fs/lockd/svcproc.c

   1 /*
   2  * linux/fs/lockd/svcproc.c
   3  *
   4  * Lockd server procedures. We don't implement the NLM_*_RES
   5  * procedures because we don't use the async procedures.
   6  *
   7  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/time.h>
  12 #include <linux/slab.h>
  13 #include <linux/in.h>
  14 #include <linux/sunrpc/svc.h>
  15 #include <linux/sunrpc/clnt.h>
  16 #include <linux/nfsd/nfsd.h>
  17 #include <linux/lockd/lockd.h>
  18 #include <linux/lockd/share.h>
  19 #include <linux/lockd/sm_inter.h>
  20
  21
  22 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  23
  24 #ifdef CONFIG_LOCKD_V4
  25 static __be32
  26 cast_to_nlm(__be32 status, u32 vers)
  27 {
  28         /* Note: status is assumed to be in network byte order !!! */
  29         if (vers != 4){
  30                 switch (status) {
  31                 case nlm_granted:
  32                 case nlm_lck_denied:
  33                 case nlm_lck_denied_nolocks:
  34                 case nlm_lck_blocked:
  35                 case nlm_lck_denied_grace_period:
  36                 case nlm_drop_reply:
  37                         break;
  38                 case nlm4_deadlock:
  39                         status = nlm_lck_denied;
  40                         break;
  41                 default:
  42                         status = nlm_lck_denied_nolocks;
  43                 }
  44         }
  45
  46         return (status);
  47 }
  48 #define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
  49 #else
  50 #define cast_status(status) (status)
  51 #endif
  52
  53 /*
  54  * Obtain client and file from arguments
  55  */
  56 static __be32
  57 nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  58                         struct nlm_host **hostp, struct nlm_file **filp)
  59 {
  60         struct nlm_host         *host = NULL;
  61         struct nlm_file         *file = NULL;
  62         struct nlm_lock         *lock = &argp->lock;
  63         __be32                  error = 0;
  64
  65         /* nfsd callbacks must have been installed for this procedure */
  66         if (!nlmsvc_ops)
  67                 return nlm_lck_denied_nolocks;
  68
  69         /* Obtain host handle */
  70         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  71          || (argp->monitor && nsm_monitor(host) < 0))
  72                 goto no_locks;
  73         *hostp = host;
  74
  75         /* Obtain file pointer. Not used by FREE_ALL call. */
  76         if (filp != NULL) {
  77                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  78                         goto no_locks;
  79                 *filp = file;
  80
  81                 /* Set up the missing parts of the file_lock structure */
  82                 lock->fl.fl_file  = file->f_file;
  83                 lock->fl.fl_owner = (fl_owner_t) host;
  84                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  85         }
  86
  87         return 0;
  88
  89 no_locks:
  90         nlm_release_host(host);
  91         if (error)
  92                 return error;
  93         return nlm_lck_denied_nolocks;
  94 }
  95
  96 /*
  97  * NULL: Test for presence of service
  98  */
  99 static __be32
 100 nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
 101 {
 102         dprintk("lockd: NULL          called\n");
 103         return rpc_success;
 104 }
 105
 106 /*
 107  * TEST: Check for conflicting lock
 108  */
 109 static __be32
 110 nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
 111                                          struct nlm_res  *resp)
 112 {
 113         struct nlm_host *host;
 114         struct nlm_file *file;
 115         __be32 rc = rpc_success;
 116
 117         dprintk("lockd: TEST          called\n");
 118         resp->cookie = argp->cookie;
 119
 120         /* Don't accept test requests during grace period */
 121         if (nlmsvc_grace_period) {
 122                 resp->status = nlm_lck_denied_grace_period;
 123                 return rc;
 124         }
 125
 126         /* Obtain client and file */
 127         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 128                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 129
 130         /* Now check for conflicting locks */
 131         resp->status = cast_status(nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie));
 132         if (resp->status == nlm_drop_reply)
 133                 rc = rpc_drop_reply;
 134         else
 135                 dprintk("lockd: TEST          status %d vers %d\n",
 136                         ntohl(resp->status), rqstp->rq_vers);
 137
 138         nlm_release_host(host);
 139         nlm_release_file(file);
 140         return rc;
 141 }
 142
 143 static __be32
 144 nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 145                                          struct nlm_res  *resp)
 146 {
 147         struct nlm_host *host;
 148         struct nlm_file *file;
 149         __be32 rc = rpc_success;
 150
 151         dprintk("lockd: LOCK          called\n");
 152
 153         resp->cookie = argp->cookie;
 154
 155         /* Don't accept new lock requests during grace period */
 156         if (nlmsvc_grace_period && !argp->reclaim) {
 157                 resp->status = nlm_lck_denied_grace_period;
 158                 return rc;
 159         }
 160
 161         /* Obtain client and file */
 162         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 163                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 164
 165 #if 0
 166         /* If supplied state doesn't match current state, we assume it's
 167          * an old request that time-warped somehow. Any error return would
 168          * do in this case because it's irrelevant anyway.
 169          *
 170          * NB: We don't retrieve the remote host's state yet.
 171          */
 172         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 173                 resp->status = nlm_lck_denied_nolocks;
 174         } else
 175 #endif
 176
 177         /* Now try to lock the file */
 178         resp->status = cast_status(nlmsvc_lock(rqstp, file, host, &argp->lock,
 179                                                argp->block, &argp->cookie));
 180         if (resp->status == nlm_drop_reply)
 181                 rc = rpc_drop_reply;
 182         else
 183                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 184
 185         nlm_release_host(host);
 186         nlm_release_file(file);
 187         return rc;
 188 }
 189
 190 static __be32
 191 nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 192                                            struct nlm_res  *resp)
 193 {
 194         struct nlm_host *host;
 195         struct nlm_file *file;
 196
 197         dprintk("lockd: CANCEL        called\n");
 198
 199         resp->cookie = argp->cookie;
 200
 201         /* Don't accept requests during grace period */
 202         if (nlmsvc_grace_period) {
 203                 resp->status = nlm_lck_denied_grace_period;
 204                 return rpc_success;
 205         }
 206
 207         /* Obtain client and file */
 208         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 209                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 210
 211         /* Try to cancel request. */
 212         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 213
 214         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 215         nlm_release_host(host);
 216         nlm_release_file(file);
 217         return rpc_success;
 218 }
 219
 220 /*
 221  * UNLOCK: release a lock
 222  */
 223 static __be32
 224 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 225                                            struct nlm_res  *resp)
 226 {
 227         struct nlm_host *host;
 228         struct nlm_file *file;
 229
 230         dprintk("lockd: UNLOCK        called\n");
 231
 232         resp->cookie = argp->cookie;
 233
 234         /* Don't accept new lock requests during grace period */
 235         if (nlmsvc_grace_period) {
 236                 resp->status = nlm_lck_denied_grace_period;
 237                 return rpc_success;
 238         }
 239
 240         /* Obtain client and file */
 241         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 242                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 243
 244         /* Now try to remove the lock */
 245         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 246
 247         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 248         nlm_release_host(host);
 249         nlm_release_file(file);
 250         return rpc_success;
 251 }
 252
 253 /*
 254  * GRANTED: A server calls us to tell that a process' lock request
 255  * was granted
 256  */
 257 static __be32
 258 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 259                                             struct nlm_res  *resp)
 260 {
 261         resp->cookie = argp->cookie;
 262
 263         dprintk("lockd: GRANTED       called\n");
 264         resp->status = nlmclnt_grant(svc_addr_in(rqstp), &argp->lock);
 265         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 266         return rpc_success;
 267 }
 268
 269 /*
 270  * This is the generic lockd callback for async RPC calls
 271  */
 272 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 273 {
 274         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 275                         -task->tk_status);
 276 }
 277
 278 static void nlmsvc_callback_release(void *data)
 279 {
 280         lock_kernel();
 281         nlm_release_call(data);
 282         unlock_kernel();
 283 }
 284
 285 static const struct rpc_call_ops nlmsvc_callback_ops = {
 286         .rpc_call_done = nlmsvc_callback_exit,
 287         .rpc_release = nlmsvc_callback_release,
 288 };
 289
 290 /*
 291  * `Async' versions of the above service routines. They aren't really,
 292  * because we send the callback before the reply proper. I hope this
 293  * doesn't break any clients.
 294  */
 295 static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 296                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 297 {
 298         struct nlm_host *host;
 299         struct nlm_rqst *call;
 300         __be32 stat;
 301
 302         host = nlmsvc_lookup_host(rqstp,
 303                                   argp->lock.caller,
 304                                   argp->lock.len);
 305         if (host == NULL)
 306                 return rpc_system_err;
 307
 308         call = nlm_alloc_call(host);
 309         if (call == NULL)
 310                 return rpc_system_err;
 311
 312         stat = func(rqstp, argp, &call->a_res);
 313         if (stat != 0) {
 314                 nlm_release_call(call);
 315                 return stat;
 316         }
 317
 318         call->a_flags = RPC_TASK_ASYNC;
 319         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 320                 return rpc_system_err;
 321         return rpc_success;
 322 }
 323
 324 static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 325                                              void            *resp)
 326 {
 327         dprintk("lockd: TEST_MSG      called\n");
 328         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 329 }
 330
 331 static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 332                                              void            *resp)
 333 {
 334         dprintk("lockd: LOCK_MSG      called\n");
 335         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 336 }
 337
 338 static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 339                                                void            *resp)
 340 {
 341         dprintk("lockd: CANCEL_MSG    called\n");
 342         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 343 }
 344
 345 static __be32
 346 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 347                                                void            *resp)
 348 {
 349         dprintk("lockd: UNLOCK_MSG    called\n");
 350         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 351 }
 352
 353 static __be32
 354 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 355                                                 void            *resp)
 356 {
 357         dprintk("lockd: GRANTED_MSG   called\n");
 358         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 359 }
 360
 361 /*
 362  * SHARE: create a DOS share or alter existing share.
 363  */
 364 static __be32
 365 nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 366                                           struct nlm_res  *resp)
 367 {
 368         struct nlm_host *host;
 369         struct nlm_file *file;
 370
 371         dprintk("lockd: SHARE         called\n");
 372
 373         resp->cookie = argp->cookie;
 374
 375         /* Don't accept new lock requests during grace period */
 376         if (nlmsvc_grace_period && !argp->reclaim) {
 377                 resp->status = nlm_lck_denied_grace_period;
 378                 return rpc_success;
 379         }
 380
 381         /* Obtain client and file */
 382         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 383                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 384
 385         /* Now try to create the share */
 386         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 387
 388         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 389         nlm_release_host(host);
 390         nlm_release_file(file);
 391         return rpc_success;
 392 }
 393
 394 /*
 395  * UNSHARE: Release a DOS share.
 396  */
 397 static __be32
 398 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 399                                             struct nlm_res  *resp)
 400 {
 401         struct nlm_host *host;
 402         struct nlm_file *file;
 403
 404         dprintk("lockd: UNSHARE       called\n");
 405
 406         resp->cookie = argp->cookie;
 407
 408         /* Don't accept requests during grace period */
 409         if (nlmsvc_grace_period) {
 410                 resp->status = nlm_lck_denied_grace_period;
 411                 return rpc_success;
 412         }
 413
 414         /* Obtain client and file */
 415         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 416                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 417
 418         /* Now try to unshare the file */
 419         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 420
 421         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 422         nlm_release_host(host);
 423         nlm_release_file(file);
 424         return rpc_success;
 425 }
 426
 427 /*
 428  * NM_LOCK: Create an unmonitored lock
 429  */
 430 static __be32
 431 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 432                                             struct nlm_res  *resp)
 433 {
 434         dprintk("lockd: NM_LOCK       called\n");
 435
 436         argp->monitor = 0;              /* just clean the monitor flag */
 437         return nlmsvc_proc_lock(rqstp, argp, resp);
 438 }
 439
 440 /*
 441  * FREE_ALL: Release all locks and shares held by client
 442  */
 443 static __be32
 444 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 445                                              void            *resp)
 446 {
 447         struct nlm_host *host;
 448
 449         /* Obtain client */
 450         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 451                 return rpc_success;
 452
 453         nlmsvc_free_host_resources(host);
 454         nlm_release_host(host);
 455         return rpc_success;
 456 }
 457
 458 /*
 459  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 460  */
 461 static __be32
 462 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 463                                               void              *resp)
 464 {
 465         struct sockaddr_in      saddr;
 466
 467         memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
 468
 469         dprintk("lockd: SM_NOTIFY     called\n");
 470         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 471          || ntohs(saddr.sin_port) >= 1024) {
 472                 char buf[RPC_MAX_ADDRBUFLEN];
 473                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 474                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 475                 return rpc_system_err;
 476         }
 477
 478         /* Obtain the host pointer for this NFS server and try to
 479          * reclaim all locks we hold on this server.
 480          */
 481         memset(&saddr, 0, sizeof(saddr));
 482         saddr.sin_addr.s_addr = argp->addr;
 483         nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
 484
 485         return rpc_success;
 486 }
 487
 488 /*
 489  * client sent a GRANTED_RES, let's remove the associated block
 490  */
 491 static __be32
 492 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 493                                                 void            *resp)
 494 {
 495         if (!nlmsvc_ops)
 496                 return rpc_success;
 497
 498         dprintk("lockd: GRANTED_RES   called\n");
 499
 500         nlmsvc_grant_reply(&argp->cookie, argp->status);
 501         return rpc_success;
 502 }
 503
 504 /*
 505  * NLM Server procedures.
 506  */
 507
 508 #define nlmsvc_encode_norep     nlmsvc_encode_void
 509 #define nlmsvc_decode_norep     nlmsvc_decode_void
 510 #define nlmsvc_decode_testres   nlmsvc_decode_void
 511 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 512 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 513 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 514 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 515
 516 #define nlmsvc_proc_none        nlmsvc_proc_null
 517 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 518 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 519 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 520 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 521
 522 struct nlm_void                 { int dummy; };
 523
 524 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 525  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 526    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 527    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 528    .pc_release  = NULL,                                 \
 529    .pc_argsize  = sizeof(struct nlm_##argt),            \
 530    .pc_ressize  = sizeof(struct nlm_##rest),            \
 531    .pc_xdrressize = respsize,                           \
 532  }
 533
 534 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 535 #define St      1                               /* status */
 536 #define No      (1+1024/4)                      /* Net Obj */
 537 #define Rg      2                               /* range - offset + size */
 538
 539 struct svc_procedure            nlmsvc_procedures[] = {
 540   PROC(null,            void,           void,           void,   void, 1),
 541   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 542   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 543   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 544   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 545   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 546   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 547   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 548   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 549   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 550   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 551   PROC(test_res,        testres,        norep,          res,    void, 1),
 552   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 553   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 554   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 555   PROC(granted_res,     res,            norep,          res,    void, 1),
 556   /* statd callback */
 557   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 558   PROC(none,            void,           void,           void,   void, 1),
 559   PROC(none,            void,           void,           void,   void, 1),
 560   PROC(none,            void,           void,           void,   void, 1),
 561   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 562   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 563   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 564   PROC(free_all,        notify,         void,           args,   void, 0),
 565
 566 };