007  * @enable: enable/disable
2008  *
2009  */
2010 int xs_swapper(struct rpc_xprt *xprt, int enable)
2011 {
2012         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2013                         xprt);
2014         int err = 0;
2015
2016         if (enable) {
2017                 xprt->swapper++;
2018                 xs_set_memalloc(xprt);
2019         } else if (xprt->swapper) {
2020                 xprt->swapper--;
2021                 sk_clear_memalloc(transport->inet);
2022         }
2023
2024         return err;
2025 }
2026 EXPORT_SYMBOL_GPL(xs_swapper);
2027 #else
2028 static void xs_set_memalloc(struct rpc_xprt *xprt)
2029 {
2030 }
2031 #endif
2032
2033 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2034 {
2035         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2036
2037         if (!transport->inet) {
2038                 struct sock *sk = sock->sk;
2039
2040                 write_lock_bh(&sk->sk_callback_lock);
2041
2042                 xs_save_old_callbacks(transport, sk);
2043
2044                 sk->sk_user_data = xprt;
2045                 sk->sk_data_ready = xs_udp_data_ready;
2046                 sk->sk_write_space = xs_udp_write_space;
2047                 sk->sk_allocation = GFP_ATOMIC;
2048
2049                 xprt_set_connected(xprt);
2050
2051                 /* Reset to new socket */
2052                 transport->sock = sock;
2053                 transport->inet = sk;
2054
2055                 xs_set_memalloc(xprt);
2056
2057                 write_unlock_bh(&sk->sk_callback_lock);
2058         }
2059         xs_udp_do_set_buffer_size(xprt);
2060 }
2061
2062 static void xs_udp_setup_socket(struct work_struct *work)
2063 {
2064         struct sock_xprt *transport =
2065                 container_of(work, struct sock_xprt, connect_worker.work);
2066         struct rpc_xprt *xprt = &transport->xprt;
2067         struct socket *sock = transport->sock;
2068         int status = -EIO;
2069
2070         current->flags |= PF_FSTRANS;
2071
2072         /* Start by resetting any existing state */
2073         xs_reset_transport(transport);
2074         sock = xs_create_sock(xprt, transport,
2075                         xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
2076         if (IS_ERR(sock))
2077                 goto out;
2078
2079         dprintk("RPC:       worker connecting xprt %p via %s to "
2080                                 "%s (port %s)\n", xprt,
2081                         xprt->address_strings[RPC_DISPLAY_PROTO],
2082                         xprt->address_strings[RPC_DISPLAY_ADDR],
2083                         xprt->address_strings[RPC_DISPLAY_PORT]);
2084
2085         xs_udp_finish_connecting(xprt, sock);
2086         trace_rpc_socket_connect(xprt, sock, 0);
2087         status = 0;
2088 out:
2089         xprt_clear_connecting(xprt);
2090         xprt_wake_pending_tasks(xprt, status);
2091         current->flags &= ~PF_FSTRANS;
2092 }
2093
2094 /*
2095  * We need to preserve the port number so the reply cache on the server can
2096  * find our cached RPC replies when we get around to reconnecting.
2097  */
2098 static void xs_abort_connection(struct sock_xprt *transport)
2099 {
2100         int result;
2101         struct sockaddr any;
2102
2103         dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
2104
2105         /*
2106          * Disconnect the transport socket by doing a connect operation
2107          * with AF_UNSPEC.  This should return immediately...
2108          */
2109         memset(&any, 0, sizeof(any));
2110         any.sa_family = AF_UNSPEC;
2111         result = kernel_connect(transport->sock, &any, sizeof(any), 0);
2112         trace_rpc_socket_reset_connection(&transport->xprt,
2113                         transport->sock, result);
2114         if (!result)
2115                 xs_sock_reset_connection_flags(&transport->xprt);
2116         dprintk("RPC:       AF_UNSPEC connect return code %d\n", result);
2117 }
2118
2119 static void xs_tcp_reuse_connection(struct sock_xprt *transport)
2120 {
2121         unsigned int state = transport->inet->sk_state;
2122
2123         if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
2124                 /* we don't need to abort the connection if the socket
2125                  * hasn't undergone a shutdown
2126                  */
2127                 if (transport->inet->sk_shutdown == 0)
2128                         return;
2129                 dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
2130                                 __func__, transport->inet->sk_shutdown);
2131         }
2132         if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
2133                 /* we don't need to abort the connection if the socket
2134                  * hasn't undergone a shutdown
2135                  */
2136                 if (transport->inet->sk_shutdown == 0)
2137                         return;
2138                 dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
2139                                 "sk_shutdown set to %d\n",
2140                                 __func__, transport->inet->sk_shutdown);
2141         }
2142         xs_abort_connection(transport);
2143 }
2144
2145 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2146 {
2147         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2148         int ret = -ENOTCONN;
2149
2150         if (!transport->inet) {
2151                 struct sock *sk = sock->sk;
2152                 unsigned int keepidle = xprt->timeout->to_initval / HZ;
2153                 unsigned int keepcnt = xprt->timeout->to_retries + 1;
2154                 unsigned int opt_on = 1;
2155
2156                 /* TCP Keepalive options */
2157                 kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2158                                 (char *)&opt_on, sizeof(opt_on));
2159                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2160                                 (char *)&keepidle, sizeof(keepidle));
2161                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2162                                 (char *)&keepidle, sizeof(keepidle));
2163                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2164                                 (char *)&keepcnt, sizeof(keepcnt));
2165
2166                 write_lock_bh(&sk->sk_callback_lock);
2167
2168                 xs_save_old_callbacks(transport, sk);
2169
2170                 sk->sk_user_data = xprt;
2171                 sk->sk_data_ready = xs_tcp_data_ready;
2172                 sk->sk_state_change = xs_tcp_state_change;
2173                 sk->sk_write_space = xs_tcp_write_space;
2174                 sk->sk_error_report = xs_error_report;
2175                 sk->sk_allocation = GFP_ATOMIC;
2176
2177                 /* socket options */
2178                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
2179                 sock_reset_flag(sk, SOCK_LINGER);
2180                 tcp_sk(sk)->linger2 = 0;
2181                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2182
2183                 xprt_clear_connected(xprt);
2184
2185                 /* Reset to new socket */
2186                 transport->sock = sock;
2187                 transport->inet = sk;
2188
2189                 write_unlock_bh(&sk->sk_callback_lock);
2190         }
2191
2192         if (!xprt_bound(xprt))
2193                 goto out;
2194
2195         xs_set_memalloc(xprt);
2196
2197         /* Tell the socket layer to start connecting... */
2198         xprt->stat.connect_count++;
2199         xprt->stat.connect_start = jiffies;
2200         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2201         switch (ret) {
2202         case 0:
2203         case -EINPROGRESS:
2204                 /* SYN_SENT! */
2205                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2206                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2207         }
2208 out:
2209         return ret;
2210 }
2211
2212 /**
2213  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2214  * @xprt: RPC transport to connect
2215  * @transport: socket transport to connect
2216  * @create_sock: function to create a socket of the correct type
2217  *
2218  * Invoked by a work queue tasklet.
2219  */
2220 static void xs_tcp_setup_socket(struct work_struct *work)
2221 {
2222         struct sock_xprt *transport =
2223                 container_of(work, struct sock_xprt, connect_worker.work);
2224         struct socket *sock = transport->sock;
2225         struct rpc_xprt *xprt = &transport->xprt;
2226         int status = -EIO;
2227
2228         current->flags |= PF_FSTRANS;
2229
2230         if (!sock) {
2231                 clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
2232                 sock = xs_create_sock(xprt, transport,
2233                                 xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
2234                 if (IS_ERR(sock)) {
2235                         status = PTR_ERR(sock);
2236                         goto out;
2237                 }
2238         } else {
2239                 int abort_and_exit;
2240
2241                 abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
2242                                 &xprt->state);
2243                 /* "close" the socket, preserving the local port */
2244                 xs_tcp_reuse_connection(transport);
2245
2246                 if (abort_and_exit)
2247                         goto out_eagain;
2248         }
2249
2250         dprintk("RPC:       worker connecting xprt %p via %s to "
2251                                 "%s (port %s)\n", xprt,
2252                         xprt->address_strings[RPC_DISPLAY_PROTO],
2253                         xprt->address_strings[RPC_DISPLAY_ADDR],
2254                         xprt->address_strings[RPC_DISPLAY_PORT]);
2255
2256         status = xs_tcp_finish_connecting(xprt, sock);
2257         trace_rpc_socket_connect(xprt, sock, status);
2258         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2259                         xprt, -status, xprt_connected(xprt),
2260                         sock->sk->sk_state);
2261         switch (status) {
2262         default:
2263                 printk("%s: connect returned unhandled error %d\n",
2264                         __func__, status);
2265         case -EADDRNOTAVAIL:
2266                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2267                  * and retry
2268                  */
2269                 xs_tcp_force_close(xprt);
2270                 break;
2271         case 0:
2272         case -EINPROGRESS:
2273         case -EALREADY:
2274                 xprt_clear_connecting(xprt);
2275                 current->flags &= ~PF_FSTRANS;
2276                 return;
2277         case -EINVAL:
2278                 /* Happens, for instance, if the user specified a link
2279                  * local IPv6 address without a scope-id.
2280                  */
2281         case -ECONNREFUSED:
2282         case -ECONNRESET:
2283         case -ENETUNREACH:
2284                 /* retry with existing socket, after a delay */
2285                 goto out;
2286         }
2287 out_eagain:
2288         status = -EAGAIN;
2289 out:
2290         xprt_clear_connecting(xprt);
2291         xprt_wake_pending_tasks(xprt, status);
2292         current->flags &= ~PF_FSTRANS;
2293 }
2294
2295 /**
2296  * xs_connect - connect a socket to a remote endpoint
2297  * @xprt: pointer to transport structure
2298  * @task: address of RPC task that manages state of connect request
2299  *
2300  * TCP: If the remote end dropped the connection, delay reconnecting.
2301  *
2302  * UDP socket connects are synchronous, but we use a work queue anyway
2303  * to guarantee that even unprivileged user processes can set up a
2304  * socket on a privileged port.
2305  *
2306  * If a UDP socket connect fails, the delay behavior here prevents
2307  * retry floods (hard mounts).
2308  */
2309 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2310 {
2311         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2312
2313         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
2314                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2315                                 "seconds\n",
2316                                 xprt, xprt->reestablish_timeout / HZ);
2317                 queue_delayed_work(rpciod_workqueue,
2318                                    &transport->connect_worker,
2319                                    xprt->reestablish_timeout);
2320                 xprt->reestablish_timeout <<= 1;
2321                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2322                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2323                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
2324                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
2325         } else {
2326                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2327                 queue_delayed_work(rpciod_workqueue,
2328                                    &transport->connect_worker, 0);
2329         }
2330 }
2331
2332 /**
2333  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2334  * @xprt: rpc_xprt struct containing statistics
2335  * @seq: output file
2336  *
2337  */
2338 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2339 {
2340         long idle_time = 0;
2341
2342         if (xprt_connected(xprt))
2343                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2344
2345         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2346                         "%llu %llu %lu %llu %llu\n",
2347                         xprt->stat.bind_count,
2348                         xprt->stat.connect_count,
2349                         xprt->stat.connect_time,
2350                         idle_time,
2351                         xprt->stat.sends,
2352                         xprt->stat.recvs,
2353                         xprt->stat.bad_xids,
2354                         xprt->stat.req_u,
2355                         xprt->stat.bklog_u,
2356                         xprt->stat.max_slots,
2357                         xprt->stat.sending_u,
2358                         xprt->stat.pending_u);
2359 }
2360
2361 /**
2362  * xs_udp_print_stats - display UDP socket-specifc stats
2363  * @xprt: rpc_xprt struct containing statistics
2364  * @seq: output file
2365  *
2366  */
2367 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2368 {
2369         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2370
2371         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2372                         "%lu %llu %llu\n",
2373                         transport->srcport,
2374                         xprt->stat.bind_count,
2375                         xprt->stat.sends,
2376                         xprt->stat.recvs,
2377                         xprt->stat.bad_xids,
2378                         xprt->stat.req_u,
2379                         xprt->stat.bklog_u,
2380                         xprt->stat.max_slots,
2381                         xprt->stat.sending_u,
2382                         xprt->stat.pending_u);
2383 }
2384
2385 /**
2386  * xs_tcp_print_stats - display TCP socket-specifc stats
2387  * @xprt: rpc_xprt struct containing statistics
2388  * @seq: output file
2389  *
2390  */
2391 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2392 {
2393         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2394         long idle_time = 0;
2395
2396         if (xprt_connected(xprt))
2397                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2398
2399         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2400                         "%llu %llu %lu %llu %llu\n",
2401                         transport->srcport,
2402                         xprt->stat.bind_count,
2403                         xprt->stat.connect_count,
2404                         xprt->stat.connect_time,
2405                         idle_time,
2406                         xprt->stat.sends,
2407                         xprt->stat.recvs,
2408                         xprt->stat.bad_xids,
2409                         xprt->stat.req_u,
2410                         xprt->stat.bklog_u,
2411                         xprt->stat.max_slots,
2412                         xprt->stat.sending_u,
2413                         xprt->stat.pending_u);
2414 }
2415
2416 /*
2417  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2418  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2419  * to use the server side send routines.
2420  */
2421 static void *bc_malloc(struct rpc_task *task, size_t size)
2422 {
2423         struct page *page;
2424         struct rpc_buffer *buf;
2425
2426         WARN_ON_ONCE(size > PAGE_SIZE - sizeof(struct rpc_buffer));
2427         if (size > PAGE_SIZE - sizeof(struct rpc_buffer))
2428                 return NULL;
2429
2430         page = alloc_page(GFP_KERNEL);
2431         if (!page)
2432                 return NULL;
2433
2434         buf = page_address(page);
2435         buf->len = PAGE_SIZE;
2436
2437         return buf->data;
2438 }
2439
2440 /*
2441  * Free the space allocated in the bc_alloc routine
2442  */
2443 static void bc_free(void *buffer)
2444 {
2445         struct rpc_buffer *buf;
2446
2447         if (!buffer)
2448                 return;
2449
2450         buf = container_of(buffer, struct rpc_buffer, data);
2451         free_page((unsigned long)buf);
2452 }
2453
2454 /*
2455  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2456  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2457  */
2458 static int bc_sendto(struct rpc_rqst *req)
2459 {
2460         int len;
2461         struct xdr_buf *xbufp = &req->rq_snd_buf;
2462         struct rpc_xprt *xprt = req->rq_xprt;
2463         struct sock_xprt *transport =
2464                                 container_of(xprt, struct sock_xprt, xprt);
2465         struct socket *sock = transport->sock;
2466         unsigned long headoff;
2467         unsigned long tailoff;
2468
2469         xs_encode_stream_record_marker(xbufp);
2470
2471         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2472         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2473         len = svc_send_common(sock, xbufp,
2474                               virt_to_page(xbufp->head[0].iov_base), headoff,
2475                               xbufp->tail[0].iov_base, tailoff);
2476
2477         if (len != xbufp->len) {
2478                 printk(KERN_NOTICE "Error sending entire callback!\n");
2479                 len = -EAGAIN;
2480         }
2481
2482         return len;
2483 }
2484
2485 /*
2486  * The send routine. Borrows from svc_send
2487  */
2488 static int bc_send_request(struct rpc_task *task)
2489 {
2490         struct rpc_rqst *req = task->tk_rqstp;
2491         struct svc_xprt *xprt;
2492         u32                     len;
2493
2494         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2495         /*
2496          * Get the server socket associated with this callback xprt
2497          */
2498         xprt = req->rq_xprt->bc_xprt;
2499
2500         /*
2501          * Grab the mutex to serialize data as the connection is shared
2502          * with the fore channel
2503          */
2504         if (!mutex_trylock(&xprt->xpt_mutex)) {
2505                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2506                 if (!mutex_trylock(&xprt->xpt_mutex))
2507                         return -EAGAIN;
2508                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2509         }
2510         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2511                 len = -ENOTCONN;
2512         else
2513                 len = bc_sendto(req);
2514         mutex_unlock(&xprt->xpt_mutex);
2515
2516         if (len > 0)
2517                 len = 0;
2518
2519         return len;
2520 }
2521
2522 /*
2523  * The close routine. Since this is client initiated, we do nothing
2524  */
2525
2526 static void bc_close(struct rpc_xprt *xprt)
2527 {
2528 }
2529
2530 /*
2531  * The xprt destroy routine. Again, because this connection is client
2532  * initiated, we do nothing
2533  */
2534
2535 static void bc_destroy(struct rpc_xprt *xprt)
2536 {
2537         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2538
2539         xs_xprt_free(xprt);
2540         module_put(THIS_MODULE);
2541 }
2542
2543 static struct rpc_xprt_ops xs_local_ops = {
2544         .reserve_xprt           = xprt_reserve_xprt,
2545         .release_xprt           = xs_tcp_release_xprt,
2546         .alloc_slot             = xprt_alloc_slot,
2547         .rpcbind                = xs_local_rpcbind,
2548         .set_port               = xs_local_set_port,
2549         .connect                = xs_local_connect,
2550         .buf_alloc              = rpc_malloc,
2551         .buf_free               = rpc_free,
2552         .send_request           = xs_local_send_request,
2553         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2554         .close                  = xs_close,
2555         .destroy                = xs_destroy,
2556         .print_stats            = xs_local_print_stats,
2557 };
2558
2559 static struct rpc_xprt_ops xs_udp_ops = {
2560         .set_buffer_size        = xs_udp_set_buffer_size,
2561         .reserve_xprt           = xprt_reserve_xprt_cong,
2562         .release_xprt           = xprt_release_xprt_cong,
2563         .alloc_slot             = xprt_alloc_slot,
2564         .rpcbind                = rpcb_getport_async,
2565         .set_port               = xs_set_port,
2566         .connect                = xs_connect,
2567         .buf_alloc              = rpc_malloc,
2568         .buf_free               = rpc_free,
2569         .send_request           = xs_udp_send_request,
2570         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2571         .timer                  = xs_udp_timer,
2572         .release_request        = xprt_release_rqst_cong,
2573         .close                  = xs_close,
2574         .destroy                = xs_destroy,
2575         .print_stats            = xs_udp_print_stats,
2576 };
2577
2578 static struct rpc_xprt_ops xs_tcp_ops = {
2579         .reserve_xprt           = xprt_reserve_xprt,
2580         .release_xprt           = xs_tcp_release_xprt,
2581         .alloc_slot             = xprt_lock_and_alloc_slot,
2582         .rpcbind                = rpcb_getport_async,
2583         .set_port               = xs_set_port,
2584         .connect                = xs_connect,
2585         .buf_alloc              = rpc_malloc,
2586         .buf_free               = rpc_free,
2587         .send_request           = xs_tcp_send_request,
2588         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2589         .close                  = xs_tcp_close,
2590         .destroy                = xs_destroy,
2591         .print_stats            = xs_tcp_print_stats,
2592 };
2593
2594 /*
2595  * The rpc_xprt_ops for the server backchannel
2596  */
2597
2598 static struct rpc_xprt_ops bc_tcp_ops = {
2599         .reserve_xprt           = xprt_reserve_xprt,
2600         .release_xprt           = xprt_release_xprt,
2601         .alloc_slot             = xprt_alloc_slot,
2602         .buf_alloc              = bc_malloc,
2603         .buf_free               = bc_free,
2604         .send_request           = bc_send_request,
2605         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2606         .close                  = bc_close,
2607         .destroy                = bc_destroy,
2608         .print_stats            = xs_tcp_print_stats,
2609 };
2610
2611 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2612 {
2613         static const struct sockaddr_in sin = {
2614                 .sin_family             = AF_INET,
2615                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2616         };
2617         static const struct sockaddr_in6 sin6 = {
2618                 .sin6_family            = AF_INET6,
2619                 .sin6_addr              = IN6ADDR_ANY_INIT,
2620         };
2621
2622         switch (family) {
2623         case AF_LOCAL:
2624                 break;
2625         case AF_INET:
2626                 memcpy(sap, &sin, sizeof(sin));
2627                 break;
2628         case AF_INET6:
2629                 memcpy(sap, &sin6, sizeof(sin6));
2630                 break;
2631         default:
2632                 dprintk("RPC:       %s: Bad address family\n", __func__);
2633                 return -EAFNOSUPPORT;
2634         }
2635         return 0;
2636 }
2637
2638 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2639                                       unsigned int slot_table_size,
2640                                       unsigned int max_slot_table_size)
2641 {
2642         struct rpc_xprt *xprt;
2643         struct sock_xprt *new;
2644
2645         if (args->addrlen > sizeof(xprt->addr)) {
2646                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2647                 return ERR_PTR(-EBADF);
2648         }
2649
2650         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2651                         max_slot_table_size);
2652         if (xprt == NULL) {
2653                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2654                                 "rpc_xprt\n");
2655                 return ERR_PTR(-ENOMEM);
2656         }
2657
2658         new = container_of(xprt, struct sock_xprt, xprt);
2659         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2660         xprt->addrlen = args->addrlen;
2661         if (args->srcaddr)
2662                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2663         else {
2664                 int err;
2665                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2666                                         (struct sockaddr *)&new->srcaddr);
2667                 if (err != 0) {
2668                         xprt_free(xprt);
2669                         return ERR_PTR(err);
2670                 }
2671         }
2672
2673         return xprt;
2674 }
2675
2676 static const struct rpc_timeout xs_local_default_timeout = {
2677         .to_initval = 10 * HZ,
2678         .to_maxval = 10 * HZ,
2679         .to_retries = 2,
2680 };
2681
2682 /**
2683  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2684  * @args: rpc transport creation arguments
2685  *
2686  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2687  */
2688 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2689 {
2690         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2691         struct sock_xprt *transport;
2692         struct rpc_xprt *xprt;
2693         struct rpc_xprt *ret;
2694
2695         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2696                         xprt_max_tcp_slot_table_entries);
2697         if (IS_ERR(xprt))
2698                 return xprt;
2699         transport = container_of(xprt, struct sock_xprt, xprt);
2700
2701         xprt->prot = 0;
2702         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2703         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2704
2705         xprt->bind_timeout = XS_BIND_TO;
2706         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2707         xprt->idle_timeout = XS_IDLE_DISC_TO;
2708
2709         xprt->ops = &xs_local_ops;
2710         xprt->timeout = &xs_local_default_timeout;
2711
2712         INIT_DELAYED_WORK(&transport->connect_worker,
2713                         xs_dummy_setup_socket);
2714
2715         switch (sun->sun_family) {
2716         case AF_LOCAL:
2717                 if (sun->sun_path[0] != '/') {
2718                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2719                                         sun->sun_path);
2720                         ret = ERR_PTR(-EINVAL);
2721                         goto out_err;
2722                 }
2723                 xprt_set_bound(xprt);
2724                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2725                 ret = ERR_PTR(xs_local_setup_socket(transport));
2726                 if (ret)
2727                         goto out_err;
2728                 break;
2729         default:
2730                 ret = ERR_PTR(-EAFNOSUPPORT);
2731                 goto out_err;
2732         }
2733
2734         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2735                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2736
2737         if (try_module_get(THIS_MODULE))
2738                 return xprt;
2739         ret = ERR_PTR(-EINVAL);
2740 out_err:
2741         xs_xprt_free(xprt);
2742         return ret;
2743 }
2744
2745 static const struct rpc_timeout xs_udp_default_timeout = {
2746         .to_initval = 5 * HZ,
2747         .to_maxval = 30 * HZ,
2748         .to_increment = 5 * HZ,
2749         .to_retries = 5,
2750 };
2751
2752 /**
2753  * xs_setup_udp - Set up transport to use a UDP socket
2754  * @args: rpc transport creation arguments
2755  *
2756  */
2757 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2758 {
2759         struct sockaddr *addr = args->dstaddr;
2760         struct rpc_xprt *xprt;
2761         struct sock_xprt *transport;
2762         struct rpc_xprt *ret;
2763
2764         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2765                         xprt_udp_slot_table_entries);
2766         if (IS_ERR(xprt))
2767                 return xprt;
2768         transport = container_of(xprt, struct sock_xprt, xprt);
2769
2770         xprt->prot = IPPROTO_UDP;
2771         xprt->tsh_size = 0;
2772         /* XXX: header size can vary due to auth type, IPv6, etc. */
2773         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2774
2775         xprt->bind_timeout = XS_BIND_TO;
2776         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2777         xprt->idle_timeout = XS_IDLE_DISC_TO;
2778
2779         xprt->ops = &xs_udp_ops;
2780
2781         xprt->timeout = &xs_udp_default_timeout;
2782
2783         switch (addr->sa_family) {
2784         case AF_INET:
2785                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2786                         xprt_set_bound(xprt);
2787
2788                 INIT_DELAYED_WORK(&transport->connect_worker,
2789                                         xs_udp_setup_socket);
2790                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2791                 break;
2792         case AF_INET6:
2793                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2794                         xprt_set_bound(xprt);
2795
2796                 INIT_DELAYED_WORK(&transport->connect_worker,
2797                                         xs_udp_setup_socket);
2798                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2799                 break;
2800         default:
2801                 ret = ERR_PTR(-EAFNOSUPPORT);
2802                 goto out_err;
2803         }
2804
2805         if (xprt_bound(xprt))
2806                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2807                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2808                                 xprt->address_strings[RPC_DISPLAY_PORT],
2809                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2810         else
2811                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2812                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2813                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2814
2815         if (try_module_get(THIS_MODULE))
2816                 return xprt;
2817         ret = ERR_PTR(-EINVAL);
2818 out_err:
2819         xs_xprt_free(xprt);
2820         return ret;
2821 }
2822
2823 static const struct rpc_timeout xs_tcp_default_timeout = {
2824         .to_initval = 60 * HZ,
2825         .to_maxval = 60 * HZ,
2826         .to_retries = 2,
2827 };
2828
2829 /**
2830  * xs_setup_tcp - Set up transport to use a TCP socket
2831  * @args: rpc transport creation arguments
2832  *
2833  */
2834 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2835 {
2836         struct sockaddr *addr = args->dstaddr;
2837         struct rpc_xprt *xprt;
2838         struct sock_xprt *transport;
2839         struct rpc_xprt *ret;
2840         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2841
2842         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2843                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2844
2845         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2846                         max_slot_table_size);
2847         if (IS_ERR(xprt))
2848                 return xprt;
2849         transport = container_of(xprt, struct sock_xprt, xprt);
2850
2851         xprt->prot = IPPROTO_TCP;
2852         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2853         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2854
2855         xprt->bind_timeout = XS_BIND_TO;
2856         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2857         xprt->idle_timeout = XS_IDLE_DISC_TO;
2858
2859         xprt->ops = &xs_tcp_ops;
2860         xprt->timeout = &xs_tcp_default_timeout;
2861
2862         switch (addr->sa_family) {
2863         case AF_INET:
2864                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2865                         xprt_set_bound(xprt);
2866
2867                 INIT_DELAYED_WORK(&transport->connect_worker,
2868                                         xs_tcp_setup_socket);
2869                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2870                 break;
2871         case AF_INET6:
2872                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2873                         xprt_set_bound(xprt);
2874
2875                 INIT_DELAYED_WORK(&transport->connect_worker,
2876                                         xs_tcp_setup_socket);
2877                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2878                 break;
2879         default:
2880                 ret = ERR_PTR(-EAFNOSUPPORT);
2881                 goto out_err;
2882         }
2883
2884         if (xprt_bound(xprt))
2885                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2886                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2887                                 xprt->address_strings[RPC_DISPLAY_PORT],
2888                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2889         else
2890                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2891                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2892                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2893
2894         if (try_module_get(THIS_MODULE))
2895                 return xprt;
2896         ret = ERR_PTR(-EINVAL);
2897 out_err:
2898         xs_xprt_free(xprt);
2899         return ret;
2900 }
2901
2902 /**
2903  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2904  * @args: rpc transport creation arguments
2905  *
2906  */
2907 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2908 {
2909         struct sockaddr *addr = args->dstaddr;
2910         struct rpc_xprt *xprt;
2911         struct sock_xprt *transport;
2912         struct svc_sock *bc_sock;
2913         struct rpc_xprt *ret;
2914
2915         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2916                         xprt_tcp_slot_table_entries);
2917         if (IS_ERR(xprt))
2918                 return xprt;
2919         transport = container_of(xprt, struct sock_xprt, xprt);
2920
2921         xprt->prot = IPPROTO_TCP;
2922         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2923         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2924         xprt->timeout = &xs_tcp_default_timeout;
2925
2926         /* backchannel */
2927         xprt_set_bound(xprt);
2928         xprt->bind_timeout = 0;
2929         xprt->reestablish_timeout = 0;
2930         xprt->idle_timeout = 0;
2931
2932         xprt->ops = &bc_tcp_ops;
2933
2934         switch (addr->sa_family) {
2935         case AF_INET:
2936                 xs_format_peer_addresses(xprt, "tcp",
2937                                          RPCBIND_NETID_TCP);
2938                 break;
2939         case AF_INET6:
2940                 xs_format_peer_addresses(xprt, "tcp",
2941                                    RPCBIND_NETID_TCP6);
2942                 break;
2943         default:
2944                 ret = ERR_PTR(-EAFNOSUPPORT);
2945                 goto out_err;
2946         }
2947
2948         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2949                         xprt->address_strings[RPC_DISPLAY_ADDR],
2950                         xprt->address_strings[RPC_DISPLAY_PORT],
2951                         xprt->address_strings[RPC_DISPLAY_PROTO]);
2952
2953         /*
2954          * Once we've associated a backchannel xprt with a connection,
2955          * we want to keep it around as long as the connection lasts,
2956          * in case we need to start using it for a backchannel again;
2957          * this reference won't be dropped until bc_xprt is destroyed.
2958          */
2959         xprt_get(xprt);
2960         args->bc_xprt->xpt_bc_xprt = xprt;
2961         xprt->bc_xprt = args->bc_xprt;
2962         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2963         transport->sock = bc_sock->sk_sock;
2964         transport->inet = bc_sock->sk_sk;
2965
2966         /*
2967          * Since we don't want connections for the backchannel, we set
2968          * the xprt status to connected
2969          */
2970         xprt_set_connected(xprt);
2971
2972         if (try_module_get(THIS_MODULE))
2973                 return xprt;
2974
2975         args->bc_xprt->xpt_bc_xprt = NULL;
2976         xprt_put(xprt);
2977         ret = ERR_PTR(-EINVAL);
2978 out_err:
2979         xs_xprt_free(xprt);
2980         return ret;
2981 }
2982
2983 static struct xprt_class        xs_local_transport = {
2984         .list           = LIST_HEAD_INIT(xs_local_transport.list),
2985         .name           = "named UNIX socket",
2986         .owner          = THIS_MODULE,
2987         .ident          = XPRT_TRANSPORT_LOCAL,
2988         .setup          = xs_setup_local,
2989 };
2990
2991 static struct xprt_class        xs_udp_transport = {
2992         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2993         .name           = "udp",
2994         .owner          = THIS_MODULE,
2995         .ident          = XPRT_TRANSPORT_UDP,
2996         .setup          = xs_setup_udp,
2997 };
2998
2999 static struct xprt_class        xs_tcp_transport = {
3000         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3001         .name           = "tcp",
3002         .owner          = THIS_MODULE,
3003         .ident          = XPRT_TRANSPORT_TCP,
3004         .setup          = xs_setup_tcp,
3005 };
3006
3007 static struct xprt_class        xs_bc_tcp_transport = {
3008         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3009         .name           = "tcp NFSv4.1 backchannel",
3010         .owner          = THIS_MODULE,
3011         .ident          = XPRT_TRANSPORT_BC_TCP,
3012         .setup          = xs_setup_bc_tcp,
3013 };
3014
3015 /**
3016  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3017  *
3018  */
3019 int init_socket_xprt(void)
3020 {
3021 #ifdef RPC_DEBUG
3022         if (!sunrpc_table_header)
3023                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3024 #endif
3025
3026         xprt_register_transport(&xs_local_transport);
3027         xprt_register_transport(&xs_udp_transport);
3028         xprt_register_transport(&xs_tcp_transport);
3029         xprt_register_transport(&xs_bc_tcp_transport);
3030
3031         return 0;
3032 }
3033
3034 /**
3035  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3036  *
3037  */
3038 void cleanup_socket_xprt(void)
3039 {
3040 #ifdef RPC_DEBUG
3041         if (sunrpc_table_header) {
3042                 unregister_sysctl_table(sunrpc_table_header);
3043                 sunrpc_table_header = NULL;
3044         }
3045 #endif
3046
3047         xprt_unregister_transport(&xs_local_transport);
3048         xprt_unregister_transport(&xs_udp_transport);
3049         xprt_unregister_transport(&xs_tcp_transport);
3050         xprt_unregister_transport(&xs_bc_tcp_transport);
3051 }
3052
3053 static int param_set_uint_minmax(const char *val,
3054                 const struct kernel_param *kp,
3055                 unsigned int min, unsigned int max)
3056 {
3057         unsigned long num;
3058         int ret;
3059
3060         if (!val)
3061                 return -EINVAL;
3062         ret = strict_strtoul(val, 0, &num);
3063         if (ret == -EINVAL || num < min || num > max)
3064                 return -EINVAL;
3065         *((unsigned int *)kp->arg) = num;
3066         return 0;
3067 }
3068
3069 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3070 {
3071         return param_set_uint_minmax(val, kp,
3072                         RPC_MIN_RESVPORT,
3073                         RPC_MAX_RESVPORT);
3074 }
3075
3076 static struct kernel_param_ops param_ops_portnr = {
3077         .set = param_set_portnr,
3078         .get = param_get_uint,
3079 };
3080
3081 #define param_check_portnr(name, p) \
3082         __param_check(name, p, unsigned int);
3083
3084 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3085 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3086
3087 static int param_set_slot_table_size(const char *val,
3088                                      const struct kernel_param *kp)
3089 {
3090         return param_set_uint_minmax(val, kp,
3091                         RPC_MIN_SLOT_TABLE,
3092                         RPC_MAX_SLOT_TABLE);
3093 }
3094
3095 static struct kernel_param_ops param_ops_slot_table_size = {
3096         .set = param_set_slot_table_size,
3097         .get = param_get_uint,
3098 };
3099
3100 #define param_check_slot_table_size(name, p) \
3101         __param_check(name, p, unsigned int);
3102
3103 static int param_set_max_slot_table_size(const char *val,
3104                                      const struct kernel_param *kp)
3105 {
3106         return param_set_uint_minmax(val, kp,
3107                         RPC_MIN_SLOT_TABLE,
3108                         RPC_MAX_SLOT_TABLE_LIMIT);
3109 }
3110
3111 static struct kernel_param_ops param_ops_max_slot_table_size = {
3112         .set = param_set_max_slot_table_size,
3113         .get = param_get_uint,
3114 };
3115
3116 #define param_check_max_slot_table_size(name, p) \
3117         __param_check(name, p, unsigned int);
3118
3119 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3120                    slot_table_size, 0644);
3121 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3122                    max_slot_table_size, 0644);
3123 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3124                    slot_table_size, 0644);
3125