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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/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