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 #else /* !CONFIG_X86_32 */ 95 #define EFI_X86_KERNEL_ALLOC_LIMIT EFI_ALLOC_LIMIT 96 97 extern asmlinkage u64 __efi_call(void *fp, ...); 98 99 extern bool efi_disable_ibt_for_runtime; 100 101 #define efi_call(...) ({ \ 102 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \ 103 __efi_call(__VA_ARGS__); \ 104 }) 105 106 #undef arch_efi_call_virt 107 #define arch_efi_call_virt(p, f, args...) ({ \ 108 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \ 109 ret = efi_call((void *)p->f, args); \ 110 ibt_restore(ibt); \ 111 ret; \ 112 }) 113 114 #ifdef CONFIG_KASAN 115 /* 116 * CONFIG_KASAN may redefine memset to __memset. __memset function is present 117 * only in kernel binary. Since the EFI stub linked into a separate binary it 118 * doesn't have __memset(). So we should use standard memset from 119 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove. 120 */ 121 #undef memcpy 122 #undef memset 123 #undef memmove 124 #endif 125 126 #endif /* CONFIG_X86_32 */ 127 128 extern int __init efi_memblock_x86_reserve_range(void); 129 extern void __init efi_print_memmap(void); 130 extern void __init efi_map_region(efi_memory_desc_t *md); 131 extern void __init efi_map_region_fixed(efi_memory_desc_t *md); 132 extern void efi_sync_low_kernel_mappings(void); 133 extern int __init efi_alloc_page_tables(void); 134 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); 135 extern void __init efi_runtime_update_mappings(void); 136 extern void __init efi_dump_pagetable(void); 137 extern void __init efi_apply_memmap_quirks(void); 138 extern int __init efi_reuse_config(u64 tables, int nr_tables); 139 extern void efi_delete_dummy_variable(void); 140 extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr, 141 const struct pt_regs *regs); 142 extern void efi_unmap_boot_services(void); 143 144 void arch_efi_call_virt_setup(void); 145 void arch_efi_call_virt_teardown(void); 146 147 extern u64 efi_setup; 148 149 #ifdef CONFIG_EFI 150 extern u64 __efi64_thunk(u32, ...); 151 152 #define efi64_thunk(...) ({ \ 153 u64 __pad[3]; /* must have space for 3 args on the stack */ \ 154 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \ 155 __efi64_thunk(__VA_ARGS__, __pad); \ 156 }) 157 158 static inline bool efi_is_mixed(void) 159 { 160 if (!IS_ENABLED(CONFIG_EFI_MIXED)) 161 return false; 162 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT); 163 } 164 165 static inline bool efi_runtime_supported(void) 166 { 167 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT)) 168 return true; 169 170 return IS_ENABLED(CONFIG_EFI_MIXED); 171 } 172 173 extern void parse_efi_setup(u64 phys_addr, u32 data_len); 174 175 extern void efi_thunk_runtime_setup(void); 176 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size, 177 unsigned long descriptor_size, 178 u32 descriptor_version, 179 efi_memory_desc_t *virtual_map, 180 unsigned long systab_phys); 181 182 /* arch specific definitions used by the stub code */ 183 184 #ifdef CONFIG_EFI_MIXED 185 186 #define EFI_ALLOC_LIMIT (efi_is_64bit() ? ULONG_MAX : U32_MAX) 187 188 #define ARCH_HAS_EFISTUB_WRAPPERS 189 190 static inline bool efi_is_64bit(void) 191 { 192 extern const bool efi_is64; 193 194 return efi_is64; 195 } 196 197 static inline bool efi_is_native(void) 198 { 199 return efi_is_64bit(); 200 } 201 202 #define efi_table_attr(inst, attr) \ 203 (efi_is_native() ? (inst)->attr \ 204 : efi_mixed_table_attr((inst), attr)) 205 206 #define efi_mixed_table_attr(inst, attr) \ 207 (__typeof__(inst->attr)) \ 208 _Generic(inst->mixed_mode.attr, \ 209 u32: (unsigned long)(inst->mixed_mode.attr), \ 210 default: (inst->mixed_mode.attr)) 211 212 /* 213 * The following macros allow translating arguments if necessary from native to 214 * mixed mode. The use case for this is to initialize the upper 32 bits of 215 * output parameters, and where the 32-bit method requires a 64-bit argument, 216 * which must be split up into two arguments to be thunked properly. 217 * 218 * As examples, the AllocatePool boot service returns the address of the 219 * allocation, but it will not set the high 32 bits of the address. To ensure 220 * that the full 64-bit address is initialized, we zero-init the address before 221 * calling the thunk. 222 * 223 * The FreePages boot service takes a 64-bit physical address even in 32-bit 224 * mode. For the thunk to work correctly, a native 64-bit call of 225 * free_pages(addr, size) 226 * must be translated to 227 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size) 228 * so that the two 32-bit halves of addr get pushed onto the stack separately. 229 */ 230 231 static inline void *efi64_zero_upper(void *p) 232 { 233 if (p) 234 ((u32 *)p)[1] = 0; 235 return p; 236 } 237 238 static inline u32 efi64_convert_status(efi_status_t status) 239 { 240 return (u32)(status | (u64)status >> 32); 241 } 242 243 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32 244 245 #define __efi64_argmap_free_pages(addr, size) \ 246 ((addr), 0, (size)) 247 248 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \ 249 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver)) 250 251 #define __efi64_argmap_allocate_pool(type, size, buffer) \ 252 ((type), (size), efi64_zero_upper(buffer)) 253 254 #define __efi64_argmap_locate_handle_buffer(type, proto, key, num, buf) \ 255 ((type), (proto), (key), efi64_zero_upper(num), efi64_zero_upper(buf)) 256 257 #define __efi64_argmap_create_event(type, tpl, f, c, event) \ 258 ((type), (tpl), (f), (c), efi64_zero_upper(event)) 259 260 #define __efi64_argmap_set_timer(event, type, time) \ 261 ((event), (type), lower_32_bits(time), upper_32_bits(time)) 262 263 #define __efi64_argmap_wait_for_event(num, event, index) \ 264 ((num), (event), efi64_zero_upper(index)) 265 266 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \ 267 ((handle), (protocol), efi64_zero_upper(interface)) 268 269 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \ 270 ((protocol), (reg), efi64_zero_upper(interface)) 271 272 #define __efi64_argmap_locate_device_path(protocol, path, handle) \ 273 ((protocol), (path), efi64_zero_upper(handle)) 274 275 #define __efi64_argmap_exit(handle, status, size, data) \ 276 ((handle), efi64_convert_status(status), (size), (data)) 277 278 /* PCI I/O */ 279 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \ 280 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \ 281 efi64_zero_upper(dev), efi64_zero_upper(func)) 282 283 /* LoadFile */ 284 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \ 285 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf)) 286 287 /* Graphics Output Protocol */ 288 #define __efi64_argmap_query_mode(gop, mode, size, info) \ 289 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info)) 290 291 /* TCG2 protocol */ 292 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \ 293 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev) 294 295 /* DXE services */ 296 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \ 297 (__efi64_split(phys), (desc)) 298 299 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \ 300 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 301 302 /* file protocol */ 303 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \ 304 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \ 305 __efi64_split(attr)) 306 307 #define __efi64_argmap_set_position(pos) (__efi64_split(pos)) 308 309 /* file system protocol */ 310 #define __efi64_argmap_open_volume(prot, file) \ 311 ((prot), efi64_zero_upper(file)) 312 313 /* Memory Attribute Protocol */ 314 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \ 315 ((protocol), __efi64_split(phys), __efi64_split(size), (flags)) 316 317 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \ 318 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 319 320 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \ 321 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags)) 322 323 /* EFI SMBIOS protocol */ 324 #define __efi64_argmap_get_next(protocol, smbioshandle, type, record, phandle) \ 325 ((protocol), (smbioshandle), (type), efi64_zero_upper(record), \ 326 efi64_zero_upper(phandle)) 327 /* 328 * The macros below handle the plumbing for the argument mapping. To add a 329 * mapping for a specific EFI method, simply define a macro 330 * __efi64_argmap_<method name>, following the examples above. 331 */ 332 333 #define __efi64_thunk_map(inst, func, ...) \ 334 efi64_thunk(inst->mixed_mode.func, \ 335 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \ 336 (__VA_ARGS__))) 337 338 #define __efi64_argmap(mapped, args) \ 339 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args) 340 #define __efi64_argmap__0(mapped, args) __efi_eval mapped 341 #define __efi64_argmap__1(mapped, args) __efi_eval args 342 343 #define __efi_eat(...) 344 #define __efi_eval(...) __VA_ARGS__ 345 346 static inline efi_status_t __efi64_widen_efi_status(u64 status) 347 { 348 /* use rotate to move the value of bit #31 into position #63 */ 349 return ror64(rol32(status, 1), 1); 350 } 351 352 /* The macro below handles dispatching via the thunk if needed */ 353 354 #define efi_fn_call(inst, func, ...) \ 355 (efi_is_native() ? (inst)->func(__VA_ARGS__) \ 356 : efi_mixed_call((inst), func, ##__VA_ARGS__)) 357 358 #define efi_mixed_call(inst, func, ...) \ 359 _Generic(inst->func(__VA_ARGS__), \ 360 efi_status_t: \ 361 __efi64_widen_efi_status( \ 362 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \ 363 u64: ({ BUILD_BUG(); ULONG_MAX; }), \ 364 default: \ 365 (__typeof__(inst->func(__VA_ARGS__))) \ 366 __efi64_thunk_map(inst, func, ##__VA_ARGS__)) 367 368 #else /* CONFIG_EFI_MIXED */ 369 370 static inline bool efi_is_64bit(void) 371 { 372 return IS_ENABLED(CONFIG_X86_64); 373 } 374 375 #endif /* CONFIG_EFI_MIXED */ 376 377 extern bool efi_reboot_required(void); 378 extern bool efi_is_table_address(unsigned long phys_addr); 379 380 extern void efi_reserve_boot_services(void); 381 #else 382 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {} 383 static inline bool efi_reboot_required(void) 384 { 385 return false; 386 } 387 static inline bool efi_is_table_address(unsigned long phys_addr) 388 { 389 return false; 390 } 391 static inline void efi_reserve_boot_services(void) 392 { 393 } 394 #endif /* CONFIG_EFI */ 395 396 extern int __init efi_memmap_alloc(unsigned int num_entries, 397 struct efi_memory_map_data *data); 398 399 extern int __init efi_memmap_install(struct efi_memory_map_data *data); 400 extern int __init efi_memmap_split_count(efi_memory_desc_t *md, 401 struct range *range); 402 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap, 403 void *buf, struct efi_mem_range *mem); 404 405 enum efi_secureboot_mode __x86_efi_boot_mode(void); 406 407 #define arch_efi_boot_mode __x86_efi_boot_mode() 408 409 #ifdef CONFIG_EFI_RUNTIME_MAP 410 int efi_get_runtime_map_size(void); 411 int efi_get_runtime_map_desc_size(void); 412 int efi_runtime_map_copy(void *buf, size_t bufsz); 413 #else 414 static inline int efi_get_runtime_map_size(void) 415 { 416 return 0; 417 } 418 419 static inline int efi_get_runtime_map_desc_size(void) 420 { 421 return 0; 422 } 423 424 static inline int efi_runtime_map_copy(void *buf, size_t bufsz) 425 { 426 return 0; 427 } 428 429 #endif 430 431 #endif /* _ASM_X86_EFI_H */ 432