1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * AMD Memory Encryption Support 4 * 5 * Copyright (C) 2016 Advanced Micro Devices, Inc. 6 * 7 * Author: Tom Lendacky <thomas.lendacky@amd.com> 8 */ 9 10 #ifndef __X86_MEM_ENCRYPT_H__ 11 #define __X86_MEM_ENCRYPT_H__ 12 13 #ifndef __ASSEMBLY__ 14 15 #include <linux/init.h> 16 17 #include <asm/bootparam.h> 18 19 #ifdef CONFIG_AMD_MEM_ENCRYPT 20 21 extern u64 sme_me_mask; 22 extern bool sev_enabled; 23 24 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr, 25 unsigned long decrypted_kernel_vaddr, 26 unsigned long kernel_len, 27 unsigned long encryption_wa, 28 unsigned long encryption_pgd); 29 30 void __init sme_early_encrypt(resource_size_t paddr, 31 unsigned long size); 32 void __init sme_early_decrypt(resource_size_t paddr, 33 unsigned long size); 34 35 void __init sme_map_bootdata(char *real_mode_data); 36 void __init sme_unmap_bootdata(char *real_mode_data); 37 38 void __init sme_early_init(void); 39 40 void __init sme_encrypt_kernel(struct boot_params *bp); 41 void __init sme_enable(struct boot_params *bp); 42 43 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size); 44 int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size); 45 46 void __init mem_encrypt_free_decrypted_mem(void); 47 48 /* Architecture __weak replacement functions */ 49 void __init mem_encrypt_init(void); 50 51 bool sme_active(void); 52 bool sev_active(void); 53 54 #define __bss_decrypted __attribute__((__section__(".bss..decrypted"))) 55 56 #else /* !CONFIG_AMD_MEM_ENCRYPT */ 57 58 #define sme_me_mask 0ULL 59 60 static inline void __init sme_early_encrypt(resource_size_t paddr, 61 unsigned long size) { } 62 static inline void __init sme_early_decrypt(resource_size_t paddr, 63 unsigned long size) { } 64 65 static inline void __init sme_map_bootdata(char *real_mode_data) { } 66 static inline void __init sme_unmap_bootdata(char *real_mode_data) { } 67 68 static inline void __init sme_early_init(void) { } 69 70 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } 71 static inline void __init sme_enable(struct boot_params *bp) { } 72 73 static inline bool sme_active(void) { return false; } 74 static inline bool sev_active(void) { return false; } 75 76 static inline int __init 77 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } 78 static inline int __init 79 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; } 80 81 static inline void mem_encrypt_free_decrypted_mem(void) { } 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 static inline bool mem_encrypt_active(void) 99 { 100 return sme_me_mask; 101 } 102 103 static inline u64 sme_get_me_mask(void) 104 { 105 return sme_me_mask; 106 } 107 108 #endif /* __ASSEMBLY__ */ 109 110 #endif /* __X86_MEM_ENCRYPT_H__ */ 111