net/rxrpc/sendmsg.c

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