xref: /openbmc/linux/arch/x86/include/asm/mem_encrypt.h (revision 18afb028)
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_X86_MEM_ENCRYPT
21 void __init mem_encrypt_init(void);
22 #else
23 static inline void mem_encrypt_init(void) { }
24 #endif
25 
26 #ifdef CONFIG_AMD_MEM_ENCRYPT
27 
28 extern u64 sme_me_mask;
29 extern u64 sev_status;
30 
31 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
32 			 unsigned long decrypted_kernel_vaddr,
33 			 unsigned long kernel_len,
34 			 unsigned long encryption_wa,
35 			 unsigned long encryption_pgd);
36 
37 void __init sme_early_encrypt(resource_size_t paddr,
38 			      unsigned long size);
39 void __init sme_early_decrypt(resource_size_t paddr,
40 			      unsigned long size);
41 
42 void __init sme_map_bootdata(char *real_mode_data);
43 void __init sme_unmap_bootdata(char *real_mode_data);
44 
45 void __init sme_early_init(void);
46 void __init sev_setup_arch(void);
47 
48 void __init sme_encrypt_kernel(struct boot_params *bp);
49 void __init sme_enable(struct boot_params *bp);
50 
51 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size);
52 int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
53 void __init early_set_mem_enc_dec_hypercall(unsigned long vaddr,
54 					    unsigned long size, bool enc);
55 
56 void __init mem_encrypt_free_decrypted_mem(void);
57 
58 void __init sev_es_init_vc_handling(void);
59 
60 #define __bss_decrypted __section(".bss..decrypted")
61 
62 #else	/* !CONFIG_AMD_MEM_ENCRYPT */
63 
64 #define sme_me_mask	0ULL
65 #define sev_status	0ULL
66 
67 static inline void __init sme_early_encrypt(resource_size_t paddr,
68 					    unsigned long size) { }
69 static inline void __init sme_early_decrypt(resource_size_t paddr,
70 					    unsigned long size) { }
71 
72 static inline void __init sme_map_bootdata(char *real_mode_data) { }
73 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
74 
75 static inline void __init sme_early_init(void) { }
76 static inline void __init sev_setup_arch(void) { }
77 
78 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
79 static inline void __init sme_enable(struct boot_params *bp) { }
80 
81 static inline void sev_es_init_vc_handling(void) { }
82 
83 static inline int __init
84 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
85 static inline int __init
86 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
87 static inline void __init
88 early_set_mem_enc_dec_hypercall(unsigned long vaddr, unsigned long size, bool enc) {}
89 
90 static inline void mem_encrypt_free_decrypted_mem(void) { }
91 
92 #define __bss_decrypted
93 
94 #endif	/* CONFIG_AMD_MEM_ENCRYPT */
95 
96 void add_encrypt_protection_map(void);
97 
98 /*
99  * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
100  * writing to or comparing values from the cr3 register.  Having the
101  * encryption mask set in cr3 enables the PGD entry to be encrypted and
102  * avoid special case handling of PGD allocations.
103  */
104 #define __sme_pa(x)		(__pa(x) | sme_me_mask)
105 #define __sme_pa_nodebug(x)	(__pa_nodebug(x) | sme_me_mask)
106 
107 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
108 
109 static inline u64 sme_get_me_mask(void)
110 {
111 	return sme_me_mask;
112 }
113 
114 #endif	/* __ASSEMBLY__ */
115 
116 #endif	/* __X86_MEM_ENCRYPT_H__ */
117