x86, mm: use pfn instead of pos in split_mem_range
[deliverable/linux.git] / arch / x86 / mm / init.c
CommitLineData
5a0e3ad6 1#include <linux/gfp.h>
2c1b284e 2#include <linux/initrd.h>
540aca06 3#include <linux/ioport.h>
e5b2bb55 4#include <linux/swap.h>
a9ce6bc1 5#include <linux/memblock.h>
17623915 6#include <linux/bootmem.h> /* for max_low_pfn */
540aca06 7
e5b2bb55 8#include <asm/cacheflush.h>
f765090a 9#include <asm/e820.h>
4fcb2083 10#include <asm/init.h>
e5b2bb55 11#include <asm/page.h>
540aca06 12#include <asm/page_types.h>
e5b2bb55 13#include <asm/sections.h>
49834396 14#include <asm/setup.h>
f765090a 15#include <asm/tlbflush.h>
9518e0e4 16#include <asm/tlb.h>
76c06927 17#include <asm/proto.h>
17623915 18#include <asm/dma.h> /* for MAX_DMA_PFN */
9518e0e4 19
5c51bdbe
YL
20#include "mm_internal.h"
21
cf470659
YL
22static unsigned long __initdata pgt_buf_start;
23static unsigned long __initdata pgt_buf_end;
24static unsigned long __initdata pgt_buf_top;
f765090a 25
9985b4c6
YL
26static unsigned long min_pfn_mapped;
27
ddd3509d
SS
28/*
29 * Pages returned are already directly mapped.
30 *
31 * Changing that is likely to break Xen, see commit:
32 *
33 * 279b706 x86,xen: introduce x86_init.mapping.pagetable_reserve
34 *
35 * for detailed information.
36 */
22c8ca2a 37__ref void *alloc_low_pages(unsigned int num)
5c51bdbe
YL
38{
39 unsigned long pfn;
22c8ca2a 40 int i;
5c51bdbe
YL
41
42#ifdef CONFIG_X86_64
43 if (after_bootmem) {
22c8ca2a 44 unsigned int order;
5c51bdbe 45
22c8ca2a
YL
46 order = get_order((unsigned long)num << PAGE_SHIFT);
47 return (void *)__get_free_pages(GFP_ATOMIC | __GFP_NOTRACK |
48 __GFP_ZERO, order);
5c51bdbe
YL
49 }
50#endif
51
22c8ca2a 52 if ((pgt_buf_end + num) >= pgt_buf_top) {
5c51bdbe
YL
53 unsigned long ret;
54 if (min_pfn_mapped >= max_pfn_mapped)
55 panic("alloc_low_page: ran out of memory");
56 ret = memblock_find_in_range(min_pfn_mapped << PAGE_SHIFT,
57 max_pfn_mapped << PAGE_SHIFT,
22c8ca2a 58 PAGE_SIZE * num , PAGE_SIZE);
5c51bdbe
YL
59 if (!ret)
60 panic("alloc_low_page: can not alloc memory");
22c8ca2a 61 memblock_reserve(ret, PAGE_SIZE * num);
5c51bdbe 62 pfn = ret >> PAGE_SHIFT;
22c8ca2a
YL
63 } else {
64 pfn = pgt_buf_end;
65 pgt_buf_end += num;
66 }
67
68 for (i = 0; i < num; i++) {
69 void *adr;
70
71 adr = __va((pfn + i) << PAGE_SHIFT);
72 clear_page(adr);
73 }
5c51bdbe 74
22c8ca2a 75 return __va(pfn << PAGE_SHIFT);
5c51bdbe
YL
76}
77
8d57470d
YL
78/* need 4 4k for initial PMD_SIZE, 4k for 0-ISA_END_ADDRESS */
79#define INIT_PGT_BUF_SIZE (5 * PAGE_SIZE)
80RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE);
81void __init early_alloc_pgt_buf(void)
82{
83 unsigned long tables = INIT_PGT_BUF_SIZE;
84 phys_addr_t base;
85
86 base = __pa(extend_brk(tables, PAGE_SIZE));
87
88 pgt_buf_start = base >> PAGE_SHIFT;
89 pgt_buf_end = pgt_buf_start;
90 pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
91}
92
f765090a
PE
93int after_bootmem;
94
95int direct_gbpages
96#ifdef CONFIG_DIRECT_GBPAGES
97 = 1
98#endif
99;
100
148b2098
YL
101static void __init init_gbpages(void)
102{
103#ifdef CONFIG_X86_64
104 if (direct_gbpages && cpu_has_gbpages)
105 printk(KERN_INFO "Using GB pages for direct mapping\n");
106 else
107 direct_gbpages = 0;
108#endif
109}
110
844ab6f9
JS
111struct map_range {
112 unsigned long start;
113 unsigned long end;
114 unsigned page_size_mask;
115};
116
fa62aafe 117static int page_size_mask;
f765090a 118
22ddfcaa 119static void __init probe_page_size_mask(void)
fa62aafe 120{
148b2098
YL
121 init_gbpages();
122
fa62aafe
YL
123#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
124 /*
125 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
126 * This will simplify cpa(), which otherwise needs to support splitting
127 * large pages into small in interrupt context, etc.
128 */
129 if (direct_gbpages)
130 page_size_mask |= 1 << PG_LEVEL_1G;
131 if (cpu_has_pse)
132 page_size_mask |= 1 << PG_LEVEL_2M;
133#endif
134
135 /* Enable PSE if available */
136 if (cpu_has_pse)
137 set_in_cr4(X86_CR4_PSE);
138
139 /* Enable PGE if available */
140 if (cpu_has_pge) {
141 set_in_cr4(X86_CR4_PGE);
142 __supported_pte_mask |= _PAGE_GLOBAL;
143 }
144}
279b706b 145
f765090a
PE
146#ifdef CONFIG_X86_32
147#define NR_RANGE_MR 3
148#else /* CONFIG_X86_64 */
149#define NR_RANGE_MR 5
150#endif
151
dc9dd5cc
JB
152static int __meminit save_mr(struct map_range *mr, int nr_range,
153 unsigned long start_pfn, unsigned long end_pfn,
154 unsigned long page_size_mask)
f765090a
PE
155{
156 if (start_pfn < end_pfn) {
157 if (nr_range >= NR_RANGE_MR)
158 panic("run out of range for init_memory_mapping\n");
159 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
160 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
161 mr[nr_range].page_size_mask = page_size_mask;
162 nr_range++;
163 }
164
165 return nr_range;
166}
167
aeebe84c
YL
168/*
169 * adjust the page_size_mask for small range to go with
170 * big page size instead small one if nearby are ram too.
171 */
172static void __init_refok adjust_range_page_size_mask(struct map_range *mr,
173 int nr_range)
174{
175 int i;
176
177 for (i = 0; i < nr_range; i++) {
178 if ((page_size_mask & (1<<PG_LEVEL_2M)) &&
179 !(mr[i].page_size_mask & (1<<PG_LEVEL_2M))) {
180 unsigned long start = round_down(mr[i].start, PMD_SIZE);
181 unsigned long end = round_up(mr[i].end, PMD_SIZE);
182
183#ifdef CONFIG_X86_32
184 if ((end >> PAGE_SHIFT) > max_low_pfn)
185 continue;
186#endif
187
188 if (memblock_is_region_memory(start, end - start))
189 mr[i].page_size_mask |= 1<<PG_LEVEL_2M;
190 }
191 if ((page_size_mask & (1<<PG_LEVEL_1G)) &&
192 !(mr[i].page_size_mask & (1<<PG_LEVEL_1G))) {
193 unsigned long start = round_down(mr[i].start, PUD_SIZE);
194 unsigned long end = round_up(mr[i].end, PUD_SIZE);
195
196 if (memblock_is_region_memory(start, end - start))
197 mr[i].page_size_mask |= 1<<PG_LEVEL_1G;
198 }
199 }
200}
201
4e33e065
YL
202static int __meminit split_mem_range(struct map_range *mr, int nr_range,
203 unsigned long start,
204 unsigned long end)
f765090a 205{
f765090a 206 unsigned long start_pfn, end_pfn;
1829ae9a 207 unsigned long pfn;
4e33e065 208 int i;
f765090a
PE
209
210 /* head if not big page alignment ? */
1829ae9a 211 pfn = start_pfn = PFN_DOWN(start);
f765090a
PE
212#ifdef CONFIG_X86_32
213 /*
214 * Don't use a large page for the first 2/4MB of memory
215 * because there are often fixed size MTRRs in there
216 * and overlapping MTRRs into large pages can cause
217 * slowdowns.
218 */
1829ae9a 219 if (pfn == 0)
84d77001 220 end_pfn = PFN_DOWN(PMD_SIZE);
f765090a 221 else
1829ae9a 222 end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
f765090a 223#else /* CONFIG_X86_64 */
1829ae9a 224 end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
f765090a 225#endif
84d77001
YL
226 if (end_pfn > PFN_DOWN(end))
227 end_pfn = PFN_DOWN(end);
f765090a
PE
228 if (start_pfn < end_pfn) {
229 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
1829ae9a 230 pfn = end_pfn;
f765090a
PE
231 }
232
233 /* big page (2M) range */
1829ae9a 234 start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
f765090a 235#ifdef CONFIG_X86_32
84d77001 236 end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
f765090a 237#else /* CONFIG_X86_64 */
1829ae9a 238 end_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
84d77001
YL
239 if (end_pfn > PFN_DOWN(round_down(end, PMD_SIZE)))
240 end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
f765090a
PE
241#endif
242
243 if (start_pfn < end_pfn) {
244 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
245 page_size_mask & (1<<PG_LEVEL_2M));
1829ae9a 246 pfn = end_pfn;
f765090a
PE
247 }
248
249#ifdef CONFIG_X86_64
250 /* big page (1G) range */
1829ae9a 251 start_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
84d77001 252 end_pfn = PFN_DOWN(round_down(end, PUD_SIZE));
f765090a
PE
253 if (start_pfn < end_pfn) {
254 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
255 page_size_mask &
256 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
1829ae9a 257 pfn = end_pfn;
f765090a
PE
258 }
259
260 /* tail is not big page (1G) alignment */
1829ae9a 261 start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
84d77001 262 end_pfn = PFN_DOWN(round_down(end, PMD_SIZE));
f765090a
PE
263 if (start_pfn < end_pfn) {
264 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
265 page_size_mask & (1<<PG_LEVEL_2M));
1829ae9a 266 pfn = end_pfn;
f765090a
PE
267 }
268#endif
269
270 /* tail is not big page (2M) alignment */
1829ae9a 271 start_pfn = pfn;
84d77001 272 end_pfn = PFN_DOWN(end);
f765090a
PE
273 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
274
275 /* try to merge same page size and continuous */
276 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
277 unsigned long old_start;
278 if (mr[i].end != mr[i+1].start ||
279 mr[i].page_size_mask != mr[i+1].page_size_mask)
280 continue;
281 /* move it */
282 old_start = mr[i].start;
283 memmove(&mr[i], &mr[i+1],
284 (nr_range - 1 - i) * sizeof(struct map_range));
285 mr[i--].start = old_start;
286 nr_range--;
287 }
288
aeebe84c
YL
289 if (!after_bootmem)
290 adjust_range_page_size_mask(mr, nr_range);
291
f765090a 292 for (i = 0; i < nr_range; i++)
365811d6
BH
293 printk(KERN_DEBUG " [mem %#010lx-%#010lx] page %s\n",
294 mr[i].start, mr[i].end - 1,
f765090a
PE
295 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
296 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
297
4e33e065
YL
298 return nr_range;
299}
300
66520ebc
JS
301static struct range pfn_mapped[E820_X_MAX];
302static int nr_pfn_mapped;
303
304static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn)
305{
306 nr_pfn_mapped = add_range_with_merge(pfn_mapped, E820_X_MAX,
307 nr_pfn_mapped, start_pfn, end_pfn);
308 nr_pfn_mapped = clean_sort_range(pfn_mapped, E820_X_MAX);
309
310 max_pfn_mapped = max(max_pfn_mapped, end_pfn);
311
312 if (start_pfn < (1UL<<(32-PAGE_SHIFT)))
313 max_low_pfn_mapped = max(max_low_pfn_mapped,
314 min(end_pfn, 1UL<<(32-PAGE_SHIFT)));
315}
316
317bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn)
318{
319 int i;
320
321 for (i = 0; i < nr_pfn_mapped; i++)
322 if ((start_pfn >= pfn_mapped[i].start) &&
323 (end_pfn <= pfn_mapped[i].end))
324 return true;
325
326 return false;
327}
328
4e33e065
YL
329/*
330 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
331 * This runs before bootmem is initialized and gets pages directly from
332 * the physical memory. To access them they are temporarily mapped.
333 */
334unsigned long __init_refok init_memory_mapping(unsigned long start,
335 unsigned long end)
336{
337 struct map_range mr[NR_RANGE_MR];
338 unsigned long ret = 0;
339 int nr_range, i;
340
341 pr_info("init_memory_mapping: [mem %#010lx-%#010lx]\n",
342 start, end - 1);
343
344 memset(mr, 0, sizeof(mr));
345 nr_range = split_mem_range(mr, 0, start, end);
346
f765090a
PE
347 for (i = 0; i < nr_range; i++)
348 ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
349 mr[i].page_size_mask);
f765090a 350
66520ebc
JS
351 add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT);
352
c14fa0b6
YL
353 return ret >> PAGE_SHIFT;
354}
355
66520ebc 356/*
8d57470d 357 * would have hole in the middle or ends, and only ram parts will be mapped.
66520ebc 358 */
8d57470d
YL
359static unsigned long __init init_range_memory_mapping(
360 unsigned long range_start,
f763ad1d 361 unsigned long range_end)
66520ebc
JS
362{
363 unsigned long start_pfn, end_pfn;
8d57470d 364 unsigned long mapped_ram_size = 0;
66520ebc
JS
365 int i;
366
66520ebc
JS
367 for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
368 u64 start = (u64)start_pfn << PAGE_SHIFT;
369 u64 end = (u64)end_pfn << PAGE_SHIFT;
370
f763ad1d 371 if (end <= range_start)
66520ebc
JS
372 continue;
373
f763ad1d
YL
374 if (start < range_start)
375 start = range_start;
376
377 if (start >= range_end)
66520ebc
JS
378 continue;
379
f763ad1d
YL
380 if (end > range_end)
381 end = range_end;
66520ebc 382
f763ad1d 383 init_memory_mapping(start, end);
8d57470d
YL
384
385 mapped_ram_size += end - start;
66520ebc 386 }
8d57470d
YL
387
388 return mapped_ram_size;
66520ebc
JS
389}
390
8d57470d
YL
391/* (PUD_SHIFT-PMD_SHIFT)/2 */
392#define STEP_SIZE_SHIFT 5
c14fa0b6
YL
393void __init init_mem_mapping(void)
394{
8d57470d
YL
395 unsigned long end, real_end, start, last_start;
396 unsigned long step_size;
397 unsigned long addr;
398 unsigned long mapped_ram_size = 0;
399 unsigned long new_mapped_ram_size;
ab951937 400
c14fa0b6
YL
401 probe_page_size_mask();
402
c14fa0b6 403#ifdef CONFIG_X86_64
ab951937 404 end = max_pfn << PAGE_SHIFT;
c14fa0b6 405#else
ab951937 406 end = max_low_pfn << PAGE_SHIFT;
c14fa0b6 407#endif
ab951937 408
f763ad1d
YL
409 /* the ISA range is always mapped regardless of memory holes */
410 init_memory_mapping(0, ISA_END_ADDRESS);
8d57470d
YL
411
412 /* xen has big range in reserved near end of ram, skip it at first */
413 addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE,
414 PAGE_SIZE);
415 real_end = addr + PMD_SIZE;
416
417 /* step_size need to be small so pgt_buf from BRK could cover it */
418 step_size = PMD_SIZE;
419 max_pfn_mapped = 0; /* will get exact value next */
420 min_pfn_mapped = real_end >> PAGE_SHIFT;
421 last_start = start = real_end;
422 while (last_start > ISA_END_ADDRESS) {
423 if (last_start > step_size) {
424 start = round_down(last_start - 1, step_size);
425 if (start < ISA_END_ADDRESS)
426 start = ISA_END_ADDRESS;
427 } else
428 start = ISA_END_ADDRESS;
429 new_mapped_ram_size = init_range_memory_mapping(start,
430 last_start);
431 last_start = start;
432 min_pfn_mapped = last_start >> PAGE_SHIFT;
433 /* only increase step_size after big range get mapped */
434 if (new_mapped_ram_size > mapped_ram_size)
435 step_size <<= STEP_SIZE_SHIFT;
436 mapped_ram_size += new_mapped_ram_size;
437 }
438
439 if (real_end < end)
440 init_range_memory_mapping(real_end, end);
441
f763ad1d
YL
442#ifdef CONFIG_X86_64
443 if (max_pfn > max_low_pfn) {
444 /* can we preseve max_low_pfn ?*/
445 max_low_pfn = max_pfn;
446 }
719272c4
YL
447#else
448 early_ioremap_page_table_range_init();
449 load_cr3(swapper_pg_dir);
450 __flush_tlb_all();
f763ad1d 451#endif
719272c4 452
c14fa0b6 453 early_memtest(0, max_pfn_mapped << PAGE_SHIFT);
22ddfcaa 454}
e5b2bb55 455
540aca06
PE
456/*
457 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
458 * is valid. The argument is a physical page number.
459 *
460 *
461 * On x86, access has to be given to the first megabyte of ram because that area
462 * contains bios code and data regions used by X and dosemu and similar apps.
463 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
464 * mmio resources as well as potential bios/acpi data regions.
465 */
466int devmem_is_allowed(unsigned long pagenr)
467{
73e8f3d7 468 if (pagenr < 256)
540aca06
PE
469 return 1;
470 if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
471 return 0;
472 if (!page_is_ram(pagenr))
473 return 1;
474 return 0;
475}
476
e5b2bb55
PE
477void free_init_pages(char *what, unsigned long begin, unsigned long end)
478{
c967da6a
YL
479 unsigned long addr;
480 unsigned long begin_aligned, end_aligned;
e5b2bb55 481
c967da6a
YL
482 /* Make sure boundaries are page aligned */
483 begin_aligned = PAGE_ALIGN(begin);
484 end_aligned = end & PAGE_MASK;
485
486 if (WARN_ON(begin_aligned != begin || end_aligned != end)) {
487 begin = begin_aligned;
488 end = end_aligned;
489 }
490
491 if (begin >= end)
e5b2bb55
PE
492 return;
493
c967da6a
YL
494 addr = begin;
495
e5b2bb55
PE
496 /*
497 * If debugging page accesses then do not free this memory but
498 * mark them not present - any buggy init-section access will
499 * create a kernel page fault:
500 */
501#ifdef CONFIG_DEBUG_PAGEALLOC
365811d6
BH
502 printk(KERN_INFO "debug: unmapping init [mem %#010lx-%#010lx]\n",
503 begin, end - 1);
e5b2bb55
PE
504 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
505#else
506 /*
507 * We just marked the kernel text read only above, now that
508 * we are going to free part of that, we need to make that
5bd5a452 509 * writeable and non-executable first.
e5b2bb55 510 */
5bd5a452 511 set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
e5b2bb55
PE
512 set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
513
514 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
515
516 for (; addr < end; addr += PAGE_SIZE) {
517 ClearPageReserved(virt_to_page(addr));
518 init_page_count(virt_to_page(addr));
c967da6a 519 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
e5b2bb55
PE
520 free_page(addr);
521 totalram_pages++;
522 }
523#endif
524}
525
526void free_initmem(void)
527{
528 free_init_pages("unused kernel memory",
529 (unsigned long)(&__init_begin),
530 (unsigned long)(&__init_end));
531}
731ddea6
PE
532
533#ifdef CONFIG_BLK_DEV_INITRD
0d26d1d8 534void __init free_initrd_mem(unsigned long start, unsigned long end)
731ddea6 535{
c967da6a
YL
536 /*
537 * end could be not aligned, and We can not align that,
538 * decompresser could be confused by aligned initrd_end
539 * We already reserve the end partial page before in
540 * - i386_start_kernel()
541 * - x86_64_start_kernel()
542 * - relocate_initrd()
543 * So here We can do PAGE_ALIGN() safely to get partial page to be freed
544 */
545 free_init_pages("initrd memory", start, PAGE_ALIGN(end));
731ddea6
PE
546}
547#endif
17623915
PE
548
549void __init zone_sizes_init(void)
550{
551 unsigned long max_zone_pfns[MAX_NR_ZONES];
552
553 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
554
555#ifdef CONFIG_ZONE_DMA
556 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
557#endif
558#ifdef CONFIG_ZONE_DMA32
559 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
560#endif
561 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
562#ifdef CONFIG_HIGHMEM
563 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
564#endif
565
566 free_area_init_nodes(max_zone_pfns);
567}
568
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