Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1182 insertions, 0 deletions

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
new file mode 100644
index 0000000000..1974f0ad32
--- /dev/null
+++ b/drivers/firmware/efi/efi.c
@@ -0,0 +1,1182 @@
+// 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/debugfs.h>
+#include <linux/device.h>
+#include <linux/efi.h>
+#include <linux/of.h>
+#include <linux/initrd.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 = {
+	.runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
+	.acpi			= EFI_INVALID_TABLE_ADDR,
+	.acpi20			= EFI_INVALID_TABLE_ADDR,
+	.smbios			= EFI_INVALID_TABLE_ADDR,
+	.smbios3		= EFI_INVALID_TABLE_ADDR,
+	.esrt			= EFI_INVALID_TABLE_ADDR,
+	.tpm_log		= EFI_INVALID_TABLE_ADDR,
+	.tpm_final_log		= EFI_INVALID_TABLE_ADDR,
+#ifdef CONFIG_LOAD_UEFI_KEYS
+	.mokvar_table		= EFI_INVALID_TABLE_ADDR,
+#endif
+#ifdef CONFIG_EFI_COCO_SECRET
+	.coco_secret		= EFI_INVALID_TABLE_ADDR,
+#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+	.unaccepted		= EFI_INVALID_TABLE_ADDR,
+#endif
+};
+EXPORT_SYMBOL(efi);
+
+unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
+static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
+static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
+static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
+
+extern unsigned long screen_info_table;
+
+struct mm_struct efi_mm = {
+	.mm_mt			= MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
+	.mm_users		= ATOMIC_INIT(2),
+	.mm_count		= ATOMIC_INIT(1),
+	.write_protect_seq      = SEQCNT_ZERO(efi_mm.write_protect_seq),
+	MMAP_LOCK_INITIALIZER(efi_mm)
+	.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 = IS_ENABLED(CONFIG_EFI_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;
+}
+
+bool __pure __efi_soft_reserve_enabled(void)
+{
+	return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
+}
+
+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;
+
+	if (parse_option_str(str, "runtime"))
+		disable_runtime = false;
+
+	if (parse_option_str(str, "nosoftreserve"))
+		set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
+
+	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.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 (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
+		str = efi_systab_show_arch(str);
+
+	return str - buf;
+}
+
+static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
+
+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);
+}
+
+extern __weak struct kobj_attribute efi_attr_fw_vendor;
+extern __weak struct kobj_attribute efi_attr_runtime;
+extern __weak struct kobj_attribute efi_attr_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_platform_size.attr,
+	&efi_attr_fw_vendor.attr,
+	&efi_attr_runtime.attr,
+	&efi_attr_config_table.attr,
+	NULL,
+};
+
+umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
+				   int n)
+{
+	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 bool generic_ops_supported(void)
+{
+	unsigned long name_size;
+	efi_status_t status;
+	efi_char16_t name;
+	efi_guid_t guid;
+
+	name_size = sizeof(name);
+
+	status = efi.get_next_variable(&name_size, &name, &guid);
+	if (status == EFI_UNSUPPORTED)
+		return false;
+
+	return true;
+}
+
+static int generic_ops_register(void)
+{
+	if (!generic_ops_supported())
+		return 0;
+
+	generic_ops.get_variable = efi.get_variable;
+	generic_ops.get_next_variable = efi.get_next_variable;
+	generic_ops.query_variable_store = efi_query_variable_store;
+	generic_ops.query_variable_info = efi.query_variable_info;
+
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
+		generic_ops.set_variable = efi.set_variable;
+		generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
+	}
+	return efivars_register(&generic_efivars, &generic_ops);
+}
+
+static void generic_ops_unregister(void)
+{
+	if (!generic_ops.get_variable)
+		return;
+
+	efivars_unregister(&generic_efivars);
+}
+
+#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
+#define EFIVAR_SSDT_NAME_MAX	16UL
+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 1;
+}
+__setup("efivar_ssdt=", efivar_ssdt_setup);
+
+static __init int efivar_ssdt_load(void)
+{
+	unsigned long name_size = 256;
+	efi_char16_t *name = NULL;
+	efi_status_t status;
+	efi_guid_t guid;
+
+	if (!efivar_ssdt[0])
+		return 0;
+
+	name = kzalloc(name_size, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
+
+	for (;;) {
+		char utf8_name[EFIVAR_SSDT_NAME_MAX];
+		unsigned long data_size = 0;
+		void *data;
+		int limit;
+
+		status = efi.get_next_variable(&name_size, name, &guid);
+		if (status == EFI_NOT_FOUND) {
+			break;
+		} else if (status == EFI_BUFFER_TOO_SMALL) {
+			efi_char16_t *name_tmp =
+				krealloc(name, name_size, GFP_KERNEL);
+			if (!name_tmp) {
+				kfree(name);
+				return -ENOMEM;
+			}
+			name = name_tmp;
+			continue;
+		}
+
+		limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
+		ucs2_as_utf8(utf8_name, name, limit - 1);
+		if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
+			continue;
+
+		pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
+
+		status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
+		if (status != EFI_BUFFER_TOO_SMALL || !data_size)
+			return -EIO;
+
+		data = kmalloc(data_size, GFP_KERNEL);
+		if (!data)
+			return -ENOMEM;
+
+		status = efi.get_variable(name, &guid, NULL, &data_size, data);
+		if (status == EFI_SUCCESS) {
+			acpi_status ret = acpi_load_table(data, NULL);
+			if (ret)
+				pr_err("failed to load table: %u\n", ret);
+			else
+				continue;
+		} else {
+			pr_err("failed to get var data: 0x%lx\n", status);
+		}
+		kfree(data);
+	}
+	return 0;
+}
+#else
+static inline int efivar_ssdt_load(void) { return 0; }
+#endif
+
+#ifdef CONFIG_DEBUG_FS
+
+#define EFI_DEBUGFS_MAX_BLOBS 32
+
+static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
+
+static void __init efi_debugfs_init(void)
+{
+	struct dentry *efi_debugfs;
+	efi_memory_desc_t *md;
+	char name[32];
+	int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
+	int i = 0;
+
+	efi_debugfs = debugfs_create_dir("efi", NULL);
+	if (IS_ERR_OR_NULL(efi_debugfs))
+		return;
+
+	for_each_efi_memory_desc(md) {
+		switch (md->type) {
+		case EFI_BOOT_SERVICES_CODE:
+			snprintf(name, sizeof(name), "boot_services_code%d",
+				 type_count[md->type]++);
+			break;
+		case EFI_BOOT_SERVICES_DATA:
+			snprintf(name, sizeof(name), "boot_services_data%d",
+				 type_count[md->type]++);
+			break;
+		default:
+			continue;
+		}
+
+		if (i >= EFI_DEBUGFS_MAX_BLOBS) {
+			pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
+				EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
+			break;
+		}
+
+		debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
+		debugfs_blob[i].data = memremap(md->phys_addr,
+						debugfs_blob[i].size,
+						MEMREMAP_WB);
+		if (!debugfs_blob[i].data)
+			continue;
+
+		debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
+		i++;
+	}
+}
+#else
+static inline void efi_debugfs_init(void) {}
+#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_RUNTIME_SERVICES))
+		efi.runtime_supported_mask = 0;
+
+	if (!efi_enabled(EFI_BOOT))
+		return 0;
+
+	if (efi.runtime_supported_mask) {
+		/*
+		 * Since we process only one efi_runtime_service() at a time, an
+		 * ordered workqueue (which creates only one execution context)
+		 * should suffice for 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);
+			efi.runtime_supported_mask = 0;
+			return 0;
+		}
+	}
+
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
+		platform_device_register_simple("rtc-efi", 0, NULL, 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");
+		error = -ENOMEM;
+		goto err_destroy_wq;
+	}
+
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
+				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
+		error = generic_ops_register();
+		if (error)
+			goto err_put;
+		efivar_ssdt_load();
+		platform_device_register_simple("efivars", 0, NULL, 0);
+	}
+
+	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;
+	}
+
+	/* 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;
+	}
+
+	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
+		efi_debugfs_init();
+
+#ifdef CONFIG_EFI_COCO_SECRET
+	if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
+		platform_device_register_simple("efi_secret", 0, NULL, 0);
+#endif
+
+	return 0;
+
+err_remove_group:
+	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
+err_unregister:
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
+				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
+		generic_ops_unregister();
+err_put:
+	kobject_put(efi_kobj);
+	efi_kobj = NULL;
+err_destroy_wq:
+	if (efi_rts_wq)
+		destroy_workqueue(efi_rts_wq);
+
+	return error;
+}
+
+subsys_initcall(efisubsys_init);
+
+void __init efi_find_mirror(void)
+{
+	efi_memory_desc_t *md;
+	u64 mirror_size = 0, total_size = 0;
+
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
+
+	for_each_efi_memory_desc(md) {
+		unsigned long long start = md->phys_addr;
+		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+
+		total_size += size;
+		if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
+			memblock_mark_mirror(start, size);
+			mirror_size += size;
+		}
+	}
+	if (mirror_size)
+		pr_info("Memory: %lldM/%lldM mirrored memory\n",
+			mirror_size>>20, total_size>>20);
+}
+
+/*
+ * 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;
+
+		/* skip bogus entries (including empty ones) */
+		if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
+		    (md->num_pages <= 0) ||
+		    (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
+			continue;
+
+		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;
+}
+
+extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
+	__weak __alias(__efi_mem_desc_lookup);
+
+/*
+ * 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)
+{
+	/* efi_mem_reserve() does not work under Xen */
+	if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
+		return;
+
+	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 const efi_config_table_type_t common_tables[] __initconst = {
+	{ACPI_20_TABLE_GUID,			&efi.acpi20,		"ACPI 2.0"	},
+	{ACPI_TABLE_GUID,			&efi.acpi,		"ACPI"		},
+	{SMBIOS_TABLE_GUID,			&efi.smbios,		"SMBIOS"	},
+	{SMBIOS3_TABLE_GUID,			&efi.smbios3,		"SMBIOS 3.0"	},
+	{EFI_SYSTEM_RESOURCE_TABLE_GUID,	&efi.esrt,		"ESRT"		},
+	{EFI_MEMORY_ATTRIBUTES_TABLE_GUID,	&efi_mem_attr_table,	"MEMATTR"	},
+	{LINUX_EFI_RANDOM_SEED_TABLE_GUID,	&efi_rng_seed,		"RNG"		},
+	{LINUX_EFI_TPM_EVENT_LOG_GUID,		&efi.tpm_log,		"TPMEventLog"	},
+	{LINUX_EFI_TPM_FINAL_LOG_GUID,		&efi.tpm_final_log,	"TPMFinalLog"	},
+	{LINUX_EFI_MEMRESERVE_TABLE_GUID,	&mem_reserve,		"MEMRESERVE"	},
+	{LINUX_EFI_INITRD_MEDIA_GUID,		&initrd,		"INITRD"	},
+	{EFI_RT_PROPERTIES_TABLE_GUID,		&rt_prop,		"RTPROP"	},
+#ifdef CONFIG_EFI_RCI2_TABLE
+	{DELLEMC_EFI_RCI2_TABLE_GUID,		&rci2_table_phys			},
+#endif
+#ifdef CONFIG_LOAD_UEFI_KEYS
+	{LINUX_EFI_MOK_VARIABLE_TABLE_GUID,	&efi.mokvar_table,	"MOKvar"	},
+#endif
+#ifdef CONFIG_EFI_COCO_SECRET
+	{LINUX_EFI_COCO_SECRET_AREA_GUID,	&efi.coco_secret,	"CocoSecret"	},
+#endif
+#ifdef CONFIG_UNACCEPTED_MEMORY
+	{LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID,	&efi.unaccepted,	"Unaccepted"	},
+#endif
+#ifdef CONFIG_EFI_GENERIC_STUB
+	{LINUX_EFI_SCREEN_INFO_TABLE_GUID,	&screen_info_table			},
+#endif
+	{},
+};
+
+static __init int match_config_table(const efi_guid_t *guid,
+				     unsigned long table,
+				     const efi_config_table_type_t *table_types)
+{
+	int i;
+
+	for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
+		if (efi_guidcmp(*guid, table_types[i].guid))
+			continue;
+
+		if (!efi_config_table_is_usable(guid, table)) {
+			if (table_types[i].name[0])
+				pr_cont("(%s=0x%lx unusable) ",
+					table_types[i].name, table);
+			return 1;
+		}
+
+		*(table_types[i].ptr) = table;
+		if (table_types[i].name[0])
+			pr_cont("%s=0x%lx ", table_types[i].name, table);
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * reserve_unaccepted - Map and reserve unaccepted configuration table
+ * @unaccepted: Pointer to unaccepted memory table
+ *
+ * memblock_add() makes sure that the table is mapped in direct mapping. During
+ * normal boot it happens automatically because the table is allocated from
+ * usable memory. But during crashkernel boot only memory specifically reserved
+ * for crash scenario is mapped. memblock_add() forces the table to be mapped
+ * in crashkernel case.
+ *
+ * Align the range to the nearest page borders. Ranges smaller than page size
+ * are not going to be mapped.
+ *
+ * memblock_reserve() makes sure that future allocations will not touch the
+ * table.
+ */
+
+static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
+{
+	phys_addr_t start, size;
+
+	start = PAGE_ALIGN_DOWN(efi.unaccepted);
+	size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size);
+
+	memblock_add(start, size);
+	memblock_reserve(start, size);
+}
+
+int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
+				   int count,
+				   const efi_config_table_type_t *arch_tables)
+{
+	const efi_config_table_64_t *tbl64 = (void *)config_tables;
+	const efi_config_table_32_t *tbl32 = (void *)config_tables;
+	const efi_guid_t *guid;
+	unsigned long table;
+	int i;
+
+	pr_info("");
+	for (i = 0; i < count; i++) {
+		if (!IS_ENABLED(CONFIG_X86)) {
+			guid = &config_tables[i].guid;
+			table = (unsigned long)config_tables[i].table;
+		} else if (efi_enabled(EFI_64BIT)) {
+			guid = &tbl64[i].guid;
+			table = tbl64[i].table;
+
+			if (IS_ENABLED(CONFIG_X86_32) &&
+			    tbl64[i].table > U32_MAX) {
+				pr_cont("\n");
+				pr_err("Table located above 4GB, disabling EFI.\n");
+				return -EINVAL;
+			}
+		} else {
+			guid = &tbl32[i].guid;
+			table = tbl32[i].table;
+		}
+
+		if (!match_config_table(guid, table, common_tables) && arch_tables)
+			match_config_table(guid, table, arch_tables);
+	}
+	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 = min_t(u32, seed->size, SZ_1K); // sanity check
+			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) {
+				add_bootloader_randomness(seed->bits, size);
+				memzero_explicit(seed->bits, size);
+				early_memunmap(seed, sizeof(*seed) + size);
+			} else {
+				pr_err("Could not map UEFI random seed!\n");
+			}
+		}
+	}
+
+	if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
+		efi_memattr_init();
+
+	efi_tpm_eventlog_init();
+
+	if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
+		unsigned long prsv = mem_reserve;
+
+		while (prsv) {
+			struct linux_efi_memreserve *rsv;
+			u8 *p;
+
+			/*
+			 * 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,
+					 struct_size(rsv, entry, 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);
+		}
+	}
+
+	if (rt_prop != EFI_INVALID_TABLE_ADDR) {
+		efi_rt_properties_table_t *tbl;
+
+		tbl = early_memremap(rt_prop, sizeof(*tbl));
+		if (tbl) {
+			efi.runtime_supported_mask &= tbl->runtime_services_supported;
+			early_memunmap(tbl, sizeof(*tbl));
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
+	    initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
+		struct linux_efi_initrd *tbl;
+
+		tbl = early_memremap(initrd, sizeof(*tbl));
+		if (tbl) {
+			phys_initrd_start = tbl->base;
+			phys_initrd_size = tbl->size;
+			early_memunmap(tbl, sizeof(*tbl));
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) &&
+	    efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
+		struct efi_unaccepted_memory *unaccepted;
+
+		unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted));
+		if (unaccepted) {
+
+			if (unaccepted->version == 1) {
+				reserve_unaccepted(unaccepted);
+			} else {
+				efi.unaccepted = EFI_INVALID_TABLE_ADDR;
+			}
+
+			early_memunmap(unaccepted, sizeof(*unaccepted));
+		}
+	}
+
+	return 0;
+}
+
+int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
+{
+	if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
+		pr_err("System table signature incorrect!\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+#ifndef CONFIG_IA64
+static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
+						size_t size)
+{
+	const efi_char16_t *ret;
+
+	ret = early_memremap_ro(fw_vendor, size);
+	if (!ret)
+		pr_err("Could not map the firmware vendor!\n");
+	return ret;
+}
+
+static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
+{
+	early_memunmap((void *)fw_vendor, size);
+}
+#else
+#define map_fw_vendor(p, s)	__va(p)
+#define unmap_fw_vendor(v, s)
+#endif
+
+void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
+				     unsigned long fw_vendor)
+{
+	char vendor[100] = "unknown";
+	const efi_char16_t *c16;
+	size_t i;
+	u16 rev;
+
+	c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
+	if (c16) {
+		for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
+			vendor[i] = c16[i];
+		vendor[i] = '\0';
+
+		unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
+	}
+
+	rev = (u16)systab_hdr->revision;
+	pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);
+
+	rev %= 10;
+	if (rev)
+		pr_cont(".%u", rev);
+
+	pr_cont(" by %s\n", vendor);
+
+	if (IS_ENABLED(CONFIG_X86_64) &&
+	    systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
+	    !strcmp(vendor, "Apple")) {
+		pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
+		efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
+	}
+}
+
+static __initdata char memory_type_name[][13] = {
+	"Reserved",
+	"Loader Code",
+	"Loader Data",
+	"Boot Code",
+	"Boot Data",
+	"Runtime Code",
+	"Runtime Data",
+	"Conventional",
+	"Unusable",
+	"ACPI Reclaim",
+	"ACPI Mem NVS",
+	"MMIO",
+	"MMIO Port",
+	"PAL Code",
+	"Persistent",
+	"Unaccepted",
+};
+
+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_SP | EFI_MEMORY_CPU_CRYPTO |
+		     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|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
+			 attr & EFI_MEMORY_RUNTIME		? "RUN" : "",
+			 attr & EFI_MEMORY_MORE_RELIABLE	? "MR"  : "",
+			 attr & EFI_MEMORY_CPU_CRYPTO   	? "CC"  : "",
+			 attr & EFI_MEMORY_SP			? "SP"  : "",
+			 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, -EINVAL 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;
+}
+EXPORT_SYMBOL_GPL(efi_status_to_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 (mem_reserve == EFI_INVALID_TABLE_ADDR)
+		return -ENODEV;
+
+	efi_memreserve_root = memremap(mem_reserve,
+				       sizeof(*efi_memreserve_root),
+				       MEMREMAP_WB);
+	if (WARN_ON_ONCE(!efi_memreserve_root))
+		return -ENOMEM;
+	return 0;
+}
+
+static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
+{
+	struct resource *res, *parent;
+	int ret;
+
+	res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
+	if (!res)
+		return -ENOMEM;
+
+	res->name	= "reserved";
+	res->flags	= IORESOURCE_MEM;
+	res->start	= addr;
+	res->end	= addr + size - 1;
+
+	/* we expect a conflict with a 'System RAM' region */
+	parent = request_resource_conflict(&iomem_resource, res);
+	ret = parent ? request_resource(parent, res) : 0;
+
+	/*
+	 * Given that efi_mem_reserve_iomem() can be called at any
+	 * time, only call memblock_reserve() if the architecture
+	 * keeps the infrastructure around.
+	 */
+	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
+		memblock_reserve(addr, size);
+
+	return ret;
+}
+
+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; ) {
+		rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
+		if (!rsv)
+			return -ENOMEM;
+		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 efi_mem_reserve_iomem(addr, size);
+		}
+		prsv = rsv->next;
+		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;
+
+	rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
+	if (rc) {
+		free_page((unsigned long)rsv);
+		return rc;
+	}
+
+	/*
+	 * 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 efi_mem_reserve_iomem(addr, size);
+}
+
+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 __init 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