// SPDX-License-Identifier: GPL-2.0-only /* * efi.c - EFI subsystem * * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> * Copyright (C) 2013 Tom Gundersen <teg@jklm.no> * * This code registers /sys/firmware/efi{,/efivars} when EFI is supported, * allowing the efivarfs to be mounted or the efivars module to be loaded. * The existance of /sys/firmware/efi may also be used by userspace to * determine that the system supports EFI. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/kobject.h> #include <linux/module.h> #include <linux/init.h> #include <linux/device.h> #include <linux/efi.h> #include <linux/of.h> #include <linux/of_fdt.h> #include <linux/io.h> #include <linux/kexec.h> #include <linux/platform_device.h> #include <linux/random.h> #include <linux/reboot.h> #include <linux/slab.h> #include <linux/acpi.h> #include <linux/ucs2_string.h> #include <linux/memblock.h> #include <linux/security.h> #include <asm/early_ioremap.h> struct efi __read_mostly efi = { .mps = EFI_INVALID_TABLE_ADDR, .acpi = EFI_INVALID_TABLE_ADDR, .acpi20 = EFI_INVALID_TABLE_ADDR, .smbios = EFI_INVALID_TABLE_ADDR, .smbios3 = EFI_INVALID_TABLE_ADDR, .boot_info = EFI_INVALID_TABLE_ADDR, .hcdp = EFI_INVALID_TABLE_ADDR, .uga = EFI_INVALID_TABLE_ADDR, .fw_vendor = EFI_INVALID_TABLE_ADDR, .runtime = EFI_INVALID_TABLE_ADDR, .config_table = EFI_INVALID_TABLE_ADDR, .esrt = EFI_INVALID_TABLE_ADDR, .properties_table = EFI_INVALID_TABLE_ADDR, .mem_attr_table = EFI_INVALID_TABLE_ADDR, .rng_seed = EFI_INVALID_TABLE_ADDR, .tpm_log = EFI_INVALID_TABLE_ADDR, .tpm_final_log = EFI_INVALID_TABLE_ADDR, .mem_reserve = EFI_INVALID_TABLE_ADDR, }; EXPORT_SYMBOL(efi); struct mm_struct efi_mm = { .mm_rb = RB_ROOT, .mm_users = ATOMIC_INIT(2), .mm_count = ATOMIC_INIT(1), .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0}, }; struct workqueue_struct *efi_rts_wq; static bool disable_runtime; static int __init setup_noefi(char *arg) { disable_runtime = true; return 0; } early_param("noefi", setup_noefi); bool efi_runtime_disabled(void) { return disable_runtime; } static int __init parse_efi_cmdline(char *str) { if (!str) { pr_warn("need at least one option\n"); return -EINVAL; } if (parse_option_str(str, "debug")) set_bit(EFI_DBG, &efi.flags); if (parse_option_str(str, "noruntime")) disable_runtime = true; return 0; } early_param("efi", parse_efi_cmdline); struct kobject *efi_kobj; /* * Let's not leave out systab information that snuck into * the efivars driver * Note, do not add more fields in systab sysfs file as it breaks sysfs * one value per file rule! */ static ssize_t systab_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { char *str = buf; if (!kobj || !buf) return -EINVAL; if (efi.mps != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "MPS=0x%lx\n", efi.mps); if (efi.acpi20 != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20); if (efi.acpi != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "ACPI=0x%lx\n", efi.acpi); /* * If both SMBIOS and SMBIOS3 entry points are implemented, the * SMBIOS3 entry point shall be preferred, so we list it first to * let applications stop parsing after the first match. */ if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3); if (efi.smbios != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios); if (efi.hcdp != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp); if (efi.boot_info != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info); if (efi.uga != EFI_INVALID_TABLE_ADDR) str += sprintf(str, "UGA=0x%lx\n", efi.uga); return str - buf; } static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400); #define EFI_FIELD(var) efi.var #define EFI_ATTR_SHOW(name) \ static ssize_t name##_show(struct kobject *kobj, \ struct kobj_attribute *attr, char *buf) \ { \ return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \ } EFI_ATTR_SHOW(fw_vendor); EFI_ATTR_SHOW(runtime); EFI_ATTR_SHOW(config_table); static ssize_t fw_platform_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); } static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor); static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime); static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table); static struct kobj_attribute efi_attr_fw_platform_size = __ATTR_RO(fw_platform_size); static struct attribute *efi_subsys_attrs[] = { &efi_attr_systab.attr, &efi_attr_fw_vendor.attr, &efi_attr_runtime.attr, &efi_attr_config_table.attr, &efi_attr_fw_platform_size.attr, NULL, }; static umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n) { if (attr == &efi_attr_fw_vendor.attr) { if (efi_enabled(EFI_PARAVIRT) || efi.fw_vendor == EFI_INVALID_TABLE_ADDR) return 0; } else if (attr == &efi_attr_runtime.attr) { if (efi.runtime == EFI_INVALID_TABLE_ADDR) return 0; } else if (attr == &efi_attr_config_table.attr) { if (efi.config_table == EFI_INVALID_TABLE_ADDR) return 0; } return attr->mode; } static const struct attribute_group efi_subsys_attr_group = { .attrs = efi_subsys_attrs, .is_visible = efi_attr_is_visible, }; static struct efivars generic_efivars; static struct efivar_operations generic_ops; static int generic_ops_register(void) { generic_ops.get_variable = efi.get_variable; generic_ops.set_variable = efi.set_variable; generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking; generic_ops.get_next_variable = efi.get_next_variable; generic_ops.query_variable_store = efi_query_variable_store; return efivars_register(&generic_efivars, &generic_ops, efi_kobj); } static void generic_ops_unregister(void) { efivars_unregister(&generic_efivars); } #if IS_ENABLED(CONFIG_ACPI) #define EFIVAR_SSDT_NAME_MAX 16 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; static int __init efivar_ssdt_setup(char *str) { int ret = security_locked_down(LOCKDOWN_ACPI_TABLES); if (ret) return ret; if (strlen(str) < sizeof(efivar_ssdt)) memcpy(efivar_ssdt, str, strlen(str)); else pr_warn("efivar_ssdt: name too long: %s\n", str); return 0; } __setup("efivar_ssdt=", efivar_ssdt_setup); static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor, unsigned long name_size, void *data) { struct efivar_entry *entry; struct list_head *list = data; char utf8_name[EFIVAR_SSDT_NAME_MAX]; int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size); ucs2_as_utf8(utf8_name, name, limit - 1); if (strncmp(utf8_name, efivar_ssdt, limit) != 0) return 0; entry = kmalloc(sizeof(*entry), GFP_KERNEL); if (!entry) return 0; memcpy(entry->var.VariableName, name, name_size); memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t)); efivar_entry_add(entry, list); return 0; } static __init int efivar_ssdt_load(void) { LIST_HEAD(entries); struct efivar_entry *entry, *aux; unsigned long size; void *data; int ret; ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries); list_for_each_entry_safe(entry, aux, &entries, list) { pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &entry->var.VendorGuid); list_del(&entry->list); ret = efivar_entry_size(entry, &size); if (ret) { pr_err("failed to get var size\n"); goto free_entry; } data = kmalloc(size, GFP_KERNEL); if (!data) { ret = -ENOMEM; goto free_entry; } ret = efivar_entry_get(entry, NULL, &size, data); if (ret) { pr_err("failed to get var data\n"); goto free_data; } ret = acpi_load_table(data); if (ret) { pr_err("failed to load table: %d\n", ret); goto free_data; } goto free_entry; free_data: kfree(data); free_entry: kfree(entry); } return ret; } #else static inline int efivar_ssdt_load(void) { return 0; } #endif /* * We register the efi subsystem with the firmware subsystem and the * efivars subsystem with the efi subsystem, if the system was booted with * EFI. */ static int __init efisubsys_init(void) { int error; if (!efi_enabled(EFI_BOOT)) return 0; /* * Since we process only one efi_runtime_service() at a time, an * ordered workqueue (which creates only one execution context) * should suffice all our needs. */ efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0); if (!efi_rts_wq) { pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n"); clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return 0; } /* We register the efi directory at /sys/firmware/efi */ efi_kobj = kobject_create_and_add("efi", firmware_kobj); if (!efi_kobj) { pr_err("efi: Firmware registration failed.\n"); return -ENOMEM; } error = generic_ops_register(); if (error) goto err_put; if (efi_enabled(EFI_RUNTIME_SERVICES)) efivar_ssdt_load(); error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); if (error) { pr_err("efi: Sysfs attribute export failed with error %d.\n", error); goto err_unregister; } error = efi_runtime_map_init(efi_kobj); if (error) goto err_remove_group; /* and the standard mountpoint for efivarfs */ error = sysfs_create_mount_point(efi_kobj, "efivars"); if (error) { pr_err("efivars: Subsystem registration failed.\n"); goto err_remove_group; } return 0; err_remove_group: sysfs_remove_group(efi_kobj, &efi_subsys_attr_group); err_unregister: generic_ops_unregister(); err_put: kobject_put(efi_kobj); return error; } subsys_initcall(efisubsys_init); /* * Find the efi memory descriptor for a given physical address. Given a * physical address, determine if it exists within an EFI Memory Map entry, * and if so, populate the supplied memory descriptor with the appropriate * data. */ int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md) { efi_memory_desc_t *md; if (!efi_enabled(EFI_MEMMAP)) { pr_err_once("EFI_MEMMAP is not enabled.\n"); return -EINVAL; } if (!out_md) { pr_err_once("out_md is null.\n"); return -EINVAL; } for_each_efi_memory_desc(md) { u64 size; u64 end; size = md->num_pages << EFI_PAGE_SHIFT; end = md->phys_addr + size; if (phys_addr >= md->phys_addr && phys_addr < end) { memcpy(out_md, md, sizeof(*out_md)); return 0; } } return -ENOENT; } /* * Calculate the highest address of an efi memory descriptor. */ u64 __init efi_mem_desc_end(efi_memory_desc_t *md) { u64 size = md->num_pages << EFI_PAGE_SHIFT; u64 end = md->phys_addr + size; return end; } void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {} /** * efi_mem_reserve - Reserve an EFI memory region * @addr: Physical address to reserve * @size: Size of reservation * * Mark a region as reserved from general kernel allocation and * prevent it being released by efi_free_boot_services(). * * This function should be called drivers once they've parsed EFI * configuration tables to figure out where their data lives, e.g. * efi_esrt_init(). */ void __init efi_mem_reserve(phys_addr_t addr, u64 size) { if (!memblock_is_region_reserved(addr, size)) memblock_reserve(addr, size); /* * Some architectures (x86) reserve all boot services ranges * until efi_free_boot_services() because of buggy firmware * implementations. This means the above memblock_reserve() is * superfluous on x86 and instead what it needs to do is * ensure the @start, @size is not freed. */ efi_arch_mem_reserve(addr, size); } static __initdata efi_config_table_type_t common_tables[] = { {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20}, {ACPI_TABLE_GUID, "ACPI", &efi.acpi}, {HCDP_TABLE_GUID, "HCDP", &efi.hcdp}, {MPS_TABLE_GUID, "MPS", &efi.mps}, {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios}, {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3}, {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga}, {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt}, {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table}, {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table}, {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed}, {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log}, {LINUX_EFI_TPM_FINAL_LOG_GUID, "TPMFinalLog", &efi.tpm_final_log}, {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve}, #ifdef CONFIG_EFI_RCI2_TABLE {DELLEMC_EFI_RCI2_TABLE_GUID, NULL, &rci2_table_phys}, #endif {NULL_GUID, NULL, NULL}, }; static __init int match_config_table(efi_guid_t *guid, unsigned long table, efi_config_table_type_t *table_types) { int i; if (table_types) { for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) { if (!efi_guidcmp(*guid, table_types[i].guid)) { *(table_types[i].ptr) = table; if (table_types[i].name) pr_cont(" %s=0x%lx ", table_types[i].name, table); return 1; } } } return 0; } int __init efi_config_parse_tables(void *config_tables, int count, int sz, efi_config_table_type_t *arch_tables) { void *tablep; int i; tablep = config_tables; pr_info(""); for (i = 0; i < count; i++) { efi_guid_t guid; unsigned long table; if (efi_enabled(EFI_64BIT)) { u64 table64; guid = ((efi_config_table_64_t *)tablep)->guid; table64 = ((efi_config_table_64_t *)tablep)->table; table = table64; #ifndef CONFIG_64BIT if (table64 >> 32) { pr_cont("\n"); pr_err("Table located above 4GB, disabling EFI.\n"); return -EINVAL; } #endif } else { guid = ((efi_config_table_32_t *)tablep)->guid; table = ((efi_config_table_32_t *)tablep)->table; } if (!match_config_table(&guid, table, common_tables)) match_config_table(&guid, table, arch_tables); tablep += sz; } pr_cont("\n"); set_bit(EFI_CONFIG_TABLES, &efi.flags); if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) { struct linux_efi_random_seed *seed; u32 size = 0; seed = early_memremap(efi.rng_seed, sizeof(*seed)); if (seed != NULL) { size = seed->size; early_memunmap(seed, sizeof(*seed)); } else { pr_err("Could not map UEFI random seed!\n"); } if (size > 0) { seed = early_memremap(efi.rng_seed, sizeof(*seed) + size); if (seed != NULL) { pr_notice("seeding entropy pool\n"); add_device_randomness(seed->bits, seed->size); early_memunmap(seed, sizeof(*seed) + size); } else { pr_err("Could not map UEFI random seed!\n"); } } } if (efi_enabled(EFI_MEMMAP)) efi_memattr_init(); efi_tpm_eventlog_init(); /* Parse the EFI Properties table if it exists */ if (efi.properties_table != EFI_INVALID_TABLE_ADDR) { efi_properties_table_t *tbl; tbl = early_memremap(efi.properties_table, sizeof(*tbl)); if (tbl == NULL) { pr_err("Could not map Properties table!\n"); return -ENOMEM; } if (tbl->memory_protection_attribute & EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA) set_bit(EFI_NX_PE_DATA, &efi.flags); early_memunmap(tbl, sizeof(*tbl)); } if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) { unsigned long prsv = efi.mem_reserve; while (prsv) { struct linux_efi_memreserve *rsv; u8 *p; int i; /* * Just map a full page: that is what we will get * anyway, and it permits us to map the entire entry * before knowing its size. */ p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE), PAGE_SIZE); if (p == NULL) { pr_err("Could not map UEFI memreserve entry!\n"); return -ENOMEM; } rsv = (void *)(p + prsv % PAGE_SIZE); /* reserve the entry itself */ memblock_reserve(prsv, EFI_MEMRESERVE_SIZE(rsv->size)); for (i = 0; i < atomic_read(&rsv->count); i++) { memblock_reserve(rsv->entry[i].base, rsv->entry[i].size); } prsv = rsv->next; early_memunmap(p, PAGE_SIZE); } } return 0; } int __init efi_config_init(efi_config_table_type_t *arch_tables) { void *config_tables; int sz, ret; if (efi.systab->nr_tables == 0) return 0; if (efi_enabled(EFI_64BIT)) sz = sizeof(efi_config_table_64_t); else sz = sizeof(efi_config_table_32_t); /* * Let's see what config tables the firmware passed to us. */ config_tables = early_memremap(efi.systab->tables, efi.systab->nr_tables * sz); if (config_tables == NULL) { pr_err("Could not map Configuration table!\n"); return -ENOMEM; } ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz, arch_tables); early_memunmap(config_tables, efi.systab->nr_tables * sz); return ret; } #ifdef CONFIG_EFI_VARS_MODULE static int __init efi_load_efivars(void) { struct platform_device *pdev; if (!efi_enabled(EFI_RUNTIME_SERVICES)) return 0; pdev = platform_device_register_simple("efivars", 0, NULL, 0); return PTR_ERR_OR_ZERO(pdev); } device_initcall(efi_load_efivars); #endif #ifdef CONFIG_EFI_PARAMS_FROM_FDT #define UEFI_PARAM(name, prop, field) \ { \ { name }, \ { prop }, \ offsetof(struct efi_fdt_params, field), \ FIELD_SIZEOF(struct efi_fdt_params, field) \ } struct params { const char name[32]; const char propname[32]; int offset; int size; }; static __initdata struct params fdt_params[] = { UEFI_PARAM("System Table", "linux,uefi-system-table", system_table), UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap), UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size), UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size), UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver) }; static __initdata struct params xen_fdt_params[] = { UEFI_PARAM("System Table", "xen,uefi-system-table", system_table), UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap), UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size), UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size), UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver) }; #define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params) static __initdata struct { const char *uname; const char *subnode; struct params *params; } dt_params[] = { { "hypervisor", "uefi", xen_fdt_params }, { "chosen", NULL, fdt_params }, }; struct param_info { int found; void *params; const char *missing; }; static int __init __find_uefi_params(unsigned long node, struct param_info *info, struct params *params) { const void *prop; void *dest; u64 val; int i, len; for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) { prop = of_get_flat_dt_prop(node, params[i].propname, &len); if (!prop) { info->missing = params[i].name; return 0; } dest = info->params + params[i].offset; info->found++; val = of_read_number(prop, len / sizeof(u32)); if (params[i].size == sizeof(u32)) *(u32 *)dest = val; else *(u64 *)dest = val; if (efi_enabled(EFI_DBG)) pr_info(" %s: 0x%0*llx\n", params[i].name, params[i].size * 2, val); } return 1; } static int __init fdt_find_uefi_params(unsigned long node, const char *uname, int depth, void *data) { struct param_info *info = data; int i; for (i = 0; i < ARRAY_SIZE(dt_params); i++) { const char *subnode = dt_params[i].subnode; if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) { info->missing = dt_params[i].params[0].name; continue; } if (subnode) { int err = of_get_flat_dt_subnode_by_name(node, subnode); if (err < 0) return 0; node = err; } return __find_uefi_params(node, info, dt_params[i].params); } return 0; } int __init efi_get_fdt_params(struct efi_fdt_params *params) { struct param_info info; int ret; pr_info("Getting EFI parameters from FDT:\n"); info.found = 0; info.params = params; ret = of_scan_flat_dt(fdt_find_uefi_params, &info); if (!info.found) pr_info("UEFI not found.\n"); else if (!ret) pr_err("Can't find '%s' in device tree!\n", info.missing); return ret; } #endif /* CONFIG_EFI_PARAMS_FROM_FDT */ static __initdata char memory_type_name[][20] = { "Reserved", "Loader Code", "Loader Data", "Boot Code", "Boot Data", "Runtime Code", "Runtime Data", "Conventional Memory", "Unusable Memory", "ACPI Reclaim Memory", "ACPI Memory NVS", "Memory Mapped I/O", "MMIO Port Space", "PAL Code", "Persistent Memory", }; char * __init efi_md_typeattr_format(char *buf, size_t size, const efi_memory_desc_t *md) { char *pos; int type_len; u64 attr; pos = buf; if (md->type >= ARRAY_SIZE(memory_type_name)) type_len = snprintf(pos, size, "[type=%u", md->type); else type_len = snprintf(pos, size, "[%-*s", (int)(sizeof(memory_type_name[0]) - 1), memory_type_name[md->type]); if (type_len >= size) return buf; pos += type_len; size -= type_len; attr = md->attribute; if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO | EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP | EFI_MEMORY_NV | EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE)) snprintf(pos, size, "|attr=0x%016llx]", (unsigned long long)attr); else snprintf(pos, size, "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", attr & EFI_MEMORY_RUNTIME ? "RUN" : "", attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "", attr & EFI_MEMORY_NV ? "NV" : "", attr & EFI_MEMORY_XP ? "XP" : "", attr & EFI_MEMORY_RP ? "RP" : "", attr & EFI_MEMORY_WP ? "WP" : "", attr & EFI_MEMORY_RO ? "RO" : "", attr & EFI_MEMORY_UCE ? "UCE" : "", attr & EFI_MEMORY_WB ? "WB" : "", attr & EFI_MEMORY_WT ? "WT" : "", attr & EFI_MEMORY_WC ? "WC" : "", attr & EFI_MEMORY_UC ? "UC" : ""); return buf; } /* * IA64 has a funky EFI memory map that doesn't work the same way as * other architectures. */ #ifndef CONFIG_IA64 /* * efi_mem_attributes - lookup memmap attributes for physical address * @phys_addr: the physical address to lookup * * Search in the EFI memory map for the region covering * @phys_addr. Returns the EFI memory attributes if the region * was found in the memory map, 0 otherwise. */ u64 efi_mem_attributes(unsigned long phys_addr) { efi_memory_desc_t *md; if (!efi_enabled(EFI_MEMMAP)) return 0; for_each_efi_memory_desc(md) { if ((md->phys_addr <= phys_addr) && (phys_addr < (md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)))) return md->attribute; } return 0; } /* * efi_mem_type - lookup memmap type for physical address * @phys_addr: the physical address to lookup * * Search in the EFI memory map for the region covering @phys_addr. * Returns the EFI memory type if the region was found in the memory * map, EFI_RESERVED_TYPE (zero) otherwise. */ int efi_mem_type(unsigned long phys_addr) { const efi_memory_desc_t *md; if (!efi_enabled(EFI_MEMMAP)) return -ENOTSUPP; for_each_efi_memory_desc(md) { if ((md->phys_addr <= phys_addr) && (phys_addr < (md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)))) return md->type; } return -EINVAL; } #endif int efi_status_to_err(efi_status_t status) { int err; switch (status) { case EFI_SUCCESS: err = 0; break; case EFI_INVALID_PARAMETER: err = -EINVAL; break; case EFI_OUT_OF_RESOURCES: err = -ENOSPC; break; case EFI_DEVICE_ERROR: err = -EIO; break; case EFI_WRITE_PROTECTED: err = -EROFS; break; case EFI_SECURITY_VIOLATION: err = -EACCES; break; case EFI_NOT_FOUND: err = -ENOENT; break; case EFI_ABORTED: err = -EINTR; break; default: err = -EINVAL; } return err; } static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; static int __init efi_memreserve_map_root(void) { if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) return -ENODEV; efi_memreserve_root = memremap(efi.mem_reserve, sizeof(*efi_memreserve_root), MEMREMAP_WB); if (WARN_ON_ONCE(!efi_memreserve_root)) return -ENOMEM; return 0; } int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { struct linux_efi_memreserve *rsv; unsigned long prsv; int rc, index; if (efi_memreserve_root == (void *)ULONG_MAX) return -ENODEV; if (!efi_memreserve_root) { rc = efi_memreserve_map_root(); if (rc) return rc; } /* first try to find a slot in an existing linked list entry */ for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) { rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB); index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size); if (index < rsv->size) { rsv->entry[index].base = addr; rsv->entry[index].size = size; memunmap(rsv); return 0; } memunmap(rsv); } /* no slot found - allocate a new linked list entry */ rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC); if (!rsv) return -ENOMEM; /* * The memremap() call above assumes that a linux_efi_memreserve entry * never crosses a page boundary, so let's ensure that this remains true * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by * using SZ_4K explicitly in the size calculation below. */ rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K); atomic_set(&rsv->count, 1); rsv->entry[0].base = addr; rsv->entry[0].size = size; spin_lock(&efi_mem_reserve_persistent_lock); rsv->next = efi_memreserve_root->next; efi_memreserve_root->next = __pa(rsv); spin_unlock(&efi_mem_reserve_persistent_lock); return 0; } static int __init efi_memreserve_root_init(void) { if (efi_memreserve_root) return 0; if (efi_memreserve_map_root()) efi_memreserve_root = (void *)ULONG_MAX; return 0; } early_initcall(efi_memreserve_root_init); #ifdef CONFIG_KEXEC static int update_efi_random_seed(struct notifier_block *nb, unsigned long code, void *unused) { struct linux_efi_random_seed *seed; u32 size = 0; if (!kexec_in_progress) return NOTIFY_DONE; seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB); if (seed != NULL) { size = min(seed->size, EFI_RANDOM_SEED_SIZE); memunmap(seed); } else { pr_err("Could not map UEFI random seed!\n"); } if (size > 0) { seed = memremap(efi.rng_seed, sizeof(*seed) + size, MEMREMAP_WB); if (seed != NULL) { seed->size = size; get_random_bytes(seed->bits, seed->size); memunmap(seed); } else { pr_err("Could not map UEFI random seed!\n"); } } return NOTIFY_DONE; } static struct notifier_block efi_random_seed_nb = { .notifier_call = update_efi_random_seed, }; static int register_update_efi_random_seed(void) { if (efi.rng_seed == EFI_INVALID_TABLE_ADDR) return 0; return register_reboot_notifier(&efi_random_seed_nb); } late_initcall(register_update_efi_random_seed); #endif