source3/modules/onefs_cbrl.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Support for OneFS system interfaces.
   4  *
   5  * Copyright (C) Zack Kirsch, 2009
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "includes.h"
  22 #include "onefs.h"
  23
  24 #include <ifs/ifs_syscalls.h>
  25 #include <sys/isi_cifs_brl.h>
  26 #include <isi_ecs/isi_ecs_cbrl.h>
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_LOCKING
  30
  31 static uint64_t onefs_get_new_id(void) {
  32         static uint64_t id = 0;
  33
  34         id++;
  35
  36         return id;
  37 }
  38
  39 enum onefs_cbrl_lock_state {ONEFS_CBRL_NONE, ONEFS_CBRL_ASYNC, ONEFS_CBRL_DONE,
  40         ONEFS_CBRL_ERROR};
  41
  42 struct onefs_cbrl_blr_state {
  43         uint64_t id;
  44         enum onefs_cbrl_lock_state state;
  45 };
  46
  47 static char *onefs_cbrl_blr_state_str(const struct blocking_lock_record *blr)
  48 {
  49         static fstring result;
  50         struct onefs_cbrl_blr_state *bs;
  51
  52         SMB_ASSERT(blr);
  53
  54         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
  55
  56         if (bs == NULL) {
  57                 fstrcpy(result, "NULL CBRL BLR state - Posix lock?");
  58                 return result;
  59         }
  60
  61         switch (bs->state) {
  62         case ONEFS_CBRL_NONE:
  63                 fstr_sprintf(result, "CBRL BLR id=%llu: state=NONE", bs->id);
  64                 break;
  65         case ONEFS_CBRL_ASYNC:
  66                 fstr_sprintf(result, "CBRL BLR id=%llu: state=ASYNC", bs->id);
  67                 break;
  68         case ONEFS_CBRL_DONE:
  69                 fstr_sprintf(result, "CBRL BLR id=%llu: state=DONE", bs->id);
  70                 break;
  71         case ONEFS_CBRL_ERROR:
  72                 fstr_sprintf(result, "CBRL BLR id=%llu: state=ERROR", bs->id);
  73                 break;
  74         default:
  75                 fstr_sprintf(result, "CBRL BLR id=%llu: unknown state %d",
  76                     bs->id, bs->state);
  77                 break;
  78         }
  79
  80         return result;
  81 }
  82
  83 static void onefs_cbrl_enumerate_blq(const char *fn)
  84 {
  85         struct smbd_server_connection *sconn = smbd_server_conn;
  86         struct blocking_lock_record *blr;
  87
  88         if (DEBUGLVL(10))
  89                 return;
  90
  91         DEBUG(10, ("CBRL BLR records (%s):\n", fn));
  92
  93         if (sconn->allow_smb2) {
  94                 struct smbd_smb2_request *smb2req;
  95                 for (smb2req = sconn->smb2.requests; smb2req; smb2req = nextreq) {
  96                         blr = get_pending_smb2req_blr(smb2req);
  97                         if (blr) {
  98                                 DEBUGADD(10, ("%s\n", onefs_cbrl_blr_state_str(blr)));
  99                         }
 100                 }
 101         } else {
 102                 for (blr = sconn->smb1.locks.blocking_lock_queue; blr; blr = blr->next)
 103                         DEBUGADD(10, ("%s\n", onefs_cbrl_blr_state_str(blr)));
 104         }
 105 }
 106
 107 static struct blocking_lock_record *onefs_cbrl_find_blr(uint64_t id)
 108 {
 109         struct smbd_server_connection *sconn = smbd_server_conn;
 110         struct blocking_lock_record *blr;
 111         struct onefs_cbrl_blr_state *bs;
 112
 113         onefs_cbrl_enumerate_blq("onefs_cbrl_find_blr");
 114
 115         if (sconn->allow_smb2) {
 116                 struct smbd_smb2_request *smb2req;
 117                 for (smb2req = sconn->smb2.requests; smb2req; smb2req = nextreq) {
 118                         blr = get_pending_smb2req_blr(smb2req);
 119                         if (!blr) {
 120                                 continue;
 121                         }
 122                         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 123                         if (bs == NULL) {
 124                                 continue;
 125                         }
 126                         if (bs->id == id) {
 127                                 DEBUG(10, ("found %s\n",
 128                                     onefs_cbrl_blr_state_str(blr)));
 129                                 break;
 130                         }
 131         } else {
 132                 for (blr = sconn->smb1.locks.blocking_lock_queue; blr; blr = blr->next) {
 133                         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 134
 135                         /* We don't control all of the BLRs on the BLQ. */
 136                         if (bs == NULL)
 137                                 continue;
 138
 139                         if (bs->id == id) {
 140                                 DEBUG(10, ("found %s\n",
 141                                     onefs_cbrl_blr_state_str(blr)));
 142                                 break;
 143                         }
 144                 }
 145         }
 146
 147         if (blr == NULL) {
 148                 DEBUG(5, ("Could not find CBRL BLR for id %llu\n", id));
 149                 return NULL;
 150         }
 151
 152         return blr;
 153 }
 154
 155 static void onefs_cbrl_async_success(uint64_t id)
 156 {
 157         struct blocking_lock_record *blr;
 158         struct onefs_cbrl_blr_state *bs;
 159         uint16 num_locks;
 160
 161         DEBUG(10, ("CBRL async success!\n"));
 162
 163         /* Find BLR with id. Its okay not to find one (race with cancel) */
 164         blr = onefs_cbrl_find_blr(id);
 165         if (blr == NULL)
 166                 return;
 167
 168         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 169         SMB_ASSERT(bs);
 170         SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);
 171
 172         blr->lock_num++;
 173
 174         num_locks = SVAL(blr->req->vwv+7, 0);
 175
 176         if (blr->lock_num == num_locks)
 177                 bs->state = ONEFS_CBRL_DONE;
 178         else
 179                 bs->state = ONEFS_CBRL_NONE;
 180
 181         /* Self contend our own level 2 oplock. The kernel handles
 182          * contention of other opener's level 2 oplocks. */
 183         contend_level2_oplocks_begin(blr->fsp,
 184             LEVEL2_CONTEND_WINDOWS_BRL);
 185
 186         /* Process the queue, to try the next lock or finish up. */
 187         process_blocking_lock_queue();
 188 }
 189
 190 static void onefs_cbrl_async_failure(uint64_t id)
 191 {
 192         struct blocking_lock_record *blr;
 193         struct onefs_cbrl_blr_state *bs;
 194
 195         DEBUG(10, ("CBRL async failure!\n"));
 196
 197         /* Find BLR with id. Its okay not to find one (race with cancel) */
 198         blr = onefs_cbrl_find_blr(id);
 199         if (blr == NULL)
 200                 return;
 201
 202         bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 203         SMB_ASSERT(bs);
 204
 205         SMB_ASSERT(bs->state == ONEFS_CBRL_ASYNC);
 206         bs->state = ONEFS_CBRL_ERROR;
 207
 208         /* Process the queue. It will end up trying to retake the same lock,
 209          * see the error in onefs_cbrl_lock_windows() and fail. */
 210         process_blocking_lock_queue();
 211 }
 212
 213 static struct cbrl_event_ops cbrl_ops =
 214     {.cbrl_async_success = onefs_cbrl_async_success,
 215      .cbrl_async_failure = onefs_cbrl_async_failure};
 216
 217 static void onefs_cbrl_events_handler(struct event_context *ev,
 218                                         struct fd_event *fde,
 219                                         uint16_t flags,
 220                                         void *private_data)
 221 {
 222         DEBUG(10, ("onefs_cbrl_events_handler\n"));
 223
 224         if (cbrl_event_dispatcher(&cbrl_ops)) {
 225                 DEBUG(0, ("cbrl_event_dispatcher failed: %s\n",
 226                         strerror(errno)));
 227         }
 228 }
 229
 230 static void onefs_init_cbrl(void)
 231 {
 232         static bool init_done = false;
 233         static int cbrl_event_fd;
 234         static struct fd_event *cbrl_fde;
 235
 236         if (init_done)
 237                 return;
 238
 239         DEBUG(10, ("onefs_init_cbrl\n"));
 240
 241         /* Register the event channel for CBRL. */
 242         cbrl_event_fd = cbrl_event_register();
 243         if (cbrl_event_fd == -1) {
 244                 DEBUG(0, ("cbrl_event_register failed: %s\n",
 245                         strerror(errno)));
 246                 return;
 247         }
 248
 249         DEBUG(10, ("cbrl_event_fd = %d\n", cbrl_event_fd));
 250
 251         /* Register the CBRL event_fd with samba's event system */
 252         cbrl_fde = event_add_fd(smbd_event_context(),
 253                                      NULL,
 254                                      cbrl_event_fd,
 255                                      EVENT_FD_READ,
 256                                      onefs_cbrl_events_handler,
 257                                      NULL);
 258
 259         init_done = true;
 260         return;
 261 }
 262
 263 /**
 264  * Blocking PID. As far as I can tell, the blocking_pid is only used to tell
 265  * whether a posix lock or a CIFS lock blocked us. If it was a posix lock,
 266  * Samba polls every 10 seconds, which we don't want. -zkirsch
 267  */
 268 #define ONEFS_BLOCKING_PID 0xABCDABCD
 269
 270 /**
 271  * @param[in]     br_lck        Contains the fsp.
 272  * @param[in]     plock         Lock request.
 273  * @param[in]     blocking_lock Only used for figuring out the error.
 274  * @param[in,out] blr           The BLR for the already-deferred operation.
 275  */
 276 NTSTATUS onefs_brl_lock_windows(vfs_handle_struct *handle,
 277                                 struct byte_range_lock *br_lck,
 278                                 struct lock_struct *plock,
 279                                 bool blocking_lock,
 280                                 struct blocking_lock_record *blr)
 281 {
 282         int fd = br_lck->fsp->fh->fd;
 283         uint64_t id = 0;
 284         enum cbrl_lock_type type;
 285         bool async = false;
 286         bool pending = false;
 287         bool pending_async = false;
 288         int error;
 289         struct onefs_cbrl_blr_state *bs;
 290         NTSTATUS status;
 291
 292         START_PROFILE(syscall_brl_lock);
 293
 294         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 295         SMB_ASSERT(plock->lock_type != UNLOCK_LOCK);
 296
 297         onefs_cbrl_enumerate_blq("onefs_brl_lock_windows");
 298
 299         /* Will only initialize the first time its called. */
 300         onefs_init_cbrl();
 301
 302         switch (plock->lock_type) {
 303                 case WRITE_LOCK:
 304                         type = CBRL_LK_EX;
 305                         break;
 306                 case READ_LOCK:
 307                         type = CBRL_LK_SH;
 308                         break;
 309                 case PENDING_WRITE_LOCK:
 310                         /* Called when a blocking lock request is added - do an
 311                          * async lock. */
 312                         type = CBRL_LK_EX;
 313                         pending = true;
 314                         async = true;
 315                         break;
 316                 case PENDING_READ_LOCK:
 317                         /* Called when a blocking lock request is added - do an
 318                          * async lock. */
 319                         type = CBRL_LK_SH;
 320                         pending = true;
 321                         async = true;
 322                         break;
 323                 default:
 324                         /* UNLOCK_LOCK: should only be used for a POSIX_LOCK */
 325                         smb_panic("Invalid plock->lock_type passed in to "
 326                             "onefs_brl_lock_windows");
 327         }
 328
 329         /* Figure out if we're actually doing the lock or a no-op. We need to
 330          * do a no-op when process_blocking_lock_queue calls back into us.
 331          *
 332          * We know process_* is calling into us if a blr is passed in and
 333          * pending is false. */
 334         if (!pending && blr) {
 335                 /* Check the BLR state. */
 336                 bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 337                 SMB_ASSERT(bs);
 338
 339                 /* ASYNC still in progress: The process_* calls will keep
 340                  * calling even if we haven't gotten the lock. Keep erroring
 341                  * without calling ifs_cbrl, or getting/setting an id. */
 342                 if (bs->state == ONEFS_CBRL_ASYNC) {
 343                         goto failure;
 344                 }
 345                 else if (bs->state == ONEFS_CBRL_ERROR) {
 346                         END_PROFILE(syscall_brl_lock);
 347                         return NT_STATUS_NO_MEMORY;
 348                 }
 349
 350                 SMB_ASSERT(bs->state == ONEFS_CBRL_NONE);
 351                 async = true;
 352         }
 353
 354         if (async) {
 355                 SMB_ASSERT(blocking_lock);
 356                 SMB_ASSERT(blr);
 357                 id = onefs_get_new_id();
 358         }
 359
 360         DEBUG(10, ("Calling ifs_cbrl(LOCK)...\n"));
 361         error = ifs_cbrl(fd, CBRL_OP_LOCK, type, plock->start,
 362             plock->size, async, id, plock->context.smbpid, plock->context.tid,
 363             plock->fnum);
 364         if (!error) {
 365                 goto success;
 366         } else if (errno == EWOULDBLOCK) {
 367                 SMB_ASSERT(!async);
 368         } else if (errno == EINPROGRESS) {
 369                 SMB_ASSERT(async);
 370
 371                 if (pending) {
 372                         /* Talloc a new BLR private state. */
 373                         blr->blr_private = talloc(blr, struct onefs_cbrl_blr_state);
 374                         pending_async = true;
 375                 }
 376
 377                 /* Store the new id in the BLR private state. */
 378                 bs = (struct onefs_cbrl_blr_state *)blr->blr_private;
 379                 bs->id = id;
 380                 bs->state = ONEFS_CBRL_ASYNC;
 381         } else {
 382                 DEBUG(0, ("onefs_brl_lock_windows failure: error=%d (%s).\n",
 383                         errno, strerror(errno)));
 384         }
 385
 386 failure:
 387
 388         END_PROFILE(syscall_brl_lock);
 389
 390         /* Failure - error or async. */
 391         plock->context.smbpid = (uint32) ONEFS_BLOCKING_PID;
 392
 393         if (pending_async)
 394                 status = NT_STATUS_OK;
 395         else
 396                 status = brl_lock_failed(br_lck->fsp, plock, blocking_lock);
 397
 398         DEBUG(10, ("returning %s.\n", nt_errstr(status)));
 399         return status;
 400
 401 success:
 402         /* Self contend our own level 2 oplock. The kernel handles
 403          * contention of other opener's level 2 oplocks. */
 404         contend_level2_oplocks_begin(br_lck->fsp,
 405             LEVEL2_CONTEND_WINDOWS_BRL);
 406
 407         END_PROFILE(syscall_brl_lock);
 408
 409         /* Success. */
 410         onefs_cbrl_enumerate_blq("onefs_brl_unlock_windows");
 411         DEBUG(10, ("returning NT_STATUS_OK.\n"));
 412         return NT_STATUS_OK;
 413 }
 414
 415 bool onefs_brl_unlock_windows(vfs_handle_struct *handle,
 416                               struct messaging_context *msg_ctx,
 417                               struct byte_range_lock *br_lck,
 418                               const struct lock_struct *plock)
 419 {
 420         int error;
 421         int fd = br_lck->fsp->fh->fd;
 422
 423         START_PROFILE(syscall_brl_unlock);
 424
 425         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 426         SMB_ASSERT(plock->lock_type == UNLOCK_LOCK);
 427
 428         DEBUG(10, ("Calling ifs_cbrl(UNLOCK)...\n"));
 429         error = ifs_cbrl(fd, CBRL_OP_UNLOCK, CBRL_LK_SH,
 430             plock->start, plock->size, false, 0, plock->context.smbpid,
 431             plock->context.tid, plock->fnum);
 432
 433         END_PROFILE(syscall_brl_unlock);
 434
 435         if (error) {
 436                 DEBUG(10, ("returning false.\n"));
 437                 return false;
 438         }
 439
 440         /* For symmetry purposes, end our oplock contention even though its
 441          * currently a no-op. */
 442         contend_level2_oplocks_end(br_lck->fsp, LEVEL2_CONTEND_WINDOWS_BRL);
 443
 444         DEBUG(10, ("returning true.\n"));
 445         return true;
 446
 447         /* Problem with storing things in TDB: I won't know what BRL to unlock in the TDB.
 448          *  - I could fake it?
 449          *  - I could send Samba a message with which lock is being unlocked?
 450          *  - I could *easily* make the "id" something you always pass in to
 451          *  lock, unlock or cancel -- it identifies a lock. Makes sense!
 452          */
 453 }
 454
 455 /* Default implementation only calls this on PENDING locks. */
 456 bool onefs_brl_cancel_windows(vfs_handle_struct *handle,
 457                               struct byte_range_lock *br_lck,
 458                               struct lock_struct *plock,
 459                               struct blocking_lock_record *blr)
 460 {
 461         int error;
 462         int fd = br_lck->fsp->fh->fd;
 463         struct onefs_cbrl_blr_state *bs;
 464
 465         START_PROFILE(syscall_brl_cancel);
 466
 467         SMB_ASSERT(plock);
 468         SMB_ASSERT(plock->lock_flav == WINDOWS_LOCK);
 469         SMB_ASSERT(blr);
 470
 471         onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");
 472
 473         bs = ((struct onefs_cbrl_blr_state *)blr->blr_private);
 474         SMB_ASSERT(bs);
 475
 476         if (bs->state == ONEFS_CBRL_DONE || bs->state == ONEFS_CBRL_ERROR) {
 477                 /* No-op. */
 478                 DEBUG(10, ("State=%d, returning true\n", bs->state));
 479                 END_PROFILE(syscall_brl_cancel);
 480                 return true;
 481         }
 482
 483         SMB_ASSERT(bs->state == ONEFS_CBRL_NONE ||
 484             bs->state == ONEFS_CBRL_ASYNC);
 485
 486         /* A real cancel. */
 487         DEBUG(10, ("Calling ifs_cbrl(CANCEL)...\n"));
 488         error = ifs_cbrl(fd, CBRL_OP_CANCEL, CBRL_LK_UNSPEC, plock->start,
 489             plock->size, false, bs->id, plock->context.smbpid,
 490             plock->context.tid, plock->fnum);
 491
 492         END_PROFILE(syscall_brl_cancel);
 493
 494         if (error) {
 495                 DEBUG(10, ("returning false\n"));
 496                 bs->state = ONEFS_CBRL_ERROR;
 497                 return false;
 498         }
 499
 500         bs->state = ONEFS_CBRL_DONE;
 501         onefs_cbrl_enumerate_blq("onefs_brl_cancel_windows");
 502         DEBUG(10, ("returning true\n"));
 503         return true;
 504 }
 505
 506 bool onefs_strict_lock(vfs_handle_struct *handle,
 507                         files_struct *fsp,
 508                         struct lock_struct *plock)
 509 {
 510         int error;
 511
 512         START_PROFILE(syscall_strict_lock);
 513
 514         SMB_ASSERT(plock->lock_type == READ_LOCK ||
 515             plock->lock_type == WRITE_LOCK);
 516
 517         if (!lp_locking(handle->conn->params) ||
 518             !lp_strict_locking(handle->conn->params)) {
 519                 END_PROFILE(syscall_strict_lock);
 520                 return True;
 521         }
 522
 523         if (plock->lock_flav == POSIX_LOCK) {
 524                 END_PROFILE(syscall_strict_lock);
 525                 return SMB_VFS_NEXT_STRICT_LOCK(handle, fsp, plock);
 526         }
 527
 528         if (plock->size == 0) {
 529                 END_PROFILE(syscall_strict_lock);
 530                 return True;
 531         }
 532
 533         error = ifs_cbrl(fsp->fh->fd, CBRL_OP_LOCK,
 534             plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
 535             plock->start, plock->size, 0, 0, plock->context.smbpid,
 536             plock->context.tid, plock->fnum);
 537
 538         END_PROFILE(syscall_strict_lock);
 539
 540         return (error == 0);
 541 }
 542
 543 void onefs_strict_unlock(vfs_handle_struct *handle,
 544                         files_struct *fsp,
 545                         struct lock_struct *plock)
 546 {
 547         START_PROFILE(syscall_strict_unlock);
 548
 549         SMB_ASSERT(plock->lock_type == READ_LOCK ||
 550             plock->lock_type == WRITE_LOCK);
 551
 552         if (!lp_locking(handle->conn->params) ||
 553             !lp_strict_locking(handle->conn->params)) {
 554                 END_PROFILE(syscall_strict_unlock);
 555                 return;
 556         }
 557
 558         if (plock->lock_flav == POSIX_LOCK) {
 559                 SMB_VFS_NEXT_STRICT_UNLOCK(handle, fsp, plock);
 560                 END_PROFILE(syscall_strict_unlock);
 561                 return;
 562         }
 563
 564         if (plock->size == 0) {
 565                 END_PROFILE(syscall_strict_unlock);
 566                 return;
 567         }
 568
 569         if (fsp->fh) {
 570                 ifs_cbrl(fsp->fh->fd, CBRL_OP_UNLOCK,
 571                     plock->lock_type == READ_LOCK ? CBRL_LK_RD : CBRL_LK_WR,
 572                     plock->start, plock->size, 0, 0, plock->context.smbpid,
 573                     plock->context.tid, plock->fnum);
 574         }
 575
 576         END_PROFILE(syscall_strict_unlock);
 577 }
 578
 579 /* TODO Optimization: Abstract out brl_get_locks() in the Windows case.
 580  * We'll malloc some memory or whatever (can't return NULL), but not actually
 581  * touch the TDB. */
 582
 583 /* XXX brl_locktest: CBRL does not support calling this, but its only for
 584  * strict locking. Add empty VOP? */
 585
 586 /* XXX brl_lockquery: CBRL does not support calling this for WINDOWS LOCKS, but
 587  * its only called for POSIX LOCKS. Add empty VOP? */
 588
 589 /* XXX brl_close_fnum: CBRL will do this automatically. I think this is a NO-OP
 590  * for us, we could add an empty VOP. */
 591