reactos/ntoskrnl/ex/zone.c

   1 /*
   2  * COPYRIGHT:       See COPYING in the top level directory
   3  * PROJECT:         ReactOS kernel
   4  * FILE:            ntoskrnl/ex/zone.c
   5  * PURPOSE:         Implements zone buffers
   6  *
   7  * PROGRAMMERS:     Alex Ionescu (alex@relsoft.net)
   8  *                  David Welch (welch@mcmail.com)
   9  */
  10
  11 /* INCLUDES ****************************************************************/
  12
  13 #include <ntoskrnl.h>
  14 #define NDEBUG
  15 #include <debug.h>
  16
  17 /* FUNCTIONS ***************************************************************/
  18
  19 /*
  20  * @implemented
  21  */
  22 NTSTATUS
  23 STDCALL
  24 ExExtendZone(PZONE_HEADER Zone,
  25              PVOID Segment,
  26              ULONG SegmentSize)
  27 {
  28     ULONG_PTR Entry;
  29     ULONG i;
  30
  31     /*
  32      * BlockSize and Segment must be 8-byte aligned.
  33      * Blocksize cannot exceed Segment Size.
  34      */
  35     if (((ULONG_PTR)Segment & 7) ||
  36         (SegmentSize & 7) ||
  37         (Zone->BlockSize > SegmentSize))
  38     {
  39         DPRINT1("Invalid ExExtendZone Alignment and/or Size\n");
  40         return STATUS_INVALID_PARAMETER;
  41     }
  42
  43     /* Link the Zone and Segment */
  44     PushEntryList(&Zone->SegmentList,&((PZONE_SEGMENT_HEADER)Segment)->SegmentList);
  45
  46     /* Get to the first entry */
  47     Entry = (ULONG_PTR)Segment + sizeof(ZONE_SEGMENT_HEADER);
  48
  49     /* Loop through the segments */
  50     for (i = sizeof(ZONE_SEGMENT_HEADER);
  51          i <= SegmentSize - Zone->BlockSize;
  52          i+= Zone->BlockSize)
  53     {
  54         /* Link the Free and Segment Lists */
  55         PushEntryList(&Zone->FreeList, (PSINGLE_LIST_ENTRY)Entry);
  56
  57         /* Go to the next entry */
  58         Entry += Zone->BlockSize;
  59     }
  60
  61     /* Update Segment Size */
  62     Zone->TotalSegmentSize += i;
  63
  64     /* Return Success */
  65     return STATUS_SUCCESS;
  66 }
  67
  68
  69 /*
  70  * @implemented
  71  */
  72 NTSTATUS
  73 STDCALL
  74 ExInterlockedExtendZone(PZONE_HEADER Zone,
  75                         PVOID Segment,
  76                         ULONG SegmentSize,
  77                         PKSPIN_LOCK     Lock)
  78 {
  79     NTSTATUS Status;
  80     KIRQL OldIrql;
  81
  82     /* Get the lock */
  83     KeAcquireSpinLock(Lock, &OldIrql);
  84
  85     /* Extend the Zone */
  86     Status = ExExtendZone(Zone, Segment, SegmentSize);
  87
  88     /* Release lock and return status */
  89     KeReleaseSpinLock(Lock, OldIrql);
  90     return Status;
  91 }
  92
  93
  94 /*
  95  * FUNCTION: Initalizes a zone header
  96  * ARGUMENTS:
  97  *          Zone = zone header to be initialized
  98  *          BlockSize = Size (in bytes) of the allocation size of the zone
  99  *          InitialSegment = Initial segment of storage allocated by the
 100  *                           caller
 101  *          InitialSegmentSize = Initial size of the segment
 102  *
 103  * @implemented
 104  */
 105 NTSTATUS
 106 STDCALL
 107 ExInitializeZone(PZONE_HEADER Zone,
 108                  ULONG BlockSize,
 109                  PVOID InitialSegment,
 110                  ULONG InitialSegmentSize)
 111 {
 112     ULONG i;
 113     ULONG_PTR Entry;
 114
 115     /*
 116      * BlockSize and Segment must be 8-byte aligned.
 117      * Blocksize cannot exceed Segment Size.
 118      */
 119     if (((ULONG_PTR)InitialSegment & 7) ||
 120         (InitialSegmentSize & 7) ||
 121         (BlockSize > InitialSegmentSize))
 122     {
 123         DPRINT1("Invalid ExInitializeZone Alignment and/or Size\n");
 124         return STATUS_INVALID_PARAMETER;
 125     }
 126
 127     /* Set the Zone Header */
 128     Zone->BlockSize = BlockSize;
 129
 130     /* Link empty list */
 131     Zone->FreeList.Next = NULL;
 132     Zone->SegmentList.Next = NULL;
 133     PushEntryList(&Zone->SegmentList, &((PZONE_SEGMENT_HEADER)InitialSegment)->SegmentList);
 134     ((PZONE_SEGMENT_HEADER)InitialSegment)->Reserved = NULL;
 135
 136     /* Get first entry */
 137     Entry = (ULONG_PTR)InitialSegment + sizeof(ZONE_SEGMENT_HEADER);
 138
 139     /* Loop through the segments */
 140     for (i = sizeof(ZONE_SEGMENT_HEADER);
 141          i <= InitialSegmentSize - BlockSize;
 142          i+= BlockSize)
 143     {
 144         /* Link the Free and Segment Lists */
 145         PushEntryList(&Zone->FreeList, (PSINGLE_LIST_ENTRY)Entry);
 146
 147         /* Go to the next entry */
 148         Entry += Zone->BlockSize;
 149     }
 150
 151     /* Update Segment Size */
 152     Zone->TotalSegmentSize += i;
 153
 154     /* Return success */
 155     return STATUS_SUCCESS;
 156 }
 157
 158 /* EOF */