linux/mm/memblock.c
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   1/*
   2 * Procedures for maintaining information about logical memory blocks.
   3 *
   4 * Peter Bergner, IBM Corp.     June 2001.
   5 * Copyright (C) 2001 Peter Bergner.
   6 *
   7 *      This program is free software; you can redistribute it and/or
   8 *      modify it under the terms of the GNU General Public License
   9 *      as published by the Free Software Foundation; either version
  10 *      2 of the License, or (at your option) any later version.
  11 */
  12
  13#include <linux/kernel.h>
  14#include <linux/slab.h>
  15#include <linux/init.h>
  16#include <linux/bitops.h>
  17#include <linux/poison.h>
  18#include <linux/pfn.h>
  19#include <linux/debugfs.h>
  20#include <linux/seq_file.h>
  21#include <linux/memblock.h>
  22
  23static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
  24static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
  25
  26struct memblock memblock __initdata_memblock = {
  27        .memory.regions         = memblock_memory_init_regions,
  28        .memory.cnt             = 1,    /* empty dummy entry */
  29        .memory.max             = INIT_MEMBLOCK_REGIONS,
  30
  31        .reserved.regions       = memblock_reserved_init_regions,
  32        .reserved.cnt           = 1,    /* empty dummy entry */
  33        .reserved.max           = INIT_MEMBLOCK_REGIONS,
  34
  35        .current_limit          = MEMBLOCK_ALLOC_ANYWHERE,
  36};
  37
  38int memblock_debug __initdata_memblock;
  39static int memblock_can_resize __initdata_memblock;
  40static int memblock_memory_in_slab __initdata_memblock = 0;
  41static int memblock_reserved_in_slab __initdata_memblock = 0;
  42
  43/* inline so we don't get a warning when pr_debug is compiled out */
  44static __init_memblock const char *
  45memblock_type_name(struct memblock_type *type)
  46{
  47        if (type == &memblock.memory)
  48                return "memory";
  49        else if (type == &memblock.reserved)
  50                return "reserved";
  51        else
  52                return "unknown";
  53}
  54
  55/* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
  56static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
  57{
  58        return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
  59}
  60
  61/*
  62 * Address comparison utilities
  63 */
  64static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
  65                                       phys_addr_t base2, phys_addr_t size2)
  66{
  67        return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
  68}
  69
  70static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
  71                                        phys_addr_t base, phys_addr_t size)
  72{
  73        unsigned long i;
  74
  75        for (i = 0; i < type->cnt; i++) {
  76                phys_addr_t rgnbase = type->regions[i].base;
  77                phys_addr_t rgnsize = type->regions[i].size;
  78                if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
  79                        break;
  80        }
  81
  82        return (i < type->cnt) ? i : -1;
  83}
  84
  85/**
  86 * memblock_find_in_range_node - find free area in given range and node
  87 * @start: start of candidate range
  88 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
  89 * @size: size of free area to find
  90 * @align: alignment of free area to find
  91 * @nid: nid of the free area to find, %MAX_NUMNODES for any node
  92 *
  93 * Find @size free area aligned to @align in the specified range and node.
  94 *
  95 * RETURNS:
  96 * Found address on success, %0 on failure.
  97 */
  98phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start,
  99                                        phys_addr_t end, phys_addr_t size,
 100                                        phys_addr_t align, int nid)
 101{
 102        phys_addr_t this_start, this_end, cand;
 103        u64 i;
 104
 105        /* pump up @end */
 106        if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
 107                end = memblock.current_limit;
 108
 109        /* avoid allocating the first page */
 110        start = max_t(phys_addr_t, start, PAGE_SIZE);
 111        end = max(start, end);
 112
 113        for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
 114                this_start = clamp(this_start, start, end);
 115                this_end = clamp(this_end, start, end);
 116
 117                if (this_end < size)
 118                        continue;
 119
 120                cand = round_down(this_end - size, align);
 121                if (cand >= this_start)
 122                        return cand;
 123        }
 124        return 0;
 125}
 126
 127/**
 128 * memblock_find_in_range - find free area in given range
 129 * @start: start of candidate range
 130 * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
 131 * @size: size of free area to find
 132 * @align: alignment of free area to find
 133 *
 134 * Find @size free area aligned to @align in the specified range.
 135 *
 136 * RETURNS:
 137 * Found address on success, %0 on failure.
 138 */
 139phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
 140                                        phys_addr_t end, phys_addr_t size,
 141                                        phys_addr_t align)
 142{
 143        return memblock_find_in_range_node(start, end, size, align,
 144                                           MAX_NUMNODES);
 145}
 146
 147static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
 148{
 149        type->total_size -= type->regions[r].size;
 150        memmove(&type->regions[r], &type->regions[r + 1],
 151                (type->cnt - (r + 1)) * sizeof(type->regions[r]));
 152        type->cnt--;
 153
 154        /* Special case for empty arrays */
 155        if (type->cnt == 0) {
 156                WARN_ON(type->total_size != 0);
 157                type->cnt = 1;
 158                type->regions[0].base = 0;
 159                type->regions[0].size = 0;
 160                memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
 161        }
 162}
 163
 164phys_addr_t __init_memblock get_allocated_memblock_reserved_regions_info(
 165                                        phys_addr_t *addr)
 166{
 167        if (memblock.reserved.regions == memblock_reserved_init_regions)
 168                return 0;
 169
 170        *addr = __pa(memblock.reserved.regions);
 171
 172        return PAGE_ALIGN(sizeof(struct memblock_region) *
 173                          memblock.reserved.max);
 174}
 175
 176/**
 177 * memblock_double_array - double the size of the memblock regions array
 178 * @type: memblock type of the regions array being doubled
 179 * @new_area_start: starting address of memory range to avoid overlap with
 180 * @new_area_size: size of memory range to avoid overlap with
 181 *
 182 * Double the size of the @type regions array. If memblock is being used to
 183 * allocate memory for a new reserved regions array and there is a previously
 184 * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
 185 * waiting to be reserved, ensure the memory used by the new array does
 186 * not overlap.
 187 *
 188 * RETURNS:
 189 * 0 on success, -1 on failure.
 190 */
 191static int __init_memblock memblock_double_array(struct memblock_type *type,
 192                                                phys_addr_t new_area_start,
 193                                                phys_addr_t new_area_size)
 194{
 195        struct memblock_region *new_array, *old_array;
 196        phys_addr_t old_alloc_size, new_alloc_size;
 197        phys_addr_t old_size, new_size, addr;
 198        int use_slab = slab_is_available();
 199        int *in_slab;
 200
 201        /* We don't allow resizing until we know about the reserved regions
 202         * of memory that aren't suitable for allocation
 203         */
 204        if (!memblock_can_resize)
 205                return -1;
 206
 207        /* Calculate new doubled size */
 208        old_size = type->max * sizeof(struct memblock_region);
 209        new_size = old_size << 1;
 210        /*
 211         * We need to allocated new one align to PAGE_SIZE,
 212         *   so we can free them completely later.
 213         */
 214        old_alloc_size = PAGE_ALIGN(old_size);
 215        new_alloc_size = PAGE_ALIGN(new_size);
 216
 217        /* Retrieve the slab flag */
 218        if (type == &memblock.memory)
 219                in_slab = &memblock_memory_in_slab;
 220        else
 221                in_slab = &memblock_reserved_in_slab;
 222
 223        /* Try to find some space for it.
 224         *
 225         * WARNING: We assume that either slab_is_available() and we use it or
 226         * we use MEMBLOCK for allocations. That means that this is unsafe to
 227         * use when bootmem is currently active (unless bootmem itself is
 228         * implemented on top of MEMBLOCK which isn't the case yet)
 229         *
 230         * This should however not be an issue for now, as we currently only
 231         * call into MEMBLOCK while it's still active, or much later when slab
 232         * is active for memory hotplug operations
 233         */
 234        if (use_slab) {
 235                new_array = kmalloc(new_size, GFP_KERNEL);
 236                addr = new_array ? __pa(new_array) : 0;
 237        } else {
 238                /* only exclude range when trying to double reserved.regions */
 239                if (type != &memblock.reserved)
 240                        new_area_start = new_area_size = 0;
 241
 242                addr = memblock_find_in_range(new_area_start + new_area_size,
 243                                                memblock.current_limit,
 244                                                new_alloc_size, PAGE_SIZE);
 245                if (!addr && new_area_size)
 246                        addr = memblock_find_in_range(0,
 247                                min(new_area_start, memblock.current_limit),
 248                                new_alloc_size, PAGE_SIZE);
 249
 250                new_array = addr ? __va(addr) : NULL;
 251        }
 252        if (!addr) {
 253                pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
 254                       memblock_type_name(type), type->max, type->max * 2);
 255                return -1;
 256        }
 257
 258        memblock_dbg("memblock: %s is doubled to %ld at [%#010llx-%#010llx]",
 259                        memblock_type_name(type), type->max * 2, (u64)addr,
 260                        (u64)addr + new_size - 1);
 261
 262        /*
 263         * Found space, we now need to move the array over before we add the
 264         * reserved region since it may be our reserved array itself that is
 265         * full.
 266         */
 267        memcpy(new_array, type->regions, old_size);
 268        memset(new_array + type->max, 0, old_size);
 269        old_array = type->regions;
 270        type->regions = new_array;
 271        type->max <<= 1;
 272
 273        /* Free old array. We needn't free it if the array is the static one */
 274        if (*in_slab)
 275                kfree(old_array);
 276        else if (old_array != memblock_memory_init_regions &&
 277                 old_array != memblock_reserved_init_regions)
 278                memblock_free(__pa(old_array), old_alloc_size);
 279
 280        /*
 281         * Reserve the new array if that comes from the memblock.  Otherwise, we
 282         * needn't do it
 283         */
 284        if (!use_slab)
 285                BUG_ON(memblock_reserve(addr, new_alloc_size));
 286
 287        /* Update slab flag */
 288        *in_slab = use_slab;
 289
 290        return 0;
 291}
 292
 293/**
 294 * memblock_merge_regions - merge neighboring compatible regions
 295 * @type: memblock type to scan
 296 *
 297 * Scan @type and merge neighboring compatible regions.
 298 */
 299static void __init_memblock memblock_merge_regions(struct memblock_type *type)
 300{
 301        int i = 0;
 302
 303        /* cnt never goes below 1 */
 304        while (i < type->cnt - 1) {
 305                struct memblock_region *this = &type->regions[i];
 306                struct memblock_region *next = &type->regions[i + 1];
 307
 308                if (this->base + this->size != next->base ||
 309                    memblock_get_region_node(this) !=
 310                    memblock_get_region_node(next)) {
 311                        BUG_ON(this->base + this->size > next->base);
 312                        i++;
 313                        continue;
 314                }
 315
 316                this->size += next->size;
 317                /* move forward from next + 1, index of which is i + 2 */
 318                memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));
 319                type->cnt--;
 320        }
 321}
 322
 323/**
 324 * memblock_insert_region - insert new memblock region
 325 * @type:       memblock type to insert into
 326 * @idx:        index for the insertion point
 327 * @base:       base address of the new region
 328 * @size:       size of the new region
 329 * @nid:        node id of the new region
 330 *
 331 * Insert new memblock region [@base,@base+@size) into @type at @idx.
 332 * @type must already have extra room to accomodate the new region.
 333 */
 334static void __init_memblock memblock_insert_region(struct memblock_type *type,
 335                                                   int idx, phys_addr_t base,
 336                                                   phys_addr_t size, int nid)
 337{
 338        struct memblock_region *rgn = &type->regions[idx];
 339
 340        BUG_ON(type->cnt >= type->max);
 341        memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
 342        rgn->base = base;
 343        rgn->size = size;
 344        memblock_set_region_node(rgn, nid);
 345        type->cnt++;
 346        type->total_size += size;
 347}
 348
 349/**
 350 * memblock_add_region - add new memblock region
 351 * @type: memblock type to add new region into
 352 * @base: base address of the new region
 353 * @size: size of the new region
 354 * @nid: nid of the new region
 355 *
 356 * Add new memblock region [@base,@base+@size) into @type.  The new region
 357 * is allowed to overlap with existing ones - overlaps don't affect already
 358 * existing regions.  @type is guaranteed to be minimal (all neighbouring
 359 * compatible regions are merged) after the addition.
 360 *
 361 * RETURNS:
 362 * 0 on success, -errno on failure.
 363 */
 364static int __init_memblock memblock_add_region(struct memblock_type *type,
 365                                phys_addr_t base, phys_addr_t size, int nid)
 366{
 367        bool insert = false;
 368        phys_addr_t obase = base;
 369        phys_addr_t end = base + memblock_cap_size(base, &size);
 370        int i, nr_new;
 371
 372        if (!size)
 373                return 0;
 374
 375        /* special case for empty array */
 376        if (type->regions[0].size == 0) {
 377                WARN_ON(type->cnt != 1 || type->total_size);
 378                type->regions[0].base = base;
 379                type->regions[0].size = size;
 380                memblock_set_region_node(&type->regions[0], nid);
 381                type->total_size = size;
 382                return 0;
 383        }
 384repeat:
 385        /*
 386         * The following is executed twice.  Once with %false @insert and
 387         * then with %true.  The first counts the number of regions needed
 388         * to accomodate the new area.  The second actually inserts them.
 389         */
 390        base = obase;
 391        nr_new = 0;
 392
 393        for (i = 0; i < type->cnt; i++) {
 394                struct memblock_region *rgn = &type->regions[i];
 395                phys_addr_t rbase = rgn->base;
 396                phys_addr_t rend = rbase + rgn->size;
 397
 398                if (rbase >= end)
 399                        break;
 400                if (rend <= base)
 401                        continue;
 402                /*
 403                 * @rgn overlaps.  If it separates the lower part of new
 404                 * area, insert that portion.
 405                 */
 406                if (rbase > base) {
 407                        nr_new++;
 408                        if (insert)
 409                                memblock_insert_region(type, i++, base,
 410                                                       rbase - base, nid);
 411                }
 412                /* area below @rend is dealt with, forget about it */
 413                base = min(rend, end);
 414        }
 415
 416        /* insert the remaining portion */
 417        if (base < end) {
 418                nr_new++;
 419                if (insert)
 420                        memblock_insert_region(type, i, base, end - base, nid);
 421        }
 422
 423        /*
 424         * If this was the first round, resize array and repeat for actual
 425         * insertions; otherwise, merge and return.
 426         */
 427        if (!insert) {
 428                while (type->cnt + nr_new > type->max)
 429                        if (memblock_double_array(type, obase, size) < 0)
 430                                return -ENOMEM;
 431                insert = true;
 432                goto repeat;
 433        } else {
 434                memblock_merge_regions(type);
 435                return 0;
 436        }
 437}
 438
 439int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
 440                                       int nid)
 441{
 442        return memblock_add_region(&memblock.memory, base, size, nid);
 443}
 444
 445int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
 446{
 447        return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);
 448}
 449
 450/**
 451 * memblock_isolate_range - isolate given range into disjoint memblocks
 452 * @type: memblock type to isolate range for
 453 * @base: base of range to isolate
 454 * @size: size of range to isolate
 455 * @start_rgn: out parameter for the start of isolated region
 456 * @end_rgn: out parameter for the end of isolated region
 457 *
 458 * Walk @type and ensure that regions don't cross the boundaries defined by
 459 * [@base,@base+@size).  Crossing regions are split at the boundaries,
 460 * which may create at most two more regions.  The index of the first
 461 * region inside the range is returned in *@start_rgn and end in *@end_rgn.
 462 *
 463 * RETURNS:
 464 * 0 on success, -errno on failure.
 465 */
 466static int __init_memblock memblock_isolate_range(struct memblock_type *type,
 467                                        phys_addr_t base, phys_addr_t size,
 468                                        int *start_rgn, int *end_rgn)
 469{
 470        phys_addr_t end = base + memblock_cap_size(base, &size);
 471        int i;
 472
 473        *start_rgn = *end_rgn = 0;
 474
 475        if (!size)
 476                return 0;
 477
 478        /* we'll create at most two more regions */
 479        while (type->cnt + 2 > type->max)
 480                if (memblock_double_array(type, base, size) < 0)
 481                        return -ENOMEM;
 482
 483        for (i = 0; i < type->cnt; i++) {
 484                struct memblock_region *rgn = &type->regions[i];
 485                phys_addr_t rbase = rgn->base;
 486                phys_addr_t rend = rbase + rgn->size;
 487
 488                if (rbase >= end)
 489                        break;
 490                if (rend <= base)
 491                        continue;
 492
 493                if (rbase < base) {
 494                        /*
 495                         * @rgn intersects from below.  Split and continue
 496                         * to process the next region - the new top half.
 497                         */
 498                        rgn->base = base;
 499                        rgn->size -= base - rbase;
 500                        type->total_size -= base - rbase;
 501                        memblock_insert_region(type, i, rbase, base - rbase,
 502                                               memblock_get_region_node(rgn));
 503                } else if (rend > end) {
 504                        /*
 505                         * @rgn intersects from above.  Split and redo the
 506                         * current region - the new bottom half.
 507                         */
 508                        rgn->base = end;
 509                        rgn->size -= end - rbase;
 510                        type->total_size -= end - rbase;
 511                        memblock_insert_region(type, i--, rbase, end - rbase,
 512                                               memblock_get_region_node(rgn));
 513                } else {
 514                        /* @rgn is fully contained, record it */
 515                        if (!*end_rgn)
 516                                *start_rgn = i;
 517                        *end_rgn = i + 1;
 518                }
 519        }
 520
 521        return 0;
 522}
 523
 524static int __init_memblock __memblock_remove(struct memblock_type *type,
 525                                             phys_addr_t base, phys_addr_t size)
 526{
 527        int start_rgn, end_rgn;
 528        int i, ret;
 529
 530        ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
 531        if (ret)
 532                return ret;
 533
 534        for (i = end_rgn - 1; i >= start_rgn; i--)
 535                memblock_remove_region(type, i);
 536        return 0;
 537}
 538
 539int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
 540{
 541        return __memblock_remove(&memblock.memory, base, size);
 542}
 543
 544int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
 545{
 546        memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF\n",
 547                     (unsigned long long)base,
 548                     (unsigned long long)base + size,
 549                     (void *)_RET_IP_);
 550
 551        return __memblock_remove(&memblock.reserved, base, size);
 552}
 553
 554int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 555{
 556        struct memblock_type *_rgn = &memblock.reserved;
 557
 558        memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
 559                     (unsigned long long)base,
 560                     (unsigned long long)base + size,
 561                     (void *)_RET_IP_);
 562
 563        return memblock_add_region(_rgn, base, size, MAX_NUMNODES);
 564}
 565
 566/**
 567 * __next_free_mem_range - next function for for_each_free_mem_range()
 568 * @idx: pointer to u64 loop variable
 569 * @nid: node selector, %MAX_NUMNODES for all nodes
 570 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
 571 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
 572 * @out_nid: ptr to int for nid of the range, can be %NULL
 573 *
 574 * Find the first free area from *@idx which matches @nid, fill the out
 575 * parameters, and update *@idx for the next iteration.  The lower 32bit of
 576 * *@idx contains index into memory region and the upper 32bit indexes the
 577 * areas before each reserved region.  For example, if reserved regions
 578 * look like the following,
 579 *
 580 *      0:[0-16), 1:[32-48), 2:[128-130)
 581 *
 582 * The upper 32bit indexes the following regions.
 583 *
 584 *      0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
 585 *
 586 * As both region arrays are sorted, the function advances the two indices
 587 * in lockstep and returns each intersection.
 588 */
 589void __init_memblock __next_free_mem_range(u64 *idx, int nid,
 590                                           phys_addr_t *out_start,
 591                                           phys_addr_t *out_end, int *out_nid)
 592{
 593        struct memblock_type *mem = &memblock.memory;
 594        struct memblock_type *rsv = &memblock.reserved;
 595        int mi = *idx & 0xffffffff;
 596        int ri = *idx >> 32;
 597
 598        for ( ; mi < mem->cnt; mi++) {
 599                struct memblock_region *m = &mem->regions[mi];
 600                phys_addr_t m_start = m->base;
 601                phys_addr_t m_end = m->base + m->size;
 602
 603                /* only memory regions are associated with nodes, check it */
 604                if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
 605                        continue;
 606
 607                /* scan areas before each reservation for intersection */
 608                for ( ; ri < rsv->cnt + 1; ri++) {
 609                        struct memblock_region *r = &rsv->regions[ri];
 610                        phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
 611                        phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
 612
 613                        /* if ri advanced past mi, break out to advance mi */
 614                        if (r_start >= m_end)
 615                                break;
 616                        /* if the two regions intersect, we're done */
 617                        if (m_start < r_end) {
 618                                if (out_start)
 619                                        *out_start = max(m_start, r_start);
 620                                if (out_end)
 621                                        *out_end = min(m_end, r_end);
 622                                if (out_nid)
 623                                        *out_nid = memblock_get_region_node(m);
 624                                /*
 625                                 * The region which ends first is advanced
 626                                 * for the next iteration.
 627                                 */
 628                                if (m_end <= r_end)
 629                                        mi++;
 630                                else
 631                                        ri++;
 632                                *idx = (u32)mi | (u64)ri << 32;
 633                                return;
 634                        }
 635                }
 636        }
 637
 638        /* signal end of iteration */
 639        *idx = ULLONG_MAX;
 640}
 641
 642/**
 643 * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
 644 * @idx: pointer to u64 loop variable
 645 * @nid: nid: node selector, %MAX_NUMNODES for all nodes
 646 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
 647 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
 648 * @out_nid: ptr to int for nid of the range, can be %NULL
 649 *
 650 * Reverse of __next_free_mem_range().
 651 */
 652void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
 653                                           phys_addr_t *out_start,
 654                                           phys_addr_t *out_end, int *out_nid)
 655{
 656        struct memblock_type *mem = &memblock.memory;
 657        struct memblock_type *rsv = &memblock.reserved;
 658        int mi = *idx & 0xffffffff;
 659        int ri = *idx >> 32;
 660
 661        if (*idx == (u64)ULLONG_MAX) {
 662                mi = mem->cnt - 1;
 663                ri = rsv->cnt;
 664        }
 665
 666        for ( ; mi >= 0; mi--) {
 667                struct memblock_region *m = &mem->regions[mi];
 668                phys_addr_t m_start = m->base;
 669                phys_addr_t m_end = m->base + m->size;
 670
 671                /* only memory regions are associated with nodes, check it */
 672                if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
 673                        continue;
 674
 675                /* scan areas before each reservation for intersection */
 676                for ( ; ri >= 0; ri--) {
 677                        struct memblock_region *r = &rsv->regions[ri];
 678                        phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
 679                        phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
 680
 681                        /* if ri advanced past mi, break out to advance mi */
 682                        if (r_end <= m_start)
 683                                break;
 684                        /* if the two regions intersect, we're done */
 685                        if (m_end > r_start) {
 686                                if (out_start)
 687                                        *out_start = max(m_start, r_start);
 688                                if (out_end)
 689                                        *out_end = min(m_end, r_end);
 690                                if (out_nid)
 691                                        *out_nid = memblock_get_region_node(m);
 692
 693                                if (m_start >= r_start)
 694                                        mi--;
 695                                else
 696                                        ri--;
 697                                *idx = (u32)mi | (u64)ri << 32;
 698                                return;
 699                        }
 700                }
 701        }
 702
 703        *idx = ULLONG_MAX;
 704}
 705
 706#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 707/*
 708 * Common iterator interface used to define for_each_mem_range().
 709 */
 710void __init_memblock __next_mem_pfn_range(int *idx, int nid,
 711                                unsigned long *out_start_pfn,
 712                                unsigned long *out_end_pfn, int *out_nid)
 713{
 714        struct memblock_type *type = &memblock.memory;
 715        struct memblock_region *r;
 716
 717        while (++*idx < type->cnt) {
 718                r = &type->regions[*idx];
 719
 720                if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
 721                        continue;
 722                if (nid == MAX_NUMNODES || nid == r->nid)
 723                        break;
 724        }
 725        if (*idx >= type->cnt) {
 726                *idx = -1;
 727                return;
 728        }
 729
 730        if (out_start_pfn)
 731                *out_start_pfn = PFN_UP(r->base);
 732        if (out_end_pfn)
 733                *out_end_pfn = PFN_DOWN(r->base + r->size);
 734        if (out_nid)
 735                *out_nid = r->nid;
 736}
 737
 738/**
 739 * memblock_set_node - set node ID on memblock regions
 740 * @base: base of area to set node ID for
 741 * @size: size of area to set node ID for
 742 * @nid: node ID to set
 743 *
 744 * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
 745 * Regions which cross the area boundaries are split as necessary.
 746 *
 747 * RETURNS:
 748 * 0 on success, -errno on failure.
 749 */
 750int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
 751                                      int nid)
 752{
 753        struct memblock_type *type = &memblock.memory;
 754        int start_rgn, end_rgn;
 755        int i, ret;
 756
 757        ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
 758        if (ret)
 759                return ret;
 760
 761        for (i = start_rgn; i < end_rgn; i++)
 762                memblock_set_region_node(&type->regions[i], nid);
 763
 764        memblock_merge_regions(type);
 765        return 0;
 766}
 767#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
 768
 769static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
 770                                        phys_addr_t align, phys_addr_t max_addr,
 771                                        int nid)
 772{
 773        phys_addr_t found;
 774
 775        if (WARN_ON(!align))
 776                align = __alignof__(long long);
 777
 778        /* align @size to avoid excessive fragmentation on reserved array */
 779        size = round_up(size, align);
 780
 781        found = memblock_find_in_range_node(0, max_addr, size, align, nid);
 782        if (found && !memblock_reserve(found, size))
 783                return found;
 784
 785        return 0;
 786}
 787
 788phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
 789{
 790        return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 791}
 792
 793phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
 794{
 795        return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
 796}
 797
 798phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
 799{
 800        phys_addr_t alloc;
 801
 802        alloc = __memblock_alloc_base(size, align, max_addr);
 803
 804        if (alloc == 0)
 805                panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
 806                      (unsigned long long) size, (unsigned long long) max_addr);
 807
 808        return alloc;
 809}
 810
 811phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
 812{
 813        return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 814}
 815
 816phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
 817{
 818        phys_addr_t res = memblock_alloc_nid(size, align, nid);
 819
 820        if (res)
 821                return res;
 822        return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 823}
 824
 825
 826/*
 827 * Remaining API functions
 828 */
 829
 830phys_addr_t __init memblock_phys_mem_size(void)
 831{
 832        return memblock.memory.total_size;
 833}
 834
 835phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
 836{
 837        unsigned long pages = 0;
 838        struct memblock_region *r;
 839        unsigned long start_pfn, end_pfn;
 840
 841        for_each_memblock(memory, r) {
 842                start_pfn = memblock_region_memory_base_pfn(r);
 843                end_pfn = memblock_region_memory_end_pfn(r);
 844                start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
 845                end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
 846                pages += end_pfn - start_pfn;
 847        }
 848
 849        return (phys_addr_t)pages << PAGE_SHIFT;
 850}
 851
 852/* lowest address */
 853phys_addr_t __init_memblock memblock_start_of_DRAM(void)
 854{
 855        return memblock.memory.regions[0].base;
 856}
 857
 858phys_addr_t __init_memblock memblock_end_of_DRAM(void)
 859{
 860        int idx = memblock.memory.cnt - 1;
 861
 862        return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
 863}
 864
 865void __init memblock_enforce_memory_limit(phys_addr_t limit)
 866{
 867        unsigned long i;
 868        phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
 869
 870        if (!limit)
 871                return;
 872
 873        /* find out max address */
 874        for (i = 0; i < memblock.memory.cnt; i++) {
 875                struct memblock_region *r = &memblock.memory.regions[i];
 876
 877                if (limit <= r->size) {
 878                        max_addr = r->base + limit;
 879                        break;
 880                }
 881                limit -= r->size;
 882        }
 883
 884        /* truncate both memory and reserved regions */
 885        __memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
 886        __memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
 887}
 888
 889static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
 890{
 891        unsigned int left = 0, right = type->cnt;
 892
 893        do {
 894                unsigned int mid = (right + left) / 2;
 895
 896                if (addr < type->regions[mid].base)
 897                        right = mid;
 898                else if (addr >= (type->regions[mid].base +
 899                                  type->regions[mid].size))
 900                        left = mid + 1;
 901                else
 902                        return mid;
 903        } while (left < right);
 904        return -1;
 905}
 906
 907int __init memblock_is_reserved(phys_addr_t addr)
 908{
 909        return memblock_search(&memblock.reserved, addr) != -1;
 910}
 911
 912int __init_memblock memblock_is_memory(phys_addr_t addr)
 913{
 914        return memblock_search(&memblock.memory, addr) != -1;
 915}
 916
 917#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 918int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
 919                         unsigned long *start_pfn, unsigned long *end_pfn)
 920{
 921        struct memblock_type *type = &memblock.memory;
 922        int mid = memblock_search(type, (phys_addr_t)pfn << PAGE_SHIFT);
 923
 924        if (mid == -1)
 925                return -1;
 926
 927        *start_pfn = type->regions[mid].base >> PAGE_SHIFT;
 928        *end_pfn = (type->regions[mid].base + type->regions[mid].size)
 929                        >> PAGE_SHIFT;
 930
 931        return type->regions[mid].nid;
 932}
 933#endif
 934
 935/**
 936 * memblock_is_region_memory - check if a region is a subset of memory
 937 * @base: base of region to check
 938 * @size: size of region to check
 939 *
 940 * Check if the region [@base, @base+@size) is a subset of a memory block.
 941 *
 942 * RETURNS:
 943 * 0 if false, non-zero if true
 944 */
 945int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
 946{
 947        int idx = memblock_search(&memblock.memory, base);
 948        phys_addr_t end = base + memblock_cap_size(base, &size);
 949
 950        if (idx == -1)
 951                return 0;
 952        return memblock.memory.regions[idx].base <= base &&
 953                (memblock.memory.regions[idx].base +
 954                 memblock.memory.regions[idx].size) >= end;
 955}
 956
 957/**
 958 * memblock_is_region_reserved - check if a region intersects reserved memory
 959 * @base: base of region to check
 960 * @size: size of region to check
 961 *
 962 * Check if the region [@base, @base+@size) intersects a reserved memory block.
 963 *
 964 * RETURNS:
 965 * 0 if false, non-zero if true
 966 */
 967int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
 968{
 969        memblock_cap_size(base, &size);
 970        return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
 971}
 972
 973void __init_memblock memblock_trim_memory(phys_addr_t align)
 974{
 975        int i;
 976        phys_addr_t start, end, orig_start, orig_end;
 977        struct memblock_type *mem = &memblock.memory;
 978
 979        for (i = 0; i < mem->cnt; i++) {
 980                orig_start = mem->regions[i].base;
 981                orig_end = mem->regions[i].base + mem->regions[i].size;
 982                start = round_up(orig_start, align);
 983                end = round_down(orig_end, align);
 984
 985                if (start == orig_start && end == orig_end)
 986                        continue;
 987
 988                if (start < end) {
 989                        mem->regions[i].base = start;
 990                        mem->regions[i].size = end - start;
 991                } else {
 992                        memblock_remove_region(mem, i);
 993                        i--;
 994                }
 995        }
 996}
 997
 998void __init_memblock memblock_set_current_limit(phys_addr_t limit)
 999{
1000        memblock.current_limit = limit;
1001}
1002
1003static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
1004{
1005        unsigned long long base, size;
1006        int i;
1007
1008        pr_info(" %s.cnt  = 0x%lx\n", name, type->cnt);
1009
1010        for (i = 0; i < type->cnt; i++) {
1011                struct memblock_region *rgn = &type->regions[i];
1012                char nid_buf[32] = "";
1013
1014                base = rgn->base;
1015                size = rgn->size;
1016#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
1017                if (memblock_get_region_node(rgn) != MAX_NUMNODES)
1018                        snprintf(nid_buf, sizeof(nid_buf), " on node %d",
1019                                 memblock_get_region_node(rgn));
1020#endif
1021                pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
1022                        name, i, base, base + size - 1, size, nid_buf);
1023        }
1024}
1025
1026void __init_memblock __memblock_dump_all(void)
1027{
1028        pr_info("MEMBLOCK configuration:\n");
1029        pr_info(" memory size = %#llx reserved size = %#llx\n",
1030                (unsigned long long)memblock.memory.total_size,
1031                (unsigned long long)memblock.reserved.total_size);
1032
1033        memblock_dump(&memblock.memory, "memory");
1034        memblock_dump(&memblock.reserved, "reserved");
1035}
1036
1037void __init memblock_allow_resize(void)
1038{
1039        memblock_can_resize = 1;
1040}
1041
1042static int __init early_memblock(char *p)
1043{
1044        if (p && strstr(p, "debug"))
1045                memblock_debug = 1;
1046        return 0;
1047}
1048early_param("memblock", early_memblock);
1049
1050#if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
1051
1052static int memblock_debug_show(struct seq_file *m, void *private)
1053{
1054        struct memblock_type *type = m->private;
1055        struct memblock_region *reg;
1056        int i;
1057
1058        for (i = 0; i < type->cnt; i++) {
1059                reg = &type->regions[i];
1060                seq_printf(m, "%4d: ", i);
1061                if (sizeof(phys_addr_t) == 4)
1062                        seq_printf(m, "0x%08lx..0x%08lx\n",
1063                                   (unsigned long)reg->base,
1064                                   (unsigned long)(reg->base + reg->size - 1));
1065                else
1066                        seq_printf(m, "0x%016llx..0x%016llx\n",
1067                                   (unsigned long long)reg->base,
1068                                   (unsigned long long)(reg->base + reg->size - 1));
1069
1070        }
1071        return 0;
1072}
1073
1074static int memblock_debug_open(struct inode *inode, struct file *file)
1075{
1076        return single_open(file, memblock_debug_show, inode->i_private);
1077}
1078
1079static const struct file_operations memblock_debug_fops = {
1080        .open = memblock_debug_open,
1081        .read = seq_read,
1082        .llseek = seq_lseek,
1083        .release = single_release,
1084};
1085
1086static int __init memblock_init_debugfs(void)
1087{
1088        struct dentry *root = debugfs_create_dir("memblock", NULL);
1089        if (!root)
1090                return -ENXIO;
1091        debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
1092        debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
1093
1094        return 0;
1095}
1096__initcall(memblock_init_debugfs);
1097
1098#endif /* CONFIG_DEBUG_FS */
1099