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 u32
  26 cast_to_nlm(u32 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                         break;
  37                 case nlm4_deadlock:
  38                         status = nlm_lck_denied;
  39                         break;
  40                 default:
  41                         status = nlm_lck_denied_nolocks;
  42                 }
  43         }
  44
  45         return (status);
  46 }
  47 #define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
  48 #else
  49 #define cast_status(status) (status)
  50 #endif
  51
  52 /*
  53  * Obtain client and file from arguments
  54  */
  55 static u32
  56 nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  57                         struct nlm_host **hostp, struct nlm_file **filp)
  58 {
  59         struct nlm_host         *host = NULL;
  60         struct nlm_file         *file = NULL;
  61         struct nlm_lock         *lock = &argp->lock;
  62         u32                     error;
  63
  64         /* nfsd callbacks must have been installed for this procedure */
  65         if (!nlmsvc_ops)
  66                 return nlm_lck_denied_nolocks;
  67
  68         /* Obtain host handle */
  69         if (!(host = nlmsvc_lookup_host(rqstp))
  70          || (argp->monitor && !host->h_monitored && nsm_monitor(host) < 0))
  71                 goto no_locks;
  72         *hostp = host;
  73
  74         /* Obtain file pointer. Not used by FREE_ALL call. */
  75         if (filp != NULL) {
  76                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  77                         goto no_locks;
  78                 *filp = file;
  79
  80                 /* Set up the missing parts of the file_lock structure */
  81                 lock->fl.fl_file  = file->f_file;
  82                 lock->fl.fl_owner = (fl_owner_t) host;
  83                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  84         }
  85
  86         return 0;
  87
  88 no_locks:
  89         if (host)
  90                 nlm_release_host(host);
  91         return nlm_lck_denied_nolocks;
  92 }
  93
  94 /*
  95  * NULL: Test for presence of service
  96  */
  97 static int
  98 nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  99 {
 100         dprintk("lockd: NULL          called\n");
 101         return rpc_success;
 102 }
 103
 104 /*
 105  * TEST: Check for conflicting lock
 106  */
 107 static int
 108 nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
 109                                          struct nlm_res  *resp)
 110 {
 111         struct nlm_host *host;
 112         struct nlm_file *file;
 113
 114         dprintk("lockd: TEST          called\n");
 115         resp->cookie = argp->cookie;
 116
 117         /* Don't accept test requests during grace period */
 118         if (nlmsvc_grace_period) {
 119                 resp->status = nlm_lck_denied_grace_period;
 120                 return rpc_success;
 121         }
 122
 123         /* Obtain client and file */
 124         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 125                 return rpc_success;
 126
 127         /* Now check for conflicting locks */
 128         resp->status = cast_status(nlmsvc_testlock(file, &argp->lock, &resp->lock));
 129
 130         dprintk("lockd: TEST          status %d vers %d\n",
 131                 ntohl(resp->status), rqstp->rq_vers);
 132         nlm_release_host(host);
 133         nlm_release_file(file);
 134         return rpc_success;
 135 }
 136
 137 static int
 138 nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 139                                          struct nlm_res  *resp)
 140 {
 141         struct nlm_host *host;
 142         struct nlm_file *file;
 143
 144         dprintk("lockd: LOCK          called\n");
 145
 146         resp->cookie = argp->cookie;
 147
 148         /* Don't accept new lock requests during grace period */
 149         if (nlmsvc_grace_period && !argp->reclaim) {
 150                 resp->status = nlm_lck_denied_grace_period;
 151                 return rpc_success;
 152         }
 153
 154         /* Obtain client and file */
 155         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 156                 return rpc_success;
 157
 158 #if 0
 159         /* If supplied state doesn't match current state, we assume it's
 160          * an old request that time-warped somehow. Any error return would
 161          * do in this case because it's irrelevant anyway.
 162          *
 163          * NB: We don't retrieve the remote host's state yet.
 164          */
 165         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 166                 resp->status = nlm_lck_denied_nolocks;
 167         } else
 168 #endif
 169
 170         /* Now try to lock the file */
 171         resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
 172                                                argp->block, &argp->cookie));
 173
 174         dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
 175         nlm_release_host(host);
 176         nlm_release_file(file);
 177         return rpc_success;
 178 }
 179
 180 static int
 181 nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 182                                            struct nlm_res  *resp)
 183 {
 184         struct nlm_host *host;
 185         struct nlm_file *file;
 186
 187         dprintk("lockd: CANCEL        called\n");
 188
 189         resp->cookie = argp->cookie;
 190
 191         /* Don't accept requests during grace period */
 192         if (nlmsvc_grace_period) {
 193                 resp->status = nlm_lck_denied_grace_period;
 194                 return rpc_success;
 195         }
 196
 197         /* Obtain client and file */
 198         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 199                 return rpc_success;
 200
 201         /* Try to cancel request. */
 202         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 203
 204         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 205         nlm_release_host(host);
 206         nlm_release_file(file);
 207         return rpc_success;
 208 }
 209
 210 /*
 211  * UNLOCK: release a lock
 212  */
 213 static int
 214 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 215                                            struct nlm_res  *resp)
 216 {
 217         struct nlm_host *host;
 218         struct nlm_file *file;
 219
 220         dprintk("lockd: UNLOCK        called\n");
 221
 222         resp->cookie = argp->cookie;
 223
 224         /* Don't accept new lock requests during grace period */
 225         if (nlmsvc_grace_period) {
 226                 resp->status = nlm_lck_denied_grace_period;
 227                 return rpc_success;
 228         }
 229
 230         /* Obtain client and file */
 231         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 232                 return rpc_success;
 233
 234         /* Now try to remove the lock */
 235         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 236
 237         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 238         nlm_release_host(host);
 239         nlm_release_file(file);
 240         return rpc_success;
 241 }
 242
 243 /*
 244  * GRANTED: A server calls us to tell that a process' lock request
 245  * was granted
 246  */
 247 static int
 248 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 249                                             struct nlm_res  *resp)
 250 {
 251         resp->cookie = argp->cookie;
 252
 253         dprintk("lockd: GRANTED       called\n");
 254         resp->status = nlmclnt_grant(&rqstp->rq_addr, &argp->lock);
 255         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 256         return rpc_success;
 257 }
 258
 259 /*
 260  * This is the generic lockd callback for async RPC calls
 261  */
 262 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 263 {
 264         dprintk("lockd: %4d callback returned %d\n", task->tk_pid,
 265                         -task->tk_status);
 266 }
 267
 268 static void nlmsvc_callback_release(void *data)
 269 {
 270         nlm_release_call(data);
 271 }
 272
 273 static const struct rpc_call_ops nlmsvc_callback_ops = {
 274         .rpc_call_done = nlmsvc_callback_exit,
 275         .rpc_release = nlmsvc_callback_release,
 276 };
 277
 278 /*
 279  * `Async' versions of the above service routines. They aren't really,
 280  * because we send the callback before the reply proper. I hope this
 281  * doesn't break any clients.
 282  */
 283 static int nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 284                 int (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 285 {
 286         struct nlm_host *host;
 287         struct nlm_rqst *call;
 288         int stat;
 289
 290         host = nlmsvc_lookup_host(rqstp);
 291         if (host == NULL)
 292                 return rpc_system_err;
 293
 294         call = nlm_alloc_call(host);
 295         if (call == NULL)
 296                 return rpc_system_err;
 297
 298         stat = func(rqstp, argp, &call->a_res);
 299         if (stat != 0) {
 300                 nlm_release_call(call);
 301                 return stat;
 302         }
 303
 304         call->a_flags = RPC_TASK_ASYNC;
 305         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 306                 return rpc_system_err;
 307         return rpc_success;
 308 }
 309
 310 static int nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 311                                              void            *resp)
 312 {
 313         dprintk("lockd: TEST_MSG      called\n");
 314         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 315 }
 316
 317 static int nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 318                                              void            *resp)
 319 {
 320         dprintk("lockd: LOCK_MSG      called\n");
 321         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 322 }
 323
 324 static int nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 325                                                void            *resp)
 326 {
 327         dprintk("lockd: CANCEL_MSG    called\n");
 328         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 329 }
 330
 331 static int
 332 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 333                                                void            *resp)
 334 {
 335         dprintk("lockd: UNLOCK_MSG    called\n");
 336         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 337 }
 338
 339 static int
 340 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 341                                                 void            *resp)
 342 {
 343         dprintk("lockd: GRANTED_MSG   called\n");
 344         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 345 }
 346
 347 /*
 348  * SHARE: create a DOS share or alter existing share.
 349  */
 350 static int
 351 nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 352                                           struct nlm_res  *resp)
 353 {
 354         struct nlm_host *host;
 355         struct nlm_file *file;
 356
 357         dprintk("lockd: SHARE         called\n");
 358
 359         resp->cookie = argp->cookie;
 360
 361         /* Don't accept new lock requests during grace period */
 362         if (nlmsvc_grace_period && !argp->reclaim) {
 363                 resp->status = nlm_lck_denied_grace_period;
 364                 return rpc_success;
 365         }
 366
 367         /* Obtain client and file */
 368         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 369                 return rpc_success;
 370
 371         /* Now try to create the share */
 372         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 373
 374         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 375         nlm_release_host(host);
 376         nlm_release_file(file);
 377         return rpc_success;
 378 }
 379
 380 /*
 381  * UNSHARE: Release a DOS share.
 382  */
 383 static int
 384 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 385                                             struct nlm_res  *resp)
 386 {
 387         struct nlm_host *host;
 388         struct nlm_file *file;
 389
 390         dprintk("lockd: UNSHARE       called\n");
 391
 392         resp->cookie = argp->cookie;
 393
 394         /* Don't accept requests during grace period */
 395         if (nlmsvc_grace_period) {
 396                 resp->status = nlm_lck_denied_grace_period;
 397                 return rpc_success;
 398         }
 399
 400         /* Obtain client and file */
 401         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 402                 return rpc_success;
 403
 404         /* Now try to unshare the file */
 405         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 406
 407         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 408         nlm_release_host(host);
 409         nlm_release_file(file);
 410         return rpc_success;
 411 }
 412
 413 /*
 414  * NM_LOCK: Create an unmonitored lock
 415  */
 416 static int
 417 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 418                                             struct nlm_res  *resp)
 419 {
 420         dprintk("lockd: NM_LOCK       called\n");
 421
 422         argp->monitor = 0;              /* just clean the monitor flag */
 423         return nlmsvc_proc_lock(rqstp, argp, resp);
 424 }
 425
 426 /*
 427  * FREE_ALL: Release all locks and shares held by client
 428  */
 429 static int
 430 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 431                                              void            *resp)
 432 {
 433         struct nlm_host *host;
 434
 435         /* Obtain client */
 436         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 437                 return rpc_success;
 438
 439         nlmsvc_free_host_resources(host);
 440         nlm_release_host(host);
 441         return rpc_success;
 442 }
 443
 444 /*
 445  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 446  */
 447 static int
 448 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 449                                               void              *resp)
 450 {
 451         struct sockaddr_in      saddr = rqstp->rq_addr;
 452         int                     vers = argp->vers;
 453         int                     prot = argp->proto >> 1;
 454         struct nlm_host         *host;
 455
 456         dprintk("lockd: SM_NOTIFY     called\n");
 457         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 458          || ntohs(saddr.sin_port) >= 1024) {
 459                 printk(KERN_WARNING
 460                         "lockd: rejected NSM callback from %08x:%d\n",
 461                         ntohl(rqstp->rq_addr.sin_addr.s_addr),
 462                         ntohs(rqstp->rq_addr.sin_port));
 463                 return rpc_system_err;
 464         }
 465
 466         /* Obtain the host pointer for this NFS server and try to
 467          * reclaim all locks we hold on this server.
 468          */
 469         saddr.sin_addr.s_addr = argp->addr;
 470         if ((argp->proto & 1)==0) {
 471                 if ((host = nlmclnt_lookup_host(&saddr, prot, vers)) != NULL) {
 472                         nlmclnt_recovery(host, argp->state);
 473                         nlm_release_host(host);
 474                 }
 475         } else {
 476                 /* If we run on an NFS server, delete all locks held by the client */
 477                 if ((host = nlm_lookup_host(1, &saddr, prot, vers)) != NULL) {
 478                         nlmsvc_free_host_resources(host);
 479                         nlm_release_host(host);
 480                 }
 481         }
 482
 483         return rpc_success;
 484 }
 485
 486 /*
 487  * client sent a GRANTED_RES, let's remove the associated block
 488  */
 489 static int
 490 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 491                                                 void            *resp)
 492 {
 493         if (!nlmsvc_ops)
 494                 return rpc_success;
 495
 496         dprintk("lockd: GRANTED_RES   called\n");
 497
 498         nlmsvc_grant_reply(rqstp, &argp->cookie, argp->status);
 499         return rpc_success;
 500 }
 501
 502 /*
 503  * NLM Server procedures.
 504  */
 505
 506 #define nlmsvc_encode_norep     nlmsvc_encode_void
 507 #define nlmsvc_decode_norep     nlmsvc_decode_void
 508 #define nlmsvc_decode_testres   nlmsvc_decode_void
 509 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 510 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 511 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 512 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 513
 514 #define nlmsvc_proc_none        nlmsvc_proc_null
 515 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 516 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 517 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 518 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 519
 520 struct nlm_void                 { int dummy; };
 521
 522 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 523  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 524    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 525    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 526    .pc_release  = NULL,                                 \
 527    .pc_argsize  = sizeof(struct nlm_##argt),            \
 528    .pc_ressize  = sizeof(struct nlm_##rest),            \
 529    .pc_xdrressize = respsize,                           \
 530  }
 531
 532 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 533 #define St      1                               /* status */
 534 #define No      (1+1024/4)                      /* Net Obj */
 535 #define Rg      2                               /* range - offset + size */
 536
 537 struct svc_procedure            nlmsvc_procedures[] = {
 538   PROC(null,            void,           void,           void,   void, 1),
 539   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 540   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 541   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 542   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 543   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 544   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 545   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 546   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 547   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 548   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 549   PROC(test_res,        testres,        norep,          res,    void, 1),
 550   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 551   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 552   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 553   PROC(granted_res,     res,            norep,          res,    void, 1),
 554   /* statd callback */
 555   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 556   PROC(none,            void,           void,           void,   void, 1),
 557   PROC(none,            void,           void,           void,   void, 1),
 558   PROC(none,            void,           void,           void,   void, 1),
 559   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 560   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 561   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 562   PROC(free_all,        notify,         void,           args,   void, 0),
 563
 564 };