fs/lockd/clntproc.c

   1 /*
   2  * linux/fs/lockd/clntproc.c
   3  *
   4  * RPC procedures for the client side NLM implementation
   5  *
   6  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #include <linux/config.h>
  10 #include <linux/types.h>
  11 #include <linux/errno.h>
  12 #include <linux/fs.h>
  13 #include <linux/nfs_fs.h>
  14 #include <linux/utsname.h>
  15 #include <linux/smp_lock.h>
  16 #include <linux/sunrpc/clnt.h>
  17 #include <linux/sunrpc/svc.h>
  18 #include <linux/lockd/lockd.h>
  19 #include <linux/lockd/sm_inter.h>
  20
  21 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  22 #define NLMCLNT_GRACE_WAIT      (5*HZ)
  23
  24 static int      nlmclnt_test(struct nlm_rqst *, struct file_lock *);
  25 static int      nlmclnt_lock(struct nlm_rqst *, struct file_lock *);
  26 static int      nlmclnt_unlock(struct nlm_rqst *, struct file_lock *);
  27 static void     nlmclnt_unlock_callback(struct rpc_task *);
  28 static void     nlmclnt_cancel_callback(struct rpc_task *);
  29 static int      nlm_stat_to_errno(u32 stat);
  30
  31 /*
  32  * Cookie counter for NLM requests
  33  */
  34 static u32      nlm_cookie = 0x1234;
  35
  36 static inline void nlmclnt_next_cookie(struct nlm_cookie *c)
  37 {
  38         memcpy(c->data, &nlm_cookie, 4);
  39         memset(c->data+4, 0, 4);
  40         c->len=4;
  41         nlm_cookie++;
  42 }
  43
  44 /*
  45  * Initialize arguments for TEST/LOCK/UNLOCK/CANCEL calls
  46  */
  47 static inline void
  48 nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl)
  49 {
  50         struct nlm_args *argp = &req->a_args;
  51         struct nlm_lock *lock = &argp->lock;
  52
  53         nlmclnt_next_cookie(&argp->cookie);
  54         argp->state   = nsm_local_state;
  55         memcpy(&lock->fh, NFS_FH(fl->fl_file->f_dentry->d_inode), sizeof(struct nfs_fh));
  56         lock->caller  = system_utsname.nodename;
  57         lock->oh.data = req->a_owner;
  58         lock->oh.len  = sprintf(req->a_owner, "%d@%s",
  59                                 current->pid, system_utsname.nodename);
  60         locks_copy_lock(&lock->fl, fl);
  61 }
  62
  63 /*
  64  * Initialize arguments for GRANTED call. The nlm_rqst structure
  65  * has been cleared already.
  66  */
  67 int
  68 nlmclnt_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock)
  69 {
  70         locks_copy_lock(&call->a_args.lock.fl, &lock->fl);
  71         memcpy(&call->a_args.lock.fh, &lock->fh, sizeof(call->a_args.lock.fh));
  72         call->a_args.lock.caller = system_utsname.nodename;
  73         call->a_args.lock.oh.len = lock->oh.len;
  74
  75         /* set default data area */
  76         call->a_args.lock.oh.data = call->a_owner;
  77
  78         if (lock->oh.len > NLMCLNT_OHSIZE) {
  79                 void *data = kmalloc(lock->oh.len, GFP_KERNEL);
  80                 if (!data)
  81                         return 0;
  82                 call->a_args.lock.oh.data = (u8 *) data;
  83         }
  84
  85         memcpy(call->a_args.lock.oh.data, lock->oh.data, lock->oh.len);
  86         return 1;
  87 }
  88
  89 void
  90 nlmclnt_freegrantargs(struct nlm_rqst *call)
  91 {
  92         /*
  93          * Check whether we allocated memory for the owner.
  94          */
  95         if (call->a_args.lock.oh.data != (u8 *) call->a_owner) {
  96                 kfree(call->a_args.lock.oh.data);
  97         }
  98 }
  99
 100 /*
 101  * This is the main entry point for the NLM client.
 102  */
 103 int
 104 nlmclnt_proc(struct inode *inode, int cmd, struct file_lock *fl)
 105 {
 106         struct nfs_server       *nfssrv = NFS_SERVER(inode);
 107         struct nlm_host         *host;
 108         struct nlm_rqst         reqst, *call = &reqst;
 109         sigset_t                oldset;
 110         unsigned long           flags;
 111         int                     status, proto, vers;
 112
 113         vers = (NFS_PROTO(inode)->version == 3) ? 4 : 1;
 114         if (NFS_PROTO(inode)->version > 3) {
 115                 printk(KERN_NOTICE "NFSv4 file locking not implemented!\n");
 116                 return -ENOLCK;
 117         }
 118
 119         /* Retrieve transport protocol from NFS client */
 120         proto = NFS_CLIENT(inode)->cl_xprt->prot;
 121
 122         if (!(host = nlmclnt_lookup_host(NFS_ADDR(inode), proto, vers)))
 123                 return -ENOLCK;
 124
 125         /* Create RPC client handle if not there, and copy soft
 126          * and intr flags from NFS client. */
 127         if (host->h_rpcclnt == NULL) {
 128                 struct rpc_clnt *clnt;
 129
 130                 /* Bind an rpc client to this host handle (does not
 131                  * perform a portmapper lookup) */
 132                 if (!(clnt = nlm_bind_host(host))) {
 133                         status = -ENOLCK;
 134                         goto done;
 135                 }
 136                 clnt->cl_softrtry = nfssrv->client->cl_softrtry;
 137                 clnt->cl_intr     = nfssrv->client->cl_intr;
 138                 clnt->cl_chatty   = nfssrv->client->cl_chatty;
 139         }
 140
 141         /* Keep the old signal mask */
 142         spin_lock_irqsave(&current->sighand->siglock, flags);
 143         oldset = current->blocked;
 144
 145         /* If we're cleaning up locks because the process is exiting,
 146          * perform the RPC call asynchronously. */
 147         if ((IS_SETLK(cmd) || IS_SETLKW(cmd))
 148             && fl->fl_type == F_UNLCK
 149             && (current->flags & PF_EXITING)) {
 150                 sigfillset(&current->blocked);  /* Mask all signals */
 151                 recalc_sigpending();
 152                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 153
 154                 call = nlmclnt_alloc_call();
 155                 if (!call) {
 156                         status = -ENOMEM;
 157                         goto out_restore;
 158                 }
 159                 call->a_flags = RPC_TASK_ASYNC;
 160         } else {
 161                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 162                 memset(call, 0, sizeof(*call));
 163                 locks_init_lock(&call->a_args.lock.fl);
 164                 locks_init_lock(&call->a_res.lock.fl);
 165         }
 166         call->a_host = host;
 167
 168         /* Set up the argument struct */
 169         nlmclnt_setlockargs(call, fl);
 170
 171         if (IS_SETLK(cmd) || IS_SETLKW(cmd)) {
 172                 if (fl->fl_type != F_UNLCK) {
 173                         call->a_args.block = IS_SETLKW(cmd) ? 1 : 0;
 174                         status = nlmclnt_lock(call, fl);
 175                 } else
 176                         status = nlmclnt_unlock(call, fl);
 177         } else if (IS_GETLK(cmd))
 178                 status = nlmclnt_test(call, fl);
 179         else
 180                 status = -EINVAL;
 181
 182         if (status < 0 && (call->a_flags & RPC_TASK_ASYNC))
 183                 kfree(call);
 184
 185  out_restore:
 186         spin_lock_irqsave(&current->sighand->siglock, flags);
 187         current->blocked = oldset;
 188         recalc_sigpending();
 189         spin_unlock_irqrestore(&current->sighand->siglock, flags);
 190
 191 done:
 192         dprintk("lockd: clnt proc returns %d\n", status);
 193         nlm_release_host(host);
 194         return status;
 195 }
 196
 197 /*
 198  * Wait while server is in grace period
 199  */
 200 static inline int
 201 nlmclnt_grace_wait(struct nlm_host *host)
 202 {
 203         if (!host->h_reclaiming)
 204                 interruptible_sleep_on_timeout(&host->h_gracewait, 10*HZ);
 205         else
 206                 interruptible_sleep_on(&host->h_gracewait);
 207         return signalled()? -ERESTARTSYS : 0;
 208 }
 209
 210 /*
 211  * Allocate an NLM RPC call struct
 212  */
 213 struct nlm_rqst *
 214 nlmclnt_alloc_call(void)
 215 {
 216         struct nlm_rqst *call;
 217
 218         while (!signalled()) {
 219                 call = (struct nlm_rqst *) kmalloc(sizeof(struct nlm_rqst), GFP_KERNEL);
 220                 if (call) {
 221                         memset(call, 0, sizeof(*call));
 222                         locks_init_lock(&call->a_args.lock.fl);
 223                         locks_init_lock(&call->a_res.lock.fl);
 224                         return call;
 225                 }
 226                 printk("nlmclnt_alloc_call: failed, waiting for memory\n");
 227                 current->state = TASK_INTERRUPTIBLE;
 228                 schedule_timeout(5*HZ);
 229         }
 230         return NULL;
 231 }
 232
 233 /*
 234  * Generic NLM call
 235  */
 236 int
 237 nlmclnt_call(struct nlm_rqst *req, u32 proc)
 238 {
 239         struct nlm_host *host = req->a_host;
 240         struct rpc_clnt *clnt;
 241         struct nlm_args *argp = &req->a_args;
 242         struct nlm_res  *resp = &req->a_res;
 243         struct file     *filp = argp->lock.fl.fl_file;
 244         struct rpc_message msg = {
 245                 .rpc_argp       = argp,
 246                 .rpc_resp       = resp,
 247         };
 248         int             status;
 249
 250         dprintk("lockd: call procedure %d on %s\n",
 251                         (int)proc, host->h_name);
 252
 253         if (filp)
 254                 msg.rpc_cred = nfs_file_cred(filp);
 255
 256         do {
 257                 if (host->h_reclaiming && !argp->reclaim) {
 258                         interruptible_sleep_on(&host->h_gracewait);
 259                         continue;
 260                 }
 261
 262                 /* If we have no RPC client yet, create one. */
 263                 if ((clnt = nlm_bind_host(host)) == NULL)
 264                         return -ENOLCK;
 265                 msg.rpc_proc = &clnt->cl_procinfo[proc];
 266
 267                 /* Perform the RPC call. If an error occurs, try again */
 268                 if ((status = rpc_call_sync(clnt, &msg, 0)) < 0) {
 269                         dprintk("lockd: rpc_call returned error %d\n", -status);
 270                         switch (status) {
 271                         case -EPROTONOSUPPORT:
 272                                 status = -EINVAL;
 273                                 break;
 274                         case -ECONNREFUSED:
 275                         case -ETIMEDOUT:
 276                         case -ENOTCONN:
 277                                 nlm_rebind_host(host);
 278                                 status = -EAGAIN;
 279                                 break;
 280                         case -ERESTARTSYS:
 281                                 return signalled () ? -EINTR : status;
 282                         default:
 283                                 break;
 284                         }
 285                         break;
 286                 } else
 287                 if (resp->status == NLM_LCK_DENIED_GRACE_PERIOD) {
 288                         dprintk("lockd: server in grace period\n");
 289                         if (argp->reclaim) {
 290                                 printk(KERN_WARNING
 291                                      "lockd: spurious grace period reject?!\n");
 292                                 return -ENOLCK;
 293                         }
 294                 } else {
 295                         dprintk("lockd: server returns status %d\n", resp->status);
 296                         return 0;       /* Okay, call complete */
 297                 }
 298
 299                 /* Back off a little and try again */
 300                 interruptible_sleep_on_timeout(&host->h_gracewait, 15*HZ);
 301
 302                 /* When the lock requested by F_SETLKW isn't available,
 303                    we will wait until the request can be satisfied. If
 304                    a signal is received during wait, we should return
 305                    -EINTR. */
 306                 if (signalled ()) {
 307                         status = -EINTR;
 308                         break;
 309                 }
 310         } while (1);
 311
 312         return status;
 313 }
 314
 315 /*
 316  * Generic NLM call, async version.
 317  */
 318 int
 319 nlmsvc_async_call(struct nlm_rqst *req, u32 proc, rpc_action callback)
 320 {
 321         struct nlm_host *host = req->a_host;
 322         struct rpc_clnt *clnt;
 323         struct rpc_message msg = {
 324                 .rpc_argp       = &req->a_args,
 325                 .rpc_resp       = &req->a_res,
 326         };
 327         int             status;
 328
 329         dprintk("lockd: call procedure %d on %s (async)\n",
 330                         (int)proc, host->h_name);
 331
 332         /* If we have no RPC client yet, create one. */
 333         if ((clnt = nlm_bind_host(host)) == NULL)
 334                 return -ENOLCK;
 335         msg.rpc_proc = &clnt->cl_procinfo[proc];
 336
 337         /* bootstrap and kick off the async RPC call */
 338         status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, callback, req);
 339
 340         return status;
 341 }
 342
 343 int
 344 nlmclnt_async_call(struct nlm_rqst *req, u32 proc, rpc_action callback)
 345 {
 346         struct nlm_host *host = req->a_host;
 347         struct rpc_clnt *clnt;
 348         struct nlm_args *argp = &req->a_args;
 349         struct nlm_res  *resp = &req->a_res;
 350         struct file     *file = argp->lock.fl.fl_file;
 351         struct rpc_message msg = {
 352                 .rpc_argp       = argp,
 353                 .rpc_resp       = resp,
 354         };
 355         int             status;
 356
 357         dprintk("lockd: call procedure %d on %s (async)\n",
 358                         (int)proc, host->h_name);
 359
 360         /* If we have no RPC client yet, create one. */
 361         if ((clnt = nlm_bind_host(host)) == NULL)
 362                 return -ENOLCK;
 363         msg.rpc_proc = &clnt->cl_procinfo[proc];
 364
 365         /* bootstrap and kick off the async RPC call */
 366         if (file)
 367                 msg.rpc_cred = nfs_file_cred(file);
 368         /* Increment host refcount */
 369         nlm_get_host(host);
 370         status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, callback, req);
 371         if (status < 0)
 372                 nlm_release_host(host);
 373         return status;
 374 }
 375
 376 /*
 377  * TEST for the presence of a conflicting lock
 378  */
 379 static int
 380 nlmclnt_test(struct nlm_rqst *req, struct file_lock *fl)
 381 {
 382         int     status;
 383
 384         if ((status = nlmclnt_call(req, NLMPROC_TEST)) < 0)
 385                 return status;
 386
 387         status = req->a_res.status;
 388         if (status == NLM_LCK_GRANTED) {
 389                 fl->fl_type = F_UNLCK;
 390         } if (status == NLM_LCK_DENIED) {
 391                 /*
 392                  * Report the conflicting lock back to the application.
 393                  * FIXME: Is it OK to report the pid back as well?
 394                  */
 395                 locks_copy_lock(fl, &req->a_res.lock.fl);
 396                 /* fl->fl_pid = 0; */
 397         } else {
 398                 return nlm_stat_to_errno(req->a_res.status);
 399         }
 400
 401         return 0;
 402 }
 403
 404 static
 405 void nlmclnt_insert_lock_callback(struct file_lock *fl)
 406 {
 407         nlm_get_host(fl->fl_u.nfs_fl.host);
 408 }
 409 static
 410 void nlmclnt_remove_lock_callback(struct file_lock *fl)
 411 {
 412         if (fl->fl_u.nfs_fl.host) {
 413                 nlm_release_host(fl->fl_u.nfs_fl.host);
 414                 fl->fl_u.nfs_fl.host = NULL;
 415         }
 416 }
 417
 418 /*
 419  * LOCK: Try to create a lock
 420  *
 421  *                      Programmer Harassment Alert
 422  *
 423  * When given a blocking lock request in a sync RPC call, the HPUX lockd
 424  * will faithfully return LCK_BLOCKED but never cares to notify us when
 425  * the lock could be granted. This way, our local process could hang
 426  * around forever waiting for the callback.
 427  *
 428  *  Solution A: Implement busy-waiting
 429  *  Solution B: Use the async version of the call (NLM_LOCK_{MSG,RES})
 430  *
 431  * For now I am implementing solution A, because I hate the idea of
 432  * re-implementing lockd for a third time in two months. The async
 433  * calls shouldn't be too hard to do, however.
 434  *
 435  * This is one of the lovely things about standards in the NFS area:
 436  * they're so soft and squishy you can't really blame HP for doing this.
 437  */
 438 static int
 439 nlmclnt_lock(struct nlm_rqst *req, struct file_lock *fl)
 440 {
 441         struct nlm_host *host = req->a_host;
 442         struct nlm_res  *resp = &req->a_res;
 443         int             status;
 444
 445         if (!host->h_monitored && nsm_monitor(host) < 0) {
 446                 printk(KERN_NOTICE "lockd: failed to monitor %s\n",
 447                                         host->h_name);
 448                 return -ENOLCK;
 449         }
 450
 451         do {
 452                 if ((status = nlmclnt_call(req, NLMPROC_LOCK)) >= 0) {
 453                         if (resp->status != NLM_LCK_BLOCKED)
 454                                 break;
 455                         status = nlmclnt_block(host, fl, &resp->status);
 456                 }
 457                 if (status < 0)
 458                         return status;
 459         } while (resp->status == NLM_LCK_BLOCKED);
 460
 461         if (resp->status == NLM_LCK_GRANTED) {
 462                 fl->fl_u.nfs_fl.state = host->h_state;
 463                 fl->fl_u.nfs_fl.flags |= NFS_LCK_GRANTED;
 464                 fl->fl_u.nfs_fl.host = host;
 465                 fl->fl_insert = nlmclnt_insert_lock_callback;
 466                 fl->fl_remove = nlmclnt_remove_lock_callback;
 467         }
 468
 469         return nlm_stat_to_errno(resp->status);
 470 }
 471
 472 /*
 473  * RECLAIM: Try to reclaim a lock
 474  */
 475 int
 476 nlmclnt_reclaim(struct nlm_host *host, struct file_lock *fl)
 477 {
 478         struct nlm_rqst reqst, *req;
 479         int             status;
 480
 481         req = &reqst;
 482         memset(req, 0, sizeof(*req));
 483         locks_init_lock(&req->a_args.lock.fl);
 484         locks_init_lock(&req->a_res.lock.fl);
 485         req->a_host  = host;
 486         req->a_flags = 0;
 487
 488         /* Set up the argument struct */
 489         nlmclnt_setlockargs(req, fl);
 490         req->a_args.reclaim = 1;
 491
 492         if ((status = nlmclnt_call(req, NLMPROC_LOCK)) >= 0
 493          && req->a_res.status == NLM_LCK_GRANTED)
 494                 return 0;
 495
 496         printk(KERN_WARNING "lockd: failed to reclaim lock for pid %d "
 497                                 "(errno %d, status %d)\n", fl->fl_pid,
 498                                 status, req->a_res.status);
 499
 500         /*
 501          * FIXME: This is a serious failure. We can
 502          *
 503          *  a.  Ignore the problem
 504          *  b.  Send the owning process some signal (Linux doesn't have
 505          *      SIGLOST, though...)
 506          *  c.  Retry the operation
 507          *
 508          * Until someone comes up with a simple implementation
 509          * for b or c, I'll choose option a.
 510          */
 511
 512         return -ENOLCK;
 513 }
 514
 515 /*
 516  * UNLOCK: remove an existing lock
 517  */
 518 static int
 519 nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
 520 {
 521         struct nlm_res  *resp = &req->a_res;
 522         int             status;
 523
 524         /* Clean the GRANTED flag now so the lock doesn't get
 525          * reclaimed while we're stuck in the unlock call. */
 526         fl->fl_u.nfs_fl.flags &= ~NFS_LCK_GRANTED;
 527
 528         if (req->a_flags & RPC_TASK_ASYNC) {
 529                 return nlmclnt_async_call(req, NLMPROC_UNLOCK,
 530                                         nlmclnt_unlock_callback);
 531         }
 532
 533         if ((status = nlmclnt_call(req, NLMPROC_UNLOCK)) < 0)
 534                 return status;
 535
 536         if (resp->status == NLM_LCK_GRANTED)
 537                 return 0;
 538
 539         if (resp->status != NLM_LCK_DENIED_NOLOCKS)
 540                 printk("lockd: unexpected unlock status: %d\n", resp->status);
 541
 542         /* What to do now? I'm out of my depth... */
 543
 544         return -ENOLCK;
 545 }
 546
 547 static void
 548 nlmclnt_unlock_callback(struct rpc_task *task)
 549 {
 550         struct nlm_rqst *req = (struct nlm_rqst *) task->tk_calldata;
 551         int             status = req->a_res.status;
 552
 553         if (RPC_ASSASSINATED(task))
 554                 goto die;
 555
 556         if (task->tk_status < 0) {
 557                 dprintk("lockd: unlock failed (err = %d)\n", -task->tk_status);
 558                 goto retry_rebind;
 559         }
 560         if (status == NLM_LCK_DENIED_GRACE_PERIOD) {
 561                 rpc_delay(task, NLMCLNT_GRACE_WAIT);
 562                 goto retry_unlock;
 563         }
 564         if (status != NLM_LCK_GRANTED)
 565                 printk(KERN_WARNING "lockd: unexpected unlock status: %d\n", status);
 566
 567 die:
 568         nlm_release_host(req->a_host);
 569         kfree(req);
 570         return;
 571  retry_rebind:
 572         nlm_rebind_host(req->a_host);
 573  retry_unlock:
 574         rpc_restart_call(task);
 575 }
 576
 577 /*
 578  * Cancel a blocked lock request.
 579  * We always use an async RPC call for this in order not to hang a
 580  * process that has been Ctrl-C'ed.
 581  */
 582 int
 583 nlmclnt_cancel(struct nlm_host *host, struct file_lock *fl)
 584 {
 585         struct nlm_rqst *req;
 586         unsigned long   flags;
 587         sigset_t        oldset;
 588         int             status;
 589
 590         /* Block all signals while setting up call */
 591         spin_lock_irqsave(&current->sighand->siglock, flags);
 592         oldset = current->blocked;
 593         sigfillset(&current->blocked);
 594         recalc_sigpending();
 595         spin_unlock_irqrestore(&current->sighand->siglock, flags);
 596
 597         req = nlmclnt_alloc_call();
 598         if (!req)
 599                 return -ENOMEM;
 600         req->a_host  = host;
 601         req->a_flags = RPC_TASK_ASYNC;
 602
 603         nlmclnt_setlockargs(req, fl);
 604
 605         status = nlmclnt_async_call(req, NLMPROC_CANCEL,
 606                                         nlmclnt_cancel_callback);
 607         if (status < 0)
 608                 kfree(req);
 609
 610         spin_lock_irqsave(&current->sighand->siglock, flags);
 611         current->blocked = oldset;
 612         recalc_sigpending();
 613         spin_unlock_irqrestore(&current->sighand->siglock, flags);
 614
 615         return status;
 616 }
 617
 618 static void
 619 nlmclnt_cancel_callback(struct rpc_task *task)
 620 {
 621         struct nlm_rqst *req = (struct nlm_rqst *) task->tk_calldata;
 622
 623         if (RPC_ASSASSINATED(task))
 624                 goto die;
 625
 626         if (task->tk_status < 0) {
 627                 dprintk("lockd: CANCEL call error %d, retrying.\n",
 628                                         task->tk_status);
 629                 goto retry_cancel;
 630         }
 631
 632         dprintk("lockd: cancel status %d (task %d)\n",
 633                         req->a_res.status, task->tk_pid);
 634
 635         switch (req->a_res.status) {
 636         case NLM_LCK_GRANTED:
 637         case NLM_LCK_DENIED_GRACE_PERIOD:
 638                 /* Everything's good */
 639                 break;
 640         case NLM_LCK_DENIED_NOLOCKS:
 641                 dprintk("lockd: CANCEL failed (server has no locks)\n");
 642                 goto retry_cancel;
 643         default:
 644                 printk(KERN_NOTICE "lockd: weird return %d for CANCEL call\n",
 645                         req->a_res.status);
 646         }
 647
 648 die:
 649         nlm_release_host(req->a_host);
 650         kfree(req);
 651         return;
 652
 653 retry_cancel:
 654         nlm_rebind_host(req->a_host);
 655         rpc_restart_call(task);
 656         rpc_delay(task, 30 * HZ);
 657 }
 658
 659 /*
 660  * Convert an NLM status code to a generic kernel errno
 661  */
 662 static int
 663 nlm_stat_to_errno(u32 status)
 664 {
 665         switch(status) {
 666         case NLM_LCK_GRANTED:
 667                 return 0;
 668         case NLM_LCK_DENIED:
 669                 return -EAGAIN;
 670         case NLM_LCK_DENIED_NOLOCKS:
 671         case NLM_LCK_DENIED_GRACE_PERIOD:
 672                 return -ENOLCK;
 673         case NLM_LCK_BLOCKED:
 674                 printk(KERN_NOTICE "lockd: unexpected status NLM_BLOCKED\n");
 675                 return -ENOLCK;
 676 #ifdef CONFIG_LOCKD_V4
 677         case NLM_DEADLCK:
 678                 return -EDEADLK;
 679         case NLM_ROFS:
 680                 return -EROFS;
 681         case NLM_STALE_FH:
 682                 return -ESTALE;
 683         case NLM_FBIG:
 684                 return -EOVERFLOW;
 685         case NLM_FAILED:
 686                 return -ENOLCK;
 687 #endif
 688         }
 689         printk(KERN_NOTICE "lockd: unexpected server status %d\n", status);
 690         return -ENOLCK;
 691 }