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
25enum 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
34struct es_fault_info {
35 unsigned long vector;
36 unsigned long error_code;
37 unsigned long cr2;
38};
39
40struct pt_regs;
41
42/* ES instruction emulation context */
43struct 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
55struct 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
67void do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code);
68
69static inline u64 lower_bits(u64 val, unsigned int bits)
70{
71 u64 mask = (1ULL << bits) - 1;
72
73 return (val & mask);
74}
75
76struct real_mode_header;
77enum stack_type;
78
79/* Early IDT entry points for #VC handler */
80extern void vc_no_ghcb(void);
81extern void vc_boot_ghcb(void);
82extern 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 */
97struct 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
104struct 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 */
115struct 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 */
128struct 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
144extern void __sev_es_ist_enter(struct pt_regs *regs);
145extern void __sev_es_ist_exit(void);
146static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
147{
148 if (cc_vendor == CC_VENDOR_AMD &&
149 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
150 __sev_es_ist_enter(regs);
151}
152static __always_inline void sev_es_ist_exit(void)
153{
154 if (cc_vendor == CC_VENDOR_AMD &&
155 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
156 __sev_es_ist_exit();
157}
158extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
159extern void __sev_es_nmi_complete(void);
160static __always_inline void sev_es_nmi_complete(void)
161{
162 if (cc_vendor == CC_VENDOR_AMD &&
163 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
164 __sev_es_nmi_complete();
165}
166extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
167extern void sev_enable(struct boot_params *bp);
168
169static 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}
181static 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
199struct snp_guest_request_ioctl;
200
201void setup_ghcb(void);
202void __init early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
203 unsigned long npages);
204void __init early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
205 unsigned long npages);
206void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op);
207void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
208void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
209void snp_set_wakeup_secondary_cpu(void);
210bool snp_init(struct boot_params *bp);
211void __init __noreturn snp_abort(void);
212int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
213void snp_accept_memory(phys_addr_t start, phys_addr_t end);
214u64 snp_get_unsupported_features(u64 status);
215u64 sev_get_status(void);
216#else
217static inline void sev_es_ist_enter(struct pt_regs *regs) { }
218static inline void sev_es_ist_exit(void) { }
219static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; }
220static inline void sev_es_nmi_complete(void) { }
221static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
222static inline void sev_enable(struct boot_params *bp) { }
223static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) { return 0; }
224static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
225static inline void setup_ghcb(void) { }
226static inline void __init
227early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
228static inline void __init
229early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
230static inline void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op) { }
231static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
232static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
233static inline void snp_set_wakeup_secondary_cpu(void) { }
234static inline bool snp_init(struct boot_params *bp) { return false; }
235static inline void snp_abort(void) { }
236static 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
241static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
242static inline u64 snp_get_unsupported_features(u64 status) { return 0; }
243static inline u64 sev_get_status(void) { return 0; }
244#endif
245
246#endif
247

source code of linux/arch/x86/include/asm/sev.h