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 #include <linux/notifier.h> 36 37 #include <asm/early_ioremap.h> 38 39 struct efi __read_mostly efi = { 40 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL, 41 .acpi = EFI_INVALID_TABLE_ADDR, 42 .acpi20 = EFI_INVALID_TABLE_ADDR, 43 .smbios = EFI_INVALID_TABLE_ADDR, 44 .smbios3 = EFI_INVALID_TABLE_ADDR, 45 .esrt = EFI_INVALID_TABLE_ADDR, 46 .tpm_log = EFI_INVALID_TABLE_ADDR, 47 .tpm_final_log = EFI_INVALID_TABLE_ADDR, 48 #ifdef CONFIG_LOAD_UEFI_KEYS 49 .mokvar_table = EFI_INVALID_TABLE_ADDR, 50 #endif 51 #ifdef CONFIG_EFI_COCO_SECRET 52 .coco_secret = EFI_INVALID_TABLE_ADDR, 53 #endif 54 #ifdef CONFIG_UNACCEPTED_MEMORY 55 .unaccepted = EFI_INVALID_TABLE_ADDR, 56 #endif 57 }; 58 EXPORT_SYMBOL(efi); 59 60 unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR; 61 static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; 62 static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR; 63 static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR; 64 65 extern unsigned long screen_info_table; 66 67 struct mm_struct efi_mm = { 68 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock), 69 .mm_users = ATOMIC_INIT(2), 70 .mm_count = ATOMIC_INIT(1), 71 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq), 72 MMAP_LOCK_INITIALIZER(efi_mm) 73 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), 74 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), 75 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0}, 76 }; 77 78 struct workqueue_struct *efi_rts_wq; 79 80 static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME); 81 static int __init setup_noefi(char *arg) 82 { 83 disable_runtime = true; 84 return 0; 85 } 86 early_param("noefi", setup_noefi); 87 88 bool efi_runtime_disabled(void) 89 { 90 return disable_runtime; 91 } 92 93 bool __pure __efi_soft_reserve_enabled(void) 94 { 95 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE); 96 } 97 98 static int __init parse_efi_cmdline(char *str) 99 { 100 if (!str) { 101 pr_warn("need at least one option\n"); 102 return -EINVAL; 103 } 104 105 if (parse_option_str(str, "debug")) 106 set_bit(EFI_DBG, &efi.flags); 107 108 if (parse_option_str(str, "noruntime")) 109 disable_runtime = true; 110 111 if (parse_option_str(str, "runtime")) 112 disable_runtime = false; 113 114 if (parse_option_str(str, "nosoftreserve")) 115 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags); 116 117 return 0; 118 } 119 early_param("efi", parse_efi_cmdline); 120 121 struct kobject *efi_kobj; 122 123 /* 124 * Let's not leave out systab information that snuck into 125 * the efivars driver 126 * Note, do not add more fields in systab sysfs file as it breaks sysfs 127 * one value per file rule! 128 */ 129 static ssize_t systab_show(struct kobject *kobj, 130 struct kobj_attribute *attr, char *buf) 131 { 132 char *str = buf; 133 134 if (!kobj || !buf) 135 return -EINVAL; 136 137 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) 138 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); 139 if (efi.acpi != EFI_INVALID_TABLE_ADDR) 140 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); 141 /* 142 * If both SMBIOS and SMBIOS3 entry points are implemented, the 143 * SMBIOS3 entry point shall be preferred, so we list it first to 144 * let applications stop parsing after the first match. 145 */ 146 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) 147 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3); 148 if (efi.smbios != EFI_INVALID_TABLE_ADDR) 149 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); 150 151 if (IS_ENABLED(CONFIG_X86)) 152 str = efi_systab_show_arch(str); 153 154 return str - buf; 155 } 156 157 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); 158 159 static ssize_t fw_platform_size_show(struct kobject *kobj, 160 struct kobj_attribute *attr, char *buf) 161 { 162 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); 163 } 164 165 extern __weak struct kobj_attribute efi_attr_fw_vendor; 166 extern __weak struct kobj_attribute efi_attr_runtime; 167 extern __weak struct kobj_attribute efi_attr_config_table; 168 static struct kobj_attribute efi_attr_fw_platform_size = 169 __ATTR_RO(fw_platform_size); 170 171 static struct attribute *efi_subsys_attrs[] = { 172 &efi_attr_systab.attr, 173 &efi_attr_fw_platform_size.attr, 174 &efi_attr_fw_vendor.attr, 175 &efi_attr_runtime.attr, 176 &efi_attr_config_table.attr, 177 NULL, 178 }; 179 180 umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, 181 int n) 182 { 183 return attr->mode; 184 } 185 186 static const struct attribute_group efi_subsys_attr_group = { 187 .attrs = efi_subsys_attrs, 188 .is_visible = efi_attr_is_visible, 189 }; 190 191 struct blocking_notifier_head efivar_ops_nh; 192 EXPORT_SYMBOL_GPL(efivar_ops_nh); 193 194 static struct efivars generic_efivars; 195 static struct efivar_operations generic_ops; 196 197 static bool generic_ops_supported(void) 198 { 199 unsigned long name_size; 200 efi_status_t status; 201 efi_char16_t name; 202 efi_guid_t guid; 203 204 name_size = sizeof(name); 205 206 status = efi.get_next_variable(&name_size, &name, &guid); 207 if (status == EFI_UNSUPPORTED) 208 return false; 209 210 return true; 211 } 212 213 static int generic_ops_register(void) 214 { 215 if (!generic_ops_supported()) 216 return 0; 217 218 generic_ops.get_variable = efi.get_variable; 219 generic_ops.get_next_variable = efi.get_next_variable; 220 generic_ops.query_variable_store = efi_query_variable_store; 221 generic_ops.query_variable_info = efi.query_variable_info; 222 223 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) { 224 generic_ops.set_variable = efi.set_variable; 225 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; 226 } 227 return efivars_register(&generic_efivars, &generic_ops); 228 } 229 230 static void generic_ops_unregister(void) 231 { 232 if (!generic_ops.get_variable) 233 return; 234 235 efivars_unregister(&generic_efivars); 236 } 237 238 void efivars_generic_ops_register(void) 239 { 240 generic_ops_register(); 241 } 242 EXPORT_SYMBOL_GPL(efivars_generic_ops_register); 243 244 void efivars_generic_ops_unregister(void) 245 { 246 generic_ops_unregister(); 247 } 248 EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister); 249 250 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS 251 #define EFIVAR_SSDT_NAME_MAX 16UL 252 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; 253 static int __init efivar_ssdt_setup(char *str) 254 { 255 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); 256 257 if (ret) 258 return ret; 259 260 if (strlen(str) < sizeof(efivar_ssdt)) 261 memcpy(efivar_ssdt, str, strlen(str)); 262 else 263 pr_warn("efivar_ssdt: name too long: %s\n", str); 264 return 1; 265 } 266 __setup("efivar_ssdt=", efivar_ssdt_setup); 267 268 static __init int efivar_ssdt_load(void) 269 { 270 unsigned long name_size = 256; 271 efi_char16_t *name = NULL; 272 efi_status_t status; 273 efi_guid_t guid; 274 275 if (!efivar_ssdt[0]) 276 return 0; 277 278 name = kzalloc(name_size, GFP_KERNEL); 279 if (!name) 280 return -ENOMEM; 281 282 for (;;) { 283 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 284 unsigned long data_size = 0; 285 void *data; 286 int limit; 287 288 status = efi.get_next_variable(&name_size, name, &guid); 289 if (status == EFI_NOT_FOUND) { 290 break; 291 } else if (status == EFI_BUFFER_TOO_SMALL) { 292 efi_char16_t *name_tmp = 293 krealloc(name, name_size, GFP_KERNEL); 294 if (!name_tmp) { 295 kfree(name); 296 return -ENOMEM; 297 } 298 name = name_tmp; 299 continue; 300 } 301 302 limit = min(EFIVAR_SSDT_NAME_MAX, name_size); 303 ucs2_as_utf8(utf8_name, name, limit - 1); 304 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 305 continue; 306 307 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid); 308 309 status = efi.get_variable(name, &guid, NULL, &data_size, NULL); 310 if (status != EFI_BUFFER_TOO_SMALL || !data_size) 311 return -EIO; 312 313 data = kmalloc(data_size, GFP_KERNEL); 314 if (!data) 315 return -ENOMEM; 316 317 status = efi.get_variable(name, &guid, NULL, &data_size, data); 318 if (status == EFI_SUCCESS) { 319 acpi_status ret = acpi_load_table(data, NULL); 320 if (ret) 321 pr_err("failed to load table: %u\n", ret); 322 else 323 continue; 324 } else { 325 pr_err("failed to get var data: 0x%lx\n", status); 326 } 327 kfree(data); 328 } 329 return 0; 330 } 331 #else 332 static inline int efivar_ssdt_load(void) { return 0; } 333 #endif 334 335 #ifdef CONFIG_DEBUG_FS 336 337 #define EFI_DEBUGFS_MAX_BLOBS 32 338 339 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; 340 341 static void __init efi_debugfs_init(void) 342 { 343 struct dentry *efi_debugfs; 344 efi_memory_desc_t *md; 345 char name[32]; 346 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; 347 int i = 0; 348 349 efi_debugfs = debugfs_create_dir("efi", NULL); 350 if (IS_ERR_OR_NULL(efi_debugfs)) 351 return; 352 353 for_each_efi_memory_desc(md) { 354 switch (md->type) { 355 case EFI_BOOT_SERVICES_CODE: 356 snprintf(name, sizeof(name), "boot_services_code%d", 357 type_count[md->type]++); 358 break; 359 case EFI_BOOT_SERVICES_DATA: 360 snprintf(name, sizeof(name), "boot_services_data%d", 361 type_count[md->type]++); 362 break; 363 default: 364 continue; 365 } 366 367 if (i >= EFI_DEBUGFS_MAX_BLOBS) { 368 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n", 369 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); 370 break; 371 } 372 373 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; 374 debugfs_blob[i].data = memremap(md->phys_addr, 375 debugfs_blob[i].size, 376 MEMREMAP_WB); 377 if (!debugfs_blob[i].data) 378 continue; 379 380 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); 381 i++; 382 } 383 } 384 #else 385 static inline void efi_debugfs_init(void) {} 386 #endif 387 388 /* 389 * We register the efi subsystem with the firmware subsystem and the 390 * efivars subsystem with the efi subsystem, if the system was booted with 391 * EFI. 392 */ 393 static int __init efisubsys_init(void) 394 { 395 int error; 396 397 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 398 efi.runtime_supported_mask = 0; 399 400 if (!efi_enabled(EFI_BOOT)) 401 return 0; 402 403 if (efi.runtime_supported_mask) { 404 /* 405 * Since we process only one efi_runtime_service() at a time, an 406 * ordered workqueue (which creates only one execution context) 407 * should suffice for all our needs. 408 */ 409 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 410 if (!efi_rts_wq) { 411 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 412 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 413 efi.runtime_supported_mask = 0; 414 return 0; 415 } 416 } 417 418 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES)) 419 platform_device_register_simple("rtc-efi", 0, NULL, 0); 420 421 /* We register the efi directory at /sys/firmware/efi */ 422 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 423 if (!efi_kobj) { 424 pr_err("efi: Firmware registration failed.\n"); 425 error = -ENOMEM; 426 goto err_destroy_wq; 427 } 428 429 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 430 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) { 431 error = generic_ops_register(); 432 if (error) 433 goto err_put; 434 efivar_ssdt_load(); 435 platform_device_register_simple("efivars", 0, NULL, 0); 436 } 437 438 BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh); 439 440 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 441 if (error) { 442 pr_err("efi: Sysfs attribute export failed with error %d.\n", 443 error); 444 goto err_unregister; 445 } 446 447 /* and the standard mountpoint for efivarfs */ 448 error = sysfs_create_mount_point(efi_kobj, "efivars"); 449 if (error) { 450 pr_err("efivars: Subsystem registration failed.\n"); 451 goto err_remove_group; 452 } 453 454 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) 455 efi_debugfs_init(); 456 457 #ifdef CONFIG_EFI_COCO_SECRET 458 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR) 459 platform_device_register_simple("efi_secret", 0, NULL, 0); 460 #endif 461 462 return 0; 463 464 err_remove_group: 465 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 466 err_unregister: 467 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 468 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) 469 generic_ops_unregister(); 470 err_put: 471 kobject_put(efi_kobj); 472 efi_kobj = NULL; 473 err_destroy_wq: 474 if (efi_rts_wq) 475 destroy_workqueue(efi_rts_wq); 476 477 return error; 478 } 479 480 subsys_initcall(efisubsys_init); 481 482 void __init efi_find_mirror(void) 483 { 484 efi_memory_desc_t *md; 485 u64 mirror_size = 0, total_size = 0; 486 487 if (!efi_enabled(EFI_MEMMAP)) 488 return; 489 490 for_each_efi_memory_desc(md) { 491 unsigned long long start = md->phys_addr; 492 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT; 493 494 total_size += size; 495 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) { 496 memblock_mark_mirror(start, size); 497 mirror_size += size; 498 } 499 } 500 if (mirror_size) 501 pr_info("Memory: %lldM/%lldM mirrored memory\n", 502 mirror_size>>20, total_size>>20); 503 } 504 505 /* 506 * Find the efi memory descriptor for a given physical address. Given a 507 * physical address, determine if it exists within an EFI Memory Map entry, 508 * and if so, populate the supplied memory descriptor with the appropriate 509 * data. 510 */ 511 int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 512 { 513 efi_memory_desc_t *md; 514 515 if (!efi_enabled(EFI_MEMMAP)) { 516 pr_err_once("EFI_MEMMAP is not enabled.\n"); 517 return -EINVAL; 518 } 519 520 if (!out_md) { 521 pr_err_once("out_md is null.\n"); 522 return -EINVAL; 523 } 524 525 for_each_efi_memory_desc(md) { 526 u64 size; 527 u64 end; 528 529 /* skip bogus entries (including empty ones) */ 530 if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) || 531 (md->num_pages <= 0) || 532 (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT)) 533 continue; 534 535 size = md->num_pages << EFI_PAGE_SHIFT; 536 end = md->phys_addr + size; 537 if (phys_addr >= md->phys_addr && phys_addr < end) { 538 memcpy(out_md, md, sizeof(*out_md)); 539 return 0; 540 } 541 } 542 return -ENOENT; 543 } 544 545 extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 546 __weak __alias(__efi_mem_desc_lookup); 547 548 /* 549 * Calculate the highest address of an efi memory descriptor. 550 */ 551 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 552 { 553 u64 size = md->num_pages << EFI_PAGE_SHIFT; 554 u64 end = md->phys_addr + size; 555 return end; 556 } 557 558 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 559 560 /** 561 * efi_mem_reserve - Reserve an EFI memory region 562 * @addr: Physical address to reserve 563 * @size: Size of reservation 564 * 565 * Mark a region as reserved from general kernel allocation and 566 * prevent it being released by efi_free_boot_services(). 567 * 568 * This function should be called drivers once they've parsed EFI 569 * configuration tables to figure out where their data lives, e.g. 570 * efi_esrt_init(). 571 */ 572 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 573 { 574 /* efi_mem_reserve() does not work under Xen */ 575 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT))) 576 return; 577 578 if (!memblock_is_region_reserved(addr, size)) 579 memblock_reserve(addr, size); 580 581 /* 582 * Some architectures (x86) reserve all boot services ranges 583 * until efi_free_boot_services() because of buggy firmware 584 * implementations. This means the above memblock_reserve() is 585 * superfluous on x86 and instead what it needs to do is 586 * ensure the @start, @size is not freed. 587 */ 588 efi_arch_mem_reserve(addr, size); 589 } 590 591 static const efi_config_table_type_t common_tables[] __initconst = { 592 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" }, 593 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" }, 594 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" }, 595 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" }, 596 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" }, 597 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" }, 598 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" }, 599 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" }, 600 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 601 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 602 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" }, 603 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 604 #ifdef CONFIG_EFI_RCI2_TABLE 605 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 606 #endif 607 #ifdef CONFIG_LOAD_UEFI_KEYS 608 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 609 #endif 610 #ifdef CONFIG_EFI_COCO_SECRET 611 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 612 #endif 613 #ifdef CONFIG_UNACCEPTED_MEMORY 614 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" }, 615 #endif 616 #ifdef CONFIG_EFI_GENERIC_STUB 617 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table }, 618 #endif 619 {}, 620 }; 621 622 static __init int match_config_table(const efi_guid_t *guid, 623 unsigned long table, 624 const efi_config_table_type_t *table_types) 625 { 626 int i; 627 628 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 629 if (efi_guidcmp(*guid, table_types[i].guid)) 630 continue; 631 632 if (!efi_config_table_is_usable(guid, table)) { 633 if (table_types[i].name[0]) 634 pr_cont("(%s=0x%lx unusable) ", 635 table_types[i].name, table); 636 return 1; 637 } 638 639 *(table_types[i].ptr) = table; 640 if (table_types[i].name[0]) 641 pr_cont("%s=0x%lx ", table_types[i].name, table); 642 return 1; 643 } 644 645 return 0; 646 } 647 648 /** 649 * reserve_unaccepted - Map and reserve unaccepted configuration table 650 * @unaccepted: Pointer to unaccepted memory table 651 * 652 * memblock_add() makes sure that the table is mapped in direct mapping. During 653 * normal boot it happens automatically because the table is allocated from 654 * usable memory. But during crashkernel boot only memory specifically reserved 655 * for crash scenario is mapped. memblock_add() forces the table to be mapped 656 * in crashkernel case. 657 * 658 * Align the range to the nearest page borders. Ranges smaller than page size 659 * are not going to be mapped. 660 * 661 * memblock_reserve() makes sure that future allocations will not touch the 662 * table. 663 */ 664 665 static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted) 666 { 667 phys_addr_t start, size; 668 669 start = PAGE_ALIGN_DOWN(efi.unaccepted); 670 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size); 671 672 memblock_add(start, size); 673 memblock_reserve(start, size); 674 } 675 676 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 677 int count, 678 const efi_config_table_type_t *arch_tables) 679 { 680 const efi_config_table_64_t *tbl64 = (void *)config_tables; 681 const efi_config_table_32_t *tbl32 = (void *)config_tables; 682 const efi_guid_t *guid; 683 unsigned long table; 684 int i; 685 686 pr_info(""); 687 for (i = 0; i < count; i++) { 688 if (!IS_ENABLED(CONFIG_X86)) { 689 guid = &config_tables[i].guid; 690 table = (unsigned long)config_tables[i].table; 691 } else if (efi_enabled(EFI_64BIT)) { 692 guid = &tbl64[i].guid; 693 table = tbl64[i].table; 694 695 if (IS_ENABLED(CONFIG_X86_32) && 696 tbl64[i].table > U32_MAX) { 697 pr_cont("\n"); 698 pr_err("Table located above 4GB, disabling EFI.\n"); 699 return -EINVAL; 700 } 701 } else { 702 guid = &tbl32[i].guid; 703 table = tbl32[i].table; 704 } 705 706 if (!match_config_table(guid, table, common_tables) && arch_tables) 707 match_config_table(guid, table, arch_tables); 708 } 709 pr_cont("\n"); 710 set_bit(EFI_CONFIG_TABLES, &efi.flags); 711 712 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 713 struct linux_efi_random_seed *seed; 714 u32 size = 0; 715 716 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 717 if (seed != NULL) { 718 size = min_t(u32, seed->size, SZ_1K); // sanity check 719 early_memunmap(seed, sizeof(*seed)); 720 } else { 721 pr_err("Could not map UEFI random seed!\n"); 722 } 723 if (size > 0) { 724 seed = early_memremap(efi_rng_seed, 725 sizeof(*seed) + size); 726 if (seed != NULL) { 727 add_bootloader_randomness(seed->bits, size); 728 memzero_explicit(seed->bits, size); 729 early_memunmap(seed, sizeof(*seed) + size); 730 } else { 731 pr_err("Could not map UEFI random seed!\n"); 732 } 733 } 734 } 735 736 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 737 efi_memattr_init(); 738 739 efi_tpm_eventlog_init(); 740 741 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 742 unsigned long prsv = mem_reserve; 743 744 while (prsv) { 745 struct linux_efi_memreserve *rsv; 746 u8 *p; 747 748 /* 749 * Just map a full page: that is what we will get 750 * anyway, and it permits us to map the entire entry 751 * before knowing its size. 752 */ 753 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 754 PAGE_SIZE); 755 if (p == NULL) { 756 pr_err("Could not map UEFI memreserve entry!\n"); 757 return -ENOMEM; 758 } 759 760 rsv = (void *)(p + prsv % PAGE_SIZE); 761 762 /* reserve the entry itself */ 763 memblock_reserve(prsv, 764 struct_size(rsv, entry, rsv->size)); 765 766 for (i = 0; i < atomic_read(&rsv->count); i++) { 767 memblock_reserve(rsv->entry[i].base, 768 rsv->entry[i].size); 769 } 770 771 prsv = rsv->next; 772 early_memunmap(p, PAGE_SIZE); 773 } 774 } 775 776 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 777 efi_rt_properties_table_t *tbl; 778 779 tbl = early_memremap(rt_prop, sizeof(*tbl)); 780 if (tbl) { 781 efi.runtime_supported_mask &= tbl->runtime_services_supported; 782 early_memunmap(tbl, sizeof(*tbl)); 783 } 784 } 785 786 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && 787 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) { 788 struct linux_efi_initrd *tbl; 789 790 tbl = early_memremap(initrd, sizeof(*tbl)); 791 if (tbl) { 792 phys_initrd_start = tbl->base; 793 phys_initrd_size = tbl->size; 794 early_memunmap(tbl, sizeof(*tbl)); 795 } 796 } 797 798 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && 799 efi.unaccepted != EFI_INVALID_TABLE_ADDR) { 800 struct efi_unaccepted_memory *unaccepted; 801 802 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted)); 803 if (unaccepted) { 804 805 if (unaccepted->version == 1) { 806 reserve_unaccepted(unaccepted); 807 } else { 808 efi.unaccepted = EFI_INVALID_TABLE_ADDR; 809 } 810 811 early_memunmap(unaccepted, sizeof(*unaccepted)); 812 } 813 } 814 815 return 0; 816 } 817 818 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr) 819 { 820 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 821 pr_err("System table signature incorrect!\n"); 822 return -EINVAL; 823 } 824 825 return 0; 826 } 827 828 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 829 size_t size) 830 { 831 const efi_char16_t *ret; 832 833 ret = early_memremap_ro(fw_vendor, size); 834 if (!ret) 835 pr_err("Could not map the firmware vendor!\n"); 836 return ret; 837 } 838 839 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 840 { 841 early_memunmap((void *)fw_vendor, size); 842 } 843 844 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 845 unsigned long fw_vendor) 846 { 847 char vendor[100] = "unknown"; 848 const efi_char16_t *c16; 849 size_t i; 850 u16 rev; 851 852 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 853 if (c16) { 854 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 855 vendor[i] = c16[i]; 856 vendor[i] = '\0'; 857 858 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 859 } 860 861 rev = (u16)systab_hdr->revision; 862 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10); 863 864 rev %= 10; 865 if (rev) 866 pr_cont(".%u", rev); 867 868 pr_cont(" by %s\n", vendor); 869 870 if (IS_ENABLED(CONFIG_X86_64) && 871 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 872 !strcmp(vendor, "Apple")) { 873 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 874 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 875 } 876 } 877 878 static __initdata char memory_type_name[][13] = { 879 "Reserved", 880 "Loader Code", 881 "Loader Data", 882 "Boot Code", 883 "Boot Data", 884 "Runtime Code", 885 "Runtime Data", 886 "Conventional", 887 "Unusable", 888 "ACPI Reclaim", 889 "ACPI Mem NVS", 890 "MMIO", 891 "MMIO Port", 892 "PAL Code", 893 "Persistent", 894 "Unaccepted", 895 }; 896 897 char * __init efi_md_typeattr_format(char *buf, size_t size, 898 const efi_memory_desc_t *md) 899 { 900 char *pos; 901 int type_len; 902 u64 attr; 903 904 pos = buf; 905 if (md->type >= ARRAY_SIZE(memory_type_name)) 906 type_len = snprintf(pos, size, "[type=%u", md->type); 907 else 908 type_len = snprintf(pos, size, "[%-*s", 909 (int)(sizeof(memory_type_name[0]) - 1), 910 memory_type_name[md->type]); 911 if (type_len >= size) 912 return buf; 913 914 pos += type_len; 915 size -= type_len; 916 917 attr = md->attribute; 918 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 919 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 920 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 921 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 922 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 923 snprintf(pos, size, "|attr=0x%016llx]", 924 (unsigned long long)attr); 925 else 926 snprintf(pos, size, 927 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 928 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 929 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 930 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 931 attr & EFI_MEMORY_SP ? "SP" : "", 932 attr & EFI_MEMORY_NV ? "NV" : "", 933 attr & EFI_MEMORY_XP ? "XP" : "", 934 attr & EFI_MEMORY_RP ? "RP" : "", 935 attr & EFI_MEMORY_WP ? "WP" : "", 936 attr & EFI_MEMORY_RO ? "RO" : "", 937 attr & EFI_MEMORY_UCE ? "UCE" : "", 938 attr & EFI_MEMORY_WB ? "WB" : "", 939 attr & EFI_MEMORY_WT ? "WT" : "", 940 attr & EFI_MEMORY_WC ? "WC" : "", 941 attr & EFI_MEMORY_UC ? "UC" : ""); 942 return buf; 943 } 944 945 /* 946 * efi_mem_attributes - lookup memmap attributes for physical address 947 * @phys_addr: the physical address to lookup 948 * 949 * Search in the EFI memory map for the region covering 950 * @phys_addr. Returns the EFI memory attributes if the region 951 * was found in the memory map, 0 otherwise. 952 */ 953 u64 efi_mem_attributes(unsigned long phys_addr) 954 { 955 efi_memory_desc_t *md; 956 957 if (!efi_enabled(EFI_MEMMAP)) 958 return 0; 959 960 for_each_efi_memory_desc(md) { 961 if ((md->phys_addr <= phys_addr) && 962 (phys_addr < (md->phys_addr + 963 (md->num_pages << EFI_PAGE_SHIFT)))) 964 return md->attribute; 965 } 966 return 0; 967 } 968 969 /* 970 * efi_mem_type - lookup memmap type for physical address 971 * @phys_addr: the physical address to lookup 972 * 973 * Search in the EFI memory map for the region covering @phys_addr. 974 * Returns the EFI memory type if the region was found in the memory 975 * map, -EINVAL otherwise. 976 */ 977 int efi_mem_type(unsigned long phys_addr) 978 { 979 const efi_memory_desc_t *md; 980 981 if (!efi_enabled(EFI_MEMMAP)) 982 return -ENOTSUPP; 983 984 for_each_efi_memory_desc(md) { 985 if ((md->phys_addr <= phys_addr) && 986 (phys_addr < (md->phys_addr + 987 (md->num_pages << EFI_PAGE_SHIFT)))) 988 return md->type; 989 } 990 return -EINVAL; 991 } 992 993 int efi_status_to_err(efi_status_t status) 994 { 995 int err; 996 997 switch (status) { 998 case EFI_SUCCESS: 999 err = 0; 1000 break; 1001 case EFI_INVALID_PARAMETER: 1002 err = -EINVAL; 1003 break; 1004 case EFI_OUT_OF_RESOURCES: 1005 err = -ENOSPC; 1006 break; 1007 case EFI_DEVICE_ERROR: 1008 err = -EIO; 1009 break; 1010 case EFI_WRITE_PROTECTED: 1011 err = -EROFS; 1012 break; 1013 case EFI_SECURITY_VIOLATION: 1014 err = -EACCES; 1015 break; 1016 case EFI_NOT_FOUND: 1017 err = -ENOENT; 1018 break; 1019 case EFI_ABORTED: 1020 err = -EINTR; 1021 break; 1022 default: 1023 err = -EINVAL; 1024 } 1025 1026 return err; 1027 } 1028 EXPORT_SYMBOL_GPL(efi_status_to_err); 1029 1030 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 1031 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 1032 1033 static int __init efi_memreserve_map_root(void) 1034 { 1035 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 1036 return -ENODEV; 1037 1038 efi_memreserve_root = memremap(mem_reserve, 1039 sizeof(*efi_memreserve_root), 1040 MEMREMAP_WB); 1041 if (WARN_ON_ONCE(!efi_memreserve_root)) 1042 return -ENOMEM; 1043 return 0; 1044 } 1045 1046 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 1047 { 1048 struct resource *res, *parent; 1049 int ret; 1050 1051 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 1052 if (!res) 1053 return -ENOMEM; 1054 1055 res->name = "reserved"; 1056 res->flags = IORESOURCE_MEM; 1057 res->start = addr; 1058 res->end = addr + size - 1; 1059 1060 /* we expect a conflict with a 'System RAM' region */ 1061 parent = request_resource_conflict(&iomem_resource, res); 1062 ret = parent ? request_resource(parent, res) : 0; 1063 1064 /* 1065 * Given that efi_mem_reserve_iomem() can be called at any 1066 * time, only call memblock_reserve() if the architecture 1067 * keeps the infrastructure around. 1068 */ 1069 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 1070 memblock_reserve(addr, size); 1071 1072 return ret; 1073 } 1074 1075 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 1076 { 1077 struct linux_efi_memreserve *rsv; 1078 unsigned long prsv; 1079 int rc, index; 1080 1081 if (efi_memreserve_root == (void *)ULONG_MAX) 1082 return -ENODEV; 1083 1084 if (!efi_memreserve_root) { 1085 rc = efi_memreserve_map_root(); 1086 if (rc) 1087 return rc; 1088 } 1089 1090 /* first try to find a slot in an existing linked list entry */ 1091 for (prsv = efi_memreserve_root->next; prsv; ) { 1092 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 1093 if (!rsv) 1094 return -ENOMEM; 1095 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 1096 if (index < rsv->size) { 1097 rsv->entry[index].base = addr; 1098 rsv->entry[index].size = size; 1099 1100 memunmap(rsv); 1101 return efi_mem_reserve_iomem(addr, size); 1102 } 1103 prsv = rsv->next; 1104 memunmap(rsv); 1105 } 1106 1107 /* no slot found - allocate a new linked list entry */ 1108 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 1109 if (!rsv) 1110 return -ENOMEM; 1111 1112 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 1113 if (rc) { 1114 free_page((unsigned long)rsv); 1115 return rc; 1116 } 1117 1118 /* 1119 * The memremap() call above assumes that a linux_efi_memreserve entry 1120 * never crosses a page boundary, so let's ensure that this remains true 1121 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 1122 * using SZ_4K explicitly in the size calculation below. 1123 */ 1124 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 1125 atomic_set(&rsv->count, 1); 1126 rsv->entry[0].base = addr; 1127 rsv->entry[0].size = size; 1128 1129 spin_lock(&efi_mem_reserve_persistent_lock); 1130 rsv->next = efi_memreserve_root->next; 1131 efi_memreserve_root->next = __pa(rsv); 1132 spin_unlock(&efi_mem_reserve_persistent_lock); 1133 1134 return efi_mem_reserve_iomem(addr, size); 1135 } 1136 1137 static int __init efi_memreserve_root_init(void) 1138 { 1139 if (efi_memreserve_root) 1140 return 0; 1141 if (efi_memreserve_map_root()) 1142 efi_memreserve_root = (void *)ULONG_MAX; 1143 return 0; 1144 } 1145 early_initcall(efi_memreserve_root_init); 1146 1147 #ifdef CONFIG_KEXEC 1148 static int update_efi_random_seed(struct notifier_block *nb, 1149 unsigned long code, void *unused) 1150 { 1151 struct linux_efi_random_seed *seed; 1152 u32 size = 0; 1153 1154 if (!kexec_in_progress) 1155 return NOTIFY_DONE; 1156 1157 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1158 if (seed != NULL) { 1159 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1160 memunmap(seed); 1161 } else { 1162 pr_err("Could not map UEFI random seed!\n"); 1163 } 1164 if (size > 0) { 1165 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1166 MEMREMAP_WB); 1167 if (seed != NULL) { 1168 seed->size = size; 1169 get_random_bytes(seed->bits, seed->size); 1170 memunmap(seed); 1171 } else { 1172 pr_err("Could not map UEFI random seed!\n"); 1173 } 1174 } 1175 return NOTIFY_DONE; 1176 } 1177 1178 static struct notifier_block efi_random_seed_nb = { 1179 .notifier_call = update_efi_random_seed, 1180 }; 1181 1182 static int __init register_update_efi_random_seed(void) 1183 { 1184 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1185 return 0; 1186 return register_reboot_notifier(&efi_random_seed_nb); 1187 } 1188 late_initcall(register_update_efi_random_seed); 1189 #endif 1190