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 arch_efi_call_virt_setup() \ 94 ({ \ 95 efi_fpu_begin(); \ 96 firmware_restrict_branch_speculation_start(); \ 97 }) 98 99 #define arch_efi_call_virt_teardown() \ 100 ({ \ 101 firmware_restrict_branch_speculation_end(); \ 102 efi_fpu_end(); \ 103 }) 104 105 #else /* !CONFIG_X86_32 */ 106 107 #define EFI_LOADER_SIGNATURE "EL64" 108 109 extern asmlinkage u64 __efi_call(void *fp, ...); 110 111 extern bool efi_disable_ibt_for_runtime; 112 113 #define efi_call(...) ({ \ 114 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \ 115 __efi_call(__VA_ARGS__); \ 116 }) 117 118 #define arch_efi_call_virt_setup() \ 119 ({ \ 120 efi_sync_low_kernel_mappings(); \ 121 efi_fpu_begin(); \ 122 firmware_restrict_branch_speculation_start(); \ 123 efi_enter_mm(); \ 124 }) 125 126 #undef arch_efi_call_virt 127 #define arch_efi_call_virt(p, f, args...) ({ \ 128 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \ 129 ret = efi_call((void *)p->f, args); \ 130 ibt_restore(ibt); \ 131 ret; \ 132 }) 133 134 #define arch_efi_call_virt_teardown() \ 135 ({ \ 136 efi_leave_mm(); \ 137 firmware_restrict_branch_speculation_end(); \ 138 efi_fpu_end(); \ 139 }) 140 141 #ifdef CONFIG_KASAN 142 /* 143 * CONFIG_KASAN may redefine memset to __memset. __memset function is present 144 * only in kernel binary. Since the EFI stub linked into a separate binary it 145 * doesn't have __memset(). So we should use standard memset from 146 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove. 147 */ 148 #undef memcpy 149 #undef memset 150 #undef memmove 151 #endif 152 153 #endif /* CONFIG_X86_32 */ 154 155 extern int __init efi_memblock_x86_reserve_range(void); 156 extern void __init efi_print_memmap(void); 157 extern void __init efi_map_region(efi_memory_desc_t *md); 158 extern void __init efi_map_region_fixed(efi_memory_desc_t *md); 159 extern void efi_sync_low_kernel_mappings(void); 160 extern int __init efi_alloc_page_tables(void); 161 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); 162 extern void __init efi_runtime_update_mappings(void); 163 extern void __init efi_dump_pagetable(void); 164 extern void __init efi_apply_memmap_quirks(void); 165 extern int __init efi_reuse_config(u64 tables, int nr_tables); 166 extern void efi_delete_dummy_variable(void); 167 extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr); 168 extern void efi_free_boot_services(void); 169 170 void efi_enter_mm(void); 171 void efi_leave_mm(void); 172 173 /* kexec external ABI */ 174 struct efi_setup_data { 175 u64 fw_vendor; 176 u64 __unused; 177 u64 tables; 178 u64 smbios; 179 u64 reserved[8]; 180 }; 181 182 extern u64 efi_setup; 183 184 #ifdef CONFIG_EFI 185 extern u64 __efi64_thunk(u32, ...); 186 187 #define efi64_thunk(...) ({ \ 188 u64 __pad[3]; /* must have space for 3 args on the stack */ \ 189 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \ 190 __efi64_thunk(__VA_ARGS__, __pad); \ 191 }) 192 193 static inline bool efi_is_mixed(void) 194 { 195 if (!IS_ENABLED(CONFIG_EFI_MIXED)) 196 return false; 197 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT); 198 } 199 200 static inline bool efi_runtime_supported(void) 201 { 202 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT)) 203 return true; 204 205 return IS_ENABLED(CONFIG_EFI_MIXED); 206 } 207 208 extern void parse_efi_setup(u64 phys_addr, u32 data_len); 209 210 extern void efi_thunk_runtime_setup(void); 211 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size, 212 unsigned long descriptor_size, 213 u32 descriptor_version, 214 efi_memory_desc_t *virtual_map, 215 unsigned long systab_phys); 216 217 /* arch specific definitions used by the stub code */ 218 219 #ifdef CONFIG_EFI_MIXED 220 221 #define ARCH_HAS_EFISTUB_WRAPPERS 222 223 static inline bool efi_is_64bit(void) 224 { 225 extern const bool efi_is64; 226 227 return efi_is64; 228 } 229 230 static inline bool efi_is_native(void) 231 { 232 return efi_is_64bit(); 233 } 234 235 #define efi_table_attr(inst, attr) \ 236 (efi_is_native() ? (inst)->attr \ 237 : efi_mixed_table_attr((inst), attr)) 238 239 #define efi_mixed_table_attr(inst, attr) \ 240 (__typeof__(inst->attr)) \ 241 _Generic(inst->mixed_mode.attr, \ 242 u32: (unsigned long)(inst->mixed_mode.attr), \ 243 default: (inst->mixed_mode.attr)) 244 245 /* 246 * The following macros allow translating arguments if necessary from native to 247 * mixed mode. The use case for this is to initialize the upper 32 bits of 248 * output parameters, and where the 32-bit method requires a 64-bit argument, 249 * which must be split up into two arguments to be thunked properly. 250 * 251 * As examples, the AllocatePool boot service returns the address of the 252 * allocation, but it will not set the high 32 bits of the address. To ensure 253 * that the full 64-bit address is initialized, we zero-init the address before 254 * calling the thunk. 255 * 256 * The FreePages boot service takes a 64-bit physical address even in 32-bit 257 * mode. For the thunk to work correctly, a native 64-bit call of 258 * free_pages(addr, size) 259 * must be translated to 260 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size) 261 * so that the two 32-bit halves of addr get pushed onto the stack separately. 262 */ 263 264 static inline void *efi64_zero_upper(void *p) 265 { 266 ((u32 *)p)[1] = 0; 267 return p; 268 } 269 270 static inline u32 efi64_convert_status(efi_status_t status) 271 { 272 return (u32)(status | (u64)status >> 32); 273 } 274 275 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32 276 277 #define __efi64_argmap_free_pages(addr, size) \ 278 ((addr), 0, (size)) 279 280 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \ 281 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver)) 282 283 #define __efi64_argmap_allocate_pool(type, size, buffer) \ 284 ((type), (size), efi64_zero_upper(buffer)) 285 286 #define __efi64_argmap_create_event(type, tpl, f, c, event) \ 287 ((type), (tpl), (f), (c), efi64_zero_upper(event)) 288 289 #define __efi64_argmap_set_timer(event, type, time) \ 290 ((event), (type), lower_32_bits(time), upper_32_bits(time)) 291 292 #define __efi64_argmap_wait_for_event(num, event, index) \ 293 ((num), (event), efi64_zero_upper(index)) 294 295 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \ 296 ((handle), (protocol), efi64_zero_upper(interface)) 297 298 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \ 299 ((protocol), (reg), efi64_zero_upper(interface)) 300 301 #define __efi64_argmap_locate_device_path(protocol, path, handle) \ 302 ((protocol), (path), efi64_zero_upper(handle)) 303 304 #define __efi64_argmap_exit(handle, status, size, data) \ 305 ((handle), efi64_convert_status(status), (size), (data)) 306 307 /* PCI I/O */ 308 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \ 309 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \ 310 efi64_zero_upper(dev), efi64_zero_upper(func)) 311 312 /* LoadFile */ 313 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \ 314 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf)) 315 316 /* Graphics Output Protocol */ 317 #define __efi64_argmap_query_mode(gop, mode, size, info) \ 318 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info)) 319 320 /* TCG2 protocol */ 321 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \ 322 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev) 323 324 /* DXE services */ 325 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \ 326 (__efi64_split(phys), (desc)) 327 328 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \ 329 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 330 331 /* file protocol */ 332 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \ 333 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \ 334 __efi64_split(attr)) 335 336 #define __efi64_argmap_set_position(pos) (__efi64_split(pos)) 337 338 /* file system protocol */ 339 #define __efi64_argmap_open_volume(prot, file) \ 340 ((prot), efi64_zero_upper(file)) 341 342 /* Memory Attribute Protocol */ 343 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \ 344 ((protocol), __efi64_split(phys), __efi64_split(size), (flags)) 345 346 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \ 347 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 348 349 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \ 350 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 351 352 /* 353 * The macros below handle the plumbing for the argument mapping. To add a 354 * mapping for a specific EFI method, simply define a macro 355 * __efi64_argmap_<method name>, following the examples above. 356 */ 357 358 #define __efi64_thunk_map(inst, func, ...) \ 359 efi64_thunk(inst->mixed_mode.func, \ 360 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \ 361 (__VA_ARGS__))) 362 363 #define __efi64_argmap(mapped, args) \ 364 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args) 365 #define __efi64_argmap__0(mapped, args) __efi_eval mapped 366 #define __efi64_argmap__1(mapped, args) __efi_eval args 367 368 #define __efi_eat(...) 369 #define __efi_eval(...) __VA_ARGS__ 370 371 static inline efi_status_t __efi64_widen_efi_status(u64 status) 372 { 373 /* use rotate to move the value of bit #31 into position #63 */ 374 return ror64(rol32(status, 1), 1); 375 } 376 377 /* The macro below handles dispatching via the thunk if needed */ 378 379 #define efi_fn_call(inst, func, ...) \ 380 (efi_is_native() ? (inst)->func(__VA_ARGS__) \ 381 : efi_mixed_call((inst), func, ##__VA_ARGS__)) 382 383 #define efi_mixed_call(inst, func, ...) \ 384 _Generic(inst->func(__VA_ARGS__), \ 385 efi_status_t: \ 386 __efi64_widen_efi_status( \ 387 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \ 388 u64: ({ BUILD_BUG(); ULONG_MAX; }), \ 389 default: \ 390 (__typeof__(inst->func(__VA_ARGS__))) \ 391 __efi64_thunk_map(inst, func, ##__VA_ARGS__)) 392 393 #else /* CONFIG_EFI_MIXED */ 394 395 static inline bool efi_is_64bit(void) 396 { 397 return IS_ENABLED(CONFIG_X86_64); 398 } 399 400 #endif /* CONFIG_EFI_MIXED */ 401 402 extern bool efi_reboot_required(void); 403 extern bool efi_is_table_address(unsigned long phys_addr); 404 405 extern void efi_reserve_boot_services(void); 406 #else 407 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {} 408 static inline bool efi_reboot_required(void) 409 { 410 return false; 411 } 412 static inline bool efi_is_table_address(unsigned long phys_addr) 413 { 414 return false; 415 } 416 static inline void efi_reserve_boot_services(void) 417 { 418 } 419 #endif /* CONFIG_EFI */ 420 421 #ifdef CONFIG_EFI_FAKE_MEMMAP 422 extern void __init efi_fake_memmap_early(void); 423 extern void __init efi_fake_memmap(void); 424 #else 425 static inline void efi_fake_memmap_early(void) 426 { 427 } 428 429 static inline void efi_fake_memmap(void) 430 { 431 } 432 #endif 433 434 extern int __init efi_memmap_alloc(unsigned int num_entries, 435 struct efi_memory_map_data *data); 436 extern void __efi_memmap_free(u64 phys, unsigned long size, 437 unsigned long flags); 438 #define __efi_memmap_free __efi_memmap_free 439 440 extern int __init efi_memmap_install(struct efi_memory_map_data *data); 441 extern int __init efi_memmap_split_count(efi_memory_desc_t *md, 442 struct range *range); 443 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap, 444 void *buf, struct efi_mem_range *mem); 445 446 #define arch_ima_efi_boot_mode \ 447 ({ extern struct boot_params boot_params; boot_params.secure_boot; }) 448 449 #ifdef CONFIG_EFI_RUNTIME_MAP 450 int efi_get_runtime_map_size(void); 451 int efi_get_runtime_map_desc_size(void); 452 int efi_runtime_map_copy(void *buf, size_t bufsz); 453 #else 454 static inline int efi_get_runtime_map_size(void) 455 { 456 return 0; 457 } 458 459 static inline int efi_get_runtime_map_desc_size(void) 460 { 461 return 0; 462 } 463 464 static inline int efi_runtime_map_copy(void *buf, size_t bufsz) 465 { 466 return 0; 467 } 468 469 #endif 470 471 #endif /* _ASM_X86_EFI_H */ 472