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
sme_early_encrypt(resource_size_t paddr,unsigned long size)59 static inline void __init sme_early_encrypt(resource_size_t paddr,
60 unsigned long size) { }
sme_early_decrypt(resource_size_t paddr,unsigned long size)61 static inline void __init sme_early_decrypt(resource_size_t paddr,
62 unsigned long size) { }
63
sme_map_bootdata(char * real_mode_data)64 static inline void __init sme_map_bootdata(char *real_mode_data) { }
sme_unmap_bootdata(char * real_mode_data)65 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
66
sme_early_init(void)67 static inline void __init sme_early_init(void) { }
68
sme_encrypt_kernel(struct boot_params * bp)69 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
sme_enable(struct boot_params * bp)70 static inline void __init sme_enable(struct boot_params *bp) { }
71
sme_active(void)72 static inline bool sme_active(void) { return false; }
sev_active(void)73 static inline bool sev_active(void) { return false; }
74
75 static inline int __init
early_set_memory_decrypted(unsigned long vaddr,unsigned long size)76 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
77 static inline int __init
early_set_memory_encrypted(unsigned long vaddr,unsigned long size)78 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
79
mem_encrypt_init(void)80 static inline void mem_encrypt_init(void) { }
81
82 #define __bss_decrypted
83
84 #endif /* CONFIG_AMD_MEM_ENCRYPT */
85
86 /*
87 * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
88 * writing to or comparing values from the cr3 register. Having the
89 * encryption mask set in cr3 enables the PGD entry to be encrypted and
90 * avoid special case handling of PGD allocations.
91 */
92 #define __sme_pa(x) (__pa(x) | sme_me_mask)
93 #define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask)
94
95 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
96
mem_encrypt_active(void)97 static inline bool mem_encrypt_active(void)
98 {
99 return sme_me_mask;
100 }
101
sme_get_me_mask(void)102 static inline u64 sme_get_me_mask(void)
103 {
104 return sme_me_mask;
105 }
106
107 #endif /* __ASSEMBLY__ */
108
109 #endif /* __X86_MEM_ENCRYPT_H__ */
110