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 void break_level2_to_none_async(files_struct *fsp)
 348 {
 349         char *break_msg;
 350
 351         if (fsp->oplock_type == NO_OPLOCK) {
 352                 /* We already got a "break to none" message and we've handled
 353                  * it.  just ignore. */
 354                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 355                           "broken to none, ignoring.\n"));
 356                 return;
 357         }
 358
 359         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 360                 /* Don't tell the client, just downgrade. */
 361                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 362                           "downgrading fake level 2 oplock.\n"));
 363                 remove_oplock(fsp);
 364                 return;
 365         }
 366
 367         /* Ensure we're really at level2 state. */
 368         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 369
 370         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 371                   "to none message for fid %d, file %s\n", fsp->fnum,
 372                   fsp->fsp_name));
 373
 374         /* Now send a break to none message to our client. */
 375         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 376         if (break_msg == NULL) {
 377                 exit_server("Could not talloc break_msg\n");
 378         }
 379
 380         show_msg(break_msg);
 381         if (!srv_send_smb(smbd_server_fd(),
 382                         break_msg, false, 0,
 383                         IS_CONN_ENCRYPTED(fsp->conn),
 384                         NULL)) {
 385                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 386         }
 387
 388         TALLOC_FREE(break_msg);
 389
 390         /* Async level2 request, don't send a reply, just remove the oplock. */
 391         remove_oplock(fsp);
 392
 393 }
 394
 395 /*******************************************************************
 396  This handles the case of a write triggering a break to none
 397  message on a level2 oplock.
 398  When we get this message we may be in any of three states :
 399  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 400  the client for LEVEL2.
 401 *******************************************************************/
 402
 403 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 404                                                       void *private_data,
 405                                                       uint32_t msg_type,
 406                                                       struct server_id src,
 407                                                       DATA_BLOB *data)
 408 {
 409         struct share_mode_entry msg;
 410         files_struct *fsp;
 411
 412         if (data->data == NULL) {
 413                 DEBUG(0, ("Got NULL buffer\n"));
 414                 return;
 415         }
 416
 417         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 418                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 419                 return;
 420         }
 421
 422         /* De-linearize incoming message. */
 423         message_to_share_mode_entry(&msg, (char *)data->data);
 424
 425         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 426                    "%s/%lu\n", procid_str(debug_ctx(), &src),
 427                    file_id_string_tos(&msg.id), msg.share_file_id));
 428
 429         fsp = initial_break_processing(msg.id, msg.share_file_id);
 430
 431         if (fsp == NULL) {
 432                 /* We hit a race here. Break messages are sent, and before we
 433                  * get to process this message, we have closed the file.
 434                  * No need to reply as this is an async message. */
 435                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 436                 return;
 437         }
 438
 439         break_level2_to_none_async(fsp);
 440 }
 441
 442 /*******************************************************************
 443  This handles the generic oplock break message from another smbd.
 444 *******************************************************************/
 445
 446 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 447                                          void *private_data,
 448                                          uint32_t msg_type,
 449                                          struct server_id src,
 450                                          DATA_BLOB *data)
 451 {
 452         struct share_mode_entry msg;
 453         files_struct *fsp;
 454         char *break_msg;
 455         bool break_to_level2 = False;
 456
 457         if (data->data == NULL) {
 458                 DEBUG(0, ("Got NULL buffer\n"));
 459                 return;
 460         }
 461
 462         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 463                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 464                 return;
 465         }
 466
 467         /* De-linearize incoming message. */
 468         message_to_share_mode_entry(&msg, (char *)data->data);
 469
 470         DEBUG(10, ("Got oplock break message from pid %s: %s/%lu\n",
 471                    procid_str(debug_ctx(), &src), file_id_string_tos(&msg.id),
 472                    msg.share_file_id));
 473
 474         fsp = initial_break_processing(msg.id, msg.share_file_id);
 475
 476         if (fsp == NULL) {
 477                 /* a We hit race here. Break messages are sent, and before we
 478                  * get to process this message, we have closed the file. Reply
 479                  * with 'ok, oplock broken' */
 480                 DEBUG(3, ("Did not find fsp\n"));
 481
 482                 /* We just send the same message back. */
 483                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 484                                    (uint8 *)data->data,
 485                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 486                 return;
 487         }
 488
 489         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 490                 /* Remember we have to inform the requesting PID when the
 491                  * client replies */
 492                 msg.pid = src;
 493                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 494                              &fsp->pending_break_messages,
 495                              &fsp->num_pending_break_messages);
 496                 return;
 497         }
 498
 499         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 500             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 501                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 502                           file_id_string_tos(&fsp->file_id),
 503                           fsp->fsp_name));
 504                 /* We just send the same message back. */
 505                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 506                                    (uint8 *)data->data,
 507                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 508                 return;
 509         }
 510
 511         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 512             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 513             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 514             lp_level2_oplocks(SNUM(fsp->conn))) {
 515                 break_to_level2 = True;
 516         }
 517
 518         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 519                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 520         if (break_msg == NULL) {
 521                 exit_server("Could not talloc break_msg\n");
 522         }
 523
 524         /* Need to wait before sending a break message if we sent ourselves this message. */
 525         if (procid_is_me(&src)) {
 526                 wait_before_sending_break();
 527         }
 528
 529         show_msg(break_msg);
 530         if (!srv_send_smb(smbd_server_fd(),
 531                         break_msg, false, 0,
 532                         IS_CONN_ENCRYPTED(fsp->conn),
 533                         NULL)) {
 534                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 535         }
 536
 537         TALLOC_FREE(break_msg);
 538
 539         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 540
 541         msg.pid = src;
 542         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 543                      &fsp->pending_break_messages,
 544                      &fsp->num_pending_break_messages);
 545
 546         add_oplock_timeout_handler(fsp);
 547 }
 548
 549 /*******************************************************************
 550  This handles the kernel oplock break message.
 551 *******************************************************************/
 552
 553 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 554                                         void *private_data,
 555                                         uint32_t msg_type,
 556                                         struct server_id src,
 557                                         DATA_BLOB *data)
 558 {
 559         struct file_id id;
 560         unsigned long file_id;
 561         files_struct *fsp;
 562         char *break_msg;
 563
 564         if (data->data == NULL) {
 565                 DEBUG(0, ("Got NULL buffer\n"));
 566                 return;
 567         }
 568
 569         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 570                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 571                 return;
 572         }
 573
 574         /* Pull the data from the message. */
 575         pull_file_id_24((char *)data->data, &id);
 576         file_id = (unsigned long)IVAL(data->data, 24);
 577
 578         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 579                    procid_str(debug_ctx(), &src), file_id_string_tos(&id),
 580                    (unsigned int)file_id));
 581
 582         fsp = initial_break_processing(id, file_id);
 583
 584         if (fsp == NULL) {
 585                 DEBUG(3, ("Got a kernel oplock break message for a file "
 586                           "I don't know about\n"));
 587                 return;
 588         }
 589
 590         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 591                 /* This is ok, kernel oplocks come in completely async */
 592                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 593                           "break reply\n"));
 594                 return;
 595         }
 596
 597         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 598         if (break_msg == NULL) {
 599                 exit_server("Could not talloc break_msg\n");
 600         }
 601
 602         show_msg(break_msg);
 603         if (!srv_send_smb(smbd_server_fd(),
 604                         break_msg, false, 0,
 605                         IS_CONN_ENCRYPTED(fsp->conn),
 606                         NULL)) {
 607                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 608         }
 609
 610         TALLOC_FREE(break_msg);
 611
 612         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 613
 614         add_oplock_timeout_handler(fsp);
 615 }
 616
 617 void reply_to_oplock_break_requests(files_struct *fsp)
 618 {
 619         int i;
 620
 621         /*
 622          * If kernel oplocks already notifies smbds when oplocks are
 623          * broken/removed, just return.
 624          */
 625         if (koplocks &&
 626             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 627                 return;
 628         }
 629
 630         for (i=0; i<fsp->num_pending_break_messages; i++) {
 631                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 632                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 633
 634                 share_mode_entry_to_message(msg, e);
 635
 636                 messaging_send_buf(smbd_messaging_context(), e->pid,
 637                                    MSG_SMB_BREAK_RESPONSE,
 638                                    (uint8 *)msg,
 639                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 640         }
 641
 642         SAFE_FREE(fsp->pending_break_messages);
 643         fsp->num_pending_break_messages = 0;
 644         if (fsp->oplock_timeout != NULL) {
 645                 /* Remove the timed event handler. */
 646                 TALLOC_FREE(fsp->oplock_timeout);
 647                 fsp->oplock_timeout = NULL;
 648         }
 649         return;
 650 }
 651
 652 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 653                                           void *private_data,
 654                                           uint32_t msg_type,
 655                                           struct server_id src,
 656                                           DATA_BLOB *data)
 657 {
 658         struct share_mode_entry msg;
 659
 660         if (data->data == NULL) {
 661                 DEBUG(0, ("Got NULL buffer\n"));
 662                 return;
 663         }
 664
 665         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 666                 DEBUG(0, ("Got invalid msg len %u\n",
 667                           (unsigned int)data->length));
 668                 return;
 669         }
 670
 671         /* De-linearize incoming message. */
 672         message_to_share_mode_entry(&msg, (char *)data->data);
 673
 674         DEBUG(10, ("Got oplock break response from pid %s: %s/%lu mid %u\n",
 675                    procid_str(debug_ctx(), &src), file_id_string_tos(&msg.id),
 676                    msg.share_file_id, (unsigned int)msg.op_mid));
 677
 678         /* Here's the hack from open.c, store the mid in the 'port' field */
 679         schedule_deferred_open_smb_message(msg.op_mid);
 680 }
 681
 682 static void process_open_retry_message(struct messaging_context *msg_ctx,
 683                                        void *private_data,
 684                                        uint32_t msg_type,
 685                                        struct server_id src,
 686                                        DATA_BLOB *data)
 687 {
 688         struct share_mode_entry msg;
 689
 690         if (data->data == NULL) {
 691                 DEBUG(0, ("Got NULL buffer\n"));
 692                 return;
 693         }
 694
 695         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 696                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 697                 return;
 698         }
 699
 700         /* De-linearize incoming message. */
 701         message_to_share_mode_entry(&msg, (char *)data->data);
 702
 703         DEBUG(10, ("Got open retry msg from pid %s: %s mid %u\n",
 704                    procid_str(debug_ctx(), &src), file_id_string_tos(&msg.id),
 705                    (unsigned int)msg.op_mid));
 706
 707         schedule_deferred_open_smb_message(msg.op_mid);
 708 }
 709
 710 /****************************************************************************
 711  This function is called on any file modification or lock request. If a file
 712  is level 2 oplocked then it must tell all other level 2 holders to break to
 713  none.
 714 ****************************************************************************/
 715
 716 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 717                                               enum level2_contention_type type)
 718 {
 719         int i;
 720         struct share_mode_lock *lck;
 721
 722         /*
 723          * If this file is level II oplocked then we need
 724          * to grab the shared memory lock and inform all
 725          * other files with a level II lock that they need
 726          * to flush their read caches. We keep the lock over
 727          * the shared memory area whilst doing this.
 728          */
 729
 730         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 731                 return;
 732
 733         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 734                                   NULL);
 735         if (lck == NULL) {
 736                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 737                          "share mode entry for file %s.\n", fsp->fsp_name ));
 738                 return;
 739         }
 740
 741         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 742                   lck->num_share_modes ));
 743
 744         for(i = 0; i < lck->num_share_modes; i++) {
 745                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 746                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 747
 748                 if (!is_valid_share_mode_entry(share_entry)) {
 749                         continue;
 750                 }
 751
 752                 /*
 753                  * As there could have been multiple writes waiting at the
 754                  * lock_share_entry gate we may not be the first to
 755                  * enter. Hence the state of the op_types in the share mode
 756                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 757                  * oplock. It will do no harm to re-send break messages to
 758                  * those smbd's that are still waiting their turn to remove
 759                  * their LEVEL_II state, and also no harm to ignore existing
 760                  * NO_OPLOCK states. JRA.
 761                  */
 762
 763                 DEBUG(10,("release_level_2_oplocks_on_change: "
 764                           "share_entry[%i]->op_type == %d\n",
 765                           i, share_entry->op_type ));
 766
 767                 if (share_entry->op_type == NO_OPLOCK) {
 768                         continue;
 769                 }
 770
 771                 /* Paranoia .... */
 772                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 773                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 774                                  "share mode entry %d is an exlusive "
 775                                  "oplock !\n", i ));
 776                         TALLOC_FREE(lck);
 777                         abort();
 778                 }
 779
 780                 share_mode_entry_to_message(msg, share_entry);
 781
 782                 /*
 783                  * Deal with a race condition when breaking level2
 784                  * oplocks. Don't send all the messages and release
 785                  * the lock, this allows someone else to come in and
 786                  * get a level2 lock before any of the messages are
 787                  * processed, and thus miss getting a break message.
 788                  * Ensure at least one entry (the one we're breaking)
 789                  * is processed immediately under the lock and becomes
 790                  * set as NO_OPLOCK to stop any waiter getting a level2.
 791                  * Bugid #5980.
 792                  */
 793
 794                 if (procid_is_me(&share_entry->pid)) {
 795                         wait_before_sending_break();
 796                         break_level2_to_none_async(fsp);
 797                 } else {
 798                         messaging_send_buf(smbd_messaging_context(),
 799                                         share_entry->pid,
 800                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 801                                         (uint8 *)msg,
 802                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 803                 }
 804         }
 805
 806         /* We let the message receivers handle removing the oplock state
 807            in the share mode lock db. */
 808
 809         TALLOC_FREE(lck);
 810 }
 811
 812 void contend_level2_oplocks_begin(files_struct *fsp,
 813                                   enum level2_contention_type type)
 814 {
 815         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 816                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 817                 return;
 818         }
 819
 820         contend_level2_oplocks_begin_default(fsp, type);
 821 }
 822
 823 void contend_level2_oplocks_end(files_struct *fsp,
 824                                 enum level2_contention_type type)
 825 {
 826         /* Only kernel oplocks implement this so far */
 827         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 828                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 829         }
 830 }
 831
 832 /****************************************************************************
 833  Linearize a share mode entry struct to an internal oplock break message.
 834 ****************************************************************************/
 835
 836 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 837 {
 838         SIVAL(msg,0,(uint32)e->pid.pid);
 839         SSVAL(msg,4,e->op_mid);
 840         SSVAL(msg,6,e->op_type);
 841         SIVAL(msg,8,e->access_mask);
 842         SIVAL(msg,12,e->share_access);
 843         SIVAL(msg,16,e->private_options);
 844         SIVAL(msg,20,(uint32)e->time.tv_sec);
 845         SIVAL(msg,24,(uint32)e->time.tv_usec);
 846         push_file_id_24(msg+28, &e->id);
 847         SIVAL(msg,52,e->share_file_id);
 848         SIVAL(msg,56,e->uid);
 849         SSVAL(msg,60,e->flags);
 850 #ifdef CLUSTER_SUPPORT
 851         SIVAL(msg,62,e->pid.vnn);
 852 #endif
 853 }
 854
 855 /****************************************************************************
 856  De-linearize an internal oplock break message to a share mode entry struct.
 857 ****************************************************************************/
 858
 859 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 860 {
 861         e->pid.pid = (pid_t)IVAL(msg,0);
 862         e->op_mid = SVAL(msg,4);
 863         e->op_type = SVAL(msg,6);
 864         e->access_mask = IVAL(msg,8);
 865         e->share_access = IVAL(msg,12);
 866         e->private_options = IVAL(msg,16);
 867         e->time.tv_sec = (time_t)IVAL(msg,20);
 868         e->time.tv_usec = (int)IVAL(msg,24);
 869         pull_file_id_24(msg+28, &e->id);
 870         e->share_file_id = (unsigned long)IVAL(msg,52);
 871         e->uid = (uint32)IVAL(msg,56);
 872         e->flags = (uint16)SVAL(msg,60);
 873 #ifdef CLUSTER_SUPPORT
 874         e->pid.vnn = IVAL(msg,62);
 875 #endif
 876 }
 877
 878 /****************************************************************************
 879  Setup oplocks for this process.
 880 ****************************************************************************/
 881
 882 bool init_oplocks(struct messaging_context *msg_ctx)
 883 {
 884         DEBUG(3,("init_oplocks: initializing messages.\n"));
 885
 886         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 887                            process_oplock_break_message);
 888         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 889                            process_oplock_async_level2_break_message);
 890         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 891                            process_oplock_break_response);
 892         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 893                            process_kernel_oplock_break);
 894         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 895                            process_open_retry_message);
 896
 897         if (lp_kernel_oplocks()) {
 898 #if HAVE_KERNEL_OPLOCKS_IRIX
 899                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 900 #elif HAVE_KERNEL_OPLOCKS_LINUX
 901                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 902 #elif HAVE_ONEFS
 903                 koplocks = onefs_init_kernel_oplocks(talloc_autofree_context());
 904 #endif
 905         }
 906
 907         return True;
 908 }