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  * Propose an abort to be made in the I/O thread.
  22  */
  23 bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
  24                          enum rxrpc_abort_reason why)
  25 {
  26         _enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
  27
  28         if (!call->send_abort && call->state < RXRPC_CALL_COMPLETE) {
  29                 call->send_abort_why = why;
  30                 call->send_abort_err = error;
  31                 call->send_abort_seq = 0;
  32                 /* Request abort locklessly vs rxrpc_input_call_event(). */
  33                 smp_store_release(&call->send_abort, abort_code);
  34                 rxrpc_poke_call(call, rxrpc_call_poke_abort);
  35                 return true;
  36         }
  37
  38         return false;
  39 }
  40
  41 /*
  42  * Return true if there's sufficient Tx queue space.
  43  */
  44 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
  45 {
  46         if (_tx_win)
  47                 *_tx_win = call->tx_bottom;
  48         return call->tx_prepared - call->tx_bottom < 256;
  49 }
  50
  51 /*
  52  * Wait for space to appear in the Tx queue or a signal to occur.
  53  */
  54 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
  55                                          struct rxrpc_call *call,
  56                                          long *timeo)
  57 {
  58         for (;;) {
  59                 set_current_state(TASK_INTERRUPTIBLE);
  60                 if (rxrpc_check_tx_space(call, NULL))
  61                         return 0;
  62
  63                 if (call->state >= RXRPC_CALL_COMPLETE)
  64                         return call->error;
  65
  66                 if (signal_pending(current))
  67                         return sock_intr_errno(*timeo);
  68
  69                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
  70                 *timeo = schedule_timeout(*timeo);
  71         }
  72 }
  73
  74 /*
  75  * Wait for space to appear in the Tx queue uninterruptibly, but with
  76  * a timeout of 2*RTT if no progress was made and a signal occurred.
  77  */
  78 static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
  79                                             struct rxrpc_call *call)
  80 {
  81         rxrpc_seq_t tx_start, tx_win;
  82         signed long rtt, timeout;
  83
  84         rtt = READ_ONCE(call->peer->srtt_us) >> 3;
  85         rtt = usecs_to_jiffies(rtt) * 2;
  86         if (rtt < 2)
  87                 rtt = 2;
  88
  89         timeout = rtt;
  90         tx_start = smp_load_acquire(&call->acks_hard_ack);
  91
  92         for (;;) {
  93                 set_current_state(TASK_UNINTERRUPTIBLE);
  94
  95                 if (rxrpc_check_tx_space(call, &tx_win))
  96                         return 0;
  97
  98                 if (call->state >= RXRPC_CALL_COMPLETE)
  99                         return call->error;
 100
 101                 if (timeout == 0 &&
 102                     tx_win == tx_start && signal_pending(current))
 103                         return -EINTR;
 104
 105                 if (tx_win != tx_start) {
 106                         timeout = rtt;
 107                         tx_start = tx_win;
 108                 }
 109
 110                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 111                 timeout = schedule_timeout(timeout);
 112         }
 113 }
 114
 115 /*
 116  * Wait for space to appear in the Tx queue uninterruptibly.
 117  */
 118 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
 119                                             struct rxrpc_call *call,
 120                                             long *timeo)
 121 {
 122         for (;;) {
 123                 set_current_state(TASK_UNINTERRUPTIBLE);
 124                 if (rxrpc_check_tx_space(call, NULL))
 125                         return 0;
 126
 127                 if (call->state >= RXRPC_CALL_COMPLETE)
 128                         return call->error;
 129
 130                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 131                 *timeo = schedule_timeout(*timeo);
 132         }
 133 }
 134
 135 /*
 136  * wait for space to appear in the transmit/ACK window
 137  * - caller holds the socket locked
 138  */
 139 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 140                                     struct rxrpc_call *call,
 141                                     long *timeo,
 142                                     bool waitall)
 143 {
 144         DECLARE_WAITQUEUE(myself, current);
 145         int ret;
 146
 147         _enter(",{%u,%u,%u,%u}",
 148                call->tx_bottom, call->acks_hard_ack, call->tx_top, call->tx_winsize);
 149
 150         add_wait_queue(&call->waitq, &myself);
 151
 152         switch (call->interruptibility) {
 153         case RXRPC_INTERRUPTIBLE:
 154                 if (waitall)
 155                         ret = rxrpc_wait_for_tx_window_waitall(rx, call);
 156                 else
 157                         ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
 158                 break;
 159         case RXRPC_PREINTERRUPTIBLE:
 160         case RXRPC_UNINTERRUPTIBLE:
 161         default:
 162                 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
 163                 break;
 164         }
 165
 166         remove_wait_queue(&call->waitq, &myself);
 167         set_current_state(TASK_RUNNING);
 168         _leave(" = %d", ret);
 169         return ret;
 170 }
 171
 172 /*
 173  * Notify the owner of the call that the transmit phase is ended and the last
 174  * packet has been queued.
 175  */
 176 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
 177                                 rxrpc_notify_end_tx_t notify_end_tx)
 178 {
 179         if (notify_end_tx)
 180                 notify_end_tx(&rx->sk, call, call->user_call_ID);
 181 }
 182
 183 /*
 184  * Queue a DATA packet for transmission, set the resend timeout and send
 185  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
 186  * in case the caller wants to do something with it.
 187  */
 188 static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 189                                struct rxrpc_txbuf *txb,
 190                                rxrpc_notify_end_tx_t notify_end_tx)
 191 {
 192         unsigned long now;
 193         rxrpc_seq_t seq = txb->seq;
 194         bool last = test_bit(RXRPC_TXBUF_LAST, &txb->flags), poke;
 195
 196         rxrpc_inc_stat(call->rxnet, stat_tx_data);
 197
 198         ASSERTCMP(txb->seq, ==, call->tx_prepared + 1);
 199
 200         /* We have to set the timestamp before queueing as the retransmit
 201          * algorithm can see the packet as soon as we queue it.
 202          */
 203         txb->last_sent = ktime_get_real();
 204
 205         if (last)
 206                 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue_last);
 207         else
 208                 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue);
 209
 210         /* Add the packet to the call's output buffer */
 211         spin_lock(&call->tx_lock);
 212         poke = list_empty(&call->tx_sendmsg);
 213         list_add_tail(&txb->call_link, &call->tx_sendmsg);
 214         call->tx_prepared = seq;
 215         spin_unlock(&call->tx_lock);
 216
 217         if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
 218                 _debug("________awaiting reply/ACK__________");
 219                 write_lock(&call->state_lock);
 220                 switch (call->state) {
 221                 case RXRPC_CALL_CLIENT_SEND_REQUEST:
 222                         call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 223                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 224                         break;
 225                 case RXRPC_CALL_SERVER_ACK_REQUEST:
 226                         call->state = RXRPC_CALL_SERVER_SEND_REPLY;
 227                         now = jiffies;
 228                         WRITE_ONCE(call->delay_ack_at, now + MAX_JIFFY_OFFSET);
 229                         if (call->ackr_reason == RXRPC_ACK_DELAY)
 230                                 call->ackr_reason = 0;
 231                         trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
 232                         if (!last)
 233                                 break;
 234                         fallthrough;
 235                 case RXRPC_CALL_SERVER_SEND_REPLY:
 236                         call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
 237                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 238                         break;
 239                 default:
 240                         break;
 241                 }
 242                 write_unlock(&call->state_lock);
 243         }
 244
 245         if (poke)
 246                 rxrpc_poke_call(call, rxrpc_call_poke_start);
 247 }
 248
 249 /*
 250  * send data through a socket
 251  * - must be called in process context
 252  * - The caller holds the call user access mutex, but not the socket lock.
 253  */
 254 static int rxrpc_send_data(struct rxrpc_sock *rx,
 255                            struct rxrpc_call *call,
 256                            struct msghdr *msg, size_t len,
 257                            rxrpc_notify_end_tx_t notify_end_tx,
 258                            bool *_dropped_lock)
 259 {
 260         struct rxrpc_txbuf *txb;
 261         struct sock *sk = &rx->sk;
 262         enum rxrpc_call_state state;
 263         long timeo;
 264         bool more = msg->msg_flags & MSG_MORE;
 265         int ret, copied = 0;
 266
 267         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 268
 269         /* this should be in poll */
 270         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 271
 272 reload:
 273         ret = -EPIPE;
 274         if (sk->sk_shutdown & SEND_SHUTDOWN)
 275                 goto maybe_error;
 276         state = READ_ONCE(call->state);
 277         ret = -ESHUTDOWN;
 278         if (state >= RXRPC_CALL_COMPLETE)
 279                 goto maybe_error;
 280         ret = -EPROTO;
 281         if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
 282             state != RXRPC_CALL_SERVER_ACK_REQUEST &&
 283             state != RXRPC_CALL_SERVER_SEND_REPLY)
 284                 goto maybe_error;
 285
 286         ret = -EMSGSIZE;
 287         if (call->tx_total_len != -1) {
 288                 if (len - copied > call->tx_total_len)
 289                         goto maybe_error;
 290                 if (!more && len - copied != call->tx_total_len)
 291                         goto maybe_error;
 292         }
 293
 294         txb = call->tx_pending;
 295         call->tx_pending = NULL;
 296         if (txb)
 297                 rxrpc_see_txbuf(txb, rxrpc_txbuf_see_send_more);
 298
 299         do {
 300                 if (!txb) {
 301                         size_t remain, bufsize, chunk, offset;
 302
 303                         _debug("alloc");
 304
 305                         if (!rxrpc_check_tx_space(call, NULL))
 306                                 goto wait_for_space;
 307
 308                         /* Work out the maximum size of a packet.  Assume that
 309                          * the security header is going to be in the padded
 310                          * region (enc blocksize), but the trailer is not.
 311                          */
 312                         remain = more ? INT_MAX : msg_data_left(msg);
 313                         ret = call->conn->security->how_much_data(call, remain,
 314                                                                   &bufsize, &chunk, &offset);
 315                         if (ret < 0)
 316                                 goto maybe_error;
 317
 318                         _debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
 319
 320                         /* create a buffer that we can retain until it's ACK'd */
 321                         ret = -ENOMEM;
 322                         txb = rxrpc_alloc_txbuf(call, RXRPC_PACKET_TYPE_DATA,
 323                                                 GFP_KERNEL);
 324                         if (!txb)
 325                                 goto maybe_error;
 326
 327                         txb->offset = offset;
 328                         txb->space -= offset;
 329                         txb->space = min_t(size_t, chunk, txb->space);
 330                 }
 331
 332                 _debug("append");
 333
 334                 /* append next segment of data to the current buffer */
 335                 if (msg_data_left(msg) > 0) {
 336                         size_t copy = min_t(size_t, txb->space, msg_data_left(msg));
 337
 338                         _debug("add %zu", copy);
 339                         if (!copy_from_iter_full(txb->data + txb->offset, copy,
 340                                                  &msg->msg_iter))
 341                                 goto efault;
 342                         _debug("added");
 343                         txb->space -= copy;
 344                         txb->len += copy;
 345                         txb->offset += copy;
 346                         copied += copy;
 347                         if (call->tx_total_len != -1)
 348                                 call->tx_total_len -= copy;
 349                 }
 350
 351                 /* check for the far side aborting the call or a network error
 352                  * occurring */
 353                 if (call->state == RXRPC_CALL_COMPLETE)
 354                         goto call_terminated;
 355
 356                 /* add the packet to the send queue if it's now full */
 357                 if (!txb->space ||
 358                     (msg_data_left(msg) == 0 && !more)) {
 359                         if (msg_data_left(msg) == 0 && !more) {
 360                                 txb->wire.flags |= RXRPC_LAST_PACKET;
 361                                 __set_bit(RXRPC_TXBUF_LAST, &txb->flags);
 362                         }
 363                         else if (call->tx_top - call->acks_hard_ack <
 364                                  call->tx_winsize)
 365                                 txb->wire.flags |= RXRPC_MORE_PACKETS;
 366
 367                         ret = call->security->secure_packet(call, txb);
 368                         if (ret < 0)
 369                                 goto out;
 370
 371                         rxrpc_queue_packet(rx, call, txb, notify_end_tx);
 372                         txb = NULL;
 373                 }
 374         } while (msg_data_left(msg) > 0);
 375
 376 success:
 377         ret = copied;
 378         if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE) {
 379                 read_lock(&call->state_lock);
 380                 if (call->error < 0)
 381                         ret = call->error;
 382                 read_unlock(&call->state_lock);
 383         }
 384 out:
 385         call->tx_pending = txb;
 386         _leave(" = %d", ret);
 387         return ret;
 388
 389 call_terminated:
 390         rxrpc_put_txbuf(txb, rxrpc_txbuf_put_send_aborted);
 391         _leave(" = %d", call->error);
 392         return call->error;
 393
 394 maybe_error:
 395         if (copied)
 396                 goto success;
 397         goto out;
 398
 399 efault:
 400         ret = -EFAULT;
 401         goto out;
 402
 403 wait_for_space:
 404         ret = -EAGAIN;
 405         if (msg->msg_flags & MSG_DONTWAIT)
 406                 goto maybe_error;
 407         mutex_unlock(&call->user_mutex);
 408         *_dropped_lock = true;
 409         ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
 410                                        msg->msg_flags & MSG_WAITALL);
 411         if (ret < 0)
 412                 goto maybe_error;
 413         if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
 414                 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
 415                         ret = sock_intr_errno(timeo);
 416                         goto maybe_error;
 417                 }
 418         } else {
 419                 mutex_lock(&call->user_mutex);
 420         }
 421         *_dropped_lock = false;
 422         goto reload;
 423 }
 424
 425 /*
 426  * extract control messages from the sendmsg() control buffer
 427  */
 428 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
 429 {
 430         struct cmsghdr *cmsg;
 431         bool got_user_ID = false;
 432         int len;
 433
 434         if (msg->msg_controllen == 0)
 435                 return -EINVAL;
 436
 437         for_each_cmsghdr(cmsg, msg) {
 438                 if (!CMSG_OK(msg, cmsg))
 439                         return -EINVAL;
 440
 441                 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
 442                 _debug("CMSG %d, %d, %d",
 443                        cmsg->cmsg_level, cmsg->cmsg_type, len);
 444
 445                 if (cmsg->cmsg_level != SOL_RXRPC)
 446                         continue;
 447
 448                 switch (cmsg->cmsg_type) {
 449                 case RXRPC_USER_CALL_ID:
 450                         if (msg->msg_flags & MSG_CMSG_COMPAT) {
 451                                 if (len != sizeof(u32))
 452                                         return -EINVAL;
 453                                 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
 454                         } else {
 455                                 if (len != sizeof(unsigned long))
 456                                         return -EINVAL;
 457                                 p->call.user_call_ID = *(unsigned long *)
 458                                         CMSG_DATA(cmsg);
 459                         }
 460                         got_user_ID = true;
 461                         break;
 462
 463                 case RXRPC_ABORT:
 464                         if (p->command != RXRPC_CMD_SEND_DATA)
 465                                 return -EINVAL;
 466                         p->command = RXRPC_CMD_SEND_ABORT;
 467                         if (len != sizeof(p->abort_code))
 468                                 return -EINVAL;
 469                         p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
 470                         if (p->abort_code == 0)
 471                                 return -EINVAL;
 472                         break;
 473
 474                 case RXRPC_CHARGE_ACCEPT:
 475                         if (p->command != RXRPC_CMD_SEND_DATA)
 476                                 return -EINVAL;
 477                         p->command = RXRPC_CMD_CHARGE_ACCEPT;
 478                         if (len != 0)
 479                                 return -EINVAL;
 480                         break;
 481
 482                 case RXRPC_EXCLUSIVE_CALL:
 483                         p->exclusive = true;
 484                         if (len != 0)
 485                                 return -EINVAL;
 486                         break;
 487
 488                 case RXRPC_UPGRADE_SERVICE:
 489                         p->upgrade = true;
 490                         if (len != 0)
 491                                 return -EINVAL;
 492                         break;
 493
 494                 case RXRPC_TX_LENGTH:
 495                         if (p->call.tx_total_len != -1 || len != sizeof(__s64))
 496                                 return -EINVAL;
 497                         p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
 498                         if (p->call.tx_total_len < 0)
 499                                 return -EINVAL;
 500                         break;
 501
 502                 case RXRPC_SET_CALL_TIMEOUT:
 503                         if (len & 3 || len < 4 || len > 12)
 504                                 return -EINVAL;
 505                         memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
 506                         p->call.nr_timeouts = len / 4;
 507                         if (p->call.timeouts.hard > INT_MAX / HZ)
 508                                 return -ERANGE;
 509                         if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
 510                                 return -ERANGE;
 511                         if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
 512                                 return -ERANGE;
 513                         break;
 514
 515                 default:
 516                         return -EINVAL;
 517                 }
 518         }
 519
 520         if (!got_user_ID)
 521                 return -EINVAL;
 522         if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
 523                 return -EINVAL;
 524         _leave(" = 0");
 525         return 0;
 526 }
 527
 528 /*
 529  * Create a new client call for sendmsg().
 530  * - Called with the socket lock held, which it must release.
 531  * - If it returns a call, the call's lock will need releasing by the caller.
 532  */
 533 static struct rxrpc_call *
 534 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 535                                   struct rxrpc_send_params *p)
 536         __releases(&rx->sk.sk_lock.slock)
 537         __acquires(&call->user_mutex)
 538 {
 539         struct rxrpc_conn_parameters cp;
 540         struct rxrpc_call *call;
 541         struct key *key;
 542
 543         DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
 544
 545         _enter("");
 546
 547         if (!msg->msg_name) {
 548                 release_sock(&rx->sk);
 549                 return ERR_PTR(-EDESTADDRREQ);
 550         }
 551
 552         key = rx->key;
 553         if (key && !rx->key->payload.data[0])
 554                 key = NULL;
 555
 556         memset(&cp, 0, sizeof(cp));
 557         cp.local                = rx->local;
 558         cp.key                  = rx->key;
 559         cp.security_level       = rx->min_sec_level;
 560         cp.exclusive            = rx->exclusive | p->exclusive;
 561         cp.upgrade              = p->upgrade;
 562         cp.service_id           = srx->srx_service;
 563         call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
 564                                      atomic_inc_return(&rxrpc_debug_id));
 565         /* The socket is now unlocked */
 566
 567         rxrpc_put_peer(cp.peer, rxrpc_peer_put_discard_tmp);
 568         _leave(" = %p\n", call);
 569         return call;
 570 }
 571
 572 /*
 573  * send a message forming part of a client call through an RxRPC socket
 574  * - caller holds the socket locked
 575  * - the socket may be either a client socket or a server socket
 576  */
 577 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 578         __releases(&rx->sk.sk_lock.slock)
 579 {
 580         enum rxrpc_call_state state;
 581         struct rxrpc_call *call;
 582         unsigned long now, j;
 583         bool dropped_lock = false;
 584         int ret;
 585
 586         struct rxrpc_send_params p = {
 587                 .call.tx_total_len      = -1,
 588                 .call.user_call_ID      = 0,
 589                 .call.nr_timeouts       = 0,
 590                 .call.interruptibility  = RXRPC_INTERRUPTIBLE,
 591                 .abort_code             = 0,
 592                 .command                = RXRPC_CMD_SEND_DATA,
 593                 .exclusive              = false,
 594                 .upgrade                = false,
 595         };
 596
 597         _enter("");
 598
 599         ret = rxrpc_sendmsg_cmsg(msg, &p);
 600         if (ret < 0)
 601                 goto error_release_sock;
 602
 603         if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
 604                 ret = -EINVAL;
 605                 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
 606                         goto error_release_sock;
 607                 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
 608                 goto error_release_sock;
 609         }
 610
 611         call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
 612         if (!call) {
 613                 ret = -EBADSLT;
 614                 if (p.command != RXRPC_CMD_SEND_DATA)
 615                         goto error_release_sock;
 616                 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
 617                 /* The socket is now unlocked... */
 618                 if (IS_ERR(call))
 619                         return PTR_ERR(call);
 620                 /* ... and we have the call lock. */
 621                 ret = 0;
 622                 if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE)
 623                         goto out_put_unlock;
 624         } else {
 625                 switch (READ_ONCE(call->state)) {
 626                 case RXRPC_CALL_UNINITIALISED:
 627                 case RXRPC_CALL_CLIENT_AWAIT_CONN:
 628                 case RXRPC_CALL_SERVER_PREALLOC:
 629                 case RXRPC_CALL_SERVER_SECURING:
 630                         rxrpc_put_call(call, rxrpc_call_put_sendmsg);
 631                         ret = -EBUSY;
 632                         goto error_release_sock;
 633                 default:
 634                         break;
 635                 }
 636
 637                 ret = mutex_lock_interruptible(&call->user_mutex);
 638                 release_sock(&rx->sk);
 639                 if (ret < 0) {
 640                         ret = -ERESTARTSYS;
 641                         goto error_put;
 642                 }
 643
 644                 if (p.call.tx_total_len != -1) {
 645                         ret = -EINVAL;
 646                         if (call->tx_total_len != -1 ||
 647                             call->tx_pending ||
 648                             call->tx_top != 0)
 649                                 goto out_put_unlock;
 650                         call->tx_total_len = p.call.tx_total_len;
 651                 }
 652         }
 653
 654         switch (p.call.nr_timeouts) {
 655         case 3:
 656                 j = msecs_to_jiffies(p.call.timeouts.normal);
 657                 if (p.call.timeouts.normal > 0 && j == 0)
 658                         j = 1;
 659                 WRITE_ONCE(call->next_rx_timo, j);
 660                 fallthrough;
 661         case 2:
 662                 j = msecs_to_jiffies(p.call.timeouts.idle);
 663                 if (p.call.timeouts.idle > 0 && j == 0)
 664                         j = 1;
 665                 WRITE_ONCE(call->next_req_timo, j);
 666                 fallthrough;
 667         case 1:
 668                 if (p.call.timeouts.hard > 0) {
 669                         j = msecs_to_jiffies(p.call.timeouts.hard);
 670                         now = jiffies;
 671                         j += now;
 672                         WRITE_ONCE(call->expect_term_by, j);
 673                         rxrpc_reduce_call_timer(call, j, now,
 674                                                 rxrpc_timer_set_for_hard);
 675                 }
 676                 break;
 677         }
 678
 679         state = READ_ONCE(call->state);
 680         _debug("CALL %d USR %lx ST %d on CONN %p",
 681                call->debug_id, call->user_call_ID, state, call->conn);
 682
 683         if (state >= RXRPC_CALL_COMPLETE) {
 684                 /* it's too late for this call */
 685                 ret = -ESHUTDOWN;
 686         } else if (p.command == RXRPC_CMD_SEND_ABORT) {
 687                 rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED,
 688                                     rxrpc_abort_call_sendmsg);
 689                 ret = 0;
 690         } else if (p.command != RXRPC_CMD_SEND_DATA) {
 691                 ret = -EINVAL;
 692         } else {
 693                 ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
 694         }
 695
 696 out_put_unlock:
 697         if (!dropped_lock)
 698                 mutex_unlock(&call->user_mutex);
 699 error_put:
 700         rxrpc_put_call(call, rxrpc_call_put_sendmsg);
 701         _leave(" = %d", ret);
 702         return ret;
 703
 704 error_release_sock:
 705         release_sock(&rx->sk);
 706         return ret;
 707 }
 708
 709 /**
 710  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
 711  * @sock: The socket the call is on
 712  * @call: The call to send data through
 713  * @msg: The data to send
 714  * @len: The amount of data to send
 715  * @notify_end_tx: Notification that the last packet is queued.
 716  *
 717  * Allow a kernel service to send data on a call.  The call must be in an state
 718  * appropriate to sending data.  No control data should be supplied in @msg,
 719  * nor should an address be supplied.  MSG_MORE should be flagged if there's
 720  * more data to come, otherwise this data will end the transmission phase.
 721  */
 722 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 723                            struct msghdr *msg, size_t len,
 724                            rxrpc_notify_end_tx_t notify_end_tx)
 725 {
 726         bool dropped_lock = false;
 727         int ret;
 728
 729         _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
 730
 731         ASSERTCMP(msg->msg_name, ==, NULL);
 732         ASSERTCMP(msg->msg_control, ==, NULL);
 733
 734         mutex_lock(&call->user_mutex);
 735
 736         _debug("CALL %d USR %lx ST %d on CONN %p",
 737                call->debug_id, call->user_call_ID, call->state, call->conn);
 738
 739         switch (READ_ONCE(call->state)) {
 740         case RXRPC_CALL_CLIENT_SEND_REQUEST:
 741         case RXRPC_CALL_SERVER_ACK_REQUEST:
 742         case RXRPC_CALL_SERVER_SEND_REPLY:
 743                 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
 744                                       notify_end_tx, &dropped_lock);
 745                 break;
 746         case RXRPC_CALL_COMPLETE:
 747                 read_lock(&call->state_lock);
 748                 ret = call->error;
 749                 read_unlock(&call->state_lock);
 750                 break;
 751         default:
 752                 /* Request phase complete for this client call */
 753                 trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send,
 754                                   call->cid, call->call_id, call->rx_consumed,
 755                                   0, -EPROTO);
 756                 ret = -EPROTO;
 757                 break;
 758         }
 759
 760         if (!dropped_lock)
 761                 mutex_unlock(&call->user_mutex);
 762         _leave(" = %d", ret);
 763         return ret;
 764 }
 765 EXPORT_SYMBOL(rxrpc_kernel_send_data);
 766
 767 /**
 768  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
 769  * @sock: The socket the call is on
 770  * @call: The call to be aborted
 771  * @abort_code: The abort code to stick into the ABORT packet
 772  * @error: Local error value
 773  * @why: Indication as to why.
 774  *
 775  * Allow a kernel service to abort a call, if it's still in an abortable state
 776  * and return true if the call was aborted, false if it was already complete.
 777  */
 778 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 779                              u32 abort_code, int error, enum rxrpc_abort_reason why)
 780 {
 781         bool aborted;
 782
 783         _enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
 784
 785         mutex_lock(&call->user_mutex);
 786         aborted = rxrpc_propose_abort(call, abort_code, error, why);
 787         mutex_unlock(&call->user_mutex);
 788         return aborted;
 789 }
 790 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
 791
 792 /**
 793  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
 794  * @sock: The socket the call is on
 795  * @call: The call to be informed
 796  * @tx_total_len: The amount of data to be transmitted for this call
 797  *
 798  * Allow a kernel service to set the total transmit length on a call.  This
 799  * allows buffer-to-packet encrypt-and-copy to be performed.
 800  *
 801  * This function is primarily for use for setting the reply length since the
 802  * request length can be set when beginning the call.
 803  */
 804 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
 805                                 s64 tx_total_len)
 806 {
 807         WARN_ON(call->tx_total_len != -1);
 808         call->tx_total_len = tx_total_len;
 809 }
 810 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);