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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/*
2 * efi.c - EFI subsystem
3 *
4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
6 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
7 *
8 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
9 * allowing the efivarfs to be mounted or the efivars module to be loaded.
10 * The existance of /sys/firmware/efi may also be used by userspace to
11 * determine that the system supports EFI.
12 *
13 * This file is released under the GPLv2.
14 */
15
16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18#include <linux/kobject.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/device.h>
22#include <linux/efi.h>
23#include <linux/of.h>
24#include <linux/of_fdt.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
35#include <asm/early_ioremap.h>
36
37struct efi __read_mostly efi = {
38 .mps = EFI_INVALID_TABLE_ADDR,
39 .acpi = EFI_INVALID_TABLE_ADDR,
40 .acpi20 = EFI_INVALID_TABLE_ADDR,
41 .smbios = EFI_INVALID_TABLE_ADDR,
42 .smbios3 = EFI_INVALID_TABLE_ADDR,
43 .sal_systab = EFI_INVALID_TABLE_ADDR,
44 .boot_info = EFI_INVALID_TABLE_ADDR,
45 .hcdp = EFI_INVALID_TABLE_ADDR,
46 .uga = EFI_INVALID_TABLE_ADDR,
47 .uv_systab = EFI_INVALID_TABLE_ADDR,
48 .fw_vendor = EFI_INVALID_TABLE_ADDR,
49 .runtime = EFI_INVALID_TABLE_ADDR,
50 .config_table = EFI_INVALID_TABLE_ADDR,
51 .esrt = EFI_INVALID_TABLE_ADDR,
52 .properties_table = EFI_INVALID_TABLE_ADDR,
53 .mem_attr_table = EFI_INVALID_TABLE_ADDR,
54 .rng_seed = EFI_INVALID_TABLE_ADDR,
55};
56EXPORT_SYMBOL(efi);
57
58static bool disable_runtime;
59static int __init setup_noefi(char *arg)
60{
61 disable_runtime = true;
62 return 0;
63}
64early_param("noefi", setup_noefi);
65
66bool efi_runtime_disabled(void)
67{
68 return disable_runtime;
69}
70
71static int __init parse_efi_cmdline(char *str)
72{
73 if (!str) {
74 pr_warn("need at least one option\n");
75 return -EINVAL;
76 }
77
78 if (parse_option_str(str, "debug"))
79 set_bit(EFI_DBG, &efi.flags);
80
81 if (parse_option_str(str, "noruntime"))
82 disable_runtime = true;
83
84 return 0;
85}
86early_param("efi", parse_efi_cmdline);
87
88struct kobject *efi_kobj;
89
90/*
91 * Let's not leave out systab information that snuck into
92 * the efivars driver
93 */
94static ssize_t systab_show(struct kobject *kobj,
95 struct kobj_attribute *attr, char *buf)
96{
97 char *str = buf;
98
99 if (!kobj || !buf)
100 return -EINVAL;
101
102 if (efi.mps != EFI_INVALID_TABLE_ADDR)
103 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
104 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
105 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
106 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
107 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
108 /*
109 * If both SMBIOS and SMBIOS3 entry points are implemented, the
110 * SMBIOS3 entry point shall be preferred, so we list it first to
111 * let applications stop parsing after the first match.
112 */
113 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
114 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
115 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
116 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
117 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
118 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
119 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
120 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
121 if (efi.uga != EFI_INVALID_TABLE_ADDR)
122 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
123
124 return str - buf;
125}
126
127static struct kobj_attribute efi_attr_systab =
128 __ATTR(systab, 0400, systab_show, NULL);
129
130#define EFI_FIELD(var) efi.var
131
132#define EFI_ATTR_SHOW(name) \
133static ssize_t name##_show(struct kobject *kobj, \
134 struct kobj_attribute *attr, char *buf) \
135{ \
136 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
137}
138
139EFI_ATTR_SHOW(fw_vendor);
140EFI_ATTR_SHOW(runtime);
141EFI_ATTR_SHOW(config_table);
142
143static ssize_t fw_platform_size_show(struct kobject *kobj,
144 struct kobj_attribute *attr, char *buf)
145{
146 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
147}
148
149static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
150static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
151static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
152static struct kobj_attribute efi_attr_fw_platform_size =
153 __ATTR_RO(fw_platform_size);
154
155static struct attribute *efi_subsys_attrs[] = {
156 &efi_attr_systab.attr,
157 &efi_attr_fw_vendor.attr,
158 &efi_attr_runtime.attr,
159 &efi_attr_config_table.attr,
160 &efi_attr_fw_platform_size.attr,
161 NULL,
162};
163
164static umode_t efi_attr_is_visible(struct kobject *kobj,
165 struct attribute *attr, int n)
166{
167 if (attr == &efi_attr_fw_vendor.attr) {
168 if (efi_enabled(EFI_PARAVIRT) ||
169 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
170 return 0;
171 } else if (attr == &efi_attr_runtime.attr) {
172 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
173 return 0;
174 } else if (attr == &efi_attr_config_table.attr) {
175 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
176 return 0;
177 }
178
179 return attr->mode;
180}
181
182static 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.set_variable = efi.set_variable;
194 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
195 generic_ops.get_next_variable = efi.get_next_variable;
196 generic_ops.query_variable_store = efi_query_variable_store;
197
198 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
199}
200
201static void generic_ops_unregister(void)
202{
203 efivars_unregister(&generic_efivars);
204}
205
206#if IS_ENABLED(CONFIG_ACPI)
207#define EFIVAR_SSDT_NAME_MAX 16
208static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
209static int __init efivar_ssdt_setup(char *str)
210{
211 if (strlen(str) < sizeof(efivar_ssdt))
212 memcpy(efivar_ssdt, str, strlen(str));
213 else
214 pr_warn("efivar_ssdt: name too long: %s\n", str);
215 return 0;
216}
217__setup("efivar_ssdt=", efivar_ssdt_setup);
218
219static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
220 unsigned long name_size, void *data)
221{
222 struct efivar_entry *entry;
223 struct list_head *list = data;
224 char utf8_name[EFIVAR_SSDT_NAME_MAX];
225 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
226
227 ucs2_as_utf8(utf8_name, name, limit - 1);
228 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
229 return 0;
230
231 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
232 if (!entry)
233 return 0;
234
235 memcpy(entry->var.VariableName, name, name_size);
236 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
237
238 efivar_entry_add(entry, list);
239
240 return 0;
241}
242
243static __init int efivar_ssdt_load(void)
244{
245 LIST_HEAD(entries);
246 struct efivar_entry *entry, *aux;
247 unsigned long size;
248 void *data;
249 int ret;
250
251 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
252
253 list_for_each_entry_safe(entry, aux, &entries, list) {
254 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
255 &entry->var.VendorGuid);
256
257 list_del(&entry->list);
258
259 ret = efivar_entry_size(entry, &size);
260 if (ret) {
261 pr_err("failed to get var size\n");
262 goto free_entry;
263 }
264
265 data = kmalloc(size, GFP_KERNEL);
266 if (!data) {
267 ret = -ENOMEM;
268 goto free_entry;
269 }
270
271 ret = efivar_entry_get(entry, NULL, &size, data);
272 if (ret) {
273 pr_err("failed to get var data\n");
274 goto free_data;
275 }
276
277 ret = acpi_load_table(data);
278 if (ret) {
279 pr_err("failed to load table: %d\n", ret);
280 goto free_data;
281 }
282
283 goto free_entry;
284
285free_data:
286 kfree(data);
287
288free_entry:
289 kfree(entry);
290 }
291
292 return ret;
293}
294#else
295static inline int efivar_ssdt_load(void) { return 0; }
296#endif
297
298/*
299 * We register the efi subsystem with the firmware subsystem and the
300 * efivars subsystem with the efi subsystem, if the system was booted with
301 * EFI.
302 */
303static int __init efisubsys_init(void)
304{
305 int error;
306
307 if (!efi_enabled(EFI_BOOT))
308 return 0;
309
310 /* We register the efi directory at /sys/firmware/efi */
311 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
312 if (!efi_kobj) {
313 pr_err("efi: Firmware registration failed.\n");
314 return -ENOMEM;
315 }
316
317 error = generic_ops_register();
318 if (error)
319 goto err_put;
320
321 if (efi_enabled(EFI_RUNTIME_SERVICES))
322 efivar_ssdt_load();
323
324 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
325 if (error) {
326 pr_err("efi: Sysfs attribute export failed with error %d.\n",
327 error);
328 goto err_unregister;
329 }
330
331 error = efi_runtime_map_init(efi_kobj);
332 if (error)
333 goto err_remove_group;
334
335 /* and the standard mountpoint for efivarfs */
336 error = sysfs_create_mount_point(efi_kobj, "efivars");
337 if (error) {
338 pr_err("efivars: Subsystem registration failed.\n");
339 goto err_remove_group;
340 }
341
342 return 0;
343
344err_remove_group:
345 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
346err_unregister:
347 generic_ops_unregister();
348err_put:
349 kobject_put(efi_kobj);
350 return error;
351}
352
353subsys_initcall(efisubsys_init);
354
355/*
356 * Find the efi memory descriptor for a given physical address. Given a
357 * physical address, determine if it exists within an EFI Memory Map entry,
358 * and if so, populate the supplied memory descriptor with the appropriate
359 * data.
360 */
361int __init efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
362{
363 efi_memory_desc_t *md;
364
365 if (!efi_enabled(EFI_MEMMAP)) {
366 pr_err_once("EFI_MEMMAP is not enabled.\n");
367 return -EINVAL;
368 }
369
370 if (!out_md) {
371 pr_err_once("out_md is null.\n");
372 return -EINVAL;
373 }
374
375 for_each_efi_memory_desc(md) {
376 u64 size;
377 u64 end;
378
379 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
380 md->type != EFI_BOOT_SERVICES_DATA &&
381 md->type != EFI_RUNTIME_SERVICES_DATA) {
382 continue;
383 }
384
385 size = md->num_pages << EFI_PAGE_SHIFT;
386 end = md->phys_addr + size;
387 if (phys_addr >= md->phys_addr && phys_addr < end) {
388 memcpy(out_md, md, sizeof(*out_md));
389 return 0;
390 }
391 }
392 pr_err_once("requested map not found.\n");
393 return -ENOENT;
394}
395
396/*
397 * Calculate the highest address of an efi memory descriptor.
398 */
399u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
400{
401 u64 size = md->num_pages << EFI_PAGE_SHIFT;
402 u64 end = md->phys_addr + size;
403 return end;
404}
405
406void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
407
408/**
409 * efi_mem_reserve - Reserve an EFI memory region
410 * @addr: Physical address to reserve
411 * @size: Size of reservation
412 *
413 * Mark a region as reserved from general kernel allocation and
414 * prevent it being released by efi_free_boot_services().
415 *
416 * This function should be called drivers once they've parsed EFI
417 * configuration tables to figure out where their data lives, e.g.
418 * efi_esrt_init().
419 */
420void __init efi_mem_reserve(phys_addr_t addr, u64 size)
421{
422 if (!memblock_is_region_reserved(addr, size))
423 memblock_reserve(addr, size);
424
425 /*
426 * Some architectures (x86) reserve all boot services ranges
427 * until efi_free_boot_services() because of buggy firmware
428 * implementations. This means the above memblock_reserve() is
429 * superfluous on x86 and instead what it needs to do is
430 * ensure the @start, @size is not freed.
431 */
432 efi_arch_mem_reserve(addr, size);
433}
434
435static __initdata efi_config_table_type_t common_tables[] = {
436 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
437 {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
438 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
439 {MPS_TABLE_GUID, "MPS", &efi.mps},
440 {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
441 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
442 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
443 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
444 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
445 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
446 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
447 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
448 {NULL_GUID, NULL, NULL},
449};
450
451static __init int match_config_table(efi_guid_t *guid,
452 unsigned long table,
453 efi_config_table_type_t *table_types)
454{
455 int i;
456
457 if (table_types) {
458 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
459 if (!efi_guidcmp(*guid, table_types[i].guid)) {
460 *(table_types[i].ptr) = table;
461 if (table_types[i].name)
462 pr_cont(" %s=0x%lx ",
463 table_types[i].name, table);
464 return 1;
465 }
466 }
467 }
468
469 return 0;
470}
471
472int __init efi_config_parse_tables(void *config_tables, int count, int sz,
473 efi_config_table_type_t *arch_tables)
474{
475 void *tablep;
476 int i;
477
478 tablep = config_tables;
479 pr_info("");
480 for (i = 0; i < count; i++) {
481 efi_guid_t guid;
482 unsigned long table;
483
484 if (efi_enabled(EFI_64BIT)) {
485 u64 table64;
486 guid = ((efi_config_table_64_t *)tablep)->guid;
487 table64 = ((efi_config_table_64_t *)tablep)->table;
488 table = table64;
489#ifndef CONFIG_64BIT
490 if (table64 >> 32) {
491 pr_cont("\n");
492 pr_err("Table located above 4GB, disabling EFI.\n");
493 return -EINVAL;
494 }
495#endif
496 } else {
497 guid = ((efi_config_table_32_t *)tablep)->guid;
498 table = ((efi_config_table_32_t *)tablep)->table;
499 }
500
501 if (!match_config_table(&guid, table, common_tables))
502 match_config_table(&guid, table, arch_tables);
503
504 tablep += sz;
505 }
506 pr_cont("\n");
507 set_bit(EFI_CONFIG_TABLES, &efi.flags);
508
509 if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
510 struct linux_efi_random_seed *seed;
511 u32 size = 0;
512
513 seed = early_memremap(efi.rng_seed, sizeof(*seed));
514 if (seed != NULL) {
515 size = seed->size;
516 early_memunmap(seed, sizeof(*seed));
517 } else {
518 pr_err("Could not map UEFI random seed!\n");
519 }
520 if (size > 0) {
521 seed = early_memremap(efi.rng_seed,
522 sizeof(*seed) + size);
523 if (seed != NULL) {
524 add_device_randomness(seed->bits, seed->size);
525 early_memunmap(seed, sizeof(*seed) + size);
526 } else {
527 pr_err("Could not map UEFI random seed!\n");
528 }
529 }
530 }
531
532 /* Parse the EFI Properties table if it exists */
533 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
534 efi_properties_table_t *tbl;
535
536 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
537 if (tbl == NULL) {
538 pr_err("Could not map Properties table!\n");
539 return -ENOMEM;
540 }
541
542 if (tbl->memory_protection_attribute &
543 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
544 set_bit(EFI_NX_PE_DATA, &efi.flags);
545
546 early_memunmap(tbl, sizeof(*tbl));
547 }
548
549 return 0;
550}
551
552int __init efi_config_init(efi_config_table_type_t *arch_tables)
553{
554 void *config_tables;
555 int sz, ret;
556
557 if (efi_enabled(EFI_64BIT))
558 sz = sizeof(efi_config_table_64_t);
559 else
560 sz = sizeof(efi_config_table_32_t);
561
562 /*
563 * Let's see what config tables the firmware passed to us.
564 */
565 config_tables = early_memremap(efi.systab->tables,
566 efi.systab->nr_tables * sz);
567 if (config_tables == NULL) {
568 pr_err("Could not map Configuration table!\n");
569 return -ENOMEM;
570 }
571
572 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
573 arch_tables);
574
575 early_memunmap(config_tables, efi.systab->nr_tables * sz);
576 return ret;
577}
578
579#ifdef CONFIG_EFI_VARS_MODULE
580static int __init efi_load_efivars(void)
581{
582 struct platform_device *pdev;
583
584 if (!efi_enabled(EFI_RUNTIME_SERVICES))
585 return 0;
586
587 pdev = platform_device_register_simple("efivars", 0, NULL, 0);
588 return IS_ERR(pdev) ? PTR_ERR(pdev) : 0;
589}
590device_initcall(efi_load_efivars);
591#endif
592
593#ifdef CONFIG_EFI_PARAMS_FROM_FDT
594
595#define UEFI_PARAM(name, prop, field) \
596 { \
597 { name }, \
598 { prop }, \
599 offsetof(struct efi_fdt_params, field), \
600 FIELD_SIZEOF(struct efi_fdt_params, field) \
601 }
602
603struct params {
604 const char name[32];
605 const char propname[32];
606 int offset;
607 int size;
608};
609
610static __initdata struct params fdt_params[] = {
611 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
612 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
613 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
614 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
615 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
616};
617
618static __initdata struct params xen_fdt_params[] = {
619 UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
620 UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
621 UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
622 UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
623 UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
624};
625
626#define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
627
628static __initdata struct {
629 const char *uname;
630 const char *subnode;
631 struct params *params;
632} dt_params[] = {
633 { "hypervisor", "uefi", xen_fdt_params },
634 { "chosen", NULL, fdt_params },
635};
636
637struct param_info {
638 int found;
639 void *params;
640 const char *missing;
641};
642
643static int __init __find_uefi_params(unsigned long node,
644 struct param_info *info,
645 struct params *params)
646{
647 const void *prop;
648 void *dest;
649 u64 val;
650 int i, len;
651
652 for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
653 prop = of_get_flat_dt_prop(node, params[i].propname, &len);
654 if (!prop) {
655 info->missing = params[i].name;
656 return 0;
657 }
658
659 dest = info->params + params[i].offset;
660 info->found++;
661
662 val = of_read_number(prop, len / sizeof(u32));
663
664 if (params[i].size == sizeof(u32))
665 *(u32 *)dest = val;
666 else
667 *(u64 *)dest = val;
668
669 if (efi_enabled(EFI_DBG))
670 pr_info(" %s: 0x%0*llx\n", params[i].name,
671 params[i].size * 2, val);
672 }
673
674 return 1;
675}
676
677static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
678 int depth, void *data)
679{
680 struct param_info *info = data;
681 int i;
682
683 for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
684 const char *subnode = dt_params[i].subnode;
685
686 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
687 info->missing = dt_params[i].params[0].name;
688 continue;
689 }
690
691 if (subnode) {
692 int err = of_get_flat_dt_subnode_by_name(node, subnode);
693
694 if (err < 0)
695 return 0;
696
697 node = err;
698 }
699
700 return __find_uefi_params(node, info, dt_params[i].params);
701 }
702
703 return 0;
704}
705
706int __init efi_get_fdt_params(struct efi_fdt_params *params)
707{
708 struct param_info info;
709 int ret;
710
711 pr_info("Getting EFI parameters from FDT:\n");
712
713 info.found = 0;
714 info.params = params;
715
716 ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
717 if (!info.found)
718 pr_info("UEFI not found.\n");
719 else if (!ret)
720 pr_err("Can't find '%s' in device tree!\n",
721 info.missing);
722
723 return ret;
724}
725#endif /* CONFIG_EFI_PARAMS_FROM_FDT */
726
727static __initdata char memory_type_name[][20] = {
728 "Reserved",
729 "Loader Code",
730 "Loader Data",
731 "Boot Code",
732 "Boot Data",
733 "Runtime Code",
734 "Runtime Data",
735 "Conventional Memory",
736 "Unusable Memory",
737 "ACPI Reclaim Memory",
738 "ACPI Memory NVS",
739 "Memory Mapped I/O",
740 "MMIO Port Space",
741 "PAL Code",
742 "Persistent Memory",
743};
744
745char * __init efi_md_typeattr_format(char *buf, size_t size,
746 const efi_memory_desc_t *md)
747{
748 char *pos;
749 int type_len;
750 u64 attr;
751
752 pos = buf;
753 if (md->type >= ARRAY_SIZE(memory_type_name))
754 type_len = snprintf(pos, size, "[type=%u", md->type);
755 else
756 type_len = snprintf(pos, size, "[%-*s",
757 (int)(sizeof(memory_type_name[0]) - 1),
758 memory_type_name[md->type]);
759 if (type_len >= size)
760 return buf;
761
762 pos += type_len;
763 size -= type_len;
764
765 attr = md->attribute;
766 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
767 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
768 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
769 EFI_MEMORY_NV |
770 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
771 snprintf(pos, size, "|attr=0x%016llx]",
772 (unsigned long long)attr);
773 else
774 snprintf(pos, size,
775 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
776 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
777 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
778 attr & EFI_MEMORY_NV ? "NV" : "",
779 attr & EFI_MEMORY_XP ? "XP" : "",
780 attr & EFI_MEMORY_RP ? "RP" : "",
781 attr & EFI_MEMORY_WP ? "WP" : "",
782 attr & EFI_MEMORY_RO ? "RO" : "",
783 attr & EFI_MEMORY_UCE ? "UCE" : "",
784 attr & EFI_MEMORY_WB ? "WB" : "",
785 attr & EFI_MEMORY_WT ? "WT" : "",
786 attr & EFI_MEMORY_WC ? "WC" : "",
787 attr & EFI_MEMORY_UC ? "UC" : "");
788 return buf;
789}
790
791/*
792 * efi_mem_attributes - lookup memmap attributes for physical address
793 * @phys_addr: the physical address to lookup
794 *
795 * Search in the EFI memory map for the region covering
796 * @phys_addr. Returns the EFI memory attributes if the region
797 * was found in the memory map, 0 otherwise.
798 *
799 * Despite being marked __weak, most architectures should *not*
800 * override this function. It is __weak solely for the benefit
801 * of ia64 which has a funky EFI memory map that doesn't work
802 * the same way as other architectures.
803 */
804u64 __weak efi_mem_attributes(unsigned long phys_addr)
805{
806 efi_memory_desc_t *md;
807
808 if (!efi_enabled(EFI_MEMMAP))
809 return 0;
810
811 for_each_efi_memory_desc(md) {
812 if ((md->phys_addr <= phys_addr) &&
813 (phys_addr < (md->phys_addr +
814 (md->num_pages << EFI_PAGE_SHIFT))))
815 return md->attribute;
816 }
817 return 0;
818}
819
820int efi_status_to_err(efi_status_t status)
821{
822 int err;
823
824 switch (status) {
825 case EFI_SUCCESS:
826 err = 0;
827 break;
828 case EFI_INVALID_PARAMETER:
829 err = -EINVAL;
830 break;
831 case EFI_OUT_OF_RESOURCES:
832 err = -ENOSPC;
833 break;
834 case EFI_DEVICE_ERROR:
835 err = -EIO;
836 break;
837 case EFI_WRITE_PROTECTED:
838 err = -EROFS;
839 break;
840 case EFI_SECURITY_VIOLATION:
841 err = -EACCES;
842 break;
843 case EFI_NOT_FOUND:
844 err = -ENOENT;
845 break;
846 case EFI_ABORTED:
847 err = -EINTR;
848 break;
849 default:
850 err = -EINVAL;
851 }
852
853 return err;
854}
855
856#ifdef CONFIG_KEXEC
857static int update_efi_random_seed(struct notifier_block *nb,
858 unsigned long code, void *unused)
859{
860 struct linux_efi_random_seed *seed;
861 u32 size = 0;
862
863 if (!kexec_in_progress)
864 return NOTIFY_DONE;
865
866 seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
867 if (seed != NULL) {
868 size = min(seed->size, 32U);
869 memunmap(seed);
870 } else {
871 pr_err("Could not map UEFI random seed!\n");
872 }
873 if (size > 0) {
874 seed = memremap(efi.rng_seed, sizeof(*seed) + size,
875 MEMREMAP_WB);
876 if (seed != NULL) {
877 seed->size = size;
878 get_random_bytes(seed->bits, seed->size);
879 memunmap(seed);
880 } else {
881 pr_err("Could not map UEFI random seed!\n");
882 }
883 }
884 return NOTIFY_DONE;
885}
886
887static struct notifier_block efi_random_seed_nb = {
888 .notifier_call = update_efi_random_seed,
889};
890
891static int register_update_efi_random_seed(void)
892{
893 if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
894 return 0;
895 return register_reboot_notifier(&efi_random_seed_nb);
896}
897late_initcall(register_update_efi_random_seed);
898#endif