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