fs/afs/rxrpc.c

   1 /* Maintain an RxRPC server socket to do AFS communications through
   2  *
   3  * Copyright (C) 2007 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 License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/slab.h>
  13 #include <linux/sched/signal.h>
  14
  15 #include <net/sock.h>
  16 #include <net/af_rxrpc.h>
  17 #include "internal.h"
  18 #include "afs_cm.h"
  19 #include "protocol_yfs.h"
  20
  21 struct workqueue_struct *afs_async_calls;
  22
  23 static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long);
  24 static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long);
  25 static void afs_delete_async_call(struct work_struct *);
  26 static void afs_process_async_call(struct work_struct *);
  27 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long);
  28 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long);
  29 static int afs_deliver_cm_op_id(struct afs_call *);
  30
  31 /* asynchronous incoming call initial processing */
  32 static const struct afs_call_type afs_RXCMxxxx = {
  33         .name           = "CB.xxxx",
  34         .deliver        = afs_deliver_cm_op_id,
  35 };
  36
  37 /*
  38  * open an RxRPC socket and bind it to be a server for callback notifications
  39  * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
  40  */
  41 int afs_open_socket(struct afs_net *net)
  42 {
  43         struct sockaddr_rxrpc srx;
  44         struct socket *socket;
  45         unsigned int min_level;
  46         int ret;
  47
  48         _enter("");
  49
  50         ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket);
  51         if (ret < 0)
  52                 goto error_1;
  53
  54         socket->sk->sk_allocation = GFP_NOFS;
  55
  56         /* bind the callback manager's address to make this a server socket */
  57         memset(&srx, 0, sizeof(srx));
  58         srx.srx_family                  = AF_RXRPC;
  59         srx.srx_service                 = CM_SERVICE;
  60         srx.transport_type              = SOCK_DGRAM;
  61         srx.transport_len               = sizeof(srx.transport.sin6);
  62         srx.transport.sin6.sin6_family  = AF_INET6;
  63         srx.transport.sin6.sin6_port    = htons(AFS_CM_PORT);
  64
  65         min_level = RXRPC_SECURITY_ENCRYPT;
  66         ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_MIN_SECURITY_LEVEL,
  67                                 (void *)&min_level, sizeof(min_level));
  68         if (ret < 0)
  69                 goto error_2;
  70
  71         ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  72         if (ret == -EADDRINUSE) {
  73                 srx.transport.sin6.sin6_port = 0;
  74                 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  75         }
  76         if (ret < 0)
  77                 goto error_2;
  78
  79         srx.srx_service = YFS_CM_SERVICE;
  80         ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  81         if (ret < 0)
  82                 goto error_2;
  83
  84         /* Ideally, we'd turn on service upgrade here, but we can't because
  85          * OpenAFS is buggy and leaks the userStatus field from packet to
  86          * packet and between FS packets and CB packets - so if we try to do an
  87          * upgrade on an FS packet, OpenAFS will leak that into the CB packet
  88          * it sends back to us.
  89          */
  90
  91         rxrpc_kernel_new_call_notification(socket, afs_rx_new_call,
  92                                            afs_rx_discard_new_call);
  93
  94         ret = kernel_listen(socket, INT_MAX);
  95         if (ret < 0)
  96                 goto error_2;
  97
  98         net->socket = socket;
  99         afs_charge_preallocation(&net->charge_preallocation_work);
 100         _leave(" = 0");
 101         return 0;
 102
 103 error_2:
 104         sock_release(socket);
 105 error_1:
 106         _leave(" = %d", ret);
 107         return ret;
 108 }
 109
 110 /*
 111  * close the RxRPC socket AFS was using
 112  */
 113 void afs_close_socket(struct afs_net *net)
 114 {
 115         _enter("");
 116
 117         kernel_listen(net->socket, 0);
 118         flush_workqueue(afs_async_calls);
 119
 120         if (net->spare_incoming_call) {
 121                 afs_put_call(net->spare_incoming_call);
 122                 net->spare_incoming_call = NULL;
 123         }
 124
 125         _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls));
 126         wait_var_event(&net->nr_outstanding_calls,
 127                        !atomic_read(&net->nr_outstanding_calls));
 128         _debug("no outstanding calls");
 129
 130         kernel_sock_shutdown(net->socket, SHUT_RDWR);
 131         flush_workqueue(afs_async_calls);
 132         sock_release(net->socket);
 133
 134         _debug("dework");
 135         _leave("");
 136 }
 137
 138 /*
 139  * Allocate a call.
 140  */
 141 static struct afs_call *afs_alloc_call(struct afs_net *net,
 142                                        const struct afs_call_type *type,
 143                                        gfp_t gfp)
 144 {
 145         struct afs_call *call;
 146         int o;
 147
 148         call = kzalloc(sizeof(*call), gfp);
 149         if (!call)
 150                 return NULL;
 151
 152         call->type = type;
 153         call->net = net;
 154         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 155         atomic_set(&call->usage, 1);
 156         INIT_WORK(&call->async_work, afs_process_async_call);
 157         init_waitqueue_head(&call->waitq);
 158         spin_lock_init(&call->state_lock);
 159         call->_iter = &call->iter;
 160
 161         o = atomic_inc_return(&net->nr_outstanding_calls);
 162         trace_afs_call(call, afs_call_trace_alloc, 1, o,
 163                        __builtin_return_address(0));
 164         return call;
 165 }
 166
 167 /*
 168  * Dispose of a reference on a call.
 169  */
 170 void afs_put_call(struct afs_call *call)
 171 {
 172         struct afs_net *net = call->net;
 173         int n = atomic_dec_return(&call->usage);
 174         int o = atomic_read(&net->nr_outstanding_calls);
 175
 176         trace_afs_call(call, afs_call_trace_put, n + 1, o,
 177                        __builtin_return_address(0));
 178
 179         ASSERTCMP(n, >=, 0);
 180         if (n == 0) {
 181                 ASSERT(!work_pending(&call->async_work));
 182                 ASSERT(call->type->name != NULL);
 183
 184                 if (call->rxcall) {
 185                         rxrpc_kernel_end_call(net->socket, call->rxcall);
 186                         call->rxcall = NULL;
 187                 }
 188                 if (call->type->destructor)
 189                         call->type->destructor(call);
 190
 191                 afs_put_server(call->net, call->cm_server);
 192                 afs_put_cb_interest(call->net, call->cbi);
 193                 afs_put_addrlist(call->alist);
 194                 kfree(call->request);
 195
 196                 trace_afs_call(call, afs_call_trace_free, 0, o,
 197                                __builtin_return_address(0));
 198                 kfree(call);
 199
 200                 o = atomic_dec_return(&net->nr_outstanding_calls);
 201                 if (o == 0)
 202                         wake_up_var(&net->nr_outstanding_calls);
 203         }
 204 }
 205
 206 static struct afs_call *afs_get_call(struct afs_call *call,
 207                                      enum afs_call_trace why)
 208 {
 209         int u = atomic_inc_return(&call->usage);
 210
 211         trace_afs_call(call, why, u,
 212                        atomic_read(&call->net->nr_outstanding_calls),
 213                        __builtin_return_address(0));
 214         return call;
 215 }
 216
 217 /*
 218  * Queue the call for actual work.
 219  */
 220 static void afs_queue_call_work(struct afs_call *call)
 221 {
 222         if (call->type->work) {
 223                 INIT_WORK(&call->work, call->type->work);
 224
 225                 afs_get_call(call, afs_call_trace_work);
 226                 if (!queue_work(afs_wq, &call->work))
 227                         afs_put_call(call);
 228         }
 229 }
 230
 231 /*
 232  * allocate a call with flat request and reply buffers
 233  */
 234 struct afs_call *afs_alloc_flat_call(struct afs_net *net,
 235                                      const struct afs_call_type *type,
 236                                      size_t request_size, size_t reply_max)
 237 {
 238         struct afs_call *call;
 239
 240         call = afs_alloc_call(net, type, GFP_NOFS);
 241         if (!call)
 242                 goto nomem_call;
 243
 244         if (request_size) {
 245                 call->request_size = request_size;
 246                 call->request = kmalloc(request_size, GFP_NOFS);
 247                 if (!call->request)
 248                         goto nomem_free;
 249         }
 250
 251         if (reply_max) {
 252                 call->reply_max = reply_max;
 253                 call->buffer = kmalloc(reply_max, GFP_NOFS);
 254                 if (!call->buffer)
 255                         goto nomem_free;
 256         }
 257
 258         afs_extract_to_buf(call, call->reply_max);
 259         call->operation_ID = type->op;
 260         init_waitqueue_head(&call->waitq);
 261         return call;
 262
 263 nomem_free:
 264         afs_put_call(call);
 265 nomem_call:
 266         return NULL;
 267 }
 268
 269 /*
 270  * clean up a call with flat buffer
 271  */
 272 void afs_flat_call_destructor(struct afs_call *call)
 273 {
 274         _enter("");
 275
 276         kfree(call->request);
 277         call->request = NULL;
 278         kfree(call->buffer);
 279         call->buffer = NULL;
 280 }
 281
 282 #define AFS_BVEC_MAX 8
 283
 284 /*
 285  * Load the given bvec with the next few pages.
 286  */
 287 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg,
 288                           struct bio_vec *bv, pgoff_t first, pgoff_t last,
 289                           unsigned offset)
 290 {
 291         struct page *pages[AFS_BVEC_MAX];
 292         unsigned int nr, n, i, to, bytes = 0;
 293
 294         nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX);
 295         n = find_get_pages_contig(call->mapping, first, nr, pages);
 296         ASSERTCMP(n, ==, nr);
 297
 298         msg->msg_flags |= MSG_MORE;
 299         for (i = 0; i < nr; i++) {
 300                 to = PAGE_SIZE;
 301                 if (first + i >= last) {
 302                         to = call->last_to;
 303                         msg->msg_flags &= ~MSG_MORE;
 304                 }
 305                 bv[i].bv_page = pages[i];
 306                 bv[i].bv_len = to - offset;
 307                 bv[i].bv_offset = offset;
 308                 bytes += to - offset;
 309                 offset = 0;
 310         }
 311
 312         iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes);
 313 }
 314
 315 /*
 316  * Advance the AFS call state when the RxRPC call ends the transmit phase.
 317  */
 318 static void afs_notify_end_request_tx(struct sock *sock,
 319                                       struct rxrpc_call *rxcall,
 320                                       unsigned long call_user_ID)
 321 {
 322         struct afs_call *call = (struct afs_call *)call_user_ID;
 323
 324         afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY);
 325 }
 326
 327 /*
 328  * attach the data from a bunch of pages on an inode to a call
 329  */
 330 static int afs_send_pages(struct afs_call *call, struct msghdr *msg)
 331 {
 332         struct bio_vec bv[AFS_BVEC_MAX];
 333         unsigned int bytes, nr, loop, offset;
 334         pgoff_t first = call->first, last = call->last;
 335         int ret;
 336
 337         offset = call->first_offset;
 338         call->first_offset = 0;
 339
 340         do {
 341                 afs_load_bvec(call, msg, bv, first, last, offset);
 342                 trace_afs_send_pages(call, msg, first, last, offset);
 343
 344                 offset = 0;
 345                 bytes = msg->msg_iter.count;
 346                 nr = msg->msg_iter.nr_segs;
 347
 348                 ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg,
 349                                              bytes, afs_notify_end_request_tx);
 350                 for (loop = 0; loop < nr; loop++)
 351                         put_page(bv[loop].bv_page);
 352                 if (ret < 0)
 353                         break;
 354
 355                 first += nr;
 356         } while (first <= last);
 357
 358         trace_afs_sent_pages(call, call->first, last, first, ret);
 359         return ret;
 360 }
 361
 362 /*
 363  * Initiate a call and synchronously queue up the parameters for dispatch.  Any
 364  * error is stored into the call struct, which the caller must check for.
 365  */
 366 void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 367 {
 368         struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index];
 369         struct rxrpc_call *rxcall;
 370         struct msghdr msg;
 371         struct kvec iov[1];
 372         s64 tx_total_len;
 373         int ret;
 374
 375         _enter(",{%pISp},", &srx->transport);
 376
 377         ASSERT(call->type != NULL);
 378         ASSERT(call->type->name != NULL);
 379
 380         _debug("____MAKE %p{%s,%x} [%d]____",
 381                call, call->type->name, key_serial(call->key),
 382                atomic_read(&call->net->nr_outstanding_calls));
 383
 384         call->addr_ix = ac->index;
 385         call->alist = afs_get_addrlist(ac->alist);
 386
 387         /* Work out the length we're going to transmit.  This is awkward for
 388          * calls such as FS.StoreData where there's an extra injection of data
 389          * after the initial fixed part.
 390          */
 391         tx_total_len = call->request_size;
 392         if (call->send_pages) {
 393                 if (call->last == call->first) {
 394                         tx_total_len += call->last_to - call->first_offset;
 395                 } else {
 396                         /* It looks mathematically like you should be able to
 397                          * combine the following lines with the ones above, but
 398                          * unsigned arithmetic is fun when it wraps...
 399                          */
 400                         tx_total_len += PAGE_SIZE - call->first_offset;
 401                         tx_total_len += call->last_to;
 402                         tx_total_len += (call->last - call->first - 1) * PAGE_SIZE;
 403                 }
 404         }
 405
 406         /* If the call is going to be asynchronous, we need an extra ref for
 407          * the call to hold itself so the caller need not hang on to its ref.
 408          */
 409         if (call->async)
 410                 afs_get_call(call, afs_call_trace_get);
 411
 412         /* create a call */
 413         rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key,
 414                                          (unsigned long)call,
 415                                          tx_total_len, gfp,
 416                                          (call->async ?
 417                                           afs_wake_up_async_call :
 418                                           afs_wake_up_call_waiter),
 419                                          call->upgrade,
 420                                          call->debug_id);
 421         if (IS_ERR(rxcall)) {
 422                 ret = PTR_ERR(rxcall);
 423                 call->error = ret;
 424                 goto error_kill_call;
 425         }
 426
 427         call->rxcall = rxcall;
 428
 429         /* send the request */
 430         iov[0].iov_base = call->request;
 431         iov[0].iov_len  = call->request_size;
 432
 433         msg.msg_name            = NULL;
 434         msg.msg_namelen         = 0;
 435         iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size);
 436         msg.msg_control         = NULL;
 437         msg.msg_controllen      = 0;
 438         msg.msg_flags           = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0);
 439
 440         ret = rxrpc_kernel_send_data(call->net->socket, rxcall,
 441                                      &msg, call->request_size,
 442                                      afs_notify_end_request_tx);
 443         if (ret < 0)
 444                 goto error_do_abort;
 445
 446         if (call->send_pages) {
 447                 ret = afs_send_pages(call, &msg);
 448                 if (ret < 0)
 449                         goto error_do_abort;
 450         }
 451
 452         /* Note that at this point, we may have received the reply or an abort
 453          * - and an asynchronous call may already have completed.
 454          *
 455          * afs_wait_for_call_to_complete(call, ac)
 456          * must be called to synchronously clean up.
 457          */
 458         return;
 459
 460 error_do_abort:
 461         if (ret != -ECONNABORTED) {
 462                 rxrpc_kernel_abort_call(call->net->socket, rxcall,
 463                                         RX_USER_ABORT, ret, "KSD");
 464         } else {
 465                 iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0);
 466                 rxrpc_kernel_recv_data(call->net->socket, rxcall,
 467                                        &msg.msg_iter, false,
 468                                        &call->abort_code, &call->service_id);
 469                 ac->abort_code = call->abort_code;
 470                 ac->responded = true;
 471         }
 472         call->error = ret;
 473         trace_afs_call_done(call);
 474 error_kill_call:
 475         if (call->type->done)
 476                 call->type->done(call);
 477
 478         /* We need to dispose of the extra ref we grabbed for an async call.
 479          * The call, however, might be queued on afs_async_calls and we need to
 480          * make sure we don't get any more notifications that might requeue it.
 481          */
 482         if (call->rxcall) {
 483                 rxrpc_kernel_end_call(call->net->socket, call->rxcall);
 484                 call->rxcall = NULL;
 485         }
 486         if (call->async) {
 487                 if (cancel_work_sync(&call->async_work))
 488                         afs_put_call(call);
 489                 afs_put_call(call);
 490         }
 491
 492         ac->error = ret;
 493         call->state = AFS_CALL_COMPLETE;
 494         _leave(" = %d", ret);
 495 }
 496
 497 /*
 498  * deliver messages to a call
 499  */
 500 static void afs_deliver_to_call(struct afs_call *call)
 501 {
 502         enum afs_call_state state;
 503         u32 abort_code, remote_abort = 0;
 504         int ret;
 505
 506         _enter("%s", call->type->name);
 507
 508         while (state = READ_ONCE(call->state),
 509                state == AFS_CALL_CL_AWAIT_REPLY ||
 510                state == AFS_CALL_SV_AWAIT_OP_ID ||
 511                state == AFS_CALL_SV_AWAIT_REQUEST ||
 512                state == AFS_CALL_SV_AWAIT_ACK
 513                ) {
 514                 if (state == AFS_CALL_SV_AWAIT_ACK) {
 515                         iov_iter_kvec(&call->iter, READ, NULL, 0, 0);
 516                         ret = rxrpc_kernel_recv_data(call->net->socket,
 517                                                      call->rxcall, &call->iter,
 518                                                      false, &remote_abort,
 519                                                      &call->service_id);
 520                         trace_afs_receive_data(call, &call->iter, false, ret);
 521
 522                         if (ret == -EINPROGRESS || ret == -EAGAIN)
 523                                 return;
 524                         if (ret < 0 || ret == 1) {
 525                                 if (ret == 1)
 526                                         ret = 0;
 527                                 goto call_complete;
 528                         }
 529                         return;
 530                 }
 531
 532                 if (call->want_reply_time &&
 533                     rxrpc_kernel_get_reply_time(call->net->socket,
 534                                                 call->rxcall,
 535                                                 &call->reply_time))
 536                         call->want_reply_time = false;
 537
 538                 ret = call->type->deliver(call);
 539                 state = READ_ONCE(call->state);
 540                 switch (ret) {
 541                 case 0:
 542                         afs_queue_call_work(call);
 543                         if (state == AFS_CALL_CL_PROC_REPLY) {
 544                                 if (call->cbi)
 545                                         set_bit(AFS_SERVER_FL_MAY_HAVE_CB,
 546                                                 &call->cbi->server->flags);
 547                                 goto call_complete;
 548                         }
 549                         ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY);
 550                         goto done;
 551                 case -EINPROGRESS:
 552                 case -EAGAIN:
 553                         goto out;
 554                 case -ECONNABORTED:
 555                         ASSERTCMP(state, ==, AFS_CALL_COMPLETE);
 556                         goto done;
 557                 case -ENOTSUPP:
 558                         abort_code = RXGEN_OPCODE;
 559                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 560                                                 abort_code, ret, "KIV");
 561                         goto local_abort;
 562                 case -EIO:
 563                         pr_err("kAFS: Call %u in bad state %u\n",
 564                                call->debug_id, state);
 565                         /* Fall through */
 566                 case -ENODATA:
 567                 case -EBADMSG:
 568                 case -EMSGSIZE:
 569                         abort_code = RXGEN_CC_UNMARSHAL;
 570                         if (state != AFS_CALL_CL_AWAIT_REPLY)
 571                                 abort_code = RXGEN_SS_UNMARSHAL;
 572                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 573                                                 abort_code, ret, "KUM");
 574                         goto local_abort;
 575                 default:
 576                         abort_code = RX_USER_ABORT;
 577                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 578                                                 abort_code, ret, "KER");
 579                         goto local_abort;
 580                 }
 581         }
 582
 583 done:
 584         if (call->type->done)
 585                 call->type->done(call);
 586         if (state == AFS_CALL_COMPLETE && call->incoming)
 587                 afs_put_call(call);
 588 out:
 589         _leave("");
 590         return;
 591
 592 local_abort:
 593         abort_code = 0;
 594 call_complete:
 595         afs_set_call_complete(call, ret, remote_abort);
 596         state = AFS_CALL_COMPLETE;
 597         goto done;
 598 }
 599
 600 /*
 601  * Wait synchronously for a call to complete and clean up the call struct.
 602  */
 603 long afs_wait_for_call_to_complete(struct afs_call *call,
 604                                    struct afs_addr_cursor *ac)
 605 {
 606         signed long rtt2, timeout;
 607         long ret;
 608         bool stalled = false;
 609         u64 rtt;
 610         u32 life, last_life;
 611         bool rxrpc_complete = false;
 612
 613         DECLARE_WAITQUEUE(myself, current);
 614
 615         _enter("");
 616
 617         ret = call->error;
 618         if (ret < 0)
 619                 goto out;
 620
 621         rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
 622         rtt2 = nsecs_to_jiffies64(rtt) * 2;
 623         if (rtt2 < 2)
 624                 rtt2 = 2;
 625
 626         timeout = rtt2;
 627         rxrpc_kernel_check_life(call->net->socket, call->rxcall, &last_life);
 628
 629         add_wait_queue(&call->waitq, &myself);
 630         for (;;) {
 631                 set_current_state(TASK_UNINTERRUPTIBLE);
 632
 633                 /* deliver any messages that are in the queue */
 634                 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) &&
 635                     call->need_attention) {
 636                         call->need_attention = false;
 637                         __set_current_state(TASK_RUNNING);
 638                         afs_deliver_to_call(call);
 639                         continue;
 640                 }
 641
 642                 if (afs_check_call_state(call, AFS_CALL_COMPLETE))
 643                         break;
 644
 645                 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall, &life)) {
 646                         /* rxrpc terminated the call. */
 647                         rxrpc_complete = true;
 648                         break;
 649                 }
 650
 651                 if (timeout == 0 &&
 652                     life == last_life && signal_pending(current)) {
 653                         if (stalled)
 654                                 break;
 655                         __set_current_state(TASK_RUNNING);
 656                         rxrpc_kernel_probe_life(call->net->socket, call->rxcall);
 657                         timeout = rtt2;
 658                         stalled = true;
 659                         continue;
 660                 }
 661
 662                 if (life != last_life) {
 663                         timeout = rtt2;
 664                         last_life = life;
 665                         stalled = false;
 666                 }
 667
 668                 timeout = schedule_timeout(timeout);
 669         }
 670
 671         remove_wait_queue(&call->waitq, &myself);
 672         __set_current_state(TASK_RUNNING);
 673
 674         if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) {
 675                 if (rxrpc_complete) {
 676                         afs_set_call_complete(call, call->error, call->abort_code);
 677                 } else {
 678                         /* Kill off the call if it's still live. */
 679                         _debug("call interrupted");
 680                         if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 681                                                     RX_USER_ABORT, -EINTR, "KWI"))
 682                                 afs_set_call_complete(call, -EINTR, 0);
 683                 }
 684         }
 685
 686         spin_lock_bh(&call->state_lock);
 687         ac->abort_code = call->abort_code;
 688         ac->error = call->error;
 689         spin_unlock_bh(&call->state_lock);
 690
 691         ret = ac->error;
 692         switch (ret) {
 693         case 0:
 694                 if (call->ret_reply0) {
 695                         ret = (long)call->reply[0];
 696                         call->reply[0] = NULL;
 697                 }
 698                 /* Fall through */
 699         case -ECONNABORTED:
 700                 ac->responded = true;
 701                 break;
 702         }
 703
 704 out:
 705         _debug("call complete");
 706         afs_put_call(call);
 707         _leave(" = %p", (void *)ret);
 708         return ret;
 709 }
 710
 711 /*
 712  * wake up a waiting call
 713  */
 714 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall,
 715                                     unsigned long call_user_ID)
 716 {
 717         struct afs_call *call = (struct afs_call *)call_user_ID;
 718
 719         call->need_attention = true;
 720         wake_up(&call->waitq);
 721 }
 722
 723 /*
 724  * wake up an asynchronous call
 725  */
 726 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall,
 727                                    unsigned long call_user_ID)
 728 {
 729         struct afs_call *call = (struct afs_call *)call_user_ID;
 730         int u;
 731
 732         trace_afs_notify_call(rxcall, call);
 733         call->need_attention = true;
 734
 735         u = atomic_fetch_add_unless(&call->usage, 1, 0);
 736         if (u != 0) {
 737                 trace_afs_call(call, afs_call_trace_wake, u,
 738                                atomic_read(&call->net->nr_outstanding_calls),
 739                                __builtin_return_address(0));
 740
 741                 if (!queue_work(afs_async_calls, &call->async_work))
 742                         afs_put_call(call);
 743         }
 744 }
 745
 746 /*
 747  * Delete an asynchronous call.  The work item carries a ref to the call struct
 748  * that we need to release.
 749  */
 750 static void afs_delete_async_call(struct work_struct *work)
 751 {
 752         struct afs_call *call = container_of(work, struct afs_call, async_work);
 753
 754         _enter("");
 755
 756         afs_put_call(call);
 757
 758         _leave("");
 759 }
 760
 761 /*
 762  * Perform I/O processing on an asynchronous call.  The work item carries a ref
 763  * to the call struct that we either need to release or to pass on.
 764  */
 765 static void afs_process_async_call(struct work_struct *work)
 766 {
 767         struct afs_call *call = container_of(work, struct afs_call, async_work);
 768
 769         _enter("");
 770
 771         if (call->state < AFS_CALL_COMPLETE && call->need_attention) {
 772                 call->need_attention = false;
 773                 afs_deliver_to_call(call);
 774         }
 775
 776         if (call->state == AFS_CALL_COMPLETE) {
 777                 /* We have two refs to release - one from the alloc and one
 778                  * queued with the work item - and we can't just deallocate the
 779                  * call because the work item may be queued again.
 780                  */
 781                 call->async_work.func = afs_delete_async_call;
 782                 if (!queue_work(afs_async_calls, &call->async_work))
 783                         afs_put_call(call);
 784         }
 785
 786         afs_put_call(call);
 787         _leave("");
 788 }
 789
 790 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID)
 791 {
 792         struct afs_call *call = (struct afs_call *)user_call_ID;
 793
 794         call->rxcall = rxcall;
 795 }
 796
 797 /*
 798  * Charge the incoming call preallocation.
 799  */
 800 void afs_charge_preallocation(struct work_struct *work)
 801 {
 802         struct afs_net *net =
 803                 container_of(work, struct afs_net, charge_preallocation_work);
 804         struct afs_call *call = net->spare_incoming_call;
 805
 806         for (;;) {
 807                 if (!call) {
 808                         call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL);
 809                         if (!call)
 810                                 break;
 811
 812                         call->async = true;
 813                         call->state = AFS_CALL_SV_AWAIT_OP_ID;
 814                         init_waitqueue_head(&call->waitq);
 815                         afs_extract_to_tmp(call);
 816                 }
 817
 818                 if (rxrpc_kernel_charge_accept(net->socket,
 819                                                afs_wake_up_async_call,
 820                                                afs_rx_attach,
 821                                                (unsigned long)call,
 822                                                GFP_KERNEL,
 823                                                call->debug_id) < 0)
 824                         break;
 825                 call = NULL;
 826         }
 827         net->spare_incoming_call = call;
 828 }
 829
 830 /*
 831  * Discard a preallocated call when a socket is shut down.
 832  */
 833 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall,
 834                                     unsigned long user_call_ID)
 835 {
 836         struct afs_call *call = (struct afs_call *)user_call_ID;
 837
 838         call->rxcall = NULL;
 839         afs_put_call(call);
 840 }
 841
 842 /*
 843  * Notification of an incoming call.
 844  */
 845 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall,
 846                             unsigned long user_call_ID)
 847 {
 848         struct afs_net *net = afs_sock2net(sk);
 849
 850         queue_work(afs_wq, &net->charge_preallocation_work);
 851 }
 852
 853 /*
 854  * Grab the operation ID from an incoming cache manager call.  The socket
 855  * buffer is discarded on error or if we don't yet have sufficient data.
 856  */
 857 static int afs_deliver_cm_op_id(struct afs_call *call)
 858 {
 859         int ret;
 860
 861         _enter("{%zu}", iov_iter_count(call->_iter));
 862
 863         /* the operation ID forms the first four bytes of the request data */
 864         ret = afs_extract_data(call, true);
 865         if (ret < 0)
 866                 return ret;
 867
 868         call->operation_ID = ntohl(call->tmp);
 869         afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST);
 870
 871         /* ask the cache manager to route the call (it'll change the call type
 872          * if successful) */
 873         if (!afs_cm_incoming_call(call))
 874                 return -ENOTSUPP;
 875
 876         trace_afs_cb_call(call);
 877
 878         /* pass responsibility for the remainer of this message off to the
 879          * cache manager op */
 880         return call->type->deliver(call);
 881 }
 882
 883 /*
 884  * Advance the AFS call state when an RxRPC service call ends the transmit
 885  * phase.
 886  */
 887 static void afs_notify_end_reply_tx(struct sock *sock,
 888                                     struct rxrpc_call *rxcall,
 889                                     unsigned long call_user_ID)
 890 {
 891         struct afs_call *call = (struct afs_call *)call_user_ID;
 892
 893         afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK);
 894 }
 895
 896 /*
 897  * send an empty reply
 898  */
 899 void afs_send_empty_reply(struct afs_call *call)
 900 {
 901         struct afs_net *net = call->net;
 902         struct msghdr msg;
 903
 904         _enter("");
 905
 906         rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0);
 907
 908         msg.msg_name            = NULL;
 909         msg.msg_namelen         = 0;
 910         iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0);
 911         msg.msg_control         = NULL;
 912         msg.msg_controllen      = 0;
 913         msg.msg_flags           = 0;
 914
 915         switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0,
 916                                        afs_notify_end_reply_tx)) {
 917         case 0:
 918                 _leave(" [replied]");
 919                 return;
 920
 921         case -ENOMEM:
 922                 _debug("oom");
 923                 rxrpc_kernel_abort_call(net->socket, call->rxcall,
 924                                         RX_USER_ABORT, -ENOMEM, "KOO");
 925                 /* Fall through */
 926         default:
 927                 _leave(" [error]");
 928                 return;
 929         }
 930 }
 931
 932 /*
 933  * send a simple reply
 934  */
 935 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 936 {
 937         struct afs_net *net = call->net;
 938         struct msghdr msg;
 939         struct kvec iov[1];
 940         int n;
 941
 942         _enter("");
 943
 944         rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len);
 945
 946         iov[0].iov_base         = (void *) buf;
 947         iov[0].iov_len          = len;
 948         msg.msg_name            = NULL;
 949         msg.msg_namelen         = 0;
 950         iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len);
 951         msg.msg_control         = NULL;
 952         msg.msg_controllen      = 0;
 953         msg.msg_flags           = 0;
 954
 955         n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len,
 956                                    afs_notify_end_reply_tx);
 957         if (n >= 0) {
 958                 /* Success */
 959                 _leave(" [replied]");
 960                 return;
 961         }
 962
 963         if (n == -ENOMEM) {
 964                 _debug("oom");
 965                 rxrpc_kernel_abort_call(net->socket, call->rxcall,
 966                                         RX_USER_ABORT, -ENOMEM, "KOO");
 967         }
 968         _leave(" [error]");
 969 }
 970
 971 /*
 972  * Extract a piece of data from the received data socket buffers.
 973  */
 974 int afs_extract_data(struct afs_call *call, bool want_more)
 975 {
 976         struct afs_net *net = call->net;
 977         struct iov_iter *iter = call->_iter;
 978         enum afs_call_state state;
 979         u32 remote_abort = 0;
 980         int ret;
 981
 982         _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more);
 983
 984         ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,
 985                                      want_more, &remote_abort,
 986                                      &call->service_id);
 987         if (ret == 0 || ret == -EAGAIN)
 988                 return ret;
 989
 990         state = READ_ONCE(call->state);
 991         if (ret == 1) {
 992                 switch (state) {
 993                 case AFS_CALL_CL_AWAIT_REPLY:
 994                         afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY);
 995                         break;
 996                 case AFS_CALL_SV_AWAIT_REQUEST:
 997                         afs_set_call_state(call, state, AFS_CALL_SV_REPLYING);
 998                         break;
 999                 case AFS_CALL_COMPLETE:
1000                         kdebug("prem complete %d", call->error);
1001                         return afs_io_error(call, afs_io_error_extract);
1002                 default:
1003                         break;
1004                 }
1005                 return 0;
1006         }
1007
1008         afs_set_call_complete(call, ret, remote_abort);
1009         return ret;
1010 }
1011
1012 /*
1013  * Log protocol error production.
1014  */
1015 noinline int afs_protocol_error(struct afs_call *call, int error,
1016                                 enum afs_eproto_cause cause)
1017 {
1018         trace_afs_protocol_error(call, error, cause);
1019         return error;
1020 }