ntoskrnl/mm/ARM3/zeropage.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         BSD - See COPYING.ARM in the top level directory
   4  * FILE:            ntoskrnl/mm/ARM3/zeropage.c
   5  * PURPOSE:         ARM Memory Manager Zero Page Thread Support
   6  * PROGRAMMERS:     ReactOS Portable Systems Group
   7  */
   8
   9 /* INCLUDES *******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 #define MODULE_INVOLVED_IN_ARM3
  16 #include <mm/ARM3/miarm.h>
  17
  18 /* GLOBALS ********************************************************************/
  19
  20 BOOLEAN MmZeroingPageThreadActive;
  21 KEVENT MmZeroingPageEvent;
  22
  23 /* PRIVATE FUNCTIONS **********************************************************/
  24
  25 VOID
  26 NTAPI
  27 MiFindInitializationCode(OUT PVOID *StartVa,
  28 OUT PVOID *EndVa);
  29
  30 VOID
  31 NTAPI
  32 MiFreeInitializationCode(IN PVOID StartVa,
  33 IN PVOID EndVa);
  34
  35 VOID
  36 NTAPI
  37 MmZeroPageThread(VOID)
  38 {
  39     PKTHREAD Thread = KeGetCurrentThread();
  40     PVOID StartAddress, EndAddress;
  41     PVOID WaitObjects[2];
  42     KIRQL OldIrql;
  43     PVOID ZeroAddress;
  44     PFN_NUMBER PageIndex, FreePage;
  45     PMMPFN Pfn1;
  46
  47     /* Get the discardable sections to free them */
  48     MiFindInitializationCode(&StartAddress, &EndAddress);
  49     if (StartAddress) MiFreeInitializationCode(StartAddress, EndAddress);
  50     DPRINT("Free non-cache pages: %lx\n", MmAvailablePages + MiMemoryConsumers[MC_CACHE].PagesUsed);
  51
  52     /* Set our priority to 0 */
  53     Thread->BasePriority = 0;
  54     KeSetPriorityThread(Thread, 0);
  55
  56     /* Setup the wait objects */
  57     WaitObjects[0] = &MmZeroingPageEvent;
  58 //    WaitObjects[1] = &PoSystemIdleTimer; FIXME: Implement idle timer
  59
  60     while (TRUE)
  61     {
  62         KeWaitForMultipleObjects(1, // 2
  63                                  WaitObjects,
  64                                  WaitAny,
  65                                  WrFreePage,
  66                                  KernelMode,
  67                                  FALSE,
  68                                  NULL,
  69                                  NULL);
  70         OldIrql = MiAcquirePfnLock();
  71         MmZeroingPageThreadActive = TRUE;
  72
  73         while (TRUE)
  74         {
  75             if (!MmFreePageListHead.Total)
  76             {
  77                 MmZeroingPageThreadActive = FALSE;
  78                 MiReleasePfnLock(OldIrql);
  79                 break;
  80             }
  81
  82             PageIndex = MmFreePageListHead.Flink;
  83             ASSERT(PageIndex != LIST_HEAD);
  84             Pfn1 = MiGetPfnEntry(PageIndex);
  85             MI_SET_USAGE(MI_USAGE_ZERO_LOOP);
  86             MI_SET_PROCESS2("Kernel 0 Loop");
  87             FreePage = MiRemoveAnyPage(MI_GET_PAGE_COLOR(PageIndex));
  88
  89             /* The first global free page should also be the first on its own list */
  90             if (FreePage != PageIndex)
  91             {
  92                 KeBugCheckEx(PFN_LIST_CORRUPT,
  93                              0x8F,
  94                              FreePage,
  95                              PageIndex,
  96                              0);
  97             }
  98
  99             Pfn1->u1.Flink = LIST_HEAD;
 100             MiReleasePfnLock(OldIrql);
 101
 102             ZeroAddress = MiMapPagesInZeroSpace(Pfn1, 1);
 103             ASSERT(ZeroAddress);
 104             RtlZeroMemory(ZeroAddress, PAGE_SIZE);
 105             MiUnmapPagesInZeroSpace(ZeroAddress, 1);
 106
 107             OldIrql = MiAcquirePfnLock();
 108
 109             MiInsertPageInList(&MmZeroedPageListHead, PageIndex);
 110         }
 111     }
 112 }
 113
 114 /* EOF */