net/rxrpc/sendmsg.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* AF_RXRPC sendmsg() implementation.
   3  *
   4  * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
   5  * Written by David Howells (dhowells@redhat.com)
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/net.h>
  11 #include <linux/gfp.h>
  12 #include <linux/skbuff.h>
  13 #include <linux/export.h>
  14 #include <linux/sched/signal.h>
  15
  16 #include <net/sock.h>
  17 #include <net/af_rxrpc.h>
  18 #include "ar-internal.h"
  19
  20 /*
  21  * Wait for space to appear in the Tx queue or a signal to occur.
  22  */
  23 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
  24                                          struct rxrpc_call *call,
  25                                          long *timeo)
  26 {
  27         for (;;) {
  28                 set_current_state(TASK_INTERRUPTIBLE);
  29                 if (call->tx_top - call->tx_hard_ack <
  30                     min_t(unsigned int, call->tx_winsize,
  31                           call->cong_cwnd + call->cong_extra))
  32                         return 0;
  33
  34                 if (call->state >= RXRPC_CALL_COMPLETE)
  35                         return call->error;
  36
  37                 if (signal_pending(current))
  38                         return sock_intr_errno(*timeo);
  39
  40                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
  41                 mutex_unlock(&call->user_mutex);
  42                 *timeo = schedule_timeout(*timeo);
  43                 if (mutex_lock_interruptible(&call->user_mutex) < 0)
  44                         return sock_intr_errno(*timeo);
  45         }
  46 }
  47
  48 /*
  49  * Wait for space to appear in the Tx queue uninterruptibly, but with
  50  * a timeout of 2*RTT if no progress was made and a signal occurred.
  51  */
  52 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
  53                                             struct rxrpc_call *call)
  54 {
  55         rxrpc_seq_t tx_start, tx_win;
  56         signed long rtt2, timeout;
  57         u64 rtt;
  58
  59         rtt = READ_ONCE(call->peer->rtt);
  60         rtt2 = nsecs_to_jiffies64(rtt) * 2;
  61         if (rtt2 < 1)
  62                 rtt2 = 1;
  63
  64         timeout = rtt2;
  65         tx_start = READ_ONCE(call->tx_hard_ack);
  66
  67         for (;;) {
  68                 set_current_state(TASK_UNINTERRUPTIBLE);
  69
  70                 tx_win = READ_ONCE(call->tx_hard_ack);
  71                 if (call->tx_top - tx_win <
  72                     min_t(unsigned int, call->tx_winsize,
  73                           call->cong_cwnd + call->cong_extra))
  74                         return 0;
  75
  76                 if (call->state >= RXRPC_CALL_COMPLETE)
  77                         return call->error;
  78
  79                 if (test_bit(RXRPC_CALL_IS_INTR, &call->flags) &&
  80                     timeout == 0 &&
  81                     tx_win == tx_start && signal_pending(current))
  82                         return -EINTR;
  83
  84                 if (tx_win != tx_start) {
  85                         timeout = rtt2;
  86                         tx_start = tx_win;
  87                 }
  88
  89                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
  90                 timeout = schedule_timeout(timeout);
  91         }
  92 }
  93
  94 /*
  95  * wait for space to appear in the transmit/ACK window
  96  * - caller holds the socket locked
  97  */
  98 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
  99                                     struct rxrpc_call *call,
 100                                     long *timeo,
 101                                     bool waitall)
 102 {
 103         DECLARE_WAITQUEUE(myself, current);
 104         int ret;
 105
 106         _enter(",{%u,%u,%u}",
 107                call->tx_hard_ack, call->tx_top, call->tx_winsize);
 108
 109         add_wait_queue(&call->waitq, &myself);
 110
 111         if (waitall)
 112                 ret = rxrpc_wait_for_tx_window_nonintr(rx, call);
 113         else
 114                 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
 115
 116         remove_wait_queue(&call->waitq, &myself);
 117         set_current_state(TASK_RUNNING);
 118         _leave(" = %d", ret);
 119         return ret;
 120 }
 121
 122 /*
 123  * Schedule an instant Tx resend.
 124  */
 125 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
 126 {
 127         spin_lock_bh(&call->lock);
 128
 129         if (call->state < RXRPC_CALL_COMPLETE) {
 130                 call->rxtx_annotations[ix] =
 131                         (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
 132                         RXRPC_TX_ANNO_RETRANS;
 133                 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 134                         rxrpc_queue_call(call);
 135         }
 136
 137         spin_unlock_bh(&call->lock);
 138 }
 139
 140 /*
 141  * Notify the owner of the call that the transmit phase is ended and the last
 142  * packet has been queued.
 143  */
 144 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
 145                                 rxrpc_notify_end_tx_t notify_end_tx)
 146 {
 147         if (notify_end_tx)
 148                 notify_end_tx(&rx->sk, call, call->user_call_ID);
 149 }
 150
 151 /*
 152  * Queue a DATA packet for transmission, set the resend timeout and send
 153  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
 154  * in case the caller wants to do something with it.
 155  */
 156 static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 157                               struct sk_buff *skb, bool last,
 158                               rxrpc_notify_end_tx_t notify_end_tx)
 159 {
 160         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 161         unsigned long now;
 162         rxrpc_seq_t seq = sp->hdr.seq;
 163         int ret, ix;
 164         u8 annotation = RXRPC_TX_ANNO_UNACK;
 165
 166         _net("queue skb %p [%d]", skb, seq);
 167
 168         ASSERTCMP(seq, ==, call->tx_top + 1);
 169
 170         if (last)
 171                 annotation |= RXRPC_TX_ANNO_LAST;
 172
 173         /* We have to set the timestamp before queueing as the retransmit
 174          * algorithm can see the packet as soon as we queue it.
 175          */
 176         skb->tstamp = ktime_get_real();
 177
 178         ix = seq & RXRPC_RXTX_BUFF_MASK;
 179         rxrpc_get_skb(skb, rxrpc_skb_tx_got);
 180         call->rxtx_annotations[ix] = annotation;
 181         smp_wmb();
 182         call->rxtx_buffer[ix] = skb;
 183         call->tx_top = seq;
 184         if (last)
 185                 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
 186         else
 187                 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
 188
 189         if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
 190                 _debug("________awaiting reply/ACK__________");
 191                 write_lock_bh(&call->state_lock);
 192                 switch (call->state) {
 193                 case RXRPC_CALL_CLIENT_SEND_REQUEST:
 194                         call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 195                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 196                         break;
 197                 case RXRPC_CALL_SERVER_ACK_REQUEST:
 198                         call->state = RXRPC_CALL_SERVER_SEND_REPLY;
 199                         now = jiffies;
 200                         WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
 201                         if (call->ackr_reason == RXRPC_ACK_DELAY)
 202                                 call->ackr_reason = 0;
 203                         trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
 204                         if (!last)
 205                                 break;
 206                         /* Fall through */
 207                 case RXRPC_CALL_SERVER_SEND_REPLY:
 208                         call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
 209                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 210                         break;
 211                 default:
 212                         break;
 213                 }
 214                 write_unlock_bh(&call->state_lock);
 215         }
 216
 217         if (seq == 1 && rxrpc_is_client_call(call))
 218                 rxrpc_expose_client_call(call);
 219
 220         ret = rxrpc_send_data_packet(call, skb, false);
 221         if (ret < 0) {
 222                 switch (ret) {
 223                 case -ENETUNREACH:
 224                 case -EHOSTUNREACH:
 225                 case -ECONNREFUSED:
 226                         rxrpc_set_call_completion(call,
 227                                                   RXRPC_CALL_LOCAL_ERROR,
 228                                                   0, ret);
 229                         rxrpc_notify_socket(call);
 230                         goto out;
 231                 }
 232                 _debug("need instant resend %d", ret);
 233                 rxrpc_instant_resend(call, ix);
 234         } else {
 235                 unsigned long now = jiffies, resend_at;
 236
 237                 if (call->peer->rtt_usage > 1)
 238                         resend_at = nsecs_to_jiffies(call->peer->rtt * 3 / 2);
 239                 else
 240                         resend_at = rxrpc_resend_timeout;
 241                 if (resend_at < 1)
 242                         resend_at = 1;
 243
 244                 resend_at += now;
 245                 WRITE_ONCE(call->resend_at, resend_at);
 246                 rxrpc_reduce_call_timer(call, resend_at, now,
 247                                         rxrpc_timer_set_for_send);
 248         }
 249
 250 out:
 251         rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
 252         _leave(" = %d", ret);
 253         return ret;
 254 }
 255
 256 /*
 257  * send data through a socket
 258  * - must be called in process context
 259  * - The caller holds the call user access mutex, but not the socket lock.
 260  */
 261 static int rxrpc_send_data(struct rxrpc_sock *rx,
 262                            struct rxrpc_call *call,
 263                            struct msghdr *msg, size_t len,
 264                            rxrpc_notify_end_tx_t notify_end_tx)
 265 {
 266         struct rxrpc_skb_priv *sp;
 267         struct sk_buff *skb;
 268         struct sock *sk = &rx->sk;
 269         long timeo;
 270         bool more;
 271         int ret, copied;
 272
 273         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 274
 275         /* this should be in poll */
 276         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 277
 278         if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
 279                 return -EPIPE;
 280
 281         more = msg->msg_flags & MSG_MORE;
 282
 283         if (call->tx_total_len != -1) {
 284                 if (len > call->tx_total_len)
 285                         return -EMSGSIZE;
 286                 if (!more && len != call->tx_total_len)
 287                         return -EMSGSIZE;
 288         }
 289
 290         skb = call->tx_pending;
 291         call->tx_pending = NULL;
 292         rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
 293
 294         copied = 0;
 295         do {
 296                 /* Check to see if there's a ping ACK to reply to. */
 297                 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
 298                         rxrpc_send_ack_packet(call, false, NULL);
 299
 300                 if (!skb) {
 301                         size_t size, chunk, max, space;
 302
 303                         _debug("alloc");
 304
 305                         if (call->tx_top - call->tx_hard_ack >=
 306                             min_t(unsigned int, call->tx_winsize,
 307                                   call->cong_cwnd + call->cong_extra)) {
 308                                 ret = -EAGAIN;
 309                                 if (msg->msg_flags & MSG_DONTWAIT)
 310                                         goto maybe_error;
 311                                 ret = rxrpc_wait_for_tx_window(rx, call,
 312                                                                &timeo,
 313                                                                msg->msg_flags & MSG_WAITALL);
 314                                 if (ret < 0)
 315                                         goto maybe_error;
 316                         }
 317
 318                         max = RXRPC_JUMBO_DATALEN;
 319                         max -= call->conn->security_size;
 320                         max &= ~(call->conn->size_align - 1UL);
 321
 322                         chunk = max;
 323                         if (chunk > msg_data_left(msg) && !more)
 324                                 chunk = msg_data_left(msg);
 325
 326                         space = chunk + call->conn->size_align;
 327                         space &= ~(call->conn->size_align - 1UL);
 328
 329                         size = space + call->conn->security_size;
 330
 331                         _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
 332
 333                         /* create a buffer that we can retain until it's ACK'd */
 334                         skb = sock_alloc_send_skb(
 335                                 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
 336                         if (!skb)
 337                                 goto maybe_error;
 338
 339                         rxrpc_new_skb(skb, rxrpc_skb_tx_new);
 340
 341                         _debug("ALLOC SEND %p", skb);
 342
 343                         ASSERTCMP(skb->mark, ==, 0);
 344
 345                         _debug("HS: %u", call->conn->security_size);
 346                         skb_reserve(skb, call->conn->security_size);
 347                         skb->len += call->conn->security_size;
 348
 349                         sp = rxrpc_skb(skb);
 350                         sp->remain = chunk;
 351                         if (sp->remain > skb_tailroom(skb))
 352                                 sp->remain = skb_tailroom(skb);
 353
 354                         _net("skb: hr %d, tr %d, hl %d, rm %d",
 355                                skb_headroom(skb),
 356                                skb_tailroom(skb),
 357                                skb_headlen(skb),
 358                                sp->remain);
 359
 360                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 361                 }
 362
 363                 _debug("append");
 364                 sp = rxrpc_skb(skb);
 365
 366                 /* append next segment of data to the current buffer */
 367                 if (msg_data_left(msg) > 0) {
 368                         int copy = skb_tailroom(skb);
 369                         ASSERTCMP(copy, >, 0);
 370                         if (copy > msg_data_left(msg))
 371                                 copy = msg_data_left(msg);
 372                         if (copy > sp->remain)
 373                                 copy = sp->remain;
 374
 375                         _debug("add");
 376                         ret = skb_add_data(skb, &msg->msg_iter, copy);
 377                         _debug("added");
 378                         if (ret < 0)
 379                                 goto efault;
 380                         sp->remain -= copy;
 381                         skb->mark += copy;
 382                         copied += copy;
 383                         if (call->tx_total_len != -1)
 384                                 call->tx_total_len -= copy;
 385                 }
 386
 387                 /* check for the far side aborting the call or a network error
 388                  * occurring */
 389                 if (call->state == RXRPC_CALL_COMPLETE)
 390                         goto call_terminated;
 391
 392                 /* add the packet to the send queue if it's now full */
 393                 if (sp->remain <= 0 ||
 394                     (msg_data_left(msg) == 0 && !more)) {
 395                         struct rxrpc_connection *conn = call->conn;
 396                         uint32_t seq;
 397                         size_t pad;
 398
 399                         /* pad out if we're using security */
 400                         if (conn->security_ix) {
 401                                 pad = conn->security_size + skb->mark;
 402                                 pad = conn->size_align - pad;
 403                                 pad &= conn->size_align - 1;
 404                                 _debug("pad %zu", pad);
 405                                 if (pad)
 406                                         skb_put_zero(skb, pad);
 407                         }
 408
 409                         seq = call->tx_top + 1;
 410
 411                         sp->hdr.seq     = seq;
 412                         sp->hdr._rsvd   = 0;
 413                         sp->hdr.flags   = conn->out_clientflag;
 414
 415                         if (msg_data_left(msg) == 0 && !more)
 416                                 sp->hdr.flags |= RXRPC_LAST_PACKET;
 417                         else if (call->tx_top - call->tx_hard_ack <
 418                                  call->tx_winsize)
 419                                 sp->hdr.flags |= RXRPC_MORE_PACKETS;
 420
 421                         ret = conn->security->secure_packet(
 422                                 call, skb, skb->mark, skb->head);
 423                         if (ret < 0)
 424                                 goto out;
 425
 426                         ret = rxrpc_queue_packet(rx, call, skb,
 427                                                  !msg_data_left(msg) && !more,
 428                                                  notify_end_tx);
 429                         /* Should check for failure here */
 430                         skb = NULL;
 431                 }
 432         } while (msg_data_left(msg) > 0);
 433
 434 success:
 435         ret = copied;
 436 out:
 437         call->tx_pending = skb;
 438         _leave(" = %d", ret);
 439         return ret;
 440
 441 call_terminated:
 442         rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
 443         _leave(" = %d", call->error);
 444         return call->error;
 445
 446 maybe_error:
 447         if (copied)
 448                 goto success;
 449         goto out;
 450
 451 efault:
 452         ret = -EFAULT;
 453         goto out;
 454 }
 455
 456 /*
 457  * extract control messages from the sendmsg() control buffer
 458  */
 459 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
 460 {
 461         struct cmsghdr *cmsg;
 462         bool got_user_ID = false;
 463         int len;
 464
 465         if (msg->msg_controllen == 0)
 466                 return -EINVAL;
 467
 468         for_each_cmsghdr(cmsg, msg) {
 469                 if (!CMSG_OK(msg, cmsg))
 470                         return -EINVAL;
 471
 472                 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
 473                 _debug("CMSG %d, %d, %d",
 474                        cmsg->cmsg_level, cmsg->cmsg_type, len);
 475
 476                 if (cmsg->cmsg_level != SOL_RXRPC)
 477                         continue;
 478
 479                 switch (cmsg->cmsg_type) {
 480                 case RXRPC_USER_CALL_ID:
 481                         if (msg->msg_flags & MSG_CMSG_COMPAT) {
 482                                 if (len != sizeof(u32))
 483                                         return -EINVAL;
 484                                 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
 485                         } else {
 486                                 if (len != sizeof(unsigned long))
 487                                         return -EINVAL;
 488                                 p->call.user_call_ID = *(unsigned long *)
 489                                         CMSG_DATA(cmsg);
 490                         }
 491                         got_user_ID = true;
 492                         break;
 493
 494                 case RXRPC_ABORT:
 495                         if (p->command != RXRPC_CMD_SEND_DATA)
 496                                 return -EINVAL;
 497                         p->command = RXRPC_CMD_SEND_ABORT;
 498                         if (len != sizeof(p->abort_code))
 499                                 return -EINVAL;
 500                         p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
 501                         if (p->abort_code == 0)
 502                                 return -EINVAL;
 503                         break;
 504
 505                 case RXRPC_ACCEPT:
 506                         if (p->command != RXRPC_CMD_SEND_DATA)
 507                                 return -EINVAL;
 508                         p->command = RXRPC_CMD_ACCEPT;
 509                         if (len != 0)
 510                                 return -EINVAL;
 511                         break;
 512
 513                 case RXRPC_EXCLUSIVE_CALL:
 514                         p->exclusive = true;
 515                         if (len != 0)
 516                                 return -EINVAL;
 517                         break;
 518
 519                 case RXRPC_UPGRADE_SERVICE:
 520                         p->upgrade = true;
 521                         if (len != 0)
 522                                 return -EINVAL;
 523                         break;
 524
 525                 case RXRPC_TX_LENGTH:
 526                         if (p->call.tx_total_len != -1 || len != sizeof(__s64))
 527                                 return -EINVAL;
 528                         p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
 529                         if (p->call.tx_total_len < 0)
 530                                 return -EINVAL;
 531                         break;
 532
 533                 case RXRPC_SET_CALL_TIMEOUT:
 534                         if (len & 3 || len < 4 || len > 12)
 535                                 return -EINVAL;
 536                         memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
 537                         p->call.nr_timeouts = len / 4;
 538                         if (p->call.timeouts.hard > INT_MAX / HZ)
 539                                 return -ERANGE;
 540                         if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
 541                                 return -ERANGE;
 542                         if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
 543                                 return -ERANGE;
 544                         break;
 545
 546                 default:
 547                         return -EINVAL;
 548                 }
 549         }
 550
 551         if (!got_user_ID)
 552                 return -EINVAL;
 553         if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
 554                 return -EINVAL;
 555         _leave(" = 0");
 556         return 0;
 557 }
 558
 559 /*
 560  * Create a new client call for sendmsg().
 561  * - Called with the socket lock held, which it must release.
 562  * - If it returns a call, the call's lock will need releasing by the caller.
 563  */
 564 static struct rxrpc_call *
 565 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 566                                   struct rxrpc_send_params *p)
 567         __releases(&rx->sk.sk_lock.slock)
 568         __acquires(&call->user_mutex)
 569 {
 570         struct rxrpc_conn_parameters cp;
 571         struct rxrpc_call *call;
 572         struct key *key;
 573
 574         DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
 575
 576         _enter("");
 577
 578         if (!msg->msg_name) {
 579                 release_sock(&rx->sk);
 580                 return ERR_PTR(-EDESTADDRREQ);
 581         }
 582
 583         key = rx->key;
 584         if (key && !rx->key->payload.data[0])
 585                 key = NULL;
 586
 587         memset(&cp, 0, sizeof(cp));
 588         cp.local                = rx->local;
 589         cp.key                  = rx->key;
 590         cp.security_level       = rx->min_sec_level;
 591         cp.exclusive            = rx->exclusive | p->exclusive;
 592         cp.upgrade              = p->upgrade;
 593         cp.service_id           = srx->srx_service;
 594         call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
 595                                      atomic_inc_return(&rxrpc_debug_id));
 596         /* The socket is now unlocked */
 597
 598         rxrpc_put_peer(cp.peer);
 599         _leave(" = %p\n", call);
 600         return call;
 601 }
 602
 603 /*
 604  * send a message forming part of a client call through an RxRPC socket
 605  * - caller holds the socket locked
 606  * - the socket may be either a client socket or a server socket
 607  */
 608 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 609         __releases(&rx->sk.sk_lock.slock)
 610         __releases(&call->user_mutex)
 611 {
 612         enum rxrpc_call_state state;
 613         struct rxrpc_call *call;
 614         unsigned long now, j;
 615         int ret;
 616
 617         struct rxrpc_send_params p = {
 618                 .call.tx_total_len      = -1,
 619                 .call.user_call_ID      = 0,
 620                 .call.nr_timeouts       = 0,
 621                 .call.intr              = true,
 622                 .abort_code             = 0,
 623                 .command                = RXRPC_CMD_SEND_DATA,
 624                 .exclusive              = false,
 625                 .upgrade                = false,
 626         };
 627
 628         _enter("");
 629
 630         ret = rxrpc_sendmsg_cmsg(msg, &p);
 631         if (ret < 0)
 632                 goto error_release_sock;
 633
 634         if (p.command == RXRPC_CMD_ACCEPT) {
 635                 ret = -EINVAL;
 636                 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
 637                         goto error_release_sock;
 638                 call = rxrpc_accept_call(rx, p.call.user_call_ID, NULL);
 639                 /* The socket is now unlocked. */
 640                 if (IS_ERR(call))
 641                         return PTR_ERR(call);
 642                 ret = 0;
 643                 goto out_put_unlock;
 644         }
 645
 646         call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
 647         if (!call) {
 648                 ret = -EBADSLT;
 649                 if (p.command != RXRPC_CMD_SEND_DATA)
 650                         goto error_release_sock;
 651                 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
 652                 /* The socket is now unlocked... */
 653                 if (IS_ERR(call))
 654                         return PTR_ERR(call);
 655                 /* ... and we have the call lock. */
 656         } else {
 657                 switch (READ_ONCE(call->state)) {
 658                 case RXRPC_CALL_UNINITIALISED:
 659                 case RXRPC_CALL_CLIENT_AWAIT_CONN:
 660                 case RXRPC_CALL_SERVER_PREALLOC:
 661                 case RXRPC_CALL_SERVER_SECURING:
 662                 case RXRPC_CALL_SERVER_ACCEPTING:
 663                         ret = -EBUSY;
 664                         goto error_release_sock;
 665                 default:
 666                         break;
 667                 }
 668
 669                 ret = mutex_lock_interruptible(&call->user_mutex);
 670                 release_sock(&rx->sk);
 671                 if (ret < 0) {
 672                         ret = -ERESTARTSYS;
 673                         goto error_put;
 674                 }
 675
 676                 if (p.call.tx_total_len != -1) {
 677                         ret = -EINVAL;
 678                         if (call->tx_total_len != -1 ||
 679                             call->tx_pending ||
 680                             call->tx_top != 0)
 681                                 goto error_put;
 682                         call->tx_total_len = p.call.tx_total_len;
 683                 }
 684         }
 685
 686         switch (p.call.nr_timeouts) {
 687         case 3:
 688                 j = msecs_to_jiffies(p.call.timeouts.normal);
 689                 if (p.call.timeouts.normal > 0 && j == 0)
 690                         j = 1;
 691                 WRITE_ONCE(call->next_rx_timo, j);
 692                 /* Fall through */
 693         case 2:
 694                 j = msecs_to_jiffies(p.call.timeouts.idle);
 695                 if (p.call.timeouts.idle > 0 && j == 0)
 696                         j = 1;
 697                 WRITE_ONCE(call->next_req_timo, j);
 698                 /* Fall through */
 699         case 1:
 700                 if (p.call.timeouts.hard > 0) {
 701                         j = msecs_to_jiffies(p.call.timeouts.hard);
 702                         now = jiffies;
 703                         j += now;
 704                         WRITE_ONCE(call->expect_term_by, j);
 705                         rxrpc_reduce_call_timer(call, j, now,
 706                                                 rxrpc_timer_set_for_hard);
 707                 }
 708                 break;
 709         }
 710
 711         state = READ_ONCE(call->state);
 712         _debug("CALL %d USR %lx ST %d on CONN %p",
 713                call->debug_id, call->user_call_ID, state, call->conn);
 714
 715         if (state >= RXRPC_CALL_COMPLETE) {
 716                 /* it's too late for this call */
 717                 ret = -ESHUTDOWN;
 718         } else if (p.command == RXRPC_CMD_SEND_ABORT) {
 719                 ret = 0;
 720                 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
 721                         ret = rxrpc_send_abort_packet(call);
 722         } else if (p.command != RXRPC_CMD_SEND_DATA) {
 723                 ret = -EINVAL;
 724         } else if (rxrpc_is_client_call(call) &&
 725                    state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
 726                 /* request phase complete for this client call */
 727                 ret = -EPROTO;
 728         } else if (rxrpc_is_service_call(call) &&
 729                    state != RXRPC_CALL_SERVER_ACK_REQUEST &&
 730                    state != RXRPC_CALL_SERVER_SEND_REPLY) {
 731                 /* Reply phase not begun or not complete for service call. */
 732                 ret = -EPROTO;
 733         } else {
 734                 ret = rxrpc_send_data(rx, call, msg, len, NULL);
 735         }
 736
 737 out_put_unlock:
 738         mutex_unlock(&call->user_mutex);
 739 error_put:
 740         rxrpc_put_call(call, rxrpc_call_put);
 741         _leave(" = %d", ret);
 742         return ret;
 743
 744 error_release_sock:
 745         release_sock(&rx->sk);
 746         return ret;
 747 }
 748
 749 /**
 750  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
 751  * @sock: The socket the call is on
 752  * @call: The call to send data through
 753  * @msg: The data to send
 754  * @len: The amount of data to send
 755  * @notify_end_tx: Notification that the last packet is queued.
 756  *
 757  * Allow a kernel service to send data on a call.  The call must be in an state
 758  * appropriate to sending data.  No control data should be supplied in @msg,
 759  * nor should an address be supplied.  MSG_MORE should be flagged if there's
 760  * more data to come, otherwise this data will end the transmission phase.
 761  */
 762 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 763                            struct msghdr *msg, size_t len,
 764                            rxrpc_notify_end_tx_t notify_end_tx)
 765 {
 766         int ret;
 767
 768         _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
 769
 770         ASSERTCMP(msg->msg_name, ==, NULL);
 771         ASSERTCMP(msg->msg_control, ==, NULL);
 772
 773         mutex_lock(&call->user_mutex);
 774
 775         _debug("CALL %d USR %lx ST %d on CONN %p",
 776                call->debug_id, call->user_call_ID, call->state, call->conn);
 777
 778         switch (READ_ONCE(call->state)) {
 779         case RXRPC_CALL_CLIENT_SEND_REQUEST:
 780         case RXRPC_CALL_SERVER_ACK_REQUEST:
 781         case RXRPC_CALL_SERVER_SEND_REPLY:
 782                 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
 783                                       notify_end_tx);
 784                 break;
 785         case RXRPC_CALL_COMPLETE:
 786                 read_lock_bh(&call->state_lock);
 787                 ret = call->error;
 788                 read_unlock_bh(&call->state_lock);
 789                 break;
 790         default:
 791                 /* Request phase complete for this client call */
 792                 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
 793                 ret = -EPROTO;
 794                 break;
 795         }
 796
 797         mutex_unlock(&call->user_mutex);
 798         _leave(" = %d", ret);
 799         return ret;
 800 }
 801 EXPORT_SYMBOL(rxrpc_kernel_send_data);
 802
 803 /**
 804  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
 805  * @sock: The socket the call is on
 806  * @call: The call to be aborted
 807  * @abort_code: The abort code to stick into the ABORT packet
 808  * @error: Local error value
 809  * @why: 3-char string indicating why.
 810  *
 811  * Allow a kernel service to abort a call, if it's still in an abortable state
 812  * and return true if the call was aborted, false if it was already complete.
 813  */
 814 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 815                              u32 abort_code, int error, const char *why)
 816 {
 817         bool aborted;
 818
 819         _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
 820
 821         mutex_lock(&call->user_mutex);
 822
 823         aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
 824         if (aborted)
 825                 rxrpc_send_abort_packet(call);
 826
 827         mutex_unlock(&call->user_mutex);
 828         return aborted;
 829 }
 830 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
 831
 832 /**
 833  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
 834  * @sock: The socket the call is on
 835  * @call: The call to be informed
 836  * @tx_total_len: The amount of data to be transmitted for this call
 837  *
 838  * Allow a kernel service to set the total transmit length on a call.  This
 839  * allows buffer-to-packet encrypt-and-copy to be performed.
 840  *
 841  * This function is primarily for use for setting the reply length since the
 842  * request length can be set when beginning the call.
 843  */
 844 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
 845                                 s64 tx_total_len)
 846 {
 847         WARN_ON(call->tx_total_len != -1);
 848         call->tx_total_len = tx_total_len;
 849 }
 850 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);