]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/mm/bootmem.c | |
3 | * | |
4 | * Copyright (C) 1999 Ingo Molnar | |
5 | * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999 | |
6 | * | |
7 | * simple boot-time physical memory area allocator and | |
8 | * free memory collector. It's used to deal with reserved | |
9 | * system memory and memory holes as well. | |
10 | */ | |
11 | ||
12 | #include <linux/mm.h> | |
13 | #include <linux/kernel_stat.h> | |
14 | #include <linux/swap.h> | |
15 | #include <linux/interrupt.h> | |
16 | #include <linux/init.h> | |
17 | #include <linux/bootmem.h> | |
18 | #include <linux/mmzone.h> | |
19 | #include <linux/module.h> | |
20 | #include <asm/dma.h> | |
21 | #include <asm/io.h> | |
22 | #include "internal.h" | |
23 | ||
24 | /* | |
25 | * Access to this subsystem has to be serialized externally. (this is | |
26 | * true for the boot process anyway) | |
27 | */ | |
28 | unsigned long max_low_pfn; | |
29 | unsigned long min_low_pfn; | |
30 | unsigned long max_pfn; | |
31 | ||
32 | EXPORT_SYMBOL(max_pfn); /* This is exported so | |
33 | * dma_get_required_mask(), which uses | |
34 | * it, can be an inline function */ | |
35 | ||
679bc9fb | 36 | static LIST_HEAD(bdata_list); |
92aa63a5 VG |
37 | #ifdef CONFIG_CRASH_DUMP |
38 | /* | |
39 | * If we have booted due to a crash, max_pfn will be a very low value. We need | |
40 | * to know the amount of memory that the previous kernel used. | |
41 | */ | |
42 | unsigned long saved_max_pfn; | |
43 | #endif | |
44 | ||
1da177e4 LT |
45 | /* return the number of _pages_ that will be allocated for the boot bitmap */ |
46 | unsigned long __init bootmem_bootmap_pages (unsigned long pages) | |
47 | { | |
48 | unsigned long mapsize; | |
49 | ||
50 | mapsize = (pages+7)/8; | |
51 | mapsize = (mapsize + ~PAGE_MASK) & PAGE_MASK; | |
52 | mapsize >>= PAGE_SHIFT; | |
53 | ||
54 | return mapsize; | |
55 | } | |
679bc9fb KH |
56 | /* |
57 | * link bdata in order | |
58 | */ | |
59 | static void link_bootmem(bootmem_data_t *bdata) | |
60 | { | |
61 | bootmem_data_t *ent; | |
62 | if (list_empty(&bdata_list)) { | |
63 | list_add(&bdata->list, &bdata_list); | |
64 | return; | |
65 | } | |
66 | /* insert in order */ | |
67 | list_for_each_entry(ent, &bdata_list, list) { | |
68 | if (bdata->node_boot_start < ent->node_boot_start) { | |
69 | list_add_tail(&bdata->list, &ent->list); | |
70 | return; | |
71 | } | |
72 | } | |
73 | list_add_tail(&bdata->list, &bdata_list); | |
74 | return; | |
75 | } | |
76 | ||
1da177e4 LT |
77 | |
78 | /* | |
79 | * Called once to set up the allocator itself. | |
80 | */ | |
81 | static unsigned long __init init_bootmem_core (pg_data_t *pgdat, | |
82 | unsigned long mapstart, unsigned long start, unsigned long end) | |
83 | { | |
84 | bootmem_data_t *bdata = pgdat->bdata; | |
85 | unsigned long mapsize = ((end - start)+7)/8; | |
86 | ||
8c0e33c1 | 87 | mapsize = ALIGN(mapsize, sizeof(long)); |
1da177e4 LT |
88 | bdata->node_bootmem_map = phys_to_virt(mapstart << PAGE_SHIFT); |
89 | bdata->node_boot_start = (start << PAGE_SHIFT); | |
90 | bdata->node_low_pfn = end; | |
679bc9fb | 91 | link_bootmem(bdata); |
1da177e4 LT |
92 | |
93 | /* | |
94 | * Initially all pages are reserved - setup_arch() has to | |
95 | * register free RAM areas explicitly. | |
96 | */ | |
97 | memset(bdata->node_bootmem_map, 0xff, mapsize); | |
98 | ||
99 | return mapsize; | |
100 | } | |
101 | ||
102 | /* | |
103 | * Marks a particular physical memory range as unallocatable. Usable RAM | |
104 | * might be used for boot-time allocations - or it might get added | |
105 | * to the free page pool later on. | |
106 | */ | |
107 | static void __init reserve_bootmem_core(bootmem_data_t *bdata, unsigned long addr, unsigned long size) | |
108 | { | |
109 | unsigned long i; | |
110 | /* | |
111 | * round up, partially reserved pages are considered | |
112 | * fully reserved. | |
113 | */ | |
114 | unsigned long sidx = (addr - bdata->node_boot_start)/PAGE_SIZE; | |
115 | unsigned long eidx = (addr + size - bdata->node_boot_start + | |
116 | PAGE_SIZE-1)/PAGE_SIZE; | |
117 | unsigned long end = (addr + size + PAGE_SIZE-1)/PAGE_SIZE; | |
118 | ||
119 | BUG_ON(!size); | |
120 | BUG_ON(sidx >= eidx); | |
121 | BUG_ON((addr >> PAGE_SHIFT) >= bdata->node_low_pfn); | |
122 | BUG_ON(end > bdata->node_low_pfn); | |
123 | ||
124 | for (i = sidx; i < eidx; i++) | |
125 | if (test_and_set_bit(i, bdata->node_bootmem_map)) { | |
126 | #ifdef CONFIG_DEBUG_BOOTMEM | |
127 | printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE); | |
128 | #endif | |
129 | } | |
130 | } | |
131 | ||
132 | static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr, unsigned long size) | |
133 | { | |
134 | unsigned long i; | |
135 | unsigned long start; | |
136 | /* | |
137 | * round down end of usable mem, partially free pages are | |
138 | * considered reserved. | |
139 | */ | |
140 | unsigned long sidx; | |
141 | unsigned long eidx = (addr + size - bdata->node_boot_start)/PAGE_SIZE; | |
142 | unsigned long end = (addr + size)/PAGE_SIZE; | |
143 | ||
144 | BUG_ON(!size); | |
145 | BUG_ON(end > bdata->node_low_pfn); | |
146 | ||
147 | if (addr < bdata->last_success) | |
148 | bdata->last_success = addr; | |
149 | ||
150 | /* | |
151 | * Round up the beginning of the address. | |
152 | */ | |
153 | start = (addr + PAGE_SIZE-1) / PAGE_SIZE; | |
154 | sidx = start - (bdata->node_boot_start/PAGE_SIZE); | |
155 | ||
156 | for (i = sidx; i < eidx; i++) { | |
157 | if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map))) | |
158 | BUG(); | |
159 | } | |
160 | } | |
161 | ||
162 | /* | |
163 | * We 'merge' subsequent allocations to save space. We might 'lose' | |
164 | * some fraction of a page if allocations cannot be satisfied due to | |
165 | * size constraints on boxes where there is physical RAM space | |
166 | * fragmentation - in these cases (mostly large memory boxes) this | |
167 | * is not a problem. | |
168 | * | |
169 | * On low memory boxes we get it right in 100% of the cases. | |
170 | * | |
171 | * alignment has to be a power of 2 value. | |
172 | * | |
173 | * NOTE: This function is _not_ reentrant. | |
174 | */ | |
267b4801 | 175 | void * __init |
1da177e4 | 176 | __alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size, |
281dd25c | 177 | unsigned long align, unsigned long goal, unsigned long limit) |
1da177e4 LT |
178 | { |
179 | unsigned long offset, remaining_size, areasize, preferred; | |
281dd25c | 180 | unsigned long i, start = 0, incr, eidx, end_pfn = bdata->node_low_pfn; |
1da177e4 LT |
181 | void *ret; |
182 | ||
183 | if(!size) { | |
184 | printk("__alloc_bootmem_core(): zero-sized request\n"); | |
185 | BUG(); | |
186 | } | |
187 | BUG_ON(align & (align-1)); | |
188 | ||
281dd25c YG |
189 | if (limit && bdata->node_boot_start >= limit) |
190 | return NULL; | |
191 | ||
192 | limit >>=PAGE_SHIFT; | |
193 | if (limit && end_pfn > limit) | |
194 | end_pfn = limit; | |
195 | ||
196 | eidx = end_pfn - (bdata->node_boot_start >> PAGE_SHIFT); | |
1da177e4 LT |
197 | offset = 0; |
198 | if (align && | |
199 | (bdata->node_boot_start & (align - 1UL)) != 0) | |
200 | offset = (align - (bdata->node_boot_start & (align - 1UL))); | |
201 | offset >>= PAGE_SHIFT; | |
202 | ||
203 | /* | |
204 | * We try to allocate bootmem pages above 'goal' | |
205 | * first, then we try to allocate lower pages. | |
206 | */ | |
207 | if (goal && (goal >= bdata->node_boot_start) && | |
281dd25c | 208 | ((goal >> PAGE_SHIFT) < end_pfn)) { |
1da177e4 LT |
209 | preferred = goal - bdata->node_boot_start; |
210 | ||
211 | if (bdata->last_success >= preferred) | |
281dd25c YG |
212 | if (!limit || (limit && limit > bdata->last_success)) |
213 | preferred = bdata->last_success; | |
1da177e4 LT |
214 | } else |
215 | preferred = 0; | |
216 | ||
8c0e33c1 | 217 | preferred = ALIGN(preferred, align) >> PAGE_SHIFT; |
1da177e4 LT |
218 | preferred += offset; |
219 | areasize = (size+PAGE_SIZE-1)/PAGE_SIZE; | |
220 | incr = align >> PAGE_SHIFT ? : 1; | |
221 | ||
222 | restart_scan: | |
223 | for (i = preferred; i < eidx; i += incr) { | |
224 | unsigned long j; | |
225 | i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i); | |
226 | i = ALIGN(i, incr); | |
66d43e98 HM |
227 | if (i >= eidx) |
228 | break; | |
1da177e4 LT |
229 | if (test_bit(i, bdata->node_bootmem_map)) |
230 | continue; | |
231 | for (j = i + 1; j < i + areasize; ++j) { | |
232 | if (j >= eidx) | |
233 | goto fail_block; | |
234 | if (test_bit (j, bdata->node_bootmem_map)) | |
235 | goto fail_block; | |
236 | } | |
237 | start = i; | |
238 | goto found; | |
239 | fail_block: | |
240 | i = ALIGN(j, incr); | |
241 | } | |
242 | ||
243 | if (preferred > offset) { | |
244 | preferred = offset; | |
245 | goto restart_scan; | |
246 | } | |
247 | return NULL; | |
248 | ||
249 | found: | |
250 | bdata->last_success = start << PAGE_SHIFT; | |
251 | BUG_ON(start >= eidx); | |
252 | ||
253 | /* | |
254 | * Is the next page of the previous allocation-end the start | |
255 | * of this allocation's buffer? If yes then we can 'merge' | |
256 | * the previous partial page with this allocation. | |
257 | */ | |
258 | if (align < PAGE_SIZE && | |
259 | bdata->last_offset && bdata->last_pos+1 == start) { | |
8c0e33c1 | 260 | offset = ALIGN(bdata->last_offset, align); |
1da177e4 LT |
261 | BUG_ON(offset > PAGE_SIZE); |
262 | remaining_size = PAGE_SIZE-offset; | |
263 | if (size < remaining_size) { | |
264 | areasize = 0; | |
265 | /* last_pos unchanged */ | |
266 | bdata->last_offset = offset+size; | |
267 | ret = phys_to_virt(bdata->last_pos*PAGE_SIZE + offset + | |
268 | bdata->node_boot_start); | |
269 | } else { | |
270 | remaining_size = size - remaining_size; | |
271 | areasize = (remaining_size+PAGE_SIZE-1)/PAGE_SIZE; | |
272 | ret = phys_to_virt(bdata->last_pos*PAGE_SIZE + offset + | |
273 | bdata->node_boot_start); | |
274 | bdata->last_pos = start+areasize-1; | |
275 | bdata->last_offset = remaining_size; | |
276 | } | |
277 | bdata->last_offset &= ~PAGE_MASK; | |
278 | } else { | |
279 | bdata->last_pos = start + areasize - 1; | |
280 | bdata->last_offset = size & ~PAGE_MASK; | |
281 | ret = phys_to_virt(start * PAGE_SIZE + bdata->node_boot_start); | |
282 | } | |
283 | ||
284 | /* | |
285 | * Reserve the area now: | |
286 | */ | |
287 | for (i = start; i < start+areasize; i++) | |
288 | if (unlikely(test_and_set_bit(i, bdata->node_bootmem_map))) | |
289 | BUG(); | |
290 | memset(ret, 0, size); | |
291 | return ret; | |
292 | } | |
293 | ||
294 | static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat) | |
295 | { | |
296 | struct page *page; | |
d41dee36 | 297 | unsigned long pfn; |
1da177e4 LT |
298 | bootmem_data_t *bdata = pgdat->bdata; |
299 | unsigned long i, count, total = 0; | |
300 | unsigned long idx; | |
301 | unsigned long *map; | |
302 | int gofast = 0; | |
303 | ||
304 | BUG_ON(!bdata->node_bootmem_map); | |
305 | ||
306 | count = 0; | |
307 | /* first extant page of the node */ | |
d41dee36 | 308 | pfn = bdata->node_boot_start >> PAGE_SHIFT; |
1da177e4 LT |
309 | idx = bdata->node_low_pfn - (bdata->node_boot_start >> PAGE_SHIFT); |
310 | map = bdata->node_bootmem_map; | |
311 | /* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */ | |
312 | if (bdata->node_boot_start == 0 || | |
313 | ffs(bdata->node_boot_start) - PAGE_SHIFT > ffs(BITS_PER_LONG)) | |
314 | gofast = 1; | |
315 | for (i = 0; i < idx; ) { | |
316 | unsigned long v = ~map[i / BITS_PER_LONG]; | |
d41dee36 | 317 | |
1da177e4 | 318 | if (gofast && v == ~0UL) { |
a226f6c8 | 319 | int order; |
1da177e4 | 320 | |
d41dee36 | 321 | page = pfn_to_page(pfn); |
1da177e4 | 322 | count += BITS_PER_LONG; |
1da177e4 | 323 | order = ffs(BITS_PER_LONG) - 1; |
a226f6c8 | 324 | __free_pages_bootmem(page, order); |
1da177e4 LT |
325 | i += BITS_PER_LONG; |
326 | page += BITS_PER_LONG; | |
327 | } else if (v) { | |
328 | unsigned long m; | |
d41dee36 AW |
329 | |
330 | page = pfn_to_page(pfn); | |
1da177e4 LT |
331 | for (m = 1; m && i < idx; m<<=1, page++, i++) { |
332 | if (v & m) { | |
333 | count++; | |
a226f6c8 | 334 | __free_pages_bootmem(page, 0); |
1da177e4 LT |
335 | } |
336 | } | |
337 | } else { | |
338 | i+=BITS_PER_LONG; | |
1da177e4 | 339 | } |
d41dee36 | 340 | pfn += BITS_PER_LONG; |
1da177e4 LT |
341 | } |
342 | total += count; | |
343 | ||
344 | /* | |
345 | * Now free the allocator bitmap itself, it's not | |
346 | * needed anymore: | |
347 | */ | |
348 | page = virt_to_page(bdata->node_bootmem_map); | |
349 | count = 0; | |
350 | for (i = 0; i < ((bdata->node_low_pfn-(bdata->node_boot_start >> PAGE_SHIFT))/8 + PAGE_SIZE-1)/PAGE_SIZE; i++,page++) { | |
351 | count++; | |
a226f6c8 | 352 | __free_pages_bootmem(page, 0); |
1da177e4 LT |
353 | } |
354 | total += count; | |
355 | bdata->node_bootmem_map = NULL; | |
356 | ||
357 | return total; | |
358 | } | |
359 | ||
360 | unsigned long __init init_bootmem_node (pg_data_t *pgdat, unsigned long freepfn, unsigned long startpfn, unsigned long endpfn) | |
361 | { | |
362 | return(init_bootmem_core(pgdat, freepfn, startpfn, endpfn)); | |
363 | } | |
364 | ||
365 | void __init reserve_bootmem_node (pg_data_t *pgdat, unsigned long physaddr, unsigned long size) | |
366 | { | |
367 | reserve_bootmem_core(pgdat->bdata, physaddr, size); | |
368 | } | |
369 | ||
370 | void __init free_bootmem_node (pg_data_t *pgdat, unsigned long physaddr, unsigned long size) | |
371 | { | |
372 | free_bootmem_core(pgdat->bdata, physaddr, size); | |
373 | } | |
374 | ||
375 | unsigned long __init free_all_bootmem_node (pg_data_t *pgdat) | |
376 | { | |
377 | return(free_all_bootmem_core(pgdat)); | |
378 | } | |
379 | ||
380 | unsigned long __init init_bootmem (unsigned long start, unsigned long pages) | |
381 | { | |
382 | max_low_pfn = pages; | |
383 | min_low_pfn = start; | |
384 | return(init_bootmem_core(NODE_DATA(0), start, 0, pages)); | |
385 | } | |
386 | ||
387 | #ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE | |
388 | void __init reserve_bootmem (unsigned long addr, unsigned long size) | |
389 | { | |
390 | reserve_bootmem_core(NODE_DATA(0)->bdata, addr, size); | |
391 | } | |
392 | #endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */ | |
393 | ||
394 | void __init free_bootmem (unsigned long addr, unsigned long size) | |
395 | { | |
396 | free_bootmem_core(NODE_DATA(0)->bdata, addr, size); | |
397 | } | |
398 | ||
399 | unsigned long __init free_all_bootmem (void) | |
400 | { | |
401 | return(free_all_bootmem_core(NODE_DATA(0))); | |
402 | } | |
403 | ||
a8062231 | 404 | void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align, unsigned long goal) |
1da177e4 | 405 | { |
679bc9fb | 406 | bootmem_data_t *bdata; |
1da177e4 LT |
407 | void *ptr; |
408 | ||
679bc9fb KH |
409 | list_for_each_entry(bdata, &bdata_list, list) |
410 | if ((ptr = __alloc_bootmem_core(bdata, size, align, goal, 0))) | |
1da177e4 | 411 | return(ptr); |
a8062231 AK |
412 | return NULL; |
413 | } | |
1da177e4 | 414 | |
a8062231 AK |
415 | void * __init __alloc_bootmem(unsigned long size, unsigned long align, unsigned long goal) |
416 | { | |
417 | void *mem = __alloc_bootmem_nopanic(size,align,goal); | |
418 | if (mem) | |
419 | return mem; | |
1da177e4 LT |
420 | /* |
421 | * Whoops, we cannot satisfy the allocation request. | |
422 | */ | |
423 | printk(KERN_ALERT "bootmem alloc of %lu bytes failed!\n", size); | |
424 | panic("Out of memory"); | |
425 | return NULL; | |
426 | } | |
427 | ||
281dd25c | 428 | |
008857c1 RT |
429 | void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size, unsigned long align, |
430 | unsigned long goal) | |
1da177e4 LT |
431 | { |
432 | void *ptr; | |
433 | ||
008857c1 | 434 | ptr = __alloc_bootmem_core(pgdat->bdata, size, align, goal, 0); |
1da177e4 LT |
435 | if (ptr) |
436 | return (ptr); | |
437 | ||
008857c1 | 438 | return __alloc_bootmem(size, align, goal); |
1da177e4 LT |
439 | } |
440 | ||
008857c1 RT |
441 | #define LOW32LIMIT 0xffffffff |
442 | ||
443 | void * __init __alloc_bootmem_low(unsigned long size, unsigned long align, unsigned long goal) | |
444 | { | |
679bc9fb | 445 | bootmem_data_t *bdata; |
008857c1 RT |
446 | void *ptr; |
447 | ||
679bc9fb KH |
448 | list_for_each_entry(bdata, &bdata_list, list) |
449 | if ((ptr = __alloc_bootmem_core(bdata, size, | |
008857c1 RT |
450 | align, goal, LOW32LIMIT))) |
451 | return(ptr); | |
452 | ||
453 | /* | |
454 | * Whoops, we cannot satisfy the allocation request. | |
455 | */ | |
456 | printk(KERN_ALERT "low bootmem alloc of %lu bytes failed!\n", size); | |
457 | panic("Out of low memory"); | |
458 | return NULL; | |
459 | } | |
460 | ||
461 | void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size, | |
462 | unsigned long align, unsigned long goal) | |
463 | { | |
464 | return __alloc_bootmem_core(pgdat->bdata, size, align, goal, LOW32LIMIT); | |
465 | } |