1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_EFI_H 3 #define _ASM_X86_EFI_H 4 5 #include <asm/fpu/api.h> 6 #include <asm/processor-flags.h> 7 #include <asm/tlb.h> 8 #include <asm/nospec-branch.h> 9 #include <asm/mmu_context.h> 10 #include <asm/ibt.h> 11 #include <linux/build_bug.h> 12 #include <linux/kernel.h> 13 #include <linux/pgtable.h> 14 15 extern unsigned long efi_fw_vendor, efi_config_table; 16 extern unsigned long efi_mixed_mode_stack_pa; 17 18 /* 19 * We map the EFI regions needed for runtime services non-contiguously, 20 * with preserved alignment on virtual addresses starting from -4G down 21 * for a total max space of 64G. This way, we provide for stable runtime 22 * services addresses across kernels so that a kexec'd kernel can still 23 * use them. 24 * 25 * This is the main reason why we're doing stable VA mappings for RT 26 * services. 27 */ 28 29 #define EFI32_LOADER_SIGNATURE "EL32" 30 #define EFI64_LOADER_SIGNATURE "EL64" 31 32 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF 33 34 #define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE 35 36 /* 37 * The EFI services are called through variadic functions in many cases. These 38 * functions are implemented in assembler and support only a fixed number of 39 * arguments. The macros below allows us to check at build time that we don't 40 * try to call them with too many arguments. 41 * 42 * __efi_nargs() will return the number of arguments if it is 7 or less, and 43 * cause a BUILD_BUG otherwise. The limitations of the C preprocessor make it 44 * impossible to calculate the exact number of arguments beyond some 45 * pre-defined limit. The maximum number of arguments currently supported by 46 * any of the thunks is 7, so this is good enough for now and can be extended 47 * in the obvious way if we ever need more. 48 */ 49 50 #define __efi_nargs(...) __efi_nargs_(__VA_ARGS__) 51 #define __efi_nargs_(...) __efi_nargs__(0, ##__VA_ARGS__, \ 52 __efi_arg_sentinel(9), __efi_arg_sentinel(8), \ 53 __efi_arg_sentinel(7), __efi_arg_sentinel(6), \ 54 __efi_arg_sentinel(5), __efi_arg_sentinel(4), \ 55 __efi_arg_sentinel(3), __efi_arg_sentinel(2), \ 56 __efi_arg_sentinel(1), __efi_arg_sentinel(0)) 57 #define __efi_nargs__(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, ...) \ 58 __take_second_arg(n, \ 59 ({ BUILD_BUG_ON_MSG(1, "__efi_nargs limit exceeded"); 10; })) 60 #define __efi_arg_sentinel(n) , n 61 62 /* 63 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis 64 * represents more than n arguments. 65 */ 66 67 #define __efi_nargs_check(f, n, ...) \ 68 __efi_nargs_check_(f, __efi_nargs(__VA_ARGS__), n) 69 #define __efi_nargs_check_(f, p, n) __efi_nargs_check__(f, p, n) 70 #define __efi_nargs_check__(f, p, n) ({ \ 71 BUILD_BUG_ON_MSG( \ 72 (p) > (n), \ 73 #f " called with too many arguments (" #p ">" #n ")"); \ 74 }) 75 76 static inline void efi_fpu_begin(void) 77 { 78 /* 79 * The UEFI calling convention (UEFI spec 2.3.2 and 2.3.4) requires 80 * that FCW and MXCSR (64-bit) must be initialized prior to calling 81 * UEFI code. (Oddly the spec does not require that the FPU stack 82 * be empty.) 83 */ 84 kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR); 85 } 86 87 static inline void efi_fpu_end(void) 88 { 89 kernel_fpu_end(); 90 } 91 92 #ifdef CONFIG_X86_32 93 #define EFI_X86_KERNEL_ALLOC_LIMIT (SZ_512M - 1) 94 95 #define arch_efi_call_virt_setup() \ 96 ({ \ 97 efi_fpu_begin(); \ 98 firmware_restrict_branch_speculation_start(); \ 99 }) 100 101 #define arch_efi_call_virt_teardown() \ 102 ({ \ 103 firmware_restrict_branch_speculation_end(); \ 104 efi_fpu_end(); \ 105 }) 106 107 #else /* !CONFIG_X86_32 */ 108 #define EFI_X86_KERNEL_ALLOC_LIMIT EFI_ALLOC_LIMIT 109 110 extern asmlinkage u64 __efi_call(void *fp, ...); 111 112 extern bool efi_disable_ibt_for_runtime; 113 114 #define efi_call(...) ({ \ 115 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \ 116 __efi_call(__VA_ARGS__); \ 117 }) 118 119 #define arch_efi_call_virt_setup() \ 120 ({ \ 121 efi_sync_low_kernel_mappings(); \ 122 efi_fpu_begin(); \ 123 firmware_restrict_branch_speculation_start(); \ 124 efi_enter_mm(); \ 125 }) 126 127 #undef arch_efi_call_virt 128 #define arch_efi_call_virt(p, f, args...) ({ \ 129 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \ 130 ret = efi_call((void *)p->f, args); \ 131 ibt_restore(ibt); \ 132 ret; \ 133 }) 134 135 #define arch_efi_call_virt_teardown() \ 136 ({ \ 137 efi_leave_mm(); \ 138 firmware_restrict_branch_speculation_end(); \ 139 efi_fpu_end(); \ 140 }) 141 142 #ifdef CONFIG_KASAN 143 /* 144 * CONFIG_KASAN may redefine memset to __memset. __memset function is present 145 * only in kernel binary. Since the EFI stub linked into a separate binary it 146 * doesn't have __memset(). So we should use standard memset from 147 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove. 148 */ 149 #undef memcpy 150 #undef memset 151 #undef memmove 152 #endif 153 154 #endif /* CONFIG_X86_32 */ 155 156 extern int __init efi_memblock_x86_reserve_range(void); 157 extern void __init efi_print_memmap(void); 158 extern void __init efi_map_region(efi_memory_desc_t *md); 159 extern void __init efi_map_region_fixed(efi_memory_desc_t *md); 160 extern void efi_sync_low_kernel_mappings(void); 161 extern int __init efi_alloc_page_tables(void); 162 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); 163 extern void __init efi_runtime_update_mappings(void); 164 extern void __init efi_dump_pagetable(void); 165 extern void __init efi_apply_memmap_quirks(void); 166 extern int __init efi_reuse_config(u64 tables, int nr_tables); 167 extern void efi_delete_dummy_variable(void); 168 extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr); 169 extern void efi_free_boot_services(void); 170 171 void efi_enter_mm(void); 172 void efi_leave_mm(void); 173 174 /* kexec external ABI */ 175 struct efi_setup_data { 176 u64 fw_vendor; 177 u64 __unused; 178 u64 tables; 179 u64 smbios; 180 u64 reserved[8]; 181 }; 182 183 extern u64 efi_setup; 184 185 #ifdef CONFIG_EFI 186 extern u64 __efi64_thunk(u32, ...); 187 188 #define efi64_thunk(...) ({ \ 189 u64 __pad[3]; /* must have space for 3 args on the stack */ \ 190 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \ 191 __efi64_thunk(__VA_ARGS__, __pad); \ 192 }) 193 194 static inline bool efi_is_mixed(void) 195 { 196 if (!IS_ENABLED(CONFIG_EFI_MIXED)) 197 return false; 198 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT); 199 } 200 201 static inline bool efi_runtime_supported(void) 202 { 203 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT)) 204 return true; 205 206 return IS_ENABLED(CONFIG_EFI_MIXED); 207 } 208 209 extern void parse_efi_setup(u64 phys_addr, u32 data_len); 210 211 extern void efi_thunk_runtime_setup(void); 212 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size, 213 unsigned long descriptor_size, 214 u32 descriptor_version, 215 efi_memory_desc_t *virtual_map, 216 unsigned long systab_phys); 217 218 /* arch specific definitions used by the stub code */ 219 220 #ifdef CONFIG_EFI_MIXED 221 222 #define EFI_ALLOC_LIMIT (efi_is_64bit() ? ULONG_MAX : U32_MAX) 223 224 #define ARCH_HAS_EFISTUB_WRAPPERS 225 226 static inline bool efi_is_64bit(void) 227 { 228 extern const bool efi_is64; 229 230 return efi_is64; 231 } 232 233 static inline bool efi_is_native(void) 234 { 235 return efi_is_64bit(); 236 } 237 238 #define efi_table_attr(inst, attr) \ 239 (efi_is_native() ? (inst)->attr \ 240 : efi_mixed_table_attr((inst), attr)) 241 242 #define efi_mixed_table_attr(inst, attr) \ 243 (__typeof__(inst->attr)) \ 244 _Generic(inst->mixed_mode.attr, \ 245 u32: (unsigned long)(inst->mixed_mode.attr), \ 246 default: (inst->mixed_mode.attr)) 247 248 /* 249 * The following macros allow translating arguments if necessary from native to 250 * mixed mode. The use case for this is to initialize the upper 32 bits of 251 * output parameters, and where the 32-bit method requires a 64-bit argument, 252 * which must be split up into two arguments to be thunked properly. 253 * 254 * As examples, the AllocatePool boot service returns the address of the 255 * allocation, but it will not set the high 32 bits of the address. To ensure 256 * that the full 64-bit address is initialized, we zero-init the address before 257 * calling the thunk. 258 * 259 * The FreePages boot service takes a 64-bit physical address even in 32-bit 260 * mode. For the thunk to work correctly, a native 64-bit call of 261 * free_pages(addr, size) 262 * must be translated to 263 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size) 264 * so that the two 32-bit halves of addr get pushed onto the stack separately. 265 */ 266 267 static inline void *efi64_zero_upper(void *p) 268 { 269 ((u32 *)p)[1] = 0; 270 return p; 271 } 272 273 static inline u32 efi64_convert_status(efi_status_t status) 274 { 275 return (u32)(status | (u64)status >> 32); 276 } 277 278 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32 279 280 #define __efi64_argmap_free_pages(addr, size) \ 281 ((addr), 0, (size)) 282 283 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \ 284 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver)) 285 286 #define __efi64_argmap_allocate_pool(type, size, buffer) \ 287 ((type), (size), efi64_zero_upper(buffer)) 288 289 #define __efi64_argmap_create_event(type, tpl, f, c, event) \ 290 ((type), (tpl), (f), (c), efi64_zero_upper(event)) 291 292 #define __efi64_argmap_set_timer(event, type, time) \ 293 ((event), (type), lower_32_bits(time), upper_32_bits(time)) 294 295 #define __efi64_argmap_wait_for_event(num, event, index) \ 296 ((num), (event), efi64_zero_upper(index)) 297 298 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \ 299 ((handle), (protocol), efi64_zero_upper(interface)) 300 301 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \ 302 ((protocol), (reg), efi64_zero_upper(interface)) 303 304 #define __efi64_argmap_locate_device_path(protocol, path, handle) \ 305 ((protocol), (path), efi64_zero_upper(handle)) 306 307 #define __efi64_argmap_exit(handle, status, size, data) \ 308 ((handle), efi64_convert_status(status), (size), (data)) 309 310 /* PCI I/O */ 311 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \ 312 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \ 313 efi64_zero_upper(dev), efi64_zero_upper(func)) 314 315 /* LoadFile */ 316 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \ 317 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf)) 318 319 /* Graphics Output Protocol */ 320 #define __efi64_argmap_query_mode(gop, mode, size, info) \ 321 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info)) 322 323 /* TCG2 protocol */ 324 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \ 325 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev) 326 327 /* DXE services */ 328 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \ 329 (__efi64_split(phys), (desc)) 330 331 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \ 332 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 333 334 /* file protocol */ 335 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \ 336 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \ 337 __efi64_split(attr)) 338 339 #define __efi64_argmap_set_position(pos) (__efi64_split(pos)) 340 341 /* file system protocol */ 342 #define __efi64_argmap_open_volume(prot, file) \ 343 ((prot), efi64_zero_upper(file)) 344 345 /* Memory Attribute Protocol */ 346 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \ 347 ((protocol), __efi64_split(phys), __efi64_split(size), (flags)) 348 349 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \ 350 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 351 352 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \ 353 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 354 355 /* 356 * The macros below handle the plumbing for the argument mapping. To add a 357 * mapping for a specific EFI method, simply define a macro 358 * __efi64_argmap_<method name>, following the examples above. 359 */ 360 361 #define __efi64_thunk_map(inst, func, ...) \ 362 efi64_thunk(inst->mixed_mode.func, \ 363 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \ 364 (__VA_ARGS__))) 365 366 #define __efi64_argmap(mapped, args) \ 367 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args) 368 #define __efi64_argmap__0(mapped, args) __efi_eval mapped 369 #define __efi64_argmap__1(mapped, args) __efi_eval args 370 371 #define __efi_eat(...) 372 #define __efi_eval(...) __VA_ARGS__ 373 374 static inline efi_status_t __efi64_widen_efi_status(u64 status) 375 { 376 /* use rotate to move the value of bit #31 into position #63 */ 377 return ror64(rol32(status, 1), 1); 378 } 379 380 /* The macro below handles dispatching via the thunk if needed */ 381 382 #define efi_fn_call(inst, func, ...) \ 383 (efi_is_native() ? (inst)->func(__VA_ARGS__) \ 384 : efi_mixed_call((inst), func, ##__VA_ARGS__)) 385 386 #define efi_mixed_call(inst, func, ...) \ 387 _Generic(inst->func(__VA_ARGS__), \ 388 efi_status_t: \ 389 __efi64_widen_efi_status( \ 390 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \ 391 u64: ({ BUILD_BUG(); ULONG_MAX; }), \ 392 default: \ 393 (__typeof__(inst->func(__VA_ARGS__))) \ 394 __efi64_thunk_map(inst, func, ##__VA_ARGS__)) 395 396 #else /* CONFIG_EFI_MIXED */ 397 398 static inline bool efi_is_64bit(void) 399 { 400 return IS_ENABLED(CONFIG_X86_64); 401 } 402 403 #endif /* CONFIG_EFI_MIXED */ 404 405 extern bool efi_reboot_required(void); 406 extern bool efi_is_table_address(unsigned long phys_addr); 407 408 extern void efi_reserve_boot_services(void); 409 #else 410 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {} 411 static inline bool efi_reboot_required(void) 412 { 413 return false; 414 } 415 static inline bool efi_is_table_address(unsigned long phys_addr) 416 { 417 return false; 418 } 419 static inline void efi_reserve_boot_services(void) 420 { 421 } 422 #endif /* CONFIG_EFI */ 423 424 #ifdef CONFIG_EFI_FAKE_MEMMAP 425 extern void __init efi_fake_memmap_early(void); 426 extern void __init efi_fake_memmap(void); 427 #else 428 static inline void efi_fake_memmap_early(void) 429 { 430 } 431 432 static inline void efi_fake_memmap(void) 433 { 434 } 435 #endif 436 437 extern int __init efi_memmap_alloc(unsigned int num_entries, 438 struct efi_memory_map_data *data); 439 extern void __efi_memmap_free(u64 phys, unsigned long size, 440 unsigned long flags); 441 #define __efi_memmap_free __efi_memmap_free 442 443 extern int __init efi_memmap_install(struct efi_memory_map_data *data); 444 extern int __init efi_memmap_split_count(efi_memory_desc_t *md, 445 struct range *range); 446 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap, 447 void *buf, struct efi_mem_range *mem); 448 449 #define arch_ima_efi_boot_mode \ 450 ({ extern struct boot_params boot_params; boot_params.secure_boot; }) 451 452 #ifdef CONFIG_EFI_RUNTIME_MAP 453 int efi_get_runtime_map_size(void); 454 int efi_get_runtime_map_desc_size(void); 455 int efi_runtime_map_copy(void *buf, size_t bufsz); 456 #else 457 static inline int efi_get_runtime_map_size(void) 458 { 459 return 0; 460 } 461 462 static inline int efi_get_runtime_map_desc_size(void) 463 { 464 return 0; 465 } 466 467 static inline int efi_runtime_map_copy(void *buf, size_t bufsz) 468 { 469 return 0; 470 } 471 472 #endif 473 474 #endif /* _ASM_X86_EFI_H */ 475