2 * Procedures for maintaining information about logical memory blocks.
4 * Peter Bergner, IBM Corp. June 2001.
5 * Copyright (C) 2001 Peter Bergner.
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.
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/bitops.h>
16 #include <linux/poison.h>
17 #include <linux/memblock.h>
19 struct memblock memblock;
21 static int memblock_debug;
22 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS + 1];
23 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS + 1];
25 static int __init early_memblock(char *p)
27 if (p && strstr(p, "debug"))
31 early_param("memblock", early_memblock);
33 static void memblock_dump(struct memblock_type *region, char *name)
35 unsigned long long base, size;
38 pr_info(" %s.cnt = 0x%lx\n", name, region->cnt);
40 for (i = 0; i < region->cnt; i++) {
41 base = region->regions[i].base;
42 size = region->regions[i].size;
44 pr_info(" %s[0x%x]\t0x%016llx - 0x%016llx, 0x%llx bytes\n",
45 name, i, base, base + size - 1, size);
49 void memblock_dump_all(void)
54 pr_info("MEMBLOCK configuration:\n");
55 pr_info(" memory size = 0x%llx\n", (unsigned long long)memblock.memory_size);
57 memblock_dump(&memblock.memory, "memory");
58 memblock_dump(&memblock.reserved, "reserved");
61 static unsigned long memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
62 phys_addr_t base2, phys_addr_t size2)
64 return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
67 static long memblock_addrs_adjacent(phys_addr_t base1, phys_addr_t size1,
68 phys_addr_t base2, phys_addr_t size2)
70 if (base2 == base1 + size1)
72 else if (base1 == base2 + size2)
78 static long memblock_regions_adjacent(struct memblock_type *type,
79 unsigned long r1, unsigned long r2)
81 phys_addr_t base1 = type->regions[r1].base;
82 phys_addr_t size1 = type->regions[r1].size;
83 phys_addr_t base2 = type->regions[r2].base;
84 phys_addr_t size2 = type->regions[r2].size;
86 return memblock_addrs_adjacent(base1, size1, base2, size2);
89 static void memblock_remove_region(struct memblock_type *type, unsigned long r)
93 for (i = r; i < type->cnt - 1; i++) {
94 type->regions[i].base = type->regions[i + 1].base;
95 type->regions[i].size = type->regions[i + 1].size;
100 /* Assumption: base addr of region 1 < base addr of region 2 */
101 static void memblock_coalesce_regions(struct memblock_type *type,
102 unsigned long r1, unsigned long r2)
104 type->regions[r1].size += type->regions[r2].size;
105 memblock_remove_region(type, r2);
108 void __init memblock_init(void)
110 /* Hookup the initial arrays */
111 memblock.memory.regions = memblock_memory_init_regions;
112 memblock.memory.max = INIT_MEMBLOCK_REGIONS;
113 memblock.reserved.regions = memblock_reserved_init_regions;
114 memblock.reserved.max = INIT_MEMBLOCK_REGIONS;
116 /* Write a marker in the unused last array entry */
117 memblock.memory.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
118 memblock.reserved.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
120 /* Create a dummy zero size MEMBLOCK which will get coalesced away later.
121 * This simplifies the memblock_add() code below...
123 memblock.memory.regions[0].base = 0;
124 memblock.memory.regions[0].size = 0;
125 memblock.memory.cnt = 1;
128 memblock.reserved.regions[0].base = 0;
129 memblock.reserved.regions[0].size = 0;
130 memblock.reserved.cnt = 1;
132 memblock.current_limit = MEMBLOCK_ALLOC_ANYWHERE;
135 void __init memblock_analyze(void)
139 /* Check marker in the unused last array entry */
140 WARN_ON(memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS].base
141 != (phys_addr_t)RED_INACTIVE);
142 WARN_ON(memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS].base
143 != (phys_addr_t)RED_INACTIVE);
145 memblock.memory_size = 0;
147 for (i = 0; i < memblock.memory.cnt; i++)
148 memblock.memory_size += memblock.memory.regions[i].size;
151 static long memblock_add_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
153 unsigned long coalesced = 0;
156 if ((type->cnt == 1) && (type->regions[0].size == 0)) {
157 type->regions[0].base = base;
158 type->regions[0].size = size;
162 /* First try and coalesce this MEMBLOCK with another. */
163 for (i = 0; i < type->cnt; i++) {
164 phys_addr_t rgnbase = type->regions[i].base;
165 phys_addr_t rgnsize = type->regions[i].size;
167 if ((rgnbase == base) && (rgnsize == size))
168 /* Already have this region, so we're done */
171 adjacent = memblock_addrs_adjacent(base, size, rgnbase, rgnsize);
173 type->regions[i].base -= size;
174 type->regions[i].size += size;
177 } else if (adjacent < 0) {
178 type->regions[i].size += size;
184 if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1)) {
185 memblock_coalesce_regions(type, i, i+1);
191 if (type->cnt >= type->max)
194 /* Couldn't coalesce the MEMBLOCK, so add it to the sorted table. */
195 for (i = type->cnt - 1; i >= 0; i--) {
196 if (base < type->regions[i].base) {
197 type->regions[i+1].base = type->regions[i].base;
198 type->regions[i+1].size = type->regions[i].size;
200 type->regions[i+1].base = base;
201 type->regions[i+1].size = size;
206 if (base < type->regions[0].base) {
207 type->regions[0].base = base;
208 type->regions[0].size = size;
215 long memblock_add(phys_addr_t base, phys_addr_t size)
217 return memblock_add_region(&memblock.memory, base, size);
221 static long __memblock_remove(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
223 phys_addr_t rgnbegin, rgnend;
224 phys_addr_t end = base + size;
227 rgnbegin = rgnend = 0; /* supress gcc warnings */
229 /* Find the region where (base, size) belongs to */
230 for (i=0; i < type->cnt; i++) {
231 rgnbegin = type->regions[i].base;
232 rgnend = rgnbegin + type->regions[i].size;
234 if ((rgnbegin <= base) && (end <= rgnend))
238 /* Didn't find the region */
242 /* Check to see if we are removing entire region */
243 if ((rgnbegin == base) && (rgnend == end)) {
244 memblock_remove_region(type, i);
248 /* Check to see if region is matching at the front */
249 if (rgnbegin == base) {
250 type->regions[i].base = end;
251 type->regions[i].size -= size;
255 /* Check to see if the region is matching at the end */
257 type->regions[i].size -= size;
262 * We need to split the entry - adjust the current one to the
263 * beginging of the hole and add the region after hole.
265 type->regions[i].size = base - type->regions[i].base;
266 return memblock_add_region(type, end, rgnend - end);
269 long memblock_remove(phys_addr_t base, phys_addr_t size)
271 return __memblock_remove(&memblock.memory, base, size);
274 long __init memblock_free(phys_addr_t base, phys_addr_t size)
276 return __memblock_remove(&memblock.reserved, base, size);
279 long __init memblock_reserve(phys_addr_t base, phys_addr_t size)
281 struct memblock_type *_rgn = &memblock.reserved;
285 return memblock_add_region(_rgn, base, size);
288 long memblock_overlaps_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
292 for (i = 0; i < type->cnt; i++) {
293 phys_addr_t rgnbase = type->regions[i].base;
294 phys_addr_t rgnsize = type->regions[i].size;
295 if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
299 return (i < type->cnt) ? i : -1;
302 static phys_addr_t memblock_align_down(phys_addr_t addr, phys_addr_t size)
304 return addr & ~(size - 1);
307 static phys_addr_t memblock_align_up(phys_addr_t addr, phys_addr_t size)
309 return (addr + (size - 1)) & ~(size - 1);
312 static phys_addr_t __init memblock_find_region(phys_addr_t start, phys_addr_t end,
313 phys_addr_t size, phys_addr_t align)
315 phys_addr_t base, res_base;
318 base = memblock_align_down((end - size), align);
319 while (start <= base) {
320 j = memblock_overlaps_region(&memblock.reserved, base, size);
323 res_base = memblock.reserved.regions[j].base;
326 base = memblock_align_down(res_base - size, align);
329 return ~(phys_addr_t)0;
332 phys_addr_t __weak __init memblock_nid_range(phys_addr_t start, phys_addr_t end, int *nid)
339 static phys_addr_t __init memblock_alloc_nid_region(struct memblock_region *mp,
341 phys_addr_t align, int nid)
343 phys_addr_t start, end;
346 end = start + mp->size;
348 start = memblock_align_up(start, align);
349 while (start < end) {
350 phys_addr_t this_end;
353 this_end = memblock_nid_range(start, end, &this_nid);
354 if (this_nid == nid) {
355 phys_addr_t ret = memblock_find_region(start, this_end, size, align);
356 if (ret != ~(phys_addr_t)0 &&
357 memblock_add_region(&memblock.reserved, ret, size) >= 0)
363 return ~(phys_addr_t)0;
366 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
368 struct memblock_type *mem = &memblock.memory;
373 /* We do a bottom-up search for a region with the right
374 * nid since that's easier considering how memblock_nid_range()
377 size = memblock_align_up(size, align);
379 for (i = 0; i < mem->cnt; i++) {
380 phys_addr_t ret = memblock_alloc_nid_region(&mem->regions[i],
382 if (ret != ~(phys_addr_t)0)
386 return memblock_alloc(size, align);
389 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
391 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
394 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
398 alloc = __memblock_alloc_base(size, align, max_addr);
401 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
402 (unsigned long long) size, (unsigned long long) max_addr);
407 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
410 phys_addr_t base = 0;
411 phys_addr_t res_base;
415 size = memblock_align_up(size, align);
417 /* Pump up max_addr */
418 if (max_addr == MEMBLOCK_ALLOC_ACCESSIBLE)
419 max_addr = memblock.current_limit;
421 /* We do a top-down search, this tends to limit memory
422 * fragmentation by keeping early boot allocs near the
425 for (i = memblock.memory.cnt - 1; i >= 0; i--) {
426 phys_addr_t memblockbase = memblock.memory.regions[i].base;
427 phys_addr_t memblocksize = memblock.memory.regions[i].size;
429 if (memblocksize < size)
431 base = min(memblockbase + memblocksize, max_addr);
432 res_base = memblock_find_region(memblockbase, base, size, align);
433 if (res_base != ~(phys_addr_t)0 &&
434 memblock_add_region(&memblock.reserved, res_base, size) >= 0)
440 /* You must call memblock_analyze() before this. */
441 phys_addr_t __init memblock_phys_mem_size(void)
443 return memblock.memory_size;
446 phys_addr_t memblock_end_of_DRAM(void)
448 int idx = memblock.memory.cnt - 1;
450 return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
453 /* You must call memblock_analyze() after this. */
454 void __init memblock_enforce_memory_limit(phys_addr_t memory_limit)
458 struct memblock_region *p;
463 /* Truncate the memblock regions to satisfy the memory limit. */
464 limit = memory_limit;
465 for (i = 0; i < memblock.memory.cnt; i++) {
466 if (limit > memblock.memory.regions[i].size) {
467 limit -= memblock.memory.regions[i].size;
471 memblock.memory.regions[i].size = limit;
472 memblock.memory.cnt = i + 1;
476 memory_limit = memblock_end_of_DRAM();
478 /* And truncate any reserves above the limit also. */
479 for (i = 0; i < memblock.reserved.cnt; i++) {
480 p = &memblock.reserved.regions[i];
482 if (p->base > memory_limit)
484 else if ((p->base + p->size) > memory_limit)
485 p->size = memory_limit - p->base;
488 memblock_remove_region(&memblock.reserved, i);
494 static int memblock_search(struct memblock_type *type, phys_addr_t addr)
496 unsigned int left = 0, right = type->cnt;
499 unsigned int mid = (right + left) / 2;
501 if (addr < type->regions[mid].base)
503 else if (addr >= (type->regions[mid].base +
504 type->regions[mid].size))
508 } while (left < right);
512 int __init memblock_is_reserved(phys_addr_t addr)
514 return memblock_search(&memblock.reserved, addr) != -1;
517 int memblock_is_memory(phys_addr_t addr)
519 return memblock_search(&memblock.memory, addr) != -1;
522 int memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
524 int idx = memblock_search(&memblock.reserved, base);
528 return memblock.reserved.regions[idx].base <= base &&
529 (memblock.reserved.regions[idx].base +
530 memblock.reserved.regions[idx].size) >= (base + size);
533 int memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
535 return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
539 void __init memblock_set_current_limit(phys_addr_t limit)
541 memblock.current_limit = limit;