ntoskrnl/cc/view.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            ntoskrnl/cc/view.c
   5  * PURPOSE:         Cache manager
   6  *
   7  * PROGRAMMERS:     David Welch (welch@mcmail.com)
   8  *                  Pierre Schweitzer (pierre@reactos.org)
   9  */
  10
  11 /* NOTES **********************************************************************
  12  *
  13  * This is not the NT implementation of a file cache nor anything much like
  14  * it.
  15  *
  16  * The general procedure for a filesystem to implement a read or write
  17  * dispatch routine is as follows
  18  *
  19  * (1) If caching for the FCB hasn't been initiated then so do by calling
  20  * CcInitializeFileCache.
  21  *
  22  * (2) For each 4k region which is being read or written obtain a cache page
  23  * by calling CcRequestCachePage.
  24  *
  25  * (3) If either the page is being read or not completely written, and it is
  26  * not up to date then read its data from the underlying medium. If the read
  27  * fails then call CcReleaseCachePage with VALID as FALSE and return a error.
  28  *
  29  * (4) Copy the data into or out of the page as necessary.
  30  *
  31  * (5) Release the cache page
  32  */
  33 /* INCLUDES ******************************************************************/
  34
  35 #include <ntoskrnl.h>
  36 #define NDEBUG
  37 #include <debug.h>
  38
  39 #if defined (ALLOC_PRAGMA)
  40 #pragma alloc_text(INIT, CcInitView)
  41 #endif
  42
  43 /* GLOBALS *******************************************************************/
  44
  45 LIST_ENTRY DirtyVacbListHead;
  46 static LIST_ENTRY VacbLruListHead;
  47
  48 KGUARDED_MUTEX ViewLock;
  49
  50 NPAGED_LOOKASIDE_LIST iBcbLookasideList;
  51 static NPAGED_LOOKASIDE_LIST SharedCacheMapLookasideList;
  52 static NPAGED_LOOKASIDE_LIST VacbLookasideList;
  53
  54 /* Counters:
  55  * - Amount of pages flushed by lazy writer
  56  * - Number of times lazy writer ran
  57  */
  58 ULONG CcLazyWritePages = 0;
  59 ULONG CcLazyWriteIos = 0;
  60
  61 /* Internal vars (MS):
  62  * - Threshold above which lazy writer will start action
  63  * - Amount of dirty pages
  64  * - List for deferred writes
  65  * - Spinlock when dealing with the deferred list
  66  * - List for "clean" shared cache maps
  67  */
  68 ULONG CcDirtyPageThreshold = 0;
  69 ULONG CcTotalDirtyPages = 0;
  70 LIST_ENTRY CcDeferredWrites;
  71 KSPIN_LOCK CcDeferredWriteSpinLock;
  72 LIST_ENTRY CcCleanSharedCacheMapList;
  73
  74 /* Internal vars (ROS):
  75  * - Event to notify lazy writer to shutdown
  76  * - Event to inform watchers lazy writer is done for this loop
  77  * - Lock for the CcCleanSharedCacheMapList list
  78  */
  79 KEVENT iLazyWriterShutdown;
  80 KEVENT iLazyWriterNotify;
  81 KSPIN_LOCK iSharedCacheMapLock;
  82
  83 #if DBG
  84 static void CcRosVacbIncRefCount_(PROS_VACB vacb, const char* file, int line)
  85 {
  86     ++vacb->ReferenceCount;
  87     if (vacb->SharedCacheMap->Trace)
  88     {
  89         DbgPrint("(%s:%i) VACB %p ++RefCount=%lu, Dirty %u, PageOut %lu\n",
  90                  file, line, vacb, vacb->ReferenceCount, vacb->Dirty, vacb->PageOut);
  91     }
  92 }
  93 static void CcRosVacbDecRefCount_(PROS_VACB vacb, const char* file, int line)
  94 {
  95     --vacb->ReferenceCount;
  96     if (vacb->SharedCacheMap->Trace)
  97     {
  98         DbgPrint("(%s:%i) VACB %p --RefCount=%lu, Dirty %u, PageOut %lu\n",
  99                  file, line, vacb, vacb->ReferenceCount, vacb->Dirty, vacb->PageOut);
 100     }
 101 }
 102 #define CcRosVacbIncRefCount(vacb) CcRosVacbIncRefCount_(vacb,__FILE__,__LINE__)
 103 #define CcRosVacbDecRefCount(vacb) CcRosVacbDecRefCount_(vacb,__FILE__,__LINE__)
 104 #else
 105 #define CcRosVacbIncRefCount(vacb) (++((vacb)->ReferenceCount))
 106 #define CcRosVacbDecRefCount(vacb) (--((vacb)->ReferenceCount))
 107 #endif
 108
 109 NTSTATUS
 110 CcRosInternalFreeVacb(PROS_VACB Vacb);
 111
 112
 113 /* FUNCTIONS *****************************************************************/
 114
 115 VOID
 116 NTAPI
 117 CcRosTraceCacheMap (
 118     PROS_SHARED_CACHE_MAP SharedCacheMap,
 119     BOOLEAN Trace )
 120 {
 121 #if DBG
 122     KIRQL oldirql;
 123     PLIST_ENTRY current_entry;
 124     PROS_VACB current;
 125
 126     if (!SharedCacheMap)
 127         return;
 128
 129     SharedCacheMap->Trace = Trace;
 130
 131     if (Trace)
 132     {
 133         DPRINT1("Enabling Tracing for CacheMap 0x%p:\n", SharedCacheMap);
 134
 135         KeAcquireGuardedMutex(&ViewLock);
 136         KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldirql);
 137
 138         current_entry = SharedCacheMap->CacheMapVacbListHead.Flink;
 139         while (current_entry != &SharedCacheMap->CacheMapVacbListHead)
 140         {
 141             current = CONTAINING_RECORD(current_entry, ROS_VACB, CacheMapVacbListEntry);
 142             current_entry = current_entry->Flink;
 143
 144             DPRINT1("  VACB 0x%p enabled, RefCount %lu, Dirty %u, PageOut %lu\n",
 145                     current, current->ReferenceCount, current->Dirty, current->PageOut );
 146         }
 147         KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldirql);
 148         KeReleaseGuardedMutex(&ViewLock);
 149     }
 150     else
 151     {
 152         DPRINT1("Disabling Tracing for CacheMap 0x%p:\n", SharedCacheMap);
 153     }
 154
 155 #else
 156     UNREFERENCED_PARAMETER(SharedCacheMap);
 157     UNREFERENCED_PARAMETER(Trace);
 158 #endif
 159 }
 160
 161 NTSTATUS
 162 NTAPI
 163 CcRosFlushVacb (
 164     PROS_VACB Vacb)
 165 {
 166     NTSTATUS Status;
 167     KIRQL oldIrql;
 168
 169     Status = CcWriteVirtualAddress(Vacb);
 170     if (NT_SUCCESS(Status))
 171     {
 172         KeAcquireGuardedMutex(&ViewLock);
 173         KeAcquireSpinLock(&Vacb->SharedCacheMap->CacheMapLock, &oldIrql);
 174
 175         Vacb->Dirty = FALSE;
 176         RemoveEntryList(&Vacb->DirtyVacbListEntry);
 177         CcTotalDirtyPages -= VACB_MAPPING_GRANULARITY / PAGE_SIZE;
 178         CcRosVacbDecRefCount(Vacb);
 179
 180         KeReleaseSpinLock(&Vacb->SharedCacheMap->CacheMapLock, oldIrql);
 181         KeReleaseGuardedMutex(&ViewLock);
 182     }
 183
 184     return Status;
 185 }
 186
 187 NTSTATUS
 188 NTAPI
 189 CcRosFlushDirtyPages (
 190     ULONG Target,
 191     PULONG Count,
 192     BOOLEAN Wait,
 193     BOOLEAN CalledFromLazy)
 194 {
 195     PLIST_ENTRY current_entry;
 196     PROS_VACB current;
 197     BOOLEAN Locked;
 198     NTSTATUS Status;
 199     LARGE_INTEGER ZeroTimeout;
 200
 201     DPRINT("CcRosFlushDirtyPages(Target %lu)\n", Target);
 202
 203     (*Count) = 0;
 204     ZeroTimeout.QuadPart = 0;
 205
 206     KeEnterCriticalRegion();
 207     KeAcquireGuardedMutex(&ViewLock);
 208
 209     current_entry = DirtyVacbListHead.Flink;
 210     if (current_entry == &DirtyVacbListHead)
 211     {
 212         DPRINT("No Dirty pages\n");
 213     }
 214
 215     while ((current_entry != &DirtyVacbListHead) && (Target > 0))
 216     {
 217         current = CONTAINING_RECORD(current_entry,
 218                                     ROS_VACB,
 219                                     DirtyVacbListEntry);
 220         current_entry = current_entry->Flink;
 221
 222         CcRosVacbIncRefCount(current);
 223
 224         /* When performing lazy write, don't handle temporary files */
 225         if (CalledFromLazy &&
 226             BooleanFlagOn(current->SharedCacheMap->FileObject->Flags, FO_TEMPORARY_FILE))
 227         {
 228             CcRosVacbDecRefCount(current);
 229             continue;
 230         }
 231
 232         Locked = current->SharedCacheMap->Callbacks->AcquireForLazyWrite(
 233                      current->SharedCacheMap->LazyWriteContext, Wait);
 234         if (!Locked)
 235         {
 236             CcRosVacbDecRefCount(current);
 237             continue;
 238         }
 239
 240         Status = CcRosAcquireVacbLock(current,
 241                                       Wait ? NULL : &ZeroTimeout);
 242         if (Status != STATUS_SUCCESS)
 243         {
 244             current->SharedCacheMap->Callbacks->ReleaseFromLazyWrite(
 245                 current->SharedCacheMap->LazyWriteContext);
 246             CcRosVacbDecRefCount(current);
 247             continue;
 248         }
 249
 250         ASSERT(current->Dirty);
 251
 252         /* One reference is added above */
 253         if (current->ReferenceCount > 2)
 254         {
 255             CcRosReleaseVacbLock(current);
 256             current->SharedCacheMap->Callbacks->ReleaseFromLazyWrite(
 257                 current->SharedCacheMap->LazyWriteContext);
 258             CcRosVacbDecRefCount(current);
 259             continue;
 260         }
 261
 262         KeReleaseGuardedMutex(&ViewLock);
 263
 264         Status = CcRosFlushVacb(current);
 265
 266         CcRosReleaseVacbLock(current);
 267         current->SharedCacheMap->Callbacks->ReleaseFromLazyWrite(
 268             current->SharedCacheMap->LazyWriteContext);
 269
 270         KeAcquireGuardedMutex(&ViewLock);
 271         CcRosVacbDecRefCount(current);
 272
 273         if (!NT_SUCCESS(Status) && (Status != STATUS_END_OF_FILE) &&
 274             (Status != STATUS_MEDIA_WRITE_PROTECTED))
 275         {
 276             DPRINT1("CC: Failed to flush VACB.\n");
 277         }
 278         else
 279         {
 280             ULONG PagesFreed;
 281
 282             /* How many pages did we free? */
 283             PagesFreed = VACB_MAPPING_GRANULARITY / PAGE_SIZE;
 284             (*Count) += PagesFreed;
 285
 286             /* Make sure we don't overflow target! */
 287             if (Target < PagesFreed)
 288             {
 289                 /* If we would have, jump to zero directly */
 290                 Target = 0;
 291             }
 292             else
 293             {
 294                 Target -= PagesFreed;
 295             }
 296         }
 297
 298         current_entry = DirtyVacbListHead.Flink;
 299     }
 300
 301     KeReleaseGuardedMutex(&ViewLock);
 302     KeLeaveCriticalRegion();
 303
 304     DPRINT("CcRosFlushDirtyPages() finished\n");
 305     return STATUS_SUCCESS;
 306 }
 307
 308 /* FIXME: Someday this could somewhat implement write-behind/read-ahead */
 309 VOID
 310 NTAPI
 311 CciLazyWriter(PVOID Unused)
 312 {
 313     LARGE_INTEGER OneSecond;
 314
 315     OneSecond.QuadPart = (LONGLONG)-1*1000*1000*10;
 316
 317     while (TRUE)
 318     {
 319         NTSTATUS Status;
 320         PLIST_ENTRY ListEntry;
 321         ULONG Target, Count = 0;
 322
 323         /* One per second or until we have to stop */
 324         Status = KeWaitForSingleObject(&iLazyWriterShutdown,
 325                                        Executive,
 326                                        KernelMode,
 327                                        FALSE,
 328                                        &OneSecond);
 329
 330         /* If we succeeed, we've to stop running! */
 331         if (Status == STATUS_SUCCESS)
 332         {
 333             break;
 334         }
 335
 336         /* We're not sleeping anymore */
 337         KeClearEvent(&iLazyWriterNotify);
 338
 339         /* Our target is one-eighth of the dirty pages */
 340         Target = CcTotalDirtyPages / 8;
 341         if (Target != 0)
 342         {
 343             /* Flush! */
 344             DPRINT("Lazy writer starting (%d)\n", Target);
 345             CcRosFlushDirtyPages(Target, &Count, FALSE, TRUE);
 346
 347             /* And update stats */
 348             CcLazyWritePages += Count;
 349             ++CcLazyWriteIos;
 350             DPRINT("Lazy writer done (%d)\n", Count);
 351         }
 352
 353         /* Inform people waiting on us that we're done */
 354         KeSetEvent(&iLazyWriterNotify, IO_DISK_INCREMENT, FALSE);
 355
 356         /* Likely not optimal, but let's handle one deferred write now! */
 357         ListEntry = ExInterlockedRemoveHeadList(&CcDeferredWrites, &CcDeferredWriteSpinLock);
 358         if (ListEntry != NULL)
 359         {
 360             PROS_DEFERRED_WRITE_CONTEXT Context;
 361
 362             /* Extract the context */
 363             Context = CONTAINING_RECORD(ListEntry, ROS_DEFERRED_WRITE_CONTEXT, CcDeferredWritesEntry);
 364
 365             /* Can we write now? */
 366             if (CcCanIWrite(Context->FileObject, Context->BytesToWrite, FALSE, Context->Retrying))
 367             {
 368                 /* Yes! Do it, and destroy the associated context */
 369                 Context->PostRoutine(Context->Context1, Context->Context2);
 370                 ExFreePoolWithTag(Context, 'CcDw');
 371             }
 372             else
 373             {
 374                 /* Otherwise, requeue it, but in tail, so that it doesn't block others
 375                  * This is clearly to improve, but given the poor algorithm used now
 376                  * It's better than nothing!
 377                  */
 378                 ExInterlockedInsertTailList(&CcDeferredWrites,
 379                                             &Context->CcDeferredWritesEntry,
 380                                             &CcDeferredWriteSpinLock);
 381             }
 382         }
 383     }
 384 }
 385
 386 NTSTATUS
 387 CcRosTrimCache (
 388     ULONG Target,
 389     ULONG Priority,
 390     PULONG NrFreed)
 391 /*
 392  * FUNCTION: Try to free some memory from the file cache.
 393  * ARGUMENTS:
 394  *       Target - The number of pages to be freed.
 395  *       Priority - The priority of free (currently unused).
 396  *       NrFreed - Points to a variable where the number of pages
 397  *                 actually freed is returned.
 398  */
 399 {
 400     PLIST_ENTRY current_entry;
 401     PROS_VACB current;
 402     ULONG PagesFreed;
 403     KIRQL oldIrql;
 404     LIST_ENTRY FreeList;
 405     PFN_NUMBER Page;
 406     ULONG i;
 407     BOOLEAN FlushedPages = FALSE;
 408
 409     DPRINT("CcRosTrimCache(Target %lu)\n", Target);
 410
 411     InitializeListHead(&FreeList);
 412
 413     *NrFreed = 0;
 414
 415 retry:
 416     KeAcquireGuardedMutex(&ViewLock);
 417
 418     current_entry = VacbLruListHead.Flink;
 419     while (current_entry != &VacbLruListHead)
 420     {
 421         current = CONTAINING_RECORD(current_entry,
 422                                     ROS_VACB,
 423                                     VacbLruListEntry);
 424         current_entry = current_entry->Flink;
 425
 426         KeAcquireSpinLock(&current->SharedCacheMap->CacheMapLock, &oldIrql);
 427
 428         /* Reference the VACB */
 429         CcRosVacbIncRefCount(current);
 430
 431         /* Check if it's mapped and not dirty */
 432         if (current->MappedCount > 0 && !current->Dirty)
 433         {
 434             /* We have to break these locks because Cc sucks */
 435             KeReleaseSpinLock(&current->SharedCacheMap->CacheMapLock, oldIrql);
 436             KeReleaseGuardedMutex(&ViewLock);
 437
 438             /* Page out the VACB */
 439             for (i = 0; i < VACB_MAPPING_GRANULARITY / PAGE_SIZE; i++)
 440             {
 441                 Page = (PFN_NUMBER)(MmGetPhysicalAddress((PUCHAR)current->BaseAddress + (i * PAGE_SIZE)).QuadPart >> PAGE_SHIFT);
 442
 443                 MmPageOutPhysicalAddress(Page);
 444             }
 445
 446             /* Reacquire the locks */
 447             KeAcquireGuardedMutex(&ViewLock);
 448             KeAcquireSpinLock(&current->SharedCacheMap->CacheMapLock, &oldIrql);
 449         }
 450
 451         /* Dereference the VACB */
 452         CcRosVacbDecRefCount(current);
 453
 454         /* Check if we can free this entry now */
 455         if (current->ReferenceCount == 0)
 456         {
 457             ASSERT(!current->Dirty);
 458             ASSERT(!current->MappedCount);
 459
 460             RemoveEntryList(&current->CacheMapVacbListEntry);
 461             RemoveEntryList(&current->VacbLruListEntry);
 462             InsertHeadList(&FreeList, &current->CacheMapVacbListEntry);
 463
 464             /* Calculate how many pages we freed for Mm */
 465             PagesFreed = min(VACB_MAPPING_GRANULARITY / PAGE_SIZE, Target);
 466             Target -= PagesFreed;
 467             (*NrFreed) += PagesFreed;
 468         }
 469
 470         KeReleaseSpinLock(&current->SharedCacheMap->CacheMapLock, oldIrql);
 471     }
 472
 473     KeReleaseGuardedMutex(&ViewLock);
 474
 475     /* Try flushing pages if we haven't met our target */
 476     if ((Target > 0) && !FlushedPages)
 477     {
 478         /* Flush dirty pages to disk */
 479         CcRosFlushDirtyPages(Target, &PagesFreed, FALSE, FALSE);
 480         FlushedPages = TRUE;
 481
 482         /* We can only swap as many pages as we flushed */
 483         if (PagesFreed < Target) Target = PagesFreed;
 484
 485         /* Check if we flushed anything */
 486         if (PagesFreed != 0)
 487         {
 488             /* Try again after flushing dirty pages */
 489             DPRINT("Flushed %lu dirty cache pages to disk\n", PagesFreed);
 490             goto retry;
 491         }
 492     }
 493
 494     while (!IsListEmpty(&FreeList))
 495     {
 496         current_entry = RemoveHeadList(&FreeList);
 497         current = CONTAINING_RECORD(current_entry,
 498                                     ROS_VACB,
 499                                     CacheMapVacbListEntry);
 500         CcRosInternalFreeVacb(current);
 501     }
 502
 503     DPRINT("Evicted %lu cache pages\n", (*NrFreed));
 504
 505     return STATUS_SUCCESS;
 506 }
 507
 508 NTSTATUS
 509 NTAPI
 510 CcRosReleaseVacb (
 511     PROS_SHARED_CACHE_MAP SharedCacheMap,
 512     PROS_VACB Vacb,
 513     BOOLEAN Valid,
 514     BOOLEAN Dirty,
 515     BOOLEAN Mapped)
 516 {
 517     BOOLEAN WasDirty;
 518     KIRQL oldIrql;
 519
 520     ASSERT(SharedCacheMap);
 521
 522     DPRINT("CcRosReleaseVacb(SharedCacheMap 0x%p, Vacb 0x%p, Valid %u)\n",
 523            SharedCacheMap, Vacb, Valid);
 524
 525     KeAcquireGuardedMutex(&ViewLock);
 526     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 527
 528     Vacb->Valid = Valid;
 529
 530     WasDirty = Vacb->Dirty;
 531     Vacb->Dirty = Vacb->Dirty || Dirty;
 532
 533     if (!WasDirty && Vacb->Dirty)
 534     {
 535         InsertTailList(&DirtyVacbListHead, &Vacb->DirtyVacbListEntry);
 536         CcTotalDirtyPages += VACB_MAPPING_GRANULARITY / PAGE_SIZE;
 537     }
 538
 539     if (Mapped)
 540     {
 541         Vacb->MappedCount++;
 542     }
 543     CcRosVacbDecRefCount(Vacb);
 544     if (Mapped && (Vacb->MappedCount == 1))
 545     {
 546         CcRosVacbIncRefCount(Vacb);
 547     }
 548     if (!WasDirty && Vacb->Dirty)
 549     {
 550         CcRosVacbIncRefCount(Vacb);
 551     }
 552
 553     KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 554     KeReleaseGuardedMutex(&ViewLock);
 555     CcRosReleaseVacbLock(Vacb);
 556
 557     return STATUS_SUCCESS;
 558 }
 559
 560 /* Returns with VACB Lock Held! */
 561 PROS_VACB
 562 NTAPI
 563 CcRosLookupVacb (
 564     PROS_SHARED_CACHE_MAP SharedCacheMap,
 565     LONGLONG FileOffset)
 566 {
 567     PLIST_ENTRY current_entry;
 568     PROS_VACB current;
 569     KIRQL oldIrql;
 570
 571     ASSERT(SharedCacheMap);
 572
 573     DPRINT("CcRosLookupVacb(SharedCacheMap 0x%p, FileOffset %I64u)\n",
 574            SharedCacheMap, FileOffset);
 575
 576     KeAcquireGuardedMutex(&ViewLock);
 577     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 578
 579     current_entry = SharedCacheMap->CacheMapVacbListHead.Flink;
 580     while (current_entry != &SharedCacheMap->CacheMapVacbListHead)
 581     {
 582         current = CONTAINING_RECORD(current_entry,
 583                                     ROS_VACB,
 584                                     CacheMapVacbListEntry);
 585         if (IsPointInRange(current->FileOffset.QuadPart,
 586                            VACB_MAPPING_GRANULARITY,
 587                            FileOffset))
 588         {
 589             CcRosVacbIncRefCount(current);
 590             KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 591             KeReleaseGuardedMutex(&ViewLock);
 592             CcRosAcquireVacbLock(current, NULL);
 593             return current;
 594         }
 595         if (current->FileOffset.QuadPart > FileOffset)
 596             break;
 597         current_entry = current_entry->Flink;
 598     }
 599
 600     KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 601     KeReleaseGuardedMutex(&ViewLock);
 602
 603     return NULL;
 604 }
 605
 606 VOID
 607 NTAPI
 608 CcRosMarkDirtyVacb (
 609     PROS_VACB Vacb)
 610 {
 611     KIRQL oldIrql;
 612     PROS_SHARED_CACHE_MAP SharedCacheMap;
 613
 614     SharedCacheMap = Vacb->SharedCacheMap;
 615
 616     KeAcquireGuardedMutex(&ViewLock);
 617     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 618
 619     if (!Vacb->Dirty)
 620     {
 621         InsertTailList(&DirtyVacbListHead, &Vacb->DirtyVacbListEntry);
 622         CcTotalDirtyPages += VACB_MAPPING_GRANULARITY / PAGE_SIZE;
 623     }
 624     else
 625     {
 626         CcRosVacbDecRefCount(Vacb);
 627     }
 628
 629     /* Move to the tail of the LRU list */
 630     RemoveEntryList(&Vacb->VacbLruListEntry);
 631     InsertTailList(&VacbLruListHead, &Vacb->VacbLruListEntry);
 632
 633     Vacb->Dirty = TRUE;
 634
 635     KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 636     KeReleaseGuardedMutex(&ViewLock);
 637 }
 638
 639 NTSTATUS
 640 NTAPI
 641 CcRosMarkDirtyFile (
 642     PROS_SHARED_CACHE_MAP SharedCacheMap,
 643     LONGLONG FileOffset)
 644 {
 645     PROS_VACB Vacb;
 646
 647     ASSERT(SharedCacheMap);
 648
 649     DPRINT("CcRosMarkDirtyVacb(SharedCacheMap 0x%p, FileOffset %I64u)\n",
 650            SharedCacheMap, FileOffset);
 651
 652     Vacb = CcRosLookupVacb(SharedCacheMap, FileOffset);
 653     if (Vacb == NULL)
 654     {
 655         KeBugCheck(CACHE_MANAGER);
 656     }
 657
 658     CcRosMarkDirtyVacb(Vacb);
 659
 660
 661     CcRosReleaseVacbLock(Vacb);
 662
 663     return STATUS_SUCCESS;
 664 }
 665
 666 NTSTATUS
 667 NTAPI
 668 CcRosUnmapVacb (
 669     PROS_SHARED_CACHE_MAP SharedCacheMap,
 670     LONGLONG FileOffset,
 671     BOOLEAN NowDirty)
 672 {
 673     PROS_VACB Vacb;
 674     BOOLEAN WasDirty;
 675     KIRQL oldIrql;
 676
 677     ASSERT(SharedCacheMap);
 678
 679     DPRINT("CcRosUnmapVacb(SharedCacheMap 0x%p, FileOffset %I64u, NowDirty %u)\n",
 680            SharedCacheMap, FileOffset, NowDirty);
 681
 682     Vacb = CcRosLookupVacb(SharedCacheMap, FileOffset);
 683     if (Vacb == NULL)
 684     {
 685         return STATUS_UNSUCCESSFUL;
 686     }
 687
 688     KeAcquireGuardedMutex(&ViewLock);
 689     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 690
 691     WasDirty = Vacb->Dirty;
 692     Vacb->Dirty = Vacb->Dirty || NowDirty;
 693
 694     Vacb->MappedCount--;
 695
 696     if (!WasDirty && NowDirty)
 697     {
 698         InsertTailList(&DirtyVacbListHead, &Vacb->DirtyVacbListEntry);
 699         CcTotalDirtyPages += VACB_MAPPING_GRANULARITY / PAGE_SIZE;
 700     }
 701
 702     CcRosVacbDecRefCount(Vacb);
 703     if (!WasDirty && NowDirty)
 704     {
 705         CcRosVacbIncRefCount(Vacb);
 706     }
 707     if (Vacb->MappedCount == 0)
 708     {
 709         CcRosVacbDecRefCount(Vacb);
 710     }
 711
 712     KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 713     KeReleaseGuardedMutex(&ViewLock);
 714     CcRosReleaseVacbLock(Vacb);
 715
 716     return STATUS_SUCCESS;
 717 }
 718
 719 static
 720 NTSTATUS
 721 CcRosMapVacb(
 722     PROS_VACB Vacb)
 723 {
 724     ULONG i;
 725     NTSTATUS Status;
 726     ULONG_PTR NumberOfPages;
 727
 728     /* Create a memory area. */
 729     MmLockAddressSpace(MmGetKernelAddressSpace());
 730     Status = MmCreateMemoryArea(MmGetKernelAddressSpace(),
 731                                 0, // nothing checks for VACB mareas, so set to 0
 732                                 &Vacb->BaseAddress,
 733                                 VACB_MAPPING_GRANULARITY,
 734                                 PAGE_READWRITE,
 735                                 (PMEMORY_AREA*)&Vacb->MemoryArea,
 736                                 0,
 737                                 PAGE_SIZE);
 738     MmUnlockAddressSpace(MmGetKernelAddressSpace());
 739     if (!NT_SUCCESS(Status))
 740     {
 741         DPRINT1("MmCreateMemoryArea failed with %lx for VACB %p\n", Status, Vacb);
 742         return Status;
 743     }
 744
 745     ASSERT(((ULONG_PTR)Vacb->BaseAddress % PAGE_SIZE) == 0);
 746     ASSERT((ULONG_PTR)Vacb->BaseAddress > (ULONG_PTR)MmSystemRangeStart);
 747
 748     /* Create a virtual mapping for this memory area */
 749     NumberOfPages = BYTES_TO_PAGES(VACB_MAPPING_GRANULARITY);
 750     for (i = 0; i < NumberOfPages; i++)
 751     {
 752         PFN_NUMBER PageFrameNumber;
 753
 754         MI_SET_USAGE(MI_USAGE_CACHE);
 755         Status = MmRequestPageMemoryConsumer(MC_CACHE, TRUE, &PageFrameNumber);
 756         if (PageFrameNumber == 0)
 757         {
 758             DPRINT1("Unable to allocate page\n");
 759             KeBugCheck(MEMORY_MANAGEMENT);
 760         }
 761
 762         Status = MmCreateVirtualMapping(NULL,
 763                                         (PVOID)((ULONG_PTR)Vacb->BaseAddress + (i * PAGE_SIZE)),
 764                                         PAGE_READWRITE,
 765                                         &PageFrameNumber,
 766                                         1);
 767         if (!NT_SUCCESS(Status))
 768         {
 769             DPRINT1("Unable to create virtual mapping\n");
 770             KeBugCheck(MEMORY_MANAGEMENT);
 771         }
 772     }
 773
 774     return STATUS_SUCCESS;
 775 }
 776
 777 static
 778 NTSTATUS
 779 CcRosCreateVacb (
 780     PROS_SHARED_CACHE_MAP SharedCacheMap,
 781     LONGLONG FileOffset,
 782     PROS_VACB *Vacb)
 783 {
 784     PROS_VACB current;
 785     PROS_VACB previous;
 786     PLIST_ENTRY current_entry;
 787     NTSTATUS Status;
 788     KIRQL oldIrql;
 789
 790     ASSERT(SharedCacheMap);
 791
 792     DPRINT("CcRosCreateVacb()\n");
 793
 794     if (FileOffset >= SharedCacheMap->SectionSize.QuadPart)
 795     {
 796         *Vacb = NULL;
 797         return STATUS_INVALID_PARAMETER;
 798     }
 799
 800     current = ExAllocateFromNPagedLookasideList(&VacbLookasideList);
 801     current->BaseAddress = NULL;
 802     current->Valid = FALSE;
 803     current->Dirty = FALSE;
 804     current->PageOut = FALSE;
 805     current->FileOffset.QuadPart = ROUND_DOWN(FileOffset, VACB_MAPPING_GRANULARITY);
 806     current->SharedCacheMap = SharedCacheMap;
 807 #if DBG
 808     if (SharedCacheMap->Trace)
 809     {
 810         DPRINT1("CacheMap 0x%p: new VACB: 0x%p\n", SharedCacheMap, current);
 811     }
 812 #endif
 813     current->MappedCount = 0;
 814     current->DirtyVacbListEntry.Flink = NULL;
 815     current->DirtyVacbListEntry.Blink = NULL;
 816     current->ReferenceCount = 1;
 817     current->PinCount = 0;
 818     KeInitializeMutex(&current->Mutex, 0);
 819     CcRosAcquireVacbLock(current, NULL);
 820     KeAcquireGuardedMutex(&ViewLock);
 821
 822     *Vacb = current;
 823     /* There is window between the call to CcRosLookupVacb
 824      * and CcRosCreateVacb. We must check if a VACB for the
 825      * file offset exist. If there is a VACB, we release
 826      * our newly created VACB and return the existing one.
 827      */
 828     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 829     current_entry = SharedCacheMap->CacheMapVacbListHead.Flink;
 830     previous = NULL;
 831     while (current_entry != &SharedCacheMap->CacheMapVacbListHead)
 832     {
 833         current = CONTAINING_RECORD(current_entry,
 834                                     ROS_VACB,
 835                                     CacheMapVacbListEntry);
 836         if (IsPointInRange(current->FileOffset.QuadPart,
 837                            VACB_MAPPING_GRANULARITY,
 838                            FileOffset))
 839         {
 840             CcRosVacbIncRefCount(current);
 841             KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 842 #if DBG
 843             if (SharedCacheMap->Trace)
 844             {
 845                 DPRINT1("CacheMap 0x%p: deleting newly created VACB 0x%p ( found existing one 0x%p )\n",
 846                         SharedCacheMap,
 847                         (*Vacb),
 848                         current);
 849             }
 850 #endif
 851             CcRosReleaseVacbLock(*Vacb);
 852             KeReleaseGuardedMutex(&ViewLock);
 853             ExFreeToNPagedLookasideList(&VacbLookasideList, *Vacb);
 854             *Vacb = current;
 855             CcRosAcquireVacbLock(current, NULL);
 856             return STATUS_SUCCESS;
 857         }
 858         if (current->FileOffset.QuadPart < FileOffset)
 859         {
 860             ASSERT(previous == NULL ||
 861                    previous->FileOffset.QuadPart < current->FileOffset.QuadPart);
 862             previous = current;
 863         }
 864         if (current->FileOffset.QuadPart > FileOffset)
 865             break;
 866         current_entry = current_entry->Flink;
 867     }
 868     /* There was no existing VACB. */
 869     current = *Vacb;
 870     if (previous)
 871     {
 872         InsertHeadList(&previous->CacheMapVacbListEntry, &current->CacheMapVacbListEntry);
 873     }
 874     else
 875     {
 876         InsertHeadList(&SharedCacheMap->CacheMapVacbListHead, &current->CacheMapVacbListEntry);
 877     }
 878     KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
 879     InsertTailList(&VacbLruListHead, &current->VacbLruListEntry);
 880     KeReleaseGuardedMutex(&ViewLock);
 881
 882     MI_SET_USAGE(MI_USAGE_CACHE);
 883 #if MI_TRACE_PFNS
 884     if ((SharedCacheMap->FileObject) && (SharedCacheMap->FileObject->FileName.Buffer))
 885     {
 886         PWCHAR pos = NULL;
 887         ULONG len = 0;
 888         pos = wcsrchr(SharedCacheMap->FileObject->FileName.Buffer, '\\');
 889         if (pos)
 890         {
 891             len = wcslen(pos) * sizeof(WCHAR);
 892             snprintf(MI_PFN_CURRENT_PROCESS_NAME, min(16, len), "%S", pos);
 893         }
 894         else
 895         {
 896             snprintf(MI_PFN_CURRENT_PROCESS_NAME, min(16, len), "%wZ", &SharedCacheMap->FileObject->FileName);
 897         }
 898     }
 899 #endif
 900
 901     Status = CcRosMapVacb(current);
 902     if (!NT_SUCCESS(Status))
 903     {
 904         RemoveEntryList(&current->CacheMapVacbListEntry);
 905         RemoveEntryList(&current->VacbLruListEntry);
 906         CcRosReleaseVacbLock(current);
 907         ExFreeToNPagedLookasideList(&VacbLookasideList, current);
 908     }
 909
 910     return Status;
 911 }
 912
 913 NTSTATUS
 914 NTAPI
 915 CcRosGetVacb (
 916     PROS_SHARED_CACHE_MAP SharedCacheMap,
 917     LONGLONG FileOffset,
 918     PLONGLONG BaseOffset,
 919     PVOID* BaseAddress,
 920     PBOOLEAN UptoDate,
 921     PROS_VACB *Vacb)
 922 {
 923     PROS_VACB current;
 924     NTSTATUS Status;
 925
 926     ASSERT(SharedCacheMap);
 927
 928     DPRINT("CcRosGetVacb()\n");
 929
 930     /*
 931      * Look for a VACB already mapping the same data.
 932      */
 933     current = CcRosLookupVacb(SharedCacheMap, FileOffset);
 934     if (current == NULL)
 935     {
 936         /*
 937          * Otherwise create a new VACB.
 938          */
 939         Status = CcRosCreateVacb(SharedCacheMap, FileOffset, &current);
 940         if (!NT_SUCCESS(Status))
 941         {
 942             return Status;
 943         }
 944     }
 945
 946     KeAcquireGuardedMutex(&ViewLock);
 947
 948     /* Move to the tail of the LRU list */
 949     RemoveEntryList(&current->VacbLruListEntry);
 950     InsertTailList(&VacbLruListHead, &current->VacbLruListEntry);
 951
 952     KeReleaseGuardedMutex(&ViewLock);
 953
 954     /*
 955      * Return information about the VACB to the caller.
 956      */
 957     *UptoDate = current->Valid;
 958     *BaseAddress = current->BaseAddress;
 959     DPRINT("*BaseAddress %p\n", *BaseAddress);
 960     *Vacb = current;
 961     *BaseOffset = current->FileOffset.QuadPart;
 962     return STATUS_SUCCESS;
 963 }
 964
 965 NTSTATUS
 966 NTAPI
 967 CcRosRequestVacb (
 968     PROS_SHARED_CACHE_MAP SharedCacheMap,
 969     LONGLONG FileOffset,
 970     PVOID* BaseAddress,
 971     PBOOLEAN UptoDate,
 972     PROS_VACB *Vacb)
 973 /*
 974  * FUNCTION: Request a page mapping for a shared cache map
 975  */
 976 {
 977     LONGLONG BaseOffset;
 978
 979     ASSERT(SharedCacheMap);
 980
 981     if (FileOffset % VACB_MAPPING_GRANULARITY != 0)
 982     {
 983         DPRINT1("Bad fileoffset %I64x should be multiple of %x",
 984                 FileOffset, VACB_MAPPING_GRANULARITY);
 985         KeBugCheck(CACHE_MANAGER);
 986     }
 987
 988     return CcRosGetVacb(SharedCacheMap,
 989                         FileOffset,
 990                         &BaseOffset,
 991                         BaseAddress,
 992                         UptoDate,
 993                         Vacb);
 994 }
 995
 996 static
 997 VOID
 998 CcFreeCachePage (
 999     PVOID Context,
1000     MEMORY_AREA* MemoryArea,
1001     PVOID Address,
1002     PFN_NUMBER Page,
1003     SWAPENTRY SwapEntry,
1004     BOOLEAN Dirty)
1005 {
1006     ASSERT(SwapEntry == 0);
1007     if (Page != 0)
1008     {
1009         ASSERT(MmGetReferenceCountPage(Page) == 1);
1010         MmReleasePageMemoryConsumer(MC_CACHE, Page);
1011     }
1012 }
1013
1014 NTSTATUS
1015 CcRosInternalFreeVacb (
1016     PROS_VACB Vacb)
1017 /*
1018  * FUNCTION: Releases a VACB associated with a shared cache map
1019  */
1020 {
1021     DPRINT("Freeing VACB 0x%p\n", Vacb);
1022 #if DBG
1023     if (Vacb->SharedCacheMap->Trace)
1024     {
1025         DPRINT1("CacheMap 0x%p: deleting VACB: 0x%p\n", Vacb->SharedCacheMap, Vacb);
1026     }
1027 #endif
1028
1029     MmLockAddressSpace(MmGetKernelAddressSpace());
1030     MmFreeMemoryArea(MmGetKernelAddressSpace(),
1031                      Vacb->MemoryArea,
1032                      CcFreeCachePage,
1033                      NULL);
1034     MmUnlockAddressSpace(MmGetKernelAddressSpace());
1035
1036     ExFreeToNPagedLookasideList(&VacbLookasideList, Vacb);
1037     return STATUS_SUCCESS;
1038 }
1039
1040 /*
1041  * @implemented
1042  */
1043 VOID
1044 NTAPI
1045 CcFlushCache (
1046     IN PSECTION_OBJECT_POINTERS SectionObjectPointers,
1047     IN PLARGE_INTEGER FileOffset OPTIONAL,
1048     IN ULONG Length,
1049     OUT PIO_STATUS_BLOCK IoStatus)
1050 {
1051     PROS_SHARED_CACHE_MAP SharedCacheMap;
1052     LARGE_INTEGER Offset;
1053     LONGLONG RemainingLength;
1054     PROS_VACB current;
1055     NTSTATUS Status;
1056     KIRQL oldIrql;
1057
1058     CCTRACE(CC_API_DEBUG, "SectionObjectPointers=%p FileOffset=%p Length=%lu\n",
1059         SectionObjectPointers, FileOffset, Length);
1060
1061     DPRINT("CcFlushCache(SectionObjectPointers 0x%p, FileOffset 0x%p, Length %lu, IoStatus 0x%p)\n",
1062            SectionObjectPointers, FileOffset, Length, IoStatus);
1063
1064     if (SectionObjectPointers && SectionObjectPointers->SharedCacheMap)
1065     {
1066         SharedCacheMap = SectionObjectPointers->SharedCacheMap;
1067         ASSERT(SharedCacheMap);
1068         if (FileOffset)
1069         {
1070             Offset = *FileOffset;
1071             RemainingLength = Length;
1072         }
1073         else
1074         {
1075             Offset.QuadPart = 0;
1076             RemainingLength = SharedCacheMap->FileSize.QuadPart;
1077         }
1078
1079         if (IoStatus)
1080         {
1081             IoStatus->Status = STATUS_SUCCESS;
1082             IoStatus->Information = 0;
1083         }
1084
1085         while (RemainingLength > 0)
1086         {
1087             current = CcRosLookupVacb(SharedCacheMap, Offset.QuadPart);
1088             if (current != NULL)
1089             {
1090                 if (current->Dirty)
1091                 {
1092                     Status = CcRosFlushVacb(current);
1093                     if (!NT_SUCCESS(Status) && IoStatus != NULL)
1094                     {
1095                         IoStatus->Status = Status;
1096                     }
1097                 }
1098
1099                 CcRosReleaseVacbLock(current);
1100
1101                 KeAcquireGuardedMutex(&ViewLock);
1102                 KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
1103                 CcRosVacbDecRefCount(current);
1104                 KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
1105                 KeReleaseGuardedMutex(&ViewLock);
1106             }
1107
1108             Offset.QuadPart += VACB_MAPPING_GRANULARITY;
1109             RemainingLength -= min(RemainingLength, VACB_MAPPING_GRANULARITY);
1110         }
1111     }
1112     else
1113     {
1114         if (IoStatus)
1115         {
1116             IoStatus->Status = STATUS_INVALID_PARAMETER;
1117         }
1118     }
1119 }
1120
1121 NTSTATUS
1122 NTAPI
1123 CcRosDeleteFileCache (
1124     PFILE_OBJECT FileObject,
1125     PROS_SHARED_CACHE_MAP SharedCacheMap)
1126 /*
1127  * FUNCTION: Releases the shared cache map associated with a file object
1128  */
1129 {
1130     PLIST_ENTRY current_entry;
1131     PROS_VACB current;
1132     LIST_ENTRY FreeList;
1133     KIRQL oldIrql;
1134
1135     ASSERT(SharedCacheMap);
1136
1137     SharedCacheMap->OpenCount++;
1138     KeReleaseGuardedMutex(&ViewLock);
1139
1140     CcFlushCache(FileObject->SectionObjectPointer, NULL, 0, NULL);
1141
1142     KeAcquireGuardedMutex(&ViewLock);
1143     SharedCacheMap->OpenCount--;
1144     if (SharedCacheMap->OpenCount == 0)
1145     {
1146         KIRQL OldIrql;
1147
1148         FileObject->SectionObjectPointer->SharedCacheMap = NULL;
1149
1150         /*
1151          * Release all VACBs
1152          */
1153         InitializeListHead(&FreeList);
1154         KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
1155         while (!IsListEmpty(&SharedCacheMap->CacheMapVacbListHead))
1156         {
1157             current_entry = RemoveTailList(&SharedCacheMap->CacheMapVacbListHead);
1158             current = CONTAINING_RECORD(current_entry, ROS_VACB, CacheMapVacbListEntry);
1159             RemoveEntryList(&current->VacbLruListEntry);
1160             if (current->Dirty)
1161             {
1162                 RemoveEntryList(&current->DirtyVacbListEntry);
1163                 CcTotalDirtyPages -= VACB_MAPPING_GRANULARITY / PAGE_SIZE;
1164                 DPRINT1("Freeing dirty VACB\n");
1165             }
1166             InsertHeadList(&FreeList, &current->CacheMapVacbListEntry);
1167         }
1168 #if DBG
1169         SharedCacheMap->Trace = FALSE;
1170 #endif
1171         KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, oldIrql);
1172
1173         KeReleaseGuardedMutex(&ViewLock);
1174         ObDereferenceObject(SharedCacheMap->FileObject);
1175
1176         while (!IsListEmpty(&FreeList))
1177         {
1178             current_entry = RemoveTailList(&FreeList);
1179             current = CONTAINING_RECORD(current_entry, ROS_VACB, CacheMapVacbListEntry);
1180             CcRosInternalFreeVacb(current);
1181         }
1182
1183         KeAcquireSpinLock(&iSharedCacheMapLock, &OldIrql);
1184         RemoveEntryList(&SharedCacheMap->SharedCacheMapLinks);
1185         KeReleaseSpinLock(&iSharedCacheMapLock, OldIrql);
1186
1187         ExFreeToNPagedLookasideList(&SharedCacheMapLookasideList, SharedCacheMap);
1188         KeAcquireGuardedMutex(&ViewLock);
1189     }
1190     return STATUS_SUCCESS;
1191 }
1192
1193 VOID
1194 NTAPI
1195 CcRosReferenceCache (
1196     PFILE_OBJECT FileObject)
1197 {
1198     PROS_SHARED_CACHE_MAP SharedCacheMap;
1199     KeAcquireGuardedMutex(&ViewLock);
1200     SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
1201     ASSERT(SharedCacheMap);
1202     ASSERT(SharedCacheMap->OpenCount != 0);
1203     SharedCacheMap->OpenCount++;
1204     KeReleaseGuardedMutex(&ViewLock);
1205 }
1206
1207 VOID
1208 NTAPI
1209 CcRosRemoveIfClosed (
1210     PSECTION_OBJECT_POINTERS SectionObjectPointer)
1211 {
1212     PROS_SHARED_CACHE_MAP SharedCacheMap;
1213     DPRINT("CcRosRemoveIfClosed()\n");
1214     KeAcquireGuardedMutex(&ViewLock);
1215     SharedCacheMap = SectionObjectPointer->SharedCacheMap;
1216     if (SharedCacheMap && SharedCacheMap->OpenCount == 0)
1217     {
1218         CcRosDeleteFileCache(SharedCacheMap->FileObject, SharedCacheMap);
1219     }
1220     KeReleaseGuardedMutex(&ViewLock);
1221 }
1222
1223
1224 VOID
1225 NTAPI
1226 CcRosDereferenceCache (
1227     PFILE_OBJECT FileObject)
1228 {
1229     PROS_SHARED_CACHE_MAP SharedCacheMap;
1230     KeAcquireGuardedMutex(&ViewLock);
1231     SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
1232     ASSERT(SharedCacheMap);
1233     if (SharedCacheMap->OpenCount > 0)
1234     {
1235         SharedCacheMap->OpenCount--;
1236         if (SharedCacheMap->OpenCount == 0)
1237         {
1238             MmFreeSectionSegments(SharedCacheMap->FileObject);
1239             CcRosDeleteFileCache(FileObject, SharedCacheMap);
1240         }
1241     }
1242     KeReleaseGuardedMutex(&ViewLock);
1243 }
1244
1245 NTSTATUS
1246 NTAPI
1247 CcRosReleaseFileCache (
1248     PFILE_OBJECT FileObject)
1249 /*
1250  * FUNCTION: Called by the file system when a handle to a file object
1251  * has been closed.
1252  */
1253 {
1254     PROS_SHARED_CACHE_MAP SharedCacheMap;
1255
1256     KeAcquireGuardedMutex(&ViewLock);
1257
1258     if (FileObject->SectionObjectPointer->SharedCacheMap != NULL)
1259     {
1260         SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
1261         if (FileObject->PrivateCacheMap != NULL)
1262         {
1263             FileObject->PrivateCacheMap = NULL;
1264             if (SharedCacheMap->OpenCount > 0)
1265             {
1266                 SharedCacheMap->OpenCount--;
1267                 if (SharedCacheMap->OpenCount == 0)
1268                 {
1269                     MmFreeSectionSegments(SharedCacheMap->FileObject);
1270                     CcRosDeleteFileCache(FileObject, SharedCacheMap);
1271                 }
1272             }
1273         }
1274     }
1275     KeReleaseGuardedMutex(&ViewLock);
1276     return STATUS_SUCCESS;
1277 }
1278
1279 NTSTATUS
1280 NTAPI
1281 CcTryToInitializeFileCache (
1282     PFILE_OBJECT FileObject)
1283 {
1284     PROS_SHARED_CACHE_MAP SharedCacheMap;
1285     NTSTATUS Status;
1286
1287     KeAcquireGuardedMutex(&ViewLock);
1288
1289     ASSERT(FileObject->SectionObjectPointer);
1290     SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
1291     if (SharedCacheMap == NULL)
1292     {
1293         Status = STATUS_UNSUCCESSFUL;
1294     }
1295     else
1296     {
1297         if (FileObject->PrivateCacheMap == NULL)
1298         {
1299             FileObject->PrivateCacheMap = SharedCacheMap;
1300             SharedCacheMap->OpenCount++;
1301         }
1302         Status = STATUS_SUCCESS;
1303     }
1304     KeReleaseGuardedMutex(&ViewLock);
1305
1306     return Status;
1307 }
1308
1309
1310 NTSTATUS
1311 NTAPI
1312 CcRosInitializeFileCache (
1313     PFILE_OBJECT FileObject,
1314     PCC_FILE_SIZES FileSizes,
1315     BOOLEAN PinAccess,
1316     PCACHE_MANAGER_CALLBACKS CallBacks,
1317     PVOID LazyWriterContext)
1318 /*
1319  * FUNCTION: Initializes a shared cache map for a file object
1320  */
1321 {
1322     PROS_SHARED_CACHE_MAP SharedCacheMap;
1323
1324     SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
1325     DPRINT("CcRosInitializeFileCache(FileObject 0x%p, SharedCacheMap 0x%p)\n",
1326            FileObject, SharedCacheMap);
1327
1328     KeAcquireGuardedMutex(&ViewLock);
1329     if (SharedCacheMap == NULL)
1330     {
1331         KIRQL OldIrql;
1332
1333         SharedCacheMap = ExAllocateFromNPagedLookasideList(&SharedCacheMapLookasideList);
1334         if (SharedCacheMap == NULL)
1335         {
1336             KeReleaseGuardedMutex(&ViewLock);
1337             return STATUS_INSUFFICIENT_RESOURCES;
1338         }
1339         RtlZeroMemory(SharedCacheMap, sizeof(*SharedCacheMap));
1340         ObReferenceObjectByPointer(FileObject,
1341                                    FILE_ALL_ACCESS,
1342                                    NULL,
1343                                    KernelMode);
1344         SharedCacheMap->FileObject = FileObject;
1345         SharedCacheMap->Callbacks = CallBacks;
1346         SharedCacheMap->LazyWriteContext = LazyWriterContext;
1347         SharedCacheMap->SectionSize = FileSizes->AllocationSize;
1348         SharedCacheMap->FileSize = FileSizes->FileSize;
1349         SharedCacheMap->PinAccess = PinAccess;
1350         SharedCacheMap->DirtyPageThreshold = 0;
1351         KeInitializeSpinLock(&SharedCacheMap->CacheMapLock);
1352         InitializeListHead(&SharedCacheMap->CacheMapVacbListHead);
1353         FileObject->SectionObjectPointer->SharedCacheMap = SharedCacheMap;
1354
1355         KeAcquireSpinLock(&iSharedCacheMapLock, &OldIrql);
1356         InsertTailList(&CcCleanSharedCacheMapList, &SharedCacheMap->SharedCacheMapLinks);
1357         KeReleaseSpinLock(&iSharedCacheMapLock, OldIrql);
1358     }
1359     if (FileObject->PrivateCacheMap == NULL)
1360     {
1361         FileObject->PrivateCacheMap = SharedCacheMap;
1362         SharedCacheMap->OpenCount++;
1363     }
1364     KeReleaseGuardedMutex(&ViewLock);
1365
1366     return STATUS_SUCCESS;
1367 }
1368
1369 /*
1370  * @implemented
1371  */
1372 PFILE_OBJECT
1373 NTAPI
1374 CcGetFileObjectFromSectionPtrs (
1375     IN PSECTION_OBJECT_POINTERS SectionObjectPointers)
1376 {
1377     PROS_SHARED_CACHE_MAP SharedCacheMap;
1378
1379     CCTRACE(CC_API_DEBUG, "SectionObjectPointers=%p\n", SectionObjectPointers);
1380
1381     if (SectionObjectPointers && SectionObjectPointers->SharedCacheMap)
1382     {
1383         SharedCacheMap = SectionObjectPointers->SharedCacheMap;
1384         ASSERT(SharedCacheMap);
1385         return SharedCacheMap->FileObject;
1386     }
1387     return NULL;
1388 }
1389
1390 VOID
1391 NTAPI
1392 CcShutdownLazyWriter (
1393     VOID)
1394 {
1395     /* Simply set the event, lazy writer will stop when it's done */
1396     KeSetEvent(&iLazyWriterShutdown, IO_DISK_INCREMENT, FALSE);
1397 }
1398
1399 BOOLEAN
1400 INIT_FUNCTION
1401 NTAPI
1402 CcInitView (
1403     VOID)
1404 {
1405     HANDLE LazyWriter;
1406     NTSTATUS Status;
1407     KPRIORITY Priority;
1408     OBJECT_ATTRIBUTES ObjectAttributes;
1409
1410     DPRINT("CcInitView()\n");
1411
1412     InitializeListHead(&DirtyVacbListHead);
1413     InitializeListHead(&VacbLruListHead);
1414     InitializeListHead(&CcDeferredWrites);
1415     InitializeListHead(&CcCleanSharedCacheMapList);
1416     KeInitializeSpinLock(&CcDeferredWriteSpinLock);
1417     KeInitializeSpinLock(&iSharedCacheMapLock);
1418     KeInitializeGuardedMutex(&ViewLock);
1419     ExInitializeNPagedLookasideList(&iBcbLookasideList,
1420                                     NULL,
1421                                     NULL,
1422                                     0,
1423                                     sizeof(INTERNAL_BCB),
1424                                     TAG_BCB,
1425                                     20);
1426     ExInitializeNPagedLookasideList(&SharedCacheMapLookasideList,
1427                                     NULL,
1428                                     NULL,
1429                                     0,
1430                                     sizeof(ROS_SHARED_CACHE_MAP),
1431                                     TAG_SHARED_CACHE_MAP,
1432                                     20);
1433     ExInitializeNPagedLookasideList(&VacbLookasideList,
1434                                     NULL,
1435                                     NULL,
1436                                     0,
1437                                     sizeof(ROS_VACB),
1438                                     TAG_VACB,
1439                                     20);
1440
1441     MmInitializeMemoryConsumer(MC_CACHE, CcRosTrimCache);
1442
1443     /* Initialize lazy writer events */
1444     KeInitializeEvent(&iLazyWriterShutdown, SynchronizationEvent, FALSE);
1445     KeInitializeEvent(&iLazyWriterNotify, NotificationEvent, FALSE);
1446
1447     /* Define lazy writer threshold, depending on system type */
1448     switch (MmQuerySystemSize())
1449     {
1450         case MmSmallSystem:
1451             CcDirtyPageThreshold = MmNumberOfPhysicalPages / 8;
1452             break;
1453
1454         case MmMediumSystem:
1455             CcDirtyPageThreshold = MmNumberOfPhysicalPages / 4;
1456             break;
1457
1458         case MmLargeSystem:
1459             CcDirtyPageThreshold = MmNumberOfPhysicalPages / 8 + MmNumberOfPhysicalPages / 4;
1460             break;
1461     }
1462
1463     /* Start the lazy writer thread */
1464     InitializeObjectAttributes(&ObjectAttributes,
1465                                NULL,
1466                                OBJ_KERNEL_HANDLE,
1467                                NULL,
1468                                NULL);
1469     Status = PsCreateSystemThread(&LazyWriter,
1470                                   THREAD_ALL_ACCESS,
1471                                   &ObjectAttributes,
1472                                   NULL,
1473                                   NULL,
1474                                   CciLazyWriter,
1475                                   NULL);
1476     if (!NT_SUCCESS(Status))
1477     {
1478         return FALSE;
1479     }
1480
1481     Priority = 27;
1482     Status = NtSetInformationThread(LazyWriter,
1483                                    ThreadPriority,
1484                                    &Priority,
1485                                    sizeof(Priority));
1486     ASSERT(NT_SUCCESS(Status));
1487
1488     /* Handle is not needed */
1489     ObCloseHandle(LazyWriter, KernelMode);
1490
1491     CcInitCacheZeroPage();
1492
1493     return TRUE;
1494 }
1495
1496 #if DBG && defined(KDBG)
1497 BOOLEAN
1498 ExpKdbgExtFileCache(ULONG Argc, PCHAR Argv[])
1499 {
1500     PLIST_ENTRY ListEntry;
1501     UNICODE_STRING NoName = RTL_CONSTANT_STRING(L"No name for File");
1502
1503     KdbpPrint("  Usage Summary (in kb)\n");
1504     KdbpPrint("Shared\t\tValid\tDirty\tName\n");
1505     /* No need to lock the spin lock here, we're in DBG */
1506     for (ListEntry = CcCleanSharedCacheMapList.Flink;
1507          ListEntry != &CcCleanSharedCacheMapList;
1508          ListEntry = ListEntry->Flink)
1509     {
1510         PLIST_ENTRY Vacbs;
1511         ULONG Valid = 0, Dirty = 0;
1512         PROS_SHARED_CACHE_MAP SharedCacheMap;
1513         PUNICODE_STRING FileName;
1514
1515         SharedCacheMap = CONTAINING_RECORD(ListEntry, ROS_SHARED_CACHE_MAP, SharedCacheMapLinks);
1516
1517         /* First, count for all the associated VACB */
1518         for (Vacbs = SharedCacheMap->CacheMapVacbListHead.Flink;
1519              Vacbs != &SharedCacheMap->CacheMapVacbListHead;
1520              Vacbs = Vacbs->Flink)
1521         {
1522             PROS_VACB Vacb;
1523
1524             Vacb = CONTAINING_RECORD(Vacbs, ROS_VACB, CacheMapVacbListEntry);
1525             if (Vacb->Dirty)
1526             {
1527                 Dirty += VACB_MAPPING_GRANULARITY / 1024;
1528             }
1529             if (Vacb->Valid)
1530             {
1531                 Valid += VACB_MAPPING_GRANULARITY / 1024;
1532             }
1533         }
1534
1535         /* Setup name */
1536         if (SharedCacheMap->FileObject != NULL &&
1537             SharedCacheMap->FileObject->FileName.Length != 0)
1538         {
1539             FileName = &SharedCacheMap->FileObject->FileName;
1540         }
1541         else
1542         {
1543             FileName = &NoName;
1544         }
1545
1546         /* And print */
1547         KdbpPrint("%p\t%d\t%d\t%wZ\n", SharedCacheMap, Valid, Dirty, FileName);
1548     }
1549
1550     return TRUE;
1551 }
1552 #endif
1553
1554 /* EOF */