source/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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #define DBGC_CLASS DBGC_LOCKING
  24 #include "includes.h"
  25
  26 /* Current number of oplocks we have outstanding. */
  27 static int32 exclusive_oplocks_open = 0;
  28 static int32 level_II_oplocks_open = 0;
  29 BOOL global_client_failed_oplock_break = False;
  30
  31 extern uint32 global_client_caps;
  32 extern int smb_read_error;
  33
  34 static struct kernel_oplocks *koplocks;
  35
  36 /****************************************************************************
  37  Get the number of current exclusive oplocks.
  38 ****************************************************************************/
  39
  40 int32 get_number_of_exclusive_open_oplocks(void)
  41 {
  42   return exclusive_oplocks_open;
  43 }
  44
  45 /****************************************************************************
  46  Return True if an oplock message is pending.
  47 ****************************************************************************/
  48
  49 BOOL oplock_message_waiting(fd_set *fds)
  50 {
  51         if (koplocks && koplocks->msg_waiting(fds)) {
  52                 return True;
  53         }
  54
  55         return False;
  56 }
  57
  58 /****************************************************************************
  59  Find out if there are any kernel oplock messages waiting and process them
  60  if so. pfds is the fd_set from the main select loop (which contains any
  61  kernel oplock fd if that's what the system uses (IRIX). If may be NULL if
  62  we're calling this in a shutting down state.
  63 ****************************************************************************/
  64
  65 void process_kernel_oplocks(fd_set *pfds)
  66 {
  67         /*
  68          * We need to check for kernel oplocks before going into the select
  69          * here, as the EINTR generated by the linux kernel oplock may have
  70          * already been eaten. JRA.
  71          */
  72
  73         if (!koplocks) {
  74                 return;
  75         }
  76
  77         while (koplocks->msg_waiting(pfds)) {
  78                 files_struct *fsp;
  79                 char msg[MSG_SMB_KERNEL_BREAK_SIZE];
  80
  81                 fsp = koplocks->receive_message(pfds);
  82
  83                 if (fsp == NULL) {
  84                         DEBUG(3, ("Kernel oplock message announced, but none "
  85                                   "received\n"));
  86                         return;
  87                 }
  88
  89                 /* Put the kernel break info into the message. */
  90                 SDEV_T_VAL(msg,0,fsp->dev);
  91                 SINO_T_VAL(msg,8,fsp->inode);
  92                 SIVAL(msg,16,fsp->fh->file_id);
  93
  94                 /* Don't need to be root here as we're only ever
  95                    sending to ourselves. */
  96
  97                 message_send_pid(pid_to_procid(sys_getpid()),
  98                                  MSG_SMB_KERNEL_BREAK,
  99                                  &msg, MSG_SMB_KERNEL_BREAK_SIZE, True);
 100         }
 101 }
 102
 103 /****************************************************************************
 104  Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
 105  disabled (just sets flags). Returns True if oplock set.
 106 ****************************************************************************/
 107
 108 BOOL set_file_oplock(files_struct *fsp, int oplock_type)
 109 {
 110         if (koplocks && !koplocks->set_oplock(fsp, oplock_type)) {
 111                 return False;
 112         }
 113
 114         fsp->oplock_type = oplock_type;
 115         fsp->sent_oplock_break = NO_BREAK_SENT;
 116         if (oplock_type == LEVEL_II_OPLOCK) {
 117                 level_II_oplocks_open++;
 118         } else {
 119                 exclusive_oplocks_open++;
 120         }
 121
 122         DEBUG(5,("set_file_oplock: granted oplock on file %s, 0x%x/%.0f/%lu, "
 123                     "tv_sec = %x, tv_usec = %x\n",
 124                  fsp->fsp_name, (unsigned int)fsp->dev, (double)fsp->inode,
 125                  fsp->fh->file_id, (int)fsp->open_time.tv_sec,
 126                  (int)fsp->open_time.tv_usec ));
 127
 128         return True;
 129 }
 130
 131 /****************************************************************************
 132  Attempt to release an oplock on a file. Decrements oplock count.
 133 ****************************************************************************/
 134
 135 void release_file_oplock(files_struct *fsp)
 136 {
 137         if ((fsp->oplock_type != NO_OPLOCK) &&
 138             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 139             koplocks) {
 140                 koplocks->release_oplock(fsp);
 141         }
 142
 143         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 144                 level_II_oplocks_open--;
 145         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 146                 exclusive_oplocks_open--;
 147         }
 148
 149         SMB_ASSERT(exclusive_oplocks_open>=0);
 150         SMB_ASSERT(level_II_oplocks_open>=0);
 151
 152         fsp->oplock_type = NO_OPLOCK;
 153         fsp->sent_oplock_break = NO_BREAK_SENT;
 154
 155         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 156
 157         TALLOC_FREE(fsp->oplock_timeout);
 158 }
 159
 160 /****************************************************************************
 161  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 162 ****************************************************************************/
 163
 164 static void downgrade_file_oplock(files_struct *fsp)
 165 {
 166         if (koplocks) {
 167                 koplocks->release_oplock(fsp);
 168         }
 169         fsp->oplock_type = LEVEL_II_OPLOCK;
 170         exclusive_oplocks_open--;
 171         level_II_oplocks_open++;
 172         fsp->sent_oplock_break = NO_BREAK_SENT;
 173 }
 174
 175 /****************************************************************************
 176  Remove a file oplock. Copes with level II and exclusive.
 177  Locks then unlocks the share mode lock. Client can decide to go directly
 178  to none even if a "break-to-level II" was sent.
 179 ****************************************************************************/
 180
 181 BOOL remove_oplock(files_struct *fsp)
 182 {
 183         SMB_DEV_T dev = fsp->dev;
 184         SMB_INO_T inode = fsp->inode;
 185         BOOL ret;
 186         struct share_mode_lock *lck;
 187
 188         /* Remove the oplock flag from the sharemode. */
 189         lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
 190         if (lck == NULL) {
 191                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 192                          "file %s\n", fsp->fsp_name ));
 193                 return False;
 194         }
 195         ret = remove_share_oplock(lck, fsp);
 196         if (!ret) {
 197                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 198                          "file %s fnum %d, 0x%x/%.0f\n",
 199                          fsp->fsp_name, fsp->fnum, (unsigned int)dev,
 200                          (double)inode));
 201         }
 202         release_file_oplock(fsp);
 203         TALLOC_FREE(lck);
 204         return ret;
 205 }
 206
 207 /*
 208  * Deal with a reply when a break-to-level II was sent.
 209  */
 210 BOOL downgrade_oplock(files_struct *fsp)
 211 {
 212         SMB_DEV_T dev = fsp->dev;
 213         SMB_INO_T inode = fsp->inode;
 214         BOOL ret;
 215         struct share_mode_lock *lck;
 216
 217         lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
 218         if (lck == NULL) {
 219                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 220                          "file %s\n", fsp->fsp_name ));
 221                 return False;
 222         }
 223         ret = downgrade_share_oplock(lck, fsp);
 224         if (!ret) {
 225                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 226                          "for file %s fnum %d, dev = %x, inode = %.0f\n",
 227                          fsp->fsp_name, fsp->fnum, (unsigned int)dev,
 228                          (double)inode));
 229         }
 230
 231         downgrade_file_oplock(fsp);
 232         TALLOC_FREE(lck);
 233         return ret;
 234 }
 235
 236 /****************************************************************************
 237  Return the fd (if any) used for receiving oplock notifications.
 238 ****************************************************************************/
 239
 240 int oplock_notify_fd(void)
 241 {
 242         if (koplocks) {
 243                 return koplocks->notification_fd;
 244         }
 245
 246         return -1;
 247 }
 248
 249 /****************************************************************************
 250  Set up an oplock break message.
 251 ****************************************************************************/
 252
 253 static char *new_break_smb_message(TALLOC_CTX *mem_ctx,
 254                                    files_struct *fsp, uint8 cmd)
 255 {
 256         char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
 257
 258         if (result == NULL) {
 259                 DEBUG(0, ("talloc failed\n"));
 260                 return NULL;
 261         }
 262
 263         memset(result,'\0',smb_size);
 264         set_message(result,8,0,True);
 265         SCVAL(result,smb_com,SMBlockingX);
 266         SSVAL(result,smb_tid,fsp->conn->cnum);
 267         SSVAL(result,smb_pid,0xFFFF);
 268         SSVAL(result,smb_uid,0);
 269         SSVAL(result,smb_mid,0xFFFF);
 270         SCVAL(result,smb_vwv0,0xFF);
 271         SSVAL(result,smb_vwv2,fsp->fnum);
 272         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 273         SCVAL(result,smb_vwv3+1,cmd);
 274         return result;
 275 }
 276
 277 /****************************************************************************
 278  Function to do the waiting before sending a local break.
 279 ****************************************************************************/
 280
 281 static void wait_before_sending_break(void)
 282 {
 283         long wait_time = (long)lp_oplock_break_wait_time();
 284
 285         if (wait_time) {
 286                 smb_msleep(wait_time);
 287         }
 288 }
 289
 290 /****************************************************************************
 291  Ensure that we have a valid oplock.
 292 ****************************************************************************/
 293
 294 static files_struct *initial_break_processing(SMB_DEV_T dev, SMB_INO_T inode, unsigned long file_id)
 295 {
 296         files_struct *fsp = NULL;
 297
 298         if( DEBUGLVL( 3 ) ) {
 299                 dbgtext( "initial_break_processing: called for 0x%x/%.0f/%u\n",
 300                         (unsigned int)dev, (double)inode, (int)file_id);
 301                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 302                         exclusive_oplocks_open, level_II_oplocks_open );
 303         }
 304
 305         /*
 306          * We need to search the file open table for the
 307          * entry containing this dev and inode, and ensure
 308          * we have an oplock on it.
 309          */
 310
 311         fsp = file_find_dif(dev, inode, file_id);
 312
 313         if(fsp == NULL) {
 314                 /* The file could have been closed in the meantime - return success. */
 315                 if( DEBUGLVL( 3 ) ) {
 316                         dbgtext( "initial_break_processing: cannot find open file with " );
 317                         dbgtext( "dev = 0x%x, inode = %.0f file_id = %lu", (unsigned int)dev,
 318                                 (double)inode, file_id);
 319                         dbgtext( "allowing break to succeed.\n" );
 320                 }
 321                 return NULL;
 322         }
 323
 324         /* Ensure we have an oplock on the file */
 325
 326         /*
 327          * There is a potential race condition in that an oplock could
 328          * have been broken due to another udp request, and yet there are
 329          * still oplock break messages being sent in the udp message
 330          * queue for this file. So return true if we don't have an oplock,
 331          * as we may have just freed it.
 332          */
 333
 334         if(fsp->oplock_type == NO_OPLOCK) {
 335                 if( DEBUGLVL( 3 ) ) {
 336                         dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
 337                         dbgtext( "(dev = %x, inode = %.0f, file_id = %lu) has no oplock.\n",
 338                                 (unsigned int)dev, (double)inode, fsp->fh->file_id );
 339                         dbgtext( "Allowing break to succeed regardless.\n" );
 340                 }
 341                 return NULL;
 342         }
 343
 344         return fsp;
 345 }
 346
 347 static void oplock_timeout_handler(struct event_context *ctx,
 348                                    struct timed_event *te,
 349                                    const struct timeval *now,
 350                                    void *private_data)
 351 {
 352         files_struct *fsp = (files_struct *)private_data;
 353
 354         /* Remove the timed event handler. */
 355         TALLOC_FREE(fsp->oplock_timeout);
 356         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n", fsp->fsp_name));
 357         global_client_failed_oplock_break = True;
 358         remove_oplock(fsp);
 359         reply_to_oplock_break_requests(fsp);
 360 }
 361
 362 /*******************************************************************
 363  Add a timeout handler waiting for the client reply.
 364 *******************************************************************/
 365
 366 static void add_oplock_timeout_handler(files_struct *fsp)
 367 {
 368         if (fsp->oplock_timeout != NULL) {
 369                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 370                           "around\n"));
 371         }
 372
 373         fsp->oplock_timeout =
 374                 event_add_timed(smbd_event_context(), NULL,
 375                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 376                                 "oplock_timeout_handler",
 377                                 oplock_timeout_handler, fsp);
 378
 379         if (fsp->oplock_timeout == NULL) {
 380                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 381         }
 382 }
 383
 384 /*******************************************************************
 385  This handles the case of a write triggering a break to none
 386  message on a level2 oplock.
 387  When we get this message we may be in any of three states :
 388  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 389  the client for LEVEL2.
 390 *******************************************************************/
 391
 392 static void process_oplock_async_level2_break_message(int msg_type, struct process_id src,
 393                                                       void *buf, size_t len,
 394                                                       void *private_data)
 395 {
 396         struct share_mode_entry msg;
 397         files_struct *fsp;
 398         char *break_msg;
 399         BOOL sign_state;
 400
 401         if (buf == NULL) {
 402                 DEBUG(0, ("Got NULL buffer\n"));
 403                 return;
 404         }
 405
 406         if (len != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 407                 DEBUG(0, ("Got invalid msg len %d\n", (int)len));
 408                 return;
 409         }
 410
 411         /* De-linearize incoming message. */
 412         message_to_share_mode_entry(&msg, (char *)buf);
 413
 414         DEBUG(10, ("Got oplock async level 2 break message from pid %d: 0x%x/%.0f/%lu\n",
 415                    (int)procid_to_pid(&src), (unsigned int)msg.dev,
 416                    (double)msg.inode, msg.share_file_id));
 417
 418         fsp = initial_break_processing(msg.dev, msg.inode,
 419                                        msg.share_file_id);
 420
 421         if (fsp == NULL) {
 422                 /* We hit a race here. Break messages are sent, and before we
 423                  * get to process this message, we have closed the file.
 424                  * No need to reply as this is an async message. */
 425                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 426                 return;
 427         }
 428
 429         if (fsp->oplock_type == NO_OPLOCK) {
 430                 /* We already got a "break to none" message and we've handled it.
 431                  * just ignore. */
 432                 DEBUG(3, ("process_oplock_async_level2_break_message: already broken to none, ignoring.\n"));
 433                 return;
 434         }
 435
 436         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 437                 /* Don't tell the client, just downgrade. */
 438                 DEBUG(3, ("process_oplock_async_level2_break_message: downgrading fake level 2 oplock.\n"));
 439                 remove_oplock(fsp);
 440                 return;
 441         }
 442
 443         /* Ensure we're really at level2 state. */
 444         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 445
 446         /* Now send a break to none message to our client. */
 447
 448         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 449         if (break_msg == NULL) {
 450                 exit_server("Could not talloc break_msg\n");
 451         }
 452
 453         /* Need to wait before sending a break message if we sent ourselves this message. */
 454         if (procid_to_pid(&src) == sys_getpid()) {
 455                 wait_before_sending_break();
 456         }
 457
 458         /* Save the server smb signing state. */
 459         sign_state = srv_oplock_set_signing(False);
 460
 461         show_msg(break_msg);
 462         if (!send_smb(smbd_server_fd(), break_msg)) {
 463                 exit_server_cleanly("oplock_break: send_smb failed.");
 464         }
 465
 466         /* Restore the sign state to what it was. */
 467         srv_oplock_set_signing(sign_state);
 468
 469         TALLOC_FREE(break_msg);
 470
 471         /* Async level2 request, don't send a reply, just remove the oplock. */
 472         remove_oplock(fsp);
 473 }
 474
 475 /*******************************************************************
 476  This handles the generic oplock break message from another smbd.
 477 *******************************************************************/
 478
 479 static void process_oplock_break_message(int msg_type, struct process_id src,
 480                                          void *buf, size_t len,
 481                                          void *private_data)
 482 {
 483         struct share_mode_entry msg;
 484         files_struct *fsp;
 485         char *break_msg;
 486         BOOL break_to_level2 = False;
 487         BOOL sign_state;
 488
 489         if (buf == NULL) {
 490                 DEBUG(0, ("Got NULL buffer\n"));
 491                 return;
 492         }
 493
 494         if (len != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 495                 DEBUG(0, ("Got invalid msg len %d\n", (int)len));
 496                 return;
 497         }
 498
 499         /* De-linearize incoming message. */
 500         message_to_share_mode_entry(&msg, (char *)buf);
 501
 502         DEBUG(10, ("Got oplock break message from pid %d: 0x%x/%.0f/%lu\n",
 503                    (int)procid_to_pid(&src), (unsigned int)msg.dev,
 504                    (double)msg.inode, msg.share_file_id));
 505
 506         fsp = initial_break_processing(msg.dev, msg.inode,
 507                                        msg.share_file_id);
 508
 509         if (fsp == NULL) {
 510                 /* a We hit race here. Break messages are sent, and before we
 511                  * get to process this message, we have closed the file. Reply
 512                  * with 'ok, oplock broken' */
 513                 DEBUG(3, ("Did not find fsp\n"));
 514
 515                 /* We just send the same message back. */
 516                 message_send_pid(src, MSG_SMB_BREAK_RESPONSE,
 517                                  buf, MSG_SMB_SHARE_MODE_ENTRY_SIZE, True);
 518                 return;
 519         }
 520
 521         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 522                 /* Remember we have to inform the requesting PID when the
 523                  * client replies */
 524                 msg.pid = src;
 525                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 526                              &fsp->pending_break_messages,
 527                              &fsp->num_pending_break_messages);
 528                 return;
 529         }
 530
 531         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 532             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 533                 DEBUG(3, ("Already downgraded oplock on 0x%x/%.0f: %s\n",
 534                           (unsigned int)fsp->dev, (double)fsp->inode,
 535                           fsp->fsp_name));
 536                 /* We just send the same message back. */
 537                 message_send_pid(src, MSG_SMB_BREAK_RESPONSE,
 538                                  buf, MSG_SMB_SHARE_MODE_ENTRY_SIZE, True);
 539                 return;
 540         }
 541
 542         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 543             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 544             !koplocks && /* NOTE: we force levelII off for kernel oplocks -
 545                           * this will change when it is supported */
 546             lp_level2_oplocks(SNUM(fsp->conn))) {
 547                 break_to_level2 = True;
 548         }
 549
 550         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 551                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 552         if (break_msg == NULL) {
 553                 exit_server("Could not talloc break_msg\n");
 554         }
 555
 556         /* Need to wait before sending a break message if we sent ourselves this message. */
 557         if (procid_to_pid(&src) == sys_getpid()) {
 558                 wait_before_sending_break();
 559         }
 560
 561         /* Save the server smb signing state. */
 562         sign_state = srv_oplock_set_signing(False);
 563
 564         show_msg(break_msg);
 565         if (!send_smb(smbd_server_fd(), break_msg)) {
 566                 exit_server_cleanly("oplock_break: send_smb failed.");
 567         }
 568
 569         /* Restore the sign state to what it was. */
 570         srv_oplock_set_signing(sign_state);
 571
 572         TALLOC_FREE(break_msg);
 573
 574         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 575
 576         msg.pid = src;
 577         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 578                      &fsp->pending_break_messages,
 579                      &fsp->num_pending_break_messages);
 580
 581         add_oplock_timeout_handler(fsp);
 582 }
 583
 584 /*******************************************************************
 585  This handles the kernel oplock break message.
 586 *******************************************************************/
 587
 588 static void process_kernel_oplock_break(int msg_type, struct process_id src,
 589                                         void *buf, size_t len,
 590                                         void *private_data)
 591 {
 592         SMB_DEV_T dev;
 593         SMB_INO_T inode;
 594         unsigned long file_id;
 595         files_struct *fsp;
 596         char *break_msg;
 597         BOOL sign_state;
 598
 599         if (buf == NULL) {
 600                 DEBUG(0, ("Got NULL buffer\n"));
 601                 return;
 602         }
 603
 604         if (len != MSG_SMB_KERNEL_BREAK_SIZE) {
 605                 DEBUG(0, ("Got invalid msg len %d\n", (int)len));
 606                 return;
 607         }
 608
 609         /* Pull the data from the message. */
 610         dev = DEV_T_VAL(buf, 0);
 611         inode = INO_T_VAL(buf, 8);
 612         file_id = (unsigned long)IVAL(buf, 16);
 613
 614         DEBUG(10, ("Got kernel oplock break message from pid %d: 0x%x/%.0f/%u\n",
 615                    (int)procid_to_pid(&src), (unsigned int)dev, (double)inode,
 616                    (unsigned int)file_id));
 617
 618         fsp = initial_break_processing(dev, inode, file_id);
 619
 620         if (fsp == NULL) {
 621                 DEBUG(3, ("Got a kernel oplock break message for a file "
 622                           "I don't know about\n"));
 623                 return;
 624         }
 625
 626         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 627                 /* This is ok, kernel oplocks come in completely async */
 628                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 629                           "break reply\n"));
 630                 return;
 631         }
 632
 633         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 634         if (break_msg == NULL) {
 635                 exit_server("Could not talloc break_msg\n");
 636         }
 637
 638         /* Save the server smb signing state. */
 639         sign_state = srv_oplock_set_signing(False);
 640
 641         show_msg(break_msg);
 642         if (!send_smb(smbd_server_fd(), break_msg)) {
 643                 exit_server_cleanly("oplock_break: send_smb failed.");
 644         }
 645
 646         /* Restore the sign state to what it was. */
 647         srv_oplock_set_signing(sign_state);
 648
 649         TALLOC_FREE(break_msg);
 650
 651         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 652
 653         add_oplock_timeout_handler(fsp);
 654 }
 655
 656 void reply_to_oplock_break_requests(files_struct *fsp)
 657 {
 658         int i;
 659
 660         for (i=0; i<fsp->num_pending_break_messages; i++) {
 661                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 662                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 663
 664                 share_mode_entry_to_message(msg, e);
 665
 666                 message_send_pid(e->pid, MSG_SMB_BREAK_RESPONSE,
 667                                  msg, MSG_SMB_SHARE_MODE_ENTRY_SIZE, True);
 668         }
 669
 670         SAFE_FREE(fsp->pending_break_messages);
 671         fsp->num_pending_break_messages = 0;
 672         if (fsp->oplock_timeout != NULL) {
 673                 /* Remove the timed event handler. */
 674                 TALLOC_FREE(fsp->oplock_timeout);
 675                 fsp->oplock_timeout = NULL;
 676         }
 677         return;
 678 }
 679
 680 static void process_oplock_break_response(int msg_type, struct process_id src,
 681                                           void *buf, size_t len,
 682                                           void *private_data)
 683 {
 684         struct share_mode_entry msg;
 685
 686         if (buf == NULL) {
 687                 DEBUG(0, ("Got NULL buffer\n"));
 688                 return;
 689         }
 690
 691         if (len != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 692                 DEBUG(0, ("Got invalid msg len %u\n", (unsigned int)len));
 693                 return;
 694         }
 695
 696         /* De-linearize incoming message. */
 697         message_to_share_mode_entry(&msg, (char *)buf);
 698
 699         DEBUG(10, ("Got oplock break response from pid %d: 0x%x/%.0f/%lu mid %u\n",
 700                    (int)procid_to_pid(&src), (unsigned int)msg.dev,
 701                    (double)msg.inode, msg.share_file_id,
 702                    (unsigned int)msg.op_mid));
 703
 704         /* Here's the hack from open.c, store the mid in the 'port' field */
 705         schedule_deferred_open_smb_message(msg.op_mid);
 706 }
 707
 708 static void process_open_retry_message(int msg_type, struct process_id src,
 709                                        void *buf, size_t len,
 710                                        void *private_data)
 711 {
 712         struct share_mode_entry msg;
 713
 714         if (buf == NULL) {
 715                 DEBUG(0, ("Got NULL buffer\n"));
 716                 return;
 717         }
 718
 719         if (len != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 720                 DEBUG(0, ("Got invalid msg len %d\n", (int)len));
 721                 return;
 722         }
 723
 724         /* De-linearize incoming message. */
 725         message_to_share_mode_entry(&msg, (char *)buf);
 726
 727         DEBUG(10, ("Got open retry msg from pid %d: 0x%x/%.0f/%lu mid %u\n",
 728                    (int)procid_to_pid(&src), (unsigned int)msg.dev,
 729                    (double)msg.inode, msg.share_file_id,
 730                    (unsigned int)msg.op_mid));
 731
 732         schedule_deferred_open_smb_message(msg.op_mid);
 733 }
 734
 735 /****************************************************************************
 736  This function is called on any file modification or lock request. If a file
 737  is level 2 oplocked then it must tell all other level 2 holders to break to
 738  none.
 739 ****************************************************************************/
 740
 741 void release_level_2_oplocks_on_change(files_struct *fsp)
 742 {
 743         int i;
 744         struct share_mode_lock *lck;
 745
 746         /*
 747          * If this file is level II oplocked then we need
 748          * to grab the shared memory lock and inform all
 749          * other files with a level II lock that they need
 750          * to flush their read caches. We keep the lock over
 751          * the shared memory area whilst doing this.
 752          */
 753
 754         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 755                 return;
 756
 757         lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);
 758         if (lck == NULL) {
 759                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 760                          "share mode entry for file %s.\n", fsp->fsp_name ));
 761                 return;
 762         }
 763
 764         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 765                   lck->num_share_modes ));
 766
 767         for(i = 0; i < lck->num_share_modes; i++) {
 768                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 769                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 770
 771                 if (!is_valid_share_mode_entry(share_entry)) {
 772                         continue;
 773                 }
 774
 775                 /*
 776                  * As there could have been multiple writes waiting at the
 777                  * lock_share_entry gate we may not be the first to
 778                  * enter. Hence the state of the op_types in the share mode
 779                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 780                  * oplock. It will do no harm to re-send break messages to
 781                  * those smbd's that are still waiting their turn to remove
 782                  * their LEVEL_II state, and also no harm to ignore existing
 783                  * NO_OPLOCK states. JRA.
 784                  */
 785
 786                 DEBUG(10,("release_level_2_oplocks_on_change: "
 787                           "share_entry[%i]->op_type == %d\n",
 788                           i, share_entry->op_type ));
 789
 790                 if (share_entry->op_type == NO_OPLOCK) {
 791                         continue;
 792                 }
 793
 794                 /* Paranoia .... */
 795                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 796                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 797                                  "share mode entry %d is an exlusive "
 798                                  "oplock !\n", i ));
 799                         TALLOC_FREE(lck);
 800                         abort();
 801                 }
 802
 803                 share_mode_entry_to_message(msg, share_entry);
 804
 805                 message_send_pid(share_entry->pid, MSG_SMB_ASYNC_LEVEL2_BREAK,
 806                                  msg, MSG_SMB_SHARE_MODE_ENTRY_SIZE, True);
 807         }
 808
 809         /* We let the message receivers handle removing the oplock state
 810            in the share mode lock db. */
 811
 812         TALLOC_FREE(lck);
 813 }
 814
 815 /****************************************************************************
 816  Linearize a share mode entry struct to an internal oplock break message.
 817 ****************************************************************************/
 818
 819 void share_mode_entry_to_message(char *msg, struct share_mode_entry *e)
 820 {
 821         SIVAL(msg,0,(uint32)e->pid.pid);
 822         SSVAL(msg,4,e->op_mid);
 823         SSVAL(msg,6,e->op_type);
 824         SIVAL(msg,8,e->access_mask);
 825         SIVAL(msg,12,e->share_access);
 826         SIVAL(msg,16,e->private_options);
 827         SIVAL(msg,20,(uint32)e->time.tv_sec);
 828         SIVAL(msg,24,(uint32)e->time.tv_usec);
 829         SDEV_T_VAL(msg,28,e->dev);
 830         SINO_T_VAL(msg,36,e->inode);
 831         SIVAL(msg,44,e->share_file_id);
 832         SIVAL(msg,48,e->uid);
 833         SSVAL(msg,52,e->flags);
 834 }
 835
 836 /****************************************************************************
 837  De-linearize an internal oplock break message to a share mode entry struct.
 838 ****************************************************************************/
 839
 840 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 841 {
 842         e->pid.pid = (pid_t)IVAL(msg,0);
 843         e->op_mid = SVAL(msg,4);
 844         e->op_type = SVAL(msg,6);
 845         e->access_mask = IVAL(msg,8);
 846         e->share_access = IVAL(msg,12);
 847         e->private_options = IVAL(msg,16);
 848         e->time.tv_sec = (time_t)IVAL(msg,20);
 849         e->time.tv_usec = (int)IVAL(msg,24);
 850         e->dev = DEV_T_VAL(msg,28);
 851         e->inode = INO_T_VAL(msg,36);
 852         e->share_file_id = (unsigned long)IVAL(msg,44);
 853         e->uid = (uint32)IVAL(msg,48);
 854         e->flags = (uint16)SVAL(msg,52);
 855 }
 856
 857 /****************************************************************************
 858  Setup oplocks for this process.
 859 ****************************************************************************/
 860
 861 BOOL init_oplocks(void)
 862 {
 863         DEBUG(3,("init_oplocks: initializing messages.\n"));
 864
 865         message_register(MSG_SMB_BREAK_REQUEST,
 866                          process_oplock_break_message,
 867                          NULL);
 868         message_register(MSG_SMB_ASYNC_LEVEL2_BREAK,
 869                          process_oplock_async_level2_break_message,
 870                          NULL);
 871         message_register(MSG_SMB_BREAK_RESPONSE,
 872                          process_oplock_break_response,
 873                          NULL);
 874         message_register(MSG_SMB_KERNEL_BREAK,
 875                          process_kernel_oplock_break,
 876                          NULL);
 877         message_register(MSG_SMB_OPEN_RETRY,
 878                          process_open_retry_message,
 879                          NULL);
 880
 881         if (lp_kernel_oplocks()) {
 882 #if HAVE_KERNEL_OPLOCKS_IRIX
 883                 koplocks = irix_init_kernel_oplocks();
 884 #elif HAVE_KERNEL_OPLOCKS_LINUX
 885                 koplocks = linux_init_kernel_oplocks();
 886 #endif
 887         }
 888
 889         return True;
 890 }