1#include <linux/kernel.h> 2#include <linux/types.h> 3#include <linux/init.h> 4#include <linux/bootmem.h> 5#include <linux/ioport.h> 6#include <linux/string.h> 7#include <linux/kexec.h> 8#include <linux/module.h> 9#include <linux/mm.h> 10#include <linux/efi.h> 11#include <linux/pfn.h> 12#include <linux/uaccess.h> 13 14#include <asm/pgtable.h> 15#include <asm/page.h> 16#include <asm/e820.h> 17#include <asm/setup.h> 18 19#ifdef CONFIG_EFI 20int efi_enabled = 0; 21EXPORT_SYMBOL(efi_enabled); 22#endif 23 24struct e820map e820; 25struct change_member { 26 struct e820entry *pbios; /* pointer to original bios entry */ 27 unsigned long long addr; /* address for this change point */ 28}; 29static struct change_member change_point_list[2*E820MAX] __initdata; 30static struct change_member *change_point[2*E820MAX] __initdata; 31static struct e820entry *overlap_list[E820MAX] __initdata; 32static struct e820entry new_bios[E820MAX] __initdata; 33/* For PCI or other memory-mapped resources */ 34unsigned long pci_mem_start = 0x10000000; 35#ifdef CONFIG_PCI 36EXPORT_SYMBOL(pci_mem_start); 37#endif 38extern int user_defined_memmap; 39struct resource data_resource = { 40 .name = "Kernel data", 41 .start = 0, 42 .end = 0, 43 .flags = IORESOURCE_BUSY | IORESOURCE_MEM 44}; 45 46struct resource code_resource = { 47 .name = "Kernel code", 48 .start = 0, 49 .end = 0, 50 .flags = IORESOURCE_BUSY | IORESOURCE_MEM 51}; 52 53static struct resource system_rom_resource = { 54 .name = "System ROM", 55 .start = 0xf0000, 56 .end = 0xfffff, 57 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 58}; 59 60static struct resource extension_rom_resource = { 61 .name = "Extension ROM", 62 .start = 0xe0000, 63 .end = 0xeffff, 64 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 65}; 66 67static struct resource adapter_rom_resources[] = { { 68 .name = "Adapter ROM", 69 .start = 0xc8000, 70 .end = 0, 71 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 72}, { 73 .name = "Adapter ROM", 74 .start = 0, 75 .end = 0, 76 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 77}, { 78 .name = "Adapter ROM", 79 .start = 0, 80 .end = 0, 81 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 82}, { 83 .name = "Adapter ROM", 84 .start = 0, 85 .end = 0, 86 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 87}, { 88 .name = "Adapter ROM", 89 .start = 0, 90 .end = 0, 91 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 92}, { 93 .name = "Adapter ROM", 94 .start = 0, 95 .end = 0, 96 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 97} }; 98 99static struct resource video_rom_resource = { 100 .name = "Video ROM", 101 .start = 0xc0000, 102 .end = 0xc7fff, 103 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM 104}; 105 106static struct resource video_ram_resource = { 107 .name = "Video RAM area", 108 .start = 0xa0000, 109 .end = 0xbffff, 110 .flags = IORESOURCE_BUSY | IORESOURCE_MEM 111}; 112 113static struct resource standard_io_resources[] = { { 114 .name = "dma1", 115 .start = 0x0000, 116 .end = 0x001f, 117 .flags = IORESOURCE_BUSY | IORESOURCE_IO 118}, { 119 .name = "pic1", 120 .start = 0x0020, 121 .end = 0x0021, 122 .flags = IORESOURCE_BUSY | IORESOURCE_IO 123}, { 124 .name = "timer0", 125 .start = 0x0040, 126 .end = 0x0043, 127 .flags = IORESOURCE_BUSY | IORESOURCE_IO 128}, { 129 .name = "timer1", 130 .start = 0x0050, 131 .end = 0x0053, 132 .flags = IORESOURCE_BUSY | IORESOURCE_IO 133}, { 134 .name = "keyboard", 135 .start = 0x0060, 136 .end = 0x006f, 137 .flags = IORESOURCE_BUSY | IORESOURCE_IO 138}, { 139 .name = "dma page reg", 140 .start = 0x0080, 141 .end = 0x008f, 142 .flags = IORESOURCE_BUSY | IORESOURCE_IO 143}, { 144 .name = "pic2", 145 .start = 0x00a0, 146 .end = 0x00a1, 147 .flags = IORESOURCE_BUSY | IORESOURCE_IO 148}, { 149 .name = "dma2", 150 .start = 0x00c0, 151 .end = 0x00df, 152 .flags = IORESOURCE_BUSY | IORESOURCE_IO 153}, { 154 .name = "fpu", 155 .start = 0x00f0, 156 .end = 0x00ff, 157 .flags = IORESOURCE_BUSY | IORESOURCE_IO 158} }; 159 160#define ROMSIGNATURE 0xaa55 161 162static int __init romsignature(const unsigned char *rom) 163{ 164 const unsigned short * const ptr = (const unsigned short *)rom; 165 unsigned short sig; 166 167 return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE; 168} 169 170static int __init romchecksum(const unsigned char *rom, unsigned long length) 171{ 172 unsigned char sum, c; 173 174 for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--) 175 sum += c; 176 return !length && !sum; 177} 178 179static void __init probe_roms(void) 180{ 181 const unsigned char *rom; 182 unsigned long start, length, upper; 183 unsigned char c; 184 int i; 185 186 /* video rom */ 187 upper = adapter_rom_resources[0].start; 188 for (start = video_rom_resource.start; start < upper; start += 2048) { 189 rom = isa_bus_to_virt(start); 190 if (!romsignature(rom)) 191 continue; 192 193 video_rom_resource.start = start; 194 195 if (probe_kernel_address(rom + 2, c) != 0) 196 continue; 197 198 /* 0 < length <= 0x7f * 512, historically */ 199 length = c * 512; 200 201 /* if checksum okay, trust length byte */ 202 if (length && romchecksum(rom, length)) 203 video_rom_resource.end = start + length - 1; 204 205 request_resource(&iomem_resource, &video_rom_resource); 206 break; 207 } 208 209 start = (video_rom_resource.end + 1 + 2047) & ~2047UL; 210 if (start < upper) 211 start = upper; 212 213 /* system rom */ 214 request_resource(&iomem_resource, &system_rom_resource); 215 upper = system_rom_resource.start; 216 217 /* check for extension rom (ignore length byte!) */ 218 rom = isa_bus_to_virt(extension_rom_resource.start); 219 if (romsignature(rom)) { 220 length = extension_rom_resource.end - extension_rom_resource.start + 1; 221 if (romchecksum(rom, length)) { 222 request_resource(&iomem_resource, &extension_rom_resource); 223 upper = extension_rom_resource.start; 224 } 225 } 226 227 /* check for adapter roms on 2k boundaries */ 228 for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) { 229 rom = isa_bus_to_virt(start); 230 if (!romsignature(rom)) 231 continue; 232 233 if (probe_kernel_address(rom + 2, c) != 0) 234 continue; 235 236 /* 0 < length <= 0x7f * 512, historically */ 237 length = c * 512; 238 239 /* but accept any length that fits if checksum okay */ 240 if (!length || start + length > upper || !romchecksum(rom, length)) 241 continue; 242 243 adapter_rom_resources[i].start = start; 244 adapter_rom_resources[i].end = start + length - 1; 245 request_resource(&iomem_resource, &adapter_rom_resources[i]); 246 247 start = adapter_rom_resources[i++].end & ~2047UL; 248 } 249} 250 251/* 252 * Request address space for all standard RAM and ROM resources 253 * and also for regions reported as reserved by the e820. 254 */ 255static void __init 256legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource) 257{ 258 int i; 259 260 probe_roms(); 261 for (i = 0; i < e820.nr_map; i++) { 262 struct resource *res; 263#ifndef CONFIG_RESOURCES_64BIT 264 if (e820.map[i].addr + e820.map[i].size > 0x100000000ULL) 265 continue; 266#endif 267 res = kzalloc(sizeof(struct resource), GFP_ATOMIC); 268 switch (e820.map[i].type) { 269 case E820_RAM: res->name = "System RAM"; break; 270 case E820_ACPI: res->name = "ACPI Tables"; break; 271 case E820_NVS: res->name = "ACPI Non-volatile Storage"; break; 272 default: res->name = "reserved"; 273 } 274 res->start = e820.map[i].addr; 275 res->end = res->start + e820.map[i].size - 1; 276 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; 277 if (request_resource(&iomem_resource, res)) { 278 kfree(res); 279 continue; 280 } 281 if (e820.map[i].type == E820_RAM) { 282 /* 283 * We don't know which RAM region contains kernel data, 284 * so we try it repeatedly and let the resource manager 285 * test it. 286 */ 287 request_resource(res, code_resource); 288 request_resource(res, data_resource); 289#ifdef CONFIG_KEXEC 290 request_resource(res, &crashk_res); 291#endif 292 } 293 } 294} 295 296/* 297 * Request address space for all standard resources 298 * 299 * This is called just before pcibios_init(), which is also a 300 * subsys_initcall, but is linked in later (in arch/i386/pci/common.c). 301 */ 302static int __init request_standard_resources(void) 303{ 304 int i; 305 306 printk("Setting up standard PCI resources\n"); 307 if (efi_enabled) 308 efi_initialize_iomem_resources(&code_resource, &data_resource); 309 else 310 legacy_init_iomem_resources(&code_resource, &data_resource); 311 312 /* EFI systems may still have VGA */ 313 request_resource(&iomem_resource, &video_ram_resource); 314 315 /* request I/O space for devices used on all i[345]86 PCs */ 316 for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++) 317 request_resource(&ioport_resource, &standard_io_resources[i]); 318 return 0; 319} 320 321subsys_initcall(request_standard_resources); 322 323void __init add_memory_region(unsigned long long start, 324 unsigned long long size, int type) 325{ 326 int x; 327 328 if (!efi_enabled) { 329 x = e820.nr_map; 330 331 if (x == E820MAX) { 332 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n"); 333 return; 334 } 335 336 e820.map[x].addr = start; 337 e820.map[x].size = size; 338 e820.map[x].type = type; 339 e820.nr_map++; 340 } 341} /* add_memory_region */ 342 343/* 344 * Sanitize the BIOS e820 map. 345 * 346 * Some e820 responses include overlapping entries. The following 347 * replaces the original e820 map with a new one, removing overlaps. 348 * 349 */ 350int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map) 351{ 352 struct change_member *change_tmp; 353 unsigned long current_type, last_type; 354 unsigned long long last_addr; 355 int chgidx, still_changing; 356 int overlap_entries; 357 int new_bios_entry; 358 int old_nr, new_nr, chg_nr; 359 int i; 360 361 /* 362 Visually we're performing the following (1,2,3,4 = memory types)... 363 364 Sample memory map (w/overlaps): 365 ____22__________________ 366 ______________________4_ 367 ____1111________________ 368 _44_____________________ 369 11111111________________ 370 ____________________33__ 371 ___________44___________ 372 __________33333_________ 373 ______________22________ 374 ___________________2222_ 375 _________111111111______ 376 _____________________11_ 377 _________________4______ 378 379 Sanitized equivalent (no overlap): 380 1_______________________ 381 _44_____________________ 382 ___1____________________ 383 ____22__________________ 384 ______11________________ 385 _________1______________ 386 __________3_____________ 387 ___________44___________ 388 _____________33_________ 389 _______________2________ 390 ________________1_______ 391 _________________4______ 392 ___________________2____ 393 ____________________33__ 394 ______________________4_ 395 */ 396 /* if there's only one memory region, don't bother */ 397 if (*pnr_map < 2) { 398 return -1; 399 } 400 401 old_nr = *pnr_map; 402 403 /* bail out if we find any unreasonable addresses in bios map */ 404 for (i=0; i<old_nr; i++) 405 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) { 406 return -1; 407 } 408 409 /* create pointers for initial change-point information (for sorting) */ 410 for (i=0; i < 2*old_nr; i++) 411 change_point[i] = &change_point_list[i]; 412 413 /* record all known change-points (starting and ending addresses), 414 omitting those that are for empty memory regions */ 415 chgidx = 0; 416 for (i=0; i < old_nr; i++) { 417 if (biosmap[i].size != 0) { 418 change_point[chgidx]->addr = biosmap[i].addr; 419 change_point[chgidx++]->pbios = &biosmap[i]; 420 change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; 421 change_point[chgidx++]->pbios = &biosmap[i]; 422 } 423 } 424 chg_nr = chgidx; /* true number of change-points */ 425 426 /* sort change-point list by memory addresses (low -> high) */ 427 still_changing = 1; 428 while (still_changing) { 429 still_changing = 0; 430 for (i=1; i < chg_nr; i++) { 431 /* if <current_addr> > <last_addr>, swap */ 432 /* or, if current=<start_addr> & last=<end_addr>, swap */ 433 if ((change_point[i]->addr < change_point[i-1]->addr) || 434 ((change_point[i]->addr == change_point[i-1]->addr) && 435 (change_point[i]->addr == change_point[i]->pbios->addr) && 436 (change_point[i-1]->addr != change_point[i-1]->pbios->addr)) 437 ) 438 { 439 change_tmp = change_point[i]; 440 change_point[i] = change_point[i-1]; 441 change_point[i-1] = change_tmp; 442 still_changing=1; 443 } 444 } 445 } 446 447 /* create a new bios memory map, removing overlaps */ 448 overlap_entries=0; /* number of entries in the overlap table */ 449 new_bios_entry=0; /* index for creating new bios map entries */ 450 last_type = 0; /* start with undefined memory type */ 451 last_addr = 0; /* start with 0 as last starting address */ 452 /* loop through change-points, determining affect on the new bios map */ 453 for (chgidx=0; chgidx < chg_nr; chgidx++) 454 { 455 /* keep track of all overlapping bios entries */ 456 if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) 457 { 458 /* add map entry to overlap list (> 1 entry implies an overlap) */ 459 overlap_list[overlap_entries++]=change_point[chgidx]->pbios; 460 } 461 else 462 { 463 /* remove entry from list (order independent, so swap with last) */ 464 for (i=0; i<overlap_entries; i++) 465 { 466 if (overlap_list[i] == change_point[chgidx]->pbios) 467 overlap_list[i] = overlap_list[overlap_entries-1]; 468 } 469 overlap_entries--; 470 } 471 /* if there are overlapping entries, decide which "type" to use */ 472 /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */ 473 current_type = 0; 474 for (i=0; i<overlap_entries; i++) 475 if (overlap_list[i]->type > current_type) 476 current_type = overlap_list[i]->type; 477 /* continue building up new bios map based on this information */ 478 if (current_type != last_type) { 479 if (last_type != 0) { 480 new_bios[new_bios_entry].size = 481 change_point[chgidx]->addr - last_addr; 482 /* move forward only if the new size was non-zero */ 483 if (new_bios[new_bios_entry].size != 0) 484 if (++new_bios_entry >= E820MAX) 485 break; /* no more space left for new bios entries */ 486 } 487 if (current_type != 0) { 488 new_bios[new_bios_entry].addr = change_point[chgidx]->addr; 489 new_bios[new_bios_entry].type = current_type; 490 last_addr=change_point[chgidx]->addr; 491 } 492 last_type = current_type; 493 } 494 } 495 new_nr = new_bios_entry; /* retain count for new bios entries */ 496 497 /* copy new bios mapping into original location */ 498 memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry)); 499 *pnr_map = new_nr; 500 501 return 0; 502} 503 504/* 505 * Copy the BIOS e820 map into a safe place. 506 * 507 * Sanity-check it while we're at it.. 508 * 509 * If we're lucky and live on a modern system, the setup code 510 * will have given us a memory map that we can use to properly 511 * set up memory. If we aren't, we'll fake a memory map. 512 * 513 * We check to see that the memory map contains at least 2 elements 514 * before we'll use it, because the detection code in setup.S may 515 * not be perfect and most every PC known to man has two memory 516 * regions: one from 0 to 640k, and one from 1mb up. (The IBM 517 * thinkpad 560x, for example, does not cooperate with the memory 518 * detection code.) 519 */ 520int __init copy_e820_map(struct e820entry * biosmap, int nr_map) 521{ 522 /* Only one memory region (or negative)? Ignore it */ 523 if (nr_map < 2) 524 return -1; 525 526 do { 527 unsigned long long start = biosmap->addr; 528 unsigned long long size = biosmap->size; 529 unsigned long long end = start + size; 530 unsigned long type = biosmap->type; 531 532 /* Overflow in 64 bits? Ignore the memory map. */ 533 if (start > end) 534 return -1; 535 536 /* 537 * Some BIOSes claim RAM in the 640k - 1M region. 538 * Not right. Fix it up. 539 */ 540 if (type == E820_RAM) { 541 if (start < 0x100000ULL && end > 0xA0000ULL) { 542 if (start < 0xA0000ULL) 543 add_memory_region(start, 0xA0000ULL-start, type); 544 if (end <= 0x100000ULL) 545 continue; 546 start = 0x100000ULL; 547 size = end - start; 548 } 549 } 550 add_memory_region(start, size, type); 551 } while (biosmap++,--nr_map); 552 return 0; 553} 554 555/* 556 * Callback for efi_memory_walk. 557 */ 558static int __init 559efi_find_max_pfn(unsigned long start, unsigned long end, void *arg) 560{ 561 unsigned long *max_pfn = arg, pfn; 562 563 if (start < end) { 564 pfn = PFN_UP(end -1); 565 if (pfn > *max_pfn) 566 *max_pfn = pfn; 567 } 568 return 0; 569} 570 571static int __init 572efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg) 573{ 574 memory_present(0, PFN_UP(start), PFN_DOWN(end)); 575 return 0; 576} 577 578/* 579 * Find the highest page frame number we have available 580 */ 581void __init find_max_pfn(void) 582{ 583 int i; 584 585 max_pfn = 0; 586 if (efi_enabled) { 587 efi_memmap_walk(efi_find_max_pfn, &max_pfn); 588 efi_memmap_walk(efi_memory_present_wrapper, NULL); 589 return; 590 } 591 592 for (i = 0; i < e820.nr_map; i++) { 593 unsigned long start, end; 594 /* RAM? */ 595 if (e820.map[i].type != E820_RAM) 596 continue; 597 start = PFN_UP(e820.map[i].addr); 598 end = PFN_DOWN(e820.map[i].addr + e820.map[i].size); 599 if (start >= end) 600 continue; 601 if (end > max_pfn) 602 max_pfn = end; 603 memory_present(0, start, end); 604 } 605} 606 607/* 608 * Free all available memory for boot time allocation. Used 609 * as a callback function by efi_memory_walk() 610 */ 611 612static int __init 613free_available_memory(unsigned long start, unsigned long end, void *arg) 614{ 615 /* check max_low_pfn */ 616 if (start >= (max_low_pfn << PAGE_SHIFT)) 617 return 0; 618 if (end >= (max_low_pfn << PAGE_SHIFT)) 619 end = max_low_pfn << PAGE_SHIFT; 620 if (start < end) 621 free_bootmem(start, end - start); 622 623 return 0; 624} 625/* 626 * Register fully available low RAM pages with the bootmem allocator. 627 */ 628void __init register_bootmem_low_pages(unsigned long max_low_pfn) 629{ 630 int i; 631 632 if (efi_enabled) { 633 efi_memmap_walk(free_available_memory, NULL); 634 return; 635 } 636 for (i = 0; i < e820.nr_map; i++) { 637 unsigned long curr_pfn, last_pfn, size; 638 /* 639 * Reserve usable low memory 640 */ 641 if (e820.map[i].type != E820_RAM) 642 continue; 643 /* 644 * We are rounding up the start address of usable memory: 645 */ 646 curr_pfn = PFN_UP(e820.map[i].addr); 647 if (curr_pfn >= max_low_pfn) 648 continue; 649 /* 650 * ... and at the end of the usable range downwards: 651 */ 652 last_pfn = PFN_DOWN(e820.map[i].addr + e820.map[i].size); 653 654 if (last_pfn > max_low_pfn) 655 last_pfn = max_low_pfn; 656 657 /* 658 * .. finally, did all the rounding and playing 659 * around just make the area go away? 660 */ 661 if (last_pfn <= curr_pfn) 662 continue; 663 664 size = last_pfn - curr_pfn; 665 free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(size)); 666 } 667} 668 669void __init e820_register_memory(void) 670{ 671 unsigned long gapstart, gapsize, round; 672 unsigned long long last; 673 int i; 674 675 /* 676 * Search for the bigest gap in the low 32 bits of the e820 677 * memory space. 678 */ 679 last = 0x100000000ull; 680 gapstart = 0x10000000; 681 gapsize = 0x400000; 682 i = e820.nr_map; 683 while (--i >= 0) { 684 unsigned long long start = e820.map[i].addr; 685 unsigned long long end = start + e820.map[i].size; 686 687 /* 688 * Since "last" is at most 4GB, we know we'll 689 * fit in 32 bits if this condition is true 690 */ 691 if (last > end) { 692 unsigned long gap = last - end; 693 694 if (gap > gapsize) { 695 gapsize = gap; 696 gapstart = end; 697 } 698 } 699 if (start < last) 700 last = start; 701 } 702 703 /* 704 * See how much we want to round up: start off with 705 * rounding to the next 1MB area. 706 */ 707 round = 0x100000; 708 while ((gapsize >> 4) > round) 709 round += round; 710 /* Fun with two's complement */ 711 pci_mem_start = (gapstart + round) & -round; 712 713 printk("Allocating PCI resources starting at %08lx (gap: %08lx:%08lx)\n", 714 pci_mem_start, gapstart, gapsize); 715} 716 717void __init print_memory_map(char *who) 718{ 719 int i; 720 721 for (i = 0; i < e820.nr_map; i++) { 722 printk(" %s: %016Lx - %016Lx ", who, 723 e820.map[i].addr, 724 e820.map[i].addr + e820.map[i].size); 725 switch (e820.map[i].type) { 726 case E820_RAM: printk("(usable)\n"); 727 break; 728 case E820_RESERVED: 729 printk("(reserved)\n"); 730 break; 731 case E820_ACPI: 732 printk("(ACPI data)\n"); 733 break; 734 case E820_NVS: 735 printk("(ACPI NVS)\n"); 736 break; 737 default: printk("type %lu\n", e820.map[i].type); 738 break; 739 } 740 } 741} 742 743static __init __always_inline void efi_limit_regions(unsigned long long size) 744{ 745 unsigned long long current_addr = 0; 746 efi_memory_desc_t *md, *next_md; 747 void *p, *p1; 748 int i, j; 749 750 j = 0; 751 p1 = memmap.map; 752 for (p = p1, i = 0; p < memmap.map_end; p += memmap.desc_size, i++) { 753 md = p; 754 next_md = p1; 755 current_addr = md->phys_addr + 756 PFN_PHYS(md->num_pages); 757 if (is_available_memory(md)) { 758 if (md->phys_addr >= size) continue; 759 memcpy(next_md, md, memmap.desc_size); 760 if (current_addr >= size) { 761 next_md->num_pages -= 762 PFN_UP(current_addr-size); 763 } 764 p1 += memmap.desc_size; 765 next_md = p1; 766 j++; 767 } else if ((md->attribute & EFI_MEMORY_RUNTIME) == 768 EFI_MEMORY_RUNTIME) { 769 /* In order to make runtime services 770 * available we have to include runtime 771 * memory regions in memory map */ 772 memcpy(next_md, md, memmap.desc_size); 773 p1 += memmap.desc_size; 774 next_md = p1; 775 j++; 776 } 777 } 778 memmap.nr_map = j; 779 memmap.map_end = memmap.map + 780 (memmap.nr_map * memmap.desc_size); 781} 782 783void __init limit_regions(unsigned long long size) 784{ 785 unsigned long long current_addr; 786 int i; 787 788 print_memory_map("limit_regions start"); 789 if (efi_enabled) { 790 efi_limit_regions(size); 791 return; 792 } 793 for (i = 0; i < e820.nr_map; i++) { 794 current_addr = e820.map[i].addr + e820.map[i].size; 795 if (current_addr < size) 796 continue; 797 798 if (e820.map[i].type != E820_RAM) 799 continue; 800 801 if (e820.map[i].addr >= size) { 802 /* 803 * This region starts past the end of the 804 * requested size, skip it completely. 805 */ 806 e820.nr_map = i; 807 } else { 808 e820.nr_map = i + 1; 809 e820.map[i].size -= current_addr - size; 810 } 811 print_memory_map("limit_regions endfor"); 812 return; 813 } 814 print_memory_map("limit_regions endfunc"); 815} 816 817/* 818 * This function checks if any part of the range <start,end> is mapped 819 * with type. 820 */ 821int 822e820_any_mapped(u64 start, u64 end, unsigned type) 823{ 824 int i; 825 for (i = 0; i < e820.nr_map; i++) { 826 const struct e820entry *ei = &e820.map[i]; 827 if (type && ei->type != type) 828 continue; 829 if (ei->addr >= end || ei->addr + ei->size <= start) 830 continue; 831 return 1; 832 } 833 return 0; 834} 835EXPORT_SYMBOL_GPL(e820_any_mapped); 836 837 /* 838 * This function checks if the entire range <start,end> is mapped with type. 839 * 840 * Note: this function only works correct if the e820 table is sorted and 841 * not-overlapping, which is the case 842 */ 843int __init 844e820_all_mapped(unsigned long s, unsigned long e, unsigned type) 845{ 846 u64 start = s; 847 u64 end = e; 848 int i; 849 for (i = 0; i < e820.nr_map; i++) { 850 struct e820entry *ei = &e820.map[i]; 851 if (type && ei->type != type) 852 continue; 853 /* is the region (part) in overlap with the current region ?*/ 854 if (ei->addr >= end || ei->addr + ei->size <= start) 855 continue; 856 /* if the region is at the beginning of <start,end> we move 857 * start to the end of the region since it's ok until there 858 */ 859 if (ei->addr <= start) 860 start = ei->addr + ei->size; 861 /* if start is now at or beyond end, we're done, full 862 * coverage */ 863 if (start >= end) 864 return 1; /* we're done */ 865 } 866 return 0; 867} 868 869static int __init parse_memmap(char *arg) 870{ 871 if (!arg) 872 return -EINVAL; 873 874 if (strcmp(arg, "exactmap") == 0) { 875#ifdef CONFIG_CRASH_DUMP 876 /* If we are doing a crash dump, we 877 * still need to know the real mem 878 * size before original memory map is 879 * reset. 880 */ 881 find_max_pfn(); 882 saved_max_pfn = max_pfn; 883#endif 884 e820.nr_map = 0; 885 user_defined_memmap = 1; 886 } else { 887 /* If the user specifies memory size, we 888 * limit the BIOS-provided memory map to 889 * that size. exactmap can be used to specify 890 * the exact map. mem=number can be used to 891 * trim the existing memory map. 892 */ 893 unsigned long long start_at, mem_size; 894 895 mem_size = memparse(arg, &arg); 896 if (*arg == '@') { 897 start_at = memparse(arg+1, &arg); 898 add_memory_region(start_at, mem_size, E820_RAM); 899 } else if (*arg == '#') { 900 start_at = memparse(arg+1, &arg); 901 add_memory_region(start_at, mem_size, E820_ACPI); 902 } else if (*arg == '$') { 903 start_at = memparse(arg+1, &arg); 904 add_memory_region(start_at, mem_size, E820_RESERVED); 905 } else { 906 limit_regions(mem_size); 907 user_defined_memmap = 1; 908 } 909 } 910 return 0; 911} 912early_param("memmap", parse_memmap); 913