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v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * efi.c - EFI subsystem
   4 *
   5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
   6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
   7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
   8 *
   9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
  10 * allowing the efivarfs to be mounted or the efivars module to be loaded.
  11 * The existance of /sys/firmware/efi may also be used by userspace to
  12 * determine that the system supports EFI.
 
 
  13 */
  14
  15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  16
  17#include <linux/kobject.h>
  18#include <linux/module.h>
  19#include <linux/init.h>
  20#include <linux/debugfs.h>
  21#include <linux/device.h>
  22#include <linux/efi.h>
  23#include <linux/of.h>
 
  24#include <linux/io.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>
  34
  35#include <asm/early_ioremap.h>
  36
  37struct efi __read_mostly efi = {
  38	.runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
  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	.esrt			= EFI_INVALID_TABLE_ADDR,
  44	.tpm_log		= EFI_INVALID_TABLE_ADDR,
  45	.tpm_final_log		= EFI_INVALID_TABLE_ADDR,
  46};
  47EXPORT_SYMBOL(efi);
  48
  49unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
  50static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
  51static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
  52
  53struct mm_struct efi_mm = {
  54	.mm_rb			= RB_ROOT,
  55	.mm_users		= ATOMIC_INIT(2),
  56	.mm_count		= ATOMIC_INIT(1),
  57	MMAP_LOCK_INITIALIZER(efi_mm)
  58	.page_table_lock	= __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
  59	.mmlist			= LIST_HEAD_INIT(efi_mm.mmlist),
  60	.cpu_bitmap		= { [BITS_TO_LONGS(NR_CPUS)] = 0},
  61};
  62
  63struct workqueue_struct *efi_rts_wq;
  64
  65static bool disable_runtime;
  66static int __init setup_noefi(char *arg)
  67{
  68	disable_runtime = true;
  69	return 0;
  70}
  71early_param("noefi", setup_noefi);
  72
  73bool efi_runtime_disabled(void)
  74{
  75	return disable_runtime;
  76}
  77
  78bool __pure __efi_soft_reserve_enabled(void)
  79{
  80	return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
  81}
  82
  83static int __init parse_efi_cmdline(char *str)
  84{
  85	if (!str) {
  86		pr_warn("need at least one option\n");
  87		return -EINVAL;
  88	}
  89
  90	if (parse_option_str(str, "debug"))
  91		set_bit(EFI_DBG, &efi.flags);
  92
  93	if (parse_option_str(str, "noruntime"))
  94		disable_runtime = true;
  95
  96	if (parse_option_str(str, "nosoftreserve"))
  97		set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
  98
  99	return 0;
 100}
 101early_param("efi", parse_efi_cmdline);
 102
 103struct kobject *efi_kobj;
 104
 105/*
 106 * Let's not leave out systab information that snuck into
 107 * the efivars driver
 108 * Note, do not add more fields in systab sysfs file as it breaks sysfs
 109 * one value per file rule!
 110 */
 111static ssize_t systab_show(struct kobject *kobj,
 112			   struct kobj_attribute *attr, char *buf)
 113{
 114	char *str = buf;
 115
 116	if (!kobj || !buf)
 117		return -EINVAL;
 118
 
 
 119	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
 120		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
 121	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
 122		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
 123	/*
 124	 * If both SMBIOS and SMBIOS3 entry points are implemented, the
 125	 * SMBIOS3 entry point shall be preferred, so we list it first to
 126	 * let applications stop parsing after the first match.
 127	 */
 128	if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
 129		str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
 130	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
 131		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
 132
 133	if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
 134		str = efi_systab_show_arch(str);
 
 
 
 135
 136	return str - buf;
 137}
 138
 139static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 140
 141static ssize_t fw_platform_size_show(struct kobject *kobj,
 142				     struct kobj_attribute *attr, char *buf)
 143{
 144	return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
 145}
 146
 147extern __weak struct kobj_attribute efi_attr_fw_vendor;
 148extern __weak struct kobj_attribute efi_attr_runtime;
 149extern __weak struct kobj_attribute efi_attr_config_table;
 150static struct kobj_attribute efi_attr_fw_platform_size =
 151	__ATTR_RO(fw_platform_size);
 152
 153static struct attribute *efi_subsys_attrs[] = {
 154	&efi_attr_systab.attr,
 155	&efi_attr_fw_platform_size.attr,
 156	&efi_attr_fw_vendor.attr,
 157	&efi_attr_runtime.attr,
 158	&efi_attr_config_table.attr,
 
 159	NULL,
 160};
 161
 162umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
 163				   int n)
 164{
 
 
 
 
 
 
 
 
 
 
 
 
 165	return attr->mode;
 166}
 167
 168static const struct attribute_group efi_subsys_attr_group = {
 169	.attrs = efi_subsys_attrs,
 170	.is_visible = efi_attr_is_visible,
 171};
 172
 173static struct efivars generic_efivars;
 174static struct efivar_operations generic_ops;
 175
 176static int generic_ops_register(void)
 177{
 178	generic_ops.get_variable = efi.get_variable;
 
 
 179	generic_ops.get_next_variable = efi.get_next_variable;
 180	generic_ops.query_variable_store = efi_query_variable_store;
 181
 182	if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
 183		generic_ops.set_variable = efi.set_variable;
 184		generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
 185	}
 186	return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
 187}
 188
 189static void generic_ops_unregister(void)
 190{
 191	efivars_unregister(&generic_efivars);
 192}
 193
 194#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
 195#define EFIVAR_SSDT_NAME_MAX	16
 196static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
 197static int __init efivar_ssdt_setup(char *str)
 198{
 199	int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
 200
 201	if (ret)
 202		return ret;
 203
 204	if (strlen(str) < sizeof(efivar_ssdt))
 205		memcpy(efivar_ssdt, str, strlen(str));
 206	else
 207		pr_warn("efivar_ssdt: name too long: %s\n", str);
 208	return 0;
 209}
 210__setup("efivar_ssdt=", efivar_ssdt_setup);
 211
 212static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
 213				   unsigned long name_size, void *data)
 214{
 215	struct efivar_entry *entry;
 216	struct list_head *list = data;
 217	char utf8_name[EFIVAR_SSDT_NAME_MAX];
 218	int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
 219
 220	ucs2_as_utf8(utf8_name, name, limit - 1);
 221	if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
 222		return 0;
 223
 224	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
 225	if (!entry)
 226		return 0;
 227
 228	memcpy(entry->var.VariableName, name, name_size);
 229	memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
 230
 231	efivar_entry_add(entry, list);
 232
 233	return 0;
 234}
 235
 236static __init int efivar_ssdt_load(void)
 237{
 238	LIST_HEAD(entries);
 239	struct efivar_entry *entry, *aux;
 240	unsigned long size;
 241	void *data;
 242	int ret;
 243
 244	if (!efivar_ssdt[0])
 245		return 0;
 246
 247	ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
 248
 249	list_for_each_entry_safe(entry, aux, &entries, list) {
 250		pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
 251			&entry->var.VendorGuid);
 252
 253		list_del(&entry->list);
 254
 255		ret = efivar_entry_size(entry, &size);
 256		if (ret) {
 257			pr_err("failed to get var size\n");
 258			goto free_entry;
 259		}
 260
 261		data = kmalloc(size, GFP_KERNEL);
 262		if (!data) {
 263			ret = -ENOMEM;
 264			goto free_entry;
 265		}
 266
 267		ret = efivar_entry_get(entry, NULL, &size, data);
 268		if (ret) {
 269			pr_err("failed to get var data\n");
 270			goto free_data;
 271		}
 272
 273		ret = acpi_load_table(data, NULL);
 274		if (ret) {
 275			pr_err("failed to load table: %d\n", ret);
 276			goto free_data;
 277		}
 278
 279		goto free_entry;
 280
 281free_data:
 282		kfree(data);
 283
 284free_entry:
 285		kfree(entry);
 286	}
 287
 288	return ret;
 289}
 290#else
 291static inline int efivar_ssdt_load(void) { return 0; }
 292#endif
 293
 294#ifdef CONFIG_DEBUG_FS
 295
 296#define EFI_DEBUGFS_MAX_BLOBS 32
 297
 298static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
 299
 300static void __init efi_debugfs_init(void)
 301{
 302	struct dentry *efi_debugfs;
 303	efi_memory_desc_t *md;
 304	char name[32];
 305	int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
 306	int i = 0;
 307
 308	efi_debugfs = debugfs_create_dir("efi", NULL);
 309	if (IS_ERR_OR_NULL(efi_debugfs))
 310		return;
 311
 312	for_each_efi_memory_desc(md) {
 313		switch (md->type) {
 314		case EFI_BOOT_SERVICES_CODE:
 315			snprintf(name, sizeof(name), "boot_services_code%d",
 316				 type_count[md->type]++);
 317			break;
 318		case EFI_BOOT_SERVICES_DATA:
 319			snprintf(name, sizeof(name), "boot_services_data%d",
 320				 type_count[md->type]++);
 321			break;
 322		default:
 323			continue;
 324		}
 325
 326		if (i >= EFI_DEBUGFS_MAX_BLOBS) {
 327			pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
 328				EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
 329			break;
 330		}
 331
 332		debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
 333		debugfs_blob[i].data = memremap(md->phys_addr,
 334						debugfs_blob[i].size,
 335						MEMREMAP_WB);
 336		if (!debugfs_blob[i].data)
 337			continue;
 338
 339		debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
 340		i++;
 341	}
 342}
 343#else
 344static inline void efi_debugfs_init(void) {}
 345#endif
 346
 347/*
 348 * We register the efi subsystem with the firmware subsystem and the
 349 * efivars subsystem with the efi subsystem, if the system was booted with
 350 * EFI.
 351 */
 352static int __init efisubsys_init(void)
 353{
 354	int error;
 355
 356	if (!efi_enabled(EFI_RUNTIME_SERVICES))
 357		efi.runtime_supported_mask = 0;
 358
 359	if (!efi_enabled(EFI_BOOT))
 360		return 0;
 361
 362	if (efi.runtime_supported_mask) {
 363		/*
 364		 * Since we process only one efi_runtime_service() at a time, an
 365		 * ordered workqueue (which creates only one execution context)
 366		 * should suffice for all our needs.
 367		 */
 368		efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
 369		if (!efi_rts_wq) {
 370			pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
 371			clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 372			efi.runtime_supported_mask = 0;
 373			return 0;
 374		}
 375	}
 376
 377	if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
 378		platform_device_register_simple("rtc-efi", 0, NULL, 0);
 379
 380	/* We register the efi directory at /sys/firmware/efi */
 381	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
 382	if (!efi_kobj) {
 383		pr_err("efi: Firmware registration failed.\n");
 384		destroy_workqueue(efi_rts_wq);
 385		return -ENOMEM;
 386	}
 387
 388	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
 389				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
 390		efivar_ssdt_load();
 391		error = generic_ops_register();
 392		if (error)
 393			goto err_put;
 394		platform_device_register_simple("efivars", 0, NULL, 0);
 395	}
 396
 397	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
 398	if (error) {
 399		pr_err("efi: Sysfs attribute export failed with error %d.\n",
 400		       error);
 401		goto err_unregister;
 402	}
 403
 404	error = efi_runtime_map_init(efi_kobj);
 405	if (error)
 406		goto err_remove_group;
 407
 408	/* and the standard mountpoint for efivarfs */
 409	error = sysfs_create_mount_point(efi_kobj, "efivars");
 410	if (error) {
 411		pr_err("efivars: Subsystem registration failed.\n");
 412		goto err_remove_group;
 413	}
 414
 415	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
 416		efi_debugfs_init();
 417
 418	return 0;
 419
 420err_remove_group:
 421	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
 422err_unregister:
 423	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
 424				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
 425		generic_ops_unregister();
 426err_put:
 427	kobject_put(efi_kobj);
 428	destroy_workqueue(efi_rts_wq);
 429	return error;
 430}
 431
 432subsys_initcall(efisubsys_init);
 433
 434/*
 435 * Find the efi memory descriptor for a given physical address.  Given a
 436 * physical address, determine if it exists within an EFI Memory Map entry,
 437 * and if so, populate the supplied memory descriptor with the appropriate
 438 * data.
 439 */
 440int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
 441{
 442	efi_memory_desc_t *md;
 
 443
 444	if (!efi_enabled(EFI_MEMMAP)) {
 445		pr_err_once("EFI_MEMMAP is not enabled.\n");
 446		return -EINVAL;
 447	}
 448
 
 
 
 
 449	if (!out_md) {
 450		pr_err_once("out_md is null.\n");
 451		return -EINVAL;
 452        }
 
 
 
 
 453
 454	for_each_efi_memory_desc(md) {
 
 
 455		u64 size;
 456		u64 end;
 457
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 458		size = md->num_pages << EFI_PAGE_SHIFT;
 459		end = md->phys_addr + size;
 460		if (phys_addr >= md->phys_addr && phys_addr < end) {
 461			memcpy(out_md, md, sizeof(*out_md));
 
 462			return 0;
 463		}
 
 
 464	}
 
 465	return -ENOENT;
 466}
 467
 468/*
 469 * Calculate the highest address of an efi memory descriptor.
 470 */
 471u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
 472{
 473	u64 size = md->num_pages << EFI_PAGE_SHIFT;
 474	u64 end = md->phys_addr + size;
 475	return end;
 476}
 477
 478void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
 479
 480/**
 481 * efi_mem_reserve - Reserve an EFI memory region
 482 * @addr: Physical address to reserve
 483 * @size: Size of reservation
 484 *
 485 * Mark a region as reserved from general kernel allocation and
 486 * prevent it being released by efi_free_boot_services().
 487 *
 488 * This function should be called drivers once they've parsed EFI
 489 * configuration tables to figure out where their data lives, e.g.
 490 * efi_esrt_init().
 491 */
 492void __init efi_mem_reserve(phys_addr_t addr, u64 size)
 493{
 494	if (!memblock_is_region_reserved(addr, size))
 495		memblock_reserve(addr, size);
 496
 497	/*
 498	 * Some architectures (x86) reserve all boot services ranges
 499	 * until efi_free_boot_services() because of buggy firmware
 500	 * implementations. This means the above memblock_reserve() is
 501	 * superfluous on x86 and instead what it needs to do is
 502	 * ensure the @start, @size is not freed.
 503	 */
 504	efi_arch_mem_reserve(addr, size);
 505}
 506
 507static const efi_config_table_type_t common_tables[] __initconst = {
 508	{ACPI_20_TABLE_GUID,			&efi.acpi20,		"ACPI 2.0"	},
 509	{ACPI_TABLE_GUID,			&efi.acpi,		"ACPI"		},
 510	{SMBIOS_TABLE_GUID,			&efi.smbios,		"SMBIOS"	},
 511	{SMBIOS3_TABLE_GUID,			&efi.smbios3,		"SMBIOS 3.0"	},
 512	{EFI_SYSTEM_RESOURCE_TABLE_GUID,	&efi.esrt,		"ESRT"		},
 513	{EFI_MEMORY_ATTRIBUTES_TABLE_GUID,	&efi_mem_attr_table,	"MEMATTR"	},
 514	{LINUX_EFI_RANDOM_SEED_TABLE_GUID,	&efi_rng_seed,		"RNG"		},
 515	{LINUX_EFI_TPM_EVENT_LOG_GUID,		&efi.tpm_log,		"TPMEventLog"	},
 516	{LINUX_EFI_TPM_FINAL_LOG_GUID,		&efi.tpm_final_log,	"TPMFinalLog"	},
 517	{LINUX_EFI_MEMRESERVE_TABLE_GUID,	&mem_reserve,		"MEMRESERVE"	},
 518	{EFI_RT_PROPERTIES_TABLE_GUID,		&rt_prop,		"RTPROP"	},
 519#ifdef CONFIG_EFI_RCI2_TABLE
 520	{DELLEMC_EFI_RCI2_TABLE_GUID,		&rci2_table_phys			},
 521#endif
 522	{},
 523};
 524
 525static __init int match_config_table(const efi_guid_t *guid,
 526				     unsigned long table,
 527				     const efi_config_table_type_t *table_types)
 528{
 529	int i;
 530
 531	for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
 532		if (!efi_guidcmp(*guid, table_types[i].guid)) {
 533			*(table_types[i].ptr) = table;
 534			if (table_types[i].name[0])
 535				pr_cont("%s=0x%lx ",
 536					table_types[i].name, table);
 537			return 1;
 
 538		}
 539	}
 540
 541	return 0;
 542}
 543
 544int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
 545				   int count,
 546				   const efi_config_table_type_t *arch_tables)
 547{
 548	const efi_config_table_64_t *tbl64 = (void *)config_tables;
 549	const efi_config_table_32_t *tbl32 = (void *)config_tables;
 550	const efi_guid_t *guid;
 551	unsigned long table;
 552	int i;
 553
 
 554	pr_info("");
 555	for (i = 0; i < count; i++) {
 556		if (!IS_ENABLED(CONFIG_X86)) {
 557			guid = &config_tables[i].guid;
 558			table = (unsigned long)config_tables[i].table;
 559		} else if (efi_enabled(EFI_64BIT)) {
 560			guid = &tbl64[i].guid;
 561			table = tbl64[i].table;
 562
 563			if (IS_ENABLED(CONFIG_X86_32) &&
 564			    tbl64[i].table > U32_MAX) {
 
 
 
 
 
 565				pr_cont("\n");
 566				pr_err("Table located above 4GB, disabling EFI.\n");
 567				return -EINVAL;
 568			}
 
 569		} else {
 570			guid = &tbl32[i].guid;
 571			table = tbl32[i].table;
 572		}
 573
 574		if (!match_config_table(guid, table, common_tables) && arch_tables)
 575			match_config_table(guid, table, arch_tables);
 
 
 576	}
 577	pr_cont("\n");
 578	set_bit(EFI_CONFIG_TABLES, &efi.flags);
 579
 580	if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
 581		struct linux_efi_random_seed *seed;
 582		u32 size = 0;
 583
 584		seed = early_memremap(efi_rng_seed, sizeof(*seed));
 585		if (seed != NULL) {
 586			size = READ_ONCE(seed->size);
 587			early_memunmap(seed, sizeof(*seed));
 588		} else {
 589			pr_err("Could not map UEFI random seed!\n");
 590		}
 591		if (size > 0) {
 592			seed = early_memremap(efi_rng_seed,
 593					      sizeof(*seed) + size);
 594			if (seed != NULL) {
 595				pr_notice("seeding entropy pool\n");
 596				add_bootloader_randomness(seed->bits, size);
 597				early_memunmap(seed, sizeof(*seed) + size);
 598			} else {
 599				pr_err("Could not map UEFI random seed!\n");
 600			}
 601		}
 602	}
 603
 604	if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
 605		efi_memattr_init();
 
 
 
 606
 607	efi_tpm_eventlog_init();
 
 
 608
 609	if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
 610		unsigned long prsv = mem_reserve;
 611
 612		while (prsv) {
 613			struct linux_efi_memreserve *rsv;
 614			u8 *p;
 615
 616			/*
 617			 * Just map a full page: that is what we will get
 618			 * anyway, and it permits us to map the entire entry
 619			 * before knowing its size.
 620			 */
 621			p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
 622					   PAGE_SIZE);
 623			if (p == NULL) {
 624				pr_err("Could not map UEFI memreserve entry!\n");
 625				return -ENOMEM;
 626			}
 627
 628			rsv = (void *)(p + prsv % PAGE_SIZE);
 
 
 
 629
 630			/* reserve the entry itself */
 631			memblock_reserve(prsv,
 632					 struct_size(rsv, entry, rsv->size));
 633
 634			for (i = 0; i < atomic_read(&rsv->count); i++) {
 635				memblock_reserve(rsv->entry[i].base,
 636						 rsv->entry[i].size);
 637			}
 638
 639			prsv = rsv->next;
 640			early_memunmap(p, PAGE_SIZE);
 641		}
 
 
 
 
 
 642	}
 643
 644	if (rt_prop != EFI_INVALID_TABLE_ADDR) {
 645		efi_rt_properties_table_t *tbl;
 646
 647		tbl = early_memremap(rt_prop, sizeof(*tbl));
 648		if (tbl) {
 649			efi.runtime_supported_mask &= tbl->runtime_services_supported;
 650			early_memunmap(tbl, sizeof(*tbl));
 651		}
 652	}
 653
 654	return 0;
 655}
 656
 657int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr,
 658				   int min_major_version)
 659{
 660	if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 661		pr_err("System table signature incorrect!\n");
 662		return -EINVAL;
 663	}
 664
 665	if ((systab_hdr->revision >> 16) < min_major_version)
 666		pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n",
 667		       systab_hdr->revision >> 16,
 668		       systab_hdr->revision & 0xffff,
 669		       min_major_version);
 670
 671	return 0;
 
 672}
 
 
 673
 674#ifndef CONFIG_IA64
 675static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
 676						size_t size)
 677{
 678	const efi_char16_t *ret;
 679
 680	ret = early_memremap_ro(fw_vendor, size);
 681	if (!ret)
 682		pr_err("Could not map the firmware vendor!\n");
 683	return ret;
 684}
 
 
 
 
 
 
 
 
 
 
 
 685
 686static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
 
 
 
 
 
 
 687{
 688	early_memunmap((void *)fw_vendor, size);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 689}
 690#else
 691#define map_fw_vendor(p, s)	__va(p)
 692#define unmap_fw_vendor(v, s)
 693#endif
 694
 695void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
 696				     unsigned long fw_vendor)
 697{
 698	char vendor[100] = "unknown";
 699	const efi_char16_t *c16;
 700	size_t i;
 701
 702	c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
 703	if (c16) {
 704		for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
 705			vendor[i] = c16[i];
 706		vendor[i] = '\0';
 707
 708		unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
 709	}
 710
 711	pr_info("EFI v%u.%.02u by %s\n",
 712		systab_hdr->revision >> 16,
 713		systab_hdr->revision & 0xffff,
 714		vendor);
 715}
 
 716
 717static __initdata char memory_type_name[][20] = {
 718	"Reserved",
 719	"Loader Code",
 720	"Loader Data",
 721	"Boot Code",
 722	"Boot Data",
 723	"Runtime Code",
 724	"Runtime Data",
 725	"Conventional Memory",
 726	"Unusable Memory",
 727	"ACPI Reclaim Memory",
 728	"ACPI Memory NVS",
 729	"Memory Mapped I/O",
 730	"MMIO Port Space",
 731	"PAL Code",
 732	"Persistent Memory",
 733};
 734
 735char * __init efi_md_typeattr_format(char *buf, size_t size,
 736				     const efi_memory_desc_t *md)
 737{
 738	char *pos;
 739	int type_len;
 740	u64 attr;
 741
 742	pos = buf;
 743	if (md->type >= ARRAY_SIZE(memory_type_name))
 744		type_len = snprintf(pos, size, "[type=%u", md->type);
 745	else
 746		type_len = snprintf(pos, size, "[%-*s",
 747				    (int)(sizeof(memory_type_name[0]) - 1),
 748				    memory_type_name[md->type]);
 749	if (type_len >= size)
 750		return buf;
 751
 752	pos += type_len;
 753	size -= type_len;
 754
 755	attr = md->attribute;
 756	if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
 757		     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
 758		     EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
 759		     EFI_MEMORY_NV | EFI_MEMORY_SP |
 760		     EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
 761		snprintf(pos, size, "|attr=0x%016llx]",
 762			 (unsigned long long)attr);
 763	else
 764		snprintf(pos, size,
 765			 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
 766			 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
 767			 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
 768			 attr & EFI_MEMORY_SP      ? "SP"  : "",
 769			 attr & EFI_MEMORY_NV      ? "NV"  : "",
 770			 attr & EFI_MEMORY_XP      ? "XP"  : "",
 771			 attr & EFI_MEMORY_RP      ? "RP"  : "",
 772			 attr & EFI_MEMORY_WP      ? "WP"  : "",
 773			 attr & EFI_MEMORY_RO      ? "RO"  : "",
 774			 attr & EFI_MEMORY_UCE     ? "UCE" : "",
 775			 attr & EFI_MEMORY_WB      ? "WB"  : "",
 776			 attr & EFI_MEMORY_WT      ? "WT"  : "",
 777			 attr & EFI_MEMORY_WC      ? "WC"  : "",
 778			 attr & EFI_MEMORY_UC      ? "UC"  : "");
 779	return buf;
 780}
 781
 782/*
 783 * IA64 has a funky EFI memory map that doesn't work the same way as
 784 * other architectures.
 785 */
 786#ifndef CONFIG_IA64
 787/*
 788 * efi_mem_attributes - lookup memmap attributes for physical address
 789 * @phys_addr: the physical address to lookup
 790 *
 791 * Search in the EFI memory map for the region covering
 792 * @phys_addr. Returns the EFI memory attributes if the region
 793 * was found in the memory map, 0 otherwise.
 
 
 
 
 
 794 */
 795u64 efi_mem_attributes(unsigned long phys_addr)
 796{
 
 797	efi_memory_desc_t *md;
 
 798
 799	if (!efi_enabled(EFI_MEMMAP))
 800		return 0;
 801
 802	for_each_efi_memory_desc(md) {
 
 
 803		if ((md->phys_addr <= phys_addr) &&
 804		    (phys_addr < (md->phys_addr +
 805		    (md->num_pages << EFI_PAGE_SHIFT))))
 806			return md->attribute;
 807	}
 808	return 0;
 809}
 810
 811/*
 812 * efi_mem_type - lookup memmap type for physical address
 813 * @phys_addr: the physical address to lookup
 814 *
 815 * Search in the EFI memory map for the region covering @phys_addr.
 816 * Returns the EFI memory type if the region was found in the memory
 817 * map, -EINVAL otherwise.
 818 */
 819int efi_mem_type(unsigned long phys_addr)
 820{
 821	const efi_memory_desc_t *md;
 822
 823	if (!efi_enabled(EFI_MEMMAP))
 824		return -ENOTSUPP;
 825
 826	for_each_efi_memory_desc(md) {
 827		if ((md->phys_addr <= phys_addr) &&
 828		    (phys_addr < (md->phys_addr +
 829				  (md->num_pages << EFI_PAGE_SHIFT))))
 830			return md->type;
 831	}
 832	return -EINVAL;
 833}
 834#endif
 835
 836int efi_status_to_err(efi_status_t status)
 837{
 838	int err;
 839
 840	switch (status) {
 841	case EFI_SUCCESS:
 842		err = 0;
 843		break;
 844	case EFI_INVALID_PARAMETER:
 845		err = -EINVAL;
 846		break;
 847	case EFI_OUT_OF_RESOURCES:
 848		err = -ENOSPC;
 849		break;
 850	case EFI_DEVICE_ERROR:
 851		err = -EIO;
 852		break;
 853	case EFI_WRITE_PROTECTED:
 854		err = -EROFS;
 855		break;
 856	case EFI_SECURITY_VIOLATION:
 857		err = -EACCES;
 858		break;
 859	case EFI_NOT_FOUND:
 860		err = -ENOENT;
 861		break;
 862	case EFI_ABORTED:
 863		err = -EINTR;
 864		break;
 865	default:
 866		err = -EINVAL;
 867	}
 868
 869	return err;
 870}
 871
 872static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
 873static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
 874
 875static int __init efi_memreserve_map_root(void)
 876{
 877	if (mem_reserve == EFI_INVALID_TABLE_ADDR)
 878		return -ENODEV;
 879
 880	efi_memreserve_root = memremap(mem_reserve,
 881				       sizeof(*efi_memreserve_root),
 882				       MEMREMAP_WB);
 883	if (WARN_ON_ONCE(!efi_memreserve_root))
 884		return -ENOMEM;
 885	return 0;
 886}
 887
 888static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
 889{
 890	struct resource *res, *parent;
 891
 892	res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
 893	if (!res)
 894		return -ENOMEM;
 895
 896	res->name	= "reserved";
 897	res->flags	= IORESOURCE_MEM;
 898	res->start	= addr;
 899	res->end	= addr + size - 1;
 900
 901	/* we expect a conflict with a 'System RAM' region */
 902	parent = request_resource_conflict(&iomem_resource, res);
 903	return parent ? request_resource(parent, res) : 0;
 904}
 905
 906int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
 907{
 908	struct linux_efi_memreserve *rsv;
 909	unsigned long prsv;
 910	int rc, index;
 911
 912	if (efi_memreserve_root == (void *)ULONG_MAX)
 913		return -ENODEV;
 914
 915	if (!efi_memreserve_root) {
 916		rc = efi_memreserve_map_root();
 917		if (rc)
 918			return rc;
 919	}
 920
 921	/* first try to find a slot in an existing linked list entry */
 922	for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) {
 923		rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
 924		index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
 925		if (index < rsv->size) {
 926			rsv->entry[index].base = addr;
 927			rsv->entry[index].size = size;
 928
 929			memunmap(rsv);
 930			return efi_mem_reserve_iomem(addr, size);
 931		}
 932		memunmap(rsv);
 933	}
 934
 935	/* no slot found - allocate a new linked list entry */
 936	rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
 937	if (!rsv)
 938		return -ENOMEM;
 939
 940	rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
 941	if (rc) {
 942		free_page((unsigned long)rsv);
 943		return rc;
 944	}
 945
 946	/*
 947	 * The memremap() call above assumes that a linux_efi_memreserve entry
 948	 * never crosses a page boundary, so let's ensure that this remains true
 949	 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
 950	 * using SZ_4K explicitly in the size calculation below.
 951	 */
 952	rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
 953	atomic_set(&rsv->count, 1);
 954	rsv->entry[0].base = addr;
 955	rsv->entry[0].size = size;
 956
 957	spin_lock(&efi_mem_reserve_persistent_lock);
 958	rsv->next = efi_memreserve_root->next;
 959	efi_memreserve_root->next = __pa(rsv);
 960	spin_unlock(&efi_mem_reserve_persistent_lock);
 961
 962	return efi_mem_reserve_iomem(addr, size);
 963}
 964
 965static int __init efi_memreserve_root_init(void)
 966{
 967	if (efi_memreserve_root)
 968		return 0;
 969	if (efi_memreserve_map_root())
 970		efi_memreserve_root = (void *)ULONG_MAX;
 971	return 0;
 972}
 973early_initcall(efi_memreserve_root_init);
 974
 975#ifdef CONFIG_KEXEC
 976static int update_efi_random_seed(struct notifier_block *nb,
 977				  unsigned long code, void *unused)
 978{
 979	struct linux_efi_random_seed *seed;
 980	u32 size = 0;
 981
 982	if (!kexec_in_progress)
 983		return NOTIFY_DONE;
 984
 985	seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
 986	if (seed != NULL) {
 987		size = min(seed->size, EFI_RANDOM_SEED_SIZE);
 988		memunmap(seed);
 989	} else {
 990		pr_err("Could not map UEFI random seed!\n");
 991	}
 992	if (size > 0) {
 993		seed = memremap(efi_rng_seed, sizeof(*seed) + size,
 994				MEMREMAP_WB);
 995		if (seed != NULL) {
 996			seed->size = size;
 997			get_random_bytes(seed->bits, seed->size);
 998			memunmap(seed);
 999		} else {
1000			pr_err("Could not map UEFI random seed!\n");
1001		}
1002	}
1003	return NOTIFY_DONE;
1004}
1005
1006static struct notifier_block efi_random_seed_nb = {
1007	.notifier_call = update_efi_random_seed,
1008};
1009
1010static int __init register_update_efi_random_seed(void)
1011{
1012	if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1013		return 0;
1014	return register_reboot_notifier(&efi_random_seed_nb);
1015}
1016late_initcall(register_update_efi_random_seed);
1017#endif
v4.6
 
  1/*
  2 * efi.c - EFI subsystem
  3 *
  4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
  5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
  6 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
  7 *
  8 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
  9 * allowing the efivarfs to be mounted or the efivars module to be loaded.
 10 * The existance of /sys/firmware/efi may also be used by userspace to
 11 * determine that the system supports EFI.
 12 *
 13 * This file is released under the GPLv2.
 14 */
 15
 16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 17
 18#include <linux/kobject.h>
 19#include <linux/module.h>
 20#include <linux/init.h>
 
 21#include <linux/device.h>
 22#include <linux/efi.h>
 23#include <linux/of.h>
 24#include <linux/of_fdt.h>
 25#include <linux/io.h>
 
 26#include <linux/platform_device.h>
 
 
 
 
 
 
 
 27
 28#include <asm/early_ioremap.h>
 29
 30struct efi __read_mostly efi = {
 31	.mps			= EFI_INVALID_TABLE_ADDR,
 32	.acpi			= EFI_INVALID_TABLE_ADDR,
 33	.acpi20			= EFI_INVALID_TABLE_ADDR,
 34	.smbios			= EFI_INVALID_TABLE_ADDR,
 35	.smbios3		= EFI_INVALID_TABLE_ADDR,
 36	.sal_systab		= EFI_INVALID_TABLE_ADDR,
 37	.boot_info		= EFI_INVALID_TABLE_ADDR,
 38	.hcdp			= EFI_INVALID_TABLE_ADDR,
 39	.uga			= EFI_INVALID_TABLE_ADDR,
 40	.uv_systab		= EFI_INVALID_TABLE_ADDR,
 41	.fw_vendor		= EFI_INVALID_TABLE_ADDR,
 42	.runtime		= EFI_INVALID_TABLE_ADDR,
 43	.config_table		= EFI_INVALID_TABLE_ADDR,
 44	.esrt			= EFI_INVALID_TABLE_ADDR,
 45	.properties_table	= EFI_INVALID_TABLE_ADDR,
 
 46};
 47EXPORT_SYMBOL(efi);
 48
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 49static bool disable_runtime;
 50static int __init setup_noefi(char *arg)
 51{
 52	disable_runtime = true;
 53	return 0;
 54}
 55early_param("noefi", setup_noefi);
 56
 57bool efi_runtime_disabled(void)
 58{
 59	return disable_runtime;
 60}
 61
 
 
 
 
 
 62static int __init parse_efi_cmdline(char *str)
 63{
 64	if (!str) {
 65		pr_warn("need at least one option\n");
 66		return -EINVAL;
 67	}
 68
 69	if (parse_option_str(str, "debug"))
 70		set_bit(EFI_DBG, &efi.flags);
 71
 72	if (parse_option_str(str, "noruntime"))
 73		disable_runtime = true;
 74
 
 
 
 75	return 0;
 76}
 77early_param("efi", parse_efi_cmdline);
 78
 79struct kobject *efi_kobj;
 80
 81/*
 82 * Let's not leave out systab information that snuck into
 83 * the efivars driver
 
 
 84 */
 85static ssize_t systab_show(struct kobject *kobj,
 86			   struct kobj_attribute *attr, char *buf)
 87{
 88	char *str = buf;
 89
 90	if (!kobj || !buf)
 91		return -EINVAL;
 92
 93	if (efi.mps != EFI_INVALID_TABLE_ADDR)
 94		str += sprintf(str, "MPS=0x%lx\n", efi.mps);
 95	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
 96		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
 97	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
 98		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
 99	/*
100	 * If both SMBIOS and SMBIOS3 entry points are implemented, the
101	 * SMBIOS3 entry point shall be preferred, so we list it first to
102	 * let applications stop parsing after the first match.
103	 */
104	if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
105		str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
106	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
107		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
108	if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
109		str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
110	if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
111		str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
112	if (efi.uga != EFI_INVALID_TABLE_ADDR)
113		str += sprintf(str, "UGA=0x%lx\n", efi.uga);
114
115	return str - buf;
116}
117
118static struct kobj_attribute efi_attr_systab =
119			__ATTR(systab, 0400, systab_show, NULL);
120
121#define EFI_FIELD(var) efi.var
122
123#define EFI_ATTR_SHOW(name) \
124static ssize_t name##_show(struct kobject *kobj, \
125				struct kobj_attribute *attr, char *buf) \
126{ \
127	return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
128}
129
130EFI_ATTR_SHOW(fw_vendor);
131EFI_ATTR_SHOW(runtime);
132EFI_ATTR_SHOW(config_table);
133
134static ssize_t fw_platform_size_show(struct kobject *kobj,
135				     struct kobj_attribute *attr, char *buf)
136{
137	return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
138}
139
140static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
141static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
142static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
143static struct kobj_attribute efi_attr_fw_platform_size =
144	__ATTR_RO(fw_platform_size);
145
146static struct attribute *efi_subsys_attrs[] = {
147	&efi_attr_systab.attr,
 
148	&efi_attr_fw_vendor.attr,
149	&efi_attr_runtime.attr,
150	&efi_attr_config_table.attr,
151	&efi_attr_fw_platform_size.attr,
152	NULL,
153};
154
155static umode_t efi_attr_is_visible(struct kobject *kobj,
156				   struct attribute *attr, int n)
157{
158	if (attr == &efi_attr_fw_vendor.attr) {
159		if (efi_enabled(EFI_PARAVIRT) ||
160				efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
161			return 0;
162	} else if (attr == &efi_attr_runtime.attr) {
163		if (efi.runtime == EFI_INVALID_TABLE_ADDR)
164			return 0;
165	} else if (attr == &efi_attr_config_table.attr) {
166		if (efi.config_table == EFI_INVALID_TABLE_ADDR)
167			return 0;
168	}
169
170	return attr->mode;
171}
172
173static struct attribute_group efi_subsys_attr_group = {
174	.attrs = efi_subsys_attrs,
175	.is_visible = efi_attr_is_visible,
176};
177
178static struct efivars generic_efivars;
179static struct efivar_operations generic_ops;
180
181static int generic_ops_register(void)
182{
183	generic_ops.get_variable = efi.get_variable;
184	generic_ops.set_variable = efi.set_variable;
185	generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
186	generic_ops.get_next_variable = efi.get_next_variable;
187	generic_ops.query_variable_store = efi_query_variable_store;
188
 
 
 
 
189	return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
190}
191
192static void generic_ops_unregister(void)
193{
194	efivars_unregister(&generic_efivars);
195}
196
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
197/*
198 * We register the efi subsystem with the firmware subsystem and the
199 * efivars subsystem with the efi subsystem, if the system was booted with
200 * EFI.
201 */
202static int __init efisubsys_init(void)
203{
204	int error;
205
 
 
 
206	if (!efi_enabled(EFI_BOOT))
207		return 0;
208
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
209	/* We register the efi directory at /sys/firmware/efi */
210	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
211	if (!efi_kobj) {
212		pr_err("efi: Firmware registration failed.\n");
 
213		return -ENOMEM;
214	}
215
216	error = generic_ops_register();
217	if (error)
218		goto err_put;
 
 
 
 
 
219
220	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
221	if (error) {
222		pr_err("efi: Sysfs attribute export failed with error %d.\n",
223		       error);
224		goto err_unregister;
225	}
226
227	error = efi_runtime_map_init(efi_kobj);
228	if (error)
229		goto err_remove_group;
230
231	/* and the standard mountpoint for efivarfs */
232	error = sysfs_create_mount_point(efi_kobj, "efivars");
233	if (error) {
234		pr_err("efivars: Subsystem registration failed.\n");
235		goto err_remove_group;
236	}
237
 
 
 
238	return 0;
239
240err_remove_group:
241	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
242err_unregister:
243	generic_ops_unregister();
 
 
244err_put:
245	kobject_put(efi_kobj);
 
246	return error;
247}
248
249subsys_initcall(efisubsys_init);
250
251/*
252 * Find the efi memory descriptor for a given physical address.  Given a
253 * physicall address, determine if it exists within an EFI Memory Map entry,
254 * and if so, populate the supplied memory descriptor with the appropriate
255 * data.
256 */
257int __init efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
258{
259	struct efi_memory_map *map = efi.memmap;
260	phys_addr_t p, e;
261
262	if (!efi_enabled(EFI_MEMMAP)) {
263		pr_err_once("EFI_MEMMAP is not enabled.\n");
264		return -EINVAL;
265	}
266
267	if (!map) {
268		pr_err_once("efi.memmap is not set.\n");
269		return -EINVAL;
270	}
271	if (!out_md) {
272		pr_err_once("out_md is null.\n");
273		return -EINVAL;
274        }
275	if (WARN_ON_ONCE(!map->phys_map))
276		return -EINVAL;
277	if (WARN_ON_ONCE(map->nr_map == 0) || WARN_ON_ONCE(map->desc_size == 0))
278		return -EINVAL;
279
280	e = map->phys_map + map->nr_map * map->desc_size;
281	for (p = map->phys_map; p < e; p += map->desc_size) {
282		efi_memory_desc_t *md;
283		u64 size;
284		u64 end;
285
286		/*
287		 * If a driver calls this after efi_free_boot_services,
288		 * ->map will be NULL, and the target may also not be mapped.
289		 * So just always get our own virtual map on the CPU.
290		 *
291		 */
292		md = early_memremap(p, sizeof (*md));
293		if (!md) {
294			pr_err_once("early_memremap(%pa, %zu) failed.\n",
295				    &p, sizeof (*md));
296			return -ENOMEM;
297		}
298
299		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
300		    md->type != EFI_BOOT_SERVICES_DATA &&
301		    md->type != EFI_RUNTIME_SERVICES_DATA) {
302			early_memunmap(md, sizeof (*md));
303			continue;
304		}
305
306		size = md->num_pages << EFI_PAGE_SHIFT;
307		end = md->phys_addr + size;
308		if (phys_addr >= md->phys_addr && phys_addr < end) {
309			memcpy(out_md, md, sizeof(*out_md));
310			early_memunmap(md, sizeof (*md));
311			return 0;
312		}
313
314		early_memunmap(md, sizeof (*md));
315	}
316	pr_err_once("requested map not found.\n");
317	return -ENOENT;
318}
319
320/*
321 * Calculate the highest address of an efi memory descriptor.
322 */
323u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
324{
325	u64 size = md->num_pages << EFI_PAGE_SHIFT;
326	u64 end = md->phys_addr + size;
327	return end;
328}
329
330static __initdata efi_config_table_type_t common_tables[] = {
331	{ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
332	{ACPI_TABLE_GUID, "ACPI", &efi.acpi},
333	{HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
334	{MPS_TABLE_GUID, "MPS", &efi.mps},
335	{SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
336	{SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
337	{SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
338	{UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
339	{EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
340	{EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
341	{NULL_GUID, NULL, NULL},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
342};
343
344static __init int match_config_table(efi_guid_t *guid,
345				     unsigned long table,
346				     efi_config_table_type_t *table_types)
347{
348	int i;
349
350	if (table_types) {
351		for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
352			if (!efi_guidcmp(*guid, table_types[i].guid)) {
353				*(table_types[i].ptr) = table;
354				pr_cont(" %s=0x%lx ",
355					table_types[i].name, table);
356				return 1;
357			}
358		}
359	}
360
361	return 0;
362}
363
364int __init efi_config_parse_tables(void *config_tables, int count, int sz,
365				   efi_config_table_type_t *arch_tables)
366{
367	void *tablep;
 
 
 
 
368	int i;
369
370	tablep = config_tables;
371	pr_info("");
372	for (i = 0; i < count; i++) {
373		efi_guid_t guid;
374		unsigned long table;
 
 
 
 
375
376		if (efi_enabled(EFI_64BIT)) {
377			u64 table64;
378			guid = ((efi_config_table_64_t *)tablep)->guid;
379			table64 = ((efi_config_table_64_t *)tablep)->table;
380			table = table64;
381#ifndef CONFIG_64BIT
382			if (table64 >> 32) {
383				pr_cont("\n");
384				pr_err("Table located above 4GB, disabling EFI.\n");
385				return -EINVAL;
386			}
387#endif
388		} else {
389			guid = ((efi_config_table_32_t *)tablep)->guid;
390			table = ((efi_config_table_32_t *)tablep)->table;
391		}
392
393		if (!match_config_table(&guid, table, common_tables))
394			match_config_table(&guid, table, arch_tables);
395
396		tablep += sz;
397	}
398	pr_cont("\n");
399	set_bit(EFI_CONFIG_TABLES, &efi.flags);
400
401	/* Parse the EFI Properties table if it exists */
402	if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
403		efi_properties_table_t *tbl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
404
405		tbl = early_memremap(efi.properties_table, sizeof(*tbl));
406		if (tbl == NULL) {
407			pr_err("Could not map Properties table!\n");
408			return -ENOMEM;
409		}
410
411		if (tbl->memory_protection_attribute &
412		    EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
413			set_bit(EFI_NX_PE_DATA, &efi.flags);
414
415		early_memunmap(tbl, sizeof(*tbl));
416	}
417
418	return 0;
419}
 
 
 
 
 
 
 
 
 
 
 
 
 
420
421int __init efi_config_init(efi_config_table_type_t *arch_tables)
422{
423	void *config_tables;
424	int sz, ret;
425
426	if (efi_enabled(EFI_64BIT))
427		sz = sizeof(efi_config_table_64_t);
428	else
429		sz = sizeof(efi_config_table_32_t);
 
 
 
 
430
431	/*
432	 * Let's see what config tables the firmware passed to us.
433	 */
434	config_tables = early_memremap(efi.systab->tables,
435				       efi.systab->nr_tables * sz);
436	if (config_tables == NULL) {
437		pr_err("Could not map Configuration table!\n");
438		return -ENOMEM;
439	}
440
441	ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
442				      arch_tables);
443
444	early_memunmap(config_tables, efi.systab->nr_tables * sz);
445	return ret;
 
 
 
 
 
 
446}
447
448#ifdef CONFIG_EFI_VARS_MODULE
449static int __init efi_load_efivars(void)
450{
451	struct platform_device *pdev;
 
 
 
452
453	if (!efi_enabled(EFI_RUNTIME_SERVICES))
454		return 0;
 
 
 
455
456	pdev = platform_device_register_simple("efivars", 0, NULL, 0);
457	return IS_ERR(pdev) ? PTR_ERR(pdev) : 0;
458}
459device_initcall(efi_load_efivars);
460#endif
461
462#ifdef CONFIG_EFI_PARAMS_FROM_FDT
463
464#define UEFI_PARAM(name, prop, field)			   \
465	{						   \
466		{ name },				   \
467		{ prop },				   \
468		offsetof(struct efi_fdt_params, field),    \
469		FIELD_SIZEOF(struct efi_fdt_params, field) \
470	}
471
472static __initdata struct {
473	const char name[32];
474	const char propname[32];
475	int offset;
476	int size;
477} dt_params[] = {
478	UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
479	UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
480	UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
481	UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
482	UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
483};
484
485struct param_info {
486	int found;
487	void *params;
488};
489
490static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
491				       int depth, void *data)
492{
493	struct param_info *info = data;
494	const void *prop;
495	void *dest;
496	u64 val;
497	int i, len;
498
499	if (depth != 1 || strcmp(uname, "chosen") != 0)
500		return 0;
501
502	for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
503		prop = of_get_flat_dt_prop(node, dt_params[i].propname, &len);
504		if (!prop)
505			return 0;
506		dest = info->params + dt_params[i].offset;
507		info->found++;
508
509		val = of_read_number(prop, len / sizeof(u32));
510
511		if (dt_params[i].size == sizeof(u32))
512			*(u32 *)dest = val;
513		else
514			*(u64 *)dest = val;
515
516		if (efi_enabled(EFI_DBG))
517			pr_info("  %s: 0x%0*llx\n", dt_params[i].name,
518				dt_params[i].size * 2, val);
519	}
520	return 1;
521}
 
 
 
 
522
523int __init efi_get_fdt_params(struct efi_fdt_params *params)
 
524{
525	struct param_info info;
526	int ret;
527
528	pr_info("Getting EFI parameters from FDT:\n");
529
530	info.found = 0;
531	info.params = params;
532
533	ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
534	if (!info.found)
535		pr_info("UEFI not found.\n");
536	else if (!ret)
537		pr_err("Can't find '%s' in device tree!\n",
538		       dt_params[info.found].name);
539
540	return ret;
 
541}
542#endif /* CONFIG_EFI_PARAMS_FROM_FDT */
543
544static __initdata char memory_type_name[][20] = {
545	"Reserved",
546	"Loader Code",
547	"Loader Data",
548	"Boot Code",
549	"Boot Data",
550	"Runtime Code",
551	"Runtime Data",
552	"Conventional Memory",
553	"Unusable Memory",
554	"ACPI Reclaim Memory",
555	"ACPI Memory NVS",
556	"Memory Mapped I/O",
557	"MMIO Port Space",
558	"PAL Code",
559	"Persistent Memory",
560};
561
562char * __init efi_md_typeattr_format(char *buf, size_t size,
563				     const efi_memory_desc_t *md)
564{
565	char *pos;
566	int type_len;
567	u64 attr;
568
569	pos = buf;
570	if (md->type >= ARRAY_SIZE(memory_type_name))
571		type_len = snprintf(pos, size, "[type=%u", md->type);
572	else
573		type_len = snprintf(pos, size, "[%-*s",
574				    (int)(sizeof(memory_type_name[0]) - 1),
575				    memory_type_name[md->type]);
576	if (type_len >= size)
577		return buf;
578
579	pos += type_len;
580	size -= type_len;
581
582	attr = md->attribute;
583	if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
584		     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
585		     EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
586		     EFI_MEMORY_NV |
587		     EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
588		snprintf(pos, size, "|attr=0x%016llx]",
589			 (unsigned long long)attr);
590	else
591		snprintf(pos, size,
592			 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
593			 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
594			 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
 
595			 attr & EFI_MEMORY_NV      ? "NV"  : "",
596			 attr & EFI_MEMORY_XP      ? "XP"  : "",
597			 attr & EFI_MEMORY_RP      ? "RP"  : "",
598			 attr & EFI_MEMORY_WP      ? "WP"  : "",
599			 attr & EFI_MEMORY_RO      ? "RO"  : "",
600			 attr & EFI_MEMORY_UCE     ? "UCE" : "",
601			 attr & EFI_MEMORY_WB      ? "WB"  : "",
602			 attr & EFI_MEMORY_WT      ? "WT"  : "",
603			 attr & EFI_MEMORY_WC      ? "WC"  : "",
604			 attr & EFI_MEMORY_UC      ? "UC"  : "");
605	return buf;
606}
607
608/*
 
 
 
 
 
609 * efi_mem_attributes - lookup memmap attributes for physical address
610 * @phys_addr: the physical address to lookup
611 *
612 * Search in the EFI memory map for the region covering
613 * @phys_addr. Returns the EFI memory attributes if the region
614 * was found in the memory map, 0 otherwise.
615 *
616 * Despite being marked __weak, most architectures should *not*
617 * override this function. It is __weak solely for the benefit
618 * of ia64 which has a funky EFI memory map that doesn't work
619 * the same way as other architectures.
620 */
621u64 __weak efi_mem_attributes(unsigned long phys_addr)
622{
623	struct efi_memory_map *map;
624	efi_memory_desc_t *md;
625	void *p;
626
627	if (!efi_enabled(EFI_MEMMAP))
628		return 0;
629
630	map = efi.memmap;
631	for (p = map->map; p < map->map_end; p += map->desc_size) {
632		md = p;
633		if ((md->phys_addr <= phys_addr) &&
634		    (phys_addr < (md->phys_addr +
635		    (md->num_pages << EFI_PAGE_SHIFT))))
636			return md->attribute;
637	}
638	return 0;
639}