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 if (!efi.get_next_variable) 207 return false; 208 status = efi.get_next_variable(&name_size, &name, &guid); 209 if (status == EFI_UNSUPPORTED) 210 return false; 211 212 return true; 213 } 214 215 static int generic_ops_register(void) 216 { 217 if (!generic_ops_supported()) 218 return 0; 219 220 generic_ops.get_variable = efi.get_variable; 221 generic_ops.get_next_variable = efi.get_next_variable; 222 generic_ops.query_variable_store = efi_query_variable_store; 223 generic_ops.query_variable_info = efi.query_variable_info; 224 225 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) { 226 generic_ops.set_variable = efi.set_variable; 227 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; 228 } 229 return efivars_register(&generic_efivars, &generic_ops); 230 } 231 232 static void generic_ops_unregister(void) 233 { 234 if (!generic_ops.get_variable) 235 return; 236 237 efivars_unregister(&generic_efivars); 238 } 239 240 void efivars_generic_ops_register(void) 241 { 242 generic_ops_register(); 243 } 244 EXPORT_SYMBOL_GPL(efivars_generic_ops_register); 245 246 void efivars_generic_ops_unregister(void) 247 { 248 generic_ops_unregister(); 249 } 250 EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister); 251 252 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS 253 #define EFIVAR_SSDT_NAME_MAX 16UL 254 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; 255 static int __init efivar_ssdt_setup(char *str) 256 { 257 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); 258 259 if (ret) 260 return ret; 261 262 if (strlen(str) < sizeof(efivar_ssdt)) 263 memcpy(efivar_ssdt, str, strlen(str)); 264 else 265 pr_warn("efivar_ssdt: name too long: %s\n", str); 266 return 1; 267 } 268 __setup("efivar_ssdt=", efivar_ssdt_setup); 269 270 static __init int efivar_ssdt_load(void) 271 { 272 unsigned long name_size = 256; 273 efi_char16_t *name = NULL; 274 efi_status_t status; 275 efi_guid_t guid; 276 int ret = 0; 277 278 if (!efivar_ssdt[0]) 279 return 0; 280 281 name = kzalloc(name_size, GFP_KERNEL); 282 if (!name) 283 return -ENOMEM; 284 285 for (;;) { 286 char utf8_name[EFIVAR_SSDT_NAME_MAX]; 287 unsigned long data_size = 0; 288 void *data; 289 int limit; 290 291 status = efi.get_next_variable(&name_size, name, &guid); 292 if (status == EFI_NOT_FOUND) { 293 break; 294 } else if (status == EFI_BUFFER_TOO_SMALL) { 295 efi_char16_t *name_tmp = 296 krealloc(name, name_size, GFP_KERNEL); 297 if (!name_tmp) { 298 ret = -ENOMEM; 299 goto out; 300 } 301 name = name_tmp; 302 continue; 303 } 304 305 limit = min(EFIVAR_SSDT_NAME_MAX, name_size); 306 ucs2_as_utf8(utf8_name, name, limit - 1); 307 if (strncmp(utf8_name, efivar_ssdt, limit) != 0) 308 continue; 309 310 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid); 311 312 status = efi.get_variable(name, &guid, NULL, &data_size, NULL); 313 if (status != EFI_BUFFER_TOO_SMALL || !data_size) { 314 ret = -EIO; 315 goto out; 316 } 317 318 data = kmalloc(data_size, GFP_KERNEL); 319 if (!data) { 320 ret = -ENOMEM; 321 goto out; 322 } 323 324 status = efi.get_variable(name, &guid, NULL, &data_size, data); 325 if (status == EFI_SUCCESS) { 326 acpi_status acpi_ret = acpi_load_table(data, NULL); 327 if (ACPI_FAILURE(acpi_ret)) { 328 pr_err("efivar_ssdt: failed to load table: %u\n", 329 acpi_ret); 330 } else { 331 /* 332 * The @data will be in use by ACPI engine, 333 * do not free it! 334 */ 335 continue; 336 } 337 } else { 338 pr_err("efivar_ssdt: failed to get var data: 0x%lx\n", status); 339 } 340 kfree(data); 341 } 342 out: 343 kfree(name); 344 return ret; 345 } 346 #else 347 static inline int efivar_ssdt_load(void) { return 0; } 348 #endif 349 350 #ifdef CONFIG_DEBUG_FS 351 352 #define EFI_DEBUGFS_MAX_BLOBS 32 353 354 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; 355 356 static void __init efi_debugfs_init(void) 357 { 358 struct dentry *efi_debugfs; 359 efi_memory_desc_t *md; 360 char name[32]; 361 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; 362 int i = 0; 363 364 efi_debugfs = debugfs_create_dir("efi", NULL); 365 if (IS_ERR(efi_debugfs)) 366 return; 367 368 for_each_efi_memory_desc(md) { 369 switch (md->type) { 370 case EFI_BOOT_SERVICES_CODE: 371 snprintf(name, sizeof(name), "boot_services_code%d", 372 type_count[md->type]++); 373 break; 374 case EFI_BOOT_SERVICES_DATA: 375 snprintf(name, sizeof(name), "boot_services_data%d", 376 type_count[md->type]++); 377 break; 378 default: 379 continue; 380 } 381 382 if (i >= EFI_DEBUGFS_MAX_BLOBS) { 383 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n", 384 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); 385 break; 386 } 387 388 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; 389 debugfs_blob[i].data = memremap(md->phys_addr, 390 debugfs_blob[i].size, 391 MEMREMAP_WB); 392 if (!debugfs_blob[i].data) 393 continue; 394 395 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); 396 i++; 397 } 398 } 399 #else 400 static inline void efi_debugfs_init(void) {} 401 #endif 402 403 /* 404 * We register the efi subsystem with the firmware subsystem and the 405 * efivars subsystem with the efi subsystem, if the system was booted with 406 * EFI. 407 */ 408 static int __init efisubsys_init(void) 409 { 410 int error; 411 412 if (!efi_enabled(EFI_RUNTIME_SERVICES)) 413 efi.runtime_supported_mask = 0; 414 415 if (!efi_enabled(EFI_BOOT)) 416 return 0; 417 418 if (efi.runtime_supported_mask) { 419 /* 420 * Since we process only one efi_runtime_service() at a time, an 421 * ordered workqueue (which creates only one execution context) 422 * should suffice for all our needs. 423 */ 424 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); 425 if (!efi_rts_wq) { 426 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); 427 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); 428 efi.runtime_supported_mask = 0; 429 return 0; 430 } 431 } 432 433 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES)) 434 platform_device_register_simple("rtc-efi", 0, NULL, 0); 435 436 /* We register the efi directory at /sys/firmware/efi */ 437 efi_kobj = kobject_create_and_add("efi", firmware_kobj); 438 if (!efi_kobj) { 439 pr_err("efi: Firmware registration failed.\n"); 440 error = -ENOMEM; 441 goto err_destroy_wq; 442 } 443 444 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 445 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) { 446 error = generic_ops_register(); 447 if (error) 448 goto err_put; 449 error = efivar_ssdt_load(); 450 if (error) 451 pr_err("efi: failed to load SSDT, error %d.\n", error); 452 platform_device_register_simple("efivars", 0, NULL, 0); 453 } 454 455 BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh); 456 457 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); 458 if (error) { 459 pr_err("efi: Sysfs attribute export failed with error %d.\n", 460 error); 461 goto err_unregister; 462 } 463 464 /* and the standard mountpoint for efivarfs */ 465 error = sysfs_create_mount_point(efi_kobj, "efivars"); 466 if (error) { 467 pr_err("efivars: Subsystem registration failed.\n"); 468 goto err_remove_group; 469 } 470 471 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) 472 efi_debugfs_init(); 473 474 #ifdef CONFIG_EFI_COCO_SECRET 475 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR) 476 platform_device_register_simple("efi_secret", 0, NULL, 0); 477 #endif 478 479 return 0; 480 481 err_remove_group: 482 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); 483 err_unregister: 484 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | 485 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) 486 generic_ops_unregister(); 487 err_put: 488 kobject_put(efi_kobj); 489 efi_kobj = NULL; 490 err_destroy_wq: 491 if (efi_rts_wq) 492 destroy_workqueue(efi_rts_wq); 493 494 return error; 495 } 496 497 subsys_initcall(efisubsys_init); 498 499 void __init efi_find_mirror(void) 500 { 501 efi_memory_desc_t *md; 502 u64 mirror_size = 0, total_size = 0; 503 504 if (!efi_enabled(EFI_MEMMAP)) 505 return; 506 507 for_each_efi_memory_desc(md) { 508 unsigned long long start = md->phys_addr; 509 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT; 510 511 total_size += size; 512 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) { 513 memblock_mark_mirror(start, size); 514 mirror_size += size; 515 } 516 } 517 if (mirror_size) 518 pr_info("Memory: %lldM/%lldM mirrored memory\n", 519 mirror_size>>20, total_size>>20); 520 } 521 522 /* 523 * Find the efi memory descriptor for a given physical address. Given a 524 * physical address, determine if it exists within an EFI Memory Map entry, 525 * and if so, populate the supplied memory descriptor with the appropriate 526 * data. 527 */ 528 int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 529 { 530 efi_memory_desc_t *md; 531 532 if (!efi_enabled(EFI_MEMMAP)) { 533 pr_err_once("EFI_MEMMAP is not enabled.\n"); 534 return -EINVAL; 535 } 536 537 if (!out_md) { 538 pr_err_once("out_md is null.\n"); 539 return -EINVAL; 540 } 541 542 for_each_efi_memory_desc(md) { 543 u64 size; 544 u64 end; 545 546 /* skip bogus entries (including empty ones) */ 547 if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) || 548 (md->num_pages <= 0) || 549 (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT)) 550 continue; 551 552 size = md->num_pages << EFI_PAGE_SHIFT; 553 end = md->phys_addr + size; 554 if (phys_addr >= md->phys_addr && phys_addr < end) { 555 memcpy(out_md, md, sizeof(*out_md)); 556 return 0; 557 } 558 } 559 return -ENOENT; 560 } 561 562 extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) 563 __weak __alias(__efi_mem_desc_lookup); 564 565 /* 566 * Calculate the highest address of an efi memory descriptor. 567 */ 568 u64 __init efi_mem_desc_end(efi_memory_desc_t *md) 569 { 570 u64 size = md->num_pages << EFI_PAGE_SHIFT; 571 u64 end = md->phys_addr + size; 572 return end; 573 } 574 575 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} 576 577 /** 578 * efi_mem_reserve - Reserve an EFI memory region 579 * @addr: Physical address to reserve 580 * @size: Size of reservation 581 * 582 * Mark a region as reserved from general kernel allocation and 583 * prevent it being released by efi_free_boot_services(). 584 * 585 * This function should be called drivers once they've parsed EFI 586 * configuration tables to figure out where their data lives, e.g. 587 * efi_esrt_init(). 588 */ 589 void __init efi_mem_reserve(phys_addr_t addr, u64 size) 590 { 591 /* efi_mem_reserve() does not work under Xen */ 592 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT))) 593 return; 594 595 if (!memblock_is_region_reserved(addr, size)) 596 memblock_reserve(addr, size); 597 598 /* 599 * Some architectures (x86) reserve all boot services ranges 600 * until efi_free_boot_services() because of buggy firmware 601 * implementations. This means the above memblock_reserve() is 602 * superfluous on x86 and instead what it needs to do is 603 * ensure the @start, @size is not freed. 604 */ 605 efi_arch_mem_reserve(addr, size); 606 } 607 608 static const efi_config_table_type_t common_tables[] __initconst = { 609 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" }, 610 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" }, 611 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" }, 612 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" }, 613 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" }, 614 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" }, 615 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" }, 616 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" }, 617 {EFI_TCG2_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "TPMFinalLog" }, 618 {EFI_CC_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "CCFinalLog" }, 619 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" }, 620 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" }, 621 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" }, 622 #ifdef CONFIG_EFI_RCI2_TABLE 623 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys }, 624 #endif 625 #ifdef CONFIG_LOAD_UEFI_KEYS 626 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" }, 627 #endif 628 #ifdef CONFIG_EFI_COCO_SECRET 629 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, 630 #endif 631 #ifdef CONFIG_UNACCEPTED_MEMORY 632 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" }, 633 #endif 634 #ifdef CONFIG_EFI_GENERIC_STUB 635 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table }, 636 #endif 637 {}, 638 }; 639 640 static __init int match_config_table(const efi_guid_t *guid, 641 unsigned long table, 642 const efi_config_table_type_t *table_types) 643 { 644 int i; 645 646 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { 647 if (efi_guidcmp(*guid, table_types[i].guid)) 648 continue; 649 650 if (!efi_config_table_is_usable(guid, table)) { 651 if (table_types[i].name[0]) 652 pr_cont("(%s=0x%lx unusable) ", 653 table_types[i].name, table); 654 return 1; 655 } 656 657 *(table_types[i].ptr) = table; 658 if (table_types[i].name[0]) 659 pr_cont("%s=0x%lx ", table_types[i].name, table); 660 return 1; 661 } 662 663 return 0; 664 } 665 666 /** 667 * reserve_unaccepted - Map and reserve unaccepted configuration table 668 * @unaccepted: Pointer to unaccepted memory table 669 * 670 * memblock_add() makes sure that the table is mapped in direct mapping. During 671 * normal boot it happens automatically because the table is allocated from 672 * usable memory. But during crashkernel boot only memory specifically reserved 673 * for crash scenario is mapped. memblock_add() forces the table to be mapped 674 * in crashkernel case. 675 * 676 * Align the range to the nearest page borders. Ranges smaller than page size 677 * are not going to be mapped. 678 * 679 * memblock_reserve() makes sure that future allocations will not touch the 680 * table. 681 */ 682 683 static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted) 684 { 685 phys_addr_t start, size; 686 687 start = PAGE_ALIGN_DOWN(efi.unaccepted); 688 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size); 689 690 memblock_add(start, size); 691 memblock_reserve(start, size); 692 } 693 694 int __init efi_config_parse_tables(const efi_config_table_t *config_tables, 695 int count, 696 const efi_config_table_type_t *arch_tables) 697 { 698 const efi_config_table_64_t *tbl64 = (void *)config_tables; 699 const efi_config_table_32_t *tbl32 = (void *)config_tables; 700 const efi_guid_t *guid; 701 unsigned long table; 702 int i; 703 704 pr_info(""); 705 for (i = 0; i < count; i++) { 706 if (!IS_ENABLED(CONFIG_X86)) { 707 guid = &config_tables[i].guid; 708 table = (unsigned long)config_tables[i].table; 709 } else if (efi_enabled(EFI_64BIT)) { 710 guid = &tbl64[i].guid; 711 table = tbl64[i].table; 712 713 if (IS_ENABLED(CONFIG_X86_32) && 714 tbl64[i].table > U32_MAX) { 715 pr_cont("\n"); 716 pr_err("Table located above 4GB, disabling EFI.\n"); 717 return -EINVAL; 718 } 719 } else { 720 guid = &tbl32[i].guid; 721 table = tbl32[i].table; 722 } 723 724 if (!match_config_table(guid, table, common_tables) && arch_tables) 725 match_config_table(guid, table, arch_tables); 726 } 727 pr_cont("\n"); 728 set_bit(EFI_CONFIG_TABLES, &efi.flags); 729 730 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) { 731 struct linux_efi_random_seed *seed; 732 u32 size = 0; 733 734 seed = early_memremap(efi_rng_seed, sizeof(*seed)); 735 if (seed != NULL) { 736 size = min_t(u32, seed->size, SZ_1K); // sanity check 737 early_memunmap(seed, sizeof(*seed)); 738 } else { 739 pr_err("Could not map UEFI random seed!\n"); 740 } 741 if (size > 0) { 742 seed = early_memremap(efi_rng_seed, 743 sizeof(*seed) + size); 744 if (seed != NULL) { 745 add_bootloader_randomness(seed->bits, size); 746 memzero_explicit(seed->bits, size); 747 early_memunmap(seed, sizeof(*seed) + size); 748 } else { 749 pr_err("Could not map UEFI random seed!\n"); 750 } 751 } 752 } 753 754 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP)) 755 efi_memattr_init(); 756 757 efi_tpm_eventlog_init(); 758 759 if (mem_reserve != EFI_INVALID_TABLE_ADDR) { 760 unsigned long prsv = mem_reserve; 761 762 while (prsv) { 763 struct linux_efi_memreserve *rsv; 764 u8 *p; 765 766 /* 767 * Just map a full page: that is what we will get 768 * anyway, and it permits us to map the entire entry 769 * before knowing its size. 770 */ 771 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), 772 PAGE_SIZE); 773 if (p == NULL) { 774 pr_err("Could not map UEFI memreserve entry!\n"); 775 return -ENOMEM; 776 } 777 778 rsv = (void *)(p + prsv % PAGE_SIZE); 779 780 /* reserve the entry itself */ 781 memblock_reserve(prsv, 782 struct_size(rsv, entry, rsv->size)); 783 784 for (i = 0; i < atomic_read(&rsv->count); i++) { 785 memblock_reserve(rsv->entry[i].base, 786 rsv->entry[i].size); 787 } 788 789 prsv = rsv->next; 790 early_memunmap(p, PAGE_SIZE); 791 } 792 } 793 794 if (rt_prop != EFI_INVALID_TABLE_ADDR) { 795 efi_rt_properties_table_t *tbl; 796 797 tbl = early_memremap(rt_prop, sizeof(*tbl)); 798 if (tbl) { 799 efi.runtime_supported_mask &= tbl->runtime_services_supported; 800 early_memunmap(tbl, sizeof(*tbl)); 801 } 802 } 803 804 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && 805 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) { 806 struct linux_efi_initrd *tbl; 807 808 tbl = early_memremap(initrd, sizeof(*tbl)); 809 if (tbl) { 810 phys_initrd_start = tbl->base; 811 phys_initrd_size = tbl->size; 812 early_memunmap(tbl, sizeof(*tbl)); 813 } 814 } 815 816 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && 817 efi.unaccepted != EFI_INVALID_TABLE_ADDR) { 818 struct efi_unaccepted_memory *unaccepted; 819 820 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted)); 821 if (unaccepted) { 822 823 if (unaccepted->version == 1) { 824 reserve_unaccepted(unaccepted); 825 } else { 826 efi.unaccepted = EFI_INVALID_TABLE_ADDR; 827 } 828 829 early_memunmap(unaccepted, sizeof(*unaccepted)); 830 } 831 } 832 833 return 0; 834 } 835 836 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr) 837 { 838 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) { 839 pr_err("System table signature incorrect!\n"); 840 return -EINVAL; 841 } 842 843 return 0; 844 } 845 846 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor, 847 size_t size) 848 { 849 const efi_char16_t *ret; 850 851 ret = early_memremap_ro(fw_vendor, size); 852 if (!ret) 853 pr_err("Could not map the firmware vendor!\n"); 854 return ret; 855 } 856 857 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size) 858 { 859 early_memunmap((void *)fw_vendor, size); 860 } 861 862 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr, 863 unsigned long fw_vendor) 864 { 865 char vendor[100] = "unknown"; 866 const efi_char16_t *c16; 867 size_t i; 868 u16 rev; 869 870 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t)); 871 if (c16) { 872 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i) 873 vendor[i] = c16[i]; 874 vendor[i] = '\0'; 875 876 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t)); 877 } 878 879 rev = (u16)systab_hdr->revision; 880 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10); 881 882 rev %= 10; 883 if (rev) 884 pr_cont(".%u", rev); 885 886 pr_cont(" by %s\n", vendor); 887 888 if (IS_ENABLED(CONFIG_X86_64) && 889 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION && 890 !strcmp(vendor, "Apple")) { 891 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n"); 892 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION; 893 } 894 } 895 896 static __initdata char memory_type_name[][13] = { 897 "Reserved", 898 "Loader Code", 899 "Loader Data", 900 "Boot Code", 901 "Boot Data", 902 "Runtime Code", 903 "Runtime Data", 904 "Conventional", 905 "Unusable", 906 "ACPI Reclaim", 907 "ACPI Mem NVS", 908 "MMIO", 909 "MMIO Port", 910 "PAL Code", 911 "Persistent", 912 "Unaccepted", 913 }; 914 915 char * __init efi_md_typeattr_format(char *buf, size_t size, 916 const efi_memory_desc_t *md) 917 { 918 char *pos; 919 int type_len; 920 u64 attr; 921 922 pos = buf; 923 if (md->type >= ARRAY_SIZE(memory_type_name)) 924 type_len = snprintf(pos, size, "[type=%u", md->type); 925 else 926 type_len = snprintf(pos, size, "[%-*s", 927 (int)(sizeof(memory_type_name[0]) - 1), 928 memory_type_name[md->type]); 929 if (type_len >= size) 930 return buf; 931 932 pos += type_len; 933 size -= type_len; 934 935 attr = md->attribute; 936 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | 937 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | 938 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | 939 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO | 940 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) 941 snprintf(pos, size, "|attr=0x%016llx]", 942 (unsigned long long)attr); 943 else 944 snprintf(pos, size, 945 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", 946 attr & EFI_MEMORY_RUNTIME ? "RUN" : "", 947 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", 948 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "", 949 attr & EFI_MEMORY_SP ? "SP" : "", 950 attr & EFI_MEMORY_NV ? "NV" : "", 951 attr & EFI_MEMORY_XP ? "XP" : "", 952 attr & EFI_MEMORY_RP ? "RP" : "", 953 attr & EFI_MEMORY_WP ? "WP" : "", 954 attr & EFI_MEMORY_RO ? "RO" : "", 955 attr & EFI_MEMORY_UCE ? "UCE" : "", 956 attr & EFI_MEMORY_WB ? "WB" : "", 957 attr & EFI_MEMORY_WT ? "WT" : "", 958 attr & EFI_MEMORY_WC ? "WC" : "", 959 attr & EFI_MEMORY_UC ? "UC" : ""); 960 return buf; 961 } 962 963 /* 964 * efi_mem_attributes - lookup memmap attributes for physical address 965 * @phys_addr: the physical address to lookup 966 * 967 * Search in the EFI memory map for the region covering 968 * @phys_addr. Returns the EFI memory attributes if the region 969 * was found in the memory map, 0 otherwise. 970 */ 971 u64 efi_mem_attributes(unsigned long phys_addr) 972 { 973 efi_memory_desc_t *md; 974 975 if (!efi_enabled(EFI_MEMMAP)) 976 return 0; 977 978 for_each_efi_memory_desc(md) { 979 if ((md->phys_addr <= phys_addr) && 980 (phys_addr < (md->phys_addr + 981 (md->num_pages << EFI_PAGE_SHIFT)))) 982 return md->attribute; 983 } 984 return 0; 985 } 986 987 /* 988 * efi_mem_type - lookup memmap type for physical address 989 * @phys_addr: the physical address to lookup 990 * 991 * Search in the EFI memory map for the region covering @phys_addr. 992 * Returns the EFI memory type if the region was found in the memory 993 * map, -EINVAL otherwise. 994 */ 995 int efi_mem_type(unsigned long phys_addr) 996 { 997 const efi_memory_desc_t *md; 998 999 if (!efi_enabled(EFI_MEMMAP)) 1000 return -ENOTSUPP; 1001 1002 for_each_efi_memory_desc(md) { 1003 if ((md->phys_addr <= phys_addr) && 1004 (phys_addr < (md->phys_addr + 1005 (md->num_pages << EFI_PAGE_SHIFT)))) 1006 return md->type; 1007 } 1008 return -EINVAL; 1009 } 1010 1011 int efi_status_to_err(efi_status_t status) 1012 { 1013 int err; 1014 1015 switch (status) { 1016 case EFI_SUCCESS: 1017 err = 0; 1018 break; 1019 case EFI_INVALID_PARAMETER: 1020 err = -EINVAL; 1021 break; 1022 case EFI_OUT_OF_RESOURCES: 1023 err = -ENOSPC; 1024 break; 1025 case EFI_DEVICE_ERROR: 1026 err = -EIO; 1027 break; 1028 case EFI_WRITE_PROTECTED: 1029 err = -EROFS; 1030 break; 1031 case EFI_SECURITY_VIOLATION: 1032 err = -EACCES; 1033 break; 1034 case EFI_NOT_FOUND: 1035 err = -ENOENT; 1036 break; 1037 case EFI_ABORTED: 1038 err = -EINTR; 1039 break; 1040 default: 1041 err = -EINVAL; 1042 } 1043 1044 return err; 1045 } 1046 EXPORT_SYMBOL_GPL(efi_status_to_err); 1047 1048 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); 1049 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 1050 1051 static int __init efi_memreserve_map_root(void) 1052 { 1053 if (mem_reserve == EFI_INVALID_TABLE_ADDR) 1054 return -ENODEV; 1055 1056 efi_memreserve_root = memremap(mem_reserve, 1057 sizeof(*efi_memreserve_root), 1058 MEMREMAP_WB); 1059 if (WARN_ON_ONCE(!efi_memreserve_root)) 1060 return -ENOMEM; 1061 return 0; 1062 } 1063 1064 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) 1065 { 1066 struct resource *res, *parent; 1067 int ret; 1068 1069 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 1070 if (!res) 1071 return -ENOMEM; 1072 1073 res->name = "reserved"; 1074 res->flags = IORESOURCE_MEM; 1075 res->start = addr; 1076 res->end = addr + size - 1; 1077 1078 /* we expect a conflict with a 'System RAM' region */ 1079 parent = request_resource_conflict(&iomem_resource, res); 1080 ret = parent ? request_resource(parent, res) : 0; 1081 1082 /* 1083 * Given that efi_mem_reserve_iomem() can be called at any 1084 * time, only call memblock_reserve() if the architecture 1085 * keeps the infrastructure around. 1086 */ 1087 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret) 1088 memblock_reserve(addr, size); 1089 1090 return ret; 1091 } 1092 1093 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) 1094 { 1095 struct linux_efi_memreserve *rsv; 1096 unsigned long prsv; 1097 int rc, index; 1098 1099 if (efi_memreserve_root == (void *)ULONG_MAX) 1100 return -ENODEV; 1101 1102 if (!efi_memreserve_root) { 1103 rc = efi_memreserve_map_root(); 1104 if (rc) 1105 return rc; 1106 } 1107 1108 /* first try to find a slot in an existing linked list entry */ 1109 for (prsv = efi_memreserve_root->next; prsv; ) { 1110 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); 1111 if (!rsv) 1112 return -ENOMEM; 1113 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); 1114 if (index < rsv->size) { 1115 rsv->entry[index].base = addr; 1116 rsv->entry[index].size = size; 1117 1118 memunmap(rsv); 1119 return efi_mem_reserve_iomem(addr, size); 1120 } 1121 prsv = rsv->next; 1122 memunmap(rsv); 1123 } 1124 1125 /* no slot found - allocate a new linked list entry */ 1126 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); 1127 if (!rsv) 1128 return -ENOMEM; 1129 1130 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); 1131 if (rc) { 1132 free_page((unsigned long)rsv); 1133 return rc; 1134 } 1135 1136 /* 1137 * The memremap() call above assumes that a linux_efi_memreserve entry 1138 * never crosses a page boundary, so let's ensure that this remains true 1139 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by 1140 * using SZ_4K explicitly in the size calculation below. 1141 */ 1142 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); 1143 atomic_set(&rsv->count, 1); 1144 rsv->entry[0].base = addr; 1145 rsv->entry[0].size = size; 1146 1147 spin_lock(&efi_mem_reserve_persistent_lock); 1148 rsv->next = efi_memreserve_root->next; 1149 efi_memreserve_root->next = __pa(rsv); 1150 spin_unlock(&efi_mem_reserve_persistent_lock); 1151 1152 return efi_mem_reserve_iomem(addr, size); 1153 } 1154 1155 static int __init efi_memreserve_root_init(void) 1156 { 1157 if (efi_memreserve_root) 1158 return 0; 1159 if (efi_memreserve_map_root()) 1160 efi_memreserve_root = (void *)ULONG_MAX; 1161 return 0; 1162 } 1163 early_initcall(efi_memreserve_root_init); 1164 1165 #ifdef CONFIG_KEXEC 1166 static int update_efi_random_seed(struct notifier_block *nb, 1167 unsigned long code, void *unused) 1168 { 1169 struct linux_efi_random_seed *seed; 1170 u32 size = 0; 1171 1172 if (!kexec_in_progress) 1173 return NOTIFY_DONE; 1174 1175 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB); 1176 if (seed != NULL) { 1177 size = min(seed->size, EFI_RANDOM_SEED_SIZE); 1178 memunmap(seed); 1179 } else { 1180 pr_err("Could not map UEFI random seed!\n"); 1181 } 1182 if (size > 0) { 1183 seed = memremap(efi_rng_seed, sizeof(*seed) + size, 1184 MEMREMAP_WB); 1185 if (seed != NULL) { 1186 seed->size = size; 1187 get_random_bytes(seed->bits, seed->size); 1188 memunmap(seed); 1189 } else { 1190 pr_err("Could not map UEFI random seed!\n"); 1191 } 1192 } 1193 return NOTIFY_DONE; 1194 } 1195 1196 static struct notifier_block efi_random_seed_nb = { 1197 .notifier_call = update_efi_random_seed, 1198 }; 1199 1200 static int __init register_update_efi_random_seed(void) 1201 { 1202 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR) 1203 return 0; 1204 return register_reboot_notifier(&efi_random_seed_nb); 1205 } 1206 late_initcall(register_update_efi_random_seed); 1207 #endif 1208