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