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
 531         if (status == -EAGAIN && sock_writeable(transport->inet))
 532                 status = -ENOBUFS;
 533
 534         if (likely(sent > 0) || status == 0) {
 535                 req->rq_bytes_sent += sent;
 536                 req->rq_xmit_bytes_sent += sent;
 537                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 538                         req->rq_bytes_sent = 0;
 539                         return 0;
 540                 }
 541                 status = -EAGAIN;
 542         }
 543
 544         switch (status) {
 545         case -ENOBUFS:
 546                 break;
 547         case -EAGAIN:
 548                 status = xs_nospace(task);
 549                 break;
 550         default:
 551                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 552                         -status);
 553         case -EPIPE:
 554                 xs_close(xprt);
 555                 status = -ENOTCONN;
 556         }
 557
 558         return status;
 559 }
 560
 561 /**
 562  * xs_udp_send_request - write an RPC request to a UDP socket
 563  * @task: address of RPC task that manages the state of an RPC request
 564  *
 565  * Return values:
 566  *        0:    The request has been sent
 567  *   EAGAIN:    The socket was blocked, please call again later to
 568  *              complete the request
 569  * ENOTCONN:    Caller needs to invoke connect logic then call again
 570  *    other:    Some other error occurred, the request was not sent
 571  */
 572 static int xs_udp_send_request(struct rpc_task *task)
 573 {
 574         struct rpc_rqst *req = task->tk_rqstp;
 575         struct rpc_xprt *xprt = req->rq_xprt;
 576         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 577         struct xdr_buf *xdr = &req->rq_snd_buf;
 578         int sent = 0;
 579         int status;
 580
 581         xs_pktdump("packet data:",
 582                                 req->rq_svec->iov_base,
 583                                 req->rq_svec->iov_len);
 584
 585         if (!xprt_bound(xprt))
 586                 return -ENOTCONN;
 587         status = xs_sendpages(transport->sock, xs_addr(xprt), xprt->addrlen,
 588                               xdr, req->rq_bytes_sent, true, &sent);
 589
 590         dprintk("RPC:       xs_udp_send_request(%u) = %d\n",
 591                         xdr->len - req->rq_bytes_sent, status);
 592
 593         /* firewall is blocking us, don't return -EAGAIN or we end up looping */
 594         if (status == -EPERM)
 595                 goto process_status;
 596
 597         if (status == -EAGAIN && sock_writeable(transport->inet))
 598                 status = -ENOBUFS;
 599
 600         if (sent > 0 || status == 0) {
 601                 req->rq_xmit_bytes_sent += sent;
 602                 if (sent >= req->rq_slen)
 603                         return 0;
 604                 /* Still some bytes left; set up for a retry later. */
 605                 status = -EAGAIN;
 606         }
 607
 608 process_status:
 609         switch (status) {
 610         case -ENOTSOCK:
 611                 status = -ENOTCONN;
 612                 /* Should we call xs_close() here? */
 613                 break;
 614         case -EAGAIN:
 615                 status = xs_nospace(task);
 616                 break;
 617         default:
 618                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 619                         -status);
 620         case -ENETUNREACH:
 621         case -ENOBUFS:
 622         case -EPIPE:
 623         case -ECONNREFUSED:
 624         case -EPERM:
 625                 /* When the server has died, an ICMP port unreachable message
 626                  * prompts ECONNREFUSED. */
 627                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 628         }
 629
 630         return status;
 631 }
 632
 633 /**
 634  * xs_tcp_send_request - write an RPC request to a TCP socket
 635  * @task: address of RPC task that manages the state of an RPC request
 636  *
 637  * Return values:
 638  *        0:    The request has been sent
 639  *   EAGAIN:    The socket was blocked, please call again later to
 640  *              complete the request
 641  * ENOTCONN:    Caller needs to invoke connect logic then call again
 642  *    other:    Some other error occurred, the request was not sent
 643  *
 644  * XXX: In the case of soft timeouts, should we eventually give up
 645  *      if sendmsg is not able to make progress?
 646  */
 647 static int xs_tcp_send_request(struct rpc_task *task)
 648 {
 649         struct rpc_rqst *req = task->tk_rqstp;
 650         struct rpc_xprt *xprt = req->rq_xprt;
 651         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 652         struct xdr_buf *xdr = &req->rq_snd_buf;
 653         bool zerocopy = true;
 654         int status;
 655         int sent;
 656
 657         xs_encode_stream_record_marker(&req->rq_snd_buf);
 658
 659         xs_pktdump("packet data:",
 660                                 req->rq_svec->iov_base,
 661                                 req->rq_svec->iov_len);
 662         /* Don't use zero copy if this is a resend. If the RPC call
 663          * completes while the socket holds a reference to the pages,
 664          * then we may end up resending corrupted data.
 665          */
 666         if (task->tk_flags & RPC_TASK_SENT)
 667                 zerocopy = false;
 668
 669         /* Continue transmitting the packet/record. We must be careful
 670          * to cope with writespace callbacks arriving _after_ we have
 671          * called sendmsg(). */
 672         while (1) {
 673                 sent = 0;
 674                 status = xs_sendpages(transport->sock, NULL, 0, xdr,
 675                                       req->rq_bytes_sent, zerocopy, &sent);
 676
 677                 dprintk("RPC:       xs_tcp_send_request(%u) = %d\n",
 678                                 xdr->len - req->rq_bytes_sent, status);
 679
 680                 /* If we've sent the entire packet, immediately
 681                  * reset the count of bytes sent. */
 682                 req->rq_bytes_sent += sent;
 683                 req->rq_xmit_bytes_sent += sent;
 684                 if (likely(req->rq_bytes_sent >= req->rq_slen)) {
 685                         req->rq_bytes_sent = 0;
 686                         return 0;
 687                 }
 688
 689                 if (status < 0)
 690                         break;
 691                 if (sent == 0) {
 692                         status = -EAGAIN;
 693                         break;
 694                 }
 695         }
 696         if (status == -EAGAIN && sk_stream_is_writeable(transport->inet))
 697                 status = -ENOBUFS;
 698
 699         switch (status) {
 700         case -ENOTSOCK:
 701                 status = -ENOTCONN;
 702                 /* Should we call xs_close() here? */
 703                 break;
 704         case -EAGAIN:
 705                 status = xs_nospace(task);
 706                 break;
 707         default:
 708                 dprintk("RPC:       sendmsg returned unrecognized error %d\n",
 709                         -status);
 710         case -ECONNRESET:
 711         case -ECONNREFUSED:
 712         case -ENOTCONN:
 713         case -EADDRINUSE:
 714         case -ENOBUFS:
 715         case -EPIPE:
 716                 clear_bit(SOCK_ASYNC_NOSPACE, &transport->sock->flags);
 717         }
 718
 719         return status;
 720 }
 721
 722 /**
 723  * xs_tcp_release_xprt - clean up after a tcp transmission
 724  * @xprt: transport
 725  * @task: rpc task
 726  *
 727  * This cleans up if an error causes us to abort the transmission of a request.
 728  * In this case, the socket may need to be reset in order to avoid confusing
 729  * the server.
 730  */
 731 static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 732 {
 733         struct rpc_rqst *req;
 734
 735         if (task != xprt->snd_task)
 736                 return;
 737         if (task == NULL)
 738                 goto out_release;
 739         req = task->tk_rqstp;
 740         if (req == NULL)
 741                 goto out_release;
 742         if (req->rq_bytes_sent == 0)
 743                 goto out_release;
 744         if (req->rq_bytes_sent == req->rq_snd_buf.len)
 745                 goto out_release;
 746         set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 747 out_release:
 748         xprt_release_xprt(xprt, task);
 749 }
 750
 751 static void xs_save_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 752 {
 753         transport->old_data_ready = sk->sk_data_ready;
 754         transport->old_state_change = sk->sk_state_change;
 755         transport->old_write_space = sk->sk_write_space;
 756         transport->old_error_report = sk->sk_error_report;
 757 }
 758
 759 static void xs_restore_old_callbacks(struct sock_xprt *transport, struct sock *sk)
 760 {
 761         sk->sk_data_ready = transport->old_data_ready;
 762         sk->sk_state_change = transport->old_state_change;
 763         sk->sk_write_space = transport->old_write_space;
 764         sk->sk_error_report = transport->old_error_report;
 765 }
 766
 767 static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt)
 768 {
 769         smp_mb__before_atomic();
 770         clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
 771         clear_bit(XPRT_CLOSING, &xprt->state);
 772         smp_mb__after_atomic();
 773 }
 774
 775 static void xs_sock_mark_closed(struct rpc_xprt *xprt)
 776 {
 777         xs_sock_reset_connection_flags(xprt);
 778         /* Mark transport as closed and wake up all pending tasks */
 779         xprt_disconnect_done(xprt);
 780         xprt_force_disconnect(xprt);
 781 }
 782
 783 /**
 784  * xs_error_report - callback to handle TCP socket state errors
 785  * @sk: socket
 786  *
 787  * Note: we don't call sock_error() since there may be a rpc_task
 788  * using the socket, and so we don't want to clear sk->sk_err.
 789  */
 790 static void xs_error_report(struct sock *sk)
 791 {
 792         struct rpc_xprt *xprt;
 793         int err;
 794
 795         read_lock_bh(&sk->sk_callback_lock);
 796         if (!(xprt = xprt_from_sock(sk)))
 797                 goto out;
 798
 799         err = -sk->sk_err;
 800         if (err == 0)
 801                 goto out;
 802         /* Is this a reset event? */
 803         if (sk->sk_state == TCP_CLOSE)
 804                 xs_sock_mark_closed(xprt);
 805         dprintk("RPC:       xs_error_report client %p, error=%d...\n",
 806                         xprt, -err);
 807         trace_rpc_socket_error(xprt, sk->sk_socket, err);
 808         xprt_wake_pending_tasks(xprt, err);
 809  out:
 810         read_unlock_bh(&sk->sk_callback_lock);
 811 }
 812
 813 static void xs_reset_transport(struct sock_xprt *transport)
 814 {
 815         struct socket *sock = transport->sock;
 816         struct sock *sk = transport->inet;
 817         struct rpc_xprt *xprt = &transport->xprt;
 818
 819         if (sk == NULL)
 820                 return;
 821
 822         if (atomic_read(&transport->xprt.swapper))
 823                 sk_clear_memalloc(sk);
 824
 825         write_lock_bh(&sk->sk_callback_lock);
 826         transport->inet = NULL;
 827         transport->sock = NULL;
 828
 829         sk->sk_user_data = NULL;
 830
 831         xs_restore_old_callbacks(transport, sk);
 832         write_unlock_bh(&sk->sk_callback_lock);
 833         xs_sock_reset_connection_flags(xprt);
 834
 835         trace_rpc_socket_close(xprt, sock);
 836         sock_release(sock);
 837 }
 838
 839 /**
 840  * xs_close - close a socket
 841  * @xprt: transport
 842  *
 843  * This is used when all requests are complete; ie, no DRC state remains
 844  * on the server we want to save.
 845  *
 846  * The caller _must_ be holding XPRT_LOCKED in order to avoid issues with
 847  * xs_reset_transport() zeroing the socket from underneath a writer.
 848  */
 849 static void xs_close(struct rpc_xprt *xprt)
 850 {
 851         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
 852
 853         dprintk("RPC:       xs_close xprt %p\n", xprt);
 854
 855         xs_reset_transport(transport);
 856         xprt->reestablish_timeout = 0;
 857
 858         xprt_disconnect_done(xprt);
 859 }
 860
 861 static void xs_inject_disconnect(struct rpc_xprt *xprt)
 862 {
 863         dprintk("RPC:       injecting transport disconnect on xprt=%p\n",
 864                 xprt);
 865         xprt_disconnect_done(xprt);
 866 }
 867
 868 static void xs_xprt_free(struct rpc_xprt *xprt)
 869 {
 870         xs_free_peer_addresses(xprt);
 871         xprt_free(xprt);
 872 }
 873
 874 /**
 875  * xs_destroy - prepare to shutdown a transport
 876  * @xprt: doomed transport
 877  *
 878  */
 879 static void xs_destroy(struct rpc_xprt *xprt)
 880 {
 881         dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 882
 883         xs_close(xprt);
 884         xs_xprt_free(xprt);
 885         module_put(THIS_MODULE);
 886 }
 887
 888 static int xs_local_copy_to_xdr(struct xdr_buf *xdr, struct sk_buff *skb)
 889 {
 890         struct xdr_skb_reader desc = {
 891                 .skb            = skb,
 892                 .offset         = sizeof(rpc_fraghdr),
 893                 .count          = skb->len - sizeof(rpc_fraghdr),
 894         };
 895
 896         if (xdr_partial_copy_from_skb(xdr, 0, &desc, xdr_skb_read_bits) < 0)
 897                 return -1;
 898         if (desc.count)
 899                 return -1;
 900         return 0;
 901 }
 902
 903 /**
 904  * xs_local_data_ready - "data ready" callback for AF_LOCAL sockets
 905  * @sk: socket with data to read
 906  *
 907  * Currently this assumes we can read the whole reply in a single gulp.
 908  */
 909 static void xs_local_data_ready(struct sock *sk)
 910 {
 911         struct rpc_task *task;
 912         struct rpc_xprt *xprt;
 913         struct rpc_rqst *rovr;
 914         struct sk_buff *skb;
 915         int err, repsize, copied;
 916         u32 _xid;
 917         __be32 *xp;
 918
 919         read_lock_bh(&sk->sk_callback_lock);
 920         dprintk("RPC:       %s...\n", __func__);
 921         xprt = xprt_from_sock(sk);
 922         if (xprt == NULL)
 923                 goto out;
 924
 925         skb = skb_recv_datagram(sk, 0, 1, &err);
 926         if (skb == NULL)
 927                 goto out;
 928
 929         repsize = skb->len - sizeof(rpc_fraghdr);
 930         if (repsize < 4) {
 931                 dprintk("RPC:       impossible RPC reply size %d\n", repsize);
 932                 goto dropit;
 933         }
 934
 935         /* Copy the XID from the skb... */
 936         xp = skb_header_pointer(skb, sizeof(rpc_fraghdr), sizeof(_xid), &_xid);
 937         if (xp == NULL)
 938                 goto dropit;
 939
 940         /* Look up and lock the request corresponding to the given XID */
 941         spin_lock(&xprt->transport_lock);
 942         rovr = xprt_lookup_rqst(xprt, *xp);
 943         if (!rovr)
 944                 goto out_unlock;
 945         task = rovr->rq_task;
 946
 947         copied = rovr->rq_private_buf.buflen;
 948         if (copied > repsize)
 949                 copied = repsize;
 950
 951         if (xs_local_copy_to_xdr(&rovr->rq_private_buf, skb)) {
 952                 dprintk("RPC:       sk_buff copy failed\n");
 953                 goto out_unlock;
 954         }
 955
 956         xprt_complete_rqst(task, copied);
 957
 958  out_unlock:
 959         spin_unlock(&xprt->transport_lock);
 960  dropit:
 961         skb_free_datagram(sk, skb);
 962  out:
 963         read_unlock_bh(&sk->sk_callback_lock);
 964 }
 965
 966 /**
 967  * xs_udp_data_ready - "data ready" callback for UDP sockets
 968  * @sk: socket with data to read
 969  *
 970  */
 971 static void xs_udp_data_ready(struct sock *sk)
 972 {
 973         struct rpc_task *task;
 974         struct rpc_xprt *xprt;
 975         struct rpc_rqst *rovr;
 976         struct sk_buff *skb;
 977         int err, repsize, copied;
 978         u32 _xid;
 979         __be32 *xp;
 980
 981         read_lock_bh(&sk->sk_callback_lock);
 982         dprintk("RPC:       xs_udp_data_ready...\n");
 983         if (!(xprt = xprt_from_sock(sk)))
 984                 goto out;
 985
 986         if ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL)
 987                 goto out;
 988
 989         repsize = skb->len - sizeof(struct udphdr);
 990         if (repsize < 4) {
 991                 dprintk("RPC:       impossible RPC reply size %d!\n", repsize);
 992                 goto dropit;
 993         }
 994
 995         /* Copy the XID from the skb... */
 996         xp = skb_header_pointer(skb, sizeof(struct udphdr),
 997                                 sizeof(_xid), &_xid);
 998         if (xp == NULL)
 999                 goto dropit;
1000
1001         /* Look up and lock the request corresponding to the given XID */
1002         spin_lock(&xprt->transport_lock);
1003         rovr = xprt_lookup_rqst(xprt, *xp);
1004         if (!rovr)
1005                 goto out_unlock;
1006         task = rovr->rq_task;
1007
1008         if ((copied = rovr->rq_private_buf.buflen) > repsize)
1009                 copied = repsize;
1010
1011         /* Suck it into the iovec, verify checksum if not done by hw. */
1012         if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) {
1013                 UDPX_INC_STATS_BH(sk, UDP_MIB_INERRORS);
1014                 goto out_unlock;
1015         }
1016
1017         UDPX_INC_STATS_BH(sk, UDP_MIB_INDATAGRAMS);
1018
1019         xprt_adjust_cwnd(xprt, task, copied);
1020         xprt_complete_rqst(task, copied);
1021
1022  out_unlock:
1023         spin_unlock(&xprt->transport_lock);
1024  dropit:
1025         skb_free_datagram(sk, skb);
1026  out:
1027         read_unlock_bh(&sk->sk_callback_lock);
1028 }
1029
1030 /*
1031  * Helper function to force a TCP close if the server is sending
1032  * junk and/or it has put us in CLOSE_WAIT
1033  */
1034 static void xs_tcp_force_close(struct rpc_xprt *xprt)
1035 {
1036         xprt_force_disconnect(xprt);
1037 }
1038
1039 static inline void xs_tcp_read_fraghdr(struct rpc_xprt *xprt, struct xdr_skb_reader *desc)
1040 {
1041         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1042         size_t len, used;
1043         char *p;
1044
1045         p = ((char *) &transport->tcp_fraghdr) + transport->tcp_offset;
1046         len = sizeof(transport->tcp_fraghdr) - transport->tcp_offset;
1047         used = xdr_skb_read_bits(desc, p, len);
1048         transport->tcp_offset += used;
1049         if (used != len)
1050                 return;
1051
1052         transport->tcp_reclen = ntohl(transport->tcp_fraghdr);
1053         if (transport->tcp_reclen & RPC_LAST_STREAM_FRAGMENT)
1054                 transport->tcp_flags |= TCP_RCV_LAST_FRAG;
1055         else
1056                 transport->tcp_flags &= ~TCP_RCV_LAST_FRAG;
1057         transport->tcp_reclen &= RPC_FRAGMENT_SIZE_MASK;
1058
1059         transport->tcp_flags &= ~TCP_RCV_COPY_FRAGHDR;
1060         transport->tcp_offset = 0;
1061
1062         /* Sanity check of the record length */
1063         if (unlikely(transport->tcp_reclen < 8)) {
1064                 dprintk("RPC:       invalid TCP record fragment length\n");
1065                 xs_tcp_force_close(xprt);
1066                 return;
1067         }
1068         dprintk("RPC:       reading TCP record fragment of length %d\n",
1069                         transport->tcp_reclen);
1070 }
1071
1072 static void xs_tcp_check_fraghdr(struct sock_xprt *transport)
1073 {
1074         if (transport->tcp_offset == transport->tcp_reclen) {
1075                 transport->tcp_flags |= TCP_RCV_COPY_FRAGHDR;
1076                 transport->tcp_offset = 0;
1077                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG) {
1078                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1079                         transport->tcp_flags |= TCP_RCV_COPY_XID;
1080                         transport->tcp_copied = 0;
1081                 }
1082         }
1083 }
1084
1085 static inline void xs_tcp_read_xid(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1086 {
1087         size_t len, used;
1088         char *p;
1089
1090         len = sizeof(transport->tcp_xid) - transport->tcp_offset;
1091         dprintk("RPC:       reading XID (%Zu bytes)\n", len);
1092         p = ((char *) &transport->tcp_xid) + transport->tcp_offset;
1093         used = xdr_skb_read_bits(desc, p, len);
1094         transport->tcp_offset += used;
1095         if (used != len)
1096                 return;
1097         transport->tcp_flags &= ~TCP_RCV_COPY_XID;
1098         transport->tcp_flags |= TCP_RCV_READ_CALLDIR;
1099         transport->tcp_copied = 4;
1100         dprintk("RPC:       reading %s XID %08x\n",
1101                         (transport->tcp_flags & TCP_RPC_REPLY) ? "reply for"
1102                                                               : "request with",
1103                         ntohl(transport->tcp_xid));
1104         xs_tcp_check_fraghdr(transport);
1105 }
1106
1107 static inline void xs_tcp_read_calldir(struct sock_xprt *transport,
1108                                        struct xdr_skb_reader *desc)
1109 {
1110         size_t len, used;
1111         u32 offset;
1112         char *p;
1113
1114         /*
1115          * We want transport->tcp_offset to be 8 at the end of this routine
1116          * (4 bytes for the xid and 4 bytes for the call/reply flag).
1117          * When this function is called for the first time,
1118          * transport->tcp_offset is 4 (after having already read the xid).
1119          */
1120         offset = transport->tcp_offset - sizeof(transport->tcp_xid);
1121         len = sizeof(transport->tcp_calldir) - offset;
1122         dprintk("RPC:       reading CALL/REPLY flag (%Zu bytes)\n", len);
1123         p = ((char *) &transport->tcp_calldir) + offset;
1124         used = xdr_skb_read_bits(desc, p, len);
1125         transport->tcp_offset += used;
1126         if (used != len)
1127                 return;
1128         transport->tcp_flags &= ~TCP_RCV_READ_CALLDIR;
1129         /*
1130          * We don't yet have the XDR buffer, so we will write the calldir
1131          * out after we get the buffer from the 'struct rpc_rqst'
1132          */
1133         switch (ntohl(transport->tcp_calldir)) {
1134         case RPC_REPLY:
1135                 transport->tcp_flags |= TCP_RCV_COPY_CALLDIR;
1136                 transport->tcp_flags |= TCP_RCV_COPY_DATA;
1137                 transport->tcp_flags |= TCP_RPC_REPLY;
1138                 break;
1139         case RPC_CALL:
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         default:
1145                 dprintk("RPC:       invalid request message type\n");
1146                 xs_tcp_force_close(&transport->xprt);
1147         }
1148         xs_tcp_check_fraghdr(transport);
1149 }
1150
1151 static inline void xs_tcp_read_common(struct rpc_xprt *xprt,
1152                                      struct xdr_skb_reader *desc,
1153                                      struct rpc_rqst *req)
1154 {
1155         struct sock_xprt *transport =
1156                                 container_of(xprt, struct sock_xprt, xprt);
1157         struct xdr_buf *rcvbuf;
1158         size_t len;
1159         ssize_t r;
1160
1161         rcvbuf = &req->rq_private_buf;
1162
1163         if (transport->tcp_flags & TCP_RCV_COPY_CALLDIR) {
1164                 /*
1165                  * Save the RPC direction in the XDR buffer
1166                  */
1167                 memcpy(rcvbuf->head[0].iov_base + transport->tcp_copied,
1168                         &transport->tcp_calldir,
1169                         sizeof(transport->tcp_calldir));
1170                 transport->tcp_copied += sizeof(transport->tcp_calldir);
1171                 transport->tcp_flags &= ~TCP_RCV_COPY_CALLDIR;
1172         }
1173
1174         len = desc->count;
1175         if (len > transport->tcp_reclen - transport->tcp_offset) {
1176                 struct xdr_skb_reader my_desc;
1177
1178                 len = transport->tcp_reclen - transport->tcp_offset;
1179                 memcpy(&my_desc, desc, sizeof(my_desc));
1180                 my_desc.count = len;
1181                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1182                                           &my_desc, xdr_skb_read_bits);
1183                 desc->count -= r;
1184                 desc->offset += r;
1185         } else
1186                 r = xdr_partial_copy_from_skb(rcvbuf, transport->tcp_copied,
1187                                           desc, xdr_skb_read_bits);
1188
1189         if (r > 0) {
1190                 transport->tcp_copied += r;
1191                 transport->tcp_offset += r;
1192         }
1193         if (r != len) {
1194                 /* Error when copying to the receive buffer,
1195                  * usually because we weren't able to allocate
1196                  * additional buffer pages. All we can do now
1197                  * is turn off TCP_RCV_COPY_DATA, so the request
1198                  * will not receive any additional updates,
1199                  * and time out.
1200                  * Any remaining data from this record will
1201                  * be discarded.
1202                  */
1203                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1204                 dprintk("RPC:       XID %08x truncated request\n",
1205                                 ntohl(transport->tcp_xid));
1206                 dprintk("RPC:       xprt = %p, tcp_copied = %lu, "
1207                                 "tcp_offset = %u, tcp_reclen = %u\n",
1208                                 xprt, transport->tcp_copied,
1209                                 transport->tcp_offset, transport->tcp_reclen);
1210                 return;
1211         }
1212
1213         dprintk("RPC:       XID %08x read %Zd bytes\n",
1214                         ntohl(transport->tcp_xid), r);
1215         dprintk("RPC:       xprt = %p, tcp_copied = %lu, tcp_offset = %u, "
1216                         "tcp_reclen = %u\n", xprt, transport->tcp_copied,
1217                         transport->tcp_offset, transport->tcp_reclen);
1218
1219         if (transport->tcp_copied == req->rq_private_buf.buflen)
1220                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1221         else if (transport->tcp_offset == transport->tcp_reclen) {
1222                 if (transport->tcp_flags & TCP_RCV_LAST_FRAG)
1223                         transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1224         }
1225 }
1226
1227 /*
1228  * Finds the request corresponding to the RPC xid and invokes the common
1229  * tcp read code to read the data.
1230  */
1231 static inline int xs_tcp_read_reply(struct rpc_xprt *xprt,
1232                                     struct xdr_skb_reader *desc)
1233 {
1234         struct sock_xprt *transport =
1235                                 container_of(xprt, struct sock_xprt, xprt);
1236         struct rpc_rqst *req;
1237
1238         dprintk("RPC:       read reply XID %08x\n", ntohl(transport->tcp_xid));
1239
1240         /* Find and lock the request corresponding to this xid */
1241         spin_lock(&xprt->transport_lock);
1242         req = xprt_lookup_rqst(xprt, transport->tcp_xid);
1243         if (!req) {
1244                 dprintk("RPC:       XID %08x request not found!\n",
1245                                 ntohl(transport->tcp_xid));
1246                 spin_unlock(&xprt->transport_lock);
1247                 return -1;
1248         }
1249
1250         xs_tcp_read_common(xprt, desc, req);
1251
1252         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1253                 xprt_complete_rqst(req->rq_task, transport->tcp_copied);
1254
1255         spin_unlock(&xprt->transport_lock);
1256         return 0;
1257 }
1258
1259 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1260 /*
1261  * Obtains an rpc_rqst previously allocated and invokes the common
1262  * tcp read code to read the data.  The result is placed in the callback
1263  * queue.
1264  * If we're unable to obtain the rpc_rqst we schedule the closing of the
1265  * connection and return -1.
1266  */
1267 static int xs_tcp_read_callback(struct rpc_xprt *xprt,
1268                                        struct xdr_skb_reader *desc)
1269 {
1270         struct sock_xprt *transport =
1271                                 container_of(xprt, struct sock_xprt, xprt);
1272         struct rpc_rqst *req;
1273
1274         /* Look up and lock the request corresponding to the given XID */
1275         spin_lock(&xprt->transport_lock);
1276         req = xprt_lookup_bc_request(xprt, transport->tcp_xid);
1277         if (req == NULL) {
1278                 spin_unlock(&xprt->transport_lock);
1279                 printk(KERN_WARNING "Callback slot table overflowed\n");
1280                 xprt_force_disconnect(xprt);
1281                 return -1;
1282         }
1283
1284         dprintk("RPC:       read callback  XID %08x\n", ntohl(req->rq_xid));
1285         xs_tcp_read_common(xprt, desc, req);
1286
1287         if (!(transport->tcp_flags & TCP_RCV_COPY_DATA))
1288                 xprt_complete_bc_request(req, transport->tcp_copied);
1289         spin_unlock(&xprt->transport_lock);
1290
1291         return 0;
1292 }
1293
1294 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1295                                         struct xdr_skb_reader *desc)
1296 {
1297         struct sock_xprt *transport =
1298                                 container_of(xprt, struct sock_xprt, xprt);
1299
1300         return (transport->tcp_flags & TCP_RPC_REPLY) ?
1301                 xs_tcp_read_reply(xprt, desc) :
1302                 xs_tcp_read_callback(xprt, desc);
1303 }
1304 #else
1305 static inline int _xs_tcp_read_data(struct rpc_xprt *xprt,
1306                                         struct xdr_skb_reader *desc)
1307 {
1308         return xs_tcp_read_reply(xprt, desc);
1309 }
1310 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1311
1312 /*
1313  * Read data off the transport.  This can be either an RPC_CALL or an
1314  * RPC_REPLY.  Relay the processing to helper functions.
1315  */
1316 static void xs_tcp_read_data(struct rpc_xprt *xprt,
1317                                     struct xdr_skb_reader *desc)
1318 {
1319         struct sock_xprt *transport =
1320                                 container_of(xprt, struct sock_xprt, xprt);
1321
1322         if (_xs_tcp_read_data(xprt, desc) == 0)
1323                 xs_tcp_check_fraghdr(transport);
1324         else {
1325                 /*
1326                  * The transport_lock protects the request handling.
1327                  * There's no need to hold it to update the tcp_flags.
1328                  */
1329                 transport->tcp_flags &= ~TCP_RCV_COPY_DATA;
1330         }
1331 }
1332
1333 static inline void xs_tcp_read_discard(struct sock_xprt *transport, struct xdr_skb_reader *desc)
1334 {
1335         size_t len;
1336
1337         len = transport->tcp_reclen - transport->tcp_offset;
1338         if (len > desc->count)
1339                 len = desc->count;
1340         desc->count -= len;
1341         desc->offset += len;
1342         transport->tcp_offset += len;
1343         dprintk("RPC:       discarded %Zu bytes\n", len);
1344         xs_tcp_check_fraghdr(transport);
1345 }
1346
1347 static int xs_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, unsigned int offset, size_t len)
1348 {
1349         struct rpc_xprt *xprt = rd_desc->arg.data;
1350         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1351         struct xdr_skb_reader desc = {
1352                 .skb    = skb,
1353                 .offset = offset,
1354                 .count  = len,
1355         };
1356
1357         dprintk("RPC:       xs_tcp_data_recv started\n");
1358         do {
1359                 trace_xs_tcp_data_recv(transport);
1360                 /* Read in a new fragment marker if necessary */
1361                 /* Can we ever really expect to get completely empty fragments? */
1362                 if (transport->tcp_flags & TCP_RCV_COPY_FRAGHDR) {
1363                         xs_tcp_read_fraghdr(xprt, &desc);
1364                         continue;
1365                 }
1366                 /* Read in the xid if necessary */
1367                 if (transport->tcp_flags & TCP_RCV_COPY_XID) {
1368                         xs_tcp_read_xid(transport, &desc);
1369                         continue;
1370                 }
1371                 /* Read in the call/reply flag */
1372                 if (transport->tcp_flags & TCP_RCV_READ_CALLDIR) {
1373                         xs_tcp_read_calldir(transport, &desc);
1374                         continue;
1375                 }
1376                 /* Read in the request data */
1377                 if (transport->tcp_flags & TCP_RCV_COPY_DATA) {
1378                         xs_tcp_read_data(xprt, &desc);
1379                         continue;
1380                 }
1381                 /* Skip over any trailing bytes on short reads */
1382                 xs_tcp_read_discard(transport, &desc);
1383         } while (desc.count);
1384         trace_xs_tcp_data_recv(transport);
1385         dprintk("RPC:       xs_tcp_data_recv done\n");
1386         return len - desc.count;
1387 }
1388
1389 /**
1390  * xs_tcp_data_ready - "data ready" callback for TCP sockets
1391  * @sk: socket with data to read
1392  *
1393  */
1394 static void xs_tcp_data_ready(struct sock *sk)
1395 {
1396         struct rpc_xprt *xprt;
1397         read_descriptor_t rd_desc;
1398         int read;
1399         unsigned long total = 0;
1400
1401         dprintk("RPC:       xs_tcp_data_ready...\n");
1402
1403         read_lock_bh(&sk->sk_callback_lock);
1404         if (!(xprt = xprt_from_sock(sk))) {
1405                 read = 0;
1406                 goto out;
1407         }
1408         /* Any data means we had a useful conversation, so
1409          * the we don't need to delay the next reconnect
1410          */
1411         if (xprt->reestablish_timeout)
1412                 xprt->reestablish_timeout = 0;
1413
1414         /* We use rd_desc to pass struct xprt to xs_tcp_data_recv */
1415         rd_desc.arg.data = xprt;
1416         do {
1417                 rd_desc.count = 65536;
1418                 read = tcp_read_sock(sk, &rd_desc, xs_tcp_data_recv);
1419                 if (read > 0)
1420                         total += read;
1421         } while (read > 0);
1422 out:
1423         trace_xs_tcp_data_ready(xprt, read, total);
1424         read_unlock_bh(&sk->sk_callback_lock);
1425 }
1426
1427 /**
1428  * xs_tcp_state_change - callback to handle TCP socket state changes
1429  * @sk: socket whose state has changed
1430  *
1431  */
1432 static void xs_tcp_state_change(struct sock *sk)
1433 {
1434         struct rpc_xprt *xprt;
1435
1436         read_lock_bh(&sk->sk_callback_lock);
1437         if (!(xprt = xprt_from_sock(sk)))
1438                 goto out;
1439         dprintk("RPC:       xs_tcp_state_change client %p...\n", xprt);
1440         dprintk("RPC:       state %x conn %d dead %d zapped %d sk_shutdown %d\n",
1441                         sk->sk_state, xprt_connected(xprt),
1442                         sock_flag(sk, SOCK_DEAD),
1443                         sock_flag(sk, SOCK_ZAPPED),
1444                         sk->sk_shutdown);
1445
1446         trace_rpc_socket_state_change(xprt, sk->sk_socket);
1447         switch (sk->sk_state) {
1448         case TCP_ESTABLISHED:
1449                 spin_lock(&xprt->transport_lock);
1450                 if (!xprt_test_and_set_connected(xprt)) {
1451                         struct sock_xprt *transport = container_of(xprt,
1452                                         struct sock_xprt, xprt);
1453
1454                         /* Reset TCP record info */
1455                         transport->tcp_offset = 0;
1456                         transport->tcp_reclen = 0;
1457                         transport->tcp_copied = 0;
1458                         transport->tcp_flags =
1459                                 TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
1460                         xprt->connect_cookie++;
1461
1462                         xprt_wake_pending_tasks(xprt, -EAGAIN);
1463                 }
1464                 spin_unlock(&xprt->transport_lock);
1465                 break;
1466         case TCP_FIN_WAIT1:
1467                 /* The client initiated a shutdown of the socket */
1468                 xprt->connect_cookie++;
1469                 xprt->reestablish_timeout = 0;
1470                 set_bit(XPRT_CLOSING, &xprt->state);
1471                 smp_mb__before_atomic();
1472                 clear_bit(XPRT_CONNECTED, &xprt->state);
1473                 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
1474                 smp_mb__after_atomic();
1475                 break;
1476         case TCP_CLOSE_WAIT:
1477                 /* The server initiated a shutdown of the socket */
1478                 xprt->connect_cookie++;
1479                 clear_bit(XPRT_CONNECTED, &xprt->state);
1480                 xs_tcp_force_close(xprt);
1481         case TCP_CLOSING:
1482                 /*
1483                  * If the server closed down the connection, make sure that
1484                  * we back off before reconnecting
1485                  */
1486                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
1487                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
1488                 break;
1489         case TCP_LAST_ACK:
1490                 set_bit(XPRT_CLOSING, &xprt->state);
1491                 smp_mb__before_atomic();
1492                 clear_bit(XPRT_CONNECTED, &xprt->state);
1493                 smp_mb__after_atomic();
1494                 break;
1495         case TCP_CLOSE:
1496                 xs_sock_mark_closed(xprt);
1497         }
1498  out:
1499         read_unlock_bh(&sk->sk_callback_lock);
1500 }
1501
1502 static void xs_write_space(struct sock *sk)
1503 {
1504         struct socket *sock;
1505         struct rpc_xprt *xprt;
1506
1507         if (unlikely(!(sock = sk->sk_socket)))
1508                 return;
1509         clear_bit(SOCK_NOSPACE, &sock->flags);
1510
1511         if (unlikely(!(xprt = xprt_from_sock(sk))))
1512                 return;
1513         if (test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags) == 0)
1514                 return;
1515
1516         xprt_write_space(xprt);
1517 }
1518
1519 /**
1520  * xs_udp_write_space - callback invoked when socket buffer space
1521  *                             becomes available
1522  * @sk: socket whose state has changed
1523  *
1524  * Called when more output buffer space is available for this socket.
1525  * We try not to wake our writers until they can make "significant"
1526  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1527  * with a bunch of small requests.
1528  */
1529 static void xs_udp_write_space(struct sock *sk)
1530 {
1531         read_lock_bh(&sk->sk_callback_lock);
1532
1533         /* from net/core/sock.c:sock_def_write_space */
1534         if (sock_writeable(sk))
1535                 xs_write_space(sk);
1536
1537         read_unlock_bh(&sk->sk_callback_lock);
1538 }
1539
1540 /**
1541  * xs_tcp_write_space - callback invoked when socket buffer space
1542  *                             becomes available
1543  * @sk: socket whose state has changed
1544  *
1545  * Called when more output buffer space is available for this socket.
1546  * We try not to wake our writers until they can make "significant"
1547  * progress, otherwise we'll waste resources thrashing kernel_sendmsg
1548  * with a bunch of small requests.
1549  */
1550 static void xs_tcp_write_space(struct sock *sk)
1551 {
1552         read_lock_bh(&sk->sk_callback_lock);
1553
1554         /* from net/core/stream.c:sk_stream_write_space */
1555         if (sk_stream_is_writeable(sk))
1556                 xs_write_space(sk);
1557
1558         read_unlock_bh(&sk->sk_callback_lock);
1559 }
1560
1561 static void xs_udp_do_set_buffer_size(struct rpc_xprt *xprt)
1562 {
1563         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1564         struct sock *sk = transport->inet;
1565
1566         if (transport->rcvsize) {
1567                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1568                 sk->sk_rcvbuf = transport->rcvsize * xprt->max_reqs * 2;
1569         }
1570         if (transport->sndsize) {
1571                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1572                 sk->sk_sndbuf = transport->sndsize * xprt->max_reqs * 2;
1573                 sk->sk_write_space(sk);
1574         }
1575 }
1576
1577 /**
1578  * xs_udp_set_buffer_size - set send and receive limits
1579  * @xprt: generic transport
1580  * @sndsize: requested size of send buffer, in bytes
1581  * @rcvsize: requested size of receive buffer, in bytes
1582  *
1583  * Set socket send and receive buffer size limits.
1584  */
1585 static void xs_udp_set_buffer_size(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize)
1586 {
1587         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1588
1589         transport->sndsize = 0;
1590         if (sndsize)
1591                 transport->sndsize = sndsize + 1024;
1592         transport->rcvsize = 0;
1593         if (rcvsize)
1594                 transport->rcvsize = rcvsize + 1024;
1595
1596         xs_udp_do_set_buffer_size(xprt);
1597 }
1598
1599 /**
1600  * xs_udp_timer - called when a retransmit timeout occurs on a UDP transport
1601  * @task: task that timed out
1602  *
1603  * Adjust the congestion window after a retransmit timeout has occurred.
1604  */
1605 static void xs_udp_timer(struct rpc_xprt *xprt, struct rpc_task *task)
1606 {
1607         xprt_adjust_cwnd(xprt, task, -ETIMEDOUT);
1608 }
1609
1610 static unsigned short xs_get_random_port(void)
1611 {
1612         unsigned short range = xprt_max_resvport - xprt_min_resvport;
1613         unsigned short rand = (unsigned short) prandom_u32() % range;
1614         return rand + xprt_min_resvport;
1615 }
1616
1617 /**
1618  * xs_set_reuseaddr_port - set the socket's port and address reuse options
1619  * @sock: socket
1620  *
1621  * Note that this function has to be called on all sockets that share the
1622  * same port, and it must be called before binding.
1623  */
1624 static void xs_sock_set_reuseport(struct socket *sock)
1625 {
1626         int opt = 1;
1627
1628         kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEPORT,
1629                         (char *)&opt, sizeof(opt));
1630 }
1631
1632 static unsigned short xs_sock_getport(struct socket *sock)
1633 {
1634         struct sockaddr_storage buf;
1635         int buflen;
1636         unsigned short port = 0;
1637
1638         if (kernel_getsockname(sock, (struct sockaddr *)&buf, &buflen) < 0)
1639                 goto out;
1640         switch (buf.ss_family) {
1641         case AF_INET6:
1642                 port = ntohs(((struct sockaddr_in6 *)&buf)->sin6_port);
1643                 break;
1644         case AF_INET:
1645                 port = ntohs(((struct sockaddr_in *)&buf)->sin_port);
1646         }
1647 out:
1648         return port;
1649 }
1650
1651 /**
1652  * xs_set_port - reset the port number in the remote endpoint address
1653  * @xprt: generic transport
1654  * @port: new port number
1655  *
1656  */
1657 static void xs_set_port(struct rpc_xprt *xprt, unsigned short port)
1658 {
1659         dprintk("RPC:       setting port for xprt %p to %u\n", xprt, port);
1660
1661         rpc_set_port(xs_addr(xprt), port);
1662         xs_update_peer_port(xprt);
1663 }
1664
1665 static void xs_set_srcport(struct sock_xprt *transport, struct socket *sock)
1666 {
1667         if (transport->srcport == 0)
1668                 transport->srcport = xs_sock_getport(sock);
1669 }
1670
1671 static unsigned short xs_get_srcport(struct sock_xprt *transport)
1672 {
1673         unsigned short port = transport->srcport;
1674
1675         if (port == 0 && transport->xprt.resvport)
1676                 port = xs_get_random_port();
1677         return port;
1678 }
1679
1680 static unsigned short xs_next_srcport(struct sock_xprt *transport, unsigned short port)
1681 {
1682         if (transport->srcport != 0)
1683                 transport->srcport = 0;
1684         if (!transport->xprt.resvport)
1685                 return 0;
1686         if (port <= xprt_min_resvport || port > xprt_max_resvport)
1687                 return xprt_max_resvport;
1688         return --port;
1689 }
1690 static int xs_bind(struct sock_xprt *transport, struct socket *sock)
1691 {
1692         struct sockaddr_storage myaddr;
1693         int err, nloop = 0;
1694         unsigned short port = xs_get_srcport(transport);
1695         unsigned short last;
1696
1697         /*
1698          * If we are asking for any ephemeral port (i.e. port == 0 &&
1699          * transport->xprt.resvport == 0), don't bind.  Let the local
1700          * port selection happen implicitly when the socket is used
1701          * (for example at connect time).
1702          *
1703          * This ensures that we can continue to establish TCP
1704          * connections even when all local ephemeral ports are already
1705          * a part of some TCP connection.  This makes no difference
1706          * for UDP sockets, but also doens't harm them.
1707          *
1708          * If we're asking for any reserved port (i.e. port == 0 &&
1709          * transport->xprt.resvport == 1) xs_get_srcport above will
1710          * ensure that port is non-zero and we will bind as needed.
1711          */
1712         if (port == 0)
1713                 return 0;
1714
1715         memcpy(&myaddr, &transport->srcaddr, transport->xprt.addrlen);
1716         do {
1717                 rpc_set_port((struct sockaddr *)&myaddr, port);
1718                 err = kernel_bind(sock, (struct sockaddr *)&myaddr,
1719                                 transport->xprt.addrlen);
1720                 if (err == 0) {
1721                         transport->srcport = port;
1722                         break;
1723                 }
1724                 last = port;
1725                 port = xs_next_srcport(transport, port);
1726                 if (port > last)
1727                         nloop++;
1728         } while (err == -EADDRINUSE && nloop != 2);
1729
1730         if (myaddr.ss_family == AF_INET)
1731                 dprintk("RPC:       %s %pI4:%u: %s (%d)\n", __func__,
1732                                 &((struct sockaddr_in *)&myaddr)->sin_addr,
1733                                 port, err ? "failed" : "ok", err);
1734         else
1735                 dprintk("RPC:       %s %pI6:%u: %s (%d)\n", __func__,
1736                                 &((struct sockaddr_in6 *)&myaddr)->sin6_addr,
1737                                 port, err ? "failed" : "ok", err);
1738         return err;
1739 }
1740
1741 /*
1742  * We don't support autobind on AF_LOCAL sockets
1743  */
1744 static void xs_local_rpcbind(struct rpc_task *task)
1745 {
1746         rcu_read_lock();
1747         xprt_set_bound(rcu_dereference(task->tk_client->cl_xprt));
1748         rcu_read_unlock();
1749 }
1750
1751 static void xs_local_set_port(struct rpc_xprt *xprt, unsigned short port)
1752 {
1753 }
1754
1755 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1756 static struct lock_class_key xs_key[2];
1757 static struct lock_class_key xs_slock_key[2];
1758
1759 static inline void xs_reclassify_socketu(struct socket *sock)
1760 {
1761         struct sock *sk = sock->sk;
1762
1763         sock_lock_init_class_and_name(sk, "slock-AF_LOCAL-RPC",
1764                 &xs_slock_key[1], "sk_lock-AF_LOCAL-RPC", &xs_key[1]);
1765 }
1766
1767 static inline void xs_reclassify_socket4(struct socket *sock)
1768 {
1769         struct sock *sk = sock->sk;
1770
1771         sock_lock_init_class_and_name(sk, "slock-AF_INET-RPC",
1772                 &xs_slock_key[0], "sk_lock-AF_INET-RPC", &xs_key[0]);
1773 }
1774
1775 static inline void xs_reclassify_socket6(struct socket *sock)
1776 {
1777         struct sock *sk = sock->sk;
1778
1779         sock_lock_init_class_and_name(sk, "slock-AF_INET6-RPC",
1780                 &xs_slock_key[1], "sk_lock-AF_INET6-RPC", &xs_key[1]);
1781 }
1782
1783 static inline void xs_reclassify_socket(int family, struct socket *sock)
1784 {
1785         WARN_ON_ONCE(sock_owned_by_user(sock->sk));
1786         if (sock_owned_by_user(sock->sk))
1787                 return;
1788
1789         switch (family) {
1790         case AF_LOCAL:
1791                 xs_reclassify_socketu(sock);
1792                 break;
1793         case AF_INET:
1794                 xs_reclassify_socket4(sock);
1795                 break;
1796         case AF_INET6:
1797                 xs_reclassify_socket6(sock);
1798                 break;
1799         }
1800 }
1801 #else
1802 static inline void xs_reclassify_socketu(struct socket *sock)
1803 {
1804 }
1805
1806 static inline void xs_reclassify_socket4(struct socket *sock)
1807 {
1808 }
1809
1810 static inline void xs_reclassify_socket6(struct socket *sock)
1811 {
1812 }
1813
1814 static inline void xs_reclassify_socket(int family, struct socket *sock)
1815 {
1816 }
1817 #endif
1818
1819 static void xs_dummy_setup_socket(struct work_struct *work)
1820 {
1821 }
1822
1823 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
1824                 struct sock_xprt *transport, int family, int type,
1825                 int protocol, bool reuseport)
1826 {
1827         struct socket *sock;
1828         int err;
1829
1830         err = __sock_create(xprt->xprt_net, family, type, protocol, &sock, 1);
1831         if (err < 0) {
1832                 dprintk("RPC:       can't create %d transport socket (%d).\n",
1833                                 protocol, -err);
1834                 goto out;
1835         }
1836         xs_reclassify_socket(family, sock);
1837
1838         if (reuseport)
1839                 xs_sock_set_reuseport(sock);
1840
1841         err = xs_bind(transport, sock);
1842         if (err) {
1843                 sock_release(sock);
1844                 goto out;
1845         }
1846
1847         return sock;
1848 out:
1849         return ERR_PTR(err);
1850 }
1851
1852 static int xs_local_finish_connecting(struct rpc_xprt *xprt,
1853                                       struct socket *sock)
1854 {
1855         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1856                                                                         xprt);
1857
1858         if (!transport->inet) {
1859                 struct sock *sk = sock->sk;
1860
1861                 write_lock_bh(&sk->sk_callback_lock);
1862
1863                 xs_save_old_callbacks(transport, sk);
1864
1865                 sk->sk_user_data = xprt;
1866                 sk->sk_data_ready = xs_local_data_ready;
1867                 sk->sk_write_space = xs_udp_write_space;
1868                 sk->sk_error_report = xs_error_report;
1869                 sk->sk_allocation = GFP_ATOMIC;
1870
1871                 xprt_clear_connected(xprt);
1872
1873                 /* Reset to new socket */
1874                 transport->sock = sock;
1875                 transport->inet = sk;
1876
1877                 write_unlock_bh(&sk->sk_callback_lock);
1878         }
1879
1880         /* Tell the socket layer to start connecting... */
1881         xprt->stat.connect_count++;
1882         xprt->stat.connect_start = jiffies;
1883         return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
1884 }
1885
1886 /**
1887  * xs_local_setup_socket - create AF_LOCAL socket, connect to a local endpoint
1888  * @transport: socket transport to connect
1889  */
1890 static int xs_local_setup_socket(struct sock_xprt *transport)
1891 {
1892         struct rpc_xprt *xprt = &transport->xprt;
1893         struct socket *sock;
1894         int status = -EIO;
1895
1896         status = __sock_create(xprt->xprt_net, AF_LOCAL,
1897                                         SOCK_STREAM, 0, &sock, 1);
1898         if (status < 0) {
1899                 dprintk("RPC:       can't create AF_LOCAL "
1900                         "transport socket (%d).\n", -status);
1901                 goto out;
1902         }
1903         xs_reclassify_socketu(sock);
1904
1905         dprintk("RPC:       worker connecting xprt %p via AF_LOCAL to %s\n",
1906                         xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1907
1908         status = xs_local_finish_connecting(xprt, sock);
1909         trace_rpc_socket_connect(xprt, sock, status);
1910         switch (status) {
1911         case 0:
1912                 dprintk("RPC:       xprt %p connected to %s\n",
1913                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1914                 xprt_set_connected(xprt);
1915         case -ENOBUFS:
1916                 break;
1917         case -ENOENT:
1918                 dprintk("RPC:       xprt %p: socket %s does not exist\n",
1919                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1920                 break;
1921         case -ECONNREFUSED:
1922                 dprintk("RPC:       xprt %p: connection refused for %s\n",
1923                                 xprt, xprt->address_strings[RPC_DISPLAY_ADDR]);
1924                 break;
1925         default:
1926                 printk(KERN_ERR "%s: unhandled error (%d) connecting to %s\n",
1927                                 __func__, -status,
1928                                 xprt->address_strings[RPC_DISPLAY_ADDR]);
1929         }
1930
1931 out:
1932         xprt_clear_connecting(xprt);
1933         xprt_wake_pending_tasks(xprt, status);
1934         return status;
1935 }
1936
1937 static void xs_local_connect(struct rpc_xprt *xprt, struct rpc_task *task)
1938 {
1939         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
1940         int ret;
1941
1942          if (RPC_IS_ASYNC(task)) {
1943                 /*
1944                  * We want the AF_LOCAL connect to be resolved in the
1945                  * filesystem namespace of the process making the rpc
1946                  * call.  Thus we connect synchronously.
1947                  *
1948                  * If we want to support asynchronous AF_LOCAL calls,
1949                  * we'll need to figure out how to pass a namespace to
1950                  * connect.
1951                  */
1952                 rpc_exit(task, -ENOTCONN);
1953                 return;
1954         }
1955         ret = xs_local_setup_socket(transport);
1956         if (ret && !RPC_IS_SOFTCONN(task))
1957                 msleep_interruptible(15000);
1958 }
1959
1960 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
1961 /*
1962  * Note that this should be called with XPRT_LOCKED held (or when we otherwise
1963  * know that we have exclusive access to the socket), to guard against
1964  * races with xs_reset_transport.
1965  */
1966 static void xs_set_memalloc(struct rpc_xprt *xprt)
1967 {
1968         struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
1969                         xprt);
1970
1971         /*
1972          * If there's no sock, then we have nothing to set. The
1973          * reconnecting process will get it for us.
1974          */
1975         if (!transport->inet)
1976                 return;
1977         if (atomic_read(&xprt->swapper))
1978                 sk_set_memalloc(transport->inet);
1979 }
1980
1981 /**
1982  * xs_enable_swap - Tag this transport as being used for swap.
1983  * @xprt: transport to tag
1984  *
1985  * Take a reference to this transport on behalf of the rpc_clnt, and
1986  * optionally mark it for swapping if it wasn't already.
1987  */
1988 static int
1989 xs_enable_swap(struct rpc_xprt *xprt)
1990 {
1991         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
1992
1993         if (atomic_inc_return(&xprt->swapper) != 1)
1994                 return 0;
1995         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
1996                 return -ERESTARTSYS;
1997         if (xs->inet)
1998                 sk_set_memalloc(xs->inet);
1999         xprt_release_xprt(xprt, NULL);
2000         return 0;
2001 }
2002
2003 /**
2004  * xs_disable_swap - Untag this transport as being used for swap.
2005  * @xprt: transport to tag
2006  *
2007  * Drop a "swapper" reference to this xprt on behalf of the rpc_clnt. If the
2008  * swapper refcount goes to 0, untag the socket as a memalloc socket.
2009  */
2010 static void
2011 xs_disable_swap(struct rpc_xprt *xprt)
2012 {
2013         struct sock_xprt *xs = container_of(xprt, struct sock_xprt, xprt);
2014
2015         if (!atomic_dec_and_test(&xprt->swapper))
2016                 return;
2017         if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE))
2018                 return;
2019         if (xs->inet)
2020                 sk_clear_memalloc(xs->inet);
2021         xprt_release_xprt(xprt, NULL);
2022 }
2023 #else
2024 static void xs_set_memalloc(struct rpc_xprt *xprt)
2025 {
2026 }
2027
2028 static int
2029 xs_enable_swap(struct rpc_xprt *xprt)
2030 {
2031         return -EINVAL;
2032 }
2033
2034 static void
2035 xs_disable_swap(struct rpc_xprt *xprt)
2036 {
2037 }
2038 #endif
2039
2040 static void xs_udp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2041 {
2042         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2043
2044         if (!transport->inet) {
2045                 struct sock *sk = sock->sk;
2046
2047                 write_lock_bh(&sk->sk_callback_lock);
2048
2049                 xs_save_old_callbacks(transport, sk);
2050
2051                 sk->sk_user_data = xprt;
2052                 sk->sk_data_ready = xs_udp_data_ready;
2053                 sk->sk_write_space = xs_udp_write_space;
2054                 sk->sk_allocation = GFP_ATOMIC;
2055
2056                 xprt_set_connected(xprt);
2057
2058                 /* Reset to new socket */
2059                 transport->sock = sock;
2060                 transport->inet = sk;
2061
2062                 xs_set_memalloc(xprt);
2063
2064                 write_unlock_bh(&sk->sk_callback_lock);
2065         }
2066         xs_udp_do_set_buffer_size(xprt);
2067 }
2068
2069 static void xs_udp_setup_socket(struct work_struct *work)
2070 {
2071         struct sock_xprt *transport =
2072                 container_of(work, struct sock_xprt, connect_worker.work);
2073         struct rpc_xprt *xprt = &transport->xprt;
2074         struct socket *sock = transport->sock;
2075         int status = -EIO;
2076
2077         sock = xs_create_sock(xprt, transport,
2078                         xs_addr(xprt)->sa_family, SOCK_DGRAM,
2079                         IPPROTO_UDP, false);
2080         if (IS_ERR(sock))
2081                 goto out;
2082
2083         dprintk("RPC:       worker connecting xprt %p via %s to "
2084                                 "%s (port %s)\n", xprt,
2085                         xprt->address_strings[RPC_DISPLAY_PROTO],
2086                         xprt->address_strings[RPC_DISPLAY_ADDR],
2087                         xprt->address_strings[RPC_DISPLAY_PORT]);
2088
2089         xs_udp_finish_connecting(xprt, sock);
2090         trace_rpc_socket_connect(xprt, sock, 0);
2091         status = 0;
2092 out:
2093         xprt_unlock_connect(xprt, transport);
2094         xprt_clear_connecting(xprt);
2095         xprt_wake_pending_tasks(xprt, status);
2096 }
2097
2098 /**
2099  * xs_tcp_shutdown - gracefully shut down a TCP socket
2100  * @xprt: transport
2101  *
2102  * Initiates a graceful shutdown of the TCP socket by calling the
2103  * equivalent of shutdown(SHUT_RDWR);
2104  */
2105 static void xs_tcp_shutdown(struct rpc_xprt *xprt)
2106 {
2107         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2108         struct socket *sock = transport->sock;
2109
2110         if (sock == NULL)
2111                 return;
2112         if (xprt_connected(xprt)) {
2113                 kernel_sock_shutdown(sock, SHUT_RDWR);
2114                 trace_rpc_socket_shutdown(xprt, sock);
2115         } else
2116                 xs_reset_transport(transport);
2117 }
2118
2119 static int xs_tcp_finish_connecting(struct rpc_xprt *xprt, struct socket *sock)
2120 {
2121         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2122         int ret = -ENOTCONN;
2123
2124         if (!transport->inet) {
2125                 struct sock *sk = sock->sk;
2126                 unsigned int keepidle = xprt->timeout->to_initval / HZ;
2127                 unsigned int keepcnt = xprt->timeout->to_retries + 1;
2128                 unsigned int opt_on = 1;
2129                 unsigned int timeo;
2130
2131                 /* TCP Keepalive options */
2132                 kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
2133                                 (char *)&opt_on, sizeof(opt_on));
2134                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
2135                                 (char *)&keepidle, sizeof(keepidle));
2136                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
2137                                 (char *)&keepidle, sizeof(keepidle));
2138                 kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
2139                                 (char *)&keepcnt, sizeof(keepcnt));
2140
2141                 /* TCP user timeout (see RFC5482) */
2142                 timeo = jiffies_to_msecs(xprt->timeout->to_initval) *
2143                         (xprt->timeout->to_retries + 1);
2144                 kernel_setsockopt(sock, SOL_TCP, TCP_USER_TIMEOUT,
2145                                 (char *)&timeo, sizeof(timeo));
2146
2147                 write_lock_bh(&sk->sk_callback_lock);
2148
2149                 xs_save_old_callbacks(transport, sk);
2150
2151                 sk->sk_user_data = xprt;
2152                 sk->sk_data_ready = xs_tcp_data_ready;
2153                 sk->sk_state_change = xs_tcp_state_change;
2154                 sk->sk_write_space = xs_tcp_write_space;
2155                 sk->sk_error_report = xs_error_report;
2156                 sk->sk_allocation = GFP_ATOMIC;
2157
2158                 /* socket options */
2159                 sock_reset_flag(sk, SOCK_LINGER);
2160                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
2161
2162                 xprt_clear_connected(xprt);
2163
2164                 /* Reset to new socket */
2165                 transport->sock = sock;
2166                 transport->inet = sk;
2167
2168                 write_unlock_bh(&sk->sk_callback_lock);
2169         }
2170
2171         if (!xprt_bound(xprt))
2172                 goto out;
2173
2174         xs_set_memalloc(xprt);
2175
2176         /* Tell the socket layer to start connecting... */
2177         xprt->stat.connect_count++;
2178         xprt->stat.connect_start = jiffies;
2179         ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK);
2180         switch (ret) {
2181         case 0:
2182                 xs_set_srcport(transport, sock);
2183         case -EINPROGRESS:
2184                 /* SYN_SENT! */
2185                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2186                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2187         }
2188 out:
2189         return ret;
2190 }
2191
2192 /**
2193  * xs_tcp_setup_socket - create a TCP socket and connect to a remote endpoint
2194  *
2195  * Invoked by a work queue tasklet.
2196  */
2197 static void xs_tcp_setup_socket(struct work_struct *work)
2198 {
2199         struct sock_xprt *transport =
2200                 container_of(work, struct sock_xprt, connect_worker.work);
2201         struct socket *sock = transport->sock;
2202         struct rpc_xprt *xprt = &transport->xprt;
2203         int status = -EIO;
2204
2205         if (!sock) {
2206                 sock = xs_create_sock(xprt, transport,
2207                                 xs_addr(xprt)->sa_family, SOCK_STREAM,
2208                                 IPPROTO_TCP, true);
2209                 if (IS_ERR(sock)) {
2210                         status = PTR_ERR(sock);
2211                         goto out;
2212                 }
2213         }
2214
2215         dprintk("RPC:       worker connecting xprt %p via %s to "
2216                                 "%s (port %s)\n", xprt,
2217                         xprt->address_strings[RPC_DISPLAY_PROTO],
2218                         xprt->address_strings[RPC_DISPLAY_ADDR],
2219                         xprt->address_strings[RPC_DISPLAY_PORT]);
2220
2221         status = xs_tcp_finish_connecting(xprt, sock);
2222         trace_rpc_socket_connect(xprt, sock, status);
2223         dprintk("RPC:       %p connect status %d connected %d sock state %d\n",
2224                         xprt, -status, xprt_connected(xprt),
2225                         sock->sk->sk_state);
2226         switch (status) {
2227         default:
2228                 printk("%s: connect returned unhandled error %d\n",
2229                         __func__, status);
2230         case -EADDRNOTAVAIL:
2231                 /* We're probably in TIME_WAIT. Get rid of existing socket,
2232                  * and retry
2233                  */
2234                 xs_tcp_force_close(xprt);
2235                 break;
2236         case 0:
2237         case -EINPROGRESS:
2238         case -EALREADY:
2239                 xprt_unlock_connect(xprt, transport);
2240                 xprt_clear_connecting(xprt);
2241                 return;
2242         case -EINVAL:
2243                 /* Happens, for instance, if the user specified a link
2244                  * local IPv6 address without a scope-id.
2245                  */
2246         case -ECONNREFUSED:
2247         case -ECONNRESET:
2248         case -ENETUNREACH:
2249         case -EADDRINUSE:
2250         case -ENOBUFS:
2251                 /* retry with existing socket, after a delay */
2252                 xs_tcp_force_close(xprt);
2253                 goto out;
2254         }
2255         status = -EAGAIN;
2256 out:
2257         xprt_unlock_connect(xprt, transport);
2258         xprt_clear_connecting(xprt);
2259         xprt_wake_pending_tasks(xprt, status);
2260 }
2261
2262 /**
2263  * xs_connect - connect a socket to a remote endpoint
2264  * @xprt: pointer to transport structure
2265  * @task: address of RPC task that manages state of connect request
2266  *
2267  * TCP: If the remote end dropped the connection, delay reconnecting.
2268  *
2269  * UDP socket connects are synchronous, but we use a work queue anyway
2270  * to guarantee that even unprivileged user processes can set up a
2271  * socket on a privileged port.
2272  *
2273  * If a UDP socket connect fails, the delay behavior here prevents
2274  * retry floods (hard mounts).
2275  */
2276 static void xs_connect(struct rpc_xprt *xprt, struct rpc_task *task)
2277 {
2278         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2279
2280         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, transport));
2281
2282         /* Start by resetting any existing state */
2283         xs_reset_transport(transport);
2284
2285         if (transport->sock != NULL && !RPC_IS_SOFTCONN(task)) {
2286                 dprintk("RPC:       xs_connect delayed xprt %p for %lu "
2287                                 "seconds\n",
2288                                 xprt, xprt->reestablish_timeout / HZ);
2289                 queue_delayed_work(rpciod_workqueue,
2290                                    &transport->connect_worker,
2291                                    xprt->reestablish_timeout);
2292                 xprt->reestablish_timeout <<= 1;
2293                 if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
2294                         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2295                 if (xprt->reestablish_timeout > XS_TCP_MAX_REEST_TO)
2296                         xprt->reestablish_timeout = XS_TCP_MAX_REEST_TO;
2297         } else {
2298                 dprintk("RPC:       xs_connect scheduled xprt %p\n", xprt);
2299                 queue_delayed_work(rpciod_workqueue,
2300                                    &transport->connect_worker, 0);
2301         }
2302 }
2303
2304 /**
2305  * xs_local_print_stats - display AF_LOCAL socket-specifc stats
2306  * @xprt: rpc_xprt struct containing statistics
2307  * @seq: output file
2308  *
2309  */
2310 static void xs_local_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2311 {
2312         long idle_time = 0;
2313
2314         if (xprt_connected(xprt))
2315                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2316
2317         seq_printf(seq, "\txprt:\tlocal %lu %lu %lu %ld %lu %lu %lu "
2318                         "%llu %llu %lu %llu %llu\n",
2319                         xprt->stat.bind_count,
2320                         xprt->stat.connect_count,
2321                         xprt->stat.connect_time,
2322                         idle_time,
2323                         xprt->stat.sends,
2324                         xprt->stat.recvs,
2325                         xprt->stat.bad_xids,
2326                         xprt->stat.req_u,
2327                         xprt->stat.bklog_u,
2328                         xprt->stat.max_slots,
2329                         xprt->stat.sending_u,
2330                         xprt->stat.pending_u);
2331 }
2332
2333 /**
2334  * xs_udp_print_stats - display UDP socket-specifc stats
2335  * @xprt: rpc_xprt struct containing statistics
2336  * @seq: output file
2337  *
2338  */
2339 static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2340 {
2341         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2342
2343         seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %llu %llu "
2344                         "%lu %llu %llu\n",
2345                         transport->srcport,
2346                         xprt->stat.bind_count,
2347                         xprt->stat.sends,
2348                         xprt->stat.recvs,
2349                         xprt->stat.bad_xids,
2350                         xprt->stat.req_u,
2351                         xprt->stat.bklog_u,
2352                         xprt->stat.max_slots,
2353                         xprt->stat.sending_u,
2354                         xprt->stat.pending_u);
2355 }
2356
2357 /**
2358  * xs_tcp_print_stats - display TCP socket-specifc stats
2359  * @xprt: rpc_xprt struct containing statistics
2360  * @seq: output file
2361  *
2362  */
2363 static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
2364 {
2365         struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
2366         long idle_time = 0;
2367
2368         if (xprt_connected(xprt))
2369                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
2370
2371         seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu "
2372                         "%llu %llu %lu %llu %llu\n",
2373                         transport->srcport,
2374                         xprt->stat.bind_count,
2375                         xprt->stat.connect_count,
2376                         xprt->stat.connect_time,
2377                         idle_time,
2378                         xprt->stat.sends,
2379                         xprt->stat.recvs,
2380                         xprt->stat.bad_xids,
2381                         xprt->stat.req_u,
2382                         xprt->stat.bklog_u,
2383                         xprt->stat.max_slots,
2384                         xprt->stat.sending_u,
2385                         xprt->stat.pending_u);
2386 }
2387
2388 /*
2389  * Allocate a bunch of pages for a scratch buffer for the rpc code. The reason
2390  * we allocate pages instead doing a kmalloc like rpc_malloc is because we want
2391  * to use the server side send routines.
2392  */
2393 static void *bc_malloc(struct rpc_task *task, size_t size)
2394 {
2395         struct page *page;
2396         struct rpc_buffer *buf;
2397
2398         WARN_ON_ONCE(size > PAGE_SIZE - sizeof(struct rpc_buffer));
2399         if (size > PAGE_SIZE - sizeof(struct rpc_buffer))
2400                 return NULL;
2401
2402         page = alloc_page(GFP_KERNEL);
2403         if (!page)
2404                 return NULL;
2405
2406         buf = page_address(page);
2407         buf->len = PAGE_SIZE;
2408
2409         return buf->data;
2410 }
2411
2412 /*
2413  * Free the space allocated in the bc_alloc routine
2414  */
2415 static void bc_free(void *buffer)
2416 {
2417         struct rpc_buffer *buf;
2418
2419         if (!buffer)
2420                 return;
2421
2422         buf = container_of(buffer, struct rpc_buffer, data);
2423         free_page((unsigned long)buf);
2424 }
2425
2426 /*
2427  * Use the svc_sock to send the callback. Must be called with svsk->sk_mutex
2428  * held. Borrows heavily from svc_tcp_sendto and xs_tcp_send_request.
2429  */
2430 static int bc_sendto(struct rpc_rqst *req)
2431 {
2432         int len;
2433         struct xdr_buf *xbufp = &req->rq_snd_buf;
2434         struct rpc_xprt *xprt = req->rq_xprt;
2435         struct sock_xprt *transport =
2436                                 container_of(xprt, struct sock_xprt, xprt);
2437         struct socket *sock = transport->sock;
2438         unsigned long headoff;
2439         unsigned long tailoff;
2440
2441         xs_encode_stream_record_marker(xbufp);
2442
2443         tailoff = (unsigned long)xbufp->tail[0].iov_base & ~PAGE_MASK;
2444         headoff = (unsigned long)xbufp->head[0].iov_base & ~PAGE_MASK;
2445         len = svc_send_common(sock, xbufp,
2446                               virt_to_page(xbufp->head[0].iov_base), headoff,
2447                               xbufp->tail[0].iov_base, tailoff);
2448
2449         if (len != xbufp->len) {
2450                 printk(KERN_NOTICE "Error sending entire callback!\n");
2451                 len = -EAGAIN;
2452         }
2453
2454         return len;
2455 }
2456
2457 /*
2458  * The send routine. Borrows from svc_send
2459  */
2460 static int bc_send_request(struct rpc_task *task)
2461 {
2462         struct rpc_rqst *req = task->tk_rqstp;
2463         struct svc_xprt *xprt;
2464         u32                     len;
2465
2466         dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
2467         /*
2468          * Get the server socket associated with this callback xprt
2469          */
2470         xprt = req->rq_xprt->bc_xprt;
2471
2472         /*
2473          * Grab the mutex to serialize data as the connection is shared
2474          * with the fore channel
2475          */
2476         if (!mutex_trylock(&xprt->xpt_mutex)) {
2477                 rpc_sleep_on(&xprt->xpt_bc_pending, task, NULL);
2478                 if (!mutex_trylock(&xprt->xpt_mutex))
2479                         return -EAGAIN;
2480                 rpc_wake_up_queued_task(&xprt->xpt_bc_pending, task);
2481         }
2482         if (test_bit(XPT_DEAD, &xprt->xpt_flags))
2483                 len = -ENOTCONN;
2484         else
2485                 len = bc_sendto(req);
2486         mutex_unlock(&xprt->xpt_mutex);
2487
2488         if (len > 0)
2489                 len = 0;
2490
2491         return len;
2492 }
2493
2494 /*
2495  * The close routine. Since this is client initiated, we do nothing
2496  */
2497
2498 static void bc_close(struct rpc_xprt *xprt)
2499 {
2500 }
2501
2502 /*
2503  * The xprt destroy routine. Again, because this connection is client
2504  * initiated, we do nothing
2505  */
2506
2507 static void bc_destroy(struct rpc_xprt *xprt)
2508 {
2509         dprintk("RPC:       bc_destroy xprt %p\n", xprt);
2510
2511         xs_xprt_free(xprt);
2512         module_put(THIS_MODULE);
2513 }
2514
2515 static struct rpc_xprt_ops xs_local_ops = {
2516         .reserve_xprt           = xprt_reserve_xprt,
2517         .release_xprt           = xs_tcp_release_xprt,
2518         .alloc_slot             = xprt_alloc_slot,
2519         .rpcbind                = xs_local_rpcbind,
2520         .set_port               = xs_local_set_port,
2521         .connect                = xs_local_connect,
2522         .buf_alloc              = rpc_malloc,
2523         .buf_free               = rpc_free,
2524         .send_request           = xs_local_send_request,
2525         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2526         .close                  = xs_close,
2527         .destroy                = xs_destroy,
2528         .print_stats            = xs_local_print_stats,
2529         .enable_swap            = xs_enable_swap,
2530         .disable_swap           = xs_disable_swap,
2531 };
2532
2533 static struct rpc_xprt_ops xs_udp_ops = {
2534         .set_buffer_size        = xs_udp_set_buffer_size,
2535         .reserve_xprt           = xprt_reserve_xprt_cong,
2536         .release_xprt           = xprt_release_xprt_cong,
2537         .alloc_slot             = xprt_alloc_slot,
2538         .rpcbind                = rpcb_getport_async,
2539         .set_port               = xs_set_port,
2540         .connect                = xs_connect,
2541         .buf_alloc              = rpc_malloc,
2542         .buf_free               = rpc_free,
2543         .send_request           = xs_udp_send_request,
2544         .set_retrans_timeout    = xprt_set_retrans_timeout_rtt,
2545         .timer                  = xs_udp_timer,
2546         .release_request        = xprt_release_rqst_cong,
2547         .close                  = xs_close,
2548         .destroy                = xs_destroy,
2549         .print_stats            = xs_udp_print_stats,
2550         .enable_swap            = xs_enable_swap,
2551         .disable_swap           = xs_disable_swap,
2552         .inject_disconnect      = xs_inject_disconnect,
2553 };
2554
2555 static struct rpc_xprt_ops xs_tcp_ops = {
2556         .reserve_xprt           = xprt_reserve_xprt,
2557         .release_xprt           = xs_tcp_release_xprt,
2558         .alloc_slot             = xprt_lock_and_alloc_slot,
2559         .rpcbind                = rpcb_getport_async,
2560         .set_port               = xs_set_port,
2561         .connect                = xs_connect,
2562         .buf_alloc              = rpc_malloc,
2563         .buf_free               = rpc_free,
2564         .send_request           = xs_tcp_send_request,
2565         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2566         .close                  = xs_tcp_shutdown,
2567         .destroy                = xs_destroy,
2568         .print_stats            = xs_tcp_print_stats,
2569         .enable_swap            = xs_enable_swap,
2570         .disable_swap           = xs_disable_swap,
2571         .inject_disconnect      = xs_inject_disconnect,
2572 };
2573
2574 /*
2575  * The rpc_xprt_ops for the server backchannel
2576  */
2577
2578 static struct rpc_xprt_ops bc_tcp_ops = {
2579         .reserve_xprt           = xprt_reserve_xprt,
2580         .release_xprt           = xprt_release_xprt,
2581         .alloc_slot             = xprt_alloc_slot,
2582         .buf_alloc              = bc_malloc,
2583         .buf_free               = bc_free,
2584         .send_request           = bc_send_request,
2585         .set_retrans_timeout    = xprt_set_retrans_timeout_def,
2586         .close                  = bc_close,
2587         .destroy                = bc_destroy,
2588         .print_stats            = xs_tcp_print_stats,
2589         .enable_swap            = xs_enable_swap,
2590         .disable_swap           = xs_disable_swap,
2591         .inject_disconnect      = xs_inject_disconnect,
2592 };
2593
2594 static int xs_init_anyaddr(const int family, struct sockaddr *sap)
2595 {
2596         static const struct sockaddr_in sin = {
2597                 .sin_family             = AF_INET,
2598                 .sin_addr.s_addr        = htonl(INADDR_ANY),
2599         };
2600         static const struct sockaddr_in6 sin6 = {
2601                 .sin6_family            = AF_INET6,
2602                 .sin6_addr              = IN6ADDR_ANY_INIT,
2603         };
2604
2605         switch (family) {
2606         case AF_LOCAL:
2607                 break;
2608         case AF_INET:
2609                 memcpy(sap, &sin, sizeof(sin));
2610                 break;
2611         case AF_INET6:
2612                 memcpy(sap, &sin6, sizeof(sin6));
2613                 break;
2614         default:
2615                 dprintk("RPC:       %s: Bad address family\n", __func__);
2616                 return -EAFNOSUPPORT;
2617         }
2618         return 0;
2619 }
2620
2621 static struct rpc_xprt *xs_setup_xprt(struct xprt_create *args,
2622                                       unsigned int slot_table_size,
2623                                       unsigned int max_slot_table_size)
2624 {
2625         struct rpc_xprt *xprt;
2626         struct sock_xprt *new;
2627
2628         if (args->addrlen > sizeof(xprt->addr)) {
2629                 dprintk("RPC:       xs_setup_xprt: address too large\n");
2630                 return ERR_PTR(-EBADF);
2631         }
2632
2633         xprt = xprt_alloc(args->net, sizeof(*new), slot_table_size,
2634                         max_slot_table_size);
2635         if (xprt == NULL) {
2636                 dprintk("RPC:       xs_setup_xprt: couldn't allocate "
2637                                 "rpc_xprt\n");
2638                 return ERR_PTR(-ENOMEM);
2639         }
2640
2641         new = container_of(xprt, struct sock_xprt, xprt);
2642         memcpy(&xprt->addr, args->dstaddr, args->addrlen);
2643         xprt->addrlen = args->addrlen;
2644         if (args->srcaddr)
2645                 memcpy(&new->srcaddr, args->srcaddr, args->addrlen);
2646         else {
2647                 int err;
2648                 err = xs_init_anyaddr(args->dstaddr->sa_family,
2649                                         (struct sockaddr *)&new->srcaddr);
2650                 if (err != 0) {
2651                         xprt_free(xprt);
2652                         return ERR_PTR(err);
2653                 }
2654         }
2655
2656         return xprt;
2657 }
2658
2659 static const struct rpc_timeout xs_local_default_timeout = {
2660         .to_initval = 10 * HZ,
2661         .to_maxval = 10 * HZ,
2662         .to_retries = 2,
2663 };
2664
2665 /**
2666  * xs_setup_local - Set up transport to use an AF_LOCAL socket
2667  * @args: rpc transport creation arguments
2668  *
2669  * AF_LOCAL is a "tpi_cots_ord" transport, just like TCP
2670  */
2671 static struct rpc_xprt *xs_setup_local(struct xprt_create *args)
2672 {
2673         struct sockaddr_un *sun = (struct sockaddr_un *)args->dstaddr;
2674         struct sock_xprt *transport;
2675         struct rpc_xprt *xprt;
2676         struct rpc_xprt *ret;
2677
2678         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2679                         xprt_max_tcp_slot_table_entries);
2680         if (IS_ERR(xprt))
2681                 return xprt;
2682         transport = container_of(xprt, struct sock_xprt, xprt);
2683
2684         xprt->prot = 0;
2685         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2686         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2687
2688         xprt->bind_timeout = XS_BIND_TO;
2689         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2690         xprt->idle_timeout = XS_IDLE_DISC_TO;
2691
2692         xprt->ops = &xs_local_ops;
2693         xprt->timeout = &xs_local_default_timeout;
2694
2695         INIT_DELAYED_WORK(&transport->connect_worker,
2696                         xs_dummy_setup_socket);
2697
2698         switch (sun->sun_family) {
2699         case AF_LOCAL:
2700                 if (sun->sun_path[0] != '/') {
2701                         dprintk("RPC:       bad AF_LOCAL address: %s\n",
2702                                         sun->sun_path);
2703                         ret = ERR_PTR(-EINVAL);
2704                         goto out_err;
2705                 }
2706                 xprt_set_bound(xprt);
2707                 xs_format_peer_addresses(xprt, "local", RPCBIND_NETID_LOCAL);
2708                 ret = ERR_PTR(xs_local_setup_socket(transport));
2709                 if (ret)
2710                         goto out_err;
2711                 break;
2712         default:
2713                 ret = ERR_PTR(-EAFNOSUPPORT);
2714                 goto out_err;
2715         }
2716
2717         dprintk("RPC:       set up xprt to %s via AF_LOCAL\n",
2718                         xprt->address_strings[RPC_DISPLAY_ADDR]);
2719
2720         if (try_module_get(THIS_MODULE))
2721                 return xprt;
2722         ret = ERR_PTR(-EINVAL);
2723 out_err:
2724         xs_xprt_free(xprt);
2725         return ret;
2726 }
2727
2728 static const struct rpc_timeout xs_udp_default_timeout = {
2729         .to_initval = 5 * HZ,
2730         .to_maxval = 30 * HZ,
2731         .to_increment = 5 * HZ,
2732         .to_retries = 5,
2733 };
2734
2735 /**
2736  * xs_setup_udp - Set up transport to use a UDP socket
2737  * @args: rpc transport creation arguments
2738  *
2739  */
2740 static struct rpc_xprt *xs_setup_udp(struct xprt_create *args)
2741 {
2742         struct sockaddr *addr = args->dstaddr;
2743         struct rpc_xprt *xprt;
2744         struct sock_xprt *transport;
2745         struct rpc_xprt *ret;
2746
2747         xprt = xs_setup_xprt(args, xprt_udp_slot_table_entries,
2748                         xprt_udp_slot_table_entries);
2749         if (IS_ERR(xprt))
2750                 return xprt;
2751         transport = container_of(xprt, struct sock_xprt, xprt);
2752
2753         xprt->prot = IPPROTO_UDP;
2754         xprt->tsh_size = 0;
2755         /* XXX: header size can vary due to auth type, IPv6, etc. */
2756         xprt->max_payload = (1U << 16) - (MAX_HEADER << 3);
2757
2758         xprt->bind_timeout = XS_BIND_TO;
2759         xprt->reestablish_timeout = XS_UDP_REEST_TO;
2760         xprt->idle_timeout = XS_IDLE_DISC_TO;
2761
2762         xprt->ops = &xs_udp_ops;
2763
2764         xprt->timeout = &xs_udp_default_timeout;
2765
2766         switch (addr->sa_family) {
2767         case AF_INET:
2768                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2769                         xprt_set_bound(xprt);
2770
2771                 INIT_DELAYED_WORK(&transport->connect_worker,
2772                                         xs_udp_setup_socket);
2773                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP);
2774                 break;
2775         case AF_INET6:
2776                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2777                         xprt_set_bound(xprt);
2778
2779                 INIT_DELAYED_WORK(&transport->connect_worker,
2780                                         xs_udp_setup_socket);
2781                 xs_format_peer_addresses(xprt, "udp", RPCBIND_NETID_UDP6);
2782                 break;
2783         default:
2784                 ret = ERR_PTR(-EAFNOSUPPORT);
2785                 goto out_err;
2786         }
2787
2788         if (xprt_bound(xprt))
2789                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2790                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2791                                 xprt->address_strings[RPC_DISPLAY_PORT],
2792                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2793         else
2794                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2795                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2796                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2797
2798         if (try_module_get(THIS_MODULE))
2799                 return xprt;
2800         ret = ERR_PTR(-EINVAL);
2801 out_err:
2802         xs_xprt_free(xprt);
2803         return ret;
2804 }
2805
2806 static const struct rpc_timeout xs_tcp_default_timeout = {
2807         .to_initval = 60 * HZ,
2808         .to_maxval = 60 * HZ,
2809         .to_retries = 2,
2810 };
2811
2812 /**
2813  * xs_setup_tcp - Set up transport to use a TCP socket
2814  * @args: rpc transport creation arguments
2815  *
2816  */
2817 static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
2818 {
2819         struct sockaddr *addr = args->dstaddr;
2820         struct rpc_xprt *xprt;
2821         struct sock_xprt *transport;
2822         struct rpc_xprt *ret;
2823         unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
2824
2825         if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
2826                 max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
2827
2828         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2829                         max_slot_table_size);
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
2838         xprt->bind_timeout = XS_BIND_TO;
2839         xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
2840         xprt->idle_timeout = XS_IDLE_DISC_TO;
2841
2842         xprt->ops = &xs_tcp_ops;
2843         xprt->timeout = &xs_tcp_default_timeout;
2844
2845         switch (addr->sa_family) {
2846         case AF_INET:
2847                 if (((struct sockaddr_in *)addr)->sin_port != htons(0))
2848                         xprt_set_bound(xprt);
2849
2850                 INIT_DELAYED_WORK(&transport->connect_worker,
2851                                         xs_tcp_setup_socket);
2852                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP);
2853                 break;
2854         case AF_INET6:
2855                 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
2856                         xprt_set_bound(xprt);
2857
2858                 INIT_DELAYED_WORK(&transport->connect_worker,
2859                                         xs_tcp_setup_socket);
2860                 xs_format_peer_addresses(xprt, "tcp", RPCBIND_NETID_TCP6);
2861                 break;
2862         default:
2863                 ret = ERR_PTR(-EAFNOSUPPORT);
2864                 goto out_err;
2865         }
2866
2867         if (xprt_bound(xprt))
2868                 dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2869                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2870                                 xprt->address_strings[RPC_DISPLAY_PORT],
2871                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2872         else
2873                 dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
2874                                 xprt->address_strings[RPC_DISPLAY_ADDR],
2875                                 xprt->address_strings[RPC_DISPLAY_PROTO]);
2876
2877         if (try_module_get(THIS_MODULE))
2878                 return xprt;
2879         ret = ERR_PTR(-EINVAL);
2880 out_err:
2881         xs_xprt_free(xprt);
2882         return ret;
2883 }
2884
2885 /**
2886  * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
2887  * @args: rpc transport creation arguments
2888  *
2889  */
2890 static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
2891 {
2892         struct sockaddr *addr = args->dstaddr;
2893         struct rpc_xprt *xprt;
2894         struct sock_xprt *transport;
2895         struct svc_sock *bc_sock;
2896         struct rpc_xprt *ret;
2897
2898         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
2899                         xprt_tcp_slot_table_entries);
2900         if (IS_ERR(xprt))
2901                 return xprt;
2902         transport = container_of(xprt, struct sock_xprt, xprt);
2903
2904         xprt->prot = IPPROTO_TCP;
2905         xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
2906         xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
2907         xprt->timeout = &xs_tcp_default_timeout;
2908
2909         /* backchannel */
2910         xprt_set_bound(xprt);
2911         xprt->bind_timeout = 0;
2912         xprt->reestablish_timeout = 0;
2913         xprt->idle_timeout = 0;
2914
2915         xprt->ops = &bc_tcp_ops;
2916
2917         switch (addr->sa_family) {
2918         case AF_INET:
2919                 xs_format_peer_addresses(xprt, "tcp",
2920                                          RPCBIND_NETID_TCP);
2921                 break;
2922         case AF_INET6:
2923                 xs_format_peer_addresses(xprt, "tcp",
2924                                    RPCBIND_NETID_TCP6);
2925                 break;
2926         default:
2927                 ret = ERR_PTR(-EAFNOSUPPORT);
2928                 goto out_err;
2929         }
2930
2931         dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
2932                         xprt->address_strings[RPC_DISPLAY_ADDR],
2933                         xprt->address_strings[RPC_DISPLAY_PORT],
2934                         xprt->address_strings[RPC_DISPLAY_PROTO]);
2935
2936         /*
2937          * Once we've associated a backchannel xprt with a connection,
2938          * we want to keep it around as long as the connection lasts,
2939          * in case we need to start using it for a backchannel again;
2940          * this reference won't be dropped until bc_xprt is destroyed.
2941          */
2942         xprt_get(xprt);
2943         args->bc_xprt->xpt_bc_xprt = xprt;
2944         xprt->bc_xprt = args->bc_xprt;
2945         bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
2946         transport->sock = bc_sock->sk_sock;
2947         transport->inet = bc_sock->sk_sk;
2948
2949         /*
2950          * Since we don't want connections for the backchannel, we set
2951          * the xprt status to connected
2952          */
2953         xprt_set_connected(xprt);
2954
2955         if (try_module_get(THIS_MODULE))
2956                 return xprt;
2957
2958         args->bc_xprt->xpt_bc_xprt = NULL;
2959         xprt_put(xprt);
2960         ret = ERR_PTR(-EINVAL);
2961 out_err:
2962         xs_xprt_free(xprt);
2963         return ret;
2964 }
2965
2966 static struct xprt_class        xs_local_transport = {
2967         .list           = LIST_HEAD_INIT(xs_local_transport.list),
2968         .name           = "named UNIX socket",
2969         .owner          = THIS_MODULE,
2970         .ident          = XPRT_TRANSPORT_LOCAL,
2971         .setup          = xs_setup_local,
2972 };
2973
2974 static struct xprt_class        xs_udp_transport = {
2975         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
2976         .name           = "udp",
2977         .owner          = THIS_MODULE,
2978         .ident          = XPRT_TRANSPORT_UDP,
2979         .setup          = xs_setup_udp,
2980 };
2981
2982 static struct xprt_class        xs_tcp_transport = {
2983         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
2984         .name           = "tcp",
2985         .owner          = THIS_MODULE,
2986         .ident          = XPRT_TRANSPORT_TCP,
2987         .setup          = xs_setup_tcp,
2988 };
2989
2990 static struct xprt_class        xs_bc_tcp_transport = {
2991         .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
2992         .name           = "tcp NFSv4.1 backchannel",
2993         .owner          = THIS_MODULE,
2994         .ident          = XPRT_TRANSPORT_BC_TCP,
2995         .setup          = xs_setup_bc_tcp,
2996 };
2997
2998 /**
2999  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
3000  *
3001  */
3002 int init_socket_xprt(void)
3003 {
3004 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3005         if (!sunrpc_table_header)
3006                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
3007 #endif
3008
3009         xprt_register_transport(&xs_local_transport);
3010         xprt_register_transport(&xs_udp_transport);
3011         xprt_register_transport(&xs_tcp_transport);
3012         xprt_register_transport(&xs_bc_tcp_transport);
3013
3014         return 0;
3015 }
3016
3017 /**
3018  * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
3019  *
3020  */
3021 void cleanup_socket_xprt(void)
3022 {
3023 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3024         if (sunrpc_table_header) {
3025                 unregister_sysctl_table(sunrpc_table_header);
3026                 sunrpc_table_header = NULL;
3027         }
3028 #endif
3029
3030         xprt_unregister_transport(&xs_local_transport);
3031         xprt_unregister_transport(&xs_udp_transport);
3032         xprt_unregister_transport(&xs_tcp_transport);
3033         xprt_unregister_transport(&xs_bc_tcp_transport);
3034 }
3035
3036 static int param_set_uint_minmax(const char *val,
3037                 const struct kernel_param *kp,
3038                 unsigned int min, unsigned int max)
3039 {
3040         unsigned int num;
3041         int ret;
3042
3043         if (!val)
3044                 return -EINVAL;
3045         ret = kstrtouint(val, 0, &num);
3046         if (ret == -EINVAL || num < min || num > max)
3047                 return -EINVAL;
3048         *((unsigned int *)kp->arg) = num;
3049         return 0;
3050 }
3051
3052 static int param_set_portnr(const char *val, const struct kernel_param *kp)
3053 {
3054         return param_set_uint_minmax(val, kp,
3055                         RPC_MIN_RESVPORT,
3056                         RPC_MAX_RESVPORT);
3057 }
3058
3059 static const struct kernel_param_ops param_ops_portnr = {
3060         .set = param_set_portnr,
3061         .get = param_get_uint,
3062 };
3063
3064 #define param_check_portnr(name, p) \
3065         __param_check(name, p, unsigned int);
3066
3067 module_param_named(min_resvport, xprt_min_resvport, portnr, 0644);
3068 module_param_named(max_resvport, xprt_max_resvport, portnr, 0644);
3069
3070 static int param_set_slot_table_size(const char *val,
3071                                      const struct kernel_param *kp)
3072 {
3073         return param_set_uint_minmax(val, kp,
3074                         RPC_MIN_SLOT_TABLE,
3075                         RPC_MAX_SLOT_TABLE);
3076 }
3077
3078 static const struct kernel_param_ops param_ops_slot_table_size = {
3079         .set = param_set_slot_table_size,
3080         .get = param_get_uint,
3081 };
3082
3083 #define param_check_slot_table_size(name, p) \
3084         __param_check(name, p, unsigned int);
3085
3086 static int param_set_max_slot_table_size(const char *val,
3087                                      const struct kernel_param *kp)
3088 {
3089         return param_set_uint_minmax(val, kp,
3090                         RPC_MIN_SLOT_TABLE,
3091                         RPC_MAX_SLOT_TABLE_LIMIT);
3092 }
3093
3094 static const struct kernel_param_ops param_ops_max_slot_table_size = {
3095         .set = param_set_max_slot_table_size,
3096         .get = param_get_uint,
3097 };
3098
3099 #define param_check_max_slot_table_size(name, p) \
3100         __param_check(name, p, unsigned int);
3101
3102 module_param_named(tcp_slot_table_entries, xprt_tcp_slot_table_entries,
3103                    slot_table_size, 0644);
3104 module_param_named(tcp_max_slot_table_entries, xprt_max_tcp_slot_table_entries,
3105                    max_slot_table_size, 0644);
3106 module_param_named(udp_slot_table_entries, xprt_udp_slot_table_entries,
3107                    slot_table_size, 0644);
3108