1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Helper functions used by the EFI stub on multiple
4 * architectures. This should be #included by the EFI stub
5 * implementation files.
6 *
7 * Copyright 2011 Intel Corporation; author Matt Fleming
8 */
9
10 #include <linux/stdarg.h>
11
12 #include <linux/ctype.h>
13 #include <linux/efi.h>
14 #include <linux/kernel.h>
15 #include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
16 #include <asm/efi.h>
17 #include <asm/setup.h>
18
19 #include "efistub.h"
20
21 bool efi_nochunk;
22 bool efi_nokaslr = !IS_ENABLED(CONFIG_RANDOMIZE_BASE);
23 int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
24 bool efi_novamap;
25
26 static bool efi_noinitrd;
27 static bool efi_nosoftreserve;
28 static bool efi_disable_pci_dma = IS_ENABLED(CONFIG_EFI_DISABLE_PCI_DMA);
29
__efi_soft_reserve_enabled(void)30 bool __pure __efi_soft_reserve_enabled(void)
31 {
32 return !efi_nosoftreserve;
33 }
34
35 /**
36 * efi_char16_puts() - Write a UCS-2 encoded string to the console
37 * @str: UCS-2 encoded string
38 */
efi_char16_puts(efi_char16_t * str)39 void efi_char16_puts(efi_char16_t *str)
40 {
41 efi_call_proto(efi_table_attr(efi_system_table, con_out),
42 output_string, str);
43 }
44
45 static
utf8_to_utf32(const u8 ** s8)46 u32 utf8_to_utf32(const u8 **s8)
47 {
48 u32 c32;
49 u8 c0, cx;
50 size_t clen, i;
51
52 c0 = cx = *(*s8)++;
53 /*
54 * The position of the most-significant 0 bit gives us the length of
55 * a multi-octet encoding.
56 */
57 for (clen = 0; cx & 0x80; ++clen)
58 cx <<= 1;
59 /*
60 * If the 0 bit is in position 8, this is a valid single-octet
61 * encoding. If the 0 bit is in position 7 or positions 1-3, the
62 * encoding is invalid.
63 * In either case, we just return the first octet.
64 */
65 if (clen < 2 || clen > 4)
66 return c0;
67 /* Get the bits from the first octet. */
68 c32 = cx >> clen--;
69 for (i = 0; i < clen; ++i) {
70 /* Trailing octets must have 10 in most significant bits. */
71 cx = (*s8)[i] ^ 0x80;
72 if (cx & 0xc0)
73 return c0;
74 c32 = (c32 << 6) | cx;
75 }
76 /*
77 * Check for validity:
78 * - The character must be in the Unicode range.
79 * - It must not be a surrogate.
80 * - It must be encoded using the correct number of octets.
81 */
82 if (c32 > 0x10ffff ||
83 (c32 & 0xf800) == 0xd800 ||
84 clen != (c32 >= 0x80) + (c32 >= 0x800) + (c32 >= 0x10000))
85 return c0;
86 *s8 += clen;
87 return c32;
88 }
89
90 /**
91 * efi_puts() - Write a UTF-8 encoded string to the console
92 * @str: UTF-8 encoded string
93 */
efi_puts(const char * str)94 void efi_puts(const char *str)
95 {
96 efi_char16_t buf[128];
97 size_t pos = 0, lim = ARRAY_SIZE(buf);
98 const u8 *s8 = (const u8 *)str;
99 u32 c32;
100
101 while (*s8) {
102 if (*s8 == '\n')
103 buf[pos++] = L'\r';
104 c32 = utf8_to_utf32(&s8);
105 if (c32 < 0x10000) {
106 /* Characters in plane 0 use a single word. */
107 buf[pos++] = c32;
108 } else {
109 /*
110 * Characters in other planes encode into a surrogate
111 * pair.
112 */
113 buf[pos++] = (0xd800 - (0x10000 >> 10)) + (c32 >> 10);
114 buf[pos++] = 0xdc00 + (c32 & 0x3ff);
115 }
116 if (*s8 == '\0' || pos >= lim - 2) {
117 buf[pos] = L'\0';
118 efi_char16_puts(buf);
119 pos = 0;
120 }
121 }
122 }
123
124 /**
125 * efi_printk() - Print a kernel message
126 * @fmt: format string
127 *
128 * The first letter of the format string is used to determine the logging level
129 * of the message. If the level is less then the current EFI logging level, the
130 * message is suppressed. The message will be truncated to 255 bytes.
131 *
132 * Return: number of printed characters
133 */
efi_printk(const char * fmt,...)134 int efi_printk(const char *fmt, ...)
135 {
136 char printf_buf[256];
137 va_list args;
138 int printed;
139 int loglevel = printk_get_level(fmt);
140
141 switch (loglevel) {
142 case '0' ... '9':
143 loglevel -= '0';
144 break;
145 default:
146 /*
147 * Use loglevel -1 for cases where we just want to print to
148 * the screen.
149 */
150 loglevel = -1;
151 break;
152 }
153
154 if (loglevel >= efi_loglevel)
155 return 0;
156
157 if (loglevel >= 0)
158 efi_puts("EFI stub: ");
159
160 fmt = printk_skip_level(fmt);
161
162 va_start(args, fmt);
163 printed = vsnprintf(printf_buf, sizeof(printf_buf), fmt, args);
164 va_end(args);
165
166 efi_puts(printf_buf);
167 if (printed >= sizeof(printf_buf)) {
168 efi_puts("[Message truncated]\n");
169 return -1;
170 }
171
172 return printed;
173 }
174
175 /**
176 * efi_parse_options() - Parse EFI command line options
177 * @cmdline: kernel command line
178 *
179 * Parse the ASCII string @cmdline for EFI options, denoted by the efi=
180 * option, e.g. efi=nochunk.
181 *
182 * It should be noted that efi= is parsed in two very different
183 * environments, first in the early boot environment of the EFI boot
184 * stub, and subsequently during the kernel boot.
185 *
186 * Return: status code
187 */
efi_parse_options(char const * cmdline)188 efi_status_t efi_parse_options(char const *cmdline)
189 {
190 size_t len;
191 efi_status_t status;
192 char *str, *buf;
193
194 if (!cmdline)
195 return EFI_SUCCESS;
196
197 len = strnlen(cmdline, COMMAND_LINE_SIZE - 1) + 1;
198 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, len, (void **)&buf);
199 if (status != EFI_SUCCESS)
200 return status;
201
202 memcpy(buf, cmdline, len - 1);
203 buf[len - 1] = '\0';
204 str = skip_spaces(buf);
205
206 while (*str) {
207 char *param, *val;
208
209 str = next_arg(str, ¶m, &val);
210 if (!val && !strcmp(param, "--"))
211 break;
212
213 if (!strcmp(param, "nokaslr")) {
214 efi_nokaslr = true;
215 } else if (!strcmp(param, "quiet")) {
216 efi_loglevel = CONSOLE_LOGLEVEL_QUIET;
217 } else if (!strcmp(param, "noinitrd")) {
218 efi_noinitrd = true;
219 } else if (!strcmp(param, "efi") && val) {
220 efi_nochunk = parse_option_str(val, "nochunk");
221 efi_novamap = parse_option_str(val, "novamap");
222
223 efi_nosoftreserve = IS_ENABLED(CONFIG_EFI_SOFT_RESERVE) &&
224 parse_option_str(val, "nosoftreserve");
225
226 if (parse_option_str(val, "disable_early_pci_dma"))
227 efi_disable_pci_dma = true;
228 if (parse_option_str(val, "no_disable_early_pci_dma"))
229 efi_disable_pci_dma = false;
230 if (parse_option_str(val, "debug"))
231 efi_loglevel = CONSOLE_LOGLEVEL_DEBUG;
232 } else if (!strcmp(param, "video") &&
233 val && strstarts(val, "efifb:")) {
234 efi_parse_option_graphics(val + strlen("efifb:"));
235 }
236 }
237 efi_bs_call(free_pool, buf);
238 return EFI_SUCCESS;
239 }
240
241 /*
242 * The EFI_LOAD_OPTION descriptor has the following layout:
243 * u32 Attributes;
244 * u16 FilePathListLength;
245 * u16 Description[];
246 * efi_device_path_protocol_t FilePathList[];
247 * u8 OptionalData[];
248 *
249 * This function validates and unpacks the variable-size data fields.
250 */
251 static
efi_load_option_unpack(efi_load_option_unpacked_t * dest,const efi_load_option_t * src,size_t size)252 bool efi_load_option_unpack(efi_load_option_unpacked_t *dest,
253 const efi_load_option_t *src, size_t size)
254 {
255 const void *pos;
256 u16 c;
257 efi_device_path_protocol_t header;
258 const efi_char16_t *description;
259 const efi_device_path_protocol_t *file_path_list;
260
261 if (size < offsetof(efi_load_option_t, variable_data))
262 return false;
263 pos = src->variable_data;
264 size -= offsetof(efi_load_option_t, variable_data);
265
266 if ((src->attributes & ~EFI_LOAD_OPTION_MASK) != 0)
267 return false;
268
269 /* Scan description. */
270 description = pos;
271 do {
272 if (size < sizeof(c))
273 return false;
274 c = *(const u16 *)pos;
275 pos += sizeof(c);
276 size -= sizeof(c);
277 } while (c != L'\0');
278
279 /* Scan file_path_list. */
280 file_path_list = pos;
281 do {
282 if (size < sizeof(header))
283 return false;
284 header = *(const efi_device_path_protocol_t *)pos;
285 if (header.length < sizeof(header))
286 return false;
287 if (size < header.length)
288 return false;
289 pos += header.length;
290 size -= header.length;
291 } while ((header.type != EFI_DEV_END_PATH && header.type != EFI_DEV_END_PATH2) ||
292 (header.sub_type != EFI_DEV_END_ENTIRE));
293 if (pos != (const void *)file_path_list + src->file_path_list_length)
294 return false;
295
296 dest->attributes = src->attributes;
297 dest->file_path_list_length = src->file_path_list_length;
298 dest->description = description;
299 dest->file_path_list = file_path_list;
300 dest->optional_data_size = size;
301 dest->optional_data = size ? pos : NULL;
302
303 return true;
304 }
305
306 /*
307 * At least some versions of Dell firmware pass the entire contents of the
308 * Boot#### variable, i.e. the EFI_LOAD_OPTION descriptor, rather than just the
309 * OptionalData field.
310 *
311 * Detect this case and extract OptionalData.
312 */
efi_apply_loadoptions_quirk(const void ** load_options,int * load_options_size)313 void efi_apply_loadoptions_quirk(const void **load_options, int *load_options_size)
314 {
315 const efi_load_option_t *load_option = *load_options;
316 efi_load_option_unpacked_t load_option_unpacked;
317
318 if (!IS_ENABLED(CONFIG_X86))
319 return;
320 if (!load_option)
321 return;
322 if (*load_options_size < sizeof(*load_option))
323 return;
324 if ((load_option->attributes & ~EFI_LOAD_OPTION_BOOT_MASK) != 0)
325 return;
326
327 if (!efi_load_option_unpack(&load_option_unpacked, load_option, *load_options_size))
328 return;
329
330 efi_warn_once(FW_BUG "LoadOptions is an EFI_LOAD_OPTION descriptor\n");
331 efi_warn_once(FW_BUG "Using OptionalData as a workaround\n");
332
333 *load_options = load_option_unpacked.optional_data;
334 *load_options_size = load_option_unpacked.optional_data_size;
335 }
336
337 /*
338 * Convert the unicode UEFI command line to ASCII to pass to kernel.
339 * Size of memory allocated return in *cmd_line_len.
340 * Returns NULL on error.
341 */
efi_convert_cmdline(efi_loaded_image_t * image,int * cmd_line_len)342 char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len)
343 {
344 const u16 *s2;
345 unsigned long cmdline_addr = 0;
346 int options_chars = efi_table_attr(image, load_options_size);
347 const u16 *options = efi_table_attr(image, load_options);
348 int options_bytes = 0, safe_options_bytes = 0; /* UTF-8 bytes */
349 bool in_quote = false;
350 efi_status_t status;
351
352 efi_apply_loadoptions_quirk((const void **)&options, &options_chars);
353 options_chars /= sizeof(*options);
354
355 if (options) {
356 s2 = options;
357 while (options_bytes < COMMAND_LINE_SIZE && options_chars--) {
358 u16 c = *s2++;
359
360 if (c < 0x80) {
361 if (c == L'\0' || c == L'\n')
362 break;
363 if (c == L'"')
364 in_quote = !in_quote;
365 else if (!in_quote && isspace((char)c))
366 safe_options_bytes = options_bytes;
367
368 options_bytes++;
369 continue;
370 }
371
372 /*
373 * Get the number of UTF-8 bytes corresponding to a
374 * UTF-16 character.
375 * The first part handles everything in the BMP.
376 */
377 options_bytes += 2 + (c >= 0x800);
378 /*
379 * Add one more byte for valid surrogate pairs. Invalid
380 * surrogates will be replaced with 0xfffd and take up
381 * only 3 bytes.
382 */
383 if ((c & 0xfc00) == 0xd800) {
384 /*
385 * If the very last word is a high surrogate,
386 * we must ignore it since we can't access the
387 * low surrogate.
388 */
389 if (!options_chars) {
390 options_bytes -= 3;
391 } else if ((*s2 & 0xfc00) == 0xdc00) {
392 options_bytes++;
393 options_chars--;
394 s2++;
395 }
396 }
397 }
398 if (options_bytes >= COMMAND_LINE_SIZE) {
399 options_bytes = safe_options_bytes;
400 efi_err("Command line is too long: truncated to %d bytes\n",
401 options_bytes);
402 }
403 }
404
405 options_bytes++; /* NUL termination */
406
407 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, options_bytes,
408 (void **)&cmdline_addr);
409 if (status != EFI_SUCCESS)
410 return NULL;
411
412 snprintf((char *)cmdline_addr, options_bytes, "%.*ls",
413 options_bytes - 1, options);
414
415 *cmd_line_len = options_bytes;
416 return (char *)cmdline_addr;
417 }
418
419 /**
420 * efi_exit_boot_services() - Exit boot services
421 * @handle: handle of the exiting image
422 * @map: pointer to receive the memory map
423 * @priv: argument to be passed to @priv_func
424 * @priv_func: function to process the memory map before exiting boot services
425 *
426 * Handle calling ExitBootServices according to the requirements set out by the
427 * spec. Obtains the current memory map, and returns that info after calling
428 * ExitBootServices. The client must specify a function to perform any
429 * processing of the memory map data prior to ExitBootServices. A client
430 * specific structure may be passed to the function via priv. The client
431 * function may be called multiple times.
432 *
433 * Return: status code
434 */
efi_exit_boot_services(void * handle,struct efi_boot_memmap * map,void * priv,efi_exit_boot_map_processing priv_func)435 efi_status_t efi_exit_boot_services(void *handle,
436 struct efi_boot_memmap *map,
437 void *priv,
438 efi_exit_boot_map_processing priv_func)
439 {
440 efi_status_t status;
441
442 status = efi_get_memory_map(map);
443
444 if (status != EFI_SUCCESS)
445 goto fail;
446
447 status = priv_func(map, priv);
448 if (status != EFI_SUCCESS)
449 goto free_map;
450
451 if (efi_disable_pci_dma)
452 efi_pci_disable_bridge_busmaster();
453
454 status = efi_bs_call(exit_boot_services, handle, *map->key_ptr);
455
456 if (status == EFI_INVALID_PARAMETER) {
457 /*
458 * The memory map changed between efi_get_memory_map() and
459 * exit_boot_services(). Per the UEFI Spec v2.6, Section 6.4:
460 * EFI_BOOT_SERVICES.ExitBootServices we need to get the
461 * updated map, and try again. The spec implies one retry
462 * should be sufficent, which is confirmed against the EDK2
463 * implementation. Per the spec, we can only invoke
464 * get_memory_map() and exit_boot_services() - we cannot alloc
465 * so efi_get_memory_map() cannot be used, and we must reuse
466 * the buffer. For all practical purposes, the headroom in the
467 * buffer should account for any changes in the map so the call
468 * to get_memory_map() is expected to succeed here.
469 */
470 *map->map_size = *map->buff_size;
471 status = efi_bs_call(get_memory_map,
472 map->map_size,
473 *map->map,
474 map->key_ptr,
475 map->desc_size,
476 map->desc_ver);
477
478 /* exit_boot_services() was called, thus cannot free */
479 if (status != EFI_SUCCESS)
480 goto fail;
481
482 status = priv_func(map, priv);
483 /* exit_boot_services() was called, thus cannot free */
484 if (status != EFI_SUCCESS)
485 goto fail;
486
487 status = efi_bs_call(exit_boot_services, handle, *map->key_ptr);
488 }
489
490 /* exit_boot_services() was called, thus cannot free */
491 if (status != EFI_SUCCESS)
492 goto fail;
493
494 return EFI_SUCCESS;
495
496 free_map:
497 efi_bs_call(free_pool, *map->map);
498 fail:
499 return status;
500 }
501
502 /**
503 * get_efi_config_table() - retrieve UEFI configuration table
504 * @guid: GUID of the configuration table to be retrieved
505 * Return: pointer to the configuration table or NULL
506 */
get_efi_config_table(efi_guid_t guid)507 void *get_efi_config_table(efi_guid_t guid)
508 {
509 unsigned long tables = efi_table_attr(efi_system_table, tables);
510 int nr_tables = efi_table_attr(efi_system_table, nr_tables);
511 int i;
512
513 for (i = 0; i < nr_tables; i++) {
514 efi_config_table_t *t = (void *)tables;
515
516 if (efi_guidcmp(t->guid, guid) == 0)
517 return efi_table_attr(t, table);
518
519 tables += efi_is_native() ? sizeof(efi_config_table_t)
520 : sizeof(efi_config_table_32_t);
521 }
522 return NULL;
523 }
524
525 /*
526 * The LINUX_EFI_INITRD_MEDIA_GUID vendor media device path below provides a way
527 * for the firmware or bootloader to expose the initrd data directly to the stub
528 * via the trivial LoadFile2 protocol, which is defined in the UEFI spec, and is
529 * very easy to implement. It is a simple Linux initrd specific conduit between
530 * kernel and firmware, allowing us to put the EFI stub (being part of the
531 * kernel) in charge of where and when to load the initrd, while leaving it up
532 * to the firmware to decide whether it needs to expose its filesystem hierarchy
533 * via EFI protocols.
534 */
535 static const struct {
536 struct efi_vendor_dev_path vendor;
537 struct efi_generic_dev_path end;
538 } __packed initrd_dev_path = {
539 {
540 {
541 EFI_DEV_MEDIA,
542 EFI_DEV_MEDIA_VENDOR,
543 sizeof(struct efi_vendor_dev_path),
544 },
545 LINUX_EFI_INITRD_MEDIA_GUID
546 }, {
547 EFI_DEV_END_PATH,
548 EFI_DEV_END_ENTIRE,
549 sizeof(struct efi_generic_dev_path)
550 }
551 };
552
553 /**
554 * efi_load_initrd_dev_path() - load the initrd from the Linux initrd device path
555 * @load_addr: pointer to store the address where the initrd was loaded
556 * @load_size: pointer to store the size of the loaded initrd
557 * @max: upper limit for the initrd memory allocation
558 *
559 * Return:
560 * * %EFI_SUCCESS if the initrd was loaded successfully, in which
561 * case @load_addr and @load_size are assigned accordingly
562 * * %EFI_NOT_FOUND if no LoadFile2 protocol exists on the initrd device path
563 * * %EFI_INVALID_PARAMETER if load_addr == NULL or load_size == NULL
564 * * %EFI_OUT_OF_RESOURCES if memory allocation failed
565 * * %EFI_LOAD_ERROR in all other cases
566 */
567 static
efi_load_initrd_dev_path(unsigned long * load_addr,unsigned long * load_size,unsigned long max)568 efi_status_t efi_load_initrd_dev_path(unsigned long *load_addr,
569 unsigned long *load_size,
570 unsigned long max)
571 {
572 efi_guid_t lf2_proto_guid = EFI_LOAD_FILE2_PROTOCOL_GUID;
573 efi_device_path_protocol_t *dp;
574 efi_load_file2_protocol_t *lf2;
575 unsigned long initrd_addr;
576 unsigned long initrd_size;
577 efi_handle_t handle;
578 efi_status_t status;
579
580 dp = (efi_device_path_protocol_t *)&initrd_dev_path;
581 status = efi_bs_call(locate_device_path, &lf2_proto_guid, &dp, &handle);
582 if (status != EFI_SUCCESS)
583 return status;
584
585 status = efi_bs_call(handle_protocol, handle, &lf2_proto_guid,
586 (void **)&lf2);
587 if (status != EFI_SUCCESS)
588 return status;
589
590 status = efi_call_proto(lf2, load_file, dp, false, &initrd_size, NULL);
591 if (status != EFI_BUFFER_TOO_SMALL)
592 return EFI_LOAD_ERROR;
593
594 status = efi_allocate_pages(initrd_size, &initrd_addr, max);
595 if (status != EFI_SUCCESS)
596 return status;
597
598 status = efi_call_proto(lf2, load_file, dp, false, &initrd_size,
599 (void *)initrd_addr);
600 if (status != EFI_SUCCESS) {
601 efi_free(initrd_size, initrd_addr);
602 return EFI_LOAD_ERROR;
603 }
604
605 *load_addr = initrd_addr;
606 *load_size = initrd_size;
607 return EFI_SUCCESS;
608 }
609
610 static
efi_load_initrd_cmdline(efi_loaded_image_t * image,unsigned long * load_addr,unsigned long * load_size,unsigned long soft_limit,unsigned long hard_limit)611 efi_status_t efi_load_initrd_cmdline(efi_loaded_image_t *image,
612 unsigned long *load_addr,
613 unsigned long *load_size,
614 unsigned long soft_limit,
615 unsigned long hard_limit)
616 {
617 if (!IS_ENABLED(CONFIG_EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER) ||
618 (IS_ENABLED(CONFIG_X86) && (!efi_is_native() || image == NULL))) {
619 *load_addr = *load_size = 0;
620 return EFI_SUCCESS;
621 }
622
623 return handle_cmdline_files(image, L"initrd=", sizeof(L"initrd=") - 2,
624 soft_limit, hard_limit,
625 load_addr, load_size);
626 }
627
628 static const struct {
629 efi_tcg2_event_t event_data;
630 efi_tcg2_tagged_event_t tagged_event;
631 u8 tagged_event_data[];
632 } initrd_tcg2_event = {
633 {
634 sizeof(initrd_tcg2_event) + sizeof("Linux initrd"),
635 {
636 sizeof(initrd_tcg2_event.event_data.event_header),
637 EFI_TCG2_EVENT_HEADER_VERSION,
638 9,
639 EV_EVENT_TAG,
640 },
641 },
642 {
643 INITRD_EVENT_TAG_ID,
644 sizeof("Linux initrd"),
645 },
646 { "Linux initrd" },
647 };
648
efi_measure_initrd(unsigned long load_addr,unsigned long load_size)649 static void efi_measure_initrd(unsigned long load_addr, unsigned long load_size)
650 {
651 efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID;
652 efi_tcg2_protocol_t *tcg2 = NULL;
653 efi_status_t status;
654
655 efi_bs_call(locate_protocol, &tcg2_guid, NULL, (void **)&tcg2);
656 if (tcg2) {
657 status = efi_call_proto(tcg2, hash_log_extend_event,
658 0, load_addr, load_size,
659 &initrd_tcg2_event.event_data);
660 if (status != EFI_SUCCESS)
661 efi_warn("Failed to measure initrd data: 0x%lx\n",
662 status);
663 else
664 efi_info("Measured initrd data into PCR %d\n",
665 initrd_tcg2_event.event_data.event_header.pcr_index);
666 }
667 }
668
669 /**
670 * efi_load_initrd() - Load initial RAM disk
671 * @image: EFI loaded image protocol
672 * @load_addr: pointer to loaded initrd
673 * @load_size: size of loaded initrd
674 * @soft_limit: preferred address for loading the initrd
675 * @hard_limit: upper limit address for loading the initrd
676 *
677 * Return: status code
678 */
efi_load_initrd(efi_loaded_image_t * image,unsigned long * load_addr,unsigned long * load_size,unsigned long soft_limit,unsigned long hard_limit)679 efi_status_t efi_load_initrd(efi_loaded_image_t *image,
680 unsigned long *load_addr,
681 unsigned long *load_size,
682 unsigned long soft_limit,
683 unsigned long hard_limit)
684 {
685 efi_status_t status;
686
687 if (efi_noinitrd) {
688 *load_addr = *load_size = 0;
689 status = EFI_SUCCESS;
690 } else {
691 status = efi_load_initrd_dev_path(load_addr, load_size, hard_limit);
692 if (status == EFI_SUCCESS) {
693 efi_info("Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path\n");
694 if (*load_size > 0)
695 efi_measure_initrd(*load_addr, *load_size);
696 } else if (status == EFI_NOT_FOUND) {
697 status = efi_load_initrd_cmdline(image, load_addr, load_size,
698 soft_limit, hard_limit);
699 if (status == EFI_SUCCESS && *load_size > 0)
700 efi_info("Loaded initrd from command line option\n");
701 }
702 if (status != EFI_SUCCESS) {
703 efi_err("Failed to load initrd: 0x%lx\n", status);
704 *load_addr = *load_size = 0;
705 }
706 }
707
708 return status;
709 }
710
711 /**
712 * efi_wait_for_key() - Wait for key stroke
713 * @usec: number of microseconds to wait for key stroke
714 * @key: key entered
715 *
716 * Wait for up to @usec microseconds for a key stroke.
717 *
718 * Return: status code, EFI_SUCCESS if key received
719 */
efi_wait_for_key(unsigned long usec,efi_input_key_t * key)720 efi_status_t efi_wait_for_key(unsigned long usec, efi_input_key_t *key)
721 {
722 efi_event_t events[2], timer;
723 unsigned long index;
724 efi_simple_text_input_protocol_t *con_in;
725 efi_status_t status;
726
727 con_in = efi_table_attr(efi_system_table, con_in);
728 if (!con_in)
729 return EFI_UNSUPPORTED;
730 efi_set_event_at(events, 0, efi_table_attr(con_in, wait_for_key));
731
732 status = efi_bs_call(create_event, EFI_EVT_TIMER, 0, NULL, NULL, &timer);
733 if (status != EFI_SUCCESS)
734 return status;
735
736 status = efi_bs_call(set_timer, timer, EfiTimerRelative,
737 EFI_100NSEC_PER_USEC * usec);
738 if (status != EFI_SUCCESS)
739 return status;
740 efi_set_event_at(events, 1, timer);
741
742 status = efi_bs_call(wait_for_event, 2, events, &index);
743 if (status == EFI_SUCCESS) {
744 if (index == 0)
745 status = efi_call_proto(con_in, read_keystroke, key);
746 else
747 status = EFI_TIMEOUT;
748 }
749
750 efi_bs_call(close_event, timer);
751
752 return status;
753 }
754