1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * efi.c - EFI subsystem 4 * 5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> 6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> 7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no> 8 * 9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported, 10 * allowing the efivarfs to be mounted or the efivars module to be loaded. 11 * The existance of /sys/firmware/efi may also be used by userspace to 12 * determine that the system supports EFI. 13 */ 14 15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 16 17 #include <linux/kobject.h> 18 #include <linux/module.h> 19 #include <linux/init.h> 20 #include <linux/debugfs.h> 21 #include <linux/device.h> 22 #include <linux/efi.h> 23 #include <linux/of.h> 24 #include <linux/io.h> 25 #include <linux/kexec.h> 26 #include <linux/platform_device.h> 27 #include <linux/random.h> 28 #include <linux/reboot.h> 29 #include <linux/slab.h> 30 #include <linux/acpi.h> 31 #include <linux/ucs2_string.h> 32 #include <linux/memblock.h> 33 #include <linux/security.h> 34 35 #include <asm/early_ioremap.h> 36 37 struct efi __read_mostly efi = { 38 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL, 39 .acpi = EFI_INVALID_TABLE_ADDR, 40 .acpi20 = EFI_INVALID_TABLE_ADDR, 41 .smbios = EFI_INVALID_TABLE_ADDR, 42 .smbios3 = EFI_INVALID_TABLE_ADDR, 43 .esrt = EFI_INVALID_TABLE_ADDR, 44 .tpm_log = EFI_INVALID_TABLE_ADDR, 45 .tpm_final_log = EFI_INVALID_TABLE_ADDR, 46 #ifdef CONFIG_LOAD_UEFI_KEYS 47 .mokvar_table = EFI_INVALID_TABLE_ADDR, 48 #endif 49 #ifdef CONFIG_EFI_COCO_SECRET 50 .coco_secret = EFI_INVALID_TABLE_ADDR, 51 #endif 52 }; 53 EXPORT_SYMBOL(efi); 54 55 unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR; 56 static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; 57 static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR; 58 59 struct mm_struct efi_mm = { 60 .mm_rb = RB_ROOT, 61 .mm_users = ATOMIC_INIT(2), 62 .mm_count = ATOMIC_INIT(1), 63 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq), 64 MMAP_LOCK_INITIALIZER(efi_mm) 65 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), 66 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), 67 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0}, 68 }; 69 70 struct workqueue_struct *efi_rts_wq; 71 72 static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME); 73 static int __init setup_noefi(char *arg) 74 { 75 disable_runtime = true; 76 return 0; 77 } 78 early_param("noefi", setup_noefi); 79 80 bool efi_runtime_disabled(void) 81 { 82 return disable_runtime; 83 } 84 85 bool __pure __efi_soft_reserve_enabled(void) 86 { 87 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE); 88 } 89 90 static int __init parse_efi_cmdline(char *str) 91 { 92 if (!str) { 93 pr_warn("need at least one option\n"); 94 return -EINVAL; 95 } 96 97 if (parse_option_str(str, "debug")) 98 set_bit(EFI_DBG, &efi.flags); 99 100 if (parse_option_str(str, "noruntime")) 101 disable_runtime = true; 102 103 if (parse_option_str(str, "runtime")) 104 disable_runtime = false; 105 106 if (parse_option_str(str, "nosoftreserve")) 107 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags); 108 109 return 0; 110 } 111 early_param("efi", parse_efi_cmdline); 112 113 struct kobject *efi_kobj; 114 115 /* 116 * Let's not leave out systab information that snuck into 117 * the efivars driver 118 * Note, do not add more fields in systab sysfs file as it breaks sysfs 119 * one value per file rule! 120 */ 121 static ssize_t systab_show(struct kobject *kobj, 122 struct kobj_attribute *attr, char *buf) 123 { 124 char *str = buf; 125 126 if (!kobj || !buf) 127 return -EINVAL; 128 129 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) 130 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); 131 if (efi.acpi != EFI_INVALID_TABLE_ADDR) 132 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); 133 /* 134 * If both SMBIOS and SMBIOS3 entry points are implemented, the 135 * SMBIOS3 entry point shall be preferred, so we list it first to 136 * let applications stop parsing after the first match. 137 */ 138 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) 139 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3); 140 if (efi.smbios != EFI_INVALID_TABLE_ADDR) 141 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); 142 143 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86)) 144 str = efi_systab_show_arch(str); 145 146 return str - buf; 147 } 148 149 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); 150 151 static ssize_t fw_platform_size_show(struct kobject *kobj, 152 struct kobj_attribute *attr, char *buf) 153 { 154 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); 155 } 156 157 extern __weak struct kobj_attribute efi_attr_fw_vendor; 158 extern __weak struct kobj_attribute efi_attr_runtime; 159 extern __weak struct kobj_attribute efi_attr_config_table; 160 static struct kobj_attribute efi_attr_fw_platform_size = 161 __ATTR_RO(fw_platform_size); 162 163 static struct attribute *efi_subsys_attrs[] = { 164 &efi_attr_systab.attr, 165 &efi_attr_fw_platform_size.attr, 166 &efi_attr_fw_vendor.attr, 167 &efi_attr_runtime.attr, 168 &efi_attr_config_table.attr, 169 NULL, 170 }; 171 172 umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, 173 int n) 174 { 175 return attr->mode; 176 } 177 178 static const struct attribute_group efi_subsys_attr_group = { 179 .attrs = efi_subsys_attrs, 180 .is_visible = efi_attr_is_visible, 181 }; 182 183 static struct efivars generic_efivars; 184 static struct efivar_operations generic_ops; 185 186 static int generic_ops_register(void) 187 { 188 generic_ops.get_variable = efi.get_variable; 189 generic_ops.get_next_variable = efi.get_next_variable; 190 generic_ops.query_variable_store = efi_query_variable_store; 191 192 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) { 193 generic_ops.set_variable = efi.set_variable; 194 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; 195 } 196 return efivars_register(&generic_efivars, &generic_ops, efi_kobj); 197 } 198 199 static void generic_ops_unregister(void) 200 { 201 efivars_unregister(&generic_efivars); 202 } 203 204 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS 205 #define EFIVAR_SSDT_NAME_MAX 16UL 206 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; 207 static int __init efivar_ssdt_setup(char *str) 208 { 209 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); 210 211 if (ret) 212 return ret; 213 214 if (strlen(str) < sizeof(efivar_ssdt)) 215 memcpy(efivar_ssdt, str, strlen(str)); 216 else 217 pr_warn("efivar_ssdt: name too long: %s\n", str); 218 return 1; 219 } 220 __setup("efivar_ssdt=", efivar_ssdt_setup); 221 222 static __init int efivar_ssdt_load(void) 223 { 224 unsigned long name_size = 256; 225 efi_char16_t *name = NULL; 226 efi_status_t status; 227 efi_guid_t guid; 228 229 if (!efivar_ssdt[0]) 230 return 0; 231 232 name = kzalloc(name_size, GFP_KERNEL); 233 if (!name) 234 return -ENOMEM; 235 236 for (;;) { 237 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 238 unsigned long data_size = 0; 239 void *data; 240 int limit; 241 242 status = efi.get_next_variable(&name_size, name, &guid); 243 if (status == EFI_NOT_FOUND) { 244 break; 245 } else if (status == EFI_BUFFER_TOO_SMALL) { 246 name = krealloc(name, name_size, GFP_KERNEL); 247 if (!name) 248 return -ENOMEM; 249 continue; 250 } 251 252 limit = min(EFIVAR_SSDT_NAME_MAX, name_size); 253 ucs2_as_utf8(utf8_name, name, limit - 1); 254 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 255 continue; 256 257 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid); 258 259 status = efi.get_variable(name, &guid, NULL, &data_size, NULL); 260 if (status != EFI_BUFFER_TOO_SMALL || !data_size) 261 return -EIO; 262 263 data = kmalloc(data_size, GFP_KERNEL); 264 if (!data) 265 return -ENOMEM; 266 267 status = efi.get_variable(name, &guid, NULL, &data_size, data); 268 if (status == EFI_SUCCESS) { 269 acpi_status ret = acpi_load_table(data, NULL); 270 if (ret) 271 pr_err("failed to load table: %u\n", ret); 272 } else { 273 pr_err("failed to get var data: 0x%lx\n", status); 274 } 275 kfree(data); 276 } 277 return 0; 278 } 279 #else 280 static inline int efivar_ssdt_load(void) { return 0; } 281 #endif 282 283 #ifdef CONFIG_DEBUG_FS 284 285 #define EFI_DEBUGFS_MAX_BLOBS 32 286 287 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; 288 289 static void __init efi_debugfs_init(void) 290 { 291 struct dentry *efi_debugfs; 292 efi_memory_desc_t *md; 293 char name[32]; 294 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; 295 int i = 0; 296 297 efi_debugfs = debugfs_create_dir("efi", NULL); 298 if (IS_ERR_OR_NULL(efi_debugfs)) 299 return; 300 301 for_each_efi_memory_desc(md) { 302 switch (md->type) { 303 case EFI_BOOT_SERVICES_CODE: 304 snprintf(name, sizeof(name), "boot_services_code%d", 305 type_count[md->type]++); 306 break; 307 case EFI_BOOT_SERVICES_DATA: 308 snprintf(name, sizeof(name), "boot_services_data%d", 309 type_count[md->type]++); 310 break; 311 default: 312 continue; 313 } 314 315 if (i >= EFI_DEBUGFS_MAX_BLOBS) { 316 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n", 317 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); 318 break; 319 } 320 321 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; 322 debugfs_blob[i].data = memremap(md->phys_addr, 323 debugfs_blob[i].size, 324 MEMREMAP_WB); 325 if (!debugfs_blob[i].data) 326 continue; 327 328 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); 329 i++; 330 } 331 } 332 #else 333 static inline void efi_debugfs_init(void) {} 334 #endif 335 336 /* 337 * We register the efi subsystem with the firmware subsystem and the 338 * efivars subsystem with the efi subsystem, if the system was booted with 339 * EFI. 340 */ 341 static int __init efisubsys_init(void) 342 { 343 int error; 344 345 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 346 efi.runtime_supported_mask = 0; 347 348 if (!efi_enabled(EFI_BOOT)) 349 return 0; 350 351 if (efi.runtime_supported_mask) { 352 /* 353 * Since we process only one efi_runtime_service() at a time, an 354 * ordered workqueue (which creates only one execution context) 355 * should suffice for all our needs. 356 */ 357 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 358 if (!efi_rts_wq) { 359 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 360 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 361 efi.runtime_supported_mask = 0; 362 return 0; 363 } 364 } 365 366 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES)) 367 platform_device_register_simple("rtc-efi", 0, NULL, 0); 368 369 /* We register the efi directory at /sys/firmware/efi */ 370 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 371 if (!efi_kobj) { 372 pr_err("efi: Firmware registration failed.\n"); 373 destroy_workqueue(efi_rts_wq); 374 return -ENOMEM; 375 } 376 377 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 378 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) { 379 error = generic_ops_register(); 380 if (error) 381 goto err_put; 382 efivar_ssdt_load(); 383 platform_device_register_simple("efivars", 0, NULL, 0); 384 } 385 386 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 387 if (error) { 388 pr_err("efi: Sysfs attribute export failed with error %d.\n", 389 error); 390 goto err_unregister; 391 } 392 393 error = efi_runtime_map_init(efi_kobj); 394 if (error) 395 goto err_remove_group; 396 397 /* and the standard mountpoint for efivarfs */ 398 error = sysfs_create_mount_point(efi_kobj, "efivars"); 399 if (error) { 400 pr_err("efivars: Subsystem registration failed.\n"); 401 goto err_remove_group; 402 } 403 404 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) 405 efi_debugfs_init(); 406 407 #ifdef CONFIG_EFI_COCO_SECRET 408 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR) 409 platform_device_register_simple("efi_secret", 0, NULL, 0); 410 #endif 411 412 return 0; 413 414 err_remove_group: 415 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 416 err_unregister: 417 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 418 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) 419 generic_ops_unregister(); 420 err_put: 421 kobject_put(efi_kobj); 422 destroy_workqueue(efi_rts_wq); 423 return error; 424 } 425 426 subsys_initcall(efisubsys_init); 427 428 void __init efi_find_mirror(void) 429 { 430 efi_memory_desc_t *md; 431 u64 mirror_size = 0, total_size = 0; 432 433 if (!efi_enabled(EFI_MEMMAP)) 434 return; 435 436 for_each_efi_memory_desc(md) { 437 unsigned long long start = md->phys_addr; 438 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT; 439 440 total_size += size; 441 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) { 442 memblock_mark_mirror(start, size); 443 mirror_size += size; 444 } 445 } 446 if (mirror_size) 447 pr_info("Memory: %lldM/%lldM mirrored memory\n", 448 mirror_size>>20, total_size>>20); 449 } 450 451 /* 452 * Find the efi memory descriptor for a given physical address. Given a 453 * physical address, determine if it exists within an EFI Memory Map entry, 454 * and if so, populate the supplied memory descriptor with the appropriate 455 * data. 456 */ 457 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 458 { 459 efi_memory_desc_t *md; 460 461 if (!efi_enabled(EFI_MEMMAP)) { 462 pr_err_once("EFI_MEMMAP is not enabled.\n"); 463 return -EINVAL; 464 } 465 466 if (!out_md) { 467 pr_err_once("out_md is null.\n"); 468 return -EINVAL; 469 } 470 471 for_each_efi_memory_desc(md) { 472 u64 size; 473 u64 end; 474 475 size = md->num_pages << EFI_PAGE_SHIFT; 476 end = md->phys_addr + size; 477 if (phys_addr >= md->phys_addr && phys_addr < end) { 478 memcpy(out_md, md, sizeof(*out_md)); 479 return 0; 480 } 481 } 482 return -ENOENT; 483 } 484 485 /* 486 * Calculate the highest address of an efi memory descriptor. 487 */ 488 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 489 { 490 u64 size = md->num_pages << EFI_PAGE_SHIFT; 491 u64 end = md->phys_addr + size; 492 return end; 493 } 494 495 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 496 497 /** 498 * efi_mem_reserve - Reserve an EFI memory region 499 * @addr: Physical address to reserve 500 * @size: Size of reservation 501 * 502 * Mark a region as reserved from general kernel allocation and 503 * prevent it being released by efi_free_boot_services(). 504 * 505 * This function should be called drivers once they've parsed EFI 506 * configuration tables to figure out where their data lives, e.g. 507 * efi_esrt_init(). 508 */ 509 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 510 { 511 if (!memblock_is_region_reserved(addr, size)) 512 memblock_reserve(addr, size); 513 514 /* 515 * Some architectures (x86) reserve all boot services ranges 516 * until efi_free_boot_services() because of buggy firmware 517 * implementations. This means the above memblock_reserve() is 518 * superfluous on x86 and instead what it needs to do is 519 * ensure the @start, @size is not freed. 520 */ 521 efi_arch_mem_reserve(addr, size); 522 } 523 524 static const efi_config_table_type_t common_tables[] __initconst = { 525 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" }, 526 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" }, 527 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" }, 528 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" }, 529 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" }, 530 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" }, 531 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" }, 532 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" }, 533 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 534 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 535 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 536 #ifdef CONFIG_EFI_RCI2_TABLE 537 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 538 #endif 539 #ifdef CONFIG_LOAD_UEFI_KEYS 540 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 541 #endif 542 #ifdef CONFIG_EFI_COCO_SECRET 543 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 544 #endif 545 {}, 546 }; 547 548 static __init int match_config_table(const efi_guid_t *guid, 549 unsigned long table, 550 const efi_config_table_type_t *table_types) 551 { 552 int i; 553 554 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 555 if (!efi_guidcmp(*guid, table_types[i].guid)) { 556 *(table_types[i].ptr) = table; 557 if (table_types[i].name[0]) 558 pr_cont("%s=0x%lx ", 559 table_types[i].name, table); 560 return 1; 561 } 562 } 563 564 return 0; 565 } 566 567 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 568 int count, 569 const efi_config_table_type_t *arch_tables) 570 { 571 const efi_config_table_64_t *tbl64 = (void *)config_tables; 572 const efi_config_table_32_t *tbl32 = (void *)config_tables; 573 const efi_guid_t *guid; 574 unsigned long table; 575 int i; 576 577 pr_info(""); 578 for (i = 0; i < count; i++) { 579 if (!IS_ENABLED(CONFIG_X86)) { 580 guid = &config_tables[i].guid; 581 table = (unsigned long)config_tables[i].table; 582 } else if (efi_enabled(EFI_64BIT)) { 583 guid = &tbl64[i].guid; 584 table = tbl64[i].table; 585 586 if (IS_ENABLED(CONFIG_X86_32) && 587 tbl64[i].table > U32_MAX) { 588 pr_cont("\n"); 589 pr_err("Table located above 4GB, disabling EFI.\n"); 590 return -EINVAL; 591 } 592 } else { 593 guid = &tbl32[i].guid; 594 table = tbl32[i].table; 595 } 596 597 if (!match_config_table(guid, table, common_tables) && arch_tables) 598 match_config_table(guid, table, arch_tables); 599 } 600 pr_cont("\n"); 601 set_bit(EFI_CONFIG_TABLES, &efi.flags); 602 603 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 604 struct linux_efi_random_seed *seed; 605 u32 size = 0; 606 607 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 608 if (seed != NULL) { 609 size = READ_ONCE(seed->size); 610 early_memunmap(seed, sizeof(*seed)); 611 } else { 612 pr_err("Could not map UEFI random seed!\n"); 613 } 614 if (size > 0) { 615 seed = early_memremap(efi_rng_seed, 616 sizeof(*seed) + size); 617 if (seed != NULL) { 618 pr_notice("seeding entropy pool\n"); 619 add_bootloader_randomness(seed->bits, size); 620 early_memunmap(seed, sizeof(*seed) + size); 621 } else { 622 pr_err("Could not map UEFI random seed!\n"); 623 } 624 } 625 } 626 627 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 628 efi_memattr_init(); 629 630 efi_tpm_eventlog_init(); 631 632 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 633 unsigned long prsv = mem_reserve; 634 635 while (prsv) { 636 struct linux_efi_memreserve *rsv; 637 u8 *p; 638 639 /* 640 * Just map a full page: that is what we will get 641 * anyway, and it permits us to map the entire entry 642 * before knowing its size. 643 */ 644 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 645 PAGE_SIZE); 646 if (p == NULL) { 647 pr_err("Could not map UEFI memreserve entry!\n"); 648 return -ENOMEM; 649 } 650 651 rsv = (void *)(p + prsv % PAGE_SIZE); 652 653 /* reserve the entry itself */ 654 memblock_reserve(prsv, 655 struct_size(rsv, entry, rsv->size)); 656 657 for (i = 0; i < atomic_read(&rsv->count); i++) { 658 memblock_reserve(rsv->entry[i].base, 659 rsv->entry[i].size); 660 } 661 662 prsv = rsv->next; 663 early_memunmap(p, PAGE_SIZE); 664 } 665 } 666 667 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 668 efi_rt_properties_table_t *tbl; 669 670 tbl = early_memremap(rt_prop, sizeof(*tbl)); 671 if (tbl) { 672 efi.runtime_supported_mask &= tbl->runtime_services_supported; 673 early_memunmap(tbl, sizeof(*tbl)); 674 } 675 } 676 677 return 0; 678 } 679 680 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr, 681 int min_major_version) 682 { 683 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 684 pr_err("System table signature incorrect!\n"); 685 return -EINVAL; 686 } 687 688 if ((systab_hdr->revision >> 16) < min_major_version) 689 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n", 690 systab_hdr->revision >> 16, 691 systab_hdr->revision & 0xffff, 692 min_major_version); 693 694 return 0; 695 } 696 697 #ifndef CONFIG_IA64 698 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 699 size_t size) 700 { 701 const efi_char16_t *ret; 702 703 ret = early_memremap_ro(fw_vendor, size); 704 if (!ret) 705 pr_err("Could not map the firmware vendor!\n"); 706 return ret; 707 } 708 709 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 710 { 711 early_memunmap((void *)fw_vendor, size); 712 } 713 #else 714 #define map_fw_vendor(p, s) __va(p) 715 #define unmap_fw_vendor(v, s) 716 #endif 717 718 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 719 unsigned long fw_vendor) 720 { 721 char vendor[100] = "unknown"; 722 const efi_char16_t *c16; 723 size_t i; 724 725 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 726 if (c16) { 727 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 728 vendor[i] = c16[i]; 729 vendor[i] = '\0'; 730 731 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 732 } 733 734 pr_info("EFI v%u.%.02u by %s\n", 735 systab_hdr->revision >> 16, 736 systab_hdr->revision & 0xffff, 737 vendor); 738 739 if (IS_ENABLED(CONFIG_X86_64) && 740 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 741 !strcmp(vendor, "Apple")) { 742 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 743 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 744 } 745 } 746 747 static __initdata char memory_type_name[][13] = { 748 "Reserved", 749 "Loader Code", 750 "Loader Data", 751 "Boot Code", 752 "Boot Data", 753 "Runtime Code", 754 "Runtime Data", 755 "Conventional", 756 "Unusable", 757 "ACPI Reclaim", 758 "ACPI Mem NVS", 759 "MMIO", 760 "MMIO Port", 761 "PAL Code", 762 "Persistent", 763 }; 764 765 char * __init efi_md_typeattr_format(char *buf, size_t size, 766 const efi_memory_desc_t *md) 767 { 768 char *pos; 769 int type_len; 770 u64 attr; 771 772 pos = buf; 773 if (md->type >= ARRAY_SIZE(memory_type_name)) 774 type_len = snprintf(pos, size, "[type=%u", md->type); 775 else 776 type_len = snprintf(pos, size, "[%-*s", 777 (int)(sizeof(memory_type_name[0]) - 1), 778 memory_type_name[md->type]); 779 if (type_len >= size) 780 return buf; 781 782 pos += type_len; 783 size -= type_len; 784 785 attr = md->attribute; 786 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 787 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 788 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 789 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 790 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 791 snprintf(pos, size, "|attr=0x%016llx]", 792 (unsigned long long)attr); 793 else 794 snprintf(pos, size, 795 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 796 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 797 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 798 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 799 attr & EFI_MEMORY_SP ? "SP" : "", 800 attr & EFI_MEMORY_NV ? "NV" : "", 801 attr & EFI_MEMORY_XP ? "XP" : "", 802 attr & EFI_MEMORY_RP ? "RP" : "", 803 attr & EFI_MEMORY_WP ? "WP" : "", 804 attr & EFI_MEMORY_RO ? "RO" : "", 805 attr & EFI_MEMORY_UCE ? "UCE" : "", 806 attr & EFI_MEMORY_WB ? "WB" : "", 807 attr & EFI_MEMORY_WT ? "WT" : "", 808 attr & EFI_MEMORY_WC ? "WC" : "", 809 attr & EFI_MEMORY_UC ? "UC" : ""); 810 return buf; 811 } 812 813 /* 814 * IA64 has a funky EFI memory map that doesn't work the same way as 815 * other architectures. 816 */ 817 #ifndef CONFIG_IA64 818 /* 819 * efi_mem_attributes - lookup memmap attributes for physical address 820 * @phys_addr: the physical address to lookup 821 * 822 * Search in the EFI memory map for the region covering 823 * @phys_addr. Returns the EFI memory attributes if the region 824 * was found in the memory map, 0 otherwise. 825 */ 826 u64 efi_mem_attributes(unsigned long phys_addr) 827 { 828 efi_memory_desc_t *md; 829 830 if (!efi_enabled(EFI_MEMMAP)) 831 return 0; 832 833 for_each_efi_memory_desc(md) { 834 if ((md->phys_addr <= phys_addr) && 835 (phys_addr < (md->phys_addr + 836 (md->num_pages << EFI_PAGE_SHIFT)))) 837 return md->attribute; 838 } 839 return 0; 840 } 841 842 /* 843 * efi_mem_type - lookup memmap type for physical address 844 * @phys_addr: the physical address to lookup 845 * 846 * Search in the EFI memory map for the region covering @phys_addr. 847 * Returns the EFI memory type if the region was found in the memory 848 * map, -EINVAL otherwise. 849 */ 850 int efi_mem_type(unsigned long phys_addr) 851 { 852 const efi_memory_desc_t *md; 853 854 if (!efi_enabled(EFI_MEMMAP)) 855 return -ENOTSUPP; 856 857 for_each_efi_memory_desc(md) { 858 if ((md->phys_addr <= phys_addr) && 859 (phys_addr < (md->phys_addr + 860 (md->num_pages << EFI_PAGE_SHIFT)))) 861 return md->type; 862 } 863 return -EINVAL; 864 } 865 #endif 866 867 int efi_status_to_err(efi_status_t status) 868 { 869 int err; 870 871 switch (status) { 872 case EFI_SUCCESS: 873 err = 0; 874 break; 875 case EFI_INVALID_PARAMETER: 876 err = -EINVAL; 877 break; 878 case EFI_OUT_OF_RESOURCES: 879 err = -ENOSPC; 880 break; 881 case EFI_DEVICE_ERROR: 882 err = -EIO; 883 break; 884 case EFI_WRITE_PROTECTED: 885 err = -EROFS; 886 break; 887 case EFI_SECURITY_VIOLATION: 888 err = -EACCES; 889 break; 890 case EFI_NOT_FOUND: 891 err = -ENOENT; 892 break; 893 case EFI_ABORTED: 894 err = -EINTR; 895 break; 896 default: 897 err = -EINVAL; 898 } 899 900 return err; 901 } 902 EXPORT_SYMBOL_GPL(efi_status_to_err); 903 904 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 905 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 906 907 static int __init efi_memreserve_map_root(void) 908 { 909 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 910 return -ENODEV; 911 912 efi_memreserve_root = memremap(mem_reserve, 913 sizeof(*efi_memreserve_root), 914 MEMREMAP_WB); 915 if (WARN_ON_ONCE(!efi_memreserve_root)) 916 return -ENOMEM; 917 return 0; 918 } 919 920 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 921 { 922 struct resource *res, *parent; 923 int ret; 924 925 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 926 if (!res) 927 return -ENOMEM; 928 929 res->name = "reserved"; 930 res->flags = IORESOURCE_MEM; 931 res->start = addr; 932 res->end = addr + size - 1; 933 934 /* we expect a conflict with a 'System RAM' region */ 935 parent = request_resource_conflict(&iomem_resource, res); 936 ret = parent ? request_resource(parent, res) : 0; 937 938 /* 939 * Given that efi_mem_reserve_iomem() can be called at any 940 * time, only call memblock_reserve() if the architecture 941 * keeps the infrastructure around. 942 */ 943 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 944 memblock_reserve(addr, size); 945 946 return ret; 947 } 948 949 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 950 { 951 struct linux_efi_memreserve *rsv; 952 unsigned long prsv; 953 int rc, index; 954 955 if (efi_memreserve_root == (void *)ULONG_MAX) 956 return -ENODEV; 957 958 if (!efi_memreserve_root) { 959 rc = efi_memreserve_map_root(); 960 if (rc) 961 return rc; 962 } 963 964 /* first try to find a slot in an existing linked list entry */ 965 for (prsv = efi_memreserve_root->next; prsv; ) { 966 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 967 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 968 if (index < rsv->size) { 969 rsv->entry[index].base = addr; 970 rsv->entry[index].size = size; 971 972 memunmap(rsv); 973 return efi_mem_reserve_iomem(addr, size); 974 } 975 prsv = rsv->next; 976 memunmap(rsv); 977 } 978 979 /* no slot found - allocate a new linked list entry */ 980 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 981 if (!rsv) 982 return -ENOMEM; 983 984 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 985 if (rc) { 986 free_page((unsigned long)rsv); 987 return rc; 988 } 989 990 /* 991 * The memremap() call above assumes that a linux_efi_memreserve entry 992 * never crosses a page boundary, so let's ensure that this remains true 993 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 994 * using SZ_4K explicitly in the size calculation below. 995 */ 996 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 997 atomic_set(&rsv->count, 1); 998 rsv->entry[0].base = addr; 999 rsv->entry[0].size = size; 1000 1001 spin_lock(&efi_mem_reserve_persistent_lock); 1002 rsv->next = efi_memreserve_root->next; 1003 efi_memreserve_root->next = __pa(rsv); 1004 spin_unlock(&efi_mem_reserve_persistent_lock); 1005 1006 return efi_mem_reserve_iomem(addr, size); 1007 } 1008 1009 static int __init efi_memreserve_root_init(void) 1010 { 1011 if (efi_memreserve_root) 1012 return 0; 1013 if (efi_memreserve_map_root()) 1014 efi_memreserve_root = (void *)ULONG_MAX; 1015 return 0; 1016 } 1017 early_initcall(efi_memreserve_root_init); 1018 1019 #ifdef CONFIG_KEXEC 1020 static int update_efi_random_seed(struct notifier_block *nb, 1021 unsigned long code, void *unused) 1022 { 1023 struct linux_efi_random_seed *seed; 1024 u32 size = 0; 1025 1026 if (!kexec_in_progress) 1027 return NOTIFY_DONE; 1028 1029 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1030 if (seed != NULL) { 1031 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1032 memunmap(seed); 1033 } else { 1034 pr_err("Could not map UEFI random seed!\n"); 1035 } 1036 if (size > 0) { 1037 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1038 MEMREMAP_WB); 1039 if (seed != NULL) { 1040 seed->size = size; 1041 get_random_bytes(seed->bits, seed->size); 1042 memunmap(seed); 1043 } else { 1044 pr_err("Could not map UEFI random seed!\n"); 1045 } 1046 } 1047 return NOTIFY_DONE; 1048 } 1049 1050 static struct notifier_block efi_random_seed_nb = { 1051 .notifier_call = update_efi_random_seed, 1052 }; 1053 1054 static int __init register_update_efi_random_seed(void) 1055 { 1056 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1057 return 0; 1058 return register_reboot_notifier(&efi_random_seed_nb); 1059 } 1060 late_initcall(register_update_efi_random_seed); 1061 #endif 1062