?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
x86, cpa: dont use large pages for kernel identity mapping with DEBUG_PAGEALLOC
[linux-2.6/mini2440.git] / arch / x86 / mm / init_64.c
blob9d7587ac1ebc7ad1c363d54f8d71e70f8b9a0bae
1 /*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
6 * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
7 */
8
9 #include <linux/signal.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/ptrace.h>
16 #include <linux/mman.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/smp.h>
20 #include <linux/init.h>
21 #include <linux/initrd.h>
22 #include <linux/pagemap.h>
23 #include <linux/bootmem.h>
24 #include <linux/proc_fs.h>
25 #include <linux/pci.h>
26 #include <linux/pfn.h>
27 #include <linux/poison.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/module.h>
30 #include <linux/memory_hotplug.h>
31 #include <linux/nmi.h>
32
33 #include <asm/processor.h>
34 #include <asm/system.h>
35 #include <asm/uaccess.h>
36 #include <asm/pgtable.h>
37 #include <asm/pgalloc.h>
38 #include <asm/dma.h>
39 #include <asm/fixmap.h>
40 #include <asm/e820.h>
41 #include <asm/apic.h>
42 #include <asm/tlb.h>
43 #include <asm/mmu_context.h>
44 #include <asm/proto.h>
45 #include <asm/smp.h>
46 #include <asm/sections.h>
47 #include <asm/kdebug.h>
48 #include <asm/numa.h>
49 #include <asm/cacheflush.h>
50
51 /*
52 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
53 * The direct mapping extends to max_pfn_mapped, so that we can directly access
54 * apertures, ACPI and other tables without having to play with fixmaps.
55 */
56 unsigned long max_low_pfn_mapped;
57 unsigned long max_pfn_mapped;
58
59 static unsigned long dma_reserve __initdata;
60
61 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
62
63 int direct_gbpages
64 #ifdef CONFIG_DIRECT_GBPAGES
65 = 1
66 #endif
67 ;
68
69 static int __init parse_direct_gbpages_off(char *arg)
70 {
71 direct_gbpages = 0;
72 return 0;
73 }
74 early_param("nogbpages", parse_direct_gbpages_off);
75
76 static int __init parse_direct_gbpages_on(char *arg)
77 {
78 direct_gbpages = 1;
79 return 0;
80 }
81 early_param("gbpages", parse_direct_gbpages_on);
82
83 /*
84 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
85 * physical space so we can cache the place of the first one and move
86 * around without checking the pgd every time.
87 */
88
89 int after_bootmem;
90
91 /*
92 * NOTE: This function is marked __ref because it calls __init function
93 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
94 */
95 static __ref void *spp_getpage(void)
96 {
97 void *ptr;
98
99 if (after_bootmem)
100 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
101 else
102 ptr = alloc_bootmem_pages(PAGE_SIZE);
103
104 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
105 panic("set_pte_phys: cannot allocate page data %s\n",
106 after_bootmem ? "after bootmem" : "");
107 }
108
109 pr_debug("spp_getpage %p\n", ptr);
110
111 return ptr;
112 }
113
114 void
115 set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
116 {
117 pud_t *pud;
118 pmd_t *pmd;
119 pte_t *pte;
120
121 pud = pud_page + pud_index(vaddr);
122 if (pud_none(*pud)) {
123 pmd = (pmd_t *) spp_getpage();
124 pud_populate(&init_mm, pud, pmd);
125 if (pmd != pmd_offset(pud, 0)) {
126 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
127 pmd, pmd_offset(pud, 0));
128 return;
129 }
130 }
131 pmd = pmd_offset(pud, vaddr);
132 if (pmd_none(*pmd)) {
133 pte = (pte_t *) spp_getpage();
134 pmd_populate_kernel(&init_mm, pmd, pte);
135 if (pte != pte_offset_kernel(pmd, 0)) {
136 printk(KERN_ERR "PAGETABLE BUG #02!\n");
137 return;
138 }
139 }
140
141 pte = pte_offset_kernel(pmd, vaddr);
142 if (!pte_none(*pte) && pte_val(new_pte) &&
143 pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
144 pte_ERROR(*pte);
145 set_pte(pte, new_pte);
146
147 /*
148 * It's enough to flush this one mapping.
149 * (PGE mappings get flushed as well)
150 */
151 __flush_tlb_one(vaddr);
152 }
153
154 void
155 set_pte_vaddr(unsigned long vaddr, pte_t pteval)
156 {
157 pgd_t *pgd;
158 pud_t *pud_page;
159
160 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
161
162 pgd = pgd_offset_k(vaddr);
163 if (pgd_none(*pgd)) {
164 printk(KERN_ERR
165 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
166 return;
167 }
168 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
169 set_pte_vaddr_pud(pud_page, vaddr, pteval);
170 }
171
172 /*
173 * Create large page table mappings for a range of physical addresses.
174 */
175 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
176 pgprot_t prot)
177 {
178 pgd_t *pgd;
179 pud_t *pud;
180 pmd_t *pmd;
181
182 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
183 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
184 pgd = pgd_offset_k((unsigned long)__va(phys));
185 if (pgd_none(*pgd)) {
186 pud = (pud_t *) spp_getpage();
187 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
188 _PAGE_USER));
189 }
190 pud = pud_offset(pgd, (unsigned long)__va(phys));
191 if (pud_none(*pud)) {
192 pmd = (pmd_t *) spp_getpage();
193 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
194 _PAGE_USER));
195 }
196 pmd = pmd_offset(pud, phys);
197 BUG_ON(!pmd_none(*pmd));
198 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
199 }
200 }
201
202 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
203 {
204 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
205 }
206
207 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
208 {
209 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
210 }
211
212 /*
213 * The head.S code sets up the kernel high mapping:
214 *
215 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
216 *
217 * phys_addr holds the negative offset to the kernel, which is added
218 * to the compile time generated pmds. This results in invalid pmds up
219 * to the point where we hit the physaddr 0 mapping.
220 *
221 * We limit the mappings to the region from _text to _end. _end is
222 * rounded up to the 2MB boundary. This catches the invalid pmds as
223 * well, as they are located before _text:
224 */
225 void __init cleanup_highmap(void)
226 {
227 unsigned long vaddr = __START_KERNEL_map;
228 unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
229 pmd_t *pmd = level2_kernel_pgt;
230 pmd_t *last_pmd = pmd + PTRS_PER_PMD;
231
232 for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
233 if (pmd_none(*pmd))
234 continue;
235 if (vaddr < (unsigned long) _text || vaddr > end)
236 set_pmd(pmd, __pmd(0));
237 }
238 }
239
240 static unsigned long __initdata table_start;
241 static unsigned long __meminitdata table_end;
242 static unsigned long __meminitdata table_top;
243
244 static __ref void *alloc_low_page(unsigned long *phys)
245 {
246 unsigned long pfn = table_end++;
247 void *adr;
248
249 if (after_bootmem) {
250 adr = (void *)get_zeroed_page(GFP_ATOMIC);
251 *phys = __pa(adr);
252
253 return adr;
254 }
255
256 if (pfn >= table_top)
257 panic("alloc_low_page: ran out of memory");
258
259 adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
260 memset(adr, 0, PAGE_SIZE);
261 *phys = pfn * PAGE_SIZE;
262 return adr;
263 }
264
265 static __ref void unmap_low_page(void *adr)
266 {
267 if (after_bootmem)
268 return;
269
270 early_iounmap(adr, PAGE_SIZE);
271 }
272
273 static int physical_mapping_iter;
274
275 static unsigned long __meminit
276 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end)
277 {
278 unsigned pages = 0;
279 unsigned long last_map_addr = end;
280 int i;
281
282 pte_t *pte = pte_page + pte_index(addr);
283
284 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
285
286 if (addr >= end) {
287 if (!after_bootmem) {
288 for(; i < PTRS_PER_PTE; i++, pte++)
289 set_pte(pte, __pte(0));
290 }
291 break;
292 }
293
294 if (pte_val(*pte))
295 goto repeat_set_pte;
296
297 if (0)
298 printk(" pte=%p addr=%lx pte=%016lx\n",
299 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
300 pages++;
301 repeat_set_pte:
302 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL));
303 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
304 }
305
306 if (physical_mapping_iter == 1)
307 update_page_count(PG_LEVEL_4K, pages);
308
309 return last_map_addr;
310 }
311
312 static unsigned long __meminit
313 phys_pte_update(pmd_t *pmd, unsigned long address, unsigned long end)
314 {
315 pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
316
317 return phys_pte_init(pte, address, end);
318 }
319
320 static unsigned long __meminit
321 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
322 unsigned long page_size_mask)
323 {
324 unsigned long pages = 0;
325 unsigned long last_map_addr = end;
326
327 int i = pmd_index(address);
328
329 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
330 unsigned long pte_phys;
331 pmd_t *pmd = pmd_page + pmd_index(address);
332 pte_t *pte;
333
334 if (address >= end) {
335 if (!after_bootmem) {
336 for (; i < PTRS_PER_PMD; i++, pmd++)
337 set_pmd(pmd, __pmd(0));
338 }
339 break;
340 }
341
342 if (pmd_val(*pmd)) {
343 if (!pmd_large(*pmd)) {
344 spin_lock(&init_mm.page_table_lock);
345 last_map_addr = phys_pte_update(pmd, address,
346 end);
347 spin_unlock(&init_mm.page_table_lock);
348 continue;
349 }
350 goto repeat_set_pte;
351 }
352
353 if (page_size_mask & (1<<PG_LEVEL_2M)) {
354 pages++;
355 repeat_set_pte:
356 spin_lock(&init_mm.page_table_lock);
357 set_pte((pte_t *)pmd,
358 pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
359 spin_unlock(&init_mm.page_table_lock);
360 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
361 continue;
362 }
363
364 pte = alloc_low_page(&pte_phys);
365 last_map_addr = phys_pte_init(pte, address, end);
366 unmap_low_page(pte);
367
368 spin_lock(&init_mm.page_table_lock);
369 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
370 spin_unlock(&init_mm.page_table_lock);
371 }
372 if (physical_mapping_iter == 1)
373 update_page_count(PG_LEVEL_2M, pages);
374 return last_map_addr;
375 }
376
377 static unsigned long __meminit
378 phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end,
379 unsigned long page_size_mask)
380 {
381 pmd_t *pmd = pmd_offset(pud, 0);
382 unsigned long last_map_addr;
383
384 last_map_addr = phys_pmd_init(pmd, address, end, page_size_mask);
385 __flush_tlb_all();
386 return last_map_addr;
387 }
388
389 static unsigned long __meminit
390 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
391 unsigned long page_size_mask)
392 {
393 unsigned long pages = 0;
394 unsigned long last_map_addr = end;
395 int i = pud_index(addr);
396
397 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
398 unsigned long pmd_phys;
399 pud_t *pud = pud_page + pud_index(addr);
400 pmd_t *pmd;
401
402 if (addr >= end)
403 break;
404
405 if (!after_bootmem &&
406 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
407 set_pud(pud, __pud(0));
408 continue;
409 }
410
411 if (pud_val(*pud)) {
412 if (!pud_large(*pud)) {
413 last_map_addr = phys_pmd_update(pud, addr, end,
414 page_size_mask);
415 continue;
416 }
417
418 goto repeat_set_pte;
419 }
420
421 if (page_size_mask & (1<<PG_LEVEL_1G)) {
422 pages++;
423 repeat_set_pte:
424 spin_lock(&init_mm.page_table_lock);
425 set_pte((pte_t *)pud,
426 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
427 spin_unlock(&init_mm.page_table_lock);
428 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
429 continue;
430 }
431
432 pmd = alloc_low_page(&pmd_phys);
433 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask);
434 unmap_low_page(pmd);
435
436 spin_lock(&init_mm.page_table_lock);
437 pud_populate(&init_mm, pud, __va(pmd_phys));
438 spin_unlock(&init_mm.page_table_lock);
439 }
440 __flush_tlb_all();
441
442 if (physical_mapping_iter == 1)
443 update_page_count(PG_LEVEL_1G, pages);
444
445 return last_map_addr;
446 }
447
448 static unsigned long __meminit
449 phys_pud_update(pgd_t *pgd, unsigned long addr, unsigned long end,
450 unsigned long page_size_mask)
451 {
452 pud_t *pud;
453
454 pud = (pud_t *)pgd_page_vaddr(*pgd);
455
456 return phys_pud_init(pud, addr, end, page_size_mask);
457 }
458
459 static void __init find_early_table_space(unsigned long end, int use_pse,
460 int use_gbpages)
461 {
462 unsigned long puds, pmds, ptes, tables, start;
463
464 puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
465 tables = round_up(puds * sizeof(pud_t), PAGE_SIZE);
466 if (use_gbpages) {
467 unsigned long extra;
468 extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
469 pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
470 } else
471 pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
472 tables += round_up(pmds * sizeof(pmd_t), PAGE_SIZE);
473
474 if (use_pse) {
475 unsigned long extra;
476 extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
477 ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
478 } else
479 ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
480 tables += round_up(ptes * sizeof(pte_t), PAGE_SIZE);
481
482 /*
483 * RED-PEN putting page tables only on node 0 could
484 * cause a hotspot and fill up ZONE_DMA. The page tables
485 * need roughly 0.5KB per GB.
486 */
487 start = 0x8000;
488 table_start = find_e820_area(start, end, tables, PAGE_SIZE);
489 if (table_start == -1UL)
490 panic("Cannot find space for the kernel page tables");
491
492 table_start >>= PAGE_SHIFT;
493 table_end = table_start;
494 table_top = table_start + (tables >> PAGE_SHIFT);
495
496 printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
497 end, table_start << PAGE_SHIFT, table_top << PAGE_SHIFT);
498 }
499
500 static void __init init_gbpages(void)
501 {
502 if (direct_gbpages && cpu_has_gbpages)
503 printk(KERN_INFO "Using GB pages for direct mapping\n");
504 else
505 direct_gbpages = 0;
506 }
507
508 static int is_kernel(unsigned long pfn)
509 {
510 unsigned long pg_addresss = pfn << PAGE_SHIFT;
511
512 if (pg_addresss >= (unsigned long) __pa(_text) &&
513 pg_addresss <= (unsigned long) __pa(_end))
514 return 1;
515
516 return 0;
517 }
518
519 static unsigned long __init kernel_physical_mapping_init(unsigned long start,
520 unsigned long end,
521 unsigned long page_size_mask)
522 {
523
524 unsigned long next, last_map_addr;
525 u64 cached_supported_pte_mask = __supported_pte_mask;
526 unsigned long cache_start = start;
527 unsigned long cache_end = end;
528
529 /*
530 * First iteration will setup identity mapping using large/small pages
531 * based on page_size_mask, with other attributes same as set by
532 * the early code in head_64.S
533 *
534 * Second iteration will setup the appropriate attributes
535 * as desired for the kernel identity mapping.
536 *
537 * This two pass mechanism conforms to the TLB app note which says:
538 *
539 * "Software should not write to a paging-structure entry in a way
540 * that would change, for any linear address, both the page size
541 * and either the page frame or attributes."
542 *
543 * For now, only difference between very early PTE attributes used in
544 * head_64.S and here is _PAGE_NX.
545 */
546 BUILD_BUG_ON((__PAGE_KERNEL_LARGE & ~__PAGE_KERNEL_IDENT_LARGE_EXEC)
547 != _PAGE_NX);
548 __supported_pte_mask &= ~(_PAGE_NX);
549 physical_mapping_iter = 1;
550
551 repeat:
552 last_map_addr = cache_end;
553
554 start = (unsigned long)__va(cache_start);
555 end = (unsigned long)__va(cache_end);
556
557 for (; start < end; start = next) {
558 pgd_t *pgd = pgd_offset_k(start);
559 unsigned long pud_phys;
560 pud_t *pud;
561
562 next = (start + PGDIR_SIZE) & PGDIR_MASK;
563 if (next > end)
564 next = end;
565
566 if (pgd_val(*pgd)) {
567 /*
568 * Static identity mappings will be overwritten
569 * with run-time mappings. For example, this allows
570 * the static 0-1GB identity mapping to be mapped
571 * non-executable with this.
572 */
573 if (is_kernel(pte_pfn(*((pte_t *) pgd))))
574 goto realloc;
575
576 last_map_addr = phys_pud_update(pgd, __pa(start),
577 __pa(end), page_size_mask);
578 continue;
579 }
580
581 realloc:
582 pud = alloc_low_page(&pud_phys);
583 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
584 page_size_mask);
585 unmap_low_page(pud);
586
587 spin_lock(&init_mm.page_table_lock);
588 pgd_populate(&init_mm, pgd, __va(pud_phys));
589 spin_unlock(&init_mm.page_table_lock);
590 }
591 __flush_tlb_all();
592
593 if (physical_mapping_iter == 1) {
594 physical_mapping_iter = 2;
595 /*
596 * Second iteration will set the actual desired PTE attributes.
597 */
598 __supported_pte_mask = cached_supported_pte_mask;
599 goto repeat;
600 }
601
602 return last_map_addr;
603 }
604
605 struct map_range {
606 unsigned long start;
607 unsigned long end;
608 unsigned page_size_mask;
609 };
610
611 #define NR_RANGE_MR 5
612
613 static int save_mr(struct map_range *mr, int nr_range,
614 unsigned long start_pfn, unsigned long end_pfn,
615 unsigned long page_size_mask)
616 {
617
618 if (start_pfn < end_pfn) {
619 if (nr_range >= NR_RANGE_MR)
620 panic("run out of range for init_memory_mapping\n");
621 mr[nr_range].start = start_pfn<<PAGE_SHIFT;
622 mr[nr_range].end = end_pfn<<PAGE_SHIFT;
623 mr[nr_range].page_size_mask = page_size_mask;
624 nr_range++;
625 }
626
627 return nr_range;
628 }
629
630 /*
631 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
632 * This runs before bootmem is initialized and gets pages directly from
633 * the physical memory. To access them they are temporarily mapped.
634 */
635 unsigned long __init_refok init_memory_mapping(unsigned long start,
636 unsigned long end)
637 {
638 unsigned long last_map_addr = 0;
639 unsigned long page_size_mask = 0;
640 unsigned long start_pfn, end_pfn;
641
642 struct map_range mr[NR_RANGE_MR];
643 int nr_range, i;
644 int use_pse, use_gbpages;
645
646 printk(KERN_INFO "init_memory_mapping\n");
647
648 /*
649 * Find space for the kernel direct mapping tables.
650 *
651 * Later we should allocate these tables in the local node of the
652 * memory mapped. Unfortunately this is done currently before the
653 * nodes are discovered.
654 */
655 if (!after_bootmem)
656 init_gbpages();
657
658 #ifdef CONFIG_DEBUG_PAGEALLOC
659 /*
660 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
661 * This will simplify cpa(), which otherwise needs to support splitting
662 * large pages into small in interrupt context, etc.
663 */
664 use_pse = use_gbpages = 0;
665 #else
666 use_pse = cpu_has_pse;
667 use_gbpages = direct_gbpages;
668 #endif
669
670 if (use_gbpages)
671 page_size_mask |= 1 << PG_LEVEL_1G;
672 if (use_pse)
673 page_size_mask |= 1 << PG_LEVEL_2M;
674
675 memset(mr, 0, sizeof(mr));
676 nr_range = 0;
677
678 /* head if not big page alignment ?*/
679 start_pfn = start >> PAGE_SHIFT;
680 end_pfn = ((start + (PMD_SIZE - 1)) >> PMD_SHIFT)
681 << (PMD_SHIFT - PAGE_SHIFT);
682 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
683
684 /* big page (2M) range*/
685 start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
686 << (PMD_SHIFT - PAGE_SHIFT);
687 end_pfn = ((start + (PUD_SIZE - 1))>>PUD_SHIFT)
688 << (PUD_SHIFT - PAGE_SHIFT);
689 if (end_pfn > ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT)))
690 end_pfn = ((end>>PUD_SHIFT)<<(PUD_SHIFT - PAGE_SHIFT));
691 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
692 page_size_mask & (1<<PG_LEVEL_2M));
693
694 /* big page (1G) range */
695 start_pfn = end_pfn;
696 end_pfn = (end>>PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
697 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
698 page_size_mask &
699 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
700
701 /* tail is not big page (1G) alignment */
702 start_pfn = end_pfn;
703 end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
704 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
705 page_size_mask & (1<<PG_LEVEL_2M));
706
707 /* tail is not big page (2M) alignment */
708 start_pfn = end_pfn;
709 end_pfn = end>>PAGE_SHIFT;
710 nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
711
712 /* try to merge same page size and continuous */
713 for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
714 unsigned long old_start;
715 if (mr[i].end != mr[i+1].start ||
716 mr[i].page_size_mask != mr[i+1].page_size_mask)
717 continue;
718 /* move it */
719 old_start = mr[i].start;
720 memmove(&mr[i], &mr[i+1],
721 (nr_range - 1 - i) * sizeof (struct map_range));
722 mr[i].start = old_start;
723 nr_range--;
724 }
725
726 for (i = 0; i < nr_range; i++)
727 printk(KERN_DEBUG " %010lx - %010lx page %s\n",
728 mr[i].start, mr[i].end,
729 (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
730 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
731
732 if (!after_bootmem)
733 find_early_table_space(end, use_pse, use_gbpages);
734
735 for (i = 0; i < nr_range; i++)
736 last_map_addr = kernel_physical_mapping_init(
737 mr[i].start, mr[i].end,
738 mr[i].page_size_mask);
739
740 if (!after_bootmem)
741 mmu_cr4_features = read_cr4();
742 __flush_tlb_all();
743
744 if (!after_bootmem && table_end > table_start)
745 reserve_early(table_start << PAGE_SHIFT,
746 table_end << PAGE_SHIFT, "PGTABLE");
747
748 printk(KERN_INFO "last_map_addr: %lx end: %lx\n",
749 last_map_addr, end);
750
751 if (!after_bootmem)
752 early_memtest(start, end);
753
754 return last_map_addr >> PAGE_SHIFT;
755 }
756
757 #ifndef CONFIG_NUMA
758 void __init initmem_init(unsigned long start_pfn, unsigned long end_pfn)
759 {
760 unsigned long bootmap_size, bootmap;
761
762 bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
763 bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size,
764 PAGE_SIZE);
765 if (bootmap == -1L)
766 panic("Cannot find bootmem map of size %ld\n", bootmap_size);
767 /* don't touch min_low_pfn */
768 bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
769 0, end_pfn);
770 e820_register_active_regions(0, start_pfn, end_pfn);
771 free_bootmem_with_active_regions(0, end_pfn);
772 early_res_to_bootmem(0, end_pfn<<PAGE_SHIFT);
773 reserve_bootmem(bootmap, bootmap_size, BOOTMEM_DEFAULT);
774 }
775
776 void __init paging_init(void)
777 {
778 unsigned long max_zone_pfns[MAX_NR_ZONES];
779
780 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
781 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
782 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
783 max_zone_pfns[ZONE_NORMAL] = max_pfn;
784
785 memory_present(0, 0, max_pfn);
786 sparse_init();
787 free_area_init_nodes(max_zone_pfns);
788 }
789 #endif
790
791 /*
792 * Memory hotplug specific functions
793 */
794 #ifdef CONFIG_MEMORY_HOTPLUG
795 /*
796 * Memory is added always to NORMAL zone. This means you will never get
797 * additional DMA/DMA32 memory.
798 */
799 int arch_add_memory(int nid, u64 start, u64 size)
800 {
801 struct pglist_data *pgdat = NODE_DATA(nid);
802 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
803 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
804 unsigned long nr_pages = size >> PAGE_SHIFT;
805 int ret;
806
807 last_mapped_pfn = init_memory_mapping(start, start + size-1);
808 if (last_mapped_pfn > max_pfn_mapped)
809 max_pfn_mapped = last_mapped_pfn;
810
811 ret = __add_pages(zone, start_pfn, nr_pages);
812 WARN_ON(1);
813
814 return ret;
815 }
816 EXPORT_SYMBOL_GPL(arch_add_memory);
817
818 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
819 int memory_add_physaddr_to_nid(u64 start)
820 {
821 return 0;
822 }
823 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
824 #endif
825
826 #endif /* CONFIG_MEMORY_HOTPLUG */
827
828 /*
829 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
830 * is valid. The argument is a physical page number.
831 *
832 *
833 * On x86, access has to be given to the first megabyte of ram because that area
834 * contains bios code and data regions used by X and dosemu and similar apps.
835 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
836 * mmio resources as well as potential bios/acpi data regions.
837 */
838 int devmem_is_allowed(unsigned long pagenr)
839 {
840 if (pagenr <= 256)
841 return 1;
842 if (!page_is_ram(pagenr))
843 return 1;
844 return 0;
845 }
846
847
848 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel,
849 kcore_modules, kcore_vsyscall;
850
851 void __init mem_init(void)
852 {
853 long codesize, reservedpages, datasize, initsize;
854
855 pci_iommu_alloc();
856
857 /* clear_bss() already clear the empty_zero_page */
858
859 reservedpages = 0;
860
861 /* this will put all low memory onto the freelists */
862 #ifdef CONFIG_NUMA
863 totalram_pages = numa_free_all_bootmem();
864 #else
865 totalram_pages = free_all_bootmem();
866 #endif
867 reservedpages = max_pfn - totalram_pages -
868 absent_pages_in_range(0, max_pfn);
869 after_bootmem = 1;
870
871 codesize = (unsigned long) &_etext - (unsigned long) &_text;
872 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
873 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
874
875 /* Register memory areas for /proc/kcore */
876 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
877 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
878 VMALLOC_END-VMALLOC_START);
879 kclist_add(&kcore_kernel, &_stext, _end - _stext);
880 kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
881 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
882 VSYSCALL_END - VSYSCALL_START);
883
884 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
885 "%ldk reserved, %ldk data, %ldk init)\n",
886 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
887 max_pfn << (PAGE_SHIFT-10),
888 codesize >> 10,
889 reservedpages << (PAGE_SHIFT-10),
890 datasize >> 10,
891 initsize >> 10);
892
893 cpa_init();
894 }
895
896 void free_init_pages(char *what, unsigned long begin, unsigned long end)
897 {
898 unsigned long addr = begin;
899
900 if (addr >= end)
901 return;
902
903 /*
904 * If debugging page accesses then do not free this memory but
905 * mark them not present - any buggy init-section access will
906 * create a kernel page fault:
907 */
908 #ifdef CONFIG_DEBUG_PAGEALLOC
909 printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
910 begin, PAGE_ALIGN(end));
911 set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
912 #else
913 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
914
915 for (; addr < end; addr += PAGE_SIZE) {
916 ClearPageReserved(virt_to_page(addr));
917 init_page_count(virt_to_page(addr));
918 memset((void *)(addr & ~(PAGE_SIZE-1)),
919 POISON_FREE_INITMEM, PAGE_SIZE);
920 free_page(addr);
921 totalram_pages++;
922 }
923 #endif
924 }
925
926 void free_initmem(void)
927 {
928 free_init_pages("unused kernel memory",
929 (unsigned long)(&__init_begin),
930 (unsigned long)(&__init_end));
931 }
932
933 #ifdef CONFIG_DEBUG_RODATA
934 const int rodata_test_data = 0xC3;
935 EXPORT_SYMBOL_GPL(rodata_test_data);
936
937 void mark_rodata_ro(void)
938 {
939 unsigned long start = PFN_ALIGN(_stext), end = PFN_ALIGN(__end_rodata);
940 unsigned long rodata_start =
941 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
942
943 #ifdef CONFIG_DYNAMIC_FTRACE
944 /* Dynamic tracing modifies the kernel text section */
945 start = rodata_start;
946 #endif
947
948 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
949 (end - start) >> 10);
950 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
951
952 /*
953 * The rodata section (but not the kernel text!) should also be
954 * not-executable.
955 */
956 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
957
958 rodata_test();
959
960 #ifdef CONFIG_CPA_DEBUG
961 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
962 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
963
964 printk(KERN_INFO "Testing CPA: again\n");
965 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
966 #endif
967 }
968
969 #endif
970
971 #ifdef CONFIG_BLK_DEV_INITRD
972 void free_initrd_mem(unsigned long start, unsigned long end)
973 {
974 free_init_pages("initrd memory", start, end);
975 }
976 #endif
977
978 int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
979 int flags)
980 {
981 #ifdef CONFIG_NUMA
982 int nid, next_nid;
983 int ret;
984 #endif
985 unsigned long pfn = phys >> PAGE_SHIFT;
986
987 if (pfn >= max_pfn) {
988 /*
989 * This can happen with kdump kernels when accessing
990 * firmware tables:
991 */
992 if (pfn < max_pfn_mapped)
993 return -EFAULT;
994
995 printk(KERN_ERR "reserve_bootmem: illegal reserve %lx %lu\n",
996 phys, len);
997 return -EFAULT;
998 }
999
1000 /* Should check here against the e820 map to avoid double free */
1001 #ifdef CONFIG_NUMA
1002 nid = phys_to_nid(phys);
1003 next_nid = phys_to_nid(phys + len - 1);
1004 if (nid == next_nid)
1005 ret = reserve_bootmem_node(NODE_DATA(nid), phys, len, flags);
1006 else
1007 ret = reserve_bootmem(phys, len, flags);
1008
1009 if (ret != 0)
1010 return ret;
1011
1012 #else
1013 reserve_bootmem(phys, len, BOOTMEM_DEFAULT);
1014 #endif
1015
1016 if (phys+len <= MAX_DMA_PFN*PAGE_SIZE) {
1017 dma_reserve += len / PAGE_SIZE;
1018 set_dma_reserve(dma_reserve);
1019 }
1020
1021 return 0;
1022 }
1023
1024 int kern_addr_valid(unsigned long addr)
1025 {
1026 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1027 pgd_t *pgd;
1028 pud_t *pud;
1029 pmd_t *pmd;
1030 pte_t *pte;
1031
1032 if (above != 0 && above != -1UL)
1033 return 0;
1034
1035 pgd = pgd_offset_k(addr);
1036 if (pgd_none(*pgd))
1037 return 0;
1038
1039 pud = pud_offset(pgd, addr);
1040 if (pud_none(*pud))
1041 return 0;
1042
1043 pmd = pmd_offset(pud, addr);
1044 if (pmd_none(*pmd))
1045 return 0;
1046
1047 if (pmd_large(*pmd))
1048 return pfn_valid(pmd_pfn(*pmd));
1049
1050 pte = pte_offset_kernel(pmd, addr);
1051 if (pte_none(*pte))
1052 return 0;
1053
1054 return pfn_valid(pte_pfn(*pte));
1055 }
1056
1057 /*
1058 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
1059 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1060 * not need special handling anymore:
1061 */
1062 static struct vm_area_struct gate_vma = {
1063 .vm_start = VSYSCALL_START,
1064 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
1065 .vm_page_prot = PAGE_READONLY_EXEC,
1066 .vm_flags = VM_READ | VM_EXEC
1067 };
1068
1069 struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
1070 {
1071 #ifdef CONFIG_IA32_EMULATION
1072 if (test_tsk_thread_flag(tsk, TIF_IA32))
1073 return NULL;
1074 #endif
1075 return &gate_vma;
1076 }
1077
1078 int in_gate_area(struct task_struct *task, unsigned long addr)
1079 {
1080 struct vm_area_struct *vma = get_gate_vma(task);
1081
1082 if (!vma)
1083 return 0;
1084
1085 return (addr >= vma->vm_start) && (addr < vma->vm_end);
1086 }
1087
1088 /*
1089 * Use this when you have no reliable task/vma, typically from interrupt
1090 * context. It is less reliable than using the task's vma and may give
1091 * false positives:
1092 */
1093 int in_gate_area_no_task(unsigned long addr)
1094 {
1095 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
1096 }
1097
1098 const char *arch_vma_name(struct vm_area_struct *vma)
1099 {
1100 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
1101 return "[vdso]";
1102 if (vma == &gate_vma)
1103 return "[vsyscall]";
1104 return NULL;
1105 }
1106
1107 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1108 /*
1109 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1110 */
1111 static long __meminitdata addr_start, addr_end;
1112 static void __meminitdata *p_start, *p_end;
1113 static int __meminitdata node_start;
1114
1115 int __meminit
1116 vmemmap_populate(struct page *start_page, unsigned long size, int node)
1117 {
1118 unsigned long addr = (unsigned long)start_page;
1119 unsigned long end = (unsigned long)(start_page + size);
1120 unsigned long next;
1121 pgd_t *pgd;
1122 pud_t *pud;
1123 pmd_t *pmd;
1124
1125 for (; addr < end; addr = next) {
1126 void *p = NULL;
1127
1128 pgd = vmemmap_pgd_populate(addr, node);
1129 if (!pgd)
1130 return -ENOMEM;
1131
1132 pud = vmemmap_pud_populate(pgd, addr, node);
1133 if (!pud)
1134 return -ENOMEM;
1135
1136 if (!cpu_has_pse) {
1137 next = (addr + PAGE_SIZE) & PAGE_MASK;
1138 pmd = vmemmap_pmd_populate(pud, addr, node);
1139
1140 if (!pmd)
1141 return -ENOMEM;
1142
1143 p = vmemmap_pte_populate(pmd, addr, node);
1144
1145 if (!p)
1146 return -ENOMEM;
1147
1148 addr_end = addr + PAGE_SIZE;
1149 p_end = p + PAGE_SIZE;
1150 } else {
1151 next = pmd_addr_end(addr, end);
1152
1153 pmd = pmd_offset(pud, addr);
1154 if (pmd_none(*pmd)) {
1155 pte_t entry;
1156
1157 p = vmemmap_alloc_block(PMD_SIZE, node);
1158 if (!p)
1159 return -ENOMEM;
1160
1161 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1162 PAGE_KERNEL_LARGE);
1163 set_pmd(pmd, __pmd(pte_val(entry)));
1164
1165 /* check to see if we have contiguous blocks */
1166 if (p_end != p || node_start != node) {
1167 if (p_start)
1168 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1169 addr_start, addr_end-1, p_start, p_end-1, node_start);
1170 addr_start = addr;
1171 node_start = node;
1172 p_start = p;
1173 }
1174
1175 addr_end = addr + PMD_SIZE;
1176 p_end = p + PMD_SIZE;
1177 } else
1178 vmemmap_verify((pte_t *)pmd, node, addr, next);
1179 }
1180
1181 }
1182 return 0;
1183 }
1184
1185 void __meminit vmemmap_populate_print_last(void)
1186 {
1187 if (p_start) {
1188 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1189 addr_start, addr_end-1, p_start, p_end-1, node_start);
1190 p_start = NULL;
1191 p_end = NULL;
1192 node_start = 0;
1193 }
1194 }
1195 #endif
Support for the Chinese Samsung S3C2440 based development boards