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);
  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);
 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 static 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                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 411         }
 412
 413         /* Restore the sign state to what it was. */
 414         srv_oplock_set_signing(sign_state);
 415
 416         TALLOC_FREE(break_msg);
 417
 418         /* Async level2 request, don't send a reply, just remove the oplock. */
 419         remove_oplock(fsp);
 420 }
 421
 422 /*******************************************************************
 423  This handles the generic oplock break message from another smbd.
 424 *******************************************************************/
 425
 426 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 427                                          void *private_data,
 428                                          uint32_t msg_type,
 429                                          struct server_id src,
 430                                          DATA_BLOB *data)
 431 {
 432         struct share_mode_entry msg;
 433         files_struct *fsp;
 434         char *break_msg;
 435         bool break_to_level2 = False;
 436         bool sign_state;
 437
 438         if (data->data == NULL) {
 439                 DEBUG(0, ("Got NULL buffer\n"));
 440                 return;
 441         }
 442
 443         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 444                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 445                 return;
 446         }
 447
 448         /* De-linearize incoming message. */
 449         message_to_share_mode_entry(&msg, (char *)data->data);
 450
 451         DEBUG(10, ("Got oplock break message from pid %d: %s/%lu\n",
 452                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 453
 454         fsp = initial_break_processing(msg.id, msg.share_file_id);
 455
 456         if (fsp == NULL) {
 457                 /* a We hit race here. Break messages are sent, and before we
 458                  * get to process this message, we have closed the file. Reply
 459                  * with 'ok, oplock broken' */
 460                 DEBUG(3, ("Did not find fsp\n"));
 461
 462                 /* We just send the same message back. */
 463                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 464                                    (uint8 *)data->data,
 465                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 466                 return;
 467         }
 468
 469         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 470                 /* Remember we have to inform the requesting PID when the
 471                  * client replies */
 472                 msg.pid = src;
 473                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 474                              &fsp->pending_break_messages,
 475                              &fsp->num_pending_break_messages);
 476                 return;
 477         }
 478
 479         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 480             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 481                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 482                           file_id_string_tos(&fsp->file_id),
 483                           fsp->fsp_name));
 484                 /* We just send the same message back. */
 485                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 486                                    (uint8 *)data->data,
 487                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 488                 return;
 489         }
 490
 491         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 492             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 493             !koplocks && /* NOTE: we force levelII off for kernel oplocks -
 494                           * this will change when it is supported */
 495             lp_level2_oplocks(SNUM(fsp->conn))) {
 496                 break_to_level2 = True;
 497         }
 498
 499         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 500                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 501         if (break_msg == NULL) {
 502                 exit_server("Could not talloc break_msg\n");
 503         }
 504
 505         /* Need to wait before sending a break message if we sent ourselves this message. */
 506         if (procid_to_pid(&src) == sys_getpid()) {
 507                 wait_before_sending_break();
 508         }
 509
 510         /* Save the server smb signing state. */
 511         sign_state = srv_oplock_set_signing(False);
 512
 513         show_msg(break_msg);
 514         if (!srv_send_smb(smbd_server_fd(),
 515                         break_msg,
 516                         IS_CONN_ENCRYPTED(fsp->conn))) {
 517                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 518         }
 519
 520         /* Restore the sign state to what it was. */
 521         srv_oplock_set_signing(sign_state);
 522
 523         TALLOC_FREE(break_msg);
 524
 525         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 526
 527         msg.pid = src;
 528         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 529                      &fsp->pending_break_messages,
 530                      &fsp->num_pending_break_messages);
 531
 532         add_oplock_timeout_handler(fsp);
 533 }
 534
 535 /*******************************************************************
 536  This handles the kernel oplock break message.
 537 *******************************************************************/
 538
 539 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 540                                         void *private_data,
 541                                         uint32_t msg_type,
 542                                         struct server_id src,
 543                                         DATA_BLOB *data)
 544 {
 545         struct file_id id;
 546         unsigned long file_id;
 547         files_struct *fsp;
 548         char *break_msg;
 549         bool sign_state;
 550
 551         if (data->data == NULL) {
 552                 DEBUG(0, ("Got NULL buffer\n"));
 553                 return;
 554         }
 555
 556         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 557                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 558                 return;
 559         }
 560
 561         /* Pull the data from the message. */
 562         pull_file_id_16((char *)data->data, &id);
 563         file_id = (unsigned long)IVAL(data->data, 16);
 564
 565         DEBUG(10, ("Got kernel oplock break message from pid %d: %s/%u\n",
 566                    (int)procid_to_pid(&src), file_id_string_tos(&id),
 567                    (unsigned int)file_id));
 568
 569         fsp = initial_break_processing(id, file_id);
 570
 571         if (fsp == NULL) {
 572                 DEBUG(3, ("Got a kernel oplock break message for a file "
 573                           "I don't know about\n"));
 574                 return;
 575         }
 576
 577         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 578                 /* This is ok, kernel oplocks come in completely async */
 579                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 580                           "break reply\n"));
 581                 return;
 582         }
 583
 584         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 585         if (break_msg == NULL) {
 586                 exit_server("Could not talloc break_msg\n");
 587         }
 588
 589         /* Save the server smb signing state. */
 590         sign_state = srv_oplock_set_signing(False);
 591
 592         show_msg(break_msg);
 593         if (!srv_send_smb(smbd_server_fd(),
 594                         break_msg,
 595                         IS_CONN_ENCRYPTED(fsp->conn))) {
 596                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 597         }
 598
 599         /* Restore the sign state to what it was. */
 600         srv_oplock_set_signing(sign_state);
 601
 602         TALLOC_FREE(break_msg);
 603
 604         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 605
 606         add_oplock_timeout_handler(fsp);
 607 }
 608
 609 void reply_to_oplock_break_requests(files_struct *fsp)
 610 {
 611         int i;
 612
 613         for (i=0; i<fsp->num_pending_break_messages; i++) {
 614                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 615                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 616
 617                 share_mode_entry_to_message(msg, e);
 618
 619                 messaging_send_buf(smbd_messaging_context(), e->pid,
 620                                    MSG_SMB_BREAK_RESPONSE,
 621                                    (uint8 *)msg,
 622                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 623         }
 624
 625         SAFE_FREE(fsp->pending_break_messages);
 626         fsp->num_pending_break_messages = 0;
 627         if (fsp->oplock_timeout != NULL) {
 628                 /* Remove the timed event handler. */
 629                 TALLOC_FREE(fsp->oplock_timeout);
 630                 fsp->oplock_timeout = NULL;
 631         }
 632         return;
 633 }
 634
 635 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 636                                           void *private_data,
 637                                           uint32_t msg_type,
 638                                           struct server_id src,
 639                                           DATA_BLOB *data)
 640 {
 641         struct share_mode_entry msg;
 642
 643         if (data->data == NULL) {
 644                 DEBUG(0, ("Got NULL buffer\n"));
 645                 return;
 646         }
 647
 648         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 649                 DEBUG(0, ("Got invalid msg len %u\n",
 650                           (unsigned int)data->length));
 651                 return;
 652         }
 653
 654         /* De-linearize incoming message. */
 655         message_to_share_mode_entry(&msg, (char *)data->data);
 656
 657         DEBUG(10, ("Got oplock break response from pid %d: %s/%lu mid %u\n",
 658                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id,
 659                    (unsigned int)msg.op_mid));
 660
 661         /* Here's the hack from open.c, store the mid in the 'port' field */
 662         schedule_deferred_open_smb_message(msg.op_mid);
 663 }
 664
 665 static void process_open_retry_message(struct messaging_context *msg_ctx,
 666                                        void *private_data,
 667                                        uint32_t msg_type,
 668                                        struct server_id src,
 669                                        DATA_BLOB *data)
 670 {
 671         struct share_mode_entry msg;
 672
 673         if (data->data == NULL) {
 674                 DEBUG(0, ("Got NULL buffer\n"));
 675                 return;
 676         }
 677
 678         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 679                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 680                 return;
 681         }
 682
 683         /* De-linearize incoming message. */
 684         message_to_share_mode_entry(&msg, (char *)data->data);
 685
 686         DEBUG(10, ("Got open retry msg from pid %d: %s mid %u\n",
 687                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id),
 688                    (unsigned int)msg.op_mid));
 689
 690         schedule_deferred_open_smb_message(msg.op_mid);
 691 }
 692
 693 /****************************************************************************
 694  This function is called on any file modification or lock request. If a file
 695  is level 2 oplocked then it must tell all other level 2 holders to break to
 696  none.
 697 ****************************************************************************/
 698
 699 void release_level_2_oplocks_on_change(files_struct *fsp)
 700 {
 701         int i;
 702         struct share_mode_lock *lck;
 703
 704         /*
 705          * If this file is level II oplocked then we need
 706          * to grab the shared memory lock and inform all
 707          * other files with a level II lock that they need
 708          * to flush their read caches. We keep the lock over
 709          * the shared memory area whilst doing this.
 710          */
 711
 712         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 713                 return;
 714
 715         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 716                                   NULL);
 717         if (lck == NULL) {
 718                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 719                          "share mode entry for file %s.\n", fsp->fsp_name ));
 720                 return;
 721         }
 722
 723         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 724                   lck->num_share_modes ));
 725
 726         for(i = 0; i < lck->num_share_modes; i++) {
 727                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 728                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 729
 730                 if (!is_valid_share_mode_entry(share_entry)) {
 731                         continue;
 732                 }
 733
 734                 /*
 735                  * As there could have been multiple writes waiting at the
 736                  * lock_share_entry gate we may not be the first to
 737                  * enter. Hence the state of the op_types in the share mode
 738                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 739                  * oplock. It will do no harm to re-send break messages to
 740                  * those smbd's that are still waiting their turn to remove
 741                  * their LEVEL_II state, and also no harm to ignore existing
 742                  * NO_OPLOCK states. JRA.
 743                  */
 744
 745                 DEBUG(10,("release_level_2_oplocks_on_change: "
 746                           "share_entry[%i]->op_type == %d\n",
 747                           i, share_entry->op_type ));
 748
 749                 if (share_entry->op_type == NO_OPLOCK) {
 750                         continue;
 751                 }
 752
 753                 /* Paranoia .... */
 754                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 755                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 756                                  "share mode entry %d is an exlusive "
 757                                  "oplock !\n", i ));
 758                         TALLOC_FREE(lck);
 759                         abort();
 760                 }
 761
 762                 share_mode_entry_to_message(msg, share_entry);
 763
 764                 /*
 765                  * Deal with a race condition when breaking level2
 766                  * oplocks. Don't send all the messages and release
 767                  * the lock, this allows someone else to come in and
 768                  * get a level2 lock before any of the messages are
 769                  * processed, and thus miss getting a break message.
 770                  * Ensure at least one entry (the one we're breaking)
 771                  * is processed immediately under the lock and becomes
 772                  * set as NO_OPLOCK to stop any waiter getting a level2.
 773                  * Bugid #5980.
 774                  */
 775
 776                 if (procid_is_me(&share_entry->pid)) {
 777                         DATA_BLOB blob = data_blob_const(msg,
 778                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 779                         process_oplock_async_level2_break_message(smbd_messaging_context(),
 780                                                 NULL,
 781                                                 MSG_SMB_ASYNC_LEVEL2_BREAK,
 782                                                 share_entry->pid,
 783                                                 &blob);
 784                 } else {
 785                         messaging_send_buf(smbd_messaging_context(),
 786                                         share_entry->pid,
 787                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 788                                         (uint8 *)msg,
 789                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 790                 }
 791         }
 792
 793         /* We let the message receivers handle removing the oplock state
 794            in the share mode lock db. */
 795
 796         TALLOC_FREE(lck);
 797 }
 798
 799 /****************************************************************************
 800  Linearize a share mode entry struct to an internal oplock break message.
 801 ****************************************************************************/
 802
 803 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 804 {
 805         SIVAL(msg,0,(uint32)e->pid.pid);
 806         SSVAL(msg,4,e->op_mid);
 807         SSVAL(msg,6,e->op_type);
 808         SIVAL(msg,8,e->access_mask);
 809         SIVAL(msg,12,e->share_access);
 810         SIVAL(msg,16,e->private_options);
 811         SIVAL(msg,20,(uint32)e->time.tv_sec);
 812         SIVAL(msg,24,(uint32)e->time.tv_usec);
 813         push_file_id_16(msg+28, &e->id);
 814         SIVAL(msg,44,e->share_file_id);
 815         SIVAL(msg,48,e->uid);
 816         SSVAL(msg,52,e->flags);
 817 #ifdef CLUSTER_SUPPORT
 818         SIVAL(msg,54,e->pid.vnn);
 819 #endif
 820 }
 821
 822 /****************************************************************************
 823  De-linearize an internal oplock break message to a share mode entry struct.
 824 ****************************************************************************/
 825
 826 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 827 {
 828         e->pid.pid = (pid_t)IVAL(msg,0);
 829         e->op_mid = SVAL(msg,4);
 830         e->op_type = SVAL(msg,6);
 831         e->access_mask = IVAL(msg,8);
 832         e->share_access = IVAL(msg,12);
 833         e->private_options = IVAL(msg,16);
 834         e->time.tv_sec = (time_t)IVAL(msg,20);
 835         e->time.tv_usec = (int)IVAL(msg,24);
 836         pull_file_id_16(msg+28, &e->id);
 837         e->share_file_id = (unsigned long)IVAL(msg,44);
 838         e->uid = (uint32)IVAL(msg,48);
 839         e->flags = (uint16)SVAL(msg,52);
 840 #ifdef CLUSTER_SUPPORT
 841         e->pid.vnn = IVAL(msg,54);
 842 #endif
 843 }
 844
 845 /****************************************************************************
 846  Setup oplocks for this process.
 847 ****************************************************************************/
 848
 849 bool init_oplocks(struct messaging_context *msg_ctx)
 850 {
 851         DEBUG(3,("init_oplocks: initializing messages.\n"));
 852
 853         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 854                            process_oplock_break_message);
 855         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 856                            process_oplock_async_level2_break_message);
 857         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 858                            process_oplock_break_response);
 859         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 860                            process_kernel_oplock_break);
 861         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 862                            process_open_retry_message);
 863
 864         if (lp_kernel_oplocks()) {
 865 #if HAVE_KERNEL_OPLOCKS_IRIX
 866                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 867 #elif HAVE_KERNEL_OPLOCKS_LINUX
 868                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 869 #endif
 870         }
 871
 872         return True;
 873 }