RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429 Add Intel Tdx helper library. The library provides the routines to: - set or clear Shared bit for a given memory region. - query whether TDX is enabled. Please be noted, there a lot of duplicated codes for Page Table operations. These codes should be moved to a common library (PageTablesLib) so that it is more friendly for review and maintain. There is a new feature requirement https://bugzilla.tianocore.org/show_bug.cgi?id=847 which is to implement the library. After the lib is introduced, BaseMemEncryptTdxLib will be refactored. Cc: Ard Biesheuvel <ardb+tianocore@kernel.org> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Erdem Aktas <erdemaktas@google.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com> Signed-off-by: Min Xu <min.m.xu@intel.com>
		
			
				
	
	
		
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			91 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /** @file
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| 
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|   Virtual Memory Management Services to set or clear the memory encryption
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| 
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|   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
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|   Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
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| 
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|   SPDX-License-Identifier: BSD-2-Clause-Patent
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| 
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|   Code is derived from MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
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| 
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| **/
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| 
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| #include <Uefi.h>
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| #include <Uefi/UefiBaseType.h>
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| #include <Library/BaseLib.h>
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| #include <Library/MemEncryptTdxLib.h>
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| 
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| /**
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|   Returns boolean to indicate whether to indicate which, if any, memory encryption is enabled
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| 
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|   @param[in]  Type          Bitmask of encryption technologies to check is enabled
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| 
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|   @retval TRUE              The encryption type(s) are enabled
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|   @retval FALSE             The encryption type(s) are not enabled
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| **/
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| BOOLEAN
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| EFIAPI
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| MemEncryptTdxIsEnabled (
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|   VOID
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|   )
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| {
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|   return FALSE;
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| }
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| 
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| /**
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|   This function clears memory encryption bit for the memory region specified by
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|   BaseAddress and NumPages from the current page table context.
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| 
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|   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
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|                                       current CR3)
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|   @param[in]  BaseAddress             The physical address that is the start
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|                                       address of a memory region.
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|   @param[in]  NumPages                The number of pages from start memory
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|                                       region.
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| 
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|   @retval RETURN_SUCCESS              The attributes were cleared for the
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|                                       memory region.
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|   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
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|   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
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|                                       is not supported
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| **/
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| RETURN_STATUS
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| EFIAPI
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| MemEncryptTdxSetPageSharedBit (
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|   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
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|   IN PHYSICAL_ADDRESS  BaseAddress,
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|   IN UINTN             NumPages
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|   )
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| {
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|   return EFI_UNSUPPORTED;
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| }
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| 
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| /**
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|   This function sets memory encryption bit for the memory region specified by
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|   BaseAddress and NumPages from the current page table context.
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| 
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|   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
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|                                       current CR3)
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|   @param[in]  BaseAddress             The physical address that is the start
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|                                       address of a memory region.
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|   @param[in]  NumPages                The number of pages from start memory
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|                                       region.
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| 
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|   @retval RETURN_SUCCESS              The attributes were set for the memory
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|                                       region.
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|   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
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|   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
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|                                       is not supported
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| **/
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| RETURN_STATUS
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| EFIAPI
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| MemEncryptTdxClearPageSharedBit (
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|   IN PHYSICAL_ADDRESS  Cr3BaseAddress,
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|   IN PHYSICAL_ADDRESS  BaseAddress,
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|   IN UINTN             NumPages
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|   )
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| {
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|   return EFI_UNSUPPORTED;
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| }
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