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v3.5.6
   1/*
   2 * Handle the memory map.
   3 * The functions here do the job until bootmem takes over.
   4 *
   5 *  Getting sanitize_e820_map() in sync with i386 version by applying change:
   6 *  -  Provisions for empty E820 memory regions (reported by certain BIOSes).
   7 *     Alex Achenbach <xela@slit.de>, December 2002.
   8 *  Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
   9 *
  10 */
  11#include <linux/kernel.h>
  12#include <linux/types.h>
  13#include <linux/init.h>
  14#include <linux/crash_dump.h>
  15#include <linux/export.h>
  16#include <linux/bootmem.h>
  17#include <linux/pfn.h>
  18#include <linux/suspend.h>
  19#include <linux/acpi.h>
  20#include <linux/firmware-map.h>
  21#include <linux/memblock.h>
  22#include <linux/sort.h>
  23
  24#include <asm/e820.h>
  25#include <asm/proto.h>
  26#include <asm/setup.h>
  27
  28/*
  29 * The e820 map is the map that gets modified e.g. with command line parameters
  30 * and that is also registered with modifications in the kernel resource tree
  31 * with the iomem_resource as parent.
  32 *
  33 * The e820_saved is directly saved after the BIOS-provided memory map is
  34 * copied. It doesn't get modified afterwards. It's registered for the
  35 * /sys/firmware/memmap interface.
  36 *
  37 * That memory map is not modified and is used as base for kexec. The kexec'd
  38 * kernel should get the same memory map as the firmware provides. Then the
  39 * user can e.g. boot the original kernel with mem=1G while still booting the
  40 * next kernel with full memory.
  41 */
  42struct e820map e820;
  43struct e820map e820_saved;
  44
  45/* For PCI or other memory-mapped resources */
  46unsigned long pci_mem_start = 0xaeedbabe;
  47#ifdef CONFIG_PCI
  48EXPORT_SYMBOL(pci_mem_start);
  49#endif
  50
  51/*
  52 * This function checks if any part of the range <start,end> is mapped
  53 * with type.
  54 */
  55int
  56e820_any_mapped(u64 start, u64 end, unsigned type)
  57{
  58	int i;
  59
  60	for (i = 0; i < e820.nr_map; i++) {
  61		struct e820entry *ei = &e820.map[i];
  62
  63		if (type && ei->type != type)
  64			continue;
  65		if (ei->addr >= end || ei->addr + ei->size <= start)
  66			continue;
  67		return 1;
  68	}
  69	return 0;
  70}
  71EXPORT_SYMBOL_GPL(e820_any_mapped);
  72
  73/*
  74 * This function checks if the entire range <start,end> is mapped with type.
  75 *
  76 * Note: this function only works correct if the e820 table is sorted and
  77 * not-overlapping, which is the case
  78 */
  79int __init e820_all_mapped(u64 start, u64 end, unsigned type)
  80{
  81	int i;
  82
  83	for (i = 0; i < e820.nr_map; i++) {
  84		struct e820entry *ei = &e820.map[i];
  85
  86		if (type && ei->type != type)
  87			continue;
  88		/* is the region (part) in overlap with the current region ?*/
  89		if (ei->addr >= end || ei->addr + ei->size <= start)
  90			continue;
  91
  92		/* if the region is at the beginning of <start,end> we move
  93		 * start to the end of the region since it's ok until there
  94		 */
  95		if (ei->addr <= start)
  96			start = ei->addr + ei->size;
  97		/*
  98		 * if start is now at or beyond end, we're done, full
  99		 * coverage
 100		 */
 101		if (start >= end)
 102			return 1;
 103	}
 104	return 0;
 105}
 106
 107/*
 108 * Add a memory region to the kernel e820 map.
 109 */
 110static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
 111					 int type)
 112{
 113	int x = e820x->nr_map;
 114
 115	if (x >= ARRAY_SIZE(e820x->map)) {
 116		printk(KERN_ERR "e820: too many entries; ignoring [mem %#010llx-%#010llx]\n",
 117		       (unsigned long long) start,
 118		       (unsigned long long) (start + size - 1));
 119		return;
 120	}
 121
 122	e820x->map[x].addr = start;
 123	e820x->map[x].size = size;
 124	e820x->map[x].type = type;
 125	e820x->nr_map++;
 126}
 127
 128void __init e820_add_region(u64 start, u64 size, int type)
 129{
 130	__e820_add_region(&e820, start, size, type);
 131}
 132
 133static void __init e820_print_type(u32 type)
 134{
 135	switch (type) {
 136	case E820_RAM:
 137	case E820_RESERVED_KERN:
 138		printk(KERN_CONT "usable");
 139		break;
 140	case E820_RESERVED:
 141		printk(KERN_CONT "reserved");
 142		break;
 143	case E820_ACPI:
 144		printk(KERN_CONT "ACPI data");
 145		break;
 146	case E820_NVS:
 147		printk(KERN_CONT "ACPI NVS");
 148		break;
 149	case E820_UNUSABLE:
 150		printk(KERN_CONT "unusable");
 151		break;
 152	default:
 153		printk(KERN_CONT "type %u", type);
 154		break;
 155	}
 156}
 157
 158void __init e820_print_map(char *who)
 159{
 160	int i;
 161
 162	for (i = 0; i < e820.nr_map; i++) {
 163		printk(KERN_INFO "%s: [mem %#018Lx-%#018Lx] ", who,
 164		       (unsigned long long) e820.map[i].addr,
 165		       (unsigned long long)
 166		       (e820.map[i].addr + e820.map[i].size - 1));
 167		e820_print_type(e820.map[i].type);
 168		printk(KERN_CONT "\n");
 169	}
 170}
 171
 172/*
 173 * Sanitize the BIOS e820 map.
 174 *
 175 * Some e820 responses include overlapping entries. The following
 176 * replaces the original e820 map with a new one, removing overlaps,
 177 * and resolving conflicting memory types in favor of highest
 178 * numbered type.
 179 *
 180 * The input parameter biosmap points to an array of 'struct
 181 * e820entry' which on entry has elements in the range [0, *pnr_map)
 182 * valid, and which has space for up to max_nr_map entries.
 183 * On return, the resulting sanitized e820 map entries will be in
 184 * overwritten in the same location, starting at biosmap.
 185 *
 186 * The integer pointed to by pnr_map must be valid on entry (the
 187 * current number of valid entries located at biosmap) and will
 188 * be updated on return, with the new number of valid entries
 189 * (something no more than max_nr_map.)
 190 *
 191 * The return value from sanitize_e820_map() is zero if it
 192 * successfully 'sanitized' the map entries passed in, and is -1
 193 * if it did nothing, which can happen if either of (1) it was
 194 * only passed one map entry, or (2) any of the input map entries
 195 * were invalid (start + size < start, meaning that the size was
 196 * so big the described memory range wrapped around through zero.)
 197 *
 198 *	Visually we're performing the following
 199 *	(1,2,3,4 = memory types)...
 200 *
 201 *	Sample memory map (w/overlaps):
 202 *	   ____22__________________
 203 *	   ______________________4_
 204 *	   ____1111________________
 205 *	   _44_____________________
 206 *	   11111111________________
 207 *	   ____________________33__
 208 *	   ___________44___________
 209 *	   __________33333_________
 210 *	   ______________22________
 211 *	   ___________________2222_
 212 *	   _________111111111______
 213 *	   _____________________11_
 214 *	   _________________4______
 215 *
 216 *	Sanitized equivalent (no overlap):
 217 *	   1_______________________
 218 *	   _44_____________________
 219 *	   ___1____________________
 220 *	   ____22__________________
 221 *	   ______11________________
 222 *	   _________1______________
 223 *	   __________3_____________
 224 *	   ___________44___________
 225 *	   _____________33_________
 226 *	   _______________2________
 227 *	   ________________1_______
 228 *	   _________________4______
 229 *	   ___________________2____
 230 *	   ____________________33__
 231 *	   ______________________4_
 232 */
 233struct change_member {
 234	struct e820entry *pbios; /* pointer to original bios entry */
 235	unsigned long long addr; /* address for this change point */
 236};
 237
 238static int __init cpcompare(const void *a, const void *b)
 239{
 240	struct change_member * const *app = a, * const *bpp = b;
 241	const struct change_member *ap = *app, *bp = *bpp;
 242
 243	/*
 244	 * Inputs are pointers to two elements of change_point[].  If their
 245	 * addresses are unequal, their difference dominates.  If the addresses
 246	 * are equal, then consider one that represents the end of its region
 247	 * to be greater than one that does not.
 248	 */
 249	if (ap->addr != bp->addr)
 250		return ap->addr > bp->addr ? 1 : -1;
 251
 252	return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr);
 253}
 254
 255int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
 256			     u32 *pnr_map)
 257{
 
 
 
 
 258	static struct change_member change_point_list[2*E820_X_MAX] __initdata;
 259	static struct change_member *change_point[2*E820_X_MAX] __initdata;
 260	static struct e820entry *overlap_list[E820_X_MAX] __initdata;
 261	static struct e820entry new_bios[E820_X_MAX] __initdata;
 
 262	unsigned long current_type, last_type;
 263	unsigned long long last_addr;
 264	int chgidx;
 265	int overlap_entries;
 266	int new_bios_entry;
 267	int old_nr, new_nr, chg_nr;
 268	int i;
 269
 270	/* if there's only one memory region, don't bother */
 271	if (*pnr_map < 2)
 272		return -1;
 273
 274	old_nr = *pnr_map;
 275	BUG_ON(old_nr > max_nr_map);
 276
 277	/* bail out if we find any unreasonable addresses in bios map */
 278	for (i = 0; i < old_nr; i++)
 279		if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
 280			return -1;
 281
 282	/* create pointers for initial change-point information (for sorting) */
 283	for (i = 0; i < 2 * old_nr; i++)
 284		change_point[i] = &change_point_list[i];
 285
 286	/* record all known change-points (starting and ending addresses),
 287	   omitting those that are for empty memory regions */
 288	chgidx = 0;
 289	for (i = 0; i < old_nr; i++)	{
 290		if (biosmap[i].size != 0) {
 291			change_point[chgidx]->addr = biosmap[i].addr;
 292			change_point[chgidx++]->pbios = &biosmap[i];
 293			change_point[chgidx]->addr = biosmap[i].addr +
 294				biosmap[i].size;
 295			change_point[chgidx++]->pbios = &biosmap[i];
 296		}
 297	}
 298	chg_nr = chgidx;
 299
 300	/* sort change-point list by memory addresses (low -> high) */
 301	sort(change_point, chg_nr, sizeof *change_point, cpcompare, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 302
 303	/* create a new bios memory map, removing overlaps */
 304	overlap_entries = 0;	 /* number of entries in the overlap table */
 305	new_bios_entry = 0;	 /* index for creating new bios map entries */
 306	last_type = 0;		 /* start with undefined memory type */
 307	last_addr = 0;		 /* start with 0 as last starting address */
 308
 309	/* loop through change-points, determining affect on the new bios map */
 310	for (chgidx = 0; chgidx < chg_nr; chgidx++) {
 311		/* keep track of all overlapping bios entries */
 312		if (change_point[chgidx]->addr ==
 313		    change_point[chgidx]->pbios->addr) {
 314			/*
 315			 * add map entry to overlap list (> 1 entry
 316			 * implies an overlap)
 317			 */
 318			overlap_list[overlap_entries++] =
 319				change_point[chgidx]->pbios;
 320		} else {
 321			/*
 322			 * remove entry from list (order independent,
 323			 * so swap with last)
 324			 */
 325			for (i = 0; i < overlap_entries; i++) {
 326				if (overlap_list[i] ==
 327				    change_point[chgidx]->pbios)
 328					overlap_list[i] =
 329						overlap_list[overlap_entries-1];
 330			}
 331			overlap_entries--;
 332		}
 333		/*
 334		 * if there are overlapping entries, decide which
 335		 * "type" to use (larger value takes precedence --
 336		 * 1=usable, 2,3,4,4+=unusable)
 337		 */
 338		current_type = 0;
 339		for (i = 0; i < overlap_entries; i++)
 340			if (overlap_list[i]->type > current_type)
 341				current_type = overlap_list[i]->type;
 342		/*
 343		 * continue building up new bios map based on this
 344		 * information
 345		 */
 346		if (current_type != last_type)	{
 347			if (last_type != 0)	 {
 348				new_bios[new_bios_entry].size =
 349					change_point[chgidx]->addr - last_addr;
 350				/*
 351				 * move forward only if the new size
 352				 * was non-zero
 353				 */
 354				if (new_bios[new_bios_entry].size != 0)
 355					/*
 356					 * no more space left for new
 357					 * bios entries ?
 358					 */
 359					if (++new_bios_entry >= max_nr_map)
 360						break;
 361			}
 362			if (current_type != 0)	{
 363				new_bios[new_bios_entry].addr =
 364					change_point[chgidx]->addr;
 365				new_bios[new_bios_entry].type = current_type;
 366				last_addr = change_point[chgidx]->addr;
 367			}
 368			last_type = current_type;
 369		}
 370	}
 371	/* retain count for new bios entries */
 372	new_nr = new_bios_entry;
 373
 374	/* copy new bios mapping into original location */
 375	memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
 376	*pnr_map = new_nr;
 377
 378	return 0;
 379}
 380
 381static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
 382{
 383	while (nr_map) {
 384		u64 start = biosmap->addr;
 385		u64 size = biosmap->size;
 386		u64 end = start + size;
 387		u32 type = biosmap->type;
 388
 389		/* Overflow in 64 bits? Ignore the memory map. */
 390		if (start > end)
 391			return -1;
 392
 393		e820_add_region(start, size, type);
 394
 395		biosmap++;
 396		nr_map--;
 397	}
 398	return 0;
 399}
 400
 401/*
 402 * Copy the BIOS e820 map into a safe place.
 403 *
 404 * Sanity-check it while we're at it..
 405 *
 406 * If we're lucky and live on a modern system, the setup code
 407 * will have given us a memory map that we can use to properly
 408 * set up memory.  If we aren't, we'll fake a memory map.
 409 */
 410static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
 411{
 412	/* Only one memory region (or negative)? Ignore it */
 413	if (nr_map < 2)
 414		return -1;
 415
 416	return __append_e820_map(biosmap, nr_map);
 417}
 418
 419static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
 420					u64 size, unsigned old_type,
 421					unsigned new_type)
 422{
 423	u64 end;
 424	unsigned int i;
 425	u64 real_updated_size = 0;
 426
 427	BUG_ON(old_type == new_type);
 428
 429	if (size > (ULLONG_MAX - start))
 430		size = ULLONG_MAX - start;
 431
 432	end = start + size;
 433	printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ",
 434	       (unsigned long long) start, (unsigned long long) (end - 1));
 
 435	e820_print_type(old_type);
 436	printk(KERN_CONT " ==> ");
 437	e820_print_type(new_type);
 438	printk(KERN_CONT "\n");
 439
 440	for (i = 0; i < e820x->nr_map; i++) {
 441		struct e820entry *ei = &e820x->map[i];
 442		u64 final_start, final_end;
 443		u64 ei_end;
 444
 445		if (ei->type != old_type)
 446			continue;
 447
 448		ei_end = ei->addr + ei->size;
 449		/* totally covered by new range? */
 450		if (ei->addr >= start && ei_end <= end) {
 451			ei->type = new_type;
 452			real_updated_size += ei->size;
 453			continue;
 454		}
 455
 456		/* new range is totally covered? */
 457		if (ei->addr < start && ei_end > end) {
 458			__e820_add_region(e820x, start, size, new_type);
 459			__e820_add_region(e820x, end, ei_end - end, ei->type);
 460			ei->size = start - ei->addr;
 461			real_updated_size += size;
 462			continue;
 463		}
 464
 465		/* partially covered */
 466		final_start = max(start, ei->addr);
 467		final_end = min(end, ei_end);
 468		if (final_start >= final_end)
 469			continue;
 470
 471		__e820_add_region(e820x, final_start, final_end - final_start,
 472				  new_type);
 473
 474		real_updated_size += final_end - final_start;
 475
 476		/*
 477		 * left range could be head or tail, so need to update
 478		 * size at first.
 479		 */
 480		ei->size -= final_end - final_start;
 481		if (ei->addr < final_start)
 482			continue;
 483		ei->addr = final_end;
 484	}
 485	return real_updated_size;
 486}
 487
 488u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
 489			     unsigned new_type)
 490{
 491	return __e820_update_range(&e820, start, size, old_type, new_type);
 492}
 493
 494static u64 __init e820_update_range_saved(u64 start, u64 size,
 495					  unsigned old_type, unsigned new_type)
 496{
 497	return __e820_update_range(&e820_saved, start, size, old_type,
 498				     new_type);
 499}
 500
 501/* make e820 not cover the range */
 502u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
 503			     int checktype)
 504{
 505	int i;
 506	u64 end;
 507	u64 real_removed_size = 0;
 508
 509	if (size > (ULLONG_MAX - start))
 510		size = ULLONG_MAX - start;
 511
 512	end = start + size;
 513	printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ",
 514	       (unsigned long long) start, (unsigned long long) (end - 1));
 
 515	if (checktype)
 516		e820_print_type(old_type);
 517	printk(KERN_CONT "\n");
 518
 519	for (i = 0; i < e820.nr_map; i++) {
 520		struct e820entry *ei = &e820.map[i];
 521		u64 final_start, final_end;
 522		u64 ei_end;
 523
 524		if (checktype && ei->type != old_type)
 525			continue;
 526
 527		ei_end = ei->addr + ei->size;
 528		/* totally covered? */
 529		if (ei->addr >= start && ei_end <= end) {
 530			real_removed_size += ei->size;
 531			memset(ei, 0, sizeof(struct e820entry));
 532			continue;
 533		}
 534
 535		/* new range is totally covered? */
 536		if (ei->addr < start && ei_end > end) {
 537			e820_add_region(end, ei_end - end, ei->type);
 538			ei->size = start - ei->addr;
 539			real_removed_size += size;
 540			continue;
 541		}
 542
 543		/* partially covered */
 544		final_start = max(start, ei->addr);
 545		final_end = min(end, ei_end);
 546		if (final_start >= final_end)
 547			continue;
 548		real_removed_size += final_end - final_start;
 549
 550		/*
 551		 * left range could be head or tail, so need to update
 552		 * size at first.
 553		 */
 554		ei->size -= final_end - final_start;
 555		if (ei->addr < final_start)
 556			continue;
 557		ei->addr = final_end;
 558	}
 559	return real_removed_size;
 560}
 561
 562void __init update_e820(void)
 563{
 564	u32 nr_map;
 565
 566	nr_map = e820.nr_map;
 567	if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
 568		return;
 569	e820.nr_map = nr_map;
 570	printk(KERN_INFO "e820: modified physical RAM map:\n");
 571	e820_print_map("modified");
 572}
 573static void __init update_e820_saved(void)
 574{
 575	u32 nr_map;
 576
 577	nr_map = e820_saved.nr_map;
 578	if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
 579		return;
 580	e820_saved.nr_map = nr_map;
 581}
 582#define MAX_GAP_END 0x100000000ull
 583/*
 584 * Search for a gap in the e820 memory space from start_addr to end_addr.
 585 */
 586__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
 587		unsigned long start_addr, unsigned long long end_addr)
 588{
 589	unsigned long long last;
 590	int i = e820.nr_map;
 591	int found = 0;
 592
 593	last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
 594
 595	while (--i >= 0) {
 596		unsigned long long start = e820.map[i].addr;
 597		unsigned long long end = start + e820.map[i].size;
 598
 599		if (end < start_addr)
 600			continue;
 601
 602		/*
 603		 * Since "last" is at most 4GB, we know we'll
 604		 * fit in 32 bits if this condition is true
 605		 */
 606		if (last > end) {
 607			unsigned long gap = last - end;
 608
 609			if (gap >= *gapsize) {
 610				*gapsize = gap;
 611				*gapstart = end;
 612				found = 1;
 613			}
 614		}
 615		if (start < last)
 616			last = start;
 617	}
 618	return found;
 619}
 620
 621/*
 622 * Search for the biggest gap in the low 32 bits of the e820
 623 * memory space.  We pass this space to PCI to assign MMIO resources
 624 * for hotplug or unconfigured devices in.
 625 * Hopefully the BIOS let enough space left.
 626 */
 627__init void e820_setup_gap(void)
 628{
 629	unsigned long gapstart, gapsize;
 630	int found;
 631
 632	gapstart = 0x10000000;
 633	gapsize = 0x400000;
 634	found  = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
 635
 636#ifdef CONFIG_X86_64
 637	if (!found) {
 638		gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
 639		printk(KERN_ERR
 640	"e820: cannot find a gap in the 32bit address range\n"
 641	"e820: PCI devices with unassigned 32bit BARs may break!\n");
 642	}
 643#endif
 644
 645	/*
 646	 * e820_reserve_resources_late protect stolen RAM already
 647	 */
 648	pci_mem_start = gapstart;
 649
 650	printk(KERN_INFO
 651	       "e820: [mem %#010lx-%#010lx] available for PCI devices\n",
 652	       gapstart, gapstart + gapsize - 1);
 653}
 654
 655/**
 656 * Because of the size limitation of struct boot_params, only first
 657 * 128 E820 memory entries are passed to kernel via
 658 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
 659 * linked list of struct setup_data, which is parsed here.
 660 */
 661void __init parse_e820_ext(struct setup_data *sdata)
 662{
 663	int entries;
 664	struct e820entry *extmap;
 665
 666	entries = sdata->len / sizeof(struct e820entry);
 667	extmap = (struct e820entry *)(sdata->data);
 668	__append_e820_map(extmap, entries);
 669	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 670	printk(KERN_INFO "e820: extended physical RAM map:\n");
 671	e820_print_map("extended");
 672}
 673
 674#if defined(CONFIG_X86_64) || \
 675	(defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
 676/**
 677 * Find the ranges of physical addresses that do not correspond to
 678 * e820 RAM areas and mark the corresponding pages as nosave for
 679 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
 680 *
 681 * This function requires the e820 map to be sorted and without any
 682 * overlapping entries and assumes the first e820 area to be RAM.
 683 */
 684void __init e820_mark_nosave_regions(unsigned long limit_pfn)
 685{
 686	int i;
 687	unsigned long pfn;
 688
 689	pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
 690	for (i = 1; i < e820.nr_map; i++) {
 691		struct e820entry *ei = &e820.map[i];
 692
 693		if (pfn < PFN_UP(ei->addr))
 694			register_nosave_region(pfn, PFN_UP(ei->addr));
 695
 696		pfn = PFN_DOWN(ei->addr + ei->size);
 697		if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
 698			register_nosave_region(PFN_UP(ei->addr), pfn);
 699
 700		if (pfn >= limit_pfn)
 701			break;
 702	}
 703}
 704#endif
 705
 706#ifdef CONFIG_ACPI
 707/**
 708 * Mark ACPI NVS memory region, so that we can save/restore it during
 709 * hibernation and the subsequent resume.
 710 */
 711static int __init e820_mark_nvs_memory(void)
 712{
 713	int i;
 714
 715	for (i = 0; i < e820.nr_map; i++) {
 716		struct e820entry *ei = &e820.map[i];
 717
 718		if (ei->type == E820_NVS)
 719			acpi_nvs_register(ei->addr, ei->size);
 720	}
 721
 722	return 0;
 723}
 724core_initcall(e820_mark_nvs_memory);
 725#endif
 726
 727/*
 728 * pre allocated 4k and reserved it in memblock and e820_saved
 729 */
 730u64 __init early_reserve_e820(u64 size, u64 align)
 731{
 
 732	u64 addr;
 
 733
 734	addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 735	if (addr) {
 736		e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED);
 737		printk(KERN_INFO "e820: update e820_saved for early_reserve_e820\n");
 738		update_e820_saved();
 
 739	}
 740
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 741	return addr;
 742}
 743
 744#ifdef CONFIG_X86_32
 745# ifdef CONFIG_X86_PAE
 746#  define MAX_ARCH_PFN		(1ULL<<(36-PAGE_SHIFT))
 747# else
 748#  define MAX_ARCH_PFN		(1ULL<<(32-PAGE_SHIFT))
 749# endif
 750#else /* CONFIG_X86_32 */
 751# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
 752#endif
 753
 754/*
 755 * Find the highest page frame number we have available
 756 */
 757static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
 758{
 759	int i;
 760	unsigned long last_pfn = 0;
 761	unsigned long max_arch_pfn = MAX_ARCH_PFN;
 762
 763	for (i = 0; i < e820.nr_map; i++) {
 764		struct e820entry *ei = &e820.map[i];
 765		unsigned long start_pfn;
 766		unsigned long end_pfn;
 767
 768		if (ei->type != type)
 769			continue;
 770
 771		start_pfn = ei->addr >> PAGE_SHIFT;
 772		end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
 773
 774		if (start_pfn >= limit_pfn)
 775			continue;
 776		if (end_pfn > limit_pfn) {
 777			last_pfn = limit_pfn;
 778			break;
 779		}
 780		if (end_pfn > last_pfn)
 781			last_pfn = end_pfn;
 782	}
 783
 784	if (last_pfn > max_arch_pfn)
 785		last_pfn = max_arch_pfn;
 786
 787	printk(KERN_INFO "e820: last_pfn = %#lx max_arch_pfn = %#lx\n",
 788			 last_pfn, max_arch_pfn);
 789	return last_pfn;
 790}
 791unsigned long __init e820_end_of_ram_pfn(void)
 792{
 793	return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
 794}
 795
 796unsigned long __init e820_end_of_low_ram_pfn(void)
 797{
 798	return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
 799}
 800
 801static void early_panic(char *msg)
 802{
 803	early_printk(msg);
 804	panic(msg);
 805}
 806
 807static int userdef __initdata;
 808
 809/* "mem=nopentium" disables the 4MB page tables. */
 810static int __init parse_memopt(char *p)
 811{
 812	u64 mem_size;
 813
 814	if (!p)
 815		return -EINVAL;
 816
 817	if (!strcmp(p, "nopentium")) {
 818#ifdef CONFIG_X86_32
 819		setup_clear_cpu_cap(X86_FEATURE_PSE);
 820		return 0;
 821#else
 822		printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
 823		return -EINVAL;
 824#endif
 825	}
 826
 827	userdef = 1;
 828	mem_size = memparse(p, &p);
 829	/* don't remove all of memory when handling "mem={invalid}" param */
 830	if (mem_size == 0)
 831		return -EINVAL;
 832	e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
 833
 834	return 0;
 835}
 836early_param("mem", parse_memopt);
 837
 838static int __init parse_memmap_opt(char *p)
 839{
 840	char *oldp;
 841	u64 start_at, mem_size;
 842
 843	if (!p)
 844		return -EINVAL;
 845
 846	if (!strncmp(p, "exactmap", 8)) {
 847#ifdef CONFIG_CRASH_DUMP
 848		/*
 849		 * If we are doing a crash dump, we still need to know
 850		 * the real mem size before original memory map is
 851		 * reset.
 852		 */
 853		saved_max_pfn = e820_end_of_ram_pfn();
 854#endif
 855		e820.nr_map = 0;
 856		userdef = 1;
 857		return 0;
 858	}
 859
 860	oldp = p;
 861	mem_size = memparse(p, &p);
 862	if (p == oldp)
 863		return -EINVAL;
 864
 865	userdef = 1;
 866	if (*p == '@') {
 867		start_at = memparse(p+1, &p);
 868		e820_add_region(start_at, mem_size, E820_RAM);
 869	} else if (*p == '#') {
 870		start_at = memparse(p+1, &p);
 871		e820_add_region(start_at, mem_size, E820_ACPI);
 872	} else if (*p == '$') {
 873		start_at = memparse(p+1, &p);
 874		e820_add_region(start_at, mem_size, E820_RESERVED);
 875	} else
 876		e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
 877
 878	return *p == '\0' ? 0 : -EINVAL;
 879}
 880early_param("memmap", parse_memmap_opt);
 881
 882void __init finish_e820_parsing(void)
 883{
 884	if (userdef) {
 885		u32 nr = e820.nr_map;
 886
 887		if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
 888			early_panic("Invalid user supplied memory map");
 889		e820.nr_map = nr;
 890
 891		printk(KERN_INFO "e820: user-defined physical RAM map:\n");
 892		e820_print_map("user");
 893	}
 894}
 895
 896static inline const char *e820_type_to_string(int e820_type)
 897{
 898	switch (e820_type) {
 899	case E820_RESERVED_KERN:
 900	case E820_RAM:	return "System RAM";
 901	case E820_ACPI:	return "ACPI Tables";
 902	case E820_NVS:	return "ACPI Non-volatile Storage";
 903	case E820_UNUSABLE:	return "Unusable memory";
 904	default:	return "reserved";
 905	}
 906}
 907
 908/*
 909 * Mark e820 reserved areas as busy for the resource manager.
 910 */
 911static struct resource __initdata *e820_res;
 912void __init e820_reserve_resources(void)
 913{
 914	int i;
 915	struct resource *res;
 916	u64 end;
 917
 918	res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
 919	e820_res = res;
 920	for (i = 0; i < e820.nr_map; i++) {
 921		end = e820.map[i].addr + e820.map[i].size - 1;
 922		if (end != (resource_size_t)end) {
 923			res++;
 924			continue;
 925		}
 926		res->name = e820_type_to_string(e820.map[i].type);
 927		res->start = e820.map[i].addr;
 928		res->end = end;
 929
 930		res->flags = IORESOURCE_MEM;
 931
 932		/*
 933		 * don't register the region that could be conflicted with
 934		 * pci device BAR resource and insert them later in
 935		 * pcibios_resource_survey()
 936		 */
 937		if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
 938			res->flags |= IORESOURCE_BUSY;
 939			insert_resource(&iomem_resource, res);
 940		}
 941		res++;
 942	}
 943
 944	for (i = 0; i < e820_saved.nr_map; i++) {
 945		struct e820entry *entry = &e820_saved.map[i];
 946		firmware_map_add_early(entry->addr,
 947			entry->addr + entry->size - 1,
 948			e820_type_to_string(entry->type));
 949	}
 950}
 951
 952/* How much should we pad RAM ending depending on where it is? */
 953static unsigned long ram_alignment(resource_size_t pos)
 954{
 955	unsigned long mb = pos >> 20;
 956
 957	/* To 64kB in the first megabyte */
 958	if (!mb)
 959		return 64*1024;
 960
 961	/* To 1MB in the first 16MB */
 962	if (mb < 16)
 963		return 1024*1024;
 964
 965	/* To 64MB for anything above that */
 966	return 64*1024*1024;
 967}
 968
 969#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
 970
 971void __init e820_reserve_resources_late(void)
 972{
 973	int i;
 974	struct resource *res;
 975
 976	res = e820_res;
 977	for (i = 0; i < e820.nr_map; i++) {
 978		if (!res->parent && res->end)
 979			insert_resource_expand_to_fit(&iomem_resource, res);
 980		res++;
 981	}
 982
 983	/*
 984	 * Try to bump up RAM regions to reasonable boundaries to
 985	 * avoid stolen RAM:
 986	 */
 987	for (i = 0; i < e820.nr_map; i++) {
 988		struct e820entry *entry = &e820.map[i];
 989		u64 start, end;
 990
 991		if (entry->type != E820_RAM)
 992			continue;
 993		start = entry->addr + entry->size;
 994		end = round_up(start, ram_alignment(start)) - 1;
 995		if (end > MAX_RESOURCE_SIZE)
 996			end = MAX_RESOURCE_SIZE;
 997		if (start >= end)
 998			continue;
 999		printk(KERN_DEBUG
1000		       "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n",
1001		       start, end);
1002		reserve_region_with_split(&iomem_resource, start, end,
1003					  "RAM buffer");
1004	}
1005}
1006
1007char *__init default_machine_specific_memory_setup(void)
1008{
1009	char *who = "BIOS-e820";
1010	u32 new_nr;
1011	/*
1012	 * Try to copy the BIOS-supplied E820-map.
1013	 *
1014	 * Otherwise fake a memory map; one section from 0k->640k,
1015	 * the next section from 1mb->appropriate_mem_k
1016	 */
1017	new_nr = boot_params.e820_entries;
1018	sanitize_e820_map(boot_params.e820_map,
1019			ARRAY_SIZE(boot_params.e820_map),
1020			&new_nr);
1021	boot_params.e820_entries = new_nr;
1022	if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1023	  < 0) {
1024		u64 mem_size;
1025
1026		/* compare results from other methods and take the greater */
1027		if (boot_params.alt_mem_k
1028		    < boot_params.screen_info.ext_mem_k) {
1029			mem_size = boot_params.screen_info.ext_mem_k;
1030			who = "BIOS-88";
1031		} else {
1032			mem_size = boot_params.alt_mem_k;
1033			who = "BIOS-e801";
1034		}
1035
1036		e820.nr_map = 0;
1037		e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1038		e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1039	}
1040
1041	/* In case someone cares... */
1042	return who;
1043}
1044
1045void __init setup_memory_map(void)
1046{
1047	char *who;
1048
1049	who = x86_init.resources.memory_setup();
1050	memcpy(&e820_saved, &e820, sizeof(struct e820map));
1051	printk(KERN_INFO "e820: BIOS-provided physical RAM map:\n");
1052	e820_print_map(who);
1053}
1054
1055void __init memblock_x86_fill(void)
1056{
1057	int i;
1058	u64 end;
1059
1060	/*
1061	 * EFI may have more than 128 entries
1062	 * We are safe to enable resizing, beause memblock_x86_fill()
1063	 * is rather later for x86
1064	 */
1065	memblock_allow_resize();
1066
1067	for (i = 0; i < e820.nr_map; i++) {
1068		struct e820entry *ei = &e820.map[i];
1069
1070		end = ei->addr + ei->size;
1071		if (end != (resource_size_t)end)
1072			continue;
1073
1074		if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1075			continue;
1076
1077		memblock_add(ei->addr, ei->size);
1078	}
1079
 
1080	memblock_dump_all();
1081}
1082
1083void __init memblock_find_dma_reserve(void)
1084{
1085#ifdef CONFIG_X86_64
1086	u64 nr_pages = 0, nr_free_pages = 0;
1087	unsigned long start_pfn, end_pfn;
1088	phys_addr_t start, end;
1089	int i;
1090	u64 u;
1091
1092	/*
1093	 * need to find out used area below MAX_DMA_PFN
1094	 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1095	 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1096	 */
1097	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
1098		start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN);
1099		end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN);
1100		nr_pages += end_pfn - start_pfn;
1101	}
1102
1103	for_each_free_mem_range(u, MAX_NUMNODES, &start, &end, NULL) {
1104		start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
1105		end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
1106		if (start_pfn < end_pfn)
1107			nr_free_pages += end_pfn - start_pfn;
1108	}
1109
1110	set_dma_reserve(nr_pages - nr_free_pages);
1111#endif
1112}
v3.1
   1/*
   2 * Handle the memory map.
   3 * The functions here do the job until bootmem takes over.
   4 *
   5 *  Getting sanitize_e820_map() in sync with i386 version by applying change:
   6 *  -  Provisions for empty E820 memory regions (reported by certain BIOSes).
   7 *     Alex Achenbach <xela@slit.de>, December 2002.
   8 *  Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
   9 *
  10 */
  11#include <linux/kernel.h>
  12#include <linux/types.h>
  13#include <linux/init.h>
  14#include <linux/crash_dump.h>
 
  15#include <linux/bootmem.h>
  16#include <linux/pfn.h>
  17#include <linux/suspend.h>
  18#include <linux/acpi.h>
  19#include <linux/firmware-map.h>
  20#include <linux/memblock.h>
 
  21
  22#include <asm/e820.h>
  23#include <asm/proto.h>
  24#include <asm/setup.h>
  25
  26/*
  27 * The e820 map is the map that gets modified e.g. with command line parameters
  28 * and that is also registered with modifications in the kernel resource tree
  29 * with the iomem_resource as parent.
  30 *
  31 * The e820_saved is directly saved after the BIOS-provided memory map is
  32 * copied. It doesn't get modified afterwards. It's registered for the
  33 * /sys/firmware/memmap interface.
  34 *
  35 * That memory map is not modified and is used as base for kexec. The kexec'd
  36 * kernel should get the same memory map as the firmware provides. Then the
  37 * user can e.g. boot the original kernel with mem=1G while still booting the
  38 * next kernel with full memory.
  39 */
  40struct e820map e820;
  41struct e820map e820_saved;
  42
  43/* For PCI or other memory-mapped resources */
  44unsigned long pci_mem_start = 0xaeedbabe;
  45#ifdef CONFIG_PCI
  46EXPORT_SYMBOL(pci_mem_start);
  47#endif
  48
  49/*
  50 * This function checks if any part of the range <start,end> is mapped
  51 * with type.
  52 */
  53int
  54e820_any_mapped(u64 start, u64 end, unsigned type)
  55{
  56	int i;
  57
  58	for (i = 0; i < e820.nr_map; i++) {
  59		struct e820entry *ei = &e820.map[i];
  60
  61		if (type && ei->type != type)
  62			continue;
  63		if (ei->addr >= end || ei->addr + ei->size <= start)
  64			continue;
  65		return 1;
  66	}
  67	return 0;
  68}
  69EXPORT_SYMBOL_GPL(e820_any_mapped);
  70
  71/*
  72 * This function checks if the entire range <start,end> is mapped with type.
  73 *
  74 * Note: this function only works correct if the e820 table is sorted and
  75 * not-overlapping, which is the case
  76 */
  77int __init e820_all_mapped(u64 start, u64 end, unsigned type)
  78{
  79	int i;
  80
  81	for (i = 0; i < e820.nr_map; i++) {
  82		struct e820entry *ei = &e820.map[i];
  83
  84		if (type && ei->type != type)
  85			continue;
  86		/* is the region (part) in overlap with the current region ?*/
  87		if (ei->addr >= end || ei->addr + ei->size <= start)
  88			continue;
  89
  90		/* if the region is at the beginning of <start,end> we move
  91		 * start to the end of the region since it's ok until there
  92		 */
  93		if (ei->addr <= start)
  94			start = ei->addr + ei->size;
  95		/*
  96		 * if start is now at or beyond end, we're done, full
  97		 * coverage
  98		 */
  99		if (start >= end)
 100			return 1;
 101	}
 102	return 0;
 103}
 104
 105/*
 106 * Add a memory region to the kernel e820 map.
 107 */
 108static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
 109					 int type)
 110{
 111	int x = e820x->nr_map;
 112
 113	if (x >= ARRAY_SIZE(e820x->map)) {
 114		printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
 
 
 115		return;
 116	}
 117
 118	e820x->map[x].addr = start;
 119	e820x->map[x].size = size;
 120	e820x->map[x].type = type;
 121	e820x->nr_map++;
 122}
 123
 124void __init e820_add_region(u64 start, u64 size, int type)
 125{
 126	__e820_add_region(&e820, start, size, type);
 127}
 128
 129static void __init e820_print_type(u32 type)
 130{
 131	switch (type) {
 132	case E820_RAM:
 133	case E820_RESERVED_KERN:
 134		printk(KERN_CONT "(usable)");
 135		break;
 136	case E820_RESERVED:
 137		printk(KERN_CONT "(reserved)");
 138		break;
 139	case E820_ACPI:
 140		printk(KERN_CONT "(ACPI data)");
 141		break;
 142	case E820_NVS:
 143		printk(KERN_CONT "(ACPI NVS)");
 144		break;
 145	case E820_UNUSABLE:
 146		printk(KERN_CONT "(unusable)");
 147		break;
 148	default:
 149		printk(KERN_CONT "type %u", type);
 150		break;
 151	}
 152}
 153
 154void __init e820_print_map(char *who)
 155{
 156	int i;
 157
 158	for (i = 0; i < e820.nr_map; i++) {
 159		printk(KERN_INFO " %s: %016Lx - %016Lx ", who,
 160		       (unsigned long long) e820.map[i].addr,
 161		       (unsigned long long)
 162		       (e820.map[i].addr + e820.map[i].size));
 163		e820_print_type(e820.map[i].type);
 164		printk(KERN_CONT "\n");
 165	}
 166}
 167
 168/*
 169 * Sanitize the BIOS e820 map.
 170 *
 171 * Some e820 responses include overlapping entries. The following
 172 * replaces the original e820 map with a new one, removing overlaps,
 173 * and resolving conflicting memory types in favor of highest
 174 * numbered type.
 175 *
 176 * The input parameter biosmap points to an array of 'struct
 177 * e820entry' which on entry has elements in the range [0, *pnr_map)
 178 * valid, and which has space for up to max_nr_map entries.
 179 * On return, the resulting sanitized e820 map entries will be in
 180 * overwritten in the same location, starting at biosmap.
 181 *
 182 * The integer pointed to by pnr_map must be valid on entry (the
 183 * current number of valid entries located at biosmap) and will
 184 * be updated on return, with the new number of valid entries
 185 * (something no more than max_nr_map.)
 186 *
 187 * The return value from sanitize_e820_map() is zero if it
 188 * successfully 'sanitized' the map entries passed in, and is -1
 189 * if it did nothing, which can happen if either of (1) it was
 190 * only passed one map entry, or (2) any of the input map entries
 191 * were invalid (start + size < start, meaning that the size was
 192 * so big the described memory range wrapped around through zero.)
 193 *
 194 *	Visually we're performing the following
 195 *	(1,2,3,4 = memory types)...
 196 *
 197 *	Sample memory map (w/overlaps):
 198 *	   ____22__________________
 199 *	   ______________________4_
 200 *	   ____1111________________
 201 *	   _44_____________________
 202 *	   11111111________________
 203 *	   ____________________33__
 204 *	   ___________44___________
 205 *	   __________33333_________
 206 *	   ______________22________
 207 *	   ___________________2222_
 208 *	   _________111111111______
 209 *	   _____________________11_
 210 *	   _________________4______
 211 *
 212 *	Sanitized equivalent (no overlap):
 213 *	   1_______________________
 214 *	   _44_____________________
 215 *	   ___1____________________
 216 *	   ____22__________________
 217 *	   ______11________________
 218 *	   _________1______________
 219 *	   __________3_____________
 220 *	   ___________44___________
 221 *	   _____________33_________
 222 *	   _______________2________
 223 *	   ________________1_______
 224 *	   _________________4______
 225 *	   ___________________2____
 226 *	   ____________________33__
 227 *	   ______________________4_
 228 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 229
 230int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
 231			     u32 *pnr_map)
 232{
 233	struct change_member {
 234		struct e820entry *pbios; /* pointer to original bios entry */
 235		unsigned long long addr; /* address for this change point */
 236	};
 237	static struct change_member change_point_list[2*E820_X_MAX] __initdata;
 238	static struct change_member *change_point[2*E820_X_MAX] __initdata;
 239	static struct e820entry *overlap_list[E820_X_MAX] __initdata;
 240	static struct e820entry new_bios[E820_X_MAX] __initdata;
 241	struct change_member *change_tmp;
 242	unsigned long current_type, last_type;
 243	unsigned long long last_addr;
 244	int chgidx, still_changing;
 245	int overlap_entries;
 246	int new_bios_entry;
 247	int old_nr, new_nr, chg_nr;
 248	int i;
 249
 250	/* if there's only one memory region, don't bother */
 251	if (*pnr_map < 2)
 252		return -1;
 253
 254	old_nr = *pnr_map;
 255	BUG_ON(old_nr > max_nr_map);
 256
 257	/* bail out if we find any unreasonable addresses in bios map */
 258	for (i = 0; i < old_nr; i++)
 259		if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
 260			return -1;
 261
 262	/* create pointers for initial change-point information (for sorting) */
 263	for (i = 0; i < 2 * old_nr; i++)
 264		change_point[i] = &change_point_list[i];
 265
 266	/* record all known change-points (starting and ending addresses),
 267	   omitting those that are for empty memory regions */
 268	chgidx = 0;
 269	for (i = 0; i < old_nr; i++)	{
 270		if (biosmap[i].size != 0) {
 271			change_point[chgidx]->addr = biosmap[i].addr;
 272			change_point[chgidx++]->pbios = &biosmap[i];
 273			change_point[chgidx]->addr = biosmap[i].addr +
 274				biosmap[i].size;
 275			change_point[chgidx++]->pbios = &biosmap[i];
 276		}
 277	}
 278	chg_nr = chgidx;
 279
 280	/* sort change-point list by memory addresses (low -> high) */
 281	still_changing = 1;
 282	while (still_changing)	{
 283		still_changing = 0;
 284		for (i = 1; i < chg_nr; i++)  {
 285			unsigned long long curaddr, lastaddr;
 286			unsigned long long curpbaddr, lastpbaddr;
 287
 288			curaddr = change_point[i]->addr;
 289			lastaddr = change_point[i - 1]->addr;
 290			curpbaddr = change_point[i]->pbios->addr;
 291			lastpbaddr = change_point[i - 1]->pbios->addr;
 292
 293			/*
 294			 * swap entries, when:
 295			 *
 296			 * curaddr > lastaddr or
 297			 * curaddr == lastaddr and curaddr == curpbaddr and
 298			 * lastaddr != lastpbaddr
 299			 */
 300			if (curaddr < lastaddr ||
 301			    (curaddr == lastaddr && curaddr == curpbaddr &&
 302			     lastaddr != lastpbaddr)) {
 303				change_tmp = change_point[i];
 304				change_point[i] = change_point[i-1];
 305				change_point[i-1] = change_tmp;
 306				still_changing = 1;
 307			}
 308		}
 309	}
 310
 311	/* create a new bios memory map, removing overlaps */
 312	overlap_entries = 0;	 /* number of entries in the overlap table */
 313	new_bios_entry = 0;	 /* index for creating new bios map entries */
 314	last_type = 0;		 /* start with undefined memory type */
 315	last_addr = 0;		 /* start with 0 as last starting address */
 316
 317	/* loop through change-points, determining affect on the new bios map */
 318	for (chgidx = 0; chgidx < chg_nr; chgidx++) {
 319		/* keep track of all overlapping bios entries */
 320		if (change_point[chgidx]->addr ==
 321		    change_point[chgidx]->pbios->addr) {
 322			/*
 323			 * add map entry to overlap list (> 1 entry
 324			 * implies an overlap)
 325			 */
 326			overlap_list[overlap_entries++] =
 327				change_point[chgidx]->pbios;
 328		} else {
 329			/*
 330			 * remove entry from list (order independent,
 331			 * so swap with last)
 332			 */
 333			for (i = 0; i < overlap_entries; i++) {
 334				if (overlap_list[i] ==
 335				    change_point[chgidx]->pbios)
 336					overlap_list[i] =
 337						overlap_list[overlap_entries-1];
 338			}
 339			overlap_entries--;
 340		}
 341		/*
 342		 * if there are overlapping entries, decide which
 343		 * "type" to use (larger value takes precedence --
 344		 * 1=usable, 2,3,4,4+=unusable)
 345		 */
 346		current_type = 0;
 347		for (i = 0; i < overlap_entries; i++)
 348			if (overlap_list[i]->type > current_type)
 349				current_type = overlap_list[i]->type;
 350		/*
 351		 * continue building up new bios map based on this
 352		 * information
 353		 */
 354		if (current_type != last_type)	{
 355			if (last_type != 0)	 {
 356				new_bios[new_bios_entry].size =
 357					change_point[chgidx]->addr - last_addr;
 358				/*
 359				 * move forward only if the new size
 360				 * was non-zero
 361				 */
 362				if (new_bios[new_bios_entry].size != 0)
 363					/*
 364					 * no more space left for new
 365					 * bios entries ?
 366					 */
 367					if (++new_bios_entry >= max_nr_map)
 368						break;
 369			}
 370			if (current_type != 0)	{
 371				new_bios[new_bios_entry].addr =
 372					change_point[chgidx]->addr;
 373				new_bios[new_bios_entry].type = current_type;
 374				last_addr = change_point[chgidx]->addr;
 375			}
 376			last_type = current_type;
 377		}
 378	}
 379	/* retain count for new bios entries */
 380	new_nr = new_bios_entry;
 381
 382	/* copy new bios mapping into original location */
 383	memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
 384	*pnr_map = new_nr;
 385
 386	return 0;
 387}
 388
 389static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
 390{
 391	while (nr_map) {
 392		u64 start = biosmap->addr;
 393		u64 size = biosmap->size;
 394		u64 end = start + size;
 395		u32 type = biosmap->type;
 396
 397		/* Overflow in 64 bits? Ignore the memory map. */
 398		if (start > end)
 399			return -1;
 400
 401		e820_add_region(start, size, type);
 402
 403		biosmap++;
 404		nr_map--;
 405	}
 406	return 0;
 407}
 408
 409/*
 410 * Copy the BIOS e820 map into a safe place.
 411 *
 412 * Sanity-check it while we're at it..
 413 *
 414 * If we're lucky and live on a modern system, the setup code
 415 * will have given us a memory map that we can use to properly
 416 * set up memory.  If we aren't, we'll fake a memory map.
 417 */
 418static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
 419{
 420	/* Only one memory region (or negative)? Ignore it */
 421	if (nr_map < 2)
 422		return -1;
 423
 424	return __append_e820_map(biosmap, nr_map);
 425}
 426
 427static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
 428					u64 size, unsigned old_type,
 429					unsigned new_type)
 430{
 431	u64 end;
 432	unsigned int i;
 433	u64 real_updated_size = 0;
 434
 435	BUG_ON(old_type == new_type);
 436
 437	if (size > (ULLONG_MAX - start))
 438		size = ULLONG_MAX - start;
 439
 440	end = start + size;
 441	printk(KERN_DEBUG "e820 update range: %016Lx - %016Lx ",
 442		       (unsigned long long) start,
 443		       (unsigned long long) end);
 444	e820_print_type(old_type);
 445	printk(KERN_CONT " ==> ");
 446	e820_print_type(new_type);
 447	printk(KERN_CONT "\n");
 448
 449	for (i = 0; i < e820x->nr_map; i++) {
 450		struct e820entry *ei = &e820x->map[i];
 451		u64 final_start, final_end;
 452		u64 ei_end;
 453
 454		if (ei->type != old_type)
 455			continue;
 456
 457		ei_end = ei->addr + ei->size;
 458		/* totally covered by new range? */
 459		if (ei->addr >= start && ei_end <= end) {
 460			ei->type = new_type;
 461			real_updated_size += ei->size;
 462			continue;
 463		}
 464
 465		/* new range is totally covered? */
 466		if (ei->addr < start && ei_end > end) {
 467			__e820_add_region(e820x, start, size, new_type);
 468			__e820_add_region(e820x, end, ei_end - end, ei->type);
 469			ei->size = start - ei->addr;
 470			real_updated_size += size;
 471			continue;
 472		}
 473
 474		/* partially covered */
 475		final_start = max(start, ei->addr);
 476		final_end = min(end, ei_end);
 477		if (final_start >= final_end)
 478			continue;
 479
 480		__e820_add_region(e820x, final_start, final_end - final_start,
 481				  new_type);
 482
 483		real_updated_size += final_end - final_start;
 484
 485		/*
 486		 * left range could be head or tail, so need to update
 487		 * size at first.
 488		 */
 489		ei->size -= final_end - final_start;
 490		if (ei->addr < final_start)
 491			continue;
 492		ei->addr = final_end;
 493	}
 494	return real_updated_size;
 495}
 496
 497u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
 498			     unsigned new_type)
 499{
 500	return __e820_update_range(&e820, start, size, old_type, new_type);
 501}
 502
 503static u64 __init e820_update_range_saved(u64 start, u64 size,
 504					  unsigned old_type, unsigned new_type)
 505{
 506	return __e820_update_range(&e820_saved, start, size, old_type,
 507				     new_type);
 508}
 509
 510/* make e820 not cover the range */
 511u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
 512			     int checktype)
 513{
 514	int i;
 515	u64 end;
 516	u64 real_removed_size = 0;
 517
 518	if (size > (ULLONG_MAX - start))
 519		size = ULLONG_MAX - start;
 520
 521	end = start + size;
 522	printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
 523		       (unsigned long long) start,
 524		       (unsigned long long) end);
 525	if (checktype)
 526		e820_print_type(old_type);
 527	printk(KERN_CONT "\n");
 528
 529	for (i = 0; i < e820.nr_map; i++) {
 530		struct e820entry *ei = &e820.map[i];
 531		u64 final_start, final_end;
 532		u64 ei_end;
 533
 534		if (checktype && ei->type != old_type)
 535			continue;
 536
 537		ei_end = ei->addr + ei->size;
 538		/* totally covered? */
 539		if (ei->addr >= start && ei_end <= end) {
 540			real_removed_size += ei->size;
 541			memset(ei, 0, sizeof(struct e820entry));
 542			continue;
 543		}
 544
 545		/* new range is totally covered? */
 546		if (ei->addr < start && ei_end > end) {
 547			e820_add_region(end, ei_end - end, ei->type);
 548			ei->size = start - ei->addr;
 549			real_removed_size += size;
 550			continue;
 551		}
 552
 553		/* partially covered */
 554		final_start = max(start, ei->addr);
 555		final_end = min(end, ei_end);
 556		if (final_start >= final_end)
 557			continue;
 558		real_removed_size += final_end - final_start;
 559
 560		/*
 561		 * left range could be head or tail, so need to update
 562		 * size at first.
 563		 */
 564		ei->size -= final_end - final_start;
 565		if (ei->addr < final_start)
 566			continue;
 567		ei->addr = final_end;
 568	}
 569	return real_removed_size;
 570}
 571
 572void __init update_e820(void)
 573{
 574	u32 nr_map;
 575
 576	nr_map = e820.nr_map;
 577	if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
 578		return;
 579	e820.nr_map = nr_map;
 580	printk(KERN_INFO "modified physical RAM map:\n");
 581	e820_print_map("modified");
 582}
 583static void __init update_e820_saved(void)
 584{
 585	u32 nr_map;
 586
 587	nr_map = e820_saved.nr_map;
 588	if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
 589		return;
 590	e820_saved.nr_map = nr_map;
 591}
 592#define MAX_GAP_END 0x100000000ull
 593/*
 594 * Search for a gap in the e820 memory space from start_addr to end_addr.
 595 */
 596__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
 597		unsigned long start_addr, unsigned long long end_addr)
 598{
 599	unsigned long long last;
 600	int i = e820.nr_map;
 601	int found = 0;
 602
 603	last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
 604
 605	while (--i >= 0) {
 606		unsigned long long start = e820.map[i].addr;
 607		unsigned long long end = start + e820.map[i].size;
 608
 609		if (end < start_addr)
 610			continue;
 611
 612		/*
 613		 * Since "last" is at most 4GB, we know we'll
 614		 * fit in 32 bits if this condition is true
 615		 */
 616		if (last > end) {
 617			unsigned long gap = last - end;
 618
 619			if (gap >= *gapsize) {
 620				*gapsize = gap;
 621				*gapstart = end;
 622				found = 1;
 623			}
 624		}
 625		if (start < last)
 626			last = start;
 627	}
 628	return found;
 629}
 630
 631/*
 632 * Search for the biggest gap in the low 32 bits of the e820
 633 * memory space.  We pass this space to PCI to assign MMIO resources
 634 * for hotplug or unconfigured devices in.
 635 * Hopefully the BIOS let enough space left.
 636 */
 637__init void e820_setup_gap(void)
 638{
 639	unsigned long gapstart, gapsize;
 640	int found;
 641
 642	gapstart = 0x10000000;
 643	gapsize = 0x400000;
 644	found  = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
 645
 646#ifdef CONFIG_X86_64
 647	if (!found) {
 648		gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
 649		printk(KERN_ERR
 650	"PCI: Warning: Cannot find a gap in the 32bit address range\n"
 651	"PCI: Unassigned devices with 32bit resource registers may break!\n");
 652	}
 653#endif
 654
 655	/*
 656	 * e820_reserve_resources_late protect stolen RAM already
 657	 */
 658	pci_mem_start = gapstart;
 659
 660	printk(KERN_INFO
 661	       "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
 662	       pci_mem_start, gapstart, gapsize);
 663}
 664
 665/**
 666 * Because of the size limitation of struct boot_params, only first
 667 * 128 E820 memory entries are passed to kernel via
 668 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
 669 * linked list of struct setup_data, which is parsed here.
 670 */
 671void __init parse_e820_ext(struct setup_data *sdata)
 672{
 673	int entries;
 674	struct e820entry *extmap;
 675
 676	entries = sdata->len / sizeof(struct e820entry);
 677	extmap = (struct e820entry *)(sdata->data);
 678	__append_e820_map(extmap, entries);
 679	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 680	printk(KERN_INFO "extended physical RAM map:\n");
 681	e820_print_map("extended");
 682}
 683
 684#if defined(CONFIG_X86_64) || \
 685	(defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
 686/**
 687 * Find the ranges of physical addresses that do not correspond to
 688 * e820 RAM areas and mark the corresponding pages as nosave for
 689 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
 690 *
 691 * This function requires the e820 map to be sorted and without any
 692 * overlapping entries and assumes the first e820 area to be RAM.
 693 */
 694void __init e820_mark_nosave_regions(unsigned long limit_pfn)
 695{
 696	int i;
 697	unsigned long pfn;
 698
 699	pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
 700	for (i = 1; i < e820.nr_map; i++) {
 701		struct e820entry *ei = &e820.map[i];
 702
 703		if (pfn < PFN_UP(ei->addr))
 704			register_nosave_region(pfn, PFN_UP(ei->addr));
 705
 706		pfn = PFN_DOWN(ei->addr + ei->size);
 707		if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
 708			register_nosave_region(PFN_UP(ei->addr), pfn);
 709
 710		if (pfn >= limit_pfn)
 711			break;
 712	}
 713}
 714#endif
 715
 716#ifdef CONFIG_HIBERNATION
 717/**
 718 * Mark ACPI NVS memory region, so that we can save/restore it during
 719 * hibernation and the subsequent resume.
 720 */
 721static int __init e820_mark_nvs_memory(void)
 722{
 723	int i;
 724
 725	for (i = 0; i < e820.nr_map; i++) {
 726		struct e820entry *ei = &e820.map[i];
 727
 728		if (ei->type == E820_NVS)
 729			suspend_nvs_register(ei->addr, ei->size);
 730	}
 731
 732	return 0;
 733}
 734core_initcall(e820_mark_nvs_memory);
 735#endif
 736
 737/*
 738 * pre allocated 4k and reserved it in memblock and e820_saved
 739 */
 740u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
 741{
 742	u64 size = 0;
 743	u64 addr;
 744	u64 start;
 745
 746	for (start = startt; ; start += size) {
 747		start = memblock_x86_find_in_range_size(start, &size, align);
 748		if (start == MEMBLOCK_ERROR)
 749			return 0;
 750		if (size >= sizet)
 751			break;
 752	}
 753
 754#ifdef CONFIG_X86_32
 755	if (start >= MAXMEM)
 756		return 0;
 757	if (start + size > MAXMEM)
 758		size = MAXMEM - start;
 759#endif
 760
 761	addr = round_down(start + size - sizet, align);
 762	if (addr < start)
 763		return 0;
 764	memblock_x86_reserve_range(addr, addr + sizet, "new next");
 765	e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
 766	printk(KERN_INFO "update e820_saved for early_reserve_e820\n");
 767	update_e820_saved();
 768
 769	return addr;
 770}
 771
 772#ifdef CONFIG_X86_32
 773# ifdef CONFIG_X86_PAE
 774#  define MAX_ARCH_PFN		(1ULL<<(36-PAGE_SHIFT))
 775# else
 776#  define MAX_ARCH_PFN		(1ULL<<(32-PAGE_SHIFT))
 777# endif
 778#else /* CONFIG_X86_32 */
 779# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
 780#endif
 781
 782/*
 783 * Find the highest page frame number we have available
 784 */
 785static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
 786{
 787	int i;
 788	unsigned long last_pfn = 0;
 789	unsigned long max_arch_pfn = MAX_ARCH_PFN;
 790
 791	for (i = 0; i < e820.nr_map; i++) {
 792		struct e820entry *ei = &e820.map[i];
 793		unsigned long start_pfn;
 794		unsigned long end_pfn;
 795
 796		if (ei->type != type)
 797			continue;
 798
 799		start_pfn = ei->addr >> PAGE_SHIFT;
 800		end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
 801
 802		if (start_pfn >= limit_pfn)
 803			continue;
 804		if (end_pfn > limit_pfn) {
 805			last_pfn = limit_pfn;
 806			break;
 807		}
 808		if (end_pfn > last_pfn)
 809			last_pfn = end_pfn;
 810	}
 811
 812	if (last_pfn > max_arch_pfn)
 813		last_pfn = max_arch_pfn;
 814
 815	printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
 816			 last_pfn, max_arch_pfn);
 817	return last_pfn;
 818}
 819unsigned long __init e820_end_of_ram_pfn(void)
 820{
 821	return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
 822}
 823
 824unsigned long __init e820_end_of_low_ram_pfn(void)
 825{
 826	return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
 827}
 828
 829static void early_panic(char *msg)
 830{
 831	early_printk(msg);
 832	panic(msg);
 833}
 834
 835static int userdef __initdata;
 836
 837/* "mem=nopentium" disables the 4MB page tables. */
 838static int __init parse_memopt(char *p)
 839{
 840	u64 mem_size;
 841
 842	if (!p)
 843		return -EINVAL;
 844
 845	if (!strcmp(p, "nopentium")) {
 846#ifdef CONFIG_X86_32
 847		setup_clear_cpu_cap(X86_FEATURE_PSE);
 848		return 0;
 849#else
 850		printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
 851		return -EINVAL;
 852#endif
 853	}
 854
 855	userdef = 1;
 856	mem_size = memparse(p, &p);
 857	/* don't remove all of memory when handling "mem={invalid}" param */
 858	if (mem_size == 0)
 859		return -EINVAL;
 860	e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
 861
 862	return 0;
 863}
 864early_param("mem", parse_memopt);
 865
 866static int __init parse_memmap_opt(char *p)
 867{
 868	char *oldp;
 869	u64 start_at, mem_size;
 870
 871	if (!p)
 872		return -EINVAL;
 873
 874	if (!strncmp(p, "exactmap", 8)) {
 875#ifdef CONFIG_CRASH_DUMP
 876		/*
 877		 * If we are doing a crash dump, we still need to know
 878		 * the real mem size before original memory map is
 879		 * reset.
 880		 */
 881		saved_max_pfn = e820_end_of_ram_pfn();
 882#endif
 883		e820.nr_map = 0;
 884		userdef = 1;
 885		return 0;
 886	}
 887
 888	oldp = p;
 889	mem_size = memparse(p, &p);
 890	if (p == oldp)
 891		return -EINVAL;
 892
 893	userdef = 1;
 894	if (*p == '@') {
 895		start_at = memparse(p+1, &p);
 896		e820_add_region(start_at, mem_size, E820_RAM);
 897	} else if (*p == '#') {
 898		start_at = memparse(p+1, &p);
 899		e820_add_region(start_at, mem_size, E820_ACPI);
 900	} else if (*p == '$') {
 901		start_at = memparse(p+1, &p);
 902		e820_add_region(start_at, mem_size, E820_RESERVED);
 903	} else
 904		e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
 905
 906	return *p == '\0' ? 0 : -EINVAL;
 907}
 908early_param("memmap", parse_memmap_opt);
 909
 910void __init finish_e820_parsing(void)
 911{
 912	if (userdef) {
 913		u32 nr = e820.nr_map;
 914
 915		if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
 916			early_panic("Invalid user supplied memory map");
 917		e820.nr_map = nr;
 918
 919		printk(KERN_INFO "user-defined physical RAM map:\n");
 920		e820_print_map("user");
 921	}
 922}
 923
 924static inline const char *e820_type_to_string(int e820_type)
 925{
 926	switch (e820_type) {
 927	case E820_RESERVED_KERN:
 928	case E820_RAM:	return "System RAM";
 929	case E820_ACPI:	return "ACPI Tables";
 930	case E820_NVS:	return "ACPI Non-volatile Storage";
 931	case E820_UNUSABLE:	return "Unusable memory";
 932	default:	return "reserved";
 933	}
 934}
 935
 936/*
 937 * Mark e820 reserved areas as busy for the resource manager.
 938 */
 939static struct resource __initdata *e820_res;
 940void __init e820_reserve_resources(void)
 941{
 942	int i;
 943	struct resource *res;
 944	u64 end;
 945
 946	res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
 947	e820_res = res;
 948	for (i = 0; i < e820.nr_map; i++) {
 949		end = e820.map[i].addr + e820.map[i].size - 1;
 950		if (end != (resource_size_t)end) {
 951			res++;
 952			continue;
 953		}
 954		res->name = e820_type_to_string(e820.map[i].type);
 955		res->start = e820.map[i].addr;
 956		res->end = end;
 957
 958		res->flags = IORESOURCE_MEM;
 959
 960		/*
 961		 * don't register the region that could be conflicted with
 962		 * pci device BAR resource and insert them later in
 963		 * pcibios_resource_survey()
 964		 */
 965		if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
 966			res->flags |= IORESOURCE_BUSY;
 967			insert_resource(&iomem_resource, res);
 968		}
 969		res++;
 970	}
 971
 972	for (i = 0; i < e820_saved.nr_map; i++) {
 973		struct e820entry *entry = &e820_saved.map[i];
 974		firmware_map_add_early(entry->addr,
 975			entry->addr + entry->size - 1,
 976			e820_type_to_string(entry->type));
 977	}
 978}
 979
 980/* How much should we pad RAM ending depending on where it is? */
 981static unsigned long ram_alignment(resource_size_t pos)
 982{
 983	unsigned long mb = pos >> 20;
 984
 985	/* To 64kB in the first megabyte */
 986	if (!mb)
 987		return 64*1024;
 988
 989	/* To 1MB in the first 16MB */
 990	if (mb < 16)
 991		return 1024*1024;
 992
 993	/* To 64MB for anything above that */
 994	return 64*1024*1024;
 995}
 996
 997#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
 998
 999void __init e820_reserve_resources_late(void)
1000{
1001	int i;
1002	struct resource *res;
1003
1004	res = e820_res;
1005	for (i = 0; i < e820.nr_map; i++) {
1006		if (!res->parent && res->end)
1007			insert_resource_expand_to_fit(&iomem_resource, res);
1008		res++;
1009	}
1010
1011	/*
1012	 * Try to bump up RAM regions to reasonable boundaries to
1013	 * avoid stolen RAM:
1014	 */
1015	for (i = 0; i < e820.nr_map; i++) {
1016		struct e820entry *entry = &e820.map[i];
1017		u64 start, end;
1018
1019		if (entry->type != E820_RAM)
1020			continue;
1021		start = entry->addr + entry->size;
1022		end = round_up(start, ram_alignment(start)) - 1;
1023		if (end > MAX_RESOURCE_SIZE)
1024			end = MAX_RESOURCE_SIZE;
1025		if (start >= end)
1026			continue;
1027		printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
1028			       start, end);
 
1029		reserve_region_with_split(&iomem_resource, start, end,
1030					  "RAM buffer");
1031	}
1032}
1033
1034char *__init default_machine_specific_memory_setup(void)
1035{
1036	char *who = "BIOS-e820";
1037	u32 new_nr;
1038	/*
1039	 * Try to copy the BIOS-supplied E820-map.
1040	 *
1041	 * Otherwise fake a memory map; one section from 0k->640k,
1042	 * the next section from 1mb->appropriate_mem_k
1043	 */
1044	new_nr = boot_params.e820_entries;
1045	sanitize_e820_map(boot_params.e820_map,
1046			ARRAY_SIZE(boot_params.e820_map),
1047			&new_nr);
1048	boot_params.e820_entries = new_nr;
1049	if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1050	  < 0) {
1051		u64 mem_size;
1052
1053		/* compare results from other methods and take the greater */
1054		if (boot_params.alt_mem_k
1055		    < boot_params.screen_info.ext_mem_k) {
1056			mem_size = boot_params.screen_info.ext_mem_k;
1057			who = "BIOS-88";
1058		} else {
1059			mem_size = boot_params.alt_mem_k;
1060			who = "BIOS-e801";
1061		}
1062
1063		e820.nr_map = 0;
1064		e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1065		e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1066	}
1067
1068	/* In case someone cares... */
1069	return who;
1070}
1071
1072void __init setup_memory_map(void)
1073{
1074	char *who;
1075
1076	who = x86_init.resources.memory_setup();
1077	memcpy(&e820_saved, &e820, sizeof(struct e820map));
1078	printk(KERN_INFO "BIOS-provided physical RAM map:\n");
1079	e820_print_map(who);
1080}
1081
1082void __init memblock_x86_fill(void)
1083{
1084	int i;
1085	u64 end;
1086
1087	/*
1088	 * EFI may have more than 128 entries
1089	 * We are safe to enable resizing, beause memblock_x86_fill()
1090	 * is rather later for x86
1091	 */
1092	memblock_can_resize = 1;
1093
1094	for (i = 0; i < e820.nr_map; i++) {
1095		struct e820entry *ei = &e820.map[i];
1096
1097		end = ei->addr + ei->size;
1098		if (end != (resource_size_t)end)
1099			continue;
1100
1101		if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
1102			continue;
1103
1104		memblock_add(ei->addr, ei->size);
1105	}
1106
1107	memblock_analyze();
1108	memblock_dump_all();
1109}
1110
1111void __init memblock_find_dma_reserve(void)
1112{
1113#ifdef CONFIG_X86_64
1114	u64 free_size_pfn;
1115	u64 mem_size_pfn;
 
 
 
 
1116	/*
1117	 * need to find out used area below MAX_DMA_PFN
1118	 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1119	 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1120	 */
1121	mem_size_pfn = memblock_x86_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1122	free_size_pfn = memblock_x86_free_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
1123	set_dma_reserve(mem_size_pfn - free_size_pfn);
 
 
 
 
 
 
 
 
 
 
 
1124#endif
1125}