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/smbd.h"
  25 #include "smbd/globals.h"
  26 #include "messages.h"
  27 #include "../librpc/gen_ndr/open_files.h"
  28
  29 /****************************************************************************
  30  Get the number of current exclusive oplocks.
  31 ****************************************************************************/
  32
  33 int32 get_number_of_exclusive_open_oplocks(void)
  34 {
  35   return exclusive_oplocks_open;
  36 }
  37
  38 /*
  39  * helper function used by the kernel oplock backends to post the break message
  40  */
  41 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  42 {
  43         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  44
  45         /* Put the kernel break info into the message. */
  46         push_file_id_24((char *)msg, &fsp->file_id);
  47         SIVAL(msg,24,fsp->fh->gen_id);
  48
  49         /* Don't need to be root here as we're only ever
  50            sending to ourselves. */
  51
  52         messaging_send_buf(msg_ctx, messaging_server_id(msg_ctx),
  53                            MSG_SMB_KERNEL_BREAK,
  54                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  55 }
  56
  57 /****************************************************************************
  58  Attempt to set an oplock on a file. Succeeds if kernel oplocks are
  59  disabled (just sets flags) and no byte-range locks in the file. Returns True
  60  if oplock set.
  61 ****************************************************************************/
  62
  63 bool set_file_oplock(files_struct *fsp, int oplock_type)
  64 {
  65         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  66                 if (koplocks &&
  67                     !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
  68                         DEBUG(10, ("Refusing level2 oplock, kernel oplocks "
  69                                    "don't support them\n"));
  70                         return false;
  71                 }
  72         }
  73
  74         if ((fsp->oplock_type != NO_OPLOCK) &&
  75             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  76             koplocks &&
  77             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
  78                 return False;
  79         }
  80
  81         fsp->oplock_type = oplock_type;
  82         fsp->sent_oplock_break = NO_BREAK_SENT;
  83         if (oplock_type == LEVEL_II_OPLOCK) {
  84                 level_II_oplocks_open++;
  85         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  86                 exclusive_oplocks_open++;
  87         }
  88
  89         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  90                     "tv_sec = %x, tv_usec = %x\n",
  91                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  92                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  93                  (int)fsp->open_time.tv_usec ));
  94
  95         return True;
  96 }
  97
  98 /****************************************************************************
  99  Attempt to release an oplock on a file. Decrements oplock count.
 100 ****************************************************************************/
 101
 102 void release_file_oplock(files_struct *fsp)
 103 {
 104         if ((fsp->oplock_type != NO_OPLOCK) &&
 105             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 106             koplocks) {
 107                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 108         }
 109
 110         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 111                 level_II_oplocks_open--;
 112         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 113                 exclusive_oplocks_open--;
 114         }
 115
 116         SMB_ASSERT(exclusive_oplocks_open>=0);
 117         SMB_ASSERT(level_II_oplocks_open>=0);
 118
 119         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 120                 /* This doesn't matter for close. */
 121                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 122         } else {
 123                 fsp->oplock_type = NO_OPLOCK;
 124         }
 125         fsp->sent_oplock_break = NO_BREAK_SENT;
 126
 127         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 128         delete_write_cache(fsp);
 129
 130         TALLOC_FREE(fsp->oplock_timeout);
 131 }
 132
 133 /****************************************************************************
 134  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 135 ****************************************************************************/
 136
 137 static void downgrade_file_oplock(files_struct *fsp)
 138 {
 139         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 140                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 141                 return;
 142         }
 143
 144         if (koplocks) {
 145                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 146         }
 147         fsp->oplock_type = LEVEL_II_OPLOCK;
 148         exclusive_oplocks_open--;
 149         level_II_oplocks_open++;
 150         fsp->sent_oplock_break = NO_BREAK_SENT;
 151 }
 152
 153 /****************************************************************************
 154  Remove a file oplock. Copes with level II and exclusive.
 155  Locks then unlocks the share mode lock. Client can decide to go directly
 156  to none even if a "break-to-level II" was sent.
 157 ****************************************************************************/
 158
 159 bool remove_oplock(files_struct *fsp)
 160 {
 161         bool ret;
 162         struct share_mode_lock *lck;
 163
 164         /* Remove the oplock flag from the sharemode. */
 165         lck = get_share_mode_lock(talloc_tos(), fsp->file_id);
 166         if (lck == NULL) {
 167                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 168                          "file %s\n", fsp_str_dbg(fsp)));
 169                 return False;
 170         }
 171         ret = remove_share_oplock(lck, fsp);
 172         if (!ret) {
 173                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 174                          "file %s fnum %d, %s\n",
 175                          fsp_str_dbg(fsp), fsp->fnum,
 176                          file_id_string_tos(&fsp->file_id)));
 177         }
 178         release_file_oplock(fsp);
 179         TALLOC_FREE(lck);
 180         return ret;
 181 }
 182
 183 /*
 184  * Deal with a reply when a break-to-level II was sent.
 185  */
 186 bool downgrade_oplock(files_struct *fsp)
 187 {
 188         bool ret;
 189         struct share_mode_lock *lck;
 190
 191         lck = get_share_mode_lock(talloc_tos(), fsp->file_id);
 192         if (lck == NULL) {
 193                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 194                          "file %s\n", fsp_str_dbg(fsp)));
 195                 return False;
 196         }
 197         ret = downgrade_share_oplock(lck, fsp);
 198         if (!ret) {
 199                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 200                          "for file %s fnum %d, file_id %s\n",
 201                          fsp_str_dbg(fsp), fsp->fnum,
 202                          file_id_string_tos(&fsp->file_id)));
 203         }
 204
 205         downgrade_file_oplock(fsp);
 206         TALLOC_FREE(lck);
 207         return ret;
 208 }
 209
 210 /*
 211  * Some kernel oplock implementations handle the notification themselves.
 212  */
 213 bool should_notify_deferred_opens()
 214 {
 215         return !(koplocks &&
 216                 (koplocks->flags & KOPLOCKS_DEFERRED_OPEN_NOTIFICATION));
 217 }
 218
 219 /****************************************************************************
 220  Set up an oplock break message.
 221 ****************************************************************************/
 222
 223 static char *new_break_message_smb1(TALLOC_CTX *mem_ctx,
 224                                    files_struct *fsp, int cmd)
 225 {
 226         char *result = talloc_array(mem_ctx, char, smb_size + 8*2 + 0);
 227
 228         if (result == NULL) {
 229                 DEBUG(0, ("talloc failed\n"));
 230                 return NULL;
 231         }
 232
 233         memset(result,'\0',smb_size);
 234         srv_set_message(result,8,0,true);
 235         SCVAL(result,smb_com,SMBlockingX);
 236         SSVAL(result,smb_tid,fsp->conn->cnum);
 237         SSVAL(result,smb_pid,0xFFFF);
 238         SSVAL(result,smb_uid,0);
 239         SSVAL(result,smb_mid,0xFFFF);
 240         SCVAL(result,smb_vwv0,0xFF);
 241         SSVAL(result,smb_vwv2,fsp->fnum);
 242         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 243         SCVAL(result,smb_vwv3+1,cmd);
 244         return result;
 245 }
 246
 247 /****************************************************************************
 248  Function to do the waiting before sending a local break.
 249 ****************************************************************************/
 250
 251 static void wait_before_sending_break(void)
 252 {
 253         long wait_time = (long)lp_oplock_break_wait_time();
 254
 255         if (wait_time) {
 256                 smb_msleep(wait_time);
 257         }
 258 }
 259
 260 /****************************************************************************
 261  Ensure that we have a valid oplock.
 262 ****************************************************************************/
 263
 264 static files_struct *initial_break_processing(
 265         struct smbd_server_connection *sconn, struct file_id id,
 266         unsigned long file_id)
 267 {
 268         files_struct *fsp = NULL;
 269
 270         if( DEBUGLVL( 3 ) ) {
 271                 dbgtext( "initial_break_processing: called for %s/%u\n",
 272                          file_id_string_tos(&id), (int)file_id);
 273                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 274                         exclusive_oplocks_open, level_II_oplocks_open );
 275         }
 276
 277         /*
 278          * We need to search the file open table for the
 279          * entry containing this dev and inode, and ensure
 280          * we have an oplock on it.
 281          */
 282
 283         fsp = file_find_dif(sconn, id, file_id);
 284
 285         if(fsp == NULL) {
 286                 /* The file could have been closed in the meantime - return success. */
 287                 if( DEBUGLVL( 3 ) ) {
 288                         dbgtext( "initial_break_processing: cannot find open file with " );
 289                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 290                         dbgtext( "allowing break to succeed.\n" );
 291                 }
 292                 return NULL;
 293         }
 294
 295         /* Ensure we have an oplock on the file */
 296
 297         /*
 298          * There is a potential race condition in that an oplock could
 299          * have been broken due to another udp request, and yet there are
 300          * still oplock break messages being sent in the udp message
 301          * queue for this file. So return true if we don't have an oplock,
 302          * as we may have just freed it.
 303          */
 304
 305         if(fsp->oplock_type == NO_OPLOCK) {
 306                 if( DEBUGLVL( 3 ) ) {
 307                         dbgtext( "initial_break_processing: file %s ",
 308                                  fsp_str_dbg(fsp));
 309                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 310                                  file_id_string_tos(&id), fsp->fh->gen_id );
 311                         dbgtext( "Allowing break to succeed regardless.\n" );
 312                 }
 313                 return NULL;
 314         }
 315
 316         return fsp;
 317 }
 318
 319 static void oplock_timeout_handler(struct event_context *ctx,
 320                                    struct timed_event *te,
 321                                    struct timeval now,
 322                                    void *private_data)
 323 {
 324         files_struct *fsp = (files_struct *)private_data;
 325
 326         /* Remove the timed event handler. */
 327         TALLOC_FREE(fsp->oplock_timeout);
 328         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 329                   fsp_str_dbg(fsp)));
 330         remove_oplock(fsp);
 331         reply_to_oplock_break_requests(fsp);
 332 }
 333
 334 /*******************************************************************
 335  Add a timeout handler waiting for the client reply.
 336 *******************************************************************/
 337
 338 static void add_oplock_timeout_handler(files_struct *fsp)
 339 {
 340         /*
 341          * If kernel oplocks already notifies smbds when an oplock break times
 342          * out, just return.
 343          */
 344         if (koplocks &&
 345             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 346                 return;
 347         }
 348
 349         if (fsp->oplock_timeout != NULL) {
 350                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 351                           "around\n"));
 352         }
 353
 354         fsp->oplock_timeout =
 355                 tevent_add_timer(fsp->conn->sconn->ev_ctx, fsp,
 356                                  timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 357                                  oplock_timeout_handler, fsp);
 358
 359         if (fsp->oplock_timeout == NULL) {
 360                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 361         }
 362 }
 363
 364 static void send_break_message_smb1(files_struct *fsp, int level)
 365 {
 366         char *break_msg = new_break_message_smb1(talloc_tos(),
 367                                         fsp,
 368                                         level);
 369         if (break_msg == NULL) {
 370                 exit_server("Could not talloc break_msg\n");
 371         }
 372
 373         show_msg(break_msg);
 374         if (!srv_send_smb(fsp->conn->sconn,
 375                         break_msg, false, 0,
 376                         IS_CONN_ENCRYPTED(fsp->conn),
 377                         NULL)) {
 378                 exit_server_cleanly("send_break_message_smb1: "
 379                         "srv_send_smb failed.");
 380         }
 381
 382         TALLOC_FREE(break_msg);
 383 }
 384
 385 void break_level2_to_none_async(files_struct *fsp)
 386 {
 387         struct smbd_server_connection *sconn = fsp->conn->sconn;
 388
 389         if (fsp->oplock_type == NO_OPLOCK) {
 390                 /* We already got a "break to none" message and we've handled
 391                  * it.  just ignore. */
 392                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 393                           "broken to none, ignoring.\n"));
 394                 return;
 395         }
 396
 397         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 398                 /* Don't tell the client, just downgrade. */
 399                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 400                           "downgrading fake level 2 oplock.\n"));
 401                 remove_oplock(fsp);
 402                 return;
 403         }
 404
 405         /* Ensure we're really at level2 state. */
 406         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 407
 408         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 409                   "to none message for fid %d, file %s\n", fsp->fnum,
 410                   fsp_str_dbg(fsp)));
 411
 412         /* Now send a break to none message to our client. */
 413         if (sconn->using_smb2) {
 414                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 415         } else {
 416                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 417         }
 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 case of a write triggering a break to none
 425  message on a level2 oplock.
 426  When we get this message we may be in any of three states :
 427  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 428  the client for LEVEL2.
 429 *******************************************************************/
 430
 431 static void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 432                                                       void *private_data,
 433                                                       uint32_t msg_type,
 434                                                       struct server_id src,
 435                                                       DATA_BLOB *data)
 436 {
 437         struct share_mode_entry msg;
 438         files_struct *fsp;
 439         struct smbd_server_connection *sconn =
 440                 talloc_get_type_abort(private_data,
 441                 struct smbd_server_connection);
 442
 443         if (data->data == NULL) {
 444                 DEBUG(0, ("Got NULL buffer\n"));
 445                 return;
 446         }
 447
 448         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 449                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 450                 return;
 451         }
 452
 453         /* De-linearize incoming message. */
 454         message_to_share_mode_entry(&msg, (char *)data->data);
 455
 456         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 457                    "%s/%llu\n", server_id_str(talloc_tos(), &src),
 458                    file_id_string_tos(&msg.id),
 459                    (unsigned long long)msg.share_file_id));
 460
 461         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 462
 463         if (fsp == NULL) {
 464                 /* We hit a race here. Break messages are sent, and before we
 465                  * get to process this message, we have closed the file.
 466                  * No need to reply as this is an async message. */
 467                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 468                 return;
 469         }
 470
 471         break_level2_to_none_async(fsp);
 472 }
 473
 474 /*******************************************************************
 475  This handles the generic oplock break message from another smbd.
 476 *******************************************************************/
 477
 478 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 479                                          void *private_data,
 480                                          uint32_t msg_type,
 481                                          struct server_id src,
 482                                          DATA_BLOB *data)
 483 {
 484         struct share_mode_entry msg;
 485         files_struct *fsp;
 486         bool break_to_level2 = False;
 487         struct smbd_server_connection *sconn =
 488                 talloc_get_type_abort(private_data,
 489                 struct smbd_server_connection);
 490
 491         if (data->data == NULL) {
 492                 DEBUG(0, ("Got NULL buffer\n"));
 493                 return;
 494         }
 495
 496         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 497                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 498                 return;
 499         }
 500
 501         /* De-linearize incoming message. */
 502         message_to_share_mode_entry(&msg, (char *)data->data);
 503
 504         DEBUG(10, ("Got oplock break message from pid %s: %s/%llu\n",
 505                    server_id_str(talloc_tos(), &src),
 506                    file_id_string_tos(&msg.id),
 507                    (unsigned long long)msg.share_file_id));
 508
 509         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 510
 511         if (fsp == NULL) {
 512                 /* We hit a race here. Break messages are sent, and before we
 513                  * get to process this message, we have closed the file. Reply
 514                  * with 'ok, oplock broken' */
 515                 DEBUG(3, ("Did not find fsp\n"));
 516
 517                 /* We just send the same message back. */
 518                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 519                                    (uint8 *)data->data,
 520                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 521                 return;
 522         }
 523
 524         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 525                 /* Remember we have to inform the requesting PID when the
 526                  * client replies */
 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                 return;
 532         }
 533
 534         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 535             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 536                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 537                           file_id_string_tos(&fsp->file_id),
 538                           fsp_str_dbg(fsp)));
 539                 /* We just send the same message back. */
 540                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 541                                    (uint8 *)data->data,
 542                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 543                 return;
 544         }
 545
 546         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 547             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 548             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 549             lp_level2_oplocks(SNUM(fsp->conn))) {
 550                 break_to_level2 = True;
 551         }
 552
 553         /* Need to wait before sending a break
 554            message if we sent ourselves this message. */
 555         if (procid_is_me(&src)) {
 556                 wait_before_sending_break();
 557         }
 558
 559         if (sconn->using_smb2) {
 560                 send_break_message_smb2(fsp, break_to_level2 ?
 561                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 562         } else {
 563                 send_break_message_smb1(fsp, break_to_level2 ?
 564                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 565         }
 566
 567         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 568
 569         msg.pid = src;
 570         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 571                      &fsp->pending_break_messages,
 572                      &fsp->num_pending_break_messages);
 573
 574         add_oplock_timeout_handler(fsp);
 575 }
 576
 577 /*******************************************************************
 578  This handles the kernel oplock break message.
 579 *******************************************************************/
 580
 581 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 582                                         void *private_data,
 583                                         uint32_t msg_type,
 584                                         struct server_id src,
 585                                         DATA_BLOB *data)
 586 {
 587         struct file_id id;
 588         unsigned long file_id;
 589         files_struct *fsp;
 590         struct smbd_server_connection *sconn =
 591                 talloc_get_type_abort(private_data,
 592                 struct smbd_server_connection);
 593
 594         if (data->data == NULL) {
 595                 DEBUG(0, ("Got NULL buffer\n"));
 596                 return;
 597         }
 598
 599         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 600                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 601                 return;
 602         }
 603
 604         /* Pull the data from the message. */
 605         pull_file_id_24((char *)data->data, &id);
 606         file_id = (unsigned long)IVAL(data->data, 24);
 607
 608         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 609                    server_id_str(talloc_tos(), &src), file_id_string_tos(&id),
 610                    (unsigned int)file_id));
 611
 612         fsp = initial_break_processing(sconn, id, file_id);
 613
 614         if (fsp == NULL) {
 615                 DEBUG(3, ("Got a kernel oplock break message for a file "
 616                           "I don't know about\n"));
 617                 return;
 618         }
 619
 620         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 621                 /* This is ok, kernel oplocks come in completely async */
 622                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 623                           "break reply\n"));
 624                 return;
 625         }
 626
 627         if (sconn->using_smb2) {
 628                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 629         } else {
 630                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 631         }
 632
 633         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 634
 635         add_oplock_timeout_handler(fsp);
 636 }
 637
 638 void reply_to_oplock_break_requests(files_struct *fsp)
 639 {
 640         int i;
 641
 642         /*
 643          * If kernel oplocks already notifies smbds when oplocks are
 644          * broken/removed, just return.
 645          */
 646         if (koplocks &&
 647             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 648                 return;
 649         }
 650
 651         for (i=0; i<fsp->num_pending_break_messages; i++) {
 652                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 653                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 654
 655                 share_mode_entry_to_message(msg, e);
 656
 657                 messaging_send_buf(fsp->conn->sconn->msg_ctx, e->pid,
 658                                    MSG_SMB_BREAK_RESPONSE,
 659                                    (uint8 *)msg,
 660                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 661         }
 662
 663         SAFE_FREE(fsp->pending_break_messages);
 664         fsp->num_pending_break_messages = 0;
 665         if (fsp->oplock_timeout != NULL) {
 666                 /* Remove the timed event handler. */
 667                 TALLOC_FREE(fsp->oplock_timeout);
 668                 fsp->oplock_timeout = NULL;
 669         }
 670         return;
 671 }
 672
 673 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 674                                           void *private_data,
 675                                           uint32_t msg_type,
 676                                           struct server_id src,
 677                                           DATA_BLOB *data)
 678 {
 679         struct share_mode_entry msg;
 680         struct smbd_server_connection *sconn =
 681                 talloc_get_type_abort(private_data,
 682                 struct smbd_server_connection);
 683
 684         if (data->data == NULL) {
 685                 DEBUG(0, ("Got NULL buffer\n"));
 686                 return;
 687         }
 688
 689         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 690                 DEBUG(0, ("Got invalid msg len %u\n",
 691                           (unsigned int)data->length));
 692                 return;
 693         }
 694
 695         /* De-linearize incoming message. */
 696         message_to_share_mode_entry(&msg, (char *)data->data);
 697
 698         DEBUG(10, ("Got oplock break response from pid %s: %s/%llu mid %llu\n",
 699                    server_id_str(talloc_tos(), &src),
 700                    file_id_string_tos(&msg.id),
 701                    (unsigned long long)msg.share_file_id,
 702                    (unsigned long long)msg.op_mid));
 703
 704         schedule_deferred_open_message_smb(sconn, msg.op_mid);
 705 }
 706
 707 static void process_open_retry_message(struct messaging_context *msg_ctx,
 708                                        void *private_data,
 709                                        uint32_t msg_type,
 710                                        struct server_id src,
 711                                        DATA_BLOB *data)
 712 {
 713         struct share_mode_entry msg;
 714         struct smbd_server_connection *sconn =
 715                 talloc_get_type_abort(private_data,
 716                 struct smbd_server_connection);
 717
 718         if (data->data == NULL) {
 719                 DEBUG(0, ("Got NULL buffer\n"));
 720                 return;
 721         }
 722
 723         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 724                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 725                 return;
 726         }
 727
 728         /* De-linearize incoming message. */
 729         message_to_share_mode_entry(&msg, (char *)data->data);
 730
 731         DEBUG(10, ("Got open retry msg from pid %s: %s mid %llu\n",
 732                    server_id_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 733                    (unsigned long long)msg.op_mid));
 734
 735         schedule_deferred_open_message_smb(sconn, msg.op_mid);
 736 }
 737
 738 struct break_to_none_state {
 739         struct smbd_server_connection *sconn;
 740         struct file_id id;
 741 };
 742 static void do_break_to_none(struct tevent_req *req);
 743
 744 /****************************************************************************
 745  This function is called on any file modification or lock request. If a file
 746  is level 2 oplocked then it must tell all other level 2 holders to break to
 747  none.
 748 ****************************************************************************/
 749
 750 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 751                                               enum level2_contention_type type)
 752 {
 753         struct smbd_server_connection *sconn = fsp->conn->sconn;
 754         struct tevent_req *req;
 755         struct break_to_none_state *state;
 756
 757         /*
 758          * If this file is level II oplocked then we need
 759          * to grab the shared memory lock and inform all
 760          * other files with a level II lock that they need
 761          * to flush their read caches. We keep the lock over
 762          * the shared memory area whilst doing this.
 763          */
 764
 765         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 766                 return;
 767
 768         /*
 769          * When we get here we might have a brlock entry locked. Also
 770          * locking the share mode entry would violate the locking
 771          * order. Breaking level2 oplocks to none is asynchronous
 772          * anyway, so we postpone this into an immediate timed event.
 773          */
 774
 775         state = talloc(sconn, struct break_to_none_state);
 776         if (state == NULL) {
 777                 DEBUG(1, ("talloc failed\n"));
 778                 return;
 779         }
 780         state->sconn = sconn;
 781         state->id = fsp->file_id;
 782
 783         req = tevent_wakeup_send(state, sconn->ev_ctx, timeval_set(0, 0));
 784         if (req == NULL) {
 785                 DEBUG(1, ("tevent_wakeup_send failed\n"));
 786                 TALLOC_FREE(state);
 787                 return;
 788         }
 789         tevent_req_set_callback(req, do_break_to_none, state);
 790         return;
 791 }
 792
 793 static void do_break_to_none(struct tevent_req *req)
 794 {
 795         struct break_to_none_state *state = tevent_req_callback_data(
 796                 req, struct break_to_none_state);
 797         bool ret;
 798         int i;
 799         struct share_mode_lock *lck;
 800
 801         ret = tevent_wakeup_recv(req);
 802         TALLOC_FREE(req);
 803         if (!ret) {
 804                 DEBUG(1, ("tevent_wakeup_recv failed\n"));
 805                 goto done;
 806         }
 807         lck = get_share_mode_lock(talloc_tos(), state->id);
 808         if (lck == NULL) {
 809                 DEBUG(1, ("release_level_2_oplocks_on_change: failed to lock "
 810                           "share mode entry for file %s.\n",
 811                           file_id_string_tos(&state->id)));
 812                 goto done;
 813         }
 814
 815         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 816                   lck->data->num_share_modes ));
 817
 818         for(i = 0; i < lck->data->num_share_modes; i++) {
 819                 struct share_mode_entry *share_entry = &lck->data->share_modes[i];
 820                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 821
 822                 if (!is_valid_share_mode_entry(share_entry)) {
 823                         continue;
 824                 }
 825
 826                 /*
 827                  * As there could have been multiple writes waiting at the
 828                  * lock_share_entry gate we may not be the first to
 829                  * enter. Hence the state of the op_types in the share mode
 830                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 831                  * oplock. It will do no harm to re-send break messages to
 832                  * those smbd's that are still waiting their turn to remove
 833                  * their LEVEL_II state, and also no harm to ignore existing
 834                  * NO_OPLOCK states. JRA.
 835                  */
 836
 837                 DEBUG(10,("release_level_2_oplocks_on_change: "
 838                           "share_entry[%i]->op_type == %d\n",
 839                           i, share_entry->op_type ));
 840
 841                 if (share_entry->op_type == NO_OPLOCK) {
 842                         continue;
 843                 }
 844
 845                 /* Paranoia .... */
 846                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 847                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 848                                  "share mode entry %d is an exlusive "
 849                                  "oplock !\n", i ));
 850                         TALLOC_FREE(lck);
 851                         abort();
 852                 }
 853
 854                 share_mode_entry_to_message(msg, share_entry);
 855
 856                 /*
 857                  * Deal with a race condition when breaking level2
 858                  * oplocks. Don't send all the messages and release
 859                  * the lock, this allows someone else to come in and
 860                  * get a level2 lock before any of the messages are
 861                  * processed, and thus miss getting a break message.
 862                  * Ensure at least one entry (the one we're breaking)
 863                  * is processed immediately under the lock and becomes
 864                  * set as NO_OPLOCK to stop any waiter getting a level2.
 865                  * Bugid #5980.
 866                  */
 867
 868                 if (procid_is_me(&share_entry->pid)) {
 869                         struct files_struct *cur_fsp =
 870                                 initial_break_processing(state->sconn,
 871                                         share_entry->id,
 872                                         share_entry->share_file_id);
 873                         wait_before_sending_break();
 874                         if (cur_fsp != NULL) {
 875                                 break_level2_to_none_async(cur_fsp);
 876                         } else {
 877                                 DEBUG(3, ("release_level_2_oplocks_on_change: "
 878                                 "Did not find fsp, ignoring\n"));
 879                         }
 880                 } else {
 881                         messaging_send_buf(state->sconn->msg_ctx,
 882                                         share_entry->pid,
 883                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 884                                         (uint8 *)msg,
 885                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 886                 }
 887         }
 888
 889         /* We let the message receivers handle removing the oplock state
 890            in the share mode lock db. */
 891
 892         TALLOC_FREE(lck);
 893 done:
 894         TALLOC_FREE(state);
 895         return;
 896 }
 897
 898 void smbd_contend_level2_oplocks_begin(files_struct *fsp,
 899                                   enum level2_contention_type type)
 900 {
 901         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 902                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 903                 return;
 904         }
 905
 906         contend_level2_oplocks_begin_default(fsp, type);
 907 }
 908
 909 void smbd_contend_level2_oplocks_end(files_struct *fsp,
 910                                 enum level2_contention_type type)
 911 {
 912         /* Only kernel oplocks implement this so far */
 913         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 914                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 915         }
 916 }
 917
 918 /****************************************************************************
 919  Linearize a share mode entry struct to an internal oplock break message.
 920 ****************************************************************************/
 921
 922 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 923 {
 924         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 925         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 926         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 927         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 928         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 929         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 930         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 931         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 932         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 933         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 934         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 935         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 936         SIVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET,e->name_hash);
 937         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 938 }
 939
 940 /****************************************************************************
 941  De-linearize an internal oplock break message to a share mode entry struct.
 942 ****************************************************************************/
 943
 944 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 945 {
 946         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 947         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 948         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 949         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 950         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 951         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 952         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 953         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 954         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 955         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 956         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 957         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 958         e->name_hash = IVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET);
 959         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 960 }
 961
 962 /****************************************************************************
 963  Setup oplocks for this process.
 964 ****************************************************************************/
 965
 966 bool init_oplocks(struct smbd_server_connection *sconn)
 967 {
 968         DEBUG(3,("init_oplocks: initializing messages.\n"));
 969
 970         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_REQUEST,
 971                            process_oplock_break_message);
 972         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_ASYNC_LEVEL2_BREAK,
 973                            process_oplock_async_level2_break_message);
 974         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_RESPONSE,
 975                            process_oplock_break_response);
 976         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_KERNEL_BREAK,
 977                            process_kernel_oplock_break);
 978         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_OPEN_RETRY,
 979                            process_open_retry_message);
 980
 981         if (lp_kernel_oplocks()) {
 982 #if HAVE_KERNEL_OPLOCKS_IRIX
 983                 koplocks = irix_init_kernel_oplocks(sconn);
 984 #elif HAVE_KERNEL_OPLOCKS_LINUX
 985                 koplocks = linux_init_kernel_oplocks(sconn);
 986 #elif HAVE_ONEFS
 987 #error Isilon, please check if the NULL context is okay here. Thanks!
 988                 koplocks = onefs_init_kernel_oplocks(sconn);
 989 #endif
 990         }
 991
 992         return True;
 993 }