fs/lockd/svc4proc.c

   1 /*
   2  * linux/fs/lockd/svc4proc.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/lockd/lockd.h>
  13 #include <linux/lockd/share.h>
  14
  15 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  16
  17 /*
  18  * Obtain client and file from arguments
  19  */
  20 static __be32
  21 nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  22                         struct nlm_host **hostp, struct nlm_file **filp)
  23 {
  24         struct nlm_host         *host = NULL;
  25         struct nlm_file         *file = NULL;
  26         struct nlm_lock         *lock = &argp->lock;
  27         __be32                  error = 0;
  28
  29         /* nfsd callbacks must have been installed for this procedure */
  30         if (!nlmsvc_ops)
  31                 return nlm_lck_denied_nolocks;
  32
  33         /* Obtain host handle */
  34         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  35          || (argp->monitor && nsm_monitor(host) < 0))
  36                 goto no_locks;
  37         *hostp = host;
  38
  39         /* Obtain file pointer. Not used by FREE_ALL call. */
  40         if (filp != NULL) {
  41                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  42                         goto no_locks;
  43                 *filp = file;
  44
  45                 /* Set up the missing parts of the file_lock structure */
  46                 lock->fl.fl_file  = file->f_file;
  47                 lock->fl.fl_owner = (fl_owner_t) host;
  48                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  49         }
  50
  51         return 0;
  52
  53 no_locks:
  54         nlmsvc_release_host(host);
  55         if (error)
  56                 return error;
  57         return nlm_lck_denied_nolocks;
  58 }
  59
  60 /*
  61  * NULL: Test for presence of service
  62  */
  63 static __be32
  64 nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  65 {
  66         dprintk("lockd: NULL          called\n");
  67         return rpc_success;
  68 }
  69
  70 /*
  71  * TEST: Check for conflicting lock
  72  */
  73 static __be32
  74 nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
  75                                          struct nlm_res  *resp)
  76 {
  77         struct nlm_host *host;
  78         struct nlm_file *file;
  79         __be32 rc = rpc_success;
  80
  81         dprintk("lockd: TEST4        called\n");
  82         resp->cookie = argp->cookie;
  83
  84         /* Obtain client and file */
  85         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  86                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  87
  88         /* Now check for conflicting locks */
  89         resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
  90         if (resp->status == nlm_drop_reply)
  91                 rc = rpc_drop_reply;
  92         else
  93                 dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
  94
  95         nlmsvc_release_host(host);
  96         nlm_release_file(file);
  97         return rc;
  98 }
  99
 100 static __be32
 101 nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 102                                          struct nlm_res  *resp)
 103 {
 104         struct nlm_host *host;
 105         struct nlm_file *file;
 106         __be32 rc = rpc_success;
 107
 108         dprintk("lockd: LOCK          called\n");
 109
 110         resp->cookie = argp->cookie;
 111
 112         /* Obtain client and file */
 113         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 114                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 115
 116 #if 0
 117         /* If supplied state doesn't match current state, we assume it's
 118          * an old request that time-warped somehow. Any error return would
 119          * do in this case because it's irrelevant anyway.
 120          *
 121          * NB: We don't retrieve the remote host's state yet.
 122          */
 123         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 124                 resp->status = nlm_lck_denied_nolocks;
 125         } else
 126 #endif
 127
 128         /* Now try to lock the file */
 129         resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
 130                                         argp->block, &argp->cookie,
 131                                         argp->reclaim);
 132         if (resp->status == nlm_drop_reply)
 133                 rc = rpc_drop_reply;
 134         else
 135                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 136
 137         nlmsvc_release_host(host);
 138         nlm_release_file(file);
 139         return rc;
 140 }
 141
 142 static __be32
 143 nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 144                                            struct nlm_res  *resp)
 145 {
 146         struct nlm_host *host;
 147         struct nlm_file *file;
 148
 149         dprintk("lockd: CANCEL        called\n");
 150
 151         resp->cookie = argp->cookie;
 152
 153         /* Don't accept requests during grace period */
 154         if (locks_in_grace()) {
 155                 resp->status = nlm_lck_denied_grace_period;
 156                 return rpc_success;
 157         }
 158
 159         /* Obtain client and file */
 160         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 161                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 162
 163         /* Try to cancel request. */
 164         resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
 165
 166         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 167         nlmsvc_release_host(host);
 168         nlm_release_file(file);
 169         return rpc_success;
 170 }
 171
 172 /*
 173  * UNLOCK: release a lock
 174  */
 175 static __be32
 176 nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 177                                            struct nlm_res  *resp)
 178 {
 179         struct nlm_host *host;
 180         struct nlm_file *file;
 181
 182         dprintk("lockd: UNLOCK        called\n");
 183
 184         resp->cookie = argp->cookie;
 185
 186         /* Don't accept new lock requests during grace period */
 187         if (locks_in_grace()) {
 188                 resp->status = nlm_lck_denied_grace_period;
 189                 return rpc_success;
 190         }
 191
 192         /* Obtain client and file */
 193         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 194                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 195
 196         /* Now try to remove the lock */
 197         resp->status = nlmsvc_unlock(file, &argp->lock);
 198
 199         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 200         nlmsvc_release_host(host);
 201         nlm_release_file(file);
 202         return rpc_success;
 203 }
 204
 205 /*
 206  * GRANTED: A server calls us to tell that a process' lock request
 207  * was granted
 208  */
 209 static __be32
 210 nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 211                                             struct nlm_res  *resp)
 212 {
 213         resp->cookie = argp->cookie;
 214
 215         dprintk("lockd: GRANTED       called\n");
 216         resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
 217         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 218         return rpc_success;
 219 }
 220
 221 /*
 222  * This is the generic lockd callback for async RPC calls
 223  */
 224 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 225 {
 226         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 227                         -task->tk_status);
 228 }
 229
 230 static void nlm4svc_callback_release(void *data)
 231 {
 232         nlmsvc_release_call(data);
 233 }
 234
 235 static const struct rpc_call_ops nlm4svc_callback_ops = {
 236         .rpc_call_done = nlm4svc_callback_exit,
 237         .rpc_release = nlm4svc_callback_release,
 238 };
 239
 240 /*
 241  * `Async' versions of the above service routines. They aren't really,
 242  * because we send the callback before the reply proper. I hope this
 243  * doesn't break any clients.
 244  */
 245 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 246                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 247 {
 248         struct nlm_host *host;
 249         struct nlm_rqst *call;
 250         __be32 stat;
 251
 252         host = nlmsvc_lookup_host(rqstp,
 253                                   argp->lock.caller,
 254                                   argp->lock.len);
 255         if (host == NULL)
 256                 return rpc_system_err;
 257
 258         call = nlm_alloc_call(host);
 259         if (call == NULL)
 260                 return rpc_system_err;
 261
 262         stat = func(rqstp, argp, &call->a_res);
 263         if (stat != 0) {
 264                 nlmsvc_release_call(call);
 265                 return stat;
 266         }
 267
 268         call->a_flags = RPC_TASK_ASYNC;
 269         if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
 270                 return rpc_system_err;
 271         return rpc_success;
 272 }
 273
 274 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 275                                              void            *resp)
 276 {
 277         dprintk("lockd: TEST_MSG      called\n");
 278         return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
 279 }
 280
 281 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 282                                              void            *resp)
 283 {
 284         dprintk("lockd: LOCK_MSG      called\n");
 285         return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
 286 }
 287
 288 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 289                                                void            *resp)
 290 {
 291         dprintk("lockd: CANCEL_MSG    called\n");
 292         return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
 293 }
 294
 295 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 296                                                void            *resp)
 297 {
 298         dprintk("lockd: UNLOCK_MSG    called\n");
 299         return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
 300 }
 301
 302 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 303                                                 void            *resp)
 304 {
 305         dprintk("lockd: GRANTED_MSG   called\n");
 306         return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
 307 }
 308
 309 /*
 310  * SHARE: create a DOS share or alter existing share.
 311  */
 312 static __be32
 313 nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 314                                           struct nlm_res  *resp)
 315 {
 316         struct nlm_host *host;
 317         struct nlm_file *file;
 318
 319         dprintk("lockd: SHARE         called\n");
 320
 321         resp->cookie = argp->cookie;
 322
 323         /* Don't accept new lock requests during grace period */
 324         if (locks_in_grace() && !argp->reclaim) {
 325                 resp->status = nlm_lck_denied_grace_period;
 326                 return rpc_success;
 327         }
 328
 329         /* Obtain client and file */
 330         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 331                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 332
 333         /* Now try to create the share */
 334         resp->status = nlmsvc_share_file(host, file, argp);
 335
 336         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 337         nlmsvc_release_host(host);
 338         nlm_release_file(file);
 339         return rpc_success;
 340 }
 341
 342 /*
 343  * UNSHARE: Release a DOS share.
 344  */
 345 static __be32
 346 nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 347                                             struct nlm_res  *resp)
 348 {
 349         struct nlm_host *host;
 350         struct nlm_file *file;
 351
 352         dprintk("lockd: UNSHARE       called\n");
 353
 354         resp->cookie = argp->cookie;
 355
 356         /* Don't accept requests during grace period */
 357         if (locks_in_grace()) {
 358                 resp->status = nlm_lck_denied_grace_period;
 359                 return rpc_success;
 360         }
 361
 362         /* Obtain client and file */
 363         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 364                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 365
 366         /* Now try to lock the file */
 367         resp->status = nlmsvc_unshare_file(host, file, argp);
 368
 369         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 370         nlmsvc_release_host(host);
 371         nlm_release_file(file);
 372         return rpc_success;
 373 }
 374
 375 /*
 376  * NM_LOCK: Create an unmonitored lock
 377  */
 378 static __be32
 379 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 380                                             struct nlm_res  *resp)
 381 {
 382         dprintk("lockd: NM_LOCK       called\n");
 383
 384         argp->monitor = 0;              /* just clean the monitor flag */
 385         return nlm4svc_proc_lock(rqstp, argp, resp);
 386 }
 387
 388 /*
 389  * FREE_ALL: Release all locks and shares held by client
 390  */
 391 static __be32
 392 nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 393                                              void            *resp)
 394 {
 395         struct nlm_host *host;
 396
 397         /* Obtain client */
 398         if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
 399                 return rpc_success;
 400
 401         nlmsvc_free_host_resources(host);
 402         nlmsvc_release_host(host);
 403         return rpc_success;
 404 }
 405
 406 /*
 407  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 408  */
 409 static __be32
 410 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 411                                               void              *resp)
 412 {
 413         dprintk("lockd: SM_NOTIFY     called\n");
 414
 415         if (!nlm_privileged_requester(rqstp)) {
 416                 char buf[RPC_MAX_ADDRBUFLEN];
 417                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 418                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 419                 return rpc_system_err;
 420         }
 421
 422         nlm_host_rebooted(argp);
 423         return rpc_success;
 424 }
 425
 426 /*
 427  * client sent a GRANTED_RES, let's remove the associated block
 428  */
 429 static __be32
 430 nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 431                                                 void            *resp)
 432 {
 433         if (!nlmsvc_ops)
 434                 return rpc_success;
 435
 436         dprintk("lockd: GRANTED_RES   called\n");
 437
 438         nlmsvc_grant_reply(&argp->cookie, argp->status);
 439         return rpc_success;
 440 }
 441
 442
 443 /*
 444  * NLM Server procedures.
 445  */
 446
 447 #define nlm4svc_encode_norep    nlm4svc_encode_void
 448 #define nlm4svc_decode_norep    nlm4svc_decode_void
 449 #define nlm4svc_decode_testres  nlm4svc_decode_void
 450 #define nlm4svc_decode_lockres  nlm4svc_decode_void
 451 #define nlm4svc_decode_unlockres        nlm4svc_decode_void
 452 #define nlm4svc_decode_cancelres        nlm4svc_decode_void
 453 #define nlm4svc_decode_grantedres       nlm4svc_decode_void
 454
 455 #define nlm4svc_proc_none       nlm4svc_proc_null
 456 #define nlm4svc_proc_test_res   nlm4svc_proc_null
 457 #define nlm4svc_proc_lock_res   nlm4svc_proc_null
 458 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
 459 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
 460
 461 struct nlm_void                 { int dummy; };
 462
 463 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 464  { .pc_func     = (svc_procfunc) nlm4svc_proc_##name,   \
 465    .pc_decode   = (kxdrproc_t) nlm4svc_decode_##xargt,  \
 466    .pc_encode   = (kxdrproc_t) nlm4svc_encode_##xrest,  \
 467    .pc_release  = NULL,                                 \
 468    .pc_argsize  = sizeof(struct nlm_##argt),            \
 469    .pc_ressize  = sizeof(struct nlm_##rest),            \
 470    .pc_xdrressize = respsize,                           \
 471  }
 472 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 473 #define No      (1+1024/4)                              /* netobj */
 474 #define St      1                                       /* status */
 475 #define Rg      4                                       /* range (offset + length) */
 476 struct svc_procedure            nlmsvc_procedures4[] = {
 477   PROC(null,            void,           void,           void,   void, 1),
 478   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 479   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 480   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 481   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 482   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 483   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 484   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 485   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 486   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 487   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 488   PROC(test_res,        testres,        norep,          res,    void, 1),
 489   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 490   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 491   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 492   PROC(granted_res,     res,            norep,          res,    void, 1),
 493   /* statd callback */
 494   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 495   PROC(none,            void,           void,           void,   void, 0),
 496   PROC(none,            void,           void,           void,   void, 0),
 497   PROC(none,            void,           void,           void,   void, 0),
 498   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 499   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 500   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 501   PROC(free_all,        notify,         void,           args,   void, 1),
 502
 503 };