xref: /openbmc/linux/drivers/firmware/efi/efi.c (revision f4356947)
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/initrd.h>
25 #include <linux/io.h>
26 #include <linux/kexec.h>
27 #include <linux/platform_device.h>
28 #include <linux/random.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/acpi.h>
32 #include <linux/ucs2_string.h>
33 #include <linux/memblock.h>
34 #include <linux/security.h>
35 
36 #include <asm/early_ioremap.h>
37 
38 struct efi __read_mostly efi = {
39 	.runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
40 	.acpi			= EFI_INVALID_TABLE_ADDR,
41 	.acpi20			= EFI_INVALID_TABLE_ADDR,
42 	.smbios			= EFI_INVALID_TABLE_ADDR,
43 	.smbios3		= EFI_INVALID_TABLE_ADDR,
44 	.esrt			= EFI_INVALID_TABLE_ADDR,
45 	.tpm_log		= EFI_INVALID_TABLE_ADDR,
46 	.tpm_final_log		= EFI_INVALID_TABLE_ADDR,
47 #ifdef CONFIG_LOAD_UEFI_KEYS
48 	.mokvar_table		= EFI_INVALID_TABLE_ADDR,
49 #endif
50 #ifdef CONFIG_EFI_COCO_SECRET
51 	.coco_secret		= EFI_INVALID_TABLE_ADDR,
52 #endif
53 };
54 EXPORT_SYMBOL(efi);
55 
56 unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
57 static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
58 static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
59 static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
60 
61 extern unsigned long screen_info_table;
62 
63 struct mm_struct efi_mm = {
64 	.mm_mt			= MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
65 	.mm_users		= ATOMIC_INIT(2),
66 	.mm_count		= ATOMIC_INIT(1),
67 	.write_protect_seq      = SEQCNT_ZERO(efi_mm.write_protect_seq),
68 	MMAP_LOCK_INITIALIZER(efi_mm)
69 	.page_table_lock	= __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
70 	.mmlist			= LIST_HEAD_INIT(efi_mm.mmlist),
71 	.cpu_bitmap		= { [BITS_TO_LONGS(NR_CPUS)] = 0},
72 };
73 
74 struct workqueue_struct *efi_rts_wq;
75 
76 static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
77 static int __init setup_noefi(char *arg)
78 {
79 	disable_runtime = true;
80 	return 0;
81 }
82 early_param("noefi", setup_noefi);
83 
84 bool efi_runtime_disabled(void)
85 {
86 	return disable_runtime;
87 }
88 
89 bool __pure __efi_soft_reserve_enabled(void)
90 {
91 	return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
92 }
93 
94 static int __init parse_efi_cmdline(char *str)
95 {
96 	if (!str) {
97 		pr_warn("need at least one option\n");
98 		return -EINVAL;
99 	}
100 
101 	if (parse_option_str(str, "debug"))
102 		set_bit(EFI_DBG, &efi.flags);
103 
104 	if (parse_option_str(str, "noruntime"))
105 		disable_runtime = true;
106 
107 	if (parse_option_str(str, "runtime"))
108 		disable_runtime = false;
109 
110 	if (parse_option_str(str, "nosoftreserve"))
111 		set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
112 
113 	return 0;
114 }
115 early_param("efi", parse_efi_cmdline);
116 
117 struct kobject *efi_kobj;
118 
119 /*
120  * Let's not leave out systab information that snuck into
121  * the efivars driver
122  * Note, do not add more fields in systab sysfs file as it breaks sysfs
123  * one value per file rule!
124  */
125 static ssize_t systab_show(struct kobject *kobj,
126 			   struct kobj_attribute *attr, char *buf)
127 {
128 	char *str = buf;
129 
130 	if (!kobj || !buf)
131 		return -EINVAL;
132 
133 	if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
134 		str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
135 	if (efi.acpi != EFI_INVALID_TABLE_ADDR)
136 		str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
137 	/*
138 	 * If both SMBIOS and SMBIOS3 entry points are implemented, the
139 	 * SMBIOS3 entry point shall be preferred, so we list it first to
140 	 * let applications stop parsing after the first match.
141 	 */
142 	if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
143 		str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
144 	if (efi.smbios != EFI_INVALID_TABLE_ADDR)
145 		str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
146 
147 	if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
148 		str = efi_systab_show_arch(str);
149 
150 	return str - buf;
151 }
152 
153 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
154 
155 static ssize_t fw_platform_size_show(struct kobject *kobj,
156 				     struct kobj_attribute *attr, char *buf)
157 {
158 	return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
159 }
160 
161 extern __weak struct kobj_attribute efi_attr_fw_vendor;
162 extern __weak struct kobj_attribute efi_attr_runtime;
163 extern __weak struct kobj_attribute efi_attr_config_table;
164 static struct kobj_attribute efi_attr_fw_platform_size =
165 	__ATTR_RO(fw_platform_size);
166 
167 static struct attribute *efi_subsys_attrs[] = {
168 	&efi_attr_systab.attr,
169 	&efi_attr_fw_platform_size.attr,
170 	&efi_attr_fw_vendor.attr,
171 	&efi_attr_runtime.attr,
172 	&efi_attr_config_table.attr,
173 	NULL,
174 };
175 
176 umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
177 				   int n)
178 {
179 	return attr->mode;
180 }
181 
182 static const struct attribute_group efi_subsys_attr_group = {
183 	.attrs = efi_subsys_attrs,
184 	.is_visible = efi_attr_is_visible,
185 };
186 
187 static struct efivars generic_efivars;
188 static struct efivar_operations generic_ops;
189 
190 static bool generic_ops_supported(void)
191 {
192 	unsigned long name_size;
193 	efi_status_t status;
194 	efi_char16_t name;
195 	efi_guid_t guid;
196 
197 	name_size = sizeof(name);
198 
199 	status = efi.get_next_variable(&name_size, &name, &guid);
200 	if (status == EFI_UNSUPPORTED)
201 		return false;
202 
203 	return true;
204 }
205 
206 static int generic_ops_register(void)
207 {
208 	if (!generic_ops_supported())
209 		return 0;
210 
211 	generic_ops.get_variable = efi.get_variable;
212 	generic_ops.get_next_variable = efi.get_next_variable;
213 	generic_ops.query_variable_store = efi_query_variable_store;
214 
215 	if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
216 		generic_ops.set_variable = efi.set_variable;
217 		generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
218 	}
219 	return efivars_register(&generic_efivars, &generic_ops);
220 }
221 
222 static void generic_ops_unregister(void)
223 {
224 	if (!generic_ops.get_variable)
225 		return;
226 
227 	efivars_unregister(&generic_efivars);
228 }
229 
230 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
231 #define EFIVAR_SSDT_NAME_MAX	16UL
232 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
233 static int __init efivar_ssdt_setup(char *str)
234 {
235 	int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
236 
237 	if (ret)
238 		return ret;
239 
240 	if (strlen(str) < sizeof(efivar_ssdt))
241 		memcpy(efivar_ssdt, str, strlen(str));
242 	else
243 		pr_warn("efivar_ssdt: name too long: %s\n", str);
244 	return 1;
245 }
246 __setup("efivar_ssdt=", efivar_ssdt_setup);
247 
248 static __init int efivar_ssdt_load(void)
249 {
250 	unsigned long name_size = 256;
251 	efi_char16_t *name = NULL;
252 	efi_status_t status;
253 	efi_guid_t guid;
254 
255 	if (!efivar_ssdt[0])
256 		return 0;
257 
258 	name = kzalloc(name_size, GFP_KERNEL);
259 	if (!name)
260 		return -ENOMEM;
261 
262 	for (;;) {
263 		char utf8_name[EFIVAR_SSDT_NAME_MAX];
264 		unsigned long data_size = 0;
265 		void *data;
266 		int limit;
267 
268 		status = efi.get_next_variable(&name_size, name, &guid);
269 		if (status == EFI_NOT_FOUND) {
270 			break;
271 		} else if (status == EFI_BUFFER_TOO_SMALL) {
272 			name = krealloc(name, name_size, GFP_KERNEL);
273 			if (!name)
274 				return -ENOMEM;
275 			continue;
276 		}
277 
278 		limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
279 		ucs2_as_utf8(utf8_name, name, limit - 1);
280 		if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
281 			continue;
282 
283 		pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
284 
285 		status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
286 		if (status != EFI_BUFFER_TOO_SMALL || !data_size)
287 			return -EIO;
288 
289 		data = kmalloc(data_size, GFP_KERNEL);
290 		if (!data)
291 			return -ENOMEM;
292 
293 		status = efi.get_variable(name, &guid, NULL, &data_size, data);
294 		if (status == EFI_SUCCESS) {
295 			acpi_status ret = acpi_load_table(data, NULL);
296 			if (ret)
297 				pr_err("failed to load table: %u\n", ret);
298 			else
299 				continue;
300 		} else {
301 			pr_err("failed to get var data: 0x%lx\n", status);
302 		}
303 		kfree(data);
304 	}
305 	return 0;
306 }
307 #else
308 static inline int efivar_ssdt_load(void) { return 0; }
309 #endif
310 
311 #ifdef CONFIG_DEBUG_FS
312 
313 #define EFI_DEBUGFS_MAX_BLOBS 32
314 
315 static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
316 
317 static void __init efi_debugfs_init(void)
318 {
319 	struct dentry *efi_debugfs;
320 	efi_memory_desc_t *md;
321 	char name[32];
322 	int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
323 	int i = 0;
324 
325 	efi_debugfs = debugfs_create_dir("efi", NULL);
326 	if (IS_ERR_OR_NULL(efi_debugfs))
327 		return;
328 
329 	for_each_efi_memory_desc(md) {
330 		switch (md->type) {
331 		case EFI_BOOT_SERVICES_CODE:
332 			snprintf(name, sizeof(name), "boot_services_code%d",
333 				 type_count[md->type]++);
334 			break;
335 		case EFI_BOOT_SERVICES_DATA:
336 			snprintf(name, sizeof(name), "boot_services_data%d",
337 				 type_count[md->type]++);
338 			break;
339 		default:
340 			continue;
341 		}
342 
343 		if (i >= EFI_DEBUGFS_MAX_BLOBS) {
344 			pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
345 				EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
346 			break;
347 		}
348 
349 		debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
350 		debugfs_blob[i].data = memremap(md->phys_addr,
351 						debugfs_blob[i].size,
352 						MEMREMAP_WB);
353 		if (!debugfs_blob[i].data)
354 			continue;
355 
356 		debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
357 		i++;
358 	}
359 }
360 #else
361 static inline void efi_debugfs_init(void) {}
362 #endif
363 
364 static void refresh_nv_rng_seed(struct work_struct *work)
365 {
366 	u8 seed[EFI_RANDOM_SEED_SIZE];
367 
368 	get_random_bytes(seed, sizeof(seed));
369 	efi.set_variable(L"RandomSeed", &LINUX_EFI_RANDOM_SEED_TABLE_GUID,
370 			 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS |
371 			 EFI_VARIABLE_RUNTIME_ACCESS, sizeof(seed), seed);
372 	memzero_explicit(seed, sizeof(seed));
373 }
374 static int refresh_nv_rng_seed_notification(struct notifier_block *nb, unsigned long action, void *data)
375 {
376 	static DECLARE_WORK(work, refresh_nv_rng_seed);
377 	schedule_work(&work);
378 	return NOTIFY_DONE;
379 }
380 static struct notifier_block refresh_nv_rng_seed_nb = { .notifier_call = refresh_nv_rng_seed_notification };
381 
382 /*
383  * We register the efi subsystem with the firmware subsystem and the
384  * efivars subsystem with the efi subsystem, if the system was booted with
385  * EFI.
386  */
387 static int __init efisubsys_init(void)
388 {
389 	int error;
390 
391 	if (!efi_enabled(EFI_RUNTIME_SERVICES))
392 		efi.runtime_supported_mask = 0;
393 
394 	if (!efi_enabled(EFI_BOOT))
395 		return 0;
396 
397 	if (efi.runtime_supported_mask) {
398 		/*
399 		 * Since we process only one efi_runtime_service() at a time, an
400 		 * ordered workqueue (which creates only one execution context)
401 		 * should suffice for all our needs.
402 		 */
403 		efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
404 		if (!efi_rts_wq) {
405 			pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
406 			clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
407 			efi.runtime_supported_mask = 0;
408 			return 0;
409 		}
410 	}
411 
412 	if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
413 		platform_device_register_simple("rtc-efi", 0, NULL, 0);
414 
415 	/* We register the efi directory at /sys/firmware/efi */
416 	efi_kobj = kobject_create_and_add("efi", firmware_kobj);
417 	if (!efi_kobj) {
418 		pr_err("efi: Firmware registration failed.\n");
419 		error = -ENOMEM;
420 		goto err_destroy_wq;
421 	}
422 
423 	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
424 				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
425 		error = generic_ops_register();
426 		if (error)
427 			goto err_put;
428 		efivar_ssdt_load();
429 		platform_device_register_simple("efivars", 0, NULL, 0);
430 	}
431 
432 	error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
433 	if (error) {
434 		pr_err("efi: Sysfs attribute export failed with error %d.\n",
435 		       error);
436 		goto err_unregister;
437 	}
438 
439 	/* and the standard mountpoint for efivarfs */
440 	error = sysfs_create_mount_point(efi_kobj, "efivars");
441 	if (error) {
442 		pr_err("efivars: Subsystem registration failed.\n");
443 		goto err_remove_group;
444 	}
445 
446 	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
447 		efi_debugfs_init();
448 
449 #ifdef CONFIG_EFI_COCO_SECRET
450 	if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
451 		platform_device_register_simple("efi_secret", 0, NULL, 0);
452 #endif
453 
454 	if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE))
455 		execute_with_initialized_rng(&refresh_nv_rng_seed_nb);
456 
457 	return 0;
458 
459 err_remove_group:
460 	sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
461 err_unregister:
462 	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
463 				      EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
464 		generic_ops_unregister();
465 err_put:
466 	kobject_put(efi_kobj);
467 	efi_kobj = NULL;
468 err_destroy_wq:
469 	if (efi_rts_wq)
470 		destroy_workqueue(efi_rts_wq);
471 
472 	return error;
473 }
474 
475 subsys_initcall(efisubsys_init);
476 
477 void __init efi_find_mirror(void)
478 {
479 	efi_memory_desc_t *md;
480 	u64 mirror_size = 0, total_size = 0;
481 
482 	if (!efi_enabled(EFI_MEMMAP))
483 		return;
484 
485 	for_each_efi_memory_desc(md) {
486 		unsigned long long start = md->phys_addr;
487 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
488 
489 		total_size += size;
490 		if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
491 			memblock_mark_mirror(start, size);
492 			mirror_size += size;
493 		}
494 	}
495 	if (mirror_size)
496 		pr_info("Memory: %lldM/%lldM mirrored memory\n",
497 			mirror_size>>20, total_size>>20);
498 }
499 
500 /*
501  * Find the efi memory descriptor for a given physical address.  Given a
502  * physical address, determine if it exists within an EFI Memory Map entry,
503  * and if so, populate the supplied memory descriptor with the appropriate
504  * data.
505  */
506 int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
507 {
508 	efi_memory_desc_t *md;
509 
510 	if (!efi_enabled(EFI_MEMMAP)) {
511 		pr_err_once("EFI_MEMMAP is not enabled.\n");
512 		return -EINVAL;
513 	}
514 
515 	if (!out_md) {
516 		pr_err_once("out_md is null.\n");
517 		return -EINVAL;
518         }
519 
520 	for_each_efi_memory_desc(md) {
521 		u64 size;
522 		u64 end;
523 
524 		/* skip bogus entries (including empty ones) */
525 		if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
526 		    (md->num_pages <= 0) ||
527 		    (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
528 			continue;
529 
530 		size = md->num_pages << EFI_PAGE_SHIFT;
531 		end = md->phys_addr + size;
532 		if (phys_addr >= md->phys_addr && phys_addr < end) {
533 			memcpy(out_md, md, sizeof(*out_md));
534 			return 0;
535 		}
536 	}
537 	return -ENOENT;
538 }
539 
540 extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
541 	__weak __alias(__efi_mem_desc_lookup);
542 
543 /*
544  * Calculate the highest address of an efi memory descriptor.
545  */
546 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
547 {
548 	u64 size = md->num_pages << EFI_PAGE_SHIFT;
549 	u64 end = md->phys_addr + size;
550 	return end;
551 }
552 
553 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
554 
555 /**
556  * efi_mem_reserve - Reserve an EFI memory region
557  * @addr: Physical address to reserve
558  * @size: Size of reservation
559  *
560  * Mark a region as reserved from general kernel allocation and
561  * prevent it being released by efi_free_boot_services().
562  *
563  * This function should be called drivers once they've parsed EFI
564  * configuration tables to figure out where their data lives, e.g.
565  * efi_esrt_init().
566  */
567 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
568 {
569 	/* efi_mem_reserve() does not work under Xen */
570 	if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
571 		return;
572 
573 	if (!memblock_is_region_reserved(addr, size))
574 		memblock_reserve(addr, size);
575 
576 	/*
577 	 * Some architectures (x86) reserve all boot services ranges
578 	 * until efi_free_boot_services() because of buggy firmware
579 	 * implementations. This means the above memblock_reserve() is
580 	 * superfluous on x86 and instead what it needs to do is
581 	 * ensure the @start, @size is not freed.
582 	 */
583 	efi_arch_mem_reserve(addr, size);
584 }
585 
586 static const efi_config_table_type_t common_tables[] __initconst = {
587 	{ACPI_20_TABLE_GUID,			&efi.acpi20,		"ACPI 2.0"	},
588 	{ACPI_TABLE_GUID,			&efi.acpi,		"ACPI"		},
589 	{SMBIOS_TABLE_GUID,			&efi.smbios,		"SMBIOS"	},
590 	{SMBIOS3_TABLE_GUID,			&efi.smbios3,		"SMBIOS 3.0"	},
591 	{EFI_SYSTEM_RESOURCE_TABLE_GUID,	&efi.esrt,		"ESRT"		},
592 	{EFI_MEMORY_ATTRIBUTES_TABLE_GUID,	&efi_mem_attr_table,	"MEMATTR"	},
593 	{LINUX_EFI_RANDOM_SEED_TABLE_GUID,	&efi_rng_seed,		"RNG"		},
594 	{LINUX_EFI_TPM_EVENT_LOG_GUID,		&efi.tpm_log,		"TPMEventLog"	},
595 	{LINUX_EFI_TPM_FINAL_LOG_GUID,		&efi.tpm_final_log,	"TPMFinalLog"	},
596 	{LINUX_EFI_MEMRESERVE_TABLE_GUID,	&mem_reserve,		"MEMRESERVE"	},
597 	{LINUX_EFI_INITRD_MEDIA_GUID,		&initrd,		"INITRD"	},
598 	{EFI_RT_PROPERTIES_TABLE_GUID,		&rt_prop,		"RTPROP"	},
599 #ifdef CONFIG_EFI_RCI2_TABLE
600 	{DELLEMC_EFI_RCI2_TABLE_GUID,		&rci2_table_phys			},
601 #endif
602 #ifdef CONFIG_LOAD_UEFI_KEYS
603 	{LINUX_EFI_MOK_VARIABLE_TABLE_GUID,	&efi.mokvar_table,	"MOKvar"	},
604 #endif
605 #ifdef CONFIG_EFI_COCO_SECRET
606 	{LINUX_EFI_COCO_SECRET_AREA_GUID,	&efi.coco_secret,	"CocoSecret"	},
607 #endif
608 #ifdef CONFIG_EFI_GENERIC_STUB
609 	{LINUX_EFI_SCREEN_INFO_TABLE_GUID,	&screen_info_table			},
610 #endif
611 	{},
612 };
613 
614 static __init int match_config_table(const efi_guid_t *guid,
615 				     unsigned long table,
616 				     const efi_config_table_type_t *table_types)
617 {
618 	int i;
619 
620 	for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
621 		if (efi_guidcmp(*guid, table_types[i].guid))
622 			continue;
623 
624 		if (!efi_config_table_is_usable(guid, table)) {
625 			if (table_types[i].name[0])
626 				pr_cont("(%s=0x%lx unusable) ",
627 					table_types[i].name, table);
628 			return 1;
629 		}
630 
631 		*(table_types[i].ptr) = table;
632 		if (table_types[i].name[0])
633 			pr_cont("%s=0x%lx ", table_types[i].name, table);
634 		return 1;
635 	}
636 
637 	return 0;
638 }
639 
640 int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
641 				   int count,
642 				   const efi_config_table_type_t *arch_tables)
643 {
644 	const efi_config_table_64_t *tbl64 = (void *)config_tables;
645 	const efi_config_table_32_t *tbl32 = (void *)config_tables;
646 	const efi_guid_t *guid;
647 	unsigned long table;
648 	int i;
649 
650 	pr_info("");
651 	for (i = 0; i < count; i++) {
652 		if (!IS_ENABLED(CONFIG_X86)) {
653 			guid = &config_tables[i].guid;
654 			table = (unsigned long)config_tables[i].table;
655 		} else if (efi_enabled(EFI_64BIT)) {
656 			guid = &tbl64[i].guid;
657 			table = tbl64[i].table;
658 
659 			if (IS_ENABLED(CONFIG_X86_32) &&
660 			    tbl64[i].table > U32_MAX) {
661 				pr_cont("\n");
662 				pr_err("Table located above 4GB, disabling EFI.\n");
663 				return -EINVAL;
664 			}
665 		} else {
666 			guid = &tbl32[i].guid;
667 			table = tbl32[i].table;
668 		}
669 
670 		if (!match_config_table(guid, table, common_tables) && arch_tables)
671 			match_config_table(guid, table, arch_tables);
672 	}
673 	pr_cont("\n");
674 	set_bit(EFI_CONFIG_TABLES, &efi.flags);
675 
676 	if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
677 		struct linux_efi_random_seed *seed;
678 		u32 size = 0;
679 
680 		seed = early_memremap(efi_rng_seed, sizeof(*seed));
681 		if (seed != NULL) {
682 			size = min_t(u32, seed->size, SZ_1K); // sanity check
683 			early_memunmap(seed, sizeof(*seed));
684 		} else {
685 			pr_err("Could not map UEFI random seed!\n");
686 		}
687 		if (size > 0) {
688 			seed = early_memremap(efi_rng_seed,
689 					      sizeof(*seed) + size);
690 			if (seed != NULL) {
691 				add_bootloader_randomness(seed->bits, size);
692 				memzero_explicit(seed->bits, size);
693 				early_memunmap(seed, sizeof(*seed) + size);
694 			} else {
695 				pr_err("Could not map UEFI random seed!\n");
696 			}
697 		}
698 	}
699 
700 	if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
701 		efi_memattr_init();
702 
703 	efi_tpm_eventlog_init();
704 
705 	if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
706 		unsigned long prsv = mem_reserve;
707 
708 		while (prsv) {
709 			struct linux_efi_memreserve *rsv;
710 			u8 *p;
711 
712 			/*
713 			 * Just map a full page: that is what we will get
714 			 * anyway, and it permits us to map the entire entry
715 			 * before knowing its size.
716 			 */
717 			p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
718 					   PAGE_SIZE);
719 			if (p == NULL) {
720 				pr_err("Could not map UEFI memreserve entry!\n");
721 				return -ENOMEM;
722 			}
723 
724 			rsv = (void *)(p + prsv % PAGE_SIZE);
725 
726 			/* reserve the entry itself */
727 			memblock_reserve(prsv,
728 					 struct_size(rsv, entry, rsv->size));
729 
730 			for (i = 0; i < atomic_read(&rsv->count); i++) {
731 				memblock_reserve(rsv->entry[i].base,
732 						 rsv->entry[i].size);
733 			}
734 
735 			prsv = rsv->next;
736 			early_memunmap(p, PAGE_SIZE);
737 		}
738 	}
739 
740 	if (rt_prop != EFI_INVALID_TABLE_ADDR) {
741 		efi_rt_properties_table_t *tbl;
742 
743 		tbl = early_memremap(rt_prop, sizeof(*tbl));
744 		if (tbl) {
745 			efi.runtime_supported_mask &= tbl->runtime_services_supported;
746 			early_memunmap(tbl, sizeof(*tbl));
747 		}
748 	}
749 
750 	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
751 	    initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
752 		struct linux_efi_initrd *tbl;
753 
754 		tbl = early_memremap(initrd, sizeof(*tbl));
755 		if (tbl) {
756 			phys_initrd_start = tbl->base;
757 			phys_initrd_size = tbl->size;
758 			early_memunmap(tbl, sizeof(*tbl));
759 		}
760 	}
761 
762 	return 0;
763 }
764 
765 int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
766 {
767 	if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
768 		pr_err("System table signature incorrect!\n");
769 		return -EINVAL;
770 	}
771 
772 	return 0;
773 }
774 
775 #ifndef CONFIG_IA64
776 static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
777 						size_t size)
778 {
779 	const efi_char16_t *ret;
780 
781 	ret = early_memremap_ro(fw_vendor, size);
782 	if (!ret)
783 		pr_err("Could not map the firmware vendor!\n");
784 	return ret;
785 }
786 
787 static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
788 {
789 	early_memunmap((void *)fw_vendor, size);
790 }
791 #else
792 #define map_fw_vendor(p, s)	__va(p)
793 #define unmap_fw_vendor(v, s)
794 #endif
795 
796 void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
797 				     unsigned long fw_vendor)
798 {
799 	char vendor[100] = "unknown";
800 	const efi_char16_t *c16;
801 	size_t i;
802 	u16 rev;
803 
804 	c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
805 	if (c16) {
806 		for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
807 			vendor[i] = c16[i];
808 		vendor[i] = '\0';
809 
810 		unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
811 	}
812 
813 	rev = (u16)systab_hdr->revision;
814 	pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);
815 
816 	rev %= 10;
817 	if (rev)
818 		pr_cont(".%u", rev);
819 
820 	pr_cont(" by %s\n", vendor);
821 
822 	if (IS_ENABLED(CONFIG_X86_64) &&
823 	    systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
824 	    !strcmp(vendor, "Apple")) {
825 		pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
826 		efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
827 	}
828 }
829 
830 static __initdata char memory_type_name[][13] = {
831 	"Reserved",
832 	"Loader Code",
833 	"Loader Data",
834 	"Boot Code",
835 	"Boot Data",
836 	"Runtime Code",
837 	"Runtime Data",
838 	"Conventional",
839 	"Unusable",
840 	"ACPI Reclaim",
841 	"ACPI Mem NVS",
842 	"MMIO",
843 	"MMIO Port",
844 	"PAL Code",
845 	"Persistent",
846 };
847 
848 char * __init efi_md_typeattr_format(char *buf, size_t size,
849 				     const efi_memory_desc_t *md)
850 {
851 	char *pos;
852 	int type_len;
853 	u64 attr;
854 
855 	pos = buf;
856 	if (md->type >= ARRAY_SIZE(memory_type_name))
857 		type_len = snprintf(pos, size, "[type=%u", md->type);
858 	else
859 		type_len = snprintf(pos, size, "[%-*s",
860 				    (int)(sizeof(memory_type_name[0]) - 1),
861 				    memory_type_name[md->type]);
862 	if (type_len >= size)
863 		return buf;
864 
865 	pos += type_len;
866 	size -= type_len;
867 
868 	attr = md->attribute;
869 	if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
870 		     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
871 		     EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
872 		     EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
873 		     EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
874 		snprintf(pos, size, "|attr=0x%016llx]",
875 			 (unsigned long long)attr);
876 	else
877 		snprintf(pos, size,
878 			 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
879 			 attr & EFI_MEMORY_RUNTIME		? "RUN" : "",
880 			 attr & EFI_MEMORY_MORE_RELIABLE	? "MR"  : "",
881 			 attr & EFI_MEMORY_CPU_CRYPTO   	? "CC"  : "",
882 			 attr & EFI_MEMORY_SP			? "SP"  : "",
883 			 attr & EFI_MEMORY_NV			? "NV"  : "",
884 			 attr & EFI_MEMORY_XP			? "XP"  : "",
885 			 attr & EFI_MEMORY_RP			? "RP"  : "",
886 			 attr & EFI_MEMORY_WP			? "WP"  : "",
887 			 attr & EFI_MEMORY_RO			? "RO"  : "",
888 			 attr & EFI_MEMORY_UCE			? "UCE" : "",
889 			 attr & EFI_MEMORY_WB			? "WB"  : "",
890 			 attr & EFI_MEMORY_WT			? "WT"  : "",
891 			 attr & EFI_MEMORY_WC			? "WC"  : "",
892 			 attr & EFI_MEMORY_UC			? "UC"  : "");
893 	return buf;
894 }
895 
896 /*
897  * IA64 has a funky EFI memory map that doesn't work the same way as
898  * other architectures.
899  */
900 #ifndef CONFIG_IA64
901 /*
902  * efi_mem_attributes - lookup memmap attributes for physical address
903  * @phys_addr: the physical address to lookup
904  *
905  * Search in the EFI memory map for the region covering
906  * @phys_addr. Returns the EFI memory attributes if the region
907  * was found in the memory map, 0 otherwise.
908  */
909 u64 efi_mem_attributes(unsigned long phys_addr)
910 {
911 	efi_memory_desc_t *md;
912 
913 	if (!efi_enabled(EFI_MEMMAP))
914 		return 0;
915 
916 	for_each_efi_memory_desc(md) {
917 		if ((md->phys_addr <= phys_addr) &&
918 		    (phys_addr < (md->phys_addr +
919 		    (md->num_pages << EFI_PAGE_SHIFT))))
920 			return md->attribute;
921 	}
922 	return 0;
923 }
924 
925 /*
926  * efi_mem_type - lookup memmap type for physical address
927  * @phys_addr: the physical address to lookup
928  *
929  * Search in the EFI memory map for the region covering @phys_addr.
930  * Returns the EFI memory type if the region was found in the memory
931  * map, -EINVAL otherwise.
932  */
933 int efi_mem_type(unsigned long phys_addr)
934 {
935 	const efi_memory_desc_t *md;
936 
937 	if (!efi_enabled(EFI_MEMMAP))
938 		return -ENOTSUPP;
939 
940 	for_each_efi_memory_desc(md) {
941 		if ((md->phys_addr <= phys_addr) &&
942 		    (phys_addr < (md->phys_addr +
943 				  (md->num_pages << EFI_PAGE_SHIFT))))
944 			return md->type;
945 	}
946 	return -EINVAL;
947 }
948 #endif
949 
950 int efi_status_to_err(efi_status_t status)
951 {
952 	int err;
953 
954 	switch (status) {
955 	case EFI_SUCCESS:
956 		err = 0;
957 		break;
958 	case EFI_INVALID_PARAMETER:
959 		err = -EINVAL;
960 		break;
961 	case EFI_OUT_OF_RESOURCES:
962 		err = -ENOSPC;
963 		break;
964 	case EFI_DEVICE_ERROR:
965 		err = -EIO;
966 		break;
967 	case EFI_WRITE_PROTECTED:
968 		err = -EROFS;
969 		break;
970 	case EFI_SECURITY_VIOLATION:
971 		err = -EACCES;
972 		break;
973 	case EFI_NOT_FOUND:
974 		err = -ENOENT;
975 		break;
976 	case EFI_ABORTED:
977 		err = -EINTR;
978 		break;
979 	default:
980 		err = -EINVAL;
981 	}
982 
983 	return err;
984 }
985 EXPORT_SYMBOL_GPL(efi_status_to_err);
986 
987 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
988 static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
989 
990 static int __init efi_memreserve_map_root(void)
991 {
992 	if (mem_reserve == EFI_INVALID_TABLE_ADDR)
993 		return -ENODEV;
994 
995 	efi_memreserve_root = memremap(mem_reserve,
996 				       sizeof(*efi_memreserve_root),
997 				       MEMREMAP_WB);
998 	if (WARN_ON_ONCE(!efi_memreserve_root))
999 		return -ENOMEM;
1000 	return 0;
1001 }
1002 
1003 static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
1004 {
1005 	struct resource *res, *parent;
1006 	int ret;
1007 
1008 	res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
1009 	if (!res)
1010 		return -ENOMEM;
1011 
1012 	res->name	= "reserved";
1013 	res->flags	= IORESOURCE_MEM;
1014 	res->start	= addr;
1015 	res->end	= addr + size - 1;
1016 
1017 	/* we expect a conflict with a 'System RAM' region */
1018 	parent = request_resource_conflict(&iomem_resource, res);
1019 	ret = parent ? request_resource(parent, res) : 0;
1020 
1021 	/*
1022 	 * Given that efi_mem_reserve_iomem() can be called at any
1023 	 * time, only call memblock_reserve() if the architecture
1024 	 * keeps the infrastructure around.
1025 	 */
1026 	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
1027 		memblock_reserve(addr, size);
1028 
1029 	return ret;
1030 }
1031 
1032 int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
1033 {
1034 	struct linux_efi_memreserve *rsv;
1035 	unsigned long prsv;
1036 	int rc, index;
1037 
1038 	if (efi_memreserve_root == (void *)ULONG_MAX)
1039 		return -ENODEV;
1040 
1041 	if (!efi_memreserve_root) {
1042 		rc = efi_memreserve_map_root();
1043 		if (rc)
1044 			return rc;
1045 	}
1046 
1047 	/* first try to find a slot in an existing linked list entry */
1048 	for (prsv = efi_memreserve_root->next; prsv; ) {
1049 		rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1050 		if (!rsv)
1051 			return -ENOMEM;
1052 		index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1053 		if (index < rsv->size) {
1054 			rsv->entry[index].base = addr;
1055 			rsv->entry[index].size = size;
1056 
1057 			memunmap(rsv);
1058 			return efi_mem_reserve_iomem(addr, size);
1059 		}
1060 		prsv = rsv->next;
1061 		memunmap(rsv);
1062 	}
1063 
1064 	/* no slot found - allocate a new linked list entry */
1065 	rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1066 	if (!rsv)
1067 		return -ENOMEM;
1068 
1069 	rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1070 	if (rc) {
1071 		free_page((unsigned long)rsv);
1072 		return rc;
1073 	}
1074 
1075 	/*
1076 	 * The memremap() call above assumes that a linux_efi_memreserve entry
1077 	 * never crosses a page boundary, so let's ensure that this remains true
1078 	 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1079 	 * using SZ_4K explicitly in the size calculation below.
1080 	 */
1081 	rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1082 	atomic_set(&rsv->count, 1);
1083 	rsv->entry[0].base = addr;
1084 	rsv->entry[0].size = size;
1085 
1086 	spin_lock(&efi_mem_reserve_persistent_lock);
1087 	rsv->next = efi_memreserve_root->next;
1088 	efi_memreserve_root->next = __pa(rsv);
1089 	spin_unlock(&efi_mem_reserve_persistent_lock);
1090 
1091 	return efi_mem_reserve_iomem(addr, size);
1092 }
1093 
1094 static int __init efi_memreserve_root_init(void)
1095 {
1096 	if (efi_memreserve_root)
1097 		return 0;
1098 	if (efi_memreserve_map_root())
1099 		efi_memreserve_root = (void *)ULONG_MAX;
1100 	return 0;
1101 }
1102 early_initcall(efi_memreserve_root_init);
1103 
1104 #ifdef CONFIG_KEXEC
1105 static int update_efi_random_seed(struct notifier_block *nb,
1106 				  unsigned long code, void *unused)
1107 {
1108 	struct linux_efi_random_seed *seed;
1109 	u32 size = 0;
1110 
1111 	if (!kexec_in_progress)
1112 		return NOTIFY_DONE;
1113 
1114 	seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1115 	if (seed != NULL) {
1116 		size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1117 		memunmap(seed);
1118 	} else {
1119 		pr_err("Could not map UEFI random seed!\n");
1120 	}
1121 	if (size > 0) {
1122 		seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1123 				MEMREMAP_WB);
1124 		if (seed != NULL) {
1125 			seed->size = size;
1126 			get_random_bytes(seed->bits, seed->size);
1127 			memunmap(seed);
1128 		} else {
1129 			pr_err("Could not map UEFI random seed!\n");
1130 		}
1131 	}
1132 	return NOTIFY_DONE;
1133 }
1134 
1135 static struct notifier_block efi_random_seed_nb = {
1136 	.notifier_call = update_efi_random_seed,
1137 };
1138 
1139 static int __init register_update_efi_random_seed(void)
1140 {
1141 	if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1142 		return 0;
1143 	return register_reboot_notifier(&efi_random_seed_nb);
1144 }
1145 late_initcall(register_update_efi_random_seed);
1146 #endif
1147