fs/afs/cmservice.c

   1 /* AFS Cache Manager Service
   2  *
   3  * Copyright (C) 2002 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/module.h>
  13 #include <linux/init.h>
  14 #include <linux/slab.h>
  15 #include <linux/sched.h>
  16 #include <linux/ip.h>
  17 #include "internal.h"
  18 #include "afs_cm.h"
  19 #include "protocol_yfs.h"
  20
  21 static int afs_deliver_cb_init_call_back_state(struct afs_call *);
  22 static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
  23 static int afs_deliver_cb_probe(struct afs_call *);
  24 static int afs_deliver_cb_callback(struct afs_call *);
  25 static int afs_deliver_cb_probe_uuid(struct afs_call *);
  26 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
  27 static void afs_cm_destructor(struct afs_call *);
  28 static void SRXAFSCB_CallBack(struct work_struct *);
  29 static void SRXAFSCB_InitCallBackState(struct work_struct *);
  30 static void SRXAFSCB_Probe(struct work_struct *);
  31 static void SRXAFSCB_ProbeUuid(struct work_struct *);
  32 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
  33
  34 static int afs_deliver_yfs_cb_callback(struct afs_call *);
  35
  36 #define CM_NAME(name) \
  37         char afs_SRXCB##name##_name[] __tracepoint_string =     \
  38                 "CB." #name
  39
  40 /*
  41  * CB.CallBack operation type
  42  */
  43 static CM_NAME(CallBack);
  44 static const struct afs_call_type afs_SRXCBCallBack = {
  45         .name           = afs_SRXCBCallBack_name,
  46         .deliver        = afs_deliver_cb_callback,
  47         .destructor     = afs_cm_destructor,
  48         .work           = SRXAFSCB_CallBack,
  49 };
  50
  51 /*
  52  * CB.InitCallBackState operation type
  53  */
  54 static CM_NAME(InitCallBackState);
  55 static const struct afs_call_type afs_SRXCBInitCallBackState = {
  56         .name           = afs_SRXCBInitCallBackState_name,
  57         .deliver        = afs_deliver_cb_init_call_back_state,
  58         .destructor     = afs_cm_destructor,
  59         .work           = SRXAFSCB_InitCallBackState,
  60 };
  61
  62 /*
  63  * CB.InitCallBackState3 operation type
  64  */
  65 static CM_NAME(InitCallBackState3);
  66 static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
  67         .name           = afs_SRXCBInitCallBackState3_name,
  68         .deliver        = afs_deliver_cb_init_call_back_state3,
  69         .destructor     = afs_cm_destructor,
  70         .work           = SRXAFSCB_InitCallBackState,
  71 };
  72
  73 /*
  74  * CB.Probe operation type
  75  */
  76 static CM_NAME(Probe);
  77 static const struct afs_call_type afs_SRXCBProbe = {
  78         .name           = afs_SRXCBProbe_name,
  79         .deliver        = afs_deliver_cb_probe,
  80         .destructor     = afs_cm_destructor,
  81         .work           = SRXAFSCB_Probe,
  82 };
  83
  84 /*
  85  * CB.ProbeUuid operation type
  86  */
  87 static CM_NAME(ProbeUuid);
  88 static const struct afs_call_type afs_SRXCBProbeUuid = {
  89         .name           = afs_SRXCBProbeUuid_name,
  90         .deliver        = afs_deliver_cb_probe_uuid,
  91         .destructor     = afs_cm_destructor,
  92         .work           = SRXAFSCB_ProbeUuid,
  93 };
  94
  95 /*
  96  * CB.TellMeAboutYourself operation type
  97  */
  98 static CM_NAME(TellMeAboutYourself);
  99 static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
 100         .name           = afs_SRXCBTellMeAboutYourself_name,
 101         .deliver        = afs_deliver_cb_tell_me_about_yourself,
 102         .destructor     = afs_cm_destructor,
 103         .work           = SRXAFSCB_TellMeAboutYourself,
 104 };
 105
 106 /*
 107  * YFS CB.CallBack operation type
 108  */
 109 static CM_NAME(YFS_CallBack);
 110 static const struct afs_call_type afs_SRXYFSCB_CallBack = {
 111         .name           = afs_SRXCBYFS_CallBack_name,
 112         .deliver        = afs_deliver_yfs_cb_callback,
 113         .destructor     = afs_cm_destructor,
 114         .work           = SRXAFSCB_CallBack,
 115 };
 116
 117 /*
 118  * route an incoming cache manager call
 119  * - return T if supported, F if not
 120  */
 121 bool afs_cm_incoming_call(struct afs_call *call)
 122 {
 123         _enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
 124
 125         call->epoch = rxrpc_kernel_get_epoch(call->net->socket, call->rxcall);
 126
 127         switch (call->operation_ID) {
 128         case CBCallBack:
 129                 call->type = &afs_SRXCBCallBack;
 130                 return true;
 131         case CBInitCallBackState:
 132                 call->type = &afs_SRXCBInitCallBackState;
 133                 return true;
 134         case CBInitCallBackState3:
 135                 call->type = &afs_SRXCBInitCallBackState3;
 136                 return true;
 137         case CBProbe:
 138                 call->type = &afs_SRXCBProbe;
 139                 return true;
 140         case CBProbeUuid:
 141                 call->type = &afs_SRXCBProbeUuid;
 142                 return true;
 143         case CBTellMeAboutYourself:
 144                 call->type = &afs_SRXCBTellMeAboutYourself;
 145                 return true;
 146         case YFSCBCallBack:
 147                 if (call->service_id != YFS_CM_SERVICE)
 148                         return false;
 149                 call->type = &afs_SRXYFSCB_CallBack;
 150                 return true;
 151         default:
 152                 return false;
 153         }
 154 }
 155
 156 /*
 157  * Record a probe to the cache manager from a server.
 158  */
 159 static int afs_record_cm_probe(struct afs_call *call, struct afs_server *server)
 160 {
 161         _enter("");
 162
 163         if (test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags) &&
 164             !test_bit(AFS_SERVER_FL_PROBING, &server->flags)) {
 165                 if (server->cm_epoch == call->epoch)
 166                         return 0;
 167
 168                 if (!server->probe.said_rebooted) {
 169                         pr_notice("kAFS: FS rebooted %pU\n", &server->uuid);
 170                         server->probe.said_rebooted = true;
 171                 }
 172         }
 173
 174         spin_lock(&server->probe_lock);
 175
 176         if (!test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags)) {
 177                 server->cm_epoch = call->epoch;
 178                 server->probe.cm_epoch = call->epoch;
 179                 goto out;
 180         }
 181
 182         if (server->probe.cm_probed &&
 183             call->epoch != server->probe.cm_epoch &&
 184             !server->probe.said_inconsistent) {
 185                 pr_notice("kAFS: FS endpoints inconsistent %pU\n",
 186                           &server->uuid);
 187                 server->probe.said_inconsistent = true;
 188         }
 189
 190         if (!server->probe.cm_probed || call->epoch == server->cm_epoch)
 191                 server->probe.cm_epoch = server->cm_epoch;
 192
 193 out:
 194         server->probe.cm_probed = true;
 195         spin_unlock(&server->probe_lock);
 196         return 0;
 197 }
 198
 199 /*
 200  * Find the server record by peer address and record a probe to the cache
 201  * manager from a server.
 202  */
 203 static int afs_find_cm_server_by_peer(struct afs_call *call)
 204 {
 205         struct sockaddr_rxrpc srx;
 206         struct afs_server *server;
 207
 208         rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
 209
 210         server = afs_find_server(call->net, &srx);
 211         if (!server) {
 212                 trace_afs_cm_no_server(call, &srx);
 213                 return 0;
 214         }
 215
 216         call->cm_server = server;
 217         return afs_record_cm_probe(call, server);
 218 }
 219
 220 /*
 221  * Find the server record by server UUID and record a probe to the cache
 222  * manager from a server.
 223  */
 224 static int afs_find_cm_server_by_uuid(struct afs_call *call,
 225                                       struct afs_uuid *uuid)
 226 {
 227         struct afs_server *server;
 228
 229         rcu_read_lock();
 230         server = afs_find_server_by_uuid(call->net, call->request);
 231         rcu_read_unlock();
 232         if (!server) {
 233                 trace_afs_cm_no_server_u(call, call->request);
 234                 return 0;
 235         }
 236
 237         call->cm_server = server;
 238         return afs_record_cm_probe(call, server);
 239 }
 240
 241 /*
 242  * Clean up a cache manager call.
 243  */
 244 static void afs_cm_destructor(struct afs_call *call)
 245 {
 246         kfree(call->buffer);
 247         call->buffer = NULL;
 248 }
 249
 250 /*
 251  * The server supplied a list of callbacks that it wanted to break.
 252  */
 253 static void SRXAFSCB_CallBack(struct work_struct *work)
 254 {
 255         struct afs_call *call = container_of(work, struct afs_call, work);
 256
 257         _enter("");
 258
 259         /* We need to break the callbacks before sending the reply as the
 260          * server holds up change visibility till it receives our reply so as
 261          * to maintain cache coherency.
 262          */
 263         if (call->cm_server)
 264                 afs_break_callbacks(call->cm_server, call->count, call->request);
 265
 266         afs_send_empty_reply(call);
 267         afs_put_call(call);
 268         _leave("");
 269 }
 270
 271 /*
 272  * deliver request data to a CB.CallBack call
 273  */
 274 static int afs_deliver_cb_callback(struct afs_call *call)
 275 {
 276         struct afs_callback_break *cb;
 277         __be32 *bp;
 278         int ret, loop;
 279
 280         _enter("{%u}", call->unmarshall);
 281
 282         switch (call->unmarshall) {
 283         case 0:
 284                 afs_extract_to_tmp(call);
 285                 call->unmarshall++;
 286
 287                 /* extract the FID array and its count in two steps */
 288                 /* fall through */
 289         case 1:
 290                 _debug("extract FID count");
 291                 ret = afs_extract_data(call, true);
 292                 if (ret < 0)
 293                         return ret;
 294
 295                 call->count = ntohl(call->tmp);
 296                 _debug("FID count: %u", call->count);
 297                 if (call->count > AFSCBMAX)
 298                         return afs_protocol_error(call, -EBADMSG,
 299                                                   afs_eproto_cb_fid_count);
 300
 301                 call->buffer = kmalloc(array3_size(call->count, 3, 4),
 302                                        GFP_KERNEL);
 303                 if (!call->buffer)
 304                         return -ENOMEM;
 305                 afs_extract_to_buf(call, call->count * 3 * 4);
 306                 call->unmarshall++;
 307
 308                 /* Fall through */
 309         case 2:
 310                 _debug("extract FID array");
 311                 ret = afs_extract_data(call, true);
 312                 if (ret < 0)
 313                         return ret;
 314
 315                 _debug("unmarshall FID array");
 316                 call->request = kcalloc(call->count,
 317                                         sizeof(struct afs_callback_break),
 318                                         GFP_KERNEL);
 319                 if (!call->request)
 320                         return -ENOMEM;
 321
 322                 cb = call->request;
 323                 bp = call->buffer;
 324                 for (loop = call->count; loop > 0; loop--, cb++) {
 325                         cb->fid.vid     = ntohl(*bp++);
 326                         cb->fid.vnode   = ntohl(*bp++);
 327                         cb->fid.unique  = ntohl(*bp++);
 328                 }
 329
 330                 afs_extract_to_tmp(call);
 331                 call->unmarshall++;
 332
 333                 /* extract the callback array and its count in two steps */
 334                 /* fall through */
 335         case 3:
 336                 _debug("extract CB count");
 337                 ret = afs_extract_data(call, true);
 338                 if (ret < 0)
 339                         return ret;
 340
 341                 call->count2 = ntohl(call->tmp);
 342                 _debug("CB count: %u", call->count2);
 343                 if (call->count2 != call->count && call->count2 != 0)
 344                         return afs_protocol_error(call, -EBADMSG,
 345                                                   afs_eproto_cb_count);
 346                 call->_iter = &call->iter;
 347                 iov_iter_discard(&call->iter, READ, call->count2 * 3 * 4);
 348                 call->unmarshall++;
 349
 350                 /* Fall through */
 351         case 4:
 352                 _debug("extract discard %zu/%u",
 353                        iov_iter_count(&call->iter), call->count2 * 3 * 4);
 354
 355                 ret = afs_extract_data(call, false);
 356                 if (ret < 0)
 357                         return ret;
 358
 359                 call->unmarshall++;
 360         case 5:
 361                 break;
 362         }
 363
 364         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 365                 return afs_io_error(call, afs_io_error_cm_reply);
 366
 367         /* we'll need the file server record as that tells us which set of
 368          * vnodes to operate upon */
 369         return afs_find_cm_server_by_peer(call);
 370 }
 371
 372 /*
 373  * allow the fileserver to request callback state (re-)initialisation
 374  */
 375 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
 376 {
 377         struct afs_call *call = container_of(work, struct afs_call, work);
 378
 379         _enter("{%p}", call->cm_server);
 380
 381         if (call->cm_server)
 382                 afs_init_callback_state(call->cm_server);
 383         afs_send_empty_reply(call);
 384         afs_put_call(call);
 385         _leave("");
 386 }
 387
 388 /*
 389  * deliver request data to a CB.InitCallBackState call
 390  */
 391 static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
 392 {
 393         int ret;
 394
 395         _enter("");
 396
 397         afs_extract_discard(call, 0);
 398         ret = afs_extract_data(call, false);
 399         if (ret < 0)
 400                 return ret;
 401
 402         /* we'll need the file server record as that tells us which set of
 403          * vnodes to operate upon */
 404         return afs_find_cm_server_by_peer(call);
 405 }
 406
 407 /*
 408  * deliver request data to a CB.InitCallBackState3 call
 409  */
 410 static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
 411 {
 412         struct afs_uuid *r;
 413         unsigned loop;
 414         __be32 *b;
 415         int ret;
 416
 417         _enter("");
 418
 419         _enter("{%u}", call->unmarshall);
 420
 421         switch (call->unmarshall) {
 422         case 0:
 423                 call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
 424                 if (!call->buffer)
 425                         return -ENOMEM;
 426                 afs_extract_to_buf(call, 11 * sizeof(__be32));
 427                 call->unmarshall++;
 428
 429                 /* Fall through */
 430         case 1:
 431                 _debug("extract UUID");
 432                 ret = afs_extract_data(call, false);
 433                 switch (ret) {
 434                 case 0:         break;
 435                 case -EAGAIN:   return 0;
 436                 default:        return ret;
 437                 }
 438
 439                 _debug("unmarshall UUID");
 440                 call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
 441                 if (!call->request)
 442                         return -ENOMEM;
 443
 444                 b = call->buffer;
 445                 r = call->request;
 446                 r->time_low                     = b[0];
 447                 r->time_mid                     = htons(ntohl(b[1]));
 448                 r->time_hi_and_version          = htons(ntohl(b[2]));
 449                 r->clock_seq_hi_and_reserved    = ntohl(b[3]);
 450                 r->clock_seq_low                = ntohl(b[4]);
 451
 452                 for (loop = 0; loop < 6; loop++)
 453                         r->node[loop] = ntohl(b[loop + 5]);
 454
 455                 call->unmarshall++;
 456
 457         case 2:
 458                 break;
 459         }
 460
 461         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 462                 return afs_io_error(call, afs_io_error_cm_reply);
 463
 464         /* we'll need the file server record as that tells us which set of
 465          * vnodes to operate upon */
 466         return afs_find_cm_server_by_uuid(call, call->request);
 467 }
 468
 469 /*
 470  * allow the fileserver to see if the cache manager is still alive
 471  */
 472 static void SRXAFSCB_Probe(struct work_struct *work)
 473 {
 474         struct afs_call *call = container_of(work, struct afs_call, work);
 475
 476         _enter("");
 477         afs_send_empty_reply(call);
 478         afs_put_call(call);
 479         _leave("");
 480 }
 481
 482 /*
 483  * deliver request data to a CB.Probe call
 484  */
 485 static int afs_deliver_cb_probe(struct afs_call *call)
 486 {
 487         int ret;
 488
 489         _enter("");
 490
 491         afs_extract_discard(call, 0);
 492         ret = afs_extract_data(call, false);
 493         if (ret < 0)
 494                 return ret;
 495
 496         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 497                 return afs_io_error(call, afs_io_error_cm_reply);
 498         return afs_find_cm_server_by_peer(call);
 499 }
 500
 501 /*
 502  * allow the fileserver to quickly find out if the fileserver has been rebooted
 503  */
 504 static void SRXAFSCB_ProbeUuid(struct work_struct *work)
 505 {
 506         struct afs_call *call = container_of(work, struct afs_call, work);
 507         struct afs_uuid *r = call->request;
 508
 509         struct {
 510                 __be32  match;
 511         } reply;
 512
 513         _enter("");
 514
 515         if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
 516                 reply.match = htonl(0);
 517         else
 518                 reply.match = htonl(1);
 519
 520         afs_send_simple_reply(call, &reply, sizeof(reply));
 521         afs_put_call(call);
 522         _leave("");
 523 }
 524
 525 /*
 526  * deliver request data to a CB.ProbeUuid call
 527  */
 528 static int afs_deliver_cb_probe_uuid(struct afs_call *call)
 529 {
 530         struct afs_uuid *r;
 531         unsigned loop;
 532         __be32 *b;
 533         int ret;
 534
 535         _enter("{%u}", call->unmarshall);
 536
 537         switch (call->unmarshall) {
 538         case 0:
 539                 call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
 540                 if (!call->buffer)
 541                         return -ENOMEM;
 542                 afs_extract_to_buf(call, 11 * sizeof(__be32));
 543                 call->unmarshall++;
 544
 545                 /* Fall through */
 546         case 1:
 547                 _debug("extract UUID");
 548                 ret = afs_extract_data(call, false);
 549                 switch (ret) {
 550                 case 0:         break;
 551                 case -EAGAIN:   return 0;
 552                 default:        return ret;
 553                 }
 554
 555                 _debug("unmarshall UUID");
 556                 call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
 557                 if (!call->request)
 558                         return -ENOMEM;
 559
 560                 b = call->buffer;
 561                 r = call->request;
 562                 r->time_low                     = b[0];
 563                 r->time_mid                     = htons(ntohl(b[1]));
 564                 r->time_hi_and_version          = htons(ntohl(b[2]));
 565                 r->clock_seq_hi_and_reserved    = ntohl(b[3]);
 566                 r->clock_seq_low                = ntohl(b[4]);
 567
 568                 for (loop = 0; loop < 6; loop++)
 569                         r->node[loop] = ntohl(b[loop + 5]);
 570
 571                 call->unmarshall++;
 572
 573         case 2:
 574                 break;
 575         }
 576
 577         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 578                 return afs_io_error(call, afs_io_error_cm_reply);
 579         return afs_find_cm_server_by_uuid(call, call->request);
 580 }
 581
 582 /*
 583  * allow the fileserver to ask about the cache manager's capabilities
 584  */
 585 static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
 586 {
 587         struct afs_interface *ifs;
 588         struct afs_call *call = container_of(work, struct afs_call, work);
 589         int loop, nifs;
 590
 591         struct {
 592                 struct /* InterfaceAddr */ {
 593                         __be32 nifs;
 594                         __be32 uuid[11];
 595                         __be32 ifaddr[32];
 596                         __be32 netmask[32];
 597                         __be32 mtu[32];
 598                 } ia;
 599                 struct /* Capabilities */ {
 600                         __be32 capcount;
 601                         __be32 caps[1];
 602                 } cap;
 603         } reply;
 604
 605         _enter("");
 606
 607         nifs = 0;
 608         ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
 609         if (ifs) {
 610                 nifs = afs_get_ipv4_interfaces(call->net, ifs, 32, false);
 611                 if (nifs < 0) {
 612                         kfree(ifs);
 613                         ifs = NULL;
 614                         nifs = 0;
 615                 }
 616         }
 617
 618         memset(&reply, 0, sizeof(reply));
 619         reply.ia.nifs = htonl(nifs);
 620
 621         reply.ia.uuid[0] = call->net->uuid.time_low;
 622         reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
 623         reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
 624         reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
 625         reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
 626         for (loop = 0; loop < 6; loop++)
 627                 reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
 628
 629         if (ifs) {
 630                 for (loop = 0; loop < nifs; loop++) {
 631                         reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
 632                         reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
 633                         reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
 634                 }
 635                 kfree(ifs);
 636         }
 637
 638         reply.cap.capcount = htonl(1);
 639         reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
 640         afs_send_simple_reply(call, &reply, sizeof(reply));
 641         afs_put_call(call);
 642         _leave("");
 643 }
 644
 645 /*
 646  * deliver request data to a CB.TellMeAboutYourself call
 647  */
 648 static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
 649 {
 650         int ret;
 651
 652         _enter("");
 653
 654         afs_extract_discard(call, 0);
 655         ret = afs_extract_data(call, false);
 656         if (ret < 0)
 657                 return ret;
 658
 659         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 660                 return afs_io_error(call, afs_io_error_cm_reply);
 661         return afs_find_cm_server_by_peer(call);
 662 }
 663
 664 /*
 665  * deliver request data to a YFS CB.CallBack call
 666  */
 667 static int afs_deliver_yfs_cb_callback(struct afs_call *call)
 668 {
 669         struct afs_callback_break *cb;
 670         struct yfs_xdr_YFSFid *bp;
 671         size_t size;
 672         int ret, loop;
 673
 674         _enter("{%u}", call->unmarshall);
 675
 676         switch (call->unmarshall) {
 677         case 0:
 678                 afs_extract_to_tmp(call);
 679                 call->unmarshall++;
 680
 681                 /* extract the FID array and its count in two steps */
 682                 /* Fall through */
 683         case 1:
 684                 _debug("extract FID count");
 685                 ret = afs_extract_data(call, true);
 686                 if (ret < 0)
 687                         return ret;
 688
 689                 call->count = ntohl(call->tmp);
 690                 _debug("FID count: %u", call->count);
 691                 if (call->count > YFSCBMAX)
 692                         return afs_protocol_error(call, -EBADMSG,
 693                                                   afs_eproto_cb_fid_count);
 694
 695                 size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
 696                 call->buffer = kmalloc(size, GFP_KERNEL);
 697                 if (!call->buffer)
 698                         return -ENOMEM;
 699                 afs_extract_to_buf(call, size);
 700                 call->unmarshall++;
 701
 702                 /* Fall through */
 703         case 2:
 704                 _debug("extract FID array");
 705                 ret = afs_extract_data(call, false);
 706                 if (ret < 0)
 707                         return ret;
 708
 709                 _debug("unmarshall FID array");
 710                 call->request = kcalloc(call->count,
 711                                         sizeof(struct afs_callback_break),
 712                                         GFP_KERNEL);
 713                 if (!call->request)
 714                         return -ENOMEM;
 715
 716                 cb = call->request;
 717                 bp = call->buffer;
 718                 for (loop = call->count; loop > 0; loop--, cb++) {
 719                         cb->fid.vid     = xdr_to_u64(bp->volume);
 720                         cb->fid.vnode   = xdr_to_u64(bp->vnode.lo);
 721                         cb->fid.vnode_hi = ntohl(bp->vnode.hi);
 722                         cb->fid.unique  = ntohl(bp->vnode.unique);
 723                         bp++;
 724                 }
 725
 726                 afs_extract_to_tmp(call);
 727                 call->unmarshall++;
 728
 729         case 3:
 730                 break;
 731         }
 732
 733         if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
 734                 return afs_io_error(call, afs_io_error_cm_reply);
 735
 736         /* We'll need the file server record as that tells us which set of
 737          * vnodes to operate upon.
 738          */
 739         return afs_find_cm_server_by_peer(call);
 740 }