mm/bootmem.c

   1 /*
   2  *  bootmem - A boot-time physical memory allocator and configurator
   3  *
   4  *  Copyright (C) 1999 Ingo Molnar
   5  *                1999 Kanoj Sarcar, SGI
   6  *                2008 Johannes Weiner
   7  *
   8  * Access to this subsystem has to be serialized externally (which is true
   9  * for the boot process anyway).
  10  */
  11 #include <linux/init.h>
  12 #include <linux/pfn.h>
  13 #include <linux/slab.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/module.h>
  16 #include <linux/kmemleak.h>
  17 #include <linux/range.h>
  18 #include <linux/memblock.h>
  19
  20 #include <asm/bug.h>
  21 #include <asm/io.h>
  22 #include <asm/processor.h>
  23
  24 #include "internal.h"
  25
  26 #ifndef CONFIG_NEED_MULTIPLE_NODES
  27 struct pglist_data __refdata contig_page_data = {
  28         .bdata = &bootmem_node_data[0]
  29 };
  30 EXPORT_SYMBOL(contig_page_data);
  31 #endif
  32
  33 unsigned long max_low_pfn;
  34 unsigned long min_low_pfn;
  35 unsigned long max_pfn;
  36
  37 bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;
  38
  39 static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);
  40
  41 static int bootmem_debug;
  42
  43 static int __init bootmem_debug_setup(char *buf)
  44 {
  45         bootmem_debug = 1;
  46         return 0;
  47 }
  48 early_param("bootmem_debug", bootmem_debug_setup);
  49
  50 #define bdebug(fmt, args...) ({                         \
  51         if (unlikely(bootmem_debug))                    \
  52                 printk(KERN_INFO                        \
  53                         "bootmem::%s " fmt,             \
  54                         __func__, ## args);             \
  55 })
  56
  57 static unsigned long __init bootmap_bytes(unsigned long pages)
  58 {
  59         unsigned long bytes = (pages + 7) / 8;
  60
  61         return ALIGN(bytes, sizeof(long));
  62 }
  63
  64 /**
  65  * bootmem_bootmap_pages - calculate bitmap size in pages
  66  * @pages: number of pages the bitmap has to represent
  67  */
  68 unsigned long __init bootmem_bootmap_pages(unsigned long pages)
  69 {
  70         unsigned long bytes = bootmap_bytes(pages);
  71
  72         return PAGE_ALIGN(bytes) >> PAGE_SHIFT;
  73 }
  74
  75 /*
  76  * link bdata in order
  77  */
  78 static void __init link_bootmem(bootmem_data_t *bdata)
  79 {
  80         struct list_head *iter;
  81
  82         list_for_each(iter, &bdata_list) {
  83                 bootmem_data_t *ent;
  84
  85                 ent = list_entry(iter, bootmem_data_t, list);
  86                 if (bdata->node_min_pfn < ent->node_min_pfn)
  87                         break;
  88         }
  89         list_add_tail(&bdata->list, iter);
  90 }
  91
  92 /*
  93  * Called once to set up the allocator itself.
  94  */
  95 static unsigned long __init init_bootmem_core(bootmem_data_t *bdata,
  96         unsigned long mapstart, unsigned long start, unsigned long end)
  97 {
  98         unsigned long mapsize;
  99
 100         mminit_validate_memmodel_limits(&start, &end);
 101         bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
 102         bdata->node_min_pfn = start;
 103         bdata->node_low_pfn = end;
 104         link_bootmem(bdata);
 105
 106         /*
 107          * Initially all pages are reserved - setup_arch() has to
 108          * register free RAM areas explicitly.
 109          */
 110         mapsize = bootmap_bytes(end - start);
 111         memset(bdata->node_bootmem_map, 0xff, mapsize);
 112
 113         bdebug("nid=%td start=%lx map=%lx end=%lx mapsize=%lx\n",
 114                 bdata - bootmem_node_data, start, mapstart, end, mapsize);
 115
 116         return mapsize;
 117 }
 118
 119 /**
 120  * init_bootmem_node - register a node as boot memory
 121  * @pgdat: node to register
 122  * @freepfn: pfn where the bitmap for this node is to be placed
 123  * @startpfn: first pfn on the node
 124  * @endpfn: first pfn after the node
 125  *
 126  * Returns the number of bytes needed to hold the bitmap for this node.
 127  */
 128 unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
 129                                 unsigned long startpfn, unsigned long endpfn)
 130 {
 131         return init_bootmem_core(pgdat->bdata, freepfn, startpfn, endpfn);
 132 }
 133
 134 /**
 135  * init_bootmem - register boot memory
 136  * @start: pfn where the bitmap is to be placed
 137  * @pages: number of available physical pages
 138  *
 139  * Returns the number of bytes needed to hold the bitmap.
 140  */
 141 unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
 142 {
 143         max_low_pfn = pages;
 144         min_low_pfn = start;
 145         return init_bootmem_core(NODE_DATA(0)->bdata, start, 0, pages);
 146 }
 147
 148 /*
 149  * free_bootmem_late - free bootmem pages directly to page allocator
 150  * @addr: starting address of the range
 151  * @size: size of the range in bytes
 152  *
 153  * This is only useful when the bootmem allocator has already been torn
 154  * down, but we are still initializing the system.  Pages are given directly
 155  * to the page allocator, no bootmem metadata is updated because it is gone.
 156  */
 157 void __init free_bootmem_late(unsigned long addr, unsigned long size)
 158 {
 159         unsigned long cursor, end;
 160
 161         kmemleak_free_part(__va(addr), size);
 162
 163         cursor = PFN_UP(addr);
 164         end = PFN_DOWN(addr + size);
 165
 166         for (; cursor < end; cursor++) {
 167                 __free_pages_bootmem(pfn_to_page(cursor), 0);
 168                 totalram_pages++;
 169         }
 170 }
 171
 172 static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 173 {
 174         int aligned;
 175         struct page *page;
 176         unsigned long start, end, pages, count = 0;
 177
 178         if (!bdata->node_bootmem_map)
 179                 return 0;
 180
 181         start = bdata->node_min_pfn;
 182         end = bdata->node_low_pfn;
 183
 184         /*
 185          * If the start is aligned to the machines wordsize, we might
 186          * be able to free pages in bulks of that order.
 187          */
 188         aligned = !(start & (BITS_PER_LONG - 1));
 189
 190         bdebug("nid=%td start=%lx end=%lx aligned=%d\n",
 191                 bdata - bootmem_node_data, start, end, aligned);
 192
 193         while (start < end) {
 194                 unsigned long *map, idx, vec;
 195
 196                 map = bdata->node_bootmem_map;
 197                 idx = start - bdata->node_min_pfn;
 198                 vec = ~map[idx / BITS_PER_LONG];
 199
 200                 if (aligned && vec == ~0UL && start + BITS_PER_LONG < end) {
 201                         int order = ilog2(BITS_PER_LONG);
 202
 203                         __free_pages_bootmem(pfn_to_page(start), order);
 204                         count += BITS_PER_LONG;
 205                 } else {
 206                         unsigned long off = 0;
 207
 208                         while (vec && off < BITS_PER_LONG) {
 209                                 if (vec & 1) {
 210                                         page = pfn_to_page(start + off);
 211                                         __free_pages_bootmem(page, 0);
 212                                         count++;
 213                                 }
 214                                 vec >>= 1;
 215                                 off++;
 216                         }
 217                 }
 218                 start += BITS_PER_LONG;
 219         }
 220
 221         page = virt_to_page(bdata->node_bootmem_map);
 222         pages = bdata->node_low_pfn - bdata->node_min_pfn;
 223         pages = bootmem_bootmap_pages(pages);
 224         count += pages;
 225         while (pages--)
 226                 __free_pages_bootmem(page++, 0);
 227
 228         bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
 229
 230         return count;
 231 }
 232
 233 /**
 234  * free_all_bootmem_node - release a node's free pages to the buddy allocator
 235  * @pgdat: node to be released
 236  *
 237  * Returns the number of pages actually released.
 238  */
 239 unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 240 {
 241         register_page_bootmem_info_node(pgdat);
 242         return free_all_bootmem_core(pgdat->bdata);
 243 }
 244
 245 /**
 246  * free_all_bootmem - release free pages to the buddy allocator
 247  *
 248  * Returns the number of pages actually released.
 249  */
 250 unsigned long __init free_all_bootmem(void)
 251 {
 252         unsigned long total_pages = 0;
 253         bootmem_data_t *bdata;
 254
 255         list_for_each_entry(bdata, &bdata_list, list)
 256                 total_pages += free_all_bootmem_core(bdata);
 257
 258         return total_pages;
 259 }
 260
 261 static void __init __free(bootmem_data_t *bdata,
 262                         unsigned long sidx, unsigned long eidx)
 263 {
 264         unsigned long idx;
 265
 266         bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
 267                 sidx + bdata->node_min_pfn,
 268                 eidx + bdata->node_min_pfn);
 269
 270         if (bdata->hint_idx > sidx)
 271                 bdata->hint_idx = sidx;
 272
 273         for (idx = sidx; idx < eidx; idx++)
 274                 if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
 275                         BUG();
 276 }
 277
 278 static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
 279                         unsigned long eidx, int flags)
 280 {
 281         unsigned long idx;
 282         int exclusive = flags & BOOTMEM_EXCLUSIVE;
 283
 284         bdebug("nid=%td start=%lx end=%lx flags=%x\n",
 285                 bdata - bootmem_node_data,
 286                 sidx + bdata->node_min_pfn,
 287                 eidx + bdata->node_min_pfn,
 288                 flags);
 289
 290         for (idx = sidx; idx < eidx; idx++)
 291                 if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
 292                         if (exclusive) {
 293                                 __free(bdata, sidx, idx);
 294                                 return -EBUSY;
 295                         }
 296                         bdebug("silent double reserve of PFN %lx\n",
 297                                 idx + bdata->node_min_pfn);
 298                 }
 299         return 0;
 300 }
 301
 302 static int __init mark_bootmem_node(bootmem_data_t *bdata,
 303                                 unsigned long start, unsigned long end,
 304                                 int reserve, int flags)
 305 {
 306         unsigned long sidx, eidx;
 307
 308         bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
 309                 bdata - bootmem_node_data, start, end, reserve, flags);
 310
 311         BUG_ON(start < bdata->node_min_pfn);
 312         BUG_ON(end > bdata->node_low_pfn);
 313
 314         sidx = start - bdata->node_min_pfn;
 315         eidx = end - bdata->node_min_pfn;
 316
 317         if (reserve)
 318                 return __reserve(bdata, sidx, eidx, flags);
 319         else
 320                 __free(bdata, sidx, eidx);
 321         return 0;
 322 }
 323
 324 static int __init mark_bootmem(unsigned long start, unsigned long end,
 325                                 int reserve, int flags)
 326 {
 327         unsigned long pos;
 328         bootmem_data_t *bdata;
 329
 330         pos = start;
 331         list_for_each_entry(bdata, &bdata_list, list) {
 332                 int err;
 333                 unsigned long max;
 334
 335                 if (pos < bdata->node_min_pfn ||
 336                     pos >= bdata->node_low_pfn) {
 337                         BUG_ON(pos != start);
 338                         continue;
 339                 }
 340
 341                 max = min(bdata->node_low_pfn, end);
 342
 343                 err = mark_bootmem_node(bdata, pos, max, reserve, flags);
 344                 if (reserve && err) {
 345                         mark_bootmem(start, pos, 0, 0);
 346                         return err;
 347                 }
 348
 349                 if (max == end)
 350                         return 0;
 351                 pos = bdata->node_low_pfn;
 352         }
 353         BUG();
 354 }
 355
 356 /**
 357  * free_bootmem_node - mark a page range as usable
 358  * @pgdat: node the range resides on
 359  * @physaddr: starting address of the range
 360  * @size: size of the range in bytes
 361  *
 362  * Partial pages will be considered reserved and left as they are.
 363  *
 364  * The range must reside completely on the specified node.
 365  */
 366 void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
 367                               unsigned long size)
 368 {
 369         unsigned long start, end;
 370
 371         kmemleak_free_part(__va(physaddr), size);
 372
 373         start = PFN_UP(physaddr);
 374         end = PFN_DOWN(physaddr + size);
 375
 376         mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
 377 }
 378
 379 /**
 380  * free_bootmem - mark a page range as usable
 381  * @addr: starting address of the range
 382  * @size: size of the range in bytes
 383  *
 384  * Partial pages will be considered reserved and left as they are.
 385  *
 386  * The range must be contiguous but may span node boundaries.
 387  */
 388 void __init free_bootmem(unsigned long addr, unsigned long size)
 389 {
 390         unsigned long start, end;
 391
 392         kmemleak_free_part(__va(addr), size);
 393
 394         start = PFN_UP(addr);
 395         end = PFN_DOWN(addr + size);
 396
 397         mark_bootmem(start, end, 0, 0);
 398 }
 399
 400 /**
 401  * reserve_bootmem_node - mark a page range as reserved
 402  * @pgdat: node the range resides on
 403  * @physaddr: starting address of the range
 404  * @size: size of the range in bytes
 405  * @flags: reservation flags (see linux/bootmem.h)
 406  *
 407  * Partial pages will be reserved.
 408  *
 409  * The range must reside completely on the specified node.
 410  */
 411 int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
 412                                  unsigned long size, int flags)
 413 {
 414         unsigned long start, end;
 415
 416         start = PFN_DOWN(physaddr);
 417         end = PFN_UP(physaddr + size);
 418
 419         return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
 420 }
 421
 422 /**
 423  * reserve_bootmem - mark a page range as usable
 424  * @addr: starting address of the range
 425  * @size: size of the range in bytes
 426  * @flags: reservation flags (see linux/bootmem.h)
 427  *
 428  * Partial pages will be reserved.
 429  *
 430  * The range must be contiguous but may span node boundaries.
 431  */
 432 int __init reserve_bootmem(unsigned long addr, unsigned long size,
 433                             int flags)
 434 {
 435         unsigned long start, end;
 436
 437         start = PFN_DOWN(addr);
 438         end = PFN_UP(addr + size);
 439
 440         return mark_bootmem(start, end, 1, flags);
 441 }
 442
 443 int __weak __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
 444                                    int flags)
 445 {
 446         return reserve_bootmem(phys, len, flags);
 447 }
 448
 449 static unsigned long __init align_idx(struct bootmem_data *bdata,
 450                                       unsigned long idx, unsigned long step)
 451 {
 452         unsigned long base = bdata->node_min_pfn;
 453
 454         /*
 455          * Align the index with respect to the node start so that the
 456          * combination of both satisfies the requested alignment.
 457          */
 458
 459         return ALIGN(base + idx, step) - base;
 460 }
 461
 462 static unsigned long __init align_off(struct bootmem_data *bdata,
 463                                       unsigned long off, unsigned long align)
 464 {
 465         unsigned long base = PFN_PHYS(bdata->node_min_pfn);
 466
 467         /* Same as align_idx for byte offsets */
 468
 469         return ALIGN(base + off, align) - base;
 470 }
 471
 472 static void * __init alloc_bootmem_core(struct bootmem_data *bdata,
 473                                         unsigned long size, unsigned long align,
 474                                         unsigned long goal, unsigned long limit)
 475 {
 476         unsigned long fallback = 0;
 477         unsigned long min, max, start, sidx, midx, step;
 478
 479         bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
 480                 bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
 481                 align, goal, limit);
 482
 483         BUG_ON(!size);
 484         BUG_ON(align & (align - 1));
 485         BUG_ON(limit && goal + size > limit);
 486
 487         if (!bdata->node_bootmem_map)
 488                 return NULL;
 489
 490         min = bdata->node_min_pfn;
 491         max = bdata->node_low_pfn;
 492
 493         goal >>= PAGE_SHIFT;
 494         limit >>= PAGE_SHIFT;
 495
 496         if (limit && max > limit)
 497                 max = limit;
 498         if (max <= min)
 499                 return NULL;
 500
 501         step = max(align >> PAGE_SHIFT, 1UL);
 502
 503         if (goal && min < goal && goal < max)
 504                 start = ALIGN(goal, step);
 505         else
 506                 start = ALIGN(min, step);
 507
 508         sidx = start - bdata->node_min_pfn;
 509         midx = max - bdata->node_min_pfn;
 510
 511         if (bdata->hint_idx > sidx) {
 512                 /*
 513                  * Handle the valid case of sidx being zero and still
 514                  * catch the fallback below.
 515                  */
 516                 fallback = sidx + 1;
 517                 sidx = align_idx(bdata, bdata->hint_idx, step);
 518         }
 519
 520         while (1) {
 521                 int merge;
 522                 void *region;
 523                 unsigned long eidx, i, start_off, end_off;
 524 find_block:
 525                 sidx = find_next_zero_bit(bdata->node_bootmem_map, midx, sidx);
 526                 sidx = align_idx(bdata, sidx, step);
 527                 eidx = sidx + PFN_UP(size);
 528
 529                 if (sidx >= midx || eidx > midx)
 530                         break;
 531
 532                 for (i = sidx; i < eidx; i++)
 533                         if (test_bit(i, bdata->node_bootmem_map)) {
 534                                 sidx = align_idx(bdata, i, step);
 535                                 if (sidx == i)
 536                                         sidx += step;
 537                                 goto find_block;
 538                         }
 539
 540                 if (bdata->last_end_off & (PAGE_SIZE - 1) &&
 541                                 PFN_DOWN(bdata->last_end_off) + 1 == sidx)
 542                         start_off = align_off(bdata, bdata->last_end_off, align);
 543                 else
 544                         start_off = PFN_PHYS(sidx);
 545
 546                 merge = PFN_DOWN(start_off) < sidx;
 547                 end_off = start_off + size;
 548
 549                 bdata->last_end_off = end_off;
 550                 bdata->hint_idx = PFN_UP(end_off);
 551
 552                 /*
 553                  * Reserve the area now:
 554                  */
 555                 if (__reserve(bdata, PFN_DOWN(start_off) + merge,
 556                                 PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
 557                         BUG();
 558
 559                 region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
 560                                 start_off);
 561                 memset(region, 0, size);
 562                 /*
 563                  * The min_count is set to 0 so that bootmem allocated blocks
 564                  * are never reported as leaks.
 565                  */
 566                 kmemleak_alloc(region, size, 0, 0);
 567                 return region;
 568         }
 569
 570         if (fallback) {
 571                 sidx = align_idx(bdata, fallback - 1, step);
 572                 fallback = 0;
 573                 goto find_block;
 574         }
 575
 576         return NULL;
 577 }
 578
 579 static void * __init alloc_arch_preferred_bootmem(bootmem_data_t *bdata,
 580                                         unsigned long size, unsigned long align,
 581                                         unsigned long goal, unsigned long limit)
 582 {
 583         if (WARN_ON_ONCE(slab_is_available()))
 584                 return kzalloc(size, GFP_NOWAIT);
 585
 586 #ifdef CONFIG_HAVE_ARCH_BOOTMEM
 587         {
 588                 bootmem_data_t *p_bdata;
 589
 590                 p_bdata = bootmem_arch_preferred_node(bdata, size, align,
 591                                                         goal, limit);
 592                 if (p_bdata)
 593                         return alloc_bootmem_core(p_bdata, size, align,
 594                                                         goal, limit);
 595         }
 596 #endif
 597         return NULL;
 598 }
 599
 600 static void * __init ___alloc_bootmem_nopanic(unsigned long size,
 601                                         unsigned long align,
 602                                         unsigned long goal,
 603                                         unsigned long limit)
 604 {
 605         bootmem_data_t *bdata;
 606         void *region;
 607
 608 restart:
 609         region = alloc_arch_preferred_bootmem(NULL, size, align, goal, limit);
 610         if (region)
 611                 return region;
 612
 613         list_for_each_entry(bdata, &bdata_list, list) {
 614                 if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
 615                         continue;
 616                 if (limit && bdata->node_min_pfn >= PFN_DOWN(limit))
 617                         break;
 618
 619                 region = alloc_bootmem_core(bdata, size, align, goal, limit);
 620                 if (region)
 621                         return region;
 622         }
 623
 624         if (goal) {
 625                 goal = 0;
 626                 goto restart;
 627         }
 628
 629         return NULL;
 630 }
 631
 632 /**
 633  * __alloc_bootmem_nopanic - allocate boot memory without panicking
 634  * @size: size of the request in bytes
 635  * @align: alignment of the region
 636  * @goal: preferred starting address of the region
 637  *
 638  * The goal is dropped if it can not be satisfied and the allocation will
 639  * fall back to memory below @goal.
 640  *
 641  * Allocation may happen on any node in the system.
 642  *
 643  * Returns NULL on failure.
 644  */
 645 void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
 646                                         unsigned long goal)
 647 {
 648         unsigned long limit = 0;
 649
 650         return ___alloc_bootmem_nopanic(size, align, goal, limit);
 651 }
 652
 653 static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
 654                                         unsigned long goal, unsigned long limit)
 655 {
 656         void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);
 657
 658         if (mem)
 659                 return mem;
 660         /*
 661          * Whoops, we cannot satisfy the allocation request.
 662          */
 663         printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size);
 664         panic("Out of memory");
 665         return NULL;
 666 }
 667
 668 /**
 669  * __alloc_bootmem - allocate boot memory
 670  * @size: size of the request in bytes
 671  * @align: alignment of the region
 672  * @goal: preferred starting address of the region
 673  *
 674  * The goal is dropped if it can not be satisfied and the allocation will
 675  * fall back to memory below @goal.
 676  *
 677  * Allocation may happen on any node in the system.
 678  *
 679  * The function panics if the request can not be satisfied.
 680  */
 681 void * __init __alloc_bootmem(unsigned long size, unsigned long align,
 682                               unsigned long goal)
 683 {
 684         unsigned long limit = 0;
 685
 686         return ___alloc_bootmem(size, align, goal, limit);
 687 }
 688
 689 static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
 690                                 unsigned long size, unsigned long align,
 691                                 unsigned long goal, unsigned long limit)
 692 {
 693         void *ptr;
 694
 695         ptr = alloc_arch_preferred_bootmem(bdata, size, align, goal, limit);
 696         if (ptr)
 697                 return ptr;
 698
 699         ptr = alloc_bootmem_core(bdata, size, align, goal, limit);
 700         if (ptr)
 701                 return ptr;
 702
 703         return ___alloc_bootmem(size, align, goal, limit);
 704 }
 705
 706 /**
 707  * __alloc_bootmem_node - allocate boot memory from a specific node
 708  * @pgdat: node to allocate from
 709  * @size: size of the request in bytes
 710  * @align: alignment of the region
 711  * @goal: preferred starting address of the region
 712  *
 713  * The goal is dropped if it can not be satisfied and the allocation will
 714  * fall back to memory below @goal.
 715  *
 716  * Allocation may fall back to any node in the system if the specified node
 717  * can not hold the requested memory.
 718  *
 719  * The function panics if the request can not be satisfied.
 720  */
 721 void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
 722                                    unsigned long align, unsigned long goal)
 723 {
 724         if (WARN_ON_ONCE(slab_is_available()))
 725                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 726
 727         return  ___alloc_bootmem_node(pgdat->bdata, size, align, goal, 0);
 728 }
 729
 730 void * __init __alloc_bootmem_node_high(pg_data_t *pgdat, unsigned long size,
 731                                    unsigned long align, unsigned long goal)
 732 {
 733 #ifdef MAX_DMA32_PFN
 734         unsigned long end_pfn;
 735
 736         if (WARN_ON_ONCE(slab_is_available()))
 737                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 738
 739         /* update goal according ...MAX_DMA32_PFN */
 740         end_pfn = pgdat->node_start_pfn + pgdat->node_spanned_pages;
 741
 742         if (end_pfn > MAX_DMA32_PFN + (128 >> (20 - PAGE_SHIFT)) &&
 743             (goal >> PAGE_SHIFT) < MAX_DMA32_PFN) {
 744                 void *ptr;
 745                 unsigned long new_goal;
 746
 747                 new_goal = MAX_DMA32_PFN << PAGE_SHIFT;
 748                 ptr = alloc_bootmem_core(pgdat->bdata, size, align,
 749                                                  new_goal, 0);
 750                 if (ptr)
 751                         return ptr;
 752         }
 753 #endif
 754
 755         return __alloc_bootmem_node(pgdat, size, align, goal);
 756
 757 }
 758
 759 #ifdef CONFIG_SPARSEMEM
 760 /**
 761  * alloc_bootmem_section - allocate boot memory from a specific section
 762  * @size: size of the request in bytes
 763  * @section_nr: sparse map section to allocate from
 764  *
 765  * Return NULL on failure.
 766  */
 767 void * __init alloc_bootmem_section(unsigned long size,
 768                                     unsigned long section_nr)
 769 {
 770         bootmem_data_t *bdata;
 771         unsigned long pfn, goal;
 772
 773         pfn = section_nr_to_pfn(section_nr);
 774         goal = pfn << PAGE_SHIFT;
 775         bdata = &bootmem_node_data[early_pfn_to_nid(pfn)];
 776
 777         return alloc_bootmem_core(bdata, size, SMP_CACHE_BYTES, goal, 0);
 778 }
 779 #endif
 780
 781 void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
 782                                    unsigned long align, unsigned long goal)
 783 {
 784         void *ptr;
 785
 786         if (WARN_ON_ONCE(slab_is_available()))
 787                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 788
 789         ptr = alloc_arch_preferred_bootmem(pgdat->bdata, size, align, goal, 0);
 790         if (ptr)
 791                 return ptr;
 792
 793         ptr = alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
 794         if (ptr)
 795                 return ptr;
 796
 797         return __alloc_bootmem_nopanic(size, align, goal);
 798 }
 799
 800 #ifndef ARCH_LOW_ADDRESS_LIMIT
 801 #define ARCH_LOW_ADDRESS_LIMIT  0xffffffffUL
 802 #endif
 803
 804 /**
 805  * __alloc_bootmem_low - allocate low boot memory
 806  * @size: size of the request in bytes
 807  * @align: alignment of the region
 808  * @goal: preferred starting address of the region
 809  *
 810  * The goal is dropped if it can not be satisfied and the allocation will
 811  * fall back to memory below @goal.
 812  *
 813  * Allocation may happen on any node in the system.
 814  *
 815  * The function panics if the request can not be satisfied.
 816  */
 817 void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
 818                                   unsigned long goal)
 819 {
 820         return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
 821 }
 822
 823 /**
 824  * __alloc_bootmem_low_node - allocate low boot memory from a specific node
 825  * @pgdat: node to allocate from
 826  * @size: size of the request in bytes
 827  * @align: alignment of the region
 828  * @goal: preferred starting address of the region
 829  *
 830  * The goal is dropped if it can not be satisfied and the allocation will
 831  * fall back to memory below @goal.
 832  *
 833  * Allocation may fall back to any node in the system if the specified node
 834  * can not hold the requested memory.
 835  *
 836  * The function panics if the request can not be satisfied.
 837  */
 838 void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
 839                                        unsigned long align, unsigned long goal)
 840 {
 841         if (WARN_ON_ONCE(slab_is_available()))
 842                 return kzalloc_node(size, GFP_NOWAIT, pgdat->node_id);
 843
 844         return ___alloc_bootmem_node(pgdat->bdata, size, align,
 845                                 goal, ARCH_LOW_ADDRESS_LIMIT);
 846 }