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