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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#include <linux/notifier.h>
36
37#include <asm/early_ioremap.h>
38
39struct efi __read_mostly efi = {
40 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
41 .acpi = EFI_INVALID_TABLE_ADDR,
42 .acpi20 = EFI_INVALID_TABLE_ADDR,
43 .smbios = EFI_INVALID_TABLE_ADDR,
44 .smbios3 = EFI_INVALID_TABLE_ADDR,
45 .esrt = EFI_INVALID_TABLE_ADDR,
46 .tpm_log = EFI_INVALID_TABLE_ADDR,
47 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
48#ifdef CONFIG_LOAD_UEFI_KEYS
49 .mokvar_table = EFI_INVALID_TABLE_ADDR,
50#endif
51#ifdef CONFIG_EFI_COCO_SECRET
52 .coco_secret = EFI_INVALID_TABLE_ADDR,
53#endif
54#ifdef CONFIG_UNACCEPTED_MEMORY
55 .unaccepted = EFI_INVALID_TABLE_ADDR,
56#endif
57};
58EXPORT_SYMBOL(efi);
59
60unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
61static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
62static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
63static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
64
65extern unsigned long screen_info_table;
66
67struct mm_struct efi_mm = {
68 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
69 .mm_users = ATOMIC_INIT(2),
70 .mm_count = ATOMIC_INIT(1),
71 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
72 MMAP_LOCK_INITIALIZER(efi_mm)
73 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
74 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
75 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
76};
77
78struct workqueue_struct *efi_rts_wq;
79
80static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
81static int __init setup_noefi(char *arg)
82{
83 disable_runtime = true;
84 return 0;
85}
86early_param("noefi", setup_noefi);
87
88bool efi_runtime_disabled(void)
89{
90 return disable_runtime;
91}
92
93bool __pure __efi_soft_reserve_enabled(void)
94{
95 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
96}
97
98static int __init parse_efi_cmdline(char *str)
99{
100 if (!str) {
101 pr_warn("need at least one option\n");
102 return -EINVAL;
103 }
104
105 if (parse_option_str(str, "debug"))
106 set_bit(EFI_DBG, &efi.flags);
107
108 if (parse_option_str(str, "noruntime"))
109 disable_runtime = true;
110
111 if (parse_option_str(str, "runtime"))
112 disable_runtime = false;
113
114 if (parse_option_str(str, "nosoftreserve"))
115 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
116
117 return 0;
118}
119early_param("efi", parse_efi_cmdline);
120
121struct kobject *efi_kobj;
122
123/*
124 * Let's not leave out systab information that snuck into
125 * the efivars driver
126 * Note, do not add more fields in systab sysfs file as it breaks sysfs
127 * one value per file rule!
128 */
129static ssize_t systab_show(struct kobject *kobj,
130 struct kobj_attribute *attr, char *buf)
131{
132 char *str = buf;
133
134 if (!kobj || !buf)
135 return -EINVAL;
136
137 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
138 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
139 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
140 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
141 /*
142 * If both SMBIOS and SMBIOS3 entry points are implemented, the
143 * SMBIOS3 entry point shall be preferred, so we list it first to
144 * let applications stop parsing after the first match.
145 */
146 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
147 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
148 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
149 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
150
151 if (IS_ENABLED(CONFIG_X86))
152 str = efi_systab_show_arch(str);
153
154 return str - buf;
155}
156
157static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
158
159static ssize_t fw_platform_size_show(struct kobject *kobj,
160 struct kobj_attribute *attr, char *buf)
161{
162 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
163}
164
165extern __weak struct kobj_attribute efi_attr_fw_vendor;
166extern __weak struct kobj_attribute efi_attr_runtime;
167extern __weak struct kobj_attribute efi_attr_config_table;
168static struct kobj_attribute efi_attr_fw_platform_size =
169 __ATTR_RO(fw_platform_size);
170
171static struct attribute *efi_subsys_attrs[] = {
172 &efi_attr_systab.attr,
173 &efi_attr_fw_platform_size.attr,
174 &efi_attr_fw_vendor.attr,
175 &efi_attr_runtime.attr,
176 &efi_attr_config_table.attr,
177 NULL,
178};
179
180umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
181 int n)
182{
183 return attr->mode;
184}
185
186static const struct attribute_group efi_subsys_attr_group = {
187 .attrs = efi_subsys_attrs,
188 .is_visible = efi_attr_is_visible,
189};
190
191struct blocking_notifier_head efivar_ops_nh;
192EXPORT_SYMBOL_GPL(efivar_ops_nh);
193
194static struct efivars generic_efivars;
195static struct efivar_operations generic_ops;
196
197static bool generic_ops_supported(void)
198{
199 unsigned long name_size;
200 efi_status_t status;
201 efi_char16_t name;
202 efi_guid_t guid;
203
204 name_size = sizeof(name);
205
206 if (!efi.get_next_variable)
207 return false;
208 status = efi.get_next_variable(&name_size, &name, &guid);
209 if (status == EFI_UNSUPPORTED)
210 return false;
211
212 return true;
213}
214
215static int generic_ops_register(void)
216{
217 if (!generic_ops_supported())
218 return 0;
219
220 generic_ops.get_variable = efi.get_variable;
221 generic_ops.get_next_variable = efi.get_next_variable;
222 generic_ops.query_variable_store = efi_query_variable_store;
223 generic_ops.query_variable_info = efi.query_variable_info;
224
225 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
226 generic_ops.set_variable = efi.set_variable;
227 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
228 }
229 return efivars_register(&generic_efivars, &generic_ops);
230}
231
232static void generic_ops_unregister(void)
233{
234 if (!generic_ops.get_variable)
235 return;
236
237 efivars_unregister(&generic_efivars);
238}
239
240void efivars_generic_ops_register(void)
241{
242 generic_ops_register();
243}
244EXPORT_SYMBOL_GPL(efivars_generic_ops_register);
245
246void efivars_generic_ops_unregister(void)
247{
248 generic_ops_unregister();
249}
250EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister);
251
252#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
253#define EFIVAR_SSDT_NAME_MAX 16UL
254static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
255static int __init efivar_ssdt_setup(char *str)
256{
257 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
258
259 if (ret)
260 return ret;
261
262 if (strlen(str) < sizeof(efivar_ssdt))
263 memcpy(efivar_ssdt, str, strlen(str));
264 else
265 pr_warn("efivar_ssdt: name too long: %s\n", str);
266 return 1;
267}
268__setup("efivar_ssdt=", efivar_ssdt_setup);
269
270static __init int efivar_ssdt_load(void)
271{
272 unsigned long name_size = 256;
273 efi_char16_t *name = NULL;
274 efi_status_t status;
275 efi_guid_t guid;
276
277 if (!efivar_ssdt[0])
278 return 0;
279
280 name = kzalloc(name_size, GFP_KERNEL);
281 if (!name)
282 return -ENOMEM;
283
284 for (;;) {
285 char utf8_name[EFIVAR_SSDT_NAME_MAX];
286 unsigned long data_size = 0;
287 void *data;
288 int limit;
289
290 status = efi.get_next_variable(&name_size, name, &guid);
291 if (status == EFI_NOT_FOUND) {
292 break;
293 } else if (status == EFI_BUFFER_TOO_SMALL) {
294 efi_char16_t *name_tmp =
295 krealloc(name, name_size, GFP_KERNEL);
296 if (!name_tmp) {
297 kfree(name);
298 return -ENOMEM;
299 }
300 name = name_tmp;
301 continue;
302 }
303
304 limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
305 ucs2_as_utf8(utf8_name, name, limit - 1);
306 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
307 continue;
308
309 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
310
311 status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
312 if (status != EFI_BUFFER_TOO_SMALL || !data_size)
313 return -EIO;
314
315 data = kmalloc(data_size, GFP_KERNEL);
316 if (!data)
317 return -ENOMEM;
318
319 status = efi.get_variable(name, &guid, NULL, &data_size, data);
320 if (status == EFI_SUCCESS) {
321 acpi_status ret = acpi_load_table(data, NULL);
322 if (ret)
323 pr_err("failed to load table: %u\n", ret);
324 else
325 continue;
326 } else {
327 pr_err("failed to get var data: 0x%lx\n", status);
328 }
329 kfree(data);
330 }
331 return 0;
332}
333#else
334static inline int efivar_ssdt_load(void) { return 0; }
335#endif
336
337#ifdef CONFIG_DEBUG_FS
338
339#define EFI_DEBUGFS_MAX_BLOBS 32
340
341static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
342
343static void __init efi_debugfs_init(void)
344{
345 struct dentry *efi_debugfs;
346 efi_memory_desc_t *md;
347 char name[32];
348 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
349 int i = 0;
350
351 efi_debugfs = debugfs_create_dir("efi", NULL);
352 if (IS_ERR_OR_NULL(efi_debugfs))
353 return;
354
355 for_each_efi_memory_desc(md) {
356 switch (md->type) {
357 case EFI_BOOT_SERVICES_CODE:
358 snprintf(name, sizeof(name), "boot_services_code%d",
359 type_count[md->type]++);
360 break;
361 case EFI_BOOT_SERVICES_DATA:
362 snprintf(name, sizeof(name), "boot_services_data%d",
363 type_count[md->type]++);
364 break;
365 default:
366 continue;
367 }
368
369 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
370 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
371 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
372 break;
373 }
374
375 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
376 debugfs_blob[i].data = memremap(md->phys_addr,
377 debugfs_blob[i].size,
378 MEMREMAP_WB);
379 if (!debugfs_blob[i].data)
380 continue;
381
382 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
383 i++;
384 }
385}
386#else
387static inline void efi_debugfs_init(void) {}
388#endif
389
390/*
391 * We register the efi subsystem with the firmware subsystem and the
392 * efivars subsystem with the efi subsystem, if the system was booted with
393 * EFI.
394 */
395static int __init efisubsys_init(void)
396{
397 int error;
398
399 if (!efi_enabled(EFI_RUNTIME_SERVICES))
400 efi.runtime_supported_mask = 0;
401
402 if (!efi_enabled(EFI_BOOT))
403 return 0;
404
405 if (efi.runtime_supported_mask) {
406 /*
407 * Since we process only one efi_runtime_service() at a time, an
408 * ordered workqueue (which creates only one execution context)
409 * should suffice for all our needs.
410 */
411 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
412 if (!efi_rts_wq) {
413 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
414 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
415 efi.runtime_supported_mask = 0;
416 return 0;
417 }
418 }
419
420 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
421 platform_device_register_simple("rtc-efi", 0, NULL, 0);
422
423 /* We register the efi directory at /sys/firmware/efi */
424 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
425 if (!efi_kobj) {
426 pr_err("efi: Firmware registration failed.\n");
427 error = -ENOMEM;
428 goto err_destroy_wq;
429 }
430
431 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
432 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
433 error = generic_ops_register();
434 if (error)
435 goto err_put;
436 efivar_ssdt_load();
437 platform_device_register_simple("efivars", 0, NULL, 0);
438 }
439
440 BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh);
441
442 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
443 if (error) {
444 pr_err("efi: Sysfs attribute export failed with error %d.\n",
445 error);
446 goto err_unregister;
447 }
448
449 /* and the standard mountpoint for efivarfs */
450 error = sysfs_create_mount_point(efi_kobj, "efivars");
451 if (error) {
452 pr_err("efivars: Subsystem registration failed.\n");
453 goto err_remove_group;
454 }
455
456 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
457 efi_debugfs_init();
458
459#ifdef CONFIG_EFI_COCO_SECRET
460 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
461 platform_device_register_simple("efi_secret", 0, NULL, 0);
462#endif
463
464 return 0;
465
466err_remove_group:
467 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
468err_unregister:
469 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
470 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
471 generic_ops_unregister();
472err_put:
473 kobject_put(efi_kobj);
474 efi_kobj = NULL;
475err_destroy_wq:
476 if (efi_rts_wq)
477 destroy_workqueue(efi_rts_wq);
478
479 return error;
480}
481
482subsys_initcall(efisubsys_init);
483
484void __init efi_find_mirror(void)
485{
486 efi_memory_desc_t *md;
487 u64 mirror_size = 0, total_size = 0;
488
489 if (!efi_enabled(EFI_MEMMAP))
490 return;
491
492 for_each_efi_memory_desc(md) {
493 unsigned long long start = md->phys_addr;
494 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
495
496 total_size += size;
497 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
498 memblock_mark_mirror(start, size);
499 mirror_size += size;
500 }
501 }
502 if (mirror_size)
503 pr_info("Memory: %lldM/%lldM mirrored memory\n",
504 mirror_size>>20, total_size>>20);
505}
506
507/*
508 * Find the efi memory descriptor for a given physical address. Given a
509 * physical address, determine if it exists within an EFI Memory Map entry,
510 * and if so, populate the supplied memory descriptor with the appropriate
511 * data.
512 */
513int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
514{
515 efi_memory_desc_t *md;
516
517 if (!efi_enabled(EFI_MEMMAP)) {
518 pr_err_once("EFI_MEMMAP is not enabled.\n");
519 return -EINVAL;
520 }
521
522 if (!out_md) {
523 pr_err_once("out_md is null.\n");
524 return -EINVAL;
525 }
526
527 for_each_efi_memory_desc(md) {
528 u64 size;
529 u64 end;
530
531 /* skip bogus entries (including empty ones) */
532 if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
533 (md->num_pages <= 0) ||
534 (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
535 continue;
536
537 size = md->num_pages << EFI_PAGE_SHIFT;
538 end = md->phys_addr + size;
539 if (phys_addr >= md->phys_addr && phys_addr < end) {
540 memcpy(out_md, md, sizeof(*out_md));
541 return 0;
542 }
543 }
544 return -ENOENT;
545}
546
547extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
548 __weak __alias(__efi_mem_desc_lookup);
549
550/*
551 * Calculate the highest address of an efi memory descriptor.
552 */
553u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
554{
555 u64 size = md->num_pages << EFI_PAGE_SHIFT;
556 u64 end = md->phys_addr + size;
557 return end;
558}
559
560void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
561
562/**
563 * efi_mem_reserve - Reserve an EFI memory region
564 * @addr: Physical address to reserve
565 * @size: Size of reservation
566 *
567 * Mark a region as reserved from general kernel allocation and
568 * prevent it being released by efi_free_boot_services().
569 *
570 * This function should be called drivers once they've parsed EFI
571 * configuration tables to figure out where their data lives, e.g.
572 * efi_esrt_init().
573 */
574void __init efi_mem_reserve(phys_addr_t addr, u64 size)
575{
576 /* efi_mem_reserve() does not work under Xen */
577 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
578 return;
579
580 if (!memblock_is_region_reserved(addr, size))
581 memblock_reserve(addr, size);
582
583 /*
584 * Some architectures (x86) reserve all boot services ranges
585 * until efi_free_boot_services() because of buggy firmware
586 * implementations. This means the above memblock_reserve() is
587 * superfluous on x86 and instead what it needs to do is
588 * ensure the @start, @size is not freed.
589 */
590 efi_arch_mem_reserve(addr, size);
591}
592
593static const efi_config_table_type_t common_tables[] __initconst = {
594 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
595 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
596 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
597 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
598 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
599 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
600 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
601 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
602 {EFI_TCG2_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "TPMFinalLog" },
603 {EFI_CC_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "CCFinalLog" },
604 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
605 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
606 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
607#ifdef CONFIG_EFI_RCI2_TABLE
608 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
609#endif
610#ifdef CONFIG_LOAD_UEFI_KEYS
611 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
612#endif
613#ifdef CONFIG_EFI_COCO_SECRET
614 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" },
615#endif
616#ifdef CONFIG_UNACCEPTED_MEMORY
617 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" },
618#endif
619#ifdef CONFIG_EFI_GENERIC_STUB
620 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table },
621#endif
622 {},
623};
624
625static __init int match_config_table(const efi_guid_t *guid,
626 unsigned long table,
627 const efi_config_table_type_t *table_types)
628{
629 int i;
630
631 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
632 if (efi_guidcmp(*guid, table_types[i].guid))
633 continue;
634
635 if (!efi_config_table_is_usable(guid, table)) {
636 if (table_types[i].name[0])
637 pr_cont("(%s=0x%lx unusable) ",
638 table_types[i].name, table);
639 return 1;
640 }
641
642 *(table_types[i].ptr) = table;
643 if (table_types[i].name[0])
644 pr_cont("%s=0x%lx ", table_types[i].name, table);
645 return 1;
646 }
647
648 return 0;
649}
650
651/**
652 * reserve_unaccepted - Map and reserve unaccepted configuration table
653 * @unaccepted: Pointer to unaccepted memory table
654 *
655 * memblock_add() makes sure that the table is mapped in direct mapping. During
656 * normal boot it happens automatically because the table is allocated from
657 * usable memory. But during crashkernel boot only memory specifically reserved
658 * for crash scenario is mapped. memblock_add() forces the table to be mapped
659 * in crashkernel case.
660 *
661 * Align the range to the nearest page borders. Ranges smaller than page size
662 * are not going to be mapped.
663 *
664 * memblock_reserve() makes sure that future allocations will not touch the
665 * table.
666 */
667
668static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
669{
670 phys_addr_t start, size;
671
672 start = PAGE_ALIGN_DOWN(efi.unaccepted);
673 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size);
674
675 memblock_add(start, size);
676 memblock_reserve(start, size);
677}
678
679int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
680 int count,
681 const efi_config_table_type_t *arch_tables)
682{
683 const efi_config_table_64_t *tbl64 = (void *)config_tables;
684 const efi_config_table_32_t *tbl32 = (void *)config_tables;
685 const efi_guid_t *guid;
686 unsigned long table;
687 int i;
688
689 pr_info("");
690 for (i = 0; i < count; i++) {
691 if (!IS_ENABLED(CONFIG_X86)) {
692 guid = &config_tables[i].guid;
693 table = (unsigned long)config_tables[i].table;
694 } else if (efi_enabled(EFI_64BIT)) {
695 guid = &tbl64[i].guid;
696 table = tbl64[i].table;
697
698 if (IS_ENABLED(CONFIG_X86_32) &&
699 tbl64[i].table > U32_MAX) {
700 pr_cont("\n");
701 pr_err("Table located above 4GB, disabling EFI.\n");
702 return -EINVAL;
703 }
704 } else {
705 guid = &tbl32[i].guid;
706 table = tbl32[i].table;
707 }
708
709 if (!match_config_table(guid, table, common_tables) && arch_tables)
710 match_config_table(guid, table, arch_tables);
711 }
712 pr_cont("\n");
713 set_bit(EFI_CONFIG_TABLES, &efi.flags);
714
715 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
716 struct linux_efi_random_seed *seed;
717 u32 size = 0;
718
719 seed = early_memremap(efi_rng_seed, sizeof(*seed));
720 if (seed != NULL) {
721 size = min_t(u32, seed->size, SZ_1K); // sanity check
722 early_memunmap(seed, sizeof(*seed));
723 } else {
724 pr_err("Could not map UEFI random seed!\n");
725 }
726 if (size > 0) {
727 seed = early_memremap(efi_rng_seed,
728 sizeof(*seed) + size);
729 if (seed != NULL) {
730 add_bootloader_randomness(seed->bits, size);
731 memzero_explicit(seed->bits, size);
732 early_memunmap(seed, sizeof(*seed) + size);
733 } else {
734 pr_err("Could not map UEFI random seed!\n");
735 }
736 }
737 }
738
739 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
740 efi_memattr_init();
741
742 efi_tpm_eventlog_init();
743
744 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
745 unsigned long prsv = mem_reserve;
746
747 while (prsv) {
748 struct linux_efi_memreserve *rsv;
749 u8 *p;
750
751 /*
752 * Just map a full page: that is what we will get
753 * anyway, and it permits us to map the entire entry
754 * before knowing its size.
755 */
756 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
757 PAGE_SIZE);
758 if (p == NULL) {
759 pr_err("Could not map UEFI memreserve entry!\n");
760 return -ENOMEM;
761 }
762
763 rsv = (void *)(p + prsv % PAGE_SIZE);
764
765 /* reserve the entry itself */
766 memblock_reserve(prsv,
767 struct_size(rsv, entry, rsv->size));
768
769 for (i = 0; i < atomic_read(&rsv->count); i++) {
770 memblock_reserve(rsv->entry[i].base,
771 rsv->entry[i].size);
772 }
773
774 prsv = rsv->next;
775 early_memunmap(p, PAGE_SIZE);
776 }
777 }
778
779 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
780 efi_rt_properties_table_t *tbl;
781
782 tbl = early_memremap(rt_prop, sizeof(*tbl));
783 if (tbl) {
784 efi.runtime_supported_mask &= tbl->runtime_services_supported;
785 early_memunmap(tbl, sizeof(*tbl));
786 }
787 }
788
789 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
790 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
791 struct linux_efi_initrd *tbl;
792
793 tbl = early_memremap(initrd, sizeof(*tbl));
794 if (tbl) {
795 phys_initrd_start = tbl->base;
796 phys_initrd_size = tbl->size;
797 early_memunmap(tbl, sizeof(*tbl));
798 }
799 }
800
801 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) &&
802 efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
803 struct efi_unaccepted_memory *unaccepted;
804
805 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted));
806 if (unaccepted) {
807
808 if (unaccepted->version == 1) {
809 reserve_unaccepted(unaccepted);
810 } else {
811 efi.unaccepted = EFI_INVALID_TABLE_ADDR;
812 }
813
814 early_memunmap(unaccepted, sizeof(*unaccepted));
815 }
816 }
817
818 return 0;
819}
820
821int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
822{
823 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
824 pr_err("System table signature incorrect!\n");
825 return -EINVAL;
826 }
827
828 return 0;
829}
830
831static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
832 size_t size)
833{
834 const efi_char16_t *ret;
835
836 ret = early_memremap_ro(fw_vendor, size);
837 if (!ret)
838 pr_err("Could not map the firmware vendor!\n");
839 return ret;
840}
841
842static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
843{
844 early_memunmap((void *)fw_vendor, size);
845}
846
847void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
848 unsigned long fw_vendor)
849{
850 char vendor[100] = "unknown";
851 const efi_char16_t *c16;
852 size_t i;
853 u16 rev;
854
855 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
856 if (c16) {
857 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
858 vendor[i] = c16[i];
859 vendor[i] = '\0';
860
861 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
862 }
863
864 rev = (u16)systab_hdr->revision;
865 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);
866
867 rev %= 10;
868 if (rev)
869 pr_cont(".%u", rev);
870
871 pr_cont(" by %s\n", vendor);
872
873 if (IS_ENABLED(CONFIG_X86_64) &&
874 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
875 !strcmp(vendor, "Apple")) {
876 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
877 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
878 }
879}
880
881static __initdata char memory_type_name[][13] = {
882 "Reserved",
883 "Loader Code",
884 "Loader Data",
885 "Boot Code",
886 "Boot Data",
887 "Runtime Code",
888 "Runtime Data",
889 "Conventional",
890 "Unusable",
891 "ACPI Reclaim",
892 "ACPI Mem NVS",
893 "MMIO",
894 "MMIO Port",
895 "PAL Code",
896 "Persistent",
897 "Unaccepted",
898};
899
900char * __init efi_md_typeattr_format(char *buf, size_t size,
901 const efi_memory_desc_t *md)
902{
903 char *pos;
904 int type_len;
905 u64 attr;
906
907 pos = buf;
908 if (md->type >= ARRAY_SIZE(memory_type_name))
909 type_len = snprintf(pos, size, "[type=%u", md->type);
910 else
911 type_len = snprintf(pos, size, "[%-*s",
912 (int)(sizeof(memory_type_name[0]) - 1),
913 memory_type_name[md->type]);
914 if (type_len >= size)
915 return buf;
916
917 pos += type_len;
918 size -= type_len;
919
920 attr = md->attribute;
921 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
922 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
923 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
924 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
925 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
926 snprintf(pos, size, "|attr=0x%016llx]",
927 (unsigned long long)attr);
928 else
929 snprintf(pos, size,
930 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
931 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
932 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
933 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
934 attr & EFI_MEMORY_SP ? "SP" : "",
935 attr & EFI_MEMORY_NV ? "NV" : "",
936 attr & EFI_MEMORY_XP ? "XP" : "",
937 attr & EFI_MEMORY_RP ? "RP" : "",
938 attr & EFI_MEMORY_WP ? "WP" : "",
939 attr & EFI_MEMORY_RO ? "RO" : "",
940 attr & EFI_MEMORY_UCE ? "UCE" : "",
941 attr & EFI_MEMORY_WB ? "WB" : "",
942 attr & EFI_MEMORY_WT ? "WT" : "",
943 attr & EFI_MEMORY_WC ? "WC" : "",
944 attr & EFI_MEMORY_UC ? "UC" : "");
945 return buf;
946}
947
948/*
949 * efi_mem_attributes - lookup memmap attributes for physical address
950 * @phys_addr: the physical address to lookup
951 *
952 * Search in the EFI memory map for the region covering
953 * @phys_addr. Returns the EFI memory attributes if the region
954 * was found in the memory map, 0 otherwise.
955 */
956u64 efi_mem_attributes(unsigned long phys_addr)
957{
958 efi_memory_desc_t *md;
959
960 if (!efi_enabled(EFI_MEMMAP))
961 return 0;
962
963 for_each_efi_memory_desc(md) {
964 if ((md->phys_addr <= phys_addr) &&
965 (phys_addr < (md->phys_addr +
966 (md->num_pages << EFI_PAGE_SHIFT))))
967 return md->attribute;
968 }
969 return 0;
970}
971
972/*
973 * efi_mem_type - lookup memmap type for physical address
974 * @phys_addr: the physical address to lookup
975 *
976 * Search in the EFI memory map for the region covering @phys_addr.
977 * Returns the EFI memory type if the region was found in the memory
978 * map, -EINVAL otherwise.
979 */
980int efi_mem_type(unsigned long phys_addr)
981{
982 const efi_memory_desc_t *md;
983
984 if (!efi_enabled(EFI_MEMMAP))
985 return -ENOTSUPP;
986
987 for_each_efi_memory_desc(md) {
988 if ((md->phys_addr <= phys_addr) &&
989 (phys_addr < (md->phys_addr +
990 (md->num_pages << EFI_PAGE_SHIFT))))
991 return md->type;
992 }
993 return -EINVAL;
994}
995
996int efi_status_to_err(efi_status_t status)
997{
998 int err;
999
1000 switch (status) {
1001 case EFI_SUCCESS:
1002 err = 0;
1003 break;
1004 case EFI_INVALID_PARAMETER:
1005 err = -EINVAL;
1006 break;
1007 case EFI_OUT_OF_RESOURCES:
1008 err = -ENOSPC;
1009 break;
1010 case EFI_DEVICE_ERROR:
1011 err = -EIO;
1012 break;
1013 case EFI_WRITE_PROTECTED:
1014 err = -EROFS;
1015 break;
1016 case EFI_SECURITY_VIOLATION:
1017 err = -EACCES;
1018 break;
1019 case EFI_NOT_FOUND:
1020 err = -ENOENT;
1021 break;
1022 case EFI_ABORTED:
1023 err = -EINTR;
1024 break;
1025 default:
1026 err = -EINVAL;
1027 }
1028
1029 return err;
1030}
1031EXPORT_SYMBOL_GPL(efi_status_to_err);
1032
1033static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
1034static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
1035
1036static int __init efi_memreserve_map_root(void)
1037{
1038 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
1039 return -ENODEV;
1040
1041 efi_memreserve_root = memremap(mem_reserve,
1042 sizeof(*efi_memreserve_root),
1043 MEMREMAP_WB);
1044 if (WARN_ON_ONCE(!efi_memreserve_root))
1045 return -ENOMEM;
1046 return 0;
1047}
1048
1049static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
1050{
1051 struct resource *res, *parent;
1052 int ret;
1053
1054 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
1055 if (!res)
1056 return -ENOMEM;
1057
1058 res->name = "reserved";
1059 res->flags = IORESOURCE_MEM;
1060 res->start = addr;
1061 res->end = addr + size - 1;
1062
1063 /* we expect a conflict with a 'System RAM' region */
1064 parent = request_resource_conflict(&iomem_resource, res);
1065 ret = parent ? request_resource(parent, res) : 0;
1066
1067 /*
1068 * Given that efi_mem_reserve_iomem() can be called at any
1069 * time, only call memblock_reserve() if the architecture
1070 * keeps the infrastructure around.
1071 */
1072 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
1073 memblock_reserve(addr, size);
1074
1075 return ret;
1076}
1077
1078int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
1079{
1080 struct linux_efi_memreserve *rsv;
1081 unsigned long prsv;
1082 int rc, index;
1083
1084 if (efi_memreserve_root == (void *)ULONG_MAX)
1085 return -ENODEV;
1086
1087 if (!efi_memreserve_root) {
1088 rc = efi_memreserve_map_root();
1089 if (rc)
1090 return rc;
1091 }
1092
1093 /* first try to find a slot in an existing linked list entry */
1094 for (prsv = efi_memreserve_root->next; prsv; ) {
1095 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1096 if (!rsv)
1097 return -ENOMEM;
1098 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1099 if (index < rsv->size) {
1100 rsv->entry[index].base = addr;
1101 rsv->entry[index].size = size;
1102
1103 memunmap(rsv);
1104 return efi_mem_reserve_iomem(addr, size);
1105 }
1106 prsv = rsv->next;
1107 memunmap(rsv);
1108 }
1109
1110 /* no slot found - allocate a new linked list entry */
1111 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1112 if (!rsv)
1113 return -ENOMEM;
1114
1115 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1116 if (rc) {
1117 free_page((unsigned long)rsv);
1118 return rc;
1119 }
1120
1121 /*
1122 * The memremap() call above assumes that a linux_efi_memreserve entry
1123 * never crosses a page boundary, so let's ensure that this remains true
1124 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1125 * using SZ_4K explicitly in the size calculation below.
1126 */
1127 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1128 atomic_set(&rsv->count, 1);
1129 rsv->entry[0].base = addr;
1130 rsv->entry[0].size = size;
1131
1132 spin_lock(&efi_mem_reserve_persistent_lock);
1133 rsv->next = efi_memreserve_root->next;
1134 efi_memreserve_root->next = __pa(rsv);
1135 spin_unlock(&efi_mem_reserve_persistent_lock);
1136
1137 return efi_mem_reserve_iomem(addr, size);
1138}
1139
1140static int __init efi_memreserve_root_init(void)
1141{
1142 if (efi_memreserve_root)
1143 return 0;
1144 if (efi_memreserve_map_root())
1145 efi_memreserve_root = (void *)ULONG_MAX;
1146 return 0;
1147}
1148early_initcall(efi_memreserve_root_init);
1149
1150#ifdef CONFIG_KEXEC
1151static int update_efi_random_seed(struct notifier_block *nb,
1152 unsigned long code, void *unused)
1153{
1154 struct linux_efi_random_seed *seed;
1155 u32 size = 0;
1156
1157 if (!kexec_in_progress)
1158 return NOTIFY_DONE;
1159
1160 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1161 if (seed != NULL) {
1162 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1163 memunmap(seed);
1164 } else {
1165 pr_err("Could not map UEFI random seed!\n");
1166 }
1167 if (size > 0) {
1168 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1169 MEMREMAP_WB);
1170 if (seed != NULL) {
1171 seed->size = size;
1172 get_random_bytes(seed->bits, seed->size);
1173 memunmap(seed);
1174 } else {
1175 pr_err("Could not map UEFI random seed!\n");
1176 }
1177 }
1178 return NOTIFY_DONE;
1179}
1180
1181static struct notifier_block efi_random_seed_nb = {
1182 .notifier_call = update_efi_random_seed,
1183};
1184
1185static int __init register_update_efi_random_seed(void)
1186{
1187 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1188 return 0;
1189 return register_reboot_notifier(&efi_random_seed_nb);
1190}
1191late_initcall(register_update_efi_random_seed);
1192#endif
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#include <linux/notifier.h>
36
37#include <asm/early_ioremap.h>
38
39struct efi __read_mostly efi = {
40 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
41 .acpi = EFI_INVALID_TABLE_ADDR,
42 .acpi20 = EFI_INVALID_TABLE_ADDR,
43 .smbios = EFI_INVALID_TABLE_ADDR,
44 .smbios3 = EFI_INVALID_TABLE_ADDR,
45 .esrt = EFI_INVALID_TABLE_ADDR,
46 .tpm_log = EFI_INVALID_TABLE_ADDR,
47 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
48#ifdef CONFIG_LOAD_UEFI_KEYS
49 .mokvar_table = EFI_INVALID_TABLE_ADDR,
50#endif
51#ifdef CONFIG_EFI_COCO_SECRET
52 .coco_secret = EFI_INVALID_TABLE_ADDR,
53#endif
54#ifdef CONFIG_UNACCEPTED_MEMORY
55 .unaccepted = EFI_INVALID_TABLE_ADDR,
56#endif
57};
58EXPORT_SYMBOL(efi);
59
60unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
61static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
62static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
63static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
64
65extern unsigned long screen_info_table;
66
67struct mm_struct efi_mm = {
68 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
69 .mm_users = ATOMIC_INIT(2),
70 .mm_count = ATOMIC_INIT(1),
71 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
72 MMAP_LOCK_INITIALIZER(efi_mm)
73 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
74 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
75 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
76};
77
78struct workqueue_struct *efi_rts_wq;
79
80static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
81static int __init setup_noefi(char *arg)
82{
83 disable_runtime = true;
84 return 0;
85}
86early_param("noefi", setup_noefi);
87
88bool efi_runtime_disabled(void)
89{
90 return disable_runtime;
91}
92
93bool __pure __efi_soft_reserve_enabled(void)
94{
95 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
96}
97
98static int __init parse_efi_cmdline(char *str)
99{
100 if (!str) {
101 pr_warn("need at least one option\n");
102 return -EINVAL;
103 }
104
105 if (parse_option_str(str, "debug"))
106 set_bit(EFI_DBG, &efi.flags);
107
108 if (parse_option_str(str, "noruntime"))
109 disable_runtime = true;
110
111 if (parse_option_str(str, "runtime"))
112 disable_runtime = false;
113
114 if (parse_option_str(str, "nosoftreserve"))
115 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
116
117 return 0;
118}
119early_param("efi", parse_efi_cmdline);
120
121struct kobject *efi_kobj;
122
123/*
124 * Let's not leave out systab information that snuck into
125 * the efivars driver
126 * Note, do not add more fields in systab sysfs file as it breaks sysfs
127 * one value per file rule!
128 */
129static ssize_t systab_show(struct kobject *kobj,
130 struct kobj_attribute *attr, char *buf)
131{
132 char *str = buf;
133
134 if (!kobj || !buf)
135 return -EINVAL;
136
137 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
138 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
139 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
140 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
141 /*
142 * If both SMBIOS and SMBIOS3 entry points are implemented, the
143 * SMBIOS3 entry point shall be preferred, so we list it first to
144 * let applications stop parsing after the first match.
145 */
146 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
147 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
148 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
149 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
150
151 if (IS_ENABLED(CONFIG_X86))
152 str = efi_systab_show_arch(str);
153
154 return str - buf;
155}
156
157static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
158
159static ssize_t fw_platform_size_show(struct kobject *kobj,
160 struct kobj_attribute *attr, char *buf)
161{
162 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
163}
164
165extern __weak struct kobj_attribute efi_attr_fw_vendor;
166extern __weak struct kobj_attribute efi_attr_runtime;
167extern __weak struct kobj_attribute efi_attr_config_table;
168static struct kobj_attribute efi_attr_fw_platform_size =
169 __ATTR_RO(fw_platform_size);
170
171static struct attribute *efi_subsys_attrs[] = {
172 &efi_attr_systab.attr,
173 &efi_attr_fw_platform_size.attr,
174 &efi_attr_fw_vendor.attr,
175 &efi_attr_runtime.attr,
176 &efi_attr_config_table.attr,
177 NULL,
178};
179
180umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
181 int n)
182{
183 return attr->mode;
184}
185
186static const struct attribute_group efi_subsys_attr_group = {
187 .attrs = efi_subsys_attrs,
188 .is_visible = efi_attr_is_visible,
189};
190
191struct blocking_notifier_head efivar_ops_nh;
192EXPORT_SYMBOL_GPL(efivar_ops_nh);
193
194static struct efivars generic_efivars;
195static struct efivar_operations generic_ops;
196
197static bool generic_ops_supported(void)
198{
199 unsigned long name_size;
200 efi_status_t status;
201 efi_char16_t name;
202 efi_guid_t guid;
203
204 name_size = sizeof(name);
205
206 if (!efi.get_next_variable)
207 return false;
208 status = efi.get_next_variable(&name_size, &name, &guid);
209 if (status == EFI_UNSUPPORTED)
210 return false;
211
212 return true;
213}
214
215static int generic_ops_register(void)
216{
217 if (!generic_ops_supported())
218 return 0;
219
220 generic_ops.get_variable = efi.get_variable;
221 generic_ops.get_next_variable = efi.get_next_variable;
222 generic_ops.query_variable_store = efi_query_variable_store;
223 generic_ops.query_variable_info = efi.query_variable_info;
224
225 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
226 generic_ops.set_variable = efi.set_variable;
227 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
228 }
229 return efivars_register(&generic_efivars, &generic_ops);
230}
231
232static void generic_ops_unregister(void)
233{
234 if (!generic_ops.get_variable)
235 return;
236
237 efivars_unregister(&generic_efivars);
238}
239
240void efivars_generic_ops_register(void)
241{
242 generic_ops_register();
243}
244EXPORT_SYMBOL_GPL(efivars_generic_ops_register);
245
246void efivars_generic_ops_unregister(void)
247{
248 generic_ops_unregister();
249}
250EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister);
251
252#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
253#define EFIVAR_SSDT_NAME_MAX 16UL
254static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
255static int __init efivar_ssdt_setup(char *str)
256{
257 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
258
259 if (ret)
260 return ret;
261
262 if (strlen(str) < sizeof(efivar_ssdt))
263 memcpy(efivar_ssdt, str, strlen(str));
264 else
265 pr_warn("efivar_ssdt: name too long: %s\n", str);
266 return 1;
267}
268__setup("efivar_ssdt=", efivar_ssdt_setup);
269
270static __init int efivar_ssdt_load(void)
271{
272 unsigned long name_size = 256;
273 efi_char16_t *name = NULL;
274 efi_status_t status;
275 efi_guid_t guid;
276 int ret = 0;
277
278 if (!efivar_ssdt[0])
279 return 0;
280
281 name = kzalloc(name_size, GFP_KERNEL);
282 if (!name)
283 return -ENOMEM;
284
285 for (;;) {
286 char utf8_name[EFIVAR_SSDT_NAME_MAX];
287 unsigned long data_size = 0;
288 void *data;
289 int limit;
290
291 status = efi.get_next_variable(&name_size, name, &guid);
292 if (status == EFI_NOT_FOUND) {
293 break;
294 } else if (status == EFI_BUFFER_TOO_SMALL) {
295 efi_char16_t *name_tmp =
296 krealloc(name, name_size, GFP_KERNEL);
297 if (!name_tmp) {
298 ret = -ENOMEM;
299 goto out;
300 }
301 name = name_tmp;
302 continue;
303 }
304
305 limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
306 ucs2_as_utf8(utf8_name, name, limit - 1);
307 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
308 continue;
309
310 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
311
312 status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
313 if (status != EFI_BUFFER_TOO_SMALL || !data_size) {
314 ret = -EIO;
315 goto out;
316 }
317
318 data = kmalloc(data_size, GFP_KERNEL);
319 if (!data) {
320 ret = -ENOMEM;
321 goto out;
322 }
323
324 status = efi.get_variable(name, &guid, NULL, &data_size, data);
325 if (status == EFI_SUCCESS) {
326 acpi_status acpi_ret = acpi_load_table(data, NULL);
327 if (ACPI_FAILURE(acpi_ret)) {
328 pr_err("efivar_ssdt: failed to load table: %u\n",
329 acpi_ret);
330 } else {
331 /*
332 * The @data will be in use by ACPI engine,
333 * do not free it!
334 */
335 continue;
336 }
337 } else {
338 pr_err("efivar_ssdt: failed to get var data: 0x%lx\n", status);
339 }
340 kfree(data);
341 }
342out:
343 kfree(name);
344 return ret;
345}
346#else
347static inline int efivar_ssdt_load(void) { return 0; }
348#endif
349
350#ifdef CONFIG_DEBUG_FS
351
352#define EFI_DEBUGFS_MAX_BLOBS 32
353
354static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
355
356static void __init efi_debugfs_init(void)
357{
358 struct dentry *efi_debugfs;
359 efi_memory_desc_t *md;
360 char name[32];
361 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
362 int i = 0;
363
364 efi_debugfs = debugfs_create_dir("efi", NULL);
365 if (IS_ERR(efi_debugfs))
366 return;
367
368 for_each_efi_memory_desc(md) {
369 switch (md->type) {
370 case EFI_BOOT_SERVICES_CODE:
371 snprintf(name, sizeof(name), "boot_services_code%d",
372 type_count[md->type]++);
373 break;
374 case EFI_BOOT_SERVICES_DATA:
375 snprintf(name, sizeof(name), "boot_services_data%d",
376 type_count[md->type]++);
377 break;
378 default:
379 continue;
380 }
381
382 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
383 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
384 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
385 break;
386 }
387
388 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
389 debugfs_blob[i].data = memremap(md->phys_addr,
390 debugfs_blob[i].size,
391 MEMREMAP_WB);
392 if (!debugfs_blob[i].data)
393 continue;
394
395 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
396 i++;
397 }
398}
399#else
400static inline void efi_debugfs_init(void) {}
401#endif
402
403/*
404 * We register the efi subsystem with the firmware subsystem and the
405 * efivars subsystem with the efi subsystem, if the system was booted with
406 * EFI.
407 */
408static int __init efisubsys_init(void)
409{
410 int error;
411
412 if (!efi_enabled(EFI_RUNTIME_SERVICES))
413 efi.runtime_supported_mask = 0;
414
415 if (!efi_enabled(EFI_BOOT))
416 return 0;
417
418 if (efi.runtime_supported_mask) {
419 /*
420 * Since we process only one efi_runtime_service() at a time, an
421 * ordered workqueue (which creates only one execution context)
422 * should suffice for all our needs.
423 */
424 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
425 if (!efi_rts_wq) {
426 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
427 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
428 efi.runtime_supported_mask = 0;
429 return 0;
430 }
431 }
432
433 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
434 platform_device_register_simple("rtc-efi", 0, NULL, 0);
435
436 /* We register the efi directory at /sys/firmware/efi */
437 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
438 if (!efi_kobj) {
439 pr_err("efi: Firmware registration failed.\n");
440 error = -ENOMEM;
441 goto err_destroy_wq;
442 }
443
444 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
445 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
446 error = generic_ops_register();
447 if (error)
448 goto err_put;
449 error = efivar_ssdt_load();
450 if (error)
451 pr_err("efi: failed to load SSDT, error %d.\n", error);
452 platform_device_register_simple("efivars", 0, NULL, 0);
453 }
454
455 BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh);
456
457 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
458 if (error) {
459 pr_err("efi: Sysfs attribute export failed with error %d.\n",
460 error);
461 goto err_unregister;
462 }
463
464 /* and the standard mountpoint for efivarfs */
465 error = sysfs_create_mount_point(efi_kobj, "efivars");
466 if (error) {
467 pr_err("efivars: Subsystem registration failed.\n");
468 goto err_remove_group;
469 }
470
471 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
472 efi_debugfs_init();
473
474#ifdef CONFIG_EFI_COCO_SECRET
475 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
476 platform_device_register_simple("efi_secret", 0, NULL, 0);
477#endif
478
479 return 0;
480
481err_remove_group:
482 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
483err_unregister:
484 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
485 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
486 generic_ops_unregister();
487err_put:
488 kobject_put(efi_kobj);
489 efi_kobj = NULL;
490err_destroy_wq:
491 if (efi_rts_wq)
492 destroy_workqueue(efi_rts_wq);
493
494 return error;
495}
496
497subsys_initcall(efisubsys_init);
498
499void __init efi_find_mirror(void)
500{
501 efi_memory_desc_t *md;
502 u64 mirror_size = 0, total_size = 0;
503
504 if (!efi_enabled(EFI_MEMMAP))
505 return;
506
507 for_each_efi_memory_desc(md) {
508 unsigned long long start = md->phys_addr;
509 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
510
511 total_size += size;
512 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
513 memblock_mark_mirror(start, size);
514 mirror_size += size;
515 }
516 }
517 if (mirror_size)
518 pr_info("Memory: %lldM/%lldM mirrored memory\n",
519 mirror_size>>20, total_size>>20);
520}
521
522/*
523 * Find the efi memory descriptor for a given physical address. Given a
524 * physical address, determine if it exists within an EFI Memory Map entry,
525 * and if so, populate the supplied memory descriptor with the appropriate
526 * data.
527 */
528int __efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
529{
530 efi_memory_desc_t *md;
531
532 if (!efi_enabled(EFI_MEMMAP)) {
533 pr_err_once("EFI_MEMMAP is not enabled.\n");
534 return -EINVAL;
535 }
536
537 if (!out_md) {
538 pr_err_once("out_md is null.\n");
539 return -EINVAL;
540 }
541
542 for_each_efi_memory_desc(md) {
543 u64 size;
544 u64 end;
545
546 /* skip bogus entries (including empty ones) */
547 if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
548 (md->num_pages <= 0) ||
549 (md->num_pages > (U64_MAX - md->phys_addr) >> EFI_PAGE_SHIFT))
550 continue;
551
552 size = md->num_pages << EFI_PAGE_SHIFT;
553 end = md->phys_addr + size;
554 if (phys_addr >= md->phys_addr && phys_addr < end) {
555 memcpy(out_md, md, sizeof(*out_md));
556 return 0;
557 }
558 }
559 return -ENOENT;
560}
561
562extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
563 __weak __alias(__efi_mem_desc_lookup);
564
565/*
566 * Calculate the highest address of an efi memory descriptor.
567 */
568u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
569{
570 u64 size = md->num_pages << EFI_PAGE_SHIFT;
571 u64 end = md->phys_addr + size;
572 return end;
573}
574
575void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
576
577/**
578 * efi_mem_reserve - Reserve an EFI memory region
579 * @addr: Physical address to reserve
580 * @size: Size of reservation
581 *
582 * Mark a region as reserved from general kernel allocation and
583 * prevent it being released by efi_free_boot_services().
584 *
585 * This function should be called drivers once they've parsed EFI
586 * configuration tables to figure out where their data lives, e.g.
587 * efi_esrt_init().
588 */
589void __init efi_mem_reserve(phys_addr_t addr, u64 size)
590{
591 /* efi_mem_reserve() does not work under Xen */
592 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT)))
593 return;
594
595 if (!memblock_is_region_reserved(addr, size))
596 memblock_reserve(addr, size);
597
598 /*
599 * Some architectures (x86) reserve all boot services ranges
600 * until efi_free_boot_services() because of buggy firmware
601 * implementations. This means the above memblock_reserve() is
602 * superfluous on x86 and instead what it needs to do is
603 * ensure the @start, @size is not freed.
604 */
605 efi_arch_mem_reserve(addr, size);
606}
607
608static const efi_config_table_type_t common_tables[] __initconst = {
609 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
610 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
611 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
612 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
613 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
614 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
615 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
616 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
617 {EFI_TCG2_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "TPMFinalLog" },
618 {EFI_CC_FINAL_EVENTS_TABLE_GUID, &efi.tpm_final_log, "CCFinalLog" },
619 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
620 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
621 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
622#ifdef CONFIG_EFI_RCI2_TABLE
623 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
624#endif
625#ifdef CONFIG_LOAD_UEFI_KEYS
626 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
627#endif
628#ifdef CONFIG_EFI_COCO_SECRET
629 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" },
630#endif
631#ifdef CONFIG_UNACCEPTED_MEMORY
632 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID, &efi.unaccepted, "Unaccepted" },
633#endif
634#ifdef CONFIG_EFI_GENERIC_STUB
635 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table },
636#endif
637 {},
638};
639
640static __init int match_config_table(const efi_guid_t *guid,
641 unsigned long table,
642 const efi_config_table_type_t *table_types)
643{
644 int i;
645
646 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
647 if (efi_guidcmp(*guid, table_types[i].guid))
648 continue;
649
650 if (!efi_config_table_is_usable(guid, table)) {
651 if (table_types[i].name[0])
652 pr_cont("(%s=0x%lx unusable) ",
653 table_types[i].name, table);
654 return 1;
655 }
656
657 *(table_types[i].ptr) = table;
658 if (table_types[i].name[0])
659 pr_cont("%s=0x%lx ", table_types[i].name, table);
660 return 1;
661 }
662
663 return 0;
664}
665
666/**
667 * reserve_unaccepted - Map and reserve unaccepted configuration table
668 * @unaccepted: Pointer to unaccepted memory table
669 *
670 * memblock_add() makes sure that the table is mapped in direct mapping. During
671 * normal boot it happens automatically because the table is allocated from
672 * usable memory. But during crashkernel boot only memory specifically reserved
673 * for crash scenario is mapped. memblock_add() forces the table to be mapped
674 * in crashkernel case.
675 *
676 * Align the range to the nearest page borders. Ranges smaller than page size
677 * are not going to be mapped.
678 *
679 * memblock_reserve() makes sure that future allocations will not touch the
680 * table.
681 */
682
683static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted)
684{
685 phys_addr_t start, size;
686
687 start = PAGE_ALIGN_DOWN(efi.unaccepted);
688 size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size);
689
690 memblock_add(start, size);
691 memblock_reserve(start, size);
692}
693
694int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
695 int count,
696 const efi_config_table_type_t *arch_tables)
697{
698 const efi_config_table_64_t *tbl64 = (void *)config_tables;
699 const efi_config_table_32_t *tbl32 = (void *)config_tables;
700 const efi_guid_t *guid;
701 unsigned long table;
702 int i;
703
704 pr_info("");
705 for (i = 0; i < count; i++) {
706 if (!IS_ENABLED(CONFIG_X86)) {
707 guid = &config_tables[i].guid;
708 table = (unsigned long)config_tables[i].table;
709 } else if (efi_enabled(EFI_64BIT)) {
710 guid = &tbl64[i].guid;
711 table = tbl64[i].table;
712
713 if (IS_ENABLED(CONFIG_X86_32) &&
714 tbl64[i].table > U32_MAX) {
715 pr_cont("\n");
716 pr_err("Table located above 4GB, disabling EFI.\n");
717 return -EINVAL;
718 }
719 } else {
720 guid = &tbl32[i].guid;
721 table = tbl32[i].table;
722 }
723
724 if (!match_config_table(guid, table, common_tables) && arch_tables)
725 match_config_table(guid, table, arch_tables);
726 }
727 pr_cont("\n");
728 set_bit(EFI_CONFIG_TABLES, &efi.flags);
729
730 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
731 struct linux_efi_random_seed *seed;
732 u32 size = 0;
733
734 seed = early_memremap(efi_rng_seed, sizeof(*seed));
735 if (seed != NULL) {
736 size = min_t(u32, seed->size, SZ_1K); // sanity check
737 early_memunmap(seed, sizeof(*seed));
738 } else {
739 pr_err("Could not map UEFI random seed!\n");
740 }
741 if (size > 0) {
742 seed = early_memremap(efi_rng_seed,
743 sizeof(*seed) + size);
744 if (seed != NULL) {
745 add_bootloader_randomness(seed->bits, size);
746 memzero_explicit(seed->bits, size);
747 early_memunmap(seed, sizeof(*seed) + size);
748 } else {
749 pr_err("Could not map UEFI random seed!\n");
750 }
751 }
752 }
753
754 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
755 efi_memattr_init();
756
757 efi_tpm_eventlog_init();
758
759 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
760 unsigned long prsv = mem_reserve;
761
762 while (prsv) {
763 struct linux_efi_memreserve *rsv;
764 u8 *p;
765
766 /*
767 * Just map a full page: that is what we will get
768 * anyway, and it permits us to map the entire entry
769 * before knowing its size.
770 */
771 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
772 PAGE_SIZE);
773 if (p == NULL) {
774 pr_err("Could not map UEFI memreserve entry!\n");
775 return -ENOMEM;
776 }
777
778 rsv = (void *)(p + prsv % PAGE_SIZE);
779
780 /* reserve the entry itself */
781 memblock_reserve(prsv,
782 struct_size(rsv, entry, rsv->size));
783
784 for (i = 0; i < atomic_read(&rsv->count); i++) {
785 memblock_reserve(rsv->entry[i].base,
786 rsv->entry[i].size);
787 }
788
789 prsv = rsv->next;
790 early_memunmap(p, PAGE_SIZE);
791 }
792 }
793
794 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
795 efi_rt_properties_table_t *tbl;
796
797 tbl = early_memremap(rt_prop, sizeof(*tbl));
798 if (tbl) {
799 efi.runtime_supported_mask &= tbl->runtime_services_supported;
800 early_memunmap(tbl, sizeof(*tbl));
801 }
802 }
803
804 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
805 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
806 struct linux_efi_initrd *tbl;
807
808 tbl = early_memremap(initrd, sizeof(*tbl));
809 if (tbl) {
810 phys_initrd_start = tbl->base;
811 phys_initrd_size = tbl->size;
812 early_memunmap(tbl, sizeof(*tbl));
813 }
814 }
815
816 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) &&
817 efi.unaccepted != EFI_INVALID_TABLE_ADDR) {
818 struct efi_unaccepted_memory *unaccepted;
819
820 unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted));
821 if (unaccepted) {
822
823 if (unaccepted->version == 1) {
824 reserve_unaccepted(unaccepted);
825 } else {
826 efi.unaccepted = EFI_INVALID_TABLE_ADDR;
827 }
828
829 early_memunmap(unaccepted, sizeof(*unaccepted));
830 }
831 }
832
833 return 0;
834}
835
836int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr)
837{
838 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
839 pr_err("System table signature incorrect!\n");
840 return -EINVAL;
841 }
842
843 return 0;
844}
845
846static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
847 size_t size)
848{
849 const efi_char16_t *ret;
850
851 ret = early_memremap_ro(fw_vendor, size);
852 if (!ret)
853 pr_err("Could not map the firmware vendor!\n");
854 return ret;
855}
856
857static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
858{
859 early_memunmap((void *)fw_vendor, size);
860}
861
862void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
863 unsigned long fw_vendor)
864{
865 char vendor[100] = "unknown";
866 const efi_char16_t *c16;
867 size_t i;
868 u16 rev;
869
870 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
871 if (c16) {
872 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
873 vendor[i] = c16[i];
874 vendor[i] = '\0';
875
876 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
877 }
878
879 rev = (u16)systab_hdr->revision;
880 pr_info("EFI v%u.%u", systab_hdr->revision >> 16, rev / 10);
881
882 rev %= 10;
883 if (rev)
884 pr_cont(".%u", rev);
885
886 pr_cont(" by %s\n", vendor);
887
888 if (IS_ENABLED(CONFIG_X86_64) &&
889 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
890 !strcmp(vendor, "Apple")) {
891 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
892 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
893 }
894}
895
896static __initdata char memory_type_name[][13] = {
897 "Reserved",
898 "Loader Code",
899 "Loader Data",
900 "Boot Code",
901 "Boot Data",
902 "Runtime Code",
903 "Runtime Data",
904 "Conventional",
905 "Unusable",
906 "ACPI Reclaim",
907 "ACPI Mem NVS",
908 "MMIO",
909 "MMIO Port",
910 "PAL Code",
911 "Persistent",
912 "Unaccepted",
913};
914
915char * __init efi_md_typeattr_format(char *buf, size_t size,
916 const efi_memory_desc_t *md)
917{
918 char *pos;
919 int type_len;
920 u64 attr;
921
922 pos = buf;
923 if (md->type >= ARRAY_SIZE(memory_type_name))
924 type_len = snprintf(pos, size, "[type=%u", md->type);
925 else
926 type_len = snprintf(pos, size, "[%-*s",
927 (int)(sizeof(memory_type_name[0]) - 1),
928 memory_type_name[md->type]);
929 if (type_len >= size)
930 return buf;
931
932 pos += type_len;
933 size -= type_len;
934
935 attr = md->attribute;
936 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
937 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
938 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
939 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
940 EFI_MEMORY_MORE_RELIABLE | EFI_MEMORY_HOT_PLUGGABLE |
941 EFI_MEMORY_RUNTIME))
942 snprintf(pos, size, "|attr=0x%016llx]",
943 (unsigned long long)attr);
944 else
945 snprintf(pos, size,
946 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
947 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
948 attr & EFI_MEMORY_HOT_PLUGGABLE ? "HP" : "",
949 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
950 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
951 attr & EFI_MEMORY_SP ? "SP" : "",
952 attr & EFI_MEMORY_NV ? "NV" : "",
953 attr & EFI_MEMORY_XP ? "XP" : "",
954 attr & EFI_MEMORY_RP ? "RP" : "",
955 attr & EFI_MEMORY_WP ? "WP" : "",
956 attr & EFI_MEMORY_RO ? "RO" : "",
957 attr & EFI_MEMORY_UCE ? "UCE" : "",
958 attr & EFI_MEMORY_WB ? "WB" : "",
959 attr & EFI_MEMORY_WT ? "WT" : "",
960 attr & EFI_MEMORY_WC ? "WC" : "",
961 attr & EFI_MEMORY_UC ? "UC" : "");
962 return buf;
963}
964
965/*
966 * efi_mem_attributes - lookup memmap attributes for physical address
967 * @phys_addr: the physical address to lookup
968 *
969 * Search in the EFI memory map for the region covering
970 * @phys_addr. Returns the EFI memory attributes if the region
971 * was found in the memory map, 0 otherwise.
972 */
973u64 efi_mem_attributes(unsigned long phys_addr)
974{
975 efi_memory_desc_t *md;
976
977 if (!efi_enabled(EFI_MEMMAP))
978 return 0;
979
980 for_each_efi_memory_desc(md) {
981 if ((md->phys_addr <= phys_addr) &&
982 (phys_addr < (md->phys_addr +
983 (md->num_pages << EFI_PAGE_SHIFT))))
984 return md->attribute;
985 }
986 return 0;
987}
988
989/*
990 * efi_mem_type - lookup memmap type for physical address
991 * @phys_addr: the physical address to lookup
992 *
993 * Search in the EFI memory map for the region covering @phys_addr.
994 * Returns the EFI memory type if the region was found in the memory
995 * map, -EINVAL otherwise.
996 */
997int efi_mem_type(unsigned long phys_addr)
998{
999 const efi_memory_desc_t *md;
1000
1001 if (!efi_enabled(EFI_MEMMAP))
1002 return -ENOTSUPP;
1003
1004 for_each_efi_memory_desc(md) {
1005 if ((md->phys_addr <= phys_addr) &&
1006 (phys_addr < (md->phys_addr +
1007 (md->num_pages << EFI_PAGE_SHIFT))))
1008 return md->type;
1009 }
1010 return -EINVAL;
1011}
1012
1013int efi_status_to_err(efi_status_t status)
1014{
1015 int err;
1016
1017 switch (status) {
1018 case EFI_SUCCESS:
1019 err = 0;
1020 break;
1021 case EFI_INVALID_PARAMETER:
1022 err = -EINVAL;
1023 break;
1024 case EFI_OUT_OF_RESOURCES:
1025 err = -ENOSPC;
1026 break;
1027 case EFI_DEVICE_ERROR:
1028 err = -EIO;
1029 break;
1030 case EFI_WRITE_PROTECTED:
1031 err = -EROFS;
1032 break;
1033 case EFI_SECURITY_VIOLATION:
1034 err = -EACCES;
1035 break;
1036 case EFI_NOT_FOUND:
1037 err = -ENOENT;
1038 break;
1039 case EFI_ABORTED:
1040 err = -EINTR;
1041 break;
1042 default:
1043 err = -EINVAL;
1044 }
1045
1046 return err;
1047}
1048EXPORT_SYMBOL_GPL(efi_status_to_err);
1049
1050static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
1051static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
1052
1053static int __init efi_memreserve_map_root(void)
1054{
1055 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
1056 return -ENODEV;
1057
1058 efi_memreserve_root = memremap(mem_reserve,
1059 sizeof(*efi_memreserve_root),
1060 MEMREMAP_WB);
1061 if (WARN_ON_ONCE(!efi_memreserve_root))
1062 return -ENOMEM;
1063 return 0;
1064}
1065
1066static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
1067{
1068 struct resource *res, *parent;
1069 int ret;
1070
1071 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
1072 if (!res)
1073 return -ENOMEM;
1074
1075 res->name = "reserved";
1076 res->flags = IORESOURCE_MEM;
1077 res->start = addr;
1078 res->end = addr + size - 1;
1079
1080 /* we expect a conflict with a 'System RAM' region */
1081 parent = request_resource_conflict(&iomem_resource, res);
1082 ret = parent ? request_resource(parent, res) : 0;
1083
1084 /*
1085 * Given that efi_mem_reserve_iomem() can be called at any
1086 * time, only call memblock_reserve() if the architecture
1087 * keeps the infrastructure around.
1088 */
1089 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
1090 memblock_reserve(addr, size);
1091
1092 return ret;
1093}
1094
1095int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
1096{
1097 struct linux_efi_memreserve *rsv;
1098 unsigned long prsv;
1099 int rc, index;
1100
1101 if (efi_memreserve_root == (void *)ULONG_MAX)
1102 return -ENODEV;
1103
1104 if (!efi_memreserve_root) {
1105 rc = efi_memreserve_map_root();
1106 if (rc)
1107 return rc;
1108 }
1109
1110 /* first try to find a slot in an existing linked list entry */
1111 for (prsv = efi_memreserve_root->next; prsv; ) {
1112 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1113 if (!rsv)
1114 return -ENOMEM;
1115 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1116 if (index < rsv->size) {
1117 rsv->entry[index].base = addr;
1118 rsv->entry[index].size = size;
1119
1120 memunmap(rsv);
1121 return efi_mem_reserve_iomem(addr, size);
1122 }
1123 prsv = rsv->next;
1124 memunmap(rsv);
1125 }
1126
1127 /* no slot found - allocate a new linked list entry */
1128 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1129 if (!rsv)
1130 return -ENOMEM;
1131
1132 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1133 if (rc) {
1134 free_page((unsigned long)rsv);
1135 return rc;
1136 }
1137
1138 /*
1139 * The memremap() call above assumes that a linux_efi_memreserve entry
1140 * never crosses a page boundary, so let's ensure that this remains true
1141 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1142 * using SZ_4K explicitly in the size calculation below.
1143 */
1144 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1145 atomic_set(&rsv->count, 1);
1146 rsv->entry[0].base = addr;
1147 rsv->entry[0].size = size;
1148
1149 spin_lock(&efi_mem_reserve_persistent_lock);
1150 rsv->next = efi_memreserve_root->next;
1151 efi_memreserve_root->next = __pa(rsv);
1152 spin_unlock(&efi_mem_reserve_persistent_lock);
1153
1154 return efi_mem_reserve_iomem(addr, size);
1155}
1156
1157static int __init efi_memreserve_root_init(void)
1158{
1159 if (efi_memreserve_root)
1160 return 0;
1161 if (efi_memreserve_map_root())
1162 efi_memreserve_root = (void *)ULONG_MAX;
1163 return 0;
1164}
1165early_initcall(efi_memreserve_root_init);
1166
1167#ifdef CONFIG_KEXEC
1168static int update_efi_random_seed(struct notifier_block *nb,
1169 unsigned long code, void *unused)
1170{
1171 struct linux_efi_random_seed *seed;
1172 u32 size = 0;
1173
1174 if (!kexec_in_progress)
1175 return NOTIFY_DONE;
1176
1177 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1178 if (seed != NULL) {
1179 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1180 memunmap(seed);
1181 } else {
1182 pr_err("Could not map UEFI random seed!\n");
1183 }
1184 if (size > 0) {
1185 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1186 MEMREMAP_WB);
1187 if (seed != NULL) {
1188 seed->size = size;
1189 get_random_bytes(seed->bits, seed->size);
1190 memunmap(seed);
1191 } else {
1192 pr_err("Could not map UEFI random seed!\n");
1193 }
1194 }
1195 return NOTIFY_DONE;
1196}
1197
1198static struct notifier_block efi_random_seed_nb = {
1199 .notifier_call = update_efi_random_seed,
1200};
1201
1202static int __init register_update_efi_random_seed(void)
1203{
1204 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1205 return 0;
1206 return register_reboot_notifier(&efi_random_seed_nb);
1207}
1208late_initcall(register_update_efi_random_seed);
1209#endif