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
  28 /****************************************************************************
  29  Get the number of current exclusive oplocks.
  30 ****************************************************************************/
  31
  32 int32 get_number_of_exclusive_open_oplocks(void)
  33 {
  34   return exclusive_oplocks_open;
  35 }
  36
  37 /*
  38  * helper function used by the kernel oplock backends to post the break message
  39  */
  40 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  41 {
  42         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  43
  44         /* Put the kernel break info into the message. */
  45         push_file_id_24((char *)msg, &fsp->file_id);
  46         SIVAL(msg,24,fsp->fh->gen_id);
  47
  48         /* Don't need to be root here as we're only ever
  49            sending to ourselves. */
  50
  51         messaging_send_buf(msg_ctx, messaging_server_id(msg_ctx),
  52                            MSG_SMB_KERNEL_BREAK,
  53                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  54 }
  55
  56 /****************************************************************************
  57  Attempt to set an oplock on a file. Succeeds if kernel oplocks are
  58  disabled (just sets flags) and no byte-range locks in the file. Returns True
  59  if oplock set.
  60 ****************************************************************************/
  61
  62 bool set_file_oplock(files_struct *fsp, int oplock_type)
  63 {
  64         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  65                 if (koplocks &&
  66                     !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
  67                         DEBUG(10, ("Refusing level2 oplock, kernel oplocks "
  68                                    "don't support them\n"));
  69                         return false;
  70                 }
  71         }
  72
  73         if ((fsp->oplock_type != NO_OPLOCK) &&
  74             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  75             koplocks &&
  76             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
  77                 return False;
  78         }
  79
  80         fsp->oplock_type = oplock_type;
  81         fsp->sent_oplock_break = NO_BREAK_SENT;
  82         if (oplock_type == LEVEL_II_OPLOCK) {
  83                 level_II_oplocks_open++;
  84         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  85                 exclusive_oplocks_open++;
  86         }
  87
  88         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  89                     "tv_sec = %x, tv_usec = %x\n",
  90                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  91                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  92                  (int)fsp->open_time.tv_usec ));
  93
  94         return True;
  95 }
  96
  97 /****************************************************************************
  98  Attempt to release an oplock on a file. Decrements oplock count.
  99 ****************************************************************************/
 100
 101 void release_file_oplock(files_struct *fsp)
 102 {
 103         if ((fsp->oplock_type != NO_OPLOCK) &&
 104             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 105             koplocks) {
 106                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 107         }
 108
 109         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 110                 level_II_oplocks_open--;
 111         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 112                 exclusive_oplocks_open--;
 113         }
 114
 115         SMB_ASSERT(exclusive_oplocks_open>=0);
 116         SMB_ASSERT(level_II_oplocks_open>=0);
 117
 118         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 119                 /* This doesn't matter for close. */
 120                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 121         } else {
 122                 fsp->oplock_type = NO_OPLOCK;
 123         }
 124         fsp->sent_oplock_break = NO_BREAK_SENT;
 125
 126         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 127         delete_write_cache(fsp);
 128
 129         TALLOC_FREE(fsp->oplock_timeout);
 130 }
 131
 132 /****************************************************************************
 133  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 134 ****************************************************************************/
 135
 136 static void downgrade_file_oplock(files_struct *fsp)
 137 {
 138         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 139                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 140                 return;
 141         }
 142
 143         if (koplocks) {
 144                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 145         }
 146         fsp->oplock_type = LEVEL_II_OPLOCK;
 147         exclusive_oplocks_open--;
 148         level_II_oplocks_open++;
 149         fsp->sent_oplock_break = NO_BREAK_SENT;
 150 }
 151
 152 /****************************************************************************
 153  Remove a file oplock. Copes with level II and exclusive.
 154  Locks then unlocks the share mode lock. Client can decide to go directly
 155  to none even if a "break-to-level II" was sent.
 156 ****************************************************************************/
 157
 158 bool remove_oplock(files_struct *fsp)
 159 {
 160         bool ret;
 161         struct share_mode_lock *lck;
 162
 163         /* Remove the oplock flag from the sharemode. */
 164         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 165                                   NULL);
 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, NULL, NULL,
 192                                   NULL);
 193         if (lck == NULL) {
 194                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 195                          "file %s\n", fsp_str_dbg(fsp)));
 196                 return False;
 197         }
 198         ret = downgrade_share_oplock(lck, fsp);
 199         if (!ret) {
 200                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 201                          "for file %s fnum %d, file_id %s\n",
 202                          fsp_str_dbg(fsp), fsp->fnum,
 203                          file_id_string_tos(&fsp->file_id)));
 204         }
 205
 206         downgrade_file_oplock(fsp);
 207         TALLOC_FREE(lck);
 208         return ret;
 209 }
 210
 211 /*
 212  * Some kernel oplock implementations handle the notification themselves.
 213  */
 214 bool should_notify_deferred_opens()
 215 {
 216         return !(koplocks &&
 217                 (koplocks->flags & KOPLOCKS_DEFERRED_OPEN_NOTIFICATION));
 218 }
 219
 220 /****************************************************************************
 221  Set up an oplock break message.
 222 ****************************************************************************/
 223
 224 static char *new_break_message_smb1(TALLOC_CTX *mem_ctx,
 225                                    files_struct *fsp, int cmd)
 226 {
 227         char *result = talloc_array(mem_ctx, char, smb_size + 8*2 + 0);
 228
 229         if (result == NULL) {
 230                 DEBUG(0, ("talloc failed\n"));
 231                 return NULL;
 232         }
 233
 234         memset(result,'\0',smb_size);
 235         srv_set_message(result,8,0,true);
 236         SCVAL(result,smb_com,SMBlockingX);
 237         SSVAL(result,smb_tid,fsp->conn->cnum);
 238         SSVAL(result,smb_pid,0xFFFF);
 239         SSVAL(result,smb_uid,0);
 240         SSVAL(result,smb_mid,0xFFFF);
 241         SCVAL(result,smb_vwv0,0xFF);
 242         SSVAL(result,smb_vwv2,fsp->fnum);
 243         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 244         SCVAL(result,smb_vwv3+1,cmd);
 245         return result;
 246 }
 247
 248 /****************************************************************************
 249  Function to do the waiting before sending a local break.
 250 ****************************************************************************/
 251
 252 static void wait_before_sending_break(void)
 253 {
 254         long wait_time = (long)lp_oplock_break_wait_time();
 255
 256         if (wait_time) {
 257                 smb_msleep(wait_time);
 258         }
 259 }
 260
 261 /****************************************************************************
 262  Ensure that we have a valid oplock.
 263 ****************************************************************************/
 264
 265 static files_struct *initial_break_processing(
 266         struct smbd_server_connection *sconn, struct file_id id,
 267         unsigned long file_id)
 268 {
 269         files_struct *fsp = NULL;
 270
 271         if( DEBUGLVL( 3 ) ) {
 272                 dbgtext( "initial_break_processing: called for %s/%u\n",
 273                          file_id_string_tos(&id), (int)file_id);
 274                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 275                         exclusive_oplocks_open, level_II_oplocks_open );
 276         }
 277
 278         /*
 279          * We need to search the file open table for the
 280          * entry containing this dev and inode, and ensure
 281          * we have an oplock on it.
 282          */
 283
 284         fsp = file_find_dif(sconn, id, file_id);
 285
 286         if(fsp == NULL) {
 287                 /* The file could have been closed in the meantime - return success. */
 288                 if( DEBUGLVL( 3 ) ) {
 289                         dbgtext( "initial_break_processing: cannot find open file with " );
 290                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 291                         dbgtext( "allowing break to succeed.\n" );
 292                 }
 293                 return NULL;
 294         }
 295
 296         /* Ensure we have an oplock on the file */
 297
 298         /*
 299          * There is a potential race condition in that an oplock could
 300          * have been broken due to another udp request, and yet there are
 301          * still oplock break messages being sent in the udp message
 302          * queue for this file. So return true if we don't have an oplock,
 303          * as we may have just freed it.
 304          */
 305
 306         if(fsp->oplock_type == NO_OPLOCK) {
 307                 if( DEBUGLVL( 3 ) ) {
 308                         dbgtext( "initial_break_processing: file %s ",
 309                                  fsp_str_dbg(fsp));
 310                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 311                                  file_id_string_tos(&id), fsp->fh->gen_id );
 312                         dbgtext( "Allowing break to succeed regardless.\n" );
 313                 }
 314                 return NULL;
 315         }
 316
 317         return fsp;
 318 }
 319
 320 static void oplock_timeout_handler(struct event_context *ctx,
 321                                    struct timed_event *te,
 322                                    struct timeval now,
 323                                    void *private_data)
 324 {
 325         files_struct *fsp = (files_struct *)private_data;
 326
 327         /* Remove the timed event handler. */
 328         TALLOC_FREE(fsp->oplock_timeout);
 329         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 330                   fsp_str_dbg(fsp)));
 331         remove_oplock(fsp);
 332         reply_to_oplock_break_requests(fsp);
 333 }
 334
 335 /*******************************************************************
 336  Add a timeout handler waiting for the client reply.
 337 *******************************************************************/
 338
 339 static void add_oplock_timeout_handler(files_struct *fsp)
 340 {
 341         /*
 342          * If kernel oplocks already notifies smbds when an oplock break times
 343          * out, just return.
 344          */
 345         if (koplocks &&
 346             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 347                 return;
 348         }
 349
 350         if (fsp->oplock_timeout != NULL) {
 351                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 352                           "around\n"));
 353         }
 354
 355         fsp->oplock_timeout =
 356                 event_add_timed(server_event_context(), fsp,
 357                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 358                                 oplock_timeout_handler, fsp);
 359
 360         if (fsp->oplock_timeout == NULL) {
 361                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 362         }
 363 }
 364
 365 static void send_break_message_smb1(files_struct *fsp, int level)
 366 {
 367         char *break_msg = new_break_message_smb1(talloc_tos(),
 368                                         fsp,
 369                                         level);
 370         if (break_msg == NULL) {
 371                 exit_server("Could not talloc break_msg\n");
 372         }
 373
 374         show_msg(break_msg);
 375         if (!srv_send_smb(fsp->conn->sconn,
 376                         break_msg, false, 0,
 377                         IS_CONN_ENCRYPTED(fsp->conn),
 378                         NULL)) {
 379                 exit_server_cleanly("send_break_message_smb1: "
 380                         "srv_send_smb failed.");
 381         }
 382
 383         TALLOC_FREE(break_msg);
 384 }
 385
 386 void break_level2_to_none_async(files_struct *fsp)
 387 {
 388         struct smbd_server_connection *sconn = fsp->conn->sconn;
 389
 390         if (fsp->oplock_type == NO_OPLOCK) {
 391                 /* We already got a "break to none" message and we've handled
 392                  * it.  just ignore. */
 393                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 394                           "broken to none, ignoring.\n"));
 395                 return;
 396         }
 397
 398         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 399                 /* Don't tell the client, just downgrade. */
 400                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 401                           "downgrading fake level 2 oplock.\n"));
 402                 remove_oplock(fsp);
 403                 return;
 404         }
 405
 406         /* Ensure we're really at level2 state. */
 407         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 408
 409         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 410                   "to none message for fid %d, file %s\n", fsp->fnum,
 411                   fsp_str_dbg(fsp)));
 412
 413         /* Now send a break to none message to our client. */
 414         if (sconn->using_smb2) {
 415                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 416         } else {
 417                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 418         }
 419
 420         /* Async level2 request, don't send a reply, just remove the oplock. */
 421         remove_oplock(fsp);
 422 }
 423
 424 /*******************************************************************
 425  This handles the case of a write triggering a break to none
 426  message on a level2 oplock.
 427  When we get this message we may be in any of three states :
 428  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 429  the client for LEVEL2.
 430 *******************************************************************/
 431
 432 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 433                                                       void *private_data,
 434                                                       uint32_t msg_type,
 435                                                       struct server_id src,
 436                                                       DATA_BLOB *data)
 437 {
 438         struct smbd_server_connection *sconn;
 439         struct share_mode_entry msg;
 440         files_struct *fsp;
 441
 442         if (data->data == NULL) {
 443                 DEBUG(0, ("Got NULL buffer\n"));
 444                 return;
 445         }
 446
 447         sconn = msg_ctx_to_sconn(msg_ctx);
 448         if (sconn == NULL) {
 449                 DEBUG(1, ("could not find sconn\n"));
 450                 return;
 451         }
 452
 453         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 454                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 455                 return;
 456         }
 457
 458         /* De-linearize incoming message. */
 459         message_to_share_mode_entry(&msg, (char *)data->data);
 460
 461         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 462                    "%s/%lu\n", procid_str(talloc_tos(), &src),
 463                    file_id_string_tos(&msg.id), msg.share_file_id));
 464
 465         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 466
 467         if (fsp == NULL) {
 468                 /* We hit a race here. Break messages are sent, and before we
 469                  * get to process this message, we have closed the file.
 470                  * No need to reply as this is an async message. */
 471                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 472                 return;
 473         }
 474
 475         break_level2_to_none_async(fsp);
 476 }
 477
 478 /*******************************************************************
 479  This handles the generic oplock break message from another smbd.
 480 *******************************************************************/
 481
 482 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 483                                          void *private_data,
 484                                          uint32_t msg_type,
 485                                          struct server_id src,
 486                                          DATA_BLOB *data)
 487 {
 488         struct smbd_server_connection *sconn;
 489         struct share_mode_entry msg;
 490         files_struct *fsp;
 491         bool break_to_level2 = False;
 492
 493         if (data->data == NULL) {
 494                 DEBUG(0, ("Got NULL buffer\n"));
 495                 return;
 496         }
 497
 498         sconn = msg_ctx_to_sconn(msg_ctx);
 499         if (sconn == NULL) {
 500                 DEBUG(1, ("could not find sconn\n"));
 501                 return;
 502         }
 503
 504         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 505                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 506                 return;
 507         }
 508
 509         /* De-linearize incoming message. */
 510         message_to_share_mode_entry(&msg, (char *)data->data);
 511
 512         DEBUG(10, ("Got oplock break message from pid %s: %s/%lu\n",
 513                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 514                    msg.share_file_id));
 515
 516         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 517
 518         if (fsp == NULL) {
 519                 /* We hit a race here. Break messages are sent, and before we
 520                  * get to process this message, we have closed the file. Reply
 521                  * with 'ok, oplock broken' */
 522                 DEBUG(3, ("Did not find fsp\n"));
 523
 524                 /* We just send the same message back. */
 525                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 526                                    (uint8 *)data->data,
 527                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 528                 return;
 529         }
 530
 531         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 532                 /* Remember we have to inform the requesting PID when the
 533                  * client replies */
 534                 msg.pid = src;
 535                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 536                              &fsp->pending_break_messages,
 537                              &fsp->num_pending_break_messages);
 538                 return;
 539         }
 540
 541         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 542             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 543                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 544                           file_id_string_tos(&fsp->file_id),
 545                           fsp_str_dbg(fsp)));
 546                 /* We just send the same message back. */
 547                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 548                                    (uint8 *)data->data,
 549                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 550                 return;
 551         }
 552
 553         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 554             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 555             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 556             lp_level2_oplocks(SNUM(fsp->conn))) {
 557                 break_to_level2 = True;
 558         }
 559
 560         /* Need to wait before sending a break
 561            message if we sent ourselves this message. */
 562         if (procid_is_me(&src)) {
 563                 wait_before_sending_break();
 564         }
 565
 566         if (sconn->using_smb2) {
 567                 send_break_message_smb2(fsp, break_to_level2 ?
 568                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 569         } else {
 570                 send_break_message_smb1(fsp, break_to_level2 ?
 571                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 572         }
 573
 574         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 575
 576         msg.pid = src;
 577         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 578                      &fsp->pending_break_messages,
 579                      &fsp->num_pending_break_messages);
 580
 581         add_oplock_timeout_handler(fsp);
 582 }
 583
 584 /*******************************************************************
 585  This handles the kernel oplock break message.
 586 *******************************************************************/
 587
 588 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 589                                         void *private_data,
 590                                         uint32_t msg_type,
 591                                         struct server_id src,
 592                                         DATA_BLOB *data)
 593 {
 594         struct smbd_server_connection *sconn;
 595         struct file_id id;
 596         unsigned long file_id;
 597         files_struct *fsp;
 598
 599         if (data->data == NULL) {
 600                 DEBUG(0, ("Got NULL buffer\n"));
 601                 return;
 602         }
 603
 604         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 605                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 606                 return;
 607         }
 608
 609         sconn = msg_ctx_to_sconn(msg_ctx);
 610         if (sconn == NULL) {
 611                 DEBUG(1, ("could not find sconn\n"));
 612                 return;
 613         }
 614
 615         /* Pull the data from the message. */
 616         pull_file_id_24((char *)data->data, &id);
 617         file_id = (unsigned long)IVAL(data->data, 24);
 618
 619         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 620                    procid_str(talloc_tos(), &src), file_id_string_tos(&id),
 621                    (unsigned int)file_id));
 622
 623         fsp = initial_break_processing(sconn, id, file_id);
 624
 625         if (fsp == NULL) {
 626                 DEBUG(3, ("Got a kernel oplock break message for a file "
 627                           "I don't know about\n"));
 628                 return;
 629         }
 630
 631         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 632                 /* This is ok, kernel oplocks come in completely async */
 633                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 634                           "break reply\n"));
 635                 return;
 636         }
 637
 638         if (sconn->using_smb2) {
 639                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 640         } else {
 641                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 642         }
 643
 644         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 645
 646         add_oplock_timeout_handler(fsp);
 647 }
 648
 649 void reply_to_oplock_break_requests(files_struct *fsp)
 650 {
 651         int i;
 652
 653         /*
 654          * If kernel oplocks already notifies smbds when oplocks are
 655          * broken/removed, just return.
 656          */
 657         if (koplocks &&
 658             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 659                 return;
 660         }
 661
 662         for (i=0; i<fsp->num_pending_break_messages; i++) {
 663                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 664                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 665
 666                 share_mode_entry_to_message(msg, e);
 667
 668                 messaging_send_buf(fsp->conn->sconn->msg_ctx, e->pid,
 669                                    MSG_SMB_BREAK_RESPONSE,
 670                                    (uint8 *)msg,
 671                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 672         }
 673
 674         SAFE_FREE(fsp->pending_break_messages);
 675         fsp->num_pending_break_messages = 0;
 676         if (fsp->oplock_timeout != NULL) {
 677                 /* Remove the timed event handler. */
 678                 TALLOC_FREE(fsp->oplock_timeout);
 679                 fsp->oplock_timeout = NULL;
 680         }
 681         return;
 682 }
 683
 684 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 685                                           void *private_data,
 686                                           uint32_t msg_type,
 687                                           struct server_id src,
 688                                           DATA_BLOB *data)
 689 {
 690         struct share_mode_entry msg;
 691
 692         if (data->data == NULL) {
 693                 DEBUG(0, ("Got NULL buffer\n"));
 694                 return;
 695         }
 696
 697         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 698                 DEBUG(0, ("Got invalid msg len %u\n",
 699                           (unsigned int)data->length));
 700                 return;
 701         }
 702
 703         /* De-linearize incoming message. */
 704         message_to_share_mode_entry(&msg, (char *)data->data);
 705
 706         DEBUG(10, ("Got oplock break response from pid %s: %s/%lu mid %llu\n",
 707                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 708                    msg.share_file_id, (unsigned long long)msg.op_mid));
 709
 710         schedule_deferred_open_message_smb(msg.op_mid);
 711 }
 712
 713 static void process_open_retry_message(struct messaging_context *msg_ctx,
 714                                        void *private_data,
 715                                        uint32_t msg_type,
 716                                        struct server_id src,
 717                                        DATA_BLOB *data)
 718 {
 719         struct share_mode_entry msg;
 720
 721         if (data->data == NULL) {
 722                 DEBUG(0, ("Got NULL buffer\n"));
 723                 return;
 724         }
 725
 726         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 727                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 728                 return;
 729         }
 730
 731         /* De-linearize incoming message. */
 732         message_to_share_mode_entry(&msg, (char *)data->data);
 733
 734         DEBUG(10, ("Got open retry msg from pid %s: %s mid %llu\n",
 735                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 736                    (unsigned long long)msg.op_mid));
 737
 738         schedule_deferred_open_message_smb(msg.op_mid);
 739 }
 740
 741 /****************************************************************************
 742  This function is called on any file modification or lock request. If a file
 743  is level 2 oplocked then it must tell all other level 2 holders to break to
 744  none.
 745 ****************************************************************************/
 746
 747 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 748                                               enum level2_contention_type type)
 749 {
 750         int i;
 751         struct share_mode_lock *lck;
 752
 753         /*
 754          * If this file is level II oplocked then we need
 755          * to grab the shared memory lock and inform all
 756          * other files with a level II lock that they need
 757          * to flush their read caches. We keep the lock over
 758          * the shared memory area whilst doing this.
 759          */
 760
 761         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 762                 return;
 763
 764         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 765                                   NULL);
 766         if (lck == NULL) {
 767                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 768                          "share mode entry for file %s.\n", fsp_str_dbg(fsp)));
 769                 return;
 770         }
 771
 772         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 773                   lck->num_share_modes ));
 774
 775         for(i = 0; i < lck->num_share_modes; i++) {
 776                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 777                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 778
 779                 if (!is_valid_share_mode_entry(share_entry)) {
 780                         continue;
 781                 }
 782
 783                 /*
 784                  * As there could have been multiple writes waiting at the
 785                  * lock_share_entry gate we may not be the first to
 786                  * enter. Hence the state of the op_types in the share mode
 787                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 788                  * oplock. It will do no harm to re-send break messages to
 789                  * those smbd's that are still waiting their turn to remove
 790                  * their LEVEL_II state, and also no harm to ignore existing
 791                  * NO_OPLOCK states. JRA.
 792                  */
 793
 794                 DEBUG(10,("release_level_2_oplocks_on_change: "
 795                           "share_entry[%i]->op_type == %d\n",
 796                           i, share_entry->op_type ));
 797
 798                 if (share_entry->op_type == NO_OPLOCK) {
 799                         continue;
 800                 }
 801
 802                 /* Paranoia .... */
 803                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 804                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 805                                  "share mode entry %d is an exlusive "
 806                                  "oplock !\n", i ));
 807                         TALLOC_FREE(lck);
 808                         abort();
 809                 }
 810
 811                 share_mode_entry_to_message(msg, share_entry);
 812
 813                 /*
 814                  * Deal with a race condition when breaking level2
 815                  * oplocks. Don't send all the messages and release
 816                  * the lock, this allows someone else to come in and
 817                  * get a level2 lock before any of the messages are
 818                  * processed, and thus miss getting a break message.
 819                  * Ensure at least one entry (the one we're breaking)
 820                  * is processed immediately under the lock and becomes
 821                  * set as NO_OPLOCK to stop any waiter getting a level2.
 822                  * Bugid #5980.
 823                  */
 824
 825                 if (procid_is_me(&share_entry->pid)) {
 826                         struct files_struct *cur_fsp =
 827                                 initial_break_processing(fsp->conn->sconn,
 828                                         share_entry->id,
 829                                         share_entry->share_file_id);
 830                         wait_before_sending_break();
 831                         if (cur_fsp != NULL) {
 832                                 break_level2_to_none_async(cur_fsp);
 833                         } else {
 834                                 DEBUG(3, ("release_level_2_oplocks_on_change: "
 835                                 "Did not find fsp, ignoring\n"));
 836                         }
 837                 } else {
 838                         messaging_send_buf(fsp->conn->sconn->msg_ctx,
 839                                         share_entry->pid,
 840                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 841                                         (uint8 *)msg,
 842                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 843                 }
 844         }
 845
 846         /* We let the message receivers handle removing the oplock state
 847            in the share mode lock db. */
 848
 849         TALLOC_FREE(lck);
 850 }
 851
 852 void contend_level2_oplocks_begin(files_struct *fsp,
 853                                   enum level2_contention_type type)
 854 {
 855         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 856                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 857                 return;
 858         }
 859
 860         contend_level2_oplocks_begin_default(fsp, type);
 861 }
 862
 863 void contend_level2_oplocks_end(files_struct *fsp,
 864                                 enum level2_contention_type type)
 865 {
 866         /* Only kernel oplocks implement this so far */
 867         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 868                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 869         }
 870 }
 871
 872 /****************************************************************************
 873  Linearize a share mode entry struct to an internal oplock break message.
 874 ****************************************************************************/
 875
 876 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 877 {
 878         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 879         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 880         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 881         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 882         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 883         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 884         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 885         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 886         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 887         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 888         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 889         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 890         SIVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET,e->name_hash);
 891         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 892 }
 893
 894 /****************************************************************************
 895  De-linearize an internal oplock break message to a share mode entry struct.
 896 ****************************************************************************/
 897
 898 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 899 {
 900         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 901         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 902         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 903         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 904         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 905         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 906         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 907         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 908         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 909         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 910         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 911         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 912         e->name_hash = IVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET);
 913         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 914 }
 915
 916 /****************************************************************************
 917  Setup oplocks for this process.
 918 ****************************************************************************/
 919
 920 bool init_oplocks(struct messaging_context *msg_ctx)
 921 {
 922         DEBUG(3,("init_oplocks: initializing messages.\n"));
 923
 924         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 925                            process_oplock_break_message);
 926         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 927                            process_oplock_async_level2_break_message);
 928         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 929                            process_oplock_break_response);
 930         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 931                            process_kernel_oplock_break);
 932         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 933                            process_open_retry_message);
 934
 935         if (lp_kernel_oplocks()) {
 936 #if HAVE_KERNEL_OPLOCKS_IRIX
 937                 koplocks = irix_init_kernel_oplocks(NULL);
 938 #elif HAVE_KERNEL_OPLOCKS_LINUX
 939                 koplocks = linux_init_kernel_oplocks(NULL);
 940 #elif HAVE_ONEFS
 941 #error Isilon, please check if the NULL context is okay here. Thanks!
 942                 koplocks = onefs_init_kernel_oplocks(NULL);
 943 #endif
 944         }
 945
 946         return True;
 947 }