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                 case nlm_drop_reply:
  37                         break;
  38                 case nlm4_deadlock:
  39                         status = nlm_lck_denied;
  40                         break;
  41                 default:
  42                         status = nlm_lck_denied_nolocks;
  43                 }
  44         }
  45
  46         return (status);
  47 }
  48 #define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
  49 #else
  50 #define cast_status(status) (status)
  51 #endif
  52
  53 /*
  54  * Obtain client and file from arguments
  55  */
  56 static __be32
  57 nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  58                         struct nlm_host **hostp, struct nlm_file **filp)
  59 {
  60         struct nlm_host         *host = NULL;
  61         struct nlm_file         *file = NULL;
  62         struct nlm_lock         *lock = &argp->lock;
  63         __be32                  error = 0;
  64
  65         /* nfsd callbacks must have been installed for this procedure */
  66         if (!nlmsvc_ops)
  67                 return nlm_lck_denied_nolocks;
  68
  69         /* Obtain host handle */
  70         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  71          || (argp->monitor && nsm_monitor(host) < 0))
  72                 goto no_locks;
  73         *hostp = host;
  74
  75         /* Obtain file pointer. Not used by FREE_ALL call. */
  76         if (filp != NULL) {
  77                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  78                         goto no_locks;
  79                 *filp = file;
  80
  81                 /* Set up the missing parts of the file_lock structure */
  82                 lock->fl.fl_file  = file->f_file;
  83                 lock->fl.fl_owner = (fl_owner_t) host;
  84                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  85         }
  86
  87         return 0;
  88
  89 no_locks:
  90         if (host)
  91                 nlm_release_host(host);
  92         if (error)
  93                 return error;
  94         return nlm_lck_denied_nolocks;
  95 }
  96
  97 /*
  98  * NULL: Test for presence of service
  99  */
 100 static __be32
 101 nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
 102 {
 103         dprintk("lockd: NULL          called\n");
 104         return rpc_success;
 105 }
 106
 107 /*
 108  * TEST: Check for conflicting lock
 109  */
 110 static __be32
 111 nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
 112                                          struct nlm_res  *resp)
 113 {
 114         struct nlm_host *host;
 115         struct nlm_file *file;
 116
 117         dprintk("lockd: TEST          called\n");
 118         resp->cookie = argp->cookie;
 119
 120         /* Don't accept test requests during grace period */
 121         if (nlmsvc_grace_period) {
 122                 resp->status = nlm_lck_denied_grace_period;
 123                 return rpc_success;
 124         }
 125
 126         /* Obtain client and file */
 127         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 128                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 129
 130         /* Now check for conflicting locks */
 131         resp->status = cast_status(nlmsvc_testlock(rqstp, file, &argp->lock, &resp->lock, &resp->cookie));
 132         if (resp->status == nlm_drop_reply)
 133                 return rpc_drop_reply;
 134
 135         dprintk("lockd: TEST          status %d vers %d\n",
 136                 ntohl(resp->status), rqstp->rq_vers);
 137         nlm_release_host(host);
 138         nlm_release_file(file);
 139         return rpc_success;
 140 }
 141
 142 static __be32
 143 nlmsvc_proc_lock(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: LOCK          called\n");
 150
 151         resp->cookie = argp->cookie;
 152
 153         /* Don't accept new lock requests during grace period */
 154         if (nlmsvc_grace_period && !argp->reclaim) {
 155                 resp->status = nlm_lck_denied_grace_period;
 156                 return rpc_success;
 157         }
 158
 159         /* Obtain client and file */
 160         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 161                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 162
 163 #if 0
 164         /* If supplied state doesn't match current state, we assume it's
 165          * an old request that time-warped somehow. Any error return would
 166          * do in this case because it's irrelevant anyway.
 167          *
 168          * NB: We don't retrieve the remote host's state yet.
 169          */
 170         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 171                 resp->status = nlm_lck_denied_nolocks;
 172         } else
 173 #endif
 174
 175         /* Now try to lock the file */
 176         resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
 177                                                argp->block, &argp->cookie));
 178         if (resp->status == nlm_drop_reply)
 179                 return rpc_drop_reply;
 180
 181         dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
 182         nlm_release_host(host);
 183         nlm_release_file(file);
 184         return rpc_success;
 185 }
 186
 187 static __be32
 188 nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 189                                            struct nlm_res  *resp)
 190 {
 191         struct nlm_host *host;
 192         struct nlm_file *file;
 193
 194         dprintk("lockd: CANCEL        called\n");
 195
 196         resp->cookie = argp->cookie;
 197
 198         /* Don't accept requests during grace period */
 199         if (nlmsvc_grace_period) {
 200                 resp->status = nlm_lck_denied_grace_period;
 201                 return rpc_success;
 202         }
 203
 204         /* Obtain client and file */
 205         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 206                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 207
 208         /* Try to cancel request. */
 209         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 210
 211         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 212         nlm_release_host(host);
 213         nlm_release_file(file);
 214         return rpc_success;
 215 }
 216
 217 /*
 218  * UNLOCK: release a lock
 219  */
 220 static __be32
 221 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 222                                            struct nlm_res  *resp)
 223 {
 224         struct nlm_host *host;
 225         struct nlm_file *file;
 226
 227         dprintk("lockd: UNLOCK        called\n");
 228
 229         resp->cookie = argp->cookie;
 230
 231         /* Don't accept new lock requests during grace period */
 232         if (nlmsvc_grace_period) {
 233                 resp->status = nlm_lck_denied_grace_period;
 234                 return rpc_success;
 235         }
 236
 237         /* Obtain client and file */
 238         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 239                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 240
 241         /* Now try to remove the lock */
 242         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 243
 244         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 245         nlm_release_host(host);
 246         nlm_release_file(file);
 247         return rpc_success;
 248 }
 249
 250 /*
 251  * GRANTED: A server calls us to tell that a process' lock request
 252  * was granted
 253  */
 254 static __be32
 255 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 256                                             struct nlm_res  *resp)
 257 {
 258         resp->cookie = argp->cookie;
 259
 260         dprintk("lockd: GRANTED       called\n");
 261         resp->status = nlmclnt_grant(svc_addr_in(rqstp), &argp->lock);
 262         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 263         return rpc_success;
 264 }
 265
 266 /*
 267  * This is the generic lockd callback for async RPC calls
 268  */
 269 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 270 {
 271         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 272                         -task->tk_status);
 273 }
 274
 275 static void nlmsvc_callback_release(void *data)
 276 {
 277         nlm_release_call(data);
 278 }
 279
 280 static const struct rpc_call_ops nlmsvc_callback_ops = {
 281         .rpc_call_done = nlmsvc_callback_exit,
 282         .rpc_release = nlmsvc_callback_release,
 283 };
 284
 285 /*
 286  * `Async' versions of the above service routines. They aren't really,
 287  * because we send the callback before the reply proper. I hope this
 288  * doesn't break any clients.
 289  */
 290 static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 291                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 292 {
 293         struct nlm_host *host;
 294         struct nlm_rqst *call;
 295         __be32 stat;
 296
 297         host = nlmsvc_lookup_host(rqstp,
 298                                   argp->lock.caller,
 299                                   argp->lock.len);
 300         if (host == NULL)
 301                 return rpc_system_err;
 302
 303         call = nlm_alloc_call(host);
 304         if (call == NULL)
 305                 return rpc_system_err;
 306
 307         stat = func(rqstp, argp, &call->a_res);
 308         if (stat != 0) {
 309                 nlm_release_call(call);
 310                 return stat;
 311         }
 312
 313         call->a_flags = RPC_TASK_ASYNC;
 314         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 315                 return rpc_system_err;
 316         return rpc_success;
 317 }
 318
 319 static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 320                                              void            *resp)
 321 {
 322         dprintk("lockd: TEST_MSG      called\n");
 323         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 324 }
 325
 326 static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 327                                              void            *resp)
 328 {
 329         dprintk("lockd: LOCK_MSG      called\n");
 330         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 331 }
 332
 333 static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 334                                                void            *resp)
 335 {
 336         dprintk("lockd: CANCEL_MSG    called\n");
 337         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 338 }
 339
 340 static __be32
 341 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 342                                                void            *resp)
 343 {
 344         dprintk("lockd: UNLOCK_MSG    called\n");
 345         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 346 }
 347
 348 static __be32
 349 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 350                                                 void            *resp)
 351 {
 352         dprintk("lockd: GRANTED_MSG   called\n");
 353         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 354 }
 355
 356 /*
 357  * SHARE: create a DOS share or alter existing share.
 358  */
 359 static __be32
 360 nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 361                                           struct nlm_res  *resp)
 362 {
 363         struct nlm_host *host;
 364         struct nlm_file *file;
 365
 366         dprintk("lockd: SHARE         called\n");
 367
 368         resp->cookie = argp->cookie;
 369
 370         /* Don't accept new lock requests during grace period */
 371         if (nlmsvc_grace_period && !argp->reclaim) {
 372                 resp->status = nlm_lck_denied_grace_period;
 373                 return rpc_success;
 374         }
 375
 376         /* Obtain client and file */
 377         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 378                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 379
 380         /* Now try to create the share */
 381         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 382
 383         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 384         nlm_release_host(host);
 385         nlm_release_file(file);
 386         return rpc_success;
 387 }
 388
 389 /*
 390  * UNSHARE: Release a DOS share.
 391  */
 392 static __be32
 393 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 394                                             struct nlm_res  *resp)
 395 {
 396         struct nlm_host *host;
 397         struct nlm_file *file;
 398
 399         dprintk("lockd: UNSHARE       called\n");
 400
 401         resp->cookie = argp->cookie;
 402
 403         /* Don't accept requests during grace period */
 404         if (nlmsvc_grace_period) {
 405                 resp->status = nlm_lck_denied_grace_period;
 406                 return rpc_success;
 407         }
 408
 409         /* Obtain client and file */
 410         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 411                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 412
 413         /* Now try to unshare the file */
 414         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 415
 416         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 417         nlm_release_host(host);
 418         nlm_release_file(file);
 419         return rpc_success;
 420 }
 421
 422 /*
 423  * NM_LOCK: Create an unmonitored lock
 424  */
 425 static __be32
 426 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 427                                             struct nlm_res  *resp)
 428 {
 429         dprintk("lockd: NM_LOCK       called\n");
 430
 431         argp->monitor = 0;              /* just clean the monitor flag */
 432         return nlmsvc_proc_lock(rqstp, argp, resp);
 433 }
 434
 435 /*
 436  * FREE_ALL: Release all locks and shares held by client
 437  */
 438 static __be32
 439 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 440                                              void            *resp)
 441 {
 442         struct nlm_host *host;
 443
 444         /* Obtain client */
 445         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 446                 return rpc_success;
 447
 448         nlmsvc_free_host_resources(host);
 449         nlm_release_host(host);
 450         return rpc_success;
 451 }
 452
 453 /*
 454  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 455  */
 456 static __be32
 457 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 458                                               void              *resp)
 459 {
 460         struct sockaddr_in      saddr;
 461
 462         memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
 463
 464         dprintk("lockd: SM_NOTIFY     called\n");
 465         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 466          || ntohs(saddr.sin_port) >= 1024) {
 467                 char buf[RPC_MAX_ADDRBUFLEN];
 468                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 469                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 470                 return rpc_system_err;
 471         }
 472
 473         /* Obtain the host pointer for this NFS server and try to
 474          * reclaim all locks we hold on this server.
 475          */
 476         memset(&saddr, 0, sizeof(saddr));
 477         saddr.sin_addr.s_addr = argp->addr;
 478         nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
 479
 480         return rpc_success;
 481 }
 482
 483 /*
 484  * client sent a GRANTED_RES, let's remove the associated block
 485  */
 486 static __be32
 487 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 488                                                 void            *resp)
 489 {
 490         if (!nlmsvc_ops)
 491                 return rpc_success;
 492
 493         dprintk("lockd: GRANTED_RES   called\n");
 494
 495         nlmsvc_grant_reply(&argp->cookie, argp->status);
 496         return rpc_success;
 497 }
 498
 499 /*
 500  * NLM Server procedures.
 501  */
 502
 503 #define nlmsvc_encode_norep     nlmsvc_encode_void
 504 #define nlmsvc_decode_norep     nlmsvc_decode_void
 505 #define nlmsvc_decode_testres   nlmsvc_decode_void
 506 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 507 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 508 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 509 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 510
 511 #define nlmsvc_proc_none        nlmsvc_proc_null
 512 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 513 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 514 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 515 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 516
 517 struct nlm_void                 { int dummy; };
 518
 519 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 520  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 521    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 522    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 523    .pc_release  = NULL,                                 \
 524    .pc_argsize  = sizeof(struct nlm_##argt),            \
 525    .pc_ressize  = sizeof(struct nlm_##rest),            \
 526    .pc_xdrressize = respsize,                           \
 527  }
 528
 529 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 530 #define St      1                               /* status */
 531 #define No      (1+1024/4)                      /* Net Obj */
 532 #define Rg      2                               /* range - offset + size */
 533
 534 struct svc_procedure            nlmsvc_procedures[] = {
 535   PROC(null,            void,           void,           void,   void, 1),
 536   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 537   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 538   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 539   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 540   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 541   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 542   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 543   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 544   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 545   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 546   PROC(test_res,        testres,        norep,          res,    void, 1),
 547   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 548   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 549   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 550   PROC(granted_res,     res,            norep,          res,    void, 1),
 551   /* statd callback */
 552   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 553   PROC(none,            void,           void,           void,   void, 1),
 554   PROC(none,            void,           void,           void,   void, 1),
 555   PROC(none,            void,           void,           void,   void, 1),
 556   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 557   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 558   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 559   PROC(free_all,        notify,         void,           args,   void, 0),
 560
 561 };