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  Get the number of current exclusive oplocks.
  31 ****************************************************************************/
  32
  33 int32 get_number_of_exclusive_open_oplocks(void)
  34 {
  35   return exclusive_oplocks_open;
  36 }
  37
  38 /*
  39  * helper function used by the kernel oplock backends to post the break message
  40  */
  41 void break_kernel_oplock(struct messaging_context *msg_ctx, files_struct *fsp)
  42 {
  43         uint8_t msg[MSG_SMB_KERNEL_BREAK_SIZE];
  44
  45         /* Put the kernel break info into the message. */
  46         push_file_id_24((char *)msg, &fsp->file_id);
  47         SIVAL(msg,24,fsp->fh->gen_id);
  48
  49         /* Don't need to be root here as we're only ever
  50            sending to ourselves. */
  51
  52         messaging_send_buf(msg_ctx, messaging_server_id(msg_ctx),
  53                            MSG_SMB_KERNEL_BREAK,
  54                            msg, MSG_SMB_KERNEL_BREAK_SIZE);
  55 }
  56
  57 /****************************************************************************
  58  Attempt to set an oplock on a file. Succeeds if kernel oplocks are
  59  disabled (just sets flags) and no byte-range locks in the file. Returns True
  60  if oplock set.
  61 ****************************************************************************/
  62
  63 bool set_file_oplock(files_struct *fsp, int oplock_type)
  64 {
  65         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
  66                 if (koplocks &&
  67                     !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) {
  68                         DEBUG(10, ("Refusing level2 oplock, kernel oplocks "
  69                                    "don't support them\n"));
  70                         return false;
  71                 }
  72         }
  73
  74         if ((fsp->oplock_type != NO_OPLOCK) &&
  75             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
  76             koplocks &&
  77             !koplocks->ops->set_oplock(koplocks, fsp, oplock_type)) {
  78                 return False;
  79         }
  80
  81         fsp->oplock_type = oplock_type;
  82         fsp->sent_oplock_break = NO_BREAK_SENT;
  83         if (oplock_type == LEVEL_II_OPLOCK) {
  84                 level_II_oplocks_open++;
  85         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
  86                 exclusive_oplocks_open++;
  87         }
  88
  89         DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
  90                     "tv_sec = %x, tv_usec = %x\n",
  91                  fsp_str_dbg(fsp), file_id_string_tos(&fsp->file_id),
  92                  fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
  93                  (int)fsp->open_time.tv_usec ));
  94
  95         return True;
  96 }
  97
  98 /****************************************************************************
  99  Attempt to release an oplock on a file. Decrements oplock count.
 100 ****************************************************************************/
 101
 102 void release_file_oplock(files_struct *fsp)
 103 {
 104         if ((fsp->oplock_type != NO_OPLOCK) &&
 105             (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 106             koplocks) {
 107                 koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 108         }
 109
 110         if (fsp->oplock_type == LEVEL_II_OPLOCK) {
 111                 level_II_oplocks_open--;
 112         } else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 113                 exclusive_oplocks_open--;
 114         }
 115
 116         SMB_ASSERT(exclusive_oplocks_open>=0);
 117         SMB_ASSERT(level_II_oplocks_open>=0);
 118
 119         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 120                 /* This doesn't matter for close. */
 121                 fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
 122         } else {
 123                 fsp->oplock_type = NO_OPLOCK;
 124         }
 125         fsp->sent_oplock_break = NO_BREAK_SENT;
 126
 127         flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
 128         delete_write_cache(fsp);
 129
 130         TALLOC_FREE(fsp->oplock_timeout);
 131 }
 132
 133 /****************************************************************************
 134  Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
 135 ****************************************************************************/
 136
 137 static void downgrade_file_oplock(files_struct *fsp)
 138 {
 139         if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 140                 DEBUG(0, ("trying to downgrade an already-downgraded oplock!\n"));
 141                 return;
 142         }
 143
 144         if (koplocks) {
 145                 koplocks->ops->release_oplock(koplocks, fsp, LEVEL_II_OPLOCK);
 146         }
 147         fsp->oplock_type = LEVEL_II_OPLOCK;
 148         exclusive_oplocks_open--;
 149         level_II_oplocks_open++;
 150         fsp->sent_oplock_break = NO_BREAK_SENT;
 151 }
 152
 153 /****************************************************************************
 154  Remove a file oplock. Copes with level II and exclusive.
 155  Locks then unlocks the share mode lock. Client can decide to go directly
 156  to none even if a "break-to-level II" was sent.
 157 ****************************************************************************/
 158
 159 bool remove_oplock(files_struct *fsp)
 160 {
 161         bool ret;
 162         struct share_mode_lock *lck;
 163
 164         /* Remove the oplock flag from the sharemode. */
 165         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 166                                   NULL);
 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         ret = remove_share_oplock(lck, fsp);
 173         if (!ret) {
 174                 DEBUG(0,("remove_oplock: failed to remove share oplock for "
 175                          "file %s fnum %d, %s\n",
 176                          fsp_str_dbg(fsp), fsp->fnum,
 177                          file_id_string_tos(&fsp->file_id)));
 178         }
 179         release_file_oplock(fsp);
 180         TALLOC_FREE(lck);
 181         return ret;
 182 }
 183
 184 /*
 185  * Deal with a reply when a break-to-level II was sent.
 186  */
 187 bool downgrade_oplock(files_struct *fsp)
 188 {
 189         bool ret;
 190         struct share_mode_lock *lck;
 191
 192         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 193                                   NULL);
 194         if (lck == NULL) {
 195                 DEBUG(0,("downgrade_oplock: failed to lock share entry for "
 196                          "file %s\n", fsp_str_dbg(fsp)));
 197                 return False;
 198         }
 199         ret = downgrade_share_oplock(lck, fsp);
 200         if (!ret) {
 201                 DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
 202                          "for file %s fnum %d, file_id %s\n",
 203                          fsp_str_dbg(fsp), fsp->fnum,
 204                          file_id_string_tos(&fsp->file_id)));
 205         }
 206
 207         downgrade_file_oplock(fsp);
 208         TALLOC_FREE(lck);
 209         return ret;
 210 }
 211
 212 /*
 213  * Some kernel oplock implementations handle the notification themselves.
 214  */
 215 bool should_notify_deferred_opens()
 216 {
 217         return !(koplocks &&
 218                 (koplocks->flags & KOPLOCKS_DEFERRED_OPEN_NOTIFICATION));
 219 }
 220
 221 /****************************************************************************
 222  Set up an oplock break message.
 223 ****************************************************************************/
 224
 225 static char *new_break_message_smb1(TALLOC_CTX *mem_ctx,
 226                                    files_struct *fsp, int cmd)
 227 {
 228         char *result = talloc_array(mem_ctx, char, smb_size + 8*2 + 0);
 229
 230         if (result == NULL) {
 231                 DEBUG(0, ("talloc failed\n"));
 232                 return NULL;
 233         }
 234
 235         memset(result,'\0',smb_size);
 236         srv_set_message(result,8,0,true);
 237         SCVAL(result,smb_com,SMBlockingX);
 238         SSVAL(result,smb_tid,fsp->conn->cnum);
 239         SSVAL(result,smb_pid,0xFFFF);
 240         SSVAL(result,smb_uid,0);
 241         SSVAL(result,smb_mid,0xFFFF);
 242         SCVAL(result,smb_vwv0,0xFF);
 243         SSVAL(result,smb_vwv2,fsp->fnum);
 244         SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
 245         SCVAL(result,smb_vwv3+1,cmd);
 246         return result;
 247 }
 248
 249 /****************************************************************************
 250  Function to do the waiting before sending a local break.
 251 ****************************************************************************/
 252
 253 static void wait_before_sending_break(void)
 254 {
 255         long wait_time = (long)lp_oplock_break_wait_time();
 256
 257         if (wait_time) {
 258                 smb_msleep(wait_time);
 259         }
 260 }
 261
 262 /****************************************************************************
 263  Ensure that we have a valid oplock.
 264 ****************************************************************************/
 265
 266 static files_struct *initial_break_processing(
 267         struct smbd_server_connection *sconn, struct file_id id,
 268         unsigned long file_id)
 269 {
 270         files_struct *fsp = NULL;
 271
 272         if( DEBUGLVL( 3 ) ) {
 273                 dbgtext( "initial_break_processing: called for %s/%u\n",
 274                          file_id_string_tos(&id), (int)file_id);
 275                 dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
 276                         exclusive_oplocks_open, level_II_oplocks_open );
 277         }
 278
 279         /*
 280          * We need to search the file open table for the
 281          * entry containing this dev and inode, and ensure
 282          * we have an oplock on it.
 283          */
 284
 285         fsp = file_find_dif(sconn, id, file_id);
 286
 287         if(fsp == NULL) {
 288                 /* The file could have been closed in the meantime - return success. */
 289                 if( DEBUGLVL( 3 ) ) {
 290                         dbgtext( "initial_break_processing: cannot find open file with " );
 291                         dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
 292                         dbgtext( "allowing break to succeed.\n" );
 293                 }
 294                 return NULL;
 295         }
 296
 297         /* Ensure we have an oplock on the file */
 298
 299         /*
 300          * There is a potential race condition in that an oplock could
 301          * have been broken due to another udp request, and yet there are
 302          * still oplock break messages being sent in the udp message
 303          * queue for this file. So return true if we don't have an oplock,
 304          * as we may have just freed it.
 305          */
 306
 307         if(fsp->oplock_type == NO_OPLOCK) {
 308                 if( DEBUGLVL( 3 ) ) {
 309                         dbgtext( "initial_break_processing: file %s ",
 310                                  fsp_str_dbg(fsp));
 311                         dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
 312                                  file_id_string_tos(&id), fsp->fh->gen_id );
 313                         dbgtext( "Allowing break to succeed regardless.\n" );
 314                 }
 315                 return NULL;
 316         }
 317
 318         return fsp;
 319 }
 320
 321 static void oplock_timeout_handler(struct event_context *ctx,
 322                                    struct timed_event *te,
 323                                    struct timeval now,
 324                                    void *private_data)
 325 {
 326         files_struct *fsp = (files_struct *)private_data;
 327
 328         /* Remove the timed event handler. */
 329         TALLOC_FREE(fsp->oplock_timeout);
 330         DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n",
 331                   fsp_str_dbg(fsp)));
 332         remove_oplock(fsp);
 333         reply_to_oplock_break_requests(fsp);
 334 }
 335
 336 /*******************************************************************
 337  Add a timeout handler waiting for the client reply.
 338 *******************************************************************/
 339
 340 static void add_oplock_timeout_handler(files_struct *fsp)
 341 {
 342         /*
 343          * If kernel oplocks already notifies smbds when an oplock break times
 344          * out, just return.
 345          */
 346         if (koplocks &&
 347             (koplocks->flags & KOPLOCKS_TIMEOUT_NOTIFICATION)) {
 348                 return;
 349         }
 350
 351         if (fsp->oplock_timeout != NULL) {
 352                 DEBUG(0, ("Logic problem -- have an oplock event hanging "
 353                           "around\n"));
 354         }
 355
 356         fsp->oplock_timeout =
 357                 tevent_add_timer(fsp->conn->sconn->ev_ctx, fsp,
 358                                  timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
 359                                  oplock_timeout_handler, fsp);
 360
 361         if (fsp->oplock_timeout == NULL) {
 362                 DEBUG(0, ("Could not add oplock timeout handler\n"));
 363         }
 364 }
 365
 366 static void send_break_message_smb1(files_struct *fsp, int level)
 367 {
 368         char *break_msg = new_break_message_smb1(talloc_tos(),
 369                                         fsp,
 370                                         level);
 371         if (break_msg == NULL) {
 372                 exit_server("Could not talloc break_msg\n");
 373         }
 374
 375         show_msg(break_msg);
 376         if (!srv_send_smb(fsp->conn->sconn,
 377                         break_msg, false, 0,
 378                         IS_CONN_ENCRYPTED(fsp->conn),
 379                         NULL)) {
 380                 exit_server_cleanly("send_break_message_smb1: "
 381                         "srv_send_smb failed.");
 382         }
 383
 384         TALLOC_FREE(break_msg);
 385 }
 386
 387 void break_level2_to_none_async(files_struct *fsp)
 388 {
 389         struct smbd_server_connection *sconn = fsp->conn->sconn;
 390
 391         if (fsp->oplock_type == NO_OPLOCK) {
 392                 /* We already got a "break to none" message and we've handled
 393                  * it.  just ignore. */
 394                 DEBUG(3, ("process_oplock_async_level2_break_message: already "
 395                           "broken to none, ignoring.\n"));
 396                 return;
 397         }
 398
 399         if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
 400                 /* Don't tell the client, just downgrade. */
 401                 DEBUG(3, ("process_oplock_async_level2_break_message: "
 402                           "downgrading fake level 2 oplock.\n"));
 403                 remove_oplock(fsp);
 404                 return;
 405         }
 406
 407         /* Ensure we're really at level2 state. */
 408         SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 409
 410         DEBUG(10,("process_oplock_async_level2_break_message: sending break "
 411                   "to none message for fid %d, file %s\n", fsp->fnum,
 412                   fsp_str_dbg(fsp)));
 413
 414         /* Now send a break to none message to our client. */
 415         if (sconn->using_smb2) {
 416                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 417         } else {
 418                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 419         }
 420
 421         /* Async level2 request, don't send a reply, just remove the oplock. */
 422         remove_oplock(fsp);
 423 }
 424
 425 /*******************************************************************
 426  This handles the case of a write triggering a break to none
 427  message on a level2 oplock.
 428  When we get this message we may be in any of three states :
 429  NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
 430  the client for LEVEL2.
 431 *******************************************************************/
 432
 433 void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
 434                                                       void *private_data,
 435                                                       uint32_t msg_type,
 436                                                       struct server_id src,
 437                                                       DATA_BLOB *data)
 438 {
 439         struct share_mode_entry msg;
 440         files_struct *fsp;
 441         struct smbd_server_connection *sconn =
 442                 talloc_get_type_abort(private_data,
 443                 struct smbd_server_connection);
 444
 445         if (data->data == NULL) {
 446                 DEBUG(0, ("Got NULL buffer\n"));
 447                 return;
 448         }
 449
 450         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 451                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 452                 return;
 453         }
 454
 455         /* De-linearize incoming message. */
 456         message_to_share_mode_entry(&msg, (char *)data->data);
 457
 458         DEBUG(10, ("Got oplock async level 2 break message from pid %s: "
 459                    "%s/%llu\n", server_id_str(talloc_tos(), &src),
 460                    file_id_string_tos(&msg.id),
 461                    (unsigned long long)msg.share_file_id));
 462
 463         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 464
 465         if (fsp == NULL) {
 466                 /* We hit a race here. Break messages are sent, and before we
 467                  * get to process this message, we have closed the file.
 468                  * No need to reply as this is an async message. */
 469                 DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
 470                 return;
 471         }
 472
 473         break_level2_to_none_async(fsp);
 474 }
 475
 476 /*******************************************************************
 477  This handles the generic oplock break message from another smbd.
 478 *******************************************************************/
 479
 480 static void process_oplock_break_message(struct messaging_context *msg_ctx,
 481                                          void *private_data,
 482                                          uint32_t msg_type,
 483                                          struct server_id src,
 484                                          DATA_BLOB *data)
 485 {
 486         struct share_mode_entry msg;
 487         files_struct *fsp;
 488         bool break_to_level2 = False;
 489         struct smbd_server_connection *sconn =
 490                 talloc_get_type_abort(private_data,
 491                 struct smbd_server_connection);
 492
 493         if (data->data == NULL) {
 494                 DEBUG(0, ("Got NULL buffer\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/%llu\n",
 507                    server_id_str(talloc_tos(), &src),
 508                    file_id_string_tos(&msg.id),
 509                    (unsigned long long)msg.share_file_id));
 510
 511         fsp = initial_break_processing(sconn, msg.id, msg.share_file_id);
 512
 513         if (fsp == NULL) {
 514                 /* We hit a race here. Break messages are sent, and before we
 515                  * get to process this message, we have closed the file. Reply
 516                  * with 'ok, oplock broken' */
 517                 DEBUG(3, ("Did not find fsp\n"));
 518
 519                 /* We just send the same message back. */
 520                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 521                                    (uint8 *)data->data,
 522                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 523                 return;
 524         }
 525
 526         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 527                 /* Remember we have to inform the requesting PID when the
 528                  * client replies */
 529                 msg.pid = src;
 530                 ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 531                              &fsp->pending_break_messages,
 532                              &fsp->num_pending_break_messages);
 533                 return;
 534         }
 535
 536         if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
 537             !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 538                 DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 539                           file_id_string_tos(&fsp->file_id),
 540                           fsp_str_dbg(fsp)));
 541                 /* We just send the same message back. */
 542                 messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
 543                                    (uint8 *)data->data,
 544                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 545                 return;
 546         }
 547
 548         if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
 549             !(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
 550             !(koplocks && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 551             lp_level2_oplocks(SNUM(fsp->conn))) {
 552                 break_to_level2 = True;
 553         }
 554
 555         /* Need to wait before sending a break
 556            message if we sent ourselves this message. */
 557         if (procid_is_me(&src)) {
 558                 wait_before_sending_break();
 559         }
 560
 561         if (sconn->using_smb2) {
 562                 send_break_message_smb2(fsp, break_to_level2 ?
 563                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 564         } else {
 565                 send_break_message_smb1(fsp, break_to_level2 ?
 566                         OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
 567         }
 568
 569         fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
 570
 571         msg.pid = src;
 572         ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
 573                      &fsp->pending_break_messages,
 574                      &fsp->num_pending_break_messages);
 575
 576         add_oplock_timeout_handler(fsp);
 577 }
 578
 579 /*******************************************************************
 580  This handles the kernel oplock break message.
 581 *******************************************************************/
 582
 583 static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
 584                                         void *private_data,
 585                                         uint32_t msg_type,
 586                                         struct server_id src,
 587                                         DATA_BLOB *data)
 588 {
 589         struct file_id id;
 590         unsigned long file_id;
 591         files_struct *fsp;
 592         struct smbd_server_connection *sconn =
 593                 talloc_get_type_abort(private_data,
 594                 struct smbd_server_connection);
 595
 596         if (data->data == NULL) {
 597                 DEBUG(0, ("Got NULL buffer\n"));
 598                 return;
 599         }
 600
 601         if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
 602                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 603                 return;
 604         }
 605
 606         /* Pull the data from the message. */
 607         pull_file_id_24((char *)data->data, &id);
 608         file_id = (unsigned long)IVAL(data->data, 24);
 609
 610         DEBUG(10, ("Got kernel oplock break message from pid %s: %s/%u\n",
 611                    server_id_str(talloc_tos(), &src), file_id_string_tos(&id),
 612                    (unsigned int)file_id));
 613
 614         fsp = initial_break_processing(sconn, id, file_id);
 615
 616         if (fsp == NULL) {
 617                 DEBUG(3, ("Got a kernel oplock break message for a file "
 618                           "I don't know about\n"));
 619                 return;
 620         }
 621
 622         if (fsp->sent_oplock_break != NO_BREAK_SENT) {
 623                 /* This is ok, kernel oplocks come in completely async */
 624                 DEBUG(3, ("Got a kernel oplock request while waiting for a "
 625                           "break reply\n"));
 626                 return;
 627         }
 628
 629         if (sconn->using_smb2) {
 630                 send_break_message_smb2(fsp, OPLOCKLEVEL_NONE);
 631         } else {
 632                 send_break_message_smb1(fsp, OPLOCKLEVEL_NONE);
 633         }
 634
 635         fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
 636
 637         add_oplock_timeout_handler(fsp);
 638 }
 639
 640 void reply_to_oplock_break_requests(files_struct *fsp)
 641 {
 642         int i;
 643
 644         /*
 645          * If kernel oplocks already notifies smbds when oplocks are
 646          * broken/removed, just return.
 647          */
 648         if (koplocks &&
 649             (koplocks->flags & KOPLOCKS_OPLOCK_BROKEN_NOTIFICATION)) {
 650                 return;
 651         }
 652
 653         for (i=0; i<fsp->num_pending_break_messages; i++) {
 654                 struct share_mode_entry *e = &fsp->pending_break_messages[i];
 655                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 656
 657                 share_mode_entry_to_message(msg, e);
 658
 659                 messaging_send_buf(fsp->conn->sconn->msg_ctx, e->pid,
 660                                    MSG_SMB_BREAK_RESPONSE,
 661                                    (uint8 *)msg,
 662                                    MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 663         }
 664
 665         SAFE_FREE(fsp->pending_break_messages);
 666         fsp->num_pending_break_messages = 0;
 667         if (fsp->oplock_timeout != NULL) {
 668                 /* Remove the timed event handler. */
 669                 TALLOC_FREE(fsp->oplock_timeout);
 670                 fsp->oplock_timeout = NULL;
 671         }
 672         return;
 673 }
 674
 675 static void process_oplock_break_response(struct messaging_context *msg_ctx,
 676                                           void *private_data,
 677                                           uint32_t msg_type,
 678                                           struct server_id src,
 679                                           DATA_BLOB *data)
 680 {
 681         struct share_mode_entry msg;
 682         struct smbd_server_connection *sconn =
 683                 talloc_get_type_abort(private_data,
 684                 struct smbd_server_connection);
 685
 686         if (data->data == NULL) {
 687                 DEBUG(0, ("Got NULL buffer\n"));
 688                 return;
 689         }
 690
 691         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 692                 DEBUG(0, ("Got invalid msg len %u\n",
 693                           (unsigned int)data->length));
 694                 return;
 695         }
 696
 697         /* De-linearize incoming message. */
 698         message_to_share_mode_entry(&msg, (char *)data->data);
 699
 700         DEBUG(10, ("Got oplock break response from pid %s: %s/%llu mid %llu\n",
 701                    server_id_str(talloc_tos(), &src),
 702                    file_id_string_tos(&msg.id),
 703                    (unsigned long long)msg.share_file_id,
 704                    (unsigned long long)msg.op_mid));
 705
 706         schedule_deferred_open_message_smb(sconn, msg.op_mid);
 707 }
 708
 709 static void process_open_retry_message(struct messaging_context *msg_ctx,
 710                                        void *private_data,
 711                                        uint32_t msg_type,
 712                                        struct server_id src,
 713                                        DATA_BLOB *data)
 714 {
 715         struct share_mode_entry msg;
 716         struct smbd_server_connection *sconn =
 717                 talloc_get_type_abort(private_data,
 718                 struct smbd_server_connection);
 719
 720         if (data->data == NULL) {
 721                 DEBUG(0, ("Got NULL buffer\n"));
 722                 return;
 723         }
 724
 725         if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
 726                 DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
 727                 return;
 728         }
 729
 730         /* De-linearize incoming message. */
 731         message_to_share_mode_entry(&msg, (char *)data->data);
 732
 733         DEBUG(10, ("Got open retry msg from pid %s: %s mid %llu\n",
 734                    server_id_str(talloc_tos(), &src), file_id_string_tos(&msg.id),
 735                    (unsigned long long)msg.op_mid));
 736
 737         schedule_deferred_open_message_smb(sconn, msg.op_mid);
 738 }
 739
 740 /****************************************************************************
 741  This function is called on any file modification or lock request. If a file
 742  is level 2 oplocked then it must tell all other level 2 holders to break to
 743  none.
 744 ****************************************************************************/
 745
 746 static void contend_level2_oplocks_begin_default(files_struct *fsp,
 747                                               enum level2_contention_type type)
 748 {
 749         int i;
 750         struct share_mode_lock *lck;
 751
 752         /*
 753          * If this file is level II oplocked then we need
 754          * to grab the shared memory lock and inform all
 755          * other files with a level II lock that they need
 756          * to flush their read caches. We keep the lock over
 757          * the shared memory area whilst doing this.
 758          */
 759
 760         if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
 761                 return;
 762
 763         lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
 764                                   NULL);
 765         if (lck == NULL) {
 766                 DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
 767                          "share mode entry for file %s.\n", fsp_str_dbg(fsp)));
 768                 return;
 769         }
 770
 771         DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
 772                   lck->num_share_modes ));
 773
 774         for(i = 0; i < lck->num_share_modes; i++) {
 775                 struct share_mode_entry *share_entry = &lck->share_modes[i];
 776                 char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
 777
 778                 if (!is_valid_share_mode_entry(share_entry)) {
 779                         continue;
 780                 }
 781
 782                 /*
 783                  * As there could have been multiple writes waiting at the
 784                  * lock_share_entry gate we may not be the first to
 785                  * enter. Hence the state of the op_types in the share mode
 786                  * entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
 787                  * oplock. It will do no harm to re-send break messages to
 788                  * those smbd's that are still waiting their turn to remove
 789                  * their LEVEL_II state, and also no harm to ignore existing
 790                  * NO_OPLOCK states. JRA.
 791                  */
 792
 793                 DEBUG(10,("release_level_2_oplocks_on_change: "
 794                           "share_entry[%i]->op_type == %d\n",
 795                           i, share_entry->op_type ));
 796
 797                 if (share_entry->op_type == NO_OPLOCK) {
 798                         continue;
 799                 }
 800
 801                 /* Paranoia .... */
 802                 if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
 803                         DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
 804                                  "share mode entry %d is an exlusive "
 805                                  "oplock !\n", i ));
 806                         TALLOC_FREE(lck);
 807                         abort();
 808                 }
 809
 810                 share_mode_entry_to_message(msg, share_entry);
 811
 812                 /*
 813                  * Deal with a race condition when breaking level2
 814                  * oplocks. Don't send all the messages and release
 815                  * the lock, this allows someone else to come in and
 816                  * get a level2 lock before any of the messages are
 817                  * processed, and thus miss getting a break message.
 818                  * Ensure at least one entry (the one we're breaking)
 819                  * is processed immediately under the lock and becomes
 820                  * set as NO_OPLOCK to stop any waiter getting a level2.
 821                  * Bugid #5980.
 822                  */
 823
 824                 if (procid_is_me(&share_entry->pid)) {
 825                         struct files_struct *cur_fsp =
 826                                 initial_break_processing(fsp->conn->sconn,
 827                                         share_entry->id,
 828                                         share_entry->share_file_id);
 829                         wait_before_sending_break();
 830                         if (cur_fsp != NULL) {
 831                                 break_level2_to_none_async(cur_fsp);
 832                         } else {
 833                                 DEBUG(3, ("release_level_2_oplocks_on_change: "
 834                                 "Did not find fsp, ignoring\n"));
 835                         }
 836                 } else {
 837                         messaging_send_buf(fsp->conn->sconn->msg_ctx,
 838                                         share_entry->pid,
 839                                         MSG_SMB_ASYNC_LEVEL2_BREAK,
 840                                         (uint8 *)msg,
 841                                         MSG_SMB_SHARE_MODE_ENTRY_SIZE);
 842                 }
 843         }
 844
 845         /* We let the message receivers handle removing the oplock state
 846            in the share mode lock db. */
 847
 848         TALLOC_FREE(lck);
 849 }
 850
 851 void smbd_contend_level2_oplocks_begin(files_struct *fsp,
 852                                   enum level2_contention_type type)
 853 {
 854         if (koplocks && koplocks->ops->contend_level2_oplocks_begin) {
 855                 koplocks->ops->contend_level2_oplocks_begin(fsp, type);
 856                 return;
 857         }
 858
 859         contend_level2_oplocks_begin_default(fsp, type);
 860 }
 861
 862 void smbd_contend_level2_oplocks_end(files_struct *fsp,
 863                                 enum level2_contention_type type)
 864 {
 865         /* Only kernel oplocks implement this so far */
 866         if (koplocks && koplocks->ops->contend_level2_oplocks_end) {
 867                 koplocks->ops->contend_level2_oplocks_end(fsp, type);
 868         }
 869 }
 870
 871 /****************************************************************************
 872  Linearize a share mode entry struct to an internal oplock break message.
 873 ****************************************************************************/
 874
 875 void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
 876 {
 877         SIVAL(msg,OP_BREAK_MSG_PID_OFFSET,(uint32)e->pid.pid);
 878         SBVAL(msg,OP_BREAK_MSG_MID_OFFSET,e->op_mid);
 879         SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET,e->op_type);
 880         SIVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET,e->access_mask);
 881         SIVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET,e->share_access);
 882         SIVAL(msg,OP_BREAK_MSG_PRIV_OFFSET,e->private_options);
 883         SIVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET,(uint32_t)e->time.tv_sec);
 884         SIVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET,(uint32_t)e->time.tv_usec);
 885         push_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 886         SIVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET,e->share_file_id);
 887         SIVAL(msg,OP_BREAK_MSG_UID_OFFSET,e->uid);
 888         SSVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET,e->flags);
 889         SIVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET,e->name_hash);
 890         SIVAL(msg,OP_BREAK_MSG_VNN_OFFSET,e->pid.vnn);
 891 }
 892
 893 /****************************************************************************
 894  De-linearize an internal oplock break message to a share mode entry struct.
 895 ****************************************************************************/
 896
 897 void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
 898 {
 899         e->pid.pid = (pid_t)IVAL(msg,OP_BREAK_MSG_PID_OFFSET);
 900         e->op_mid = BVAL(msg,OP_BREAK_MSG_MID_OFFSET);
 901         e->op_type = SVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET);
 902         e->access_mask = IVAL(msg,OP_BREAK_MSG_ACCESS_MASK_OFFSET);
 903         e->share_access = IVAL(msg,OP_BREAK_MSG_SHARE_ACCESS_OFFSET);
 904         e->private_options = IVAL(msg,OP_BREAK_MSG_PRIV_OFFSET);
 905         e->time.tv_sec = (time_t)IVAL(msg,OP_BREAK_MSG_TIME_SEC_OFFSET);
 906         e->time.tv_usec = (int)IVAL(msg,OP_BREAK_MSG_TIME_USEC_OFFSET);
 907         pull_file_id_24(msg+OP_BREAK_MSG_DEV_OFFSET, &e->id);
 908         e->share_file_id = (unsigned long)IVAL(msg,OP_BREAK_MSG_FILE_ID_OFFSET);
 909         e->uid = (uint32)IVAL(msg,OP_BREAK_MSG_UID_OFFSET);
 910         e->flags = (uint16)SVAL(msg,OP_BREAK_MSG_FLAGS_OFFSET);
 911         e->name_hash = IVAL(msg,OP_BREAK_MSG_NAME_HASH_OFFSET);
 912         e->pid.vnn = IVAL(msg,OP_BREAK_MSG_VNN_OFFSET);
 913 }
 914
 915 /****************************************************************************
 916  Setup oplocks for this process.
 917 ****************************************************************************/
 918
 919 bool init_oplocks(struct smbd_server_connection *sconn)
 920 {
 921         DEBUG(3,("init_oplocks: initializing messages.\n"));
 922
 923         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_REQUEST,
 924                            process_oplock_break_message);
 925         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_ASYNC_LEVEL2_BREAK,
 926                            process_oplock_async_level2_break_message);
 927         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_BREAK_RESPONSE,
 928                            process_oplock_break_response);
 929         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_KERNEL_BREAK,
 930                            process_kernel_oplock_break);
 931         messaging_register(sconn->msg_ctx, sconn, MSG_SMB_OPEN_RETRY,
 932                            process_open_retry_message);
 933
 934         if (lp_kernel_oplocks()) {
 935 #if HAVE_KERNEL_OPLOCKS_IRIX
 936                 koplocks = irix_init_kernel_oplocks(sconn);
 937 #elif HAVE_KERNEL_OPLOCKS_LINUX
 938                 koplocks = linux_init_kernel_oplocks(sconn);
 939 #elif HAVE_ONEFS
 940 #error Isilon, please check if the NULL context is okay here. Thanks!
 941                 koplocks = onefs_init_kernel_oplocks(sconn);
 942 #endif
 943         }
 944
 945         return True;
 946 }