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 #include <linux/cc_platform.h>
17
18 #include <asm/bootparam.h>
19
20 #ifdef CONFIG_AMD_MEM_ENCRYPT
21
22 extern u64 sme_me_mask;
23 extern u64 sev_status;
24 extern bool sev_enabled;
25
26 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
27 unsigned long decrypted_kernel_vaddr,
28 unsigned long kernel_len,
29 unsigned long encryption_wa,
30 unsigned long encryption_pgd);
31
32 void __init sme_early_encrypt(resource_size_t paddr,
33 unsigned long size);
34 void __init sme_early_decrypt(resource_size_t paddr,
35 unsigned long size);
36
37 void __init sme_map_bootdata(char *real_mode_data);
38 void __init sme_unmap_bootdata(char *real_mode_data);
39
40 void __init sme_early_init(void);
41
42 void __init sme_encrypt_kernel(struct boot_params *bp);
43 void __init sme_enable(struct boot_params *bp);
44
45 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size);
46 int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
47
48 void __init mem_encrypt_free_decrypted_mem(void);
49
50 void __init sev_es_init_vc_handling(void);
51 bool sme_active(void);
52 bool sev_active(void);
53 bool sev_es_active(void);
54
55 void __init mem_encrypt_init(void);
56
57 #define __bss_decrypted __section(".bss..decrypted")
58
59 #else /* !CONFIG_AMD_MEM_ENCRYPT */
60
61 #define sme_me_mask 0ULL
62
sme_early_encrypt(resource_size_t paddr,unsigned long size)63 static inline void __init sme_early_encrypt(resource_size_t paddr,
64 unsigned long size) { }
sme_early_decrypt(resource_size_t paddr,unsigned long size)65 static inline void __init sme_early_decrypt(resource_size_t paddr,
66 unsigned long size) { }
67
sme_map_bootdata(char * real_mode_data)68 static inline void __init sme_map_bootdata(char *real_mode_data) { }
sme_unmap_bootdata(char * real_mode_data)69 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
70
sme_early_init(void)71 static inline void __init sme_early_init(void) { }
72
sme_encrypt_kernel(struct boot_params * bp)73 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
sme_enable(struct boot_params * bp)74 static inline void __init sme_enable(struct boot_params *bp) { }
75
sev_es_init_vc_handling(void)76 static inline void sev_es_init_vc_handling(void) { }
sme_active(void)77 static inline bool sme_active(void) { return false; }
sev_active(void)78 static inline bool sev_active(void) { return false; }
sev_es_active(void)79 static inline bool sev_es_active(void) { return false; }
80
81 static inline int __init
early_set_memory_decrypted(unsigned long vaddr,unsigned long size)82 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
83 static inline int __init
early_set_memory_encrypted(unsigned long vaddr,unsigned long size)84 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
85
mem_encrypt_free_decrypted_mem(void)86 static inline void mem_encrypt_free_decrypted_mem(void) { }
87
mem_encrypt_init(void)88 static inline void mem_encrypt_init(void) { }
89
90 #define __bss_decrypted
91
92 #endif /* CONFIG_AMD_MEM_ENCRYPT */
93
94 /*
95 * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
96 * writing to or comparing values from the cr3 register. Having the
97 * encryption mask set in cr3 enables the PGD entry to be encrypted and
98 * avoid special case handling of PGD allocations.
99 */
100 #define __sme_pa(x) (__pa(x) | sme_me_mask)
101 #define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask)
102
103 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
104
mem_encrypt_active(void)105 static inline bool mem_encrypt_active(void)
106 {
107 return sme_me_mask;
108 }
109
sme_get_me_mask(void)110 static inline u64 sme_get_me_mask(void)
111 {
112 return sme_me_mask;
113 }
114
115 #endif /* __ASSEMBLY__ */
116
117 #endif /* __X86_MEM_ENCRYPT_H__ */
118