arch/x86/mm/mem_encrypt.c

   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 #include <linux/linkage.h>
  14 #include <linux/init.h>
  15 #include <linux/mm.h>
  16
  17 /*
  18  * Since SME related variables are set early in the boot process they must
  19  * reside in the .data section so as not to be zeroed out when the .bss
  20  * section is later cleared.
  21  */
  22 unsigned long sme_me_mask __section(.data) = 0;
  23 EXPORT_SYMBOL_GPL(sme_me_mask);
  24
  25 void __init sme_early_init(void)
  26 {
  27         unsigned int i;
  28
  29         if (!sme_me_mask)
  30                 return;
  31
  32         early_pmd_flags = __sme_set(early_pmd_flags);
  33
  34         __supported_pte_mask = __sme_set(__supported_pte_mask);
  35
  36         /* Update the protection map with memory encryption mask */
  37         for (i = 0; i < ARRAY_SIZE(protection_map); i++)
  38                 protection_map[i] = pgprot_encrypted(protection_map[i]);
  39 }
  40
  41 void __init sme_encrypt_kernel(void)
  42 {
  43 }
  44
  45 void __init sme_enable(void)
  46 {
  47 }