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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2#include <linux/types.h>
   3#include <linux/string.h>
   4#include <linux/init.h>
   5#include <linux/module.h>
   6#include <linux/ctype.h>
   7#include <linux/dmi.h>
   8#include <linux/efi.h>
   9#include <linux/memblock.h>
  10#include <linux/random.h>
  11#include <asm/dmi.h>
  12#include <asm/unaligned.h>
  13
  14#ifndef SMBIOS_ENTRY_POINT_SCAN_START
  15#define SMBIOS_ENTRY_POINT_SCAN_START 0xF0000
  16#endif
  17
  18struct kobject *dmi_kobj;
  19EXPORT_SYMBOL_GPL(dmi_kobj);
  20
  21/*
  22 * DMI stands for "Desktop Management Interface".  It is part
  23 * of and an antecedent to, SMBIOS, which stands for System
  24 * Management BIOS.  See further: https://www.dmtf.org/standards
  25 */
  26static const char dmi_empty_string[] = "";
  27
  28static u32 dmi_ver __initdata;
  29static u32 dmi_len;
  30static u16 dmi_num;
  31static u8 smbios_entry_point[32];
  32static int smbios_entry_point_size;
  33
  34/* DMI system identification string used during boot */
  35static char dmi_ids_string[128] __initdata;
  36
  37static struct dmi_memdev_info {
  38	const char *device;
  39	const char *bank;
  40	u64 size;		/* bytes */
  41	u16 handle;
  42	u8 type;		/* DDR2, DDR3, DDR4 etc */
  43} *dmi_memdev;
  44static int dmi_memdev_nr;
  45
  46static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
  47{
  48	const u8 *bp = ((u8 *) dm) + dm->length;
  49	const u8 *nsp;
  50
  51	if (s) {
  52		while (--s > 0 && *bp)
  53			bp += strlen(bp) + 1;
  54
  55		/* Strings containing only spaces are considered empty */
  56		nsp = bp;
  57		while (*nsp == ' ')
  58			nsp++;
  59		if (*nsp != '\0')
  60			return bp;
  61	}
  62
  63	return dmi_empty_string;
  64}
  65
  66static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  67{
  68	const char *bp = dmi_string_nosave(dm, s);
  69	char *str;
  70	size_t len;
  71
  72	if (bp == dmi_empty_string)
  73		return dmi_empty_string;
  74
  75	len = strlen(bp) + 1;
  76	str = dmi_alloc(len);
  77	if (str != NULL)
  78		strcpy(str, bp);
  79
  80	return str;
  81}
  82
  83/*
  84 *	We have to be cautious here. We have seen BIOSes with DMI pointers
  85 *	pointing to completely the wrong place for example
  86 */
  87static void dmi_decode_table(u8 *buf,
  88			     void (*decode)(const struct dmi_header *, void *),
  89			     void *private_data)
  90{
  91	u8 *data = buf;
  92	int i = 0;
  93
  94	/*
  95	 * Stop when we have seen all the items the table claimed to have
  96	 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
  97	 * >= 3.0 only) OR we run off the end of the table (should never
  98	 * happen but sometimes does on bogus implementations.)
  99	 */
 100	while ((!dmi_num || i < dmi_num) &&
 101	       (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
 102		const struct dmi_header *dm = (const struct dmi_header *)data;
 103
 104		/*
 105		 *  We want to know the total length (formatted area and
 106		 *  strings) before decoding to make sure we won't run off the
 107		 *  table in dmi_decode or dmi_string
 108		 */
 109		data += dm->length;
 110		while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
 111			data++;
 112		if (data - buf < dmi_len - 1)
 113			decode(dm, private_data);
 114
 115		data += 2;
 116		i++;
 117
 118		/*
 119		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
 120		 * For tables behind a 64-bit entry point, we have no item
 121		 * count and no exact table length, so stop on end-of-table
 122		 * marker. For tables behind a 32-bit entry point, we have
 123		 * seen OEM structures behind the end-of-table marker on
 124		 * some systems, so don't trust it.
 125		 */
 126		if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
 127			break;
 128	}
 129
 130	/* Trim DMI table length if needed */
 131	if (dmi_len > data - buf)
 132		dmi_len = data - buf;
 133}
 134
 135static phys_addr_t dmi_base;
 136
 137static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
 138		void *))
 139{
 140	u8 *buf;
 141	u32 orig_dmi_len = dmi_len;
 142
 143	buf = dmi_early_remap(dmi_base, orig_dmi_len);
 144	if (buf == NULL)
 145		return -ENOMEM;
 146
 147	dmi_decode_table(buf, decode, NULL);
 148
 149	add_device_randomness(buf, dmi_len);
 150
 151	dmi_early_unmap(buf, orig_dmi_len);
 152	return 0;
 153}
 154
 155static int __init dmi_checksum(const u8 *buf, u8 len)
 156{
 157	u8 sum = 0;
 158	int a;
 159
 160	for (a = 0; a < len; a++)
 161		sum += buf[a];
 162
 163	return sum == 0;
 164}
 165
 166static const char *dmi_ident[DMI_STRING_MAX];
 167static LIST_HEAD(dmi_devices);
 168int dmi_available;
 169EXPORT_SYMBOL_GPL(dmi_available);
 170
 171/*
 172 *	Save a DMI string
 173 */
 174static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
 175		int string)
 176{
 177	const char *d = (const char *) dm;
 178	const char *p;
 179
 180	if (dmi_ident[slot] || dm->length <= string)
 181		return;
 182
 183	p = dmi_string(dm, d[string]);
 184	if (p == NULL)
 185		return;
 186
 187	dmi_ident[slot] = p;
 188}
 189
 190static void __init dmi_save_release(const struct dmi_header *dm, int slot,
 191		int index)
 192{
 193	const u8 *minor, *major;
 194	char *s;
 195
 196	/* If the table doesn't have the field, let's return */
 197	if (dmi_ident[slot] || dm->length < index)
 198		return;
 199
 200	minor = (u8 *) dm + index;
 201	major = (u8 *) dm + index - 1;
 202
 203	/* As per the spec, if the system doesn't support this field,
 204	 * the value is FF
 205	 */
 206	if (*major == 0xFF && *minor == 0xFF)
 207		return;
 208
 209	s = dmi_alloc(8);
 210	if (!s)
 211		return;
 212
 213	sprintf(s, "%u.%u", *major, *minor);
 214
 215	dmi_ident[slot] = s;
 216}
 217
 218static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
 219		int index)
 220{
 221	const u8 *d;
 222	char *s;
 223	int is_ff = 1, is_00 = 1, i;
 224
 225	if (dmi_ident[slot] || dm->length < index + 16)
 226		return;
 227
 228	d = (u8 *) dm + index;
 229	for (i = 0; i < 16 && (is_ff || is_00); i++) {
 230		if (d[i] != 0x00)
 231			is_00 = 0;
 232		if (d[i] != 0xFF)
 233			is_ff = 0;
 234	}
 235
 236	if (is_ff || is_00)
 237		return;
 238
 239	s = dmi_alloc(16*2+4+1);
 240	if (!s)
 241		return;
 242
 243	/*
 244	 * As of version 2.6 of the SMBIOS specification, the first 3 fields of
 245	 * the UUID are supposed to be little-endian encoded.  The specification
 246	 * says that this is the defacto standard.
 247	 */
 248	if (dmi_ver >= 0x020600)
 249		sprintf(s, "%pUl", d);
 250	else
 251		sprintf(s, "%pUb", d);
 252
 253	dmi_ident[slot] = s;
 254}
 255
 256static void __init dmi_save_type(const struct dmi_header *dm, int slot,
 257		int index)
 258{
 259	const u8 *d;
 260	char *s;
 261
 262	if (dmi_ident[slot] || dm->length <= index)
 263		return;
 264
 265	s = dmi_alloc(4);
 266	if (!s)
 267		return;
 268
 269	d = (u8 *) dm + index;
 270	sprintf(s, "%u", *d & 0x7F);
 271	dmi_ident[slot] = s;
 272}
 273
 274static void __init dmi_save_one_device(int type, const char *name)
 275{
 276	struct dmi_device *dev;
 277
 278	/* No duplicate device */
 279	if (dmi_find_device(type, name, NULL))
 280		return;
 281
 282	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 283	if (!dev)
 284		return;
 285
 286	dev->type = type;
 287	strcpy((char *)(dev + 1), name);
 288	dev->name = (char *)(dev + 1);
 289	dev->device_data = NULL;
 290	list_add(&dev->list, &dmi_devices);
 291}
 292
 293static void __init dmi_save_devices(const struct dmi_header *dm)
 294{
 295	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
 296
 297	for (i = 0; i < count; i++) {
 298		const char *d = (char *)(dm + 1) + (i * 2);
 299
 300		/* Skip disabled device */
 301		if ((*d & 0x80) == 0)
 302			continue;
 303
 304		dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
 305	}
 306}
 307
 308static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
 309{
 310	int i, count;
 311	struct dmi_device *dev;
 312
 313	if (dm->length < 0x05)
 314		return;
 315
 316	count = *(u8 *)(dm + 1);
 317	for (i = 1; i <= count; i++) {
 318		const char *devname = dmi_string(dm, i);
 319
 320		if (devname == dmi_empty_string)
 321			continue;
 322
 323		dev = dmi_alloc(sizeof(*dev));
 324		if (!dev)
 325			break;
 326
 327		dev->type = DMI_DEV_TYPE_OEM_STRING;
 328		dev->name = devname;
 329		dev->device_data = NULL;
 330
 331		list_add(&dev->list, &dmi_devices);
 332	}
 333}
 334
 335static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
 336{
 337	struct dmi_device *dev;
 338	void *data;
 339
 340	data = dmi_alloc(dm->length);
 341	if (data == NULL)
 342		return;
 343
 344	memcpy(data, dm, dm->length);
 345
 346	dev = dmi_alloc(sizeof(*dev));
 347	if (!dev)
 348		return;
 349
 350	dev->type = DMI_DEV_TYPE_IPMI;
 351	dev->name = "IPMI controller";
 352	dev->device_data = data;
 353
 354	list_add_tail(&dev->list, &dmi_devices);
 355}
 356
 357static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
 358					int devfn, const char *name, int type)
 359{
 360	struct dmi_dev_onboard *dev;
 361
 362	/* Ignore invalid values */
 363	if (type == DMI_DEV_TYPE_DEV_SLOT &&
 364	    segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
 365		return;
 366
 367	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 368	if (!dev)
 369		return;
 370
 371	dev->instance = instance;
 372	dev->segment = segment;
 373	dev->bus = bus;
 374	dev->devfn = devfn;
 375
 376	strcpy((char *)&dev[1], name);
 377	dev->dev.type = type;
 378	dev->dev.name = (char *)&dev[1];
 379	dev->dev.device_data = dev;
 380
 381	list_add(&dev->dev.list, &dmi_devices);
 382}
 383
 384static void __init dmi_save_extended_devices(const struct dmi_header *dm)
 385{
 386	const char *name;
 387	const u8 *d = (u8 *)dm;
 388
 389	if (dm->length < 0x0B)
 390		return;
 391
 392	/* Skip disabled device */
 393	if ((d[0x5] & 0x80) == 0)
 394		return;
 395
 396	name = dmi_string_nosave(dm, d[0x4]);
 397	dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
 398			     DMI_DEV_TYPE_DEV_ONBOARD);
 399	dmi_save_one_device(d[0x5] & 0x7f, name);
 400}
 401
 402static void __init dmi_save_system_slot(const struct dmi_header *dm)
 403{
 404	const u8 *d = (u8 *)dm;
 405
 406	/* Need SMBIOS 2.6+ structure */
 407	if (dm->length < 0x11)
 408		return;
 409	dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
 410			     d[0x10], dmi_string_nosave(dm, d[0x4]),
 411			     DMI_DEV_TYPE_DEV_SLOT);
 412}
 413
 414static void __init count_mem_devices(const struct dmi_header *dm, void *v)
 415{
 416	if (dm->type != DMI_ENTRY_MEM_DEVICE)
 417		return;
 418	dmi_memdev_nr++;
 419}
 420
 421static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 422{
 423	const char *d = (const char *)dm;
 424	static int nr;
 425	u64 bytes;
 426	u16 size;
 427
 428	if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x13)
 429		return;
 430	if (nr >= dmi_memdev_nr) {
 431		pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 432		return;
 433	}
 434	dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 435	dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 436	dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 437	dmi_memdev[nr].type = d[0x12];
 438
 439	size = get_unaligned((u16 *)&d[0xC]);
 440	if (size == 0)
 441		bytes = 0;
 442	else if (size == 0xffff)
 443		bytes = ~0ull;
 444	else if (size & 0x8000)
 445		bytes = (u64)(size & 0x7fff) << 10;
 446	else if (size != 0x7fff || dm->length < 0x20)
 447		bytes = (u64)size << 20;
 448	else
 449		bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
 450
 451	dmi_memdev[nr].size = bytes;
 452	nr++;
 453}
 454
 455static void __init dmi_memdev_walk(void)
 456{
 457	if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
 458		dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
 459		if (dmi_memdev)
 460			dmi_walk_early(save_mem_devices);
 461	}
 462}
 463
 464/*
 465 *	Process a DMI table entry. Right now all we care about are the BIOS
 466 *	and machine entries. For 2.5 we should pull the smbus controller info
 467 *	out of here.
 468 */
 469static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
 470{
 471	switch (dm->type) {
 472	case 0:		/* BIOS Information */
 473		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
 474		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
 475		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
 476		dmi_save_release(dm, DMI_BIOS_RELEASE, 21);
 477		dmi_save_release(dm, DMI_EC_FIRMWARE_RELEASE, 23);
 478		break;
 479	case 1:		/* System Information */
 480		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
 481		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
 482		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 483		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 484		dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
 485		dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
 486		dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
 487		break;
 488	case 2:		/* Base Board Information */
 489		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
 490		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
 491		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
 492		dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
 493		dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
 494		break;
 495	case 3:		/* Chassis Information */
 496		dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
 497		dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
 498		dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
 499		dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
 500		dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
 501		break;
 502	case 9:		/* System Slots */
 503		dmi_save_system_slot(dm);
 504		break;
 505	case 10:	/* Onboard Devices Information */
 506		dmi_save_devices(dm);
 507		break;
 508	case 11:	/* OEM Strings */
 509		dmi_save_oem_strings_devices(dm);
 510		break;
 511	case 38:	/* IPMI Device Information */
 512		dmi_save_ipmi_device(dm);
 513		break;
 514	case 41:	/* Onboard Devices Extended Information */
 515		dmi_save_extended_devices(dm);
 516	}
 517}
 518
 519static int __init print_filtered(char *buf, size_t len, const char *info)
 520{
 521	int c = 0;
 522	const char *p;
 523
 524	if (!info)
 525		return c;
 526
 527	for (p = info; *p; p++)
 528		if (isprint(*p))
 529			c += scnprintf(buf + c, len - c, "%c", *p);
 530		else
 531			c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
 532	return c;
 533}
 534
 535static void __init dmi_format_ids(char *buf, size_t len)
 536{
 537	int c = 0;
 538	const char *board;	/* Board Name is optional */
 539
 540	c += print_filtered(buf + c, len - c,
 541			    dmi_get_system_info(DMI_SYS_VENDOR));
 542	c += scnprintf(buf + c, len - c, " ");
 543	c += print_filtered(buf + c, len - c,
 544			    dmi_get_system_info(DMI_PRODUCT_NAME));
 545
 546	board = dmi_get_system_info(DMI_BOARD_NAME);
 547	if (board) {
 548		c += scnprintf(buf + c, len - c, "/");
 549		c += print_filtered(buf + c, len - c, board);
 550	}
 551	c += scnprintf(buf + c, len - c, ", BIOS ");
 552	c += print_filtered(buf + c, len - c,
 553			    dmi_get_system_info(DMI_BIOS_VERSION));
 554	c += scnprintf(buf + c, len - c, " ");
 555	c += print_filtered(buf + c, len - c,
 556			    dmi_get_system_info(DMI_BIOS_DATE));
 557}
 558
 559/*
 560 * Check for DMI/SMBIOS headers in the system firmware image.  Any
 561 * SMBIOS header must start 16 bytes before the DMI header, so take a
 562 * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
 563 * 0.  If the DMI header is present, set dmi_ver accordingly (SMBIOS
 564 * takes precedence) and return 0.  Otherwise return 1.
 565 */
 566static int __init dmi_present(const u8 *buf)
 567{
 568	u32 smbios_ver;
 569
 570	/*
 571	 * The size of this structure is 31 bytes, but we also accept value
 572	 * 30 due to a mistake in SMBIOS specification version 2.1.
 573	 */
 574	if (memcmp(buf, "_SM_", 4) == 0 &&
 575	    buf[5] >= 30 && buf[5] <= 32 &&
 576	    dmi_checksum(buf, buf[5])) {
 577		smbios_ver = get_unaligned_be16(buf + 6);
 578		smbios_entry_point_size = buf[5];
 579		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 580
 581		/* Some BIOS report weird SMBIOS version, fix that up */
 582		switch (smbios_ver) {
 583		case 0x021F:
 584		case 0x0221:
 585			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
 586				 smbios_ver & 0xFF, 3);
 587			smbios_ver = 0x0203;
 588			break;
 589		case 0x0233:
 590			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
 591			smbios_ver = 0x0206;
 592			break;
 593		}
 594	} else {
 595		smbios_ver = 0;
 596	}
 597
 598	buf += 16;
 599
 600	if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
 601		if (smbios_ver)
 602			dmi_ver = smbios_ver;
 603		else
 604			dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
 605		dmi_ver <<= 8;
 606		dmi_num = get_unaligned_le16(buf + 12);
 607		dmi_len = get_unaligned_le16(buf + 6);
 608		dmi_base = get_unaligned_le32(buf + 8);
 609
 610		if (dmi_walk_early(dmi_decode) == 0) {
 611			if (smbios_ver) {
 612				pr_info("SMBIOS %d.%d present.\n",
 613					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 614			} else {
 615				smbios_entry_point_size = 15;
 616				memcpy(smbios_entry_point, buf,
 617				       smbios_entry_point_size);
 618				pr_info("Legacy DMI %d.%d present.\n",
 619					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 620			}
 621			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 622			pr_info("DMI: %s\n", dmi_ids_string);
 623			return 0;
 624		}
 625	}
 626
 627	return 1;
 628}
 629
 630/*
 631 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
 632 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
 633 */
 634static int __init dmi_smbios3_present(const u8 *buf)
 635{
 636	if (memcmp(buf, "_SM3_", 5) == 0 &&
 637	    buf[6] >= 24 && buf[6] <= 32 &&
 638	    dmi_checksum(buf, buf[6])) {
 639		dmi_ver = get_unaligned_be24(buf + 7);
 640		dmi_num = 0;			/* No longer specified */
 641		dmi_len = get_unaligned_le32(buf + 12);
 642		dmi_base = get_unaligned_le64(buf + 16);
 643		smbios_entry_point_size = buf[6];
 644		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 645
 646		if (dmi_walk_early(dmi_decode) == 0) {
 647			pr_info("SMBIOS %d.%d.%d present.\n",
 648				dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
 649				dmi_ver & 0xFF);
 650			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 651			pr_info("DMI: %s\n", dmi_ids_string);
 652			return 0;
 653		}
 654	}
 655	return 1;
 656}
 657
 658static void __init dmi_scan_machine(void)
 659{
 660	char __iomem *p, *q;
 661	char buf[32];
 662
 663	if (efi_enabled(EFI_CONFIG_TABLES)) {
 664		/*
 665		 * According to the DMTF SMBIOS reference spec v3.0.0, it is
 666		 * allowed to define both the 64-bit entry point (smbios3) and
 667		 * the 32-bit entry point (smbios), in which case they should
 668		 * either both point to the same SMBIOS structure table, or the
 669		 * table pointed to by the 64-bit entry point should contain a
 670		 * superset of the table contents pointed to by the 32-bit entry
 671		 * point (section 5.2)
 672		 * This implies that the 64-bit entry point should have
 673		 * precedence if it is defined and supported by the OS. If we
 674		 * have the 64-bit entry point, but fail to decode it, fall
 675		 * back to the legacy one (if available)
 676		 */
 677		if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
 678			p = dmi_early_remap(efi.smbios3, 32);
 679			if (p == NULL)
 680				goto error;
 681			memcpy_fromio(buf, p, 32);
 682			dmi_early_unmap(p, 32);
 683
 684			if (!dmi_smbios3_present(buf)) {
 685				dmi_available = 1;
 686				return;
 687			}
 688		}
 689		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 690			goto error;
 691
 692		/* This is called as a core_initcall() because it isn't
 693		 * needed during early boot.  This also means we can
 694		 * iounmap the space when we're done with it.
 695		 */
 696		p = dmi_early_remap(efi.smbios, 32);
 697		if (p == NULL)
 698			goto error;
 699		memcpy_fromio(buf, p, 32);
 700		dmi_early_unmap(p, 32);
 701
 702		if (!dmi_present(buf)) {
 703			dmi_available = 1;
 704			return;
 705		}
 706	} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
 707		p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
 708		if (p == NULL)
 709			goto error;
 710
 711		/*
 712		 * Same logic as above, look for a 64-bit entry point
 713		 * first, and if not found, fall back to 32-bit entry point.
 714		 */
 715		memcpy_fromio(buf, p, 16);
 716		for (q = p + 16; q < p + 0x10000; q += 16) {
 717			memcpy_fromio(buf + 16, q, 16);
 718			if (!dmi_smbios3_present(buf)) {
 719				dmi_available = 1;
 720				dmi_early_unmap(p, 0x10000);
 721				return;
 722			}
 723			memcpy(buf, buf + 16, 16);
 724		}
 725
 726		/*
 727		 * Iterate over all possible DMI header addresses q.
 728		 * Maintain the 32 bytes around q in buf.  On the
 729		 * first iteration, substitute zero for the
 730		 * out-of-range bytes so there is no chance of falsely
 731		 * detecting an SMBIOS header.
 732		 */
 733		memset(buf, 0, 16);
 734		for (q = p; q < p + 0x10000; q += 16) {
 735			memcpy_fromio(buf + 16, q, 16);
 736			if (!dmi_present(buf)) {
 737				dmi_available = 1;
 738				dmi_early_unmap(p, 0x10000);
 739				return;
 740			}
 741			memcpy(buf, buf + 16, 16);
 742		}
 743		dmi_early_unmap(p, 0x10000);
 744	}
 745 error:
 746	pr_info("DMI not present or invalid.\n");
 747}
 748
 749static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
 750			      struct bin_attribute *attr, char *buf,
 751			      loff_t pos, size_t count)
 752{
 753	memcpy(buf, attr->private + pos, count);
 754	return count;
 755}
 756
 757static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
 758static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
 759
 760static int __init dmi_init(void)
 761{
 762	struct kobject *tables_kobj;
 763	u8 *dmi_table;
 764	int ret = -ENOMEM;
 765
 766	if (!dmi_available)
 767		return 0;
 768
 769	/*
 770	 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
 771	 * even after farther error, as it can be used by other modules like
 772	 * dmi-sysfs.
 773	 */
 774	dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
 775	if (!dmi_kobj)
 776		goto err;
 777
 778	tables_kobj = kobject_create_and_add("tables", dmi_kobj);
 779	if (!tables_kobj)
 780		goto err;
 781
 782	dmi_table = dmi_remap(dmi_base, dmi_len);
 783	if (!dmi_table)
 784		goto err_tables;
 785
 786	bin_attr_smbios_entry_point.size = smbios_entry_point_size;
 787	bin_attr_smbios_entry_point.private = smbios_entry_point;
 788	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
 789	if (ret)
 790		goto err_unmap;
 791
 792	bin_attr_DMI.size = dmi_len;
 793	bin_attr_DMI.private = dmi_table;
 794	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
 795	if (!ret)
 796		return 0;
 797
 798	sysfs_remove_bin_file(tables_kobj,
 799			      &bin_attr_smbios_entry_point);
 800 err_unmap:
 801	dmi_unmap(dmi_table);
 802 err_tables:
 803	kobject_del(tables_kobj);
 804	kobject_put(tables_kobj);
 805 err:
 806	pr_err("dmi: Firmware registration failed.\n");
 807
 808	return ret;
 809}
 810subsys_initcall(dmi_init);
 811
 812/**
 813 *	dmi_setup - scan and setup DMI system information
 814 *
 815 *	Scan the DMI system information. This setups DMI identifiers
 816 *	(dmi_system_id) for printing it out on task dumps and prepares
 817 *	DIMM entry information (dmi_memdev_info) from the SMBIOS table
 818 *	for using this when reporting memory errors.
 819 */
 820void __init dmi_setup(void)
 821{
 822	dmi_scan_machine();
 823	if (!dmi_available)
 824		return;
 825
 826	dmi_memdev_walk();
 827	dump_stack_set_arch_desc("%s", dmi_ids_string);
 828}
 829
 830/**
 831 *	dmi_matches - check if dmi_system_id structure matches system DMI data
 832 *	@dmi: pointer to the dmi_system_id structure to check
 833 */
 834static bool dmi_matches(const struct dmi_system_id *dmi)
 835{
 836	int i;
 837
 838	for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
 839		int s = dmi->matches[i].slot;
 840		if (s == DMI_NONE)
 841			break;
 842		if (s == DMI_OEM_STRING) {
 843			/* DMI_OEM_STRING must be exact match */
 844			const struct dmi_device *valid;
 845
 846			valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
 847						dmi->matches[i].substr, NULL);
 848			if (valid)
 849				continue;
 850		} else if (dmi_ident[s]) {
 851			if (dmi->matches[i].exact_match) {
 852				if (!strcmp(dmi_ident[s],
 853					    dmi->matches[i].substr))
 854					continue;
 855			} else {
 856				if (strstr(dmi_ident[s],
 857					   dmi->matches[i].substr))
 858					continue;
 859			}
 860		}
 861
 862		/* No match */
 863		return false;
 864	}
 865	return true;
 866}
 867
 868/**
 869 *	dmi_is_end_of_table - check for end-of-table marker
 870 *	@dmi: pointer to the dmi_system_id structure to check
 871 */
 872static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
 873{
 874	return dmi->matches[0].slot == DMI_NONE;
 875}
 876
 877/**
 878 *	dmi_check_system - check system DMI data
 879 *	@list: array of dmi_system_id structures to match against
 880 *		All non-null elements of the list must match
 881 *		their slot's (field index's) data (i.e., each
 882 *		list string must be a substring of the specified
 883 *		DMI slot's string data) to be considered a
 884 *		successful match.
 885 *
 886 *	Walk the blacklist table running matching functions until someone
 887 *	returns non zero or we hit the end. Callback function is called for
 888 *	each successful match. Returns the number of matches.
 889 *
 890 *	dmi_setup must be called before this function is called.
 891 */
 892int dmi_check_system(const struct dmi_system_id *list)
 893{
 894	int count = 0;
 895	const struct dmi_system_id *d;
 896
 897	for (d = list; !dmi_is_end_of_table(d); d++)
 898		if (dmi_matches(d)) {
 899			count++;
 900			if (d->callback && d->callback(d))
 901				break;
 902		}
 903
 904	return count;
 905}
 906EXPORT_SYMBOL(dmi_check_system);
 907
 908/**
 909 *	dmi_first_match - find dmi_system_id structure matching system DMI data
 910 *	@list: array of dmi_system_id structures to match against
 911 *		All non-null elements of the list must match
 912 *		their slot's (field index's) data (i.e., each
 913 *		list string must be a substring of the specified
 914 *		DMI slot's string data) to be considered a
 915 *		successful match.
 916 *
 917 *	Walk the blacklist table until the first match is found.  Return the
 918 *	pointer to the matching entry or NULL if there's no match.
 919 *
 920 *	dmi_setup must be called before this function is called.
 921 */
 922const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 923{
 924	const struct dmi_system_id *d;
 925
 926	for (d = list; !dmi_is_end_of_table(d); d++)
 927		if (dmi_matches(d))
 928			return d;
 929
 930	return NULL;
 931}
 932EXPORT_SYMBOL(dmi_first_match);
 933
 934/**
 935 *	dmi_get_system_info - return DMI data value
 936 *	@field: data index (see enum dmi_field)
 937 *
 938 *	Returns one DMI data value, can be used to perform
 939 *	complex DMI data checks.
 940 */
 941const char *dmi_get_system_info(int field)
 942{
 943	return dmi_ident[field];
 944}
 945EXPORT_SYMBOL(dmi_get_system_info);
 946
 947/**
 948 * dmi_name_in_serial - Check if string is in the DMI product serial information
 949 * @str: string to check for
 950 */
 951int dmi_name_in_serial(const char *str)
 952{
 953	int f = DMI_PRODUCT_SERIAL;
 954	if (dmi_ident[f] && strstr(dmi_ident[f], str))
 955		return 1;
 956	return 0;
 957}
 958
 959/**
 960 *	dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
 961 *	@str: Case sensitive Name
 962 */
 963int dmi_name_in_vendors(const char *str)
 964{
 965	static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 966	int i;
 967	for (i = 0; fields[i] != DMI_NONE; i++) {
 968		int f = fields[i];
 969		if (dmi_ident[f] && strstr(dmi_ident[f], str))
 970			return 1;
 971	}
 972	return 0;
 973}
 974EXPORT_SYMBOL(dmi_name_in_vendors);
 975
 976/**
 977 *	dmi_find_device - find onboard device by type/name
 978 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 979 *	@name: device name string or %NULL to match all
 980 *	@from: previous device found in search, or %NULL for new search.
 981 *
 982 *	Iterates through the list of known onboard devices. If a device is
 983 *	found with a matching @type and @name, a pointer to its device
 984 *	structure is returned.  Otherwise, %NULL is returned.
 985 *	A new search is initiated by passing %NULL as the @from argument.
 986 *	If @from is not %NULL, searches continue from next device.
 987 */
 988const struct dmi_device *dmi_find_device(int type, const char *name,
 989				    const struct dmi_device *from)
 990{
 991	const struct list_head *head = from ? &from->list : &dmi_devices;
 992	struct list_head *d;
 993
 994	for (d = head->next; d != &dmi_devices; d = d->next) {
 995		const struct dmi_device *dev =
 996			list_entry(d, struct dmi_device, list);
 997
 998		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
 999		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
1000			return dev;
1001	}
1002
1003	return NULL;
1004}
1005EXPORT_SYMBOL(dmi_find_device);
1006
1007/**
1008 *	dmi_get_date - parse a DMI date
1009 *	@field:	data index (see enum dmi_field)
1010 *	@yearp: optional out parameter for the year
1011 *	@monthp: optional out parameter for the month
1012 *	@dayp: optional out parameter for the day
1013 *
1014 *	The date field is assumed to be in the form resembling
1015 *	[mm[/dd]]/yy[yy] and the result is stored in the out
1016 *	parameters any or all of which can be omitted.
1017 *
1018 *	If the field doesn't exist, all out parameters are set to zero
1019 *	and false is returned.  Otherwise, true is returned with any
1020 *	invalid part of date set to zero.
1021 *
1022 *	On return, year, month and day are guaranteed to be in the
1023 *	range of [0,9999], [0,12] and [0,31] respectively.
1024 */
1025bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1026{
1027	int year = 0, month = 0, day = 0;
1028	bool exists;
1029	const char *s, *y;
1030	char *e;
1031
1032	s = dmi_get_system_info(field);
1033	exists = s;
1034	if (!exists)
1035		goto out;
1036
1037	/*
1038	 * Determine year first.  We assume the date string resembles
1039	 * mm/dd/yy[yy] but the original code extracted only the year
1040	 * from the end.  Keep the behavior in the spirit of no
1041	 * surprises.
1042	 */
1043	y = strrchr(s, '/');
1044	if (!y)
1045		goto out;
1046
1047	y++;
1048	year = simple_strtoul(y, &e, 10);
1049	if (y != e && year < 100) {	/* 2-digit year */
1050		year += 1900;
1051		if (year < 1996)	/* no dates < spec 1.0 */
1052			year += 100;
1053	}
1054	if (year > 9999)		/* year should fit in %04d */
1055		year = 0;
1056
1057	/* parse the mm and dd */
1058	month = simple_strtoul(s, &e, 10);
1059	if (s == e || *e != '/' || !month || month > 12) {
1060		month = 0;
1061		goto out;
1062	}
1063
1064	s = e + 1;
1065	day = simple_strtoul(s, &e, 10);
1066	if (s == y || s == e || *e != '/' || day > 31)
1067		day = 0;
1068out:
1069	if (yearp)
1070		*yearp = year;
1071	if (monthp)
1072		*monthp = month;
1073	if (dayp)
1074		*dayp = day;
1075	return exists;
1076}
1077EXPORT_SYMBOL(dmi_get_date);
1078
1079/**
1080 *	dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1081 *
1082 *	Returns year on success, -ENXIO if DMI is not selected,
1083 *	or a different negative error code if DMI field is not present
1084 *	or not parseable.
1085 */
1086int dmi_get_bios_year(void)
1087{
1088	bool exists;
1089	int year;
1090
1091	exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1092	if (!exists)
1093		return -ENODATA;
1094
1095	return year ? year : -ERANGE;
1096}
1097EXPORT_SYMBOL(dmi_get_bios_year);
1098
1099/**
1100 *	dmi_walk - Walk the DMI table and get called back for every record
1101 *	@decode: Callback function
1102 *	@private_data: Private data to be passed to the callback function
1103 *
1104 *	Returns 0 on success, -ENXIO if DMI is not selected or not present,
1105 *	or a different negative error code if DMI walking fails.
1106 */
1107int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1108	     void *private_data)
1109{
1110	u8 *buf;
1111
1112	if (!dmi_available)
1113		return -ENXIO;
1114
1115	buf = dmi_remap(dmi_base, dmi_len);
1116	if (buf == NULL)
1117		return -ENOMEM;
1118
1119	dmi_decode_table(buf, decode, private_data);
1120
1121	dmi_unmap(buf);
1122	return 0;
1123}
1124EXPORT_SYMBOL_GPL(dmi_walk);
1125
1126/**
1127 * dmi_match - compare a string to the dmi field (if exists)
1128 * @f: DMI field identifier
1129 * @str: string to compare the DMI field to
1130 *
1131 * Returns true if the requested field equals to the str (including NULL).
1132 */
1133bool dmi_match(enum dmi_field f, const char *str)
1134{
1135	const char *info = dmi_get_system_info(f);
1136
1137	if (info == NULL || str == NULL)
1138		return info == str;
1139
1140	return !strcmp(info, str);
1141}
1142EXPORT_SYMBOL_GPL(dmi_match);
1143
1144void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1145{
1146	int n;
1147
1148	if (dmi_memdev == NULL)
1149		return;
1150
1151	for (n = 0; n < dmi_memdev_nr; n++) {
1152		if (handle == dmi_memdev[n].handle) {
1153			*bank = dmi_memdev[n].bank;
1154			*device = dmi_memdev[n].device;
1155			break;
1156		}
1157	}
1158}
1159EXPORT_SYMBOL_GPL(dmi_memdev_name);
1160
1161u64 dmi_memdev_size(u16 handle)
1162{
1163	int n;
1164
1165	if (dmi_memdev) {
1166		for (n = 0; n < dmi_memdev_nr; n++) {
1167			if (handle == dmi_memdev[n].handle)
1168				return dmi_memdev[n].size;
1169		}
1170	}
1171	return ~0ull;
1172}
1173EXPORT_SYMBOL_GPL(dmi_memdev_size);
1174
1175/**
1176 * dmi_memdev_type - get the memory type
1177 * @handle: DMI structure handle
1178 *
1179 * Return the DMI memory type of the module in the slot associated with the
1180 * given DMI handle, or 0x0 if no such DMI handle exists.
1181 */
1182u8 dmi_memdev_type(u16 handle)
1183{
1184	int n;
1185
1186	if (dmi_memdev) {
1187		for (n = 0; n < dmi_memdev_nr; n++) {
1188			if (handle == dmi_memdev[n].handle)
1189				return dmi_memdev[n].type;
1190		}
1191	}
1192	return 0x0;	/* Not a valid value */
1193}
1194EXPORT_SYMBOL_GPL(dmi_memdev_type);
1195
1196/**
1197 *	dmi_memdev_handle - get the DMI handle of a memory slot
1198 *	@slot: slot number
1199 *
1200 *	Return the DMI handle associated with a given memory slot, or %0xFFFF
1201 *      if there is no such slot.
1202 */
1203u16 dmi_memdev_handle(int slot)
1204{
1205	if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1206		return dmi_memdev[slot].handle;
1207
1208	return 0xffff;	/* Not a valid value */
1209}
1210EXPORT_SYMBOL_GPL(dmi_memdev_handle);
v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2#include <linux/types.h>
   3#include <linux/string.h>
   4#include <linux/init.h>
   5#include <linux/module.h>
   6#include <linux/ctype.h>
   7#include <linux/dmi.h>
   8#include <linux/efi.h>
   9#include <linux/memblock.h>
  10#include <linux/random.h>
  11#include <asm/dmi.h>
  12#include <asm/unaligned.h>
  13
 
 
 
 
  14struct kobject *dmi_kobj;
  15EXPORT_SYMBOL_GPL(dmi_kobj);
  16
  17/*
  18 * DMI stands for "Desktop Management Interface".  It is part
  19 * of and an antecedent to, SMBIOS, which stands for System
  20 * Management BIOS.  See further: http://www.dmtf.org/standards
  21 */
  22static const char dmi_empty_string[] = "";
  23
  24static u32 dmi_ver __initdata;
  25static u32 dmi_len;
  26static u16 dmi_num;
  27static u8 smbios_entry_point[32];
  28static int smbios_entry_point_size;
  29
  30/* DMI system identification string used during boot */
  31static char dmi_ids_string[128] __initdata;
  32
  33static struct dmi_memdev_info {
  34	const char *device;
  35	const char *bank;
  36	u64 size;		/* bytes */
  37	u16 handle;
 
  38} *dmi_memdev;
  39static int dmi_memdev_nr;
  40
  41static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
  42{
  43	const u8 *bp = ((u8 *) dm) + dm->length;
  44	const u8 *nsp;
  45
  46	if (s) {
  47		while (--s > 0 && *bp)
  48			bp += strlen(bp) + 1;
  49
  50		/* Strings containing only spaces are considered empty */
  51		nsp = bp;
  52		while (*nsp == ' ')
  53			nsp++;
  54		if (*nsp != '\0')
  55			return bp;
  56	}
  57
  58	return dmi_empty_string;
  59}
  60
  61static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  62{
  63	const char *bp = dmi_string_nosave(dm, s);
  64	char *str;
  65	size_t len;
  66
  67	if (bp == dmi_empty_string)
  68		return dmi_empty_string;
  69
  70	len = strlen(bp) + 1;
  71	str = dmi_alloc(len);
  72	if (str != NULL)
  73		strcpy(str, bp);
  74
  75	return str;
  76}
  77
  78/*
  79 *	We have to be cautious here. We have seen BIOSes with DMI pointers
  80 *	pointing to completely the wrong place for example
  81 */
  82static void dmi_decode_table(u8 *buf,
  83			     void (*decode)(const struct dmi_header *, void *),
  84			     void *private_data)
  85{
  86	u8 *data = buf;
  87	int i = 0;
  88
  89	/*
  90	 * Stop when we have seen all the items the table claimed to have
  91	 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
  92	 * >= 3.0 only) OR we run off the end of the table (should never
  93	 * happen but sometimes does on bogus implementations.)
  94	 */
  95	while ((!dmi_num || i < dmi_num) &&
  96	       (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
  97		const struct dmi_header *dm = (const struct dmi_header *)data;
  98
  99		/*
 100		 *  We want to know the total length (formatted area and
 101		 *  strings) before decoding to make sure we won't run off the
 102		 *  table in dmi_decode or dmi_string
 103		 */
 104		data += dm->length;
 105		while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
 106			data++;
 107		if (data - buf < dmi_len - 1)
 108			decode(dm, private_data);
 109
 110		data += 2;
 111		i++;
 112
 113		/*
 114		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
 115		 * For tables behind a 64-bit entry point, we have no item
 116		 * count and no exact table length, so stop on end-of-table
 117		 * marker. For tables behind a 32-bit entry point, we have
 118		 * seen OEM structures behind the end-of-table marker on
 119		 * some systems, so don't trust it.
 120		 */
 121		if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
 122			break;
 123	}
 124
 125	/* Trim DMI table length if needed */
 126	if (dmi_len > data - buf)
 127		dmi_len = data - buf;
 128}
 129
 130static phys_addr_t dmi_base;
 131
 132static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
 133		void *))
 134{
 135	u8 *buf;
 136	u32 orig_dmi_len = dmi_len;
 137
 138	buf = dmi_early_remap(dmi_base, orig_dmi_len);
 139	if (buf == NULL)
 140		return -ENOMEM;
 141
 142	dmi_decode_table(buf, decode, NULL);
 143
 144	add_device_randomness(buf, dmi_len);
 145
 146	dmi_early_unmap(buf, orig_dmi_len);
 147	return 0;
 148}
 149
 150static int __init dmi_checksum(const u8 *buf, u8 len)
 151{
 152	u8 sum = 0;
 153	int a;
 154
 155	for (a = 0; a < len; a++)
 156		sum += buf[a];
 157
 158	return sum == 0;
 159}
 160
 161static const char *dmi_ident[DMI_STRING_MAX];
 162static LIST_HEAD(dmi_devices);
 163int dmi_available;
 
 164
 165/*
 166 *	Save a DMI string
 167 */
 168static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
 169		int string)
 170{
 171	const char *d = (const char *) dm;
 172	const char *p;
 173
 174	if (dmi_ident[slot] || dm->length <= string)
 175		return;
 176
 177	p = dmi_string(dm, d[string]);
 178	if (p == NULL)
 179		return;
 180
 181	dmi_ident[slot] = p;
 182}
 183
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 184static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
 185		int index)
 186{
 187	const u8 *d;
 188	char *s;
 189	int is_ff = 1, is_00 = 1, i;
 190
 191	if (dmi_ident[slot] || dm->length < index + 16)
 192		return;
 193
 194	d = (u8 *) dm + index;
 195	for (i = 0; i < 16 && (is_ff || is_00); i++) {
 196		if (d[i] != 0x00)
 197			is_00 = 0;
 198		if (d[i] != 0xFF)
 199			is_ff = 0;
 200	}
 201
 202	if (is_ff || is_00)
 203		return;
 204
 205	s = dmi_alloc(16*2+4+1);
 206	if (!s)
 207		return;
 208
 209	/*
 210	 * As of version 2.6 of the SMBIOS specification, the first 3 fields of
 211	 * the UUID are supposed to be little-endian encoded.  The specification
 212	 * says that this is the defacto standard.
 213	 */
 214	if (dmi_ver >= 0x020600)
 215		sprintf(s, "%pUl", d);
 216	else
 217		sprintf(s, "%pUb", d);
 218
 219	dmi_ident[slot] = s;
 220}
 221
 222static void __init dmi_save_type(const struct dmi_header *dm, int slot,
 223		int index)
 224{
 225	const u8 *d;
 226	char *s;
 227
 228	if (dmi_ident[slot] || dm->length <= index)
 229		return;
 230
 231	s = dmi_alloc(4);
 232	if (!s)
 233		return;
 234
 235	d = (u8 *) dm + index;
 236	sprintf(s, "%u", *d & 0x7F);
 237	dmi_ident[slot] = s;
 238}
 239
 240static void __init dmi_save_one_device(int type, const char *name)
 241{
 242	struct dmi_device *dev;
 243
 244	/* No duplicate device */
 245	if (dmi_find_device(type, name, NULL))
 246		return;
 247
 248	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 249	if (!dev)
 250		return;
 251
 252	dev->type = type;
 253	strcpy((char *)(dev + 1), name);
 254	dev->name = (char *)(dev + 1);
 255	dev->device_data = NULL;
 256	list_add(&dev->list, &dmi_devices);
 257}
 258
 259static void __init dmi_save_devices(const struct dmi_header *dm)
 260{
 261	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
 262
 263	for (i = 0; i < count; i++) {
 264		const char *d = (char *)(dm + 1) + (i * 2);
 265
 266		/* Skip disabled device */
 267		if ((*d & 0x80) == 0)
 268			continue;
 269
 270		dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
 271	}
 272}
 273
 274static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
 275{
 276	int i, count;
 277	struct dmi_device *dev;
 278
 279	if (dm->length < 0x05)
 280		return;
 281
 282	count = *(u8 *)(dm + 1);
 283	for (i = 1; i <= count; i++) {
 284		const char *devname = dmi_string(dm, i);
 285
 286		if (devname == dmi_empty_string)
 287			continue;
 288
 289		dev = dmi_alloc(sizeof(*dev));
 290		if (!dev)
 291			break;
 292
 293		dev->type = DMI_DEV_TYPE_OEM_STRING;
 294		dev->name = devname;
 295		dev->device_data = NULL;
 296
 297		list_add(&dev->list, &dmi_devices);
 298	}
 299}
 300
 301static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
 302{
 303	struct dmi_device *dev;
 304	void *data;
 305
 306	data = dmi_alloc(dm->length);
 307	if (data == NULL)
 308		return;
 309
 310	memcpy(data, dm, dm->length);
 311
 312	dev = dmi_alloc(sizeof(*dev));
 313	if (!dev)
 314		return;
 315
 316	dev->type = DMI_DEV_TYPE_IPMI;
 317	dev->name = "IPMI controller";
 318	dev->device_data = data;
 319
 320	list_add_tail(&dev->list, &dmi_devices);
 321}
 322
 323static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
 324					int devfn, const char *name, int type)
 325{
 326	struct dmi_dev_onboard *dev;
 327
 328	/* Ignore invalid values */
 329	if (type == DMI_DEV_TYPE_DEV_SLOT &&
 330	    segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
 331		return;
 332
 333	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 334	if (!dev)
 335		return;
 336
 337	dev->instance = instance;
 338	dev->segment = segment;
 339	dev->bus = bus;
 340	dev->devfn = devfn;
 341
 342	strcpy((char *)&dev[1], name);
 343	dev->dev.type = type;
 344	dev->dev.name = (char *)&dev[1];
 345	dev->dev.device_data = dev;
 346
 347	list_add(&dev->dev.list, &dmi_devices);
 348}
 349
 350static void __init dmi_save_extended_devices(const struct dmi_header *dm)
 351{
 352	const char *name;
 353	const u8 *d = (u8 *)dm;
 354
 355	if (dm->length < 0x0B)
 356		return;
 357
 358	/* Skip disabled device */
 359	if ((d[0x5] & 0x80) == 0)
 360		return;
 361
 362	name = dmi_string_nosave(dm, d[0x4]);
 363	dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
 364			     DMI_DEV_TYPE_DEV_ONBOARD);
 365	dmi_save_one_device(d[0x5] & 0x7f, name);
 366}
 367
 368static void __init dmi_save_system_slot(const struct dmi_header *dm)
 369{
 370	const u8 *d = (u8 *)dm;
 371
 372	/* Need SMBIOS 2.6+ structure */
 373	if (dm->length < 0x11)
 374		return;
 375	dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
 376			     d[0x10], dmi_string_nosave(dm, d[0x4]),
 377			     DMI_DEV_TYPE_DEV_SLOT);
 378}
 379
 380static void __init count_mem_devices(const struct dmi_header *dm, void *v)
 381{
 382	if (dm->type != DMI_ENTRY_MEM_DEVICE)
 383		return;
 384	dmi_memdev_nr++;
 385}
 386
 387static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 388{
 389	const char *d = (const char *)dm;
 390	static int nr;
 391	u64 bytes;
 392	u16 size;
 393
 394	if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x12)
 395		return;
 396	if (nr >= dmi_memdev_nr) {
 397		pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 398		return;
 399	}
 400	dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 401	dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 402	dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 
 403
 404	size = get_unaligned((u16 *)&d[0xC]);
 405	if (size == 0)
 406		bytes = 0;
 407	else if (size == 0xffff)
 408		bytes = ~0ull;
 409	else if (size & 0x8000)
 410		bytes = (u64)(size & 0x7fff) << 10;
 411	else if (size != 0x7fff || dm->length < 0x20)
 412		bytes = (u64)size << 20;
 413	else
 414		bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
 415
 416	dmi_memdev[nr].size = bytes;
 417	nr++;
 418}
 419
 420static void __init dmi_memdev_walk(void)
 421{
 422	if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
 423		dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
 424		if (dmi_memdev)
 425			dmi_walk_early(save_mem_devices);
 426	}
 427}
 428
 429/*
 430 *	Process a DMI table entry. Right now all we care about are the BIOS
 431 *	and machine entries. For 2.5 we should pull the smbus controller info
 432 *	out of here.
 433 */
 434static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
 435{
 436	switch (dm->type) {
 437	case 0:		/* BIOS Information */
 438		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
 439		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
 440		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
 
 
 441		break;
 442	case 1:		/* System Information */
 443		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
 444		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
 445		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 446		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 447		dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
 448		dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
 449		dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
 450		break;
 451	case 2:		/* Base Board Information */
 452		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
 453		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
 454		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
 455		dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
 456		dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
 457		break;
 458	case 3:		/* Chassis Information */
 459		dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
 460		dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
 461		dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
 462		dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
 463		dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
 464		break;
 465	case 9:		/* System Slots */
 466		dmi_save_system_slot(dm);
 467		break;
 468	case 10:	/* Onboard Devices Information */
 469		dmi_save_devices(dm);
 470		break;
 471	case 11:	/* OEM Strings */
 472		dmi_save_oem_strings_devices(dm);
 473		break;
 474	case 38:	/* IPMI Device Information */
 475		dmi_save_ipmi_device(dm);
 476		break;
 477	case 41:	/* Onboard Devices Extended Information */
 478		dmi_save_extended_devices(dm);
 479	}
 480}
 481
 482static int __init print_filtered(char *buf, size_t len, const char *info)
 483{
 484	int c = 0;
 485	const char *p;
 486
 487	if (!info)
 488		return c;
 489
 490	for (p = info; *p; p++)
 491		if (isprint(*p))
 492			c += scnprintf(buf + c, len - c, "%c", *p);
 493		else
 494			c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
 495	return c;
 496}
 497
 498static void __init dmi_format_ids(char *buf, size_t len)
 499{
 500	int c = 0;
 501	const char *board;	/* Board Name is optional */
 502
 503	c += print_filtered(buf + c, len - c,
 504			    dmi_get_system_info(DMI_SYS_VENDOR));
 505	c += scnprintf(buf + c, len - c, " ");
 506	c += print_filtered(buf + c, len - c,
 507			    dmi_get_system_info(DMI_PRODUCT_NAME));
 508
 509	board = dmi_get_system_info(DMI_BOARD_NAME);
 510	if (board) {
 511		c += scnprintf(buf + c, len - c, "/");
 512		c += print_filtered(buf + c, len - c, board);
 513	}
 514	c += scnprintf(buf + c, len - c, ", BIOS ");
 515	c += print_filtered(buf + c, len - c,
 516			    dmi_get_system_info(DMI_BIOS_VERSION));
 517	c += scnprintf(buf + c, len - c, " ");
 518	c += print_filtered(buf + c, len - c,
 519			    dmi_get_system_info(DMI_BIOS_DATE));
 520}
 521
 522/*
 523 * Check for DMI/SMBIOS headers in the system firmware image.  Any
 524 * SMBIOS header must start 16 bytes before the DMI header, so take a
 525 * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
 526 * 0.  If the DMI header is present, set dmi_ver accordingly (SMBIOS
 527 * takes precedence) and return 0.  Otherwise return 1.
 528 */
 529static int __init dmi_present(const u8 *buf)
 530{
 531	u32 smbios_ver;
 532
 
 
 
 
 533	if (memcmp(buf, "_SM_", 4) == 0 &&
 534	    buf[5] < 32 && dmi_checksum(buf, buf[5])) {
 
 535		smbios_ver = get_unaligned_be16(buf + 6);
 536		smbios_entry_point_size = buf[5];
 537		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 538
 539		/* Some BIOS report weird SMBIOS version, fix that up */
 540		switch (smbios_ver) {
 541		case 0x021F:
 542		case 0x0221:
 543			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
 544				 smbios_ver & 0xFF, 3);
 545			smbios_ver = 0x0203;
 546			break;
 547		case 0x0233:
 548			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
 549			smbios_ver = 0x0206;
 550			break;
 551		}
 552	} else {
 553		smbios_ver = 0;
 554	}
 555
 556	buf += 16;
 557
 558	if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
 559		if (smbios_ver)
 560			dmi_ver = smbios_ver;
 561		else
 562			dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
 563		dmi_ver <<= 8;
 564		dmi_num = get_unaligned_le16(buf + 12);
 565		dmi_len = get_unaligned_le16(buf + 6);
 566		dmi_base = get_unaligned_le32(buf + 8);
 567
 568		if (dmi_walk_early(dmi_decode) == 0) {
 569			if (smbios_ver) {
 570				pr_info("SMBIOS %d.%d present.\n",
 571					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 572			} else {
 573				smbios_entry_point_size = 15;
 574				memcpy(smbios_entry_point, buf,
 575				       smbios_entry_point_size);
 576				pr_info("Legacy DMI %d.%d present.\n",
 577					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 578			}
 579			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 580			pr_info("DMI: %s\n", dmi_ids_string);
 581			return 0;
 582		}
 583	}
 584
 585	return 1;
 586}
 587
 588/*
 589 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
 590 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
 591 */
 592static int __init dmi_smbios3_present(const u8 *buf)
 593{
 594	if (memcmp(buf, "_SM3_", 5) == 0 &&
 595	    buf[6] < 32 && dmi_checksum(buf, buf[6])) {
 596		dmi_ver = get_unaligned_be32(buf + 6) & 0xFFFFFF;
 
 597		dmi_num = 0;			/* No longer specified */
 598		dmi_len = get_unaligned_le32(buf + 12);
 599		dmi_base = get_unaligned_le64(buf + 16);
 600		smbios_entry_point_size = buf[6];
 601		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 602
 603		if (dmi_walk_early(dmi_decode) == 0) {
 604			pr_info("SMBIOS %d.%d.%d present.\n",
 605				dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
 606				dmi_ver & 0xFF);
 607			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 608			pr_info("DMI: %s\n", dmi_ids_string);
 609			return 0;
 610		}
 611	}
 612	return 1;
 613}
 614
 615static void __init dmi_scan_machine(void)
 616{
 617	char __iomem *p, *q;
 618	char buf[32];
 619
 620	if (efi_enabled(EFI_CONFIG_TABLES)) {
 621		/*
 622		 * According to the DMTF SMBIOS reference spec v3.0.0, it is
 623		 * allowed to define both the 64-bit entry point (smbios3) and
 624		 * the 32-bit entry point (smbios), in which case they should
 625		 * either both point to the same SMBIOS structure table, or the
 626		 * table pointed to by the 64-bit entry point should contain a
 627		 * superset of the table contents pointed to by the 32-bit entry
 628		 * point (section 5.2)
 629		 * This implies that the 64-bit entry point should have
 630		 * precedence if it is defined and supported by the OS. If we
 631		 * have the 64-bit entry point, but fail to decode it, fall
 632		 * back to the legacy one (if available)
 633		 */
 634		if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
 635			p = dmi_early_remap(efi.smbios3, 32);
 636			if (p == NULL)
 637				goto error;
 638			memcpy_fromio(buf, p, 32);
 639			dmi_early_unmap(p, 32);
 640
 641			if (!dmi_smbios3_present(buf)) {
 642				dmi_available = 1;
 643				return;
 644			}
 645		}
 646		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 647			goto error;
 648
 649		/* This is called as a core_initcall() because it isn't
 650		 * needed during early boot.  This also means we can
 651		 * iounmap the space when we're done with it.
 652		 */
 653		p = dmi_early_remap(efi.smbios, 32);
 654		if (p == NULL)
 655			goto error;
 656		memcpy_fromio(buf, p, 32);
 657		dmi_early_unmap(p, 32);
 658
 659		if (!dmi_present(buf)) {
 660			dmi_available = 1;
 661			return;
 662		}
 663	} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
 664		p = dmi_early_remap(0xF0000, 0x10000);
 665		if (p == NULL)
 666			goto error;
 667
 668		/*
 669		 * Same logic as above, look for a 64-bit entry point
 670		 * first, and if not found, fall back to 32-bit entry point.
 671		 */
 672		memcpy_fromio(buf, p, 16);
 673		for (q = p + 16; q < p + 0x10000; q += 16) {
 674			memcpy_fromio(buf + 16, q, 16);
 675			if (!dmi_smbios3_present(buf)) {
 676				dmi_available = 1;
 677				dmi_early_unmap(p, 0x10000);
 678				return;
 679			}
 680			memcpy(buf, buf + 16, 16);
 681		}
 682
 683		/*
 684		 * Iterate over all possible DMI header addresses q.
 685		 * Maintain the 32 bytes around q in buf.  On the
 686		 * first iteration, substitute zero for the
 687		 * out-of-range bytes so there is no chance of falsely
 688		 * detecting an SMBIOS header.
 689		 */
 690		memset(buf, 0, 16);
 691		for (q = p; q < p + 0x10000; q += 16) {
 692			memcpy_fromio(buf + 16, q, 16);
 693			if (!dmi_present(buf)) {
 694				dmi_available = 1;
 695				dmi_early_unmap(p, 0x10000);
 696				return;
 697			}
 698			memcpy(buf, buf + 16, 16);
 699		}
 700		dmi_early_unmap(p, 0x10000);
 701	}
 702 error:
 703	pr_info("DMI not present or invalid.\n");
 704}
 705
 706static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
 707			      struct bin_attribute *attr, char *buf,
 708			      loff_t pos, size_t count)
 709{
 710	memcpy(buf, attr->private + pos, count);
 711	return count;
 712}
 713
 714static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
 715static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
 716
 717static int __init dmi_init(void)
 718{
 719	struct kobject *tables_kobj;
 720	u8 *dmi_table;
 721	int ret = -ENOMEM;
 722
 723	if (!dmi_available)
 724		return 0;
 725
 726	/*
 727	 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
 728	 * even after farther error, as it can be used by other modules like
 729	 * dmi-sysfs.
 730	 */
 731	dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
 732	if (!dmi_kobj)
 733		goto err;
 734
 735	tables_kobj = kobject_create_and_add("tables", dmi_kobj);
 736	if (!tables_kobj)
 737		goto err;
 738
 739	dmi_table = dmi_remap(dmi_base, dmi_len);
 740	if (!dmi_table)
 741		goto err_tables;
 742
 743	bin_attr_smbios_entry_point.size = smbios_entry_point_size;
 744	bin_attr_smbios_entry_point.private = smbios_entry_point;
 745	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
 746	if (ret)
 747		goto err_unmap;
 748
 749	bin_attr_DMI.size = dmi_len;
 750	bin_attr_DMI.private = dmi_table;
 751	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
 752	if (!ret)
 753		return 0;
 754
 755	sysfs_remove_bin_file(tables_kobj,
 756			      &bin_attr_smbios_entry_point);
 757 err_unmap:
 758	dmi_unmap(dmi_table);
 759 err_tables:
 760	kobject_del(tables_kobj);
 761	kobject_put(tables_kobj);
 762 err:
 763	pr_err("dmi: Firmware registration failed.\n");
 764
 765	return ret;
 766}
 767subsys_initcall(dmi_init);
 768
 769/**
 770 *	dmi_setup - scan and setup DMI system information
 771 *
 772 *	Scan the DMI system information. This setups DMI identifiers
 773 *	(dmi_system_id) for printing it out on task dumps and prepares
 774 *	DIMM entry information (dmi_memdev_info) from the SMBIOS table
 775 *	for using this when reporting memory errors.
 776 */
 777void __init dmi_setup(void)
 778{
 779	dmi_scan_machine();
 780	if (!dmi_available)
 781		return;
 782
 783	dmi_memdev_walk();
 784	dump_stack_set_arch_desc("%s", dmi_ids_string);
 785}
 786
 787/**
 788 *	dmi_matches - check if dmi_system_id structure matches system DMI data
 789 *	@dmi: pointer to the dmi_system_id structure to check
 790 */
 791static bool dmi_matches(const struct dmi_system_id *dmi)
 792{
 793	int i;
 794
 795	for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
 796		int s = dmi->matches[i].slot;
 797		if (s == DMI_NONE)
 798			break;
 799		if (s == DMI_OEM_STRING) {
 800			/* DMI_OEM_STRING must be exact match */
 801			const struct dmi_device *valid;
 802
 803			valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
 804						dmi->matches[i].substr, NULL);
 805			if (valid)
 806				continue;
 807		} else if (dmi_ident[s]) {
 808			if (dmi->matches[i].exact_match) {
 809				if (!strcmp(dmi_ident[s],
 810					    dmi->matches[i].substr))
 811					continue;
 812			} else {
 813				if (strstr(dmi_ident[s],
 814					   dmi->matches[i].substr))
 815					continue;
 816			}
 817		}
 818
 819		/* No match */
 820		return false;
 821	}
 822	return true;
 823}
 824
 825/**
 826 *	dmi_is_end_of_table - check for end-of-table marker
 827 *	@dmi: pointer to the dmi_system_id structure to check
 828 */
 829static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
 830{
 831	return dmi->matches[0].slot == DMI_NONE;
 832}
 833
 834/**
 835 *	dmi_check_system - check system DMI data
 836 *	@list: array of dmi_system_id structures to match against
 837 *		All non-null elements of the list must match
 838 *		their slot's (field index's) data (i.e., each
 839 *		list string must be a substring of the specified
 840 *		DMI slot's string data) to be considered a
 841 *		successful match.
 842 *
 843 *	Walk the blacklist table running matching functions until someone
 844 *	returns non zero or we hit the end. Callback function is called for
 845 *	each successful match. Returns the number of matches.
 846 *
 847 *	dmi_setup must be called before this function is called.
 848 */
 849int dmi_check_system(const struct dmi_system_id *list)
 850{
 851	int count = 0;
 852	const struct dmi_system_id *d;
 853
 854	for (d = list; !dmi_is_end_of_table(d); d++)
 855		if (dmi_matches(d)) {
 856			count++;
 857			if (d->callback && d->callback(d))
 858				break;
 859		}
 860
 861	return count;
 862}
 863EXPORT_SYMBOL(dmi_check_system);
 864
 865/**
 866 *	dmi_first_match - find dmi_system_id structure matching system DMI data
 867 *	@list: array of dmi_system_id structures to match against
 868 *		All non-null elements of the list must match
 869 *		their slot's (field index's) data (i.e., each
 870 *		list string must be a substring of the specified
 871 *		DMI slot's string data) to be considered a
 872 *		successful match.
 873 *
 874 *	Walk the blacklist table until the first match is found.  Return the
 875 *	pointer to the matching entry or NULL if there's no match.
 876 *
 877 *	dmi_setup must be called before this function is called.
 878 */
 879const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 880{
 881	const struct dmi_system_id *d;
 882
 883	for (d = list; !dmi_is_end_of_table(d); d++)
 884		if (dmi_matches(d))
 885			return d;
 886
 887	return NULL;
 888}
 889EXPORT_SYMBOL(dmi_first_match);
 890
 891/**
 892 *	dmi_get_system_info - return DMI data value
 893 *	@field: data index (see enum dmi_field)
 894 *
 895 *	Returns one DMI data value, can be used to perform
 896 *	complex DMI data checks.
 897 */
 898const char *dmi_get_system_info(int field)
 899{
 900	return dmi_ident[field];
 901}
 902EXPORT_SYMBOL(dmi_get_system_info);
 903
 904/**
 905 * dmi_name_in_serial - Check if string is in the DMI product serial information
 906 * @str: string to check for
 907 */
 908int dmi_name_in_serial(const char *str)
 909{
 910	int f = DMI_PRODUCT_SERIAL;
 911	if (dmi_ident[f] && strstr(dmi_ident[f], str))
 912		return 1;
 913	return 0;
 914}
 915
 916/**
 917 *	dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
 918 *	@str: Case sensitive Name
 919 */
 920int dmi_name_in_vendors(const char *str)
 921{
 922	static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 923	int i;
 924	for (i = 0; fields[i] != DMI_NONE; i++) {
 925		int f = fields[i];
 926		if (dmi_ident[f] && strstr(dmi_ident[f], str))
 927			return 1;
 928	}
 929	return 0;
 930}
 931EXPORT_SYMBOL(dmi_name_in_vendors);
 932
 933/**
 934 *	dmi_find_device - find onboard device by type/name
 935 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 936 *	@name: device name string or %NULL to match all
 937 *	@from: previous device found in search, or %NULL for new search.
 938 *
 939 *	Iterates through the list of known onboard devices. If a device is
 940 *	found with a matching @type and @name, a pointer to its device
 941 *	structure is returned.  Otherwise, %NULL is returned.
 942 *	A new search is initiated by passing %NULL as the @from argument.
 943 *	If @from is not %NULL, searches continue from next device.
 944 */
 945const struct dmi_device *dmi_find_device(int type, const char *name,
 946				    const struct dmi_device *from)
 947{
 948	const struct list_head *head = from ? &from->list : &dmi_devices;
 949	struct list_head *d;
 950
 951	for (d = head->next; d != &dmi_devices; d = d->next) {
 952		const struct dmi_device *dev =
 953			list_entry(d, struct dmi_device, list);
 954
 955		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
 956		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
 957			return dev;
 958	}
 959
 960	return NULL;
 961}
 962EXPORT_SYMBOL(dmi_find_device);
 963
 964/**
 965 *	dmi_get_date - parse a DMI date
 966 *	@field:	data index (see enum dmi_field)
 967 *	@yearp: optional out parameter for the year
 968 *	@monthp: optional out parameter for the month
 969 *	@dayp: optional out parameter for the day
 970 *
 971 *	The date field is assumed to be in the form resembling
 972 *	[mm[/dd]]/yy[yy] and the result is stored in the out
 973 *	parameters any or all of which can be omitted.
 974 *
 975 *	If the field doesn't exist, all out parameters are set to zero
 976 *	and false is returned.  Otherwise, true is returned with any
 977 *	invalid part of date set to zero.
 978 *
 979 *	On return, year, month and day are guaranteed to be in the
 980 *	range of [0,9999], [0,12] and [0,31] respectively.
 981 */
 982bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
 983{
 984	int year = 0, month = 0, day = 0;
 985	bool exists;
 986	const char *s, *y;
 987	char *e;
 988
 989	s = dmi_get_system_info(field);
 990	exists = s;
 991	if (!exists)
 992		goto out;
 993
 994	/*
 995	 * Determine year first.  We assume the date string resembles
 996	 * mm/dd/yy[yy] but the original code extracted only the year
 997	 * from the end.  Keep the behavior in the spirit of no
 998	 * surprises.
 999	 */
1000	y = strrchr(s, '/');
1001	if (!y)
1002		goto out;
1003
1004	y++;
1005	year = simple_strtoul(y, &e, 10);
1006	if (y != e && year < 100) {	/* 2-digit year */
1007		year += 1900;
1008		if (year < 1996)	/* no dates < spec 1.0 */
1009			year += 100;
1010	}
1011	if (year > 9999)		/* year should fit in %04d */
1012		year = 0;
1013
1014	/* parse the mm and dd */
1015	month = simple_strtoul(s, &e, 10);
1016	if (s == e || *e != '/' || !month || month > 12) {
1017		month = 0;
1018		goto out;
1019	}
1020
1021	s = e + 1;
1022	day = simple_strtoul(s, &e, 10);
1023	if (s == y || s == e || *e != '/' || day > 31)
1024		day = 0;
1025out:
1026	if (yearp)
1027		*yearp = year;
1028	if (monthp)
1029		*monthp = month;
1030	if (dayp)
1031		*dayp = day;
1032	return exists;
1033}
1034EXPORT_SYMBOL(dmi_get_date);
1035
1036/**
1037 *	dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1038 *
1039 *	Returns year on success, -ENXIO if DMI is not selected,
1040 *	or a different negative error code if DMI field is not present
1041 *	or not parseable.
1042 */
1043int dmi_get_bios_year(void)
1044{
1045	bool exists;
1046	int year;
1047
1048	exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1049	if (!exists)
1050		return -ENODATA;
1051
1052	return year ? year : -ERANGE;
1053}
1054EXPORT_SYMBOL(dmi_get_bios_year);
1055
1056/**
1057 *	dmi_walk - Walk the DMI table and get called back for every record
1058 *	@decode: Callback function
1059 *	@private_data: Private data to be passed to the callback function
1060 *
1061 *	Returns 0 on success, -ENXIO if DMI is not selected or not present,
1062 *	or a different negative error code if DMI walking fails.
1063 */
1064int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1065	     void *private_data)
1066{
1067	u8 *buf;
1068
1069	if (!dmi_available)
1070		return -ENXIO;
1071
1072	buf = dmi_remap(dmi_base, dmi_len);
1073	if (buf == NULL)
1074		return -ENOMEM;
1075
1076	dmi_decode_table(buf, decode, private_data);
1077
1078	dmi_unmap(buf);
1079	return 0;
1080}
1081EXPORT_SYMBOL_GPL(dmi_walk);
1082
1083/**
1084 * dmi_match - compare a string to the dmi field (if exists)
1085 * @f: DMI field identifier
1086 * @str: string to compare the DMI field to
1087 *
1088 * Returns true if the requested field equals to the str (including NULL).
1089 */
1090bool dmi_match(enum dmi_field f, const char *str)
1091{
1092	const char *info = dmi_get_system_info(f);
1093
1094	if (info == NULL || str == NULL)
1095		return info == str;
1096
1097	return !strcmp(info, str);
1098}
1099EXPORT_SYMBOL_GPL(dmi_match);
1100
1101void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1102{
1103	int n;
1104
1105	if (dmi_memdev == NULL)
1106		return;
1107
1108	for (n = 0; n < dmi_memdev_nr; n++) {
1109		if (handle == dmi_memdev[n].handle) {
1110			*bank = dmi_memdev[n].bank;
1111			*device = dmi_memdev[n].device;
1112			break;
1113		}
1114	}
1115}
1116EXPORT_SYMBOL_GPL(dmi_memdev_name);
1117
1118u64 dmi_memdev_size(u16 handle)
1119{
1120	int n;
1121
1122	if (dmi_memdev) {
1123		for (n = 0; n < dmi_memdev_nr; n++) {
1124			if (handle == dmi_memdev[n].handle)
1125				return dmi_memdev[n].size;
1126		}
1127	}
1128	return ~0ull;
1129}
1130EXPORT_SYMBOL_GPL(dmi_memdev_size);