1 // SPDX-License-Identifier: GPL-2.0-only
3 * efi.c - EFI subsystem
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>
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.
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
24 #include <linux/initrd.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>
36 #include <asm/early_ioremap.h>
38 struct efi __read_mostly efi = {
39 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
40 .acpi = EFI_INVALID_TABLE_ADDR,
41 .acpi20 = EFI_INVALID_TABLE_ADDR,
42 .smbios = EFI_INVALID_TABLE_ADDR,
43 .smbios3 = EFI_INVALID_TABLE_ADDR,
44 .esrt = EFI_INVALID_TABLE_ADDR,
45 .tpm_log = EFI_INVALID_TABLE_ADDR,
46 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
47 #ifdef CONFIG_LOAD_UEFI_KEYS
48 .mokvar_table = EFI_INVALID_TABLE_ADDR,
50 #ifdef CONFIG_EFI_COCO_SECRET
51 .coco_secret = EFI_INVALID_TABLE_ADDR,
53 #ifdef CONFIG_UNACCEPTED_MEMORY
54 .unaccepted = EFI_INVALID_TABLE_ADDR,
59 unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
60 static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
61 static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
62 static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
64 extern unsigned long screen_info_table;
66 struct mm_struct efi_mm = {
67 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
68 .mm_users = ATOMIC_INIT(2),
69 .mm_count = ATOMIC_INIT(1),
70 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
71 MMAP_LOCK_INITIALIZER(efi_mm)
72 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
73 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
74 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
77 struct workqueue_struct *efi_rts_wq;
79 static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
80 static int __init setup_noefi(char *arg)
82 disable_runtime = true;
85 early_param("noefi", setup_noefi);
87 bool efi_runtime_disabled(void)
89 return disable_runtime;
92 bool __pure __efi_soft_reserve_enabled(void)
94 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
97 static int __init parse_efi_cmdline(char *str)
100 pr_warn("need at least one option\n");
104 if (parse_option_str(str, "debug"))
105 set_bit(EFI_DBG, &efi.flags);
107 if (parse_option_str(str, "noruntime"))
108 disable_runtime = true;
110 if (parse_option_str(str, "runtime"))
111 disable_runtime = false;
113 if (parse_option_str(str, "nosoftreserve"))
114 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
118 early_param("efi", parse_efi_cmdline);
120 struct kobject *efi_kobj;
123 * Let's not leave out systab information that snuck into
125 * Note, do not add more fields in systab sysfs file as it breaks sysfs
126 * one value per file rule!
128 static ssize_t systab_show(struct kobject *kobj,
129 struct kobj_attribute *attr, char *buf)
136 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
137 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
138 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
139 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
141 * If both SMBIOS and SMBIOS3 entry points are implemented, the
142 * SMBIOS3 entry point shall be preferred, so we list it first to
143 * let applications stop parsing after the first match.
145 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
146 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
147 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
148 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
150 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
151 str = efi_systab_show_arch(str);
156 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
158 static ssize_t fw_platform_size_show(struct kobject *kobj,
159 struct kobj_attribute *attr, char *buf)
161 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
164 extern __weak struct kobj_attribute efi_attr_fw_vendor;
165 extern __weak struct kobj_attribute efi_attr_runtime;
166 extern __weak struct kobj_attribute efi_attr_config_table;
167 static struct kobj_attribute efi_attr_fw_platform_size =
168 __ATTR_RO(fw_platform_size);
170 static struct attribute *efi_subsys_attrs[] = {
171 &efi_attr_systab.attr,
172 &efi_attr_fw_platform_size.attr,
173 &efi_attr_fw_vendor.attr,
174 &efi_attr_runtime.attr,
175 &efi_attr_config_table.attr,
179 umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
185 static const struct attribute_group efi_subsys_attr_group = {
186 .attrs = efi_subsys_attrs,
187 .is_visible = efi_attr_is_visible,
190 static struct efivars generic_efivars;
191 static struct efivar_operations generic_ops;
193 static bool generic_ops_supported(void)
195 unsigned long name_size;
200 name_size = sizeof(name);
202 status = efi.get_next_variable(&name_size, &name, &guid);
203 if (status == EFI_UNSUPPORTED)
209 static int generic_ops_register(void)
211 if (!generic_ops_supported())
214 generic_ops.get_variable = efi.get_variable;
215 generic_ops.get_next_variable = efi.get_next_variable;
216 generic_ops.query_variable_store = efi_query_variable_store;
217 generic_ops.query_variable_info = efi.query_variable_info;
219 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
220 generic_ops.set_variable = efi.set_variable;
221 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
223 return efivars_register(&generic_efivars, &generic_ops);
226 static void generic_ops_unregister(void)
228 if (!generic_ops.get_variable)
231 efivars_unregister(&generic_efivars);
234 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
235 #define EFIVAR_SSDT_NAME_MAX 16UL
236 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
237 static int __init efivar_ssdt_setup(char *str)
239 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
244 if (strlen(str) < sizeof(efivar_ssdt))
245 memcpy(efivar_ssdt, str, strlen(str));
247 pr_warn("efivar_ssdt: name too long: %s\n", str);
250 __setup("efivar_ssdt=", efivar_ssdt_setup);
252 static __init int efivar_ssdt_load(void)
254 unsigned long name_size = 256;
255 efi_char16_t *name = NULL;
262 name = kzalloc(name_size, GFP_KERNEL);
267 char utf8_name[EFIVAR_SSDT_NAME_MAX];
268 unsigned long data_size = 0;
272 status = efi.get_next_variable(&name_size, name, &guid);
273 if (status == EFI_NOT_FOUND) {
275 } else if (status == EFI_BUFFER_TOO_SMALL) {
276 efi_char16_t *name_tmp =
277 krealloc(name, name_size, GFP_KERNEL);
286 limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
287 ucs2_as_utf8(utf8_name, name, limit - 1);
288 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
291 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
293 status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
294 if (status != EFI_BUFFER_TOO_SMALL || !data_size)
297 data = kmalloc(data_size, GFP_KERNEL);
301 status = efi.get_variable(name, &guid, NULL, &data_size, data);
302 if (status == EFI_SUCCESS) {
303 acpi_status ret = acpi_load_table(data, NULL);
305 pr_err("failed to load table: %u\n", ret);
309 pr_err("failed to get var data: 0x%lx\n", status);
316 static inline int efivar_ssdt_load(void) { return 0; }
319 #ifdef CONFIG_DEBUG_FS
321 #define EFI_DEBUGFS_MAX_BLOBS 32
323 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
325 static void __init efi_debugfs_init(void)
327 struct dentry *efi_debugfs;
328 efi_memory_desc_t *md;
330 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
333 efi_debugfs = debugfs_create_dir("efi", NULL);
334 if (IS_ERR_OR_NULL(efi_debugfs))
337 for_each_efi_memory_desc(md) {
339 case EFI_BOOT_SERVICES_CODE:
340 snprintf(name, sizeof(name), "boot_services_code%d",
341 type_count[md->type]++);
343 case EFI_BOOT_SERVICES_DATA:
344 snprintf(name, sizeof(name), "boot_services_data%d",
345 type_count[md->type]++);
351 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
352 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
353 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
357 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
358 debugfs_blob[i].data = memremap(md->phys_addr,
359 debugfs_blob[i].size,
361 if (!debugfs_blob[i].data)
364 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
369 static inline void efi_debugfs_init(void) {}
373 * We register the efi subsystem with the firmware subsystem and the
374 * efivars subsystem with the efi subsystem, if the system was booted with
377 static int __init efisubsys_init(void)
381 if (!efi_enabled(EFI_RUNTIME_SERVICES))
382 efi.runtime_supported_mask = 0;
384 if (!efi_enabled(EFI_BOOT))
387 if (efi.runtime_supported_mask) {
389 * Since we process only one efi_runtime_service() at a time, an
390 * ordered workqueue (which creates only one execution context)
391 * should suffice for all our needs.
393 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
395 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
396 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
397 efi.runtime_supported_mask = 0;
402 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
403 platform_device_register_simple("rtc-efi", 0, NULL, 0);
405 /* We register the efi directory at /sys/firmware/efi */
406 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
408 pr_err("efi: Firmware registration failed.\n");
413 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
414 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
415 error = generic_ops_register();
419 platform_device_register_simple("efivars", 0, NULL, 0);
422 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
424 pr_err("efi: Sysfs attribute export failed with error %d.\n",
429 /* and the standard mountpoint for efivarfs */
430 error = sysfs_create_mount_point(efi_kobj, "efivars");
432 pr_err("efivars: Subsystem registration failed.\n");
433 goto err_remove_group;
436 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
439 #ifdef CONFIG_EFI_COCO_SECRET
440 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
441 platform_device_register_simple("efi_secret", 0, NULL, 0);
447 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
449 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
450 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
451 generic_ops_unregister();
453 kobject_put(efi_kobj);
457 destroy_workqueue(efi_rts_wq);
462 subsys_initcall(efisubsys_init);
464 void __init efi_find_mirror(void)
466 efi_memory_desc_t *md;
467 u64 mirror_size = 0, total_size = 0;
469 if (!efi_enabled(EFI_MEMMAP))
472 for_each_efi_memory_desc(md) {
473 unsigned long long start = md->phys_addr;
474 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
477 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
478 memblock_mark_mirror(start, size);
483 pr_info("Memory: %lldM/%lldM mirrored memory\n",
484 mirror_size>>20, total_size>>20);
488 * Find the efi memory descriptor for a given physical address. Given a
489 * physical address, determine if it exists within an EFI Memory Map entry,
490 * and if so, populate the supplied memory descriptor with the appropriate
493 int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
495 efi_memory_desc_t *md;
497 if (!efi_enabled(EFI_MEMMAP)) {
498 pr_err_once("EFI_MEMMAP is not enabled.\n");
503 pr_err_once("out_md is null.\n");
507 for_each_efi_memory_desc(md) {
511 /* skip bogus entries (including empty ones) */
512 if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
513 (md->num_pages <= 0) ||
514 (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
517 size = md->num_pages << EFI_PAGE_SHIFT;
518 end = md->phys_addr + size;
519 if (phys_addr >= md->phys_addr && phys_addr < end) {
520 memcpy(out_md, md, sizeof(*out_md));
527 extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
528 __weak __alias(__efi_mem_desc_lookup);
531 * Calculate the highest address of an efi memory descriptor.
533 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
535 u64 size = md->num_pages << EFI_PAGE_SHIFT;
536 u64 end = md->phys_addr + size;
540 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
543 * efi_mem_reserve - Reserve an EFI memory region
544 * @addr: Physical address to reserve
545 * @size: Size of reservation
547 * Mark a region as reserved from general kernel allocation and
548 * prevent it being released by efi_free_boot_services().
550 * This function should be called drivers once they've parsed EFI
551 * configuration tables to figure out where their data lives, e.g.
554 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
556 /* efi_mem_reserve() does not work under Xen */
557 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
560 if (!memblock_is_region_reserved(addr, size))
561 memblock_reserve(addr, size);
564 * Some architectures (x86) reserve all boot services ranges
565 * until efi_free_boot_services() because of buggy firmware
566 * implementations. This means the above memblock_reserve() is
567 * superfluous on x86 and instead what it needs to do is
568 * ensure the @start, @size is not freed.
570 efi_arch_mem_reserve(addr, size);
573 static const efi_config_table_type_t common_tables[] __initconst = {
574 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
575 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
576 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
577 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
578 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
579 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
580 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
581 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
582 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" },
583 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
584 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
585 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
586 #ifdef CONFIG_EFI_RCI2_TABLE
587 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
589 #ifdef CONFIG_LOAD_UEFI_KEYS
590 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
592 #ifdef CONFIG_EFI_COCO_SECRET
593 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" },
595 #ifdef CONFIG_UNACCEPTED_MEMORY
596 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" },
598 #ifdef CONFIG_EFI_GENERIC_STUB
599 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table },
604 static __init int match_config_table(const efi_guid_t *guid,
606 const efi_config_table_type_t *table_types)
610 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
611 if (efi_guidcmp(*guid, table_types[i].guid))
614 if (!efi_config_table_is_usable(guid, table)) {
615 if (table_types[i].name[0])
616 pr_cont("(%s=0x%lx unusable) ",
617 table_types[i].name, table);
621 *(table_types[i].ptr) = table;
622 if (table_types[i].name[0])
623 pr_cont("%s=0x%lx ", table_types[i].name, table);
631 * reserve_unaccepted - Map and reserve unaccepted configuration table
632 * @unaccepted: Pointer to unaccepted memory table
634 * memblock_add() makes sure that the table is mapped in direct mapping. During
635 * normal boot it happens automatically because the table is allocated from
636 * usable memory. But during crashkernel boot only memory specifically reserved
637 * for crash scenario is mapped. memblock_add() forces the table to be mapped
638 * in crashkernel case.
640 * Align the range to the nearest page borders. Ranges smaller than page size
641 * are not going to be mapped.
643 * memblock_reserve() makes sure that future allocations will not touch the
647 static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
649 phys_addr_t start, size;
651 start = PAGE_ALIGN_DOWN(efi.unaccepted);
652 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size);
654 memblock_add(start, size);
655 memblock_reserve(start, size);
658 int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
660 const efi_config_table_type_t *arch_tables)
662 const efi_config_table_64_t *tbl64 = (void *)config_tables;
663 const efi_config_table_32_t *tbl32 = (void *)config_tables;
664 const efi_guid_t *guid;
669 for (i = 0; i < count; i++) {
670 if (!IS_ENABLED(CONFIG_X86)) {
671 guid = &config_tables[i].guid;
672 table = (unsigned long)config_tables[i].table;
673 } else if (efi_enabled(EFI_64BIT)) {
674 guid = &tbl64[i].guid;
675 table = tbl64[i].table;
677 if (IS_ENABLED(CONFIG_X86_32) &&
678 tbl64[i].table > U32_MAX) {
680 pr_err("Table located above 4GB, disabling EFI.\n");
684 guid = &tbl32[i].guid;
685 table = tbl32[i].table;
688 if (!match_config_table(guid, table, common_tables) && arch_tables)
689 match_config_table(guid, table, arch_tables);
692 set_bit(EFI_CONFIG_TABLES, &efi.flags);
694 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
695 struct linux_efi_random_seed *seed;
698 seed = early_memremap(efi_rng_seed, sizeof(*seed));
700 size = min_t(u32, seed->size, SZ_1K); // sanity check
701 early_memunmap(seed, sizeof(*seed));
703 pr_err("Could not map UEFI random seed!\n");
706 seed = early_memremap(efi_rng_seed,
707 sizeof(*seed) + size);
709 add_bootloader_randomness(seed->bits, size);
710 memzero_explicit(seed->bits, size);
711 early_memunmap(seed, sizeof(*seed) + size);
713 pr_err("Could not map UEFI random seed!\n");
718 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
721 efi_tpm_eventlog_init();
723 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
724 unsigned long prsv = mem_reserve;
727 struct linux_efi_memreserve *rsv;
731 * Just map a full page: that is what we will get
732 * anyway, and it permits us to map the entire entry
733 * before knowing its size.
735 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
738 pr_err("Could not map UEFI memreserve entry!\n");
742 rsv = (void *)(p + prsv % PAGE_SIZE);
744 /* reserve the entry itself */
745 memblock_reserve(prsv,
746 struct_size(rsv, entry, rsv->size));
748 for (i = 0; i < atomic_read(&rsv->count); i++) {
749 memblock_reserve(rsv->entry[i].base,
754 early_memunmap(p, PAGE_SIZE);
758 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
759 efi_rt_properties_table_t *tbl;
761 tbl = early_memremap(rt_prop, sizeof(*tbl));
763 efi.runtime_supported_mask &= tbl->runtime_services_supported;
764 early_memunmap(tbl, sizeof(*tbl));
768 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
769 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
770 struct linux_efi_initrd *tbl;
772 tbl = early_memremap(initrd, sizeof(*tbl));
774 phys_initrd_start = tbl->base;
775 phys_initrd_size = tbl->size;
776 early_memunmap(tbl, sizeof(*tbl));
780 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) &&
781 efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
782 struct efi_unaccepted_memory *unaccepted;
784 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted));
787 if (unaccepted->version == 1) {
788 reserve_unaccepted(unaccepted);
790 efi.unaccepted = EFI_INVALID_TABLE_ADDR;
793 early_memunmap(unaccepted, sizeof(*unaccepted));
800 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
802 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
803 pr_err("System table signature incorrect!\n");
811 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
814 const efi_char16_t *ret;
816 ret = early_memremap_ro(fw_vendor, size);
818 pr_err("Could not map the firmware vendor!\n");
822 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
824 early_memunmap((void *)fw_vendor, size);
827 #define map_fw_vendor(p, s) __va(p)
828 #define unmap_fw_vendor(v, s)
831 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
832 unsigned long fw_vendor)
834 char vendor[100] = "unknown";
835 const efi_char16_t *c16;
839 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
841 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
845 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
848 rev = (u16)systab_hdr->revision;
849 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);
855 pr_cont(" by %s\n", vendor);
857 if (IS_ENABLED(CONFIG_X86_64) &&
858 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
859 !strcmp(vendor, "Apple")) {
860 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
861 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
865 static __initdata char memory_type_name[][13] = {
884 char * __init efi_md_typeattr_format(char *buf, size_t size,
885 const efi_memory_desc_t *md)
892 if (md->type >= ARRAY_SIZE(memory_type_name))
893 type_len = snprintf(pos, size, "[type=%u", md->type);
895 type_len = snprintf(pos, size, "[%-*s",
896 (int)(sizeof(memory_type_name[0]) - 1),
897 memory_type_name[md->type]);
898 if (type_len >= size)
904 attr = md->attribute;
905 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
906 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
907 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
908 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
909 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
910 snprintf(pos, size, "|attr=0x%016llx]",
911 (unsigned long long)attr);
914 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
915 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
916 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
917 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
918 attr & EFI_MEMORY_SP ? "SP" : "",
919 attr & EFI_MEMORY_NV ? "NV" : "",
920 attr & EFI_MEMORY_XP ? "XP" : "",
921 attr & EFI_MEMORY_RP ? "RP" : "",
922 attr & EFI_MEMORY_WP ? "WP" : "",
923 attr & EFI_MEMORY_RO ? "RO" : "",
924 attr & EFI_MEMORY_UCE ? "UCE" : "",
925 attr & EFI_MEMORY_WB ? "WB" : "",
926 attr & EFI_MEMORY_WT ? "WT" : "",
927 attr & EFI_MEMORY_WC ? "WC" : "",
928 attr & EFI_MEMORY_UC ? "UC" : "");
933 * IA64 has a funky EFI memory map that doesn't work the same way as
934 * other architectures.
938 * efi_mem_attributes - lookup memmap attributes for physical address
939 * @phys_addr: the physical address to lookup
941 * Search in the EFI memory map for the region covering
942 * @phys_addr. Returns the EFI memory attributes if the region
943 * was found in the memory map, 0 otherwise.
945 u64 efi_mem_attributes(unsigned long phys_addr)
947 efi_memory_desc_t *md;
949 if (!efi_enabled(EFI_MEMMAP))
952 for_each_efi_memory_desc(md) {
953 if ((md->phys_addr <= phys_addr) &&
954 (phys_addr < (md->phys_addr +
955 (md->num_pages << EFI_PAGE_SHIFT))))
956 return md->attribute;
962 * efi_mem_type - lookup memmap type for physical address
963 * @phys_addr: the physical address to lookup
965 * Search in the EFI memory map for the region covering @phys_addr.
966 * Returns the EFI memory type if the region was found in the memory
967 * map, -EINVAL otherwise.
969 int efi_mem_type(unsigned long phys_addr)
971 const efi_memory_desc_t *md;
973 if (!efi_enabled(EFI_MEMMAP))
976 for_each_efi_memory_desc(md) {
977 if ((md->phys_addr <= phys_addr) &&
978 (phys_addr < (md->phys_addr +
979 (md->num_pages << EFI_PAGE_SHIFT))))
986 int efi_status_to_err(efi_status_t status)
994 case EFI_INVALID_PARAMETER:
997 case EFI_OUT_OF_RESOURCES:
1000 case EFI_DEVICE_ERROR:
1003 case EFI_WRITE_PROTECTED:
1006 case EFI_SECURITY_VIOLATION:
1021 EXPORT_SYMBOL_GPL(efi_status_to_err);
1023 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
1024 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
1026 static int __init efi_memreserve_map_root(void)
1028 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
1031 efi_memreserve_root = memremap(mem_reserve,
1032 sizeof(*efi_memreserve_root),
1034 if (WARN_ON_ONCE(!efi_memreserve_root))
1039 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
1041 struct resource *res, *parent;
1044 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
1048 res->name = "reserved";
1049 res->flags = IORESOURCE_MEM;
1051 res->end = addr + size - 1;
1053 /* we expect a conflict with a 'System RAM' region */
1054 parent = request_resource_conflict(&iomem_resource, res);
1055 ret = parent ? request_resource(parent, res) : 0;
1058 * Given that efi_mem_reserve_iomem() can be called at any
1059 * time, only call memblock_reserve() if the architecture
1060 * keeps the infrastructure around.
1062 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
1063 memblock_reserve(addr, size);
1068 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
1070 struct linux_efi_memreserve *rsv;
1074 if (efi_memreserve_root == (void *)ULONG_MAX)
1077 if (!efi_memreserve_root) {
1078 rc = efi_memreserve_map_root();
1083 /* first try to find a slot in an existing linked list entry */
1084 for (prsv = efi_memreserve_root->next; prsv; ) {
1085 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1088 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1089 if (index < rsv->size) {
1090 rsv->entry[index].base = addr;
1091 rsv->entry[index].size = size;
1094 return efi_mem_reserve_iomem(addr, size);
1100 /* no slot found - allocate a new linked list entry */
1101 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1105 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1107 free_page((unsigned long)rsv);
1112 * The memremap() call above assumes that a linux_efi_memreserve entry
1113 * never crosses a page boundary, so let's ensure that this remains true
1114 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1115 * using SZ_4K explicitly in the size calculation below.
1117 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1118 atomic_set(&rsv->count, 1);
1119 rsv->entry[0].base = addr;
1120 rsv->entry[0].size = size;
1122 spin_lock(&efi_mem_reserve_persistent_lock);
1123 rsv->next = efi_memreserve_root->next;
1124 efi_memreserve_root->next = __pa(rsv);
1125 spin_unlock(&efi_mem_reserve_persistent_lock);
1127 return efi_mem_reserve_iomem(addr, size);
1130 static int __init efi_memreserve_root_init(void)
1132 if (efi_memreserve_root)
1134 if (efi_memreserve_map_root())
1135 efi_memreserve_root = (void *)ULONG_MAX;
1138 early_initcall(efi_memreserve_root_init);
1141 static int update_efi_random_seed(struct notifier_block *nb,
1142 unsigned long code, void *unused)
1144 struct linux_efi_random_seed *seed;
1147 if (!kexec_in_progress)
1150 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1152 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1155 pr_err("Could not map UEFI random seed!\n");
1158 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1162 get_random_bytes(seed->bits, seed->size);
1165 pr_err("Could not map UEFI random seed!\n");
1171 static struct notifier_block efi_random_seed_nb = {
1172 .notifier_call = update_efi_random_seed,
1175 static int __init register_update_efi_random_seed(void)
1177 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1179 return register_reboot_notifier(&efi_random_seed_nb);
1181 late_initcall(register_update_efi_random_seed);