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 16 206 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_iter(efi_char16_t *name, efi_guid_t vendor, 223 unsigned long name_size, void *data) 224 { 225 struct efivar_entry *entry; 226 struct list_head *list = data; 227 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 228 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size); 229 230 ucs2_as_utf8(utf8_name, name, limit - 1); 231 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 232 return 0; 233 234 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 235 if (!entry) 236 return 0; 237 238 memcpy(entry->var.VariableName, name, name_size); 239 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t)); 240 241 efivar_entry_add(entry, list); 242 243 return 0; 244 } 245 246 static __init int efivar_ssdt_load(void) 247 { 248 LIST_HEAD(entries); 249 struct efivar_entry *entry, *aux; 250 unsigned long size; 251 void *data; 252 int ret; 253 254 if (!efivar_ssdt[0]) 255 return 0; 256 257 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries); 258 259 list_for_each_entry_safe(entry, aux, &entries, list) { 260 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, 261 &entry->var.VendorGuid); 262 263 list_del(&entry->list); 264 265 ret = efivar_entry_size(entry, &size); 266 if (ret) { 267 pr_err("failed to get var size\n"); 268 goto free_entry; 269 } 270 271 data = kmalloc(size, GFP_KERNEL); 272 if (!data) { 273 ret = -ENOMEM; 274 goto free_entry; 275 } 276 277 ret = efivar_entry_get(entry, NULL, &size, data); 278 if (ret) { 279 pr_err("failed to get var data\n"); 280 goto free_data; 281 } 282 283 ret = acpi_load_table(data, NULL); 284 if (ret) { 285 pr_err("failed to load table: %d\n", ret); 286 goto free_data; 287 } 288 289 goto free_entry; 290 291 free_data: 292 kfree(data); 293 294 free_entry: 295 kfree(entry); 296 } 297 298 return ret; 299 } 300 #else 301 static inline int efivar_ssdt_load(void) { return 0; } 302 #endif 303 304 #ifdef CONFIG_DEBUG_FS 305 306 #define EFI_DEBUGFS_MAX_BLOBS 32 307 308 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; 309 310 static void __init efi_debugfs_init(void) 311 { 312 struct dentry *efi_debugfs; 313 efi_memory_desc_t *md; 314 char name[32]; 315 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; 316 int i = 0; 317 318 efi_debugfs = debugfs_create_dir("efi", NULL); 319 if (IS_ERR_OR_NULL(efi_debugfs)) 320 return; 321 322 for_each_efi_memory_desc(md) { 323 switch (md->type) { 324 case EFI_BOOT_SERVICES_CODE: 325 snprintf(name, sizeof(name), "boot_services_code%d", 326 type_count[md->type]++); 327 break; 328 case EFI_BOOT_SERVICES_DATA: 329 snprintf(name, sizeof(name), "boot_services_data%d", 330 type_count[md->type]++); 331 break; 332 default: 333 continue; 334 } 335 336 if (i >= EFI_DEBUGFS_MAX_BLOBS) { 337 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n", 338 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); 339 break; 340 } 341 342 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; 343 debugfs_blob[i].data = memremap(md->phys_addr, 344 debugfs_blob[i].size, 345 MEMREMAP_WB); 346 if (!debugfs_blob[i].data) 347 continue; 348 349 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); 350 i++; 351 } 352 } 353 #else 354 static inline void efi_debugfs_init(void) {} 355 #endif 356 357 /* 358 * We register the efi subsystem with the firmware subsystem and the 359 * efivars subsystem with the efi subsystem, if the system was booted with 360 * EFI. 361 */ 362 static int __init efisubsys_init(void) 363 { 364 int error; 365 366 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 367 efi.runtime_supported_mask = 0; 368 369 if (!efi_enabled(EFI_BOOT)) 370 return 0; 371 372 if (efi.runtime_supported_mask) { 373 /* 374 * Since we process only one efi_runtime_service() at a time, an 375 * ordered workqueue (which creates only one execution context) 376 * should suffice for all our needs. 377 */ 378 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 379 if (!efi_rts_wq) { 380 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 381 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 382 efi.runtime_supported_mask = 0; 383 return 0; 384 } 385 } 386 387 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES)) 388 platform_device_register_simple("rtc-efi", 0, NULL, 0); 389 390 /* We register the efi directory at /sys/firmware/efi */ 391 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 392 if (!efi_kobj) { 393 pr_err("efi: Firmware registration failed.\n"); 394 destroy_workqueue(efi_rts_wq); 395 return -ENOMEM; 396 } 397 398 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 399 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) { 400 error = generic_ops_register(); 401 if (error) 402 goto err_put; 403 efivar_ssdt_load(); 404 platform_device_register_simple("efivars", 0, NULL, 0); 405 } 406 407 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 408 if (error) { 409 pr_err("efi: Sysfs attribute export failed with error %d.\n", 410 error); 411 goto err_unregister; 412 } 413 414 error = efi_runtime_map_init(efi_kobj); 415 if (error) 416 goto err_remove_group; 417 418 /* and the standard mountpoint for efivarfs */ 419 error = sysfs_create_mount_point(efi_kobj, "efivars"); 420 if (error) { 421 pr_err("efivars: Subsystem registration failed.\n"); 422 goto err_remove_group; 423 } 424 425 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) 426 efi_debugfs_init(); 427 428 #ifdef CONFIG_EFI_COCO_SECRET 429 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR) 430 platform_device_register_simple("efi_secret", 0, NULL, 0); 431 #endif 432 433 return 0; 434 435 err_remove_group: 436 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 437 err_unregister: 438 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 439 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) 440 generic_ops_unregister(); 441 err_put: 442 kobject_put(efi_kobj); 443 destroy_workqueue(efi_rts_wq); 444 return error; 445 } 446 447 subsys_initcall(efisubsys_init); 448 449 /* 450 * Find the efi memory descriptor for a given physical address. Given a 451 * physical address, determine if it exists within an EFI Memory Map entry, 452 * and if so, populate the supplied memory descriptor with the appropriate 453 * data. 454 */ 455 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 456 { 457 efi_memory_desc_t *md; 458 459 if (!efi_enabled(EFI_MEMMAP)) { 460 pr_err_once("EFI_MEMMAP is not enabled.\n"); 461 return -EINVAL; 462 } 463 464 if (!out_md) { 465 pr_err_once("out_md is null.\n"); 466 return -EINVAL; 467 } 468 469 for_each_efi_memory_desc(md) { 470 u64 size; 471 u64 end; 472 473 size = md->num_pages << EFI_PAGE_SHIFT; 474 end = md->phys_addr + size; 475 if (phys_addr >= md->phys_addr && phys_addr < end) { 476 memcpy(out_md, md, sizeof(*out_md)); 477 return 0; 478 } 479 } 480 return -ENOENT; 481 } 482 483 /* 484 * Calculate the highest address of an efi memory descriptor. 485 */ 486 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 487 { 488 u64 size = md->num_pages << EFI_PAGE_SHIFT; 489 u64 end = md->phys_addr + size; 490 return end; 491 } 492 493 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 494 495 /** 496 * efi_mem_reserve - Reserve an EFI memory region 497 * @addr: Physical address to reserve 498 * @size: Size of reservation 499 * 500 * Mark a region as reserved from general kernel allocation and 501 * prevent it being released by efi_free_boot_services(). 502 * 503 * This function should be called drivers once they've parsed EFI 504 * configuration tables to figure out where their data lives, e.g. 505 * efi_esrt_init(). 506 */ 507 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 508 { 509 if (!memblock_is_region_reserved(addr, size)) 510 memblock_reserve(addr, size); 511 512 /* 513 * Some architectures (x86) reserve all boot services ranges 514 * until efi_free_boot_services() because of buggy firmware 515 * implementations. This means the above memblock_reserve() is 516 * superfluous on x86 and instead what it needs to do is 517 * ensure the @start, @size is not freed. 518 */ 519 efi_arch_mem_reserve(addr, size); 520 } 521 522 static const efi_config_table_type_t common_tables[] __initconst = { 523 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" }, 524 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" }, 525 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" }, 526 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" }, 527 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" }, 528 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" }, 529 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" }, 530 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" }, 531 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 532 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 533 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 534 #ifdef CONFIG_EFI_RCI2_TABLE 535 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 536 #endif 537 #ifdef CONFIG_LOAD_UEFI_KEYS 538 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 539 #endif 540 #ifdef CONFIG_EFI_COCO_SECRET 541 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 542 #endif 543 {}, 544 }; 545 546 static __init int match_config_table(const efi_guid_t *guid, 547 unsigned long table, 548 const efi_config_table_type_t *table_types) 549 { 550 int i; 551 552 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 553 if (!efi_guidcmp(*guid, table_types[i].guid)) { 554 *(table_types[i].ptr) = table; 555 if (table_types[i].name[0]) 556 pr_cont("%s=0x%lx ", 557 table_types[i].name, table); 558 return 1; 559 } 560 } 561 562 return 0; 563 } 564 565 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 566 int count, 567 const efi_config_table_type_t *arch_tables) 568 { 569 const efi_config_table_64_t *tbl64 = (void *)config_tables; 570 const efi_config_table_32_t *tbl32 = (void *)config_tables; 571 const efi_guid_t *guid; 572 unsigned long table; 573 int i; 574 575 pr_info(""); 576 for (i = 0; i < count; i++) { 577 if (!IS_ENABLED(CONFIG_X86)) { 578 guid = &config_tables[i].guid; 579 table = (unsigned long)config_tables[i].table; 580 } else if (efi_enabled(EFI_64BIT)) { 581 guid = &tbl64[i].guid; 582 table = tbl64[i].table; 583 584 if (IS_ENABLED(CONFIG_X86_32) && 585 tbl64[i].table > U32_MAX) { 586 pr_cont("\n"); 587 pr_err("Table located above 4GB, disabling EFI.\n"); 588 return -EINVAL; 589 } 590 } else { 591 guid = &tbl32[i].guid; 592 table = tbl32[i].table; 593 } 594 595 if (!match_config_table(guid, table, common_tables) && arch_tables) 596 match_config_table(guid, table, arch_tables); 597 } 598 pr_cont("\n"); 599 set_bit(EFI_CONFIG_TABLES, &efi.flags); 600 601 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 602 struct linux_efi_random_seed *seed; 603 u32 size = 0; 604 605 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 606 if (seed != NULL) { 607 size = READ_ONCE(seed->size); 608 early_memunmap(seed, sizeof(*seed)); 609 } else { 610 pr_err("Could not map UEFI random seed!\n"); 611 } 612 if (size > 0) { 613 seed = early_memremap(efi_rng_seed, 614 sizeof(*seed) + size); 615 if (seed != NULL) { 616 pr_notice("seeding entropy pool\n"); 617 add_bootloader_randomness(seed->bits, size); 618 early_memunmap(seed, sizeof(*seed) + size); 619 } else { 620 pr_err("Could not map UEFI random seed!\n"); 621 } 622 } 623 } 624 625 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 626 efi_memattr_init(); 627 628 efi_tpm_eventlog_init(); 629 630 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 631 unsigned long prsv = mem_reserve; 632 633 while (prsv) { 634 struct linux_efi_memreserve *rsv; 635 u8 *p; 636 637 /* 638 * Just map a full page: that is what we will get 639 * anyway, and it permits us to map the entire entry 640 * before knowing its size. 641 */ 642 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 643 PAGE_SIZE); 644 if (p == NULL) { 645 pr_err("Could not map UEFI memreserve entry!\n"); 646 return -ENOMEM; 647 } 648 649 rsv = (void *)(p + prsv % PAGE_SIZE); 650 651 /* reserve the entry itself */ 652 memblock_reserve(prsv, 653 struct_size(rsv, entry, rsv->size)); 654 655 for (i = 0; i < atomic_read(&rsv->count); i++) { 656 memblock_reserve(rsv->entry[i].base, 657 rsv->entry[i].size); 658 } 659 660 prsv = rsv->next; 661 early_memunmap(p, PAGE_SIZE); 662 } 663 } 664 665 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 666 efi_rt_properties_table_t *tbl; 667 668 tbl = early_memremap(rt_prop, sizeof(*tbl)); 669 if (tbl) { 670 efi.runtime_supported_mask &= tbl->runtime_services_supported; 671 early_memunmap(tbl, sizeof(*tbl)); 672 } 673 } 674 675 return 0; 676 } 677 678 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr, 679 int min_major_version) 680 { 681 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 682 pr_err("System table signature incorrect!\n"); 683 return -EINVAL; 684 } 685 686 if ((systab_hdr->revision >> 16) < min_major_version) 687 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n", 688 systab_hdr->revision >> 16, 689 systab_hdr->revision & 0xffff, 690 min_major_version); 691 692 return 0; 693 } 694 695 #ifndef CONFIG_IA64 696 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 697 size_t size) 698 { 699 const efi_char16_t *ret; 700 701 ret = early_memremap_ro(fw_vendor, size); 702 if (!ret) 703 pr_err("Could not map the firmware vendor!\n"); 704 return ret; 705 } 706 707 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 708 { 709 early_memunmap((void *)fw_vendor, size); 710 } 711 #else 712 #define map_fw_vendor(p, s) __va(p) 713 #define unmap_fw_vendor(v, s) 714 #endif 715 716 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 717 unsigned long fw_vendor) 718 { 719 char vendor[100] = "unknown"; 720 const efi_char16_t *c16; 721 size_t i; 722 723 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 724 if (c16) { 725 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 726 vendor[i] = c16[i]; 727 vendor[i] = '\0'; 728 729 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 730 } 731 732 pr_info("EFI v%u.%.02u by %s\n", 733 systab_hdr->revision >> 16, 734 systab_hdr->revision & 0xffff, 735 vendor); 736 737 if (IS_ENABLED(CONFIG_X86_64) && 738 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 739 !strcmp(vendor, "Apple")) { 740 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 741 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 742 } 743 } 744 745 static __initdata char memory_type_name[][13] = { 746 "Reserved", 747 "Loader Code", 748 "Loader Data", 749 "Boot Code", 750 "Boot Data", 751 "Runtime Code", 752 "Runtime Data", 753 "Conventional", 754 "Unusable", 755 "ACPI Reclaim", 756 "ACPI Mem NVS", 757 "MMIO", 758 "MMIO Port", 759 "PAL Code", 760 "Persistent", 761 }; 762 763 char * __init efi_md_typeattr_format(char *buf, size_t size, 764 const efi_memory_desc_t *md) 765 { 766 char *pos; 767 int type_len; 768 u64 attr; 769 770 pos = buf; 771 if (md->type >= ARRAY_SIZE(memory_type_name)) 772 type_len = snprintf(pos, size, "[type=%u", md->type); 773 else 774 type_len = snprintf(pos, size, "[%-*s", 775 (int)(sizeof(memory_type_name[0]) - 1), 776 memory_type_name[md->type]); 777 if (type_len >= size) 778 return buf; 779 780 pos += type_len; 781 size -= type_len; 782 783 attr = md->attribute; 784 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 785 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 786 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 787 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 788 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 789 snprintf(pos, size, "|attr=0x%016llx]", 790 (unsigned long long)attr); 791 else 792 snprintf(pos, size, 793 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 794 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 795 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 796 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 797 attr & EFI_MEMORY_SP ? "SP" : "", 798 attr & EFI_MEMORY_NV ? "NV" : "", 799 attr & EFI_MEMORY_XP ? "XP" : "", 800 attr & EFI_MEMORY_RP ? "RP" : "", 801 attr & EFI_MEMORY_WP ? "WP" : "", 802 attr & EFI_MEMORY_RO ? "RO" : "", 803 attr & EFI_MEMORY_UCE ? "UCE" : "", 804 attr & EFI_MEMORY_WB ? "WB" : "", 805 attr & EFI_MEMORY_WT ? "WT" : "", 806 attr & EFI_MEMORY_WC ? "WC" : "", 807 attr & EFI_MEMORY_UC ? "UC" : ""); 808 return buf; 809 } 810 811 /* 812 * IA64 has a funky EFI memory map that doesn't work the same way as 813 * other architectures. 814 */ 815 #ifndef CONFIG_IA64 816 /* 817 * efi_mem_attributes - lookup memmap attributes for physical address 818 * @phys_addr: the physical address to lookup 819 * 820 * Search in the EFI memory map for the region covering 821 * @phys_addr. Returns the EFI memory attributes if the region 822 * was found in the memory map, 0 otherwise. 823 */ 824 u64 efi_mem_attributes(unsigned long phys_addr) 825 { 826 efi_memory_desc_t *md; 827 828 if (!efi_enabled(EFI_MEMMAP)) 829 return 0; 830 831 for_each_efi_memory_desc(md) { 832 if ((md->phys_addr <= phys_addr) && 833 (phys_addr < (md->phys_addr + 834 (md->num_pages << EFI_PAGE_SHIFT)))) 835 return md->attribute; 836 } 837 return 0; 838 } 839 840 /* 841 * efi_mem_type - lookup memmap type for physical address 842 * @phys_addr: the physical address to lookup 843 * 844 * Search in the EFI memory map for the region covering @phys_addr. 845 * Returns the EFI memory type if the region was found in the memory 846 * map, -EINVAL otherwise. 847 */ 848 int efi_mem_type(unsigned long phys_addr) 849 { 850 const efi_memory_desc_t *md; 851 852 if (!efi_enabled(EFI_MEMMAP)) 853 return -ENOTSUPP; 854 855 for_each_efi_memory_desc(md) { 856 if ((md->phys_addr <= phys_addr) && 857 (phys_addr < (md->phys_addr + 858 (md->num_pages << EFI_PAGE_SHIFT)))) 859 return md->type; 860 } 861 return -EINVAL; 862 } 863 #endif 864 865 int efi_status_to_err(efi_status_t status) 866 { 867 int err; 868 869 switch (status) { 870 case EFI_SUCCESS: 871 err = 0; 872 break; 873 case EFI_INVALID_PARAMETER: 874 err = -EINVAL; 875 break; 876 case EFI_OUT_OF_RESOURCES: 877 err = -ENOSPC; 878 break; 879 case EFI_DEVICE_ERROR: 880 err = -EIO; 881 break; 882 case EFI_WRITE_PROTECTED: 883 err = -EROFS; 884 break; 885 case EFI_SECURITY_VIOLATION: 886 err = -EACCES; 887 break; 888 case EFI_NOT_FOUND: 889 err = -ENOENT; 890 break; 891 case EFI_ABORTED: 892 err = -EINTR; 893 break; 894 default: 895 err = -EINVAL; 896 } 897 898 return err; 899 } 900 901 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 902 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 903 904 static int __init efi_memreserve_map_root(void) 905 { 906 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 907 return -ENODEV; 908 909 efi_memreserve_root = memremap(mem_reserve, 910 sizeof(*efi_memreserve_root), 911 MEMREMAP_WB); 912 if (WARN_ON_ONCE(!efi_memreserve_root)) 913 return -ENOMEM; 914 return 0; 915 } 916 917 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 918 { 919 struct resource *res, *parent; 920 int ret; 921 922 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 923 if (!res) 924 return -ENOMEM; 925 926 res->name = "reserved"; 927 res->flags = IORESOURCE_MEM; 928 res->start = addr; 929 res->end = addr + size - 1; 930 931 /* we expect a conflict with a 'System RAM' region */ 932 parent = request_resource_conflict(&iomem_resource, res); 933 ret = parent ? request_resource(parent, res) : 0; 934 935 /* 936 * Given that efi_mem_reserve_iomem() can be called at any 937 * time, only call memblock_reserve() if the architecture 938 * keeps the infrastructure around. 939 */ 940 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 941 memblock_reserve(addr, size); 942 943 return ret; 944 } 945 946 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 947 { 948 struct linux_efi_memreserve *rsv; 949 unsigned long prsv; 950 int rc, index; 951 952 if (efi_memreserve_root == (void *)ULONG_MAX) 953 return -ENODEV; 954 955 if (!efi_memreserve_root) { 956 rc = efi_memreserve_map_root(); 957 if (rc) 958 return rc; 959 } 960 961 /* first try to find a slot in an existing linked list entry */ 962 for (prsv = efi_memreserve_root->next; prsv; ) { 963 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 964 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 965 if (index < rsv->size) { 966 rsv->entry[index].base = addr; 967 rsv->entry[index].size = size; 968 969 memunmap(rsv); 970 return efi_mem_reserve_iomem(addr, size); 971 } 972 prsv = rsv->next; 973 memunmap(rsv); 974 } 975 976 /* no slot found - allocate a new linked list entry */ 977 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 978 if (!rsv) 979 return -ENOMEM; 980 981 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 982 if (rc) { 983 free_page((unsigned long)rsv); 984 return rc; 985 } 986 987 /* 988 * The memremap() call above assumes that a linux_efi_memreserve entry 989 * never crosses a page boundary, so let's ensure that this remains true 990 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 991 * using SZ_4K explicitly in the size calculation below. 992 */ 993 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 994 atomic_set(&rsv->count, 1); 995 rsv->entry[0].base = addr; 996 rsv->entry[0].size = size; 997 998 spin_lock(&efi_mem_reserve_persistent_lock); 999 rsv->next = efi_memreserve_root->next; 1000 efi_memreserve_root->next = __pa(rsv); 1001 spin_unlock(&efi_mem_reserve_persistent_lock); 1002 1003 return efi_mem_reserve_iomem(addr, size); 1004 } 1005 1006 static int __init efi_memreserve_root_init(void) 1007 { 1008 if (efi_memreserve_root) 1009 return 0; 1010 if (efi_memreserve_map_root()) 1011 efi_memreserve_root = (void *)ULONG_MAX; 1012 return 0; 1013 } 1014 early_initcall(efi_memreserve_root_init); 1015 1016 #ifdef CONFIG_KEXEC 1017 static int update_efi_random_seed(struct notifier_block *nb, 1018 unsigned long code, void *unused) 1019 { 1020 struct linux_efi_random_seed *seed; 1021 u32 size = 0; 1022 1023 if (!kexec_in_progress) 1024 return NOTIFY_DONE; 1025 1026 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1027 if (seed != NULL) { 1028 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1029 memunmap(seed); 1030 } else { 1031 pr_err("Could not map UEFI random seed!\n"); 1032 } 1033 if (size > 0) { 1034 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1035 MEMREMAP_WB); 1036 if (seed != NULL) { 1037 seed->size = size; 1038 get_random_bytes(seed->bits, seed->size); 1039 memunmap(seed); 1040 } else { 1041 pr_err("Could not map UEFI random seed!\n"); 1042 } 1043 } 1044 return NOTIFY_DONE; 1045 } 1046 1047 static struct notifier_block efi_random_seed_nb = { 1048 .notifier_call = update_efi_random_seed, 1049 }; 1050 1051 static int __init register_update_efi_random_seed(void) 1052 { 1053 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1054 return 0; 1055 return register_reboot_notifier(&efi_random_seed_nb); 1056 } 1057 late_initcall(register_update_efi_random_seed); 1058 #endif 1059