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_16((char *)msg, &fsp->file_id);
  44         SIVAL(msg,16,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 (koplocks) {
 126                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 127         }
 128         fsp->oplock_type = LEVEL_II_OPLOCK;
 129         exclusive_oplocks_open--;
 130         level_II_oplocks_open++;
 131         fsp->sent_oplock_break = NO_BREAK_SENT;
 132 }
 133
 134 /****************************************************************************
 135  Remove a file oplock. Copes with level II and exclusive.
 136  Locks then unlocks the share mode lock. Client can decide to go directly
 137  to none even if a "break-to-level II" was sent.
 138 ****************************************************************************/
 139
 140 bool remove_oplock(files_struct *fsp)
 141 {
 142         bool ret;
 143         struct share_mode_lock *lck;
 144
 145         /* Remove the oplock flag from the sharemode. */
 146         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 147                                   NULL);
 148         if (lck == NULL) {
 149                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 150                          "file %s\n", fsp->fsp_name ));
 151                 return False;
 152         }
 153         ret = remove_share_oplock(lck, fsp);
 154         if (!ret) {
 155                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 156                          "file %s fnum %d, %s\n",
 157                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 158         }
 159         release_file_oplock(fsp);
 160         TALLOC_FREE(lck);
 161         return ret;
 162 }
 163
 164 /*
 165  * Deal with a reply when a break-to-level II was sent.
 166  */
 167 bool downgrade_oplock(files_struct *fsp)
 168 {
 169         bool ret;
 170         struct share_mode_lock *lck;
 171
 172         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 173                                   NULL);
 174         if (lck == NULL) {
 175                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 176                          "file %s\n", fsp->fsp_name ));
 177                 return False;
 178         }
 179         ret = downgrade_share_oplock(lck, fsp);
 180         if (!ret) {
 181                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 182                          "for file %s fnum %d, file_id %s\n",
 183                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 184         }
 185
 186         downgrade_file_oplock(fsp);
 187         TALLOC_FREE(lck);
 188         return ret;
 189 }
 190
 191 /****************************************************************************
 192  Set up an oplock break message.
 193 ****************************************************************************/
 194
 195 static char *new_break_smb_message(TALLOC_CTX *mem_ctx,
 196                                    files_struct *fsp, uint8 cmd)
 197 {
 198         char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
 199
 200         if (result == NULL) {
 201                 DEBUG(0, ("talloc failed\n"));
 202                 return NULL;
 203         }
 204
 205         memset(result,'\0',smb_size);
 206         srv_set_message(result,8,0,true);
 207         SCVAL(result,smb_com,SMBlockingX);
 208         SSVAL(result,smb_tid,fsp->conn->cnum);
 209         SSVAL(result,smb_pid,0xFFFF);
 210         SSVAL(result,smb_uid,0);
 211         SSVAL(result,smb_mid,0xFFFF);
 212         SCVAL(result,smb_vwv0,0xFF);
 213         SSVAL(result,smb_vwv2,fsp->fnum);
 214         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 215         SCVAL(result,smb_vwv3+1,cmd);
 216         return result;
 217 }
 218
 219 /****************************************************************************
 220  Function to do the waiting before sending a local break.
 221 ****************************************************************************/
 222
 223 static void wait_before_sending_break(void)
 224 {
 225         long wait_time = (long)lp_oplock_break_wait_time();
 226
 227         if (wait_time) {
 228                 smb_msleep(wait_time);
 229         }
 230 }
 231
 232 /****************************************************************************
 233  Ensure that we have a valid oplock.
 234 ****************************************************************************/
 235
 236 static files_struct *initial_break_processing(struct file_id id, unsigned long file_id)
 237 {
 238         files_struct *fsp = NULL;
 239
 240         if( DEBUGLVL( 3 ) ) {
 241                 dbgtext( "initial_break_processing: called for %s/%u\n",
 242                          file_id_string_tos(&id), (int)file_id);
 243                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 244                         exclusive_oplocks_open, level_II_oplocks_open );
 245         }
 246
 247         /*
 248          * We need to search the file open table for the
 249          * entry containing this dev and inode, and ensure
 250          * we have an oplock on it.
 251          */
 252
 253         fsp = file_find_dif(id, file_id);
 254
 255         if(fsp == NULL) {
 256                 /* The file could have been closed in the meantime - return success. */
 257                 if( DEBUGLVL( 3 ) ) {
 258                         dbgtext( "initial_break_processing: cannot find open file with " );
 259                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 260                         dbgtext( "allowing break to succeed.\n" );
 261                 }
 262                 return NULL;
 263         }
 264
 265         /* Ensure we have an oplock on the file */
 266
 267         /*
 268          * There is a potential race condition in that an oplock could
 269          * have been broken due to another udp request, and yet there are
 270          * still oplock break messages being sent in the udp message
 271          * queue for this file. So return true if we don't have an oplock,
 272          * as we may have just freed it.
 273          */
 274
 275         if(fsp->oplock_type == NO_OPLOCK) {
 276                 if( DEBUGLVL( 3 ) ) {
 277                         dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
 278                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 279                                  file_id_string_tos(&id), fsp->fh->gen_id );
 280                         dbgtext( "Allowing break to succeed regardless.\n" );
 281                 }
 282                 return NULL;
 283         }
 284
 285         return fsp;
 286 }
 287
 288 static void oplock_timeout_handler(struct event_context *ctx,
 289                                    struct timed_event *te,
 290                                    struct timeval now,
 291                                    void *private_data)
 292 {
 293         files_struct *fsp = (files_struct *)private_data;
 294
 295         /* Remove the timed event handler. */
 296         TALLOC_FREE(fsp->oplock_timeout);
 297         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n", fsp->fsp_name));
 298         global_client_failed_oplock_break = True;
 299         remove_oplock(fsp);
 300         reply_to_oplock_break_requests(fsp);
 301 }
 302
 303 /*******************************************************************
 304  Add a timeout handler waiting for the client reply.
 305 *******************************************************************/
 306
 307 static void add_oplock_timeout_handler(files_struct *fsp)
 308 {
 309         if (fsp->oplock_timeout != NULL) {
 310                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 311                           "around\n"));
 312         }
 313
 314         fsp->oplock_timeout =
 315                 event_add_timed(smbd_event_context(), NULL,
 316                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 317                                 oplock_timeout_handler, fsp);
 318
 319         if (fsp->oplock_timeout == NULL) {
 320                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 321         }
 322 }
 323
 324 /*******************************************************************
 325  This handles the case of a write triggering a break to none
 326  message on a level2 oplock.
 327  When we get this message we may be in any of three states :
 328  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 329  the client for LEVEL2.
 330 *******************************************************************/
 331
 332 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 333                                                       void *private_data,
 334                                                       uint32_t msg_type,
 335                                                       struct server_id src,
 336                                                       DATA_BLOB *data)
 337 {
 338         struct share_mode_entry msg;
 339         files_struct *fsp;
 340         char *break_msg;
 341         bool sign_state;
 342
 343         if (data->data == NULL) {
 344                 DEBUG(0, ("Got NULL buffer\n"));
 345                 return;
 346         }
 347
 348         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 349                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 350                 return;
 351         }
 352
 353         /* De-linearize incoming message. */
 354         message_to_share_mode_entry(&msg, (char *)data->data);
 355
 356         DEBUG(10, ("Got oplock async level 2 break message from pid %d: %s/%lu\n",
 357                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 358
 359         fsp = initial_break_processing(msg.id, msg.share_file_id);
 360
 361         if (fsp == NULL) {
 362                 /* We hit a race here. Break messages are sent, and before we
 363                  * get to process this message, we have closed the file.
 364                  * No need to reply as this is an async message. */
 365                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 366                 return;
 367         }
 368
 369         if (fsp->oplock_type == NO_OPLOCK) {
 370                 /* We already got a "break to none" message and we've handled it.
 371                  * just ignore. */
 372                 DEBUG(3, ("process_oplock_async_level2_break_message: already broken to none, ignoring.\n"));
 373                 return;
 374         }
 375
 376         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 377                 /* Don't tell the client, just downgrade. */
 378                 DEBUG(3, ("process_oplock_async_level2_break_message: downgrading fake level 2 oplock.\n"));
 379                 remove_oplock(fsp);
 380                 return;
 381         }
 382
 383         /* Ensure we're really at level2 state. */
 384         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 385
 386         DEBUG(10,("process_oplock_async_level2_break_message: sending break to "
 387                 "none message for fid %d, file %s\n",
 388                 fsp->fnum,
 389                 fsp->fsp_name));
 390
 391         /* Now send a break to none message to our client. */
 392
 393         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 394         if (break_msg == NULL) {
 395                 exit_server("Could not talloc break_msg\n");
 396         }
 397
 398         /* Need to wait before sending a break message if we sent ourselves this message. */
 399         if (procid_to_pid(&src) == sys_getpid()) {
 400                 wait_before_sending_break();
 401         }
 402
 403         /* Save the server smb signing state. */
 404         sign_state = srv_oplock_set_signing(False);
 405
 406         show_msg(break_msg);
 407         if (!srv_send_smb(smbd_server_fd(),
 408                         break_msg,
 409                         IS_CONN_ENCRYPTED(fsp->conn),
 410                         NULL)) {
 411                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 412         }
 413
 414         /* Restore the sign state to what it was. */
 415         srv_oplock_set_signing(sign_state);
 416
 417         TALLOC_FREE(break_msg);
 418
 419         /* Async level2 request, don't send a reply, just remove the oplock. */
 420         remove_oplock(fsp);
 421 }
 422
 423 /*******************************************************************
 424  This handles the generic oplock break message from another smbd.
 425 *******************************************************************/
 426
 427 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 428                                          void *private_data,
 429                                          uint32_t msg_type,
 430                                          struct server_id src,
 431                                          DATA_BLOB *data)
 432 {
 433         struct share_mode_entry msg;
 434         files_struct *fsp;
 435         char *break_msg;
 436         bool break_to_level2 = False;
 437         bool sign_state;
 438
 439         if (data->data == NULL) {
 440                 DEBUG(0, ("Got NULL buffer\n"));
 441                 return;
 442         }
 443
 444         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 445                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 446                 return;
 447         }
 448
 449         /* De-linearize incoming message. */
 450         message_to_share_mode_entry(&msg, (char *)data->data);
 451
 452         DEBUG(10, ("Got oplock break message from pid %d: %s/%lu\n",
 453                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 454
 455         fsp = initial_break_processing(msg.id, msg.share_file_id);
 456
 457         if (fsp == NULL) {
 458                 /* a We hit race here. Break messages are sent, and before we
 459                  * get to process this message, we have closed the file. Reply
 460                  * with 'ok, oplock broken' */
 461                 DEBUG(3, ("Did not find fsp\n"));
 462
 463                 /* We just send the same message back. */
 464                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 465                                    (uint8 *)data->data,
 466                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 467                 return;
 468         }
 469
 470         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 471                 /* Remember we have to inform the requesting PID when the
 472                  * client replies */
 473                 msg.pid = src;
 474                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 475                              &fsp->pending_break_messages,
 476                              &fsp->num_pending_break_messages);
 477                 return;
 478         }
 479
 480         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 481             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 482                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 483                           file_id_string_tos(&fsp->file_id),
 484                           fsp->fsp_name));
 485                 /* We just send the same message back. */
 486                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 487                                    (uint8 *)data->data,
 488                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 489                 return;
 490         }
 491
 492         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 493             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 494             !koplocks && /* NOTE: we force levelII off for kernel oplocks -
 495                           * this will change when it is supported */
 496             lp_level2_oplocks(SNUM(fsp->conn))) {
 497                 break_to_level2 = True;
 498         }
 499
 500         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 501                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 502         if (break_msg == NULL) {
 503                 exit_server("Could not talloc break_msg\n");
 504         }
 505
 506         /* Need to wait before sending a break message if we sent ourselves this message. */
 507         if (procid_to_pid(&src) == sys_getpid()) {
 508                 wait_before_sending_break();
 509         }
 510
 511         /* Save the server smb signing state. */
 512         sign_state = srv_oplock_set_signing(False);
 513
 514         show_msg(break_msg);
 515         if (!srv_send_smb(smbd_server_fd(),
 516                         break_msg,
 517                         IS_CONN_ENCRYPTED(fsp->conn),
 518                         NULL)) {
 519                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 520         }
 521
 522         /* Restore the sign state to what it was. */
 523         srv_oplock_set_signing(sign_state);
 524
 525         TALLOC_FREE(break_msg);
 526
 527         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 528
 529         msg.pid = src;
 530         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 531                      &fsp->pending_break_messages,
 532                      &fsp->num_pending_break_messages);
 533
 534         add_oplock_timeout_handler(fsp);
 535 }
 536
 537 /*******************************************************************
 538  This handles the kernel oplock break message.
 539 *******************************************************************/
 540
 541 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 542                                         void *private_data,
 543                                         uint32_t msg_type,
 544                                         struct server_id src,
 545                                         DATA_BLOB *data)
 546 {
 547         struct file_id id;
 548         unsigned long file_id;
 549         files_struct *fsp;
 550         char *break_msg;
 551         bool sign_state;
 552
 553         if (data->data == NULL) {
 554                 DEBUG(0, ("Got NULL buffer\n"));
 555                 return;
 556         }
 557
 558         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 559                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 560                 return;
 561         }
 562
 563         /* Pull the data from the message. */
 564         pull_file_id_16((char *)data->data, &id);
 565         file_id = (unsigned long)IVAL(data->data, 16);
 566
 567         DEBUG(10, ("Got kernel oplock break message from pid %d: %s/%u\n",
 568                    (int)procid_to_pid(&src), file_id_string_tos(&id),
 569                    (unsigned int)file_id));
 570
 571         fsp = initial_break_processing(id, file_id);
 572
 573         if (fsp == NULL) {
 574                 DEBUG(3, ("Got a kernel oplock break message for a file "
 575                           "I don't know about\n"));
 576                 return;
 577         }
 578
 579         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 580                 /* This is ok, kernel oplocks come in completely async */
 581                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 582                           "break reply\n"));
 583                 return;
 584         }
 585
 586         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 587         if (break_msg == NULL) {
 588                 exit_server("Could not talloc break_msg\n");
 589         }
 590
 591         /* Save the server smb signing state. */
 592         sign_state = srv_oplock_set_signing(False);
 593
 594         show_msg(break_msg);
 595         if (!srv_send_smb(smbd_server_fd(),
 596                         break_msg,
 597                         IS_CONN_ENCRYPTED(fsp->conn),
 598                         NULL)) {
 599                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 600         }
 601
 602         /* Restore the sign state to what it was. */
 603         srv_oplock_set_signing(sign_state);
 604
 605         TALLOC_FREE(break_msg);
 606
 607         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 608
 609         add_oplock_timeout_handler(fsp);
 610 }
 611
 612 void reply_to_oplock_break_requests(files_struct *fsp)
 613 {
 614         int i;
 615
 616         for (i=0; i<fsp->num_pending_break_messages; i++) {
 617                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 618                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 619
 620                 share_mode_entry_to_message(msg, e);
 621
 622                 messaging_send_buf(smbd_messaging_context(), e->pid,
 623                                    MSG_SMB_BREAK_RESPONSE,
 624                                    (uint8 *)msg,
 625                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 626         }
 627
 628         SAFE_FREE(fsp->pending_break_messages);
 629         fsp->num_pending_break_messages = 0;
 630         if (fsp->oplock_timeout != NULL) {
 631                 /* Remove the timed event handler. */
 632                 TALLOC_FREE(fsp->oplock_timeout);
 633                 fsp->oplock_timeout = NULL;
 634         }
 635         return;
 636 }
 637
 638 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 639                                           void *private_data,
 640                                           uint32_t msg_type,
 641                                           struct server_id src,
 642                                           DATA_BLOB *data)
 643 {
 644         struct share_mode_entry msg;
 645
 646         if (data->data == NULL) {
 647                 DEBUG(0, ("Got NULL buffer\n"));
 648                 return;
 649         }
 650
 651         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 652                 DEBUG(0, ("Got invalid msg len %u\n",
 653                           (unsigned int)data->length));
 654                 return;
 655         }
 656
 657         /* De-linearize incoming message. */
 658         message_to_share_mode_entry(&msg, (char *)data->data);
 659
 660         DEBUG(10, ("Got oplock break response from pid %d: %s/%lu mid %u\n",
 661                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id,
 662                    (unsigned int)msg.op_mid));
 663
 664         /* Here's the hack from open.c, store the mid in the 'port' field */
 665         schedule_deferred_open_smb_message(msg.op_mid);
 666 }
 667
 668 static void process_open_retry_message(struct messaging_context *msg_ctx,
 669                                        void *private_data,
 670                                        uint32_t msg_type,
 671                                        struct server_id src,
 672                                        DATA_BLOB *data)
 673 {
 674         struct share_mode_entry msg;
 675
 676         if (data->data == NULL) {
 677                 DEBUG(0, ("Got NULL buffer\n"));
 678                 return;
 679         }
 680
 681         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 682                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 683                 return;
 684         }
 685
 686         /* De-linearize incoming message. */
 687         message_to_share_mode_entry(&msg, (char *)data->data);
 688
 689         DEBUG(10, ("Got open retry msg from pid %d: %s mid %u\n",
 690                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id),
 691                    (unsigned int)msg.op_mid));
 692
 693         schedule_deferred_open_smb_message(msg.op_mid);
 694 }
 695
 696 /****************************************************************************
 697  This function is called on any file modification or lock request. If a file
 698  is level 2 oplocked then it must tell all other level 2 holders to break to
 699  none.
 700 ****************************************************************************/
 701
 702 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 703                                               enum level2_contention_type type)
 704 {
 705         int i;
 706         struct share_mode_lock *lck;
 707
 708         /*
 709          * If this file is level II oplocked then we need
 710          * to grab the shared memory lock and inform all
 711          * other files with a level II lock that they need
 712          * to flush their read caches. We keep the lock over
 713          * the shared memory area whilst doing this.
 714          */
 715
 716         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 717                 return;
 718
 719         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 720                                   NULL);
 721         if (lck == NULL) {
 722                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 723                          "share mode entry for file %s.\n", fsp->fsp_name ));
 724                 return;
 725         }
 726
 727         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 728                   lck->num_share_modes ));
 729
 730         for(i = 0; i < lck->num_share_modes; i++) {
 731                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 732                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 733
 734                 if (!is_valid_share_mode_entry(share_entry)) {
 735                         continue;
 736                 }
 737
 738                 /*
 739                  * As there could have been multiple writes waiting at the
 740                  * lock_share_entry gate we may not be the first to
 741                  * enter. Hence the state of the op_types in the share mode
 742                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 743                  * oplock. It will do no harm to re-send break messages to
 744                  * those smbd's that are still waiting their turn to remove
 745                  * their LEVEL_II state, and also no harm to ignore existing
 746                  * NO_OPLOCK states. JRA.
 747                  */
 748
 749                 DEBUG(10,("release_level_2_oplocks_on_change: "
 750                           "share_entry[%i]->op_type == %d\n",
 751                           i, share_entry->op_type ));
 752
 753                 if (share_entry->op_type == NO_OPLOCK) {
 754                         continue;
 755                 }
 756
 757                 /* Paranoia .... */
 758                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 759                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 760                                  "share mode entry %d is an exlusive "
 761                                  "oplock !\n", i ));
 762                         TALLOC_FREE(lck);
 763                         abort();
 764                 }
 765
 766                 share_mode_entry_to_message(msg, share_entry);
 767
 768                 /*
 769                  * Deal with a race condition when breaking level2
 770                  * oplocks. Don't send all the messages and release
 771                  * the lock, this allows someone else to come in and
 772                  * get a level2 lock before any of the messages are
 773                  * processed, and thus miss getting a break message.
 774                  * Ensure at least one entry (the one we're breaking)
 775                  * is processed immediately under the lock and becomes
 776                  * set as NO_OPLOCK to stop any waiter getting a level2.
 777                  * Bugid #5980.
 778                  */
 779
 780                 if (procid_is_me(&share_entry->pid)) {
 781                         DATA_BLOB blob = data_blob_const(msg,
 782                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 783                         process_oplock_async_level2_break_message(smbd_messaging_context(),
 784                                                 NULL,
 785                                                 MSG_SMB_ASYNC_LEVEL2_BREAK,
 786                                                 share_entry->pid,
 787                                                 &blob);
 788                 } else {
 789                         messaging_send_buf(smbd_messaging_context(),
 790                                         share_entry->pid,
 791                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 792                                         (uint8 *)msg,
 793                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 794                 }
 795         }
 796
 797         /* We let the message receivers handle removing the oplock state
 798            in the share mode lock db. */
 799
 800         TALLOC_FREE(lck);
 801 }
 802
 803 void contend_level2_oplocks_begin(files_struct *fsp,
 804                                   enum level2_contention_type type)
 805 {
 806         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 807                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 808                 return;
 809         }
 810
 811         contend_level2_oplocks_begin_default(fsp, type);
 812 }
 813
 814 void contend_level2_oplocks_end(files_struct *fsp,
 815                                 enum level2_contention_type type)
 816 {
 817         /* Only kernel oplocks implement this so far */
 818         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 819                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 820         }
 821 }
 822
 823 /****************************************************************************
 824  Linearize a share mode entry struct to an internal oplock break message.
 825 ****************************************************************************/
 826
 827 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 828 {
 829         SIVAL(msg,0,(uint32)e->pid.pid);
 830         SSVAL(msg,4,e->op_mid);
 831         SSVAL(msg,6,e->op_type);
 832         SIVAL(msg,8,e->access_mask);
 833         SIVAL(msg,12,e->share_access);
 834         SIVAL(msg,16,e->private_options);
 835         SIVAL(msg,20,(uint32)e->time.tv_sec);
 836         SIVAL(msg,24,(uint32)e->time.tv_usec);
 837         push_file_id_16(msg+28, &e->id);
 838         SIVAL(msg,44,e->share_file_id);
 839         SIVAL(msg,48,e->uid);
 840         SSVAL(msg,52,e->flags);
 841 #ifdef CLUSTER_SUPPORT
 842         SIVAL(msg,54,e->pid.vnn);
 843 #endif
 844 }
 845
 846 /****************************************************************************
 847  De-linearize an internal oplock break message to a share mode entry struct.
 848 ****************************************************************************/
 849
 850 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 851 {
 852         e->pid.pid = (pid_t)IVAL(msg,0);
 853         e->op_mid = SVAL(msg,4);
 854         e->op_type = SVAL(msg,6);
 855         e->access_mask = IVAL(msg,8);
 856         e->share_access = IVAL(msg,12);
 857         e->private_options = IVAL(msg,16);
 858         e->time.tv_sec = (time_t)IVAL(msg,20);
 859         e->time.tv_usec = (int)IVAL(msg,24);
 860         pull_file_id_16(msg+28, &e->id);
 861         e->share_file_id = (unsigned long)IVAL(msg,44);
 862         e->uid = (uint32)IVAL(msg,48);
 863         e->flags = (uint16)SVAL(msg,52);
 864 #ifdef CLUSTER_SUPPORT
 865         e->pid.vnn = IVAL(msg,54);
 866 #endif
 867 }
 868
 869 /****************************************************************************
 870  Setup oplocks for this process.
 871 ****************************************************************************/
 872
 873 bool init_oplocks(struct messaging_context *msg_ctx)
 874 {
 875         DEBUG(3,("init_oplocks: initializing messages.\n"));
 876
 877         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 878                            process_oplock_break_message);
 879         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 880                            process_oplock_async_level2_break_message);
 881         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 882                            process_oplock_break_response);
 883         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 884                            process_kernel_oplock_break);
 885         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 886                            process_open_retry_message);
 887
 888         if (lp_kernel_oplocks()) {
 889 #if HAVE_KERNEL_OPLOCKS_IRIX
 890                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 891 #elif HAVE_KERNEL_OPLOCKS_LINUX
 892                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 893 #endif
 894         }
 895
 896         return True;
 897 }