xref: /openbmc/linux/arch/x86/include/asm/mem_encrypt.h (revision c34a8052)
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/asm.h>
19 struct boot_params;
20 
21 #ifdef CONFIG_X86_MEM_ENCRYPT
22 void __init mem_encrypt_init(void);
23 #else
24 static inline void mem_encrypt_init(void) { }
25 #endif
26 
27 #ifdef CONFIG_AMD_MEM_ENCRYPT
28 
29 extern u64 sme_me_mask;
30 extern u64 sev_status;
31 
32 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
33 			 unsigned long decrypted_kernel_vaddr,
34 			 unsigned long kernel_len,
35 			 unsigned long encryption_wa,
36 			 unsigned long encryption_pgd);
37 
38 void __init sme_early_encrypt(resource_size_t paddr,
39 			      unsigned long size);
40 void __init sme_early_decrypt(resource_size_t paddr,
41 			      unsigned long size);
42 
43 void __init sme_map_bootdata(char *real_mode_data);
44 void __init sme_unmap_bootdata(char *real_mode_data);
45 
46 void __init sme_early_init(void);
47 void __init sev_setup_arch(void);
48 
49 void sme_encrypt_kernel(struct boot_params *bp);
50 void sme_enable(struct boot_params *bp);
51 
52 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size);
53 int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
54 void __init early_set_mem_enc_dec_hypercall(unsigned long vaddr,
55 					    unsigned long size, bool enc);
56 
57 void __init mem_encrypt_free_decrypted_mem(void);
58 
59 void __init sev_es_init_vc_handling(void);
60 
61 static inline u64 sme_get_me_mask(void)
62 {
63 	return RIP_REL_REF(sme_me_mask);
64 }
65 
66 #define __bss_decrypted __section(".bss..decrypted")
67 
68 #else	/* !CONFIG_AMD_MEM_ENCRYPT */
69 
70 #define sme_me_mask	0ULL
71 #define sev_status	0ULL
72 
73 static inline void __init sme_early_encrypt(resource_size_t paddr,
74 					    unsigned long size) { }
75 static inline void __init sme_early_decrypt(resource_size_t paddr,
76 					    unsigned long size) { }
77 
78 static inline void __init sme_map_bootdata(char *real_mode_data) { }
79 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
80 
81 static inline void __init sme_early_init(void) { }
82 static inline void __init sev_setup_arch(void) { }
83 
84 static inline void sme_encrypt_kernel(struct boot_params *bp) { }
85 static inline void sme_enable(struct boot_params *bp) { }
86 
87 static inline void sev_es_init_vc_handling(void) { }
88 
89 static inline int __init
90 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
91 static inline int __init
92 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
93 static inline void __init
94 early_set_mem_enc_dec_hypercall(unsigned long vaddr, unsigned long size, bool enc) {}
95 
96 static inline void mem_encrypt_free_decrypted_mem(void) { }
97 
98 static inline u64 sme_get_me_mask(void) { return 0; }
99 
100 #define __bss_decrypted
101 
102 #endif	/* CONFIG_AMD_MEM_ENCRYPT */
103 
104 void add_encrypt_protection_map(void);
105 
106 /*
107  * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
108  * writing to or comparing values from the cr3 register.  Having the
109  * encryption mask set in cr3 enables the PGD entry to be encrypted and
110  * avoid special case handling of PGD allocations.
111  */
112 #define __sme_pa(x)		(__pa(x) | sme_me_mask)
113 #define __sme_pa_nodebug(x)	(__pa_nodebug(x) | sme_me_mask)
114 
115 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
116 
117 #endif	/* __ASSEMBLY__ */
118 
119 #endif	/* __X86_MEM_ENCRYPT_H__ */
120