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, messaging_server_id(msg_ctx),
  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(
 260         struct smbd_server_connection *sconn, struct file_id id,
 261         unsigned long file_id)
 262 {
 263         files_struct *fsp = NULL;
 264
 265         if( DEBUGLVL( 3 ) ) {
 266                 dbgtext( "initial_break_processing: called for %s/%u\n",
 267                          file_id_string_tos(&id), (int)file_id);
 268                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 269                         exclusive_oplocks_open, level_II_oplocks_open );
 270         }
 271
 272         /*
 273          * We need to search the file open table for the
 274          * entry containing this dev and inode, and ensure
 275          * we have an oplock on it.
 276          */
 277
 278         fsp = file_find_dif(sconn, id, file_id);
 279
 280         if(fsp == NULL) {
 281                 /* The file could have been closed in the meantime - return success. */
 282                 if( DEBUGLVL( 3 ) ) {
 283                         dbgtext( "initial_break_processing: cannot find open file with " );
 284                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 285                         dbgtext( "allowing break to succeed.\n" );
 286                 }
 287                 return NULL;
 288         }
 289
 290         /* Ensure we have an oplock on the file */
 291
 292         /*
 293          * There is a potential race condition in that an oplock could
 294          * have been broken due to another udp request, and yet there are
 295          * still oplock break messages being sent in the udp message
 296          * queue for this file. So return true if we don't have an oplock,
 297          * as we may have just freed it.
 298          */
 299
 300         if(fsp->oplock_type == NO_OPLOCK) {
 301                 if( DEBUGLVL( 3 ) ) {
 302                         dbgtext( "initial_break_processing: file %s ",
 303                                  fsp_str_dbg(fsp));
 304                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 305                                  file_id_string_tos(&id), fsp->fh->gen_id );
 306                         dbgtext( "Allowing break to succeed regardless.\n" );
 307                 }
 308                 return NULL;
 309         }
 310
 311         return fsp;
 312 }
 313
 314 static void oplock_timeout_handler(struct event_context *ctx,
 315                                    struct timed_event *te,
 316                                    struct timeval now,
 317                                    void *private_data)
 318 {
 319         files_struct *fsp = (files_struct *)private_data;
 320
 321         /* Remove the timed event handler. */
 322         TALLOC_FREE(fsp->oplock_timeout);
 323         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 324                   fsp_str_dbg(fsp)));
 325         remove_oplock(fsp);
 326         reply_to_oplock_break_requests(fsp);
 327 }
 328
 329 /*******************************************************************
 330  Add a timeout handler waiting for the client reply.
 331 *******************************************************************/
 332
 333 static void add_oplock_timeout_handler(files_struct *fsp)
 334 {
 335         /*
 336          * If kernel oplocks already notifies smbds when an oplock break times
 337          * out, just return.
 338          */
 339         if (koplocks &&
 340             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 341                 return;
 342         }
 343
 344         if (fsp->oplock_timeout != NULL) {
 345                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 346                           "around\n"));
 347         }
 348
 349         fsp->oplock_timeout =
 350                 event_add_timed(smbd_event_context(), fsp,
 351                                 timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 352                                 oplock_timeout_handler, fsp);
 353
 354         if (fsp->oplock_timeout == NULL) {
 355                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 356         }
 357 }
 358
 359 static void send_break_message_smb1(files_struct *fsp, int level)
 360 {
 361         char *break_msg = new_break_message_smb1(talloc_tos(),
 362                                         fsp,
 363                                         level);
 364         if (break_msg == NULL) {
 365                 exit_server("Could not talloc break_msg\n");
 366         }
 367
 368         show_msg(break_msg);
 369         if (!srv_send_smb(fsp->conn->sconn,
 370                         break_msg, false, 0,
 371                         IS_CONN_ENCRYPTED(fsp->conn),
 372                         NULL)) {
 373                 exit_server_cleanly("send_break_message_smb1: "
 374                         "srv_send_smb failed.");
 375         }
 376
 377         TALLOC_FREE(break_msg);
 378 }
 379
 380 void break_level2_to_none_async(files_struct *fsp)
 381 {
 382         struct smbd_server_connection *sconn = fsp->conn->sconn;
 383
 384         if (fsp->oplock_type == NO_OPLOCK) {
 385                 /* We already got a "break to none" message and we've handled
 386                  * it.  just ignore. */
 387                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 388                           "broken to none, ignoring.\n"));
 389                 return;
 390         }
 391
 392         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 393                 /* Don't tell the client, just downgrade. */
 394                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 395                           "downgrading fake level 2 oplock.\n"));
 396                 remove_oplock(fsp);
 397                 return;
 398         }
 399
 400         /* Ensure we're really at level2 state. */
 401         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 402
 403         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 404                   "to none message for fid %d, file %s\n", fsp->fnum,
 405                   fsp_str_dbg(fsp)));
 406
 407         /* Now send a break to none message to our client. */
 408         if (sconn->using_smb2) {
 409                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 410         } else {
 411                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 412         }
 413
 414         /* Async level2 request, don't send a reply, just remove the oplock. */
 415         remove_oplock(fsp);
 416 }
 417
 418 /*******************************************************************
 419  This handles the case of a write triggering a break to none
 420  message on a level2 oplock.
 421  When we get this message we may be in any of three states :
 422  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 423  the client for LEVEL2.
 424 *******************************************************************/
 425
 426 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 427                                                       void *private_data,
 428                                                       uint32_t msg_type,
 429                                                       struct server_id src,
 430                                                       DATA_BLOB *data)
 431 {
 432         struct smbd_server_connection *sconn;
 433         struct share_mode_entry msg;
 434         files_struct *fsp;
 435
 436         if (data->data == NULL) {
 437                 DEBUG(0, ("Got NULL buffer\n"));
 438                 return;
 439         }
 440
 441         sconn = msg_ctx_to_sconn(msg_ctx);
 442         if (sconn == NULL) {
 443                 DEBUG(1, ("could not find sconn\n"));
 444                 return;
 445         }
 446
 447         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 448                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 449                 return;
 450         }
 451
 452         /* De-linearize incoming message. */
 453         message_to_share_mode_entry(&msg, (char *)data->data);
 454
 455         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 456                    "%s/%lu\n", procid_str(talloc_tos(), &src),
 457                    file_id_string_tos(&msg.id), msg.share_file_id));
 458
 459         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 460
 461         if (fsp == NULL) {
 462                 /* We hit a race here. Break messages are sent, and before we
 463                  * get to process this message, we have closed the file.
 464                  * No need to reply as this is an async message. */
 465                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 466                 return;
 467         }
 468
 469         break_level2_to_none_async(fsp);
 470 }
 471
 472 /*******************************************************************
 473  This handles the generic oplock break message from another smbd.
 474 *******************************************************************/
 475
 476 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 477                                          void *private_data,
 478                                          uint32_t msg_type,
 479                                          struct server_id src,
 480                                          DATA_BLOB *data)
 481 {
 482         struct smbd_server_connection *sconn;
 483         struct share_mode_entry msg;
 484         files_struct *fsp;
 485         bool break_to_level2 = False;
 486
 487         if (data->data == NULL) {
 488                 DEBUG(0, ("Got NULL buffer\n"));
 489                 return;
 490         }
 491
 492         sconn = msg_ctx_to_sconn(msg_ctx);
 493         if (sconn == NULL) {
 494                 DEBUG(1, ("could not find sconn\n"));
 495                 return;
 496         }
 497
 498         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 499                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 500                 return;
 501         }
 502
 503         /* De-linearize incoming message. */
 504         message_to_share_mode_entry(&msg, (char *)data->data);
 505
 506         DEBUG(10, ("Got oplock break message from pid %s: %s/%lu\n",
 507                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 508                    msg.share_file_id));
 509
 510         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 511
 512         if (fsp == NULL) {
 513                 /* We hit a race here. Break messages are sent, and before we
 514                  * get to process this message, we have closed the file. Reply
 515                  * with 'ok, oplock broken' */
 516                 DEBUG(3, ("Did not find fsp\n"));
 517
 518                 /* We just send the same message back. */
 519                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 520                                    (uint8 *)data->data,
 521                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 522                 return;
 523         }
 524
 525         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 526                 /* Remember we have to inform the requesting PID when the
 527                  * client replies */
 528                 msg.pid = src;
 529                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 530                              &fsp->pending_break_messages,
 531                              &fsp->num_pending_break_messages);
 532                 return;
 533         }
 534
 535         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 536             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 537                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 538                           file_id_string_tos(&fsp->file_id),
 539                           fsp_str_dbg(fsp)));
 540                 /* We just send the same message back. */
 541                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 542                                    (uint8 *)data->data,
 543                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 544                 return;
 545         }
 546
 547         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 548             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 549             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 550             lp_level2_oplocks(SNUM(fsp->conn))) {
 551                 break_to_level2 = True;
 552         }
 553
 554         /* Need to wait before sending a break
 555            message if we sent ourselves this message. */
 556         if (procid_is_me(&src)) {
 557                 wait_before_sending_break();
 558         }
 559
 560         if (sconn->using_smb2) {
 561                 send_break_message_smb2(fsp, break_to_level2 ?
 562                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 563         } else {
 564                 send_break_message_smb1(fsp, break_to_level2 ?
 565                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 566         }
 567
 568         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 569
 570         msg.pid = src;
 571         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 572                      &fsp->pending_break_messages,
 573                      &fsp->num_pending_break_messages);
 574
 575         add_oplock_timeout_handler(fsp);
 576 }
 577
 578 /*******************************************************************
 579  This handles the kernel oplock break message.
 580 *******************************************************************/
 581
 582 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 583                                         void *private_data,
 584                                         uint32_t msg_type,
 585                                         struct server_id src,
 586                                         DATA_BLOB *data)
 587 {
 588         struct smbd_server_connection *sconn = smbd_server_conn;
 589         struct file_id id;
 590         unsigned long file_id;
 591         files_struct *fsp;
 592
 593         if (data->data == NULL) {
 594                 DEBUG(0, ("Got NULL buffer\n"));
 595                 return;
 596         }
 597
 598         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 599                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 600                 return;
 601         }
 602
 603         /* Pull the data from the message. */
 604         pull_file_id_24((char *)data->data, &id);
 605         file_id = (unsigned long)IVAL(data->data, 24);
 606
 607         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 608                    procid_str(talloc_tos(), &src), file_id_string_tos(&id),
 609                    (unsigned int)file_id));
 610
 611         fsp = initial_break_processing(smbd_server_conn, id, file_id);
 612
 613         if (fsp == NULL) {
 614                 DEBUG(3, ("Got a kernel oplock break message for a file "
 615                           "I don't know about\n"));
 616                 return;
 617         }
 618
 619         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 620                 /* This is ok, kernel oplocks come in completely async */
 621                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 622                           "break reply\n"));
 623                 return;
 624         }
 625
 626         if (sconn->using_smb2) {
 627                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 628         } else {
 629                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 630         }
 631
 632         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 633
 634         add_oplock_timeout_handler(fsp);
 635 }
 636
 637 void reply_to_oplock_break_requests(files_struct *fsp)
 638 {
 639         int i;
 640
 641         /*
 642          * If kernel oplocks already notifies smbds when oplocks are
 643          * broken/removed, just return.
 644          */
 645         if (koplocks &&
 646             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 647                 return;
 648         }
 649
 650         for (i=0; i<fsp->num_pending_break_messages; i++) {
 651                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 652                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 653
 654                 share_mode_entry_to_message(msg, e);
 655
 656                 messaging_send_buf(fsp->conn->sconn->msg_ctx, e->pid,
 657                                    MSG_SMB_BREAK_RESPONSE,
 658                                    (uint8 *)msg,
 659                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 660         }
 661
 662         SAFE_FREE(fsp->pending_break_messages);
 663         fsp->num_pending_break_messages = 0;
 664         if (fsp->oplock_timeout != NULL) {
 665                 /* Remove the timed event handler. */
 666                 TALLOC_FREE(fsp->oplock_timeout);
 667                 fsp->oplock_timeout = NULL;
 668         }
 669         return;
 670 }
 671
 672 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 673                                           void *private_data,
 674                                           uint32_t msg_type,
 675                                           struct server_id src,
 676                                           DATA_BLOB *data)
 677 {
 678         struct share_mode_entry msg;
 679
 680         if (data->data == NULL) {
 681                 DEBUG(0, ("Got NULL buffer\n"));
 682                 return;
 683         }
 684
 685         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 686                 DEBUG(0, ("Got invalid msg len %u\n",
 687                           (unsigned int)data->length));
 688                 return;
 689         }
 690
 691         /* De-linearize incoming message. */
 692         message_to_share_mode_entry(&msg, (char *)data->data);
 693
 694         DEBUG(10, ("Got oplock break response from pid %s: %s/%lu mid %llu\n",
 695                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 696                    msg.share_file_id, (unsigned long long)msg.op_mid));
 697
 698         schedule_deferred_open_message_smb(msg.op_mid);
 699 }
 700
 701 static void process_open_retry_message(struct messaging_context *msg_ctx,
 702                                        void *private_data,
 703                                        uint32_t msg_type,
 704                                        struct server_id src,
 705                                        DATA_BLOB *data)
 706 {
 707         struct share_mode_entry msg;
 708
 709         if (data->data == NULL) {
 710                 DEBUG(0, ("Got NULL buffer\n"));
 711                 return;
 712         }
 713
 714         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 715                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 716                 return;
 717         }
 718
 719         /* De-linearize incoming message. */
 720         message_to_share_mode_entry(&msg, (char *)data->data);
 721
 722         DEBUG(10, ("Got open retry msg from pid %s: %s mid %llu\n",
 723                    procid_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 724                    (unsigned long long)msg.op_mid));
 725
 726         schedule_deferred_open_message_smb(msg.op_mid);
 727 }
 728
 729 /****************************************************************************
 730  This function is called on any file modification or lock request. If a file
 731  is level 2 oplocked then it must tell all other level 2 holders to break to
 732  none.
 733 ****************************************************************************/
 734
 735 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 736                                               enum level2_contention_type type)
 737 {
 738         int i;
 739         struct share_mode_lock *lck;
 740
 741         /*
 742          * If this file is level II oplocked then we need
 743          * to grab the shared memory lock and inform all
 744          * other files with a level II lock that they need
 745          * to flush their read caches. We keep the lock over
 746          * the shared memory area whilst doing this.
 747          */
 748
 749         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 750                 return;
 751
 752         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 753                                   NULL);
 754         if (lck == NULL) {
 755                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 756                          "share mode entry for file %s.\n", fsp_str_dbg(fsp)));
 757                 return;
 758         }
 759
 760         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 761                   lck->num_share_modes ));
 762
 763         for(i = 0; i < lck->num_share_modes; i++) {
 764                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 765                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 766
 767                 if (!is_valid_share_mode_entry(share_entry)) {
 768                         continue;
 769                 }
 770
 771                 /*
 772                  * As there could have been multiple writes waiting at the
 773                  * lock_share_entry gate we may not be the first to
 774                  * enter. Hence the state of the op_types in the share mode
 775                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 776                  * oplock. It will do no harm to re-send break messages to
 777                  * those smbd's that are still waiting their turn to remove
 778                  * their LEVEL_II state, and also no harm to ignore existing
 779                  * NO_OPLOCK states. JRA.
 780                  */
 781
 782                 DEBUG(10,("release_level_2_oplocks_on_change: "
 783                           "share_entry[%i]->op_type == %d\n",
 784                           i, share_entry->op_type ));
 785
 786                 if (share_entry->op_type == NO_OPLOCK) {
 787                         continue;
 788                 }
 789
 790                 /* Paranoia .... */
 791                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 792                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 793                                  "share mode entry %d is an exlusive "
 794                                  "oplock !\n", i ));
 795                         TALLOC_FREE(lck);
 796                         abort();
 797                 }
 798
 799                 share_mode_entry_to_message(msg, share_entry);
 800
 801                 /*
 802                  * Deal with a race condition when breaking level2
 803                  * oplocks. Don't send all the messages and release
 804                  * the lock, this allows someone else to come in and
 805                  * get a level2 lock before any of the messages are
 806                  * processed, and thus miss getting a break message.
 807                  * Ensure at least one entry (the one we're breaking)
 808                  * is processed immediately under the lock and becomes
 809                  * set as NO_OPLOCK to stop any waiter getting a level2.
 810                  * Bugid #5980.
 811                  */
 812
 813                 if (procid_is_me(&share_entry->pid)) {
 814                         wait_before_sending_break();
 815                         break_level2_to_none_async(fsp);
 816                 } else {
 817                         messaging_send_buf(fsp->conn->sconn->msg_ctx,
 818                                         share_entry->pid,
 819                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 820                                         (uint8 *)msg,
 821                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 822                 }
 823         }
 824
 825         /* We let the message receivers handle removing the oplock state
 826            in the share mode lock db. */
 827
 828         TALLOC_FREE(lck);
 829 }
 830
 831 void contend_level2_oplocks_begin(files_struct *fsp,
 832                                   enum level2_contention_type type)
 833 {
 834         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 835                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 836                 return;
 837         }
 838
 839         contend_level2_oplocks_begin_default(fsp, type);
 840 }
 841
 842 void contend_level2_oplocks_end(files_struct *fsp,
 843                                 enum level2_contention_type type)
 844 {
 845         /* Only kernel oplocks implement this so far */
 846         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 847                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 848         }
 849 }
 850
 851 /****************************************************************************
 852  Linearize a share mode entry struct to an internal oplock break message.
 853 ****************************************************************************/
 854
 855 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 856 {
 857         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 858         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 859         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 860         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 861         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 862         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 863         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 864         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 865         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 866         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 867         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 868         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 869 #ifdef CLUSTER_SUPPORT
 870         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 871 #endif
 872 }
 873
 874 /****************************************************************************
 875  De-linearize an internal oplock break message to a share mode entry struct.
 876 ****************************************************************************/
 877
 878 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 879 {
 880         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 881         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 882         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 883         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 884         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 885         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 886         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 887         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 888         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 889         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 890         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 891         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 892 #ifdef CLUSTER_SUPPORT
 893         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 894 #endif
 895 }
 896
 897 /****************************************************************************
 898  Setup oplocks for this process.
 899 ****************************************************************************/
 900
 901 bool init_oplocks(struct messaging_context *msg_ctx)
 902 {
 903         DEBUG(3,("init_oplocks: initializing messages.\n"));
 904
 905         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
 906                            process_oplock_break_message);
 907         messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
 908                            process_oplock_async_level2_break_message);
 909         messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
 910                            process_oplock_break_response);
 911         messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
 912                            process_kernel_oplock_break);
 913         messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
 914                            process_open_retry_message);
 915
 916         if (lp_kernel_oplocks()) {
 917 #if HAVE_KERNEL_OPLOCKS_IRIX
 918                 koplocks = irix_init_kernel_oplocks(talloc_autofree_context());
 919 #elif HAVE_KERNEL_OPLOCKS_LINUX
 920                 koplocks = linux_init_kernel_oplocks(talloc_autofree_context());
 921 #elif HAVE_ONEFS
 922                 koplocks = onefs_init_kernel_oplocks(talloc_autofree_context());
 923 #endif
 924         }
 925
 926         return True;
 927 }