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 u32
  26 cast_to_nlm(u32 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                         break;
  37                 case nlm4_deadlock:
  38                         status = nlm_lck_denied;
  39                         break;
  40                 default:
  41                         status = nlm_lck_denied_nolocks;
  42                 }
  43         }
  44
  45         return (status);
  46 }
  47 #define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
  48 #else
  49 #define cast_status(status) (status)
  50 #endif
  51
  52 /*
  53  * Obtain client and file from arguments
  54  */
  55 static u32
  56 nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  57                         struct nlm_host **hostp, struct nlm_file **filp)
  58 {
  59         struct nlm_host         *host = NULL;
  60         struct nlm_file         *file = NULL;
  61         struct nlm_lock         *lock = &argp->lock;
  62         u32                     error;
  63
  64         /* nfsd callbacks must have been installed for this procedure */
  65         if (!nlmsvc_ops)
  66                 return nlm_lck_denied_nolocks;
  67
  68         /* Obtain host handle */
  69         if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  70          || (argp->monitor && nsm_monitor(host) < 0))
  71                 goto no_locks;
  72         *hostp = host;
  73
  74         /* Obtain file pointer. Not used by FREE_ALL call. */
  75         if (filp != NULL) {
  76                 if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  77                         goto no_locks;
  78                 *filp = file;
  79
  80                 /* Set up the missing parts of the file_lock structure */
  81                 lock->fl.fl_file  = file->f_file;
  82                 lock->fl.fl_owner = (fl_owner_t) host;
  83                 lock->fl.fl_lmops = &nlmsvc_lock_operations;
  84         }
  85
  86         return 0;
  87
  88 no_locks:
  89         if (host)
  90                 nlm_release_host(host);
  91         return nlm_lck_denied_nolocks;
  92 }
  93
  94 /*
  95  * NULL: Test for presence of service
  96  */
  97 static int
  98 nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  99 {
 100         dprintk("lockd: NULL          called\n");
 101         return rpc_success;
 102 }
 103
 104 /*
 105  * TEST: Check for conflicting lock
 106  */
 107 static int
 108 nlmsvc_proc_test(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
 114         dprintk("lockd: TEST          called\n");
 115         resp->cookie = argp->cookie;
 116
 117         /* Don't accept test requests during grace period */
 118         if (nlmsvc_grace_period) {
 119                 resp->status = nlm_lck_denied_grace_period;
 120                 return rpc_success;
 121         }
 122
 123         /* Obtain client and file */
 124         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 125                 return rpc_success;
 126
 127         /* Now check for conflicting locks */
 128         resp->status = cast_status(nlmsvc_testlock(file, &argp->lock, &resp->lock));
 129
 130         dprintk("lockd: TEST          status %d vers %d\n",
 131                 ntohl(resp->status), rqstp->rq_vers);
 132         nlm_release_host(host);
 133         nlm_release_file(file);
 134         return rpc_success;
 135 }
 136
 137 static int
 138 nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 139                                          struct nlm_res  *resp)
 140 {
 141         struct nlm_host *host;
 142         struct nlm_file *file;
 143
 144         dprintk("lockd: LOCK          called\n");
 145
 146         resp->cookie = argp->cookie;
 147
 148         /* Don't accept new lock requests during grace period */
 149         if (nlmsvc_grace_period && !argp->reclaim) {
 150                 resp->status = nlm_lck_denied_grace_period;
 151                 return rpc_success;
 152         }
 153
 154         /* Obtain client and file */
 155         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 156                 return rpc_success;
 157
 158 #if 0
 159         /* If supplied state doesn't match current state, we assume it's
 160          * an old request that time-warped somehow. Any error return would
 161          * do in this case because it's irrelevant anyway.
 162          *
 163          * NB: We don't retrieve the remote host's state yet.
 164          */
 165         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 166                 resp->status = nlm_lck_denied_nolocks;
 167         } else
 168 #endif
 169
 170         /* Now try to lock the file */
 171         resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
 172                                                argp->block, &argp->cookie));
 173
 174         dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
 175         nlm_release_host(host);
 176         nlm_release_file(file);
 177         return rpc_success;
 178 }
 179
 180 static int
 181 nlmsvc_proc_cancel(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: CANCEL        called\n");
 188
 189         resp->cookie = argp->cookie;
 190
 191         /* Don't accept requests during grace period */
 192         if (nlmsvc_grace_period) {
 193                 resp->status = nlm_lck_denied_grace_period;
 194                 return rpc_success;
 195         }
 196
 197         /* Obtain client and file */
 198         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 199                 return rpc_success;
 200
 201         /* Try to cancel request. */
 202         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 203
 204         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 205         nlm_release_host(host);
 206         nlm_release_file(file);
 207         return rpc_success;
 208 }
 209
 210 /*
 211  * UNLOCK: release a lock
 212  */
 213 static int
 214 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 215                                            struct nlm_res  *resp)
 216 {
 217         struct nlm_host *host;
 218         struct nlm_file *file;
 219
 220         dprintk("lockd: UNLOCK        called\n");
 221
 222         resp->cookie = argp->cookie;
 223
 224         /* Don't accept new lock requests during grace period */
 225         if (nlmsvc_grace_period) {
 226                 resp->status = nlm_lck_denied_grace_period;
 227                 return rpc_success;
 228         }
 229
 230         /* Obtain client and file */
 231         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 232                 return rpc_success;
 233
 234         /* Now try to remove the lock */
 235         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 236
 237         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 238         nlm_release_host(host);
 239         nlm_release_file(file);
 240         return rpc_success;
 241 }
 242
 243 /*
 244  * GRANTED: A server calls us to tell that a process' lock request
 245  * was granted
 246  */
 247 static int
 248 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 249                                             struct nlm_res  *resp)
 250 {
 251         resp->cookie = argp->cookie;
 252
 253         dprintk("lockd: GRANTED       called\n");
 254         resp->status = nlmclnt_grant(&rqstp->rq_addr, &argp->lock);
 255         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 256         return rpc_success;
 257 }
 258
 259 /*
 260  * This is the generic lockd callback for async RPC calls
 261  */
 262 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 263 {
 264         dprintk("lockd: %4d callback returned %d\n", task->tk_pid,
 265                         -task->tk_status);
 266 }
 267
 268 static void nlmsvc_callback_release(void *data)
 269 {
 270         nlm_release_call(data);
 271 }
 272
 273 static const struct rpc_call_ops nlmsvc_callback_ops = {
 274         .rpc_call_done = nlmsvc_callback_exit,
 275         .rpc_release = nlmsvc_callback_release,
 276 };
 277
 278 /*
 279  * `Async' versions of the above service routines. They aren't really,
 280  * because we send the callback before the reply proper. I hope this
 281  * doesn't break any clients.
 282  */
 283 static int nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 284                 int (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 285 {
 286         struct nlm_host *host;
 287         struct nlm_rqst *call;
 288         int stat;
 289
 290         host = nlmsvc_lookup_host(rqstp,
 291                                   argp->lock.caller,
 292                                   argp->lock.len);
 293         if (host == NULL)
 294                 return rpc_system_err;
 295
 296         call = nlm_alloc_call(host);
 297         if (call == NULL)
 298                 return rpc_system_err;
 299
 300         stat = func(rqstp, argp, &call->a_res);
 301         if (stat != 0) {
 302                 nlm_release_call(call);
 303                 return stat;
 304         }
 305
 306         call->a_flags = RPC_TASK_ASYNC;
 307         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 308                 return rpc_system_err;
 309         return rpc_success;
 310 }
 311
 312 static int nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 313                                              void            *resp)
 314 {
 315         dprintk("lockd: TEST_MSG      called\n");
 316         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 317 }
 318
 319 static int nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 320                                              void            *resp)
 321 {
 322         dprintk("lockd: LOCK_MSG      called\n");
 323         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 324 }
 325
 326 static int nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 327                                                void            *resp)
 328 {
 329         dprintk("lockd: CANCEL_MSG    called\n");
 330         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 331 }
 332
 333 static int
 334 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 335                                                void            *resp)
 336 {
 337         dprintk("lockd: UNLOCK_MSG    called\n");
 338         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 339 }
 340
 341 static int
 342 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 343                                                 void            *resp)
 344 {
 345         dprintk("lockd: GRANTED_MSG   called\n");
 346         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 347 }
 348
 349 /*
 350  * SHARE: create a DOS share or alter existing share.
 351  */
 352 static int
 353 nlmsvc_proc_share(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: SHARE         called\n");
 360
 361         resp->cookie = argp->cookie;
 362
 363         /* Don't accept new lock requests during grace period */
 364         if (nlmsvc_grace_period && !argp->reclaim) {
 365                 resp->status = nlm_lck_denied_grace_period;
 366                 return rpc_success;
 367         }
 368
 369         /* Obtain client and file */
 370         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 371                 return rpc_success;
 372
 373         /* Now try to create the share */
 374         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 375
 376         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 377         nlm_release_host(host);
 378         nlm_release_file(file);
 379         return rpc_success;
 380 }
 381
 382 /*
 383  * UNSHARE: Release a DOS share.
 384  */
 385 static int
 386 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 387                                             struct nlm_res  *resp)
 388 {
 389         struct nlm_host *host;
 390         struct nlm_file *file;
 391
 392         dprintk("lockd: UNSHARE       called\n");
 393
 394         resp->cookie = argp->cookie;
 395
 396         /* Don't accept requests during grace period */
 397         if (nlmsvc_grace_period) {
 398                 resp->status = nlm_lck_denied_grace_period;
 399                 return rpc_success;
 400         }
 401
 402         /* Obtain client and file */
 403         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 404                 return rpc_success;
 405
 406         /* Now try to unshare the file */
 407         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 408
 409         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 410         nlm_release_host(host);
 411         nlm_release_file(file);
 412         return rpc_success;
 413 }
 414
 415 /*
 416  * NM_LOCK: Create an unmonitored lock
 417  */
 418 static int
 419 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 420                                             struct nlm_res  *resp)
 421 {
 422         dprintk("lockd: NM_LOCK       called\n");
 423
 424         argp->monitor = 0;              /* just clean the monitor flag */
 425         return nlmsvc_proc_lock(rqstp, argp, resp);
 426 }
 427
 428 /*
 429  * FREE_ALL: Release all locks and shares held by client
 430  */
 431 static int
 432 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 433                                              void            *resp)
 434 {
 435         struct nlm_host *host;
 436
 437         /* Obtain client */
 438         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 439                 return rpc_success;
 440
 441         nlmsvc_free_host_resources(host);
 442         nlm_release_host(host);
 443         return rpc_success;
 444 }
 445
 446 /*
 447  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 448  */
 449 static int
 450 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 451                                               void              *resp)
 452 {
 453         struct sockaddr_in      saddr = rqstp->rq_addr;
 454
 455         dprintk("lockd: SM_NOTIFY     called\n");
 456         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 457          || ntohs(saddr.sin_port) >= 1024) {
 458                 printk(KERN_WARNING
 459                         "lockd: rejected NSM callback from %08x:%d\n",
 460                         ntohl(rqstp->rq_addr.sin_addr.s_addr),
 461                         ntohs(rqstp->rq_addr.sin_port));
 462                 return rpc_system_err;
 463         }
 464
 465         /* Obtain the host pointer for this NFS server and try to
 466          * reclaim all locks we hold on this server.
 467          */
 468         memset(&saddr, 0, sizeof(saddr));
 469         saddr.sin_addr.s_addr = argp->addr;
 470         nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
 471
 472         return rpc_success;
 473 }
 474
 475 /*
 476  * client sent a GRANTED_RES, let's remove the associated block
 477  */
 478 static int
 479 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 480                                                 void            *resp)
 481 {
 482         if (!nlmsvc_ops)
 483                 return rpc_success;
 484
 485         dprintk("lockd: GRANTED_RES   called\n");
 486
 487         nlmsvc_grant_reply(&argp->cookie, argp->status);
 488         return rpc_success;
 489 }
 490
 491 /*
 492  * NLM Server procedures.
 493  */
 494
 495 #define nlmsvc_encode_norep     nlmsvc_encode_void
 496 #define nlmsvc_decode_norep     nlmsvc_decode_void
 497 #define nlmsvc_decode_testres   nlmsvc_decode_void
 498 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 499 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 500 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 501 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 502
 503 #define nlmsvc_proc_none        nlmsvc_proc_null
 504 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 505 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 506 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 507 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 508
 509 struct nlm_void                 { int dummy; };
 510
 511 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 512  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 513    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 514    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 515    .pc_release  = NULL,                                 \
 516    .pc_argsize  = sizeof(struct nlm_##argt),            \
 517    .pc_ressize  = sizeof(struct nlm_##rest),            \
 518    .pc_xdrressize = respsize,                           \
 519  }
 520
 521 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 522 #define St      1                               /* status */
 523 #define No      (1+1024/4)                      /* Net Obj */
 524 #define Rg      2                               /* range - offset + size */
 525
 526 struct svc_procedure            nlmsvc_procedures[] = {
 527   PROC(null,            void,           void,           void,   void, 1),
 528   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 529   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 530   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 531   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 532   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 533   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 534   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 535   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 536   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 537   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 538   PROC(test_res,        testres,        norep,          res,    void, 1),
 539   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 540   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 541   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 542   PROC(granted_res,     res,            norep,          res,    void, 1),
 543   /* statd callback */
 544   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 545   PROC(none,            void,           void,           void,   void, 1),
 546   PROC(none,            void,           void,           void,   void, 1),
 547   PROC(none,            void,           void,           void,   void, 1),
 548   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 549   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 550   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 551   PROC(free_all,        notify,         void,           args,   void, 0),
 552
 553 };