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[HALX86:DMA] HACK: Avoid excessive stack usage

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CORE-17256
This commit is contained in:
Dmitry Borisov
2024-06-02 00:07:47 +06:00
committed by Carl J. Bialorucki
parent bd33d627b7
commit 5418987cb8
1 changed files with 17 additions and 2 deletions
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19
hal/halx86/generic/dma.c
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@@ -77,7 +77,8 @@
#define NDEBUG
#include <debug.h>
#define MAX_SG_ELEMENTS 0x10
// FIXME: This value needs to be calculated at runtime
#define MAX_SG_ELEMENTS 0x20
#ifndef _MINIHAL_
static KEVENT HalpDmaLock;
@@ -993,13 +994,24 @@ HalpScatterGatherAdapterControl(IN PDEVICE_OBJECT DeviceObject,
PSCATTER_GATHER_CONTEXT AdapterControlContext = Context;
PADAPTER_OBJECT AdapterObject = AdapterControlContext->AdapterObject;
PSCATTER_GATHER_LIST ScatterGatherList;
SCATTER_GATHER_ELEMENT TempElements[MAX_SG_ELEMENTS];
PSCATTER_GATHER_ELEMENT TempElements;
ULONG ElementCount = 0, RemainingLength = AdapterControlContext->Length;
PUCHAR CurrentVa = AdapterControlContext->CurrentVa;
/* Store the map register base for later in HalPutScatterGatherList */
AdapterControlContext->MapRegisterBase = MapRegisterBase;
// FIXME: HACK Allocate TempElements from pool to minimize stack usage.
// A more efficient algorithm should be found to avoid allocations during S/G I/O operations.
TempElements = ExAllocatePoolUninitialized(NonPagedPool,
sizeof(*TempElements) * MAX_SG_ELEMENTS,
TAG_DMA);
if (!TempElements)
{
DPRINT1("Scatter/gather list construction failed!\n");
return DeallocateObject;
}
while (RemainingLength > 0 && ElementCount < MAX_SG_ELEMENTS)
{
TempElements[ElementCount].Length = RemainingLength;
@@ -1025,6 +1037,7 @@ HalpScatterGatherAdapterControl(IN PDEVICE_OBJECT DeviceObject,
if (RemainingLength > 0)
{
DPRINT1("Scatter/gather list construction failed!\n");
ExFreePoolWithTag(TempElements, TAG_DMA);
return DeallocateObject;
}
@@ -1039,6 +1052,8 @@ HalpScatterGatherAdapterControl(IN PDEVICE_OBJECT DeviceObject,
TempElements,
sizeof(SCATTER_GATHER_ELEMENT) * ElementCount);
ExFreePoolWithTag(TempElements, TAG_DMA);
DPRINT("Initiating S/G DMA with %d element(s)\n", ElementCount);
AdapterControlContext->AdapterListControlRoutine(DeviceObject,