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/device.h>
21 #include <linux/efi.h>
23 #include <linux/of_fdt.h>
25 #include <linux/kexec.h>
26 #include <linux/platform_device.h>
27 #include <linux/random.h>
28 #include <linux/reboot.h>
29 #include <linux/slab.h>
30 #include <linux/acpi.h>
31 #include <linux/ucs2_string.h>
32 #include <linux/memblock.h>
33 #include <linux/security.h>
35 #include <asm/early_ioremap.h>
37 struct efi __read_mostly efi = {
38 .mps = EFI_INVALID_TABLE_ADDR,
39 .acpi = EFI_INVALID_TABLE_ADDR,
40 .acpi20 = EFI_INVALID_TABLE_ADDR,
41 .smbios = EFI_INVALID_TABLE_ADDR,
42 .smbios3 = EFI_INVALID_TABLE_ADDR,
43 .boot_info = EFI_INVALID_TABLE_ADDR,
44 .hcdp = EFI_INVALID_TABLE_ADDR,
45 .uga = EFI_INVALID_TABLE_ADDR,
46 .fw_vendor = EFI_INVALID_TABLE_ADDR,
47 .runtime = EFI_INVALID_TABLE_ADDR,
48 .config_table = EFI_INVALID_TABLE_ADDR,
49 .esrt = EFI_INVALID_TABLE_ADDR,
50 .properties_table = EFI_INVALID_TABLE_ADDR,
51 .mem_attr_table = EFI_INVALID_TABLE_ADDR,
52 .rng_seed = EFI_INVALID_TABLE_ADDR,
53 .tpm_log = EFI_INVALID_TABLE_ADDR,
54 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
55 .mem_reserve = EFI_INVALID_TABLE_ADDR,
59 struct mm_struct efi_mm = {
61 .mm_users = ATOMIC_INIT(2),
62 .mm_count = ATOMIC_INIT(1),
63 .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
64 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
65 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
66 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
69 struct workqueue_struct *efi_rts_wq;
71 static bool disable_runtime;
72 static int __init setup_noefi(char *arg)
74 disable_runtime = true;
77 early_param("noefi", setup_noefi);
79 bool efi_runtime_disabled(void)
81 return disable_runtime;
84 bool __pure __efi_soft_reserve_enabled(void)
86 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
89 static int __init parse_efi_cmdline(char *str)
92 pr_warn("need at least one option\n");
96 if (parse_option_str(str, "debug"))
97 set_bit(EFI_DBG, &efi.flags);
99 if (parse_option_str(str, "noruntime"))
100 disable_runtime = true;
102 if (parse_option_str(str, "nosoftreserve"))
103 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
107 early_param("efi", parse_efi_cmdline);
109 struct kobject *efi_kobj;
112 * Let's not leave out systab information that snuck into
114 * Note, do not add more fields in systab sysfs file as it breaks sysfs
115 * one value per file rule!
117 static ssize_t systab_show(struct kobject *kobj,
118 struct kobj_attribute *attr, char *buf)
125 if (efi.mps != EFI_INVALID_TABLE_ADDR)
126 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
127 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
128 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
129 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
130 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
132 * If both SMBIOS and SMBIOS3 entry points are implemented, the
133 * SMBIOS3 entry point shall be preferred, so we list it first to
134 * let applications stop parsing after the first match.
136 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
137 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
138 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
139 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
140 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
141 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
142 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
143 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
144 if (efi.uga != EFI_INVALID_TABLE_ADDR)
145 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
150 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
152 #define EFI_FIELD(var) efi.var
154 #define EFI_ATTR_SHOW(name) \
155 static ssize_t name##_show(struct kobject *kobj, \
156 struct kobj_attribute *attr, char *buf) \
158 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
161 EFI_ATTR_SHOW(fw_vendor);
162 EFI_ATTR_SHOW(runtime);
163 EFI_ATTR_SHOW(config_table);
165 static ssize_t fw_platform_size_show(struct kobject *kobj,
166 struct kobj_attribute *attr, char *buf)
168 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
171 static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
172 static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
173 static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
174 static struct kobj_attribute efi_attr_fw_platform_size =
175 __ATTR_RO(fw_platform_size);
177 static struct attribute *efi_subsys_attrs[] = {
178 &efi_attr_systab.attr,
179 &efi_attr_fw_vendor.attr,
180 &efi_attr_runtime.attr,
181 &efi_attr_config_table.attr,
182 &efi_attr_fw_platform_size.attr,
186 static umode_t efi_attr_is_visible(struct kobject *kobj,
187 struct attribute *attr, int n)
189 if (attr == &efi_attr_fw_vendor.attr) {
190 if (efi_enabled(EFI_PARAVIRT) ||
191 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
193 } else if (attr == &efi_attr_runtime.attr) {
194 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
196 } else if (attr == &efi_attr_config_table.attr) {
197 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
204 static const struct attribute_group efi_subsys_attr_group = {
205 .attrs = efi_subsys_attrs,
206 .is_visible = efi_attr_is_visible,
209 static struct efivars generic_efivars;
210 static struct efivar_operations generic_ops;
212 static int generic_ops_register(void)
214 generic_ops.get_variable = efi.get_variable;
215 generic_ops.set_variable = efi.set_variable;
216 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
217 generic_ops.get_next_variable = efi.get_next_variable;
218 generic_ops.query_variable_store = efi_query_variable_store;
220 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
223 static void generic_ops_unregister(void)
225 efivars_unregister(&generic_efivars);
228 #if IS_ENABLED(CONFIG_ACPI)
229 #define EFIVAR_SSDT_NAME_MAX 16
230 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
231 static int __init efivar_ssdt_setup(char *str)
233 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
238 if (strlen(str) < sizeof(efivar_ssdt))
239 memcpy(efivar_ssdt, str, strlen(str));
241 pr_warn("efivar_ssdt: name too long: %s\n", str);
244 __setup("efivar_ssdt=", efivar_ssdt_setup);
246 static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
247 unsigned long name_size, void *data)
249 struct efivar_entry *entry;
250 struct list_head *list = data;
251 char utf8_name[EFIVAR_SSDT_NAME_MAX];
252 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
254 ucs2_as_utf8(utf8_name, name, limit - 1);
255 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
258 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
262 memcpy(entry->var.VariableName, name, name_size);
263 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
265 efivar_entry_add(entry, list);
270 static __init int efivar_ssdt_load(void)
273 struct efivar_entry *entry, *aux;
281 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
283 list_for_each_entry_safe(entry, aux, &entries, list) {
284 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
285 &entry->var.VendorGuid);
287 list_del(&entry->list);
289 ret = efivar_entry_size(entry, &size);
291 pr_err("failed to get var size\n");
295 data = kmalloc(size, GFP_KERNEL);
301 ret = efivar_entry_get(entry, NULL, &size, data);
303 pr_err("failed to get var data\n");
307 ret = acpi_load_table(data, NULL);
309 pr_err("failed to load table: %d\n", ret);
325 static inline int efivar_ssdt_load(void) { return 0; }
329 * We register the efi subsystem with the firmware subsystem and the
330 * efivars subsystem with the efi subsystem, if the system was booted with
333 static int __init efisubsys_init(void)
337 if (!efi_enabled(EFI_BOOT))
341 * Since we process only one efi_runtime_service() at a time, an
342 * ordered workqueue (which creates only one execution context)
343 * should suffice all our needs.
345 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
347 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
348 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
352 /* We register the efi directory at /sys/firmware/efi */
353 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
355 pr_err("efi: Firmware registration failed.\n");
359 error = generic_ops_register();
363 if (efi_enabled(EFI_RUNTIME_SERVICES))
366 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
368 pr_err("efi: Sysfs attribute export failed with error %d.\n",
373 error = efi_runtime_map_init(efi_kobj);
375 goto err_remove_group;
377 /* and the standard mountpoint for efivarfs */
378 error = sysfs_create_mount_point(efi_kobj, "efivars");
380 pr_err("efivars: Subsystem registration failed.\n");
381 goto err_remove_group;
387 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
389 generic_ops_unregister();
391 kobject_put(efi_kobj);
395 subsys_initcall(efisubsys_init);
398 * Find the efi memory descriptor for a given physical address. Given a
399 * physical address, determine if it exists within an EFI Memory Map entry,
400 * and if so, populate the supplied memory descriptor with the appropriate
403 int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
405 efi_memory_desc_t *md;
407 if (!efi_enabled(EFI_MEMMAP)) {
408 pr_err_once("EFI_MEMMAP is not enabled.\n");
413 pr_err_once("out_md is null.\n");
417 for_each_efi_memory_desc(md) {
421 size = md->num_pages << EFI_PAGE_SHIFT;
422 end = md->phys_addr + size;
423 if (phys_addr >= md->phys_addr && phys_addr < end) {
424 memcpy(out_md, md, sizeof(*out_md));
432 * Calculate the highest address of an efi memory descriptor.
434 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
436 u64 size = md->num_pages << EFI_PAGE_SHIFT;
437 u64 end = md->phys_addr + size;
441 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
444 * efi_mem_reserve - Reserve an EFI memory region
445 * @addr: Physical address to reserve
446 * @size: Size of reservation
448 * Mark a region as reserved from general kernel allocation and
449 * prevent it being released by efi_free_boot_services().
451 * This function should be called drivers once they've parsed EFI
452 * configuration tables to figure out where their data lives, e.g.
455 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
457 if (!memblock_is_region_reserved(addr, size))
458 memblock_reserve(addr, size);
461 * Some architectures (x86) reserve all boot services ranges
462 * until efi_free_boot_services() because of buggy firmware
463 * implementations. This means the above memblock_reserve() is
464 * superfluous on x86 and instead what it needs to do is
465 * ensure the @start, @size is not freed.
467 efi_arch_mem_reserve(addr, size);
470 static __initdata efi_config_table_type_t common_tables[] = {
471 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
472 {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
473 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
474 {MPS_TABLE_GUID, "MPS", &efi.mps},
475 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
476 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
477 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
478 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
479 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
480 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
481 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
482 {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log},
483 {LINUX_EFI_TPM_FINAL_LOG_GUID, "TPMFinalLog", &efi.tpm_final_log},
484 {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve},
485 #ifdef CONFIG_EFI_RCI2_TABLE
486 {DELLEMC_EFI_RCI2_TABLE_GUID, NULL, &rci2_table_phys},
488 {NULL_GUID, NULL, NULL},
491 static __init int match_config_table(efi_guid_t *guid,
493 efi_config_table_type_t *table_types)
498 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
499 if (!efi_guidcmp(*guid, table_types[i].guid)) {
500 *(table_types[i].ptr) = table;
501 if (table_types[i].name)
502 pr_cont(" %s=0x%lx ",
503 table_types[i].name, table);
512 int __init efi_config_parse_tables(void *config_tables, int count, int sz,
513 efi_config_table_type_t *arch_tables)
518 tablep = config_tables;
520 for (i = 0; i < count; i++) {
524 if (efi_enabled(EFI_64BIT)) {
526 guid = ((efi_config_table_64_t *)tablep)->guid;
527 table64 = ((efi_config_table_64_t *)tablep)->table;
532 pr_err("Table located above 4GB, disabling EFI.\n");
537 guid = ((efi_config_table_32_t *)tablep)->guid;
538 table = ((efi_config_table_32_t *)tablep)->table;
541 if (!match_config_table(&guid, table, common_tables))
542 match_config_table(&guid, table, arch_tables);
547 set_bit(EFI_CONFIG_TABLES, &efi.flags);
549 if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
550 struct linux_efi_random_seed *seed;
553 seed = early_memremap(efi.rng_seed, sizeof(*seed));
556 early_memunmap(seed, sizeof(*seed));
558 pr_err("Could not map UEFI random seed!\n");
561 seed = early_memremap(efi.rng_seed,
562 sizeof(*seed) + size);
564 pr_notice("seeding entropy pool\n");
565 add_bootloader_randomness(seed->bits, seed->size);
566 early_memunmap(seed, sizeof(*seed) + size);
568 pr_err("Could not map UEFI random seed!\n");
573 if (efi_enabled(EFI_MEMMAP))
576 efi_tpm_eventlog_init();
578 /* Parse the EFI Properties table if it exists */
579 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
580 efi_properties_table_t *tbl;
582 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
584 pr_err("Could not map Properties table!\n");
588 if (tbl->memory_protection_attribute &
589 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
590 set_bit(EFI_NX_PE_DATA, &efi.flags);
592 early_memunmap(tbl, sizeof(*tbl));
595 if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) {
596 unsigned long prsv = efi.mem_reserve;
599 struct linux_efi_memreserve *rsv;
604 * Just map a full page: that is what we will get
605 * anyway, and it permits us to map the entire entry
606 * before knowing its size.
608 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
611 pr_err("Could not map UEFI memreserve entry!\n");
615 rsv = (void *)(p + prsv % PAGE_SIZE);
617 /* reserve the entry itself */
618 memblock_reserve(prsv, EFI_MEMRESERVE_SIZE(rsv->size));
620 for (i = 0; i < atomic_read(&rsv->count); i++) {
621 memblock_reserve(rsv->entry[i].base,
626 early_memunmap(p, PAGE_SIZE);
633 int __init efi_config_init(efi_config_table_type_t *arch_tables)
638 if (efi.systab->nr_tables == 0)
641 if (efi_enabled(EFI_64BIT))
642 sz = sizeof(efi_config_table_64_t);
644 sz = sizeof(efi_config_table_32_t);
647 * Let's see what config tables the firmware passed to us.
649 config_tables = early_memremap(efi.systab->tables,
650 efi.systab->nr_tables * sz);
651 if (config_tables == NULL) {
652 pr_err("Could not map Configuration table!\n");
656 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
659 early_memunmap(config_tables, efi.systab->nr_tables * sz);
663 #ifdef CONFIG_EFI_VARS_MODULE
664 static int __init efi_load_efivars(void)
666 struct platform_device *pdev;
668 if (!efi_enabled(EFI_RUNTIME_SERVICES))
671 pdev = platform_device_register_simple("efivars", 0, NULL, 0);
672 return PTR_ERR_OR_ZERO(pdev);
674 device_initcall(efi_load_efivars);
677 #ifdef CONFIG_EFI_PARAMS_FROM_FDT
679 #define UEFI_PARAM(name, prop, field) \
683 offsetof(struct efi_fdt_params, field), \
684 sizeof_field(struct efi_fdt_params, field) \
689 const char propname[32];
694 static __initdata struct params fdt_params[] = {
695 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
696 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
697 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
698 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
699 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
702 static __initdata struct params xen_fdt_params[] = {
703 UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
704 UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
705 UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
706 UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
707 UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
710 #define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
712 static __initdata struct {
715 struct params *params;
717 { "hypervisor", "uefi", xen_fdt_params },
718 { "chosen", NULL, fdt_params },
727 static int __init __find_uefi_params(unsigned long node,
728 struct param_info *info,
729 struct params *params)
736 for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
737 prop = of_get_flat_dt_prop(node, params[i].propname, &len);
739 info->missing = params[i].name;
743 dest = info->params + params[i].offset;
746 val = of_read_number(prop, len / sizeof(u32));
748 if (params[i].size == sizeof(u32))
753 if (efi_enabled(EFI_DBG))
754 pr_info(" %s: 0x%0*llx\n", params[i].name,
755 params[i].size * 2, val);
761 static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
762 int depth, void *data)
764 struct param_info *info = data;
767 for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
768 const char *subnode = dt_params[i].subnode;
770 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
771 info->missing = dt_params[i].params[0].name;
776 int err = of_get_flat_dt_subnode_by_name(node, subnode);
784 return __find_uefi_params(node, info, dt_params[i].params);
790 int __init efi_get_fdt_params(struct efi_fdt_params *params)
792 struct param_info info;
795 pr_info("Getting EFI parameters from FDT:\n");
798 info.params = params;
800 ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
802 pr_info("UEFI not found.\n");
804 pr_err("Can't find '%s' in device tree!\n",
809 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */
811 static __initdata char memory_type_name[][20] = {
819 "Conventional Memory",
821 "ACPI Reclaim Memory",
829 char * __init efi_md_typeattr_format(char *buf, size_t size,
830 const efi_memory_desc_t *md)
837 if (md->type >= ARRAY_SIZE(memory_type_name))
838 type_len = snprintf(pos, size, "[type=%u", md->type);
840 type_len = snprintf(pos, size, "[%-*s",
841 (int)(sizeof(memory_type_name[0]) - 1),
842 memory_type_name[md->type]);
843 if (type_len >= size)
849 attr = md->attribute;
850 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
851 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
852 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
853 EFI_MEMORY_NV | EFI_MEMORY_SP |
854 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
855 snprintf(pos, size, "|attr=0x%016llx]",
856 (unsigned long long)attr);
859 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
860 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
861 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
862 attr & EFI_MEMORY_SP ? "SP" : "",
863 attr & EFI_MEMORY_NV ? "NV" : "",
864 attr & EFI_MEMORY_XP ? "XP" : "",
865 attr & EFI_MEMORY_RP ? "RP" : "",
866 attr & EFI_MEMORY_WP ? "WP" : "",
867 attr & EFI_MEMORY_RO ? "RO" : "",
868 attr & EFI_MEMORY_UCE ? "UCE" : "",
869 attr & EFI_MEMORY_WB ? "WB" : "",
870 attr & EFI_MEMORY_WT ? "WT" : "",
871 attr & EFI_MEMORY_WC ? "WC" : "",
872 attr & EFI_MEMORY_UC ? "UC" : "");
877 * IA64 has a funky EFI memory map that doesn't work the same way as
878 * other architectures.
882 * efi_mem_attributes - lookup memmap attributes for physical address
883 * @phys_addr: the physical address to lookup
885 * Search in the EFI memory map for the region covering
886 * @phys_addr. Returns the EFI memory attributes if the region
887 * was found in the memory map, 0 otherwise.
889 u64 efi_mem_attributes(unsigned long phys_addr)
891 efi_memory_desc_t *md;
893 if (!efi_enabled(EFI_MEMMAP))
896 for_each_efi_memory_desc(md) {
897 if ((md->phys_addr <= phys_addr) &&
898 (phys_addr < (md->phys_addr +
899 (md->num_pages << EFI_PAGE_SHIFT))))
900 return md->attribute;
906 * efi_mem_type - lookup memmap type for physical address
907 * @phys_addr: the physical address to lookup
909 * Search in the EFI memory map for the region covering @phys_addr.
910 * Returns the EFI memory type if the region was found in the memory
911 * map, -EINVAL otherwise.
913 int efi_mem_type(unsigned long phys_addr)
915 const efi_memory_desc_t *md;
917 if (!efi_enabled(EFI_MEMMAP))
920 for_each_efi_memory_desc(md) {
921 if ((md->phys_addr <= phys_addr) &&
922 (phys_addr < (md->phys_addr +
923 (md->num_pages << EFI_PAGE_SHIFT))))
930 int efi_status_to_err(efi_status_t status)
938 case EFI_INVALID_PARAMETER:
941 case EFI_OUT_OF_RESOURCES:
944 case EFI_DEVICE_ERROR:
947 case EFI_WRITE_PROTECTED:
950 case EFI_SECURITY_VIOLATION:
966 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
967 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
969 static int __init efi_memreserve_map_root(void)
971 if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR)
974 efi_memreserve_root = memremap(efi.mem_reserve,
975 sizeof(*efi_memreserve_root),
977 if (WARN_ON_ONCE(!efi_memreserve_root))
982 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
984 struct resource *res, *parent;
986 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
990 res->name = "reserved";
991 res->flags = IORESOURCE_MEM;
993 res->end = addr + size - 1;
995 /* we expect a conflict with a 'System RAM' region */
996 parent = request_resource_conflict(&iomem_resource, res);
997 return parent ? request_resource(parent, res) : 0;
1000 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
1002 struct linux_efi_memreserve *rsv;
1006 if (efi_memreserve_root == (void *)ULONG_MAX)
1009 if (!efi_memreserve_root) {
1010 rc = efi_memreserve_map_root();
1015 /* first try to find a slot in an existing linked list entry */
1016 for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) {
1017 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1018 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1019 if (index < rsv->size) {
1020 rsv->entry[index].base = addr;
1021 rsv->entry[index].size = size;
1024 return efi_mem_reserve_iomem(addr, size);
1029 /* no slot found - allocate a new linked list entry */
1030 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1034 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1036 free_page((unsigned long)rsv);
1041 * The memremap() call above assumes that a linux_efi_memreserve entry
1042 * never crosses a page boundary, so let's ensure that this remains true
1043 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1044 * using SZ_4K explicitly in the size calculation below.
1046 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1047 atomic_set(&rsv->count, 1);
1048 rsv->entry[0].base = addr;
1049 rsv->entry[0].size = size;
1051 spin_lock(&efi_mem_reserve_persistent_lock);
1052 rsv->next = efi_memreserve_root->next;
1053 efi_memreserve_root->next = __pa(rsv);
1054 spin_unlock(&efi_mem_reserve_persistent_lock);
1056 return efi_mem_reserve_iomem(addr, size);
1059 static int __init efi_memreserve_root_init(void)
1061 if (efi_memreserve_root)
1063 if (efi_memreserve_map_root())
1064 efi_memreserve_root = (void *)ULONG_MAX;
1067 early_initcall(efi_memreserve_root_init);
1070 static int update_efi_random_seed(struct notifier_block *nb,
1071 unsigned long code, void *unused)
1073 struct linux_efi_random_seed *seed;
1076 if (!kexec_in_progress)
1079 seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
1081 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1084 pr_err("Could not map UEFI random seed!\n");
1087 seed = memremap(efi.rng_seed, sizeof(*seed) + size,
1091 get_random_bytes(seed->bits, seed->size);
1094 pr_err("Could not map UEFI random seed!\n");
1100 static struct notifier_block efi_random_seed_nb = {
1101 .notifier_call = update_efi_random_seed,
1104 static int register_update_efi_random_seed(void)
1106 if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
1108 return register_reboot_notifier(&efi_random_seed_nb);
1110 late_initcall(register_update_efi_random_seed);