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                         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 __be32
  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         __be32                  error = 0;
  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, lock->caller, lock->len))
  70          || (argp->monitor && 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         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
 116         dprintk("lockd: TEST          called\n");
 117         resp->cookie = argp->cookie;
 118
 119         /* Don't accept test requests during grace period */
 120         if (nlmsvc_grace_period) {
 121                 resp->status = nlm_lck_denied_grace_period;
 122                 return rpc_success;
 123         }
 124
 125         /* Obtain client and file */
 126         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 127                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 128
 129         /* Now check for conflicting locks */
 130         resp->status = cast_status(nlmsvc_testlock(file, &argp->lock, &resp->lock));
 131
 132         dprintk("lockd: TEST          status %d vers %d\n",
 133                 ntohl(resp->status), rqstp->rq_vers);
 134         nlm_release_host(host);
 135         nlm_release_file(file);
 136         return rpc_success;
 137 }
 138
 139 static __be32
 140 nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 141                                          struct nlm_res  *resp)
 142 {
 143         struct nlm_host *host;
 144         struct nlm_file *file;
 145
 146         dprintk("lockd: LOCK          called\n");
 147
 148         resp->cookie = argp->cookie;
 149
 150         /* Don't accept new lock requests during grace period */
 151         if (nlmsvc_grace_period && !argp->reclaim) {
 152                 resp->status = nlm_lck_denied_grace_period;
 153                 return rpc_success;
 154         }
 155
 156         /* Obtain client and file */
 157         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 158                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 159
 160 #if 0
 161         /* If supplied state doesn't match current state, we assume it's
 162          * an old request that time-warped somehow. Any error return would
 163          * do in this case because it's irrelevant anyway.
 164          *
 165          * NB: We don't retrieve the remote host's state yet.
 166          */
 167         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 168                 resp->status = nlm_lck_denied_nolocks;
 169         } else
 170 #endif
 171
 172         /* Now try to lock the file */
 173         resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
 174                                                argp->block, &argp->cookie));
 175
 176         dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
 177         nlm_release_host(host);
 178         nlm_release_file(file);
 179         return rpc_success;
 180 }
 181
 182 static __be32
 183 nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 184                                            struct nlm_res  *resp)
 185 {
 186         struct nlm_host *host;
 187         struct nlm_file *file;
 188
 189         dprintk("lockd: CANCEL        called\n");
 190
 191         resp->cookie = argp->cookie;
 192
 193         /* Don't accept requests during grace period */
 194         if (nlmsvc_grace_period) {
 195                 resp->status = nlm_lck_denied_grace_period;
 196                 return rpc_success;
 197         }
 198
 199         /* Obtain client and file */
 200         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 201                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 202
 203         /* Try to cancel request. */
 204         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 205
 206         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 207         nlm_release_host(host);
 208         nlm_release_file(file);
 209         return rpc_success;
 210 }
 211
 212 /*
 213  * UNLOCK: release a lock
 214  */
 215 static __be32
 216 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 217                                            struct nlm_res  *resp)
 218 {
 219         struct nlm_host *host;
 220         struct nlm_file *file;
 221
 222         dprintk("lockd: UNLOCK        called\n");
 223
 224         resp->cookie = argp->cookie;
 225
 226         /* Don't accept new lock requests during grace period */
 227         if (nlmsvc_grace_period) {
 228                 resp->status = nlm_lck_denied_grace_period;
 229                 return rpc_success;
 230         }
 231
 232         /* Obtain client and file */
 233         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 234                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 235
 236         /* Now try to remove the lock */
 237         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 238
 239         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 240         nlm_release_host(host);
 241         nlm_release_file(file);
 242         return rpc_success;
 243 }
 244
 245 /*
 246  * GRANTED: A server calls us to tell that a process' lock request
 247  * was granted
 248  */
 249 static __be32
 250 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 251                                             struct nlm_res  *resp)
 252 {
 253         resp->cookie = argp->cookie;
 254
 255         dprintk("lockd: GRANTED       called\n");
 256         resp->status = nlmclnt_grant(&rqstp->rq_addr, &argp->lock);
 257         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 258         return rpc_success;
 259 }
 260
 261 /*
 262  * This is the generic lockd callback for async RPC calls
 263  */
 264 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 265 {
 266         dprintk("lockd: %4d callback returned %d\n", task->tk_pid,
 267                         -task->tk_status);
 268 }
 269
 270 static void nlmsvc_callback_release(void *data)
 271 {
 272         nlm_release_call(data);
 273 }
 274
 275 static const struct rpc_call_ops nlmsvc_callback_ops = {
 276         .rpc_call_done = nlmsvc_callback_exit,
 277         .rpc_release = nlmsvc_callback_release,
 278 };
 279
 280 /*
 281  * `Async' versions of the above service routines. They aren't really,
 282  * because we send the callback before the reply proper. I hope this
 283  * doesn't break any clients.
 284  */
 285 static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 286                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 287 {
 288         struct nlm_host *host;
 289         struct nlm_rqst *call;
 290         __be32 stat;
 291
 292         host = nlmsvc_lookup_host(rqstp,
 293                                   argp->lock.caller,
 294                                   argp->lock.len);
 295         if (host == NULL)
 296                 return rpc_system_err;
 297
 298         call = nlm_alloc_call(host);
 299         if (call == NULL)
 300                 return rpc_system_err;
 301
 302         stat = func(rqstp, argp, &call->a_res);
 303         if (stat != 0) {
 304                 nlm_release_call(call);
 305                 return stat;
 306         }
 307
 308         call->a_flags = RPC_TASK_ASYNC;
 309         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 310                 return rpc_system_err;
 311         return rpc_success;
 312 }
 313
 314 static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 315                                              void            *resp)
 316 {
 317         dprintk("lockd: TEST_MSG      called\n");
 318         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 319 }
 320
 321 static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 322                                              void            *resp)
 323 {
 324         dprintk("lockd: LOCK_MSG      called\n");
 325         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 326 }
 327
 328 static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 329                                                void            *resp)
 330 {
 331         dprintk("lockd: CANCEL_MSG    called\n");
 332         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 333 }
 334
 335 static __be32
 336 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 337                                                void            *resp)
 338 {
 339         dprintk("lockd: UNLOCK_MSG    called\n");
 340         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 341 }
 342
 343 static __be32
 344 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 345                                                 void            *resp)
 346 {
 347         dprintk("lockd: GRANTED_MSG   called\n");
 348         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 349 }
 350
 351 /*
 352  * SHARE: create a DOS share or alter existing share.
 353  */
 354 static __be32
 355 nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 356                                           struct nlm_res  *resp)
 357 {
 358         struct nlm_host *host;
 359         struct nlm_file *file;
 360
 361         dprintk("lockd: SHARE         called\n");
 362
 363         resp->cookie = argp->cookie;
 364
 365         /* Don't accept new lock requests during grace period */
 366         if (nlmsvc_grace_period && !argp->reclaim) {
 367                 resp->status = nlm_lck_denied_grace_period;
 368                 return rpc_success;
 369         }
 370
 371         /* Obtain client and file */
 372         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 373                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 374
 375         /* Now try to create the share */
 376         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 377
 378         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 379         nlm_release_host(host);
 380         nlm_release_file(file);
 381         return rpc_success;
 382 }
 383
 384 /*
 385  * UNSHARE: Release a DOS share.
 386  */
 387 static __be32
 388 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 389                                             struct nlm_res  *resp)
 390 {
 391         struct nlm_host *host;
 392         struct nlm_file *file;
 393
 394         dprintk("lockd: UNSHARE       called\n");
 395
 396         resp->cookie = argp->cookie;
 397
 398         /* Don't accept requests during grace period */
 399         if (nlmsvc_grace_period) {
 400                 resp->status = nlm_lck_denied_grace_period;
 401                 return rpc_success;
 402         }
 403
 404         /* Obtain client and file */
 405         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 406                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 407
 408         /* Now try to unshare the file */
 409         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 410
 411         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 412         nlm_release_host(host);
 413         nlm_release_file(file);
 414         return rpc_success;
 415 }
 416
 417 /*
 418  * NM_LOCK: Create an unmonitored lock
 419  */
 420 static __be32
 421 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 422                                             struct nlm_res  *resp)
 423 {
 424         dprintk("lockd: NM_LOCK       called\n");
 425
 426         argp->monitor = 0;              /* just clean the monitor flag */
 427         return nlmsvc_proc_lock(rqstp, argp, resp);
 428 }
 429
 430 /*
 431  * FREE_ALL: Release all locks and shares held by client
 432  */
 433 static __be32
 434 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 435                                              void            *resp)
 436 {
 437         struct nlm_host *host;
 438
 439         /* Obtain client */
 440         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 441                 return rpc_success;
 442
 443         nlmsvc_free_host_resources(host);
 444         nlm_release_host(host);
 445         return rpc_success;
 446 }
 447
 448 /*
 449  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 450  */
 451 static __be32
 452 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 453                                               void              *resp)
 454 {
 455         struct sockaddr_in      saddr = rqstp->rq_addr;
 456
 457         dprintk("lockd: SM_NOTIFY     called\n");
 458         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 459          || ntohs(saddr.sin_port) >= 1024) {
 460                 printk(KERN_WARNING
 461                         "lockd: rejected NSM callback from %08x:%d\n",
 462                         ntohl(rqstp->rq_addr.sin_addr.s_addr),
 463                         ntohs(rqstp->rq_addr.sin_port));
 464                 return rpc_system_err;
 465         }
 466
 467         /* Obtain the host pointer for this NFS server and try to
 468          * reclaim all locks we hold on this server.
 469          */
 470         memset(&saddr, 0, sizeof(saddr));
 471         saddr.sin_addr.s_addr = argp->addr;
 472         nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
 473
 474         return rpc_success;
 475 }
 476
 477 /*
 478  * client sent a GRANTED_RES, let's remove the associated block
 479  */
 480 static __be32
 481 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 482                                                 void            *resp)
 483 {
 484         if (!nlmsvc_ops)
 485                 return rpc_success;
 486
 487         dprintk("lockd: GRANTED_RES   called\n");
 488
 489         nlmsvc_grant_reply(&argp->cookie, argp->status);
 490         return rpc_success;
 491 }
 492
 493 /*
 494  * NLM Server procedures.
 495  */
 496
 497 #define nlmsvc_encode_norep     nlmsvc_encode_void
 498 #define nlmsvc_decode_norep     nlmsvc_decode_void
 499 #define nlmsvc_decode_testres   nlmsvc_decode_void
 500 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 501 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 502 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 503 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 504
 505 #define nlmsvc_proc_none        nlmsvc_proc_null
 506 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 507 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 508 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 509 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 510
 511 struct nlm_void                 { int dummy; };
 512
 513 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 514  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 515    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 516    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 517    .pc_release  = NULL,                                 \
 518    .pc_argsize  = sizeof(struct nlm_##argt),            \
 519    .pc_ressize  = sizeof(struct nlm_##rest),            \
 520    .pc_xdrressize = respsize,                           \
 521  }
 522
 523 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 524 #define St      1                               /* status */
 525 #define No      (1+1024/4)                      /* Net Obj */
 526 #define Rg      2                               /* range - offset + size */
 527
 528 struct svc_procedure            nlmsvc_procedures[] = {
 529   PROC(null,            void,           void,           void,   void, 1),
 530   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 531   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 532   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 533   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 534   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 535   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 536   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 537   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 538   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 539   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 540   PROC(test_res,        testres,        norep,          res,    void, 1),
 541   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 542   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 543   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 544   PROC(granted_res,     res,            norep,          res,    void, 1),
 545   /* statd callback */
 546   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 547   PROC(none,            void,           void,           void,   void, 1),
 548   PROC(none,            void,           void,           void,   void, 1),
 549   PROC(none,            void,           void,           void,   void, 1),
 550   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 551   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 552   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 553   PROC(free_all,        notify,         void,           args,   void, 0),
 554
 555 };