source3/smbd/oplock.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    oplock processing
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 1998 - 2001
   6    Copyright (C) Volker Lendecke 2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #define DBGC_CLASS DBGC_LOCKING
  23 #include "includes.h"
  24 #include "smbd/globals.h"
  25
  26 /****************************************************************************
  27  Get the number of current exclusive oplocks.
  28 ****************************************************************************/
  29
  30 int32 get_number_of_exclusive_open_oplocks(void)
  31 {
  32   return exclusive_oplocks_open;
  33 }
  34
  35 /*
  36  * helper function used by the kernel oplock backends to post the break message
  37  */
  38 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  39 {
  40         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  41
  42         /* Put the kernel break info into the message. */
  43         push_file_id_24((char *)msg, &fsp->file_id);
  44         SIVAL(msg,24,fsp->fh->gen_id);
  45
  46         /* Don't need to be root here as we're only ever
  47            sending to ourselves. */
  48
  49         messaging_send_buf(msg_ctx, procid_self(),
  50                            MSG_SMB_KERNEL_BREAK,
  51                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  52 }
  53
  54 /****************************************************************************
  55  Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
  56  disabled (just sets flags). Returns True if oplock set.
  57 ****************************************************************************/
  58
  59 bool set_file_oplock(files_struct *fsp, int oplock_type)
  60 {
  61         if ((fsp->oplock_type != NO_OPLOCK) &&
  62             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  63             koplocks &&
  64             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
  65                 return False;
  66         }
  67
  68         fsp->oplock_type = oplock_type;
  69         fsp->sent_oplock_break = NO_BREAK_SENT;
  70         if (oplock_type == LEVEL_II_OPLOCK) {
  71                 level_II_oplocks_open++;
  72         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  73                 exclusive_oplocks_open++;
  74         }
  75
  76         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  77                     "tv_sec = %x, tv_usec = %x\n",
  78                  fsp->fsp_name, file_id_string_tos(&fsp->file_id),
  79                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  80                  (int)fsp->open_time.tv_usec ));
  81
  82         return True;
  83 }
  84
  85 /****************************************************************************
  86  Attempt to release an oplock on a file. Decrements oplock count.
  87 ****************************************************************************/
  88
  89 void release_file_oplock(files_struct *fsp)
  90 {
  91         if ((fsp->oplock_type != NO_OPLOCK) &&
  92             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  93             koplocks) {
  94                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
  95         }
  96
  97         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  98                 level_II_oplocks_open--;
  99         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 100                 exclusive_oplocks_open--;
 101         }
 102
 103         SMB_ASSERT(exclusive_oplocks_open>=0);
 104         SMB_ASSERT(level_II_oplocks_open>=0);
 105
 106         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 107                 /* This doesn't matter for close. */
 108                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 109         } else {
 110                 fsp->oplock_type = NO_OPLOCK;
 111         }
 112         fsp->sent_oplock_break = NO_BREAK_SENT;
 113
 114         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 115
 116         TALLOC_FREE(fsp->oplock_timeout);
 117 }
 118
 119 /****************************************************************************
 120  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 121 ****************************************************************************/
 122
 123 static void downgrade_file_oplock(files_struct *fsp)
 124 {
 125         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 126                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 127                 return;
 128         }
 129
 130         if (koplocks) {
 131                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 132         }
 133         fsp->oplock_type = LEVEL_II_OPLOCK;
 134         exclusive_oplocks_open--;
 135         level_II_oplocks_open++;
 136         fsp->sent_oplock_break = NO_BREAK_SENT;
 137 }
 138
 139 /****************************************************************************
 140  Remove a file oplock. Copes with level II and exclusive.
 141  Locks then unlocks the share mode lock. Client can decide to go directly
 142  to none even if a "break-to-level II" was sent.
 143 ****************************************************************************/
 144
 145 bool remove_oplock(files_struct *fsp)
 146 {
 147         bool ret;
 148         struct share_mode_lock *lck;
 149
 150         /* Remove the oplock flag from the sharemode. */
 151         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 152                                   NULL);
 153         if (lck == NULL) {
 154                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 155                          "file %s\n", fsp->fsp_name ));
 156                 return False;
 157         }
 158         ret = remove_share_oplock(lck, fsp);
 159         if (!ret) {
 160                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 161                          "file %s fnum %d, %s\n",
 162                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 163         }
 164         release_file_oplock(fsp);
 165         TALLOC_FREE(lck);
 166         return ret;
 167 }
 168
 169 /*
 170  * Deal with a reply when a break-to-level II was sent.
 171  */
 172 bool downgrade_oplock(files_struct *fsp)
 173 {
 174         bool ret;
 175         struct share_mode_lock *lck;
 176
 177         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 178                                   NULL);
 179         if (lck == NULL) {
 180                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 181                          "file %s\n", fsp->fsp_name ));
 182                 return False;
 183         }
 184         ret = downgrade_share_oplock(lck, fsp);
 185         if (!ret) {
 186                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 187                          "for file %s fnum %d, file_id %s\n",
 188                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 189         }
 190
 191         downgrade_file_oplock(fsp);
 192         TALLOC_FREE(lck);
 193         return ret;
 194 }
 195
 196 /*
 197  * Some kernel oplock implementations handle the notification themselves.
 198  */
 199 bool should_notify_deferred_opens()
 200 {
 201         return !(koplocks &&
 202                 (koplocks->flags & KOPLOCKS_DEFERRED_OPEN_NOTIFICATION));
 203 }
 204
 205 /****************************************************************************
 206  Set up an oplock break message.
 207 ****************************************************************************/
 208
 209 static char *new_break_smb_message(TALLOC_CTX *mem_ctx,
 210                                    files_struct *fsp, uint8 cmd)
 211 {
 212         char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
 213
 214         if (result == NULL) {
 215                 DEBUG(0, ("talloc failed\n"));
 216                 return NULL;
 217         }
 218
 219         memset(result,'\0',smb_size);
 220         srv_set_message(result,8,0,true);
 221         SCVAL(result,smb_com,SMBlockingX);
 222         SSVAL(result,smb_tid,fsp->conn->cnum);
 223         SSVAL(result,smb_pid,0xFFFF);
 224         SSVAL(result,smb_uid,0);
 225         SSVAL(result,smb_mid,0xFFFF);
 226         SCVAL(result,smb_vwv0,0xFF);
 227         SSVAL(result,smb_vwv2,fsp->fnum);
 228         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 229         SCVAL(result,smb_vwv3+1,cmd);
 230         return result;
 231 }
 232
 233 /****************************************************************************
 234  Function to do the waiting before sending a local break.
 235 ****************************************************************************/
 236
 237 static void wait_before_sending_break(void)
 238 {
 239         long wait_time = (long)lp_oplock_break_wait_time();
 240
 241         if (wait_time) {
 242                 smb_msleep(wait_time);
 243         }
 244 }
 245
 246 /****************************************************************************
 247  Ensure that we have a valid oplock.
 248 ****************************************************************************/
 249
 250 static files_struct *initial_break_processing(struct file_id id, unsigned long file_id)
 251 {
 252         files_struct *fsp = NULL;
 253
 254         if( DEBUGLVL( 3 ) ) {
 255                 dbgtext( "initial_break_processing: called for %s/%u\n",
 256                          file_id_string_tos(&id), (int)file_id);
 257                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 258                         exclusive_oplocks_open, level_II_oplocks_open );
 259         }
 260
 261         /*
 262          * We need to search the file open table for the
 263          * entry containing this dev and inode, and ensure
 264          * we have an oplock on it.
 265          */
 266
 267         fsp = file_find_dif(id, file_id);
 268
 269         if(fsp == NULL) {
 270                 /* The file could have been closed in the meantime - return success. */
 271                 if( DEBUGLVL( 3 ) ) {
 272                         dbgtext( "initial_break_processing: cannot find open file with " );
 273                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 274                         dbgtext( "allowing break to succeed.\n" );
 275                 }
 276                 return NULL;
 277         }
 278
 279         /* Ensure we have an oplock on the file */
 280
 281         /*
 282          * There is a potential race condition in that an oplock could
 283          * have been broken due to another udp request, and yet there are
 284          * still oplock break messages being sent in the udp message
 285          * queue for this file. So return true if we don't have an oplock,
 286          * as we may have just freed it.
 287          */
 288
 289         if(fsp->oplock_type == NO_OPLOCK) {
 290                 if( DEBUGLVL( 3 ) ) {
 291                         dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
 292                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 293                                  file_id_string_tos(&id), fsp->fh->gen_id );
 294                         dbgtext( "Allowing break to succeed regardless.\n" );
 295                 }
 296                 return NULL;
 297         }
 298
 299         return fsp;
 300 }
 301
 302 static void oplock_timeout_handler(struct event_context *ctx,
 303                                    struct timed_event *te,
 304                                    struct timeval now,
 305                                    void *private_data)
 306 {
 307         files_struct *fsp = (files_struct *)private_data;
 308
 309         /* Remove the timed event handler. */
 310         TALLOC_FREE(fsp->oplock_timeout);
 311         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n", fsp->fsp_name));
 312         global_client_failed_oplock_break = True;
 313         remove_oplock(fsp);
 314         reply_to_oplock_break_requests(fsp);
 315 }
 316
 317 /*******************************************************************
 318  Add a timeout handler waiting for the client reply.
 319 *******************************************************************/
 320
 321 static void add_oplock_timeout_handler(files_struct *fsp)
 322 {
 323         /*
 324          * If kernel oplocks already notifies smbds when an oplock break times
 325          * out, just return.
 326          */
 327         if (koplocks &&
 328             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 329                 return;
 330         }
 331
 332         if (fsp->oplock_timeout != NULL) {
 333                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 334                           "around\n"));
 335         }
 336
 337         fsp->oplock_timeout =
 338                 event_add_timed(smbd_event_context(), NULL,
 339                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 340                                 oplock_timeout_handler, fsp);
 341
 342         if (fsp->oplock_timeout == NULL) {
 343                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 344         }
 345 }
 346
 347 /*******************************************************************
 348  This handles the case of a write triggering a break to none
 349  message on a level2 oplock.
 350  When we get this message we may be in any of three states :
 351  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 352  the client for LEVEL2.
 353 *******************************************************************/
 354
 355 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 356                                                       void *private_data,
 357                                                       uint32_t msg_type,
 358                                                       struct server_id src,
 359                                                       DATA_BLOB *data)
 360 {
 361         struct share_mode_entry msg;
 362         files_struct *fsp;
 363         char *break_msg;
 364
 365         if (data->data == NULL) {
 366                 DEBUG(0, ("Got NULL buffer\n"));
 367                 return;
 368         }
 369
 370         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 371                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 372                 return;
 373         }
 374
 375         /* De-linearize incoming message. */
 376         message_to_share_mode_entry(&msg, (char *)data->data);
 377
 378         DEBUG(10, ("Got oplock async level 2 break message from pid %d: %s/%lu\n",
 379                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 380
 381         fsp = initial_break_processing(msg.id, msg.share_file_id);
 382
 383         if (fsp == NULL) {
 384                 /* We hit a race here. Break messages are sent, and before we
 385                  * get to process this message, we have closed the file.
 386                  * No need to reply as this is an async message. */
 387                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 388                 return;
 389         }
 390
 391         if (fsp->oplock_type == NO_OPLOCK) {
 392                 /* We already got a "break to none" message and we've handled it.
 393                  * just ignore. */
 394                 DEBUG(3, ("process_oplock_async_level2_break_message: already broken to none, ignoring.\n"));
 395                 return;
 396         }
 397
 398         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 399                 /* Don't tell the client, just downgrade. */
 400                 DEBUG(3, ("process_oplock_async_level2_break_message: downgrading fake level 2 oplock.\n"));
 401                 remove_oplock(fsp);
 402                 return;
 403         }
 404
 405         /* Ensure we're really at level2 state. */
 406         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 407
 408         DEBUG(10,("process_oplock_async_level2_break_message: sending break to "
 409                 "none message for fid %d, file %s\n",
 410                 fsp->fnum,
 411                 fsp->fsp_name));
 412
 413         /* Now send a break to none message to our client. */
 414
 415         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 416         if (break_msg == NULL) {
 417                 exit_server("Could not talloc break_msg\n");
 418         }
 419
 420         /* Need to wait before sending a break message if we sent ourselves this message. */
 421         if (procid_to_pid(&src) == sys_getpid()) {
 422                 wait_before_sending_break();
 423         }
 424
 425         show_msg(break_msg);
 426         if (!srv_send_smb(smbd_server_fd(),
 427                         break_msg, false, 0,
 428                         IS_CONN_ENCRYPTED(fsp->conn),
 429                         NULL)) {
 430                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 431         }
 432
 433         TALLOC_FREE(break_msg);
 434
 435         /* Async level2 request, don't send a reply, just remove the oplock. */
 436         remove_oplock(fsp);
 437 }
 438
 439 /*******************************************************************
 440  This handles the generic oplock break message from another smbd.
 441 *******************************************************************/
 442
 443 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 444                                          void *private_data,
 445                                          uint32_t msg_type,
 446                                          struct server_id src,
 447                                          DATA_BLOB *data)
 448 {
 449         struct share_mode_entry msg;
 450         files_struct *fsp;
 451         char *break_msg;
 452         bool break_to_level2 = False;
 453
 454         if (data->data == NULL) {
 455                 DEBUG(0, ("Got NULL buffer\n"));
 456                 return;
 457         }
 458
 459         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 460                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 461                 return;
 462         }
 463
 464         /* De-linearize incoming message. */
 465         message_to_share_mode_entry(&msg, (char *)data->data);
 466
 467         DEBUG(10, ("Got oplock break message from pid %d: %s/%lu\n",
 468                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 469
 470         fsp = initial_break_processing(msg.id, msg.share_file_id);
 471
 472         if (fsp == NULL) {
 473                 /* a We hit race here. Break messages are sent, and before we
 474                  * get to process this message, we have closed the file. Reply
 475                  * with 'ok, oplock broken' */
 476                 DEBUG(3, ("Did not find fsp\n"));
 477
 478                 /* We just send the same message back. */
 479                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 480                                    (uint8 *)data->data,
 481                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 482                 return;
 483         }
 484
 485         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 486                 /* Remember we have to inform the requesting PID when the
 487                  * client replies */
 488                 msg.pid = src;
 489                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 490                              &fsp->pending_break_messages,
 491                              &fsp->num_pending_break_messages);
 492                 return;
 493         }
 494
 495         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 496             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 497                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 498                           file_id_string_tos(&fsp->file_id),
 499                           fsp->fsp_name));
 500                 /* We just send the same message back. */
 501                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 502                                    (uint8 *)data->data,
 503                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 504                 return;
 505         }
 506
 507         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 508             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 509             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 510             lp_level2_oplocks(SNUM(fsp->conn))) {
 511                 break_to_level2 = True;
 512         }
 513
 514         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 515                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 516         if (break_msg == NULL) {
 517                 exit_server("Could not talloc break_msg\n");
 518         }
 519
 520         /* Need to wait before sending a break message if we sent ourselves this message. */
 521         if (procid_to_pid(&src) == sys_getpid()) {
 522                 wait_before_sending_break();
 523         }
 524
 525         show_msg(break_msg);
 526         if (!srv_send_smb(smbd_server_fd(),
 527                         break_msg, false, 0,
 528                         IS_CONN_ENCRYPTED(fsp->conn),
 529                         NULL)) {
 530                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 531         }
 532
 533         TALLOC_FREE(break_msg);
 534
 535         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 536
 537         msg.pid = src;
 538         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 539                      &fsp->pending_break_messages,
 540                      &fsp->num_pending_break_messages);
 541
 542         add_oplock_timeout_handler(fsp);
 543 }
 544
 545 /*******************************************************************
 546  This handles the kernel oplock break message.
 547 *******************************************************************/
 548
 549 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 550                                         void *private_data,
 551                                         uint32_t msg_type,
 552                                         struct server_id src,
 553                                         DATA_BLOB *data)
 554 {
 555         struct file_id id;
 556         unsigned long file_id;
 557         files_struct *fsp;
 558         char *break_msg;
 559
 560         if (data->data == NULL) {
 561                 DEBUG(0, ("Got NULL buffer\n"));
 562                 return;
 563         }
 564
 565         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 566                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 567                 return;
 568         }
 569
 570         /* Pull the data from the message. */
 571         pull_file_id_24((char *)data->data, &id);
 572         file_id = (unsigned long)IVAL(data->data, 24);
 573
 574         DEBUG(10, ("Got kernel oplock break message from pid %d: %s/%u\n",
 575                    (int)procid_to_pid(&src), file_id_string_tos(&id),
 576                    (unsigned int)file_id));
 577
 578         fsp = initial_break_processing(id, file_id);
 579
 580         if (fsp == NULL) {
 581                 DEBUG(3, ("Got a kernel oplock break message for a file "
 582                           "I don't know about\n"));
 583                 return;
 584         }
 585
 586         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 587                 /* This is ok, kernel oplocks come in completely async */
 588                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 589                           "break reply\n"));
 590                 return;
 591         }
 592
 593         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 594         if (break_msg == NULL) {
 595                 exit_server("Could not talloc break_msg\n");
 596         }
 597
 598         show_msg(break_msg);
 599         if (!srv_send_smb(smbd_server_fd(),
 600                         break_msg, false, 0,
 601                         IS_CONN_ENCRYPTED(fsp->conn),
 602                         NULL)) {
 603                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 604         }
 605
 606         TALLOC_FREE(break_msg);
 607
 608         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 609
 610         add_oplock_timeout_handler(fsp);
 611 }
 612
 613 void reply_to_oplock_break_requests(files_struct *fsp)
 614 {
 615         int i;
 616
 617         /*
 618          * If kernel oplocks already notifies smbds when oplocks are
 619          * broken/removed, just return.
 620          */
 621         if (koplocks &&
 622             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 623                 return;
 624         }
 625
 626         for (i=0; i<fsp->num_pending_break_messages; i++) {
 627                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 628                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 629
 630                 share_mode_entry_to_message(msg, e);
 631
 632                 messaging_send_buf(smbd_messaging_context(), e->pid,
 633                                    MSG_SMB_BREAK_RESPONSE,
 634                                    (uint8 *)msg,
 635                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 636         }
 637
 638         SAFE_FREE(fsp->pending_break_messages);
 639         fsp->num_pending_break_messages = 0;
 640         if (fsp->oplock_timeout != NULL) {
 641                 /* Remove the timed event handler. */
 642                 TALLOC_FREE(fsp->oplock_timeout);
 643                 fsp->oplock_timeout = NULL;
 644         }
 645         return;
 646 }
 647
 648 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 649                                           void *private_data,
 650                                           uint32_t msg_type,
 651                                           struct server_id src,
 652                                           DATA_BLOB *data)
 653 {
 654         struct share_mode_entry msg;
 655
 656         if (data->data == NULL) {
 657                 DEBUG(0, ("Got NULL buffer\n"));
 658                 return;
 659         }
 660
 661         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 662                 DEBUG(0, ("Got invalid msg len %u\n",
 663                           (unsigned int)data->length));
 664                 return;
 665         }
 666
 667         /* De-linearize incoming message. */
 668         message_to_share_mode_entry(&msg, (char *)data->data);
 669
 670         DEBUG(10, ("Got oplock break response from pid %d: %s/%lu mid %u\n",
 671                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id,
 672                    (unsigned int)msg.op_mid));
 673
 674         /* Here's the hack from open.c, store the mid in the 'port' field */
 675         schedule_deferred_open_smb_message(msg.op_mid);
 676 }
 677
 678 static void process_open_retry_message(struct messaging_context *msg_ctx,
 679                                        void *private_data,
 680                                        uint32_t msg_type,
 681                                        struct server_id src,
 682                                        DATA_BLOB *data)
 683 {
 684         struct share_mode_entry msg;
 685
 686         if (data->data == NULL) {
 687                 DEBUG(0, ("Got NULL buffer\n"));
 688                 return;
 689         }
 690
 691         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 692                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 693                 return;
 694         }
 695
 696         /* De-linearize incoming message. */
 697         message_to_share_mode_entry(&msg, (char *)data->data);
 698
 699         DEBUG(10, ("Got open retry msg from pid %d: %s mid %u\n",
 700                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id),
 701                    (unsigned int)msg.op_mid));
 702
 703         schedule_deferred_open_smb_message(msg.op_mid);
 704 }
 705
 706 /****************************************************************************
 707  This function is called on any file modification or lock request. If a file
 708  is level 2 oplocked then it must tell all other level 2 holders to break to
 709  none.
 710 ****************************************************************************/
 711
 712 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 713                                               enum level2_contention_type type)
 714 {
 715         int i;
 716         struct share_mode_lock *lck;
 717
 718         /*
 719          * If this file is level II oplocked then we need
 720          * to grab the shared memory lock and inform all
 721          * other files with a level II lock that they need
 722          * to flush their read caches. We keep the lock over
 723          * the shared memory area whilst doing this.
 724          */
 725
 726         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 727                 return;
 728
 729         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 730                                   NULL);
 731         if (lck == NULL) {
 732                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 733                          "share mode entry for file %s.\n", fsp->fsp_name ));
 734                 return;
 735         }
 736
 737         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 738                   lck->num_share_modes ));
 739
 740         for(i = 0; i < lck->num_share_modes; i++) {
 741                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 742                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 743
 744                 if (!is_valid_share_mode_entry(share_entry)) {
 745                         continue;
 746                 }
 747
 748                 /*
 749                  * As there could have been multiple writes waiting at the
 750                  * lock_share_entry gate we may not be the first to
 751                  * enter. Hence the state of the op_types in the share mode
 752                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 753                  * oplock. It will do no harm to re-send break messages to
 754                  * those smbd's that are still waiting their turn to remove
 755                  * their LEVEL_II state, and also no harm to ignore existing
 756                  * NO_OPLOCK states. JRA.
 757                  */
 758
 759                 DEBUG(10,("release_level_2_oplocks_on_change: "
 760                           "share_entry[%i]->op_type == %d\n",
 761                           i, share_entry->op_type ));
 762
 763                 if (share_entry->op_type == NO_OPLOCK) {
 764                         continue;
 765                 }
 766
 767                 /* Paranoia .... */
 768                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 769                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 770                                  "share mode entry %d is an exlusive "
 771                                  "oplock !\n", i ));
 772                         TALLOC_FREE(lck);
 773                         abort();
 774                 }
 775
 776                 share_mode_entry_to_message(msg, share_entry);
 777
 778                 /*
 779                  * Deal with a race condition when breaking level2
 780                  * oplocks. Don't send all the messages and release
 781                  * the lock, this allows someone else to come in and
 782                  * get a level2 lock before any of the messages are
 783                  * processed, and thus miss getting a break message.
 784                  * Ensure at least one entry (the one we're breaking)
 785                  * is processed immediately under the lock and becomes
 786                  * set as NO_OPLOCK to stop any waiter getting a level2.
 787                  * Bugid #5980.
 788                  */
 789
 790                 if (procid_is_me(&share_entry->pid)) {
 791                         DATA_BLOB blob = data_blob_const(msg,
 792                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 793                         process_oplock_async_level2_break_message(smbd_messaging_context(),
 794                                                 NULL,
 795                                                 MSG_SMB_ASYNC_LEVEL2_BREAK,
 796                                                 share_entry->pid,
 797                                                 &blob);
 798                 } else {
 799                         messaging_send_buf(smbd_messaging_context(),
 800                                         share_entry->pid,
 801                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 802                                         (uint8 *)msg,
 803                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 804                 }
 805         }
 806
 807         /* We let the message receivers handle removing the oplock state
 808            in the share mode lock db. */
 809
 810         TALLOC_FREE(lck);
 811 }
 812
 813 void contend_level2_oplocks_begin(files_struct *fsp,
 814                                   enum level2_contention_type type)
 815 {
 816         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 817                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 818                 return;
 819         }
 820
 821         contend_level2_oplocks_begin_default(fsp, type);
 822 }
 823
 824 void contend_level2_oplocks_end(files_struct *fsp,
 825                                 enum level2_contention_type type)
 826 {
 827         /* Only kernel oplocks implement this so far */
 828         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 829                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 830         }
 831 }
 832
 833 /****************************************************************************
 834  Linearize a share mode entry struct to an internal oplock break message.
 835 ****************************************************************************/
 836
 837 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 838 {
 839         SIVAL(msg,0,(uint32)e->pid.pid);
 840         SSVAL(msg,4,e->op_mid);
 841         SSVAL(msg,6,e->op_type);
 842         SIVAL(msg,8,e->access_mask);
 843         SIVAL(msg,12,e->share_access);
 844         SIVAL(msg,16,e->private_options);
 845         SIVAL(msg,20,(uint32)e->time.tv_sec);
 846         SIVAL(msg,24,(uint32)e->time.tv_usec);
 847         push_file_id_24(msg+28, &e->id);
 848         SIVAL(msg,52,e->share_file_id);
 849         SIVAL(msg,56,e->uid);
 850         SSVAL(msg,60,e->flags);
 851 #ifdef CLUSTER_SUPPORT
 852         SIVAL(msg,62,e->pid.vnn);
 853 #endif
 854 }
 855
 856 /****************************************************************************
 857  De-linearize an internal oplock break message to a share mode entry struct.
 858 ****************************************************************************/
 859
 860 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 861 {
 862         e->pid.pid = (pid_t)IVAL(msg,0);
 863         e->op_mid = SVAL(msg,4);
 864         e->op_type = SVAL(msg,6);
 865         e->access_mask = IVAL(msg,8);
 866         e->share_access = IVAL(msg,12);
 867         e->private_options = IVAL(msg,16);
 868         e->time.tv_sec = (time_t)IVAL(msg,20);
 869         e->time.tv_usec = (int)IVAL(msg,24);
 870         pull_file_id_24(msg+28, &e->id);
 871         e->share_file_id = (unsigned long)IVAL(msg,52);
 872         e->uid = (uint32)IVAL(msg,56);
 873         e->flags = (uint16)SVAL(msg,60);
 874 #ifdef CLUSTER_SUPPORT
 875         e->pid.vnn = IVAL(msg,62);
 876 #endif
 877 }
 878
 879 /****************************************************************************
 880  Setup oplocks for this process.
 881 ****************************************************************************/
 882
 883 bool init_oplocks(struct messaging_context *msg_ctx)
 884 {
 885         DEBUG(3,("init_oplocks: initializing messages.\n"));
 886
 887         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 888                            process_oplock_break_message);
 889         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 890                            process_oplock_async_level2_break_message);
 891         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 892                            process_oplock_break_response);
 893         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 894                            process_kernel_oplock_break);
 895         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 896                            process_open_retry_message);
 897
 898         if (lp_kernel_oplocks()) {
 899 #if HAVE_KERNEL_OPLOCKS_IRIX
 900                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 901 #elif HAVE_KERNEL_OPLOCKS_LINUX
 902                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 903 #elif HAVE_ONEFS
 904                 koplocks = onefs_init_kernel_oplocks(talloc_autofree_context());
 905 #endif
 906         }
 907
 908         return True;
 909 }