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/config.h>
  11 #include <linux/types.h>
  12 #include <linux/time.h>
  13 #include <linux/slab.h>
  14 #include <linux/in.h>
  15 #include <linux/sunrpc/svc.h>
  16 #include <linux/sunrpc/clnt.h>
  17 #include <linux/nfsd/nfsd.h>
  18 #include <linux/lockd/lockd.h>
  19 #include <linux/lockd/share.h>
  20 #include <linux/lockd/sm_inter.h>
  21
  22
  23 #define NLMDBG_FACILITY         NLMDBG_CLIENT
  24
  25 #ifdef CONFIG_LOCKD_V4
  26 static u32
  27 cast_to_nlm(u32 status, u32 vers)
  28 {
  29         /* Note: status is assumed to be in network byte order !!! */
  30         if (vers != 4){
  31                 switch (status) {
  32                 case nlm_granted:
  33                 case nlm_lck_denied:
  34                 case nlm_lck_denied_nolocks:
  35                 case nlm_lck_blocked:
  36                 case nlm_lck_denied_grace_period:
  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 u32
  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         u32                     error;
  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))
  71          || (argp->monitor && !host->h_monitored && 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         return nlm_lck_denied_nolocks;
  93 }
  94
  95 /*
  96  * NULL: Test for presence of service
  97  */
  98 static int
  99 nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
 100 {
 101         dprintk("lockd: NULL          called\n");
 102         return rpc_success;
 103 }
 104
 105 /*
 106  * TEST: Check for conflicting lock
 107  */
 108 static int
 109 nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
 110                                          struct nlm_res  *resp)
 111 {
 112         struct nlm_host *host;
 113         struct nlm_file *file;
 114
 115         dprintk("lockd: TEST          called\n");
 116         resp->cookie = argp->cookie;
 117
 118         /* Don't accept test requests during grace period */
 119         if (nlmsvc_grace_period) {
 120                 resp->status = nlm_lck_denied_grace_period;
 121                 return rpc_success;
 122         }
 123
 124         /* Obtain client and file */
 125         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 126                 return rpc_success;
 127
 128         /* Now check for conflicting locks */
 129         resp->status = cast_status(nlmsvc_testlock(file, &argp->lock, &resp->lock));
 130
 131         dprintk("lockd: TEST          status %d vers %d\n",
 132                 ntohl(resp->status), rqstp->rq_vers);
 133         nlm_release_host(host);
 134         nlm_release_file(file);
 135         return rpc_success;
 136 }
 137
 138 static int
 139 nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 140                                          struct nlm_res  *resp)
 141 {
 142         struct nlm_host *host;
 143         struct nlm_file *file;
 144
 145         dprintk("lockd: LOCK          called\n");
 146
 147         resp->cookie = argp->cookie;
 148
 149         /* Don't accept new lock requests during grace period */
 150         if (nlmsvc_grace_period && !argp->reclaim) {
 151                 resp->status = nlm_lck_denied_grace_period;
 152                 return rpc_success;
 153         }
 154
 155         /* Obtain client and file */
 156         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 157                 return rpc_success;
 158
 159 #if 0
 160         /* If supplied state doesn't match current state, we assume it's
 161          * an old request that time-warped somehow. Any error return would
 162          * do in this case because it's irrelevant anyway.
 163          *
 164          * NB: We don't retrieve the remote host's state yet.
 165          */
 166         if (host->h_nsmstate && host->h_nsmstate != argp->state) {
 167                 resp->status = nlm_lck_denied_nolocks;
 168         } else
 169 #endif
 170
 171         /* Now try to lock the file */
 172         resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
 173                                                argp->block, &argp->cookie));
 174
 175         dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
 176         nlm_release_host(host);
 177         nlm_release_file(file);
 178         return rpc_success;
 179 }
 180
 181 static int
 182 nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
 183                                            struct nlm_res  *resp)
 184 {
 185         struct nlm_host *host;
 186         struct nlm_file *file;
 187
 188         dprintk("lockd: CANCEL        called\n");
 189
 190         resp->cookie = argp->cookie;
 191
 192         /* Don't accept requests during grace period */
 193         if (nlmsvc_grace_period) {
 194                 resp->status = nlm_lck_denied_grace_period;
 195                 return rpc_success;
 196         }
 197
 198         /* Obtain client and file */
 199         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 200                 return rpc_success;
 201
 202         /* Try to cancel request. */
 203         resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
 204
 205         dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
 206         nlm_release_host(host);
 207         nlm_release_file(file);
 208         return rpc_success;
 209 }
 210
 211 /*
 212  * UNLOCK: release a lock
 213  */
 214 static int
 215 nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
 216                                            struct nlm_res  *resp)
 217 {
 218         struct nlm_host *host;
 219         struct nlm_file *file;
 220
 221         dprintk("lockd: UNLOCK        called\n");
 222
 223         resp->cookie = argp->cookie;
 224
 225         /* Don't accept new lock requests during grace period */
 226         if (nlmsvc_grace_period) {
 227                 resp->status = nlm_lck_denied_grace_period;
 228                 return rpc_success;
 229         }
 230
 231         /* Obtain client and file */
 232         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 233                 return rpc_success;
 234
 235         /* Now try to remove the lock */
 236         resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
 237
 238         dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
 239         nlm_release_host(host);
 240         nlm_release_file(file);
 241         return rpc_success;
 242 }
 243
 244 /*
 245  * GRANTED: A server calls us to tell that a process' lock request
 246  * was granted
 247  */
 248 static int
 249 nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
 250                                             struct nlm_res  *resp)
 251 {
 252         resp->cookie = argp->cookie;
 253
 254         dprintk("lockd: GRANTED       called\n");
 255         resp->status = nlmclnt_grant(&rqstp->rq_addr, &argp->lock);
 256         dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
 257         return rpc_success;
 258 }
 259
 260 /*
 261  * This is the generic lockd callback for async RPC calls
 262  */
 263 static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
 264 {
 265         dprintk("lockd: %4d callback returned %d\n", task->tk_pid,
 266                         -task->tk_status);
 267 }
 268
 269 static void nlmsvc_callback_release(void *data)
 270 {
 271         nlm_release_call(data);
 272 }
 273
 274 static const struct rpc_call_ops nlmsvc_callback_ops = {
 275         .rpc_call_done = nlmsvc_callback_exit,
 276         .rpc_release = nlmsvc_callback_release,
 277 };
 278
 279 /*
 280  * `Async' versions of the above service routines. They aren't really,
 281  * because we send the callback before the reply proper. I hope this
 282  * doesn't break any clients.
 283  */
 284 static int nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
 285                 int (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
 286 {
 287         struct nlm_host *host;
 288         struct nlm_rqst *call;
 289         int stat;
 290
 291         host = nlmsvc_lookup_host(rqstp);
 292         if (host == NULL)
 293                 return rpc_system_err;
 294
 295         call = nlm_alloc_call(host);
 296         if (call == NULL)
 297                 return rpc_system_err;
 298
 299         stat = func(rqstp, argp, &call->a_res);
 300         if (stat != 0) {
 301                 nlm_release_call(call);
 302                 return stat;
 303         }
 304
 305         call->a_flags = RPC_TASK_ASYNC;
 306         if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
 307                 return rpc_system_err;
 308         return rpc_success;
 309 }
 310
 311 static int nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 312                                              void            *resp)
 313 {
 314         dprintk("lockd: TEST_MSG      called\n");
 315         return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
 316 }
 317
 318 static int nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 319                                              void            *resp)
 320 {
 321         dprintk("lockd: LOCK_MSG      called\n");
 322         return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
 323 }
 324
 325 static int nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 326                                                void            *resp)
 327 {
 328         dprintk("lockd: CANCEL_MSG    called\n");
 329         return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
 330 }
 331
 332 static int
 333 nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 334                                                void            *resp)
 335 {
 336         dprintk("lockd: UNLOCK_MSG    called\n");
 337         return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
 338 }
 339
 340 static int
 341 nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
 342                                                 void            *resp)
 343 {
 344         dprintk("lockd: GRANTED_MSG   called\n");
 345         return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
 346 }
 347
 348 /*
 349  * SHARE: create a DOS share or alter existing share.
 350  */
 351 static int
 352 nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
 353                                           struct nlm_res  *resp)
 354 {
 355         struct nlm_host *host;
 356         struct nlm_file *file;
 357
 358         dprintk("lockd: SHARE         called\n");
 359
 360         resp->cookie = argp->cookie;
 361
 362         /* Don't accept new lock requests during grace period */
 363         if (nlmsvc_grace_period && !argp->reclaim) {
 364                 resp->status = nlm_lck_denied_grace_period;
 365                 return rpc_success;
 366         }
 367
 368         /* Obtain client and file */
 369         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 370                 return rpc_success;
 371
 372         /* Now try to create the share */
 373         resp->status = cast_status(nlmsvc_share_file(host, file, argp));
 374
 375         dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
 376         nlm_release_host(host);
 377         nlm_release_file(file);
 378         return rpc_success;
 379 }
 380
 381 /*
 382  * UNSHARE: Release a DOS share.
 383  */
 384 static int
 385 nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
 386                                             struct nlm_res  *resp)
 387 {
 388         struct nlm_host *host;
 389         struct nlm_file *file;
 390
 391         dprintk("lockd: UNSHARE       called\n");
 392
 393         resp->cookie = argp->cookie;
 394
 395         /* Don't accept requests during grace period */
 396         if (nlmsvc_grace_period) {
 397                 resp->status = nlm_lck_denied_grace_period;
 398                 return rpc_success;
 399         }
 400
 401         /* Obtain client and file */
 402         if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
 403                 return rpc_success;
 404
 405         /* Now try to unshare the file */
 406         resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
 407
 408         dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
 409         nlm_release_host(host);
 410         nlm_release_file(file);
 411         return rpc_success;
 412 }
 413
 414 /*
 415  * NM_LOCK: Create an unmonitored lock
 416  */
 417 static int
 418 nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
 419                                             struct nlm_res  *resp)
 420 {
 421         dprintk("lockd: NM_LOCK       called\n");
 422
 423         argp->monitor = 0;              /* just clean the monitor flag */
 424         return nlmsvc_proc_lock(rqstp, argp, resp);
 425 }
 426
 427 /*
 428  * FREE_ALL: Release all locks and shares held by client
 429  */
 430 static int
 431 nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
 432                                              void            *resp)
 433 {
 434         struct nlm_host *host;
 435
 436         /* Obtain client */
 437         if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
 438                 return rpc_success;
 439
 440         nlmsvc_free_host_resources(host);
 441         nlm_release_host(host);
 442         return rpc_success;
 443 }
 444
 445 /*
 446  * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 447  */
 448 static int
 449 nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
 450                                               void              *resp)
 451 {
 452         struct sockaddr_in      saddr = rqstp->rq_addr;
 453         int                     vers = argp->vers;
 454         int                     prot = argp->proto >> 1;
 455         struct nlm_host         *host;
 456
 457         dprintk("lockd: SM_NOTIFY     called\n");
 458         if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
 459          || ntohs(saddr.sin_port) >= 1024) {
 460                 printk(KERN_WARNING
 461                         "lockd: rejected NSM callback from %08x:%d\n",
 462                         ntohl(rqstp->rq_addr.sin_addr.s_addr),
 463                         ntohs(rqstp->rq_addr.sin_port));
 464                 return rpc_system_err;
 465         }
 466
 467         /* Obtain the host pointer for this NFS server and try to
 468          * reclaim all locks we hold on this server.
 469          */
 470         saddr.sin_addr.s_addr = argp->addr;
 471         if ((argp->proto & 1)==0) {
 472                 if ((host = nlmclnt_lookup_host(&saddr, prot, vers)) != NULL) {
 473                         nlmclnt_recovery(host, argp->state);
 474                         nlm_release_host(host);
 475                 }
 476         } else {
 477                 /* If we run on an NFS server, delete all locks held by the client */
 478                 if ((host = nlm_lookup_host(1, &saddr, prot, vers)) != NULL) {
 479                         nlmsvc_free_host_resources(host);
 480                         nlm_release_host(host);
 481                 }
 482         }
 483
 484         return rpc_success;
 485 }
 486
 487 /*
 488  * client sent a GRANTED_RES, let's remove the associated block
 489  */
 490 static int
 491 nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
 492                                                 void            *resp)
 493 {
 494         if (!nlmsvc_ops)
 495                 return rpc_success;
 496
 497         dprintk("lockd: GRANTED_RES   called\n");
 498
 499         nlmsvc_grant_reply(rqstp, &argp->cookie, argp->status);
 500         return rpc_success;
 501 }
 502
 503 /*
 504  * NLM Server procedures.
 505  */
 506
 507 #define nlmsvc_encode_norep     nlmsvc_encode_void
 508 #define nlmsvc_decode_norep     nlmsvc_decode_void
 509 #define nlmsvc_decode_testres   nlmsvc_decode_void
 510 #define nlmsvc_decode_lockres   nlmsvc_decode_void
 511 #define nlmsvc_decode_unlockres nlmsvc_decode_void
 512 #define nlmsvc_decode_cancelres nlmsvc_decode_void
 513 #define nlmsvc_decode_grantedres        nlmsvc_decode_void
 514
 515 #define nlmsvc_proc_none        nlmsvc_proc_null
 516 #define nlmsvc_proc_test_res    nlmsvc_proc_null
 517 #define nlmsvc_proc_lock_res    nlmsvc_proc_null
 518 #define nlmsvc_proc_cancel_res  nlmsvc_proc_null
 519 #define nlmsvc_proc_unlock_res  nlmsvc_proc_null
 520
 521 struct nlm_void                 { int dummy; };
 522
 523 #define PROC(name, xargt, xrest, argt, rest, respsize)  \
 524  { .pc_func     = (svc_procfunc) nlmsvc_proc_##name,    \
 525    .pc_decode   = (kxdrproc_t) nlmsvc_decode_##xargt,   \
 526    .pc_encode   = (kxdrproc_t) nlmsvc_encode_##xrest,   \
 527    .pc_release  = NULL,                                 \
 528    .pc_argsize  = sizeof(struct nlm_##argt),            \
 529    .pc_ressize  = sizeof(struct nlm_##rest),            \
 530    .pc_xdrressize = respsize,                           \
 531  }
 532
 533 #define Ck      (1+XDR_QUADLEN(NLM_MAXCOOKIELEN))       /* cookie */
 534 #define St      1                               /* status */
 535 #define No      (1+1024/4)                      /* Net Obj */
 536 #define Rg      2                               /* range - offset + size */
 537
 538 struct svc_procedure            nlmsvc_procedures[] = {
 539   PROC(null,            void,           void,           void,   void, 1),
 540   PROC(test,            testargs,       testres,        args,   res, Ck+St+2+No+Rg),
 541   PROC(lock,            lockargs,       res,            args,   res, Ck+St),
 542   PROC(cancel,          cancargs,       res,            args,   res, Ck+St),
 543   PROC(unlock,          unlockargs,     res,            args,   res, Ck+St),
 544   PROC(granted,         testargs,       res,            args,   res, Ck+St),
 545   PROC(test_msg,        testargs,       norep,          args,   void, 1),
 546   PROC(lock_msg,        lockargs,       norep,          args,   void, 1),
 547   PROC(cancel_msg,      cancargs,       norep,          args,   void, 1),
 548   PROC(unlock_msg,      unlockargs,     norep,          args,   void, 1),
 549   PROC(granted_msg,     testargs,       norep,          args,   void, 1),
 550   PROC(test_res,        testres,        norep,          res,    void, 1),
 551   PROC(lock_res,        lockres,        norep,          res,    void, 1),
 552   PROC(cancel_res,      cancelres,      norep,          res,    void, 1),
 553   PROC(unlock_res,      unlockres,      norep,          res,    void, 1),
 554   PROC(granted_res,     res,            norep,          res,    void, 1),
 555   /* statd callback */
 556   PROC(sm_notify,       reboot,         void,           reboot, void, 1),
 557   PROC(none,            void,           void,           void,   void, 1),
 558   PROC(none,            void,           void,           void,   void, 1),
 559   PROC(none,            void,           void,           void,   void, 1),
 560   PROC(share,           shareargs,      shareres,       args,   res, Ck+St+1),
 561   PROC(unshare,         shareargs,      shareres,       args,   res, Ck+St+1),
 562   PROC(nm_lock,         lockargs,       res,            args,   res, Ck+St),
 563   PROC(free_all,        notify,         void,           args,   void, 0),
 564
 565 };