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         unsigned int win_size =
  26                 min_t(unsigned int, call->tx_winsize,
  27                       call->cong_cwnd + call->cong_extra);
  28         rxrpc_seq_t tx_win = READ_ONCE(call->tx_hard_ack);
  29
  30         if (_tx_win)
  31                 *_tx_win = tx_win;
  32         return call->tx_top - tx_win < win_size;
  33 }
  34
  35 /*
  36  * Wait for space to appear in the Tx queue or a signal to occur.
  37  */
  38 static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
  39                                          struct rxrpc_call *call,
  40                                          long *timeo)
  41 {
  42         for (;;) {
  43                 set_current_state(TASK_INTERRUPTIBLE);
  44                 if (rxrpc_check_tx_space(call, NULL))
  45                         return 0;
  46
  47                 if (call->state >= RXRPC_CALL_COMPLETE)
  48                         return call->error;
  49
  50                 if (signal_pending(current))
  51                         return sock_intr_errno(*timeo);
  52
  53                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
  54                 *timeo = schedule_timeout(*timeo);
  55         }
  56 }
  57
  58 /*
  59  * Wait for space to appear in the Tx queue uninterruptibly, but with
  60  * a timeout of 2*RTT if no progress was made and a signal occurred.
  61  */
  62 static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
  63                                             struct rxrpc_call *call)
  64 {
  65         rxrpc_seq_t tx_start, tx_win;
  66         signed long rtt, timeout;
  67
  68         rtt = READ_ONCE(call->peer->srtt_us) >> 3;
  69         rtt = usecs_to_jiffies(rtt) * 2;
  70         if (rtt < 2)
  71                 rtt = 2;
  72
  73         timeout = rtt;
  74         tx_start = READ_ONCE(call->tx_hard_ack);
  75
  76         for (;;) {
  77                 set_current_state(TASK_UNINTERRUPTIBLE);
  78
  79                 tx_win = READ_ONCE(call->tx_hard_ack);
  80                 if (rxrpc_check_tx_space(call, &tx_win))
  81                         return 0;
  82
  83                 if (call->state >= RXRPC_CALL_COMPLETE)
  84                         return call->error;
  85
  86                 if (timeout == 0 &&
  87                     tx_win == tx_start && signal_pending(current))
  88                         return -EINTR;
  89
  90                 if (tx_win != tx_start) {
  91                         timeout = rtt;
  92                         tx_start = tx_win;
  93                 }
  94
  95                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
  96                 timeout = schedule_timeout(timeout);
  97         }
  98 }
  99
 100 /*
 101  * Wait for space to appear in the Tx queue uninterruptibly.
 102  */
 103 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
 104                                             struct rxrpc_call *call,
 105                                             long *timeo)
 106 {
 107         for (;;) {
 108                 set_current_state(TASK_UNINTERRUPTIBLE);
 109                 if (rxrpc_check_tx_space(call, NULL))
 110                         return 0;
 111
 112                 if (call->state >= RXRPC_CALL_COMPLETE)
 113                         return call->error;
 114
 115                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
 116                 *timeo = schedule_timeout(*timeo);
 117         }
 118 }
 119
 120 /*
 121  * wait for space to appear in the transmit/ACK window
 122  * - caller holds the socket locked
 123  */
 124 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 125                                     struct rxrpc_call *call,
 126                                     long *timeo,
 127                                     bool waitall)
 128 {
 129         DECLARE_WAITQUEUE(myself, current);
 130         int ret;
 131
 132         _enter(",{%u,%u,%u}",
 133                call->tx_hard_ack, call->tx_top, call->tx_winsize);
 134
 135         add_wait_queue(&call->waitq, &myself);
 136
 137         switch (call->interruptibility) {
 138         case RXRPC_INTERRUPTIBLE:
 139                 if (waitall)
 140                         ret = rxrpc_wait_for_tx_window_waitall(rx, call);
 141                 else
 142                         ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
 143                 break;
 144         case RXRPC_PREINTERRUPTIBLE:
 145         case RXRPC_UNINTERRUPTIBLE:
 146         default:
 147                 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
 148                 break;
 149         }
 150
 151         remove_wait_queue(&call->waitq, &myself);
 152         set_current_state(TASK_RUNNING);
 153         _leave(" = %d", ret);
 154         return ret;
 155 }
 156
 157 /*
 158  * Schedule an instant Tx resend.
 159  */
 160 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
 161 {
 162         spin_lock_bh(&call->lock);
 163
 164         if (call->state < RXRPC_CALL_COMPLETE) {
 165                 call->rxtx_annotations[ix] =
 166                         (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
 167                         RXRPC_TX_ANNO_RETRANS;
 168                 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 169                         rxrpc_queue_call(call);
 170         }
 171
 172         spin_unlock_bh(&call->lock);
 173 }
 174
 175 /*
 176  * Notify the owner of the call that the transmit phase is ended and the last
 177  * packet has been queued.
 178  */
 179 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
 180                                 rxrpc_notify_end_tx_t notify_end_tx)
 181 {
 182         if (notify_end_tx)
 183                 notify_end_tx(&rx->sk, call, call->user_call_ID);
 184 }
 185
 186 /*
 187  * Queue a DATA packet for transmission, set the resend timeout and send
 188  * the packet immediately.  Returns the error from rxrpc_send_data_packet()
 189  * in case the caller wants to do something with it.
 190  */
 191 static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 192                               struct sk_buff *skb, bool last,
 193                               rxrpc_notify_end_tx_t notify_end_tx)
 194 {
 195         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 196         unsigned long now;
 197         rxrpc_seq_t seq = sp->hdr.seq;
 198         int ret, ix;
 199         u8 annotation = RXRPC_TX_ANNO_UNACK;
 200
 201         _net("queue skb %p [%d]", skb, seq);
 202
 203         rxrpc_inc_stat(call->rxnet, stat_tx_data);
 204
 205         ASSERTCMP(seq, ==, call->tx_top + 1);
 206
 207         if (last)
 208                 annotation |= RXRPC_TX_ANNO_LAST;
 209
 210         /* We have to set the timestamp before queueing as the retransmit
 211          * algorithm can see the packet as soon as we queue it.
 212          */
 213         skb->tstamp = ktime_get_real();
 214
 215         ix = seq & RXRPC_RXTX_BUFF_MASK;
 216         rxrpc_get_skb(skb, rxrpc_skb_got);
 217         call->rxtx_annotations[ix] = annotation;
 218         smp_wmb();
 219         call->rxtx_buffer[ix] = skb;
 220         call->tx_top = seq;
 221         if (last)
 222                 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
 223         else
 224                 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
 225
 226         if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
 227                 _debug("________awaiting reply/ACK__________");
 228                 write_lock_bh(&call->state_lock);
 229                 switch (call->state) {
 230                 case RXRPC_CALL_CLIENT_SEND_REQUEST:
 231                         call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 232                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 233                         break;
 234                 case RXRPC_CALL_SERVER_ACK_REQUEST:
 235                         call->state = RXRPC_CALL_SERVER_SEND_REPLY;
 236                         now = jiffies;
 237                         WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
 238                         if (call->ackr_reason == RXRPC_ACK_DELAY)
 239                                 call->ackr_reason = 0;
 240                         trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
 241                         if (!last)
 242                                 break;
 243                         fallthrough;
 244                 case RXRPC_CALL_SERVER_SEND_REPLY:
 245                         call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
 246                         rxrpc_notify_end_tx(rx, call, notify_end_tx);
 247                         break;
 248                 default:
 249                         break;
 250                 }
 251                 write_unlock_bh(&call->state_lock);
 252         }
 253
 254         if (seq == 1 && rxrpc_is_client_call(call))
 255                 rxrpc_expose_client_call(call);
 256
 257         ret = rxrpc_send_data_packet(call, skb, false);
 258         if (ret < 0) {
 259                 switch (ret) {
 260                 case -ENETUNREACH:
 261                 case -EHOSTUNREACH:
 262                 case -ECONNREFUSED:
 263                         rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
 264                                                   0, ret);
 265                         goto out;
 266                 }
 267                 _debug("need instant resend %d", ret);
 268                 rxrpc_instant_resend(call, ix);
 269         } else {
 270                 unsigned long now = jiffies;
 271                 unsigned long resend_at = now + call->peer->rto_j;
 272
 273                 WRITE_ONCE(call->resend_at, resend_at);
 274                 rxrpc_reduce_call_timer(call, resend_at, now,
 275                                         rxrpc_timer_set_for_send);
 276         }
 277
 278 out:
 279         rxrpc_free_skb(skb, rxrpc_skb_freed);
 280         _leave(" = %d", ret);
 281         return ret;
 282 }
 283
 284 /*
 285  * send data through a socket
 286  * - must be called in process context
 287  * - The caller holds the call user access mutex, but not the socket lock.
 288  */
 289 static int rxrpc_send_data(struct rxrpc_sock *rx,
 290                            struct rxrpc_call *call,
 291                            struct msghdr *msg, size_t len,
 292                            rxrpc_notify_end_tx_t notify_end_tx,
 293                            bool *_dropped_lock)
 294 {
 295         struct rxrpc_skb_priv *sp;
 296         struct sk_buff *skb;
 297         struct sock *sk = &rx->sk;
 298         enum rxrpc_call_state state;
 299         long timeo;
 300         bool more = msg->msg_flags & MSG_MORE;
 301         int ret, copied = 0;
 302
 303         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
 304
 305         /* this should be in poll */
 306         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 307
 308 reload:
 309         ret = -EPIPE;
 310         if (sk->sk_shutdown & SEND_SHUTDOWN)
 311                 goto maybe_error;
 312         state = READ_ONCE(call->state);
 313         ret = -ESHUTDOWN;
 314         if (state >= RXRPC_CALL_COMPLETE)
 315                 goto maybe_error;
 316         ret = -EPROTO;
 317         if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
 318             state != RXRPC_CALL_SERVER_ACK_REQUEST &&
 319             state != RXRPC_CALL_SERVER_SEND_REPLY)
 320                 goto maybe_error;
 321
 322         ret = -EMSGSIZE;
 323         if (call->tx_total_len != -1) {
 324                 if (len - copied > call->tx_total_len)
 325                         goto maybe_error;
 326                 if (!more && len - copied != call->tx_total_len)
 327                         goto maybe_error;
 328         }
 329
 330         skb = call->tx_pending;
 331         call->tx_pending = NULL;
 332         rxrpc_see_skb(skb, rxrpc_skb_seen);
 333
 334         do {
 335                 /* Check to see if there's a ping ACK to reply to. */
 336                 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
 337                         rxrpc_send_ack_packet(call, false, NULL);
 338
 339                 if (!skb) {
 340                         size_t remain, bufsize, chunk, offset;
 341
 342                         _debug("alloc");
 343
 344                         if (!rxrpc_check_tx_space(call, NULL))
 345                                 goto wait_for_space;
 346
 347                         /* Work out the maximum size of a packet.  Assume that
 348                          * the security header is going to be in the padded
 349                          * region (enc blocksize), but the trailer is not.
 350                          */
 351                         remain = more ? INT_MAX : msg_data_left(msg);
 352                         ret = call->conn->security->how_much_data(call, remain,
 353                                                                   &bufsize, &chunk, &offset);
 354                         if (ret < 0)
 355                                 goto maybe_error;
 356
 357                         _debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
 358
 359                         /* create a buffer that we can retain until it's ACK'd */
 360                         skb = sock_alloc_send_skb(
 361                                 sk, bufsize, msg->msg_flags & MSG_DONTWAIT, &ret);
 362                         if (!skb)
 363                                 goto maybe_error;
 364
 365                         sp = rxrpc_skb(skb);
 366                         rxrpc_new_skb(skb, rxrpc_skb_new);
 367
 368                         _debug("ALLOC SEND %p", skb);
 369
 370                         ASSERTCMP(skb->mark, ==, 0);
 371
 372                         __skb_put(skb, offset);
 373
 374                         sp->remain = chunk;
 375                         if (sp->remain > skb_tailroom(skb))
 376                                 sp->remain = skb_tailroom(skb);
 377
 378                         _net("skb: hr %d, tr %d, hl %d, rm %d",
 379                                skb_headroom(skb),
 380                                skb_tailroom(skb),
 381                                skb_headlen(skb),
 382                                sp->remain);
 383
 384                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 385                 }
 386
 387                 _debug("append");
 388                 sp = rxrpc_skb(skb);
 389
 390                 /* append next segment of data to the current buffer */
 391                 if (msg_data_left(msg) > 0) {
 392                         int copy = skb_tailroom(skb);
 393                         ASSERTCMP(copy, >, 0);
 394                         if (copy > msg_data_left(msg))
 395                                 copy = msg_data_left(msg);
 396                         if (copy > sp->remain)
 397                                 copy = sp->remain;
 398
 399                         _debug("add");
 400                         ret = skb_add_data(skb, &msg->msg_iter, copy);
 401                         _debug("added");
 402                         if (ret < 0)
 403                                 goto efault;
 404                         sp->remain -= copy;
 405                         skb->mark += copy;
 406                         copied += copy;
 407                         if (call->tx_total_len != -1)
 408                                 call->tx_total_len -= copy;
 409                 }
 410
 411                 /* check for the far side aborting the call or a network error
 412                  * occurring */
 413                 if (call->state == RXRPC_CALL_COMPLETE)
 414                         goto call_terminated;
 415
 416                 /* add the packet to the send queue if it's now full */
 417                 if (sp->remain <= 0 ||
 418                     (msg_data_left(msg) == 0 && !more)) {
 419                         struct rxrpc_connection *conn = call->conn;
 420                         uint32_t seq;
 421
 422                         seq = call->tx_top + 1;
 423
 424                         sp->hdr.seq     = seq;
 425                         sp->hdr._rsvd   = 0;
 426                         sp->hdr.flags   = conn->out_clientflag;
 427
 428                         if (msg_data_left(msg) == 0 && !more)
 429                                 sp->hdr.flags |= RXRPC_LAST_PACKET;
 430                         else if (call->tx_top - call->tx_hard_ack <
 431                                  call->tx_winsize)
 432                                 sp->hdr.flags |= RXRPC_MORE_PACKETS;
 433
 434                         ret = call->security->secure_packet(call, skb, skb->mark);
 435                         if (ret < 0)
 436                                 goto out;
 437
 438                         ret = rxrpc_queue_packet(rx, call, skb,
 439                                                  !msg_data_left(msg) && !more,
 440                                                  notify_end_tx);
 441                         /* Should check for failure here */
 442                         skb = NULL;
 443                 }
 444         } while (msg_data_left(msg) > 0);
 445
 446 success:
 447         ret = copied;
 448         if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE) {
 449                 read_lock_bh(&call->state_lock);
 450                 if (call->error < 0)
 451                         ret = call->error;
 452                 read_unlock_bh(&call->state_lock);
 453         }
 454 out:
 455         call->tx_pending = skb;
 456         _leave(" = %d", ret);
 457         return ret;
 458
 459 call_terminated:
 460         rxrpc_free_skb(skb, rxrpc_skb_freed);
 461         _leave(" = %d", call->error);
 462         return call->error;
 463
 464 maybe_error:
 465         if (copied)
 466                 goto success;
 467         goto out;
 468
 469 efault:
 470         ret = -EFAULT;
 471         goto out;
 472
 473 wait_for_space:
 474         ret = -EAGAIN;
 475         if (msg->msg_flags & MSG_DONTWAIT)
 476                 goto maybe_error;
 477         mutex_unlock(&call->user_mutex);
 478         *_dropped_lock = true;
 479         ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
 480                                        msg->msg_flags & MSG_WAITALL);
 481         if (ret < 0)
 482                 goto maybe_error;
 483         if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
 484                 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
 485                         ret = sock_intr_errno(timeo);
 486                         goto maybe_error;
 487                 }
 488         } else {
 489                 mutex_lock(&call->user_mutex);
 490         }
 491         *_dropped_lock = false;
 492         goto reload;
 493 }
 494
 495 /*
 496  * extract control messages from the sendmsg() control buffer
 497  */
 498 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
 499 {
 500         struct cmsghdr *cmsg;
 501         bool got_user_ID = false;
 502         int len;
 503
 504         if (msg->msg_controllen == 0)
 505                 return -EINVAL;
 506
 507         for_each_cmsghdr(cmsg, msg) {
 508                 if (!CMSG_OK(msg, cmsg))
 509                         return -EINVAL;
 510
 511                 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
 512                 _debug("CMSG %d, %d, %d",
 513                        cmsg->cmsg_level, cmsg->cmsg_type, len);
 514
 515                 if (cmsg->cmsg_level != SOL_RXRPC)
 516                         continue;
 517
 518                 switch (cmsg->cmsg_type) {
 519                 case RXRPC_USER_CALL_ID:
 520                         if (msg->msg_flags & MSG_CMSG_COMPAT) {
 521                                 if (len != sizeof(u32))
 522                                         return -EINVAL;
 523                                 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
 524                         } else {
 525                                 if (len != sizeof(unsigned long))
 526                                         return -EINVAL;
 527                                 p->call.user_call_ID = *(unsigned long *)
 528                                         CMSG_DATA(cmsg);
 529                         }
 530                         got_user_ID = true;
 531                         break;
 532
 533                 case RXRPC_ABORT:
 534                         if (p->command != RXRPC_CMD_SEND_DATA)
 535                                 return -EINVAL;
 536                         p->command = RXRPC_CMD_SEND_ABORT;
 537                         if (len != sizeof(p->abort_code))
 538                                 return -EINVAL;
 539                         p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
 540                         if (p->abort_code == 0)
 541                                 return -EINVAL;
 542                         break;
 543
 544                 case RXRPC_CHARGE_ACCEPT:
 545                         if (p->command != RXRPC_CMD_SEND_DATA)
 546                                 return -EINVAL;
 547                         p->command = RXRPC_CMD_CHARGE_ACCEPT;
 548                         if (len != 0)
 549                                 return -EINVAL;
 550                         break;
 551
 552                 case RXRPC_EXCLUSIVE_CALL:
 553                         p->exclusive = true;
 554                         if (len != 0)
 555                                 return -EINVAL;
 556                         break;
 557
 558                 case RXRPC_UPGRADE_SERVICE:
 559                         p->upgrade = true;
 560                         if (len != 0)
 561                                 return -EINVAL;
 562                         break;
 563
 564                 case RXRPC_TX_LENGTH:
 565                         if (p->call.tx_total_len != -1 || len != sizeof(__s64))
 566                                 return -EINVAL;
 567                         p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
 568                         if (p->call.tx_total_len < 0)
 569                                 return -EINVAL;
 570                         break;
 571
 572                 case RXRPC_SET_CALL_TIMEOUT:
 573                         if (len & 3 || len < 4 || len > 12)
 574                                 return -EINVAL;
 575                         memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
 576                         p->call.nr_timeouts = len / 4;
 577                         if (p->call.timeouts.hard > INT_MAX / HZ)
 578                                 return -ERANGE;
 579                         if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
 580                                 return -ERANGE;
 581                         if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
 582                                 return -ERANGE;
 583                         break;
 584
 585                 default:
 586                         return -EINVAL;
 587                 }
 588         }
 589
 590         if (!got_user_ID)
 591                 return -EINVAL;
 592         if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
 593                 return -EINVAL;
 594         _leave(" = 0");
 595         return 0;
 596 }
 597
 598 /*
 599  * Create a new client call for sendmsg().
 600  * - Called with the socket lock held, which it must release.
 601  * - If it returns a call, the call's lock will need releasing by the caller.
 602  */
 603 static struct rxrpc_call *
 604 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 605                                   struct rxrpc_send_params *p)
 606         __releases(&rx->sk.sk_lock.slock)
 607         __acquires(&call->user_mutex)
 608 {
 609         struct rxrpc_conn_parameters cp;
 610         struct rxrpc_call *call;
 611         struct key *key;
 612
 613         DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
 614
 615         _enter("");
 616
 617         if (!msg->msg_name) {
 618                 release_sock(&rx->sk);
 619                 return ERR_PTR(-EDESTADDRREQ);
 620         }
 621
 622         key = rx->key;
 623         if (key && !rx->key->payload.data[0])
 624                 key = NULL;
 625
 626         memset(&cp, 0, sizeof(cp));
 627         cp.local                = rx->local;
 628         cp.key                  = rx->key;
 629         cp.security_level       = rx->min_sec_level;
 630         cp.exclusive            = rx->exclusive | p->exclusive;
 631         cp.upgrade              = p->upgrade;
 632         cp.service_id           = srx->srx_service;
 633         call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
 634                                      atomic_inc_return(&rxrpc_debug_id));
 635         /* The socket is now unlocked */
 636
 637         rxrpc_put_peer(cp.peer);
 638         _leave(" = %p\n", call);
 639         return call;
 640 }
 641
 642 /*
 643  * send a message forming part of a client call through an RxRPC socket
 644  * - caller holds the socket locked
 645  * - the socket may be either a client socket or a server socket
 646  */
 647 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 648         __releases(&rx->sk.sk_lock.slock)
 649         __releases(&call->user_mutex)
 650 {
 651         enum rxrpc_call_state state;
 652         struct rxrpc_call *call;
 653         unsigned long now, j;
 654         bool dropped_lock = false;
 655         int ret;
 656
 657         struct rxrpc_send_params p = {
 658                 .call.tx_total_len      = -1,
 659                 .call.user_call_ID      = 0,
 660                 .call.nr_timeouts       = 0,
 661                 .call.interruptibility  = RXRPC_INTERRUPTIBLE,
 662                 .abort_code             = 0,
 663                 .command                = RXRPC_CMD_SEND_DATA,
 664                 .exclusive              = false,
 665                 .upgrade                = false,
 666         };
 667
 668         _enter("");
 669
 670         ret = rxrpc_sendmsg_cmsg(msg, &p);
 671         if (ret < 0)
 672                 goto error_release_sock;
 673
 674         if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
 675                 ret = -EINVAL;
 676                 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
 677                         goto error_release_sock;
 678                 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
 679                 goto error_release_sock;
 680         }
 681
 682         call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
 683         if (!call) {
 684                 ret = -EBADSLT;
 685                 if (p.command != RXRPC_CMD_SEND_DATA)
 686                         goto error_release_sock;
 687                 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
 688                 /* The socket is now unlocked... */
 689                 if (IS_ERR(call))
 690                         return PTR_ERR(call);
 691                 /* ... and we have the call lock. */
 692                 ret = 0;
 693                 if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE)
 694                         goto out_put_unlock;
 695         } else {
 696                 switch (READ_ONCE(call->state)) {
 697                 case RXRPC_CALL_UNINITIALISED:
 698                 case RXRPC_CALL_CLIENT_AWAIT_CONN:
 699                 case RXRPC_CALL_SERVER_PREALLOC:
 700                 case RXRPC_CALL_SERVER_SECURING:
 701                         rxrpc_put_call(call, rxrpc_call_put);
 702                         ret = -EBUSY;
 703                         goto error_release_sock;
 704                 default:
 705                         break;
 706                 }
 707
 708                 ret = mutex_lock_interruptible(&call->user_mutex);
 709                 release_sock(&rx->sk);
 710                 if (ret < 0) {
 711                         ret = -ERESTARTSYS;
 712                         goto error_put;
 713                 }
 714
 715                 if (p.call.tx_total_len != -1) {
 716                         ret = -EINVAL;
 717                         if (call->tx_total_len != -1 ||
 718                             call->tx_pending ||
 719                             call->tx_top != 0)
 720                                 goto error_put;
 721                         call->tx_total_len = p.call.tx_total_len;
 722                 }
 723         }
 724
 725         switch (p.call.nr_timeouts) {
 726         case 3:
 727                 j = msecs_to_jiffies(p.call.timeouts.normal);
 728                 if (p.call.timeouts.normal > 0 && j == 0)
 729                         j = 1;
 730                 WRITE_ONCE(call->next_rx_timo, j);
 731                 fallthrough;
 732         case 2:
 733                 j = msecs_to_jiffies(p.call.timeouts.idle);
 734                 if (p.call.timeouts.idle > 0 && j == 0)
 735                         j = 1;
 736                 WRITE_ONCE(call->next_req_timo, j);
 737                 fallthrough;
 738         case 1:
 739                 if (p.call.timeouts.hard > 0) {
 740                         j = msecs_to_jiffies(p.call.timeouts.hard);
 741                         now = jiffies;
 742                         j += now;
 743                         WRITE_ONCE(call->expect_term_by, j);
 744                         rxrpc_reduce_call_timer(call, j, now,
 745                                                 rxrpc_timer_set_for_hard);
 746                 }
 747                 break;
 748         }
 749
 750         state = READ_ONCE(call->state);
 751         _debug("CALL %d USR %lx ST %d on CONN %p",
 752                call->debug_id, call->user_call_ID, state, call->conn);
 753
 754         if (state >= RXRPC_CALL_COMPLETE) {
 755                 /* it's too late for this call */
 756                 ret = -ESHUTDOWN;
 757         } else if (p.command == RXRPC_CMD_SEND_ABORT) {
 758                 ret = 0;
 759                 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
 760                         ret = rxrpc_send_abort_packet(call);
 761         } else if (p.command != RXRPC_CMD_SEND_DATA) {
 762                 ret = -EINVAL;
 763         } else {
 764                 ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
 765         }
 766
 767 out_put_unlock:
 768         if (!dropped_lock)
 769                 mutex_unlock(&call->user_mutex);
 770 error_put:
 771         rxrpc_put_call(call, rxrpc_call_put);
 772         _leave(" = %d", ret);
 773         return ret;
 774
 775 error_release_sock:
 776         release_sock(&rx->sk);
 777         return ret;
 778 }
 779
 780 /**
 781  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
 782  * @sock: The socket the call is on
 783  * @call: The call to send data through
 784  * @msg: The data to send
 785  * @len: The amount of data to send
 786  * @notify_end_tx: Notification that the last packet is queued.
 787  *
 788  * Allow a kernel service to send data on a call.  The call must be in an state
 789  * appropriate to sending data.  No control data should be supplied in @msg,
 790  * nor should an address be supplied.  MSG_MORE should be flagged if there's
 791  * more data to come, otherwise this data will end the transmission phase.
 792  */
 793 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 794                            struct msghdr *msg, size_t len,
 795                            rxrpc_notify_end_tx_t notify_end_tx)
 796 {
 797         bool dropped_lock = false;
 798         int ret;
 799
 800         _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
 801
 802         ASSERTCMP(msg->msg_name, ==, NULL);
 803         ASSERTCMP(msg->msg_control, ==, NULL);
 804
 805         mutex_lock(&call->user_mutex);
 806
 807         _debug("CALL %d USR %lx ST %d on CONN %p",
 808                call->debug_id, call->user_call_ID, call->state, call->conn);
 809
 810         switch (READ_ONCE(call->state)) {
 811         case RXRPC_CALL_CLIENT_SEND_REQUEST:
 812         case RXRPC_CALL_SERVER_ACK_REQUEST:
 813         case RXRPC_CALL_SERVER_SEND_REPLY:
 814                 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
 815                                       notify_end_tx, &dropped_lock);
 816                 break;
 817         case RXRPC_CALL_COMPLETE:
 818                 read_lock_bh(&call->state_lock);
 819                 ret = call->error;
 820                 read_unlock_bh(&call->state_lock);
 821                 break;
 822         default:
 823                 /* Request phase complete for this client call */
 824                 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
 825                 ret = -EPROTO;
 826                 break;
 827         }
 828
 829         if (!dropped_lock)
 830                 mutex_unlock(&call->user_mutex);
 831         _leave(" = %d", ret);
 832         return ret;
 833 }
 834 EXPORT_SYMBOL(rxrpc_kernel_send_data);
 835
 836 /**
 837  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
 838  * @sock: The socket the call is on
 839  * @call: The call to be aborted
 840  * @abort_code: The abort code to stick into the ABORT packet
 841  * @error: Local error value
 842  * @why: 3-char string indicating why.
 843  *
 844  * Allow a kernel service to abort a call, if it's still in an abortable state
 845  * and return true if the call was aborted, false if it was already complete.
 846  */
 847 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 848                              u32 abort_code, int error, const char *why)
 849 {
 850         bool aborted;
 851
 852         _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
 853
 854         mutex_lock(&call->user_mutex);
 855
 856         aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
 857         if (aborted)
 858                 rxrpc_send_abort_packet(call);
 859
 860         mutex_unlock(&call->user_mutex);
 861         return aborted;
 862 }
 863 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
 864
 865 /**
 866  * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
 867  * @sock: The socket the call is on
 868  * @call: The call to be informed
 869  * @tx_total_len: The amount of data to be transmitted for this call
 870  *
 871  * Allow a kernel service to set the total transmit length on a call.  This
 872  * allows buffer-to-packet encrypt-and-copy to be performed.
 873  *
 874  * This function is primarily for use for setting the reply length since the
 875  * request length can be set when beginning the call.
 876  */
 877 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
 878                                 s64 tx_total_len)
 879 {
 880         WARN_ON(call->tx_total_len != -1);
 881         call->tx_total_len = tx_total_len;
 882 }
 883 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);