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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/io.h>
25#include <linux/kexec.h>
26#include <linux/platform_device.h>
27#include <linux/random.h>
28#include <linux/reboot.h>
29#include <linux/slab.h>
30#include <linux/acpi.h>
31#include <linux/ucs2_string.h>
32#include <linux/memblock.h>
33#include <linux/security.h>
34
35#include <asm/early_ioremap.h>
36
37struct efi __read_mostly efi = {
38 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
39 .acpi = EFI_INVALID_TABLE_ADDR,
40 .acpi20 = EFI_INVALID_TABLE_ADDR,
41 .smbios = EFI_INVALID_TABLE_ADDR,
42 .smbios3 = EFI_INVALID_TABLE_ADDR,
43 .esrt = EFI_INVALID_TABLE_ADDR,
44 .tpm_log = EFI_INVALID_TABLE_ADDR,
45 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
46};
47EXPORT_SYMBOL(efi);
48
49unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
50static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
51static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
52
53struct mm_struct efi_mm = {
54 .mm_rb = RB_ROOT,
55 .mm_users = ATOMIC_INIT(2),
56 .mm_count = ATOMIC_INIT(1),
57 MMAP_LOCK_INITIALIZER(efi_mm)
58 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
59 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
60 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
61};
62
63struct workqueue_struct *efi_rts_wq;
64
65static bool disable_runtime;
66static int __init setup_noefi(char *arg)
67{
68 disable_runtime = true;
69 return 0;
70}
71early_param("noefi", setup_noefi);
72
73bool efi_runtime_disabled(void)
74{
75 return disable_runtime;
76}
77
78bool __pure __efi_soft_reserve_enabled(void)
79{
80 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
81}
82
83static int __init parse_efi_cmdline(char *str)
84{
85 if (!str) {
86 pr_warn("need at least one option\n");
87 return -EINVAL;
88 }
89
90 if (parse_option_str(str, "debug"))
91 set_bit(EFI_DBG, &efi.flags);
92
93 if (parse_option_str(str, "noruntime"))
94 disable_runtime = true;
95
96 if (parse_option_str(str, "nosoftreserve"))
97 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
98
99 return 0;
100}
101early_param("efi", parse_efi_cmdline);
102
103struct kobject *efi_kobj;
104
105/*
106 * Let's not leave out systab information that snuck into
107 * the efivars driver
108 * Note, do not add more fields in systab sysfs file as it breaks sysfs
109 * one value per file rule!
110 */
111static ssize_t systab_show(struct kobject *kobj,
112 struct kobj_attribute *attr, char *buf)
113{
114 char *str = buf;
115
116 if (!kobj || !buf)
117 return -EINVAL;
118
119 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
120 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
121 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
122 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
123 /*
124 * If both SMBIOS and SMBIOS3 entry points are implemented, the
125 * SMBIOS3 entry point shall be preferred, so we list it first to
126 * let applications stop parsing after the first match.
127 */
128 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
129 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
130 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
131 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
132
133 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
134 str = efi_systab_show_arch(str);
135
136 return str - buf;
137}
138
139static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
140
141static ssize_t fw_platform_size_show(struct kobject *kobj,
142 struct kobj_attribute *attr, char *buf)
143{
144 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
145}
146
147extern __weak struct kobj_attribute efi_attr_fw_vendor;
148extern __weak struct kobj_attribute efi_attr_runtime;
149extern __weak struct kobj_attribute efi_attr_config_table;
150static struct kobj_attribute efi_attr_fw_platform_size =
151 __ATTR_RO(fw_platform_size);
152
153static struct attribute *efi_subsys_attrs[] = {
154 &efi_attr_systab.attr,
155 &efi_attr_fw_platform_size.attr,
156 &efi_attr_fw_vendor.attr,
157 &efi_attr_runtime.attr,
158 &efi_attr_config_table.attr,
159 NULL,
160};
161
162umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
163 int n)
164{
165 return attr->mode;
166}
167
168static const struct attribute_group efi_subsys_attr_group = {
169 .attrs = efi_subsys_attrs,
170 .is_visible = efi_attr_is_visible,
171};
172
173static struct efivars generic_efivars;
174static struct efivar_operations generic_ops;
175
176static int generic_ops_register(void)
177{
178 generic_ops.get_variable = efi.get_variable;
179 generic_ops.get_next_variable = efi.get_next_variable;
180 generic_ops.query_variable_store = efi_query_variable_store;
181
182 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
183 generic_ops.set_variable = efi.set_variable;
184 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
185 }
186 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
187}
188
189static void generic_ops_unregister(void)
190{
191 efivars_unregister(&generic_efivars);
192}
193
194#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
195#define EFIVAR_SSDT_NAME_MAX 16
196static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
197static int __init efivar_ssdt_setup(char *str)
198{
199 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
200
201 if (ret)
202 return ret;
203
204 if (strlen(str) < sizeof(efivar_ssdt))
205 memcpy(efivar_ssdt, str, strlen(str));
206 else
207 pr_warn("efivar_ssdt: name too long: %s\n", str);
208 return 0;
209}
210__setup("efivar_ssdt=", efivar_ssdt_setup);
211
212static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
213 unsigned long name_size, void *data)
214{
215 struct efivar_entry *entry;
216 struct list_head *list = data;
217 char utf8_name[EFIVAR_SSDT_NAME_MAX];
218 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
219
220 ucs2_as_utf8(utf8_name, name, limit - 1);
221 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
222 return 0;
223
224 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
225 if (!entry)
226 return 0;
227
228 memcpy(entry->var.VariableName, name, name_size);
229 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
230
231 efivar_entry_add(entry, list);
232
233 return 0;
234}
235
236static __init int efivar_ssdt_load(void)
237{
238 LIST_HEAD(entries);
239 struct efivar_entry *entry, *aux;
240 unsigned long size;
241 void *data;
242 int ret;
243
244 if (!efivar_ssdt[0])
245 return 0;
246
247 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
248
249 list_for_each_entry_safe(entry, aux, &entries, list) {
250 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
251 &entry->var.VendorGuid);
252
253 list_del(&entry->list);
254
255 ret = efivar_entry_size(entry, &size);
256 if (ret) {
257 pr_err("failed to get var size\n");
258 goto free_entry;
259 }
260
261 data = kmalloc(size, GFP_KERNEL);
262 if (!data) {
263 ret = -ENOMEM;
264 goto free_entry;
265 }
266
267 ret = efivar_entry_get(entry, NULL, &size, data);
268 if (ret) {
269 pr_err("failed to get var data\n");
270 goto free_data;
271 }
272
273 ret = acpi_load_table(data, NULL);
274 if (ret) {
275 pr_err("failed to load table: %d\n", ret);
276 goto free_data;
277 }
278
279 goto free_entry;
280
281free_data:
282 kfree(data);
283
284free_entry:
285 kfree(entry);
286 }
287
288 return ret;
289}
290#else
291static inline int efivar_ssdt_load(void) { return 0; }
292#endif
293
294#ifdef CONFIG_DEBUG_FS
295
296#define EFI_DEBUGFS_MAX_BLOBS 32
297
298static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
299
300static void __init efi_debugfs_init(void)
301{
302 struct dentry *efi_debugfs;
303 efi_memory_desc_t *md;
304 char name[32];
305 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
306 int i = 0;
307
308 efi_debugfs = debugfs_create_dir("efi", NULL);
309 if (IS_ERR_OR_NULL(efi_debugfs))
310 return;
311
312 for_each_efi_memory_desc(md) {
313 switch (md->type) {
314 case EFI_BOOT_SERVICES_CODE:
315 snprintf(name, sizeof(name), "boot_services_code%d",
316 type_count[md->type]++);
317 break;
318 case EFI_BOOT_SERVICES_DATA:
319 snprintf(name, sizeof(name), "boot_services_data%d",
320 type_count[md->type]++);
321 break;
322 default:
323 continue;
324 }
325
326 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
327 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
328 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
329 break;
330 }
331
332 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
333 debugfs_blob[i].data = memremap(md->phys_addr,
334 debugfs_blob[i].size,
335 MEMREMAP_WB);
336 if (!debugfs_blob[i].data)
337 continue;
338
339 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
340 i++;
341 }
342}
343#else
344static inline void efi_debugfs_init(void) {}
345#endif
346
347/*
348 * We register the efi subsystem with the firmware subsystem and the
349 * efivars subsystem with the efi subsystem, if the system was booted with
350 * EFI.
351 */
352static int __init efisubsys_init(void)
353{
354 int error;
355
356 if (!efi_enabled(EFI_RUNTIME_SERVICES))
357 efi.runtime_supported_mask = 0;
358
359 if (!efi_enabled(EFI_BOOT))
360 return 0;
361
362 if (efi.runtime_supported_mask) {
363 /*
364 * Since we process only one efi_runtime_service() at a time, an
365 * ordered workqueue (which creates only one execution context)
366 * should suffice for all our needs.
367 */
368 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
369 if (!efi_rts_wq) {
370 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
371 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
372 efi.runtime_supported_mask = 0;
373 return 0;
374 }
375 }
376
377 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
378 platform_device_register_simple("rtc-efi", 0, NULL, 0);
379
380 /* We register the efi directory at /sys/firmware/efi */
381 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
382 if (!efi_kobj) {
383 pr_err("efi: Firmware registration failed.\n");
384 destroy_workqueue(efi_rts_wq);
385 return -ENOMEM;
386 }
387
388 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
389 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
390 efivar_ssdt_load();
391 error = generic_ops_register();
392 if (error)
393 goto err_put;
394 platform_device_register_simple("efivars", 0, NULL, 0);
395 }
396
397 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
398 if (error) {
399 pr_err("efi: Sysfs attribute export failed with error %d.\n",
400 error);
401 goto err_unregister;
402 }
403
404 error = efi_runtime_map_init(efi_kobj);
405 if (error)
406 goto err_remove_group;
407
408 /* and the standard mountpoint for efivarfs */
409 error = sysfs_create_mount_point(efi_kobj, "efivars");
410 if (error) {
411 pr_err("efivars: Subsystem registration failed.\n");
412 goto err_remove_group;
413 }
414
415 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
416 efi_debugfs_init();
417
418 return 0;
419
420err_remove_group:
421 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
422err_unregister:
423 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
424 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
425 generic_ops_unregister();
426err_put:
427 kobject_put(efi_kobj);
428 destroy_workqueue(efi_rts_wq);
429 return error;
430}
431
432subsys_initcall(efisubsys_init);
433
434/*
435 * Find the efi memory descriptor for a given physical address. Given a
436 * physical address, determine if it exists within an EFI Memory Map entry,
437 * and if so, populate the supplied memory descriptor with the appropriate
438 * data.
439 */
440int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
441{
442 efi_memory_desc_t *md;
443
444 if (!efi_enabled(EFI_MEMMAP)) {
445 pr_err_once("EFI_MEMMAP is not enabled.\n");
446 return -EINVAL;
447 }
448
449 if (!out_md) {
450 pr_err_once("out_md is null.\n");
451 return -EINVAL;
452 }
453
454 for_each_efi_memory_desc(md) {
455 u64 size;
456 u64 end;
457
458 size = md->num_pages << EFI_PAGE_SHIFT;
459 end = md->phys_addr + size;
460 if (phys_addr >= md->phys_addr && phys_addr < end) {
461 memcpy(out_md, md, sizeof(*out_md));
462 return 0;
463 }
464 }
465 return -ENOENT;
466}
467
468/*
469 * Calculate the highest address of an efi memory descriptor.
470 */
471u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
472{
473 u64 size = md->num_pages << EFI_PAGE_SHIFT;
474 u64 end = md->phys_addr + size;
475 return end;
476}
477
478void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
479
480/**
481 * efi_mem_reserve - Reserve an EFI memory region
482 * @addr: Physical address to reserve
483 * @size: Size of reservation
484 *
485 * Mark a region as reserved from general kernel allocation and
486 * prevent it being released by efi_free_boot_services().
487 *
488 * This function should be called drivers once they've parsed EFI
489 * configuration tables to figure out where their data lives, e.g.
490 * efi_esrt_init().
491 */
492void __init efi_mem_reserve(phys_addr_t addr, u64 size)
493{
494 if (!memblock_is_region_reserved(addr, size))
495 memblock_reserve(addr, size);
496
497 /*
498 * Some architectures (x86) reserve all boot services ranges
499 * until efi_free_boot_services() because of buggy firmware
500 * implementations. This means the above memblock_reserve() is
501 * superfluous on x86 and instead what it needs to do is
502 * ensure the @start, @size is not freed.
503 */
504 efi_arch_mem_reserve(addr, size);
505}
506
507static const efi_config_table_type_t common_tables[] __initconst = {
508 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
509 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
510 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
511 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
512 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
513 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
514 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
515 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
516 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" },
517 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
518 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
519#ifdef CONFIG_EFI_RCI2_TABLE
520 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
521#endif
522 {},
523};
524
525static __init int match_config_table(const efi_guid_t *guid,
526 unsigned long table,
527 const efi_config_table_type_t *table_types)
528{
529 int i;
530
531 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
532 if (!efi_guidcmp(*guid, table_types[i].guid)) {
533 *(table_types[i].ptr) = table;
534 if (table_types[i].name[0])
535 pr_cont("%s=0x%lx ",
536 table_types[i].name, table);
537 return 1;
538 }
539 }
540
541 return 0;
542}
543
544int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
545 int count,
546 const efi_config_table_type_t *arch_tables)
547{
548 const efi_config_table_64_t *tbl64 = (void *)config_tables;
549 const efi_config_table_32_t *tbl32 = (void *)config_tables;
550 const efi_guid_t *guid;
551 unsigned long table;
552 int i;
553
554 pr_info("");
555 for (i = 0; i < count; i++) {
556 if (!IS_ENABLED(CONFIG_X86)) {
557 guid = &config_tables[i].guid;
558 table = (unsigned long)config_tables[i].table;
559 } else if (efi_enabled(EFI_64BIT)) {
560 guid = &tbl64[i].guid;
561 table = tbl64[i].table;
562
563 if (IS_ENABLED(CONFIG_X86_32) &&
564 tbl64[i].table > U32_MAX) {
565 pr_cont("\n");
566 pr_err("Table located above 4GB, disabling EFI.\n");
567 return -EINVAL;
568 }
569 } else {
570 guid = &tbl32[i].guid;
571 table = tbl32[i].table;
572 }
573
574 if (!match_config_table(guid, table, common_tables) && arch_tables)
575 match_config_table(guid, table, arch_tables);
576 }
577 pr_cont("\n");
578 set_bit(EFI_CONFIG_TABLES, &efi.flags);
579
580 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
581 struct linux_efi_random_seed *seed;
582 u32 size = 0;
583
584 seed = early_memremap(efi_rng_seed, sizeof(*seed));
585 if (seed != NULL) {
586 size = READ_ONCE(seed->size);
587 early_memunmap(seed, sizeof(*seed));
588 } else {
589 pr_err("Could not map UEFI random seed!\n");
590 }
591 if (size > 0) {
592 seed = early_memremap(efi_rng_seed,
593 sizeof(*seed) + size);
594 if (seed != NULL) {
595 pr_notice("seeding entropy pool\n");
596 add_bootloader_randomness(seed->bits, size);
597 early_memunmap(seed, sizeof(*seed) + size);
598 } else {
599 pr_err("Could not map UEFI random seed!\n");
600 }
601 }
602 }
603
604 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
605 efi_memattr_init();
606
607 efi_tpm_eventlog_init();
608
609 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
610 unsigned long prsv = mem_reserve;
611
612 while (prsv) {
613 struct linux_efi_memreserve *rsv;
614 u8 *p;
615
616 /*
617 * Just map a full page: that is what we will get
618 * anyway, and it permits us to map the entire entry
619 * before knowing its size.
620 */
621 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
622 PAGE_SIZE);
623 if (p == NULL) {
624 pr_err("Could not map UEFI memreserve entry!\n");
625 return -ENOMEM;
626 }
627
628 rsv = (void *)(p + prsv % PAGE_SIZE);
629
630 /* reserve the entry itself */
631 memblock_reserve(prsv,
632 struct_size(rsv, entry, rsv->size));
633
634 for (i = 0; i < atomic_read(&rsv->count); i++) {
635 memblock_reserve(rsv->entry[i].base,
636 rsv->entry[i].size);
637 }
638
639 prsv = rsv->next;
640 early_memunmap(p, PAGE_SIZE);
641 }
642 }
643
644 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
645 efi_rt_properties_table_t *tbl;
646
647 tbl = early_memremap(rt_prop, sizeof(*tbl));
648 if (tbl) {
649 efi.runtime_supported_mask &= tbl->runtime_services_supported;
650 early_memunmap(tbl, sizeof(*tbl));
651 }
652 }
653
654 return 0;
655}
656
657int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr,
658 int min_major_version)
659{
660 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
661 pr_err("System table signature incorrect!\n");
662 return -EINVAL;
663 }
664
665 if ((systab_hdr->revision >> 16) < min_major_version)
666 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n",
667 systab_hdr->revision >> 16,
668 systab_hdr->revision & 0xffff,
669 min_major_version);
670
671 return 0;
672}
673
674#ifndef CONFIG_IA64
675static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
676 size_t size)
677{
678 const efi_char16_t *ret;
679
680 ret = early_memremap_ro(fw_vendor, size);
681 if (!ret)
682 pr_err("Could not map the firmware vendor!\n");
683 return ret;
684}
685
686static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
687{
688 early_memunmap((void *)fw_vendor, size);
689}
690#else
691#define map_fw_vendor(p, s) __va(p)
692#define unmap_fw_vendor(v, s)
693#endif
694
695void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
696 unsigned long fw_vendor)
697{
698 char vendor[100] = "unknown";
699 const efi_char16_t *c16;
700 size_t i;
701
702 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
703 if (c16) {
704 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
705 vendor[i] = c16[i];
706 vendor[i] = '\0';
707
708 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
709 }
710
711 pr_info("EFI v%u.%.02u by %s\n",
712 systab_hdr->revision >> 16,
713 systab_hdr->revision & 0xffff,
714 vendor);
715}
716
717static __initdata char memory_type_name[][20] = {
718 "Reserved",
719 "Loader Code",
720 "Loader Data",
721 "Boot Code",
722 "Boot Data",
723 "Runtime Code",
724 "Runtime Data",
725 "Conventional Memory",
726 "Unusable Memory",
727 "ACPI Reclaim Memory",
728 "ACPI Memory NVS",
729 "Memory Mapped I/O",
730 "MMIO Port Space",
731 "PAL Code",
732 "Persistent Memory",
733};
734
735char * __init efi_md_typeattr_format(char *buf, size_t size,
736 const efi_memory_desc_t *md)
737{
738 char *pos;
739 int type_len;
740 u64 attr;
741
742 pos = buf;
743 if (md->type >= ARRAY_SIZE(memory_type_name))
744 type_len = snprintf(pos, size, "[type=%u", md->type);
745 else
746 type_len = snprintf(pos, size, "[%-*s",
747 (int)(sizeof(memory_type_name[0]) - 1),
748 memory_type_name[md->type]);
749 if (type_len >= size)
750 return buf;
751
752 pos += type_len;
753 size -= type_len;
754
755 attr = md->attribute;
756 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
757 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
758 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
759 EFI_MEMORY_NV | EFI_MEMORY_SP |
760 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
761 snprintf(pos, size, "|attr=0x%016llx]",
762 (unsigned long long)attr);
763 else
764 snprintf(pos, size,
765 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
766 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
767 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
768 attr & EFI_MEMORY_SP ? "SP" : "",
769 attr & EFI_MEMORY_NV ? "NV" : "",
770 attr & EFI_MEMORY_XP ? "XP" : "",
771 attr & EFI_MEMORY_RP ? "RP" : "",
772 attr & EFI_MEMORY_WP ? "WP" : "",
773 attr & EFI_MEMORY_RO ? "RO" : "",
774 attr & EFI_MEMORY_UCE ? "UCE" : "",
775 attr & EFI_MEMORY_WB ? "WB" : "",
776 attr & EFI_MEMORY_WT ? "WT" : "",
777 attr & EFI_MEMORY_WC ? "WC" : "",
778 attr & EFI_MEMORY_UC ? "UC" : "");
779 return buf;
780}
781
782/*
783 * IA64 has a funky EFI memory map that doesn't work the same way as
784 * other architectures.
785 */
786#ifndef CONFIG_IA64
787/*
788 * efi_mem_attributes - lookup memmap attributes for physical address
789 * @phys_addr: the physical address to lookup
790 *
791 * Search in the EFI memory map for the region covering
792 * @phys_addr. Returns the EFI memory attributes if the region
793 * was found in the memory map, 0 otherwise.
794 */
795u64 efi_mem_attributes(unsigned long phys_addr)
796{
797 efi_memory_desc_t *md;
798
799 if (!efi_enabled(EFI_MEMMAP))
800 return 0;
801
802 for_each_efi_memory_desc(md) {
803 if ((md->phys_addr <= phys_addr) &&
804 (phys_addr < (md->phys_addr +
805 (md->num_pages << EFI_PAGE_SHIFT))))
806 return md->attribute;
807 }
808 return 0;
809}
810
811/*
812 * efi_mem_type - lookup memmap type for physical address
813 * @phys_addr: the physical address to lookup
814 *
815 * Search in the EFI memory map for the region covering @phys_addr.
816 * Returns the EFI memory type if the region was found in the memory
817 * map, -EINVAL otherwise.
818 */
819int efi_mem_type(unsigned long phys_addr)
820{
821 const efi_memory_desc_t *md;
822
823 if (!efi_enabled(EFI_MEMMAP))
824 return -ENOTSUPP;
825
826 for_each_efi_memory_desc(md) {
827 if ((md->phys_addr <= phys_addr) &&
828 (phys_addr < (md->phys_addr +
829 (md->num_pages << EFI_PAGE_SHIFT))))
830 return md->type;
831 }
832 return -EINVAL;
833}
834#endif
835
836int efi_status_to_err(efi_status_t status)
837{
838 int err;
839
840 switch (status) {
841 case EFI_SUCCESS:
842 err = 0;
843 break;
844 case EFI_INVALID_PARAMETER:
845 err = -EINVAL;
846 break;
847 case EFI_OUT_OF_RESOURCES:
848 err = -ENOSPC;
849 break;
850 case EFI_DEVICE_ERROR:
851 err = -EIO;
852 break;
853 case EFI_WRITE_PROTECTED:
854 err = -EROFS;
855 break;
856 case EFI_SECURITY_VIOLATION:
857 err = -EACCES;
858 break;
859 case EFI_NOT_FOUND:
860 err = -ENOENT;
861 break;
862 case EFI_ABORTED:
863 err = -EINTR;
864 break;
865 default:
866 err = -EINVAL;
867 }
868
869 return err;
870}
871
872static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
873static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
874
875static int __init efi_memreserve_map_root(void)
876{
877 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
878 return -ENODEV;
879
880 efi_memreserve_root = memremap(mem_reserve,
881 sizeof(*efi_memreserve_root),
882 MEMREMAP_WB);
883 if (WARN_ON_ONCE(!efi_memreserve_root))
884 return -ENOMEM;
885 return 0;
886}
887
888static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
889{
890 struct resource *res, *parent;
891
892 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
893 if (!res)
894 return -ENOMEM;
895
896 res->name = "reserved";
897 res->flags = IORESOURCE_MEM;
898 res->start = addr;
899 res->end = addr + size - 1;
900
901 /* we expect a conflict with a 'System RAM' region */
902 parent = request_resource_conflict(&iomem_resource, res);
903 return parent ? request_resource(parent, res) : 0;
904}
905
906int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
907{
908 struct linux_efi_memreserve *rsv;
909 unsigned long prsv;
910 int rc, index;
911
912 if (efi_memreserve_root == (void *)ULONG_MAX)
913 return -ENODEV;
914
915 if (!efi_memreserve_root) {
916 rc = efi_memreserve_map_root();
917 if (rc)
918 return rc;
919 }
920
921 /* first try to find a slot in an existing linked list entry */
922 for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) {
923 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
924 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
925 if (index < rsv->size) {
926 rsv->entry[index].base = addr;
927 rsv->entry[index].size = size;
928
929 memunmap(rsv);
930 return efi_mem_reserve_iomem(addr, size);
931 }
932 memunmap(rsv);
933 }
934
935 /* no slot found - allocate a new linked list entry */
936 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
937 if (!rsv)
938 return -ENOMEM;
939
940 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
941 if (rc) {
942 free_page((unsigned long)rsv);
943 return rc;
944 }
945
946 /*
947 * The memremap() call above assumes that a linux_efi_memreserve entry
948 * never crosses a page boundary, so let's ensure that this remains true
949 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
950 * using SZ_4K explicitly in the size calculation below.
951 */
952 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
953 atomic_set(&rsv->count, 1);
954 rsv->entry[0].base = addr;
955 rsv->entry[0].size = size;
956
957 spin_lock(&efi_mem_reserve_persistent_lock);
958 rsv->next = efi_memreserve_root->next;
959 efi_memreserve_root->next = __pa(rsv);
960 spin_unlock(&efi_mem_reserve_persistent_lock);
961
962 return efi_mem_reserve_iomem(addr, size);
963}
964
965static int __init efi_memreserve_root_init(void)
966{
967 if (efi_memreserve_root)
968 return 0;
969 if (efi_memreserve_map_root())
970 efi_memreserve_root = (void *)ULONG_MAX;
971 return 0;
972}
973early_initcall(efi_memreserve_root_init);
974
975#ifdef CONFIG_KEXEC
976static int update_efi_random_seed(struct notifier_block *nb,
977 unsigned long code, void *unused)
978{
979 struct linux_efi_random_seed *seed;
980 u32 size = 0;
981
982 if (!kexec_in_progress)
983 return NOTIFY_DONE;
984
985 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
986 if (seed != NULL) {
987 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
988 memunmap(seed);
989 } else {
990 pr_err("Could not map UEFI random seed!\n");
991 }
992 if (size > 0) {
993 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
994 MEMREMAP_WB);
995 if (seed != NULL) {
996 seed->size = size;
997 get_random_bytes(seed->bits, seed->size);
998 memunmap(seed);
999 } else {
1000 pr_err("Could not map UEFI random seed!\n");
1001 }
1002 }
1003 return NOTIFY_DONE;
1004}
1005
1006static struct notifier_block efi_random_seed_nb = {
1007 .notifier_call = update_efi_random_seed,
1008};
1009
1010static int __init register_update_efi_random_seed(void)
1011{
1012 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1013 return 0;
1014 return register_reboot_notifier(&efi_random_seed_nb);
1015}
1016late_initcall(register_update_efi_random_seed);
1017#endif
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * efi.c - EFI subsystem
4 *
5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 *
9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
10 * allowing the efivarfs to be mounted or the efivars module to be loaded.
11 * The existance of /sys/firmware/efi may also be used by userspace to
12 * determine that the system supports EFI.
13 */
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <linux/kobject.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/debugfs.h>
21#include <linux/device.h>
22#include <linux/efi.h>
23#include <linux/of.h>
24#include <linux/io.h>
25#include <linux/kexec.h>
26#include <linux/platform_device.h>
27#include <linux/random.h>
28#include <linux/reboot.h>
29#include <linux/slab.h>
30#include <linux/acpi.h>
31#include <linux/ucs2_string.h>
32#include <linux/memblock.h>
33#include <linux/security.h>
34
35#include <asm/early_ioremap.h>
36
37struct efi __read_mostly efi = {
38 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
39 .acpi = EFI_INVALID_TABLE_ADDR,
40 .acpi20 = EFI_INVALID_TABLE_ADDR,
41 .smbios = EFI_INVALID_TABLE_ADDR,
42 .smbios3 = EFI_INVALID_TABLE_ADDR,
43 .esrt = EFI_INVALID_TABLE_ADDR,
44 .tpm_log = EFI_INVALID_TABLE_ADDR,
45 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
46#ifdef CONFIG_LOAD_UEFI_KEYS
47 .mokvar_table = EFI_INVALID_TABLE_ADDR,
48#endif
49};
50EXPORT_SYMBOL(efi);
51
52unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
53static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
54static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
55
56struct mm_struct efi_mm = {
57 .mm_rb = RB_ROOT,
58 .mm_users = ATOMIC_INIT(2),
59 .mm_count = ATOMIC_INIT(1),
60 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
61 MMAP_LOCK_INITIALIZER(efi_mm)
62 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
63 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
64 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
65};
66
67struct workqueue_struct *efi_rts_wq;
68
69static bool disable_runtime;
70static int __init setup_noefi(char *arg)
71{
72 disable_runtime = true;
73 return 0;
74}
75early_param("noefi", setup_noefi);
76
77bool efi_runtime_disabled(void)
78{
79 return disable_runtime;
80}
81
82bool __pure __efi_soft_reserve_enabled(void)
83{
84 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
85}
86
87static int __init parse_efi_cmdline(char *str)
88{
89 if (!str) {
90 pr_warn("need at least one option\n");
91 return -EINVAL;
92 }
93
94 if (parse_option_str(str, "debug"))
95 set_bit(EFI_DBG, &efi.flags);
96
97 if (parse_option_str(str, "noruntime"))
98 disable_runtime = true;
99
100 if (parse_option_str(str, "nosoftreserve"))
101 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
102
103 return 0;
104}
105early_param("efi", parse_efi_cmdline);
106
107struct kobject *efi_kobj;
108
109/*
110 * Let's not leave out systab information that snuck into
111 * the efivars driver
112 * Note, do not add more fields in systab sysfs file as it breaks sysfs
113 * one value per file rule!
114 */
115static ssize_t systab_show(struct kobject *kobj,
116 struct kobj_attribute *attr, char *buf)
117{
118 char *str = buf;
119
120 if (!kobj || !buf)
121 return -EINVAL;
122
123 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
124 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
125 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
126 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
127 /*
128 * If both SMBIOS and SMBIOS3 entry points are implemented, the
129 * SMBIOS3 entry point shall be preferred, so we list it first to
130 * let applications stop parsing after the first match.
131 */
132 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
133 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
134 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
135 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
136
137 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
138 str = efi_systab_show_arch(str);
139
140 return str - buf;
141}
142
143static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
144
145static ssize_t fw_platform_size_show(struct kobject *kobj,
146 struct kobj_attribute *attr, char *buf)
147{
148 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
149}
150
151extern __weak struct kobj_attribute efi_attr_fw_vendor;
152extern __weak struct kobj_attribute efi_attr_runtime;
153extern __weak struct kobj_attribute efi_attr_config_table;
154static struct kobj_attribute efi_attr_fw_platform_size =
155 __ATTR_RO(fw_platform_size);
156
157static struct attribute *efi_subsys_attrs[] = {
158 &efi_attr_systab.attr,
159 &efi_attr_fw_platform_size.attr,
160 &efi_attr_fw_vendor.attr,
161 &efi_attr_runtime.attr,
162 &efi_attr_config_table.attr,
163 NULL,
164};
165
166umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
167 int n)
168{
169 return attr->mode;
170}
171
172static const struct attribute_group efi_subsys_attr_group = {
173 .attrs = efi_subsys_attrs,
174 .is_visible = efi_attr_is_visible,
175};
176
177static struct efivars generic_efivars;
178static struct efivar_operations generic_ops;
179
180static int generic_ops_register(void)
181{
182 generic_ops.get_variable = efi.get_variable;
183 generic_ops.get_next_variable = efi.get_next_variable;
184 generic_ops.query_variable_store = efi_query_variable_store;
185
186 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
187 generic_ops.set_variable = efi.set_variable;
188 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
189 }
190 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
191}
192
193static void generic_ops_unregister(void)
194{
195 efivars_unregister(&generic_efivars);
196}
197
198#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
199#define EFIVAR_SSDT_NAME_MAX 16
200static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
201static int __init efivar_ssdt_setup(char *str)
202{
203 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
204
205 if (ret)
206 return ret;
207
208 if (strlen(str) < sizeof(efivar_ssdt))
209 memcpy(efivar_ssdt, str, strlen(str));
210 else
211 pr_warn("efivar_ssdt: name too long: %s\n", str);
212 return 0;
213}
214__setup("efivar_ssdt=", efivar_ssdt_setup);
215
216static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
217 unsigned long name_size, void *data)
218{
219 struct efivar_entry *entry;
220 struct list_head *list = data;
221 char utf8_name[EFIVAR_SSDT_NAME_MAX];
222 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
223
224 ucs2_as_utf8(utf8_name, name, limit - 1);
225 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
226 return 0;
227
228 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
229 if (!entry)
230 return 0;
231
232 memcpy(entry->var.VariableName, name, name_size);
233 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
234
235 efivar_entry_add(entry, list);
236
237 return 0;
238}
239
240static __init int efivar_ssdt_load(void)
241{
242 LIST_HEAD(entries);
243 struct efivar_entry *entry, *aux;
244 unsigned long size;
245 void *data;
246 int ret;
247
248 if (!efivar_ssdt[0])
249 return 0;
250
251 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
252
253 list_for_each_entry_safe(entry, aux, &entries, list) {
254 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
255 &entry->var.VendorGuid);
256
257 list_del(&entry->list);
258
259 ret = efivar_entry_size(entry, &size);
260 if (ret) {
261 pr_err("failed to get var size\n");
262 goto free_entry;
263 }
264
265 data = kmalloc(size, GFP_KERNEL);
266 if (!data) {
267 ret = -ENOMEM;
268 goto free_entry;
269 }
270
271 ret = efivar_entry_get(entry, NULL, &size, data);
272 if (ret) {
273 pr_err("failed to get var data\n");
274 goto free_data;
275 }
276
277 ret = acpi_load_table(data, NULL);
278 if (ret) {
279 pr_err("failed to load table: %d\n", ret);
280 goto free_data;
281 }
282
283 goto free_entry;
284
285free_data:
286 kfree(data);
287
288free_entry:
289 kfree(entry);
290 }
291
292 return ret;
293}
294#else
295static inline int efivar_ssdt_load(void) { return 0; }
296#endif
297
298#ifdef CONFIG_DEBUG_FS
299
300#define EFI_DEBUGFS_MAX_BLOBS 32
301
302static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
303
304static void __init efi_debugfs_init(void)
305{
306 struct dentry *efi_debugfs;
307 efi_memory_desc_t *md;
308 char name[32];
309 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
310 int i = 0;
311
312 efi_debugfs = debugfs_create_dir("efi", NULL);
313 if (IS_ERR_OR_NULL(efi_debugfs))
314 return;
315
316 for_each_efi_memory_desc(md) {
317 switch (md->type) {
318 case EFI_BOOT_SERVICES_CODE:
319 snprintf(name, sizeof(name), "boot_services_code%d",
320 type_count[md->type]++);
321 break;
322 case EFI_BOOT_SERVICES_DATA:
323 snprintf(name, sizeof(name), "boot_services_data%d",
324 type_count[md->type]++);
325 break;
326 default:
327 continue;
328 }
329
330 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
331 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
332 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
333 break;
334 }
335
336 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
337 debugfs_blob[i].data = memremap(md->phys_addr,
338 debugfs_blob[i].size,
339 MEMREMAP_WB);
340 if (!debugfs_blob[i].data)
341 continue;
342
343 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
344 i++;
345 }
346}
347#else
348static inline void efi_debugfs_init(void) {}
349#endif
350
351/*
352 * We register the efi subsystem with the firmware subsystem and the
353 * efivars subsystem with the efi subsystem, if the system was booted with
354 * EFI.
355 */
356static int __init efisubsys_init(void)
357{
358 int error;
359
360 if (!efi_enabled(EFI_RUNTIME_SERVICES))
361 efi.runtime_supported_mask = 0;
362
363 if (!efi_enabled(EFI_BOOT))
364 return 0;
365
366 if (efi.runtime_supported_mask) {
367 /*
368 * Since we process only one efi_runtime_service() at a time, an
369 * ordered workqueue (which creates only one execution context)
370 * should suffice for all our needs.
371 */
372 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
373 if (!efi_rts_wq) {
374 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
375 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
376 efi.runtime_supported_mask = 0;
377 return 0;
378 }
379 }
380
381 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
382 platform_device_register_simple("rtc-efi", 0, NULL, 0);
383
384 /* We register the efi directory at /sys/firmware/efi */
385 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
386 if (!efi_kobj) {
387 pr_err("efi: Firmware registration failed.\n");
388 destroy_workqueue(efi_rts_wq);
389 return -ENOMEM;
390 }
391
392 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
393 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
394 error = generic_ops_register();
395 if (error)
396 goto err_put;
397 efivar_ssdt_load();
398 platform_device_register_simple("efivars", 0, NULL, 0);
399 }
400
401 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
402 if (error) {
403 pr_err("efi: Sysfs attribute export failed with error %d.\n",
404 error);
405 goto err_unregister;
406 }
407
408 error = efi_runtime_map_init(efi_kobj);
409 if (error)
410 goto err_remove_group;
411
412 /* and the standard mountpoint for efivarfs */
413 error = sysfs_create_mount_point(efi_kobj, "efivars");
414 if (error) {
415 pr_err("efivars: Subsystem registration failed.\n");
416 goto err_remove_group;
417 }
418
419 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
420 efi_debugfs_init();
421
422 return 0;
423
424err_remove_group:
425 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
426err_unregister:
427 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
428 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
429 generic_ops_unregister();
430err_put:
431 kobject_put(efi_kobj);
432 destroy_workqueue(efi_rts_wq);
433 return error;
434}
435
436subsys_initcall(efisubsys_init);
437
438/*
439 * Find the efi memory descriptor for a given physical address. Given a
440 * physical address, determine if it exists within an EFI Memory Map entry,
441 * and if so, populate the supplied memory descriptor with the appropriate
442 * data.
443 */
444int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
445{
446 efi_memory_desc_t *md;
447
448 if (!efi_enabled(EFI_MEMMAP)) {
449 pr_err_once("EFI_MEMMAP is not enabled.\n");
450 return -EINVAL;
451 }
452
453 if (!out_md) {
454 pr_err_once("out_md is null.\n");
455 return -EINVAL;
456 }
457
458 for_each_efi_memory_desc(md) {
459 u64 size;
460 u64 end;
461
462 size = md->num_pages << EFI_PAGE_SHIFT;
463 end = md->phys_addr + size;
464 if (phys_addr >= md->phys_addr && phys_addr < end) {
465 memcpy(out_md, md, sizeof(*out_md));
466 return 0;
467 }
468 }
469 return -ENOENT;
470}
471
472/*
473 * Calculate the highest address of an efi memory descriptor.
474 */
475u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
476{
477 u64 size = md->num_pages << EFI_PAGE_SHIFT;
478 u64 end = md->phys_addr + size;
479 return end;
480}
481
482void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
483
484/**
485 * efi_mem_reserve - Reserve an EFI memory region
486 * @addr: Physical address to reserve
487 * @size: Size of reservation
488 *
489 * Mark a region as reserved from general kernel allocation and
490 * prevent it being released by efi_free_boot_services().
491 *
492 * This function should be called drivers once they've parsed EFI
493 * configuration tables to figure out where their data lives, e.g.
494 * efi_esrt_init().
495 */
496void __init efi_mem_reserve(phys_addr_t addr, u64 size)
497{
498 if (!memblock_is_region_reserved(addr, size))
499 memblock_reserve(addr, size);
500
501 /*
502 * Some architectures (x86) reserve all boot services ranges
503 * until efi_free_boot_services() because of buggy firmware
504 * implementations. This means the above memblock_reserve() is
505 * superfluous on x86 and instead what it needs to do is
506 * ensure the @start, @size is not freed.
507 */
508 efi_arch_mem_reserve(addr, size);
509}
510
511static const efi_config_table_type_t common_tables[] __initconst = {
512 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
513 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
514 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
515 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
516 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
517 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
518 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
519 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
520 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" },
521 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
522 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
523#ifdef CONFIG_EFI_RCI2_TABLE
524 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
525#endif
526#ifdef CONFIG_LOAD_UEFI_KEYS
527 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
528#endif
529 {},
530};
531
532static __init int match_config_table(const efi_guid_t *guid,
533 unsigned long table,
534 const efi_config_table_type_t *table_types)
535{
536 int i;
537
538 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
539 if (!efi_guidcmp(*guid, table_types[i].guid)) {
540 *(table_types[i].ptr) = table;
541 if (table_types[i].name[0])
542 pr_cont("%s=0x%lx ",
543 table_types[i].name, table);
544 return 1;
545 }
546 }
547
548 return 0;
549}
550
551int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
552 int count,
553 const efi_config_table_type_t *arch_tables)
554{
555 const efi_config_table_64_t *tbl64 = (void *)config_tables;
556 const efi_config_table_32_t *tbl32 = (void *)config_tables;
557 const efi_guid_t *guid;
558 unsigned long table;
559 int i;
560
561 pr_info("");
562 for (i = 0; i < count; i++) {
563 if (!IS_ENABLED(CONFIG_X86)) {
564 guid = &config_tables[i].guid;
565 table = (unsigned long)config_tables[i].table;
566 } else if (efi_enabled(EFI_64BIT)) {
567 guid = &tbl64[i].guid;
568 table = tbl64[i].table;
569
570 if (IS_ENABLED(CONFIG_X86_32) &&
571 tbl64[i].table > U32_MAX) {
572 pr_cont("\n");
573 pr_err("Table located above 4GB, disabling EFI.\n");
574 return -EINVAL;
575 }
576 } else {
577 guid = &tbl32[i].guid;
578 table = tbl32[i].table;
579 }
580
581 if (!match_config_table(guid, table, common_tables) && arch_tables)
582 match_config_table(guid, table, arch_tables);
583 }
584 pr_cont("\n");
585 set_bit(EFI_CONFIG_TABLES, &efi.flags);
586
587 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
588 struct linux_efi_random_seed *seed;
589 u32 size = 0;
590
591 seed = early_memremap(efi_rng_seed, sizeof(*seed));
592 if (seed != NULL) {
593 size = READ_ONCE(seed->size);
594 early_memunmap(seed, sizeof(*seed));
595 } else {
596 pr_err("Could not map UEFI random seed!\n");
597 }
598 if (size > 0) {
599 seed = early_memremap(efi_rng_seed,
600 sizeof(*seed) + size);
601 if (seed != NULL) {
602 pr_notice("seeding entropy pool\n");
603 add_bootloader_randomness(seed->bits, size);
604 early_memunmap(seed, sizeof(*seed) + size);
605 } else {
606 pr_err("Could not map UEFI random seed!\n");
607 }
608 }
609 }
610
611 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
612 efi_memattr_init();
613
614 efi_tpm_eventlog_init();
615
616 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
617 unsigned long prsv = mem_reserve;
618
619 while (prsv) {
620 struct linux_efi_memreserve *rsv;
621 u8 *p;
622
623 /*
624 * Just map a full page: that is what we will get
625 * anyway, and it permits us to map the entire entry
626 * before knowing its size.
627 */
628 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
629 PAGE_SIZE);
630 if (p == NULL) {
631 pr_err("Could not map UEFI memreserve entry!\n");
632 return -ENOMEM;
633 }
634
635 rsv = (void *)(p + prsv % PAGE_SIZE);
636
637 /* reserve the entry itself */
638 memblock_reserve(prsv,
639 struct_size(rsv, entry, rsv->size));
640
641 for (i = 0; i < atomic_read(&rsv->count); i++) {
642 memblock_reserve(rsv->entry[i].base,
643 rsv->entry[i].size);
644 }
645
646 prsv = rsv->next;
647 early_memunmap(p, PAGE_SIZE);
648 }
649 }
650
651 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
652 efi_rt_properties_table_t *tbl;
653
654 tbl = early_memremap(rt_prop, sizeof(*tbl));
655 if (tbl) {
656 efi.runtime_supported_mask &= tbl->runtime_services_supported;
657 early_memunmap(tbl, sizeof(*tbl));
658 }
659 }
660
661 return 0;
662}
663
664int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr,
665 int min_major_version)
666{
667 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
668 pr_err("System table signature incorrect!\n");
669 return -EINVAL;
670 }
671
672 if ((systab_hdr->revision >> 16) < min_major_version)
673 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n",
674 systab_hdr->revision >> 16,
675 systab_hdr->revision & 0xffff,
676 min_major_version);
677
678 return 0;
679}
680
681#ifndef CONFIG_IA64
682static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
683 size_t size)
684{
685 const efi_char16_t *ret;
686
687 ret = early_memremap_ro(fw_vendor, size);
688 if (!ret)
689 pr_err("Could not map the firmware vendor!\n");
690 return ret;
691}
692
693static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
694{
695 early_memunmap((void *)fw_vendor, size);
696}
697#else
698#define map_fw_vendor(p, s) __va(p)
699#define unmap_fw_vendor(v, s)
700#endif
701
702void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
703 unsigned long fw_vendor)
704{
705 char vendor[100] = "unknown";
706 const efi_char16_t *c16;
707 size_t i;
708
709 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
710 if (c16) {
711 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
712 vendor[i] = c16[i];
713 vendor[i] = '\0';
714
715 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
716 }
717
718 pr_info("EFI v%u.%.02u by %s\n",
719 systab_hdr->revision >> 16,
720 systab_hdr->revision & 0xffff,
721 vendor);
722}
723
724static __initdata char memory_type_name[][13] = {
725 "Reserved",
726 "Loader Code",
727 "Loader Data",
728 "Boot Code",
729 "Boot Data",
730 "Runtime Code",
731 "Runtime Data",
732 "Conventional",
733 "Unusable",
734 "ACPI Reclaim",
735 "ACPI Mem NVS",
736 "MMIO",
737 "MMIO Port",
738 "PAL Code",
739 "Persistent",
740};
741
742char * __init efi_md_typeattr_format(char *buf, size_t size,
743 const efi_memory_desc_t *md)
744{
745 char *pos;
746 int type_len;
747 u64 attr;
748
749 pos = buf;
750 if (md->type >= ARRAY_SIZE(memory_type_name))
751 type_len = snprintf(pos, size, "[type=%u", md->type);
752 else
753 type_len = snprintf(pos, size, "[%-*s",
754 (int)(sizeof(memory_type_name[0]) - 1),
755 memory_type_name[md->type]);
756 if (type_len >= size)
757 return buf;
758
759 pos += type_len;
760 size -= type_len;
761
762 attr = md->attribute;
763 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
764 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
765 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
766 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
767 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
768 snprintf(pos, size, "|attr=0x%016llx]",
769 (unsigned long long)attr);
770 else
771 snprintf(pos, size,
772 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
773 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
774 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
775 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
776 attr & EFI_MEMORY_SP ? "SP" : "",
777 attr & EFI_MEMORY_NV ? "NV" : "",
778 attr & EFI_MEMORY_XP ? "XP" : "",
779 attr & EFI_MEMORY_RP ? "RP" : "",
780 attr & EFI_MEMORY_WP ? "WP" : "",
781 attr & EFI_MEMORY_RO ? "RO" : "",
782 attr & EFI_MEMORY_UCE ? "UCE" : "",
783 attr & EFI_MEMORY_WB ? "WB" : "",
784 attr & EFI_MEMORY_WT ? "WT" : "",
785 attr & EFI_MEMORY_WC ? "WC" : "",
786 attr & EFI_MEMORY_UC ? "UC" : "");
787 return buf;
788}
789
790/*
791 * IA64 has a funky EFI memory map that doesn't work the same way as
792 * other architectures.
793 */
794#ifndef CONFIG_IA64
795/*
796 * efi_mem_attributes - lookup memmap attributes for physical address
797 * @phys_addr: the physical address to lookup
798 *
799 * Search in the EFI memory map for the region covering
800 * @phys_addr. Returns the EFI memory attributes if the region
801 * was found in the memory map, 0 otherwise.
802 */
803u64 efi_mem_attributes(unsigned long phys_addr)
804{
805 efi_memory_desc_t *md;
806
807 if (!efi_enabled(EFI_MEMMAP))
808 return 0;
809
810 for_each_efi_memory_desc(md) {
811 if ((md->phys_addr <= phys_addr) &&
812 (phys_addr < (md->phys_addr +
813 (md->num_pages << EFI_PAGE_SHIFT))))
814 return md->attribute;
815 }
816 return 0;
817}
818
819/*
820 * efi_mem_type - lookup memmap type for physical address
821 * @phys_addr: the physical address to lookup
822 *
823 * Search in the EFI memory map for the region covering @phys_addr.
824 * Returns the EFI memory type if the region was found in the memory
825 * map, -EINVAL otherwise.
826 */
827int efi_mem_type(unsigned long phys_addr)
828{
829 const efi_memory_desc_t *md;
830
831 if (!efi_enabled(EFI_MEMMAP))
832 return -ENOTSUPP;
833
834 for_each_efi_memory_desc(md) {
835 if ((md->phys_addr <= phys_addr) &&
836 (phys_addr < (md->phys_addr +
837 (md->num_pages << EFI_PAGE_SHIFT))))
838 return md->type;
839 }
840 return -EINVAL;
841}
842#endif
843
844int efi_status_to_err(efi_status_t status)
845{
846 int err;
847
848 switch (status) {
849 case EFI_SUCCESS:
850 err = 0;
851 break;
852 case EFI_INVALID_PARAMETER:
853 err = -EINVAL;
854 break;
855 case EFI_OUT_OF_RESOURCES:
856 err = -ENOSPC;
857 break;
858 case EFI_DEVICE_ERROR:
859 err = -EIO;
860 break;
861 case EFI_WRITE_PROTECTED:
862 err = -EROFS;
863 break;
864 case EFI_SECURITY_VIOLATION:
865 err = -EACCES;
866 break;
867 case EFI_NOT_FOUND:
868 err = -ENOENT;
869 break;
870 case EFI_ABORTED:
871 err = -EINTR;
872 break;
873 default:
874 err = -EINVAL;
875 }
876
877 return err;
878}
879
880static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
881static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
882
883static int __init efi_memreserve_map_root(void)
884{
885 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
886 return -ENODEV;
887
888 efi_memreserve_root = memremap(mem_reserve,
889 sizeof(*efi_memreserve_root),
890 MEMREMAP_WB);
891 if (WARN_ON_ONCE(!efi_memreserve_root))
892 return -ENOMEM;
893 return 0;
894}
895
896static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
897{
898 struct resource *res, *parent;
899 int ret;
900
901 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
902 if (!res)
903 return -ENOMEM;
904
905 res->name = "reserved";
906 res->flags = IORESOURCE_MEM;
907 res->start = addr;
908 res->end = addr + size - 1;
909
910 /* we expect a conflict with a 'System RAM' region */
911 parent = request_resource_conflict(&iomem_resource, res);
912 ret = parent ? request_resource(parent, res) : 0;
913
914 /*
915 * Given that efi_mem_reserve_iomem() can be called at any
916 * time, only call memblock_reserve() if the architecture
917 * keeps the infrastructure around.
918 */
919 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
920 memblock_reserve(addr, size);
921
922 return ret;
923}
924
925int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
926{
927 struct linux_efi_memreserve *rsv;
928 unsigned long prsv;
929 int rc, index;
930
931 if (efi_memreserve_root == (void *)ULONG_MAX)
932 return -ENODEV;
933
934 if (!efi_memreserve_root) {
935 rc = efi_memreserve_map_root();
936 if (rc)
937 return rc;
938 }
939
940 /* first try to find a slot in an existing linked list entry */
941 for (prsv = efi_memreserve_root->next; prsv; ) {
942 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
943 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
944 if (index < rsv->size) {
945 rsv->entry[index].base = addr;
946 rsv->entry[index].size = size;
947
948 memunmap(rsv);
949 return efi_mem_reserve_iomem(addr, size);
950 }
951 prsv = rsv->next;
952 memunmap(rsv);
953 }
954
955 /* no slot found - allocate a new linked list entry */
956 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
957 if (!rsv)
958 return -ENOMEM;
959
960 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
961 if (rc) {
962 free_page((unsigned long)rsv);
963 return rc;
964 }
965
966 /*
967 * The memremap() call above assumes that a linux_efi_memreserve entry
968 * never crosses a page boundary, so let's ensure that this remains true
969 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
970 * using SZ_4K explicitly in the size calculation below.
971 */
972 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
973 atomic_set(&rsv->count, 1);
974 rsv->entry[0].base = addr;
975 rsv->entry[0].size = size;
976
977 spin_lock(&efi_mem_reserve_persistent_lock);
978 rsv->next = efi_memreserve_root->next;
979 efi_memreserve_root->next = __pa(rsv);
980 spin_unlock(&efi_mem_reserve_persistent_lock);
981
982 return efi_mem_reserve_iomem(addr, size);
983}
984
985static int __init efi_memreserve_root_init(void)
986{
987 if (efi_memreserve_root)
988 return 0;
989 if (efi_memreserve_map_root())
990 efi_memreserve_root = (void *)ULONG_MAX;
991 return 0;
992}
993early_initcall(efi_memreserve_root_init);
994
995#ifdef CONFIG_KEXEC
996static int update_efi_random_seed(struct notifier_block *nb,
997 unsigned long code, void *unused)
998{
999 struct linux_efi_random_seed *seed;
1000 u32 size = 0;
1001
1002 if (!kexec_in_progress)
1003 return NOTIFY_DONE;
1004
1005 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1006 if (seed != NULL) {
1007 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1008 memunmap(seed);
1009 } else {
1010 pr_err("Could not map UEFI random seed!\n");
1011 }
1012 if (size > 0) {
1013 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1014 MEMREMAP_WB);
1015 if (seed != NULL) {
1016 seed->size = size;
1017 get_random_bytes(seed->bits, seed->size);
1018 memunmap(seed);
1019 } else {
1020 pr_err("Could not map UEFI random seed!\n");
1021 }
1022 }
1023 return NOTIFY_DONE;
1024}
1025
1026static struct notifier_block efi_random_seed_nb = {
1027 .notifier_call = update_efi_random_seed,
1028};
1029
1030static int __init register_update_efi_random_seed(void)
1031{
1032 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1033 return 0;
1034 return register_reboot_notifier(&efi_random_seed_nb);
1035}
1036late_initcall(register_update_efi_random_seed);
1037#endif