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, int *sent_p)
 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;
 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_p += err;
 428                 ppage++;
 429                 base = 0;
 430         }
 431         if (err > 0) {
 432                 *sent_p += err;
 433                 err = 0;
 434         }
 435         return err;
 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  * @sent_p: return the total number of bytes successfully queued for sending
 447  *
 448  */
 449 static int xs_sendpages(struct socket *sock, struct sockaddr *addr, int addrlen, struct xdr_buf *xdr, unsigned int base, bool zerocopy, int *sent_p)
 450 {
 451         unsigned int remainder = xdr->len - base;
 452         int err = 0;
 453         int sent = 0;
 454
 455         if (unlikely(!sock))
 456                 return -ENOTSOCK;
 457
 458         clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
 459         if (base != 0) {
 460                 addr = NULL;
 461                 addrlen = 0;
 462         }
 463
 464         if (base < xdr->head[0].iov_len || addr != NULL) {
 465                 unsigned int len = xdr->head[0].iov_len - base;
 466                 remainder -= len;
 467                 err = xs_send_kvec(sock, addr, addrlen, &xdr->head[0], base, remainder != 0);
 468                 if (remainder == 0 || err != len)
 469                         goto out;
 470                 *sent_p += err;
 471                 base = 0;
 472         } else
 473                 base -= xdr->head[0].iov_len;
 474
 475         if (base < xdr->page_len) {
 476                 unsigned int len = xdr->page_len - base;
 477                 remainder -= len;
 478                 err = xs_send_pagedata(sock, xdr, base, remainder != 0, zerocopy, &sent);
 479                 *sent_p += sent;
 480                 if (remainder == 0 || sent != len)
 481                         goto out;
 482                 base = 0;
 483         } else
 484                 base -= xdr->page_len;
 485
 486         if (base >= xdr->tail[0].iov_len)
 487                 return 0;
 488         err = xs_send_kvec(sock, NULL, 0, &xdr->tail[0], base, 0);
 489 out:
 490         if (err > 0) {
 491                 *sent_p += err;
 492                 err = 0;
 493         }
 494         return err;
 495 }
 496
 497 static void xs_nospace_callback(struct rpc_task *task)
 498 {
 499         struct sock_xprt *transport = container_of(task->tk_rqstp->rq_xprt, struct sock_xprt, xprt);
 500
 501         transport->inet->sk_write_pending--;
 502         clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 503 }
 504
 505 /**
 506  * xs_nospace - place task on wait queue if transmit was incomplete
 507  * @task: task to put to sleep
 508  *
 509  */
 510 static int xs_nospace(struct rpc_task *task)
 511 {
 512         struct rpc_rqst *req = task->tk_rqstp;
 513         struct rpc_xprt *xprt = req->rq_xprt;
 514         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 515         struct sock *sk = transport->inet;
 516         int ret = -EAGAIN;
 517
 518         dprintk("RPC: %5u xmit incomplete (%u left of %u)\n",
 519                         task->tk_pid, req->rq_slen - req->rq_bytes_sent,
 520                         req->rq_slen);
 521
 522         /* Protect against races with write_space */
 523         spin_lock_bh(&xprt->transport_lock);
 524
 525         /* Don't race with disconnect */
 526         if (xprt_connected(xprt)) {
 527                 if (test_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags)) {
 528                         /*
 529                          * Notify TCP that we're limited by the application
 530                          * window size
 531                          */
 532                         set_bit(SOCK_NOSPACE, &transport->sock->flags);
 533                         sk->sk_write_pending++;
 534                         /* ...and wait for more buffer space */
 535                         xprt_wait_for_buffer_space(task, xs_nospace_callback);
 536                 }
 537         } else {
 538                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 539                 ret = -ENOTCONN;
 540         }
 541
 542         spin_unlock_bh(&xprt->transport_lock);
 543
 544         /* Race breaker in case memory is freed before above code is called */
 545         sk->sk_write_space(sk);
 546         return ret;
 547 }
 548
 549 /*
 550  * Construct a stream transport record marker in @buf.
 551  */
 552 static inline void xs_encode_stream_record_marker(struct xdr_buf *buf)
 553 {
 554         u32 reclen = buf->len - sizeof(rpc_fraghdr);
 555         rpc_fraghdr *base = buf->head[0].iov_base;
 556         *base = cpu_to_be32(RPC_LAST_STREAM_FRAGMENT | reclen);
 557 }
 558
 559 /**
 560  * xs_local_send_request - write an RPC request to an AF_LOCAL socket
 561  * @task: RPC task that manages the state of an RPC request
 562  *
 563  * Return values:
 564  *        0:    The request has been sent
 565  *   EAGAIN:    The socket was blocked, please call again later to
 566  *              complete the request
 567  * ENOTCONN:    Caller needs to invoke connect logic then call again
 568  *    other:    Some other error occured, the request was not sent
 569  */
 570 static int xs_local_send_request(struct rpc_task *task)
 571 {
 572         struct rpc_rqst *req = task->tk_rqstp;
 573         struct rpc_xprt *xprt = req->rq_xprt;
 574         struct sock_xprt *transport =
 575                                 container_of(xprt, struct sock_xprt, xprt);
 576         struct xdr_buf *xdr = &req->rq_snd_buf;
 577         int status;
 578         int sent = 0;
 579
 580         xs_encode_stream_record_marker(&req->rq_snd_buf);
 581
 582         xs_pktdump("packet data:",
 583                         req->rq_svec->iov_base, req->rq_svec->iov_len);
 584
 585         status = xs_sendpages(transport->sock, NULL, 0, xdr, req->rq_bytes_sent,
 586                               true, &sent);
 587         dprintk("RPC:       %s(%u) = %d\n",
 588                         __func__, xdr->len - req->rq_bytes_sent, status);
 589         if (likely(sent > 0) || status == 0) {
 590                 req->rq_bytes_sent += sent;
 591                 req->rq_xmit_bytes_sent += sent;
 592                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 593                         req->rq_bytes_sent = 0;
 594                         return 0;
 595                 }
 596                 status = -EAGAIN;
 597         }
 598
 599         switch (status) {
 600         case -ENOBUFS:
 601         case -EAGAIN:
 602                 status = xs_nospace(task);
 603                 break;
 604         default:
 605                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 606                         -status);
 607         case -EPIPE:
 608                 xs_close(xprt);
 609                 status = -ENOTCONN;
 610         }
 611
 612         return status;
 613 }
 614
 615 /**
 616  * xs_udp_send_request - write an RPC request to a UDP socket
 617  * @task: address of RPC task that manages the state of an RPC request
 618  *
 619  * Return values:
 620  *        0:    The request has been sent
 621  *   EAGAIN:    The socket was blocked, please call again later to
 622  *              complete the request
 623  * ENOTCONN:    Caller needs to invoke connect logic then call again
 624  *    other:    Some other error occurred, the request was not sent
 625  */
 626 static int xs_udp_send_request(struct rpc_task *task)
 627 {
 628         struct rpc_rqst *req = task->tk_rqstp;
 629         struct rpc_xprt *xprt = req->rq_xprt;
 630         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 631         struct xdr_buf *xdr = &req->rq_snd_buf;
 632         int sent = 0;
 633         int status;
 634
 635         xs_pktdump("packet data:",
 636                                 req->rq_svec->iov_base,
 637                                 req->rq_svec->iov_len);
 638
 639         if (!xprt_bound(xprt))
 640                 return -ENOTCONN;
 641         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 642                               xdr, req->rq_bytes_sent, true, &sent);
 643
 644         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 645                         xdr->len - req->rq_bytes_sent, status);
 646
 647         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 648         if (status == -EPERM)
 649                 goto process_status;
 650
 651         if (sent > 0 || status == 0) {
 652                 req->rq_xmit_bytes_sent += sent;
 653                 if (sent >= req->rq_slen)
 654                         return 0;
 655                 /* Still some bytes left; set up for a retry later. */
 656                 status = -EAGAIN;
 657         }
 658
 659 process_status:
 660         switch (status) {
 661         case -ENOTSOCK:
 662                 status = -ENOTCONN;
 663                 /* Should we call xs_close() here? */
 664                 break;
 665         case -EAGAIN:
 666                 status = xs_nospace(task);
 667                 break;
 668         default:
 669                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 670                         -status);
 671         case -ENETUNREACH:
 672         case -ENOBUFS:
 673         case -EPIPE:
 674         case -ECONNREFUSED:
 675         case -EPERM:
 676                 /* When the server has died, an ICMP port unreachable message
 677                  * prompts ECONNREFUSED. */
 678                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 679         }
 680
 681         return status;
 682 }
 683
 684 /**
 685  * xs_tcp_shutdown - gracefully shut down a TCP socket
 686  * @xprt: transport
 687  *
 688  * Initiates a graceful shutdown of the TCP socket by calling the
 689  * equivalent of shutdown(SHUT_WR);
 690  */
 691 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
 692 {
 693         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 694         struct socket *sock = transport->sock;
 695
 696         if (sock != NULL) {
 697                 kernel_sock_shutdown(sock, SHUT_WR);
 698                 trace_rpc_socket_shutdown(xprt, sock);
 699         }
 700 }
 701
 702 /**
 703  * xs_tcp_send_request - write an RPC request to a TCP socket
 704  * @task: address of RPC task that manages the state of an RPC request
 705  *
 706  * Return values:
 707  *        0:    The request has been sent
 708  *   EAGAIN:    The socket was blocked, please call again later to
 709  *              complete the request
 710  * ENOTCONN:    Caller needs to invoke connect logic then call again
 711  *    other:    Some other error occurred, the request was not sent
 712  *
 713  * XXX: In the case of soft timeouts, should we eventually give up
 714  *      if sendmsg is not able to make progress?
 715  */
 716 static int xs_tcp_send_request(struct rpc_task *task)
 717 {
 718         struct rpc_rqst *req = task->tk_rqstp;
 719         struct rpc_xprt *xprt = req->rq_xprt;
 720         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 721         struct xdr_buf *xdr = &req->rq_snd_buf;
 722         bool zerocopy = true;
 723         int status;
 724         int sent;
 725
 726         xs_encode_stream_record_marker(&req->rq_snd_buf);
 727
 728         xs_pktdump("packet data:",
 729                                 req->rq_svec->iov_base,
 730                                 req->rq_svec->iov_len);
 731         /* Don't use zero copy if this is a resend. If the RPC call
 732          * completes while the socket holds a reference to the pages,
 733          * then we may end up resending corrupted data.
 734          */
 735         if (task->tk_flags & RPC_TASK_SENT)
 736                 zerocopy = false;
 737
 738         /* Continue transmitting the packet/record. We must be careful
 739          * to cope with writespace callbacks arriving _after_ we have
 740          * called sendmsg(). */
 741         while (1) {
 742                 sent = 0;
 743                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
 744                                       req->rq_bytes_sent, zerocopy, &sent);
 745
 746                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 747                                 xdr->len - req->rq_bytes_sent, status);
 748
 749                 if (unlikely(sent == 0 && status < 0))
 750                         break;
 751
 752                 /* If we've sent the entire packet, immediately
 753                  * reset the count of bytes sent. */
 754                 req->rq_bytes_sent += sent;
 755                 req->rq_xmit_bytes_sent += sent;
 756                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 757                         req->rq_bytes_sent = 0;
 758                         return 0;
 759                 }
 760
 761                 if (sent != 0)
 762                         continue;
 763                 status = -EAGAIN;
 764                 break;
 765         }
 766
 767         switch (status) {
 768         case -ENOTSOCK:
 769                 status = -ENOTCONN;
 770                 /* Should we call xs_close() here? */
 771                 break;
 772         case -ENOBUFS:
 773         case -EAGAIN:
 774                 status = xs_nospace(task);
 775                 break;
 776         default:
 777                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 778                         -status);
 779         case -ECONNRESET:
 780                 xs_tcp_shutdown(xprt);
 781         case -ECONNREFUSED:
 782         case -ENOTCONN:
 783         case -EPIPE:
 784                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 785         }
 786
 787         return status;
 788 }
 789
 790 /**
 791  * xs_tcp_release_xprt - clean up after a tcp transmission
 792  * @xprt: transport
 793  * @task: rpc task
 794  *
 795  * This cleans up if an error causes us to abort the transmission of a request.
 796  * In this case, the socket may need to be reset in order to avoid confusing
 797  * the server.
 798  */
 799 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 800 {
 801         struct rpc_rqst *req;
 802
 803         if (task != xprt->snd_task)
 804                 return;
 805         if (task == NULL)
 806                 goto out_release;
 807         req = task->tk_rqstp;
 808         if (req == NULL)
 809                 goto out_release;
 810         if (req->rq_bytes_sent == 0)
 811                 goto out_release;
 812         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 813                 goto out_release;
 814         set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 815 out_release:
 816         xprt_release_xprt(xprt, task);
 817 }
 818
 819 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 820 {
 821         transport->old_data_ready = sk->sk_data_ready;
 822         transport->old_state_change = sk->sk_state_change;
 823         transport->old_write_space = sk->sk_write_space;
 824         transport->old_error_report = sk->sk_error_report;
 825 }
 826
 827 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 828 {
 829         sk->sk_data_ready = transport->old_data_ready;
 830         sk->sk_state_change = transport->old_state_change;
 831         sk->sk_write_space = transport->old_write_space;
 832         sk->sk_error_report = transport->old_error_report;
 833 }
 834
 835 /**
 836  * xs_error_report - callback to handle TCP socket state errors
 837  * @sk: socket
 838  *
 839  * Note: we don't call sock_error() since there may be a rpc_task
 840  * using the socket, and so we don't want to clear sk->sk_err.
 841  */
 842 static void xs_error_report(struct sock *sk)
 843 {
 844         struct rpc_xprt *xprt;
 845         int err;
 846
 847         read_lock_bh(&sk->sk_callback_lock);
 848         if (!(xprt = xprt_from_sock(sk)))
 849                 goto out;
 850
 851         err = -sk->sk_err;
 852         if (err == 0)
 853                 goto out;
 854         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
 855                         xprt, -err);
 856         trace_rpc_socket_error(xprt, sk->sk_socket, err);
 857         if (test_bit(XPRT_CONNECTION_REUSE, &xprt->state))
 858                 goto out;
 859         xprt_wake_pending_tasks(xprt, err);
 860  out:
 861         read_unlock_bh(&sk->sk_callback_lock);
 862 }
 863
 864 static void xs_reset_transport(struct sock_xprt *transport)
 865 {
 866         struct socket *sock = transport->sock;
 867         struct sock *sk = transport->inet;
 868
 869         if (sk == NULL)
 870                 return;
 871
 872         transport->srcport = 0;
 873
 874         write_lock_bh(&sk->sk_callback_lock);
 875         transport->inet = NULL;
 876         transport->sock = NULL;
 877
 878         sk->sk_user_data = NULL;
 879
 880         xs_restore_old_callbacks(transport, sk);
 881         write_unlock_bh(&sk->sk_callback_lock);
 882
 883         trace_rpc_socket_close(&transport->xprt, sock);
 884         sock_release(sock);
 885 }
 886
 887 /**
 888  * xs_close - close a socket
 889  * @xprt: transport
 890  *
 891  * This is used when all requests are complete; ie, no DRC state remains
 892  * on the server we want to save.
 893  *
 894  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 895  * xs_reset_transport() zeroing the socket from underneath a writer.
 896  */
 897 static void xs_close(struct rpc_xprt *xprt)
 898 {
 899         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 900
 901         dprintk("RPC:       xs_close xprt %p\n", xprt);
 902
 903         cancel_delayed_work_sync(&transport->connect_worker);
 904
 905         xs_reset_transport(transport);
 906         xprt->reestablish_timeout = 0;
 907
 908         smp_mb__before_atomic();
 909         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
 910         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 911         clear_bit(XPRT_CLOSING, &xprt->state);
 912         smp_mb__after_atomic();
 913         xprt_disconnect_done(xprt);
 914 }
 915
 916 static void xs_tcp_close(struct rpc_xprt *xprt)
 917 {
 918         if (test_and_clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state))
 919                 xs_close(xprt);
 920         else
 921                 xs_tcp_shutdown(xprt);
 922 }
 923
 924 static void xs_xprt_free(struct rpc_xprt *xprt)
 925 {
 926         xs_free_peer_addresses(xprt);
 927         xprt_free(xprt);
 928 }
 929
 930 /**
 931  * xs_destroy - prepare to shutdown a transport
 932  * @xprt: doomed transport
 933  *
 934  */
 935 static void xs_destroy(struct rpc_xprt *xprt)
 936 {
 937         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 938
 939         xs_close(xprt);
 940         xs_xprt_free(xprt);
 941         module_put(THIS_MODULE);
 942 }
 943
 944 static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 945 {
 946         struct xdr_skb_reader desc = {
 947                 .skb            = skb,
 948                 .offset         = sizeof(rpc_fraghdr),
 949                 .count          = skb->len - sizeof(rpc_fraghdr),
 950         };
 951
 952         if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
 953                 return -1;
 954         if (desc.count)
 955                 return -1;
 956         return 0;
 957 }
 958
 959 /**
 960  * xs_local_data_ready - "data ready" callback for AF_LOCAL sockets
 961  * @sk: socket with data to read
 962  * @len: how much data to read
 963  *
 964  * Currently this assumes we can read the whole reply in a single gulp.
 965  */
 966 static void xs_local_data_ready(struct sock *sk)
 967 {
 968         struct rpc_task *task;
 969         struct rpc_xprt *xprt;
 970         struct rpc_rqst *rovr;
 971         struct sk_buff *skb;
 972         int err, repsize, copied;
 973         u32 _xid;
 974         __be32 *xp;
 975
 976         read_lock_bh(&sk->sk_callback_lock);
 977         dprintk("RPC:       %s...\n", __func__);
 978         xprt = xprt_from_sock(sk);
 979         if (xprt == NULL)
 980                 goto out;
 981
 982         skb = skb_recv_datagram(sk, 0, 1, &err);
 983         if (skb == NULL)
 984                 goto out;
 985
 986         repsize = skb->len - sizeof(rpc_fraghdr);
 987         if (repsize < 4) {
 988                 dprintk("RPC:       impossible RPC reply size %d\n", repsize);
 989                 goto dropit;
 990         }
 991
 992         /* Copy the XID from the skb... */
 993         xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid);
 994         if (xp == NULL)
 995                 goto dropit;
 996
 997         /* Look up and lock the request corresponding to the given XID */
 998         spin_lock(&xprt->transport_lock);
 999         rovr = xprt_lookup_rqst(xprt, *xp);
1000         if (!rovr)
1001                 goto out_unlock;
1002         task = rovr->rq_task;
1003
1004         copied = rovr->rq_private_buf.buflen;
1005         if (copied > repsize)
1006                 copied = repsize;
1007
1008         if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1009                 dprintk("RPC:       sk_buff copy failed\n");
1010                 goto out_unlock;
1011         }
1012
1013         xprt_complete_rqst(task, copied);
1014
1015  out_unlock:
1016         spin_unlock(&xprt->transport_lock);
1017  dropit:
1018         skb_free_datagram(sk, skb);
1019  out:
1020         read_unlock_bh(&sk->sk_callback_lock);
1021 }
1022
1023 /**
1024  * xs_udp_data_ready - "data ready" callback for UDP sockets
1025  * @sk: socket with data to read
1026  * @len: how much data to read
1027  *
1028  */
1029 static void xs_udp_data_ready(struct sock *sk)
1030 {
1031         struct rpc_task *task;
1032         struct rpc_xprt *xprt;
1033         struct rpc_rqst *rovr;
1034         struct sk_buff *skb;
1035         int err, repsize, copied;
1036         u32 _xid;
1037         __be32 *xp;
1038
1039         read_lock_bh(&sk->sk_callback_lock);
1040         dprintk("RPC:       xs_udp_data_ready...\n");
1041         if (!(xprt = xprt_from_sock(sk)))
1042                 goto out;
1043
1044         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
1045                 goto out;
1046
1047         repsize = skb->len - sizeof(struct udphdr);
1048         if (repsize < 4) {
1049                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
1050                 goto dropit;
1051         }
1052
1053         /* Copy the XID from the skb... */
1054         xp = skb_header_pointer(skb, sizeof(struct udphdr),
1055                                 sizeof(_xid), &_xid);
1056         if (xp == NULL)
1057                 goto dropit;
1058
1059         /* Look up and lock the request corresponding to the given XID */
1060         spin_lock(&xprt->transport_lock);
1061         rovr = xprt_lookup_rqst(xprt, *xp);
1062         if (!rovr)
1063                 goto out_unlock;
1064         task = rovr->rq_task;
1065
1066         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1067                 copied = repsize;
1068
1069         /* Suck it into the iovec, verify checksum if not done by hw. */
1070         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1071                 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
1072                 goto out_unlock;
1073         }
1074
1075         UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
1076
1077         xprt_adjust_cwnd(xprt, task, copied);
1078         xprt_complete_rqst(task, copied);
1079
1080  out_unlock:
1081         spin_unlock(&xprt->transport_lock);
1082  dropit:
1083         skb_free_datagram(sk, skb);
1084  out:
1085         read_unlock_bh(&sk->sk_callback_lock);
1086 }
1087
1088 /*
1089  * Helper function to force a TCP close if the server is sending
1090  * junk and/or it has put us in CLOSE_WAIT
1091  */
1092 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1093 {
1094         set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1095         xprt_force_disconnect(xprt);
1096 }
1097
1098 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
1099 {
1100         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1101         size_t len, used;
1102         char *p;
1103
1104         p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
1105         len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
1106         used = xdr_skb_read_bits(desc, p, len);
1107         transport->tcp_offset += used;
1108         if (used != len)
1109                 return;
1110
1111         transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
1112         if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
1113                 transport->tcp_flags |= TCP_RCV_LAST_FRAG;
1114         else
1115                 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
1116         transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
1117
1118         transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
1119         transport->tcp_offset = 0;
1120
1121         /* Sanity check of the record length */
1122         if (unlikely(transport->tcp_reclen < 8)) {
1123                 dprintk("RPC:       invalid TCP record fragment length\n");
1124                 xs_tcp_force_close(xprt);
1125                 return;
1126         }
1127         dprintk("RPC:       reading TCP record fragment of length %d\n",
1128                         transport->tcp_reclen);
1129 }
1130
1131 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
1132 {
1133         if (transport->tcp_offset == transport->tcp_reclen) {
1134                 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
1135                 transport->tcp_offset = 0;
1136                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
1137                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1138                         transport->tcp_flags |= TCP_RCV_COPY_XID;
1139                         transport->tcp_copied = 0;
1140                 }
1141         }
1142 }
1143
1144 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1145 {
1146         size_t len, used;
1147         char *p;
1148
1149         len = sizeof(transport->tcp_xid) - transport->tcp_offset;
1150         dprintk("RPC:       reading XID (%Zu bytes)\n", len);
1151         p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
1152         used = xdr_skb_read_bits(desc, p, len);
1153         transport->tcp_offset += used;
1154         if (used != len)
1155                 return;
1156         transport->tcp_flags &= ~TCP_RCV_COPY_XID;
1157         transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
1158         transport->tcp_copied = 4;
1159         dprintk("RPC:       reading %s XID %08x\n",
1160                         (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
1161                                                               : "request with",
1162                         ntohl(transport->tcp_xid));
1163         xs_tcp_check_fraghdr(transport);
1164 }
1165
1166 static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
1167                                        struct xdr_skb_reader *desc)
1168 {
1169         size_t len, used;
1170         u32 offset;
1171         char *p;
1172
1173         /*
1174          * We want transport->tcp_offset to be 8 at the end of this routine
1175          * (4 bytes for the xid and 4 bytes for the call/reply flag).
1176          * When this function is called for the first time,
1177          * transport->tcp_offset is 4 (after having already read the xid).
1178          */
1179         offset = transport->tcp_offset - sizeof(transport->tcp_xid);
1180         len = sizeof(transport->tcp_calldir) - offset;
1181         dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
1182         p = ((char *) &transport->tcp_calldir) + offset;
1183         used = xdr_skb_read_bits(desc, p, len);
1184         transport->tcp_offset += used;
1185         if (used != len)
1186                 return;
1187         transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
1188         /*
1189          * We don't yet have the XDR buffer, so we will write the calldir
1190          * out after we get the buffer from the 'struct rpc_rqst'
1191          */
1192         switch (ntohl(transport->tcp_calldir)) {
1193         case RPC_REPLY:
1194                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1195                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
1196                 transport->tcp_flags |= TCP_RPC_REPLY;
1197                 break;
1198         case RPC_CALL:
1199                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1200                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
1201                 transport->tcp_flags &= ~TCP_RPC_REPLY;
1202                 break;
1203         default:
1204                 dprintk("RPC:       invalid request message type\n");
1205                 xs_tcp_force_close(&transport->xprt);
1206         }
1207         xs_tcp_check_fraghdr(transport);
1208 }
1209
1210 static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
1211                                      struct xdr_skb_reader *desc,
1212                                      struct rpc_rqst *req)
1213 {
1214         struct sock_xprt *transport =
1215                                 container_of(xprt, struct sock_xprt, xprt);
1216         struct xdr_buf *rcvbuf;
1217         size_t len;
1218         ssize_t r;
1219
1220         rcvbuf = &req->rq_private_buf;
1221
1222         if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
1223                 /*
1224                  * Save the RPC direction in the XDR buffer
1225                  */
1226                 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
1227                         &transport->tcp_calldir,
1228                         sizeof(transport->tcp_calldir));
1229                 transport->tcp_copied += sizeof(transport->tcp_calldir);
1230                 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
1231         }
1232
1233         len = desc->count;
1234         if (len > transport->tcp_reclen - transport->tcp_offset) {
1235                 struct xdr_skb_reader my_desc;
1236
1237                 len = transport->tcp_reclen - transport->tcp_offset;
1238                 memcpy(&my_desc, desc, sizeof(my_desc));
1239                 my_desc.count = len;
1240                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1241                                           &my_desc, xdr_skb_read_bits);
1242                 desc->count -= r;
1243                 desc->offset += r;
1244         } else
1245                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1246                                           desc, xdr_skb_read_bits);
1247
1248         if (r > 0) {
1249                 transport->tcp_copied += r;
1250                 transport->tcp_offset += r;
1251         }
1252         if (r != len) {
1253                 /* Error when copying to the receive buffer,
1254                  * usually because we weren't able to allocate
1255                  * additional buffer pages. All we can do now
1256                  * is turn off TCP_RCV_COPY_DATA, so the request
1257                  * will not receive any additional updates,
1258                  * and time out.
1259                  * Any remaining data from this record will
1260                  * be discarded.
1261                  */
1262                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1263                 dprintk("RPC:       XID %08x truncated request\n",
1264                                 ntohl(transport->tcp_xid));
1265                 dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1266                                 "tcp_offset = %u, tcp_reclen = %u\n",
1267                                 xprt, transport->tcp_copied,
1268                                 transport->tcp_offset, transport->tcp_reclen);
1269                 return;
1270         }
1271
1272         dprintk("RPC:       XID %08x read %Zd bytes\n",
1273                         ntohl(transport->tcp_xid), r);
1274         dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1275                         "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1276                         transport->tcp_offset, transport->tcp_reclen);
1277
1278         if (transport->tcp_copied == req->rq_private_buf.buflen)
1279                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1280         else if (transport->tcp_offset == transport->tcp_reclen) {
1281                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1282                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1283         }
1284 }
1285
1286 /*
1287  * Finds the request corresponding to the RPC xid and invokes the common
1288  * tcp read code to read the data.
1289  */
1290 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1291                                     struct xdr_skb_reader *desc)
1292 {
1293         struct sock_xprt *transport =
1294                                 container_of(xprt, struct sock_xprt, xprt);
1295         struct rpc_rqst *req;
1296
1297         dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1298
1299         /* Find and lock the request corresponding to this xid */
1300         spin_lock(&xprt->transport_lock);
1301         req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1302         if (!req) {
1303                 dprintk("RPC:       XID %08x request not found!\n",
1304                                 ntohl(transport->tcp_xid));
1305                 spin_unlock(&xprt->transport_lock);
1306                 return -1;
1307         }
1308
1309         xs_tcp_read_common(xprt, desc, req);
1310
1311         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1312                 xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1313
1314         spin_unlock(&xprt->transport_lock);
1315         return 0;
1316 }
1317
1318 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1319 /*
1320  * Obtains an rpc_rqst previously allocated and invokes the common
1321  * tcp read code to read the data.  The result is placed in the callback
1322  * queue.
1323  * If we're unable to obtain the rpc_rqst we schedule the closing of the
1324  * connection and return -1.
1325  */
1326 static int xs_tcp_read_callback(struct rpc_xprt *xprt,
1327                                        struct xdr_skb_reader *desc)
1328 {
1329         struct sock_xprt *transport =
1330                                 container_of(xprt, struct sock_xprt, xprt);
1331         struct rpc_rqst *req;
1332
1333         /* Look up and lock the request corresponding to the given XID */
1334         spin_lock(&xprt->transport_lock);
1335         req = xprt_lookup_bc_request(xprt, transport->tcp_xid);
1336         if (req == NULL) {
1337                 spin_unlock(&xprt->transport_lock);
1338                 printk(KERN_WARNING "Callback slot table overflowed\n");
1339                 xprt_force_disconnect(xprt);
1340                 return -1;
1341         }
1342
1343         dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1344         xs_tcp_read_common(xprt, desc, req);
1345
1346         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1347                 xprt_complete_bc_request(req, transport->tcp_copied);
1348         spin_unlock(&xprt->transport_lock);
1349
1350         return 0;
1351 }
1352
1353 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1354                                         struct xdr_skb_reader *desc)
1355 {
1356         struct sock_xprt *transport =
1357                                 container_of(xprt, struct sock_xprt, xprt);
1358
1359         return (transport->tcp_flags & TCP_RPC_REPLY) ?
1360                 xs_tcp_read_reply(xprt, desc) :
1361                 xs_tcp_read_callback(xprt, desc);
1362 }
1363 #else
1364 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1365                                         struct xdr_skb_reader *desc)
1366 {
1367         return xs_tcp_read_reply(xprt, desc);
1368 }
1369 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1370
1371 /*
1372  * Read data off the transport.  This can be either an RPC_CALL or an
1373  * RPC_REPLY.  Relay the processing to helper functions.
1374  */
1375 static void xs_tcp_read_data(struct rpc_xprt *xprt,
1376                                     struct xdr_skb_reader *desc)
1377 {
1378         struct sock_xprt *transport =
1379                                 container_of(xprt, struct sock_xprt, xprt);
1380
1381         if (_xs_tcp_read_data(xprt, desc) == 0)
1382                 xs_tcp_check_fraghdr(transport);
1383         else {
1384                 /*
1385                  * The transport_lock protects the request handling.
1386                  * There's no need to hold it to update the tcp_flags.
1387                  */
1388                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1389         }
1390 }
1391
1392 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1393 {
1394         size_t len;
1395
1396         len = transport->tcp_reclen - transport->tcp_offset;
1397         if (len > desc->count)
1398                 len = desc->count;
1399         desc->count -= len;
1400         desc->offset += len;
1401         transport->tcp_offset += len;
1402         dprintk("RPC:       discarded %Zu bytes\n", len);
1403         xs_tcp_check_fraghdr(transport);
1404 }
1405
1406 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1407 {
1408         struct rpc_xprt *xprt = rd_desc->arg.data;
1409         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1410         struct xdr_skb_reader desc = {
1411                 .skb    = skb,
1412                 .offset = offset,
1413                 .count  = len,
1414         };
1415
1416         dprintk("RPC:       xs_tcp_data_recv started\n");
1417         do {
1418                 /* Read in a new fragment marker if necessary */
1419                 /* Can we ever really expect to get completely empty fragments? */
1420                 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1421                         xs_tcp_read_fraghdr(xprt, &desc);
1422                         continue;
1423                 }
1424                 /* Read in the xid if necessary */
1425                 if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1426                         xs_tcp_read_xid(transport, &desc);
1427                         continue;
1428                 }
1429                 /* Read in the call/reply flag */
1430                 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1431                         xs_tcp_read_calldir(transport, &desc);
1432                         continue;
1433                 }
1434                 /* Read in the request data */
1435                 if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1436                         xs_tcp_read_data(xprt, &desc);
1437                         continue;
1438                 }
1439                 /* Skip over any trailing bytes on short reads */
1440                 xs_tcp_read_discard(transport, &desc);
1441         } while (desc.count);
1442         dprintk("RPC:       xs_tcp_data_recv done\n");
1443         return len - desc.count;
1444 }
1445
1446 /**
1447  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1448  * @sk: socket with data to read
1449  * @bytes: how much data to read
1450  *
1451  */
1452 static void xs_tcp_data_ready(struct sock *sk)
1453 {
1454         struct rpc_xprt *xprt;
1455         read_descriptor_t rd_desc;
1456         int read;
1457
1458         dprintk("RPC:       xs_tcp_data_ready...\n");
1459
1460         read_lock_bh(&sk->sk_callback_lock);
1461         if (!(xprt = xprt_from_sock(sk)))
1462                 goto out;
1463         /* Any data means we had a useful conversation, so
1464          * the we don't need to delay the next reconnect
1465          */
1466         if (xprt->reestablish_timeout)
1467                 xprt->reestablish_timeout = 0;
1468
1469         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1470         rd_desc.arg.data = xprt;
1471         do {
1472                 rd_desc.count = 65536;
1473                 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1474         } while (read > 0);
1475 out:
1476         read_unlock_bh(&sk->sk_callback_lock);
1477 }
1478
1479 /*
1480  * Do the equivalent of linger/linger2 handling for dealing with
1481  * broken servers that don't close the socket in a timely
1482  * fashion
1483  */
1484 static void xs_tcp_schedule_linger_timeout(struct rpc_xprt *xprt,
1485                 unsigned long timeout)
1486 {
1487         struct sock_xprt *transport;
1488
1489         if (xprt_test_and_set_connecting(xprt))
1490                 return;
1491         set_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1492         transport = container_of(xprt, struct sock_xprt, xprt);
1493         queue_delayed_work(rpciod_workqueue, &transport->connect_worker,
1494                            timeout);
1495 }
1496
1497 static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt)
1498 {
1499         struct sock_xprt *transport;
1500
1501         transport = container_of(xprt, struct sock_xprt, xprt);
1502
1503         if (!test_bit(XPRT_CONNECTION_ABORT, &xprt->state) ||
1504             !cancel_delayed_work(&transport->connect_worker))
1505                 return;
1506         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1507         xprt_clear_connecting(xprt);
1508 }
1509
1510 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
1511 {
1512         smp_mb__before_atomic();
1513         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1514         clear_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
1515         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1516         clear_bit(XPRT_CLOSING, &xprt->state);
1517         smp_mb__after_atomic();
1518 }
1519
1520 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
1521 {
1522         xs_sock_reset_connection_flags(xprt);
1523         /* Mark transport as closed and wake up all pending tasks */
1524         xprt_disconnect_done(xprt);
1525 }
1526
1527 /**
1528  * xs_tcp_state_change - callback to handle TCP socket state changes
1529  * @sk: socket whose state has changed
1530  *
1531  */
1532 static void xs_tcp_state_change(struct sock *sk)
1533 {
1534         struct rpc_xprt *xprt;
1535
1536         read_lock_bh(&sk->sk_callback_lock);
1537         if (!(xprt = xprt_from_sock(sk)))
1538                 goto out;
1539         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1540         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1541                         sk->sk_state, xprt_connected(xprt),
1542                         sock_flag(sk, SOCK_DEAD),
1543                         sock_flag(sk, SOCK_ZAPPED),
1544                         sk->sk_shutdown);
1545
1546         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1547         switch (sk->sk_state) {
1548         case TCP_ESTABLISHED:
1549                 spin_lock(&xprt->transport_lock);
1550                 if (!xprt_test_and_set_connected(xprt)) {
1551                         struct sock_xprt *transport = container_of(xprt,
1552                                         struct sock_xprt, xprt);
1553
1554                         /* Reset TCP record info */
1555                         transport->tcp_offset = 0;
1556                         transport->tcp_reclen = 0;
1557                         transport->tcp_copied = 0;
1558                         transport->tcp_flags =
1559                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1560                         xprt->connect_cookie++;
1561
1562                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1563                 }
1564                 spin_unlock(&xprt->transport_lock);
1565                 break;
1566         case TCP_FIN_WAIT1:
1567                 /* The client initiated a shutdown of the socket */
1568                 xprt->connect_cookie++;
1569                 xprt->reestablish_timeout = 0;
1570                 set_bit(XPRT_CLOSING, &xprt->state);
1571                 smp_mb__before_atomic();
1572                 clear_bit(XPRT_CONNECTED, &xprt->state);
1573                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1574                 smp_mb__after_atomic();
1575                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1576                 break;
1577         case TCP_CLOSE_WAIT:
1578                 /* The server initiated a shutdown of the socket */
1579                 xprt->connect_cookie++;
1580                 clear_bit(XPRT_CONNECTED, &xprt->state);
1581                 xs_tcp_force_close(xprt);
1582         case TCP_CLOSING:
1583                 /*
1584                  * If the server closed down the connection, make sure that
1585                  * we back off before reconnecting
1586                  */
1587                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1588                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1589                 break;
1590         case TCP_LAST_ACK:
1591                 set_bit(XPRT_CLOSING, &xprt->state);
1592                 xs_tcp_schedule_linger_timeout(xprt, xs_tcp_fin_timeout);
1593                 smp_mb__before_atomic();
1594                 clear_bit(XPRT_CONNECTED, &xprt->state);
1595                 smp_mb__after_atomic();
1596                 break;
1597         case TCP_CLOSE:
1598                 xs_tcp_cancel_linger_timeout(xprt);
1599                 xs_sock_mark_closed(xprt);
1600         }
1601  out:
1602         read_unlock_bh(&sk->sk_callback_lock);
1603 }
1604
1605 static void xs_write_space(struct sock *sk)
1606 {
1607         struct socket *sock;
1608         struct rpc_xprt *xprt;
1609
1610         if (unlikely(!(sock = sk->sk_socket)))
1611                 return;
1612         clear_bit(SOCK_NOSPACE, &sock->flags);
1613
1614         if (unlikely(!(xprt = xprt_from_sock(sk))))
1615                 return;
1616         if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1617                 return;
1618
1619         xprt_write_space(xprt);
1620 }
1621
1622 /**
1623  * xs_udp_write_space - callback invoked when socket buffer space
1624  *                             becomes available
1625  * @sk: socket whose state has changed
1626  *
1627  * Called when more output buffer space is available for this socket.
1628  * We try not to wake our writers until they can make "significant"
1629  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1630  * with a bunch of small requests.
1631  */
1632 static void xs_udp_write_space(struct sock *sk)
1633 {
1634         read_lock_bh(&sk->sk_callback_lock);
1635
1636         /* from net/core/sock.c:sock_def_write_space */
1637         if (sock_writeable(sk))
1638                 xs_write_space(sk);
1639
1640         read_unlock_bh(&sk->sk_callback_lock);
1641 }
1642
1643 /**
1644  * xs_tcp_write_space - callback invoked when socket buffer space
1645  *                             becomes available
1646  * @sk: socket whose state has changed
1647  *
1648  * Called when more output buffer space is available for this socket.
1649  * We try not to wake our writers until they can make "significant"
1650  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1651  * with a bunch of small requests.
1652  */
1653 static void xs_tcp_write_space(struct sock *sk)
1654 {
1655         read_lock_bh(&sk->sk_callback_lock);
1656
1657         /* from net/core/stream.c:sk_stream_write_space */
1658         if (sk_stream_is_writeable(sk))
1659                 xs_write_space(sk);
1660
1661         read_unlock_bh(&sk->sk_callback_lock);
1662 }
1663
1664 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1665 {
1666         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1667         struct sock *sk = transport->inet;
1668
1669         if (transport->rcvsize) {
1670                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1671                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1672         }
1673         if (transport->sndsize) {
1674                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1675                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1676                 sk->sk_write_space(sk);
1677         }
1678 }
1679
1680 /**
1681  * xs_udp_set_buffer_size - set send and receive limits
1682  * @xprt: generic transport
1683  * @sndsize: requested size of send buffer, in bytes
1684  * @rcvsize: requested size of receive buffer, in bytes
1685  *
1686  * Set socket send and receive buffer size limits.
1687  */
1688 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1689 {
1690         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1691
1692         transport->sndsize = 0;
1693         if (sndsize)
1694                 transport->sndsize = sndsize + 1024;
1695         transport->rcvsize = 0;
1696         if (rcvsize)
1697                 transport->rcvsize = rcvsize + 1024;
1698
1699         xs_udp_do_set_buffer_size(xprt);
1700 }
1701
1702 /**
1703  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1704  * @task: task that timed out
1705  *
1706  * Adjust the congestion window after a retransmit timeout has occurred.
1707  */
1708 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1709 {
1710         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1711 }
1712
1713 static unsigned short xs_get_random_port(void)
1714 {
1715         unsigned short range = xprt_max_resvport - xprt_min_resvport;
1716         unsigned short rand = (unsigned short) prandom_u32() % range;
1717         return rand + xprt_min_resvport;
1718 }
1719
1720 /**
1721  * xs_set_port - reset the port number in the remote endpoint address
1722  * @xprt: generic transport
1723  * @port: new port number
1724  *
1725  */
1726 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1727 {
1728         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1729
1730         rpc_set_port(xs_addr(xprt), port);
1731         xs_update_peer_port(xprt);
1732 }
1733
1734 static unsigned short xs_get_srcport(struct sock_xprt *transport)
1735 {
1736         unsigned short port = transport->srcport;
1737
1738         if (port == 0 && transport->xprt.resvport)
1739                 port = xs_get_random_port();
1740         return port;
1741 }
1742
1743 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1744 {
1745         if (transport->srcport != 0)
1746                 transport->srcport = 0;
1747         if (!transport->xprt.resvport)
1748                 return 0;
1749         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1750                 return xprt_max_resvport;
1751         return --port;
1752 }
1753 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1754 {
1755         struct sockaddr_storage myaddr;
1756         int err, nloop = 0;
1757         unsigned short port = xs_get_srcport(transport);
1758         unsigned short last;
1759
1760         /*
1761          * If we are asking for any ephemeral port (i.e. port == 0 &&
1762          * transport->xprt.resvport == 0), don't bind.  Let the local
1763          * port selection happen implicitly when the socket is used
1764          * (for example at connect time).
1765          *
1766          * This ensures that we can continue to establish TCP
1767          * connections even when all local ephemeral ports are already
1768          * a part of some TCP connection.  This makes no difference
1769          * for UDP sockets, but also doens't harm them.
1770          *
1771          * If we're asking for any reserved port (i.e. port == 0 &&
1772          * transport->xprt.resvport == 1) xs_get_srcport above will
1773          * ensure that port is non-zero and we will bind as needed.
1774          */
1775         if (port == 0)
1776                 return 0;
1777
1778         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1779         do {
1780                 rpc_set_port((struct sockaddr *)&myaddr, port);
1781                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1782                                 transport->xprt.addrlen);
1783                 if (err == 0) {
1784                         transport->srcport = port;
1785                         break;
1786                 }
1787                 last = port;
1788                 port = xs_next_srcport(transport, port);
1789                 if (port > last)
1790                         nloop++;
1791         } while (err == -EADDRINUSE && nloop != 2);
1792
1793         if (myaddr.ss_family == AF_INET)
1794                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1795                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1796                                 port, err ? "failed" : "ok", err);
1797         else
1798                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1799                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1800                                 port, err ? "failed" : "ok", err);
1801         return err;
1802 }
1803
1804 /*
1805  * We don't support autobind on AF_LOCAL sockets
1806  */
1807 static void xs_local_rpcbind(struct rpc_task *task)
1808 {
1809         rcu_read_lock();
1810         xprt_set_bound(rcu_dereference(task->tk_client->cl_xprt));
1811         rcu_read_unlock();
1812 }
1813
1814 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1815 {
1816 }
1817
1818 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1819 static struct lock_class_key xs_key[2];
1820 static struct lock_class_key xs_slock_key[2];
1821
1822 static inline void xs_reclassify_socketu(struct socket *sock)
1823 {
1824         struct sock *sk = sock->sk;
1825
1826         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1827                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1828 }
1829
1830 static inline void xs_reclassify_socket4(struct socket *sock)
1831 {
1832         struct sock *sk = sock->sk;
1833
1834         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1835                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1836 }
1837
1838 static inline void xs_reclassify_socket6(struct socket *sock)
1839 {
1840         struct sock *sk = sock->sk;
1841
1842         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1843                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1844 }
1845
1846 static inline void xs_reclassify_socket(int family, struct socket *sock)
1847 {
1848         WARN_ON_ONCE(sock_owned_by_user(sock->sk));
1849         if (sock_owned_by_user(sock->sk))
1850                 return;
1851
1852         switch (family) {
1853         case AF_LOCAL:
1854                 xs_reclassify_socketu(sock);
1855                 break;
1856         case AF_INET:
1857                 xs_reclassify_socket4(sock);
1858                 break;
1859         case AF_INET6:
1860                 xs_reclassify_socket6(sock);
1861                 break;
1862         }
1863 }
1864 #else
1865 static inline void xs_reclassify_socketu(struct socket *sock)
1866 {
1867 }
1868
1869 static inline void xs_reclassify_socket4(struct socket *sock)
1870 {
1871 }
1872
1873 static inline void xs_reclassify_socket6(struct socket *sock)
1874 {
1875 }
1876
1877 static inline void xs_reclassify_socket(int family, struct socket *sock)
1878 {
1879 }
1880 #endif
1881
1882 static void xs_dummy_setup_socket(struct work_struct *work)
1883 {
1884 }
1885
1886 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1887                 struct sock_xprt *transport, int family, int type, int protocol)
1888 {
1889         struct socket *sock;
1890         int err;
1891
1892         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1893         if (err < 0) {
1894                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1895                                 protocol, -err);
1896                 goto out;
1897         }
1898         xs_reclassify_socket(family, sock);
1899
1900         err = xs_bind(transport, sock);
1901         if (err) {
1902                 sock_release(sock);
1903                 goto out;
1904         }
1905
1906         return sock;
1907 out:
1908         return ERR_PTR(err);
1909 }
1910
1911 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1912                                       struct socket *sock)
1913 {
1914         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1915                                                                         xprt);
1916
1917         if (!transport->inet) {
1918                 struct sock *sk = sock->sk;
1919
1920                 write_lock_bh(&sk->sk_callback_lock);
1921
1922                 xs_save_old_callbacks(transport, sk);
1923
1924                 sk->sk_user_data = xprt;
1925                 sk->sk_data_ready = xs_local_data_ready;
1926                 sk->sk_write_space = xs_udp_write_space;
1927                 sk->sk_error_report = xs_error_report;
1928                 sk->sk_allocation = GFP_ATOMIC;
1929
1930                 xprt_clear_connected(xprt);
1931
1932                 /* Reset to new socket */
1933                 transport->sock = sock;
1934                 transport->inet = sk;
1935
1936                 write_unlock_bh(&sk->sk_callback_lock);
1937         }
1938
1939         /* Tell the socket layer to start connecting... */
1940         xprt->stat.connect_count++;
1941         xprt->stat.connect_start = jiffies;
1942         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1943 }
1944
1945 /**
1946  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1947  * @xprt: RPC transport to connect
1948  * @transport: socket transport to connect
1949  * @create_sock: function to create a socket of the correct type
1950  */
1951 static int xs_local_setup_socket(struct sock_xprt *transport)
1952 {
1953         struct rpc_xprt *xprt = &transport->xprt;
1954         struct socket *sock;
1955         int status = -EIO;
1956
1957         clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
1958         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1959                                         SOCK_STREAM, 0, &sock, 1);
1960         if (status < 0) {
1961                 dprintk("RPC:       can't create AF_LOCAL "
1962                         "transport socket (%d).\n", -status);
1963                 goto out;
1964         }
1965         xs_reclassify_socketu(sock);
1966
1967         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1968                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1969
1970         status = xs_local_finish_connecting(xprt, sock);
1971         trace_rpc_socket_connect(xprt, sock, status);
1972         switch (status) {
1973         case 0:
1974                 dprintk("RPC:       xprt %p connected to %s\n",
1975                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1976                 xprt_set_connected(xprt);
1977         case -ENOBUFS:
1978                 break;
1979         case -ENOENT:
1980                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1981                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1982                 break;
1983         case -ECONNREFUSED:
1984                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1985                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1986                 break;
1987         default:
1988                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1989                                 __func__, -status,
1990                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1991         }
1992
1993 out:
1994         xprt_clear_connecting(xprt);
1995         xprt_wake_pending_tasks(xprt, status);
1996         return status;
1997 }
1998
1999 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2000 {
2001         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2002         int ret;
2003
2004          if (RPC_IS_ASYNC(task)) {
2005                 /*
2006                  * We want the AF_LOCAL connect to be resolved in the
2007                  * filesystem namespace of the process making the rpc
2008                  * call.  Thus we connect synchronously.
2009                  *
2010                  * If we want to support asynchronous AF_LOCAL calls,
2011                  * we'll need to figure out how to pass a namespace to
2012                  * connect.
2013                  */
2014                 rpc_exit(task, -ENOTCONN);
2015                 return;
2016         }
2017         ret = xs_local_setup_socket(transport);
2018         if (ret && !RPC_IS_SOFTCONN(task))
2019                 msleep_interruptible(15000);
2020 }
2021
2022 #ifdef CONFIG_SUNRPC_SWAP
2023 static void xs_set_memalloc(struct rpc_xprt *xprt)
2024 {
2025         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2026                         xprt);
2027
2028         if (xprt->swapper)
2029                 sk_set_memalloc(transport->inet);
2030 }
2031
2032 /**
2033  * xs_swapper - Tag this transport as being used for swap.
2034  * @xprt: transport to tag
2035  * @enable: enable/disable
2036  *
2037  */
2038 int xs_swapper(struct rpc_xprt *xprt, int enable)
2039 {
2040         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
2041                         xprt);
2042         int err = 0;
2043
2044         if (enable) {
2045                 xprt->swapper++;
2046                 xs_set_memalloc(xprt);
2047         } else if (xprt->swapper) {
2048                 xprt->swapper--;
2049                 sk_clear_memalloc(transport->inet);
2050         }
2051
2052         return err;
2053 }
2054 EXPORT_SYMBOL_GPL(xs_swapper);
2055 #else
2056 static void xs_set_memalloc(struct rpc_xprt *xprt)
2057 {
2058 }
2059 #endif
2060
2061 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2062 {
2063         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2064
2065         if (!transport->inet) {
2066                 struct sock *sk = sock->sk;
2067
2068                 write_lock_bh(&sk->sk_callback_lock);
2069
2070                 xs_save_old_callbacks(transport, sk);
2071
2072                 sk->sk_user_data = xprt;
2073                 sk->sk_data_ready = xs_udp_data_ready;
2074                 sk->sk_write_space = xs_udp_write_space;
2075                 sk->sk_allocation = GFP_ATOMIC;
2076
2077                 xprt_set_connected(xprt);
2078
2079                 /* Reset to new socket */
2080                 transport->sock = sock;
2081                 transport->inet = sk;
2082
2083                 xs_set_memalloc(xprt);
2084
2085                 write_unlock_bh(&sk->sk_callback_lock);
2086         }
2087         xs_udp_do_set_buffer_size(xprt);
2088 }
2089
2090 static void xs_udp_setup_socket(struct work_struct *work)
2091 {
2092         struct sock_xprt *transport =
2093                 container_of(work, struct sock_xprt, connect_worker.work);
2094         struct rpc_xprt *xprt = &transport->xprt;
2095         struct socket *sock = transport->sock;
2096         int status = -EIO;
2097
2098         /* Start by resetting any existing state */
2099         xs_reset_transport(transport);
2100         sock = xs_create_sock(xprt, transport,
2101                         xs_addr(xprt)->sa_family, SOCK_DGRAM, IPPROTO_UDP);
2102         if (IS_ERR(sock))
2103                 goto out;
2104
2105         dprintk("RPC:       worker connecting xprt %p via %s to "
2106                                 "%s (port %s)\n", xprt,
2107                         xprt->address_strings[RPC_DISPLAY_PROTO],
2108                         xprt->address_strings[RPC_DISPLAY_ADDR],
2109                         xprt->address_strings[RPC_DISPLAY_PORT]);
2110
2111         xs_udp_finish_connecting(xprt, sock);
2112         trace_rpc_socket_connect(xprt, sock, 0);
2113         status = 0;
2114 out:
2115         xprt_clear_connecting(xprt);
2116         xprt_wake_pending_tasks(xprt, status);
2117 }
2118
2119 /*
2120  * We need to preserve the port number so the reply cache on the server can
2121  * find our cached RPC replies when we get around to reconnecting.
2122  */
2123 static void xs_abort_connection(struct sock_xprt *transport)
2124 {
2125         int result;
2126         struct sockaddr any;
2127
2128         dprintk("RPC:       disconnecting xprt %p to reuse port\n", transport);
2129
2130         /*
2131          * Disconnect the transport socket by doing a connect operation
2132          * with AF_UNSPEC.  This should return immediately...
2133          */
2134         memset(&any, 0, sizeof(any));
2135         any.sa_family = AF_UNSPEC;
2136         result = kernel_connect(transport->sock, &any, sizeof(any), 0);
2137         trace_rpc_socket_reset_connection(&transport->xprt,
2138                         transport->sock, result);
2139         if (!result)
2140                 xs_sock_reset_connection_flags(&transport->xprt);
2141         dprintk("RPC:       AF_UNSPEC connect return code %d\n", result);
2142 }
2143
2144 static void xs_tcp_reuse_connection(struct sock_xprt *transport)
2145 {
2146         unsigned int state = transport->inet->sk_state;
2147
2148         if (state == TCP_CLOSE && transport->sock->state == SS_UNCONNECTED) {
2149                 /* we don't need to abort the connection if the socket
2150                  * hasn't undergone a shutdown
2151                  */
2152                 if (transport->inet->sk_shutdown == 0)
2153                         return;
2154                 dprintk("RPC:       %s: TCP_CLOSEd and sk_shutdown set to %d\n",
2155                                 __func__, transport->inet->sk_shutdown);
2156         }
2157         if ((1 << state) & (TCPF_ESTABLISHED|TCPF_SYN_SENT)) {
2158                 /* we don't need to abort the connection if the socket
2159                  * hasn't undergone a shutdown
2160                  */
2161                 if (transport->inet->sk_shutdown == 0)
2162                         return;
2163                 dprintk("RPC:       %s: ESTABLISHED/SYN_SENT "
2164                                 "sk_shutdown set to %d\n",
2165                                 __func__, transport->inet->sk_shutdown);
2166         }
2167         xs_abort_connection(transport);
2168 }
2169
2170 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2171 {
2172         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2173         int ret = -ENOTCONN;
2174
2175         if (!transport->inet) {
2176                 struct sock *sk = sock->sk;
2177                 unsigned int keepidle = xprt->timeout->to_initval / HZ;
2178                 unsigned int keepcnt = xprt->timeout->to_retries + 1;
2179                 unsigned int opt_on = 1;
2180
2181                 /* TCP Keepalive options */
2182                 kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2183                                 (char *)&opt_on, sizeof(opt_on));
2184                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2185                                 (char *)&keepidle, sizeof(keepidle));
2186                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2187                                 (char *)&keepidle, sizeof(keepidle));
2188                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2189                                 (char *)&keepcnt, sizeof(keepcnt));
2190
2191                 write_lock_bh(&sk->sk_callback_lock);
2192
2193                 xs_save_old_callbacks(transport, sk);
2194
2195                 sk->sk_user_data = xprt;
2196                 sk->sk_data_ready = xs_tcp_data_ready;
2197                 sk->sk_state_change = xs_tcp_state_change;
2198                 sk->sk_write_space = xs_tcp_write_space;
2199                 sk->sk_error_report = xs_error_report;
2200                 sk->sk_allocation = GFP_ATOMIC;
2201
2202                 /* socket options */
2203                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
2204                 sock_reset_flag(sk, SOCK_LINGER);
2205                 tcp_sk(sk)->linger2 = 0;
2206                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2207
2208                 xprt_clear_connected(xprt);
2209
2210                 /* Reset to new socket */
2211                 transport->sock = sock;
2212                 transport->inet = sk;
2213
2214                 write_unlock_bh(&sk->sk_callback_lock);
2215         }
2216
2217         if (!xprt_bound(xprt))
2218                 goto out;
2219
2220         xs_set_memalloc(xprt);
2221
2222         /* Tell the socket layer to start connecting... */
2223         xprt->stat.connect_count++;
2224         xprt->stat.connect_start = jiffies;
2225         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2226         switch (ret) {
2227         case 0:
2228         case -EINPROGRESS:
2229                 /* SYN_SENT! */
2230                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2231                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2232         }
2233 out:
2234         return ret;
2235 }
2236
2237 /**
2238  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2239  * @xprt: RPC transport to connect
2240  * @transport: socket transport to connect
2241  * @create_sock: function to create a socket of the correct type
2242  *
2243  * Invoked by a work queue tasklet.
2244  */
2245 static void xs_tcp_setup_socket(struct work_struct *work)
2246 {
2247         struct sock_xprt *transport =
2248                 container_of(work, struct sock_xprt, connect_worker.work);
2249         struct socket *sock = transport->sock;
2250         struct rpc_xprt *xprt = &transport->xprt;
2251         int status = -EIO;
2252
2253         if (!sock) {
2254                 clear_bit(XPRT_CONNECTION_ABORT, &xprt->state);
2255                 sock = xs_create_sock(xprt, transport,
2256                                 xs_addr(xprt)->sa_family, SOCK_STREAM, IPPROTO_TCP);
2257                 if (IS_ERR(sock)) {
2258                         status = PTR_ERR(sock);
2259                         goto out;
2260                 }
2261         } else {
2262                 int abort_and_exit;
2263
2264                 abort_and_exit = test_and_clear_bit(XPRT_CONNECTION_ABORT,
2265                                 &xprt->state);
2266                 /* "close" the socket, preserving the local port */
2267                 set_bit(XPRT_CONNECTION_REUSE, &xprt->state);
2268                 xs_tcp_reuse_connection(transport);
2269                 clear_bit(XPRT_CONNECTION_REUSE, &xprt->state);
2270
2271                 if (abort_and_exit)
2272                         goto out_eagain;
2273         }
2274
2275         dprintk("RPC:       worker connecting xprt %p via %s to "
2276                                 "%s (port %s)\n", xprt,
2277                         xprt->address_strings[RPC_DISPLAY_PROTO],
2278                         xprt->address_strings[RPC_DISPLAY_ADDR],
2279                         xprt->address_strings[RPC_DISPLAY_PORT]);
2280
2281         status = xs_tcp_finish_connecting(xprt, sock);
2282         trace_rpc_socket_connect(xprt, sock, status);
2283         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2284                         xprt, -status, xprt_connected(xprt),
2285                         sock->sk->sk_state);
2286         switch (status) {
2287         default:
2288                 printk("%s: connect returned unhandled error %d\n",
2289                         __func__, status);
2290         case -EADDRNOTAVAIL:
2291                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2292                  * and retry
2293                  */
2294                 xs_tcp_force_close(xprt);
2295                 break;
2296         case 0:
2297         case -EINPROGRESS:
2298         case -EALREADY:
2299                 xprt_clear_connecting(xprt);
2300                 return;
2301         case -EINVAL:
2302                 /* Happens, for instance, if the user specified a link
2303                  * local IPv6 address without a scope-id.
2304                  */
2305         case -ECONNREFUSED:
2306         case -ECONNRESET:
2307         case -ENETUNREACH:
2308         case -ENOBUFS:
2309                 /* retry with existing socket, after a delay */
2310                 goto out;
2311         }
2312 out_eagain:
2313         status = -EAGAIN;
2314 out:
2315         xprt_clear_connecting(xprt);
2316         xprt_wake_pending_tasks(xprt, status);
2317 }
2318
2319 /**
2320  * xs_connect - connect a socket to a remote endpoint
2321  * @xprt: pointer to transport structure
2322  * @task: address of RPC task that manages state of connect request
2323  *
2324  * TCP: If the remote end dropped the connection, delay reconnecting.
2325  *
2326  * UDP socket connects are synchronous, but we use a work queue anyway
2327  * to guarantee that even unprivileged user processes can set up a
2328  * socket on a privileged port.
2329  *
2330  * If a UDP socket connect fails, the delay behavior here prevents
2331  * retry floods (hard mounts).
2332  */
2333 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2334 {
2335         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2336
2337         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
2338                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2339                                 "seconds\n",
2340                                 xprt, xprt->reestablish_timeout / HZ);
2341                 queue_delayed_work(rpciod_workqueue,
2342                                    &transport->connect_worker,
2343                                    xprt->reestablish_timeout);
2344                 xprt->reestablish_timeout <<= 1;
2345                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2346                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2347                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
2348                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
2349         } else {
2350                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2351                 queue_delayed_work(rpciod_workqueue,
2352                                    &transport->connect_worker, 0);
2353         }
2354 }
2355
2356 /**
2357  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2358  * @xprt: rpc_xprt struct containing statistics
2359  * @seq: output file
2360  *
2361  */
2362 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2363 {
2364         long idle_time = 0;
2365
2366         if (xprt_connected(xprt))
2367                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2368
2369         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2370                         "%llu %llu %lu %llu %llu\n",
2371                         xprt->stat.bind_count,
2372                         xprt->stat.connect_count,
2373                         xprt->stat.connect_time,
2374                         idle_time,
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_udp_print_stats - display UDP socket-specifc stats
2387  * @xprt: rpc_xprt struct containing statistics
2388  * @seq: output file
2389  *
2390  */
2391 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2392 {
2393         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2394
2395         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2396                         "%lu %llu %llu\n",
2397                         transport->srcport,
2398                         xprt->stat.bind_count,
2399                         xprt->stat.sends,
2400                         xprt->stat.recvs,
2401                         xprt->stat.bad_xids,
2402                         xprt->stat.req_u,
2403                         xprt->stat.bklog_u,
2404                         xprt->stat.max_slots,
2405                         xprt->stat.sending_u,
2406                         xprt->stat.pending_u);
2407 }
2408
2409 /**
2410  * xs_tcp_print_stats - display TCP socket-specifc stats
2411  * @xprt: rpc_xprt struct containing statistics
2412  * @seq: output file
2413  *
2414  */
2415 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2416 {
2417         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2418         long idle_time = 0;
2419
2420         if (xprt_connected(xprt))
2421                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2422
2423         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2424                         "%llu %llu %lu %llu %llu\n",
2425                         transport->srcport,
2426                         xprt->stat.bind_count,
2427                         xprt->stat.connect_count,
2428                         xprt->stat.connect_time,
2429                         idle_time,
2430                         xprt->stat.sends,
2431                         xprt->stat.recvs,
2432                         xprt->stat.bad_xids,
2433                         xprt->stat.req_u,
2434                         xprt->stat.bklog_u,
2435                         xprt->stat.max_slots,
2436                         xprt->stat.sending_u,
2437                         xprt->stat.pending_u);
2438 }
2439
2440 /*
2441  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2442  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2443  * to use the server side send routines.
2444  */
2445 static void *bc_malloc(struct rpc_task *task, size_t size)
2446 {
2447         struct page *page;
2448         struct rpc_buffer *buf;
2449
2450         WARN_ON_ONCE(size > PAGE_SIZE - sizeof(struct rpc_buffer));
2451         if (size > PAGE_SIZE - sizeof(struct rpc_buffer))
2452                 return NULL;
2453
2454         page = alloc_page(GFP_KERNEL);
2455         if (!page)
2456                 return NULL;
2457
2458         buf = page_address(page);
2459         buf->len = PAGE_SIZE;
2460
2461         return buf->data;
2462 }
2463
2464 /*
2465  * Free the space allocated in the bc_alloc routine
2466  */
2467 static void bc_free(void *buffer)
2468 {
2469         struct rpc_buffer *buf;
2470
2471         if (!buffer)
2472                 return;
2473
2474         buf = container_of(buffer, struct rpc_buffer, data);
2475         free_page((unsigned long)buf);
2476 }
2477
2478 /*
2479  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2480  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2481  */
2482 static int bc_sendto(struct rpc_rqst *req)
2483 {
2484         int len;
2485         struct xdr_buf *xbufp = &req->rq_snd_buf;
2486         struct rpc_xprt *xprt = req->rq_xprt;
2487         struct sock_xprt *transport =
2488                                 container_of(xprt, struct sock_xprt, xprt);
2489         struct socket *sock = transport->sock;
2490         unsigned long headoff;
2491         unsigned long tailoff;
2492
2493         xs_encode_stream_record_marker(xbufp);
2494
2495         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2496         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2497         len = svc_send_common(sock, xbufp,
2498                               virt_to_page(xbufp->head[0].iov_base), headoff,
2499                               xbufp->tail[0].iov_base, tailoff);
2500
2501         if (len != xbufp->len) {
2502                 printk(KERN_NOTICE "Error sending entire callback!\n");
2503                 len = -EAGAIN;
2504         }
2505
2506         return len;
2507 }
2508
2509 /*
2510  * The send routine. Borrows from svc_send
2511  */
2512 static int bc_send_request(struct rpc_task *task)
2513 {
2514         struct rpc_rqst *req = task->tk_rqstp;
2515         struct svc_xprt *xprt;
2516         u32                     len;
2517
2518         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2519         /*
2520          * Get the server socket associated with this callback xprt
2521          */
2522         xprt = req->rq_xprt->bc_xprt;
2523
2524         /*
2525          * Grab the mutex to serialize data as the connection is shared
2526          * with the fore channel
2527          */
2528         if (!mutex_trylock(&xprt->xpt_mutex)) {
2529                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2530                 if (!mutex_trylock(&xprt->xpt_mutex))
2531                         return -EAGAIN;
2532                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2533         }
2534         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2535                 len = -ENOTCONN;
2536         else
2537                 len = bc_sendto(req);
2538         mutex_unlock(&xprt->xpt_mutex);
2539
2540         if (len > 0)
2541                 len = 0;
2542
2543         return len;
2544 }
2545
2546 /*
2547  * The close routine. Since this is client initiated, we do nothing
2548  */
2549
2550 static void bc_close(struct rpc_xprt *xprt)
2551 {
2552 }
2553
2554 /*
2555  * The xprt destroy routine. Again, because this connection is client
2556  * initiated, we do nothing
2557  */
2558
2559 static void bc_destroy(struct rpc_xprt *xprt)
2560 {
2561         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2562
2563         xs_xprt_free(xprt);
2564         module_put(THIS_MODULE);
2565 }
2566
2567 static struct rpc_xprt_ops xs_local_ops = {
2568         .reserve_xprt           = xprt_reserve_xprt,
2569         .release_xprt           = xs_tcp_release_xprt,
2570         .alloc_slot             = xprt_alloc_slot,
2571         .rpcbind                = xs_local_rpcbind,
2572         .set_port               = xs_local_set_port,
2573         .connect                = xs_local_connect,
2574         .buf_alloc              = rpc_malloc,
2575         .buf_free               = rpc_free,
2576         .send_request           = xs_local_send_request,
2577         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2578         .close                  = xs_close,
2579         .destroy                = xs_destroy,
2580         .print_stats            = xs_local_print_stats,
2581 };
2582
2583 static struct rpc_xprt_ops xs_udp_ops = {
2584         .set_buffer_size        = xs_udp_set_buffer_size,
2585         .reserve_xprt           = xprt_reserve_xprt_cong,
2586         .release_xprt           = xprt_release_xprt_cong,
2587         .alloc_slot             = xprt_alloc_slot,
2588         .rpcbind                = rpcb_getport_async,
2589         .set_port               = xs_set_port,
2590         .connect                = xs_connect,
2591         .buf_alloc              = rpc_malloc,
2592         .buf_free               = rpc_free,
2593         .send_request           = xs_udp_send_request,
2594         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2595         .timer                  = xs_udp_timer,
2596         .release_request        = xprt_release_rqst_cong,
2597         .close                  = xs_close,
2598         .destroy                = xs_destroy,
2599         .print_stats            = xs_udp_print_stats,
2600 };
2601
2602 static struct rpc_xprt_ops xs_tcp_ops = {
2603         .reserve_xprt           = xprt_reserve_xprt,
2604         .release_xprt           = xs_tcp_release_xprt,
2605         .alloc_slot             = xprt_lock_and_alloc_slot,
2606         .rpcbind                = rpcb_getport_async,
2607         .set_port               = xs_set_port,
2608         .connect                = xs_connect,
2609         .buf_alloc              = rpc_malloc,
2610         .buf_free               = rpc_free,
2611         .send_request           = xs_tcp_send_request,
2612         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2613         .close                  = xs_tcp_close,
2614         .destroy                = xs_destroy,
2615         .print_stats            = xs_tcp_print_stats,
2616 };
2617
2618 /*
2619  * The rpc_xprt_ops for the server backchannel
2620  */
2621
2622 static struct rpc_xprt_ops bc_tcp_ops = {
2623         .reserve_xprt           = xprt_reserve_xprt,
2624         .release_xprt           = xprt_release_xprt,
2625         .alloc_slot             = xprt_alloc_slot,
2626         .buf_alloc              = bc_malloc,
2627         .buf_free               = bc_free,
2628         .send_request           = bc_send_request,
2629         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2630         .close                  = bc_close,
2631         .destroy                = bc_destroy,
2632         .print_stats            = xs_tcp_print_stats,
2633 };
2634
2635 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2636 {
2637         static const struct sockaddr_in sin = {
2638                 .sin_family             = AF_INET,
2639                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2640         };
2641         static const struct sockaddr_in6 sin6 = {
2642                 .sin6_family            = AF_INET6,
2643                 .sin6_addr              = IN6ADDR_ANY_INIT,
2644         };
2645
2646         switch (family) {
2647         case AF_LOCAL:
2648                 break;
2649         case AF_INET:
2650                 memcpy(sap, &sin, sizeof(sin));
2651                 break;
2652         case AF_INET6:
2653                 memcpy(sap, &sin6, sizeof(sin6));
2654                 break;
2655         default:
2656                 dprintk("RPC:       %s: Bad address family\n", __func__);
2657                 return -EAFNOSUPPORT;
2658         }
2659         return 0;
2660 }
2661
2662 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2663                                       unsigned int slot_table_size,
2664                                       unsigned int max_slot_table_size)
2665 {
2666         struct rpc_xprt *xprt;
2667         struct sock_xprt *new;
2668
2669         if (args->addrlen > sizeof(xprt->addr)) {
2670                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2671                 return ERR_PTR(-EBADF);
2672         }
2673
2674         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2675                         max_slot_table_size);
2676         if (xprt == NULL) {
2677                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2678                                 "rpc_xprt\n");
2679                 return ERR_PTR(-ENOMEM);
2680         }
2681
2682         new = container_of(xprt, struct sock_xprt, xprt);
2683         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2684         xprt->addrlen = args->addrlen;
2685         if (args->srcaddr)
2686                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2687         else {
2688                 int err;
2689                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2690                                         (struct sockaddr *)&new->srcaddr);
2691                 if (err != 0) {
2692                         xprt_free(xprt);
2693                         return ERR_PTR(err);
2694                 }
2695         }
2696
2697         return xprt;
2698 }
2699
2700 static const struct rpc_timeout xs_local_default_timeout = {
2701         .to_initval = 10 * HZ,
2702         .to_maxval = 10 * HZ,
2703         .to_retries = 2,
2704 };
2705
2706 /**
2707  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2708  * @args: rpc transport creation arguments
2709  *
2710  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2711  */
2712 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2713 {
2714         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2715         struct sock_xprt *transport;
2716         struct rpc_xprt *xprt;
2717         struct rpc_xprt *ret;
2718
2719         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2720                         xprt_max_tcp_slot_table_entries);
2721         if (IS_ERR(xprt))
2722                 return xprt;
2723         transport = container_of(xprt, struct sock_xprt, xprt);
2724
2725         xprt->prot = 0;
2726         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2727         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2728
2729         xprt->bind_timeout = XS_BIND_TO;
2730         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2731         xprt->idle_timeout = XS_IDLE_DISC_TO;
2732
2733         xprt->ops = &xs_local_ops;
2734         xprt->timeout = &xs_local_default_timeout;
2735
2736         INIT_DELAYED_WORK(&transport->connect_worker,
2737                         xs_dummy_setup_socket);
2738
2739         switch (sun->sun_family) {
2740         case AF_LOCAL:
2741                 if (sun->sun_path[0] != '/') {
2742                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2743                                         sun->sun_path);
2744                         ret = ERR_PTR(-EINVAL);
2745                         goto out_err;
2746                 }
2747                 xprt_set_bound(xprt);
2748                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2749                 ret = ERR_PTR(xs_local_setup_socket(transport));
2750                 if (ret)
2751                         goto out_err;
2752                 break;
2753         default:
2754                 ret = ERR_PTR(-EAFNOSUPPORT);
2755                 goto out_err;
2756         }
2757
2758         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2759                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2760
2761         if (try_module_get(THIS_MODULE))
2762                 return xprt;
2763         ret = ERR_PTR(-EINVAL);
2764 out_err:
2765         xs_xprt_free(xprt);
2766         return ret;
2767 }
2768
2769 static const struct rpc_timeout xs_udp_default_timeout = {
2770         .to_initval = 5 * HZ,
2771         .to_maxval = 30 * HZ,
2772         .to_increment = 5 * HZ,
2773         .to_retries = 5,
2774 };
2775
2776 /**
2777  * xs_setup_udp - Set up transport to use a UDP socket
2778  * @args: rpc transport creation arguments
2779  *
2780  */
2781 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2782 {
2783         struct sockaddr *addr = args->dstaddr;
2784         struct rpc_xprt *xprt;
2785         struct sock_xprt *transport;
2786         struct rpc_xprt *ret;
2787
2788         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2789                         xprt_udp_slot_table_entries);
2790         if (IS_ERR(xprt))
2791                 return xprt;
2792         transport = container_of(xprt, struct sock_xprt, xprt);
2793
2794         xprt->prot = IPPROTO_UDP;
2795         xprt->tsh_size = 0;
2796         /* XXX: header size can vary due to auth type, IPv6, etc. */
2797         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2798
2799         xprt->bind_timeout = XS_BIND_TO;
2800         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2801         xprt->idle_timeout = XS_IDLE_DISC_TO;
2802
2803         xprt->ops = &xs_udp_ops;
2804
2805         xprt->timeout = &xs_udp_default_timeout;
2806
2807         switch (addr->sa_family) {
2808         case AF_INET:
2809                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2810                         xprt_set_bound(xprt);
2811
2812                 INIT_DELAYED_WORK(&transport->connect_worker,
2813                                         xs_udp_setup_socket);
2814                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2815                 break;
2816         case AF_INET6:
2817                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2818                         xprt_set_bound(xprt);
2819
2820                 INIT_DELAYED_WORK(&transport->connect_worker,
2821                                         xs_udp_setup_socket);
2822                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2823                 break;
2824         default:
2825                 ret = ERR_PTR(-EAFNOSUPPORT);
2826                 goto out_err;
2827         }
2828
2829         if (xprt_bound(xprt))
2830                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2831                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2832                                 xprt->address_strings[RPC_DISPLAY_PORT],
2833                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2834         else
2835                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2836                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2837                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2838
2839         if (try_module_get(THIS_MODULE))
2840                 return xprt;
2841         ret = ERR_PTR(-EINVAL);
2842 out_err:
2843         xs_xprt_free(xprt);
2844         return ret;
2845 }
2846
2847 static const struct rpc_timeout xs_tcp_default_timeout = {
2848         .to_initval = 60 * HZ,
2849         .to_maxval = 60 * HZ,
2850         .to_retries = 2,
2851 };
2852
2853 /**
2854  * xs_setup_tcp - Set up transport to use a TCP socket
2855  * @args: rpc transport creation arguments
2856  *
2857  */
2858 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2859 {
2860         struct sockaddr *addr = args->dstaddr;
2861         struct rpc_xprt *xprt;
2862         struct sock_xprt *transport;
2863         struct rpc_xprt *ret;
2864         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2865
2866         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2867                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2868
2869         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2870                         max_slot_table_size);
2871         if (IS_ERR(xprt))
2872                 return xprt;
2873         transport = container_of(xprt, struct sock_xprt, xprt);
2874
2875         xprt->prot = IPPROTO_TCP;
2876         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2877         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2878
2879         xprt->bind_timeout = XS_BIND_TO;
2880         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2881         xprt->idle_timeout = XS_IDLE_DISC_TO;
2882
2883         xprt->ops = &xs_tcp_ops;
2884         xprt->timeout = &xs_tcp_default_timeout;
2885
2886         switch (addr->sa_family) {
2887         case AF_INET:
2888                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2889                         xprt_set_bound(xprt);
2890
2891                 INIT_DELAYED_WORK(&transport->connect_worker,
2892                                         xs_tcp_setup_socket);
2893                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2894                 break;
2895         case AF_INET6:
2896                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2897                         xprt_set_bound(xprt);
2898
2899                 INIT_DELAYED_WORK(&transport->connect_worker,
2900                                         xs_tcp_setup_socket);
2901                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2902                 break;
2903         default:
2904                 ret = ERR_PTR(-EAFNOSUPPORT);
2905                 goto out_err;
2906         }
2907
2908         if (xprt_bound(xprt))
2909                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2910                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2911                                 xprt->address_strings[RPC_DISPLAY_PORT],
2912                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2913         else
2914                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2915                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2916                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2917
2918         if (try_module_get(THIS_MODULE))
2919                 return xprt;
2920         ret = ERR_PTR(-EINVAL);
2921 out_err:
2922         xs_xprt_free(xprt);
2923         return ret;
2924 }
2925
2926 /**
2927  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2928  * @args: rpc transport creation arguments
2929  *
2930  */
2931 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2932 {
2933         struct sockaddr *addr = args->dstaddr;
2934         struct rpc_xprt *xprt;
2935         struct sock_xprt *transport;
2936         struct svc_sock *bc_sock;
2937         struct rpc_xprt *ret;
2938
2939         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2940                         xprt_tcp_slot_table_entries);
2941         if (IS_ERR(xprt))
2942                 return xprt;
2943         transport = container_of(xprt, struct sock_xprt, xprt);
2944
2945         xprt->prot = IPPROTO_TCP;
2946         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2947         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2948         xprt->timeout = &xs_tcp_default_timeout;
2949
2950         /* backchannel */
2951         xprt_set_bound(xprt);
2952         xprt->bind_timeout = 0;
2953         xprt->reestablish_timeout = 0;
2954         xprt->idle_timeout = 0;
2955
2956         xprt->ops = &bc_tcp_ops;
2957
2958         switch (addr->sa_family) {
2959         case AF_INET:
2960                 xs_format_peer_addresses(xprt, "tcp",
2961                                          RPCBIND_NETID_TCP);
2962                 break;
2963         case AF_INET6:
2964                 xs_format_peer_addresses(xprt, "tcp",
2965                                    RPCBIND_NETID_TCP6);
2966                 break;
2967         default:
2968                 ret = ERR_PTR(-EAFNOSUPPORT);
2969                 goto out_err;
2970         }
2971
2972         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2973                         xprt->address_strings[RPC_DISPLAY_ADDR],
2974                         xprt->address_strings[RPC_DISPLAY_PORT],
2975                         xprt->address_strings[RPC_DISPLAY_PROTO]);
2976
2977         /*
2978          * Once we've associated a backchannel xprt with a connection,
2979          * we want to keep it around as long as the connection lasts,
2980          * in case we need to start using it for a backchannel again;
2981          * this reference won't be dropped until bc_xprt is destroyed.
2982          */
2983         xprt_get(xprt);
2984         args->bc_xprt->xpt_bc_xprt = xprt;
2985         xprt->bc_xprt = args->bc_xprt;
2986         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2987         transport->sock = bc_sock->sk_sock;
2988         transport->inet = bc_sock->sk_sk;
2989
2990         /*
2991          * Since we don't want connections for the backchannel, we set
2992          * the xprt status to connected
2993          */
2994         xprt_set_connected(xprt);
2995
2996         if (try_module_get(THIS_MODULE))
2997                 return xprt;
2998
2999         args->bc_xprt->xpt_bc_xprt = NULL;
3000         xprt_put(xprt);
3001         ret = ERR_PTR(-EINVAL);
3002 out_err:
3003         xs_xprt_free(xprt);
3004         return ret;
3005 }
3006
3007 static struct xprt_class        xs_local_transport = {
3008         .list           = LIST_HEAD_INIT(xs_local_transport.list),
3009         .name           = "named UNIX socket",
3010         .owner          = THIS_MODULE,
3011         .ident          = XPRT_TRANSPORT_LOCAL,
3012         .setup          = xs_setup_local,
3013 };
3014
3015 static struct xprt_class        xs_udp_transport = {
3016         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
3017         .name           = "udp",
3018         .owner          = THIS_MODULE,
3019         .ident          = XPRT_TRANSPORT_UDP,
3020         .setup          = xs_setup_udp,
3021 };
3022
3023 static struct xprt_class        xs_tcp_transport = {
3024         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
3025         .name           = "tcp",
3026         .owner          = THIS_MODULE,
3027         .ident          = XPRT_TRANSPORT_TCP,
3028         .setup          = xs_setup_tcp,
3029 };
3030
3031 static struct xprt_class        xs_bc_tcp_transport = {
3032         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
3033         .name           = "tcp NFSv4.1 backchannel",
3034         .owner          = THIS_MODULE,
3035         .ident          = XPRT_TRANSPORT_BC_TCP,
3036         .setup          = xs_setup_bc_tcp,
3037 };
3038
3039 /**
3040  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3041  *
3042  */
3043 int init_socket_xprt(void)
3044 {
3045 #ifdef RPC_DEBUG
3046         if (!sunrpc_table_header)
3047                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3048 #endif
3049
3050         xprt_register_transport(&xs_local_transport);
3051         xprt_register_transport(&xs_udp_transport);
3052         xprt_register_transport(&xs_tcp_transport);
3053         xprt_register_transport(&xs_bc_tcp_transport);
3054
3055         return 0;
3056 }
3057
3058 /**
3059  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3060  *
3061  */
3062 void cleanup_socket_xprt(void)
3063 {
3064 #ifdef RPC_DEBUG
3065         if (sunrpc_table_header) {
3066                 unregister_sysctl_table(sunrpc_table_header);
3067                 sunrpc_table_header = NULL;
3068         }
3069 #endif
3070
3071         xprt_unregister_transport(&xs_local_transport);
3072         xprt_unregister_transport(&xs_udp_transport);
3073         xprt_unregister_transport(&xs_tcp_transport);
3074         xprt_unregister_transport(&xs_bc_tcp_transport);
3075 }
3076
3077 static int param_set_uint_minmax(const char *val,
3078                 const struct kernel_param *kp,
3079                 unsigned int min, unsigned int max)
3080 {
3081         unsigned int num;
3082         int ret;
3083
3084         if (!val)
3085                 return -EINVAL;
3086         ret = kstrtouint(val, 0, &num);
3087         if (ret == -EINVAL || num < min || num > max)
3088                 return -EINVAL;
3089         *((unsigned int *)kp->arg) = num;
3090         return 0;
3091 }
3092
3093 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3094 {
3095         return param_set_uint_minmax(val, kp,
3096                         RPC_MIN_RESVPORT,
3097                         RPC_MAX_RESVPORT);
3098 }
3099
3100 static struct kernel_param_ops param_ops_portnr = {
3101         .set = param_set_portnr,
3102         .get = param_get_uint,
3103 };
3104
3105 #define param_check_portnr(name, p) \
3106         __param_check(name, p, unsigned int);
3107
3108 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3109 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3110
3111 static int param_set_slot_table_size(const char *val,
3112                                      const struct kernel_param *kp)
3113 {
3114         return param_set_uint_minmax(val, kp,
3115                         RPC_MIN_SLOT_TABLE,
3116                         RPC_MAX_SLOT_TABLE);
3117 }
3118
3119 static struct kernel_param_ops param_ops_slot_table_size = {
3120         .set = param_set_slot_table_size,
3121         .get = param_get_uint,
3122 };
3123
3124 #define param_check_slot_table_size(name, p) \
3125         __param_check(name, p, unsigned int);
3126
3127 static int param_set_max_slot_table_size(const char *val,
3128                                      const struct kernel_param *kp)
3129 {
3130         return param_set_uint_minmax(val, kp,
3131                         RPC_MIN_SLOT_TABLE,
3132                         RPC_MAX_SLOT_TABLE_LIMIT);
3133 }
3134
3135 static struct kernel_param_ops param_ops_max_slot_table_size = {
3136         .set = param_set_max_slot_table_size,
3137         .get = param_get_uint,
3138 };
3139
3140 #define param_check_max_slot_table_size(name, p) \
3141         __param_check(name, p, unsigned int);
3142
3143 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3144                    slot_table_size, 0644);
3145 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3146                    max_slot_table_size, 0644);
3147 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3148                    slot_table_size, 0644);
3149