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 /* Architecture __weak replacement functions */ 47 void __init mem_encrypt_init(void); 48 void __init mem_encrypt_free_decrypted_mem(void); 49 50 bool sme_active(void); 51 bool sev_active(void); 52 53 #define __bss_decrypted __attribute__((__section__(".bss..decrypted"))) 54 55 #else /* !CONFIG_AMD_MEM_ENCRYPT */ 56 57 #define sme_me_mask 0ULL 58 59 static inline void __init sme_early_encrypt(resource_size_t paddr, 60 unsigned long size) { } 61 static inline void __init sme_early_decrypt(resource_size_t paddr, 62 unsigned long size) { } 63 64 static inline void __init sme_map_bootdata(char *real_mode_data) { } 65 static inline void __init sme_unmap_bootdata(char *real_mode_data) { } 66 67 static inline void __init sme_early_init(void) { } 68 69 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } 70 static inline void __init sme_enable(struct boot_params *bp) { } 71 72 static inline bool sme_active(void) { return false; } 73 static inline bool sev_active(void) { return false; } 74 75 static inline int __init 76 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } 77 static inline int __init 78 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; } 79 80 #define __bss_decrypted 81 82 #endif /* CONFIG_AMD_MEM_ENCRYPT */ 83 84 /* 85 * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when 86 * writing to or comparing values from the cr3 register. Having the 87 * encryption mask set in cr3 enables the PGD entry to be encrypted and 88 * avoid special case handling of PGD allocations. 89 */ 90 #define __sme_pa(x) (__pa(x) | sme_me_mask) 91 #define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask) 92 93 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[]; 94 95 static inline bool mem_encrypt_active(void) 96 { 97 return sme_me_mask; 98 } 99 100 static inline u64 sme_get_me_mask(void) 101 { 102 return sme_me_mask; 103 } 104 105 #endif /* __ASSEMBLY__ */ 106 107 #endif /* __X86_MEM_ENCRYPT_H__ */ 108