source3/smbd/oplock.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    oplock processing
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 1998 - 2001
   6    Copyright (C) Volker Lendecke 2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #define DBGC_CLASS DBGC_LOCKING
  23 #include "includes.h"
  24 #include "smbd/globals.h"
  25
  26 /****************************************************************************
  27  Get the number of current exclusive oplocks.
  28 ****************************************************************************/
  29
  30 int32 get_number_of_exclusive_open_oplocks(void)
  31 {
  32   return exclusive_oplocks_open;
  33 }
  34
  35 /****************************************************************************
  36  Return True if an oplock message is pending.
  37 ****************************************************************************/
  38
  39 bool oplock_message_waiting(void)
  40 {
  41         if (koplocks && koplocks->ops->msg_waiting(koplocks)) {
  42                 return True;
  43         }
  44
  45         return False;
  46 }
  47
  48 /****************************************************************************
  49  Find out if there are any kernel oplock messages waiting and process them
  50  if so. pfds is the fd_set from the main select loop (which contains any
  51  kernel oplock fd if that's what the system uses (IRIX). If may be NULL if
  52  we're calling this in a shutting down state.
  53 ****************************************************************************/
  54
  55 void process_kernel_oplocks(struct messaging_context *msg_ctx)
  56 {
  57         /*
  58          * We need to check for kernel oplocks before going into the select
  59          * here, as the EINTR generated by the linux kernel oplock may have
  60          * already been eaten. JRA.
  61          */
  62
  63         if (!koplocks) {
  64                 return;
  65         }
  66
  67         while (koplocks->ops->msg_waiting(koplocks)) {
  68                 files_struct *fsp;
  69                 char msg[MSG_SMB_KERNEL_BREAK_SIZE];
  70
  71                 fsp = koplocks->ops->receive_message(koplocks);
  72
  73                 if (fsp == NULL) {
  74                         DEBUG(3, ("Kernel oplock message announced, but none "
  75                                   "received\n"));
  76                         return;
  77                 }
  78
  79                 /* Put the kernel break info into the message. */
  80                 push_file_id_16(msg, &fsp->file_id);
  81                 SIVAL(msg,16,fsp->fh->gen_id);
  82
  83                 /* Don't need to be root here as we're only ever
  84                    sending to ourselves. */
  85
  86                 messaging_send_buf(msg_ctx, procid_self(),
  87                                    MSG_SMB_KERNEL_BREAK,
  88                                    (uint8 *)&msg, MSG_SMB_KERNEL_BREAK_SIZE);
  89         }
  90 }
  91
  92 /****************************************************************************
  93  Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
  94  disabled (just sets flags). Returns True if oplock set.
  95 ****************************************************************************/
  96
  97 bool set_file_oplock(files_struct *fsp, int oplock_type)
  98 {
  99         if ((fsp->oplock_type != NO_OPLOCK) &&
 100             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 101             koplocks &&
 102             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
 103                 return False;
 104         }
 105
 106         fsp->oplock_type = oplock_type;
 107         fsp->sent_oplock_break = NO_BREAK_SENT;
 108         if (oplock_type == LEVEL_II_OPLOCK) {
 109                 level_II_oplocks_open++;
 110         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 111                 exclusive_oplocks_open++;
 112         }
 113
 114         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
 115                     "tv_sec = %x, tv_usec = %x\n",
 116                  fsp->fsp_name, file_id_string_tos(&fsp->file_id),
 117                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
 118                  (int)fsp->open_time.tv_usec ));
 119
 120         return True;
 121 }
 122
 123 /****************************************************************************
 124  Attempt to release an oplock on a file. Decrements oplock count.
 125 ****************************************************************************/
 126
 127 void release_file_oplock(files_struct *fsp)
 128 {
 129         if ((fsp->oplock_type != NO_OPLOCK) &&
 130             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 131             koplocks) {
 132                 koplocks->ops->release_oplock(koplocks, fsp);
 133         }
 134
 135         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 136                 level_II_oplocks_open--;
 137         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 138                 exclusive_oplocks_open--;
 139         }
 140
 141         SMB_ASSERT(exclusive_oplocks_open>=0);
 142         SMB_ASSERT(level_II_oplocks_open>=0);
 143
 144         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 145                 /* This doesn't matter for close. */
 146                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 147         } else {
 148                 fsp->oplock_type = NO_OPLOCK;
 149         }
 150         fsp->sent_oplock_break = NO_BREAK_SENT;
 151
 152         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 153
 154         TALLOC_FREE(fsp->oplock_timeout);
 155 }
 156
 157 /****************************************************************************
 158  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 159 ****************************************************************************/
 160
 161 static void downgrade_file_oplock(files_struct *fsp)
 162 {
 163         if (koplocks) {
 164                 koplocks->ops->release_oplock(koplocks, fsp);
 165         }
 166         fsp->oplock_type = LEVEL_II_OPLOCK;
 167         exclusive_oplocks_open--;
 168         level_II_oplocks_open++;
 169         fsp->sent_oplock_break = NO_BREAK_SENT;
 170 }
 171
 172 /****************************************************************************
 173  Remove a file oplock. Copes with level II and exclusive.
 174  Locks then unlocks the share mode lock. Client can decide to go directly
 175  to none even if a "break-to-level II" was sent.
 176 ****************************************************************************/
 177
 178 bool remove_oplock(files_struct *fsp)
 179 {
 180         bool ret;
 181         struct share_mode_lock *lck;
 182
 183         /* Remove the oplock flag from the sharemode. */
 184         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 185                                   NULL);
 186         if (lck == NULL) {
 187                 DEBUG(0,("remove_oplock: failed to lock share entry for "
 188                          "file %s\n", fsp->fsp_name ));
 189                 return False;
 190         }
 191         ret = remove_share_oplock(lck, fsp);
 192         if (!ret) {
 193                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 194                          "file %s fnum %d, %s\n",
 195                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 196         }
 197         release_file_oplock(fsp);
 198         TALLOC_FREE(lck);
 199         return ret;
 200 }
 201
 202 /*
 203  * Deal with a reply when a break-to-level II was sent.
 204  */
 205 bool downgrade_oplock(files_struct *fsp)
 206 {
 207         bool ret;
 208         struct share_mode_lock *lck;
 209
 210         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 211                                   NULL);
 212         if (lck == NULL) {
 213                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 214                          "file %s\n", fsp->fsp_name ));
 215                 return False;
 216         }
 217         ret = downgrade_share_oplock(lck, fsp);
 218         if (!ret) {
 219                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 220                          "for file %s fnum %d, file_id %s\n",
 221                          fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
 222         }
 223
 224         downgrade_file_oplock(fsp);
 225         TALLOC_FREE(lck);
 226         return ret;
 227 }
 228
 229 /****************************************************************************
 230  Set up an oplock break message.
 231 ****************************************************************************/
 232
 233 static char *new_break_smb_message(TALLOC_CTX *mem_ctx,
 234                                    files_struct *fsp, uint8 cmd)
 235 {
 236         char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
 237
 238         if (result == NULL) {
 239                 DEBUG(0, ("talloc failed\n"));
 240                 return NULL;
 241         }
 242
 243         memset(result,'\0',smb_size);
 244         srv_set_message(result,8,0,true);
 245         SCVAL(result,smb_com,SMBlockingX);
 246         SSVAL(result,smb_tid,fsp->conn->cnum);
 247         SSVAL(result,smb_pid,0xFFFF);
 248         SSVAL(result,smb_uid,0);
 249         SSVAL(result,smb_mid,0xFFFF);
 250         SCVAL(result,smb_vwv0,0xFF);
 251         SSVAL(result,smb_vwv2,fsp->fnum);
 252         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 253         SCVAL(result,smb_vwv3+1,cmd);
 254         return result;
 255 }
 256
 257 /****************************************************************************
 258  Function to do the waiting before sending a local break.
 259 ****************************************************************************/
 260
 261 static void wait_before_sending_break(void)
 262 {
 263         long wait_time = (long)lp_oplock_break_wait_time();
 264
 265         if (wait_time) {
 266                 smb_msleep(wait_time);
 267         }
 268 }
 269
 270 /****************************************************************************
 271  Ensure that we have a valid oplock.
 272 ****************************************************************************/
 273
 274 static files_struct *initial_break_processing(struct file_id id, unsigned long file_id)
 275 {
 276         files_struct *fsp = NULL;
 277
 278         if( DEBUGLVL( 3 ) ) {
 279                 dbgtext( "initial_break_processing: called for %s/%u\n",
 280                          file_id_string_tos(&id), (int)file_id);
 281                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 282                         exclusive_oplocks_open, level_II_oplocks_open );
 283         }
 284
 285         /*
 286          * We need to search the file open table for the
 287          * entry containing this dev and inode, and ensure
 288          * we have an oplock on it.
 289          */
 290
 291         fsp = file_find_dif(id, file_id);
 292
 293         if(fsp == NULL) {
 294                 /* The file could have been closed in the meantime - return success. */
 295                 if( DEBUGLVL( 3 ) ) {
 296                         dbgtext( "initial_break_processing: cannot find open file with " );
 297                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 298                         dbgtext( "allowing break to succeed.\n" );
 299                 }
 300                 return NULL;
 301         }
 302
 303         /* Ensure we have an oplock on the file */
 304
 305         /*
 306          * There is a potential race condition in that an oplock could
 307          * have been broken due to another udp request, and yet there are
 308          * still oplock break messages being sent in the udp message
 309          * queue for this file. So return true if we don't have an oplock,
 310          * as we may have just freed it.
 311          */
 312
 313         if(fsp->oplock_type == NO_OPLOCK) {
 314                 if( DEBUGLVL( 3 ) ) {
 315                         dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
 316                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 317                                  file_id_string_tos(&id), fsp->fh->gen_id );
 318                         dbgtext( "Allowing break to succeed regardless.\n" );
 319                 }
 320                 return NULL;
 321         }
 322
 323         return fsp;
 324 }
 325
 326 static void oplock_timeout_handler(struct event_context *ctx,
 327                                    struct timed_event *te,
 328                                    struct timeval now,
 329                                    void *private_data)
 330 {
 331         files_struct *fsp = (files_struct *)private_data;
 332
 333         /* Remove the timed event handler. */
 334         TALLOC_FREE(fsp->oplock_timeout);
 335         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n", fsp->fsp_name));
 336         global_client_failed_oplock_break = True;
 337         remove_oplock(fsp);
 338         reply_to_oplock_break_requests(fsp);
 339 }
 340
 341 /*******************************************************************
 342  Add a timeout handler waiting for the client reply.
 343 *******************************************************************/
 344
 345 static void add_oplock_timeout_handler(files_struct *fsp)
 346 {
 347         if (fsp->oplock_timeout != NULL) {
 348                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 349                           "around\n"));
 350         }
 351
 352         fsp->oplock_timeout =
 353                 event_add_timed(smbd_event_context(), NULL,
 354                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 355                                 oplock_timeout_handler, fsp);
 356
 357         if (fsp->oplock_timeout == NULL) {
 358                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 359         }
 360 }
 361
 362 /*******************************************************************
 363  This handles the case of a write triggering a break to none
 364  message on a level2 oplock.
 365  When we get this message we may be in any of three states :
 366  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 367  the client for LEVEL2.
 368 *******************************************************************/
 369
 370 static void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 371                                                       void *private_data,
 372                                                       uint32_t msg_type,
 373                                                       struct server_id src,
 374                                                       DATA_BLOB *data)
 375 {
 376         struct share_mode_entry msg;
 377         files_struct *fsp;
 378         char *break_msg;
 379         bool sign_state;
 380
 381         if (data->data == NULL) {
 382                 DEBUG(0, ("Got NULL buffer\n"));
 383                 return;
 384         }
 385
 386         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 387                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 388                 return;
 389         }
 390
 391         /* De-linearize incoming message. */
 392         message_to_share_mode_entry(&msg, (char *)data->data);
 393
 394         DEBUG(10, ("Got oplock async level 2 break message from pid %d: %s/%lu\n",
 395                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 396
 397         fsp = initial_break_processing(msg.id, msg.share_file_id);
 398
 399         if (fsp == NULL) {
 400                 /* We hit a race here. Break messages are sent, and before we
 401                  * get to process this message, we have closed the file.
 402                  * No need to reply as this is an async message. */
 403                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 404                 return;
 405         }
 406
 407         if (fsp->oplock_type == NO_OPLOCK) {
 408                 /* We already got a "break to none" message and we've handled it.
 409                  * just ignore. */
 410                 DEBUG(3, ("process_oplock_async_level2_break_message: already broken to none, ignoring.\n"));
 411                 return;
 412         }
 413
 414         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 415                 /* Don't tell the client, just downgrade. */
 416                 DEBUG(3, ("process_oplock_async_level2_break_message: downgrading fake level 2 oplock.\n"));
 417                 remove_oplock(fsp);
 418                 return;
 419         }
 420
 421         /* Ensure we're really at level2 state. */
 422         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 423
 424         DEBUG(10,("process_oplock_async_level2_break_message: sending break to "
 425                 "none message for fid %d, file %s\n",
 426                 fsp->fnum,
 427                 fsp->fsp_name));
 428
 429         /* Now send a break to none message to our client. */
 430
 431         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 432         if (break_msg == NULL) {
 433                 exit_server("Could not talloc break_msg\n");
 434         }
 435
 436         /* Need to wait before sending a break message if we sent ourselves this message. */
 437         if (procid_to_pid(&src) == sys_getpid()) {
 438                 wait_before_sending_break();
 439         }
 440
 441         /* Save the server smb signing state. */
 442         sign_state = srv_oplock_set_signing(False);
 443
 444         show_msg(break_msg);
 445         if (!srv_send_smb(smbd_server_fd(),
 446                         break_msg,
 447                         IS_CONN_ENCRYPTED(fsp->conn))) {
 448                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 449         }
 450
 451         /* Restore the sign state to what it was. */
 452         srv_oplock_set_signing(sign_state);
 453
 454         TALLOC_FREE(break_msg);
 455
 456         /* Async level2 request, don't send a reply, just remove the oplock. */
 457         remove_oplock(fsp);
 458 }
 459
 460 /*******************************************************************
 461  This handles the generic oplock break message from another smbd.
 462 *******************************************************************/
 463
 464 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 465                                          void *private_data,
 466                                          uint32_t msg_type,
 467                                          struct server_id src,
 468                                          DATA_BLOB *data)
 469 {
 470         struct share_mode_entry msg;
 471         files_struct *fsp;
 472         char *break_msg;
 473         bool break_to_level2 = False;
 474         bool sign_state;
 475
 476         if (data->data == NULL) {
 477                 DEBUG(0, ("Got NULL buffer\n"));
 478                 return;
 479         }
 480
 481         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 482                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 483                 return;
 484         }
 485
 486         /* De-linearize incoming message. */
 487         message_to_share_mode_entry(&msg, (char *)data->data);
 488
 489         DEBUG(10, ("Got oplock break message from pid %d: %s/%lu\n",
 490                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
 491
 492         fsp = initial_break_processing(msg.id, msg.share_file_id);
 493
 494         if (fsp == NULL) {
 495                 /* a We hit race here. Break messages are sent, and before we
 496                  * get to process this message, we have closed the file. Reply
 497                  * with 'ok, oplock broken' */
 498                 DEBUG(3, ("Did not find fsp\n"));
 499
 500                 /* We just send the same message back. */
 501                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 502                                    (uint8 *)data->data,
 503                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 504                 return;
 505         }
 506
 507         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 508                 /* Remember we have to inform the requesting PID when the
 509                  * client replies */
 510                 msg.pid = src;
 511                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 512                              &fsp->pending_break_messages,
 513                              &fsp->num_pending_break_messages);
 514                 return;
 515         }
 516
 517         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 518             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 519                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 520                           file_id_string_tos(&fsp->file_id),
 521                           fsp->fsp_name));
 522                 /* We just send the same message back. */
 523                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 524                                    (uint8 *)data->data,
 525                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 526                 return;
 527         }
 528
 529         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 530             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 531             !koplocks && /* NOTE: we force levelII off for kernel oplocks -
 532                           * this will change when it is supported */
 533             lp_level2_oplocks(SNUM(fsp->conn))) {
 534                 break_to_level2 = True;
 535         }
 536
 537         break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
 538                                           OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 539         if (break_msg == NULL) {
 540                 exit_server("Could not talloc break_msg\n");
 541         }
 542
 543         /* Need to wait before sending a break message if we sent ourselves this message. */
 544         if (procid_to_pid(&src) == sys_getpid()) {
 545                 wait_before_sending_break();
 546         }
 547
 548         /* Save the server smb signing state. */
 549         sign_state = srv_oplock_set_signing(False);
 550
 551         show_msg(break_msg);
 552         if (!srv_send_smb(smbd_server_fd(),
 553                         break_msg,
 554                         IS_CONN_ENCRYPTED(fsp->conn))) {
 555                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 556         }
 557
 558         /* Restore the sign state to what it was. */
 559         srv_oplock_set_signing(sign_state);
 560
 561         TALLOC_FREE(break_msg);
 562
 563         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 564
 565         msg.pid = src;
 566         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 567                      &fsp->pending_break_messages,
 568                      &fsp->num_pending_break_messages);
 569
 570         add_oplock_timeout_handler(fsp);
 571 }
 572
 573 /*******************************************************************
 574  This handles the kernel oplock break message.
 575 *******************************************************************/
 576
 577 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 578                                         void *private_data,
 579                                         uint32_t msg_type,
 580                                         struct server_id src,
 581                                         DATA_BLOB *data)
 582 {
 583         struct file_id id;
 584         unsigned long file_id;
 585         files_struct *fsp;
 586         char *break_msg;
 587         bool sign_state;
 588
 589         if (data->data == NULL) {
 590                 DEBUG(0, ("Got NULL buffer\n"));
 591                 return;
 592         }
 593
 594         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 595                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 596                 return;
 597         }
 598
 599         /* Pull the data from the message. */
 600         pull_file_id_16((char *)data->data, &id);
 601         file_id = (unsigned long)IVAL(data->data, 16);
 602
 603         DEBUG(10, ("Got kernel oplock break message from pid %d: %s/%u\n",
 604                    (int)procid_to_pid(&src), file_id_string_tos(&id),
 605                    (unsigned int)file_id));
 606
 607         fsp = initial_break_processing(id, file_id);
 608
 609         if (fsp == NULL) {
 610                 DEBUG(3, ("Got a kernel oplock break message for a file "
 611                           "I don't know about\n"));
 612                 return;
 613         }
 614
 615         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 616                 /* This is ok, kernel oplocks come in completely async */
 617                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 618                           "break reply\n"));
 619                 return;
 620         }
 621
 622         break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
 623         if (break_msg == NULL) {
 624                 exit_server("Could not talloc break_msg\n");
 625         }
 626
 627         /* Save the server smb signing state. */
 628         sign_state = srv_oplock_set_signing(False);
 629
 630         show_msg(break_msg);
 631         if (!srv_send_smb(smbd_server_fd(),
 632                         break_msg,
 633                         IS_CONN_ENCRYPTED(fsp->conn))) {
 634                 exit_server_cleanly("oplock_break: srv_send_smb failed.");
 635         }
 636
 637         /* Restore the sign state to what it was. */
 638         srv_oplock_set_signing(sign_state);
 639
 640         TALLOC_FREE(break_msg);
 641
 642         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 643
 644         add_oplock_timeout_handler(fsp);
 645 }
 646
 647 void reply_to_oplock_break_requests(files_struct *fsp)
 648 {
 649         int i;
 650
 651         for (i=0; i<fsp->num_pending_break_messages; i++) {
 652                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 653                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 654
 655                 share_mode_entry_to_message(msg, e);
 656
 657                 messaging_send_buf(smbd_messaging_context(), e->pid,
 658                                    MSG_SMB_BREAK_RESPONSE,
 659                                    (uint8 *)msg,
 660                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 661         }
 662
 663         SAFE_FREE(fsp->pending_break_messages);
 664         fsp->num_pending_break_messages = 0;
 665         if (fsp->oplock_timeout != NULL) {
 666                 /* Remove the timed event handler. */
 667                 TALLOC_FREE(fsp->oplock_timeout);
 668                 fsp->oplock_timeout = NULL;
 669         }
 670         return;
 671 }
 672
 673 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 674                                           void *private_data,
 675                                           uint32_t msg_type,
 676                                           struct server_id src,
 677                                           DATA_BLOB *data)
 678 {
 679         struct share_mode_entry msg;
 680
 681         if (data->data == NULL) {
 682                 DEBUG(0, ("Got NULL buffer\n"));
 683                 return;
 684         }
 685
 686         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 687                 DEBUG(0, ("Got invalid msg len %u\n",
 688                           (unsigned int)data->length));
 689                 return;
 690         }
 691
 692         /* De-linearize incoming message. */
 693         message_to_share_mode_entry(&msg, (char *)data->data);
 694
 695         DEBUG(10, ("Got oplock break response from pid %d: %s/%lu mid %u\n",
 696                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id,
 697                    (unsigned int)msg.op_mid));
 698
 699         /* Here's the hack from open.c, store the mid in the 'port' field */
 700         schedule_deferred_open_smb_message(msg.op_mid);
 701 }
 702
 703 static void process_open_retry_message(struct messaging_context *msg_ctx,
 704                                        void *private_data,
 705                                        uint32_t msg_type,
 706                                        struct server_id src,
 707                                        DATA_BLOB *data)
 708 {
 709         struct share_mode_entry msg;
 710
 711         if (data->data == NULL) {
 712                 DEBUG(0, ("Got NULL buffer\n"));
 713                 return;
 714         }
 715
 716         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 717                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 718                 return;
 719         }
 720
 721         /* De-linearize incoming message. */
 722         message_to_share_mode_entry(&msg, (char *)data->data);
 723
 724         DEBUG(10, ("Got open retry msg from pid %d: %s mid %u\n",
 725                    (int)procid_to_pid(&src), file_id_string_tos(&msg.id),
 726                    (unsigned int)msg.op_mid));
 727
 728         schedule_deferred_open_smb_message(msg.op_mid);
 729 }
 730
 731 /****************************************************************************
 732  This function is called on any file modification or lock request. If a file
 733  is level 2 oplocked then it must tell all other level 2 holders to break to
 734  none.
 735 ****************************************************************************/
 736
 737 void release_level_2_oplocks_on_change(files_struct *fsp)
 738 {
 739         int i;
 740         struct share_mode_lock *lck;
 741
 742         /*
 743          * If this file is level II oplocked then we need
 744          * to grab the shared memory lock and inform all
 745          * other files with a level II lock that they need
 746          * to flush their read caches. We keep the lock over
 747          * the shared memory area whilst doing this.
 748          */
 749
 750         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 751                 return;
 752
 753         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 754                                   NULL);
 755         if (lck == NULL) {
 756                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 757                          "share mode entry for file %s.\n", fsp->fsp_name ));
 758                 return;
 759         }
 760
 761         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 762                   lck->num_share_modes ));
 763
 764         for(i = 0; i < lck->num_share_modes; i++) {
 765                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 766                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 767
 768                 if (!is_valid_share_mode_entry(share_entry)) {
 769                         continue;
 770                 }
 771
 772                 /*
 773                  * As there could have been multiple writes waiting at the
 774                  * lock_share_entry gate we may not be the first to
 775                  * enter. Hence the state of the op_types in the share mode
 776                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 777                  * oplock. It will do no harm to re-send break messages to
 778                  * those smbd's that are still waiting their turn to remove
 779                  * their LEVEL_II state, and also no harm to ignore existing
 780                  * NO_OPLOCK states. JRA.
 781                  */
 782
 783                 DEBUG(10,("release_level_2_oplocks_on_change: "
 784                           "share_entry[%i]->op_type == %d\n",
 785                           i, share_entry->op_type ));
 786
 787                 if (share_entry->op_type == NO_OPLOCK) {
 788                         continue;
 789                 }
 790
 791                 /* Paranoia .... */
 792                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 793                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 794                                  "share mode entry %d is an exlusive "
 795                                  "oplock !\n", i ));
 796                         TALLOC_FREE(lck);
 797                         abort();
 798                 }
 799
 800                 share_mode_entry_to_message(msg, share_entry);
 801
 802                 /*
 803                  * Deal with a race condition when breaking level2
 804                  * oplocks. Don't send all the messages and release
 805                  * the lock, this allows someone else to come in and
 806                  * get a level2 lock before any of the messages are
 807                  * processed, and thus miss getting a break message.
 808                  * Ensure at least one entry (the one we're breaking)
 809                  * is processed immediately under the lock and becomes
 810                  * set as NO_OPLOCK to stop any waiter getting a level2.
 811                  * Bugid #5980.
 812                  */
 813
 814                 if (procid_is_me(&share_entry->pid)) {
 815                         DATA_BLOB blob = data_blob_const(msg,
 816                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 817                         process_oplock_async_level2_break_message(smbd_messaging_context(),
 818                                                 NULL,
 819                                                 MSG_SMB_ASYNC_LEVEL2_BREAK,
 820                                                 share_entry->pid,
 821                                                 &blob);
 822                 } else {
 823                         messaging_send_buf(smbd_messaging_context(),
 824                                         share_entry->pid,
 825                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 826                                         (uint8 *)msg,
 827                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 828                 }
 829         }
 830
 831         /* We let the message receivers handle removing the oplock state
 832            in the share mode lock db. */
 833
 834         TALLOC_FREE(lck);
 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,0,(uint32)e->pid.pid);
 844         SSVAL(msg,4,e->op_mid);
 845         SSVAL(msg,6,e->op_type);
 846         SIVAL(msg,8,e->access_mask);
 847         SIVAL(msg,12,e->share_access);
 848         SIVAL(msg,16,e->private_options);
 849         SIVAL(msg,20,(uint32)e->time.tv_sec);
 850         SIVAL(msg,24,(uint32)e->time.tv_usec);
 851         push_file_id_16(msg+28, &e->id);
 852         SIVAL(msg,44,e->share_file_id);
 853         SIVAL(msg,48,e->uid);
 854         SSVAL(msg,52,e->flags);
 855 #ifdef CLUSTER_SUPPORT
 856         SIVAL(msg,54,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,0);
 867         e->op_mid = SVAL(msg,4);
 868         e->op_type = SVAL(msg,6);
 869         e->access_mask = IVAL(msg,8);
 870         e->share_access = IVAL(msg,12);
 871         e->private_options = IVAL(msg,16);
 872         e->time.tv_sec = (time_t)IVAL(msg,20);
 873         e->time.tv_usec = (int)IVAL(msg,24);
 874         pull_file_id_16(msg+28, &e->id);
 875         e->share_file_id = (unsigned long)IVAL(msg,44);
 876         e->uid = (uint32)IVAL(msg,48);
 877         e->flags = (uint16)SVAL(msg,52);
 878 #ifdef CLUSTER_SUPPORT
 879         e->pid.vnn = IVAL(msg,54);
 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 #endif
 908         }
 909
 910         return True;
 911 }