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