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