xref: /openbmc/linux/arch/x86/include/asm/mem_encrypt.h (revision 5e0266f0)
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 
25 void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
26 			 unsigned long decrypted_kernel_vaddr,
27 			 unsigned long kernel_len,
28 			 unsigned long encryption_wa,
29 			 unsigned long encryption_pgd);
30 
31 void __init sme_early_encrypt(resource_size_t paddr,
32 			      unsigned long size);
33 void __init sme_early_decrypt(resource_size_t paddr,
34 			      unsigned long size);
35 
36 void __init sme_map_bootdata(char *real_mode_data);
37 void __init sme_unmap_bootdata(char *real_mode_data);
38 
39 void __init sme_early_init(void);
40 void __init sev_setup_arch(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 void __init early_set_mem_enc_dec_hypercall(unsigned long vaddr, int npages,
48 					    bool enc);
49 
50 void __init mem_encrypt_free_decrypted_mem(void);
51 
52 void __init sev_es_init_vc_handling(void);
53 
54 #define __bss_decrypted __section(".bss..decrypted")
55 
56 #else	/* !CONFIG_AMD_MEM_ENCRYPT */
57 
58 #define sme_me_mask	0ULL
59 
60 static inline void __init sme_early_encrypt(resource_size_t paddr,
61 					    unsigned long size) { }
62 static inline void __init sme_early_decrypt(resource_size_t paddr,
63 					    unsigned long size) { }
64 
65 static inline void __init sme_map_bootdata(char *real_mode_data) { }
66 static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
67 
68 static inline void __init sme_early_init(void) { }
69 static inline void __init sev_setup_arch(void) { }
70 
71 static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
72 static inline void __init sme_enable(struct boot_params *bp) { }
73 
74 static inline void sev_es_init_vc_handling(void) { }
75 
76 static inline int __init
77 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
78 static inline int __init
79 early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
80 static inline void __init
81 early_set_mem_enc_dec_hypercall(unsigned long vaddr, int npages, bool enc) {}
82 
83 static inline void mem_encrypt_free_decrypted_mem(void) { }
84 
85 #define __bss_decrypted
86 
87 #endif	/* CONFIG_AMD_MEM_ENCRYPT */
88 
89 /* Architecture __weak replacement functions */
90 void __init mem_encrypt_init(void);
91 
92 void add_encrypt_protection_map(void);
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 
105 static inline u64 sme_get_me_mask(void)
106 {
107 	return sme_me_mask;
108 }
109 
110 #endif	/* __ASSEMBLY__ */
111 
112 #endif	/* __X86_MEM_ENCRYPT_H__ */
113