diff options
Diffstat (limited to 'OvmfPkg/IoMmuDxe/IoMmuBuffer.c')
| -rw-r--r-- | OvmfPkg/IoMmuDxe/IoMmuBuffer.c | 100 |
1 files changed, 59 insertions, 41 deletions
diff --git a/OvmfPkg/IoMmuDxe/IoMmuBuffer.c b/OvmfPkg/IoMmuDxe/IoMmuBuffer.c index 103003c..f8dcd5b 100644 --- a/OvmfPkg/IoMmuDxe/IoMmuBuffer.c +++ b/OvmfPkg/IoMmuDxe/IoMmuBuffer.c @@ -12,6 +12,7 @@ #include <Library/MemEncryptSevLib.h>
#include <Library/MemEncryptTdxLib.h>
#include <Library/PcdLib.h>
+#include <Library/SynchronizationLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include "IoMmuInternal.h"
@@ -268,16 +269,17 @@ InternalAllocateBuffer ( IN EFI_ALLOCATE_TYPE Type,
IN EFI_MEMORY_TYPE MemoryType,
IN UINTN Pages,
- IN OUT UINT32 *ReservedMemBitmap,
+ OUT UINT32 *ReservedMemBit,
IN OUT EFI_PHYSICAL_ADDRESS *PhysicalAddress
)
{
UINT32 MemBitmap;
+ UINT32 ReservedMemBitmap;
UINT8 Index;
IOMMU_RESERVED_MEM_RANGE *MemRange;
UINTN PagesOfLastMemRange;
- *ReservedMemBitmap = 0;
+ *ReservedMemBit = 0;
if (Pages == 0) {
ASSERT (FALSE);
@@ -309,23 +311,31 @@ InternalAllocateBuffer ( MemRange = &mReservedMemRanges[Index];
- if ((mReservedMemBitmap & MemRange->BitmapMask) == MemRange->BitmapMask) {
- // The reserved memory is exausted. Turn to legacy allocate.
- goto LegacyAllocateBuffer;
- }
+ do {
+ ReservedMemBitmap = mReservedMemBitmap;
+
+ if ((ReservedMemBitmap & MemRange->BitmapMask) == MemRange->BitmapMask) {
+ // The reserved memory is exhausted. Turn to legacy allocate.
+ goto LegacyAllocateBuffer;
+ }
- MemBitmap = (mReservedMemBitmap & MemRange->BitmapMask) >> MemRange->Shift;
+ MemBitmap = (ReservedMemBitmap & MemRange->BitmapMask) >> MemRange->Shift;
- for (Index = 0; Index < MemRange->Slots; Index++) {
- if ((MemBitmap & (UINT8)(1<<Index)) == 0) {
- break;
+ for (Index = 0; Index < MemRange->Slots; Index++) {
+ if ((MemBitmap & (UINT8)(1<<Index)) == 0) {
+ break;
+ }
}
- }
- ASSERT (Index != MemRange->Slots);
+ ASSERT (Index != MemRange->Slots);
- *PhysicalAddress = MemRange->StartAddressOfMemRange + Index * SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize;
- *ReservedMemBitmap = (UINT32)(1 << (Index + MemRange->Shift));
+ *PhysicalAddress = MemRange->StartAddressOfMemRange + Index * SIZE_OF_MEM_RANGE (MemRange) + MemRange->HeaderSize;
+ *ReservedMemBit = (UINT32)(1 << (Index + MemRange->Shift));
+ } while (ReservedMemBitmap != InterlockedCompareExchange32 (
+ &mReservedMemBitmap,
+ ReservedMemBitmap,
+ ReservedMemBitmap | *ReservedMemBit
+ ));
DEBUG ((
DEBUG_VERBOSE,
@@ -334,16 +344,16 @@ InternalAllocateBuffer ( MemRange->DataSize,
*PhysicalAddress,
Pages,
- *ReservedMemBitmap,
- mReservedMemBitmap,
- mReservedMemBitmap | *ReservedMemBitmap
+ *ReservedMemBit,
+ ReservedMemBitmap,
+ ReservedMemBitmap | *ReservedMemBit
));
return EFI_SUCCESS;
LegacyAllocateBuffer:
- *ReservedMemBitmap = 0;
+ *ReservedMemBit = 0;
return gBS->AllocatePages (Type, MemoryType, Pages, PhysicalAddress);
}
@@ -366,28 +376,42 @@ IoMmuAllocateBounceBuffer ( )
{
EFI_STATUS Status;
- UINT32 ReservedMemBitmap;
- EFI_TPL OldTpl;
-
- OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
- ReservedMemBitmap = 0;
- Status = InternalAllocateBuffer (
- Type,
- MemoryType,
- MapInfo->NumberOfPages,
- &ReservedMemBitmap,
- &MapInfo->PlainTextAddress
- );
- MapInfo->ReservedMemBitmap = ReservedMemBitmap;
- mReservedMemBitmap |= ReservedMemBitmap;
- gBS->RestoreTPL (OldTpl);
+ Status = InternalAllocateBuffer (
+ Type,
+ MemoryType,
+ MapInfo->NumberOfPages,
+ &MapInfo->ReservedMemBitmap,
+ &MapInfo->PlainTextAddress
+ );
ASSERT (Status == EFI_SUCCESS);
return Status;
}
/**
+ * Clear a bit in the reserved memory bitmap in a thread safe manner
+ *
+ * @param ReservedMemBit The bit to clear
+ */
+STATIC
+VOID
+ClearReservedMemBit (
+ IN UINT32 ReservedMemBit
+ )
+{
+ UINT32 ReservedMemBitmap;
+
+ do {
+ ReservedMemBitmap = mReservedMemBitmap;
+ } while (ReservedMemBitmap != InterlockedCompareExchange32 (
+ &mReservedMemBitmap,
+ ReservedMemBitmap,
+ ReservedMemBitmap & ~ReservedMemBit
+ ));
+}
+
+/**
* Free the bounce buffer allocated in IoMmuAllocateBounceBuffer.
*
* @param MapInfo Pointer to the MAP_INFO
@@ -398,8 +422,6 @@ IoMmuFreeBounceBuffer ( IN OUT MAP_INFO *MapInfo
)
{
- EFI_TPL OldTpl;
-
if (MapInfo->ReservedMemBitmap == 0) {
gBS->FreePages (MapInfo->PlainTextAddress, MapInfo->NumberOfPages);
} else {
@@ -412,11 +434,9 @@ IoMmuFreeBounceBuffer ( mReservedMemBitmap,
mReservedMemBitmap & ((UINT32)(~MapInfo->ReservedMemBitmap))
));
- OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
+ ClearReservedMemBit (MapInfo->ReservedMemBitmap);
MapInfo->PlainTextAddress = 0;
- mReservedMemBitmap &= (UINT32)(~MapInfo->ReservedMemBitmap);
MapInfo->ReservedMemBitmap = 0;
- gBS->RestoreTPL (OldTpl);
}
return EFI_SUCCESS;
@@ -452,8 +472,6 @@ IoMmuAllocateCommonBuffer ( );
ASSERT (Status == EFI_SUCCESS);
- mReservedMemBitmap |= *ReservedMemBitmap;
-
if (*ReservedMemBitmap != 0) {
*PhysicalAddress -= SIZE_4KB;
}
@@ -494,7 +512,7 @@ IoMmuFreeCommonBuffer ( mReservedMemBitmap & ((UINT32)(~CommonBufferHeader->ReservedMemBitmap))
));
- mReservedMemBitmap &= (UINT32)(~CommonBufferHeader->ReservedMemBitmap);
+ ClearReservedMemBit (CommonBufferHeader->ReservedMemBitmap);
return EFI_SUCCESS;
LegacyFreeCommonBuffer:
|