1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * AMD Encrypted Register State Support
4 *
5 * Author: Joerg Roedel <jroedel@suse.de>
6 */
7
8 #ifndef __ASM_ENCRYPTED_STATE_H
9 #define __ASM_ENCRYPTED_STATE_H
10
11 #include <linux/types.h>
12 #include <linux/sev-guest.h>
13
14 #include <asm/insn.h>
15 #include <asm/sev-common.h>
16 #include <asm/bootparam.h>
17 #include <asm/coco.h>
18
19 #define GHCB_PROTOCOL_MIN 1ULL
20 #define GHCB_PROTOCOL_MAX 2ULL
21 #define GHCB_DEFAULT_USAGE 0ULL
22
23 #define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); }
24
25 enum es_result {
26 ES_OK, /* All good */
27 ES_UNSUPPORTED, /* Requested operation not supported */
28 ES_VMM_ERROR, /* Unexpected state from the VMM */
29 ES_DECODE_FAILED, /* Instruction decoding failed */
30 ES_EXCEPTION, /* Instruction caused exception */
31 ES_RETRY, /* Retry instruction emulation */
32 };
33
34 struct es_fault_info {
35 unsigned long vector;
36 unsigned long error_code;
37 unsigned long cr2;
38 };
39
40 struct pt_regs;
41
42 /* ES instruction emulation context */
43 struct es_em_ctxt {
44 struct pt_regs *regs;
45 struct insn insn;
46 struct es_fault_info fi;
47 };
48
49 /*
50 * AMD SEV Confidential computing blob structure. The structure is
51 * defined in OVMF UEFI firmware header:
52 * https://github.com/tianocore/edk2/blob/master/OvmfPkg/Include/Guid/ConfidentialComputingSevSnpBlob.h
53 */
54 #define CC_BLOB_SEV_HDR_MAGIC 0x45444d41
55 struct cc_blob_sev_info {
56 u32 magic;
57 u16 version;
58 u16 reserved;
59 u64 secrets_phys;
60 u32 secrets_len;
61 u32 rsvd1;
62 u64 cpuid_phys;
63 u32 cpuid_len;
64 u32 rsvd2;
65 } __packed;
66
67 void do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code);
68
lower_bits(u64 val,unsigned int bits)69 static inline u64 lower_bits(u64 val, unsigned int bits)
70 {
71 u64 mask = (1ULL << bits) - 1;
72
73 return (val & mask);
74 }
75
76 struct real_mode_header;
77 enum stack_type;
78
79 /* Early IDT entry points for #VC handler */
80 extern void vc_no_ghcb(void);
81 extern void vc_boot_ghcb(void);
82 extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
83
84 /* PVALIDATE return codes */
85 #define PVALIDATE_FAIL_SIZEMISMATCH 6
86
87 /* Software defined (when rFlags.CF = 1) */
88 #define PVALIDATE_FAIL_NOUPDATE 255
89
90 /* RMP page size */
91 #define RMP_PG_SIZE_4K 0
92 #define RMP_PG_SIZE_2M 1
93
94 #define RMPADJUST_VMSA_PAGE_BIT BIT(16)
95
96 /* SNP Guest message request */
97 struct snp_req_data {
98 unsigned long req_gpa;
99 unsigned long resp_gpa;
100 unsigned long data_gpa;
101 unsigned int data_npages;
102 };
103
104 struct sev_guest_platform_data {
105 u64 secrets_gpa;
106 };
107
108 /*
109 * The secrets page contains 96-bytes of reserved field that can be used by
110 * the guest OS. The guest OS uses the area to save the message sequence
111 * number for each VMPCK.
112 *
113 * See the GHCB spec section Secret page layout for the format for this area.
114 */
115 struct secrets_os_area {
116 u32 msg_seqno_0;
117 u32 msg_seqno_1;
118 u32 msg_seqno_2;
119 u32 msg_seqno_3;
120 u64 ap_jump_table_pa;
121 u8 rsvd[40];
122 u8 guest_usage[32];
123 } __packed;
124
125 #define VMPCK_KEY_LEN 32
126
127 /* See the SNP spec version 0.9 for secrets page format */
128 struct snp_secrets_page_layout {
129 u32 version;
130 u32 imien : 1,
131 rsvd1 : 31;
132 u32 fms;
133 u32 rsvd2;
134 u8 gosvw[16];
135 u8 vmpck0[VMPCK_KEY_LEN];
136 u8 vmpck1[VMPCK_KEY_LEN];
137 u8 vmpck2[VMPCK_KEY_LEN];
138 u8 vmpck3[VMPCK_KEY_LEN];
139 struct secrets_os_area os_area;
140 u8 rsvd3[3840];
141 } __packed;
142
143 #ifdef CONFIG_AMD_MEM_ENCRYPT
144 extern void __sev_es_ist_enter(struct pt_regs *regs);
145 extern void __sev_es_ist_exit(void);
sev_es_ist_enter(struct pt_regs * regs)146 static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
147 {
148 if (cc_vendor == CC_VENDOR_AMD &&
149 cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
150 __sev_es_ist_enter(regs);
151 }
sev_es_ist_exit(void)152 static __always_inline void sev_es_ist_exit(void)
153 {
154 if (cc_vendor == CC_VENDOR_AMD &&
155 cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
156 __sev_es_ist_exit();
157 }
158 extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
159 extern void __sev_es_nmi_complete(void);
sev_es_nmi_complete(void)160 static __always_inline void sev_es_nmi_complete(void)
161 {
162 if (cc_vendor == CC_VENDOR_AMD &&
163 cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
164 __sev_es_nmi_complete();
165 }
166 extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
167 extern void sev_enable(struct boot_params *bp);
168
rmpadjust(unsigned long vaddr,bool rmp_psize,unsigned long attrs)169 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs)
170 {
171 int rc;
172
173 /* "rmpadjust" mnemonic support in binutils 2.36 and newer */
174 asm volatile(".byte 0xF3,0x0F,0x01,0xFE\n\t"
175 : "=a"(rc)
176 : "a"(vaddr), "c"(rmp_psize), "d"(attrs)
177 : "memory", "cc");
178
179 return rc;
180 }
pvalidate(unsigned long vaddr,bool rmp_psize,bool validate)181 static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate)
182 {
183 bool no_rmpupdate;
184 int rc;
185
186 /* "pvalidate" mnemonic support in binutils 2.36 and newer */
187 asm volatile(".byte 0xF2, 0x0F, 0x01, 0xFF\n\t"
188 CC_SET(c)
189 : CC_OUT(c) (no_rmpupdate), "=a"(rc)
190 : "a"(vaddr), "c"(rmp_psize), "d"(validate)
191 : "memory", "cc");
192
193 if (no_rmpupdate)
194 return PVALIDATE_FAIL_NOUPDATE;
195
196 return rc;
197 }
198
199 struct snp_guest_request_ioctl;
200
201 void setup_ghcb(void);
202 void early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
203 unsigned long npages);
204 void early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
205 unsigned long npages);
206 void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
207 void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
208 void snp_set_wakeup_secondary_cpu(void);
209 bool snp_init(struct boot_params *bp);
210 void __noreturn snp_abort(void);
211 void snp_dmi_setup(void);
212 int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
213 void snp_accept_memory(phys_addr_t start, phys_addr_t end);
214 u64 snp_get_unsupported_features(u64 status);
215 u64 sev_get_status(void);
216 #else
sev_es_ist_enter(struct pt_regs * regs)217 static inline void sev_es_ist_enter(struct pt_regs *regs) { }
sev_es_ist_exit(void)218 static inline void sev_es_ist_exit(void) { }
sev_es_setup_ap_jump_table(struct real_mode_header * rmh)219 static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; }
sev_es_nmi_complete(void)220 static inline void sev_es_nmi_complete(void) { }
sev_es_efi_map_ghcbs(pgd_t * pgd)221 static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
sev_enable(struct boot_params * bp)222 static inline void sev_enable(struct boot_params *bp) { }
pvalidate(unsigned long vaddr,bool rmp_psize,bool validate)223 static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) { return 0; }
rmpadjust(unsigned long vaddr,bool rmp_psize,unsigned long attrs)224 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
setup_ghcb(void)225 static inline void setup_ghcb(void) { }
226 static inline void __init
early_snp_set_memory_private(unsigned long vaddr,unsigned long paddr,unsigned long npages)227 early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
228 static inline void __init
early_snp_set_memory_shared(unsigned long vaddr,unsigned long paddr,unsigned long npages)229 early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
snp_set_memory_shared(unsigned long vaddr,unsigned long npages)230 static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
snp_set_memory_private(unsigned long vaddr,unsigned long npages)231 static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
snp_set_wakeup_secondary_cpu(void)232 static inline void snp_set_wakeup_secondary_cpu(void) { }
snp_init(struct boot_params * bp)233 static inline bool snp_init(struct boot_params *bp) { return false; }
snp_abort(void)234 static inline void snp_abort(void) { }
snp_dmi_setup(void)235 static inline void snp_dmi_setup(void) { }
snp_issue_guest_request(u64 exit_code,struct snp_req_data * input,struct snp_guest_request_ioctl * rio)236 static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio)
237 {
238 return -ENOTTY;
239 }
240
snp_accept_memory(phys_addr_t start,phys_addr_t end)241 static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
snp_get_unsupported_features(u64 status)242 static inline u64 snp_get_unsupported_features(u64 status) { return 0; }
sev_get_status(void)243 static inline u64 sev_get_status(void) { return 0; }
244 #endif
245
246 #endif
247