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 #include <linux/sunrpc/svc_xprt.h>
  15
  16 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  17
  18 /*
  19  * Obtain client and file from arguments
  20  */
  21 static __be32
  22 nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  23                         struct nlm_host **hostp, struct nlm_file **filp)
  24 {
  25         struct nlm_host         *host = NULL;
  26         struct nlm_file         *file = NULL;
  27         struct nlm_lock         *lock = &argp->lock;
  28         __be32                  error = 0;
  29
  30         /* nfsd callbacks must have been installed for this procedure */
  31         if (!nlmsvc_ops)
  32                 return nlm_lck_denied_nolocks;
  33
  34         /* Obtain host handle */
  35         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  36          || (argp->monitor && nsm_monitor(host) < 0))
  37                 goto no_locks;
  38         *hostp = host;
  39
  40         /* Obtain file pointer. Not used by FREE_ALL call. */
  41         if (filp != NULL) {
  42                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  43                         goto no_locks;
  44                 *filp = file;
  45
  46                 /* Set up the missing parts of the file_lock structure */
  47                 lock->fl.fl_file  = file->f_file;
  48                 lock->fl.fl_owner = (fl_owner_t) host;
  49                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  50         }
  51
  52         return 0;
  53
  54 no_locks:
  55         nlmsvc_release_host(host);
  56         if (error)
  57                 return error;
  58         return nlm_lck_denied_nolocks;
  59 }
  60
  61 /*
  62  * NULL: Test for presence of service
  63  */
  64 static __be32
  65 nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  66 {
  67         dprintk("lockd: NULL          called\n");
  68         return rpc_success;
  69 }
  70
  71 /*
  72  * TEST: Check for conflicting lock
  73  */
  74 static __be32
  75 nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
  76                                          struct nlm_res  *resp)
  77 {
  78         struct nlm_host *host;
  79         struct nlm_file *file;
  80         __be32 rc = rpc_success;
  81
  82         dprintk("lockd: TEST4        called\n");
  83         resp->cookie = argp->cookie;
  84
  85         /* Obtain client and file */
  86         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  87                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  88
  89         /* Now check for conflicting locks */
  90         resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
  91         if (resp->status == nlm_drop_reply)
  92                 rc = rpc_drop_reply;
  93         else
  94                 dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
  95
  96         nlmsvc_release_host(host);
  97         nlm_release_file(file);
  98         return rc;
  99 }
 100
 101 static __be32
 102 nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 103                                          struct nlm_res  *resp)
 104 {
 105         struct nlm_host *host;
 106         struct nlm_file *file;
 107         __be32 rc = rpc_success;
 108
 109         dprintk("lockd: LOCK          called\n");
 110
 111         resp->cookie = argp->cookie;
 112
 113         /* Obtain client and file */
 114         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 115                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 116
 117 #if 0
 118         /* If supplied state doesn't match current state, we assume it's
 119          * an old request that time-warped somehow. Any error return would
 120          * do in this case because it's irrelevant anyway.
 121          *
 122          * NB: We don't retrieve the remote host's state yet.
 123          */
 124         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 125                 resp->status = nlm_lck_denied_nolocks;
 126         } else
 127 #endif
 128
 129         /* Now try to lock the file */
 130         resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
 131                                         argp->block, &argp->cookie,
 132                                         argp->reclaim);
 133         if (resp->status == nlm_drop_reply)
 134                 rc = rpc_drop_reply;
 135         else
 136                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 137
 138         nlmsvc_release_host(host);
 139         nlm_release_file(file);
 140         return rc;
 141 }
 142
 143 static __be32
 144 nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 145                                            struct nlm_res  *resp)
 146 {
 147         struct nlm_host *host;
 148         struct nlm_file *file;
 149
 150         dprintk("lockd: CANCEL        called\n");
 151
 152         resp->cookie = argp->cookie;
 153
 154         /* Don't accept requests during grace period */
 155         if (locks_in_grace(SVC_NET(rqstp))) {
 156                 resp->status = nlm_lck_denied_grace_period;
 157                 return rpc_success;
 158         }
 159
 160         /* Obtain client and file */
 161         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 162                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 163
 164         /* Try to cancel request. */
 165         resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
 166
 167         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 168         nlmsvc_release_host(host);
 169         nlm_release_file(file);
 170         return rpc_success;
 171 }
 172
 173 /*
 174  * UNLOCK: release a lock
 175  */
 176 static __be32
 177 nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 178                                            struct nlm_res  *resp)
 179 {
 180         struct nlm_host *host;
 181         struct nlm_file *file;
 182
 183         dprintk("lockd: UNLOCK        called\n");
 184
 185         resp->cookie = argp->cookie;
 186
 187         /* Don't accept new lock requests during grace period */
 188         if (locks_in_grace(SVC_NET(rqstp))) {
 189                 resp->status = nlm_lck_denied_grace_period;
 190                 return rpc_success;
 191         }
 192
 193         /* Obtain client and file */
 194         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 195                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 196
 197         /* Now try to remove the lock */
 198         resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
 199
 200         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 201         nlmsvc_release_host(host);
 202         nlm_release_file(file);
 203         return rpc_success;
 204 }
 205
 206 /*
 207  * GRANTED: A server calls us to tell that a process' lock request
 208  * was granted
 209  */
 210 static __be32
 211 nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 212                                             struct nlm_res  *resp)
 213 {
 214         resp->cookie = argp->cookie;
 215
 216         dprintk("lockd: GRANTED       called\n");
 217         resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
 218         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 219         return rpc_success;
 220 }
 221
 222 /*
 223  * This is the generic lockd callback for async RPC calls
 224  */
 225 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 226 {
 227         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 228                         -task->tk_status);
 229 }
 230
 231 static void nlm4svc_callback_release(void *data)
 232 {
 233         nlmsvc_release_call(data);
 234 }
 235
 236 static const struct rpc_call_ops nlm4svc_callback_ops = {
 237         .rpc_call_done = nlm4svc_callback_exit,
 238         .rpc_release = nlm4svc_callback_release,
 239 };
 240
 241 /*
 242  * `Async' versions of the above service routines. They aren't really,
 243  * because we send the callback before the reply proper. I hope this
 244  * doesn't break any clients.
 245  */
 246 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 247                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 248 {
 249         struct nlm_host *host;
 250         struct nlm_rqst *call;
 251         __be32 stat;
 252
 253         host = nlmsvc_lookup_host(rqstp,
 254                                   argp->lock.caller,
 255                                   argp->lock.len);
 256         if (host == NULL)
 257                 return rpc_system_err;
 258
 259         call = nlm_alloc_call(host);
 260         nlmsvc_release_host(host);
 261         if (call == NULL)
 262                 return rpc_system_err;
 263
 264         stat = func(rqstp, argp, &call->a_res);
 265         if (stat != 0) {
 266                 nlmsvc_release_call(call);
 267                 return stat;
 268         }
 269
 270         call->a_flags = RPC_TASK_ASYNC;
 271         if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
 272                 return rpc_system_err;
 273         return rpc_success;
 274 }
 275
 276 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 277                                              void            *resp)
 278 {
 279         dprintk("lockd: TEST_MSG      called\n");
 280         return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
 281 }
 282
 283 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 284                                              void            *resp)
 285 {
 286         dprintk("lockd: LOCK_MSG      called\n");
 287         return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
 288 }
 289
 290 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 291                                                void            *resp)
 292 {
 293         dprintk("lockd: CANCEL_MSG    called\n");
 294         return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
 295 }
 296
 297 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 298                                                void            *resp)
 299 {
 300         dprintk("lockd: UNLOCK_MSG    called\n");
 301         return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
 302 }
 303
 304 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 305                                                 void            *resp)
 306 {
 307         dprintk("lockd: GRANTED_MSG   called\n");
 308         return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
 309 }
 310
 311 /*
 312  * SHARE: create a DOS share or alter existing share.
 313  */
 314 static __be32
 315 nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 316                                           struct nlm_res  *resp)
 317 {
 318         struct nlm_host *host;
 319         struct nlm_file *file;
 320
 321         dprintk("lockd: SHARE         called\n");
 322
 323         resp->cookie = argp->cookie;
 324
 325         /* Don't accept new lock requests during grace period */
 326         if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
 327                 resp->status = nlm_lck_denied_grace_period;
 328                 return rpc_success;
 329         }
 330
 331         /* Obtain client and file */
 332         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 333                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 334
 335         /* Now try to create the share */
 336         resp->status = nlmsvc_share_file(host, file, argp);
 337
 338         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 339         nlmsvc_release_host(host);
 340         nlm_release_file(file);
 341         return rpc_success;
 342 }
 343
 344 /*
 345  * UNSHARE: Release a DOS share.
 346  */
 347 static __be32
 348 nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 349                                             struct nlm_res  *resp)
 350 {
 351         struct nlm_host *host;
 352         struct nlm_file *file;
 353
 354         dprintk("lockd: UNSHARE       called\n");
 355
 356         resp->cookie = argp->cookie;
 357
 358         /* Don't accept requests during grace period */
 359         if (locks_in_grace(SVC_NET(rqstp))) {
 360                 resp->status = nlm_lck_denied_grace_period;
 361                 return rpc_success;
 362         }
 363
 364         /* Obtain client and file */
 365         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 366                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 367
 368         /* Now try to lock the file */
 369         resp->status = nlmsvc_unshare_file(host, file, argp);
 370
 371         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 372         nlmsvc_release_host(host);
 373         nlm_release_file(file);
 374         return rpc_success;
 375 }
 376
 377 /*
 378  * NM_LOCK: Create an unmonitored lock
 379  */
 380 static __be32
 381 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 382                                             struct nlm_res  *resp)
 383 {
 384         dprintk("lockd: NM_LOCK       called\n");
 385
 386         argp->monitor = 0;              /* just clean the monitor flag */
 387         return nlm4svc_proc_lock(rqstp, argp, resp);
 388 }
 389
 390 /*
 391  * FREE_ALL: Release all locks and shares held by client
 392  */
 393 static __be32
 394 nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 395                                              void            *resp)
 396 {
 397         struct nlm_host *host;
 398
 399         /* Obtain client */
 400         if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
 401                 return rpc_success;
 402
 403         nlmsvc_free_host_resources(host);
 404         nlmsvc_release_host(host);
 405         return rpc_success;
 406 }
 407
 408 /*
 409  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 410  */
 411 static __be32
 412 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 413                                               void              *resp)
 414 {
 415         dprintk("lockd: SM_NOTIFY     called\n");
 416
 417         if (!nlm_privileged_requester(rqstp)) {
 418                 char buf[RPC_MAX_ADDRBUFLEN];
 419                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 420                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 421                 return rpc_system_err;
 422         }
 423
 424         nlm_host_rebooted(argp);
 425         return rpc_success;
 426 }
 427
 428 /*
 429  * client sent a GRANTED_RES, let's remove the associated block
 430  */
 431 static __be32
 432 nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 433                                                 void            *resp)
 434 {
 435         if (!nlmsvc_ops)
 436                 return rpc_success;
 437
 438         dprintk("lockd: GRANTED_RES   called\n");
 439
 440         nlmsvc_grant_reply(&argp->cookie, argp->status);
 441         return rpc_success;
 442 }
 443
 444
 445 /*
 446  * NLM Server procedures.
 447  */
 448
 449 #define nlm4svc_encode_norep    nlm4svc_encode_void
 450 #define nlm4svc_decode_norep    nlm4svc_decode_void
 451 #define nlm4svc_decode_testres  nlm4svc_decode_void
 452 #define nlm4svc_decode_lockres  nlm4svc_decode_void
 453 #define nlm4svc_decode_unlockres        nlm4svc_decode_void
 454 #define nlm4svc_decode_cancelres        nlm4svc_decode_void
 455 #define nlm4svc_decode_grantedres       nlm4svc_decode_void
 456
 457 #define nlm4svc_proc_none       nlm4svc_proc_null
 458 #define nlm4svc_proc_test_res   nlm4svc_proc_null
 459 #define nlm4svc_proc_lock_res   nlm4svc_proc_null
 460 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
 461 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
 462
 463 struct nlm_void                 { int dummy; };
 464
 465 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 466  { .pc_func     = (svc_procfunc) nlm4svc_proc_##name,   \
 467    .pc_decode   = (kxdrproc_t) nlm4svc_decode_##xargt,  \
 468    .pc_encode   = (kxdrproc_t) nlm4svc_encode_##xrest,  \
 469    .pc_release  = NULL,                                 \
 470    .pc_argsize  = sizeof(struct nlm_##argt),            \
 471    .pc_ressize  = sizeof(struct nlm_##rest),            \
 472    .pc_xdrressize = respsize,                           \
 473  }
 474 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 475 #define No      (1+1024/4)                              /* netobj */
 476 #define St      1                                       /* status */
 477 #define Rg      4                                       /* range (offset + length) */
 478 struct svc_procedure            nlmsvc_procedures4[] = {
 479   PROC(null,            void,           void,           void,   void, 1),
 480   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 481   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 482   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 483   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 484   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 485   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 486   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 487   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 488   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 489   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 490   PROC(test_res,        testres,        norep,          res,    void, 1),
 491   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 492   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 493   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 494   PROC(granted_res,     res,            norep,          res,    void, 1),
 495   /* statd callback */
 496   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 497   PROC(none,            void,           void,           void,   void, 0),
 498   PROC(none,            void,           void,           void,   void, 0),
 499   PROC(none,            void,           void,           void,   void, 0),
 500   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 501   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 502   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 503   PROC(free_all,        notify,         void,           args,   void, 1),
 504
 505 };