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 && !rxrpc_call_is_complete(call)) {
  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  * Wait for a call to become connected.  Interruption here doesn't cause the
  43  * call to be aborted.
  44  */
  45 static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
  46 {
  47         DECLARE_WAITQUEUE(myself, current);
  48         int ret = 0;
  49
  50         _enter("%d", call->debug_id);
  51
  52         if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
  53                 goto no_wait;
  54
  55         add_wait_queue_exclusive(&call->waitq, &myself);
  56
  57         for (;;) {
  58                 switch (call->interruptibility) {
  59                 case RXRPC_INTERRUPTIBLE:
  60                 case RXRPC_PREINTERRUPTIBLE:
  61                         set_current_state(TASK_INTERRUPTIBLE);
  62                         break;
  63                 case RXRPC_UNINTERRUPTIBLE:
  64                 default:
  65                         set_current_state(TASK_UNINTERRUPTIBLE);
  66                         break;
  67                 }
  68
  69                 if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
  70                         break;
  71                 if ((call->interruptibility == RXRPC_INTERRUPTIBLE ||
  72                      call->interruptibility == RXRPC_PREINTERRUPTIBLE) &&
  73                     signal_pending(current)) {
  74                         ret = sock_intr_errno(*timeo);
  75                         break;
  76                 }
  77                 *timeo = schedule_timeout(*timeo);
  78         }
  79
  80         remove_wait_queue(&call->waitq, &myself);
  81         __set_current_state(TASK_RUNNING);
  82
  83 no_wait:
  84         if (ret == 0 && rxrpc_call_is_complete(call))
  85                 ret = call->error;
  86
  87         _leave(" = %d", ret);
  88         return ret;
  89 }
  90
  91 /*
  92  * Return true if there's sufficient Tx queue space.
  93  */
  94 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
  95 {
  96         if (_tx_win)
  97                 *_tx_win = call->tx_bottom;
  98         return call->tx_prepared - call->tx_bottom < 256;
  99 }
 100
 101 /*
 102  * Wait for space to appear in the Tx queue or a signal to occur.
 103  */
 104 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
 105                                          struct rxrpc_call *call,
 106                                          long *timeo)
 107 {
 108         for (;;) {
 109                 set_current_state(TASK_INTERRUPTIBLE);
 110                 if (rxrpc_check_tx_space(call, NULL))
 111                         return 0;
 112
 113                 if (rxrpc_call_is_complete(call))
 114                         return call->error;
 115
 116                 if (signal_pending(current))
 117                         return sock_intr_errno(*timeo);
 118
 119                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 120                 *timeo = schedule_timeout(*timeo);
 121         }
 122 }
 123
 124 /*
 125  * Wait for space to appear in the Tx queue uninterruptibly, but with
 126  * a timeout of 2*RTT if no progress was made and a signal occurred.
 127  */
 128 static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
 129                                             struct rxrpc_call *call)
 130 {
 131         rxrpc_seq_t tx_start, tx_win;
 132         signed long rtt, timeout;
 133
 134         rtt = READ_ONCE(call->peer->srtt_us) >> 3;
 135         rtt = usecs_to_jiffies(rtt) * 2;
 136         if (rtt < 2)
 137                 rtt = 2;
 138
 139         timeout = rtt;
 140         tx_start = smp_load_acquire(&call->acks_hard_ack);
 141
 142         for (;;) {
 143                 set_current_state(TASK_UNINTERRUPTIBLE);
 144
 145                 if (rxrpc_check_tx_space(call, &tx_win))
 146                         return 0;
 147
 148                 if (rxrpc_call_is_complete(call))
 149                         return call->error;
 150
 151                 if (timeout == 0 &&
 152                     tx_win == tx_start && signal_pending(current))
 153                         return -EINTR;
 154
 155                 if (tx_win != tx_start) {
 156                         timeout = rtt;
 157                         tx_start = tx_win;
 158                 }
 159
 160                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 161                 timeout = schedule_timeout(timeout);
 162         }
 163 }
 164
 165 /*
 166  * Wait for space to appear in the Tx queue uninterruptibly.
 167  */
 168 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
 169                                             struct rxrpc_call *call,
 170                                             long *timeo)
 171 {
 172         for (;;) {
 173                 set_current_state(TASK_UNINTERRUPTIBLE);
 174                 if (rxrpc_check_tx_space(call, NULL))
 175                         return 0;
 176
 177                 if (rxrpc_call_is_complete(call))
 178                         return call->error;
 179
 180                 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 181                 *timeo = schedule_timeout(*timeo);
 182         }
 183 }
 184
 185 /*
 186  * wait for space to appear in the transmit/ACK window
 187  * - caller holds the socket locked
 188  */
 189 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 190                                     struct rxrpc_call *call,
 191                                     long *timeo,
 192                                     bool waitall)
 193 {
 194         DECLARE_WAITQUEUE(myself, current);
 195         int ret;
 196
 197         _enter(",{%u,%u,%u,%u}",
 198                call->tx_bottom, call->acks_hard_ack, call->tx_top, call->tx_winsize);
 199
 200         add_wait_queue(&call->waitq, &myself);
 201
 202         switch (call->interruptibility) {
 203         case RXRPC_INTERRUPTIBLE:
 204                 if (waitall)
 205                         ret = rxrpc_wait_for_tx_window_waitall(rx, call);
 206                 else
 207                         ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
 208                 break;
 209         case RXRPC_PREINTERRUPTIBLE:
 210         case RXRPC_UNINTERRUPTIBLE:
 211         default:
 212                 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
 213                 break;
 214         }
 215
 216         remove_wait_queue(&call->waitq, &myself);
 217         set_current_state(TASK_RUNNING);
 218         _leave(" = %d", ret);
 219         return ret;
 220 }
 221
 222 /*
 223  * Notify the owner of the call that the transmit phase is ended and the last
 224  * packet has been queued.
 225  */
 226 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
 227                                 rxrpc_notify_end_tx_t notify_end_tx)
 228 {
 229         if (notify_end_tx)
 230                 notify_end_tx(&rx->sk, call, call->user_call_ID);
 231 }
 232
 233 /*
 234  * Queue a DATA packet for transmission, set the resend timeout and send
 235  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
 236  * in case the caller wants to do something with it.
 237  */
 238 static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 239                                struct rxrpc_txbuf *txb,
 240                                rxrpc_notify_end_tx_t notify_end_tx)
 241 {
 242         rxrpc_seq_t seq = txb->seq;
 243         bool poke, last = txb->flags & RXRPC_LAST_PACKET;
 244
 245         rxrpc_inc_stat(call->rxnet, stat_tx_data);
 246
 247         ASSERTCMP(txb->seq, ==, call->tx_prepared + 1);
 248
 249         /* We have to set the timestamp before queueing as the retransmit
 250          * algorithm can see the packet as soon as we queue it.
 251          */
 252         txb->last_sent = ktime_get_real();
 253
 254         if (last)
 255                 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue_last);
 256         else
 257                 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue);
 258
 259         /* Add the packet to the call's output buffer */
 260         spin_lock(&call->tx_lock);
 261         poke = list_empty(&call->tx_sendmsg);
 262         list_add_tail(&txb->call_link, &call->tx_sendmsg);
 263         call->tx_prepared = seq;
 264         if (last)
 265                 rxrpc_notify_end_tx(rx, call, notify_end_tx);
 266         spin_unlock(&call->tx_lock);
 267
 268         if (poke)
 269                 rxrpc_poke_call(call, rxrpc_call_poke_start);
 270 }
 271
 272 /*
 273  * send data through a socket
 274  * - must be called in process context
 275  * - The caller holds the call user access mutex, but not the socket lock.
 276  */
 277 static int rxrpc_send_data(struct rxrpc_sock *rx,
 278                            struct rxrpc_call *call,
 279                            struct msghdr *msg, size_t len,
 280                            rxrpc_notify_end_tx_t notify_end_tx,
 281                            bool *_dropped_lock)
 282 {
 283         struct rxrpc_txbuf *txb;
 284         struct sock *sk = &rx->sk;
 285         enum rxrpc_call_state state;
 286         long timeo;
 287         bool more = msg->msg_flags & MSG_MORE;
 288         int ret, copied = 0;
 289
 290         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 291
 292         ret = rxrpc_wait_to_be_connected(call, &timeo);
 293         if (ret < 0)
 294                 return ret;
 295
 296         if (call->conn->state == RXRPC_CONN_CLIENT_UNSECURED) {
 297                 ret = rxrpc_init_client_conn_security(call->conn);
 298                 if (ret < 0)
 299                         return ret;
 300         }
 301
 302         /* this should be in poll */
 303         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 304
 305 reload:
 306         ret = -EPIPE;
 307         if (sk->sk_shutdown & SEND_SHUTDOWN)
 308                 goto maybe_error;
 309         state = rxrpc_call_state(call);
 310         ret = -ESHUTDOWN;
 311         if (state >= RXRPC_CALL_COMPLETE)
 312                 goto maybe_error;
 313         ret = -EPROTO;
 314         if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
 315             state != RXRPC_CALL_SERVER_ACK_REQUEST &&
 316             state != RXRPC_CALL_SERVER_SEND_REPLY) {
 317                 /* Request phase complete for this client call */
 318                 trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send,
 319                                   call->cid, call->call_id, call->rx_consumed,
 320                                   0, -EPROTO);
 321                 goto maybe_error;
 322         }
 323
 324         ret = -EMSGSIZE;
 325         if (call->tx_total_len != -1) {
 326                 if (len - copied > call->tx_total_len)
 327                         goto maybe_error;
 328                 if (!more && len - copied != call->tx_total_len)
 329                         goto maybe_error;
 330         }
 331
 332         txb = call->tx_pending;
 333         call->tx_pending = NULL;
 334         if (txb)
 335                 rxrpc_see_txbuf(txb, rxrpc_txbuf_see_send_more);
 336
 337         do {
 338                 if (!txb) {
 339                         size_t remain;
 340
 341                         _debug("alloc");
 342
 343                         if (!rxrpc_check_tx_space(call, NULL))
 344                                 goto wait_for_space;
 345
 346                         /* Work out the maximum size of a packet.  Assume that
 347                          * the security header is going to be in the padded
 348                          * region (enc blocksize), but the trailer is not.
 349                          */
 350                         remain = more ? INT_MAX : msg_data_left(msg);
 351                         txb = call->conn->security->alloc_txbuf(call, remain, sk->sk_allocation);
 352                         if (IS_ERR(txb)) {
 353                                 ret = PTR_ERR(txb);
 354                                 goto maybe_error;
 355                         }
 356                 }
 357
 358                 _debug("append");
 359
 360                 /* append next segment of data to the current buffer */
 361                 if (msg_data_left(msg) > 0) {
 362                         size_t copy = min_t(size_t, txb->space, msg_data_left(msg));
 363
 364                         _debug("add %zu", copy);
 365                         if (!copy_from_iter_full(txb->kvec[0].iov_base + txb->offset,
 366                                                  copy, &msg->msg_iter))
 367                                 goto efault;
 368                         _debug("added");
 369                         txb->space -= copy;
 370                         txb->len += copy;
 371                         txb->offset += copy;
 372                         copied += copy;
 373                         if (call->tx_total_len != -1)
 374                                 call->tx_total_len -= copy;
 375                 }
 376
 377                 /* check for the far side aborting the call or a network error
 378                  * occurring */
 379                 if (rxrpc_call_is_complete(call))
 380                         goto call_terminated;
 381
 382                 /* add the packet to the send queue if it's now full */
 383                 if (!txb->space ||
 384                     (msg_data_left(msg) == 0 && !more)) {
 385                         if (msg_data_left(msg) == 0 && !more)
 386                                 txb->flags |= RXRPC_LAST_PACKET;
 387                         else if (call->tx_top - call->acks_hard_ack <
 388                                  call->tx_winsize)
 389                                 txb->flags |= RXRPC_MORE_PACKETS;
 390
 391                         ret = call->security->secure_packet(call, txb);
 392                         if (ret < 0)
 393                                 goto out;
 394
 395                         txb->kvec[0].iov_len += txb->len;
 396                         txb->len = txb->kvec[0].iov_len;
 397                         rxrpc_queue_packet(rx, call, txb, notify_end_tx);
 398                         txb = NULL;
 399                 }
 400         } while (msg_data_left(msg) > 0);
 401
 402 success:
 403         ret = copied;
 404         if (rxrpc_call_is_complete(call) &&
 405             call->error < 0)
 406                 ret = call->error;
 407 out:
 408         call->tx_pending = txb;
 409         _leave(" = %d", ret);
 410         return ret;
 411
 412 call_terminated:
 413         rxrpc_put_txbuf(txb, rxrpc_txbuf_put_send_aborted);
 414         _leave(" = %d", call->error);
 415         return call->error;
 416
 417 maybe_error:
 418         if (copied)
 419                 goto success;
 420         goto out;
 421
 422 efault:
 423         ret = -EFAULT;
 424         goto out;
 425
 426 wait_for_space:
 427         ret = -EAGAIN;
 428         if (msg->msg_flags & MSG_DONTWAIT)
 429                 goto maybe_error;
 430         mutex_unlock(&call->user_mutex);
 431         *_dropped_lock = true;
 432         ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
 433                                        msg->msg_flags & MSG_WAITALL);
 434         if (ret < 0)
 435                 goto maybe_error;
 436         if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
 437                 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
 438                         ret = sock_intr_errno(timeo);
 439                         goto maybe_error;
 440                 }
 441         } else {
 442                 mutex_lock(&call->user_mutex);
 443         }
 444         *_dropped_lock = false;
 445         goto reload;
 446 }
 447
 448 /*
 449  * extract control messages from the sendmsg() control buffer
 450  */
 451 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
 452 {
 453         struct cmsghdr *cmsg;
 454         bool got_user_ID = false;
 455         int len;
 456
 457         if (msg->msg_controllen == 0)
 458                 return -EINVAL;
 459
 460         for_each_cmsghdr(cmsg, msg) {
 461                 if (!CMSG_OK(msg, cmsg))
 462                         return -EINVAL;
 463
 464                 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
 465                 _debug("CMSG %d, %d, %d",
 466                        cmsg->cmsg_level, cmsg->cmsg_type, len);
 467
 468                 if (cmsg->cmsg_level != SOL_RXRPC)
 469                         continue;
 470
 471                 switch (cmsg->cmsg_type) {
 472                 case RXRPC_USER_CALL_ID:
 473                         if (msg->msg_flags & MSG_CMSG_COMPAT) {
 474                                 if (len != sizeof(u32))
 475                                         return -EINVAL;
 476                                 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
 477                         } else {
 478                                 if (len != sizeof(unsigned long))
 479                                         return -EINVAL;
 480                                 p->call.user_call_ID = *(unsigned long *)
 481                                         CMSG_DATA(cmsg);
 482                         }
 483                         got_user_ID = true;
 484                         break;
 485
 486                 case RXRPC_ABORT:
 487                         if (p->command != RXRPC_CMD_SEND_DATA)
 488                                 return -EINVAL;
 489                         p->command = RXRPC_CMD_SEND_ABORT;
 490                         if (len != sizeof(p->abort_code))
 491                                 return -EINVAL;
 492                         p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
 493                         if (p->abort_code == 0)
 494                                 return -EINVAL;
 495                         break;
 496
 497                 case RXRPC_CHARGE_ACCEPT:
 498                         if (p->command != RXRPC_CMD_SEND_DATA)
 499                                 return -EINVAL;
 500                         p->command = RXRPC_CMD_CHARGE_ACCEPT;
 501                         if (len != 0)
 502                                 return -EINVAL;
 503                         break;
 504
 505                 case RXRPC_EXCLUSIVE_CALL:
 506                         p->exclusive = true;
 507                         if (len != 0)
 508                                 return -EINVAL;
 509                         break;
 510
 511                 case RXRPC_UPGRADE_SERVICE:
 512                         p->upgrade = true;
 513                         if (len != 0)
 514                                 return -EINVAL;
 515                         break;
 516
 517                 case RXRPC_TX_LENGTH:
 518                         if (p->call.tx_total_len != -1 || len != sizeof(__s64))
 519                                 return -EINVAL;
 520                         p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
 521                         if (p->call.tx_total_len < 0)
 522                                 return -EINVAL;
 523                         break;
 524
 525                 case RXRPC_SET_CALL_TIMEOUT:
 526                         if (len & 3 || len < 4 || len > 12)
 527                                 return -EINVAL;
 528                         memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
 529                         p->call.nr_timeouts = len / 4;
 530                         if (p->call.timeouts.hard > INT_MAX / HZ)
 531                                 return -ERANGE;
 532                         if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
 533                                 return -ERANGE;
 534                         if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
 535                                 return -ERANGE;
 536                         break;
 537
 538                 default:
 539                         return -EINVAL;
 540                 }
 541         }
 542
 543         if (!got_user_ID)
 544                 return -EINVAL;
 545         if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
 546                 return -EINVAL;
 547         _leave(" = 0");
 548         return 0;
 549 }
 550
 551 /*
 552  * Create a new client call for sendmsg().
 553  * - Called with the socket lock held, which it must release.
 554  * - If it returns a call, the call's lock will need releasing by the caller.
 555  */
 556 static struct rxrpc_call *
 557 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 558                                   struct rxrpc_send_params *p)
 559         __releases(&rx->sk.sk_lock.slock)
 560         __acquires(&call->user_mutex)
 561 {
 562         struct rxrpc_conn_parameters cp;
 563         struct rxrpc_peer *peer;
 564         struct rxrpc_call *call;
 565         struct key *key;
 566
 567         DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
 568
 569         _enter("");
 570
 571         if (!msg->msg_name) {
 572                 release_sock(&rx->sk);
 573                 return ERR_PTR(-EDESTADDRREQ);
 574         }
 575
 576         peer = rxrpc_lookup_peer(rx->local, srx, GFP_KERNEL);
 577         if (!peer) {
 578                 release_sock(&rx->sk);
 579                 return ERR_PTR(-ENOMEM);
 580         }
 581
 582         key = rx->key;
 583         if (key && !rx->key->payload.data[0])
 584                 key = NULL;
 585
 586         memset(&cp, 0, sizeof(cp));
 587         cp.local                = rx->local;
 588         cp.peer                 = peer;
 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, &p->call, GFP_KERNEL,
 595                                      atomic_inc_return(&rxrpc_debug_id));
 596         /* The socket is now unlocked */
 597
 598         rxrpc_put_peer(peer, rxrpc_peer_put_application);
 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 {
 611         struct rxrpc_call *call;
 612         bool dropped_lock = false;
 613         int ret;
 614
 615         struct rxrpc_send_params p = {
 616                 .call.tx_total_len      = -1,
 617                 .call.user_call_ID      = 0,
 618                 .call.nr_timeouts       = 0,
 619                 .call.interruptibility  = RXRPC_INTERRUPTIBLE,
 620                 .abort_code             = 0,
 621                 .command                = RXRPC_CMD_SEND_DATA,
 622                 .exclusive              = false,
 623                 .upgrade                = false,
 624         };
 625
 626         _enter("");
 627
 628         ret = rxrpc_sendmsg_cmsg(msg, &p);
 629         if (ret < 0)
 630                 goto error_release_sock;
 631
 632         if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
 633                 ret = -EINVAL;
 634                 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
 635                         goto error_release_sock;
 636                 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
 637                 goto error_release_sock;
 638         }
 639
 640         call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
 641         if (!call) {
 642                 ret = -EBADSLT;
 643                 if (p.command != RXRPC_CMD_SEND_DATA)
 644                         goto error_release_sock;
 645                 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
 646                 /* The socket is now unlocked... */
 647                 if (IS_ERR(call))
 648                         return PTR_ERR(call);
 649                 /* ... and we have the call lock. */
 650                 p.call.nr_timeouts = 0;
 651                 ret = 0;
 652                 if (rxrpc_call_is_complete(call))
 653                         goto out_put_unlock;
 654         } else {
 655                 switch (rxrpc_call_state(call)) {
 656                 case RXRPC_CALL_CLIENT_AWAIT_CONN:
 657                 case RXRPC_CALL_SERVER_SECURING:
 658                         if (p.command == RXRPC_CMD_SEND_ABORT)
 659                                 break;
 660                         fallthrough;
 661                 case RXRPC_CALL_UNINITIALISED:
 662                 case RXRPC_CALL_SERVER_PREALLOC:
 663                         rxrpc_put_call(call, rxrpc_call_put_sendmsg);
 664                         ret = -EBUSY;
 665                         goto error_release_sock;
 666                 default:
 667                         break;
 668                 }
 669
 670                 ret = mutex_lock_interruptible(&call->user_mutex);
 671                 release_sock(&rx->sk);
 672                 if (ret < 0) {
 673                         ret = -ERESTARTSYS;
 674                         goto error_put;
 675                 }
 676
 677                 if (p.call.tx_total_len != -1) {
 678                         ret = -EINVAL;
 679                         if (call->tx_total_len != -1 ||
 680                             call->tx_pending ||
 681                             call->tx_top != 0)
 682                                 goto out_put_unlock;
 683                         call->tx_total_len = p.call.tx_total_len;
 684                 }
 685         }
 686
 687         switch (p.call.nr_timeouts) {
 688         case 3:
 689                 WRITE_ONCE(call->next_rx_timo, p.call.timeouts.normal);
 690                 fallthrough;
 691         case 2:
 692                 WRITE_ONCE(call->next_req_timo, p.call.timeouts.idle);
 693                 fallthrough;
 694         case 1:
 695                 if (p.call.timeouts.hard > 0) {
 696                         ktime_t delay = ms_to_ktime(p.call.timeouts.hard * MSEC_PER_SEC);
 697
 698                         WRITE_ONCE(call->expect_term_by,
 699                                    ktime_add(p.call.timeouts.hard,
 700                                              ktime_get_real()));
 701                         trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
 702                         rxrpc_poke_call(call, rxrpc_call_poke_set_timeout);
 703
 704                 }
 705                 break;
 706         }
 707
 708         if (rxrpc_call_is_complete(call)) {
 709                 /* it's too late for this call */
 710                 ret = -ESHUTDOWN;
 711         } else if (p.command == RXRPC_CMD_SEND_ABORT) {
 712                 rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED,
 713                                     rxrpc_abort_call_sendmsg);
 714                 ret = 0;
 715         } else if (p.command != RXRPC_CMD_SEND_DATA) {
 716                 ret = -EINVAL;
 717         } else {
 718                 ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
 719         }
 720
 721 out_put_unlock:
 722         if (!dropped_lock)
 723                 mutex_unlock(&call->user_mutex);
 724 error_put:
 725         rxrpc_put_call(call, rxrpc_call_put_sendmsg);
 726         _leave(" = %d", ret);
 727         return ret;
 728
 729 error_release_sock:
 730         release_sock(&rx->sk);
 731         return ret;
 732 }
 733
 734 /**
 735  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
 736  * @sock: The socket the call is on
 737  * @call: The call to send data through
 738  * @msg: The data to send
 739  * @len: The amount of data to send
 740  * @notify_end_tx: Notification that the last packet is queued.
 741  *
 742  * Allow a kernel service to send data on a call.  The call must be in an state
 743  * appropriate to sending data.  No control data should be supplied in @msg,
 744  * nor should an address be supplied.  MSG_MORE should be flagged if there's
 745  * more data to come, otherwise this data will end the transmission phase.
 746  */
 747 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 748                            struct msghdr *msg, size_t len,
 749                            rxrpc_notify_end_tx_t notify_end_tx)
 750 {
 751         bool dropped_lock = false;
 752         int ret;
 753
 754         _enter("{%d},", call->debug_id);
 755
 756         ASSERTCMP(msg->msg_name, ==, NULL);
 757         ASSERTCMP(msg->msg_control, ==, NULL);
 758
 759         mutex_lock(&call->user_mutex);
 760
 761         ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
 762                               notify_end_tx, &dropped_lock);
 763         if (ret == -ESHUTDOWN)
 764                 ret = call->error;
 765
 766         if (!dropped_lock)
 767                 mutex_unlock(&call->user_mutex);
 768         _leave(" = %d", ret);
 769         return ret;
 770 }
 771 EXPORT_SYMBOL(rxrpc_kernel_send_data);
 772
 773 /**
 774  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
 775  * @sock: The socket the call is on
 776  * @call: The call to be aborted
 777  * @abort_code: The abort code to stick into the ABORT packet
 778  * @error: Local error value
 779  * @why: Indication as to why.
 780  *
 781  * Allow a kernel service to abort a call, if it's still in an abortable state
 782  * and return true if the call was aborted, false if it was already complete.
 783  */
 784 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 785                              u32 abort_code, int error, enum rxrpc_abort_reason why)
 786 {
 787         bool aborted;
 788
 789         _enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
 790
 791         mutex_lock(&call->user_mutex);
 792         aborted = rxrpc_propose_abort(call, abort_code, error, why);
 793         mutex_unlock(&call->user_mutex);
 794         return aborted;
 795 }
 796 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
 797
 798 /**
 799  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
 800  * @sock: The socket the call is on
 801  * @call: The call to be informed
 802  * @tx_total_len: The amount of data to be transmitted for this call
 803  *
 804  * Allow a kernel service to set the total transmit length on a call.  This
 805  * allows buffer-to-packet encrypt-and-copy to be performed.
 806  *
 807  * This function is primarily for use for setting the reply length since the
 808  * request length can be set when beginning the call.
 809  */
 810 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
 811                                 s64 tx_total_len)
 812 {
 813         WARN_ON(call->tx_total_len != -1);
 814         call->tx_total_len = tx_total_len;
 815 }
 816 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);