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 {EFI_TCG2_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 601 {EFI_CC_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "CCFinalLog" }, 602 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 603 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" }, 604 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 605 #ifdef CONFIG_EFI_RCI2_TABLE 606 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 607 #endif 608 #ifdef CONFIG_LOAD_UEFI_KEYS 609 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 610 #endif 611 #ifdef CONFIG_EFI_COCO_SECRET 612 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 613 #endif 614 #ifdef CONFIG_UNACCEPTED_MEMORY 615 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" }, 616 #endif 617 #ifdef CONFIG_EFI_GENERIC_STUB 618 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table }, 619 #endif 620 {}, 621 }; 622 623 static __init int match_config_table(const efi_guid_t *guid, 624 unsigned long table, 625 const efi_config_table_type_t *table_types) 626 { 627 int i; 628 629 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 630 if (efi_guidcmp(*guid, table_types[i].guid)) 631 continue; 632 633 if (!efi_config_table_is_usable(guid, table)) { 634 if (table_types[i].name[0]) 635 pr_cont("(%s=0x%lx unusable) ", 636 table_types[i].name, table); 637 return 1; 638 } 639 640 *(table_types[i].ptr) = table; 641 if (table_types[i].name[0]) 642 pr_cont("%s=0x%lx ", table_types[i].name, table); 643 return 1; 644 } 645 646 return 0; 647 } 648 649 /** 650 * reserve_unaccepted - Map and reserve unaccepted configuration table 651 * @unaccepted: Pointer to unaccepted memory table 652 * 653 * memblock_add() makes sure that the table is mapped in direct mapping. During 654 * normal boot it happens automatically because the table is allocated from 655 * usable memory. But during crashkernel boot only memory specifically reserved 656 * for crash scenario is mapped. memblock_add() forces the table to be mapped 657 * in crashkernel case. 658 * 659 * Align the range to the nearest page borders. Ranges smaller than page size 660 * are not going to be mapped. 661 * 662 * memblock_reserve() makes sure that future allocations will not touch the 663 * table. 664 */ 665 666 static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted) 667 { 668 phys_addr_t start, size; 669 670 start = PAGE_ALIGN_DOWN(efi.unaccepted); 671 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size); 672 673 memblock_add(start, size); 674 memblock_reserve(start, size); 675 } 676 677 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 678 int count, 679 const efi_config_table_type_t *arch_tables) 680 { 681 const efi_config_table_64_t *tbl64 = (void *)config_tables; 682 const efi_config_table_32_t *tbl32 = (void *)config_tables; 683 const efi_guid_t *guid; 684 unsigned long table; 685 int i; 686 687 pr_info(""); 688 for (i = 0; i < count; i++) { 689 if (!IS_ENABLED(CONFIG_X86)) { 690 guid = &config_tables[i].guid; 691 table = (unsigned long)config_tables[i].table; 692 } else if (efi_enabled(EFI_64BIT)) { 693 guid = &tbl64[i].guid; 694 table = tbl64[i].table; 695 696 if (IS_ENABLED(CONFIG_X86_32) && 697 tbl64[i].table > U32_MAX) { 698 pr_cont("\n"); 699 pr_err("Table located above 4GB, disabling EFI.\n"); 700 return -EINVAL; 701 } 702 } else { 703 guid = &tbl32[i].guid; 704 table = tbl32[i].table; 705 } 706 707 if (!match_config_table(guid, table, common_tables) && arch_tables) 708 match_config_table(guid, table, arch_tables); 709 } 710 pr_cont("\n"); 711 set_bit(EFI_CONFIG_TABLES, &efi.flags); 712 713 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 714 struct linux_efi_random_seed *seed; 715 u32 size = 0; 716 717 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 718 if (seed != NULL) { 719 size = min_t(u32, seed->size, SZ_1K); // sanity check 720 early_memunmap(seed, sizeof(*seed)); 721 } else { 722 pr_err("Could not map UEFI random seed!\n"); 723 } 724 if (size > 0) { 725 seed = early_memremap(efi_rng_seed, 726 sizeof(*seed) + size); 727 if (seed != NULL) { 728 add_bootloader_randomness(seed->bits, size); 729 memzero_explicit(seed->bits, size); 730 early_memunmap(seed, sizeof(*seed) + size); 731 } else { 732 pr_err("Could not map UEFI random seed!\n"); 733 } 734 } 735 } 736 737 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 738 efi_memattr_init(); 739 740 efi_tpm_eventlog_init(); 741 742 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 743 unsigned long prsv = mem_reserve; 744 745 while (prsv) { 746 struct linux_efi_memreserve *rsv; 747 u8 *p; 748 749 /* 750 * Just map a full page: that is what we will get 751 * anyway, and it permits us to map the entire entry 752 * before knowing its size. 753 */ 754 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 755 PAGE_SIZE); 756 if (p == NULL) { 757 pr_err("Could not map UEFI memreserve entry!\n"); 758 return -ENOMEM; 759 } 760 761 rsv = (void *)(p + prsv % PAGE_SIZE); 762 763 /* reserve the entry itself */ 764 memblock_reserve(prsv, 765 struct_size(rsv, entry, rsv->size)); 766 767 for (i = 0; i < atomic_read(&rsv->count); i++) { 768 memblock_reserve(rsv->entry[i].base, 769 rsv->entry[i].size); 770 } 771 772 prsv = rsv->next; 773 early_memunmap(p, PAGE_SIZE); 774 } 775 } 776 777 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 778 efi_rt_properties_table_t *tbl; 779 780 tbl = early_memremap(rt_prop, sizeof(*tbl)); 781 if (tbl) { 782 efi.runtime_supported_mask &= tbl->runtime_services_supported; 783 early_memunmap(tbl, sizeof(*tbl)); 784 } 785 } 786 787 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && 788 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) { 789 struct linux_efi_initrd *tbl; 790 791 tbl = early_memremap(initrd, sizeof(*tbl)); 792 if (tbl) { 793 phys_initrd_start = tbl->base; 794 phys_initrd_size = tbl->size; 795 early_memunmap(tbl, sizeof(*tbl)); 796 } 797 } 798 799 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && 800 efi.unaccepted != EFI_INVALID_TABLE_ADDR) { 801 struct efi_unaccepted_memory *unaccepted; 802 803 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted)); 804 if (unaccepted) { 805 806 if (unaccepted->version == 1) { 807 reserve_unaccepted(unaccepted); 808 } else { 809 efi.unaccepted = EFI_INVALID_TABLE_ADDR; 810 } 811 812 early_memunmap(unaccepted, sizeof(*unaccepted)); 813 } 814 } 815 816 return 0; 817 } 818 819 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr) 820 { 821 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 822 pr_err("System table signature incorrect!\n"); 823 return -EINVAL; 824 } 825 826 return 0; 827 } 828 829 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 830 size_t size) 831 { 832 const efi_char16_t *ret; 833 834 ret = early_memremap_ro(fw_vendor, size); 835 if (!ret) 836 pr_err("Could not map the firmware vendor!\n"); 837 return ret; 838 } 839 840 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 841 { 842 early_memunmap((void *)fw_vendor, size); 843 } 844 845 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 846 unsigned long fw_vendor) 847 { 848 char vendor[100] = "unknown"; 849 const efi_char16_t *c16; 850 size_t i; 851 u16 rev; 852 853 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 854 if (c16) { 855 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 856 vendor[i] = c16[i]; 857 vendor[i] = '\0'; 858 859 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 860 } 861 862 rev = (u16)systab_hdr->revision; 863 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10); 864 865 rev %= 10; 866 if (rev) 867 pr_cont(".%u", rev); 868 869 pr_cont(" by %s\n", vendor); 870 871 if (IS_ENABLED(CONFIG_X86_64) && 872 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 873 !strcmp(vendor, "Apple")) { 874 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 875 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 876 } 877 } 878 879 static __initdata char memory_type_name[][13] = { 880 "Reserved", 881 "Loader Code", 882 "Loader Data", 883 "Boot Code", 884 "Boot Data", 885 "Runtime Code", 886 "Runtime Data", 887 "Conventional", 888 "Unusable", 889 "ACPI Reclaim", 890 "ACPI Mem NVS", 891 "MMIO", 892 "MMIO Port", 893 "PAL Code", 894 "Persistent", 895 "Unaccepted", 896 }; 897 898 char * __init efi_md_typeattr_format(char *buf, size_t size, 899 const efi_memory_desc_t *md) 900 { 901 char *pos; 902 int type_len; 903 u64 attr; 904 905 pos = buf; 906 if (md->type >= ARRAY_SIZE(memory_type_name)) 907 type_len = snprintf(pos, size, "[type=%u", md->type); 908 else 909 type_len = snprintf(pos, size, "[%-*s", 910 (int)(sizeof(memory_type_name[0]) - 1), 911 memory_type_name[md->type]); 912 if (type_len >= size) 913 return buf; 914 915 pos += type_len; 916 size -= type_len; 917 918 attr = md->attribute; 919 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 920 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 921 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 922 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 923 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 924 snprintf(pos, size, "|attr=0x%016llx]", 925 (unsigned long long)attr); 926 else 927 snprintf(pos, size, 928 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 929 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 930 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 931 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 932 attr & EFI_MEMORY_SP ? "SP" : "", 933 attr & EFI_MEMORY_NV ? "NV" : "", 934 attr & EFI_MEMORY_XP ? "XP" : "", 935 attr & EFI_MEMORY_RP ? "RP" : "", 936 attr & EFI_MEMORY_WP ? "WP" : "", 937 attr & EFI_MEMORY_RO ? "RO" : "", 938 attr & EFI_MEMORY_UCE ? "UCE" : "", 939 attr & EFI_MEMORY_WB ? "WB" : "", 940 attr & EFI_MEMORY_WT ? "WT" : "", 941 attr & EFI_MEMORY_WC ? "WC" : "", 942 attr & EFI_MEMORY_UC ? "UC" : ""); 943 return buf; 944 } 945 946 /* 947 * efi_mem_attributes - lookup memmap attributes for physical address 948 * @phys_addr: the physical address to lookup 949 * 950 * Search in the EFI memory map for the region covering 951 * @phys_addr. Returns the EFI memory attributes if the region 952 * was found in the memory map, 0 otherwise. 953 */ 954 u64 efi_mem_attributes(unsigned long phys_addr) 955 { 956 efi_memory_desc_t *md; 957 958 if (!efi_enabled(EFI_MEMMAP)) 959 return 0; 960 961 for_each_efi_memory_desc(md) { 962 if ((md->phys_addr <= phys_addr) && 963 (phys_addr < (md->phys_addr + 964 (md->num_pages << EFI_PAGE_SHIFT)))) 965 return md->attribute; 966 } 967 return 0; 968 } 969 970 /* 971 * efi_mem_type - lookup memmap type for physical address 972 * @phys_addr: the physical address to lookup 973 * 974 * Search in the EFI memory map for the region covering @phys_addr. 975 * Returns the EFI memory type if the region was found in the memory 976 * map, -EINVAL otherwise. 977 */ 978 int efi_mem_type(unsigned long phys_addr) 979 { 980 const efi_memory_desc_t *md; 981 982 if (!efi_enabled(EFI_MEMMAP)) 983 return -ENOTSUPP; 984 985 for_each_efi_memory_desc(md) { 986 if ((md->phys_addr <= phys_addr) && 987 (phys_addr < (md->phys_addr + 988 (md->num_pages << EFI_PAGE_SHIFT)))) 989 return md->type; 990 } 991 return -EINVAL; 992 } 993 994 int efi_status_to_err(efi_status_t status) 995 { 996 int err; 997 998 switch (status) { 999 case EFI_SUCCESS: 1000 err = 0; 1001 break; 1002 case EFI_INVALID_PARAMETER: 1003 err = -EINVAL; 1004 break; 1005 case EFI_OUT_OF_RESOURCES: 1006 err = -ENOSPC; 1007 break; 1008 case EFI_DEVICE_ERROR: 1009 err = -EIO; 1010 break; 1011 case EFI_WRITE_PROTECTED: 1012 err = -EROFS; 1013 break; 1014 case EFI_SECURITY_VIOLATION: 1015 err = -EACCES; 1016 break; 1017 case EFI_NOT_FOUND: 1018 err = -ENOENT; 1019 break; 1020 case EFI_ABORTED: 1021 err = -EINTR; 1022 break; 1023 default: 1024 err = -EINVAL; 1025 } 1026 1027 return err; 1028 } 1029 EXPORT_SYMBOL_GPL(efi_status_to_err); 1030 1031 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 1032 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 1033 1034 static int __init efi_memreserve_map_root(void) 1035 { 1036 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 1037 return -ENODEV; 1038 1039 efi_memreserve_root = memremap(mem_reserve, 1040 sizeof(*efi_memreserve_root), 1041 MEMREMAP_WB); 1042 if (WARN_ON_ONCE(!efi_memreserve_root)) 1043 return -ENOMEM; 1044 return 0; 1045 } 1046 1047 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 1048 { 1049 struct resource *res, *parent; 1050 int ret; 1051 1052 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 1053 if (!res) 1054 return -ENOMEM; 1055 1056 res->name = "reserved"; 1057 res->flags = IORESOURCE_MEM; 1058 res->start = addr; 1059 res->end = addr + size - 1; 1060 1061 /* we expect a conflict with a 'System RAM' region */ 1062 parent = request_resource_conflict(&iomem_resource, res); 1063 ret = parent ? request_resource(parent, res) : 0; 1064 1065 /* 1066 * Given that efi_mem_reserve_iomem() can be called at any 1067 * time, only call memblock_reserve() if the architecture 1068 * keeps the infrastructure around. 1069 */ 1070 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 1071 memblock_reserve(addr, size); 1072 1073 return ret; 1074 } 1075 1076 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 1077 { 1078 struct linux_efi_memreserve *rsv; 1079 unsigned long prsv; 1080 int rc, index; 1081 1082 if (efi_memreserve_root == (void *)ULONG_MAX) 1083 return -ENODEV; 1084 1085 if (!efi_memreserve_root) { 1086 rc = efi_memreserve_map_root(); 1087 if (rc) 1088 return rc; 1089 } 1090 1091 /* first try to find a slot in an existing linked list entry */ 1092 for (prsv = efi_memreserve_root->next; prsv; ) { 1093 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 1094 if (!rsv) 1095 return -ENOMEM; 1096 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 1097 if (index < rsv->size) { 1098 rsv->entry[index].base = addr; 1099 rsv->entry[index].size = size; 1100 1101 memunmap(rsv); 1102 return efi_mem_reserve_iomem(addr, size); 1103 } 1104 prsv = rsv->next; 1105 memunmap(rsv); 1106 } 1107 1108 /* no slot found - allocate a new linked list entry */ 1109 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 1110 if (!rsv) 1111 return -ENOMEM; 1112 1113 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 1114 if (rc) { 1115 free_page((unsigned long)rsv); 1116 return rc; 1117 } 1118 1119 /* 1120 * The memremap() call above assumes that a linux_efi_memreserve entry 1121 * never crosses a page boundary, so let's ensure that this remains true 1122 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 1123 * using SZ_4K explicitly in the size calculation below. 1124 */ 1125 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 1126 atomic_set(&rsv->count, 1); 1127 rsv->entry[0].base = addr; 1128 rsv->entry[0].size = size; 1129 1130 spin_lock(&efi_mem_reserve_persistent_lock); 1131 rsv->next = efi_memreserve_root->next; 1132 efi_memreserve_root->next = __pa(rsv); 1133 spin_unlock(&efi_mem_reserve_persistent_lock); 1134 1135 return efi_mem_reserve_iomem(addr, size); 1136 } 1137 1138 static int __init efi_memreserve_root_init(void) 1139 { 1140 if (efi_memreserve_root) 1141 return 0; 1142 if (efi_memreserve_map_root()) 1143 efi_memreserve_root = (void *)ULONG_MAX; 1144 return 0; 1145 } 1146 early_initcall(efi_memreserve_root_init); 1147 1148 #ifdef CONFIG_KEXEC 1149 static int update_efi_random_seed(struct notifier_block *nb, 1150 unsigned long code, void *unused) 1151 { 1152 struct linux_efi_random_seed *seed; 1153 u32 size = 0; 1154 1155 if (!kexec_in_progress) 1156 return NOTIFY_DONE; 1157 1158 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1159 if (seed != NULL) { 1160 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1161 memunmap(seed); 1162 } else { 1163 pr_err("Could not map UEFI random seed!\n"); 1164 } 1165 if (size > 0) { 1166 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1167 MEMREMAP_WB); 1168 if (seed != NULL) { 1169 seed->size = size; 1170 get_random_bytes(seed->bits, seed->size); 1171 memunmap(seed); 1172 } else { 1173 pr_err("Could not map UEFI random seed!\n"); 1174 } 1175 } 1176 return NOTIFY_DONE; 1177 } 1178 1179 static struct notifier_block efi_random_seed_nb = { 1180 .notifier_call = update_efi_random_seed, 1181 }; 1182 1183 static int __init register_update_efi_random_seed(void) 1184 { 1185 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1186 return 0; 1187 return register_reboot_notifier(&efi_random_seed_nb); 1188 } 1189 late_initcall(register_update_efi_random_seed); 1190 #endif 1191