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