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* Fixed the allocation length for the mdl bitmap.

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* Changed the bit allocation functions to RtlXxxBitMapYyy.
* Fixed the calculation of the starting point for free bitmap entries.

svn path=/trunk/; revision=3703
This commit is contained in:
Hartmut Birr 2002-11-05 20:45:09 +00:00
parent ef586c33c1
commit ffadffc82b
1 changed files with 36 additions and 27 deletions
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63
reactos/ntoskrnl/mm/mdl.c
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@ -1,4 +1,4 @@
/* $Id: mdl.c,v 1.45 2002/10/01 19:27:22 chorns Exp $
/* $Id: mdl.c,v 1.46 2002/11/05 20:45:09 hbirr Exp $
*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
@ -15,6 +15,7 @@
#include <internal/mm.h>
#include <internal/ps.h>
#include <internal/pool.h>
#include <ntos/minmax.h>
#define NDEBUG
#include <internal/debug.h>
@ -26,8 +27,8 @@
#define MI_MDL_MAPPING_REGION_SIZE (256*1024*1024)
static PVOID MiMdlMappingRegionBase = NULL;
static PULONG MiMdlMappingRegionAllocMap = NULL;
static ULONG MiMdlMappingRegionHighWaterMark = 0;
static RTL_BITMAP MiMdlMappingRegionAllocMap;
static ULONG MiMdlMappingRegionHint;
static KSPIN_LOCK MiMdlMappingRegionLock;
/* FUNCTIONS *****************************************************************/
@ -37,7 +38,9 @@ MmInitializeMdlImplementation(VOID)
{
MEMORY_AREA* Result;
NTSTATUS Status;
PVOID Buffer;
MiMdlMappingRegionHint = 0;
MiMdlMappingRegionBase = NULL;
MmLockAddressSpace(MmGetKernelAddressSpace());
@ -56,10 +59,11 @@ MmInitializeMdlImplementation(VOID)
}
MmUnlockAddressSpace(MmGetKernelAddressSpace());
MiMdlMappingRegionAllocMap =
ExAllocatePool(NonPagedPool,
MI_MDL_MAPPING_REGION_SIZE / (PAGE_SIZE * 32));
MiMdlMappingRegionHighWaterMark = 0;
Buffer = ExAllocatePool(NonPagedPool, MI_MDL_MAPPING_REGION_SIZE / (PAGE_SIZE * 8));
RtlInitializeBitMap(&MiMdlMappingRegionAllocMap, Buffer, MI_MDL_MAPPING_REGION_SIZE / PAGE_SIZE);
RtlClearAllBits(&MiMdlMappingRegionAllocMap);
KeInitializeSpinLock(&MiMdlMappingRegionLock);
}
@ -130,6 +134,7 @@ MmMapLockedPages(PMDL Mdl, KPROCESSOR_MODE AccessMode)
PULONG MdlPages;
KIRQL oldIrql;
ULONG RegionSize;
ULONG StartingOffset;
DPRINT("MmMapLockedPages(Mdl %x, AccessMode %x)\n", Mdl, AccessMode);
@ -149,13 +154,22 @@ MmMapLockedPages(PMDL Mdl, KPROCESSOR_MODE AccessMode)
/* Allocate that number of pages from the mdl mapping region. */
KeAcquireSpinLock(&MiMdlMappingRegionLock, &oldIrql);
Base = MiMdlMappingRegionBase + MiMdlMappingRegionHighWaterMark * PAGE_SIZE;
for (i = 0; i < RegionSize; i++)
{
ULONG Offset = MiMdlMappingRegionHighWaterMark + i;
MiMdlMappingRegionAllocMap[Offset / 32] |= (1 << (Offset % 32));
}
MiMdlMappingRegionHighWaterMark += RegionSize;
StartingOffset = RtlFindClearBitsAndSet(&MiMdlMappingRegionAllocMap, RegionSize, MiMdlMappingRegionHint);
if (StartingOffset == 0xffffffff)
{
DPRINT1("Out of MDL mapping space\n");
KeBugCheck(0);
}
Base = MiMdlMappingRegionBase + StartingOffset * PAGE_SIZE;
if (MiMdlMappingRegionHint == StartingOffset)
{
MiMdlMappingRegionHint +=RegionSize;
}
KeReleaseSpinLock(&MiMdlMappingRegionLock, oldIrql);
/* Set the virtual mappings for the MDL pages. */
@ -195,7 +209,7 @@ MmUnmapLockedPages(PVOID BaseAddress, PMDL Mdl)
ULONG RegionSize;
ULONG Base;
DPRINT("MmUnmapLockedPages(BaseAddress %x, Mdl %x)\n", Mdl, BaseAddress);
DPRINT("MmUnmapLockedPages(BaseAddress %x, Mdl %x)\n", BaseAddress, Mdl);
/*
* In this case, the MDL has the same system address as the base address
@ -208,6 +222,7 @@ MmUnmapLockedPages(PVOID BaseAddress, PMDL Mdl)
/* Calculate the number of pages we mapped. */
RegionSize = PAGE_ROUND_UP(Mdl->ByteCount + Mdl->ByteOffset) / PAGE_SIZE;
BaseAddress -= Mdl->ByteOffset;
/* Unmap all the pages. */
for (i = 0; i < RegionSize; i++)
@ -221,18 +236,12 @@ MmUnmapLockedPages(PVOID BaseAddress, PMDL Mdl)
KeAcquireSpinLock(&MiMdlMappingRegionLock, &oldIrql);
/* Deallocate all the pages used. */
Base = (ULONG)(BaseAddress - MiMdlMappingRegionBase - Mdl->ByteOffset);
Base = Base / PAGE_SIZE;
for (i = 0; i < RegionSize; i++)
{
ULONG Offset = Base + i;
MiMdlMappingRegionAllocMap[Offset / 32] &= ~(1 << (Offset % 32));
}
/* If all the pages below the high-water mark are free then move it down. */
if ((Base + RegionSize) == MiMdlMappingRegionHighWaterMark)
{
MiMdlMappingRegionHighWaterMark = Base;
}
Base = (ULONG)(BaseAddress - MiMdlMappingRegionBase) / PAGE_SIZE;
RtlClearBits(&MiMdlMappingRegionAllocMap, Base, RegionSize);
MiMdlMappingRegionHint = min (MiMdlMappingRegionHint, Base);
KeReleaseSpinLock(&MiMdlMappingRegionLock, oldIrql);
/* Reset the MDL state. */