source/smbd/fileio.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    read/write to a files_struct
   5    Copyright (C) Andrew Tridgell 1992-1998
   6    Copyright (C) Jeremy Allison 2000-2002. - write cache.
   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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24
  25 static BOOL setup_write_cache(files_struct *, SMB_OFF_T);
  26
  27 /****************************************************************************
  28  Seek a file. Try to avoid the seek if possible.
  29 ****************************************************************************/
  30
  31 static SMB_OFF_T seek_file(files_struct *fsp,SMB_OFF_T pos)
  32 {
  33         SMB_OFF_T seek_ret;
  34
  35         seek_ret = fsp->conn->vfs_ops.lseek(fsp,fsp->fd,pos,SEEK_SET);
  36
  37         if(seek_ret == -1) {
  38                 DEBUG(0,("seek_file: (%s) sys_lseek failed. Error was %s\n",
  39                         fsp->fsp_name, strerror(errno) ));
  40                 fsp->pos = -1;
  41                 return -1;
  42         }
  43
  44         fsp->pos = seek_ret;
  45
  46         DEBUG(10,("seek_file (%s): requested pos = %.0f, new pos = %.0f\n",
  47                 fsp->fsp_name, (double)pos, (double)fsp->pos ));
  48
  49         return(fsp->pos);
  50 }
  51
  52 /****************************************************************************
  53  Read from write cache if we can.
  54 ****************************************************************************/
  55
  56
  57 static BOOL read_from_write_cache(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
  58 {
  59         write_cache *wcp = fsp->wcp;
  60
  61         if(!wcp)
  62                 return False;
  63
  64         if(n > wcp->data_size || pos < wcp->offset || pos + n > wcp->offset + wcp->data_size)
  65                 return False;
  66
  67         memcpy(data, wcp->data + (pos - wcp->offset), n);
  68
  69         DO_PROFILE_INC(writecache_read_hits);
  70
  71         return True;
  72 }
  73
  74 /****************************************************************************
  75  Read from a file.
  76 ****************************************************************************/
  77
  78 ssize_t read_file(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
  79 {
  80         ssize_t ret=0,readret;
  81
  82         /* you can't read from print files */
  83         if (fsp->print_file)
  84                 return -1;
  85
  86         /*
  87          * Serve from write cache if we can.
  88          */
  89
  90         if(read_from_write_cache(fsp, data, pos, n))
  91                 return n;
  92
  93         flush_write_cache(fsp, READ_FLUSH);
  94
  95         if (seek_file(fsp,pos) == -1) {
  96                 DEBUG(3,("read_file: Failed to seek to %.0f\n",(double)pos));
  97                 return(ret);
  98         }
  99
 100         if (n > 0) {
 101 #ifdef DMF_FIX
 102                 int numretries = 3;
 103 tryagain:
 104                 readret = fsp->conn->vfs_ops.read(fsp,fsp->fd,data,n);
 105                 if (readret == -1) {
 106                         if ((errno == EAGAIN) && numretries) {
 107                                 DEBUG(3,("read_file EAGAIN retry in 10 seconds\n"));
 108                                 (void)sleep(10);
 109                                 --numretries;
 110                                 goto tryagain;
 111                         }
 112                         return -1;
 113                 }
 114 #else /* NO DMF fix. */
 115                 readret = fsp->conn->vfs_ops.read(fsp,fsp->fd,data,n);
 116                 if (readret == -1)
 117                         return -1;
 118 #endif
 119                 if (readret > 0)
 120                         ret += readret;
 121         }
 122
 123         DEBUG(10,("read_file (%s): pos = %.0f, size = %lu, returned %lu\n",
 124                 fsp->fsp_name, (double)pos, (unsigned long)n, (long)ret ));
 125
 126         return(ret);
 127 }
 128
 129 /* how many write cache buffers have been allocated */
 130 static unsigned int allocated_write_caches;
 131
 132 /****************************************************************************
 133  *Really* write to a file.
 134 ****************************************************************************/
 135
 136 static ssize_t real_write_file(files_struct *fsp,char *data,SMB_OFF_T pos, size_t n)
 137 {
 138         ssize_t ret;
 139
 140         if ((pos != -1) && (seek_file(fsp,pos) == -1))
 141                 return -1;
 142
 143         ret = vfs_write_data(fsp,data,n);
 144
 145         DEBUG(10,("real_write_file (%s): pos = %.0f, size = %lu, returned %ld\n",
 146                 fsp->fsp_name, (double)pos, (unsigned long)n, (long)ret ));
 147
 148         return ret;
 149 }
 150
 151 /****************************************************************************
 152 write to a file
 153 ****************************************************************************/
 154
 155 ssize_t write_file(files_struct *fsp, char *data, SMB_OFF_T pos, size_t n)
 156 {
 157         write_cache *wcp = fsp->wcp;
 158         ssize_t total_written = 0;
 159         int write_path = -1;
 160
 161         if (fsp->print_file)
 162                 return print_job_write(SNUM(fsp->conn), fsp->print_jobid, data, n);
 163
 164         if (!fsp->can_write) {
 165                 errno = EPERM;
 166                 return(0);
 167         }
 168
 169         if (!fsp->modified) {
 170                 SMB_STRUCT_STAT st;
 171                 fsp->modified = True;
 172
 173                 if (fsp->conn->vfs_ops.fstat(fsp,fsp->fd,&st) == 0) {
 174                         int dosmode = dos_mode(fsp->conn,fsp->fsp_name,&st);
 175                         fsp->size = st.st_size;
 176                         if (MAP_ARCHIVE(fsp->conn) && !IS_DOS_ARCHIVE(dosmode))
 177                                 file_chmod(fsp->conn,fsp->fsp_name,dosmode | aARCH,&st);
 178
 179                         /*
 180                          * If this is the first write and we have an exclusive oplock then setup
 181                          * the write cache.
 182                          */
 183
 184                         if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && !wcp) {
 185                                 setup_write_cache(fsp, st.st_size);
 186                                 wcp = fsp->wcp;
 187                         }
 188                 }
 189         }
 190
 191 #ifdef WITH_PROFILE
 192         DO_PROFILE_INC(writecache_total_writes);
 193         if (!fsp->oplock_type) {
 194                 DO_PROFILE_INC(writecache_non_oplock_writes);
 195         }
 196 #endif
 197
 198         /*
 199          * If this file is level II oplocked then we need
 200          * to grab the shared memory lock and inform all
 201          * other files with a level II lock that they need
 202          * to flush their read caches. We keep the lock over
 203          * the shared memory area whilst doing this.
 204          */
 205
 206         release_level_2_oplocks_on_change(fsp);
 207
 208 #ifdef WITH_PROFILE
 209         if (profile_p && profile_p->writecache_total_writes % 500 == 0) {
 210                 DEBUG(3,("WRITECACHE: initwrites=%u abutted=%u total=%u \
 211 nonop=%u allocated=%u active=%u direct=%u perfect=%u readhits=%u\n",
 212                         profile_p->writecache_init_writes,
 213                         profile_p->writecache_abutted_writes,
 214                         profile_p->writecache_total_writes,
 215                         profile_p->writecache_non_oplock_writes,
 216                         profile_p->writecache_allocated_write_caches,
 217                         profile_p->writecache_num_write_caches,
 218                         profile_p->writecache_direct_writes,
 219                         profile_p->writecache_num_perfect_writes,
 220                         profile_p->writecache_read_hits ));
 221
 222                 DEBUG(3,("WRITECACHE: Flushes SEEK=%d, READ=%d, WRITE=%d, READRAW=%d, OPLOCK=%d, CLOSE=%d, SYNC=%d\n",
 223                         profile_p->writecache_flushed_writes[SEEK_FLUSH],
 224                         profile_p->writecache_flushed_writes[READ_FLUSH],
 225                         profile_p->writecache_flushed_writes[WRITE_FLUSH],
 226                         profile_p->writecache_flushed_writes[READRAW_FLUSH],
 227                         profile_p->writecache_flushed_writes[OPLOCK_RELEASE_FLUSH],
 228                         profile_p->writecache_flushed_writes[CLOSE_FLUSH],
 229                         profile_p->writecache_flushed_writes[SYNC_FLUSH] ));
 230         }
 231 #endif
 232
 233         if(!wcp) {
 234                 DO_PROFILE_INC(writecache_direct_writes);
 235                 total_written = real_write_file(fsp, data, pos, n);
 236                 if ((total_written != -1) && (pos + total_written > fsp->size))
 237                         fsp->size = pos + total_written;
 238                 return total_written;
 239         }
 240
 241         DEBUG(9,("write_file (%s)(fd=%d pos=%.0f size=%u) wcp->offset=%.0f wcp->data_size=%u\n",
 242                 fsp->fsp_name, fsp->fd, (double)pos, (unsigned int)n, (double)wcp->offset, (unsigned int)wcp->data_size));
 243
 244         /*
 245          * If we have active cache and it isn't contiguous then we flush.
 246          * NOTE: There is a small problem with running out of disk ....
 247          */
 248
 249         if (wcp->data_size) {
 250
 251                 BOOL cache_flush_needed = False;
 252
 253                 if ((pos >= wcp->offset) && (pos <= wcp->offset + wcp->data_size)) {
 254
 255                         /* ASCII art.... JRA.
 256
 257       +--------------+-----
 258       | Cached data  | Rest of allocated cache buffer....
 259       +--------------+-----
 260
 261             +-------------------+
 262             | Data to write     |
 263             +-------------------+
 264
 265                         */
 266
 267                         /*
 268                          * Start of write overlaps or abutts the existing data.
 269                          */
 270
 271                         size_t data_used = MIN((wcp->alloc_size - (pos - wcp->offset)), n);
 272
 273                         memcpy(wcp->data + (pos - wcp->offset), data, data_used);
 274
 275                         /*
 276                          * Update the current buffer size with the new data.
 277                          */
 278
 279                         if(pos + data_used > wcp->offset + wcp->data_size)
 280                                 wcp->data_size = pos + data_used - wcp->offset;
 281
 282                         /*
 283                          * Update the file size if changed.
 284                          */
 285
 286                         if (wcp->offset + wcp->data_size > wcp->file_size)
 287                                 fsp->size = wcp->file_size = wcp->offset + wcp->data_size;
 288
 289                         /*
 290                          * If we used all the data then
 291                          * return here.
 292                          */
 293
 294                         if(n == data_used)
 295                                 return n;
 296                         else
 297                                 cache_flush_needed = True;
 298
 299                         /*
 300                          * Move the start of data forward by the amount used,
 301                          * cut down the amount left by the same amount.
 302                          */
 303
 304                         data += data_used;
 305                         pos += data_used;
 306                         n -= data_used;
 307
 308                         DO_PROFILE_INC(writecache_abutted_writes);
 309                         total_written = data_used;
 310
 311                         write_path = 1;
 312
 313                 } else if ((pos < wcp->offset) && (pos + n > wcp->offset) &&
 314                                         (pos + n <= wcp->offset + wcp->alloc_size)) {
 315
 316                         /* ASCII art.... JRA.
 317
 318                         +---------------+
 319                         | Cache buffer  |
 320                         +---------------+
 321
 322             +-------------------+
 323             | Data to write     |
 324             +-------------------+
 325
 326                         */
 327
 328                         /*
 329                          * End of write overlaps the existing data.
 330                          */
 331
 332                         size_t data_used = pos + n - wcp->offset;
 333
 334                         memcpy(wcp->data, data + n - data_used, data_used);
 335
 336                         /*
 337                          * Update the current buffer size with the new data.
 338                          */
 339
 340                         if(pos + n > wcp->offset + wcp->data_size)
 341                                 wcp->data_size = pos + n - wcp->offset;
 342
 343                         /*
 344                          * Update the file size if changed.
 345                          */
 346
 347                         if (wcp->offset + wcp->data_size > wcp->file_size)
 348                                 fsp->size = wcp->file_size = wcp->offset + wcp->data_size;
 349
 350                         /*
 351                          * We don't need to move the start of data, but we
 352                          * cut down the amount left by the amount used.
 353                          */
 354
 355                         n -= data_used;
 356
 357                         /*
 358                          * We cannot have used all the data here.
 359                          */
 360
 361                         cache_flush_needed = True;
 362
 363                         DO_PROFILE_INC(writecache_abutted_writes);
 364                         total_written = data_used;
 365
 366                         write_path = 2;
 367
 368                 } else if ( (pos >= wcp->file_size) &&
 369                                         (wcp->offset + wcp->data_size == wcp->file_size) &&
 370                                         (pos > wcp->offset + wcp->data_size) &&
 371                                         (pos < wcp->offset + wcp->alloc_size) ) {
 372
 373                         /* ASCII art.... JRA.
 374
 375                        End of file ---->|
 376
 377                         +---------------+---------------+
 378                         | Cached data   | Cache buffer  |
 379                         +---------------+---------------+
 380
 381                                               +-------------------+
 382                                               | Data to write     |
 383                                               +-------------------+
 384
 385                         */
 386
 387                         /*
 388                          * Non-contiguous write part of which fits within
 389                          * the cache buffer and is extending the file
 390                          * and the cache contents reflect the current
 391                          * data up to the current end of the file.
 392                          */
 393
 394                         size_t data_used;
 395
 396                         if(pos + n <= wcp->offset + wcp->alloc_size)
 397                                 data_used = n;
 398                         else
 399                                 data_used = wcp->offset + wcp->alloc_size - pos;
 400
 401                         /*
 402                          * Fill in the non-continuous area with zeros.
 403                          */
 404
 405                         memset(wcp->data + wcp->data_size, '\0',
 406                                 pos - (wcp->offset + wcp->data_size) );
 407
 408                         memcpy(wcp->data + (pos - wcp->offset), data, data_used);
 409
 410                         /*
 411                          * Update the current buffer size with the new data.
 412                          */
 413
 414                         if(pos + data_used > wcp->offset + wcp->data_size)
 415                                 wcp->data_size = pos + data_used - wcp->offset;
 416
 417                         /*
 418                          * Update the file size if changed.
 419                          */
 420
 421                         if (wcp->offset + wcp->data_size > wcp->file_size)
 422                                 fsp->size = wcp->file_size = wcp->offset + wcp->data_size;
 423
 424                         /*
 425                          * If we used all the data then
 426                          * return here.
 427                          */
 428
 429                         if(n == data_used)
 430                                 return n;
 431                         else
 432                                 cache_flush_needed = True;
 433
 434                         /*
 435                          * Move the start of data forward by the amount used,
 436                          * cut down the amount left by the same amount.
 437                          */
 438
 439                         data += data_used;
 440                         pos += data_used;
 441                         n -= data_used;
 442
 443                         DO_PROFILE_INC(writecache_abutted_writes);
 444                         total_written = data_used;
 445
 446                         write_path = 3;
 447
 448                 } else {
 449
 450                         /* ASCII art..... JRA.
 451
 452    Case 1).
 453
 454                         +---------------+---------------+
 455                         | Cached data   | Cache buffer  |
 456                         +---------------+---------------+
 457
 458                                                               +-------------------+
 459                                                               | Data to write     |
 460                                                               +-------------------+
 461
 462    Case 2).
 463
 464                            +---------------+---------------+
 465                            | Cached data   | Cache buffer  |
 466                            +---------------+---------------+
 467
 468    +-------------------+
 469    | Data to write     |
 470    +-------------------+
 471
 472     Case 3).
 473
 474                            +---------------+---------------+
 475                            | Cached data   | Cache buffer  |
 476                            +---------------+---------------+
 477
 478                   +-----------------------------------------------------+
 479                   | Data to write                                       |
 480                   +-----------------------------------------------------+
 481
 482                   */
 483
 484                         /*
 485                          * Write is bigger than buffer, or there is no overlap on the
 486                          * low or high ends.
 487                          */
 488
 489                         DEBUG(9,("write_file: non cacheable write : fd = %d, pos = %.0f, len = %u, current cache pos = %.0f \
 490 len = %u\n",fsp->fd, (double)pos, (unsigned int)n, (double)wcp->offset, (unsigned int)wcp->data_size ));
 491
 492                         /*
 493                          * Update the file size if needed.
 494                          */
 495
 496                         if(pos + n > wcp->file_size)
 497                                 fsp->size = wcp->file_size = pos + n;
 498
 499                         /*
 500                          * If write would fit in the cache, and is larger than
 501                          * the data already in the cache, flush the cache and
 502                          * preferentially copy the data new data into it. Otherwise
 503                          * just write the data directly.
 504                          */
 505
 506                         if ( n <= wcp->alloc_size && n > wcp->data_size) {
 507                                 cache_flush_needed = True;
 508                         } else {
 509                                 ssize_t ret = real_write_file(fsp, data, pos, n);
 510
 511                                 /*
 512                                  * If the write overlaps the entire cache, then
 513                                  * discard the current contents of the cache.
 514                                  * Fix from Rasmus Borup Hansen rbh@math.ku.dk.
 515                                  */
 516
 517                                 if ((pos <= wcp->offset) &&
 518                                                 (pos + n >= wcp->offset + wcp->data_size) ) {
 519                                         DEBUG(9,("write_file: discarding overwritten write \
 520 cache: fd = %d, off=%.0f, size=%u\n", fsp->fd, (double)wcp->offset, (unsigned int)wcp->data_size ));
 521                                         wcp->data_size = 0;
 522                                 }
 523
 524                                 DO_PROFILE_INC(writecache_direct_writes);
 525                                 if (ret == -1)
 526                                         return ret;
 527
 528                                 if (pos + ret > wcp->file_size)
 529                                         fsp->size = wcp->file_size = pos + ret;
 530
 531                                 return ret;
 532                         }
 533
 534                         write_path = 4;
 535
 536                 }
 537
 538                 if(wcp->data_size > wcp->file_size)
 539                         fsp->size = wcp->file_size = wcp->data_size;
 540
 541                 if (cache_flush_needed) {
 542                         DEBUG(3,("WRITE_FLUSH:%d: due to noncontinuous write: fd = %d, size = %.0f, pos = %.0f, \
 543 n = %u, wcp->offset=%.0f, wcp->data_size=%u\n",
 544                                 write_path, fsp->fd, (double)wcp->file_size, (double)pos, (unsigned int)n,
 545                                 (double)wcp->offset, (unsigned int)wcp->data_size ));
 546
 547                         flush_write_cache(fsp, WRITE_FLUSH);
 548                 }
 549         }
 550
 551         /*
 552          * If the write request is bigger than the cache
 553          * size, write it all out.
 554          */
 555
 556         if (n > wcp->alloc_size ) {
 557                 ssize_t ret = real_write_file(fsp, data, pos, n);
 558                 if (ret == -1)
 559                         return -1;
 560
 561                 if (pos + ret > wcp->file_size)
 562                         fsp->size = wcp->file_size = pos + n;
 563
 564                 DO_PROFILE_INC(writecache_direct_writes);
 565                 return total_written + n;
 566         }
 567
 568         /*
 569          * If there's any data left, cache it.
 570          */
 571
 572         if (n) {
 573 #ifdef WITH_PROFILE
 574                 if (wcp->data_size) {
 575                         DO_PROFILE_INC(writecache_abutted_writes);
 576                 } else {
 577                         DO_PROFILE_INC(writecache_init_writes);
 578                 }
 579 #endif
 580                 memcpy(wcp->data+wcp->data_size, data, n);
 581                 if (wcp->data_size == 0) {
 582                         wcp->offset = pos;
 583                         DO_PROFILE_INC(writecache_num_write_caches);
 584                 }
 585                 wcp->data_size += n;
 586
 587                 /*
 588                  * Update the file size if changed.
 589                  */
 590
 591                 if (wcp->offset + wcp->data_size > wcp->file_size)
 592                         fsp->size = wcp->file_size = wcp->offset + wcp->data_size;
 593                 DEBUG(9,("wcp->offset = %.0f wcp->data_size = %u cache return %u\n",
 594                         (double)wcp->offset, (unsigned int)wcp->data_size, (unsigned int)n));
 595
 596                 total_written += n;
 597                 return total_written; /* .... that's a write :) */
 598         }
 599
 600         return total_written;
 601 }
 602
 603 /****************************************************************************
 604  Delete the write cache structure.
 605 ****************************************************************************/
 606
 607 void delete_write_cache(files_struct *fsp)
 608 {
 609         write_cache *wcp;
 610
 611         if(!fsp)
 612                 return;
 613
 614         if(!(wcp = fsp->wcp))
 615                 return;
 616
 617         DO_PROFILE_DEC(writecache_allocated_write_caches);
 618         allocated_write_caches--;
 619
 620         SMB_ASSERT(wcp->data_size == 0);
 621
 622         SAFE_FREE(wcp->data);
 623         SAFE_FREE(fsp->wcp);
 624
 625         DEBUG(10,("delete_write_cache: File %s deleted write cache\n", fsp->fsp_name ));
 626 }
 627
 628 /****************************************************************************
 629  Setup the write cache structure.
 630 ****************************************************************************/
 631
 632 static BOOL setup_write_cache(files_struct *fsp, SMB_OFF_T file_size)
 633 {
 634         ssize_t alloc_size = lp_write_cache_size(SNUM(fsp->conn));
 635         write_cache *wcp;
 636
 637         if (allocated_write_caches >= MAX_WRITE_CACHES)
 638                 return False;
 639
 640         if(alloc_size == 0 || fsp->wcp)
 641                 return False;
 642
 643         if((wcp = (write_cache *)malloc(sizeof(write_cache))) == NULL) {
 644                 DEBUG(0,("setup_write_cache: malloc fail.\n"));
 645                 return False;
 646         }
 647
 648         wcp->file_size = file_size;
 649         wcp->offset = 0;
 650         wcp->alloc_size = alloc_size;
 651         wcp->data_size = 0;
 652         if((wcp->data = malloc(wcp->alloc_size)) == NULL) {
 653                 DEBUG(0,("setup_write_cache: malloc fail for buffer size %u.\n",
 654                         (unsigned int)wcp->alloc_size ));
 655                 SAFE_FREE(wcp);
 656                 return False;
 657         }
 658
 659         memset(wcp->data, '\0', wcp->alloc_size );
 660
 661         fsp->wcp = wcp;
 662         DO_PROFILE_INC(writecache_allocated_write_caches);
 663         allocated_write_caches++;
 664
 665         DEBUG(10,("setup_write_cache: File %s allocated write cache size %u\n",
 666                 fsp->fsp_name, wcp->alloc_size ));
 667
 668         return True;
 669 }
 670
 671 /****************************************************************************
 672  Cope with a size change.
 673 ****************************************************************************/
 674
 675 void set_filelen_write_cache(files_struct *fsp, SMB_OFF_T file_size)
 676 {
 677         fsp->size = file_size;
 678         if(fsp->wcp) {
 679                 /* The cache *must* have been flushed before we do this. */
 680                 if (fsp->wcp->data_size != 0) {
 681                         pstring msg;
 682                         slprintf(msg, sizeof(msg)-1, "set_filelen_write_cache: size change \
 683 on file %s with write cache size = %u\n", fsp->fsp_name, fsp->wcp->data_size );
 684                         smb_panic(msg);
 685                 }
 686                 fsp->wcp->file_size = file_size;
 687         }
 688 }
 689
 690 /*******************************************************************
 691  Flush a write cache struct to disk.
 692 ********************************************************************/
 693
 694 ssize_t flush_write_cache(files_struct *fsp, enum flush_reason_enum reason)
 695 {
 696         write_cache *wcp = fsp->wcp;
 697         size_t data_size;
 698         ssize_t ret;
 699
 700         if(!wcp || !wcp->data_size)
 701                 return 0;
 702
 703         data_size = wcp->data_size;
 704         wcp->data_size = 0;
 705
 706         DO_PROFILE_DEC_INC(writecache_num_write_caches,writecache_flushed_writes[reason]);
 707
 708         DEBUG(9,("flushing write cache: fd = %d, off=%.0f, size=%u\n",
 709                 fsp->fd, (double)wcp->offset, (unsigned int)data_size));
 710
 711 #ifdef WITH_PROFILE
 712         if(data_size == wcp->alloc_size)
 713                 DO_PROFILE_INC(writecache_num_perfect_writes);
 714 #endif
 715
 716         ret = real_write_file(fsp, wcp->data, wcp->offset, data_size);
 717
 718         /*
 719          * Ensure file size if kept up to date if write extends file.
 720          */
 721
 722         if ((ret != -1) && (wcp->offset + ret > wcp->file_size))
 723                 wcp->file_size = wcp->offset + ret;
 724
 725         return ret;
 726 }
 727
 728 /*******************************************************************
 729 sync a file
 730 ********************************************************************/
 731
 732 void sync_file(connection_struct *conn, files_struct *fsp)
 733 {
 734         if(lp_strict_sync(SNUM(conn)) && fsp->fd != -1) {
 735                 flush_write_cache(fsp, SYNC_FLUSH);
 736                 conn->vfs_ops.fsync(fsp,fsp->fd);
 737         }
 738 }
 739
 740
 741 /************************************************************
 742  Perform a stat whether a valid fd or not.
 743 ************************************************************/
 744
 745 int fsp_stat(files_struct *fsp, SMB_STRUCT_STAT *pst)
 746 {
 747         if (fsp->fd == -1)
 748                 return vfs_stat(fsp->conn, fsp->fsp_name, pst);
 749         else
 750                 return vfs_fstat(fsp,fsp->fd, pst);
 751 }