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                 default:
 576                         abort_code = RXGEN_CC_UNMARSHAL;
 577                         if (state != AFS_CALL_CL_AWAIT_REPLY)
 578                                 abort_code = RXGEN_SS_UNMARSHAL;
 579                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 580                                                 abort_code, ret, "KUM");
 581                         goto local_abort;
 582                 }
 583         }
 584
 585 done:
 586         if (call->type->done)
 587                 call->type->done(call);
 588         if (state == AFS_CALL_COMPLETE && call->incoming)
 589                 afs_put_call(call);
 590 out:
 591         _leave("");
 592         return;
 593
 594 local_abort:
 595         abort_code = 0;
 596 call_complete:
 597         afs_set_call_complete(call, ret, remote_abort);
 598         state = AFS_CALL_COMPLETE;
 599         goto done;
 600 }
 601
 602 /*
 603  * wait synchronously for a call to complete
 604  */
 605 static long afs_wait_for_call_to_complete(struct afs_call *call,
 606                                           struct afs_addr_cursor *ac)
 607 {
 608         signed long rtt2, timeout;
 609         long ret;
 610         bool stalled = false;
 611         u64 rtt;
 612         u32 life, last_life;
 613
 614         DECLARE_WAITQUEUE(myself, current);
 615
 616         _enter("");
 617
 618         rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
 619         rtt2 = nsecs_to_jiffies64(rtt) * 2;
 620         if (rtt2 < 2)
 621                 rtt2 = 2;
 622
 623         timeout = rtt2;
 624         last_life = rxrpc_kernel_check_life(call->net->socket, call->rxcall);
 625
 626         add_wait_queue(&call->waitq, &myself);
 627         for (;;) {
 628                 set_current_state(TASK_UNINTERRUPTIBLE);
 629
 630                 /* deliver any messages that are in the queue */
 631                 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) &&
 632                     call->need_attention) {
 633                         call->need_attention = false;
 634                         __set_current_state(TASK_RUNNING);
 635                         afs_deliver_to_call(call);
 636                         continue;
 637                 }
 638
 639                 if (afs_check_call_state(call, AFS_CALL_COMPLETE))
 640                         break;
 641
 642                 life = rxrpc_kernel_check_life(call->net->socket, call->rxcall);
 643                 if (timeout == 0 &&
 644                     life == last_life && signal_pending(current)) {
 645                         if (stalled)
 646                                 break;
 647                         __set_current_state(TASK_RUNNING);
 648                         rxrpc_kernel_probe_life(call->net->socket, call->rxcall);
 649                         timeout = rtt2;
 650                         stalled = true;
 651                         continue;
 652                 }
 653
 654                 if (life != last_life) {
 655                         timeout = rtt2;
 656                         last_life = life;
 657                         stalled = false;
 658                 }
 659
 660                 timeout = schedule_timeout(timeout);
 661         }
 662
 663         remove_wait_queue(&call->waitq, &myself);
 664         __set_current_state(TASK_RUNNING);
 665
 666         /* Kill off the call if it's still live. */
 667         if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) {
 668                 _debug("call interrupted");
 669                 if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 670                                             RX_USER_ABORT, -EINTR, "KWI"))
 671                         afs_set_call_complete(call, -EINTR, 0);
 672         }
 673
 674         spin_lock_bh(&call->state_lock);
 675         ac->abort_code = call->abort_code;
 676         ac->error = call->error;
 677         spin_unlock_bh(&call->state_lock);
 678
 679         ret = ac->error;
 680         switch (ret) {
 681         case 0:
 682                 if (call->ret_reply0) {
 683                         ret = (long)call->reply[0];
 684                         call->reply[0] = NULL;
 685                 }
 686                 /* Fall through */
 687         case -ECONNABORTED:
 688                 ac->responded = true;
 689                 break;
 690         }
 691
 692         _debug("call complete");
 693         afs_put_call(call);
 694         _leave(" = %p", (void *)ret);
 695         return ret;
 696 }
 697
 698 /*
 699  * wake up a waiting call
 700  */
 701 static void afs_wake_up_call_waiter(struct sock *sk, struct rxrpc_call *rxcall,
 702                                     unsigned long call_user_ID)
 703 {
 704         struct afs_call *call = (struct afs_call *)call_user_ID;
 705
 706         call->need_attention = true;
 707         wake_up(&call->waitq);
 708 }
 709
 710 /*
 711  * wake up an asynchronous call
 712  */
 713 static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall,
 714                                    unsigned long call_user_ID)
 715 {
 716         struct afs_call *call = (struct afs_call *)call_user_ID;
 717         int u;
 718
 719         trace_afs_notify_call(rxcall, call);
 720         call->need_attention = true;
 721
 722         u = atomic_fetch_add_unless(&call->usage, 1, 0);
 723         if (u != 0) {
 724                 trace_afs_call(call, afs_call_trace_wake, u,
 725                                atomic_read(&call->net->nr_outstanding_calls),
 726                                __builtin_return_address(0));
 727
 728                 if (!queue_work(afs_async_calls, &call->async_work))
 729                         afs_put_call(call);
 730         }
 731 }
 732
 733 /*
 734  * Delete an asynchronous call.  The work item carries a ref to the call struct
 735  * that we need to release.
 736  */
 737 static void afs_delete_async_call(struct work_struct *work)
 738 {
 739         struct afs_call *call = container_of(work, struct afs_call, async_work);
 740
 741         _enter("");
 742
 743         afs_put_call(call);
 744
 745         _leave("");
 746 }
 747
 748 /*
 749  * Perform I/O processing on an asynchronous call.  The work item carries a ref
 750  * to the call struct that we either need to release or to pass on.
 751  */
 752 static void afs_process_async_call(struct work_struct *work)
 753 {
 754         struct afs_call *call = container_of(work, struct afs_call, async_work);
 755
 756         _enter("");
 757
 758         if (call->state < AFS_CALL_COMPLETE && call->need_attention) {
 759                 call->need_attention = false;
 760                 afs_deliver_to_call(call);
 761         }
 762
 763         if (call->state == AFS_CALL_COMPLETE) {
 764                 /* We have two refs to release - one from the alloc and one
 765                  * queued with the work item - and we can't just deallocate the
 766                  * call because the work item may be queued again.
 767                  */
 768                 call->async_work.func = afs_delete_async_call;
 769                 if (!queue_work(afs_async_calls, &call->async_work))
 770                         afs_put_call(call);
 771         }
 772
 773         afs_put_call(call);
 774         _leave("");
 775 }
 776
 777 static void afs_rx_attach(struct rxrpc_call *rxcall, unsigned long user_call_ID)
 778 {
 779         struct afs_call *call = (struct afs_call *)user_call_ID;
 780
 781         call->rxcall = rxcall;
 782 }
 783
 784 /*
 785  * Charge the incoming call preallocation.
 786  */
 787 void afs_charge_preallocation(struct work_struct *work)
 788 {
 789         struct afs_net *net =
 790                 container_of(work, struct afs_net, charge_preallocation_work);
 791         struct afs_call *call = net->spare_incoming_call;
 792
 793         for (;;) {
 794                 if (!call) {
 795                         call = afs_alloc_call(net, &afs_RXCMxxxx, GFP_KERNEL);
 796                         if (!call)
 797                                 break;
 798
 799                         call->async = true;
 800                         call->state = AFS_CALL_SV_AWAIT_OP_ID;
 801                         init_waitqueue_head(&call->waitq);
 802                         afs_extract_to_tmp(call);
 803                 }
 804
 805                 if (rxrpc_kernel_charge_accept(net->socket,
 806                                                afs_wake_up_async_call,
 807                                                afs_rx_attach,
 808                                                (unsigned long)call,
 809                                                GFP_KERNEL,
 810                                                call->debug_id) < 0)
 811                         break;
 812                 call = NULL;
 813         }
 814         net->spare_incoming_call = call;
 815 }
 816
 817 /*
 818  * Discard a preallocated call when a socket is shut down.
 819  */
 820 static void afs_rx_discard_new_call(struct rxrpc_call *rxcall,
 821                                     unsigned long user_call_ID)
 822 {
 823         struct afs_call *call = (struct afs_call *)user_call_ID;
 824
 825         call->rxcall = NULL;
 826         afs_put_call(call);
 827 }
 828
 829 /*
 830  * Notification of an incoming call.
 831  */
 832 static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall,
 833                             unsigned long user_call_ID)
 834 {
 835         struct afs_net *net = afs_sock2net(sk);
 836
 837         queue_work(afs_wq, &net->charge_preallocation_work);
 838 }
 839
 840 /*
 841  * Grab the operation ID from an incoming cache manager call.  The socket
 842  * buffer is discarded on error or if we don't yet have sufficient data.
 843  */
 844 static int afs_deliver_cm_op_id(struct afs_call *call)
 845 {
 846         int ret;
 847
 848         _enter("{%zu}", iov_iter_count(call->_iter));
 849
 850         /* the operation ID forms the first four bytes of the request data */
 851         ret = afs_extract_data(call, true);
 852         if (ret < 0)
 853                 return ret;
 854
 855         call->operation_ID = ntohl(call->tmp);
 856         afs_set_call_state(call, AFS_CALL_SV_AWAIT_OP_ID, AFS_CALL_SV_AWAIT_REQUEST);
 857
 858         /* ask the cache manager to route the call (it'll change the call type
 859          * if successful) */
 860         if (!afs_cm_incoming_call(call))
 861                 return -ENOTSUPP;
 862
 863         trace_afs_cb_call(call);
 864
 865         /* pass responsibility for the remainer of this message off to the
 866          * cache manager op */
 867         return call->type->deliver(call);
 868 }
 869
 870 /*
 871  * Advance the AFS call state when an RxRPC service call ends the transmit
 872  * phase.
 873  */
 874 static void afs_notify_end_reply_tx(struct sock *sock,
 875                                     struct rxrpc_call *rxcall,
 876                                     unsigned long call_user_ID)
 877 {
 878         struct afs_call *call = (struct afs_call *)call_user_ID;
 879
 880         afs_set_call_state(call, AFS_CALL_SV_REPLYING, AFS_CALL_SV_AWAIT_ACK);
 881 }
 882
 883 /*
 884  * send an empty reply
 885  */
 886 void afs_send_empty_reply(struct afs_call *call)
 887 {
 888         struct afs_net *net = call->net;
 889         struct msghdr msg;
 890
 891         _enter("");
 892
 893         rxrpc_kernel_set_tx_length(net->socket, call->rxcall, 0);
 894
 895         msg.msg_name            = NULL;
 896         msg.msg_namelen         = 0;
 897         iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0);
 898         msg.msg_control         = NULL;
 899         msg.msg_controllen      = 0;
 900         msg.msg_flags           = 0;
 901
 902         switch (rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, 0,
 903                                        afs_notify_end_reply_tx)) {
 904         case 0:
 905                 _leave(" [replied]");
 906                 return;
 907
 908         case -ENOMEM:
 909                 _debug("oom");
 910                 rxrpc_kernel_abort_call(net->socket, call->rxcall,
 911                                         RX_USER_ABORT, -ENOMEM, "KOO");
 912         default:
 913                 _leave(" [error]");
 914                 return;
 915         }
 916 }
 917
 918 /*
 919  * send a simple reply
 920  */
 921 void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 922 {
 923         struct afs_net *net = call->net;
 924         struct msghdr msg;
 925         struct kvec iov[1];
 926         int n;
 927
 928         _enter("");
 929
 930         rxrpc_kernel_set_tx_length(net->socket, call->rxcall, len);
 931
 932         iov[0].iov_base         = (void *) buf;
 933         iov[0].iov_len          = len;
 934         msg.msg_name            = NULL;
 935         msg.msg_namelen         = 0;
 936         iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len);
 937         msg.msg_control         = NULL;
 938         msg.msg_controllen      = 0;
 939         msg.msg_flags           = 0;
 940
 941         n = rxrpc_kernel_send_data(net->socket, call->rxcall, &msg, len,
 942                                    afs_notify_end_reply_tx);
 943         if (n >= 0) {
 944                 /* Success */
 945                 _leave(" [replied]");
 946                 return;
 947         }
 948
 949         if (n == -ENOMEM) {
 950                 _debug("oom");
 951                 rxrpc_kernel_abort_call(net->socket, call->rxcall,
 952                                         RX_USER_ABORT, -ENOMEM, "KOO");
 953         }
 954         _leave(" [error]");
 955 }
 956
 957 /*
 958  * Extract a piece of data from the received data socket buffers.
 959  */
 960 int afs_extract_data(struct afs_call *call, bool want_more)
 961 {
 962         struct afs_net *net = call->net;
 963         struct iov_iter *iter = call->_iter;
 964         enum afs_call_state state;
 965         u32 remote_abort = 0;
 966         int ret;
 967
 968         _enter("{%s,%zu},%d", call->type->name, iov_iter_count(iter), want_more);
 969
 970         ret = rxrpc_kernel_recv_data(net->socket, call->rxcall, iter,
 971                                      want_more, &remote_abort,
 972                                      &call->service_id);
 973         if (ret == 0 || ret == -EAGAIN)
 974                 return ret;
 975
 976         state = READ_ONCE(call->state);
 977         if (ret == 1) {
 978                 switch (state) {
 979                 case AFS_CALL_CL_AWAIT_REPLY:
 980                         afs_set_call_state(call, state, AFS_CALL_CL_PROC_REPLY);
 981                         break;
 982                 case AFS_CALL_SV_AWAIT_REQUEST:
 983                         afs_set_call_state(call, state, AFS_CALL_SV_REPLYING);
 984                         break;
 985                 case AFS_CALL_COMPLETE:
 986                         kdebug("prem complete %d", call->error);
 987                         return afs_io_error(call, afs_io_error_extract);
 988                 default:
 989                         break;
 990                 }
 991                 return 0;
 992         }
 993
 994         afs_set_call_complete(call, ret, remote_abort);
 995         return ret;
 996 }
 997
 998 /*
 999  * Log protocol error production.
1000  */
1001 noinline int afs_protocol_error(struct afs_call *call, int error,
1002                                 enum afs_eproto_cause cause)
1003 {
1004         trace_afs_protocol_error(call, error, cause);
1005         return error;
1006 }