2 * linux/arch/x86_64/mm/init.c
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>
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>
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>
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>
39 #include <asm/fixmap.h>
43 #include <asm/mmu_context.h>
44 #include <asm/proto.h>
46 #include <asm/sections.h>
47 #include <asm/kdebug.h>
49 #include <asm/cacheflush.h>
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.
56 unsigned long max_low_pfn_mapped
;
57 unsigned long max_pfn_mapped
;
59 static unsigned long dma_reserve __initdata
;
61 DEFINE_PER_CPU(struct mmu_gather
, mmu_gathers
);
64 #ifdef CONFIG_DIRECT_GBPAGES
69 static int __init
parse_direct_gbpages_off(char *arg
)
74 early_param("nogbpages", parse_direct_gbpages_off
);
76 static int __init
parse_direct_gbpages_on(char *arg
)
81 early_param("gbpages", parse_direct_gbpages_on
);
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.
91 unsigned long __supported_pte_mask __read_mostly
= ~0UL;
92 EXPORT_SYMBOL_GPL(__supported_pte_mask
);
94 static int do_not_nx __cpuinitdata
;
98 * Control non-executable mappings for 64-bit processes.
100 * on Enable (default)
103 static int __init
nonx_setup(char *str
)
107 if (!strncmp(str
, "on", 2)) {
108 __supported_pte_mask
|= _PAGE_NX
;
110 } else if (!strncmp(str
, "off", 3)) {
112 __supported_pte_mask
&= ~_PAGE_NX
;
116 early_param("noexec", nonx_setup
);
118 void __cpuinit
check_efer(void)
122 rdmsrl(MSR_EFER
, efer
);
123 if (!(efer
& EFER_NX
) || do_not_nx
)
124 __supported_pte_mask
&= ~_PAGE_NX
;
127 int force_personality32
;
131 * Control non executable heap for 32bit processes.
132 * To control the stack too use noexec=off
134 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
135 * off PROT_READ implies PROT_EXEC
137 static int __init
nonx32_setup(char *str
)
139 if (!strcmp(str
, "on"))
140 force_personality32
&= ~READ_IMPLIES_EXEC
;
141 else if (!strcmp(str
, "off"))
142 force_personality32
|= READ_IMPLIES_EXEC
;
145 __setup("noexec32=", nonx32_setup
);
148 * NOTE: This function is marked __ref because it calls __init function
149 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
151 static __ref
void *spp_getpage(void)
156 ptr
= (void *) get_zeroed_page(GFP_ATOMIC
);
158 ptr
= alloc_bootmem_pages(PAGE_SIZE
);
160 if (!ptr
|| ((unsigned long)ptr
& ~PAGE_MASK
)) {
161 panic("set_pte_phys: cannot allocate page data %s\n",
162 after_bootmem
? "after bootmem" : "");
165 pr_debug("spp_getpage %p\n", ptr
);
171 set_pte_vaddr_pud(pud_t
*pud_page
, unsigned long vaddr
, pte_t new_pte
)
177 pud
= pud_page
+ pud_index(vaddr
);
178 if (pud_none(*pud
)) {
179 pmd
= (pmd_t
*) spp_getpage();
180 pud_populate(&init_mm
, pud
, pmd
);
181 if (pmd
!= pmd_offset(pud
, 0)) {
182 printk(KERN_ERR
"PAGETABLE BUG #01! %p <-> %p\n",
183 pmd
, pmd_offset(pud
, 0));
187 pmd
= pmd_offset(pud
, vaddr
);
188 if (pmd_none(*pmd
)) {
189 pte
= (pte_t
*) spp_getpage();
190 pmd_populate_kernel(&init_mm
, pmd
, pte
);
191 if (pte
!= pte_offset_kernel(pmd
, 0)) {
192 printk(KERN_ERR
"PAGETABLE BUG #02!\n");
197 pte
= pte_offset_kernel(pmd
, vaddr
);
198 if (!pte_none(*pte
) && pte_val(new_pte
) &&
199 pte_val(*pte
) != (pte_val(new_pte
) & __supported_pte_mask
))
201 set_pte(pte
, new_pte
);
204 * It's enough to flush this one mapping.
205 * (PGE mappings get flushed as well)
207 __flush_tlb_one(vaddr
);
211 set_pte_vaddr(unsigned long vaddr
, pte_t pteval
)
216 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr
, native_pte_val(pteval
));
218 pgd
= pgd_offset_k(vaddr
);
219 if (pgd_none(*pgd
)) {
221 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
224 pud_page
= (pud_t
*)pgd_page_vaddr(*pgd
);
225 set_pte_vaddr_pud(pud_page
, vaddr
, pteval
);
229 * Create large page table mappings for a range of physical addresses.
231 static void __init
__init_extra_mapping(unsigned long phys
, unsigned long size
,
238 BUG_ON((phys
& ~PMD_MASK
) || (size
& ~PMD_MASK
));
239 for (; size
; phys
+= PMD_SIZE
, size
-= PMD_SIZE
) {
240 pgd
= pgd_offset_k((unsigned long)__va(phys
));
241 if (pgd_none(*pgd
)) {
242 pud
= (pud_t
*) spp_getpage();
243 set_pgd(pgd
, __pgd(__pa(pud
) | _KERNPG_TABLE
|
246 pud
= pud_offset(pgd
, (unsigned long)__va(phys
));
247 if (pud_none(*pud
)) {
248 pmd
= (pmd_t
*) spp_getpage();
249 set_pud(pud
, __pud(__pa(pmd
) | _KERNPG_TABLE
|
252 pmd
= pmd_offset(pud
, phys
);
253 BUG_ON(!pmd_none(*pmd
));
254 set_pmd(pmd
, __pmd(phys
| pgprot_val(prot
)));
258 void __init
init_extra_mapping_wb(unsigned long phys
, unsigned long size
)
260 __init_extra_mapping(phys
, size
, PAGE_KERNEL_LARGE
);
263 void __init
init_extra_mapping_uc(unsigned long phys
, unsigned long size
)
265 __init_extra_mapping(phys
, size
, PAGE_KERNEL_LARGE_NOCACHE
);
269 * The head.S code sets up the kernel high mapping:
271 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
273 * phys_addr holds the negative offset to the kernel, which is added
274 * to the compile time generated pmds. This results in invalid pmds up
275 * to the point where we hit the physaddr 0 mapping.
277 * We limit the mappings to the region from _text to _end. _end is
278 * rounded up to the 2MB boundary. This catches the invalid pmds as
279 * well, as they are located before _text:
281 void __init
cleanup_highmap(void)
283 unsigned long vaddr
= __START_KERNEL_map
;
284 unsigned long end
= roundup((unsigned long)_end
, PMD_SIZE
) - 1;
285 pmd_t
*pmd
= level2_kernel_pgt
;
286 pmd_t
*last_pmd
= pmd
+ PTRS_PER_PMD
;
288 for (; pmd
< last_pmd
; pmd
++, vaddr
+= PMD_SIZE
) {
291 if (vaddr
< (unsigned long) _text
|| vaddr
> end
)
292 set_pmd(pmd
, __pmd(0));
296 static unsigned long __initdata table_start
;
297 static unsigned long __meminitdata table_end
;
298 static unsigned long __meminitdata table_top
;
300 static __ref
void *alloc_low_page(unsigned long *phys
)
302 unsigned long pfn
= table_end
++;
306 adr
= (void *)get_zeroed_page(GFP_ATOMIC
);
312 if (pfn
>= table_top
)
313 panic("alloc_low_page: ran out of memory");
315 adr
= early_ioremap(pfn
* PAGE_SIZE
, PAGE_SIZE
);
316 memset(adr
, 0, PAGE_SIZE
);
317 *phys
= pfn
* PAGE_SIZE
;
321 static __ref
void unmap_low_page(void *adr
)
326 early_iounmap(adr
, PAGE_SIZE
);
329 static unsigned long __meminit
330 phys_pte_init(pte_t
*pte_page
, unsigned long addr
, unsigned long end
,
334 unsigned long last_map_addr
= end
;
337 pte_t
*pte
= pte_page
+ pte_index(addr
);
339 for(i
= pte_index(addr
); i
< PTRS_PER_PTE
; i
++, addr
+= PAGE_SIZE
, pte
++) {
342 if (!after_bootmem
) {
343 for(; i
< PTRS_PER_PTE
; i
++, pte
++)
344 set_pte(pte
, __pte(0));
350 * We will re-use the existing mapping.
351 * Xen for example has some special requirements, like mapping
352 * pagetable pages as RO. So assume someone who pre-setup
353 * these mappings are more intelligent.
359 printk(" pte=%p addr=%lx pte=%016lx\n",
360 pte
, addr
, pfn_pte(addr
>> PAGE_SHIFT
, PAGE_KERNEL
).pte
);
362 set_pte(pte
, pfn_pte(addr
>> PAGE_SHIFT
, prot
));
363 last_map_addr
= (addr
& PAGE_MASK
) + PAGE_SIZE
;
366 update_page_count(PG_LEVEL_4K
, pages
);
368 return last_map_addr
;
371 static unsigned long __meminit
372 phys_pte_update(pmd_t
*pmd
, unsigned long address
, unsigned long end
,
375 pte_t
*pte
= (pte_t
*)pmd_page_vaddr(*pmd
);
377 return phys_pte_init(pte
, address
, end
, prot
);
380 static unsigned long __meminit
381 phys_pmd_init(pmd_t
*pmd_page
, unsigned long address
, unsigned long end
,
382 unsigned long page_size_mask
, pgprot_t prot
)
384 unsigned long pages
= 0;
385 unsigned long last_map_addr
= end
;
387 int i
= pmd_index(address
);
389 for (; i
< PTRS_PER_PMD
; i
++, address
+= PMD_SIZE
) {
390 unsigned long pte_phys
;
391 pmd_t
*pmd
= pmd_page
+ pmd_index(address
);
393 pgprot_t new_prot
= prot
;
395 if (address
>= end
) {
396 if (!after_bootmem
) {
397 for (; i
< PTRS_PER_PMD
; i
++, pmd
++)
398 set_pmd(pmd
, __pmd(0));
404 if (!pmd_large(*pmd
)) {
405 spin_lock(&init_mm
.page_table_lock
);
406 last_map_addr
= phys_pte_update(pmd
, address
,
408 spin_unlock(&init_mm
.page_table_lock
);
412 * If we are ok with PG_LEVEL_2M mapping, then we will
413 * use the existing mapping,
415 * Otherwise, we will split the large page mapping but
416 * use the same existing protection bits except for
417 * large page, so that we don't violate Intel's TLB
418 * Application note (317080) which says, while changing
419 * the page sizes, new and old translations should
420 * not differ with respect to page frame and
423 if (page_size_mask
& (1 << PG_LEVEL_2M
))
425 new_prot
= pte_pgprot(pte_clrhuge(*(pte_t
*)pmd
));
428 if (page_size_mask
& (1<<PG_LEVEL_2M
)) {
430 spin_lock(&init_mm
.page_table_lock
);
431 set_pte((pte_t
*)pmd
,
432 pfn_pte(address
>> PAGE_SHIFT
,
433 __pgprot(pgprot_val(prot
) | _PAGE_PSE
)));
434 spin_unlock(&init_mm
.page_table_lock
);
435 last_map_addr
= (address
& PMD_MASK
) + PMD_SIZE
;
439 pte
= alloc_low_page(&pte_phys
);
440 last_map_addr
= phys_pte_init(pte
, address
, end
, new_prot
);
443 spin_lock(&init_mm
.page_table_lock
);
444 pmd_populate_kernel(&init_mm
, pmd
, __va(pte_phys
));
445 spin_unlock(&init_mm
.page_table_lock
);
447 update_page_count(PG_LEVEL_2M
, pages
);
448 return last_map_addr
;
451 static unsigned long __meminit
452 phys_pmd_update(pud_t
*pud
, unsigned long address
, unsigned long end
,
453 unsigned long page_size_mask
, pgprot_t prot
)
455 pmd_t
*pmd
= pmd_offset(pud
, 0);
456 unsigned long last_map_addr
;
458 last_map_addr
= phys_pmd_init(pmd
, address
, end
, page_size_mask
, prot
);
460 return last_map_addr
;
463 static unsigned long __meminit
464 phys_pud_init(pud_t
*pud_page
, unsigned long addr
, unsigned long end
,
465 unsigned long page_size_mask
)
467 unsigned long pages
= 0;
468 unsigned long last_map_addr
= end
;
469 int i
= pud_index(addr
);
471 for (; i
< PTRS_PER_PUD
; i
++, addr
= (addr
& PUD_MASK
) + PUD_SIZE
) {
472 unsigned long pmd_phys
;
473 pud_t
*pud
= pud_page
+ pud_index(addr
);
475 pgprot_t prot
= PAGE_KERNEL
;
480 if (!after_bootmem
&&
481 !e820_any_mapped(addr
, addr
+PUD_SIZE
, 0)) {
482 set_pud(pud
, __pud(0));
487 if (!pud_large(*pud
)) {
488 last_map_addr
= phys_pmd_update(pud
, addr
, end
,
489 page_size_mask
, prot
);
493 * If we are ok with PG_LEVEL_1G mapping, then we will
494 * use the existing mapping.
496 * Otherwise, we will split the gbpage mapping but use
497 * the same existing protection bits except for large
498 * page, so that we don't violate Intel's TLB
499 * Application note (317080) which says, while changing
500 * the page sizes, new and old translations should
501 * not differ with respect to page frame and
504 if (page_size_mask
& (1 << PG_LEVEL_1G
))
506 prot
= pte_pgprot(pte_clrhuge(*(pte_t
*)pud
));
509 if (page_size_mask
& (1<<PG_LEVEL_1G
)) {
511 spin_lock(&init_mm
.page_table_lock
);
512 set_pte((pte_t
*)pud
,
513 pfn_pte(addr
>> PAGE_SHIFT
, PAGE_KERNEL_LARGE
));
514 spin_unlock(&init_mm
.page_table_lock
);
515 last_map_addr
= (addr
& PUD_MASK
) + PUD_SIZE
;
519 pmd
= alloc_low_page(&pmd_phys
);
520 last_map_addr
= phys_pmd_init(pmd
, addr
, end
, page_size_mask
,
524 spin_lock(&init_mm
.page_table_lock
);
525 pud_populate(&init_mm
, pud
, __va(pmd_phys
));
526 spin_unlock(&init_mm
.page_table_lock
);
530 update_page_count(PG_LEVEL_1G
, pages
);
532 return last_map_addr
;
535 static unsigned long __meminit
536 phys_pud_update(pgd_t
*pgd
, unsigned long addr
, unsigned long end
,
537 unsigned long page_size_mask
)
541 pud
= (pud_t
*)pgd_page_vaddr(*pgd
);
543 return phys_pud_init(pud
, addr
, end
, page_size_mask
);
546 static void __init
find_early_table_space(unsigned long end
, int use_pse
,
549 unsigned long puds
, pmds
, ptes
, tables
, start
;
551 puds
= (end
+ PUD_SIZE
- 1) >> PUD_SHIFT
;
552 tables
= roundup(puds
* sizeof(pud_t
), PAGE_SIZE
);
555 extra
= end
- ((end
>>PUD_SHIFT
) << PUD_SHIFT
);
556 pmds
= (extra
+ PMD_SIZE
- 1) >> PMD_SHIFT
;
558 pmds
= (end
+ PMD_SIZE
- 1) >> PMD_SHIFT
;
559 tables
+= roundup(pmds
* sizeof(pmd_t
), PAGE_SIZE
);
563 extra
= end
- ((end
>>PMD_SHIFT
) << PMD_SHIFT
);
564 ptes
= (extra
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
566 ptes
= (end
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
567 tables
+= roundup(ptes
* sizeof(pte_t
), PAGE_SIZE
);
570 * RED-PEN putting page tables only on node 0 could
571 * cause a hotspot and fill up ZONE_DMA. The page tables
572 * need roughly 0.5KB per GB.
575 table_start
= find_e820_area(start
, end
, tables
, PAGE_SIZE
);
576 if (table_start
== -1UL)
577 panic("Cannot find space for the kernel page tables");
579 table_start
>>= PAGE_SHIFT
;
580 table_end
= table_start
;
581 table_top
= table_start
+ (tables
>> PAGE_SHIFT
);
583 printk(KERN_DEBUG
"kernel direct mapping tables up to %lx @ %lx-%lx\n",
584 end
, table_start
<< PAGE_SHIFT
, table_top
<< PAGE_SHIFT
);
587 static void __init
init_gbpages(void)
589 if (direct_gbpages
&& cpu_has_gbpages
)
590 printk(KERN_INFO
"Using GB pages for direct mapping\n");
595 static unsigned long __init
kernel_physical_mapping_init(unsigned long start
,
597 unsigned long page_size_mask
)
600 unsigned long next
, last_map_addr
= end
;
602 start
= (unsigned long)__va(start
);
603 end
= (unsigned long)__va(end
);
605 for (; start
< end
; start
= next
) {
606 pgd_t
*pgd
= pgd_offset_k(start
);
607 unsigned long pud_phys
;
610 next
= (start
+ PGDIR_SIZE
) & PGDIR_MASK
;
615 last_map_addr
= phys_pud_update(pgd
, __pa(start
),
616 __pa(end
), page_size_mask
);
620 pud
= alloc_low_page(&pud_phys
);
621 last_map_addr
= phys_pud_init(pud
, __pa(start
), __pa(next
),
625 spin_lock(&init_mm
.page_table_lock
);
626 pgd_populate(&init_mm
, pgd
, __va(pud_phys
));
627 spin_unlock(&init_mm
.page_table_lock
);
631 return last_map_addr
;
637 unsigned page_size_mask
;
640 #define NR_RANGE_MR 5
642 static int save_mr(struct map_range
*mr
, int nr_range
,
643 unsigned long start_pfn
, unsigned long end_pfn
,
644 unsigned long page_size_mask
)
647 if (start_pfn
< end_pfn
) {
648 if (nr_range
>= NR_RANGE_MR
)
649 panic("run out of range for init_memory_mapping\n");
650 mr
[nr_range
].start
= start_pfn
<<PAGE_SHIFT
;
651 mr
[nr_range
].end
= end_pfn
<<PAGE_SHIFT
;
652 mr
[nr_range
].page_size_mask
= page_size_mask
;
660 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
661 * This runs before bootmem is initialized and gets pages directly from
662 * the physical memory. To access them they are temporarily mapped.
664 unsigned long __init_refok
init_memory_mapping(unsigned long start
,
667 unsigned long last_map_addr
= 0;
668 unsigned long page_size_mask
= 0;
669 unsigned long start_pfn
, end_pfn
;
671 struct map_range mr
[NR_RANGE_MR
];
673 int use_pse
, use_gbpages
;
675 printk(KERN_INFO
"init_memory_mapping\n");
678 * Find space for the kernel direct mapping tables.
680 * Later we should allocate these tables in the local node of the
681 * memory mapped. Unfortunately this is done currently before the
682 * nodes are discovered.
687 #ifdef CONFIG_DEBUG_PAGEALLOC
689 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
690 * This will simplify cpa(), which otherwise needs to support splitting
691 * large pages into small in interrupt context, etc.
693 use_pse
= use_gbpages
= 0;
695 use_pse
= cpu_has_pse
;
696 use_gbpages
= direct_gbpages
;
700 page_size_mask
|= 1 << PG_LEVEL_1G
;
702 page_size_mask
|= 1 << PG_LEVEL_2M
;
704 memset(mr
, 0, sizeof(mr
));
707 /* head if not big page alignment ?*/
708 start_pfn
= start
>> PAGE_SHIFT
;
709 end_pfn
= ((start
+ (PMD_SIZE
- 1)) >> PMD_SHIFT
)
710 << (PMD_SHIFT
- PAGE_SHIFT
);
711 nr_range
= save_mr(mr
, nr_range
, start_pfn
, end_pfn
, 0);
713 /* big page (2M) range*/
714 start_pfn
= ((start
+ (PMD_SIZE
- 1))>>PMD_SHIFT
)
715 << (PMD_SHIFT
- PAGE_SHIFT
);
716 end_pfn
= ((start
+ (PUD_SIZE
- 1))>>PUD_SHIFT
)
717 << (PUD_SHIFT
- PAGE_SHIFT
);
718 if (end_pfn
> ((end
>>PUD_SHIFT
)<<(PUD_SHIFT
- PAGE_SHIFT
)))
719 end_pfn
= ((end
>>PUD_SHIFT
)<<(PUD_SHIFT
- PAGE_SHIFT
));
720 nr_range
= save_mr(mr
, nr_range
, start_pfn
, end_pfn
,
721 page_size_mask
& (1<<PG_LEVEL_2M
));
723 /* big page (1G) range */
725 end_pfn
= (end
>>PUD_SHIFT
) << (PUD_SHIFT
- PAGE_SHIFT
);
726 nr_range
= save_mr(mr
, nr_range
, start_pfn
, end_pfn
,
728 ((1<<PG_LEVEL_2M
)|(1<<PG_LEVEL_1G
)));
730 /* tail is not big page (1G) alignment */
732 end_pfn
= (end
>>PMD_SHIFT
) << (PMD_SHIFT
- PAGE_SHIFT
);
733 nr_range
= save_mr(mr
, nr_range
, start_pfn
, end_pfn
,
734 page_size_mask
& (1<<PG_LEVEL_2M
));
736 /* tail is not big page (2M) alignment */
738 end_pfn
= end
>>PAGE_SHIFT
;
739 nr_range
= save_mr(mr
, nr_range
, start_pfn
, end_pfn
, 0);
741 /* try to merge same page size and continuous */
742 for (i
= 0; nr_range
> 1 && i
< nr_range
- 1; i
++) {
743 unsigned long old_start
;
744 if (mr
[i
].end
!= mr
[i
+1].start
||
745 mr
[i
].page_size_mask
!= mr
[i
+1].page_size_mask
)
748 old_start
= mr
[i
].start
;
749 memmove(&mr
[i
], &mr
[i
+1],
750 (nr_range
- 1 - i
) * sizeof (struct map_range
));
751 mr
[i
].start
= old_start
;
755 for (i
= 0; i
< nr_range
; i
++)
756 printk(KERN_DEBUG
" %010lx - %010lx page %s\n",
757 mr
[i
].start
, mr
[i
].end
,
758 (mr
[i
].page_size_mask
& (1<<PG_LEVEL_1G
))?"1G":(
759 (mr
[i
].page_size_mask
& (1<<PG_LEVEL_2M
))?"2M":"4k"));
762 find_early_table_space(end
, use_pse
, use_gbpages
);
764 for (i
= 0; i
< nr_range
; i
++)
765 last_map_addr
= kernel_physical_mapping_init(
766 mr
[i
].start
, mr
[i
].end
,
767 mr
[i
].page_size_mask
);
770 mmu_cr4_features
= read_cr4();
773 if (!after_bootmem
&& table_end
> table_start
)
774 reserve_early(table_start
<< PAGE_SHIFT
,
775 table_end
<< PAGE_SHIFT
, "PGTABLE");
777 printk(KERN_INFO
"last_map_addr: %lx end: %lx\n",
781 early_memtest(start
, end
);
783 return last_map_addr
>> PAGE_SHIFT
;
787 void __init
initmem_init(unsigned long start_pfn
, unsigned long end_pfn
)
789 unsigned long bootmap_size
, bootmap
;
791 bootmap_size
= bootmem_bootmap_pages(end_pfn
)<<PAGE_SHIFT
;
792 bootmap
= find_e820_area(0, end_pfn
<<PAGE_SHIFT
, bootmap_size
,
795 panic("Cannot find bootmem map of size %ld\n", bootmap_size
);
796 /* don't touch min_low_pfn */
797 bootmap_size
= init_bootmem_node(NODE_DATA(0), bootmap
>> PAGE_SHIFT
,
799 e820_register_active_regions(0, start_pfn
, end_pfn
);
800 free_bootmem_with_active_regions(0, end_pfn
);
801 early_res_to_bootmem(0, end_pfn
<<PAGE_SHIFT
);
802 reserve_bootmem(bootmap
, bootmap_size
, BOOTMEM_DEFAULT
);
805 void __init
paging_init(void)
807 unsigned long max_zone_pfns
[MAX_NR_ZONES
];
809 memset(max_zone_pfns
, 0, sizeof(max_zone_pfns
));
810 max_zone_pfns
[ZONE_DMA
] = MAX_DMA_PFN
;
811 max_zone_pfns
[ZONE_DMA32
] = MAX_DMA32_PFN
;
812 max_zone_pfns
[ZONE_NORMAL
] = max_pfn
;
814 memory_present(0, 0, max_pfn
);
816 free_area_init_nodes(max_zone_pfns
);
821 * Memory hotplug specific functions
823 #ifdef CONFIG_MEMORY_HOTPLUG
825 * Memory is added always to NORMAL zone. This means you will never get
826 * additional DMA/DMA32 memory.
828 int arch_add_memory(int nid
, u64 start
, u64 size
)
830 struct pglist_data
*pgdat
= NODE_DATA(nid
);
831 struct zone
*zone
= pgdat
->node_zones
+ ZONE_NORMAL
;
832 unsigned long last_mapped_pfn
, start_pfn
= start
>> PAGE_SHIFT
;
833 unsigned long nr_pages
= size
>> PAGE_SHIFT
;
836 last_mapped_pfn
= init_memory_mapping(start
, start
+ size
-1);
837 if (last_mapped_pfn
> max_pfn_mapped
)
838 max_pfn_mapped
= last_mapped_pfn
;
840 ret
= __add_pages(zone
, start_pfn
, nr_pages
);
845 EXPORT_SYMBOL_GPL(arch_add_memory
);
847 #if !defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA)
848 int memory_add_physaddr_to_nid(u64 start
)
852 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid
);
855 #endif /* CONFIG_MEMORY_HOTPLUG */
858 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
859 * is valid. The argument is a physical page number.
862 * On x86, access has to be given to the first megabyte of ram because that area
863 * contains bios code and data regions used by X and dosemu and similar apps.
864 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
865 * mmio resources as well as potential bios/acpi data regions.
867 int devmem_is_allowed(unsigned long pagenr
)
871 if (!page_is_ram(pagenr
))
877 static struct kcore_list kcore_mem
, kcore_vmalloc
, kcore_kernel
,
878 kcore_modules
, kcore_vsyscall
;
880 void __init
mem_init(void)
882 long codesize
, reservedpages
, datasize
, initsize
;
886 /* clear_bss() already clear the empty_zero_page */
890 /* this will put all low memory onto the freelists */
892 totalram_pages
= numa_free_all_bootmem();
894 totalram_pages
= free_all_bootmem();
896 reservedpages
= max_pfn
- totalram_pages
-
897 absent_pages_in_range(0, max_pfn
);
900 codesize
= (unsigned long) &_etext
- (unsigned long) &_text
;
901 datasize
= (unsigned long) &_edata
- (unsigned long) &_etext
;
902 initsize
= (unsigned long) &__init_end
- (unsigned long) &__init_begin
;
904 /* Register memory areas for /proc/kcore */
905 kclist_add(&kcore_mem
, __va(0), max_low_pfn
<< PAGE_SHIFT
);
906 kclist_add(&kcore_vmalloc
, (void *)VMALLOC_START
,
907 VMALLOC_END
-VMALLOC_START
);
908 kclist_add(&kcore_kernel
, &_stext
, _end
- _stext
);
909 kclist_add(&kcore_modules
, (void *)MODULES_VADDR
, MODULES_LEN
);
910 kclist_add(&kcore_vsyscall
, (void *)VSYSCALL_START
,
911 VSYSCALL_END
- VSYSCALL_START
);
913 printk(KERN_INFO
"Memory: %luk/%luk available (%ldk kernel code, "
914 "%ldk reserved, %ldk data, %ldk init)\n",
915 (unsigned long) nr_free_pages() << (PAGE_SHIFT
-10),
916 max_pfn
<< (PAGE_SHIFT
-10),
918 reservedpages
<< (PAGE_SHIFT
-10),
923 void free_init_pages(char *what
, unsigned long begin
, unsigned long end
)
925 unsigned long addr
= begin
;
931 * If debugging page accesses then do not free this memory but
932 * mark them not present - any buggy init-section access will
933 * create a kernel page fault:
935 #ifdef CONFIG_DEBUG_PAGEALLOC
936 printk(KERN_INFO
"debug: unmapping init memory %08lx..%08lx\n",
937 begin
, PAGE_ALIGN(end
));
938 set_memory_np(begin
, (end
- begin
) >> PAGE_SHIFT
);
940 printk(KERN_INFO
"Freeing %s: %luk freed\n", what
, (end
- begin
) >> 10);
942 for (; addr
< end
; addr
+= PAGE_SIZE
) {
943 ClearPageReserved(virt_to_page(addr
));
944 init_page_count(virt_to_page(addr
));
945 memset((void *)(addr
& ~(PAGE_SIZE
-1)),
946 POISON_FREE_INITMEM
, PAGE_SIZE
);
953 void free_initmem(void)
955 free_init_pages("unused kernel memory",
956 (unsigned long)(&__init_begin
),
957 (unsigned long)(&__init_end
));
960 #ifdef CONFIG_DEBUG_RODATA
961 const int rodata_test_data
= 0xC3;
962 EXPORT_SYMBOL_GPL(rodata_test_data
);
964 void mark_rodata_ro(void)
966 unsigned long start
= PFN_ALIGN(_stext
), end
= PFN_ALIGN(__end_rodata
);
967 unsigned long rodata_start
=
968 ((unsigned long)__start_rodata
+ PAGE_SIZE
- 1) & PAGE_MASK
;
970 #ifdef CONFIG_DYNAMIC_FTRACE
971 /* Dynamic tracing modifies the kernel text section */
972 start
= rodata_start
;
975 printk(KERN_INFO
"Write protecting the kernel read-only data: %luk\n",
976 (end
- start
) >> 10);
977 set_memory_ro(start
, (end
- start
) >> PAGE_SHIFT
);
980 * The rodata section (but not the kernel text!) should also be
983 set_memory_nx(rodata_start
, (end
- rodata_start
) >> PAGE_SHIFT
);
987 #ifdef CONFIG_CPA_DEBUG
988 printk(KERN_INFO
"Testing CPA: undo %lx-%lx\n", start
, end
);
989 set_memory_rw(start
, (end
-start
) >> PAGE_SHIFT
);
991 printk(KERN_INFO
"Testing CPA: again\n");
992 set_memory_ro(start
, (end
-start
) >> PAGE_SHIFT
);
998 #ifdef CONFIG_BLK_DEV_INITRD
999 void free_initrd_mem(unsigned long start
, unsigned long end
)
1001 free_init_pages("initrd memory", start
, end
);
1005 int __init
reserve_bootmem_generic(unsigned long phys
, unsigned long len
,
1012 unsigned long pfn
= phys
>> PAGE_SHIFT
;
1014 if (pfn
>= max_pfn
) {
1016 * This can happen with kdump kernels when accessing
1019 if (pfn
< max_pfn_mapped
)
1022 printk(KERN_ERR
"reserve_bootmem: illegal reserve %lx %lu\n",
1027 /* Should check here against the e820 map to avoid double free */
1029 nid
= phys_to_nid(phys
);
1030 next_nid
= phys_to_nid(phys
+ len
- 1);
1031 if (nid
== next_nid
)
1032 ret
= reserve_bootmem_node(NODE_DATA(nid
), phys
, len
, flags
);
1034 ret
= reserve_bootmem(phys
, len
, flags
);
1040 reserve_bootmem(phys
, len
, BOOTMEM_DEFAULT
);
1043 if (phys
+len
<= MAX_DMA_PFN
*PAGE_SIZE
) {
1044 dma_reserve
+= len
/ PAGE_SIZE
;
1045 set_dma_reserve(dma_reserve
);
1051 int kern_addr_valid(unsigned long addr
)
1053 unsigned long above
= ((long)addr
) >> __VIRTUAL_MASK_SHIFT
;
1059 if (above
!= 0 && above
!= -1UL)
1062 pgd
= pgd_offset_k(addr
);
1066 pud
= pud_offset(pgd
, addr
);
1070 pmd
= pmd_offset(pud
, addr
);
1074 if (pmd_large(*pmd
))
1075 return pfn_valid(pmd_pfn(*pmd
));
1077 pte
= pte_offset_kernel(pmd
, addr
);
1081 return pfn_valid(pte_pfn(*pte
));
1085 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
1086 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
1087 * not need special handling anymore:
1089 static struct vm_area_struct gate_vma
= {
1090 .vm_start
= VSYSCALL_START
,
1091 .vm_end
= VSYSCALL_START
+ (VSYSCALL_MAPPED_PAGES
* PAGE_SIZE
),
1092 .vm_page_prot
= PAGE_READONLY_EXEC
,
1093 .vm_flags
= VM_READ
| VM_EXEC
1096 struct vm_area_struct
*get_gate_vma(struct task_struct
*tsk
)
1098 #ifdef CONFIG_IA32_EMULATION
1099 if (test_tsk_thread_flag(tsk
, TIF_IA32
))
1105 int in_gate_area(struct task_struct
*task
, unsigned long addr
)
1107 struct vm_area_struct
*vma
= get_gate_vma(task
);
1112 return (addr
>= vma
->vm_start
) && (addr
< vma
->vm_end
);
1116 * Use this when you have no reliable task/vma, typically from interrupt
1117 * context. It is less reliable than using the task's vma and may give
1120 int in_gate_area_no_task(unsigned long addr
)
1122 return (addr
>= VSYSCALL_START
) && (addr
< VSYSCALL_END
);
1125 const char *arch_vma_name(struct vm_area_struct
*vma
)
1127 if (vma
->vm_mm
&& vma
->vm_start
== (long)vma
->vm_mm
->context
.vdso
)
1129 if (vma
== &gate_vma
)
1130 return "[vsyscall]";
1134 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1136 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1138 static long __meminitdata addr_start
, addr_end
;
1139 static void __meminitdata
*p_start
, *p_end
;
1140 static int __meminitdata node_start
;
1143 vmemmap_populate(struct page
*start_page
, unsigned long size
, int node
)
1145 unsigned long addr
= (unsigned long)start_page
;
1146 unsigned long end
= (unsigned long)(start_page
+ size
);
1152 for (; addr
< end
; addr
= next
) {
1155 pgd
= vmemmap_pgd_populate(addr
, node
);
1159 pud
= vmemmap_pud_populate(pgd
, addr
, node
);
1164 next
= (addr
+ PAGE_SIZE
) & PAGE_MASK
;
1165 pmd
= vmemmap_pmd_populate(pud
, addr
, node
);
1170 p
= vmemmap_pte_populate(pmd
, addr
, node
);
1175 addr_end
= addr
+ PAGE_SIZE
;
1176 p_end
= p
+ PAGE_SIZE
;
1178 next
= pmd_addr_end(addr
, end
);
1180 pmd
= pmd_offset(pud
, addr
);
1181 if (pmd_none(*pmd
)) {
1184 p
= vmemmap_alloc_block(PMD_SIZE
, node
);
1188 entry
= pfn_pte(__pa(p
) >> PAGE_SHIFT
,
1190 set_pmd(pmd
, __pmd(pte_val(entry
)));
1192 /* check to see if we have contiguous blocks */
1193 if (p_end
!= p
|| node_start
!= node
) {
1195 printk(KERN_DEBUG
" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1196 addr_start
, addr_end
-1, p_start
, p_end
-1, node_start
);
1202 addr_end
= addr
+ PMD_SIZE
;
1203 p_end
= p
+ PMD_SIZE
;
1205 vmemmap_verify((pte_t
*)pmd
, node
, addr
, next
);
1212 void __meminit
vmemmap_populate_print_last(void)
1215 printk(KERN_DEBUG
" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1216 addr_start
, addr_end
-1, p_start
, p_end
-1, node_start
);