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  * helper function used by the kernel oplock backends to post the break message
  31  */
  32 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  33 {
  34         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  35
  36         /* Put the kernel break info into the message. */
  37         push_file_id_24((char *)msg, &fsp->file_id);
  38         SIVAL(msg,24,fsp->fh->gen_id);
  39
  40         /* Don't need to be root here as we're only ever
  41            sending to ourselves. */
  42
  43         messaging_send_buf(msg_ctx, messaging_server_id(msg_ctx),
  44                            MSG_SMB_KERNEL_BREAK,
  45                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  46 }
  47
  48 /****************************************************************************
  49  Attempt to set an oplock on a file. Succeeds if kernel oplocks are
  50  disabled (just sets flags).
  51 ****************************************************************************/
  52
  53 NTSTATUS set_file_oplock(files_struct *fsp)
  54 {
  55         struct smbd_server_connection *sconn = fsp->conn->sconn;
  56         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
  57         bool use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
  58
  59         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  60                 if (use_kernel &&
  61                     !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
  62                         DEBUG(10, ("Refusing level2 oplock, kernel oplocks "
  63                                    "don't support them\n"));
  64                         return NT_STATUS_NOT_SUPPORTED;
  65                 }
  66         }
  67
  68         if ((fsp->oplock_type != NO_OPLOCK) &&
  69             use_kernel &&
  70             !koplocks->ops->set_oplock(koplocks, fsp, fsp->oplock_type))
  71         {
  72                 return map_nt_error_from_unix(errno);
  73         }
  74
  75         fsp->sent_oplock_break = NO_BREAK_SENT;
  76         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  77                 sconn->oplocks.level_II_open++;
  78         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  79                 sconn->oplocks.exclusive_open++;
  80         }
  81
  82         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  83                     "tv_sec = %x, tv_usec = %x\n",
  84                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  85                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  86                  (int)fsp->open_time.tv_usec ));
  87
  88         return NT_STATUS_OK;
  89 }
  90
  91 /****************************************************************************
  92  Attempt to release an oplock on a file. Decrements oplock count.
  93 ****************************************************************************/
  94
  95 static void release_file_oplock(files_struct *fsp)
  96 {
  97         struct smbd_server_connection *sconn = fsp->conn->sconn;
  98         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
  99
 100         if ((fsp->oplock_type != NO_OPLOCK) &&
 101             koplocks) {
 102                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 103         }
 104
 105         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 106                 sconn->oplocks.level_II_open--;
 107         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 108                 sconn->oplocks.exclusive_open--;
 109         }
 110
 111         SMB_ASSERT(sconn->oplocks.exclusive_open>=0);
 112         SMB_ASSERT(sconn->oplocks.level_II_open>=0);
 113
 114         fsp->oplock_type = NO_OPLOCK;
 115         fsp->sent_oplock_break = NO_BREAK_SENT;
 116
 117         flush_write_cache(fsp, SAMBA_OPLOCK_RELEASE_FLUSH);
 118         delete_write_cache(fsp);
 119
 120         TALLOC_FREE(fsp->oplock_timeout);
 121 }
 122
 123 /****************************************************************************
 124  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 125 ****************************************************************************/
 126
 127 static void downgrade_file_oplock(files_struct *fsp)
 128 {
 129         struct smbd_server_connection *sconn = fsp->conn->sconn;
 130         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 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         sconn->oplocks.exclusive_open--;
 142         sconn->oplocks.level_II_open++;
 143         fsp->sent_oplock_break = NO_BREAK_SENT;
 144
 145         flush_write_cache(fsp, SAMBA_OPLOCK_RELEASE_FLUSH);
 146         delete_write_cache(fsp);
 147
 148         TALLOC_FREE(fsp->oplock_timeout);
 149 }
 150
 151 /****************************************************************************
 152  Remove a file oplock. Copes with level II and exclusive.
 153  Locks then unlocks the share mode lock. Client can decide to go directly
 154  to none even if a "break-to-level II" was sent.
 155 ****************************************************************************/
 156
 157 bool remove_oplock(files_struct *fsp)
 158 {
 159         bool ret;
 160         struct share_mode_lock *lck;
 161
 162         DEBUG(10, ("remove_oplock called for %s\n",
 163                    fsp_str_dbg(fsp)));
 164
 165         /* Remove the oplock flag from the sharemode. */
 166         lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 167         if (lck == NULL) {
 168                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 169                          "file %s\n", fsp_str_dbg(fsp)));
 170                 return False;
 171         }
 172
 173         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 174
 175                 /*
 176                  * If we're the only LEVEL_II holder, we have to remove the
 177                  * have_read_oplocks from the brlock entry
 178                  */
 179
 180                 struct share_mode_data *data = lck->data;
 181                 uint32_t i, num_level2;
 182
 183                 num_level2 = 0;
 184                 for (i=0; i<data->num_share_modes; i++) {
 185                         if (data->share_modes[i].op_type == LEVEL_II_OPLOCK) {
 186                                 num_level2 += 1;
 187                         }
 188                         if (num_level2 > 1) {
 189                                 /*
 190                                  * No need to count them all...
 191                                  */
 192                                 break;
 193                         }
 194                 }
 195
 196                 if (num_level2 == 1) {
 197                         /*
 198                          * That's only us. We are dropping that level2 oplock,
 199                          * so remove the brlock flag.
 200                          */
 201                         struct byte_range_lock *brl;
 202
 203                         brl = brl_get_locks(talloc_tos(), fsp);
 204                         if (brl) {
 205                                 brl_set_have_read_oplocks(brl, false);
 206                                 TALLOC_FREE(brl);
 207                         }
 208                 }
 209         }
 210
 211         ret = remove_share_oplock(lck, fsp);
 212         if (!ret) {
 213                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 214                          "file %s, %s, %s\n",
 215                          fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 216                          file_id_string_tos(&fsp->file_id)));
 217         }
 218         release_file_oplock(fsp);
 219         TALLOC_FREE(lck);
 220         return ret;
 221 }
 222
 223 /*
 224  * Deal with a reply when a break-to-level II was sent.
 225  */
 226 bool downgrade_oplock(files_struct *fsp)
 227 {
 228         bool ret;
 229         struct share_mode_lock *lck;
 230         struct byte_range_lock *brl;
 231
 232         DEBUG(10, ("downgrade_oplock called for %s\n",
 233                    fsp_str_dbg(fsp)));
 234
 235         lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 236         if (lck == NULL) {
 237                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 238                          "file %s\n", fsp_str_dbg(fsp)));
 239                 return False;
 240         }
 241         ret = downgrade_share_oplock(lck, fsp);
 242         if (!ret) {
 243                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 244                          "for file %s, %s, file_id %s\n",
 245                          fsp_str_dbg(fsp), fsp_fnum_dbg(fsp),
 246                          file_id_string_tos(&fsp->file_id)));
 247         }
 248
 249         downgrade_file_oplock(fsp);
 250
 251         brl = brl_get_locks(talloc_tos(), fsp);
 252         if (brl != NULL) {
 253                 brl_set_have_read_oplocks(brl, true);
 254                 TALLOC_FREE(brl);
 255         }
 256
 257         TALLOC_FREE(lck);
 258         return ret;
 259 }
 260
 261 /****************************************************************************
 262  Set up an oplock break message.
 263 ****************************************************************************/
 264
 265 #define SMB1_BREAK_MESSAGE_LENGTH (smb_size + 8*2)
 266
 267 static void new_break_message_smb1(files_struct *fsp, int cmd,
 268                                    char result[SMB1_BREAK_MESSAGE_LENGTH])
 269 {
 270         memset(result,'\0',smb_size);
 271         srv_set_message(result,8,0,true);
 272         SCVAL(result,smb_com,SMBlockingX);
 273         SSVAL(result,smb_tid,fsp->conn->cnum);
 274         SSVAL(result,smb_pid,0xFFFF);
 275         SSVAL(result,smb_uid,0);
 276         SSVAL(result,smb_mid,0xFFFF);
 277         SCVAL(result,smb_vwv0,0xFF);
 278         SSVAL(result,smb_vwv2,fsp->fnum);
 279         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 280         SCVAL(result,smb_vwv3+1,cmd);
 281 }
 282
 283 /****************************************************************************
 284  Function to do the waiting before sending a local break.
 285 ****************************************************************************/
 286
 287 static void wait_before_sending_break(void)
 288 {
 289         long wait_time = (long)lp_oplock_break_wait_time();
 290
 291         if (wait_time) {
 292                 smb_msleep(wait_time);
 293         }
 294 }
 295
 296 /****************************************************************************
 297  Ensure that we have a valid oplock.
 298 ****************************************************************************/
 299
 300 static files_struct *initial_break_processing(
 301         struct smbd_server_connection *sconn, struct file_id id,
 302         unsigned long file_id)
 303 {
 304         files_struct *fsp = NULL;
 305
 306         DEBUG(3, ("initial_break_processing: called for %s/%u\n"
 307                   "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 308                   file_id_string_tos(&id), (int)file_id,
 309                   sconn->oplocks.exclusive_open,
 310                   sconn->oplocks.level_II_open));
 311
 312         /*
 313          * We need to search the file open table for the
 314          * entry containing this dev and inode, and ensure
 315          * we have an oplock on it.
 316          */
 317
 318         fsp = file_find_dif(sconn, id, file_id);
 319
 320         if(fsp == NULL) {
 321                 /* The file could have been closed in the meantime - return success. */
 322                 DEBUG(3, ("initial_break_processing: cannot find open file "
 323                           "with file_id %s gen_id = %lu, allowing break to "
 324                           "succeed.\n", file_id_string_tos(&id), file_id));
 325                 return NULL;
 326         }
 327
 328         /* Ensure we have an oplock on the file */
 329
 330         /*
 331          * There is a potential race condition in that an oplock could
 332          * have been broken due to another udp request, and yet there are
 333          * still oplock break messages being sent in the udp message
 334          * queue for this file. So return true if we don't have an oplock,
 335          * as we may have just freed it.
 336          */
 337
 338         if(fsp->oplock_type == NO_OPLOCK) {
 339                 DEBUG(3, ("initial_break_processing: file %s (file_id = %s "
 340                           "gen_id = %lu) has no oplock. Allowing break to "
 341                           "succeed regardless.\n", fsp_str_dbg(fsp),
 342                           file_id_string_tos(&id), fsp->fh->gen_id));
 343                 return NULL;
 344         }
 345
 346         return fsp;
 347 }
 348
 349 static void oplock_timeout_handler(struct tevent_context *ctx,
 350                                    struct tevent_timer *te,
 351                                    struct timeval now,
 352                                    void *private_data)
 353 {
 354         files_struct *fsp = (files_struct *)private_data;
 355
 356         SMB_ASSERT(fsp->sent_oplock_break != NO_BREAK_SENT);
 357
 358         /* Remove the timed event handler. */
 359         TALLOC_FREE(fsp->oplock_timeout);
 360         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 361                   fsp_str_dbg(fsp)));
 362         remove_oplock(fsp);
 363 }
 364
 365 /*******************************************************************
 366  Add a timeout handler waiting for the client reply.
 367 *******************************************************************/
 368
 369 static void add_oplock_timeout_handler(files_struct *fsp)
 370 {
 371         struct smbd_server_connection *sconn = fsp->conn->sconn;
 372         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 373
 374         /*
 375          * If kernel oplocks already notifies smbds when an oplock break times
 376          * out, just return.
 377          */
 378         if (koplocks &&
 379             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 380                 return;
 381         }
 382
 383         if (fsp->oplock_timeout != NULL) {
 384                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 385                           "around\n"));
 386         }
 387
 388         fsp->oplock_timeout =
 389                 tevent_add_timer(fsp->conn->sconn->ev_ctx, fsp,
 390                                  timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 391                                  oplock_timeout_handler, fsp);
 392
 393         if (fsp->oplock_timeout == NULL) {
 394                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 395         }
 396 }
 397
 398 static void send_break_message_smb1(files_struct *fsp, int level)
 399 {
 400         struct smbXsrv_connection *xconn = NULL;
 401         char break_msg[SMB1_BREAK_MESSAGE_LENGTH];
 402
 403         /*
 404          * For SMB1 we only have one connection
 405          */
 406         xconn = fsp->conn->sconn->client->connections;
 407
 408         new_break_message_smb1(fsp, level, break_msg);
 409
 410         show_msg(break_msg);
 411         if (!srv_send_smb(xconn,
 412                         break_msg, false, 0,
 413                         IS_CONN_ENCRYPTED(fsp->conn),
 414                         NULL)) {
 415                 exit_server_cleanly("send_break_message_smb1: "
 416                         "srv_send_smb failed.");
 417         }
 418 }
 419
 420 /*******************************************************************
 421  This handles the generic oplock break message from another smbd.
 422 *******************************************************************/
 423
 424 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 425                                          void *private_data,
 426                                          uint32_t msg_type,
 427                                          struct server_id src,
 428                                          DATA_BLOB *data)
 429 {
 430         struct share_mode_entry msg;
 431         files_struct *fsp;
 432         bool break_to_level2 = False;
 433         bool use_kernel;
 434         struct smbd_server_connection *sconn =
 435                 talloc_get_type_abort(private_data,
 436                 struct smbd_server_connection);
 437         struct server_id self = messaging_server_id(sconn->msg_ctx);
 438         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 439         uint16_t break_to;
 440
 441         if (data->data == NULL) {
 442                 DEBUG(0, ("Got NULL buffer\n"));
 443                 return;
 444         }
 445
 446         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 447                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 448                 return;
 449         }
 450
 451         /* De-linearize incoming message. */
 452         message_to_share_mode_entry(&msg, (char *)data->data);
 453         break_to = msg.op_type;
 454
 455         DEBUG(10, ("Got oplock break to %u message from pid %s: %s/%llu\n",
 456                    (unsigned)break_to, server_id_str(talloc_tos(), &src),
 457                    file_id_string_tos(&msg.id),
 458                    (unsigned long long)msg.share_file_id));
 459
 460         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 461
 462         if (fsp == NULL) {
 463                 /* We hit a race here. Break messages are sent, and before we
 464                  * get to process this message, we have closed the file. */
 465                 DEBUG(3, ("Did not find fsp\n"));
 466                 return;
 467         }
 468
 469         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 470                 /*
 471                  * Nothing to do anymore
 472                  */
 473                 return;
 474         }
 475
 476         if (break_to == fsp->oplock_type) {
 477                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 478                           file_id_string_tos(&fsp->file_id),
 479                           fsp_str_dbg(fsp)));
 480                 return;
 481         }
 482
 483         use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
 484
 485         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 486             (break_to != NO_OPLOCK) &&
 487             !(use_kernel && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 488             lp_level2_oplocks(SNUM(fsp->conn))) {
 489                 break_to_level2 = True;
 490         }
 491
 492         /* Need to wait before sending a break
 493            message if we sent ourselves this message. */
 494         if (serverid_equal(&self, &src)) {
 495                 wait_before_sending_break();
 496         }
 497
 498         if (sconn->using_smb2) {
 499                 send_break_message_smb2(fsp, break_to_level2 ?
 500                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 501         } else {
 502                 send_break_message_smb1(fsp, break_to_level2 ?
 503                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 504         }
 505
 506         if ((fsp->oplock_type == LEVEL_II_OPLOCK) && (break_to == NO_OPLOCK)) {
 507                 /*
 508                  * This is an async break without a reply and thus no timeout
 509                  */
 510                 remove_oplock(fsp);
 511                 return;
 512         }
 513         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 514         add_oplock_timeout_handler(fsp);
 515 }
 516
 517 /*******************************************************************
 518  This handles the kernel oplock break message.
 519 *******************************************************************/
 520
 521 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 522                                         void *private_data,
 523                                         uint32_t msg_type,
 524                                         struct server_id src,
 525                                         DATA_BLOB *data)
 526 {
 527         struct file_id id;
 528         unsigned long file_id;
 529         files_struct *fsp;
 530         struct smbd_server_connection *sconn =
 531                 talloc_get_type_abort(private_data,
 532                 struct smbd_server_connection);
 533
 534         if (data->data == NULL) {
 535                 DEBUG(0, ("Got NULL buffer\n"));
 536                 return;
 537         }
 538
 539         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 540                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 541                 return;
 542         }
 543
 544         /* Pull the data from the message. */
 545         pull_file_id_24((char *)data->data, &id);
 546         file_id = (unsigned long)IVAL(data->data, 24);
 547
 548         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 549                    server_id_str(talloc_tos(), &src), file_id_string_tos(&id),
 550                    (unsigned int)file_id));
 551
 552         fsp = initial_break_processing(sconn, id, file_id);
 553
 554         if (fsp == NULL) {
 555                 DEBUG(3, ("Got a kernel oplock break message for a file "
 556                           "I don't know about\n"));
 557                 return;
 558         }
 559
 560         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 561                 /* This is ok, kernel oplocks come in completely async */
 562                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 563                           "break reply\n"));
 564                 return;
 565         }
 566
 567         if (sconn->using_smb2) {
 568                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 569         } else {
 570                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 571         }
 572
 573         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 574
 575         add_oplock_timeout_handler(fsp);
 576 }
 577
 578 struct break_to_none_state {
 579         struct smbd_server_connection *sconn;
 580         struct file_id id;
 581 };
 582 static void do_break_to_none(struct tevent_context *ctx,
 583                              struct tevent_immediate *im,
 584                              void *private_data);
 585
 586 /****************************************************************************
 587  This function is called on any file modification or lock request. If a file
 588  is level 2 oplocked then it must tell all other level 2 holders to break to
 589  none.
 590 ****************************************************************************/
 591
 592 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 593                                               enum level2_contention_type type)
 594 {
 595         struct smbd_server_connection *sconn = fsp->conn->sconn;
 596         struct tevent_immediate *im;
 597         struct break_to_none_state *state;
 598         struct byte_range_lock *brl;
 599
 600         /*
 601          * If this file is level II oplocked then we need
 602          * to grab the shared memory lock and inform all
 603          * other files with a level II lock that they need
 604          * to flush their read caches. We keep the lock over
 605          * the shared memory area whilst doing this.
 606          */
 607
 608         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 609                 /*
 610                  * There can't be any level2 oplocks, we're alone.
 611                  */
 612                 return;
 613         }
 614
 615         brl = brl_get_locks_readonly(fsp);
 616         if ((brl != NULL) && !brl_have_read_oplocks(brl)) {
 617                 DEBUG(10, ("No read oplocks around\n"));
 618                 return;
 619         }
 620
 621         /*
 622          * When we get here we might have a brlock entry locked. Also
 623          * locking the share mode entry would violate the locking
 624          * order. Breaking level2 oplocks to none is asynchronous
 625          * anyway, so we postpone this into an immediate event.
 626          */
 627
 628         state = talloc(sconn, struct break_to_none_state);
 629         if (state == NULL) {
 630                 DEBUG(1, ("talloc failed\n"));
 631                 return;
 632         }
 633         state->sconn = sconn;
 634         state->id = fsp->file_id;
 635
 636         im = tevent_create_immediate(state);
 637         if (im == NULL) {
 638                 DEBUG(1, ("tevent_create_immediate failed\n"));
 639                 TALLOC_FREE(state);
 640                 return;
 641         }
 642         tevent_schedule_immediate(im, sconn->ev_ctx, do_break_to_none, state);
 643 }
 644
 645 static void do_break_to_none(struct tevent_context *ctx,
 646                              struct tevent_immediate *im,
 647                              void *private_data)
 648 {
 649         struct break_to_none_state *state = talloc_get_type_abort(
 650                 private_data, struct break_to_none_state);
 651         int i;
 652         struct share_mode_lock *lck;
 653
 654         lck = get_existing_share_mode_lock(talloc_tos(), state->id);
 655         if (lck == NULL) {
 656                 DEBUG(1, ("%s: failed to lock share mode entry for file %s.\n",
 657                           __func__, file_id_string_tos(&state->id)));
 658                 goto done;
 659         }
 660
 661         DEBUG(10,("%s: num_share_modes = %d\n", __func__,
 662                   lck->data->num_share_modes ));
 663
 664         for(i = 0; i < lck->data->num_share_modes; i++) {
 665                 struct share_mode_entry *share_entry = &lck->data->share_modes[i];
 666                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 667
 668                 if (!is_valid_share_mode_entry(share_entry)) {
 669                         continue;
 670                 }
 671
 672                 /*
 673                  * As there could have been multiple writes waiting at the
 674                  * lock_share_entry gate we may not be the first to
 675                  * enter. Hence the state of the op_types in the share mode
 676                  * entries may be partly NO_OPLOCK and partly LEVEL_II
 677                  * oplock. It will do no harm to re-send break messages to
 678                  * those smbd's that are still waiting their turn to remove
 679                  * their LEVEL_II state, and also no harm to ignore existing
 680                  * NO_OPLOCK states. JRA.
 681                  */
 682
 683                 DEBUG(10,("%s: share_entry[%i]->op_type == %d\n", __func__,
 684                           i, share_entry->op_type ));
 685
 686                 if (share_entry->op_type == NO_OPLOCK) {
 687                         continue;
 688                 }
 689
 690                 /* Paranoia .... */
 691                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 692                         DEBUG(0,("%s: PANIC. "
 693                                  "share mode entry %d is an exlusive "
 694                                  "oplock !\n", __func__, i ));
 695                         TALLOC_FREE(lck);
 696                         abort();
 697                 }
 698
 699                 share_mode_entry_to_message(msg, share_entry);
 700                 /* Overload entry->op_type */
 701                 SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET, NO_OPLOCK);
 702
 703                 messaging_send_buf(state->sconn->msg_ctx, share_entry->pid,
 704                                    MSG_SMB_BREAK_REQUEST,
 705                                    (uint8 *)msg, sizeof(msg));
 706         }
 707
 708         /* We let the message receivers handle removing the oplock state
 709            in the share mode lock db. */
 710
 711         TALLOC_FREE(lck);
 712 done:
 713         TALLOC_FREE(state);
 714         return;
 715 }
 716
 717 void smbd_contend_level2_oplocks_begin(files_struct *fsp,
 718                                   enum level2_contention_type type)
 719 {
 720         struct smbd_server_connection *sconn = fsp->conn->sconn;
 721         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 722
 723         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 724                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 725                 return;
 726         }
 727
 728         contend_level2_oplocks_begin_default(fsp, type);
 729 }
 730
 731 void smbd_contend_level2_oplocks_end(files_struct *fsp,
 732                                 enum level2_contention_type type)
 733 {
 734         struct smbd_server_connection *sconn = fsp->conn->sconn;
 735         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 736
 737         /* Only kernel oplocks implement this so far */
 738         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 739                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 740         }
 741 }
 742
 743 /****************************************************************************
 744  Linearize a share mode entry struct to an internal oplock break message.
 745 ****************************************************************************/
 746
 747 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 748 {
 749         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 750         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 751         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 752         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 753         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 754         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 755         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 756         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 757         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 758         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 759         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 760         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 761         SIVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET,e->name_hash);
 762         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 763 }
 764
 765 /****************************************************************************
 766  De-linearize an internal oplock break message to a share mode entry struct.
 767 ****************************************************************************/
 768
 769 void message_to_share_mode_entry(struct share_mode_entry *e, const char *msg)
 770 {
 771         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 772         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 773         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 774         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 775         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 776         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 777         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 778         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 779         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 780         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 781         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 782         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 783         e->name_hash = IVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET);
 784         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 785 }
 786
 787 /****************************************************************************
 788  Setup oplocks for this process.
 789 ****************************************************************************/
 790
 791 bool init_oplocks(struct smbd_server_connection *sconn)
 792 {
 793         DEBUG(3,("init_oplocks: initializing messages.\n"));
 794
 795         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_REQUEST,
 796                            process_oplock_break_message);
 797         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_KERNEL_BREAK,
 798                            process_kernel_oplock_break);
 799         return true;
 800 }
 801
 802 void init_kernel_oplocks(struct smbd_server_connection *sconn)
 803 {
 804         struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 805
 806         /* only initialize once */
 807         if (koplocks == NULL) {
 808 #if HAVE_KERNEL_OPLOCKS_IRIX
 809                 koplocks = irix_init_kernel_oplocks(sconn);
 810 #elif HAVE_KERNEL_OPLOCKS_LINUX
 811                 koplocks = linux_init_kernel_oplocks(sconn);
 812 #endif
 813                 sconn->oplocks.kernel_ops = koplocks;
 814         }
 815 }