fs/afs/rxrpc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Maintain an RxRPC server socket to do AFS communications through
   3  *
   4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   5  * Written by David Howells (dhowells@redhat.com)
   6  */
   7
   8 #include <linux/slab.h>
   9 #include <linux/sched/signal.h>
  10
  11 #include <net/sock.h>
  12 #include <net/af_rxrpc.h>
  13 #include "internal.h"
  14 #include "afs_cm.h"
  15 #include "protocol_yfs.h"
  16
  17 struct workqueue_struct *afs_async_calls;
  18
  19 static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long);
  20 static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long);
  21 static void afs_delete_async_call(struct work_struct *);
  22 static void afs_process_async_call(struct work_struct *);
  23 static void afs_rx_new_call(struct sock *, struct rxrpc_call *, unsigned long);
  24 static void afs_rx_discard_new_call(struct rxrpc_call *, unsigned long);
  25 static int afs_deliver_cm_op_id(struct afs_call *);
  26
  27 /* asynchronous incoming call initial processing */
  28 static const struct afs_call_type afs_RXCMxxxx = {
  29         .name           = "CB.xxxx",
  30         .deliver        = afs_deliver_cm_op_id,
  31 };
  32
  33 /*
  34  * open an RxRPC socket and bind it to be a server for callback notifications
  35  * - the socket is left in blocking mode and non-blocking ops use MSG_DONTWAIT
  36  */
  37 int afs_open_socket(struct afs_net *net)
  38 {
  39         struct sockaddr_rxrpc srx;
  40         struct socket *socket;
  41         unsigned int min_level;
  42         int ret;
  43
  44         _enter("");
  45
  46         ret = sock_create_kern(net->net, AF_RXRPC, SOCK_DGRAM, PF_INET6, &socket);
  47         if (ret < 0)
  48                 goto error_1;
  49
  50         socket->sk->sk_allocation = GFP_NOFS;
  51
  52         /* bind the callback manager's address to make this a server socket */
  53         memset(&srx, 0, sizeof(srx));
  54         srx.srx_family                  = AF_RXRPC;
  55         srx.srx_service                 = CM_SERVICE;
  56         srx.transport_type              = SOCK_DGRAM;
  57         srx.transport_len               = sizeof(srx.transport.sin6);
  58         srx.transport.sin6.sin6_family  = AF_INET6;
  59         srx.transport.sin6.sin6_port    = htons(AFS_CM_PORT);
  60
  61         min_level = RXRPC_SECURITY_ENCRYPT;
  62         ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_MIN_SECURITY_LEVEL,
  63                                 (void *)&min_level, sizeof(min_level));
  64         if (ret < 0)
  65                 goto error_2;
  66
  67         ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  68         if (ret == -EADDRINUSE) {
  69                 srx.transport.sin6.sin6_port = 0;
  70                 ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  71         }
  72         if (ret < 0)
  73                 goto error_2;
  74
  75         srx.srx_service = YFS_CM_SERVICE;
  76         ret = kernel_bind(socket, (struct sockaddr *) &srx, sizeof(srx));
  77         if (ret < 0)
  78                 goto error_2;
  79
  80         /* Ideally, we'd turn on service upgrade here, but we can't because
  81          * OpenAFS is buggy and leaks the userStatus field from packet to
  82          * packet and between FS packets and CB packets - so if we try to do an
  83          * upgrade on an FS packet, OpenAFS will leak that into the CB packet
  84          * it sends back to us.
  85          */
  86
  87         rxrpc_kernel_new_call_notification(socket, afs_rx_new_call,
  88                                            afs_rx_discard_new_call);
  89
  90         ret = kernel_listen(socket, INT_MAX);
  91         if (ret < 0)
  92                 goto error_2;
  93
  94         net->socket = socket;
  95         afs_charge_preallocation(&net->charge_preallocation_work);
  96         _leave(" = 0");
  97         return 0;
  98
  99 error_2:
 100         sock_release(socket);
 101 error_1:
 102         _leave(" = %d", ret);
 103         return ret;
 104 }
 105
 106 /*
 107  * close the RxRPC socket AFS was using
 108  */
 109 void afs_close_socket(struct afs_net *net)
 110 {
 111         _enter("");
 112
 113         kernel_listen(net->socket, 0);
 114         flush_workqueue(afs_async_calls);
 115
 116         if (net->spare_incoming_call) {
 117                 afs_put_call(net->spare_incoming_call);
 118                 net->spare_incoming_call = NULL;
 119         }
 120
 121         _debug("outstanding %u", atomic_read(&net->nr_outstanding_calls));
 122         wait_var_event(&net->nr_outstanding_calls,
 123                        !atomic_read(&net->nr_outstanding_calls));
 124         _debug("no outstanding calls");
 125
 126         kernel_sock_shutdown(net->socket, SHUT_RDWR);
 127         flush_workqueue(afs_async_calls);
 128         sock_release(net->socket);
 129
 130         _debug("dework");
 131         _leave("");
 132 }
 133
 134 /*
 135  * Allocate a call.
 136  */
 137 static struct afs_call *afs_alloc_call(struct afs_net *net,
 138                                        const struct afs_call_type *type,
 139                                        gfp_t gfp)
 140 {
 141         struct afs_call *call;
 142         int o;
 143
 144         call = kzalloc(sizeof(*call), gfp);
 145         if (!call)
 146                 return NULL;
 147
 148         call->type = type;
 149         call->net = net;
 150         call->debug_id = atomic_inc_return(&rxrpc_debug_id);
 151         atomic_set(&call->usage, 1);
 152         INIT_WORK(&call->async_work, afs_process_async_call);
 153         init_waitqueue_head(&call->waitq);
 154         spin_lock_init(&call->state_lock);
 155         call->_iter = &call->iter;
 156
 157         o = atomic_inc_return(&net->nr_outstanding_calls);
 158         trace_afs_call(call, afs_call_trace_alloc, 1, o,
 159                        __builtin_return_address(0));
 160         return call;
 161 }
 162
 163 /*
 164  * Dispose of a reference on a call.
 165  */
 166 void afs_put_call(struct afs_call *call)
 167 {
 168         struct afs_net *net = call->net;
 169         int n = atomic_dec_return(&call->usage);
 170         int o = atomic_read(&net->nr_outstanding_calls);
 171
 172         trace_afs_call(call, afs_call_trace_put, n + 1, o,
 173                        __builtin_return_address(0));
 174
 175         ASSERTCMP(n, >=, 0);
 176         if (n == 0) {
 177                 ASSERT(!work_pending(&call->async_work));
 178                 ASSERT(call->type->name != NULL);
 179
 180                 if (call->rxcall) {
 181                         rxrpc_kernel_end_call(net->socket, call->rxcall);
 182                         call->rxcall = NULL;
 183                 }
 184                 if (call->type->destructor)
 185                         call->type->destructor(call);
 186
 187                 afs_put_server(call->net, call->server, afs_server_trace_put_call);
 188                 afs_put_cb_interest(call->net, call->cbi);
 189                 afs_put_addrlist(call->alist);
 190                 kfree(call->request);
 191
 192                 trace_afs_call(call, afs_call_trace_free, 0, o,
 193                                __builtin_return_address(0));
 194                 kfree(call);
 195
 196                 o = atomic_dec_return(&net->nr_outstanding_calls);
 197                 if (o == 0)
 198                         wake_up_var(&net->nr_outstanding_calls);
 199         }
 200 }
 201
 202 static struct afs_call *afs_get_call(struct afs_call *call,
 203                                      enum afs_call_trace why)
 204 {
 205         int u = atomic_inc_return(&call->usage);
 206
 207         trace_afs_call(call, why, u,
 208                        atomic_read(&call->net->nr_outstanding_calls),
 209                        __builtin_return_address(0));
 210         return call;
 211 }
 212
 213 /*
 214  * Queue the call for actual work.
 215  */
 216 static void afs_queue_call_work(struct afs_call *call)
 217 {
 218         if (call->type->work) {
 219                 INIT_WORK(&call->work, call->type->work);
 220
 221                 afs_get_call(call, afs_call_trace_work);
 222                 if (!queue_work(afs_wq, &call->work))
 223                         afs_put_call(call);
 224         }
 225 }
 226
 227 /*
 228  * allocate a call with flat request and reply buffers
 229  */
 230 struct afs_call *afs_alloc_flat_call(struct afs_net *net,
 231                                      const struct afs_call_type *type,
 232                                      size_t request_size, size_t reply_max)
 233 {
 234         struct afs_call *call;
 235
 236         call = afs_alloc_call(net, type, GFP_NOFS);
 237         if (!call)
 238                 goto nomem_call;
 239
 240         if (request_size) {
 241                 call->request_size = request_size;
 242                 call->request = kmalloc(request_size, GFP_NOFS);
 243                 if (!call->request)
 244                         goto nomem_free;
 245         }
 246
 247         if (reply_max) {
 248                 call->reply_max = reply_max;
 249                 call->buffer = kmalloc(reply_max, GFP_NOFS);
 250                 if (!call->buffer)
 251                         goto nomem_free;
 252         }
 253
 254         afs_extract_to_buf(call, call->reply_max);
 255         call->operation_ID = type->op;
 256         init_waitqueue_head(&call->waitq);
 257         return call;
 258
 259 nomem_free:
 260         afs_put_call(call);
 261 nomem_call:
 262         return NULL;
 263 }
 264
 265 /*
 266  * clean up a call with flat buffer
 267  */
 268 void afs_flat_call_destructor(struct afs_call *call)
 269 {
 270         _enter("");
 271
 272         kfree(call->request);
 273         call->request = NULL;
 274         kfree(call->buffer);
 275         call->buffer = NULL;
 276 }
 277
 278 #define AFS_BVEC_MAX 8
 279
 280 /*
 281  * Load the given bvec with the next few pages.
 282  */
 283 static void afs_load_bvec(struct afs_call *call, struct msghdr *msg,
 284                           struct bio_vec *bv, pgoff_t first, pgoff_t last,
 285                           unsigned offset)
 286 {
 287         struct page *pages[AFS_BVEC_MAX];
 288         unsigned int nr, n, i, to, bytes = 0;
 289
 290         nr = min_t(pgoff_t, last - first + 1, AFS_BVEC_MAX);
 291         n = find_get_pages_contig(call->mapping, first, nr, pages);
 292         ASSERTCMP(n, ==, nr);
 293
 294         msg->msg_flags |= MSG_MORE;
 295         for (i = 0; i < nr; i++) {
 296                 to = PAGE_SIZE;
 297                 if (first + i >= last) {
 298                         to = call->last_to;
 299                         msg->msg_flags &= ~MSG_MORE;
 300                 }
 301                 bv[i].bv_page = pages[i];
 302                 bv[i].bv_len = to - offset;
 303                 bv[i].bv_offset = offset;
 304                 bytes += to - offset;
 305                 offset = 0;
 306         }
 307
 308         iov_iter_bvec(&msg->msg_iter, WRITE, bv, nr, bytes);
 309 }
 310
 311 /*
 312  * Advance the AFS call state when the RxRPC call ends the transmit phase.
 313  */
 314 static void afs_notify_end_request_tx(struct sock *sock,
 315                                       struct rxrpc_call *rxcall,
 316                                       unsigned long call_user_ID)
 317 {
 318         struct afs_call *call = (struct afs_call *)call_user_ID;
 319
 320         afs_set_call_state(call, AFS_CALL_CL_REQUESTING, AFS_CALL_CL_AWAIT_REPLY);
 321 }
 322
 323 /*
 324  * attach the data from a bunch of pages on an inode to a call
 325  */
 326 static int afs_send_pages(struct afs_call *call, struct msghdr *msg)
 327 {
 328         struct bio_vec bv[AFS_BVEC_MAX];
 329         unsigned int bytes, nr, loop, offset;
 330         pgoff_t first = call->first, last = call->last;
 331         int ret;
 332
 333         offset = call->first_offset;
 334         call->first_offset = 0;
 335
 336         do {
 337                 afs_load_bvec(call, msg, bv, first, last, offset);
 338                 trace_afs_send_pages(call, msg, first, last, offset);
 339
 340                 offset = 0;
 341                 bytes = msg->msg_iter.count;
 342                 nr = msg->msg_iter.nr_segs;
 343
 344                 ret = rxrpc_kernel_send_data(call->net->socket, call->rxcall, msg,
 345                                              bytes, afs_notify_end_request_tx);
 346                 for (loop = 0; loop < nr; loop++)
 347                         put_page(bv[loop].bv_page);
 348                 if (ret < 0)
 349                         break;
 350
 351                 first += nr;
 352         } while (first <= last);
 353
 354         trace_afs_sent_pages(call, call->first, last, first, ret);
 355         return ret;
 356 }
 357
 358 /*
 359  * Initiate a call and synchronously queue up the parameters for dispatch.  Any
 360  * error is stored into the call struct, which the caller must check for.
 361  */
 362 void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 363 {
 364         struct sockaddr_rxrpc *srx = &ac->alist->addrs[ac->index];
 365         struct rxrpc_call *rxcall;
 366         struct msghdr msg;
 367         struct kvec iov[1];
 368         s64 tx_total_len;
 369         int ret;
 370
 371         _enter(",{%pISp},", &srx->transport);
 372
 373         ASSERT(call->type != NULL);
 374         ASSERT(call->type->name != NULL);
 375
 376         _debug("____MAKE %p{%s,%x} [%d]____",
 377                call, call->type->name, key_serial(call->key),
 378                atomic_read(&call->net->nr_outstanding_calls));
 379
 380         call->addr_ix = ac->index;
 381         call->alist = afs_get_addrlist(ac->alist);
 382
 383         /* Work out the length we're going to transmit.  This is awkward for
 384          * calls such as FS.StoreData where there's an extra injection of data
 385          * after the initial fixed part.
 386          */
 387         tx_total_len = call->request_size;
 388         if (call->send_pages) {
 389                 if (call->last == call->first) {
 390                         tx_total_len += call->last_to - call->first_offset;
 391                 } else {
 392                         /* It looks mathematically like you should be able to
 393                          * combine the following lines with the ones above, but
 394                          * unsigned arithmetic is fun when it wraps...
 395                          */
 396                         tx_total_len += PAGE_SIZE - call->first_offset;
 397                         tx_total_len += call->last_to;
 398                         tx_total_len += (call->last - call->first - 1) * PAGE_SIZE;
 399                 }
 400         }
 401
 402         /* If the call is going to be asynchronous, we need an extra ref for
 403          * the call to hold itself so the caller need not hang on to its ref.
 404          */
 405         if (call->async)
 406                 afs_get_call(call, afs_call_trace_get);
 407
 408         /* create a call */
 409         rxcall = rxrpc_kernel_begin_call(call->net->socket, srx, call->key,
 410                                          (unsigned long)call,
 411                                          tx_total_len, gfp,
 412                                          (call->async ?
 413                                           afs_wake_up_async_call :
 414                                           afs_wake_up_call_waiter),
 415                                          call->upgrade,
 416                                          call->intr,
 417                                          call->debug_id);
 418         if (IS_ERR(rxcall)) {
 419                 ret = PTR_ERR(rxcall);
 420                 call->error = ret;
 421                 goto error_kill_call;
 422         }
 423
 424         call->rxcall = rxcall;
 425
 426         if (call->max_lifespan)
 427                 rxrpc_kernel_set_max_life(call->net->socket, rxcall,
 428                                           call->max_lifespan);
 429
 430         /* send the request */
 431         iov[0].iov_base = call->request;
 432         iov[0].iov_len  = call->request_size;
 433
 434         msg.msg_name            = NULL;
 435         msg.msg_namelen         = 0;
 436         iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size);
 437         msg.msg_control         = NULL;
 438         msg.msg_controllen      = 0;
 439         msg.msg_flags           = MSG_WAITALL | (call->send_pages ? MSG_MORE : 0);
 440
 441         ret = rxrpc_kernel_send_data(call->net->socket, rxcall,
 442                                      &msg, call->request_size,
 443                                      afs_notify_end_request_tx);
 444         if (ret < 0)
 445                 goto error_do_abort;
 446
 447         if (call->send_pages) {
 448                 ret = afs_send_pages(call, &msg);
 449                 if (ret < 0)
 450                         goto error_do_abort;
 451         }
 452
 453         /* Note that at this point, we may have received the reply or an abort
 454          * - and an asynchronous call may already have completed.
 455          *
 456          * afs_wait_for_call_to_complete(call, ac)
 457          * must be called to synchronously clean up.
 458          */
 459         return;
 460
 461 error_do_abort:
 462         if (ret != -ECONNABORTED) {
 463                 rxrpc_kernel_abort_call(call->net->socket, rxcall,
 464                                         RX_USER_ABORT, ret, "KSD");
 465         } else {
 466                 iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0);
 467                 rxrpc_kernel_recv_data(call->net->socket, rxcall,
 468                                        &msg.msg_iter, false,
 469                                        &call->abort_code, &call->service_id);
 470                 ac->abort_code = call->abort_code;
 471                 ac->responded = true;
 472         }
 473         call->error = ret;
 474         trace_afs_call_done(call);
 475 error_kill_call:
 476         if (call->type->done)
 477                 call->type->done(call);
 478
 479         /* We need to dispose of the extra ref we grabbed for an async call.
 480          * The call, however, might be queued on afs_async_calls and we need to
 481          * make sure we don't get any more notifications that might requeue it.
 482          */
 483         if (call->rxcall) {
 484                 rxrpc_kernel_end_call(call->net->socket, call->rxcall);
 485                 call->rxcall = NULL;
 486         }
 487         if (call->async) {
 488                 if (cancel_work_sync(&call->async_work))
 489                         afs_put_call(call);
 490                 afs_put_call(call);
 491         }
 492
 493         ac->error = ret;
 494         call->state = AFS_CALL_COMPLETE;
 495         _leave(" = %d", ret);
 496 }
 497
 498 /*
 499  * deliver messages to a call
 500  */
 501 static void afs_deliver_to_call(struct afs_call *call)
 502 {
 503         enum afs_call_state state;
 504         u32 abort_code, remote_abort = 0;
 505         int ret;
 506
 507         _enter("%s", call->type->name);
 508
 509         while (state = READ_ONCE(call->state),
 510                state == AFS_CALL_CL_AWAIT_REPLY ||
 511                state == AFS_CALL_SV_AWAIT_OP_ID ||
 512                state == AFS_CALL_SV_AWAIT_REQUEST ||
 513                state == AFS_CALL_SV_AWAIT_ACK
 514                ) {
 515                 if (state == AFS_CALL_SV_AWAIT_ACK) {
 516                         iov_iter_kvec(&call->iter, READ, NULL, 0, 0);
 517                         ret = rxrpc_kernel_recv_data(call->net->socket,
 518                                                      call->rxcall, &call->iter,
 519                                                      false, &remote_abort,
 520                                                      &call->service_id);
 521                         trace_afs_receive_data(call, &call->iter, false, ret);
 522
 523                         if (ret == -EINPROGRESS || ret == -EAGAIN)
 524                                 return;
 525                         if (ret < 0 || ret == 1) {
 526                                 if (ret == 1)
 527                                         ret = 0;
 528                                 goto call_complete;
 529                         }
 530                         return;
 531                 }
 532
 533                 if (!call->have_reply_time &&
 534                     rxrpc_kernel_get_reply_time(call->net->socket,
 535                                                 call->rxcall,
 536                                                 &call->reply_time))
 537                         call->have_reply_time = true;
 538
 539                 ret = call->type->deliver(call);
 540                 state = READ_ONCE(call->state);
 541                 switch (ret) {
 542                 case 0:
 543                         afs_queue_call_work(call);
 544                         if (state == AFS_CALL_CL_PROC_REPLY) {
 545                                 if (call->cbi)
 546                                         set_bit(AFS_SERVER_FL_MAY_HAVE_CB,
 547                                                 &call->cbi->server->flags);
 548                                 goto call_complete;
 549                         }
 550                         ASSERTCMP(state, >, AFS_CALL_CL_PROC_REPLY);
 551                         goto done;
 552                 case -EINPROGRESS:
 553                 case -EAGAIN:
 554                         goto out;
 555                 case -ECONNABORTED:
 556                         ASSERTCMP(state, ==, AFS_CALL_COMPLETE);
 557                         goto done;
 558                 case -ENOTSUPP:
 559                         abort_code = RXGEN_OPCODE;
 560                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 561                                                 abort_code, ret, "KIV");
 562                         goto local_abort;
 563                 case -EIO:
 564                         pr_err("kAFS: Call %u in bad state %u\n",
 565                                call->debug_id, state);
 566                         /* Fall through */
 567                 case -ENODATA:
 568                 case -EBADMSG:
 569                 case -EMSGSIZE:
 570                         abort_code = RXGEN_CC_UNMARSHAL;
 571                         if (state != AFS_CALL_CL_AWAIT_REPLY)
 572                                 abort_code = RXGEN_SS_UNMARSHAL;
 573                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 574                                                 abort_code, ret, "KUM");
 575                         goto local_abort;
 576                 default:
 577                         abort_code = RX_USER_ABORT;
 578                         rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 579                                                 abort_code, ret, "KER");
 580                         goto local_abort;
 581                 }
 582         }
 583
 584 done:
 585         if (call->type->done)
 586                 call->type->done(call);
 587         if (state == AFS_CALL_COMPLETE && call->incoming)
 588                 afs_put_call(call);
 589 out:
 590         _leave("");
 591         return;
 592
 593 local_abort:
 594         abort_code = 0;
 595 call_complete:
 596         afs_set_call_complete(call, ret, remote_abort);
 597         state = AFS_CALL_COMPLETE;
 598         goto done;
 599 }
 600
 601 /*
 602  * Wait synchronously for a call to complete and clean up the call struct.
 603  */
 604 long afs_wait_for_call_to_complete(struct afs_call *call,
 605                                    struct afs_addr_cursor *ac)
 606 {
 607         signed long rtt2, timeout;
 608         long ret;
 609         bool stalled = false;
 610         u64 rtt;
 611         u32 life, last_life;
 612         bool rxrpc_complete = false;
 613
 614         DECLARE_WAITQUEUE(myself, current);
 615
 616         _enter("");
 617
 618         ret = call->error;
 619         if (ret < 0)
 620                 goto out;
 621
 622         rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
 623         rtt2 = nsecs_to_jiffies64(rtt) * 2;
 624         if (rtt2 < 2)
 625                 rtt2 = 2;
 626
 627         timeout = rtt2;
 628         rxrpc_kernel_check_life(call->net->socket, call->rxcall, &last_life);
 629
 630         add_wait_queue(&call->waitq, &myself);
 631         for (;;) {
 632                 set_current_state(TASK_UNINTERRUPTIBLE);
 633
 634                 /* deliver any messages that are in the queue */
 635                 if (!afs_check_call_state(call, AFS_CALL_COMPLETE) &&
 636                     call->need_attention) {
 637                         call->need_attention = false;
 638                         __set_current_state(TASK_RUNNING);
 639                         afs_deliver_to_call(call);
 640                         continue;
 641                 }
 642
 643                 if (afs_check_call_state(call, AFS_CALL_COMPLETE))
 644                         break;
 645
 646                 if (!rxrpc_kernel_check_life(call->net->socket, call->rxcall, &life)) {
 647                         /* rxrpc terminated the call. */
 648                         rxrpc_complete = true;
 649                         break;
 650                 }
 651
 652                 if (call->intr && timeout == 0 &&
 653                     life == last_life && signal_pending(current)) {
 654                         if (stalled)
 655                                 break;
 656                         __set_current_state(TASK_RUNNING);
 657                         rxrpc_kernel_probe_life(call->net->socket, call->rxcall);
 658                         timeout = rtt2;
 659                         stalled = true;
 660                         continue;
 661                 }
 662
 663                 if (life != last_life) {
 664                         timeout = rtt2;
 665                         last_life = life;
 666                         stalled = false;
 667                 }
 668
 669                 timeout = schedule_timeout(timeout);
 670         }
 671
 672         remove_wait_queue(&call->waitq, &myself);
 673         __set_current_state(TASK_RUNNING);
 674
 675         if (!afs_check_call_state(call, AFS_CALL_COMPLETE)) {
 676                 if (rxrpc_complete) {
 677                         afs_set_call_complete(call, call->error, call->abort_code);
 678                 } else {
 679                         /* Kill off the call if it's still live. */
 680                         _debug("call interrupted");
 681                         if (rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
 682                                                     RX_USER_ABORT, -EINTR, "KWI"))
 683                                 afs_set_call_complete(call, -EINTR, 0);
 684                 }
 685         }
 686
 687         spin_lock_bh(&call->state_lock);
 688         ac->abort_code = call->abort_code;
 689         ac->error = call->error;
 690         spin_unlock_bh(&call->state_lock);
 691
 692         ret = ac->error;
 693         switch (ret) {
 694         case 0:
 695                 ret = call->ret0;
 696                 call->ret0 = 0;
 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 }