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 #define MEMBLOCK_ERROR (~(phys_addr_t)0)
27 static int __init early_memblock(char *p)
29 if (p && strstr(p, "debug"))
33 early_param("memblock", early_memblock);
35 static void memblock_dump(struct memblock_type *region, char *name)
37 unsigned long long base, size;
40 pr_info(" %s.cnt = 0x%lx\n", name, region->cnt);
42 for (i = 0; i < region->cnt; i++) {
43 base = region->regions[i].base;
44 size = region->regions[i].size;
46 pr_info(" %s[0x%x]\t0x%016llx - 0x%016llx, 0x%llx bytes\n",
47 name, i, base, base + size - 1, size);
51 void memblock_dump_all(void)
56 pr_info("MEMBLOCK configuration:\n");
57 pr_info(" memory size = 0x%llx\n", (unsigned long long)memblock.memory_size);
59 memblock_dump(&memblock.memory, "memory");
60 memblock_dump(&memblock.reserved, "reserved");
63 static unsigned long memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,
64 phys_addr_t base2, phys_addr_t size2)
66 return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
69 static long memblock_addrs_adjacent(phys_addr_t base1, phys_addr_t size1,
70 phys_addr_t base2, phys_addr_t size2)
72 if (base2 == base1 + size1)
74 else if (base1 == base2 + size2)
80 static long memblock_regions_adjacent(struct memblock_type *type,
81 unsigned long r1, unsigned long r2)
83 phys_addr_t base1 = type->regions[r1].base;
84 phys_addr_t size1 = type->regions[r1].size;
85 phys_addr_t base2 = type->regions[r2].base;
86 phys_addr_t size2 = type->regions[r2].size;
88 return memblock_addrs_adjacent(base1, size1, base2, size2);
91 static void memblock_remove_region(struct memblock_type *type, unsigned long r)
95 for (i = r; i < type->cnt - 1; i++) {
96 type->regions[i].base = type->regions[i + 1].base;
97 type->regions[i].size = type->regions[i + 1].size;
102 /* Assumption: base addr of region 1 < base addr of region 2 */
103 static void memblock_coalesce_regions(struct memblock_type *type,
104 unsigned long r1, unsigned long r2)
106 type->regions[r1].size += type->regions[r2].size;
107 memblock_remove_region(type, r2);
110 void __init memblock_init(void)
112 /* Hookup the initial arrays */
113 memblock.memory.regions = memblock_memory_init_regions;
114 memblock.memory.max = INIT_MEMBLOCK_REGIONS;
115 memblock.reserved.regions = memblock_reserved_init_regions;
116 memblock.reserved.max = INIT_MEMBLOCK_REGIONS;
118 /* Write a marker in the unused last array entry */
119 memblock.memory.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
120 memblock.reserved.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
122 /* Create a dummy zero size MEMBLOCK which will get coalesced away later.
123 * This simplifies the memblock_add() code below...
125 memblock.memory.regions[0].base = 0;
126 memblock.memory.regions[0].size = 0;
127 memblock.memory.cnt = 1;
130 memblock.reserved.regions[0].base = 0;
131 memblock.reserved.regions[0].size = 0;
132 memblock.reserved.cnt = 1;
134 memblock.current_limit = MEMBLOCK_ALLOC_ANYWHERE;
137 void __init memblock_analyze(void)
141 /* Check marker in the unused last array entry */
142 WARN_ON(memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS].base
143 != (phys_addr_t)RED_INACTIVE);
144 WARN_ON(memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS].base
145 != (phys_addr_t)RED_INACTIVE);
147 memblock.memory_size = 0;
149 for (i = 0; i < memblock.memory.cnt; i++)
150 memblock.memory_size += memblock.memory.regions[i].size;
153 static long memblock_add_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
155 unsigned long coalesced = 0;
158 if ((type->cnt == 1) && (type->regions[0].size == 0)) {
159 type->regions[0].base = base;
160 type->regions[0].size = size;
164 /* First try and coalesce this MEMBLOCK with another. */
165 for (i = 0; i < type->cnt; i++) {
166 phys_addr_t rgnbase = type->regions[i].base;
167 phys_addr_t rgnsize = type->regions[i].size;
169 if ((rgnbase == base) && (rgnsize == size))
170 /* Already have this region, so we're done */
173 adjacent = memblock_addrs_adjacent(base, size, rgnbase, rgnsize);
175 type->regions[i].base -= size;
176 type->regions[i].size += size;
179 } else if (adjacent < 0) {
180 type->regions[i].size += size;
186 if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1)) {
187 memblock_coalesce_regions(type, i, i+1);
193 if (type->cnt >= type->max)
196 /* Couldn't coalesce the MEMBLOCK, so add it to the sorted table. */
197 for (i = type->cnt - 1; i >= 0; i--) {
198 if (base < type->regions[i].base) {
199 type->regions[i+1].base = type->regions[i].base;
200 type->regions[i+1].size = type->regions[i].size;
202 type->regions[i+1].base = base;
203 type->regions[i+1].size = size;
208 if (base < type->regions[0].base) {
209 type->regions[0].base = base;
210 type->regions[0].size = size;
217 long memblock_add(phys_addr_t base, phys_addr_t size)
219 return memblock_add_region(&memblock.memory, base, size);
223 static long __memblock_remove(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
225 phys_addr_t rgnbegin, rgnend;
226 phys_addr_t end = base + size;
229 rgnbegin = rgnend = 0; /* supress gcc warnings */
231 /* Find the region where (base, size) belongs to */
232 for (i=0; i < type->cnt; i++) {
233 rgnbegin = type->regions[i].base;
234 rgnend = rgnbegin + type->regions[i].size;
236 if ((rgnbegin <= base) && (end <= rgnend))
240 /* Didn't find the region */
244 /* Check to see if we are removing entire region */
245 if ((rgnbegin == base) && (rgnend == end)) {
246 memblock_remove_region(type, i);
250 /* Check to see if region is matching at the front */
251 if (rgnbegin == base) {
252 type->regions[i].base = end;
253 type->regions[i].size -= size;
257 /* Check to see if the region is matching at the end */
259 type->regions[i].size -= size;
264 * We need to split the entry - adjust the current one to the
265 * beginging of the hole and add the region after hole.
267 type->regions[i].size = base - type->regions[i].base;
268 return memblock_add_region(type, end, rgnend - end);
271 long memblock_remove(phys_addr_t base, phys_addr_t size)
273 return __memblock_remove(&memblock.memory, base, size);
276 long __init memblock_free(phys_addr_t base, phys_addr_t size)
278 return __memblock_remove(&memblock.reserved, base, size);
281 long __init memblock_reserve(phys_addr_t base, phys_addr_t size)
283 struct memblock_type *_rgn = &memblock.reserved;
287 return memblock_add_region(_rgn, base, size);
290 long memblock_overlaps_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size)
294 for (i = 0; i < type->cnt; i++) {
295 phys_addr_t rgnbase = type->regions[i].base;
296 phys_addr_t rgnsize = type->regions[i].size;
297 if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
301 return (i < type->cnt) ? i : -1;
304 static phys_addr_t memblock_align_down(phys_addr_t addr, phys_addr_t size)
306 return addr & ~(size - 1);
309 static phys_addr_t memblock_align_up(phys_addr_t addr, phys_addr_t size)
311 return (addr + (size - 1)) & ~(size - 1);
314 static phys_addr_t __init memblock_find_region(phys_addr_t start, phys_addr_t end,
315 phys_addr_t size, phys_addr_t align)
317 phys_addr_t base, res_base;
320 base = memblock_align_down((end - size), align);
321 while (start <= base) {
322 j = memblock_overlaps_region(&memblock.reserved, base, size);
325 res_base = memblock.reserved.regions[j].base;
328 base = memblock_align_down(res_base - size, align);
331 return MEMBLOCK_ERROR;
334 phys_addr_t __weak __init memblock_nid_range(phys_addr_t start, phys_addr_t end, int *nid)
341 static phys_addr_t __init memblock_alloc_nid_region(struct memblock_region *mp,
343 phys_addr_t align, int nid)
345 phys_addr_t start, end;
348 end = start + mp->size;
350 start = memblock_align_up(start, align);
351 while (start < end) {
352 phys_addr_t this_end;
355 this_end = memblock_nid_range(start, end, &this_nid);
356 if (this_nid == nid) {
357 phys_addr_t ret = memblock_find_region(start, this_end, size, align);
358 if (ret != MEMBLOCK_ERROR &&
359 memblock_add_region(&memblock.reserved, ret, size) >= 0)
365 return MEMBLOCK_ERROR;
368 phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
370 struct memblock_type *mem = &memblock.memory;
375 /* We do a bottom-up search for a region with the right
376 * nid since that's easier considering how memblock_nid_range()
379 size = memblock_align_up(size, align);
381 for (i = 0; i < mem->cnt; i++) {
382 phys_addr_t ret = memblock_alloc_nid_region(&mem->regions[i],
384 if (ret != MEMBLOCK_ERROR)
388 return memblock_alloc(size, align);
391 phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
393 return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
396 phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
400 alloc = __memblock_alloc_base(size, align, max_addr);
403 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
404 (unsigned long long) size, (unsigned long long) max_addr);
409 phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
412 phys_addr_t base = 0;
413 phys_addr_t res_base;
417 size = memblock_align_up(size, align);
419 /* Pump up max_addr */
420 if (max_addr == MEMBLOCK_ALLOC_ACCESSIBLE)
421 max_addr = memblock.current_limit;
423 /* We do a top-down search, this tends to limit memory
424 * fragmentation by keeping early boot allocs near the
427 for (i = memblock.memory.cnt - 1; i >= 0; i--) {
428 phys_addr_t memblockbase = memblock.memory.regions[i].base;
429 phys_addr_t memblocksize = memblock.memory.regions[i].size;
431 if (memblocksize < size)
433 base = min(memblockbase + memblocksize, max_addr);
434 res_base = memblock_find_region(memblockbase, base, size, align);
435 if (res_base != MEMBLOCK_ERROR &&
436 memblock_add_region(&memblock.reserved, res_base, size) >= 0)
442 /* You must call memblock_analyze() before this. */
443 phys_addr_t __init memblock_phys_mem_size(void)
445 return memblock.memory_size;
448 phys_addr_t memblock_end_of_DRAM(void)
450 int idx = memblock.memory.cnt - 1;
452 return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);
455 /* You must call memblock_analyze() after this. */
456 void __init memblock_enforce_memory_limit(phys_addr_t memory_limit)
460 struct memblock_region *p;
465 /* Truncate the memblock regions to satisfy the memory limit. */
466 limit = memory_limit;
467 for (i = 0; i < memblock.memory.cnt; i++) {
468 if (limit > memblock.memory.regions[i].size) {
469 limit -= memblock.memory.regions[i].size;
473 memblock.memory.regions[i].size = limit;
474 memblock.memory.cnt = i + 1;
478 memory_limit = memblock_end_of_DRAM();
480 /* And truncate any reserves above the limit also. */
481 for (i = 0; i < memblock.reserved.cnt; i++) {
482 p = &memblock.reserved.regions[i];
484 if (p->base > memory_limit)
486 else if ((p->base + p->size) > memory_limit)
487 p->size = memory_limit - p->base;
490 memblock_remove_region(&memblock.reserved, i);
496 static int memblock_search(struct memblock_type *type, phys_addr_t addr)
498 unsigned int left = 0, right = type->cnt;
501 unsigned int mid = (right + left) / 2;
503 if (addr < type->regions[mid].base)
505 else if (addr >= (type->regions[mid].base +
506 type->regions[mid].size))
510 } while (left < right);
514 int __init memblock_is_reserved(phys_addr_t addr)
516 return memblock_search(&memblock.reserved, addr) != -1;
519 int memblock_is_memory(phys_addr_t addr)
521 return memblock_search(&memblock.memory, addr) != -1;
524 int memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
526 int idx = memblock_search(&memblock.reserved, base);
530 return memblock.reserved.regions[idx].base <= base &&
531 (memblock.reserved.regions[idx].base +
532 memblock.reserved.regions[idx].size) >= (base + size);
535 int memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
537 return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;
541 void __init memblock_set_current_limit(phys_addr_t limit)
543 memblock.current_limit = limit;