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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * efi.c - EFI subsystem
4 *
5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 *
9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
10 * allowing the efivarfs to be mounted or the efivars module to be loaded.
11 * The existance of /sys/firmware/efi may also be used by userspace to
12 * determine that the system supports EFI.
13 */
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <linux/kobject.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/debugfs.h>
21#include <linux/device.h>
22#include <linux/efi.h>
23#include <linux/of.h>
24#include <linux/initrd.h>
25#include <linux/io.h>
26#include <linux/kexec.h>
27#include <linux/platform_device.h>
28#include <linux/random.h>
29#include <linux/reboot.h>
30#include <linux/slab.h>
31#include <linux/acpi.h>
32#include <linux/ucs2_string.h>
33#include <linux/memblock.h>
34#include <linux/security.h>
35
36#include <asm/early_ioremap.h>
37
38struct efi __read_mostly efi = {
39 .runtime_supported_mask = EFI_RT_SUPPORTED_ALL,
40 .acpi = EFI_INVALID_TABLE_ADDR,
41 .acpi20 = EFI_INVALID_TABLE_ADDR,
42 .smbios = EFI_INVALID_TABLE_ADDR,
43 .smbios3 = EFI_INVALID_TABLE_ADDR,
44 .esrt = EFI_INVALID_TABLE_ADDR,
45 .tpm_log = EFI_INVALID_TABLE_ADDR,
46 .tpm_final_log = EFI_INVALID_TABLE_ADDR,
47#ifdef CONFIG_LOAD_UEFI_KEYS
48 .mokvar_table = EFI_INVALID_TABLE_ADDR,
49#endif
50#ifdef CONFIG_EFI_COCO_SECRET
51 .coco_secret = EFI_INVALID_TABLE_ADDR,
52#endif
53};
54EXPORT_SYMBOL(efi);
55
56unsigned long __ro_after_init efi_rng_seed = EFI_INVALID_TABLE_ADDR;
57static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
58static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
59static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR;
60
61extern unsigned long screen_info_table;
62
63struct mm_struct efi_mm = {
64 .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
65 .mm_users = ATOMIC_INIT(2),
66 .mm_count = ATOMIC_INIT(1),
67 .write_protect_seq = SEQCNT_ZERO(efi_mm.write_protect_seq),
68 MMAP_LOCK_INITIALIZER(efi_mm)
69 .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
70 .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
71 .cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
72};
73
74struct workqueue_struct *efi_rts_wq;
75
76static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
77static int __init setup_noefi(char *arg)
78{
79 disable_runtime = true;
80 return 0;
81}
82early_param("noefi", setup_noefi);
83
84bool efi_runtime_disabled(void)
85{
86 return disable_runtime;
87}
88
89bool __pure __efi_soft_reserve_enabled(void)
90{
91 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE);
92}
93
94static int __init parse_efi_cmdline(char *str)
95{
96 if (!str) {
97 pr_warn("need at least one option\n");
98 return -EINVAL;
99 }
100
101 if (parse_option_str(str, "debug"))
102 set_bit(EFI_DBG, &efi.flags);
103
104 if (parse_option_str(str, "noruntime"))
105 disable_runtime = true;
106
107 if (parse_option_str(str, "runtime"))
108 disable_runtime = false;
109
110 if (parse_option_str(str, "nosoftreserve"))
111 set_bit(EFI_MEM_NO_SOFT_RESERVE, &efi.flags);
112
113 return 0;
114}
115early_param("efi", parse_efi_cmdline);
116
117struct kobject *efi_kobj;
118
119/*
120 * Let's not leave out systab information that snuck into
121 * the efivars driver
122 * Note, do not add more fields in systab sysfs file as it breaks sysfs
123 * one value per file rule!
124 */
125static ssize_t systab_show(struct kobject *kobj,
126 struct kobj_attribute *attr, char *buf)
127{
128 char *str = buf;
129
130 if (!kobj || !buf)
131 return -EINVAL;
132
133 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
134 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
135 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
136 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
137 /*
138 * If both SMBIOS and SMBIOS3 entry points are implemented, the
139 * SMBIOS3 entry point shall be preferred, so we list it first to
140 * let applications stop parsing after the first match.
141 */
142 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
143 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
144 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
145 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
146
147 if (IS_ENABLED(CONFIG_IA64) || IS_ENABLED(CONFIG_X86))
148 str = efi_systab_show_arch(str);
149
150 return str - buf;
151}
152
153static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
154
155static ssize_t fw_platform_size_show(struct kobject *kobj,
156 struct kobj_attribute *attr, char *buf)
157{
158 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
159}
160
161extern __weak struct kobj_attribute efi_attr_fw_vendor;
162extern __weak struct kobj_attribute efi_attr_runtime;
163extern __weak struct kobj_attribute efi_attr_config_table;
164static struct kobj_attribute efi_attr_fw_platform_size =
165 __ATTR_RO(fw_platform_size);
166
167static struct attribute *efi_subsys_attrs[] = {
168 &efi_attr_systab.attr,
169 &efi_attr_fw_platform_size.attr,
170 &efi_attr_fw_vendor.attr,
171 &efi_attr_runtime.attr,
172 &efi_attr_config_table.attr,
173 NULL,
174};
175
176umode_t __weak efi_attr_is_visible(struct kobject *kobj, struct attribute *attr,
177 int n)
178{
179 return attr->mode;
180}
181
182static const struct attribute_group efi_subsys_attr_group = {
183 .attrs = efi_subsys_attrs,
184 .is_visible = efi_attr_is_visible,
185};
186
187static struct efivars generic_efivars;
188static struct efivar_operations generic_ops;
189
190static int generic_ops_register(void)
191{
192 generic_ops.get_variable = efi.get_variable;
193 generic_ops.get_next_variable = efi.get_next_variable;
194 generic_ops.query_variable_store = efi_query_variable_store;
195
196 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) {
197 generic_ops.set_variable = efi.set_variable;
198 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
199 }
200 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
201}
202
203static void generic_ops_unregister(void)
204{
205 efivars_unregister(&generic_efivars);
206}
207
208#ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
209#define EFIVAR_SSDT_NAME_MAX 16UL
210static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
211static int __init efivar_ssdt_setup(char *str)
212{
213 int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
214
215 if (ret)
216 return ret;
217
218 if (strlen(str) < sizeof(efivar_ssdt))
219 memcpy(efivar_ssdt, str, strlen(str));
220 else
221 pr_warn("efivar_ssdt: name too long: %s\n", str);
222 return 1;
223}
224__setup("efivar_ssdt=", efivar_ssdt_setup);
225
226static __init int efivar_ssdt_load(void)
227{
228 unsigned long name_size = 256;
229 efi_char16_t *name = NULL;
230 efi_status_t status;
231 efi_guid_t guid;
232
233 if (!efivar_ssdt[0])
234 return 0;
235
236 name = kzalloc(name_size, GFP_KERNEL);
237 if (!name)
238 return -ENOMEM;
239
240 for (;;) {
241 char utf8_name[EFIVAR_SSDT_NAME_MAX];
242 unsigned long data_size = 0;
243 void *data;
244 int limit;
245
246 status = efi.get_next_variable(&name_size, name, &guid);
247 if (status == EFI_NOT_FOUND) {
248 break;
249 } else if (status == EFI_BUFFER_TOO_SMALL) {
250 name = krealloc(name, name_size, GFP_KERNEL);
251 if (!name)
252 return -ENOMEM;
253 continue;
254 }
255
256 limit = min(EFIVAR_SSDT_NAME_MAX, name_size);
257 ucs2_as_utf8(utf8_name, name, limit - 1);
258 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
259 continue;
260
261 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt, &guid);
262
263 status = efi.get_variable(name, &guid, NULL, &data_size, NULL);
264 if (status != EFI_BUFFER_TOO_SMALL || !data_size)
265 return -EIO;
266
267 data = kmalloc(data_size, GFP_KERNEL);
268 if (!data)
269 return -ENOMEM;
270
271 status = efi.get_variable(name, &guid, NULL, &data_size, data);
272 if (status == EFI_SUCCESS) {
273 acpi_status ret = acpi_load_table(data, NULL);
274 if (ret)
275 pr_err("failed to load table: %u\n", ret);
276 else
277 continue;
278 } else {
279 pr_err("failed to get var data: 0x%lx\n", status);
280 }
281 kfree(data);
282 }
283 return 0;
284}
285#else
286static inline int efivar_ssdt_load(void) { return 0; }
287#endif
288
289#ifdef CONFIG_DEBUG_FS
290
291#define EFI_DEBUGFS_MAX_BLOBS 32
292
293static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
294
295static void __init efi_debugfs_init(void)
296{
297 struct dentry *efi_debugfs;
298 efi_memory_desc_t *md;
299 char name[32];
300 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
301 int i = 0;
302
303 efi_debugfs = debugfs_create_dir("efi", NULL);
304 if (IS_ERR_OR_NULL(efi_debugfs))
305 return;
306
307 for_each_efi_memory_desc(md) {
308 switch (md->type) {
309 case EFI_BOOT_SERVICES_CODE:
310 snprintf(name, sizeof(name), "boot_services_code%d",
311 type_count[md->type]++);
312 break;
313 case EFI_BOOT_SERVICES_DATA:
314 snprintf(name, sizeof(name), "boot_services_data%d",
315 type_count[md->type]++);
316 break;
317 default:
318 continue;
319 }
320
321 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
322 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
323 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
324 break;
325 }
326
327 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
328 debugfs_blob[i].data = memremap(md->phys_addr,
329 debugfs_blob[i].size,
330 MEMREMAP_WB);
331 if (!debugfs_blob[i].data)
332 continue;
333
334 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
335 i++;
336 }
337}
338#else
339static inline void efi_debugfs_init(void) {}
340#endif
341
342static void refresh_nv_rng_seed(struct work_struct *work)
343{
344 u8 seed[EFI_RANDOM_SEED_SIZE];
345
346 get_random_bytes(seed, sizeof(seed));
347 efi.set_variable(L"RandomSeed", &LINUX_EFI_RANDOM_SEED_TABLE_GUID,
348 EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS |
349 EFI_VARIABLE_RUNTIME_ACCESS, sizeof(seed), seed);
350 memzero_explicit(seed, sizeof(seed));
351}
352static int refresh_nv_rng_seed_notification(struct notifier_block *nb, unsigned long action, void *data)
353{
354 static DECLARE_WORK(work, refresh_nv_rng_seed);
355 schedule_work(&work);
356 return NOTIFY_DONE;
357}
358static struct notifier_block refresh_nv_rng_seed_nb = { .notifier_call = refresh_nv_rng_seed_notification };
359
360/*
361 * We register the efi subsystem with the firmware subsystem and the
362 * efivars subsystem with the efi subsystem, if the system was booted with
363 * EFI.
364 */
365static int __init efisubsys_init(void)
366{
367 int error;
368
369 if (!efi_enabled(EFI_RUNTIME_SERVICES))
370 efi.runtime_supported_mask = 0;
371
372 if (!efi_enabled(EFI_BOOT))
373 return 0;
374
375 if (efi.runtime_supported_mask) {
376 /*
377 * Since we process only one efi_runtime_service() at a time, an
378 * ordered workqueue (which creates only one execution context)
379 * should suffice for all our needs.
380 */
381 efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
382 if (!efi_rts_wq) {
383 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
384 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
385 efi.runtime_supported_mask = 0;
386 return 0;
387 }
388 }
389
390 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES))
391 platform_device_register_simple("rtc-efi", 0, NULL, 0);
392
393 /* We register the efi directory at /sys/firmware/efi */
394 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
395 if (!efi_kobj) {
396 pr_err("efi: Firmware registration failed.\n");
397 error = -ENOMEM;
398 goto err_destroy_wq;
399 }
400
401 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
402 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME)) {
403 error = generic_ops_register();
404 if (error)
405 goto err_put;
406 efivar_ssdt_load();
407 platform_device_register_simple("efivars", 0, NULL, 0);
408 }
409
410 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
411 if (error) {
412 pr_err("efi: Sysfs attribute export failed with error %d.\n",
413 error);
414 goto err_unregister;
415 }
416
417 /* and the standard mountpoint for efivarfs */
418 error = sysfs_create_mount_point(efi_kobj, "efivars");
419 if (error) {
420 pr_err("efivars: Subsystem registration failed.\n");
421 goto err_remove_group;
422 }
423
424 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
425 efi_debugfs_init();
426
427#ifdef CONFIG_EFI_COCO_SECRET
428 if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
429 platform_device_register_simple("efi_secret", 0, NULL, 0);
430#endif
431
432 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE))
433 execute_with_initialized_rng(&refresh_nv_rng_seed_nb);
434
435 return 0;
436
437err_remove_group:
438 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
439err_unregister:
440 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE |
441 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME))
442 generic_ops_unregister();
443err_put:
444 kobject_put(efi_kobj);
445 efi_kobj = NULL;
446err_destroy_wq:
447 if (efi_rts_wq)
448 destroy_workqueue(efi_rts_wq);
449
450 return error;
451}
452
453subsys_initcall(efisubsys_init);
454
455void __init efi_find_mirror(void)
456{
457 efi_memory_desc_t *md;
458 u64 mirror_size = 0, total_size = 0;
459
460 if (!efi_enabled(EFI_MEMMAP))
461 return;
462
463 for_each_efi_memory_desc(md) {
464 unsigned long long start = md->phys_addr;
465 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
466
467 total_size += size;
468 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
469 memblock_mark_mirror(start, size);
470 mirror_size += size;
471 }
472 }
473 if (mirror_size)
474 pr_info("Memory: %lldM/%lldM mirrored memory\n",
475 mirror_size>>20, total_size>>20);
476}
477
478/*
479 * Find the efi memory descriptor for a given physical address. Given a
480 * physical address, determine if it exists within an EFI Memory Map entry,
481 * and if so, populate the supplied memory descriptor with the appropriate
482 * data.
483 */
484int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
485{
486 efi_memory_desc_t *md;
487
488 if (!efi_enabled(EFI_MEMMAP)) {
489 pr_err_once("EFI_MEMMAP is not enabled.\n");
490 return -EINVAL;
491 }
492
493 if (!out_md) {
494 pr_err_once("out_md is null.\n");
495 return -EINVAL;
496 }
497
498 for_each_efi_memory_desc(md) {
499 u64 size;
500 u64 end;
501
502 size = md->num_pages << EFI_PAGE_SHIFT;
503 end = md->phys_addr + size;
504 if (phys_addr >= md->phys_addr && phys_addr < end) {
505 memcpy(out_md, md, sizeof(*out_md));
506 return 0;
507 }
508 }
509 return -ENOENT;
510}
511
512/*
513 * Calculate the highest address of an efi memory descriptor.
514 */
515u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
516{
517 u64 size = md->num_pages << EFI_PAGE_SHIFT;
518 u64 end = md->phys_addr + size;
519 return end;
520}
521
522void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
523
524/**
525 * efi_mem_reserve - Reserve an EFI memory region
526 * @addr: Physical address to reserve
527 * @size: Size of reservation
528 *
529 * Mark a region as reserved from general kernel allocation and
530 * prevent it being released by efi_free_boot_services().
531 *
532 * This function should be called drivers once they've parsed EFI
533 * configuration tables to figure out where their data lives, e.g.
534 * efi_esrt_init().
535 */
536void __init efi_mem_reserve(phys_addr_t addr, u64 size)
537{
538 if (!memblock_is_region_reserved(addr, size))
539 memblock_reserve(addr, size);
540
541 /*
542 * Some architectures (x86) reserve all boot services ranges
543 * until efi_free_boot_services() because of buggy firmware
544 * implementations. This means the above memblock_reserve() is
545 * superfluous on x86 and instead what it needs to do is
546 * ensure the @start, @size is not freed.
547 */
548 efi_arch_mem_reserve(addr, size);
549}
550
551static const efi_config_table_type_t common_tables[] __initconst = {
552 {ACPI_20_TABLE_GUID, &efi.acpi20, "ACPI 2.0" },
553 {ACPI_TABLE_GUID, &efi.acpi, "ACPI" },
554 {SMBIOS_TABLE_GUID, &efi.smbios, "SMBIOS" },
555 {SMBIOS3_TABLE_GUID, &efi.smbios3, "SMBIOS 3.0" },
556 {EFI_SYSTEM_RESOURCE_TABLE_GUID, &efi.esrt, "ESRT" },
557 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, &efi_mem_attr_table, "MEMATTR" },
558 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, &efi_rng_seed, "RNG" },
559 {LINUX_EFI_TPM_EVENT_LOG_GUID, &efi.tpm_log, "TPMEventLog" },
560 {LINUX_EFI_TPM_FINAL_LOG_GUID, &efi.tpm_final_log, "TPMFinalLog" },
561 {LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
562 {LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
563 {EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
564#ifdef CONFIG_EFI_RCI2_TABLE
565 {DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
566#endif
567#ifdef CONFIG_LOAD_UEFI_KEYS
568 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID, &efi.mokvar_table, "MOKvar" },
569#endif
570#ifdef CONFIG_EFI_COCO_SECRET
571 {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" },
572#endif
573#ifdef CONFIG_EFI_GENERIC_STUB
574 {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table },
575#endif
576 {},
577};
578
579static __init int match_config_table(const efi_guid_t *guid,
580 unsigned long table,
581 const efi_config_table_type_t *table_types)
582{
583 int i;
584
585 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
586 if (!efi_guidcmp(*guid, table_types[i].guid)) {
587 *(table_types[i].ptr) = table;
588 if (table_types[i].name[0])
589 pr_cont("%s=0x%lx ",
590 table_types[i].name, table);
591 return 1;
592 }
593 }
594
595 return 0;
596}
597
598int __init efi_config_parse_tables(const efi_config_table_t *config_tables,
599 int count,
600 const efi_config_table_type_t *arch_tables)
601{
602 const efi_config_table_64_t *tbl64 = (void *)config_tables;
603 const efi_config_table_32_t *tbl32 = (void *)config_tables;
604 const efi_guid_t *guid;
605 unsigned long table;
606 int i;
607
608 pr_info("");
609 for (i = 0; i < count; i++) {
610 if (!IS_ENABLED(CONFIG_X86)) {
611 guid = &config_tables[i].guid;
612 table = (unsigned long)config_tables[i].table;
613 } else if (efi_enabled(EFI_64BIT)) {
614 guid = &tbl64[i].guid;
615 table = tbl64[i].table;
616
617 if (IS_ENABLED(CONFIG_X86_32) &&
618 tbl64[i].table > U32_MAX) {
619 pr_cont("\n");
620 pr_err("Table located above 4GB, disabling EFI.\n");
621 return -EINVAL;
622 }
623 } else {
624 guid = &tbl32[i].guid;
625 table = tbl32[i].table;
626 }
627
628 if (!match_config_table(guid, table, common_tables) && arch_tables)
629 match_config_table(guid, table, arch_tables);
630 }
631 pr_cont("\n");
632 set_bit(EFI_CONFIG_TABLES, &efi.flags);
633
634 if (efi_rng_seed != EFI_INVALID_TABLE_ADDR) {
635 struct linux_efi_random_seed *seed;
636 u32 size = 0;
637
638 seed = early_memremap(efi_rng_seed, sizeof(*seed));
639 if (seed != NULL) {
640 size = min_t(u32, seed->size, SZ_1K); // sanity check
641 early_memunmap(seed, sizeof(*seed));
642 } else {
643 pr_err("Could not map UEFI random seed!\n");
644 }
645 if (size > 0) {
646 seed = early_memremap(efi_rng_seed,
647 sizeof(*seed) + size);
648 if (seed != NULL) {
649 add_bootloader_randomness(seed->bits, size);
650 memzero_explicit(seed->bits, size);
651 early_memunmap(seed, sizeof(*seed) + size);
652 } else {
653 pr_err("Could not map UEFI random seed!\n");
654 }
655 }
656 }
657
658 if (!IS_ENABLED(CONFIG_X86_32) && efi_enabled(EFI_MEMMAP))
659 efi_memattr_init();
660
661 efi_tpm_eventlog_init();
662
663 if (mem_reserve != EFI_INVALID_TABLE_ADDR) {
664 unsigned long prsv = mem_reserve;
665
666 while (prsv) {
667 struct linux_efi_memreserve *rsv;
668 u8 *p;
669
670 /*
671 * Just map a full page: that is what we will get
672 * anyway, and it permits us to map the entire entry
673 * before knowing its size.
674 */
675 p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
676 PAGE_SIZE);
677 if (p == NULL) {
678 pr_err("Could not map UEFI memreserve entry!\n");
679 return -ENOMEM;
680 }
681
682 rsv = (void *)(p + prsv % PAGE_SIZE);
683
684 /* reserve the entry itself */
685 memblock_reserve(prsv,
686 struct_size(rsv, entry, rsv->size));
687
688 for (i = 0; i < atomic_read(&rsv->count); i++) {
689 memblock_reserve(rsv->entry[i].base,
690 rsv->entry[i].size);
691 }
692
693 prsv = rsv->next;
694 early_memunmap(p, PAGE_SIZE);
695 }
696 }
697
698 if (rt_prop != EFI_INVALID_TABLE_ADDR) {
699 efi_rt_properties_table_t *tbl;
700
701 tbl = early_memremap(rt_prop, sizeof(*tbl));
702 if (tbl) {
703 efi.runtime_supported_mask &= tbl->runtime_services_supported;
704 early_memunmap(tbl, sizeof(*tbl));
705 }
706 }
707
708 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
709 initrd != EFI_INVALID_TABLE_ADDR && phys_initrd_size == 0) {
710 struct linux_efi_initrd *tbl;
711
712 tbl = early_memremap(initrd, sizeof(*tbl));
713 if (tbl) {
714 phys_initrd_start = tbl->base;
715 phys_initrd_size = tbl->size;
716 early_memunmap(tbl, sizeof(*tbl));
717 }
718 }
719
720 return 0;
721}
722
723int __init efi_systab_check_header(const efi_table_hdr_t *systab_hdr,
724 int min_major_version)
725{
726 if (systab_hdr->signature != EFI_SYSTEM_TABLE_SIGNATURE) {
727 pr_err("System table signature incorrect!\n");
728 return -EINVAL;
729 }
730
731 if ((systab_hdr->revision >> 16) < min_major_version)
732 pr_err("Warning: System table version %d.%02d, expected %d.00 or greater!\n",
733 systab_hdr->revision >> 16,
734 systab_hdr->revision & 0xffff,
735 min_major_version);
736
737 return 0;
738}
739
740#ifndef CONFIG_IA64
741static const efi_char16_t *__init map_fw_vendor(unsigned long fw_vendor,
742 size_t size)
743{
744 const efi_char16_t *ret;
745
746 ret = early_memremap_ro(fw_vendor, size);
747 if (!ret)
748 pr_err("Could not map the firmware vendor!\n");
749 return ret;
750}
751
752static void __init unmap_fw_vendor(const void *fw_vendor, size_t size)
753{
754 early_memunmap((void *)fw_vendor, size);
755}
756#else
757#define map_fw_vendor(p, s) __va(p)
758#define unmap_fw_vendor(v, s)
759#endif
760
761void __init efi_systab_report_header(const efi_table_hdr_t *systab_hdr,
762 unsigned long fw_vendor)
763{
764 char vendor[100] = "unknown";
765 const efi_char16_t *c16;
766 size_t i;
767
768 c16 = map_fw_vendor(fw_vendor, sizeof(vendor) * sizeof(efi_char16_t));
769 if (c16) {
770 for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
771 vendor[i] = c16[i];
772 vendor[i] = '\0';
773
774 unmap_fw_vendor(c16, sizeof(vendor) * sizeof(efi_char16_t));
775 }
776
777 pr_info("EFI v%u.%.02u by %s\n",
778 systab_hdr->revision >> 16,
779 systab_hdr->revision & 0xffff,
780 vendor);
781
782 if (IS_ENABLED(CONFIG_X86_64) &&
783 systab_hdr->revision > EFI_1_10_SYSTEM_TABLE_REVISION &&
784 !strcmp(vendor, "Apple")) {
785 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
786 efi.runtime_version = EFI_1_10_SYSTEM_TABLE_REVISION;
787 }
788}
789
790static __initdata char memory_type_name[][13] = {
791 "Reserved",
792 "Loader Code",
793 "Loader Data",
794 "Boot Code",
795 "Boot Data",
796 "Runtime Code",
797 "Runtime Data",
798 "Conventional",
799 "Unusable",
800 "ACPI Reclaim",
801 "ACPI Mem NVS",
802 "MMIO",
803 "MMIO Port",
804 "PAL Code",
805 "Persistent",
806};
807
808char * __init efi_md_typeattr_format(char *buf, size_t size,
809 const efi_memory_desc_t *md)
810{
811 char *pos;
812 int type_len;
813 u64 attr;
814
815 pos = buf;
816 if (md->type >= ARRAY_SIZE(memory_type_name))
817 type_len = snprintf(pos, size, "[type=%u", md->type);
818 else
819 type_len = snprintf(pos, size, "[%-*s",
820 (int)(sizeof(memory_type_name[0]) - 1),
821 memory_type_name[md->type]);
822 if (type_len >= size)
823 return buf;
824
825 pos += type_len;
826 size -= type_len;
827
828 attr = md->attribute;
829 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
830 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
831 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
832 EFI_MEMORY_NV | EFI_MEMORY_SP | EFI_MEMORY_CPU_CRYPTO |
833 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
834 snprintf(pos, size, "|attr=0x%016llx]",
835 (unsigned long long)attr);
836 else
837 snprintf(pos, size,
838 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
839 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
840 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
841 attr & EFI_MEMORY_CPU_CRYPTO ? "CC" : "",
842 attr & EFI_MEMORY_SP ? "SP" : "",
843 attr & EFI_MEMORY_NV ? "NV" : "",
844 attr & EFI_MEMORY_XP ? "XP" : "",
845 attr & EFI_MEMORY_RP ? "RP" : "",
846 attr & EFI_MEMORY_WP ? "WP" : "",
847 attr & EFI_MEMORY_RO ? "RO" : "",
848 attr & EFI_MEMORY_UCE ? "UCE" : "",
849 attr & EFI_MEMORY_WB ? "WB" : "",
850 attr & EFI_MEMORY_WT ? "WT" : "",
851 attr & EFI_MEMORY_WC ? "WC" : "",
852 attr & EFI_MEMORY_UC ? "UC" : "");
853 return buf;
854}
855
856/*
857 * IA64 has a funky EFI memory map that doesn't work the same way as
858 * other architectures.
859 */
860#ifndef CONFIG_IA64
861/*
862 * efi_mem_attributes - lookup memmap attributes for physical address
863 * @phys_addr: the physical address to lookup
864 *
865 * Search in the EFI memory map for the region covering
866 * @phys_addr. Returns the EFI memory attributes if the region
867 * was found in the memory map, 0 otherwise.
868 */
869u64 efi_mem_attributes(unsigned long phys_addr)
870{
871 efi_memory_desc_t *md;
872
873 if (!efi_enabled(EFI_MEMMAP))
874 return 0;
875
876 for_each_efi_memory_desc(md) {
877 if ((md->phys_addr <= phys_addr) &&
878 (phys_addr < (md->phys_addr +
879 (md->num_pages << EFI_PAGE_SHIFT))))
880 return md->attribute;
881 }
882 return 0;
883}
884
885/*
886 * efi_mem_type - lookup memmap type for physical address
887 * @phys_addr: the physical address to lookup
888 *
889 * Search in the EFI memory map for the region covering @phys_addr.
890 * Returns the EFI memory type if the region was found in the memory
891 * map, -EINVAL otherwise.
892 */
893int efi_mem_type(unsigned long phys_addr)
894{
895 const efi_memory_desc_t *md;
896
897 if (!efi_enabled(EFI_MEMMAP))
898 return -ENOTSUPP;
899
900 for_each_efi_memory_desc(md) {
901 if ((md->phys_addr <= phys_addr) &&
902 (phys_addr < (md->phys_addr +
903 (md->num_pages << EFI_PAGE_SHIFT))))
904 return md->type;
905 }
906 return -EINVAL;
907}
908#endif
909
910int efi_status_to_err(efi_status_t status)
911{
912 int err;
913
914 switch (status) {
915 case EFI_SUCCESS:
916 err = 0;
917 break;
918 case EFI_INVALID_PARAMETER:
919 err = -EINVAL;
920 break;
921 case EFI_OUT_OF_RESOURCES:
922 err = -ENOSPC;
923 break;
924 case EFI_DEVICE_ERROR:
925 err = -EIO;
926 break;
927 case EFI_WRITE_PROTECTED:
928 err = -EROFS;
929 break;
930 case EFI_SECURITY_VIOLATION:
931 err = -EACCES;
932 break;
933 case EFI_NOT_FOUND:
934 err = -ENOENT;
935 break;
936 case EFI_ABORTED:
937 err = -EINTR;
938 break;
939 default:
940 err = -EINVAL;
941 }
942
943 return err;
944}
945EXPORT_SYMBOL_GPL(efi_status_to_err);
946
947static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
948static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
949
950static int __init efi_memreserve_map_root(void)
951{
952 if (mem_reserve == EFI_INVALID_TABLE_ADDR)
953 return -ENODEV;
954
955 efi_memreserve_root = memremap(mem_reserve,
956 sizeof(*efi_memreserve_root),
957 MEMREMAP_WB);
958 if (WARN_ON_ONCE(!efi_memreserve_root))
959 return -ENOMEM;
960 return 0;
961}
962
963static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size)
964{
965 struct resource *res, *parent;
966 int ret;
967
968 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
969 if (!res)
970 return -ENOMEM;
971
972 res->name = "reserved";
973 res->flags = IORESOURCE_MEM;
974 res->start = addr;
975 res->end = addr + size - 1;
976
977 /* we expect a conflict with a 'System RAM' region */
978 parent = request_resource_conflict(&iomem_resource, res);
979 ret = parent ? request_resource(parent, res) : 0;
980
981 /*
982 * Given that efi_mem_reserve_iomem() can be called at any
983 * time, only call memblock_reserve() if the architecture
984 * keeps the infrastructure around.
985 */
986 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK) && !ret)
987 memblock_reserve(addr, size);
988
989 return ret;
990}
991
992int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
993{
994 struct linux_efi_memreserve *rsv;
995 unsigned long prsv;
996 int rc, index;
997
998 if (efi_memreserve_root == (void *)ULONG_MAX)
999 return -ENODEV;
1000
1001 if (!efi_memreserve_root) {
1002 rc = efi_memreserve_map_root();
1003 if (rc)
1004 return rc;
1005 }
1006
1007 /* first try to find a slot in an existing linked list entry */
1008 for (prsv = efi_memreserve_root->next; prsv; ) {
1009 rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
1010 if (!rsv)
1011 return -ENOMEM;
1012 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
1013 if (index < rsv->size) {
1014 rsv->entry[index].base = addr;
1015 rsv->entry[index].size = size;
1016
1017 memunmap(rsv);
1018 return efi_mem_reserve_iomem(addr, size);
1019 }
1020 prsv = rsv->next;
1021 memunmap(rsv);
1022 }
1023
1024 /* no slot found - allocate a new linked list entry */
1025 rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
1026 if (!rsv)
1027 return -ENOMEM;
1028
1029 rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K);
1030 if (rc) {
1031 free_page((unsigned long)rsv);
1032 return rc;
1033 }
1034
1035 /*
1036 * The memremap() call above assumes that a linux_efi_memreserve entry
1037 * never crosses a page boundary, so let's ensure that this remains true
1038 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1039 * using SZ_4K explicitly in the size calculation below.
1040 */
1041 rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
1042 atomic_set(&rsv->count, 1);
1043 rsv->entry[0].base = addr;
1044 rsv->entry[0].size = size;
1045
1046 spin_lock(&efi_mem_reserve_persistent_lock);
1047 rsv->next = efi_memreserve_root->next;
1048 efi_memreserve_root->next = __pa(rsv);
1049 spin_unlock(&efi_mem_reserve_persistent_lock);
1050
1051 return efi_mem_reserve_iomem(addr, size);
1052}
1053
1054static int __init efi_memreserve_root_init(void)
1055{
1056 if (efi_memreserve_root)
1057 return 0;
1058 if (efi_memreserve_map_root())
1059 efi_memreserve_root = (void *)ULONG_MAX;
1060 return 0;
1061}
1062early_initcall(efi_memreserve_root_init);
1063
1064#ifdef CONFIG_KEXEC
1065static int update_efi_random_seed(struct notifier_block *nb,
1066 unsigned long code, void *unused)
1067{
1068 struct linux_efi_random_seed *seed;
1069 u32 size = 0;
1070
1071 if (!kexec_in_progress)
1072 return NOTIFY_DONE;
1073
1074 seed = memremap(efi_rng_seed, sizeof(*seed), MEMREMAP_WB);
1075 if (seed != NULL) {
1076 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
1077 memunmap(seed);
1078 } else {
1079 pr_err("Could not map UEFI random seed!\n");
1080 }
1081 if (size > 0) {
1082 seed = memremap(efi_rng_seed, sizeof(*seed) + size,
1083 MEMREMAP_WB);
1084 if (seed != NULL) {
1085 seed->size = size;
1086 get_random_bytes(seed->bits, seed->size);
1087 memunmap(seed);
1088 } else {
1089 pr_err("Could not map UEFI random seed!\n");
1090 }
1091 }
1092 return NOTIFY_DONE;
1093}
1094
1095static struct notifier_block efi_random_seed_nb = {
1096 .notifier_call = update_efi_random_seed,
1097};
1098
1099static int __init register_update_efi_random_seed(void)
1100{
1101 if (efi_rng_seed == EFI_INVALID_TABLE_ADDR)
1102 return 0;
1103 return register_reboot_notifier(&efi_random_seed_nb);
1104}
1105late_initcall(register_update_efi_random_seed);
1106#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