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v6.13.7
   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 <linux/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;
  45static int dmi_memdev_populated_nr __initdata;
  46
  47static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
  48{
  49	const u8 *bp = ((u8 *) dm) + dm->length;
  50	const u8 *nsp;
  51
  52	if (s) {
  53		while (--s > 0 && *bp)
  54			bp += strlen(bp) + 1;
  55
  56		/* Strings containing only spaces are considered empty */
  57		nsp = bp;
  58		while (*nsp == ' ')
  59			nsp++;
  60		if (*nsp != '\0')
  61			return bp;
  62	}
  63
  64	return dmi_empty_string;
  65}
  66
  67static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  68{
  69	const char *bp = dmi_string_nosave(dm, s);
  70	char *str;
  71	size_t len;
  72
  73	if (bp == dmi_empty_string)
  74		return dmi_empty_string;
  75
  76	len = strlen(bp) + 1;
  77	str = dmi_alloc(len);
  78	if (str != NULL)
  79		strcpy(str, bp);
  80
  81	return str;
  82}
  83
  84/*
  85 *	We have to be cautious here. We have seen BIOSes with DMI pointers
  86 *	pointing to completely the wrong place for example
  87 */
  88static void dmi_decode_table(u8 *buf,
  89			     void (*decode)(const struct dmi_header *, void *),
  90			     void *private_data)
  91{
  92	u8 *data = buf;
  93	int i = 0;
  94
  95	/*
  96	 * Stop when we have seen all the items the table claimed to have
  97	 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
  98	 * >= 3.0 only) OR we run off the end of the table (should never
  99	 * happen but sometimes does on bogus implementations.)
 100	 */
 101	while ((!dmi_num || i < dmi_num) &&
 102	       (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
 103		const struct dmi_header *dm = (const struct dmi_header *)data;
 104
 105		/*
 106		 * If a short entry is found (less than 4 bytes), not only it
 107		 * is invalid, but we cannot reliably locate the next entry.
 108		 */
 109		if (dm->length < sizeof(struct dmi_header)) {
 110			pr_warn(FW_BUG
 111				"Corrupted DMI table, offset %zd (only %d entries processed)\n",
 112				data - buf, i);
 113			break;
 114		}
 115
 116		/*
 117		 *  We want to know the total length (formatted area and
 118		 *  strings) before decoding to make sure we won't run off the
 119		 *  table in dmi_decode or dmi_string
 120		 */
 121		data += dm->length;
 122		while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
 123			data++;
 124		if (data - buf < dmi_len - 1)
 125			decode(dm, private_data);
 126
 127		data += 2;
 128		i++;
 129
 130		/*
 131		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
 132		 * For tables behind a 64-bit entry point, we have no item
 133		 * count and no exact table length, so stop on end-of-table
 134		 * marker. For tables behind a 32-bit entry point, we have
 135		 * seen OEM structures behind the end-of-table marker on
 136		 * some systems, so don't trust it.
 137		 */
 138		if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
 139			break;
 140	}
 141
 142	/* Trim DMI table length if needed */
 143	if (dmi_len > data - buf)
 144		dmi_len = data - buf;
 145}
 146
 147static phys_addr_t dmi_base;
 148
 149static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
 150		void *))
 151{
 152	u8 *buf;
 153	u32 orig_dmi_len = dmi_len;
 154
 155	buf = dmi_early_remap(dmi_base, orig_dmi_len);
 156	if (buf == NULL)
 157		return -ENOMEM;
 158
 159	dmi_decode_table(buf, decode, NULL);
 160
 161	add_device_randomness(buf, dmi_len);
 162
 163	dmi_early_unmap(buf, orig_dmi_len);
 164	return 0;
 165}
 166
 167static int __init dmi_checksum(const u8 *buf, u8 len)
 168{
 169	u8 sum = 0;
 170	int a;
 171
 172	for (a = 0; a < len; a++)
 173		sum += buf[a];
 174
 175	return sum == 0;
 176}
 177
 178static const char *dmi_ident[DMI_STRING_MAX];
 179static LIST_HEAD(dmi_devices);
 180int dmi_available;
 181EXPORT_SYMBOL_GPL(dmi_available);
 182
 183/*
 184 *	Save a DMI string
 185 */
 186static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
 187		int string)
 188{
 189	const char *d = (const char *) dm;
 190	const char *p;
 191
 192	if (dmi_ident[slot] || dm->length <= string)
 193		return;
 194
 195	p = dmi_string(dm, d[string]);
 196	if (p == NULL)
 197		return;
 198
 199	dmi_ident[slot] = p;
 200}
 201
 202static void __init dmi_save_release(const struct dmi_header *dm, int slot,
 203		int index)
 204{
 205	const u8 *minor, *major;
 206	char *s;
 207
 208	/* If the table doesn't have the field, let's return */
 209	if (dmi_ident[slot] || dm->length < index)
 210		return;
 211
 212	minor = (u8 *) dm + index;
 213	major = (u8 *) dm + index - 1;
 214
 215	/* As per the spec, if the system doesn't support this field,
 216	 * the value is FF
 217	 */
 218	if (*major == 0xFF && *minor == 0xFF)
 219		return;
 220
 221	s = dmi_alloc(8);
 222	if (!s)
 223		return;
 224
 225	sprintf(s, "%u.%u", *major, *minor);
 226
 227	dmi_ident[slot] = s;
 228}
 229
 230static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
 231		int index)
 232{
 233	const u8 *d;
 234	char *s;
 235	int is_ff = 1, is_00 = 1, i;
 236
 237	if (dmi_ident[slot] || dm->length < index + 16)
 238		return;
 239
 240	d = (u8 *) dm + index;
 241	for (i = 0; i < 16 && (is_ff || is_00); i++) {
 242		if (d[i] != 0x00)
 243			is_00 = 0;
 244		if (d[i] != 0xFF)
 245			is_ff = 0;
 246	}
 247
 248	if (is_ff || is_00)
 249		return;
 250
 251	s = dmi_alloc(16*2+4+1);
 252	if (!s)
 253		return;
 254
 255	/*
 256	 * As of version 2.6 of the SMBIOS specification, the first 3 fields of
 257	 * the UUID are supposed to be little-endian encoded.  The specification
 258	 * says that this is the defacto standard.
 259	 */
 260	if (dmi_ver >= 0x020600)
 261		sprintf(s, "%pUl", d);
 262	else
 263		sprintf(s, "%pUb", d);
 264
 265	dmi_ident[slot] = s;
 266}
 267
 268static void __init dmi_save_type(const struct dmi_header *dm, int slot,
 269		int index)
 270{
 271	const u8 *d;
 272	char *s;
 273
 274	if (dmi_ident[slot] || dm->length <= index)
 275		return;
 276
 277	s = dmi_alloc(4);
 278	if (!s)
 279		return;
 280
 281	d = (u8 *) dm + index;
 282	sprintf(s, "%u", *d & 0x7F);
 283	dmi_ident[slot] = s;
 284}
 285
 286static void __init dmi_save_one_device(int type, const char *name)
 287{
 288	struct dmi_device *dev;
 289
 290	/* No duplicate device */
 291	if (dmi_find_device(type, name, NULL))
 292		return;
 293
 294	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 295	if (!dev)
 296		return;
 297
 298	dev->type = type;
 299	strcpy((char *)(dev + 1), name);
 300	dev->name = (char *)(dev + 1);
 301	dev->device_data = NULL;
 302	list_add(&dev->list, &dmi_devices);
 303}
 304
 305static void __init dmi_save_devices(const struct dmi_header *dm)
 306{
 307	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
 308
 309	for (i = 0; i < count; i++) {
 310		const char *d = (char *)(dm + 1) + (i * 2);
 311
 312		/* Skip disabled device */
 313		if ((*d & 0x80) == 0)
 314			continue;
 315
 316		dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
 317	}
 318}
 319
 320static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
 321{
 322	int i, count;
 323	struct dmi_device *dev;
 324
 325	if (dm->length < 0x05)
 326		return;
 327
 328	count = *(u8 *)(dm + 1);
 329	for (i = 1; i <= count; i++) {
 330		const char *devname = dmi_string(dm, i);
 331
 332		if (devname == dmi_empty_string)
 333			continue;
 334
 335		dev = dmi_alloc(sizeof(*dev));
 336		if (!dev)
 337			break;
 338
 339		dev->type = DMI_DEV_TYPE_OEM_STRING;
 340		dev->name = devname;
 341		dev->device_data = NULL;
 342
 343		list_add(&dev->list, &dmi_devices);
 344	}
 345}
 346
 347static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
 348{
 349	struct dmi_device *dev;
 350	void *data;
 351
 352	data = dmi_alloc(dm->length);
 353	if (data == NULL)
 354		return;
 355
 356	memcpy(data, dm, dm->length);
 357
 358	dev = dmi_alloc(sizeof(*dev));
 359	if (!dev)
 360		return;
 361
 362	dev->type = DMI_DEV_TYPE_IPMI;
 363	dev->name = "IPMI controller";
 364	dev->device_data = data;
 365
 366	list_add_tail(&dev->list, &dmi_devices);
 367}
 368
 369static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
 370					int devfn, const char *name, int type)
 371{
 372	struct dmi_dev_onboard *dev;
 373
 374	/* Ignore invalid values */
 375	if (type == DMI_DEV_TYPE_DEV_SLOT &&
 376	    segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
 377		return;
 378
 379	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 380	if (!dev)
 381		return;
 382
 383	dev->instance = instance;
 384	dev->segment = segment;
 385	dev->bus = bus;
 386	dev->devfn = devfn;
 387
 388	strcpy((char *)&dev[1], name);
 389	dev->dev.type = type;
 390	dev->dev.name = (char *)&dev[1];
 391	dev->dev.device_data = dev;
 392
 393	list_add(&dev->dev.list, &dmi_devices);
 394}
 395
 396static void __init dmi_save_extended_devices(const struct dmi_header *dm)
 397{
 398	const char *name;
 399	const u8 *d = (u8 *)dm;
 400
 401	if (dm->length < 0x0B)
 402		return;
 403
 404	/* Skip disabled device */
 405	if ((d[0x5] & 0x80) == 0)
 406		return;
 407
 408	name = dmi_string_nosave(dm, d[0x4]);
 409	dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
 410			     DMI_DEV_TYPE_DEV_ONBOARD);
 411	dmi_save_one_device(d[0x5] & 0x7f, name);
 412}
 413
 414static void __init dmi_save_system_slot(const struct dmi_header *dm)
 415{
 416	const u8 *d = (u8 *)dm;
 417
 418	/* Need SMBIOS 2.6+ structure */
 419	if (dm->length < 0x11)
 420		return;
 421	dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
 422			     d[0x10], dmi_string_nosave(dm, d[0x4]),
 423			     DMI_DEV_TYPE_DEV_SLOT);
 424}
 425
 426static void __init count_mem_devices(const struct dmi_header *dm, void *v)
 427{
 428	if (dm->type != DMI_ENTRY_MEM_DEVICE)
 429		return;
 430	dmi_memdev_nr++;
 431}
 432
 433static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 434{
 435	const char *d = (const char *)dm;
 436	static int nr;
 437	u64 bytes;
 438	u16 size;
 439
 440	if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x13)
 441		return;
 442	if (nr >= dmi_memdev_nr) {
 443		pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 444		return;
 445	}
 446	dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 447	dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 448	dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 449	dmi_memdev[nr].type = d[0x12];
 450
 451	size = get_unaligned((u16 *)&d[0xC]);
 452	if (size == 0)
 453		bytes = 0;
 454	else if (size == 0xffff)
 455		bytes = ~0ull;
 456	else if (size & 0x8000)
 457		bytes = (u64)(size & 0x7fff) << 10;
 458	else if (size != 0x7fff || dm->length < 0x20)
 459		bytes = (u64)size << 20;
 460	else
 461		bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
 462
 463	if (bytes)
 464		dmi_memdev_populated_nr++;
 465
 466	dmi_memdev[nr].size = bytes;
 467	nr++;
 468}
 469
 470static void __init dmi_memdev_walk(void)
 471{
 472	if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
 473		dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
 474		if (dmi_memdev)
 475			dmi_walk_early(save_mem_devices);
 476	}
 477}
 478
 479/*
 480 *	Process a DMI table entry. Right now all we care about are the BIOS
 481 *	and machine entries. For 2.5 we should pull the smbus controller info
 482 *	out of here.
 483 */
 484static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
 485{
 486	switch (dm->type) {
 487	case 0:		/* BIOS Information */
 488		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
 489		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
 490		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
 491		dmi_save_release(dm, DMI_BIOS_RELEASE, 21);
 492		dmi_save_release(dm, DMI_EC_FIRMWARE_RELEASE, 23);
 493		break;
 494	case 1:		/* System Information */
 495		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
 496		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
 497		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 498		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 499		dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
 500		dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
 501		dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
 502		break;
 503	case 2:		/* Base Board Information */
 504		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
 505		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
 506		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
 507		dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
 508		dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
 509		break;
 510	case 3:		/* Chassis Information */
 511		dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
 512		dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
 513		dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
 514		dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
 515		dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
 516		break;
 517	case 9:		/* System Slots */
 518		dmi_save_system_slot(dm);
 519		break;
 520	case 10:	/* Onboard Devices Information */
 521		dmi_save_devices(dm);
 522		break;
 523	case 11:	/* OEM Strings */
 524		dmi_save_oem_strings_devices(dm);
 525		break;
 526	case 38:	/* IPMI Device Information */
 527		dmi_save_ipmi_device(dm);
 528		break;
 529	case 41:	/* Onboard Devices Extended Information */
 530		dmi_save_extended_devices(dm);
 531	}
 532}
 533
 534static int __init print_filtered(char *buf, size_t len, const char *info)
 535{
 536	int c = 0;
 537	const char *p;
 538
 539	if (!info)
 540		return c;
 541
 542	for (p = info; *p; p++)
 543		if (isprint(*p))
 544			c += scnprintf(buf + c, len - c, "%c", *p);
 545		else
 546			c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
 547	return c;
 548}
 549
 550static void __init dmi_format_ids(char *buf, size_t len)
 551{
 552	int c = 0;
 553	const char *board;	/* Board Name is optional */
 554
 555	c += print_filtered(buf + c, len - c,
 556			    dmi_get_system_info(DMI_SYS_VENDOR));
 557	c += scnprintf(buf + c, len - c, " ");
 558	c += print_filtered(buf + c, len - c,
 559			    dmi_get_system_info(DMI_PRODUCT_NAME));
 560
 561	board = dmi_get_system_info(DMI_BOARD_NAME);
 562	if (board) {
 563		c += scnprintf(buf + c, len - c, "/");
 564		c += print_filtered(buf + c, len - c, board);
 565	}
 566	c += scnprintf(buf + c, len - c, ", BIOS ");
 567	c += print_filtered(buf + c, len - c,
 568			    dmi_get_system_info(DMI_BIOS_VERSION));
 569	c += scnprintf(buf + c, len - c, " ");
 570	c += print_filtered(buf + c, len - c,
 571			    dmi_get_system_info(DMI_BIOS_DATE));
 572}
 573
 574/*
 575 * Check for DMI/SMBIOS headers in the system firmware image.  Any
 576 * SMBIOS header must start 16 bytes before the DMI header, so take a
 577 * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
 578 * 0.  If the DMI header is present, set dmi_ver accordingly (SMBIOS
 579 * takes precedence) and return 0.  Otherwise return 1.
 580 */
 581static int __init dmi_present(const u8 *buf)
 582{
 583	u32 smbios_ver;
 584
 585	/*
 586	 * The size of this structure is 31 bytes, but we also accept value
 587	 * 30 due to a mistake in SMBIOS specification version 2.1.
 588	 */
 589	if (memcmp(buf, "_SM_", 4) == 0 &&
 590	    buf[5] >= 30 && buf[5] <= 32 &&
 591	    dmi_checksum(buf, buf[5])) {
 592		smbios_ver = get_unaligned_be16(buf + 6);
 593		smbios_entry_point_size = buf[5];
 594		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 595
 596		/* Some BIOS report weird SMBIOS version, fix that up */
 597		switch (smbios_ver) {
 598		case 0x021F:
 599		case 0x0221:
 600			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
 601				 smbios_ver & 0xFF, 3);
 602			smbios_ver = 0x0203;
 603			break;
 604		case 0x0233:
 605			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
 606			smbios_ver = 0x0206;
 607			break;
 608		}
 609	} else {
 610		smbios_ver = 0;
 611	}
 612
 613	buf += 16;
 614
 615	if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
 616		if (smbios_ver)
 617			dmi_ver = smbios_ver;
 618		else
 619			dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
 620		dmi_ver <<= 8;
 621		dmi_num = get_unaligned_le16(buf + 12);
 622		dmi_len = get_unaligned_le16(buf + 6);
 623		dmi_base = get_unaligned_le32(buf + 8);
 624
 625		if (dmi_walk_early(dmi_decode) == 0) {
 626			if (smbios_ver) {
 627				pr_info("SMBIOS %d.%d present.\n",
 628					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 629			} else {
 630				smbios_entry_point_size = 15;
 631				memcpy(smbios_entry_point, buf,
 632				       smbios_entry_point_size);
 633				pr_info("Legacy DMI %d.%d present.\n",
 634					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 635			}
 636			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 637			pr_info("DMI: %s\n", dmi_ids_string);
 638			return 0;
 639		}
 640	}
 641
 642	return 1;
 643}
 644
 645/*
 646 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
 647 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
 648 */
 649static int __init dmi_smbios3_present(const u8 *buf)
 650{
 651	if (memcmp(buf, "_SM3_", 5) == 0 &&
 652	    buf[6] >= 24 && buf[6] <= 32 &&
 653	    dmi_checksum(buf, buf[6])) {
 654		dmi_ver = get_unaligned_be24(buf + 7);
 655		dmi_num = 0;			/* No longer specified */
 656		dmi_len = get_unaligned_le32(buf + 12);
 657		dmi_base = get_unaligned_le64(buf + 16);
 658		smbios_entry_point_size = buf[6];
 659		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 660
 661		if (dmi_walk_early(dmi_decode) == 0) {
 662			pr_info("SMBIOS %d.%d.%d present.\n",
 663				dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
 664				dmi_ver & 0xFF);
 665			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 666			pr_info("DMI: %s\n", dmi_ids_string);
 667			return 0;
 668		}
 669	}
 670	return 1;
 671}
 672
 673static void __init dmi_scan_machine(void)
 674{
 675	char __iomem *p, *q;
 676	char buf[32];
 677
 678	if (efi_enabled(EFI_CONFIG_TABLES)) {
 679		/*
 680		 * According to the DMTF SMBIOS reference spec v3.0.0, it is
 681		 * allowed to define both the 64-bit entry point (smbios3) and
 682		 * the 32-bit entry point (smbios), in which case they should
 683		 * either both point to the same SMBIOS structure table, or the
 684		 * table pointed to by the 64-bit entry point should contain a
 685		 * superset of the table contents pointed to by the 32-bit entry
 686		 * point (section 5.2)
 687		 * This implies that the 64-bit entry point should have
 688		 * precedence if it is defined and supported by the OS. If we
 689		 * have the 64-bit entry point, but fail to decode it, fall
 690		 * back to the legacy one (if available)
 691		 */
 692		if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
 693			p = dmi_early_remap(efi.smbios3, 32);
 694			if (p == NULL)
 695				goto error;
 696			memcpy_fromio(buf, p, 32);
 697			dmi_early_unmap(p, 32);
 698
 699			if (!dmi_smbios3_present(buf)) {
 700				dmi_available = 1;
 701				return;
 702			}
 703		}
 704		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 705			goto error;
 706
 707		/* This is called as a core_initcall() because it isn't
 708		 * needed during early boot.  This also means we can
 709		 * iounmap the space when we're done with it.
 710		 */
 711		p = dmi_early_remap(efi.smbios, 32);
 712		if (p == NULL)
 713			goto error;
 714		memcpy_fromio(buf, p, 32);
 715		dmi_early_unmap(p, 32);
 716
 717		if (!dmi_present(buf)) {
 718			dmi_available = 1;
 719			return;
 720		}
 721	} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
 722		p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
 723		if (p == NULL)
 724			goto error;
 725
 726		/*
 727		 * Same logic as above, look for a 64-bit entry point
 728		 * first, and if not found, fall back to 32-bit entry point.
 729		 */
 730		memcpy_fromio(buf, p, 16);
 731		for (q = p + 16; q < p + 0x10000; q += 16) {
 732			memcpy_fromio(buf + 16, q, 16);
 733			if (!dmi_smbios3_present(buf)) {
 734				dmi_available = 1;
 735				dmi_early_unmap(p, 0x10000);
 736				return;
 737			}
 738			memcpy(buf, buf + 16, 16);
 739		}
 740
 741		/*
 742		 * Iterate over all possible DMI header addresses q.
 743		 * Maintain the 32 bytes around q in buf.  On the
 744		 * first iteration, substitute zero for the
 745		 * out-of-range bytes so there is no chance of falsely
 746		 * detecting an SMBIOS header.
 747		 */
 748		memset(buf, 0, 16);
 749		for (q = p; q < p + 0x10000; q += 16) {
 750			memcpy_fromio(buf + 16, q, 16);
 751			if (!dmi_present(buf)) {
 752				dmi_available = 1;
 753				dmi_early_unmap(p, 0x10000);
 754				return;
 755			}
 756			memcpy(buf, buf + 16, 16);
 757		}
 758		dmi_early_unmap(p, 0x10000);
 759	}
 760 error:
 761	pr_info("DMI not present or invalid.\n");
 762}
 763
 764static BIN_ATTR_SIMPLE_ADMIN_RO(smbios_entry_point);
 765static BIN_ATTR_SIMPLE_ADMIN_RO(DMI);
 
 
 
 
 
 
 
 
 766
 767static int __init dmi_init(void)
 768{
 769	struct kobject *tables_kobj;
 770	u8 *dmi_table;
 771	int ret = -ENOMEM;
 772
 773	if (!dmi_available)
 774		return 0;
 775
 776	/*
 777	 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
 778	 * even after farther error, as it can be used by other modules like
 779	 * dmi-sysfs.
 780	 */
 781	dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
 782	if (!dmi_kobj)
 783		goto err;
 784
 785	tables_kobj = kobject_create_and_add("tables", dmi_kobj);
 786	if (!tables_kobj)
 787		goto err;
 788
 789	dmi_table = dmi_remap(dmi_base, dmi_len);
 790	if (!dmi_table)
 791		goto err_tables;
 792
 793	bin_attr_smbios_entry_point.size = smbios_entry_point_size;
 794	bin_attr_smbios_entry_point.private = smbios_entry_point;
 795	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
 796	if (ret)
 797		goto err_unmap;
 798
 799	bin_attr_DMI.size = dmi_len;
 800	bin_attr_DMI.private = dmi_table;
 801	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
 802	if (!ret)
 803		return 0;
 804
 805	sysfs_remove_bin_file(tables_kobj,
 806			      &bin_attr_smbios_entry_point);
 807 err_unmap:
 808	dmi_unmap(dmi_table);
 809 err_tables:
 810	kobject_del(tables_kobj);
 811	kobject_put(tables_kobj);
 812 err:
 813	pr_err("dmi: Firmware registration failed.\n");
 814
 815	return ret;
 816}
 817subsys_initcall(dmi_init);
 818
 819/**
 820 *	dmi_setup - scan and setup DMI system information
 821 *
 822 *	Scan the DMI system information. This setups DMI identifiers
 823 *	(dmi_system_id) for printing it out on task dumps and prepares
 824 *	DIMM entry information (dmi_memdev_info) from the SMBIOS table
 825 *	for using this when reporting memory errors.
 826 */
 827void __init dmi_setup(void)
 828{
 829	dmi_scan_machine();
 830	if (!dmi_available)
 831		return;
 832
 833	dmi_memdev_walk();
 834	pr_info("DMI: Memory slots populated: %d/%d\n",
 835		dmi_memdev_populated_nr, dmi_memdev_nr);
 836	dump_stack_set_arch_desc("%s", dmi_ids_string);
 837}
 838
 839/**
 840 *	dmi_matches - check if dmi_system_id structure matches system DMI data
 841 *	@dmi: pointer to the dmi_system_id structure to check
 842 */
 843static bool dmi_matches(const struct dmi_system_id *dmi)
 844{
 845	int i;
 846
 847	for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
 848		int s = dmi->matches[i].slot;
 849		if (s == DMI_NONE)
 850			break;
 851		if (s == DMI_OEM_STRING) {
 852			/* DMI_OEM_STRING must be exact match */
 853			const struct dmi_device *valid;
 854
 855			valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
 856						dmi->matches[i].substr, NULL);
 857			if (valid)
 858				continue;
 859		} else if (dmi_ident[s]) {
 860			if (dmi->matches[i].exact_match) {
 861				if (!strcmp(dmi_ident[s],
 862					    dmi->matches[i].substr))
 863					continue;
 864			} else {
 865				if (strstr(dmi_ident[s],
 866					   dmi->matches[i].substr))
 867					continue;
 868			}
 869		}
 870
 871		/* No match */
 872		return false;
 873	}
 874	return true;
 875}
 876
 877/**
 878 *	dmi_is_end_of_table - check for end-of-table marker
 879 *	@dmi: pointer to the dmi_system_id structure to check
 880 */
 881static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
 882{
 883	return dmi->matches[0].slot == DMI_NONE;
 884}
 885
 886/**
 887 *	dmi_check_system - check system DMI data
 888 *	@list: array of dmi_system_id structures to match against
 889 *		All non-null elements of the list must match
 890 *		their slot's (field index's) data (i.e., each
 891 *		list string must be a substring of the specified
 892 *		DMI slot's string data) to be considered a
 893 *		successful match.
 894 *
 895 *	Walk the blacklist table running matching functions until someone
 896 *	returns non zero or we hit the end. Callback function is called for
 897 *	each successful match. Returns the number of matches.
 898 *
 899 *	dmi_setup must be called before this function is called.
 900 */
 901int dmi_check_system(const struct dmi_system_id *list)
 902{
 903	int count = 0;
 904	const struct dmi_system_id *d;
 905
 906	for (d = list; !dmi_is_end_of_table(d); d++)
 907		if (dmi_matches(d)) {
 908			count++;
 909			if (d->callback && d->callback(d))
 910				break;
 911		}
 912
 913	return count;
 914}
 915EXPORT_SYMBOL(dmi_check_system);
 916
 917/**
 918 *	dmi_first_match - find dmi_system_id structure matching system DMI data
 919 *	@list: array of dmi_system_id structures to match against
 920 *		All non-null elements of the list must match
 921 *		their slot's (field index's) data (i.e., each
 922 *		list string must be a substring of the specified
 923 *		DMI slot's string data) to be considered a
 924 *		successful match.
 925 *
 926 *	Walk the blacklist table until the first match is found.  Return the
 927 *	pointer to the matching entry or NULL if there's no match.
 928 *
 929 *	dmi_setup must be called before this function is called.
 930 */
 931const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 932{
 933	const struct dmi_system_id *d;
 934
 935	for (d = list; !dmi_is_end_of_table(d); d++)
 936		if (dmi_matches(d))
 937			return d;
 938
 939	return NULL;
 940}
 941EXPORT_SYMBOL(dmi_first_match);
 942
 943/**
 944 *	dmi_get_system_info - return DMI data value
 945 *	@field: data index (see enum dmi_field)
 946 *
 947 *	Returns one DMI data value, can be used to perform
 948 *	complex DMI data checks.
 949 */
 950const char *dmi_get_system_info(int field)
 951{
 952	return dmi_ident[field];
 953}
 954EXPORT_SYMBOL(dmi_get_system_info);
 955
 956/**
 957 * dmi_name_in_serial - Check if string is in the DMI product serial information
 958 * @str: string to check for
 959 */
 960int dmi_name_in_serial(const char *str)
 961{
 962	int f = DMI_PRODUCT_SERIAL;
 963	if (dmi_ident[f] && strstr(dmi_ident[f], str))
 964		return 1;
 965	return 0;
 966}
 967
 968/**
 969 *	dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
 970 *	@str: Case sensitive Name
 971 */
 972int dmi_name_in_vendors(const char *str)
 973{
 974	static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 975	int i;
 976	for (i = 0; fields[i] != DMI_NONE; i++) {
 977		int f = fields[i];
 978		if (dmi_ident[f] && strstr(dmi_ident[f], str))
 979			return 1;
 980	}
 981	return 0;
 982}
 983EXPORT_SYMBOL(dmi_name_in_vendors);
 984
 985/**
 986 *	dmi_find_device - find onboard device by type/name
 987 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 988 *	@name: device name string or %NULL to match all
 989 *	@from: previous device found in search, or %NULL for new search.
 990 *
 991 *	Iterates through the list of known onboard devices. If a device is
 992 *	found with a matching @type and @name, a pointer to its device
 993 *	structure is returned.  Otherwise, %NULL is returned.
 994 *	A new search is initiated by passing %NULL as the @from argument.
 995 *	If @from is not %NULL, searches continue from next device.
 996 */
 997const struct dmi_device *dmi_find_device(int type, const char *name,
 998				    const struct dmi_device *from)
 999{
1000	const struct list_head *head = from ? &from->list : &dmi_devices;
1001	struct list_head *d;
1002
1003	for (d = head->next; d != &dmi_devices; d = d->next) {
1004		const struct dmi_device *dev =
1005			list_entry(d, struct dmi_device, list);
1006
1007		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
1008		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
1009			return dev;
1010	}
1011
1012	return NULL;
1013}
1014EXPORT_SYMBOL(dmi_find_device);
1015
1016/**
1017 *	dmi_get_date - parse a DMI date
1018 *	@field:	data index (see enum dmi_field)
1019 *	@yearp: optional out parameter for the year
1020 *	@monthp: optional out parameter for the month
1021 *	@dayp: optional out parameter for the day
1022 *
1023 *	The date field is assumed to be in the form resembling
1024 *	[mm[/dd]]/yy[yy] and the result is stored in the out
1025 *	parameters any or all of which can be omitted.
1026 *
1027 *	If the field doesn't exist, all out parameters are set to zero
1028 *	and false is returned.  Otherwise, true is returned with any
1029 *	invalid part of date set to zero.
1030 *
1031 *	On return, year, month and day are guaranteed to be in the
1032 *	range of [0,9999], [0,12] and [0,31] respectively.
1033 */
1034bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1035{
1036	int year = 0, month = 0, day = 0;
1037	bool exists;
1038	const char *s, *y;
1039	char *e;
1040
1041	s = dmi_get_system_info(field);
1042	exists = s;
1043	if (!exists)
1044		goto out;
1045
1046	/*
1047	 * Determine year first.  We assume the date string resembles
1048	 * mm/dd/yy[yy] but the original code extracted only the year
1049	 * from the end.  Keep the behavior in the spirit of no
1050	 * surprises.
1051	 */
1052	y = strrchr(s, '/');
1053	if (!y)
1054		goto out;
1055
1056	y++;
1057	year = simple_strtoul(y, &e, 10);
1058	if (y != e && year < 100) {	/* 2-digit year */
1059		year += 1900;
1060		if (year < 1996)	/* no dates < spec 1.0 */
1061			year += 100;
1062	}
1063	if (year > 9999)		/* year should fit in %04d */
1064		year = 0;
1065
1066	/* parse the mm and dd */
1067	month = simple_strtoul(s, &e, 10);
1068	if (s == e || *e != '/' || !month || month > 12) {
1069		month = 0;
1070		goto out;
1071	}
1072
1073	s = e + 1;
1074	day = simple_strtoul(s, &e, 10);
1075	if (s == y || s == e || *e != '/' || day > 31)
1076		day = 0;
1077out:
1078	if (yearp)
1079		*yearp = year;
1080	if (monthp)
1081		*monthp = month;
1082	if (dayp)
1083		*dayp = day;
1084	return exists;
1085}
1086EXPORT_SYMBOL(dmi_get_date);
1087
1088/**
1089 *	dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1090 *
1091 *	Returns year on success, -ENXIO if DMI is not selected,
1092 *	or a different negative error code if DMI field is not present
1093 *	or not parseable.
1094 */
1095int dmi_get_bios_year(void)
1096{
1097	bool exists;
1098	int year;
1099
1100	exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1101	if (!exists)
1102		return -ENODATA;
1103
1104	return year ? year : -ERANGE;
1105}
1106EXPORT_SYMBOL(dmi_get_bios_year);
1107
1108/**
1109 *	dmi_walk - Walk the DMI table and get called back for every record
1110 *	@decode: Callback function
1111 *	@private_data: Private data to be passed to the callback function
1112 *
1113 *	Returns 0 on success, -ENXIO if DMI is not selected or not present,
1114 *	or a different negative error code if DMI walking fails.
1115 */
1116int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1117	     void *private_data)
1118{
1119	u8 *buf;
1120
1121	if (!dmi_available)
1122		return -ENXIO;
1123
1124	buf = dmi_remap(dmi_base, dmi_len);
1125	if (buf == NULL)
1126		return -ENOMEM;
1127
1128	dmi_decode_table(buf, decode, private_data);
1129
1130	dmi_unmap(buf);
1131	return 0;
1132}
1133EXPORT_SYMBOL_GPL(dmi_walk);
1134
1135/**
1136 * dmi_match - compare a string to the dmi field (if exists)
1137 * @f: DMI field identifier
1138 * @str: string to compare the DMI field to
1139 *
1140 * Returns true if the requested field equals to the str (including NULL).
1141 */
1142bool dmi_match(enum dmi_field f, const char *str)
1143{
1144	const char *info = dmi_get_system_info(f);
1145
1146	if (info == NULL || str == NULL)
1147		return info == str;
1148
1149	return !strcmp(info, str);
1150}
1151EXPORT_SYMBOL_GPL(dmi_match);
1152
1153void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1154{
1155	int n;
1156
1157	if (dmi_memdev == NULL)
1158		return;
1159
1160	for (n = 0; n < dmi_memdev_nr; n++) {
1161		if (handle == dmi_memdev[n].handle) {
1162			*bank = dmi_memdev[n].bank;
1163			*device = dmi_memdev[n].device;
1164			break;
1165		}
1166	}
1167}
1168EXPORT_SYMBOL_GPL(dmi_memdev_name);
1169
1170u64 dmi_memdev_size(u16 handle)
1171{
1172	int n;
1173
1174	if (dmi_memdev) {
1175		for (n = 0; n < dmi_memdev_nr; n++) {
1176			if (handle == dmi_memdev[n].handle)
1177				return dmi_memdev[n].size;
1178		}
1179	}
1180	return ~0ull;
1181}
1182EXPORT_SYMBOL_GPL(dmi_memdev_size);
1183
1184/**
1185 * dmi_memdev_type - get the memory type
1186 * @handle: DMI structure handle
1187 *
1188 * Return the DMI memory type of the module in the slot associated with the
1189 * given DMI handle, or 0x0 if no such DMI handle exists.
1190 */
1191u8 dmi_memdev_type(u16 handle)
1192{
1193	int n;
1194
1195	if (dmi_memdev) {
1196		for (n = 0; n < dmi_memdev_nr; n++) {
1197			if (handle == dmi_memdev[n].handle)
1198				return dmi_memdev[n].type;
1199		}
1200	}
1201	return 0x0;	/* Not a valid value */
1202}
1203EXPORT_SYMBOL_GPL(dmi_memdev_type);
1204
1205/**
1206 *	dmi_memdev_handle - get the DMI handle of a memory slot
1207 *	@slot: slot number
1208 *
1209 *	Return the DMI handle associated with a given memory slot, or %0xFFFF
1210 *      if there is no such slot.
1211 */
1212u16 dmi_memdev_handle(int slot)
1213{
1214	if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1215		return dmi_memdev[slot].handle;
1216
1217	return 0xffff;	/* Not a valid value */
1218}
1219EXPORT_SYMBOL_GPL(dmi_memdev_handle);
v5.14.15
   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	if (memcmp(buf, "_SM_", 4) == 0 &&
 571	    buf[5] < 32 && dmi_checksum(buf, buf[5])) {
 
 572		smbios_ver = get_unaligned_be16(buf + 6);
 573		smbios_entry_point_size = buf[5];
 574		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 575
 576		/* Some BIOS report weird SMBIOS version, fix that up */
 577		switch (smbios_ver) {
 578		case 0x021F:
 579		case 0x0221:
 580			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
 581				 smbios_ver & 0xFF, 3);
 582			smbios_ver = 0x0203;
 583			break;
 584		case 0x0233:
 585			pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
 586			smbios_ver = 0x0206;
 587			break;
 588		}
 589	} else {
 590		smbios_ver = 0;
 591	}
 592
 593	buf += 16;
 594
 595	if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
 596		if (smbios_ver)
 597			dmi_ver = smbios_ver;
 598		else
 599			dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
 600		dmi_ver <<= 8;
 601		dmi_num = get_unaligned_le16(buf + 12);
 602		dmi_len = get_unaligned_le16(buf + 6);
 603		dmi_base = get_unaligned_le32(buf + 8);
 604
 605		if (dmi_walk_early(dmi_decode) == 0) {
 606			if (smbios_ver) {
 607				pr_info("SMBIOS %d.%d present.\n",
 608					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 609			} else {
 610				smbios_entry_point_size = 15;
 611				memcpy(smbios_entry_point, buf,
 612				       smbios_entry_point_size);
 613				pr_info("Legacy DMI %d.%d present.\n",
 614					dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 615			}
 616			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 617			pr_info("DMI: %s\n", dmi_ids_string);
 618			return 0;
 619		}
 620	}
 621
 622	return 1;
 623}
 624
 625/*
 626 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
 627 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
 628 */
 629static int __init dmi_smbios3_present(const u8 *buf)
 630{
 631	if (memcmp(buf, "_SM3_", 5) == 0 &&
 632	    buf[6] < 32 && dmi_checksum(buf, buf[6])) {
 633		dmi_ver = get_unaligned_be32(buf + 6) & 0xFFFFFF;
 
 634		dmi_num = 0;			/* No longer specified */
 635		dmi_len = get_unaligned_le32(buf + 12);
 636		dmi_base = get_unaligned_le64(buf + 16);
 637		smbios_entry_point_size = buf[6];
 638		memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 639
 640		if (dmi_walk_early(dmi_decode) == 0) {
 641			pr_info("SMBIOS %d.%d.%d present.\n",
 642				dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
 643				dmi_ver & 0xFF);
 644			dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 645			pr_info("DMI: %s\n", dmi_ids_string);
 646			return 0;
 647		}
 648	}
 649	return 1;
 650}
 651
 652static void __init dmi_scan_machine(void)
 653{
 654	char __iomem *p, *q;
 655	char buf[32];
 656
 657	if (efi_enabled(EFI_CONFIG_TABLES)) {
 658		/*
 659		 * According to the DMTF SMBIOS reference spec v3.0.0, it is
 660		 * allowed to define both the 64-bit entry point (smbios3) and
 661		 * the 32-bit entry point (smbios), in which case they should
 662		 * either both point to the same SMBIOS structure table, or the
 663		 * table pointed to by the 64-bit entry point should contain a
 664		 * superset of the table contents pointed to by the 32-bit entry
 665		 * point (section 5.2)
 666		 * This implies that the 64-bit entry point should have
 667		 * precedence if it is defined and supported by the OS. If we
 668		 * have the 64-bit entry point, but fail to decode it, fall
 669		 * back to the legacy one (if available)
 670		 */
 671		if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
 672			p = dmi_early_remap(efi.smbios3, 32);
 673			if (p == NULL)
 674				goto error;
 675			memcpy_fromio(buf, p, 32);
 676			dmi_early_unmap(p, 32);
 677
 678			if (!dmi_smbios3_present(buf)) {
 679				dmi_available = 1;
 680				return;
 681			}
 682		}
 683		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 684			goto error;
 685
 686		/* This is called as a core_initcall() because it isn't
 687		 * needed during early boot.  This also means we can
 688		 * iounmap the space when we're done with it.
 689		 */
 690		p = dmi_early_remap(efi.smbios, 32);
 691		if (p == NULL)
 692			goto error;
 693		memcpy_fromio(buf, p, 32);
 694		dmi_early_unmap(p, 32);
 695
 696		if (!dmi_present(buf)) {
 697			dmi_available = 1;
 698			return;
 699		}
 700	} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
 701		p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
 702		if (p == NULL)
 703			goto error;
 704
 705		/*
 706		 * Same logic as above, look for a 64-bit entry point
 707		 * first, and if not found, fall back to 32-bit entry point.
 708		 */
 709		memcpy_fromio(buf, p, 16);
 710		for (q = p + 16; q < p + 0x10000; q += 16) {
 711			memcpy_fromio(buf + 16, q, 16);
 712			if (!dmi_smbios3_present(buf)) {
 713				dmi_available = 1;
 714				dmi_early_unmap(p, 0x10000);
 715				return;
 716			}
 717			memcpy(buf, buf + 16, 16);
 718		}
 719
 720		/*
 721		 * Iterate over all possible DMI header addresses q.
 722		 * Maintain the 32 bytes around q in buf.  On the
 723		 * first iteration, substitute zero for the
 724		 * out-of-range bytes so there is no chance of falsely
 725		 * detecting an SMBIOS header.
 726		 */
 727		memset(buf, 0, 16);
 728		for (q = p; q < p + 0x10000; q += 16) {
 729			memcpy_fromio(buf + 16, q, 16);
 730			if (!dmi_present(buf)) {
 731				dmi_available = 1;
 732				dmi_early_unmap(p, 0x10000);
 733				return;
 734			}
 735			memcpy(buf, buf + 16, 16);
 736		}
 737		dmi_early_unmap(p, 0x10000);
 738	}
 739 error:
 740	pr_info("DMI not present or invalid.\n");
 741}
 742
 743static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
 744			      struct bin_attribute *attr, char *buf,
 745			      loff_t pos, size_t count)
 746{
 747	memcpy(buf, attr->private + pos, count);
 748	return count;
 749}
 750
 751static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
 752static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
 753
 754static int __init dmi_init(void)
 755{
 756	struct kobject *tables_kobj;
 757	u8 *dmi_table;
 758	int ret = -ENOMEM;
 759
 760	if (!dmi_available)
 761		return 0;
 762
 763	/*
 764	 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
 765	 * even after farther error, as it can be used by other modules like
 766	 * dmi-sysfs.
 767	 */
 768	dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
 769	if (!dmi_kobj)
 770		goto err;
 771
 772	tables_kobj = kobject_create_and_add("tables", dmi_kobj);
 773	if (!tables_kobj)
 774		goto err;
 775
 776	dmi_table = dmi_remap(dmi_base, dmi_len);
 777	if (!dmi_table)
 778		goto err_tables;
 779
 780	bin_attr_smbios_entry_point.size = smbios_entry_point_size;
 781	bin_attr_smbios_entry_point.private = smbios_entry_point;
 782	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
 783	if (ret)
 784		goto err_unmap;
 785
 786	bin_attr_DMI.size = dmi_len;
 787	bin_attr_DMI.private = dmi_table;
 788	ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
 789	if (!ret)
 790		return 0;
 791
 792	sysfs_remove_bin_file(tables_kobj,
 793			      &bin_attr_smbios_entry_point);
 794 err_unmap:
 795	dmi_unmap(dmi_table);
 796 err_tables:
 797	kobject_del(tables_kobj);
 798	kobject_put(tables_kobj);
 799 err:
 800	pr_err("dmi: Firmware registration failed.\n");
 801
 802	return ret;
 803}
 804subsys_initcall(dmi_init);
 805
 806/**
 807 *	dmi_setup - scan and setup DMI system information
 808 *
 809 *	Scan the DMI system information. This setups DMI identifiers
 810 *	(dmi_system_id) for printing it out on task dumps and prepares
 811 *	DIMM entry information (dmi_memdev_info) from the SMBIOS table
 812 *	for using this when reporting memory errors.
 813 */
 814void __init dmi_setup(void)
 815{
 816	dmi_scan_machine();
 817	if (!dmi_available)
 818		return;
 819
 820	dmi_memdev_walk();
 
 
 821	dump_stack_set_arch_desc("%s", dmi_ids_string);
 822}
 823
 824/**
 825 *	dmi_matches - check if dmi_system_id structure matches system DMI data
 826 *	@dmi: pointer to the dmi_system_id structure to check
 827 */
 828static bool dmi_matches(const struct dmi_system_id *dmi)
 829{
 830	int i;
 831
 832	for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
 833		int s = dmi->matches[i].slot;
 834		if (s == DMI_NONE)
 835			break;
 836		if (s == DMI_OEM_STRING) {
 837			/* DMI_OEM_STRING must be exact match */
 838			const struct dmi_device *valid;
 839
 840			valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
 841						dmi->matches[i].substr, NULL);
 842			if (valid)
 843				continue;
 844		} else if (dmi_ident[s]) {
 845			if (dmi->matches[i].exact_match) {
 846				if (!strcmp(dmi_ident[s],
 847					    dmi->matches[i].substr))
 848					continue;
 849			} else {
 850				if (strstr(dmi_ident[s],
 851					   dmi->matches[i].substr))
 852					continue;
 853			}
 854		}
 855
 856		/* No match */
 857		return false;
 858	}
 859	return true;
 860}
 861
 862/**
 863 *	dmi_is_end_of_table - check for end-of-table marker
 864 *	@dmi: pointer to the dmi_system_id structure to check
 865 */
 866static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
 867{
 868	return dmi->matches[0].slot == DMI_NONE;
 869}
 870
 871/**
 872 *	dmi_check_system - check system DMI data
 873 *	@list: array of dmi_system_id structures to match against
 874 *		All non-null elements of the list must match
 875 *		their slot's (field index's) data (i.e., each
 876 *		list string must be a substring of the specified
 877 *		DMI slot's string data) to be considered a
 878 *		successful match.
 879 *
 880 *	Walk the blacklist table running matching functions until someone
 881 *	returns non zero or we hit the end. Callback function is called for
 882 *	each successful match. Returns the number of matches.
 883 *
 884 *	dmi_setup must be called before this function is called.
 885 */
 886int dmi_check_system(const struct dmi_system_id *list)
 887{
 888	int count = 0;
 889	const struct dmi_system_id *d;
 890
 891	for (d = list; !dmi_is_end_of_table(d); d++)
 892		if (dmi_matches(d)) {
 893			count++;
 894			if (d->callback && d->callback(d))
 895				break;
 896		}
 897
 898	return count;
 899}
 900EXPORT_SYMBOL(dmi_check_system);
 901
 902/**
 903 *	dmi_first_match - find dmi_system_id structure matching system DMI data
 904 *	@list: array of dmi_system_id structures to match against
 905 *		All non-null elements of the list must match
 906 *		their slot's (field index's) data (i.e., each
 907 *		list string must be a substring of the specified
 908 *		DMI slot's string data) to be considered a
 909 *		successful match.
 910 *
 911 *	Walk the blacklist table until the first match is found.  Return the
 912 *	pointer to the matching entry or NULL if there's no match.
 913 *
 914 *	dmi_setup must be called before this function is called.
 915 */
 916const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 917{
 918	const struct dmi_system_id *d;
 919
 920	for (d = list; !dmi_is_end_of_table(d); d++)
 921		if (dmi_matches(d))
 922			return d;
 923
 924	return NULL;
 925}
 926EXPORT_SYMBOL(dmi_first_match);
 927
 928/**
 929 *	dmi_get_system_info - return DMI data value
 930 *	@field: data index (see enum dmi_field)
 931 *
 932 *	Returns one DMI data value, can be used to perform
 933 *	complex DMI data checks.
 934 */
 935const char *dmi_get_system_info(int field)
 936{
 937	return dmi_ident[field];
 938}
 939EXPORT_SYMBOL(dmi_get_system_info);
 940
 941/**
 942 * dmi_name_in_serial - Check if string is in the DMI product serial information
 943 * @str: string to check for
 944 */
 945int dmi_name_in_serial(const char *str)
 946{
 947	int f = DMI_PRODUCT_SERIAL;
 948	if (dmi_ident[f] && strstr(dmi_ident[f], str))
 949		return 1;
 950	return 0;
 951}
 952
 953/**
 954 *	dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
 955 *	@str: Case sensitive Name
 956 */
 957int dmi_name_in_vendors(const char *str)
 958{
 959	static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 960	int i;
 961	for (i = 0; fields[i] != DMI_NONE; i++) {
 962		int f = fields[i];
 963		if (dmi_ident[f] && strstr(dmi_ident[f], str))
 964			return 1;
 965	}
 966	return 0;
 967}
 968EXPORT_SYMBOL(dmi_name_in_vendors);
 969
 970/**
 971 *	dmi_find_device - find onboard device by type/name
 972 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 973 *	@name: device name string or %NULL to match all
 974 *	@from: previous device found in search, or %NULL for new search.
 975 *
 976 *	Iterates through the list of known onboard devices. If a device is
 977 *	found with a matching @type and @name, a pointer to its device
 978 *	structure is returned.  Otherwise, %NULL is returned.
 979 *	A new search is initiated by passing %NULL as the @from argument.
 980 *	If @from is not %NULL, searches continue from next device.
 981 */
 982const struct dmi_device *dmi_find_device(int type, const char *name,
 983				    const struct dmi_device *from)
 984{
 985	const struct list_head *head = from ? &from->list : &dmi_devices;
 986	struct list_head *d;
 987
 988	for (d = head->next; d != &dmi_devices; d = d->next) {
 989		const struct dmi_device *dev =
 990			list_entry(d, struct dmi_device, list);
 991
 992		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
 993		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
 994			return dev;
 995	}
 996
 997	return NULL;
 998}
 999EXPORT_SYMBOL(dmi_find_device);
1000
1001/**
1002 *	dmi_get_date - parse a DMI date
1003 *	@field:	data index (see enum dmi_field)
1004 *	@yearp: optional out parameter for the year
1005 *	@monthp: optional out parameter for the month
1006 *	@dayp: optional out parameter for the day
1007 *
1008 *	The date field is assumed to be in the form resembling
1009 *	[mm[/dd]]/yy[yy] and the result is stored in the out
1010 *	parameters any or all of which can be omitted.
1011 *
1012 *	If the field doesn't exist, all out parameters are set to zero
1013 *	and false is returned.  Otherwise, true is returned with any
1014 *	invalid part of date set to zero.
1015 *
1016 *	On return, year, month and day are guaranteed to be in the
1017 *	range of [0,9999], [0,12] and [0,31] respectively.
1018 */
1019bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1020{
1021	int year = 0, month = 0, day = 0;
1022	bool exists;
1023	const char *s, *y;
1024	char *e;
1025
1026	s = dmi_get_system_info(field);
1027	exists = s;
1028	if (!exists)
1029		goto out;
1030
1031	/*
1032	 * Determine year first.  We assume the date string resembles
1033	 * mm/dd/yy[yy] but the original code extracted only the year
1034	 * from the end.  Keep the behavior in the spirit of no
1035	 * surprises.
1036	 */
1037	y = strrchr(s, '/');
1038	if (!y)
1039		goto out;
1040
1041	y++;
1042	year = simple_strtoul(y, &e, 10);
1043	if (y != e && year < 100) {	/* 2-digit year */
1044		year += 1900;
1045		if (year < 1996)	/* no dates < spec 1.0 */
1046			year += 100;
1047	}
1048	if (year > 9999)		/* year should fit in %04d */
1049		year = 0;
1050
1051	/* parse the mm and dd */
1052	month = simple_strtoul(s, &e, 10);
1053	if (s == e || *e != '/' || !month || month > 12) {
1054		month = 0;
1055		goto out;
1056	}
1057
1058	s = e + 1;
1059	day = simple_strtoul(s, &e, 10);
1060	if (s == y || s == e || *e != '/' || day > 31)
1061		day = 0;
1062out:
1063	if (yearp)
1064		*yearp = year;
1065	if (monthp)
1066		*monthp = month;
1067	if (dayp)
1068		*dayp = day;
1069	return exists;
1070}
1071EXPORT_SYMBOL(dmi_get_date);
1072
1073/**
1074 *	dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1075 *
1076 *	Returns year on success, -ENXIO if DMI is not selected,
1077 *	or a different negative error code if DMI field is not present
1078 *	or not parseable.
1079 */
1080int dmi_get_bios_year(void)
1081{
1082	bool exists;
1083	int year;
1084
1085	exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1086	if (!exists)
1087		return -ENODATA;
1088
1089	return year ? year : -ERANGE;
1090}
1091EXPORT_SYMBOL(dmi_get_bios_year);
1092
1093/**
1094 *	dmi_walk - Walk the DMI table and get called back for every record
1095 *	@decode: Callback function
1096 *	@private_data: Private data to be passed to the callback function
1097 *
1098 *	Returns 0 on success, -ENXIO if DMI is not selected or not present,
1099 *	or a different negative error code if DMI walking fails.
1100 */
1101int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1102	     void *private_data)
1103{
1104	u8 *buf;
1105
1106	if (!dmi_available)
1107		return -ENXIO;
1108
1109	buf = dmi_remap(dmi_base, dmi_len);
1110	if (buf == NULL)
1111		return -ENOMEM;
1112
1113	dmi_decode_table(buf, decode, private_data);
1114
1115	dmi_unmap(buf);
1116	return 0;
1117}
1118EXPORT_SYMBOL_GPL(dmi_walk);
1119
1120/**
1121 * dmi_match - compare a string to the dmi field (if exists)
1122 * @f: DMI field identifier
1123 * @str: string to compare the DMI field to
1124 *
1125 * Returns true if the requested field equals to the str (including NULL).
1126 */
1127bool dmi_match(enum dmi_field f, const char *str)
1128{
1129	const char *info = dmi_get_system_info(f);
1130
1131	if (info == NULL || str == NULL)
1132		return info == str;
1133
1134	return !strcmp(info, str);
1135}
1136EXPORT_SYMBOL_GPL(dmi_match);
1137
1138void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1139{
1140	int n;
1141
1142	if (dmi_memdev == NULL)
1143		return;
1144
1145	for (n = 0; n < dmi_memdev_nr; n++) {
1146		if (handle == dmi_memdev[n].handle) {
1147			*bank = dmi_memdev[n].bank;
1148			*device = dmi_memdev[n].device;
1149			break;
1150		}
1151	}
1152}
1153EXPORT_SYMBOL_GPL(dmi_memdev_name);
1154
1155u64 dmi_memdev_size(u16 handle)
1156{
1157	int n;
1158
1159	if (dmi_memdev) {
1160		for (n = 0; n < dmi_memdev_nr; n++) {
1161			if (handle == dmi_memdev[n].handle)
1162				return dmi_memdev[n].size;
1163		}
1164	}
1165	return ~0ull;
1166}
1167EXPORT_SYMBOL_GPL(dmi_memdev_size);
1168
1169/**
1170 * dmi_memdev_type - get the memory type
1171 * @handle: DMI structure handle
1172 *
1173 * Return the DMI memory type of the module in the slot associated with the
1174 * given DMI handle, or 0x0 if no such DMI handle exists.
1175 */
1176u8 dmi_memdev_type(u16 handle)
1177{
1178	int n;
1179
1180	if (dmi_memdev) {
1181		for (n = 0; n < dmi_memdev_nr; n++) {
1182			if (handle == dmi_memdev[n].handle)
1183				return dmi_memdev[n].type;
1184		}
1185	}
1186	return 0x0;	/* Not a valid value */
1187}
1188EXPORT_SYMBOL_GPL(dmi_memdev_type);
1189
1190/**
1191 *	dmi_memdev_handle - get the DMI handle of a memory slot
1192 *	@slot: slot number
1193 *
1194 *	Return the DMI handle associated with a given memory slot, or %0xFFFF
1195 *      if there is no such slot.
1196 */
1197u16 dmi_memdev_handle(int slot)
1198{
1199	if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1200		return dmi_memdev[slot].handle;
1201
1202	return 0xffff;	/* Not a valid value */
1203}
1204EXPORT_SYMBOL_GPL(dmi_memdev_handle);