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 #include <linux/lockd/sm_inter.h>
  20
  21
  22 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  23
  24 /*
  25  * Obtain client and file from arguments
  26  */
  27 static __be32
  28 nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  29                         struct nlm_host **hostp, struct nlm_file **filp)
  30 {
  31         struct nlm_host         *host = NULL;
  32         struct nlm_file         *file = NULL;
  33         struct nlm_lock         *lock = &argp->lock;
  34         __be32                  error = 0;
  35
  36         /* nfsd callbacks must have been installed for this procedure */
  37         if (!nlmsvc_ops)
  38                 return nlm_lck_denied_nolocks;
  39
  40         /* Obtain host handle */
  41         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  42          || (argp->monitor && nsm_monitor(host) < 0))
  43                 goto no_locks;
  44         *hostp = host;
  45
  46         /* Obtain file pointer. Not used by FREE_ALL call. */
  47         if (filp != NULL) {
  48                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  49                         goto no_locks;
  50                 *filp = file;
  51
  52                 /* Set up the missing parts of the file_lock structure */
  53                 lock->fl.fl_file  = file->f_file;
  54                 lock->fl.fl_owner = (fl_owner_t) host;
  55                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  56         }
  57
  58         return 0;
  59
  60 no_locks:
  61         nlm_release_host(host);
  62         if (error)
  63                 return error;
  64         return nlm_lck_denied_nolocks;
  65 }
  66
  67 /*
  68  * NULL: Test for presence of service
  69  */
  70 static __be32
  71 nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  72 {
  73         dprintk("lockd: NULL          called\n");
  74         return rpc_success;
  75 }
  76
  77 /*
  78  * TEST: Check for conflicting lock
  79  */
  80 static __be32
  81 nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
  82                                          struct nlm_res  *resp)
  83 {
  84         struct nlm_host *host;
  85         struct nlm_file *file;
  86         int rc = rpc_success;
  87
  88         dprintk("lockd: TEST4        called\n");
  89         resp->cookie = argp->cookie;
  90
  91         /* Don't accept test requests during grace period */
  92         if (nlmsvc_grace_period) {
  93                 resp->status = nlm_lck_denied_grace_period;
  94                 return rc;
  95         }
  96
  97         /* Obtain client and file */
  98         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  99                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 100
 101         /* Now check for conflicting locks */
 102         resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
 103         if (resp->status == nlm_drop_reply)
 104                 rc = rpc_drop_reply;
 105         else
 106                 dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
 107
 108         nlm_release_host(host);
 109         nlm_release_file(file);
 110         return rc;
 111 }
 112
 113 static __be32
 114 nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 115                                          struct nlm_res  *resp)
 116 {
 117         struct nlm_host *host;
 118         struct nlm_file *file;
 119         int rc = rpc_success;
 120
 121         dprintk("lockd: LOCK          called\n");
 122
 123         resp->cookie = argp->cookie;
 124
 125         /* Don't accept new lock requests during grace period */
 126         if (nlmsvc_grace_period && !argp->reclaim) {
 127                 resp->status = nlm_lck_denied_grace_period;
 128                 return rc;
 129         }
 130
 131         /* Obtain client and file */
 132         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 133                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 134
 135 #if 0
 136         /* If supplied state doesn't match current state, we assume it's
 137          * an old request that time-warped somehow. Any error return would
 138          * do in this case because it's irrelevant anyway.
 139          *
 140          * NB: We don't retrieve the remote host's state yet.
 141          */
 142         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 143                 resp->status = nlm_lck_denied_nolocks;
 144         } else
 145 #endif
 146
 147         /* Now try to lock the file */
 148         resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
 149                                         argp->block, &argp->cookie);
 150         if (resp->status == nlm_drop_reply)
 151                 rc = rpc_drop_reply;
 152         else
 153                 dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
 154
 155         nlm_release_host(host);
 156         nlm_release_file(file);
 157         return rc;
 158 }
 159
 160 static __be32
 161 nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 162                                            struct nlm_res  *resp)
 163 {
 164         struct nlm_host *host;
 165         struct nlm_file *file;
 166
 167         dprintk("lockd: CANCEL        called\n");
 168
 169         resp->cookie = argp->cookie;
 170
 171         /* Don't accept requests during grace period */
 172         if (nlmsvc_grace_period) {
 173                 resp->status = nlm_lck_denied_grace_period;
 174                 return rpc_success;
 175         }
 176
 177         /* Obtain client and file */
 178         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 179                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 180
 181         /* Try to cancel request. */
 182         resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
 183
 184         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 185         nlm_release_host(host);
 186         nlm_release_file(file);
 187         return rpc_success;
 188 }
 189
 190 /*
 191  * UNLOCK: release a lock
 192  */
 193 static __be32
 194 nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 195                                            struct nlm_res  *resp)
 196 {
 197         struct nlm_host *host;
 198         struct nlm_file *file;
 199
 200         dprintk("lockd: UNLOCK        called\n");
 201
 202         resp->cookie = argp->cookie;
 203
 204         /* Don't accept new lock requests during grace period */
 205         if (nlmsvc_grace_period) {
 206                 resp->status = nlm_lck_denied_grace_period;
 207                 return rpc_success;
 208         }
 209
 210         /* Obtain client and file */
 211         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 212                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 213
 214         /* Now try to remove the lock */
 215         resp->status = nlmsvc_unlock(file, &argp->lock);
 216
 217         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 218         nlm_release_host(host);
 219         nlm_release_file(file);
 220         return rpc_success;
 221 }
 222
 223 /*
 224  * GRANTED: A server calls us to tell that a process' lock request
 225  * was granted
 226  */
 227 static __be32
 228 nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 229                                             struct nlm_res  *resp)
 230 {
 231         resp->cookie = argp->cookie;
 232
 233         dprintk("lockd: GRANTED       called\n");
 234         resp->status = nlmclnt_grant(svc_addr_in(rqstp), &argp->lock);
 235         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 236         return rpc_success;
 237 }
 238
 239 /*
 240  * This is the generic lockd callback for async RPC calls
 241  */
 242 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
 243 {
 244         dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
 245                         -task->tk_status);
 246 }
 247
 248 static void nlm4svc_callback_release(void *data)
 249 {
 250         lock_kernel();
 251         nlm_release_call(data);
 252         unlock_kernel();
 253 }
 254
 255 static const struct rpc_call_ops nlm4svc_callback_ops = {
 256         .rpc_call_done = nlm4svc_callback_exit,
 257         .rpc_release = nlm4svc_callback_release,
 258 };
 259
 260 /*
 261  * `Async' versions of the above service routines. They aren't really,
 262  * because we send the callback before the reply proper. I hope this
 263  * doesn't break any clients.
 264  */
 265 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 266                 __be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 267 {
 268         struct nlm_host *host;
 269         struct nlm_rqst *call;
 270         __be32 stat;
 271
 272         host = nlmsvc_lookup_host(rqstp,
 273                                   argp->lock.caller,
 274                                   argp->lock.len);
 275         if (host == NULL)
 276                 return rpc_system_err;
 277
 278         call = nlm_alloc_call(host);
 279         if (call == NULL)
 280                 return rpc_system_err;
 281
 282         stat = func(rqstp, argp, &call->a_res);
 283         if (stat != 0) {
 284                 nlm_release_call(call);
 285                 return stat;
 286         }
 287
 288         call->a_flags = RPC_TASK_ASYNC;
 289         if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
 290                 return rpc_system_err;
 291         return rpc_success;
 292 }
 293
 294 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 295                                              void            *resp)
 296 {
 297         dprintk("lockd: TEST_MSG      called\n");
 298         return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
 299 }
 300
 301 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 302                                              void            *resp)
 303 {
 304         dprintk("lockd: LOCK_MSG      called\n");
 305         return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
 306 }
 307
 308 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 309                                                void            *resp)
 310 {
 311         dprintk("lockd: CANCEL_MSG    called\n");
 312         return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
 313 }
 314
 315 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 316                                                void            *resp)
 317 {
 318         dprintk("lockd: UNLOCK_MSG    called\n");
 319         return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
 320 }
 321
 322 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 323                                                 void            *resp)
 324 {
 325         dprintk("lockd: GRANTED_MSG   called\n");
 326         return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
 327 }
 328
 329 /*
 330  * SHARE: create a DOS share or alter existing share.
 331  */
 332 static __be32
 333 nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 334                                           struct nlm_res  *resp)
 335 {
 336         struct nlm_host *host;
 337         struct nlm_file *file;
 338
 339         dprintk("lockd: SHARE         called\n");
 340
 341         resp->cookie = argp->cookie;
 342
 343         /* Don't accept new lock requests during grace period */
 344         if (nlmsvc_grace_period && !argp->reclaim) {
 345                 resp->status = nlm_lck_denied_grace_period;
 346                 return rpc_success;
 347         }
 348
 349         /* Obtain client and file */
 350         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 351                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 352
 353         /* Now try to create the share */
 354         resp->status = nlmsvc_share_file(host, file, argp);
 355
 356         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 357         nlm_release_host(host);
 358         nlm_release_file(file);
 359         return rpc_success;
 360 }
 361
 362 /*
 363  * UNSHARE: Release a DOS share.
 364  */
 365 static __be32
 366 nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 367                                             struct nlm_res  *resp)
 368 {
 369         struct nlm_host *host;
 370         struct nlm_file *file;
 371
 372         dprintk("lockd: UNSHARE       called\n");
 373
 374         resp->cookie = argp->cookie;
 375
 376         /* Don't accept requests during grace period */
 377         if (nlmsvc_grace_period) {
 378                 resp->status = nlm_lck_denied_grace_period;
 379                 return rpc_success;
 380         }
 381
 382         /* Obtain client and file */
 383         if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 384                 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 385
 386         /* Now try to lock the file */
 387         resp->status = nlmsvc_unshare_file(host, file, argp);
 388
 389         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 390         nlm_release_host(host);
 391         nlm_release_file(file);
 392         return rpc_success;
 393 }
 394
 395 /*
 396  * NM_LOCK: Create an unmonitored lock
 397  */
 398 static __be32
 399 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 400                                             struct nlm_res  *resp)
 401 {
 402         dprintk("lockd: NM_LOCK       called\n");
 403
 404         argp->monitor = 0;              /* just clean the monitor flag */
 405         return nlm4svc_proc_lock(rqstp, argp, resp);
 406 }
 407
 408 /*
 409  * FREE_ALL: Release all locks and shares held by client
 410  */
 411 static __be32
 412 nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 413                                              void            *resp)
 414 {
 415         struct nlm_host *host;
 416
 417         /* Obtain client */
 418         if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
 419                 return rpc_success;
 420
 421         nlmsvc_free_host_resources(host);
 422         nlm_release_host(host);
 423         return rpc_success;
 424 }
 425
 426 /*
 427  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 428  */
 429 static __be32
 430 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 431                                               void              *resp)
 432 {
 433         struct sockaddr_in      saddr;
 434
 435         memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
 436
 437         dprintk("lockd: SM_NOTIFY     called\n");
 438         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 439          || ntohs(saddr.sin_port) >= 1024) {
 440                 char buf[RPC_MAX_ADDRBUFLEN];
 441                 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
 442                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 443                 return rpc_system_err;
 444         }
 445
 446         /* Obtain the host pointer for this NFS server and try to
 447          * reclaim all locks we hold on this server.
 448          */
 449         memset(&saddr, 0, sizeof(saddr));
 450         saddr.sin_addr.s_addr = argp->addr;
 451         nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
 452
 453         return rpc_success;
 454 }
 455
 456 /*
 457  * client sent a GRANTED_RES, let's remove the associated block
 458  */
 459 static __be32
 460 nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 461                                                 void            *resp)
 462 {
 463         if (!nlmsvc_ops)
 464                 return rpc_success;
 465
 466         dprintk("lockd: GRANTED_RES   called\n");
 467
 468         nlmsvc_grant_reply(&argp->cookie, argp->status);
 469         return rpc_success;
 470 }
 471
 472
 473 /*
 474  * NLM Server procedures.
 475  */
 476
 477 #define nlm4svc_encode_norep    nlm4svc_encode_void
 478 #define nlm4svc_decode_norep    nlm4svc_decode_void
 479 #define nlm4svc_decode_testres  nlm4svc_decode_void
 480 #define nlm4svc_decode_lockres  nlm4svc_decode_void
 481 #define nlm4svc_decode_unlockres        nlm4svc_decode_void
 482 #define nlm4svc_decode_cancelres        nlm4svc_decode_void
 483 #define nlm4svc_decode_grantedres       nlm4svc_decode_void
 484
 485 #define nlm4svc_proc_none       nlm4svc_proc_null
 486 #define nlm4svc_proc_test_res   nlm4svc_proc_null
 487 #define nlm4svc_proc_lock_res   nlm4svc_proc_null
 488 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
 489 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
 490
 491 struct nlm_void                 { int dummy; };
 492
 493 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 494  { .pc_func     = (svc_procfunc) nlm4svc_proc_##name,   \
 495    .pc_decode   = (kxdrproc_t) nlm4svc_decode_##xargt,  \
 496    .pc_encode   = (kxdrproc_t) nlm4svc_encode_##xrest,  \
 497    .pc_release  = NULL,                                 \
 498    .pc_argsize  = sizeof(struct nlm_##argt),            \
 499    .pc_ressize  = sizeof(struct nlm_##rest),            \
 500    .pc_xdrressize = respsize,                           \
 501  }
 502 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 503 #define No      (1+1024/4)                              /* netobj */
 504 #define St      1                                       /* status */
 505 #define Rg      4                                       /* range (offset + length) */
 506 struct svc_procedure            nlmsvc_procedures4[] = {
 507   PROC(null,            void,           void,           void,   void, 1),
 508   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 509   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 510   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 511   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 512   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 513   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 514   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 515   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 516   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 517   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 518   PROC(test_res,        testres,        norep,          res,    void, 1),
 519   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 520   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 521   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 522   PROC(granted_res,     res,            norep,          res,    void, 1),
 523   /* statd callback */
 524   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 525   PROC(none,            void,           void,           void,   void, 0),
 526   PROC(none,            void,           void,           void,   void, 0),
 527   PROC(none,            void,           void,           void,   void, 0),
 528   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 529   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 530   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 531   PROC(free_all,        notify,         void,           args,   void, 1),
 532
 533 };