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IntelFrameworkModulePkg/LegacyBios: Use macro to enable/disable page 0

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Current implementation uses following two methods

    EnableNullDetection()
    DisableNullDetection()

to enable/disable page 0. These two methods will check PCD
PcdNullPointerDetectionPropertyMask to know if the page 0 is disabled or not.
This is due to the fact that old GCD service doesn't provide paging related
attributes of memory block. Since this issue has been fixed, GCD services
can be used to determine the paging status of page 0. This is also make it
possible to just use a new macro

    ACCESS_PAGE0_CODE(
      <code accessing page 0>
    );

to replace above methods to do the same job, which also makes code more
readability.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
This commit is contained in:
Jian J Wang
2017-12-07 17:00:23 +08:00
committed by Star Zeng
parent 7619eed8aa
commit 2ea3576e16
7 changed files with 135 additions and 273 deletions
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135
IntelFrameworkModulePkg/Csm/LegacyBiosDxe/LegacyBios.c
View File

@@ -786,115 +786,6 @@ ToggleEndOfDxeStatus (
return;
}
//
// Legacy BIOS needs to access memory between 0-4095, which will cause page
// fault exception if NULL pointer detection mechanism is enabled. Following
// functions can be used to disable/enable NULL pointer detection before/after
// accessing those memory.
//
/**
Enable NULL pointer detection.
**/
VOID
EnableNullDetection (
VOID
)
{
EFI_STATUS Status;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR Desc;
if (((PcdGet8 (PcdNullPointerDetectionPropertyMask) & BIT0) == 0)
||
((mEndOfDxe) &&
((PcdGet8 (PcdNullPointerDetectionPropertyMask) & (BIT7|BIT0))
== (BIT7|BIT0)))
) {
return;
}
//
// Check current capabilities and attributes
//
Status = gDS->GetMemorySpaceDescriptor (0, &Desc);
ASSERT_EFI_ERROR (Status);
//
// Try to add EFI_MEMORY_RP support if necessary
//
if ((Desc.Capabilities & EFI_MEMORY_RP) == 0) {
Desc.Capabilities |= EFI_MEMORY_RP;
Status = gDS->SetMemorySpaceCapabilities (0, EFI_PAGES_TO_SIZE(1),
Desc.Capabilities);
ASSERT_EFI_ERROR (Status);
if (EFI_ERROR (Status)) {
return;
}
}
//
// Don't bother if EFI_MEMORY_RP is already set.
//
if ((Desc.Attributes & EFI_MEMORY_RP) == 0) {
Desc.Attributes |= EFI_MEMORY_RP;
Status = gDS->SetMemorySpaceAttributes (0, EFI_PAGES_TO_SIZE(1),
Desc.Attributes);
ASSERT_EFI_ERROR (Status);
}
}
/**
Disable NULL pointer detection.
**/
VOID
DisableNullDetection (
VOID
)
{
EFI_STATUS Status;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR Desc;
if (((PcdGet8 (PcdNullPointerDetectionPropertyMask) & BIT0) == 0)
||
((mEndOfDxe) &&
((PcdGet8 (PcdNullPointerDetectionPropertyMask) & (BIT7|BIT0))
== (BIT7|BIT0)))
) {
return;
}
//
// Check current capabilities and attributes
//
Status = gDS->GetMemorySpaceDescriptor (0, &Desc);
ASSERT_EFI_ERROR (Status);
//
// Try to add EFI_MEMORY_RP support if necessary
//
if ((Desc.Capabilities & EFI_MEMORY_RP) == 0) {
Desc.Capabilities |= EFI_MEMORY_RP;
Status = gDS->SetMemorySpaceCapabilities (0, EFI_PAGES_TO_SIZE(1),
Desc.Capabilities);
ASSERT_EFI_ERROR (Status);
if (EFI_ERROR (Status)) {
return;
}
}
//
// Don't bother if EFI_MEMORY_RP is already cleared.
//
if ((Desc.Attributes & EFI_MEMORY_RP) != 0) {
Desc.Attributes &= ~EFI_MEMORY_RP;
Status = gDS->SetMemorySpaceAttributes (0, EFI_PAGES_TO_SIZE(1),
Desc.Attributes);
ASSERT_EFI_ERROR (Status);
} else {
DEBUG ((DEBUG_WARN, "!!! Page 0 is supposed to be disabled !!!\r\n"));
}
}
/**
Install Driver to produce Legacy BIOS protocol.
@@ -1095,10 +986,10 @@ LegacyBiosInstall (
// Initialize region from 0x0000 to 4k. This initializes interrupt vector
// range.
//
DisableNullDetection ();
gBS->SetMem ((VOID *) ClearPtr, 0x400, INITIAL_VALUE_BELOW_1K);
ZeroMem ((VOID *) ((UINTN)ClearPtr + 0x400), 0xC00);
EnableNullDetection ();
ACCESS_PAGE0_CODE (
gBS->SetMem ((VOID *) ClearPtr, 0x400, INITIAL_VALUE_BELOW_1K);
ZeroMem ((VOID *) ((UINTN)ClearPtr + 0x400), 0xC00);
);
//
// Allocate pages for OPROM usage
@@ -1237,16 +1128,14 @@ LegacyBiosInstall (
//
// Save Unexpected interrupt vector so can restore it just prior to boot
//
DisableNullDetection ();
BaseVectorMaster = (UINT32 *) (sizeof (UINT32) * PROTECTED_MODE_BASE_VECTOR_MASTER);
Private->BiosUnexpectedInt = BaseVectorMaster[0];
IntRedirCode = (UINT32) (UINTN) Private->IntThunk->InterruptRedirectionCode;
for (Index = 0; Index < 8; Index++) {
BaseVectorMaster[Index] = (EFI_SEGMENT (IntRedirCode + Index * 4) << 16) | EFI_OFFSET (IntRedirCode + Index * 4);
}
EnableNullDetection ();
ACCESS_PAGE0_CODE (
BaseVectorMaster = (UINT32 *) (sizeof (UINT32) * PROTECTED_MODE_BASE_VECTOR_MASTER);
Private->BiosUnexpectedInt = BaseVectorMaster[0];
IntRedirCode = (UINT32) (UINTN) Private->IntThunk->InterruptRedirectionCode;
for (Index = 0; Index < 8; Index++) {
BaseVectorMaster[Index] = (EFI_SEGMENT (IntRedirCode + Index * 4) << 16) | EFI_OFFSET (IntRedirCode + Index * 4);
}
);
//
// Save EFI value