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