reactos/ntoskrnl/mm/ARM3/pool.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         BSD - See COPYING.ARM in the top level directory
   4  * FILE:            ntoskrnl/mm/ARM3/pool.c
   5  * PURPOSE:         ARM Memory Manager Pool Allocator
   6  * PROGRAMMERS:     ReactOS Portable Systems Group
   7  */
   8
   9 /* INCLUDES *******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 #line 15 "ARM³::POOL"
  16 #define MODULE_INVOLVED_IN_ARM3
  17 #include "../ARM3/miarm.h"
  18
  19 /* GLOBALS ********************************************************************/
  20
  21 LIST_ENTRY MmNonPagedPoolFreeListHead[MI_MAX_FREE_PAGE_LISTS];
  22 PFN_NUMBER MmNumberOfFreeNonPagedPool, MiExpansionPoolPagesInitialCharge;
  23 PVOID MmNonPagedPoolEnd0;
  24 PFN_NUMBER MiStartOfInitialPoolFrame, MiEndOfInitialPoolFrame;
  25
  26 /* PRIVATE FUNCTIONS **********************************************************/
  27
  28 VOID
  29 NTAPI
  30 MiInitializeArmPool(VOID)
  31 {
  32     ULONG i;
  33     PFN_NUMBER PoolPages;
  34     PMMFREE_POOL_ENTRY FreeEntry, FirstEntry;
  35     PMMPTE PointerPte;
  36     PAGED_CODE();
  37
  38     //
  39     // We keep 4 lists of free pages (4 lists help avoid contention)
  40     //
  41     for (i = 0; i < MI_MAX_FREE_PAGE_LISTS; i++)
  42     {
  43         //
  44         // Initialize each of them
  45         //
  46         InitializeListHead(&MmNonPagedPoolFreeListHead[i]);
  47     }
  48
  49     //
  50     // Calculate how many pages the initial nonpaged pool has
  51     //
  52     PoolPages = BYTES_TO_PAGES(MmSizeOfNonPagedPoolInBytes);
  53     MmNumberOfFreeNonPagedPool = PoolPages;
  54
  55     //
  56     // Initialize the first free entry
  57     //
  58     FreeEntry = MmNonPagedPoolStart;
  59     FirstEntry = FreeEntry;
  60     FreeEntry->Size = PoolPages;
  61     FreeEntry->Owner = FirstEntry;
  62
  63     //
  64     // Insert it into the last list
  65     //
  66     InsertHeadList(&MmNonPagedPoolFreeListHead[MI_MAX_FREE_PAGE_LISTS - 1],
  67                    &FreeEntry->List);
  68
  69     //
  70     // Now create free entries for every single other page
  71     //
  72     while (PoolPages-- > 1)
  73     {
  74         //
  75         // Link them all back to the original entry
  76         //
  77         FreeEntry = (PMMFREE_POOL_ENTRY)((ULONG_PTR)FreeEntry + PAGE_SIZE);
  78         FreeEntry->Owner = FirstEntry;
  79     }
  80
  81     //
  82     // Validate and remember first allocated pool page
  83     //
  84     PointerPte = MiAddressToPte(MmNonPagedPoolStart);
  85     ASSERT(PointerPte->u.Hard.Valid == 1);
  86     MiStartOfInitialPoolFrame = PFN_FROM_PTE(PointerPte);
  87
  88     //
  89     // Keep track of where initial nonpaged pool ends
  90     //
  91     MmNonPagedPoolEnd0 = (PVOID)((ULONG_PTR)MmNonPagedPoolStart +
  92                                  MmSizeOfNonPagedPoolInBytes);
  93
  94     //
  95     // Validate and remember last allocated pool page
  96     //
  97     PointerPte = MiAddressToPte((PVOID)((ULONG_PTR)MmNonPagedPoolEnd0 - 1));
  98     ASSERT(PointerPte->u.Hard.Valid == 1);
  99     MiEndOfInitialPoolFrame = PFN_FROM_PTE(PointerPte);
 100
 101     //
 102     // Validate the first nonpaged pool expansion page (which is a guard page)
 103     //
 104     PointerPte = MiAddressToPte(MmNonPagedPoolExpansionStart);
 105     ASSERT(PointerPte->u.Hard.Valid == 0);
 106
 107     //
 108     // Calculate the size of the expansion region alone
 109     //
 110     MiExpansionPoolPagesInitialCharge =
 111     BYTES_TO_PAGES(MmMaximumNonPagedPoolInBytes - MmSizeOfNonPagedPoolInBytes);
 112
 113     //
 114     // Remove 2 pages, since there's a guard page on top and on the bottom
 115     //
 116     MiExpansionPoolPagesInitialCharge -= 2;
 117
 118     //
 119     // Now initialize the nonpaged pool expansion PTE space. Remember there's a
 120     // guard page on top so make sure to skip it. The bottom guard page will be
 121     // guaranteed by the fact our size is off by one.
 122     //
 123     MiInitializeSystemPtes(PointerPte + 1,
 124                            MiExpansionPoolPagesInitialCharge,
 125                            NonPagedPoolExpansion);
 126 }
 127
 128 /* EOF */