arch/x86/include/asm/sev.h

   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
  24 struct boot_params;
  25
  26 enum 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
  35 struct es_fault_info {
  36         unsigned long vector;
  37         unsigned long error_code;
  38         unsigned long cr2;
  39 };
  40
  41 struct pt_regs;
  42
  43 /* ES instruction emulation context */
  44 struct 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
  56 struct 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
  68 void do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code);
  69
  70 static inline u64 lower_bits(u64 val, unsigned int bits)
  71 {
  72         u64 mask = (1ULL << bits) - 1;
  73
  74         return (val & mask);
  75 }
  76
  77 struct real_mode_header;
  78 enum stack_type;
  79
  80 /* Early IDT entry points for #VC handler */
  81 extern void vc_no_ghcb(void);
  82 extern void vc_boot_ghcb(void);
  83 extern 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
 100 struct 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 */
 112 struct 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
 119 struct 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  */
 130 struct 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 */
 143 struct 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
 159 extern void __sev_es_ist_enter(struct pt_regs *regs);
 160 extern void __sev_es_ist_exit(void);
 161 static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
 162 {
 163         if (cc_vendor == CC_VENDOR_AMD &&
 164             cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 165                 __sev_es_ist_enter(regs);
 166 }
 167 static __always_inline void sev_es_ist_exit(void)
 168 {
 169         if (cc_vendor == CC_VENDOR_AMD &&
 170             cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 171                 __sev_es_ist_exit();
 172 }
 173 extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
 174 extern void __sev_es_nmi_complete(void);
 175 static __always_inline void sev_es_nmi_complete(void)
 176 {
 177         if (cc_vendor == CC_VENDOR_AMD &&
 178             cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 179                 __sev_es_nmi_complete();
 180 }
 181 extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
 182 extern void sev_enable(struct boot_params *bp);
 183
 184 static 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 }
 196 static 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
 214 struct snp_guest_request_ioctl;
 215
 216 void setup_ghcb(void);
 217 void early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
 218                                   unsigned long npages);
 219 void early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
 220                                  unsigned long npages);
 221 void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op);
 222 void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
 223 void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
 224 void snp_set_wakeup_secondary_cpu(void);
 225 bool snp_init(struct boot_params *bp);
 226 void __noreturn snp_abort(void);
 227 int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
 228 void snp_accept_memory(phys_addr_t start, phys_addr_t end);
 229 u64 snp_get_unsupported_features(u64 status);
 230 u64 sev_get_status(void);
 231 void kdump_sev_callback(void);
 232 void sev_show_status(void);
 233 #else
 234 static inline void sev_es_ist_enter(struct pt_regs *regs) { }
 235 static inline void sev_es_ist_exit(void) { }
 236 static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; }
 237 static inline void sev_es_nmi_complete(void) { }
 238 static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
 239 static inline void sev_enable(struct boot_params *bp) { }
 240 static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) { return 0; }
 241 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
 242 static inline void setup_ghcb(void) { }
 243 static inline void __init
 244 early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
 245 static inline void __init
 246 early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
 247 static inline void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op) { }
 248 static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
 249 static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
 250 static inline void snp_set_wakeup_secondary_cpu(void) { }
 251 static inline bool snp_init(struct boot_params *bp) { return false; }
 252 static inline void snp_abort(void) { }
 253 static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio)
 254 {
 255         return -ENOTTY;
 256 }
 257
 258 static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
 259 static inline u64 snp_get_unsupported_features(u64 status) { return 0; }
 260 static inline u64 sev_get_status(void) { return 0; }
 261 static inline void kdump_sev_callback(void) { }
 262 static inline void sev_show_status(void) { }
 263 #endif
 264
 265 #ifdef CONFIG_KVM_AMD_SEV
 266 bool snp_probe_rmptable_info(void);
 267 int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level);
 268 void snp_dump_hva_rmpentry(unsigned long address);
 269 int psmash(u64 pfn);
 270 int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid, bool immutable);
 271 int rmp_make_shared(u64 pfn, enum pg_level level);
 272 void snp_leak_pages(u64 pfn, unsigned int npages);
 273 #else
 274 static inline bool snp_probe_rmptable_info(void) { return false; }
 275 static inline int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level) { return -ENODEV; }
 276 static inline void snp_dump_hva_rmpentry(unsigned long address) {}
 277 static inline int psmash(u64 pfn) { return -ENODEV; }
 278 static inline int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid,
 279                                    bool immutable)
 280 {
 281         return -ENODEV;
 282 }
 283 static inline int rmp_make_shared(u64 pfn, enum pg_level level) { return -ENODEV; }
 284 static inline void snp_leak_pages(u64 pfn, unsigned int npages) {}
 285 #endif
 286
 287 #endif