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 #include <asm/bootparam.h> 21 22 #ifdef CONFIG_AMD_MEM_ENCRYPT 23 24 extern u64 sme_me_mask; 25 extern bool sev_enabled; 26 27 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr, 28 unsigned long decrypted_kernel_vaddr, 29 unsigned long kernel_len, 30 unsigned long encryption_wa, 31 unsigned long encryption_pgd); 32 33 void __init sme_early_encrypt(resource_size_t paddr, 34 unsigned long size); 35 void __init sme_early_decrypt(resource_size_t paddr, 36 unsigned long size); 37 38 void __init sme_map_bootdata(char *real_mode_data); 39 void __init sme_unmap_bootdata(char *real_mode_data); 40 41 void __init sme_early_init(void); 42 43 void __init sme_encrypt_kernel(struct boot_params *bp); 44 void __init sme_enable(struct boot_params *bp); 45 46 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size); 47 int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size); 48 49 /* Architecture __weak replacement functions */ 50 void __init mem_encrypt_init(void); 51 void __init mem_encrypt_free_decrypted_mem(void); 52 53 bool sme_active(void); 54 bool sev_active(void); 55 56 #define __bss_decrypted __attribute__((__section__(".bss..decrypted"))) 57 58 #else /* !CONFIG_AMD_MEM_ENCRYPT */ 59 60 #define sme_me_mask 0ULL 61 62 static inline void __init sme_early_encrypt(resource_size_t paddr, 63 unsigned long size) { } 64 static inline void __init sme_early_decrypt(resource_size_t paddr, 65 unsigned long size) { } 66 67 static inline void __init sme_map_bootdata(char *real_mode_data) { } 68 static inline void __init sme_unmap_bootdata(char *real_mode_data) { } 69 70 static inline void __init sme_early_init(void) { } 71 72 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } 73 static inline void __init sme_enable(struct boot_params *bp) { } 74 75 static inline bool sme_active(void) { return false; } 76 static inline bool sev_active(void) { return false; } 77 78 static inline int __init 79 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } 80 static inline int __init 81 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; } 82 83 #define __bss_decrypted 84 85 #endif /* CONFIG_AMD_MEM_ENCRYPT */ 86 87 /* 88 * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when 89 * writing to or comparing values from the cr3 register. Having the 90 * encryption mask set in cr3 enables the PGD entry to be encrypted and 91 * avoid special case handling of PGD allocations. 92 */ 93 #define __sme_pa(x) (__pa(x) | sme_me_mask) 94 #define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask) 95 96 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[]; 97 98 #endif /* __ASSEMBLY__ */ 99 100 #endif /* __X86_MEM_ENCRYPT_H__ */ 101