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 use
 226         * when bootmem is currently active (unless bootmem itself is implemented
 227         * 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 is
 231         * 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) : 0;
 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 array is doubled to %ld at [%#010llx-%#010llx]",
 258                 memblock_type_name(type), type->max * 2, (u64)addr, (u64)addr + new_size - 1);
 259
 260        /* Found space, we now need to move the array over before
 261         * we add the reserved region since it may be our reserved
 262         * array itself that is full.
 263         */
 264        memcpy(new_array, type->regions, old_size);
 265        memset(new_array + type->max, 0, old_size);
 266        old_array = type->regions;
 267        type->regions = new_array;
 268        type->max <<= 1;
 269
 270        /* Free old array. We needn't free it if the array is the
 271         * static one
 272         */
 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        /* Reserve the new array if that comes from the memblock.
 280         * Otherwise, we needn't do it
 281         */
 282        if (!use_slab)
 283                BUG_ON(memblock_reserve(addr, new_alloc_size));
 284
 285        /* Update slab flag */
 286        *in_slab = use_slab;
 287
 288        return 0;
 289}
 290
 291/**
 292 * memblock_merge_regions - merge neighboring compatible regions
 293 * @type: memblock type to scan
 294 *
 295 * Scan @type and merge neighboring compatible regions.
 296 */
 297static void __init_memblock memblock_merge_regions(struct memblock_type *type)
 298{
 299        int i = 0;
 300
 301        /* cnt never goes below 1 */
 302        while (i < type->cnt - 1) {
 303                struct memblock_region *this = &type->regions[i];
 304                struct memblock_region *next = &type->regions[i + 1];
 305
 306                if (this->base + this->size != next->base ||
 307                    memblock_get_region_node(this) !=
 308                    memblock_get_region_node(next)) {
 309                        BUG_ON(this->base + this->size > next->base);
 310                        i++;
 311                        continue;
 312                }
 313
 314                this->size += next->size;
 315                memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next));
 316                type->cnt--;
 317        }
 318}
 319
 320/**
 321 * memblock_insert_region - insert new memblock region
 322 * @type: memblock type to insert into
 323 * @idx: index for the insertion point
 324 * @base: base address of the new region
 325 * @size: size of the new region
 326 *
 327 * Insert new memblock region [@base,@base+@size) into @type at @idx.
 328 * @type must already have extra room to accomodate the new region.
 329 */
 330static void __init_memblock memblock_insert_region(struct memblock_type *type,
 331                                                   int idx, phys_addr_t base,
 332                                                   phys_addr_t size, int nid)
 333{
 334        struct memblock_region *rgn = &type->regions[idx];
 335
 336        BUG_ON(type->cnt >= type->max);
 337        memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
 338        rgn->base = base;
 339        rgn->size = size;
 340        memblock_set_region_node(rgn, nid);
 341        type->cnt++;
 342        type->total_size += size;
 343}
 344
 345/**
 346 * memblock_add_region - add new memblock region
 347 * @type: memblock type to add new region into
 348 * @base: base address of the new region
 349 * @size: size of the new region
 350 * @nid: nid of the new region
 351 *
 352 * Add new memblock region [@base,@base+@size) into @type.  The new region
 353 * is allowed to overlap with existing ones - overlaps don't affect already
 354 * existing regions.  @type is guaranteed to be minimal (all neighbouring
 355 * compatible regions are merged) after the addition.
 356 *
 357 * RETURNS:
 358 * 0 on success, -errno on failure.
 359 */
 360static int __init_memblock memblock_add_region(struct memblock_type *type,
 361                                phys_addr_t base, phys_addr_t size, int nid)
 362{
 363        bool insert = false;
 364        phys_addr_t obase = base;
 365        phys_addr_t end = base + memblock_cap_size(base, &size);
 366        int i, nr_new;
 367
 368        if (!size)
 369                return 0;
 370
 371        /* special case for empty array */
 372        if (type->regions[0].size == 0) {
 373                WARN_ON(type->cnt != 1 || type->total_size);
 374                type->regions[0].base = base;
 375                type->regions[0].size = size;
 376                memblock_set_region_node(&type->regions[0], nid);
 377                type->total_size = size;
 378                return 0;
 379        }
 380repeat:
 381        /*
 382         * The following is executed twice.  Once with %false @insert and
 383         * then with %true.  The first counts the number of regions needed
 384         * to accomodate the new area.  The second actually inserts them.
 385         */
 386        base = obase;
 387        nr_new = 0;
 388
 389        for (i = 0; i < type->cnt; i++) {
 390                struct memblock_region *rgn = &type->regions[i];
 391                phys_addr_t rbase = rgn->base;
 392                phys_addr_t rend = rbase + rgn->size;
 393
 394                if (rbase >= end)
 395                        break;
 396                if (rend <= base)
 397                        continue;
 398                /*
 399                 * @rgn overlaps.  If it separates the lower part of new
 400                 * area, insert that portion.
 401                 */
 402                if (rbase > base) {
 403                        nr_new++;
 404                        if (insert)
 405                                memblock_insert_region(type, i++, base,
 406                                                       rbase - base, nid);
 407                }
 408                /* area below @rend is dealt with, forget about it */
 409                base = min(rend, end);
 410        }
 411
 412        /* insert the remaining portion */
 413        if (base < end) {
 414                nr_new++;
 415                if (insert)
 416                        memblock_insert_region(type, i, base, end - base, nid);
 417        }
 418
 419        /*
 420         * If this was the first round, resize array and repeat for actual
 421         * insertions; otherwise, merge and return.
 422         */
 423        if (!insert) {
 424                while (type->cnt + nr_new > type->max)
 425                        if (memblock_double_array(type, obase, size) < 0)
 426                                return -ENOMEM;
 427                insert = true;
 428                goto repeat;
 429        } else {
 430                memblock_merge_regions(type);
 431                return 0;
 432        }
 433}
 434
 435int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
 436                                       int nid)
 437{
 438        return memblock_add_region(&memblock.memory, base, size, nid);
 439}
 440
 441int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
 442{
 443        return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);
 444}
 445
 446/**
 447 * memblock_isolate_range - isolate given range into disjoint memblocks
 448 * @type: memblock type to isolate range for
 449 * @base: base of range to isolate
 450 * @size: size of range to isolate
 451 * @start_rgn: out parameter for the start of isolated region
 452 * @end_rgn: out parameter for the end of isolated region
 453 *
 454 * Walk @type and ensure that regions don't cross the boundaries defined by
 455 * [@base,@base+@size).  Crossing regions are split at the boundaries,
 456 * which may create at most two more regions.  The index of the first
 457 * region inside the range is returned in *@start_rgn and end in *@end_rgn.
 458 *
 459 * RETURNS:
 460 * 0 on success, -errno on failure.
 461 */
 462static int __init_memblock memblock_isolate_range(struct memblock_type *type,
 463                                        phys_addr_t base, phys_addr_t size,
 464                                        int *start_rgn, int *end_rgn)
 465{
 466        phys_addr_t end = base + memblock_cap_size(base, &size);
 467        int i;
 468
 469        *start_rgn = *end_rgn = 0;
 470
 471        if (!size)
 472                return 0;
 473
 474        /* we'll create at most two more regions */
 475        while (type->cnt + 2 > type->max)
 476                if (memblock_double_array(type, base, size) < 0)
 477                        return -ENOMEM;
 478
 479        for (i = 0; i < type->cnt; i++) {
 480                struct memblock_region *rgn = &type->regions[i];
 481                phys_addr_t rbase = rgn->base;
 482                phys_addr_t rend = rbase + rgn->size;
 483
 484                if (rbase >= end)
 485                        break;
 486                if (rend <= base)
 487                        continue;
 488
 489                if (rbase < base) {
 490                        /*
 491                         * @rgn intersects from below.  Split and continue
 492                         * to process the next region - the new top half.
 493                         */
 494                        rgn->base = base;
 495                        rgn->size -= base - rbase;
 496                        type->total_size -= base - rbase;
 497                        memblock_insert_region(type, i, rbase, base - rbase,
 498                                               memblock_get_region_node(rgn));
 499                } else if (rend > end) {
 500                        /*
 501                         * @rgn intersects from above.  Split and redo the
 502                         * current region - the new bottom half.
 503                         */
 504                        rgn->base = end;
 505                        rgn->size -= end - rbase;
 506                        type->total_size -= end - rbase;
 507                        memblock_insert_region(type, i--, rbase, end - rbase,
 508                                               memblock_get_region_node(rgn));
 509                } else {
 510                        /* @rgn is fully contained, record it */
 511                        if (!*end_rgn)
 512                                *start_rgn = i;
 513                        *end_rgn = i + 1;
 514                }
 515        }
 516
 517        return 0;
 518}
 519
 520static int __init_memblock __memblock_remove(struct memblock_type *type,
 521                                             phys_addr_t base, phys_addr_t size)
 522{
 523        int start_rgn, end_rgn;
 524        int i, ret;
 525
 526        ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
 527        if (ret)
 528                return ret;
 529
 530        for (i = end_rgn - 1; i >= start_rgn; i--)
 531                memblock_remove_region(type, i);
 532        return 0;
 533}
 534
 535int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
 536{
 537        return __memblock_remove(&memblock.memory, base, size);
 538}
 539
 540int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
 541{
 542        memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF\n",
 543                     (unsigned long long)base,
 544                     (unsigned long long)base + size,
 545                     (void *)_RET_IP_);
 546
 547        return __memblock_remove(&memblock.reserved, base, size);
 548}
 549
 550int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 551{
 552        struct memblock_type *_rgn = &memblock.reserved;
 553
 554        memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF\n",
 555                     (unsigned long long)base,
 556                     (unsigned long long)base + size,
 557                     (void *)_RET_IP_);
 558
 559        return memblock_add_region(_rgn, base, size, MAX_NUMNODES);
 560}
 561
 562/**
 563 * __next_free_mem_range - next function for for_each_free_mem_range()
 564 * @idx: pointer to u64 loop variable
 565 * @nid: nid: node selector, %MAX_NUMNODES for all nodes
 566 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
 567 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
 568 * @out_nid: ptr to int for nid of the range, can be %NULL
 569 *
 570 * Find the first free area from *@idx which matches @nid, fill the out
 571 * parameters, and update *@idx for the next iteration.  The lower 32bit of
 572 * *@idx contains index into memory region and the upper 32bit indexes the
 573 * areas before each reserved region.  For example, if reserved regions
 574 * look like the following,
 575 *
 576 *      0:[0-16), 1:[32-48), 2:[128-130)
 577 *
 578 * The upper 32bit indexes the following regions.
 579 *
 580 *      0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
 581 *
 582 * As both region arrays are sorted, the function advances the two indices
 583 * in lockstep and returns each intersection.
 584 */
 585void __init_memblock __next_free_mem_range(u64 *idx, int nid,
 586                                           phys_addr_t *out_start,
 587                                           phys_addr_t *out_end, int *out_nid)
 588{
 589        struct memblock_type *mem = &memblock.memory;
 590        struct memblock_type *rsv = &memblock.reserved;
 591        int mi = *idx & 0xffffffff;
 592        int ri = *idx >> 32;
 593
 594        for ( ; mi < mem->cnt; mi++) {
 595                struct memblock_region *m = &mem->regions[mi];
 596                phys_addr_t m_start = m->base;
 597                phys_addr_t m_end = m->base + m->size;
 598
 599                /* only memory regions are associated with nodes, check it */
 600                if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
 601                        continue;
 602
 603                /* scan areas before each reservation for intersection */
 604                for ( ; ri < rsv->cnt + 1; ri++) {
 605                        struct memblock_region *r = &rsv->regions[ri];
 606                        phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
 607                        phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
 608
 609                        /* if ri advanced past mi, break out to advance mi */
 610                        if (r_start >= m_end)
 611                                break;
 612                        /* if the two regions intersect, we're done */
 613                        if (m_start < r_end) {
 614                                if (out_start)
 615                                        *out_start = max(m_start, r_start);
 616                                if (out_end)
 617                                        *out_end = min(m_end, r_end);
 618                                if (out_nid)
 619                                        *out_nid = memblock_get_region_node(m);
 620                                /*
 621                                 * The region which ends first is advanced
 622                                 * for the next iteration.
 623                                 */
 624                                if (m_end <= r_end)
 625                                        mi++;
 626                                else
 627                                        ri++;
 628                                *idx = (u32)mi | (u64)ri << 32;
 629                                return;
 630                        }
 631                }
 632        }
 633
 634        /* signal end of iteration */
 635        *idx = ULLONG_MAX;
 636}
 637
 638/**
 639 * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
 640 * @idx: pointer to u64 loop variable
 641 * @nid: nid: node selector, %MAX_NUMNODES for all nodes
 642 * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
 643 * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
 644 * @out_nid: ptr to int for nid of the range, can be %NULL
 645 *
 646 * Reverse of __next_free_mem_range().
 647 */
 648void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
 649                                           phys_addr_t *out_start,
 650                                           phys_addr_t *out_end, int *out_nid)
 651{
 652        struct memblock_type *mem = &memblock.memory;
 653        struct memblock_type *rsv = &memblock.reserved;
 654        int mi = *idx & 0xffffffff;
 655        int ri = *idx >> 32;
 656
 657        if (*idx == (u64)ULLONG_MAX) {
 658                mi = mem->cnt - 1;
 659                ri = rsv->cnt;
 660        }
 661
 662        for ( ; mi >= 0; mi--) {
 663                struct memblock_region *m = &mem->regions[mi];
 664                phys_addr_t m_start = m->base;
 665                phys_addr_t m_end = m->base + m->size;
 666
 667                /* only memory regions are associated with nodes, check it */
 668                if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
 669                        continue;
 670
 671                /* scan areas before each reservation for intersection */
 672                for ( ; ri >= 0; ri--) {
 673                        struct memblock_region *r = &rsv->regions[ri];
 674                        phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
 675                        phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
 676
 677                        /* if ri advanced past mi, break out to advance mi */
 678                        if (r_end <= m_start)
 679                                break;
 680                        /* if the two regions intersect, we're done */
 681                        if (m_end > r_start) {
 682                                if (out_start)
 683                                        *out_start = max(m_start, r_start);
 684                                if (out_end)
 685                                        *out_end = min(m_end, r_end);
 686                                if (out_nid)
 687                                        *out_nid = memblock_get_region_node(m);
 688
 689                                if (m_start >= r_start)
 690                                        mi--;
 691                                else
 692                                        ri--;
 693                                *idx = (u32)mi | (u64)ri << 32;
 694                                return;
 695                        }
 696                }
 697        }
 698
 699        *idx = ULLONG_MAX;
 700}
 701
 702#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 703/*
 704 * Common iterator interface used to define for_each_mem_range().
 705 */
 706void __init_memblock __next_mem_pfn_range(int *idx, int nid,
 707                                unsigned long *out_start_pfn,
 708                                unsigned long *out_end_pfn, int *out_nid)
 709{
 710        struct memblock_type *type = &memblock.memory;
 711        struct memblock_region *r;
 712
 713        while (++*idx < type->cnt) {
 714                r = &type->regions[*idx];
 715
 716                if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
 717                        continue;
 718                if (nid == MAX_NUMNODES || nid == r->nid)
 719                        break;
 720        }
 721        if (*idx >= type->cnt) {
 722                *idx = -1;
 723                return;
 724        }
 725
 726        if (out_start_pfn)
 727                *out_start_pfn = PFN_UP(r->base);
 728        if (out_end_pfn)
 729                *out_end_pfn = PFN_DOWN(r->base + r->size);
 730        if (out_nid)
 731                *out_nid = r->nid;
 732}
 733
 734/**
 735 * memblock_set_node - set node ID on memblock regions
 736 * @base: base of area to set node ID for
 737 * @size: size of area to set node ID for
 738 * @nid: node ID to set
 739 *
 740 * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
 741 * Regions which cross the area boundaries are split as necessary.
 742 *
 743 * RETURNS:
 744 * 0 on success, -errno on failure.
 745 */
 746int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
 747                                      int nid)
 748{
 749        struct memblock_type *type = &memblock.memory;
 750        int start_rgn, end_rgn;
 751        int i, ret;
 752
 753        ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
 754        if (ret)
 755                return ret;
 756
 757        for (i = start_rgn; i < end_rgn; i++)
 758                type->regions[i].nid = nid;
 759
 760        memblock_merge_regions(type);
 761        return 0;
 762}
 763#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
 764
 765static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
 766                                        phys_addr_t align, phys_addr_t max_addr,
 767                                        int nid)
 768{
 769        phys_addr_t found;
 770
 771        /* align @size to avoid excessive fragmentation on reserved array */
 772        size = round_up(size, align);
 773
 774        found = memblock_find_in_range_node(0, max_addr, size, align, nid);
 775        if (found && !memblock_reserve(found, size))
 776                return found;
 777
 778        return 0;
 779}
 780
 781phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
 782{
 783        return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 784}
 785
 786phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
 787{
 788        return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
 789}
 790
 791phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
 792{
 793        phys_addr_t alloc;
 794
 795        alloc = __memblock_alloc_base(size, align, max_addr);
 796
 797        if (alloc == 0)
 798                panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
 799                      (unsigned long long) size, (unsigned long long) max_addr);
 800
 801        return alloc;
 802}
 803
 804phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
 805{
 806        return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 807}
 808
 809phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
 810{
 811        phys_addr_t res = memblock_alloc_nid(size, align, nid);
 812
 813        if (res)
 814                return res;
 815        return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 816}
 817
 818
 819/*
 820 * Remaining API functions
 821 */
 822
 823phys_addr_t __init memblock_phys_mem_size(void)
 824{
 825        return memblock.memory.total_size;
 826}
 827
 828/* lowest address */
 829phys_addr_t __init_memblock memblock_start_of_DRAM(void)
 830{
 831        return memblock.memory.regions[0].base;
 832}
 833
 834phys_addr_t __init_memblock memblock_end_of_DRAM(void)
 835{
 836        int idx = memblock.memory.cnt - 1;
 837
 838        return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
 839}
 840
 841void __init memblock_enforce_memory_limit(phys_addr_t limit)
 842{
 843        unsigned long i;
 844        phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
 845
 846        if (!limit)
 847                return;
 848
 849        /* find out max address */
 850        for (i = 0; i < memblock.memory.cnt; i++) {
 851                struct memblock_region *r = &memblock.memory.regions[i];
 852
 853                if (limit <= r->size) {
 854                        max_addr = r->base + limit;
 855                        break;
 856                }
 857                limit -= r->size;
 858        }
 859
 860        /* truncate both memory and reserved regions */
 861        __memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
 862        __memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);
 863}
 864
 865static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
 866{
 867        unsigned int left = 0, right = type->cnt;
 868
 869        do {
 870                unsigned int mid = (right + left) / 2;
 871
 872                if (addr < type->regions[mid].base)
 873                        right = mid;
 874                else if (addr >= (type->regions[mid].base +
 875                                  type->regions[mid].size))
 876                        left = mid + 1;
 877                else
 878                        return mid;
 879        } while (left < right);
 880        return -1;
 881}
 882
 883int __init memblock_is_reserved(phys_addr_t addr)
 884{
 885        return memblock_search(&memblock.reserved, addr) != -1;
 886}
 887
 888int __init_memblock memblock_is_memory(phys_addr_t addr)
 889{
 890        return memblock_search(&memblock.memory, addr) != -1;
 891}
 892
 893/**
 894 * memblock_is_region_memory - check if a region is a subset of memory
 895 * @base: base of region to check
 896 * @size: size of region to check
 897 *
 898 * Check if the region [@base, @base+@size) is a subset of a memory block.
 899 *
 900 * RETURNS:
 901 * 0 if false, non-zero if true
 902 */
 903int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
 904{
 905        int idx = memblock_search(&memblock.memory, base);
 906        phys_addr_t end = base + memblock_cap_size(base, &size);
 907
 908        if (idx == -1)
 909                return 0;
 910        return memblock.memory.regions[idx].base <= base &&
 911                (memblock.memory.regions[idx].base +
 912                 memblock.memory.regions[idx].size) >= end;
 913}
 914
 915/**
 916 * memblock_is_region_reserved - check if a region intersects reserved memory
 917 * @base: base of region to check
 918 * @size: size of region to check
 919 *
 920 * Check if the region [@base, @base+@size) intersects a reserved memory block.
 921 *
 922 * RETURNS:
 923 * 0 if false, non-zero if true
 924 */
 925int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
 926{
 927        memblock_cap_size(base, &size);
 928        return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
 929}
 930
 931
 932void __init_memblock memblock_set_current_limit(phys_addr_t limit)
 933{
 934        memblock.current_limit = limit;
 935}
 936
 937static void __init_memblock memblock_dump(struct memblock_type *type, char *name)
 938{
 939        unsigned long long base, size;
 940        int i;
 941
 942        pr_info(" %s.cnt  = 0x%lx\n", name, type->cnt);
 943
 944        for (i = 0; i < type->cnt; i++) {
 945                struct memblock_region *rgn = &type->regions[i];
 946                char nid_buf[32] = "";
 947
 948                base = rgn->base;
 949                size = rgn->size;
 950#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 951                if (memblock_get_region_node(rgn) != MAX_NUMNODES)
 952                        snprintf(nid_buf, sizeof(nid_buf), " on node %d",
 953                                 memblock_get_region_node(rgn));
 954#endif
 955                pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s\n",
 956                        name, i, base, base + size - 1, size, nid_buf);
 957        }
 958}
 959
 960void __init_memblock __memblock_dump_all(void)
 961{
 962        pr_info("MEMBLOCK configuration:\n");
 963        pr_info(" memory size = %#llx reserved size = %#llx\n",
 964                (unsigned long long)memblock.memory.total_size,
 965                (unsigned long long)memblock.reserved.total_size);
 966
 967        memblock_dump(&memblock.memory, "memory");
 968        memblock_dump(&memblock.reserved, "reserved");
 969}
 970
 971void __init memblock_allow_resize(void)
 972{
 973        memblock_can_resize = 1;
 974}
 975
 976static int __init early_memblock(char *p)
 977{
 978        if (p && strstr(p, "debug"))
 979                memblock_debug = 1;
 980        return 0;
 981}
 982early_param("memblock", early_memblock);
 983
 984#if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)
 985
 986static int memblock_debug_show(struct seq_file *m, void *private)
 987{
 988        struct memblock_type *type = m->private;
 989        struct memblock_region *reg;
 990        int i;
 991
 992        for (i = 0; i < type->cnt; i++) {
 993                reg = &type->regions[i];
 994                seq_printf(m, "%4d: ", i);
 995                if (sizeof(phys_addr_t) == 4)
 996                        seq_printf(m, "0x%08lx..0x%08lx\n",
 997                                   (unsigned long)reg->base,
 998                                   (unsigned long)(reg->base + reg->size - 1));
 999                else
1000                        seq_printf(m, "0x%016llx..0x%016llx\n",
1001                                   (unsigned long long)reg->base,
1002                                   (unsigned long long)(reg->base + reg->size - 1));
1003
1004        }
1005        return 0;
1006}
1007
1008static int memblock_debug_open(struct inode *inode, struct file *file)
1009{
1010        return single_open(file, memblock_debug_show, inode->i_private);
1011}
1012
1013static const struct file_operations memblock_debug_fops = {
1014        .open = memblock_debug_open,
1015        .read = seq_read,
1016        .llseek = seq_lseek,
1017        .release = single_release,
1018};
1019
1020static int __init memblock_init_debugfs(void)
1021{
1022        struct dentry *root = debugfs_create_dir("memblock", NULL);
1023        if (!root)
1024                return -ENXIO;
1025        debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
1026        debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
1027
1028        return 0;
1029}
1030__initcall(memblock_init_debugfs);
1031
1032#endif /* CONFIG_DEBUG_FS */
1033
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