arch/x86/include/asm/mem_encrypt.h

   1 /*
   2  * AMD Memory Encryption Support
   3  *
   4  * Copyright (C) 2016 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Tom Lendacky <thomas.lendacky@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #ifndef __X86_MEM_ENCRYPT_H__
  14 #define __X86_MEM_ENCRYPT_H__
  15
  16 #ifndef __ASSEMBLY__
  17
  18 #include <linux/init.h>
  19
  20 #ifdef CONFIG_AMD_MEM_ENCRYPT
  21
  22 extern unsigned long sme_me_mask;
  23
  24 void __init sme_early_encrypt(resource_size_t paddr,
  25                               unsigned long size);
  26 void __init sme_early_decrypt(resource_size_t paddr,
  27                               unsigned long size);
  28
  29 void __init sme_early_init(void);
  30
  31 void __init sme_encrypt_kernel(void);
  32 void __init sme_enable(void);
  33
  34 #else   /* !CONFIG_AMD_MEM_ENCRYPT */
  35
  36 #define sme_me_mask     0UL
  37
  38 static inline void __init sme_early_encrypt(resource_size_t paddr,
  39                                             unsigned long size) { }
  40 static inline void __init sme_early_decrypt(resource_size_t paddr,
  41                                             unsigned long size) { }
  42
  43 static inline void __init sme_early_init(void) { }
  44
  45 static inline void __init sme_encrypt_kernel(void) { }
  46 static inline void __init sme_enable(void) { }
  47
  48 #endif  /* CONFIG_AMD_MEM_ENCRYPT */
  49
  50 /*
  51  * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
  52  * writing to or comparing values from the cr3 register.  Having the
  53  * encryption mask set in cr3 enables the PGD entry to be encrypted and
  54  * avoid special case handling of PGD allocations.
  55  */
  56 #define __sme_pa(x)             (__pa(x) | sme_me_mask)
  57 #define __sme_pa_nodebug(x)     (__pa_nodebug(x) | sme_me_mask)
  58
  59 #endif  /* __ASSEMBLY__ */
  60
  61 #endif  /* __X86_MEM_ENCRYPT_H__ */