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