Root/mm/memblock.c

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
23struct memblock memblock __initdata_memblock;
24
25int memblock_debug __initdata_memblock;
26int memblock_can_resize __initdata_memblock;
27static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS + 1] __initdata_memblock;
28static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS + 1] __initdata_memblock;
29
30/* inline so we don't get a warning when pr_debug is compiled out */
31static inline const char *memblock_type_name(struct memblock_type *type)
32{
33    if (type == &memblock.memory)
34        return "memory";
35    else if (type == &memblock.reserved)
36        return "reserved";
37    else
38        return "unknown";
39}
40
41/*
42 * Address comparison utilities
43 */
44
45static phys_addr_t __init_memblock memblock_align_down(phys_addr_t addr, phys_addr_t size)
46{
47    return addr & ~(size - 1);
48}
49
50static phys_addr_t __init_memblock memblock_align_up(phys_addr_t addr, phys_addr_t size)
51{
52    return (addr + (size - 1)) & ~(size - 1);
53}
54
55static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
56                       phys_addr_t base2, phys_addr_t size2)
57{
58    return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
59}
60
61long __init_memblock memblock_overlaps_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
62{
63    unsigned long i;
64
65    for (i = 0; i < type->cnt; i++) {
66        phys_addr_t rgnbase = type->regions[i].base;
67        phys_addr_t rgnsize = type->regions[i].size;
68        if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
69            break;
70    }
71
72    return (i < type->cnt) ? i : -1;
73}
74
75/*
76 * Find, allocate, deallocate or reserve unreserved regions. All allocations
77 * are top-down.
78 */
79
80static phys_addr_t __init_memblock memblock_find_region(phys_addr_t start, phys_addr_t end,
81                      phys_addr_t size, phys_addr_t align)
82{
83    phys_addr_t base, res_base;
84    long j;
85
86    /* In case, huge size is requested */
87    if (end < size)
88        return MEMBLOCK_ERROR;
89
90    base = memblock_align_down((end - size), align);
91
92    /* Prevent allocations returning 0 as it's also used to
93     * indicate an allocation failure
94     */
95    if (start == 0)
96        start = PAGE_SIZE;
97
98    while (start <= base) {
99        j = memblock_overlaps_region(&memblock.reserved, base, size);
100        if (j < 0)
101            return base;
102        res_base = memblock.reserved.regions[j].base;
103        if (res_base < size)
104            break;
105        base = memblock_align_down(res_base - size, align);
106    }
107
108    return MEMBLOCK_ERROR;
109}
110
111static phys_addr_t __init_memblock memblock_find_base(phys_addr_t size,
112            phys_addr_t align, phys_addr_t start, phys_addr_t end)
113{
114    long i;
115
116    BUG_ON(0 == size);
117
118    /* Pump up max_addr */
119    if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
120        end = memblock.current_limit;
121
122    /* We do a top-down search, this tends to limit memory
123     * fragmentation by keeping early boot allocs near the
124     * top of memory
125     */
126    for (i = memblock.memory.cnt - 1; i >= 0; i--) {
127        phys_addr_t memblockbase = memblock.memory.regions[i].base;
128        phys_addr_t memblocksize = memblock.memory.regions[i].size;
129        phys_addr_t bottom, top, found;
130
131        if (memblocksize < size)
132            continue;
133        if ((memblockbase + memblocksize) <= start)
134            break;
135        bottom = max(memblockbase, start);
136        top = min(memblockbase + memblocksize, end);
137        if (bottom >= top)
138            continue;
139        found = memblock_find_region(bottom, top, size, align);
140        if (found != MEMBLOCK_ERROR)
141            return found;
142    }
143    return MEMBLOCK_ERROR;
144}
145
146/*
147 * Find a free area with specified alignment in a specific range.
148 */
149u64 __init_memblock memblock_find_in_range(u64 start, u64 end, u64 size, u64 align)
150{
151    return memblock_find_base(size, align, start, end);
152}
153
154/*
155 * Free memblock.reserved.regions
156 */
157int __init_memblock memblock_free_reserved_regions(void)
158{
159    if (memblock.reserved.regions == memblock_reserved_init_regions)
160        return 0;
161
162    return memblock_free(__pa(memblock.reserved.regions),
163         sizeof(struct memblock_region) * memblock.reserved.max);
164}
165
166/*
167 * Reserve memblock.reserved.regions
168 */
169int __init_memblock memblock_reserve_reserved_regions(void)
170{
171    if (memblock.reserved.regions == memblock_reserved_init_regions)
172        return 0;
173
174    return memblock_reserve(__pa(memblock.reserved.regions),
175         sizeof(struct memblock_region) * memblock.reserved.max);
176}
177
178static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)
179{
180    unsigned long i;
181
182    for (i = r; i < type->cnt - 1; i++) {
183        type->regions[i].base = type->regions[i + 1].base;
184        type->regions[i].size = type->regions[i + 1].size;
185    }
186    type->cnt--;
187
188    /* Special case for empty arrays */
189    if (type->cnt == 0) {
190        type->cnt = 1;
191        type->regions[0].base = 0;
192        type->regions[0].size = 0;
193    }
194}
195
196/* Defined below but needed now */
197static long memblock_add_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size);
198
199static int __init_memblock memblock_double_array(struct memblock_type *type)
200{
201    struct memblock_region *new_array, *old_array;
202    phys_addr_t old_size, new_size, addr;
203    int use_slab = slab_is_available();
204
205    /* We don't allow resizing until we know about the reserved regions
206     * of memory that aren't suitable for allocation
207     */
208    if (!memblock_can_resize)
209        return -1;
210
211    /* Calculate new doubled size */
212    old_size = type->max * sizeof(struct memblock_region);
213    new_size = old_size << 1;
214
215    /* Try to find some space for it.
216     *
217     * WARNING: We assume that either slab_is_available() and we use it or
218     * we use MEMBLOCK for allocations. That means that this is unsafe to use
219     * when bootmem is currently active (unless bootmem itself is implemented
220     * on top of MEMBLOCK which isn't the case yet)
221     *
222     * This should however not be an issue for now, as we currently only
223     * call into MEMBLOCK while it's still active, or much later when slab is
224     * active for memory hotplug operations
225     */
226    if (use_slab) {
227        new_array = kmalloc(new_size, GFP_KERNEL);
228        addr = new_array == NULL ? MEMBLOCK_ERROR : __pa(new_array);
229    } else
230        addr = memblock_find_base(new_size, sizeof(phys_addr_t), 0, MEMBLOCK_ALLOC_ACCESSIBLE);
231    if (addr == MEMBLOCK_ERROR) {
232        pr_err("memblock: Failed to double %s array from %ld to %ld entries !\n",
233               memblock_type_name(type), type->max, type->max * 2);
234        return -1;
235    }
236    new_array = __va(addr);
237
238    memblock_dbg("memblock: %s array is doubled to %ld at [%#010llx-%#010llx]",
239         memblock_type_name(type), type->max * 2, (u64)addr, (u64)addr + new_size - 1);
240
241    /* Found space, we now need to move the array over before
242     * we add the reserved region since it may be our reserved
243     * array itself that is full.
244     */
245    memcpy(new_array, type->regions, old_size);
246    memset(new_array + type->max, 0, old_size);
247    old_array = type->regions;
248    type->regions = new_array;
249    type->max <<= 1;
250
251    /* If we use SLAB that's it, we are done */
252    if (use_slab)
253        return 0;
254
255    /* Add the new reserved region now. Should not fail ! */
256    BUG_ON(memblock_add_region(&memblock.reserved, addr, new_size));
257
258    /* If the array wasn't our static init one, then free it. We only do
259     * that before SLAB is available as later on, we don't know whether
260     * to use kfree or free_bootmem_pages(). Shouldn't be a big deal
261     * anyways
262     */
263    if (old_array != memblock_memory_init_regions &&
264        old_array != memblock_reserved_init_regions)
265        memblock_free(__pa(old_array), old_size);
266
267    return 0;
268}
269
270extern int __init_memblock __weak memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1,
271                      phys_addr_t addr2, phys_addr_t size2)
272{
273    return 1;
274}
275
276static long __init_memblock memblock_add_region(struct memblock_type *type,
277                        phys_addr_t base, phys_addr_t size)
278{
279    phys_addr_t end = base + size;
280    int i, slot = -1;
281
282    /* First try and coalesce this MEMBLOCK with others */
283    for (i = 0; i < type->cnt; i++) {
284        struct memblock_region *rgn = &type->regions[i];
285        phys_addr_t rend = rgn->base + rgn->size;
286
287        /* Exit if there's no possible hits */
288        if (rgn->base > end || rgn->size == 0)
289            break;
290
291        /* Check if we are fully enclosed within an existing
292         * block
293         */
294        if (rgn->base <= base && rend >= end)
295            return 0;
296
297        /* Check if we overlap or are adjacent with the bottom
298         * of a block.
299         */
300        if (base < rgn->base && end >= rgn->base) {
301            /* If we can't coalesce, create a new block */
302            if (!memblock_memory_can_coalesce(base, size,
303                              rgn->base,
304                              rgn->size)) {
305                /* Overlap & can't coalesce are mutually
306                 * exclusive, if you do that, be prepared
307                 * for trouble
308                 */
309                WARN_ON(end != rgn->base);
310                goto new_block;
311            }
312            /* We extend the bottom of the block down to our
313             * base
314             */
315            rgn->base = base;
316            rgn->size = rend - base;
317
318            /* Return if we have nothing else to allocate
319             * (fully coalesced)
320             */
321            if (rend >= end)
322                return 0;
323
324            /* We continue processing from the end of the
325             * coalesced block.
326             */
327            base = rend;
328            size = end - base;
329        }
330
331        /* Now check if we overlap or are adjacent with the
332         * top of a block
333         */
334        if (base <= rend && end >= rend) {
335            /* If we can't coalesce, create a new block */
336            if (!memblock_memory_can_coalesce(rgn->base,
337                              rgn->size,
338                              base, size)) {
339                /* Overlap & can't coalesce are mutually
340                 * exclusive, if you do that, be prepared
341                 * for trouble
342                 */
343                WARN_ON(rend != base);
344                goto new_block;
345            }
346            /* We adjust our base down to enclose the
347             * original block and destroy it. It will be
348             * part of our new allocation. Since we've
349             * freed an entry, we know we won't fail
350             * to allocate one later, so we won't risk
351             * losing the original block allocation.
352             */
353            size += (base - rgn->base);
354            base = rgn->base;
355            memblock_remove_region(type, i--);
356        }
357    }
358
359    /* If the array is empty, special case, replace the fake
360     * filler region and return
361     */
362    if ((type->cnt == 1) && (type->regions[0].size == 0)) {
363        type->regions[0].base = base;
364        type->regions[0].size = size;
365        return 0;
366    }
367
368 new_block:
369    /* If we are out of space, we fail. It's too late to resize the array
370     * but then this shouldn't have happened in the first place.
371     */
372    if (WARN_ON(type->cnt >= type->max))
373        return -1;
374
375    /* Couldn't coalesce the MEMBLOCK, so add it to the sorted table. */
376    for (i = type->cnt - 1; i >= 0; i--) {
377        if (base < type->regions[i].base) {
378            type->regions[i+1].base = type->regions[i].base;
379            type->regions[i+1].size = type->regions[i].size;
380        } else {
381            type->regions[i+1].base = base;
382            type->regions[i+1].size = size;
383            slot = i + 1;
384            break;
385        }
386    }
387    if (base < type->regions[0].base) {
388        type->regions[0].base = base;
389        type->regions[0].size = size;
390        slot = 0;
391    }
392    type->cnt++;
393
394    /* The array is full ? Try to resize it. If that fails, we undo
395     * our allocation and return an error
396     */
397    if (type->cnt == type->max && memblock_double_array(type)) {
398        BUG_ON(slot < 0);
399        memblock_remove_region(type, slot);
400        return -1;
401    }
402
403    return 0;
404}
405
406long __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
407{
408    return memblock_add_region(&memblock.memory, base, size);
409
410}
411
412static long __init_memblock __memblock_remove(struct memblock_type *type,
413                          phys_addr_t base, phys_addr_t size)
414{
415    phys_addr_t end = base + size;
416    int i;
417
418    /* Walk through the array for collisions */
419    for (i = 0; i < type->cnt; i++) {
420        struct memblock_region *rgn = &type->regions[i];
421        phys_addr_t rend = rgn->base + rgn->size;
422
423        /* Nothing more to do, exit */
424        if (rgn->base > end || rgn->size == 0)
425            break;
426
427        /* If we fully enclose the block, drop it */
428        if (base <= rgn->base && end >= rend) {
429            memblock_remove_region(type, i--);
430            continue;
431        }
432
433        /* If we are fully enclosed within a block
434         * then we need to split it and we are done
435         */
436        if (base > rgn->base && end < rend) {
437            rgn->size = base - rgn->base;
438            if (!memblock_add_region(type, end, rend - end))
439                return 0;
440            /* Failure to split is bad, we at least
441             * restore the block before erroring
442             */
443            rgn->size = rend - rgn->base;
444            WARN_ON(1);
445            return -1;
446        }
447
448        /* Check if we need to trim the bottom of a block */
449        if (rgn->base < end && rend > end) {
450            rgn->size -= end - rgn->base;
451            rgn->base = end;
452            break;
453        }
454
455        /* And check if we need to trim the top of a block */
456        if (base < rend)
457            rgn->size -= rend - base;
458
459    }
460    return 0;
461}
462
463long __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)
464{
465    return __memblock_remove(&memblock.memory, base, size);
466}
467
468long __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
469{
470    return __memblock_remove(&memblock.reserved, base, size);
471}
472
473long __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
474{
475    struct memblock_type *_rgn = &memblock.reserved;
476
477    BUG_ON(0 == size);
478
479    return memblock_add_region(_rgn, base, size);
480}
481
482phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
483{
484    phys_addr_t found;
485
486    /* We align the size to limit fragmentation. Without this, a lot of
487     * small allocs quickly eat up the whole reserve array on sparc
488     */
489    size = memblock_align_up(size, align);
490
491    found = memblock_find_base(size, align, 0, max_addr);
492    if (found != MEMBLOCK_ERROR &&
493        !memblock_add_region(&memblock.reserved, found, size))
494        return found;
495
496    return 0;
497}
498
499phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
500{
501    phys_addr_t alloc;
502
503    alloc = __memblock_alloc_base(size, align, max_addr);
504
505    if (alloc == 0)
506        panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
507              (unsigned long long) size, (unsigned long long) max_addr);
508
509    return alloc;
510}
511
512phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
513{
514    return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
515}
516
517
518/*
519 * Additional node-local allocators. Search for node memory is bottom up
520 * and walks memblock regions within that node bottom-up as well, but allocation
521 * within an memblock region is top-down. XXX I plan to fix that at some stage
522 *
523 * WARNING: Only available after early_node_map[] has been populated,
524 * on some architectures, that is after all the calls to add_active_range()
525 * have been done to populate it.
526 */
527
528phys_addr_t __weak __init memblock_nid_range(phys_addr_t start, phys_addr_t end, int *nid)
529{
530#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
531    /*
532     * This code originates from sparc which really wants use to walk by addresses
533     * and returns the nid. This is not very convenient for early_pfn_map[] users
534     * as the map isn't sorted yet, and it really wants to be walked by nid.
535     *
536     * For now, I implement the inefficient method below which walks the early
537     * map multiple times. Eventually we may want to use an ARCH config option
538     * to implement a completely different method for both case.
539     */
540    unsigned long start_pfn, end_pfn;
541    int i;
542
543    for (i = 0; i < MAX_NUMNODES; i++) {
544        get_pfn_range_for_nid(i, &start_pfn, &end_pfn);
545        if (start < PFN_PHYS(start_pfn) || start >= PFN_PHYS(end_pfn))
546            continue;
547        *nid = i;
548        return min(end, PFN_PHYS(end_pfn));
549    }
550#endif
551    *nid = 0;
552
553    return end;
554}
555
556static phys_addr_t __init memblock_alloc_nid_region(struct memblock_region *mp,
557                           phys_addr_t size,
558                           phys_addr_t align, int nid)
559{
560    phys_addr_t start, end;
561
562    start = mp->base;
563    end = start + mp->size;
564
565    start = memblock_align_up(start, align);
566    while (start < end) {
567        phys_addr_t this_end;
568        int this_nid;
569
570        this_end = memblock_nid_range(start, end, &this_nid);
571        if (this_nid == nid) {
572            phys_addr_t ret = memblock_find_region(start, this_end, size, align);
573            if (ret != MEMBLOCK_ERROR &&
574                !memblock_add_region(&memblock.reserved, ret, size))
575                return ret;
576        }
577        start = this_end;
578    }
579
580    return MEMBLOCK_ERROR;
581}
582
583phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
584{
585    struct memblock_type *mem = &memblock.memory;
586    int i;
587
588    BUG_ON(0 == size);
589
590    /* We align the size to limit fragmentation. Without this, a lot of
591     * small allocs quickly eat up the whole reserve array on sparc
592     */
593    size = memblock_align_up(size, align);
594
595    /* We do a bottom-up search for a region with the right
596     * nid since that's easier considering how memblock_nid_range()
597     * works
598     */
599    for (i = 0; i < mem->cnt; i++) {
600        phys_addr_t ret = memblock_alloc_nid_region(&mem->regions[i],
601                           size, align, nid);
602        if (ret != MEMBLOCK_ERROR)
603            return ret;
604    }
605
606    return 0;
607}
608
609phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
610{
611    phys_addr_t res = memblock_alloc_nid(size, align, nid);
612
613    if (res)
614        return res;
615    return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
616}
617
618
619/*
620 * Remaining API functions
621 */
622
623/* You must call memblock_analyze() before this. */
624phys_addr_t __init memblock_phys_mem_size(void)
625{
626    return memblock.memory_size;
627}
628
629phys_addr_t __init_memblock memblock_end_of_DRAM(void)
630{
631    int idx = memblock.memory.cnt - 1;
632
633    return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
634}
635
636/* You must call memblock_analyze() after this. */
637void __init memblock_enforce_memory_limit(phys_addr_t memory_limit)
638{
639    unsigned long i;
640    phys_addr_t limit;
641    struct memblock_region *p;
642
643    if (!memory_limit)
644        return;
645
646    /* Truncate the memblock regions to satisfy the memory limit. */
647    limit = memory_limit;
648    for (i = 0; i < memblock.memory.cnt; i++) {
649        if (limit > memblock.memory.regions[i].size) {
650            limit -= memblock.memory.regions[i].size;
651            continue;
652        }
653
654        memblock.memory.regions[i].size = limit;
655        memblock.memory.cnt = i + 1;
656        break;
657    }
658
659    memory_limit = memblock_end_of_DRAM();
660
661    /* And truncate any reserves above the limit also. */
662    for (i = 0; i < memblock.reserved.cnt; i++) {
663        p = &memblock.reserved.regions[i];
664
665        if (p->base > memory_limit)
666            p->size = 0;
667        else if ((p->base + p->size) > memory_limit)
668            p->size = memory_limit - p->base;
669
670        if (p->size == 0) {
671            memblock_remove_region(&memblock.reserved, i);
672            i--;
673        }
674    }
675}
676
677static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)
678{
679    unsigned int left = 0, right = type->cnt;
680
681    do {
682        unsigned int mid = (right + left) / 2;
683
684        if (addr < type->regions[mid].base)
685            right = mid;
686        else if (addr >= (type->regions[mid].base +
687                  type->regions[mid].size))
688            left = mid + 1;
689        else
690            return mid;
691    } while (left < right);
692    return -1;
693}
694
695int __init memblock_is_reserved(phys_addr_t addr)
696{
697    return memblock_search(&memblock.reserved, addr) != -1;
698}
699
700int __init_memblock memblock_is_memory(phys_addr_t addr)
701{
702    return memblock_search(&memblock.memory, addr) != -1;
703}
704
705int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
706{
707    int idx = memblock_search(&memblock.memory, base);
708
709    if (idx == -1)
710        return 0;
711    return memblock.memory.regions[idx].base <= base &&
712        (memblock.memory.regions[idx].base +
713         memblock.memory.regions[idx].size) >= (base + size);
714}
715
716int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
717{
718    return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
719}
720
721
722void __init_memblock memblock_set_current_limit(phys_addr_t limit)
723{
724    memblock.current_limit = limit;
725}
726
727static void __init_memblock memblock_dump(struct memblock_type *region, char *name)
728{
729    unsigned long long base, size;
730    int i;
731
732    pr_info(" %s.cnt = 0x%lx\n", name, region->cnt);
733
734    for (i = 0; i < region->cnt; i++) {
735        base = region->regions[i].base;
736        size = region->regions[i].size;
737
738        pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes\n",
739            name, i, base, base + size - 1, size);
740    }
741}
742
743void __init_memblock memblock_dump_all(void)
744{
745    if (!memblock_debug)
746        return;
747
748    pr_info("MEMBLOCK configuration:\n");
749    pr_info(" memory size = 0x%llx\n", (unsigned long long)memblock.memory_size);
750
751    memblock_dump(&memblock.memory, "memory");
752    memblock_dump(&memblock.reserved, "reserved");
753}
754
755void __init memblock_analyze(void)
756{
757    int i;
758
759    /* Check marker in the unused last array entry */
760    WARN_ON(memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS].base
761        != (phys_addr_t)RED_INACTIVE);
762    WARN_ON(memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS].base
763        != (phys_addr_t)RED_INACTIVE);
764
765    memblock.memory_size = 0;
766
767    for (i = 0; i < memblock.memory.cnt; i++)
768        memblock.memory_size += memblock.memory.regions[i].size;
769
770    /* We allow resizing from there */
771    memblock_can_resize = 1;
772}
773
774void __init memblock_init(void)
775{
776    static int init_done __initdata = 0;
777
778    if (init_done)
779        return;
780    init_done = 1;
781
782    /* Hookup the initial arrays */
783    memblock.memory.regions = memblock_memory_init_regions;
784    memblock.memory.max = INIT_MEMBLOCK_REGIONS;
785    memblock.reserved.regions = memblock_reserved_init_regions;
786    memblock.reserved.max = INIT_MEMBLOCK_REGIONS;
787
788    /* Write a marker in the unused last array entry */
789    memblock.memory.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
790    memblock.reserved.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
791
792    /* Create a dummy zero size MEMBLOCK which will get coalesced away later.
793     * This simplifies the memblock_add() code below...
794     */
795    memblock.memory.regions[0].base = 0;
796    memblock.memory.regions[0].size = 0;
797    memblock.memory.cnt = 1;
798
799    /* Ditto. */
800    memblock.reserved.regions[0].base = 0;
801    memblock.reserved.regions[0].size = 0;
802    memblock.reserved.cnt = 1;
803
804    memblock.current_limit = MEMBLOCK_ALLOC_ANYWHERE;
805}
806
807static int __init early_memblock(char *p)
808{
809    if (p && strstr(p, "debug"))
810        memblock_debug = 1;
811    return 0;
812}
813early_param("memblock", early_memblock);
814
815#if defined(CONFIG_DEBUG_FS) && !defined(ARCH_DISCARD_MEMBLOCK)
816
817static int memblock_debug_show(struct seq_file *m, void *private)
818{
819    struct memblock_type *type = m->private;
820    struct memblock_region *reg;
821    int i;
822
823    for (i = 0; i < type->cnt; i++) {
824        reg = &type->regions[i];
825        seq_printf(m, "%4d: ", i);
826        if (sizeof(phys_addr_t) == 4)
827            seq_printf(m, "0x%08lx..0x%08lx\n",
828                   (unsigned long)reg->base,
829                   (unsigned long)(reg->base + reg->size - 1));
830        else
831            seq_printf(m, "0x%016llx..0x%016llx\n",
832                   (unsigned long long)reg->base,
833                   (unsigned long long)(reg->base + reg->size - 1));
834
835    }
836    return 0;
837}
838
839static int memblock_debug_open(struct inode *inode, struct file *file)
840{
841    return single_open(file, memblock_debug_show, inode->i_private);
842}
843
844static const struct file_operations memblock_debug_fops = {
845    .open = memblock_debug_open,
846    .read = seq_read,
847    .llseek = seq_lseek,
848    .release = single_release,
849};
850
851static int __init memblock_init_debugfs(void)
852{
853    struct dentry *root = debugfs_create_dir("memblock", NULL);
854    if (!root)
855        return -ENXIO;
856    debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
857    debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
858
859    return 0;
860}
861__initcall(memblock_init_debugfs);
862
863#endif /* CONFIG_DEBUG_FS */
864

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