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/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
  20 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  21
  22 /*
  23  * Obtain client and file from arguments
  24  */
  25 static __be32
  26 nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  27                         struct nlm_host **hostp, struct nlm_file **filp)
  28 {
  29         struct nlm_host         *host = NULL;
  30         struct nlm_file         *file = NULL;
  31         struct nlm_lock         *lock = &argp->lock;
  32         __be32                  error = 0;
  33
  34         /* nfsd callbacks must have been installed for this procedure */
  35         if (!nlmsvc_ops)
  36                 return nlm_lck_denied_nolocks;
  37
  38         /* Obtain host handle */
  39         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  40          || (argp->monitor && nsm_monitor(host) < 0))
  41                 goto no_locks;
  42         *hostp = host;
  43
  44         /* Obtain file pointer. Not used by FREE_ALL call. */
  45         if (filp != NULL) {
  46                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  47                         goto no_locks;
  48                 *filp = file;
  49
  50                 /* Set up the missing parts of the file_lock structure */
  51                 lock->fl.fl_file  = file->f_file;
  52                 lock->fl.fl_owner = (fl_owner_t) host;
  53                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  54         }
  55
  56         return 0;
  57
  58 no_locks:
  59         nlm_release_host(host);
  60         if (error)
  61                 return error;
  62         return nlm_lck_denied_nolocks;
  63 }
  64
  65 /*
  66  * NULL: Test for presence of service
  67  */
  68 static __be32
  69 nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  70 {
  71         dprintk("lockd: NULL          called\n");
  72         return rpc_success;
  73 }
  74
  75 /*
  76  * TEST: Check for conflicting lock
  77  */
  78 static __be32
  79 nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
  80                                          struct nlm_res  *resp)
  81 {
  82         struct nlm_host *host;
  83         struct nlm_file *file;
  84         __be32 rc = rpc_success;
  85
  86         dprintk("lockd: TEST4        called\n");
  87         resp->cookie = argp->cookie;
  88
  89         /* Obtain client and file */
  90         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  91                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  92
  93         /* Now check for conflicting locks */
  94         resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
  95         if (resp->status == nlm_drop_reply)
  96                 rc = rpc_drop_reply;
  97         else
  98                 dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
  99
 100         nlm_release_host(host);
 101         nlm_release_file(file);
 102         return rc;
 103 }
 104
 105 static __be32
 106 nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 107                                          struct nlm_res  *resp)
 108 {
 109         struct nlm_host *host;
 110         struct nlm_file *file;
 111         __be32 rc = rpc_success;
 112
 113         dprintk("lockd: LOCK          called\n");
 114
 115         resp->cookie = argp->cookie;
 116
 117         /* Obtain client and file */
 118         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 119                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 120
 121 #if 0
 122         /* If supplied state doesn't match current state, we assume it's
 123          * an old request that time-warped somehow. Any error return would
 124          * do in this case because it's irrelevant anyway.
 125          *
 126          * NB: We don't retrieve the remote host's state yet.
 127          */
 128         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 129                 resp->status = nlm_lck_denied_nolocks;
 130         } else
 131 #endif
 132
 133         /* Now try to lock the file */
 134         resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
 135                                         argp->block, &argp->cookie,
 136                                         argp->reclaim);
 137         if (resp->status == nlm_drop_reply)
 138                 rc = rpc_drop_reply;
 139         else
 140                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 141
 142         nlm_release_host(host);
 143         nlm_release_file(file);
 144         return rc;
 145 }
 146
 147 static __be32
 148 nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 149                                            struct nlm_res  *resp)
 150 {
 151         struct nlm_host *host;
 152         struct nlm_file *file;
 153
 154         dprintk("lockd: CANCEL        called\n");
 155
 156         resp->cookie = argp->cookie;
 157
 158         /* Don't accept requests during grace period */
 159         if (locks_in_grace()) {
 160                 resp->status = nlm_lck_denied_grace_period;
 161                 return rpc_success;
 162         }
 163
 164         /* Obtain client and file */
 165         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 166                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 167
 168         /* Try to cancel request. */
 169         resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
 170
 171         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 172         nlm_release_host(host);
 173         nlm_release_file(file);
 174         return rpc_success;
 175 }
 176
 177 /*
 178  * UNLOCK: release a lock
 179  */
 180 static __be32
 181 nlm4svc_proc_unlock(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: UNLOCK        called\n");
 188
 189         resp->cookie = argp->cookie;
 190
 191         /* Don't accept new lock requests during grace period */
 192         if (locks_in_grace()) {
 193                 resp->status = nlm_lck_denied_grace_period;
 194                 return rpc_success;
 195         }
 196
 197         /* Obtain client and file */
 198         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 199                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 200
 201         /* Now try to remove the lock */
 202         resp->status = nlmsvc_unlock(file, &argp->lock);
 203
 204         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 205         nlm_release_host(host);
 206         nlm_release_file(file);
 207         return rpc_success;
 208 }
 209
 210 /*
 211  * GRANTED: A server calls us to tell that a process' lock request
 212  * was granted
 213  */
 214 static __be32
 215 nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 216                                             struct nlm_res  *resp)
 217 {
 218         resp->cookie = argp->cookie;
 219
 220         dprintk("lockd: GRANTED       called\n");
 221         resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
 222         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 223         return rpc_success;
 224 }
 225
 226 /*
 227  * This is the generic lockd callback for async RPC calls
 228  */
 229 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 230 {
 231         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 232                         -task->tk_status);
 233 }
 234
 235 static void nlm4svc_callback_release(void *data)
 236 {
 237         lock_kernel();
 238         nlm_release_call(data);
 239         unlock_kernel();
 240 }
 241
 242 static const struct rpc_call_ops nlm4svc_callback_ops = {
 243         .rpc_call_done = nlm4svc_callback_exit,
 244         .rpc_release = nlm4svc_callback_release,
 245 };
 246
 247 /*
 248  * `Async' versions of the above service routines. They aren't really,
 249  * because we send the callback before the reply proper. I hope this
 250  * doesn't break any clients.
 251  */
 252 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 253                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 254 {
 255         struct nlm_host *host;
 256         struct nlm_rqst *call;
 257         __be32 stat;
 258
 259         host = nlmsvc_lookup_host(rqstp,
 260                                   argp->lock.caller,
 261                                   argp->lock.len);
 262         if (host == NULL)
 263                 return rpc_system_err;
 264
 265         call = nlm_alloc_call(host);
 266         if (call == NULL)
 267                 return rpc_system_err;
 268
 269         stat = func(rqstp, argp, &call->a_res);
 270         if (stat != 0) {
 271                 nlm_release_call(call);
 272                 return stat;
 273         }
 274
 275         call->a_flags = RPC_TASK_ASYNC;
 276         if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
 277                 return rpc_system_err;
 278         return rpc_success;
 279 }
 280
 281 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 282                                              void            *resp)
 283 {
 284         dprintk("lockd: TEST_MSG      called\n");
 285         return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
 286 }
 287
 288 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 289                                              void            *resp)
 290 {
 291         dprintk("lockd: LOCK_MSG      called\n");
 292         return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
 293 }
 294
 295 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 296                                                void            *resp)
 297 {
 298         dprintk("lockd: CANCEL_MSG    called\n");
 299         return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
 300 }
 301
 302 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 303                                                void            *resp)
 304 {
 305         dprintk("lockd: UNLOCK_MSG    called\n");
 306         return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
 307 }
 308
 309 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 310                                                 void            *resp)
 311 {
 312         dprintk("lockd: GRANTED_MSG   called\n");
 313         return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
 314 }
 315
 316 /*
 317  * SHARE: create a DOS share or alter existing share.
 318  */
 319 static __be32
 320 nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 321                                           struct nlm_res  *resp)
 322 {
 323         struct nlm_host *host;
 324         struct nlm_file *file;
 325
 326         dprintk("lockd: SHARE         called\n");
 327
 328         resp->cookie = argp->cookie;
 329
 330         /* Don't accept new lock requests during grace period */
 331         if (locks_in_grace() && !argp->reclaim) {
 332                 resp->status = nlm_lck_denied_grace_period;
 333                 return rpc_success;
 334         }
 335
 336         /* Obtain client and file */
 337         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 338                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 339
 340         /* Now try to create the share */
 341         resp->status = nlmsvc_share_file(host, file, argp);
 342
 343         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 344         nlm_release_host(host);
 345         nlm_release_file(file);
 346         return rpc_success;
 347 }
 348
 349 /*
 350  * UNSHARE: Release a DOS share.
 351  */
 352 static __be32
 353 nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 354                                             struct nlm_res  *resp)
 355 {
 356         struct nlm_host *host;
 357         struct nlm_file *file;
 358
 359         dprintk("lockd: UNSHARE       called\n");
 360
 361         resp->cookie = argp->cookie;
 362
 363         /* Don't accept requests during grace period */
 364         if (locks_in_grace()) {
 365                 resp->status = nlm_lck_denied_grace_period;
 366                 return rpc_success;
 367         }
 368
 369         /* Obtain client and file */
 370         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 371                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 372
 373         /* Now try to lock the file */
 374         resp->status = nlmsvc_unshare_file(host, file, argp);
 375
 376         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 377         nlm_release_host(host);
 378         nlm_release_file(file);
 379         return rpc_success;
 380 }
 381
 382 /*
 383  * NM_LOCK: Create an unmonitored lock
 384  */
 385 static __be32
 386 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 387                                             struct nlm_res  *resp)
 388 {
 389         dprintk("lockd: NM_LOCK       called\n");
 390
 391         argp->monitor = 0;              /* just clean the monitor flag */
 392         return nlm4svc_proc_lock(rqstp, argp, resp);
 393 }
 394
 395 /*
 396  * FREE_ALL: Release all locks and shares held by client
 397  */
 398 static __be32
 399 nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 400                                              void            *resp)
 401 {
 402         struct nlm_host *host;
 403
 404         /* Obtain client */
 405         if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
 406                 return rpc_success;
 407
 408         nlmsvc_free_host_resources(host);
 409         nlm_release_host(host);
 410         return rpc_success;
 411 }
 412
 413 /*
 414  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 415  */
 416 static __be32
 417 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 418                                               void              *resp)
 419 {
 420         dprintk("lockd: SM_NOTIFY     called\n");
 421
 422         if (!nlm_privileged_requester(rqstp)) {
 423                 char buf[RPC_MAX_ADDRBUFLEN];
 424                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 425                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 426                 return rpc_system_err;
 427         }
 428
 429         nlm_host_rebooted(argp);
 430         return rpc_success;
 431 }
 432
 433 /*
 434  * client sent a GRANTED_RES, let's remove the associated block
 435  */
 436 static __be32
 437 nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 438                                                 void            *resp)
 439 {
 440         if (!nlmsvc_ops)
 441                 return rpc_success;
 442
 443         dprintk("lockd: GRANTED_RES   called\n");
 444
 445         nlmsvc_grant_reply(&argp->cookie, argp->status);
 446         return rpc_success;
 447 }
 448
 449
 450 /*
 451  * NLM Server procedures.
 452  */
 453
 454 #define nlm4svc_encode_norep    nlm4svc_encode_void
 455 #define nlm4svc_decode_norep    nlm4svc_decode_void
 456 #define nlm4svc_decode_testres  nlm4svc_decode_void
 457 #define nlm4svc_decode_lockres  nlm4svc_decode_void
 458 #define nlm4svc_decode_unlockres        nlm4svc_decode_void
 459 #define nlm4svc_decode_cancelres        nlm4svc_decode_void
 460 #define nlm4svc_decode_grantedres       nlm4svc_decode_void
 461
 462 #define nlm4svc_proc_none       nlm4svc_proc_null
 463 #define nlm4svc_proc_test_res   nlm4svc_proc_null
 464 #define nlm4svc_proc_lock_res   nlm4svc_proc_null
 465 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
 466 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
 467
 468 struct nlm_void                 { int dummy; };
 469
 470 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 471  { .pc_func     = (svc_procfunc) nlm4svc_proc_##name,   \
 472    .pc_decode   = (kxdrproc_t) nlm4svc_decode_##xargt,  \
 473    .pc_encode   = (kxdrproc_t) nlm4svc_encode_##xrest,  \
 474    .pc_release  = NULL,                                 \
 475    .pc_argsize  = sizeof(struct nlm_##argt),            \
 476    .pc_ressize  = sizeof(struct nlm_##rest),            \
 477    .pc_xdrressize = respsize,                           \
 478  }
 479 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 480 #define No      (1+1024/4)                              /* netobj */
 481 #define St      1                                       /* status */
 482 #define Rg      4                                       /* range (offset + length) */
 483 struct svc_procedure            nlmsvc_procedures4[] = {
 484   PROC(null,            void,           void,           void,   void, 1),
 485   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 486   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 487   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 488   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 489   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 490   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 491   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 492   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 493   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 494   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 495   PROC(test_res,        testres,        norep,          res,    void, 1),
 496   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 497   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 498   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 499   PROC(granted_res,     res,            norep,          res,    void, 1),
 500   /* statd callback */
 501   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 502   PROC(none,            void,           void,           void,   void, 0),
 503   PROC(none,            void,           void,           void,   void, 0),
 504   PROC(none,            void,           void,           void,   void, 0),
 505   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 506   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 507   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 508   PROC(free_all,        notify,         void,           args,   void, 1),
 509
 510 };