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/initrd.h> 25 #include <linux/io.h> 26 #include <linux/kexec.h> 27 #include <linux/platform_device.h> 28 #include <linux/random.h> 29 #include <linux/reboot.h> 30 #include <linux/slab.h> 31 #include <linux/acpi.h> 32 #include <linux/ucs2_string.h> 33 #include <linux/memblock.h> 34 #include <linux/security.h> 35 36 #include <asm/early_ioremap.h> 37 38 struct efi __read_mostly efi = { 39 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL, 40 .acpi = EFI_INVALID_TABLE_ADDR, 41 .acpi20 = EFI_INVALID_TABLE_ADDR, 42 .smbios = EFI_INVALID_TABLE_ADDR, 43 .smbios3 = EFI_INVALID_TABLE_ADDR, 44 .esrt = EFI_INVALID_TABLE_ADDR, 45 .tpm_log = EFI_INVALID_TABLE_ADDR, 46 .tpm_final_log = EFI_INVALID_TABLE_ADDR, 47 #ifdef CONFIG_LOAD_UEFI_KEYS 48 .mokvar_table = EFI_INVALID_TABLE_ADDR, 49 #endif 50 #ifdef CONFIG_EFI_COCO_SECRET 51 .coco_secret = EFI_INVALID_TABLE_ADDR, 52 #endif 53 }; 54 EXPORT_SYMBOL(efi); 55 56 unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR; 57 static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; 58 static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR; 59 static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR; 60 61 struct mm_struct efi_mm = { 62 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock), 63 .mm_users = ATOMIC_INIT(2), 64 .mm_count = ATOMIC_INIT(1), 65 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq), 66 MMAP_LOCK_INITIALIZER(efi_mm) 67 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), 68 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), 69 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0}, 70 }; 71 72 struct workqueue_struct *efi_rts_wq; 73 74 static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME); 75 static int __init setup_noefi(char *arg) 76 { 77 disable_runtime = true; 78 return 0; 79 } 80 early_param("noefi", setup_noefi); 81 82 bool efi_runtime_disabled(void) 83 { 84 return disable_runtime; 85 } 86 87 bool __pure __efi_soft_reserve_enabled(void) 88 { 89 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE); 90 } 91 92 static int __init parse_efi_cmdline(char *str) 93 { 94 if (!str) { 95 pr_warn("need at least one option\n"); 96 return -EINVAL; 97 } 98 99 if (parse_option_str(str, "debug")) 100 set_bit(EFI_DBG, &efi.flags); 101 102 if (parse_option_str(str, "noruntime")) 103 disable_runtime = true; 104 105 if (parse_option_str(str, "runtime")) 106 disable_runtime = false; 107 108 if (parse_option_str(str, "nosoftreserve")) 109 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags); 110 111 return 0; 112 } 113 early_param("efi", parse_efi_cmdline); 114 115 struct kobject *efi_kobj; 116 117 /* 118 * Let's not leave out systab information that snuck into 119 * the efivars driver 120 * Note, do not add more fields in systab sysfs file as it breaks sysfs 121 * one value per file rule! 122 */ 123 static ssize_t systab_show(struct kobject *kobj, 124 struct kobj_attribute *attr, char *buf) 125 { 126 char *str = buf; 127 128 if (!kobj || !buf) 129 return -EINVAL; 130 131 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) 132 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); 133 if (efi.acpi != EFI_INVALID_TABLE_ADDR) 134 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); 135 /* 136 * If both SMBIOS and SMBIOS3 entry points are implemented, the 137 * SMBIOS3 entry point shall be preferred, so we list it first to 138 * let applications stop parsing after the first match. 139 */ 140 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) 141 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3); 142 if (efi.smbios != EFI_INVALID_TABLE_ADDR) 143 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); 144 145 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86)) 146 str = efi_systab_show_arch(str); 147 148 return str - buf; 149 } 150 151 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); 152 153 static ssize_t fw_platform_size_show(struct kobject *kobj, 154 struct kobj_attribute *attr, char *buf) 155 { 156 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); 157 } 158 159 extern __weak struct kobj_attribute efi_attr_fw_vendor; 160 extern __weak struct kobj_attribute efi_attr_runtime; 161 extern __weak struct kobj_attribute efi_attr_config_table; 162 static struct kobj_attribute efi_attr_fw_platform_size = 163 __ATTR_RO(fw_platform_size); 164 165 static struct attribute *efi_subsys_attrs[] = { 166 &efi_attr_systab.attr, 167 &efi_attr_fw_platform_size.attr, 168 &efi_attr_fw_vendor.attr, 169 &efi_attr_runtime.attr, 170 &efi_attr_config_table.attr, 171 NULL, 172 }; 173 174 umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, 175 int n) 176 { 177 return attr->mode; 178 } 179 180 static const struct attribute_group efi_subsys_attr_group = { 181 .attrs = efi_subsys_attrs, 182 .is_visible = efi_attr_is_visible, 183 }; 184 185 static struct efivars generic_efivars; 186 static struct efivar_operations generic_ops; 187 188 static int generic_ops_register(void) 189 { 190 generic_ops.get_variable = efi.get_variable; 191 generic_ops.get_next_variable = efi.get_next_variable; 192 generic_ops.query_variable_store = efi_query_variable_store; 193 194 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) { 195 generic_ops.set_variable = efi.set_variable; 196 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; 197 } 198 return efivars_register(&generic_efivars, &generic_ops, efi_kobj); 199 } 200 201 static void generic_ops_unregister(void) 202 { 203 efivars_unregister(&generic_efivars); 204 } 205 206 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS 207 #define EFIVAR_SSDT_NAME_MAX 16UL 208 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; 209 static int __init efivar_ssdt_setup(char *str) 210 { 211 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); 212 213 if (ret) 214 return ret; 215 216 if (strlen(str) < sizeof(efivar_ssdt)) 217 memcpy(efivar_ssdt, str, strlen(str)); 218 else 219 pr_warn("efivar_ssdt: name too long: %s\n", str); 220 return 1; 221 } 222 __setup("efivar_ssdt=", efivar_ssdt_setup); 223 224 static __init int efivar_ssdt_load(void) 225 { 226 unsigned long name_size = 256; 227 efi_char16_t *name = NULL; 228 efi_status_t status; 229 efi_guid_t guid; 230 231 if (!efivar_ssdt[0]) 232 return 0; 233 234 name = kzalloc(name_size, GFP_KERNEL); 235 if (!name) 236 return -ENOMEM; 237 238 for (;;) { 239 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 240 unsigned long data_size = 0; 241 void *data; 242 int limit; 243 244 status = efi.get_next_variable(&name_size, name, &guid); 245 if (status == EFI_NOT_FOUND) { 246 break; 247 } else if (status == EFI_BUFFER_TOO_SMALL) { 248 name = krealloc(name, name_size, GFP_KERNEL); 249 if (!name) 250 return -ENOMEM; 251 continue; 252 } 253 254 limit = min(EFIVAR_SSDT_NAME_MAX, name_size); 255 ucs2_as_utf8(utf8_name, name, limit - 1); 256 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 257 continue; 258 259 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid); 260 261 status = efi.get_variable(name, &guid, NULL, &data_size, NULL); 262 if (status != EFI_BUFFER_TOO_SMALL || !data_size) 263 return -EIO; 264 265 data = kmalloc(data_size, GFP_KERNEL); 266 if (!data) 267 return -ENOMEM; 268 269 status = efi.get_variable(name, &guid, NULL, &data_size, data); 270 if (status == EFI_SUCCESS) { 271 acpi_status ret = acpi_load_table(data, NULL); 272 if (ret) 273 pr_err("failed to load table: %u\n", ret); 274 } else { 275 pr_err("failed to get var data: 0x%lx\n", status); 276 } 277 kfree(data); 278 } 279 return 0; 280 } 281 #else 282 static inline int efivar_ssdt_load(void) { return 0; } 283 #endif 284 285 #ifdef CONFIG_DEBUG_FS 286 287 #define EFI_DEBUGFS_MAX_BLOBS 32 288 289 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; 290 291 static void __init efi_debugfs_init(void) 292 { 293 struct dentry *efi_debugfs; 294 efi_memory_desc_t *md; 295 char name[32]; 296 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; 297 int i = 0; 298 299 efi_debugfs = debugfs_create_dir("efi", NULL); 300 if (IS_ERR_OR_NULL(efi_debugfs)) 301 return; 302 303 for_each_efi_memory_desc(md) { 304 switch (md->type) { 305 case EFI_BOOT_SERVICES_CODE: 306 snprintf(name, sizeof(name), "boot_services_code%d", 307 type_count[md->type]++); 308 break; 309 case EFI_BOOT_SERVICES_DATA: 310 snprintf(name, sizeof(name), "boot_services_data%d", 311 type_count[md->type]++); 312 break; 313 default: 314 continue; 315 } 316 317 if (i >= EFI_DEBUGFS_MAX_BLOBS) { 318 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n", 319 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); 320 break; 321 } 322 323 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; 324 debugfs_blob[i].data = memremap(md->phys_addr, 325 debugfs_blob[i].size, 326 MEMREMAP_WB); 327 if (!debugfs_blob[i].data) 328 continue; 329 330 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); 331 i++; 332 } 333 } 334 #else 335 static inline void efi_debugfs_init(void) {} 336 #endif 337 338 /* 339 * We register the efi subsystem with the firmware subsystem and the 340 * efivars subsystem with the efi subsystem, if the system was booted with 341 * EFI. 342 */ 343 static int __init efisubsys_init(void) 344 { 345 int error; 346 347 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 348 efi.runtime_supported_mask = 0; 349 350 if (!efi_enabled(EFI_BOOT)) 351 return 0; 352 353 if (efi.runtime_supported_mask) { 354 /* 355 * Since we process only one efi_runtime_service() at a time, an 356 * ordered workqueue (which creates only one execution context) 357 * should suffice for all our needs. 358 */ 359 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 360 if (!efi_rts_wq) { 361 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 362 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 363 efi.runtime_supported_mask = 0; 364 return 0; 365 } 366 } 367 368 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES)) 369 platform_device_register_simple("rtc-efi", 0, NULL, 0); 370 371 /* We register the efi directory at /sys/firmware/efi */ 372 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 373 if (!efi_kobj) { 374 pr_err("efi: Firmware registration failed.\n"); 375 destroy_workqueue(efi_rts_wq); 376 return -ENOMEM; 377 } 378 379 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 380 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) { 381 error = generic_ops_register(); 382 if (error) 383 goto err_put; 384 efivar_ssdt_load(); 385 platform_device_register_simple("efivars", 0, NULL, 0); 386 } 387 388 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 389 if (error) { 390 pr_err("efi: Sysfs attribute export failed with error %d.\n", 391 error); 392 goto err_unregister; 393 } 394 395 error = efi_runtime_map_init(efi_kobj); 396 if (error) 397 goto err_remove_group; 398 399 /* and the standard mountpoint for efivarfs */ 400 error = sysfs_create_mount_point(efi_kobj, "efivars"); 401 if (error) { 402 pr_err("efivars: Subsystem registration failed.\n"); 403 goto err_remove_group; 404 } 405 406 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) 407 efi_debugfs_init(); 408 409 #ifdef CONFIG_EFI_COCO_SECRET 410 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR) 411 platform_device_register_simple("efi_secret", 0, NULL, 0); 412 #endif 413 414 return 0; 415 416 err_remove_group: 417 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 418 err_unregister: 419 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 420 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) 421 generic_ops_unregister(); 422 err_put: 423 kobject_put(efi_kobj); 424 destroy_workqueue(efi_rts_wq); 425 return error; 426 } 427 428 subsys_initcall(efisubsys_init); 429 430 void __init efi_find_mirror(void) 431 { 432 efi_memory_desc_t *md; 433 u64 mirror_size = 0, total_size = 0; 434 435 if (!efi_enabled(EFI_MEMMAP)) 436 return; 437 438 for_each_efi_memory_desc(md) { 439 unsigned long long start = md->phys_addr; 440 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT; 441 442 total_size += size; 443 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) { 444 memblock_mark_mirror(start, size); 445 mirror_size += size; 446 } 447 } 448 if (mirror_size) 449 pr_info("Memory: %lldM/%lldM mirrored memory\n", 450 mirror_size>>20, total_size>>20); 451 } 452 453 /* 454 * Find the efi memory descriptor for a given physical address. Given a 455 * physical address, determine if it exists within an EFI Memory Map entry, 456 * and if so, populate the supplied memory descriptor with the appropriate 457 * data. 458 */ 459 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 460 { 461 efi_memory_desc_t *md; 462 463 if (!efi_enabled(EFI_MEMMAP)) { 464 pr_err_once("EFI_MEMMAP is not enabled.\n"); 465 return -EINVAL; 466 } 467 468 if (!out_md) { 469 pr_err_once("out_md is null.\n"); 470 return -EINVAL; 471 } 472 473 for_each_efi_memory_desc(md) { 474 u64 size; 475 u64 end; 476 477 size = md->num_pages << EFI_PAGE_SHIFT; 478 end = md->phys_addr + size; 479 if (phys_addr >= md->phys_addr && phys_addr < end) { 480 memcpy(out_md, md, sizeof(*out_md)); 481 return 0; 482 } 483 } 484 return -ENOENT; 485 } 486 487 /* 488 * Calculate the highest address of an efi memory descriptor. 489 */ 490 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 491 { 492 u64 size = md->num_pages << EFI_PAGE_SHIFT; 493 u64 end = md->phys_addr + size; 494 return end; 495 } 496 497 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 498 499 /** 500 * efi_mem_reserve - Reserve an EFI memory region 501 * @addr: Physical address to reserve 502 * @size: Size of reservation 503 * 504 * Mark a region as reserved from general kernel allocation and 505 * prevent it being released by efi_free_boot_services(). 506 * 507 * This function should be called drivers once they've parsed EFI 508 * configuration tables to figure out where their data lives, e.g. 509 * efi_esrt_init(). 510 */ 511 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 512 { 513 if (!memblock_is_region_reserved(addr, size)) 514 memblock_reserve(addr, size); 515 516 /* 517 * Some architectures (x86) reserve all boot services ranges 518 * until efi_free_boot_services() because of buggy firmware 519 * implementations. This means the above memblock_reserve() is 520 * superfluous on x86 and instead what it needs to do is 521 * ensure the @start, @size is not freed. 522 */ 523 efi_arch_mem_reserve(addr, size); 524 } 525 526 static const efi_config_table_type_t common_tables[] __initconst = { 527 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" }, 528 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" }, 529 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" }, 530 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" }, 531 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" }, 532 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" }, 533 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" }, 534 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" }, 535 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 536 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 537 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" }, 538 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 539 #ifdef CONFIG_EFI_RCI2_TABLE 540 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 541 #endif 542 #ifdef CONFIG_LOAD_UEFI_KEYS 543 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 544 #endif 545 #ifdef CONFIG_EFI_COCO_SECRET 546 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 547 #endif 548 {}, 549 }; 550 551 static __init int match_config_table(const efi_guid_t *guid, 552 unsigned long table, 553 const efi_config_table_type_t *table_types) 554 { 555 int i; 556 557 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 558 if (!efi_guidcmp(*guid, table_types[i].guid)) { 559 *(table_types[i].ptr) = table; 560 if (table_types[i].name[0]) 561 pr_cont("%s=0x%lx ", 562 table_types[i].name, table); 563 return 1; 564 } 565 } 566 567 return 0; 568 } 569 570 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 571 int count, 572 const efi_config_table_type_t *arch_tables) 573 { 574 const efi_config_table_64_t *tbl64 = (void *)config_tables; 575 const efi_config_table_32_t *tbl32 = (void *)config_tables; 576 const efi_guid_t *guid; 577 unsigned long table; 578 int i; 579 580 pr_info(""); 581 for (i = 0; i < count; i++) { 582 if (!IS_ENABLED(CONFIG_X86)) { 583 guid = &config_tables[i].guid; 584 table = (unsigned long)config_tables[i].table; 585 } else if (efi_enabled(EFI_64BIT)) { 586 guid = &tbl64[i].guid; 587 table = tbl64[i].table; 588 589 if (IS_ENABLED(CONFIG_X86_32) && 590 tbl64[i].table > U32_MAX) { 591 pr_cont("\n"); 592 pr_err("Table located above 4GB, disabling EFI.\n"); 593 return -EINVAL; 594 } 595 } else { 596 guid = &tbl32[i].guid; 597 table = tbl32[i].table; 598 } 599 600 if (!match_config_table(guid, table, common_tables) && arch_tables) 601 match_config_table(guid, table, arch_tables); 602 } 603 pr_cont("\n"); 604 set_bit(EFI_CONFIG_TABLES, &efi.flags); 605 606 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 607 struct linux_efi_random_seed *seed; 608 u32 size = 0; 609 610 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 611 if (seed != NULL) { 612 size = READ_ONCE(seed->size); 613 early_memunmap(seed, sizeof(*seed)); 614 } else { 615 pr_err("Could not map UEFI random seed!\n"); 616 } 617 if (size > 0) { 618 seed = early_memremap(efi_rng_seed, 619 sizeof(*seed) + size); 620 if (seed != NULL) { 621 pr_notice("seeding entropy pool\n"); 622 add_bootloader_randomness(seed->bits, size); 623 early_memunmap(seed, sizeof(*seed) + size); 624 } else { 625 pr_err("Could not map UEFI random seed!\n"); 626 } 627 } 628 } 629 630 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 631 efi_memattr_init(); 632 633 efi_tpm_eventlog_init(); 634 635 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 636 unsigned long prsv = mem_reserve; 637 638 while (prsv) { 639 struct linux_efi_memreserve *rsv; 640 u8 *p; 641 642 /* 643 * Just map a full page: that is what we will get 644 * anyway, and it permits us to map the entire entry 645 * before knowing its size. 646 */ 647 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 648 PAGE_SIZE); 649 if (p == NULL) { 650 pr_err("Could not map UEFI memreserve entry!\n"); 651 return -ENOMEM; 652 } 653 654 rsv = (void *)(p + prsv % PAGE_SIZE); 655 656 /* reserve the entry itself */ 657 memblock_reserve(prsv, 658 struct_size(rsv, entry, rsv->size)); 659 660 for (i = 0; i < atomic_read(&rsv->count); i++) { 661 memblock_reserve(rsv->entry[i].base, 662 rsv->entry[i].size); 663 } 664 665 prsv = rsv->next; 666 early_memunmap(p, PAGE_SIZE); 667 } 668 } 669 670 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 671 efi_rt_properties_table_t *tbl; 672 673 tbl = early_memremap(rt_prop, sizeof(*tbl)); 674 if (tbl) { 675 efi.runtime_supported_mask &= tbl->runtime_services_supported; 676 early_memunmap(tbl, sizeof(*tbl)); 677 } 678 } 679 680 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && 681 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) { 682 struct linux_efi_initrd *tbl; 683 684 tbl = early_memremap(initrd, sizeof(*tbl)); 685 if (tbl) { 686 phys_initrd_start = tbl->base; 687 phys_initrd_size = tbl->size; 688 early_memunmap(tbl, sizeof(*tbl)); 689 } 690 } 691 692 return 0; 693 } 694 695 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr, 696 int min_major_version) 697 { 698 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 699 pr_err("System table signature incorrect!\n"); 700 return -EINVAL; 701 } 702 703 if ((systab_hdr->revision >> 16) < min_major_version) 704 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n", 705 systab_hdr->revision >> 16, 706 systab_hdr->revision & 0xffff, 707 min_major_version); 708 709 return 0; 710 } 711 712 #ifndef CONFIG_IA64 713 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 714 size_t size) 715 { 716 const efi_char16_t *ret; 717 718 ret = early_memremap_ro(fw_vendor, size); 719 if (!ret) 720 pr_err("Could not map the firmware vendor!\n"); 721 return ret; 722 } 723 724 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 725 { 726 early_memunmap((void *)fw_vendor, size); 727 } 728 #else 729 #define map_fw_vendor(p, s) __va(p) 730 #define unmap_fw_vendor(v, s) 731 #endif 732 733 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 734 unsigned long fw_vendor) 735 { 736 char vendor[100] = "unknown"; 737 const efi_char16_t *c16; 738 size_t i; 739 740 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 741 if (c16) { 742 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 743 vendor[i] = c16[i]; 744 vendor[i] = '\0'; 745 746 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 747 } 748 749 pr_info("EFI v%u.%.02u by %s\n", 750 systab_hdr->revision >> 16, 751 systab_hdr->revision & 0xffff, 752 vendor); 753 754 if (IS_ENABLED(CONFIG_X86_64) && 755 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 756 !strcmp(vendor, "Apple")) { 757 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 758 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 759 } 760 } 761 762 static __initdata char memory_type_name[][13] = { 763 "Reserved", 764 "Loader Code", 765 "Loader Data", 766 "Boot Code", 767 "Boot Data", 768 "Runtime Code", 769 "Runtime Data", 770 "Conventional", 771 "Unusable", 772 "ACPI Reclaim", 773 "ACPI Mem NVS", 774 "MMIO", 775 "MMIO Port", 776 "PAL Code", 777 "Persistent", 778 }; 779 780 char * __init efi_md_typeattr_format(char *buf, size_t size, 781 const efi_memory_desc_t *md) 782 { 783 char *pos; 784 int type_len; 785 u64 attr; 786 787 pos = buf; 788 if (md->type >= ARRAY_SIZE(memory_type_name)) 789 type_len = snprintf(pos, size, "[type=%u", md->type); 790 else 791 type_len = snprintf(pos, size, "[%-*s", 792 (int)(sizeof(memory_type_name[0]) - 1), 793 memory_type_name[md->type]); 794 if (type_len >= size) 795 return buf; 796 797 pos += type_len; 798 size -= type_len; 799 800 attr = md->attribute; 801 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 802 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 803 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 804 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 805 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 806 snprintf(pos, size, "|attr=0x%016llx]", 807 (unsigned long long)attr); 808 else 809 snprintf(pos, size, 810 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 811 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 812 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 813 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 814 attr & EFI_MEMORY_SP ? "SP" : "", 815 attr & EFI_MEMORY_NV ? "NV" : "", 816 attr & EFI_MEMORY_XP ? "XP" : "", 817 attr & EFI_MEMORY_RP ? "RP" : "", 818 attr & EFI_MEMORY_WP ? "WP" : "", 819 attr & EFI_MEMORY_RO ? "RO" : "", 820 attr & EFI_MEMORY_UCE ? "UCE" : "", 821 attr & EFI_MEMORY_WB ? "WB" : "", 822 attr & EFI_MEMORY_WT ? "WT" : "", 823 attr & EFI_MEMORY_WC ? "WC" : "", 824 attr & EFI_MEMORY_UC ? "UC" : ""); 825 return buf; 826 } 827 828 /* 829 * IA64 has a funky EFI memory map that doesn't work the same way as 830 * other architectures. 831 */ 832 #ifndef CONFIG_IA64 833 /* 834 * efi_mem_attributes - lookup memmap attributes for physical address 835 * @phys_addr: the physical address to lookup 836 * 837 * Search in the EFI memory map for the region covering 838 * @phys_addr. Returns the EFI memory attributes if the region 839 * was found in the memory map, 0 otherwise. 840 */ 841 u64 efi_mem_attributes(unsigned long phys_addr) 842 { 843 efi_memory_desc_t *md; 844 845 if (!efi_enabled(EFI_MEMMAP)) 846 return 0; 847 848 for_each_efi_memory_desc(md) { 849 if ((md->phys_addr <= phys_addr) && 850 (phys_addr < (md->phys_addr + 851 (md->num_pages << EFI_PAGE_SHIFT)))) 852 return md->attribute; 853 } 854 return 0; 855 } 856 857 /* 858 * efi_mem_type - lookup memmap type for physical address 859 * @phys_addr: the physical address to lookup 860 * 861 * Search in the EFI memory map for the region covering @phys_addr. 862 * Returns the EFI memory type if the region was found in the memory 863 * map, -EINVAL otherwise. 864 */ 865 int efi_mem_type(unsigned long phys_addr) 866 { 867 const efi_memory_desc_t *md; 868 869 if (!efi_enabled(EFI_MEMMAP)) 870 return -ENOTSUPP; 871 872 for_each_efi_memory_desc(md) { 873 if ((md->phys_addr <= phys_addr) && 874 (phys_addr < (md->phys_addr + 875 (md->num_pages << EFI_PAGE_SHIFT)))) 876 return md->type; 877 } 878 return -EINVAL; 879 } 880 #endif 881 882 int efi_status_to_err(efi_status_t status) 883 { 884 int err; 885 886 switch (status) { 887 case EFI_SUCCESS: 888 err = 0; 889 break; 890 case EFI_INVALID_PARAMETER: 891 err = -EINVAL; 892 break; 893 case EFI_OUT_OF_RESOURCES: 894 err = -ENOSPC; 895 break; 896 case EFI_DEVICE_ERROR: 897 err = -EIO; 898 break; 899 case EFI_WRITE_PROTECTED: 900 err = -EROFS; 901 break; 902 case EFI_SECURITY_VIOLATION: 903 err = -EACCES; 904 break; 905 case EFI_NOT_FOUND: 906 err = -ENOENT; 907 break; 908 case EFI_ABORTED: 909 err = -EINTR; 910 break; 911 default: 912 err = -EINVAL; 913 } 914 915 return err; 916 } 917 EXPORT_SYMBOL_GPL(efi_status_to_err); 918 919 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 920 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 921 922 static int __init efi_memreserve_map_root(void) 923 { 924 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 925 return -ENODEV; 926 927 efi_memreserve_root = memremap(mem_reserve, 928 sizeof(*efi_memreserve_root), 929 MEMREMAP_WB); 930 if (WARN_ON_ONCE(!efi_memreserve_root)) 931 return -ENOMEM; 932 return 0; 933 } 934 935 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 936 { 937 struct resource *res, *parent; 938 int ret; 939 940 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 941 if (!res) 942 return -ENOMEM; 943 944 res->name = "reserved"; 945 res->flags = IORESOURCE_MEM; 946 res->start = addr; 947 res->end = addr + size - 1; 948 949 /* we expect a conflict with a 'System RAM' region */ 950 parent = request_resource_conflict(&iomem_resource, res); 951 ret = parent ? request_resource(parent, res) : 0; 952 953 /* 954 * Given that efi_mem_reserve_iomem() can be called at any 955 * time, only call memblock_reserve() if the architecture 956 * keeps the infrastructure around. 957 */ 958 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 959 memblock_reserve(addr, size); 960 961 return ret; 962 } 963 964 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 965 { 966 struct linux_efi_memreserve *rsv; 967 unsigned long prsv; 968 int rc, index; 969 970 if (efi_memreserve_root == (void *)ULONG_MAX) 971 return -ENODEV; 972 973 if (!efi_memreserve_root) { 974 rc = efi_memreserve_map_root(); 975 if (rc) 976 return rc; 977 } 978 979 /* first try to find a slot in an existing linked list entry */ 980 for (prsv = efi_memreserve_root->next; prsv; ) { 981 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 982 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 983 if (index < rsv->size) { 984 rsv->entry[index].base = addr; 985 rsv->entry[index].size = size; 986 987 memunmap(rsv); 988 return efi_mem_reserve_iomem(addr, size); 989 } 990 prsv = rsv->next; 991 memunmap(rsv); 992 } 993 994 /* no slot found - allocate a new linked list entry */ 995 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 996 if (!rsv) 997 return -ENOMEM; 998 999 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 1000 if (rc) { 1001 free_page((unsigned long)rsv); 1002 return rc; 1003 } 1004 1005 /* 1006 * The memremap() call above assumes that a linux_efi_memreserve entry 1007 * never crosses a page boundary, so let's ensure that this remains true 1008 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 1009 * using SZ_4K explicitly in the size calculation below. 1010 */ 1011 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 1012 atomic_set(&rsv->count, 1); 1013 rsv->entry[0].base = addr; 1014 rsv->entry[0].size = size; 1015 1016 spin_lock(&efi_mem_reserve_persistent_lock); 1017 rsv->next = efi_memreserve_root->next; 1018 efi_memreserve_root->next = __pa(rsv); 1019 spin_unlock(&efi_mem_reserve_persistent_lock); 1020 1021 return efi_mem_reserve_iomem(addr, size); 1022 } 1023 1024 static int __init efi_memreserve_root_init(void) 1025 { 1026 if (efi_memreserve_root) 1027 return 0; 1028 if (efi_memreserve_map_root()) 1029 efi_memreserve_root = (void *)ULONG_MAX; 1030 return 0; 1031 } 1032 early_initcall(efi_memreserve_root_init); 1033 1034 #ifdef CONFIG_KEXEC 1035 static int update_efi_random_seed(struct notifier_block *nb, 1036 unsigned long code, void *unused) 1037 { 1038 struct linux_efi_random_seed *seed; 1039 u32 size = 0; 1040 1041 if (!kexec_in_progress) 1042 return NOTIFY_DONE; 1043 1044 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1045 if (seed != NULL) { 1046 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1047 memunmap(seed); 1048 } else { 1049 pr_err("Could not map UEFI random seed!\n"); 1050 } 1051 if (size > 0) { 1052 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1053 MEMREMAP_WB); 1054 if (seed != NULL) { 1055 seed->size = size; 1056 get_random_bytes(seed->bits, seed->size); 1057 memunmap(seed); 1058 } else { 1059 pr_err("Could not map UEFI random seed!\n"); 1060 } 1061 } 1062 return NOTIFY_DONE; 1063 } 1064 1065 static struct notifier_block efi_random_seed_nb = { 1066 .notifier_call = update_efi_random_seed, 1067 }; 1068 1069 static int __init register_update_efi_random_seed(void) 1070 { 1071 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1072 return 0; 1073 return register_reboot_notifier(&efi_random_seed_nb); 1074 } 1075 late_initcall(register_update_efi_random_seed); 1076 #endif 1077