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/coco.h>
17
18#define GHCB_PROTOCOL_MIN 1ULL
19#define GHCB_PROTOCOL_MAX 2ULL
20#define GHCB_DEFAULT_USAGE 0ULL
21
22#define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); }
23
24struct boot_params;
25
26enum es_result {
27 ES_OK, /* All good */
28 ES_UNSUPPORTED, /* Requested operation not supported */
29 ES_VMM_ERROR, /* Unexpected state from the VMM */
30 ES_DECODE_FAILED, /* Instruction decoding failed */
31 ES_EXCEPTION, /* Instruction caused exception */
32 ES_RETRY, /* Retry instruction emulation */
33};
34
35struct es_fault_info {
36 unsigned long vector;
37 unsigned long error_code;
38 unsigned long cr2;
39};
40
41struct pt_regs;
42
43/* ES instruction emulation context */
44struct es_em_ctxt {
45 struct pt_regs *regs;
46 struct insn insn;
47 struct es_fault_info fi;
48};
49
50/*
51 * AMD SEV Confidential computing blob structure. The structure is
52 * defined in OVMF UEFI firmware header:
53 * https://github.com/tianocore/edk2/blob/master/OvmfPkg/Include/Guid/ConfidentialComputingSevSnpBlob.h
54 */
55#define CC_BLOB_SEV_HDR_MAGIC 0x45444d41
56struct cc_blob_sev_info {
57 u32 magic;
58 u16 version;
59 u16 reserved;
60 u64 secrets_phys;
61 u32 secrets_len;
62 u32 rsvd1;
63 u64 cpuid_phys;
64 u32 cpuid_len;
65 u32 rsvd2;
66} __packed;
67
68void do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code);
69
70static inline u64 lower_bits(u64 val, unsigned int bits)
71{
72 u64 mask = (1ULL << bits) - 1;
73
74 return (val & mask);
75}
76
77struct real_mode_header;
78enum stack_type;
79
80/* Early IDT entry points for #VC handler */
81extern void vc_no_ghcb(void);
82extern void vc_boot_ghcb(void);
83extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
84
85/* PVALIDATE return codes */
86#define PVALIDATE_FAIL_SIZEMISMATCH 6
87
88/* Software defined (when rFlags.CF = 1) */
89#define PVALIDATE_FAIL_NOUPDATE 255
90
91/* RMUPDATE detected 4K page and 2MB page overlap. */
92#define RMPUPDATE_FAIL_OVERLAP 4
93
94/* RMP page size */
95#define RMP_PG_SIZE_4K 0
96#define RMP_PG_SIZE_2M 1
97#define RMP_TO_PG_LEVEL(level) (((level) == RMP_PG_SIZE_4K) ? PG_LEVEL_4K : PG_LEVEL_2M)
98#define PG_LEVEL_TO_RMP(level) (((level) == PG_LEVEL_4K) ? RMP_PG_SIZE_4K : RMP_PG_SIZE_2M)
99
100struct rmp_state {
101 u64 gpa;
102 u8 assigned;
103 u8 pagesize;
104 u8 immutable;
105 u8 rsvd;
106 u32 asid;
107} __packed;
108
109#define RMPADJUST_VMSA_PAGE_BIT BIT(16)
110
111/* SNP Guest message request */
112struct snp_req_data {
113 unsigned long req_gpa;
114 unsigned long resp_gpa;
115 unsigned long data_gpa;
116 unsigned int data_npages;
117};
118
119struct sev_guest_platform_data {
120 u64 secrets_gpa;
121};
122
123/*
124 * The secrets page contains 96-bytes of reserved field that can be used by
125 * the guest OS. The guest OS uses the area to save the message sequence
126 * number for each VMPCK.
127 *
128 * See the GHCB spec section Secret page layout for the format for this area.
129 */
130struct secrets_os_area {
131 u32 msg_seqno_0;
132 u32 msg_seqno_1;
133 u32 msg_seqno_2;
134 u32 msg_seqno_3;
135 u64 ap_jump_table_pa;
136 u8 rsvd[40];
137 u8 guest_usage[32];
138} __packed;
139
140#define VMPCK_KEY_LEN 32
141
142/* See the SNP spec version 0.9 for secrets page format */
143struct snp_secrets_page_layout {
144 u32 version;
145 u32 imien : 1,
146 rsvd1 : 31;
147 u32 fms;
148 u32 rsvd2;
149 u8 gosvw[16];
150 u8 vmpck0[VMPCK_KEY_LEN];
151 u8 vmpck1[VMPCK_KEY_LEN];
152 u8 vmpck2[VMPCK_KEY_LEN];
153 u8 vmpck3[VMPCK_KEY_LEN];
154 struct secrets_os_area os_area;
155 u8 rsvd3[3840];
156} __packed;
157
158#ifdef CONFIG_AMD_MEM_ENCRYPT
159extern void __sev_es_ist_enter(struct pt_regs *regs);
160extern void __sev_es_ist_exit(void);
161static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
162{
163 if (cc_vendor == CC_VENDOR_AMD &&
164 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
165 __sev_es_ist_enter(regs);
166}
167static __always_inline void sev_es_ist_exit(void)
168{
169 if (cc_vendor == CC_VENDOR_AMD &&
170 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
171 __sev_es_ist_exit();
172}
173extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
174extern void __sev_es_nmi_complete(void);
175static __always_inline void sev_es_nmi_complete(void)
176{
177 if (cc_vendor == CC_VENDOR_AMD &&
178 cc_platform_has(attr: CC_ATTR_GUEST_STATE_ENCRYPT))
179 __sev_es_nmi_complete();
180}
181extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
182extern void sev_enable(struct boot_params *bp);
183
184static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs)
185{
186 int rc;
187
188 /* "rmpadjust" mnemonic support in binutils 2.36 and newer */
189 asm volatile(".byte 0xF3,0x0F,0x01,0xFE\n\t"
190 : "=a"(rc)
191 : "a"(vaddr), "c"(rmp_psize), "d"(attrs)
192 : "memory", "cc");
193
194 return rc;
195}
196static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate)
197{
198 bool no_rmpupdate;
199 int rc;
200
201 /* "pvalidate" mnemonic support in binutils 2.36 and newer */
202 asm volatile(".byte 0xF2, 0x0F, 0x01, 0xFF\n\t"
203 CC_SET(c)
204 : CC_OUT(c) (no_rmpupdate), "=a"(rc)
205 : "a"(vaddr), "c"(rmp_psize), "d"(validate)
206 : "memory", "cc");
207
208 if (no_rmpupdate)
209 return PVALIDATE_FAIL_NOUPDATE;
210
211 return rc;
212}
213
214struct snp_guest_request_ioctl;
215
216void setup_ghcb(void);
217void early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
218 unsigned long npages);
219void early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
220 unsigned long npages);
221void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
222void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
223void snp_set_wakeup_secondary_cpu(void);
224bool snp_init(struct boot_params *bp);
225void __noreturn snp_abort(void);
226void snp_dmi_setup(void);
227int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
228void snp_accept_memory(phys_addr_t start, phys_addr_t end);
229u64 snp_get_unsupported_features(u64 status);
230u64 sev_get_status(void);
231void sev_show_status(void);
232#else
233static inline void sev_es_ist_enter(struct pt_regs *regs) { }
234static inline void sev_es_ist_exit(void) { }
235static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; }
236static inline void sev_es_nmi_complete(void) { }
237static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
238static inline void sev_enable(struct boot_params *bp) { }
239static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) { return 0; }
240static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
241static inline void setup_ghcb(void) { }
242static inline void __init
243early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
244static inline void __init
245early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
246static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
247static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
248static inline void snp_set_wakeup_secondary_cpu(void) { }
249static inline bool snp_init(struct boot_params *bp) { return false; }
250static inline void snp_abort(void) { }
251static inline void snp_dmi_setup(void) { }
252static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio)
253{
254 return -ENOTTY;
255}
256
257static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
258static inline u64 snp_get_unsupported_features(u64 status) { return 0; }
259static inline u64 sev_get_status(void) { return 0; }
260static inline void sev_show_status(void) { }
261#endif
262
263#ifdef CONFIG_KVM_AMD_SEV
264bool snp_probe_rmptable_info(void);
265int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level);
266void snp_dump_hva_rmpentry(unsigned long address);
267int psmash(u64 pfn);
268int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid, bool immutable);
269int rmp_make_shared(u64 pfn, enum pg_level level);
270void snp_leak_pages(u64 pfn, unsigned int npages);
271void kdump_sev_callback(void);
272#else
273static inline bool snp_probe_rmptable_info(void) { return false; }
274static inline int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level) { return -ENODEV; }
275static inline void snp_dump_hva_rmpentry(unsigned long address) {}
276static inline int psmash(u64 pfn) { return -ENODEV; }
277static inline int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid,
278 bool immutable)
279{
280 return -ENODEV;
281}
282static inline int rmp_make_shared(u64 pfn, enum pg_level level) { return -ENODEV; }
283static inline void snp_leak_pages(u64 pfn, unsigned int npages) {}
284static inline void kdump_sev_callback(void) { }
285#endif
286
287#endif
288

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