LXR linux/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
  20#if 0
  21struct workqueue_struct *afs_cm_workqueue;
  22#endif  /*  0  */
  23
  24static int afs_deliver_cb_init_call_back_state(struct afs_call *,
  25                                               struct sk_buff *, bool);
  26static int afs_deliver_cb_init_call_back_state3(struct afs_call *,
  27                                                struct sk_buff *, bool);
  28static int afs_deliver_cb_probe(struct afs_call *, struct sk_buff *, bool);
  29static int afs_deliver_cb_callback(struct afs_call *, struct sk_buff *, bool);
  30static int afs_deliver_cb_probe_uuid(struct afs_call *, struct sk_buff *, bool);
  31static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *,
  32                                                 struct sk_buff *, bool);
  33static void afs_cm_destructor(struct afs_call *);
  34
  35/*
  36 * CB.CallBack operation type
  37 */
  38static const struct afs_call_type afs_SRXCBCallBack = {
  39        .name           = "CB.CallBack",
  40        .deliver        = afs_deliver_cb_callback,
  41        .abort_to_error = afs_abort_to_error,
  42        .destructor     = afs_cm_destructor,
  43};
  44
  45/*
  46 * CB.InitCallBackState operation type
  47 */
  48static const struct afs_call_type afs_SRXCBInitCallBackState = {
  49        .name           = "CB.InitCallBackState",
  50        .deliver        = afs_deliver_cb_init_call_back_state,
  51        .abort_to_error = afs_abort_to_error,
  52        .destructor     = afs_cm_destructor,
  53};
  54
  55/*
  56 * CB.InitCallBackState3 operation type
  57 */
  58static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
  59        .name           = "CB.InitCallBackState3",
  60        .deliver        = afs_deliver_cb_init_call_back_state3,
  61        .abort_to_error = afs_abort_to_error,
  62        .destructor     = afs_cm_destructor,
  63};
  64
  65/*
  66 * CB.Probe operation type
  67 */
  68static const struct afs_call_type afs_SRXCBProbe = {
  69        .name           = "CB.Probe",
  70        .deliver        = afs_deliver_cb_probe,
  71        .abort_to_error = afs_abort_to_error,
  72        .destructor     = afs_cm_destructor,
  73};
  74
  75/*
  76 * CB.ProbeUuid operation type
  77 */
  78static const struct afs_call_type afs_SRXCBProbeUuid = {
  79        .name           = "CB.ProbeUuid",
  80        .deliver        = afs_deliver_cb_probe_uuid,
  81        .abort_to_error = afs_abort_to_error,
  82        .destructor     = afs_cm_destructor,
  83};
  84
  85/*
  86 * CB.TellMeAboutYourself operation type
  87 */
  88static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
  89        .name           = "CB.TellMeAboutYourself",
  90        .deliver        = afs_deliver_cb_tell_me_about_yourself,
  91        .abort_to_error = afs_abort_to_error,
  92        .destructor     = afs_cm_destructor,
  93};
  94
  95/*
  96 * route an incoming cache manager call
  97 * - return T if supported, F if not
  98 */
  99bool afs_cm_incoming_call(struct afs_call *call)
 100{
 101        u32 operation_id = ntohl(call->operation_ID);
 102
 103        _enter("{CB.OP %u}", operation_id);
 104
 105        switch (operation_id) {
 106        case CBCallBack:
 107                call->type = &afs_SRXCBCallBack;
 108                return true;
 109        case CBInitCallBackState:
 110                call->type = &afs_SRXCBInitCallBackState;
 111                return true;
 112        case CBInitCallBackState3:
 113                call->type = &afs_SRXCBInitCallBackState3;
 114                return true;
 115        case CBProbe:
 116                call->type = &afs_SRXCBProbe;
 117                return true;
 118        case CBTellMeAboutYourself:
 119                call->type = &afs_SRXCBTellMeAboutYourself;
 120                return true;
 121        default:
 122                return false;
 123        }
 124}
 125
 126/*
 127 * clean up a cache manager call
 128 */
 129static void afs_cm_destructor(struct afs_call *call)
 130{
 131        _enter("");
 132
 133        /* Break the callbacks here so that we do it after the final ACK is
 134         * received.  The step number here must match the final number in
 135         * afs_deliver_cb_callback().
 136         */
 137        if (call->unmarshall == 6) {
 138                ASSERT(call->server && call->count && call->request);
 139                afs_break_callbacks(call->server, call->count, call->request);
 140        }
 141
 142        afs_put_server(call->server);
 143        call->server = NULL;
 144        kfree(call->buffer);
 145        call->buffer = NULL;
 146}
 147
 148/*
 149 * allow the fileserver to see if the cache manager is still alive
 150 */
 151static void SRXAFSCB_CallBack(struct work_struct *work)
 152{
 153        struct afs_call *call = container_of(work, struct afs_call, work);
 154
 155        _enter("");
 156
 157        /* be sure to send the reply *before* attempting to spam the AFS server
 158         * with FSFetchStatus requests on the vnodes with broken callbacks lest
 159         * the AFS server get into a vicious cycle of trying to break further
 160         * callbacks because it hadn't received completion of the CBCallBack op
 161         * yet */
 162        afs_send_empty_reply(call);
 163
 164        afs_break_callbacks(call->server, call->count, call->request);
 165        _leave("");
 166}
 167
 168/*
 169 * deliver request data to a CB.CallBack call
 170 */
 171static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
 172                                   bool last)
 173{
 174        struct afs_callback *cb;
 175        struct afs_server *server;
 176        struct in_addr addr;
 177        __be32 *bp;
 178        u32 tmp;
 179        int ret, loop;
 180
 181        _enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
 182
 183        switch (call->unmarshall) {
 184        case 0:
 185                call->offset = 0;
 186                call->unmarshall++;
 187
 188                /* extract the FID array and its count in two steps */
 189        case 1:
 190                _debug("extract FID count");
 191                ret = afs_extract_data(call, skb, last, &call->tmp, 4);
 192                switch (ret) {
 193                case 0:         break;
 194                case -EAGAIN:   return 0;
 195                default:        return ret;
 196                }
 197
 198                call->count = ntohl(call->tmp);
 199                _debug("FID count: %u", call->count);
 200                if (call->count > AFSCBMAX)
 201                        return -EBADMSG;
 202
 203                call->buffer = kmalloc(call->count * 3 * 4, GFP_KERNEL);
 204                if (!call->buffer)
 205                        return -ENOMEM;
 206                call->offset = 0;
 207                call->unmarshall++;
 208
 209        case 2:
 210                _debug("extract FID array");
 211                ret = afs_extract_data(call, skb, last, call->buffer,
 212                                       call->count * 3 * 4);
 213                switch (ret) {
 214                case 0:         break;
 215                case -EAGAIN:   return 0;
 216                default:        return ret;
 217                }
 218
 219                _debug("unmarshall FID array");
 220                call->request = kcalloc(call->count,
 221                                        sizeof(struct afs_callback),
 222                                        GFP_KERNEL);
 223                if (!call->request)
 224                        return -ENOMEM;
 225
 226                cb = call->request;
 227                bp = call->buffer;
 228                for (loop = call->count; loop > 0; loop--, cb++) {
 229                        cb->fid.vid     = ntohl(*bp++);
 230                        cb->fid.vnode   = ntohl(*bp++);
 231                        cb->fid.unique  = ntohl(*bp++);
 232                        cb->type        = AFSCM_CB_UNTYPED;
 233                }
 234
 235                call->offset = 0;
 236                call->unmarshall++;
 237
 238                /* extract the callback array and its count in two steps */
 239        case 3:
 240                _debug("extract CB count");
 241                ret = afs_extract_data(call, skb, last, &call->tmp, 4);
 242                switch (ret) {
 243                case 0:         break;
 244                case -EAGAIN:   return 0;
 245                default:        return ret;
 246                }
 247
 248                tmp = ntohl(call->tmp);
 249                _debug("CB count: %u", tmp);
 250                if (tmp != call->count && tmp != 0)
 251                        return -EBADMSG;
 252                call->offset = 0;
 253                call->unmarshall++;
 254                if (tmp == 0)
 255                        goto empty_cb_array;
 256
 257        case 4:
 258                _debug("extract CB array");
 259                ret = afs_extract_data(call, skb, last, call->request,
 260                                       call->count * 3 * 4);
 261                switch (ret) {
 262                case 0:         break;
 263                case -EAGAIN:   return 0;
 264                default:        return ret;
 265                }
 266
 267                _debug("unmarshall CB array");
 268                cb = call->request;
 269                bp = call->buffer;
 270                for (loop = call->count; loop > 0; loop--, cb++) {
 271                        cb->version     = ntohl(*bp++);
 272                        cb->expiry      = ntohl(*bp++);
 273                        cb->type        = ntohl(*bp++);
 274                }
 275
 276        empty_cb_array:
 277                call->offset = 0;
 278                call->unmarshall++;
 279
 280        case 5:
 281                _debug("trailer");
 282                if (skb->len != 0)
 283                        return -EBADMSG;
 284
 285                /* Record that the message was unmarshalled successfully so
 286                 * that the call destructor can know do the callback breaking
 287                 * work, even if the final ACK isn't received.
 288                 *
 289                 * If the step number changes, then afs_cm_destructor() must be
 290                 * updated also.
 291                 */
 292                call->unmarshall++;
 293        case 6:
 294                break;
 295        }
 296
 297        if (!last)
 298                return 0;
 299
 300        call->state = AFS_CALL_REPLYING;
 301
 302        /* we'll need the file server record as that tells us which set of
 303         * vnodes to operate upon */
 304        memcpy(&addr, &ip_hdr(skb)->saddr, 4);
 305        server = afs_find_server(&addr);
 306        if (!server)
 307                return -ENOTCONN;
 308        call->server = server;
 309
 310        INIT_WORK(&call->work, SRXAFSCB_CallBack);
 311        queue_work(afs_wq, &call->work);
 312        return 0;
 313}
 314
 315/*
 316 * allow the fileserver to request callback state (re-)initialisation
 317 */
 318static void SRXAFSCB_InitCallBackState(struct work_struct *work)
 319{
 320        struct afs_call *call = container_of(work, struct afs_call, work);
 321
 322        _enter("{%p}", call->server);
 323
 324        afs_init_callback_state(call->server);
 325        afs_send_empty_reply(call);
 326        _leave("");
 327}
 328
 329/*
 330 * deliver request data to a CB.InitCallBackState call
 331 */
 332static int afs_deliver_cb_init_call_back_state(struct afs_call *call,
 333                                               struct sk_buff *skb,
 334                                               bool last)
 335{
 336        struct afs_server *server;
 337        struct in_addr addr;
 338
 339        _enter(",{%u},%d", skb->len, last);
 340
 341        if (skb->len > 0)
 342                return -EBADMSG;
 343        if (!last)
 344                return 0;
 345
 346        /* no unmarshalling required */
 347        call->state = AFS_CALL_REPLYING;
 348
 349        /* we'll need the file server record as that tells us which set of
 350         * vnodes to operate upon */
 351        memcpy(&addr, &ip_hdr(skb)->saddr, 4);
 352        server = afs_find_server(&addr);
 353        if (!server)
 354                return -ENOTCONN;
 355        call->server = server;
 356
 357        INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
 358        queue_work(afs_wq, &call->work);
 359        return 0;
 360}
 361
 362/*
 363 * deliver request data to a CB.InitCallBackState3 call
 364 */
 365static int afs_deliver_cb_init_call_back_state3(struct afs_call *call,
 366                                                struct sk_buff *skb,
 367                                                bool last)
 368{
 369        struct afs_server *server;
 370        struct in_addr addr;
 371
 372        _enter(",{%u},%d", skb->len, last);
 373
 374        if (!last)
 375                return 0;
 376
 377        /* no unmarshalling required */
 378        call->state = AFS_CALL_REPLYING;
 379
 380        /* we'll need the file server record as that tells us which set of
 381         * vnodes to operate upon */
 382        memcpy(&addr, &ip_hdr(skb)->saddr, 4);
 383        server = afs_find_server(&addr);
 384        if (!server)
 385                return -ENOTCONN;
 386        call->server = server;
 387
 388        INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
 389        queue_work(afs_wq, &call->work);
 390        return 0;
 391}
 392
 393/*
 394 * allow the fileserver to see if the cache manager is still alive
 395 */
 396static void SRXAFSCB_Probe(struct work_struct *work)
 397{
 398        struct afs_call *call = container_of(work, struct afs_call, work);
 399
 400        _enter("");
 401        afs_send_empty_reply(call);
 402        _leave("");
 403}
 404
 405/*
 406 * deliver request data to a CB.Probe call
 407 */
 408static int afs_deliver_cb_probe(struct afs_call *call, struct sk_buff *skb,
 409                                bool last)
 410{
 411        _enter(",{%u},%d", skb->len, last);
 412
 413        if (skb->len > 0)
 414                return -EBADMSG;
 415        if (!last)
 416                return 0;
 417
 418        /* no unmarshalling required */
 419        call->state = AFS_CALL_REPLYING;
 420
 421        INIT_WORK(&call->work, SRXAFSCB_Probe);
 422        queue_work(afs_wq, &call->work);
 423        return 0;
 424}
 425
 426/*
 427 * allow the fileserver to quickly find out if the fileserver has been rebooted
 428 */
 429static void SRXAFSCB_ProbeUuid(struct work_struct *work)
 430{
 431        struct afs_call *call = container_of(work, struct afs_call, work);
 432        struct afs_uuid *r = call->request;
 433
 434        struct {
 435                __be32  match;
 436        } reply;
 437
 438        _enter("");
 439
 440
 441        if (memcmp(r, &afs_uuid, sizeof(afs_uuid)) == 0)
 442                reply.match = htonl(0);
 443        else
 444                reply.match = htonl(1);
 445
 446        afs_send_simple_reply(call, &reply, sizeof(reply));
 447        _leave("");
 448}
 449
 450/*
 451 * deliver request data to a CB.ProbeUuid call
 452 */
 453static int afs_deliver_cb_probe_uuid(struct afs_call *call, struct sk_buff *skb,
 454                                     bool last)
 455{
 456        struct afs_uuid *r;
 457        unsigned loop;
 458        __be32 *b;
 459        int ret;
 460
 461        _enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
 462
 463        if (skb->len > 0)
 464                return -EBADMSG;
 465        if (!last)
 466                return 0;
 467
 468        switch (call->unmarshall) {
 469        case 0:
 470                call->offset = 0;
 471                call->buffer = kmalloc(11 * sizeof(__be32), GFP_KERNEL);
 472                if (!call->buffer)
 473                        return -ENOMEM;
 474                call->unmarshall++;
 475
 476        case 1:
 477                _debug("extract UUID");
 478                ret = afs_extract_data(call, skb, last, call->buffer,
 479                                       11 * sizeof(__be32));
 480                switch (ret) {
 481                case 0:         break;
 482                case -EAGAIN:   return 0;
 483                default:        return ret;
 484                }
 485
 486                _debug("unmarshall UUID");
 487                call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
 488                if (!call->request)
 489                        return -ENOMEM;
 490
 491                b = call->buffer;
 492                r = call->request;
 493                r->time_low                     = ntohl(b[0]);
 494                r->time_mid                     = ntohl(b[1]);
 495                r->time_hi_and_version          = ntohl(b[2]);
 496                r->clock_seq_hi_and_reserved    = ntohl(b[3]);
 497                r->clock_seq_low                = ntohl(b[4]);
 498
 499                for (loop = 0; loop < 6; loop++)
 500                        r->node[loop] = ntohl(b[loop + 5]);
 501
 502                call->offset = 0;
 503                call->unmarshall++;
 504
 505        case 2:
 506                _debug("trailer");
 507                if (skb->len != 0)
 508                        return -EBADMSG;
 509                break;
 510        }
 511
 512        if (!last)
 513                return 0;
 514
 515        call->state = AFS_CALL_REPLYING;
 516
 517        INIT_WORK(&call->work, SRXAFSCB_ProbeUuid);
 518        queue_work(afs_wq, &call->work);
 519        return 0;
 520}
 521
 522/*
 523 * allow the fileserver to ask about the cache manager's capabilities
 524 */
 525static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
 526{
 527        struct afs_interface *ifs;
 528        struct afs_call *call = container_of(work, struct afs_call, work);
 529        int loop, nifs;
 530
 531        struct {
 532                struct /* InterfaceAddr */ {
 533                        __be32 nifs;
 534                        __be32 uuid[11];
 535                        __be32 ifaddr[32];
 536                        __be32 netmask[32];
 537                        __be32 mtu[32];
 538                } ia;
 539                struct /* Capabilities */ {
 540                        __be32 capcount;
 541                        __be32 caps[1];
 542                } cap;
 543        } reply;
 544
 545        _enter("");
 546
 547        nifs = 0;
 548        ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
 549        if (ifs) {
 550                nifs = afs_get_ipv4_interfaces(ifs, 32, false);
 551                if (nifs < 0) {
 552                        kfree(ifs);
 553                        ifs = NULL;
 554                        nifs = 0;
 555                }
 556        }
 557
 558        memset(&reply, 0, sizeof(reply));
 559        reply.ia.nifs = htonl(nifs);
 560
 561        reply.ia.uuid[0] = htonl(afs_uuid.time_low);
 562        reply.ia.uuid[1] = htonl(afs_uuid.time_mid);
 563        reply.ia.uuid[2] = htonl(afs_uuid.time_hi_and_version);
 564        reply.ia.uuid[3] = htonl((s8) afs_uuid.clock_seq_hi_and_reserved);
 565        reply.ia.uuid[4] = htonl((s8) afs_uuid.clock_seq_low);
 566        for (loop = 0; loop < 6; loop++)
 567                reply.ia.uuid[loop + 5] = htonl((s8) afs_uuid.node[loop]);
 568
 569        if (ifs) {
 570                for (loop = 0; loop < nifs; loop++) {
 571                        reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
 572                        reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
 573                        reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
 574                }
 575                kfree(ifs);
 576        }
 577
 578        reply.cap.capcount = htonl(1);
 579        reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
 580        afs_send_simple_reply(call, &reply, sizeof(reply));
 581
 582        _leave("");
 583}
 584
 585/*
 586 * deliver request data to a CB.TellMeAboutYourself call
 587 */
 588static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call,
 589                                                 struct sk_buff *skb, bool last)
 590{
 591        _enter(",{%u},%d", skb->len, last);
 592
 593        if (skb->len > 0)
 594                return -EBADMSG;
 595        if (!last)
 596                return 0;
 597
 598        /* no unmarshalling required */
 599        call->state = AFS_CALL_REPLYING;
 600
 601        INIT_WORK(&call->work, SRXAFSCB_TellMeAboutYourself);
 602        queue_work(afs_wq, &call->work);
 603        return 0;
 604}
 605