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