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 #include "librpc/gen_ndr/messaging.h"
  26
  27 /****************************************************************************
  28  Get the number of current exclusive oplocks.
  29 ****************************************************************************/
  30
  31 int32 get_number_of_exclusive_open_oplocks(void)
  32 {
  33   return exclusive_oplocks_open;
  34 }
  35
  36 /*
  37  * helper function used by the kernel oplock backends to post the break message
  38  */
  39 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  40 {
  41         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  42
  43         /* Put the kernel break info into the message. */
  44         push_file_id_24((char *)msg, &fsp->file_id);
  45         SIVAL(msg,24,fsp->fh->gen_id);
  46
  47         /* Don't need to be root here as we're only ever
  48            sending to ourselves. */
  49
  50         messaging_send_buf(msg_ctx, procid_self(),
  51                            MSG_SMB_KERNEL_BREAK,
  52                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  53 }
  54
  55 /****************************************************************************
  56  Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
  57  disabled (just sets flags). Returns True if oplock set.
  58 ****************************************************************************/
  59
  60 bool set_file_oplock(files_struct *fsp, int oplock_type)
  61 {
  62         if ((fsp->oplock_type == LEVEL_II_OPLOCK)
  63             && koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
  64                 DEBUG(10, ("Refusing level2 oplock, kernel oplocks don't "
  65                            "support them\n"));
  66                 return false;
  67         }
  68         if ((fsp->oplock_type != NO_OPLOCK) &&
  69             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  70             koplocks &&
  71             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
  72                 return False;
  73         }
  74
  75         fsp->oplock_type = oplock_type;
  76         fsp->sent_oplock_break = NO_BREAK_SENT;
  77         if (oplock_type == LEVEL_II_OPLOCK) {
  78                 level_II_oplocks_open++;
  79         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  80                 exclusive_oplocks_open++;
  81         }
  82
  83         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  84                     "tv_sec = %x, tv_usec = %x\n",
  85                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  86                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  87                  (int)fsp->open_time.tv_usec ));
  88
  89         return True;
  90 }
  91
  92 /****************************************************************************
  93  Attempt to release an oplock on a file. Decrements oplock count.
  94 ****************************************************************************/
  95
  96 void release_file_oplock(files_struct *fsp)
  97 {
  98         if ((fsp->oplock_type != NO_OPLOCK) &&
  99             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 100             koplocks) {
 101                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 102         }
 103
 104         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 105                 level_II_oplocks_open--;
 106         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 107                 exclusive_oplocks_open--;
 108         }
 109
 110         SMB_ASSERT(exclusive_oplocks_open>=0);
 111         SMB_ASSERT(level_II_oplocks_open>=0);
 112
 113         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 114                 /* This doesn't matter for close. */
 115                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 116         } else {
 117                 fsp->oplock_type = NO_OPLOCK;
 118         }
 119         fsp->sent_oplock_break = NO_BREAK_SENT;
 120
 121         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 122
 123         TALLOC_FREE(fsp->oplock_timeout);
 124 }
 125
 126 /****************************************************************************
 127  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 128 ****************************************************************************/
 129
 130 static void downgrade_file_oplock(files_struct *fsp)
 131 {
 132         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 133                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 134                 return;
 135         }
 136
 137         if (koplocks) {
 138                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 139         }
 140         fsp->oplock_type = LEVEL_II_OPLOCK;
 141         exclusive_oplocks_open--;
 142         level_II_oplocks_open++;
 143         fsp->sent_oplock_break = NO_BREAK_SENT;
 144 }
 145
 146 /****************************************************************************
 147  Remove a file oplock. Copes with level II and exclusive.
 148  Locks then unlocks the share mode lock. Client can decide to go directly
 149  to none even if a "break-to-level II" was sent.
 150 ****************************************************************************/
 151
 152 bool remove_oplock(files_struct *fsp)
 153 {
 154         bool ret;
 155         struct share_mode_lock *lck;
 156
 157         /* Remove the oplock flag from the sharemode. */
 158         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 159                                   NULL);
 160         if (lck == NULL) {
 161                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 162                          "file %s\n", fsp_str_dbg(fsp)));
 163                 return False;
 164         }
 165         ret = remove_share_oplock(lck, fsp);
 166         if (!ret) {
 167                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 168                          "file %s fnum %d, %s\n",
 169                          fsp_str_dbg(fsp), fsp->fnum,
 170                          file_id_string_tos(&fsp->file_id)));
 171         }
 172         release_file_oplock(fsp);
 173         TALLOC_FREE(lck);
 174         return ret;
 175 }
 176
 177 /*
 178  * Deal with a reply when a break-to-level II was sent.
 179  */
 180 bool downgrade_oplock(files_struct *fsp)
 181 {
 182         bool ret;
 183         struct share_mode_lock *lck;
 184
 185         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 186                                   NULL);
 187         if (lck == NULL) {
 188                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 189                          "file %s\n", fsp_str_dbg(fsp)));
 190                 return False;
 191         }
 192         ret = downgrade_share_oplock(lck, fsp);
 193         if (!ret) {
 194                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 195                          "for file %s fnum %d, file_id %s\n",
 196                          fsp_str_dbg(fsp), fsp->fnum,
 197                          file_id_string_tos(&fsp->file_id)));
 198         }
 199
 200         downgrade_file_oplock(fsp);
 201         TALLOC_FREE(lck);
 202         return ret;
 203 }
 204
 205 /*
 206  * Some kernel oplock implementations handle the notification themselves.
 207  */
 208 bool should_notify_deferred_opens()
 209 {
 210         return !(koplocks &&
 211                 (koplocks->flags & KOPLOCKS_DEFERRED_OPEN_NOTIFICATION));
 212 }
 213
 214 /****************************************************************************
 215  Set up an oplock break message.
 216 ****************************************************************************/
 217
 218 static char *new_break_message_smb1(TALLOC_CTX *mem_ctx,
 219                                    files_struct *fsp, int cmd)
 220 {
 221         char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
 222
 223         if (result == NULL) {
 224                 DEBUG(0, ("talloc failed\n"));
 225                 return NULL;
 226         }
 227
 228         memset(result,'\0',smb_size);
 229         srv_set_message(result,8,0,true);
 230         SCVAL(result,smb_com,SMBlockingX);
 231         SSVAL(result,smb_tid,fsp->conn->cnum);
 232         SSVAL(result,smb_pid,0xFFFF);
 233         SSVAL(result,smb_uid,0);
 234         SSVAL(result,smb_mid,0xFFFF);
 235         SCVAL(result,smb_vwv0,0xFF);
 236         SSVAL(result,smb_vwv2,fsp->fnum);
 237         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 238         SCVAL(result,smb_vwv3+1,cmd);
 239         return result;
 240 }
 241
 242 /****************************************************************************
 243  Function to do the waiting before sending a local break.
 244 ****************************************************************************/
 245
 246 static void wait_before_sending_break(void)
 247 {
 248         long wait_time = (long)lp_oplock_break_wait_time();
 249
 250         if (wait_time) {
 251                 smb_msleep(wait_time);
 252         }
 253 }
 254
 255 /****************************************************************************
 256  Ensure that we have a valid oplock.
 257 ****************************************************************************/
 258
 259 static files_struct *initial_break_processing(struct file_id id, unsigned long file_id)
 260 {
 261         files_struct *fsp = NULL;
 262
 263         if( DEBUGLVL( 3 ) ) {
 264                 dbgtext( "initial_break_processing: called for %s/%u\n",
 265                          file_id_string_tos(&id), (int)file_id);
 266                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 267                         exclusive_oplocks_open, level_II_oplocks_open );
 268         }
 269
 270         /*
 271          * We need to search the file open table for the
 272          * entry containing this dev and inode, and ensure
 273          * we have an oplock on it.
 274          */
 275
 276         fsp = file_find_dif(id, file_id);
 277
 278         if(fsp == NULL) {
 279                 /* The file could have been closed in the meantime - return success. */
 280                 if( DEBUGLVL( 3 ) ) {
 281                         dbgtext( "initial_break_processing: cannot find open file with " );
 282                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 283                         dbgtext( "allowing break to succeed.\n" );
 284                 }
 285                 return NULL;
 286         }
 287
 288         /* Ensure we have an oplock on the file */
 289
 290         /*
 291          * There is a potential race condition in that an oplock could
 292          * have been broken due to another udp request, and yet there are
 293          * still oplock break messages being sent in the udp message
 294          * queue for this file. So return true if we don't have an oplock,
 295          * as we may have just freed it.
 296          */
 297
 298         if(fsp->oplock_type == NO_OPLOCK) {
 299                 if( DEBUGLVL( 3 ) ) {
 300                         dbgtext( "initial_break_processing: file %s ",
 301                                  fsp_str_dbg(fsp));
 302                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 303                                  file_id_string_tos(&id), fsp->fh->gen_id );
 304                         dbgtext( "Allowing break to succeed regardless.\n" );
 305                 }
 306                 return NULL;
 307         }
 308
 309         return fsp;
 310 }
 311
 312 static void oplock_timeout_handler(struct event_context *ctx,
 313                                    struct timed_event *te,
 314                                    struct timeval now,
 315                                    void *private_data)
 316 {
 317         files_struct *fsp = (files_struct *)private_data;
 318
 319         /* Remove the timed event handler. */
 320         TALLOC_FREE(fsp->oplock_timeout);
 321         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 322                   fsp_str_dbg(fsp)));
 323         global_client_failed_oplock_break = True;
 324         remove_oplock(fsp);
 325         reply_to_oplock_break_requests(fsp);
 326 }
 327
 328 /*******************************************************************
 329  Add a timeout handler waiting for the client reply.
 330 *******************************************************************/
 331
 332 static void add_oplock_timeout_handler(files_struct *fsp)
 333 {
 334         /*
 335          * If kernel oplocks already notifies smbds when an oplock break times
 336          * out, just return.
 337          */
 338         if (koplocks &&
 339             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 340                 return;
 341         }
 342
 343         if (fsp->oplock_timeout != NULL) {
 344                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 345                           "around\n"));
 346         }
 347
 348         fsp->oplock_timeout =
 349                 event_add_timed(smbd_event_context(), fsp,
 350                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 351                                 oplock_timeout_handler, fsp);
 352
 353         if (fsp->oplock_timeout == NULL) {
 354                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 355         }
 356 }
 357
 358 static void send_break_message_smb1(files_struct *fsp, int level)
 359 {
 360         char *break_msg = new_break_message_smb1(talloc_tos(),
 361                                         fsp,
 362                                         level);
 363         if (break_msg == NULL) {
 364                 exit_server("Could not talloc break_msg\n");
 365         }
 366
 367         show_msg(break_msg);
 368         if (!srv_send_smb(smbd_server_fd(),
 369                         break_msg, false, 0,
 370                         IS_CONN_ENCRYPTED(fsp->conn),
 371                         NULL)) {
 372                 exit_server_cleanly("send_break_message_smb1: "
 373                         "srv_send_smb failed.");
 374         }
 375
 376         TALLOC_FREE(break_msg);
 377 }
 378
 379 void break_level2_to_none_async(files_struct *fsp)
 380 {
 381         struct smbd_server_connection *sconn = smbd_server_conn;
 382
 383         if (fsp->oplock_type == NO_OPLOCK) {
 384                 /* We already got a "break to none" message and we've handled
 385                  * it.  just ignore. */
 386                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 387                           "broken to none, ignoring.\n"));
 388                 return;
 389         }
 390
 391         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 392                 /* Don't tell the client, just downgrade. */
 393                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 394                           "downgrading fake level 2 oplock.\n"));
 395                 remove_oplock(fsp);
 396                 return;
 397         }
 398
 399         /* Ensure we're really at level2 state. */
 400         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 401
 402         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 403                   "to none message for fid %d, file %s\n", fsp->fnum,
 404                   fsp_str_dbg(fsp)));
 405
 406         /* Now send a break to none message to our client. */
 407         if (sconn->allow_smb2) {
 408                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 409         } else {
 410                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 411         }
 412
 413         /* Async level2 request, don't send a reply, just remove the oplock. */
 414         remove_oplock(fsp);
 415 }
 416
 417 /*******************************************************************
 418  This handles the case of a write triggering a break to none
 419  message on a level2 oplock.
 420  When we get this message we may be in any of three states :
 421  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 422  the client for LEVEL2.
 423 *******************************************************************/
 424
 425 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 426                                                       void *private_data,
 427                                                       uint32_t msg_type,
 428                                                       struct server_id src,
 429                                                       DATA_BLOB *data)
 430 {
 431         struct share_mode_entry msg;
 432         files_struct *fsp;
 433
 434         if (data->data == NULL) {
 435                 DEBUG(0, ("Got NULL buffer\n"));
 436                 return;
 437         }
 438
 439         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 440                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 441                 return;
 442         }
 443
 444         /* De-linearize incoming message. */
 445         message_to_share_mode_entry(&msg, (char *)data->data);
 446
 447         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 448                    "%s/%lu\n", procid_str(talloc_tos(), &src),
 449                    file_id_string_tos(&msg.id), msg.share_file_id));
 450
 451         fsp = initial_break_processing(msg.id, msg.share_file_id);
 452
 453         if (fsp == NULL) {
 454                 /* We hit a race here. Break messages are sent, and before we
 455                  * get to process this message, we have closed the file.
 456                  * No need to reply as this is an async message. */
 457                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 458                 return;
 459         }
 460
 461         break_level2_to_none_async(fsp);
 462 }
 463
 464 /*******************************************************************
 465  This handles the generic oplock break message from another smbd.
 466 *******************************************************************/
 467
 468 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 469                                          void *private_data,
 470                                          uint32_t msg_type,
 471                                          struct server_id src,
 472                                          DATA_BLOB *data)
 473 {
 474         struct smbd_server_connection *sconn = smbd_server_conn;
 475         struct share_mode_entry msg;
 476         files_struct *fsp;
 477         bool break_to_level2 = False;
 478
 479         if (data->data == NULL) {
 480                 DEBUG(0, ("Got NULL buffer\n"));
 481                 return;
 482         }
 483
 484         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 485                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 486                 return;
 487         }
 488
 489         /* De-linearize incoming message. */
 490         message_to_share_mode_entry(&msg, (char *)data->data);
 491
 492         DEBUG(10, ("Got oplock break message from pid %s: %s/%lu\n",
 493                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 494                    msg.share_file_id));
 495
 496         fsp = initial_break_processing(msg.id, msg.share_file_id);
 497
 498         if (fsp == NULL) {
 499                 /* We hit a race here. Break messages are sent, and before we
 500                  * get to process this message, we have closed the file. Reply
 501                  * with 'ok, oplock broken' */
 502                 DEBUG(3, ("Did not find fsp\n"));
 503
 504                 /* We just send the same message back. */
 505                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 506                                    (uint8 *)data->data,
 507                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 508                 return;
 509         }
 510
 511         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 512                 /* Remember we have to inform the requesting PID when the
 513                  * client replies */
 514                 msg.pid = src;
 515                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 516                              &fsp->pending_break_messages,
 517                              &fsp->num_pending_break_messages);
 518                 return;
 519         }
 520
 521         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 522             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 523                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 524                           file_id_string_tos(&fsp->file_id),
 525                           fsp_str_dbg(fsp)));
 526                 /* We just send the same message back. */
 527                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 528                                    (uint8 *)data->data,
 529                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 530                 return;
 531         }
 532
 533         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 534             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 535             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 536             lp_level2_oplocks(SNUM(fsp->conn))) {
 537                 break_to_level2 = True;
 538         }
 539
 540         /* Need to wait before sending a break
 541            message if we sent ourselves this message. */
 542         if (procid_is_me(&src)) {
 543                 wait_before_sending_break();
 544         }
 545
 546         if (sconn->allow_smb2) {
 547                 send_break_message_smb2(fsp, break_to_level2 ?
 548                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 549         } else {
 550                 send_break_message_smb1(fsp, break_to_level2 ?
 551                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 552         }
 553
 554         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 555
 556         msg.pid = src;
 557         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 558                      &fsp->pending_break_messages,
 559                      &fsp->num_pending_break_messages);
 560
 561         add_oplock_timeout_handler(fsp);
 562 }
 563
 564 /*******************************************************************
 565  This handles the kernel oplock break message.
 566 *******************************************************************/
 567
 568 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 569                                         void *private_data,
 570                                         uint32_t msg_type,
 571                                         struct server_id src,
 572                                         DATA_BLOB *data)
 573 {
 574         struct smbd_server_connection *sconn = smbd_server_conn;
 575         struct file_id id;
 576         unsigned long file_id;
 577         files_struct *fsp;
 578
 579         if (data->data == NULL) {
 580                 DEBUG(0, ("Got NULL buffer\n"));
 581                 return;
 582         }
 583
 584         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 585                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 586                 return;
 587         }
 588
 589         /* Pull the data from the message. */
 590         pull_file_id_24((char *)data->data, &id);
 591         file_id = (unsigned long)IVAL(data->data, 24);
 592
 593         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 594                    procid_str(talloc_tos(), &src), file_id_string_tos(&id),
 595                    (unsigned int)file_id));
 596
 597         fsp = initial_break_processing(id, file_id);
 598
 599         if (fsp == NULL) {
 600                 DEBUG(3, ("Got a kernel oplock break message for a file "
 601                           "I don't know about\n"));
 602                 return;
 603         }
 604
 605         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 606                 /* This is ok, kernel oplocks come in completely async */
 607                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 608                           "break reply\n"));
 609                 return;
 610         }
 611
 612         if (sconn->allow_smb2) {
 613                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 614         } else {
 615                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 616         }
 617
 618         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 619
 620         add_oplock_timeout_handler(fsp);
 621 }
 622
 623 void reply_to_oplock_break_requests(files_struct *fsp)
 624 {
 625         int i;
 626
 627         /*
 628          * If kernel oplocks already notifies smbds when oplocks are
 629          * broken/removed, just return.
 630          */
 631         if (koplocks &&
 632             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 633                 return;
 634         }
 635
 636         for (i=0; i<fsp->num_pending_break_messages; i++) {
 637                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 638                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 639
 640                 share_mode_entry_to_message(msg, e);
 641
 642                 messaging_send_buf(smbd_messaging_context(), e->pid,
 643                                    MSG_SMB_BREAK_RESPONSE,
 644                                    (uint8 *)msg,
 645                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 646         }
 647
 648         SAFE_FREE(fsp->pending_break_messages);
 649         fsp->num_pending_break_messages = 0;
 650         if (fsp->oplock_timeout != NULL) {
 651                 /* Remove the timed event handler. */
 652                 TALLOC_FREE(fsp->oplock_timeout);
 653                 fsp->oplock_timeout = NULL;
 654         }
 655         return;
 656 }
 657
 658 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 659                                           void *private_data,
 660                                           uint32_t msg_type,
 661                                           struct server_id src,
 662                                           DATA_BLOB *data)
 663 {
 664         struct share_mode_entry msg;
 665
 666         if (data->data == NULL) {
 667                 DEBUG(0, ("Got NULL buffer\n"));
 668                 return;
 669         }
 670
 671         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 672                 DEBUG(0, ("Got invalid msg len %u\n",
 673                           (unsigned int)data->length));
 674                 return;
 675         }
 676
 677         /* De-linearize incoming message. */
 678         message_to_share_mode_entry(&msg, (char *)data->data);
 679
 680         DEBUG(10, ("Got oplock break response from pid %s: %s/%lu mid %llu\n",
 681                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 682                    msg.share_file_id, (unsigned long long)msg.op_mid));
 683
 684         schedule_deferred_open_message_smb(msg.op_mid);
 685 }
 686
 687 static void process_open_retry_message(struct messaging_context *msg_ctx,
 688                                        void *private_data,
 689                                        uint32_t msg_type,
 690                                        struct server_id src,
 691                                        DATA_BLOB *data)
 692 {
 693         struct share_mode_entry msg;
 694
 695         if (data->data == NULL) {
 696                 DEBUG(0, ("Got NULL buffer\n"));
 697                 return;
 698         }
 699
 700         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 701                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 702                 return;
 703         }
 704
 705         /* De-linearize incoming message. */
 706         message_to_share_mode_entry(&msg, (char *)data->data);
 707
 708         DEBUG(10, ("Got open retry msg from pid %s: %s mid %llu\n",
 709                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 710                    (unsigned long long)msg.op_mid));
 711
 712         schedule_deferred_open_message_smb(msg.op_mid);
 713 }
 714
 715 /****************************************************************************
 716  This function is called on any file modification or lock request. If a file
 717  is level 2 oplocked then it must tell all other level 2 holders to break to
 718  none.
 719 ****************************************************************************/
 720
 721 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 722                                               enum level2_contention_type type)
 723 {
 724         int i;
 725         struct share_mode_lock *lck;
 726
 727         /*
 728          * If this file is level II oplocked then we need
 729          * to grab the shared memory lock and inform all
 730          * other files with a level II lock that they need
 731          * to flush their read caches. We keep the lock over
 732          * the shared memory area whilst doing this.
 733          */
 734
 735         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 736                 return;
 737
 738         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 739                                   NULL);
 740         if (lck == NULL) {
 741                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 742                          "share mode entry for file %s.\n", fsp_str_dbg(fsp)));
 743                 return;
 744         }
 745
 746         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 747                   lck->num_share_modes ));
 748
 749         for(i = 0; i < lck->num_share_modes; i++) {
 750                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 751                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 752
 753                 if (!is_valid_share_mode_entry(share_entry)) {
 754                         continue;
 755                 }
 756
 757                 /*
 758                  * As there could have been multiple writes waiting at the
 759                  * lock_share_entry gate we may not be the first to
 760                  * enter. Hence the state of the op_types in the share mode
 761                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 762                  * oplock. It will do no harm to re-send break messages to
 763                  * those smbd's that are still waiting their turn to remove
 764                  * their LEVEL_II state, and also no harm to ignore existing
 765                  * NO_OPLOCK states. JRA.
 766                  */
 767
 768                 DEBUG(10,("release_level_2_oplocks_on_change: "
 769                           "share_entry[%i]->op_type == %d\n",
 770                           i, share_entry->op_type ));
 771
 772                 if (share_entry->op_type == NO_OPLOCK) {
 773                         continue;
 774                 }
 775
 776                 /* Paranoia .... */
 777                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 778                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 779                                  "share mode entry %d is an exlusive "
 780                                  "oplock !\n", i ));
 781                         TALLOC_FREE(lck);
 782                         abort();
 783                 }
 784
 785                 share_mode_entry_to_message(msg, share_entry);
 786
 787                 /*
 788                  * Deal with a race condition when breaking level2
 789                  * oplocks. Don't send all the messages and release
 790                  * the lock, this allows someone else to come in and
 791                  * get a level2 lock before any of the messages are
 792                  * processed, and thus miss getting a break message.
 793                  * Ensure at least one entry (the one we're breaking)
 794                  * is processed immediately under the lock and becomes
 795                  * set as NO_OPLOCK to stop any waiter getting a level2.
 796                  * Bugid #5980.
 797                  */
 798
 799                 if (procid_is_me(&share_entry->pid)) {
 800                         wait_before_sending_break();
 801                         break_level2_to_none_async(fsp);
 802                 } else {
 803                         messaging_send_buf(smbd_messaging_context(),
 804                                         share_entry->pid,
 805                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 806                                         (uint8 *)msg,
 807                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 808                 }
 809         }
 810
 811         /* We let the message receivers handle removing the oplock state
 812            in the share mode lock db. */
 813
 814         TALLOC_FREE(lck);
 815 }
 816
 817 void contend_level2_oplocks_begin(files_struct *fsp,
 818                                   enum level2_contention_type type)
 819 {
 820         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 821                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 822                 return;
 823         }
 824
 825         contend_level2_oplocks_begin_default(fsp, type);
 826 }
 827
 828 void contend_level2_oplocks_end(files_struct *fsp,
 829                                 enum level2_contention_type type)
 830 {
 831         /* Only kernel oplocks implement this so far */
 832         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 833                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 834         }
 835 }
 836
 837 /****************************************************************************
 838  Linearize a share mode entry struct to an internal oplock break message.
 839 ****************************************************************************/
 840
 841 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 842 {
 843         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 844         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 845         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 846         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 847         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 848         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 849         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 850         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 851         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 852         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 853         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 854         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 855 #ifdef CLUSTER_SUPPORT
 856         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 857 #endif
 858 }
 859
 860 /****************************************************************************
 861  De-linearize an internal oplock break message to a share mode entry struct.
 862 ****************************************************************************/
 863
 864 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 865 {
 866         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 867         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 868         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 869         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 870         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 871         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 872         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 873         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 874         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 875         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 876         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 877         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 878 #ifdef CLUSTER_SUPPORT
 879         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 880 #endif
 881 }
 882
 883 /****************************************************************************
 884  Setup oplocks for this process.
 885 ****************************************************************************/
 886
 887 bool init_oplocks(struct messaging_context *msg_ctx)
 888 {
 889         DEBUG(3,("init_oplocks: initializing messages.\n"));
 890
 891         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 892                            process_oplock_break_message);
 893         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 894                            process_oplock_async_level2_break_message);
 895         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 896                            process_oplock_break_response);
 897         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 898                            process_kernel_oplock_break);
 899         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 900                            process_open_retry_message);
 901
 902         if (lp_kernel_oplocks()) {
 903 #if HAVE_KERNEL_OPLOCKS_IRIX
 904                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 905 #elif HAVE_KERNEL_OPLOCKS_LINUX
 906                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 907 #elif HAVE_ONEFS
 908                 koplocks = onefs_init_kernel_oplocks(talloc_autofree_context());
 909 #endif
 910         }
 911
 912         return True;
 913 }