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
sme_early_encrypt(resource_size_t paddr,unsigned long size)62 static inline void __init sme_early_encrypt(resource_size_t paddr,
63 unsigned long size) { }
sme_early_decrypt(resource_size_t paddr,unsigned long size)64 static inline void __init sme_early_decrypt(resource_size_t paddr,
65 unsigned long size) { }
66
sme_map_bootdata(char * real_mode_data)67 static inline void __init sme_map_bootdata(char *real_mode_data) { }
sme_unmap_bootdata(char * real_mode_data)68 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
69
sme_early_init(void)70 static inline void __init sme_early_init(void) { }
71
sme_encrypt_kernel(struct boot_params * bp)72 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
sme_enable(struct boot_params * bp)73 static inline void __init sme_enable(struct boot_params *bp) { }
74
sme_active(void)75 static inline bool sme_active(void) { return false; }
sev_active(void)76 static inline bool sev_active(void) { return false; }
77
78 static inline int __init
early_set_memory_decrypted(unsigned long vaddr,unsigned long size)79 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
80 static inline int __init
early_set_memory_encrypted(unsigned long vaddr,unsigned long size)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
