1 /*
2 * linux/arch/x86_64/mm/init.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 2000 Pavel Machek <pavel@ucw.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/memblock.h>
25 #include <linux/proc_fs.h>
26 #include <linux/pci.h>
27 #include <linux/pfn.h>
28 #include <linux/poison.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/module.h>
31 #include <linux/memory.h>
32 #include <linux/memory_hotplug.h>
33 #include <linux/nmi.h>
34 #include <linux/gfp.h>
35
36 #include <asm/processor.h>
37 #include <asm/bios_ebda.h>
38 #include <asm/uaccess.h>
39 #include <asm/pgtable.h>
40 #include <asm/pgalloc.h>
41 #include <asm/dma.h>
42 #include <asm/fixmap.h>
43 #include <asm/e820.h>
44 #include <asm/apic.h>
45 #include <asm/tlb.h>
46 #include <asm/mmu_context.h>
47 #include <asm/proto.h>
48 #include <asm/smp.h>
49 #include <asm/sections.h>
50 #include <asm/kdebug.h>
51 #include <asm/numa.h>
52 #include <asm/cacheflush.h>
53 #include <asm/init.h>
54 #include <asm/uv/uv.h>
55 #include <asm/setup.h>
56
parse_direct_gbpages_off(char * arg)57 static int __init parse_direct_gbpages_off(char *arg)
58 {
59 direct_gbpages = 0;
60 return 0;
61 }
62 early_param("nogbpages", parse_direct_gbpages_off);
63
parse_direct_gbpages_on(char * arg)64 static int __init parse_direct_gbpages_on(char *arg)
65 {
66 direct_gbpages = 1;
67 return 0;
68 }
69 early_param("gbpages", parse_direct_gbpages_on);
70
71 /*
72 * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
73 * physical space so we can cache the place of the first one and move
74 * around without checking the pgd every time.
75 */
76
77 pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
78 EXPORT_SYMBOL_GPL(__supported_pte_mask);
79
80 int force_personality32;
81
82 /*
83 * noexec32=on|off
84 * Control non executable heap for 32bit processes.
85 * To control the stack too use noexec=off
86 *
87 * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
88 * off PROT_READ implies PROT_EXEC
89 */
nonx32_setup(char * str)90 static int __init nonx32_setup(char *str)
91 {
92 if (!strcmp(str, "on"))
93 force_personality32 &= ~READ_IMPLIES_EXEC;
94 else if (!strcmp(str, "off"))
95 force_personality32 |= READ_IMPLIES_EXEC;
96 return 1;
97 }
98 __setup("noexec32=", nonx32_setup);
99
100 /*
101 * When memory was added/removed make sure all the processes MM have
102 * suitable PGD entries in the local PGD level page.
103 */
sync_global_pgds(unsigned long start,unsigned long end)104 void sync_global_pgds(unsigned long start, unsigned long end)
105 {
106 unsigned long address;
107
108 for (address = start; address <= end; address += PGDIR_SIZE) {
109 const pgd_t *pgd_ref = pgd_offset_k(address);
110 struct page *page;
111
112 if (pgd_none(*pgd_ref))
113 continue;
114
115 spin_lock(&pgd_lock);
116 list_for_each_entry(page, &pgd_list, lru) {
117 pgd_t *pgd;
118 spinlock_t *pgt_lock;
119
120 pgd = (pgd_t *)page_address(page) + pgd_index(address);
121 /* the pgt_lock only for Xen */
122 pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
123 spin_lock(pgt_lock);
124
125 if (pgd_none(*pgd))
126 set_pgd(pgd, *pgd_ref);
127 else
128 BUG_ON(pgd_page_vaddr(*pgd)
129 != pgd_page_vaddr(*pgd_ref));
130
131 spin_unlock(pgt_lock);
132 }
133 spin_unlock(&pgd_lock);
134 }
135 }
136
137 /*
138 * NOTE: This function is marked __ref because it calls __init function
139 * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
140 */
spp_getpage(void)141 static __ref void *spp_getpage(void)
142 {
143 void *ptr;
144
145 if (after_bootmem)
146 ptr = (void *) get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
147 else
148 ptr = alloc_bootmem_pages(PAGE_SIZE);
149
150 if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
151 panic("set_pte_phys: cannot allocate page data %s\n",
152 after_bootmem ? "after bootmem" : "");
153 }
154
155 pr_debug("spp_getpage %p\n", ptr);
156
157 return ptr;
158 }
159
fill_pud(pgd_t * pgd,unsigned long vaddr)160 static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
161 {
162 if (pgd_none(*pgd)) {
163 pud_t *pud = (pud_t *)spp_getpage();
164 pgd_populate(&init_mm, pgd, pud);
165 if (pud != pud_offset(pgd, 0))
166 printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
167 pud, pud_offset(pgd, 0));
168 }
169 return pud_offset(pgd, vaddr);
170 }
171
fill_pmd(pud_t * pud,unsigned long vaddr)172 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
173 {
174 if (pud_none(*pud)) {
175 pmd_t *pmd = (pmd_t *) spp_getpage();
176 pud_populate(&init_mm, pud, pmd);
177 if (pmd != pmd_offset(pud, 0))
178 printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
179 pmd, pmd_offset(pud, 0));
180 }
181 return pmd_offset(pud, vaddr);
182 }
183
fill_pte(pmd_t * pmd,unsigned long vaddr)184 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
185 {
186 if (pmd_none(*pmd)) {
187 pte_t *pte = (pte_t *) spp_getpage();
188 pmd_populate_kernel(&init_mm, pmd, pte);
189 if (pte != pte_offset_kernel(pmd, 0))
190 printk(KERN_ERR "PAGETABLE BUG #02!\n");
191 }
192 return pte_offset_kernel(pmd, vaddr);
193 }
194
set_pte_vaddr_pud(pud_t * pud_page,unsigned long vaddr,pte_t new_pte)195 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
196 {
197 pud_t *pud;
198 pmd_t *pmd;
199 pte_t *pte;
200
201 pud = pud_page + pud_index(vaddr);
202 pmd = fill_pmd(pud, vaddr);
203 pte = fill_pte(pmd, vaddr);
204
205 set_pte(pte, new_pte);
206
207 /*
208 * It's enough to flush this one mapping.
209 * (PGE mappings get flushed as well)
210 */
211 __flush_tlb_one(vaddr);
212 }
213
set_pte_vaddr(unsigned long vaddr,pte_t pteval)214 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
215 {
216 pgd_t *pgd;
217 pud_t *pud_page;
218
219 pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
220
221 pgd = pgd_offset_k(vaddr);
222 if (pgd_none(*pgd)) {
223 printk(KERN_ERR
224 "PGD FIXMAP MISSING, it should be setup in head.S!\n");
225 return;
226 }
227 pud_page = (pud_t*)pgd_page_vaddr(*pgd);
228 set_pte_vaddr_pud(pud_page, vaddr, pteval);
229 }
230
populate_extra_pmd(unsigned long vaddr)231 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
232 {
233 pgd_t *pgd;
234 pud_t *pud;
235
236 pgd = pgd_offset_k(vaddr);
237 pud = fill_pud(pgd, vaddr);
238 return fill_pmd(pud, vaddr);
239 }
240
populate_extra_pte(unsigned long vaddr)241 pte_t * __init populate_extra_pte(unsigned long vaddr)
242 {
243 pmd_t *pmd;
244
245 pmd = populate_extra_pmd(vaddr);
246 return fill_pte(pmd, vaddr);
247 }
248
249 /*
250 * Create large page table mappings for a range of physical addresses.
251 */
__init_extra_mapping(unsigned long phys,unsigned long size,pgprot_t prot)252 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
253 pgprot_t prot)
254 {
255 pgd_t *pgd;
256 pud_t *pud;
257 pmd_t *pmd;
258
259 BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
260 for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
261 pgd = pgd_offset_k((unsigned long)__va(phys));
262 if (pgd_none(*pgd)) {
263 pud = (pud_t *) spp_getpage();
264 set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE |
265 _PAGE_USER));
266 }
267 pud = pud_offset(pgd, (unsigned long)__va(phys));
268 if (pud_none(*pud)) {
269 pmd = (pmd_t *) spp_getpage();
270 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
271 _PAGE_USER));
272 }
273 pmd = pmd_offset(pud, phys);
274 BUG_ON(!pmd_none(*pmd));
275 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
276 }
277 }
278
init_extra_mapping_wb(unsigned long phys,unsigned long size)279 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
280 {
281 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE);
282 }
283
init_extra_mapping_uc(unsigned long phys,unsigned long size)284 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
285 {
286 __init_extra_mapping(phys, size, PAGE_KERNEL_LARGE_NOCACHE);
287 }
288
289 /*
290 * The head.S code sets up the kernel high mapping:
291 *
292 * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
293 *
294 * phys_addr holds the negative offset to the kernel, which is added
295 * to the compile time generated pmds. This results in invalid pmds up
296 * to the point where we hit the physaddr 0 mapping.
297 *
298 * We limit the mappings to the region from _text to _brk_end. _brk_end
299 * is rounded up to the 2MB boundary. This catches the invalid pmds as
300 * well, as they are located before _text:
301 */
cleanup_highmap(void)302 void __init cleanup_highmap(void)
303 {
304 unsigned long vaddr = __START_KERNEL_map;
305 unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
306 unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
307 pmd_t *pmd = level2_kernel_pgt;
308
309 for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
310 if (pmd_none(*pmd))
311 continue;
312 if (vaddr < (unsigned long) _text || vaddr > end)
313 set_pmd(pmd, __pmd(0));
314 }
315 }
316
alloc_low_page(unsigned long * phys)317 static __ref void *alloc_low_page(unsigned long *phys)
318 {
319 unsigned long pfn = pgt_buf_end++;
320 void *adr;
321
322 if (after_bootmem) {
323 adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
324 *phys = __pa(adr);
325
326 return adr;
327 }
328
329 if (pfn >= pgt_buf_top)
330 panic("alloc_low_page: ran out of memory");
331
332 adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
333 clear_page(adr);
334 *phys = pfn * PAGE_SIZE;
335 return adr;
336 }
337
map_low_page(void * virt)338 static __ref void *map_low_page(void *virt)
339 {
340 void *adr;
341 unsigned long phys, left;
342
343 if (after_bootmem)
344 return virt;
345
346 phys = __pa(virt);
347 left = phys & (PAGE_SIZE - 1);
348 adr = early_memremap(phys & PAGE_MASK, PAGE_SIZE);
349 adr = (void *)(((unsigned long)adr) | left);
350
351 return adr;
352 }
353
unmap_low_page(void * adr)354 static __ref void unmap_low_page(void *adr)
355 {
356 if (after_bootmem)
357 return;
358
359 early_iounmap((void *)((unsigned long)adr & PAGE_MASK), PAGE_SIZE);
360 }
361
362 static unsigned long __meminit
phys_pte_init(pte_t * pte_page,unsigned long addr,unsigned long end,pgprot_t prot)363 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
364 pgprot_t prot)
365 {
366 unsigned pages = 0;
367 unsigned long last_map_addr = end;
368 int i;
369
370 pte_t *pte = pte_page + pte_index(addr);
371
372 for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
373
374 if (addr >= end) {
375 if (!after_bootmem) {
376 for(; i < PTRS_PER_PTE; i++, pte++)
377 set_pte(pte, __pte(0));
378 }
379 break;
380 }
381
382 /*
383 * We will re-use the existing mapping.
384 * Xen for example has some special requirements, like mapping
385 * pagetable pages as RO. So assume someone who pre-setup
386 * these mappings are more intelligent.
387 */
388 if (pte_val(*pte)) {
389 pages++;
390 continue;
391 }
392
393 if (0)
394 printk(" pte=%p addr=%lx pte=%016lx\n",
395 pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);
396 pages++;
397 set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));
398 last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;
399 }
400
401 update_page_count(PG_LEVEL_4K, pages);
402
403 return last_map_addr;
404 }
405
406 static unsigned long __meminit
phys_pmd_init(pmd_t * pmd_page,unsigned long address,unsigned long end,unsigned long page_size_mask,pgprot_t prot)407 phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
408 unsigned long page_size_mask, pgprot_t prot)
409 {
410 unsigned long pages = 0;
411 unsigned long last_map_addr = end;
412
413 int i = pmd_index(address);
414
415 for (; i < PTRS_PER_PMD; i++, address += PMD_SIZE) {
416 unsigned long pte_phys;
417 pmd_t *pmd = pmd_page + pmd_index(address);
418 pte_t *pte;
419 pgprot_t new_prot = prot;
420
421 if (address >= end) {
422 if (!after_bootmem) {
423 for (; i < PTRS_PER_PMD; i++, pmd++)
424 set_pmd(pmd, __pmd(0));
425 }
426 break;
427 }
428
429 if (pmd_val(*pmd)) {
430 if (!pmd_large(*pmd)) {
431 spin_lock(&init_mm.page_table_lock);
432 pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd));
433 last_map_addr = phys_pte_init(pte, address,
434 end, prot);
435 unmap_low_page(pte);
436 spin_unlock(&init_mm.page_table_lock);
437 continue;
438 }
439 /*
440 * If we are ok with PG_LEVEL_2M mapping, then we will
441 * use the existing mapping,
442 *
443 * Otherwise, we will split the large page mapping but
444 * use the same existing protection bits except for
445 * large page, so that we don't violate Intel's TLB
446 * Application note (317080) which says, while changing
447 * the page sizes, new and old translations should
448 * not differ with respect to page frame and
449 * attributes.
450 */
451 if (page_size_mask & (1 << PG_LEVEL_2M)) {
452 pages++;
453 continue;
454 }
455 new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
456 }
457
458 if (page_size_mask & (1<<PG_LEVEL_2M)) {
459 pages++;
460 spin_lock(&init_mm.page_table_lock);
461 set_pte((pte_t *)pmd,
462 pfn_pte(address >> PAGE_SHIFT,
463 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
464 spin_unlock(&init_mm.page_table_lock);
465 last_map_addr = (address & PMD_MASK) + PMD_SIZE;
466 continue;
467 }
468
469 pte = alloc_low_page(&pte_phys);
470 last_map_addr = phys_pte_init(pte, address, end, new_prot);
471 unmap_low_page(pte);
472
473 spin_lock(&init_mm.page_table_lock);
474 pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
475 spin_unlock(&init_mm.page_table_lock);
476 }
477 update_page_count(PG_LEVEL_2M, pages);
478 return last_map_addr;
479 }
480
481 static unsigned long __meminit
phys_pud_init(pud_t * pud_page,unsigned long addr,unsigned long end,unsigned long page_size_mask)482 phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
483 unsigned long page_size_mask)
484 {
485 unsigned long pages = 0;
486 unsigned long last_map_addr = end;
487 int i = pud_index(addr);
488
489 for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE) {
490 unsigned long pmd_phys;
491 pud_t *pud = pud_page + pud_index(addr);
492 pmd_t *pmd;
493 pgprot_t prot = PAGE_KERNEL;
494
495 if (addr >= end)
496 break;
497
498 if (!after_bootmem &&
499 !e820_any_mapped(addr, addr+PUD_SIZE, 0)) {
500 set_pud(pud, __pud(0));
501 continue;
502 }
503
504 if (pud_val(*pud)) {
505 if (!pud_large(*pud)) {
506 pmd = map_low_page(pmd_offset(pud, 0));
507 last_map_addr = phys_pmd_init(pmd, addr, end,
508 page_size_mask, prot);
509 unmap_low_page(pmd);
510 __flush_tlb_all();
511 continue;
512 }
513 /*
514 * If we are ok with PG_LEVEL_1G mapping, then we will
515 * use the existing mapping.
516 *
517 * Otherwise, we will split the gbpage mapping but use
518 * the same existing protection bits except for large
519 * page, so that we don't violate Intel's TLB
520 * Application note (317080) which says, while changing
521 * the page sizes, new and old translations should
522 * not differ with respect to page frame and
523 * attributes.
524 */
525 if (page_size_mask & (1 << PG_LEVEL_1G)) {
526 pages++;
527 continue;
528 }
529 prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
530 }
531
532 if (page_size_mask & (1<<PG_LEVEL_1G)) {
533 pages++;
534 spin_lock(&init_mm.page_table_lock);
535 set_pte((pte_t *)pud,
536 pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
537 spin_unlock(&init_mm.page_table_lock);
538 last_map_addr = (addr & PUD_MASK) + PUD_SIZE;
539 continue;
540 }
541
542 pmd = alloc_low_page(&pmd_phys);
543 last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
544 prot);
545 unmap_low_page(pmd);
546
547 spin_lock(&init_mm.page_table_lock);
548 pud_populate(&init_mm, pud, __va(pmd_phys));
549 spin_unlock(&init_mm.page_table_lock);
550 }
551 __flush_tlb_all();
552
553 update_page_count(PG_LEVEL_1G, pages);
554
555 return last_map_addr;
556 }
557
558 unsigned long __meminit
kernel_physical_mapping_init(unsigned long start,unsigned long end,unsigned long page_size_mask)559 kernel_physical_mapping_init(unsigned long start,
560 unsigned long end,
561 unsigned long page_size_mask)
562 {
563 bool pgd_changed = false;
564 unsigned long next, last_map_addr = end;
565 unsigned long addr;
566
567 start = (unsigned long)__va(start);
568 end = (unsigned long)__va(end);
569 addr = start;
570
571 for (; start < end; start = next) {
572 pgd_t *pgd = pgd_offset_k(start);
573 unsigned long pud_phys;
574 pud_t *pud;
575
576 next = (start + PGDIR_SIZE) & PGDIR_MASK;
577 if (next > end)
578 next = end;
579
580 if (pgd_val(*pgd)) {
581 pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd));
582 last_map_addr = phys_pud_init(pud, __pa(start),
583 __pa(end), page_size_mask);
584 unmap_low_page(pud);
585 continue;
586 }
587
588 pud = alloc_low_page(&pud_phys);
589 last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
590 page_size_mask);
591 unmap_low_page(pud);
592
593 spin_lock(&init_mm.page_table_lock);
594 pgd_populate(&init_mm, pgd, __va(pud_phys));
595 spin_unlock(&init_mm.page_table_lock);
596 pgd_changed = true;
597 }
598
599 if (pgd_changed)
600 sync_global_pgds(addr, end);
601
602 __flush_tlb_all();
603
604 return last_map_addr;
605 }
606
607 #ifndef CONFIG_NUMA
initmem_init(void)608 void __init initmem_init(void)
609 {
610 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
611 }
612 #endif
613
paging_init(void)614 void __init paging_init(void)
615 {
616 sparse_memory_present_with_active_regions(MAX_NUMNODES);
617 sparse_init();
618
619 /*
620 * clear the default setting with node 0
621 * note: don't use nodes_clear here, that is really clearing when
622 * numa support is not compiled in, and later node_set_state
623 * will not set it back.
624 */
625 node_clear_state(0, N_NORMAL_MEMORY);
626
627 zone_sizes_init();
628 }
629
630 /*
631 * Memory hotplug specific functions
632 */
633 #ifdef CONFIG_MEMORY_HOTPLUG
634 /*
635 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
636 * updating.
637 */
update_end_of_memory_vars(u64 start,u64 size)638 static void update_end_of_memory_vars(u64 start, u64 size)
639 {
640 unsigned long end_pfn = PFN_UP(start + size);
641
642 if (end_pfn > max_pfn) {
643 max_pfn = end_pfn;
644 max_low_pfn = end_pfn;
645 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
646 }
647 }
648
649 /*
650 * Memory is added always to NORMAL zone. This means you will never get
651 * additional DMA/DMA32 memory.
652 */
arch_add_memory(int nid,u64 start,u64 size)653 int arch_add_memory(int nid, u64 start, u64 size)
654 {
655 struct pglist_data *pgdat = NODE_DATA(nid);
656 struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
657 unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
658 unsigned long nr_pages = size >> PAGE_SHIFT;
659 int ret;
660
661 last_mapped_pfn = init_memory_mapping(start, start + size);
662 if (last_mapped_pfn > max_pfn_mapped)
663 max_pfn_mapped = last_mapped_pfn;
664
665 ret = __add_pages(nid, zone, start_pfn, nr_pages);
666 WARN_ON_ONCE(ret);
667
668 /* update max_pfn, max_low_pfn and high_memory */
669 update_end_of_memory_vars(start, size);
670
671 return ret;
672 }
673 EXPORT_SYMBOL_GPL(arch_add_memory);
674
675 #endif /* CONFIG_MEMORY_HOTPLUG */
676
677 static struct kcore_list kcore_vsyscall;
678
mem_init(void)679 void __init mem_init(void)
680 {
681 long codesize, reservedpages, datasize, initsize;
682 unsigned long absent_pages;
683
684 pci_iommu_alloc();
685
686 /* clear_bss() already clear the empty_zero_page */
687
688 reservedpages = 0;
689
690 /* this will put all low memory onto the freelists */
691 #ifdef CONFIG_NUMA
692 totalram_pages = numa_free_all_bootmem();
693 #else
694 totalram_pages = free_all_bootmem();
695 #endif
696
697 absent_pages = absent_pages_in_range(0, max_pfn);
698 reservedpages = max_pfn - totalram_pages - absent_pages;
699 after_bootmem = 1;
700
701 codesize = (unsigned long) &_etext - (unsigned long) &_text;
702 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
703 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
704
705 /* Register memory areas for /proc/kcore */
706 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
707 VSYSCALL_END - VSYSCALL_START, KCORE_OTHER);
708
709 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
710 "%ldk absent, %ldk reserved, %ldk data, %ldk init)\n",
711 nr_free_pages() << (PAGE_SHIFT-10),
712 max_pfn << (PAGE_SHIFT-10),
713 codesize >> 10,
714 absent_pages << (PAGE_SHIFT-10),
715 reservedpages << (PAGE_SHIFT-10),
716 datasize >> 10,
717 initsize >> 10);
718 }
719
720 #ifdef CONFIG_DEBUG_RODATA
721 const int rodata_test_data = 0xC3;
722 EXPORT_SYMBOL_GPL(rodata_test_data);
723
724 int kernel_set_to_readonly;
725
set_kernel_text_rw(void)726 void set_kernel_text_rw(void)
727 {
728 unsigned long start = PFN_ALIGN(_text);
729 unsigned long end = PFN_ALIGN(__stop___ex_table);
730
731 if (!kernel_set_to_readonly)
732 return;
733
734 pr_debug("Set kernel text: %lx - %lx for read write\n",
735 start, end);
736
737 /*
738 * Make the kernel identity mapping for text RW. Kernel text
739 * mapping will always be RO. Refer to the comment in
740 * static_protections() in pageattr.c
741 */
742 set_memory_rw(start, (end - start) >> PAGE_SHIFT);
743 }
744
set_kernel_text_ro(void)745 void set_kernel_text_ro(void)
746 {
747 unsigned long start = PFN_ALIGN(_text);
748 unsigned long end = PFN_ALIGN(__stop___ex_table);
749
750 if (!kernel_set_to_readonly)
751 return;
752
753 pr_debug("Set kernel text: %lx - %lx for read only\n",
754 start, end);
755
756 /*
757 * Set the kernel identity mapping for text RO.
758 */
759 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
760 }
761
mark_rodata_ro(void)762 void mark_rodata_ro(void)
763 {
764 unsigned long start = PFN_ALIGN(_text);
765 unsigned long rodata_start =
766 ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
767 unsigned long end = (unsigned long) &__end_rodata_hpage_align;
768 unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table);
769 unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata);
770 unsigned long data_start = (unsigned long) &_sdata;
771
772 printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
773 (end - start) >> 10);
774 set_memory_ro(start, (end - start) >> PAGE_SHIFT);
775
776 kernel_set_to_readonly = 1;
777
778 /*
779 * The rodata section (but not the kernel text!) should also be
780 * not-executable.
781 */
782 set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
783
784 rodata_test();
785
786 #ifdef CONFIG_CPA_DEBUG
787 printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
788 set_memory_rw(start, (end-start) >> PAGE_SHIFT);
789
790 printk(KERN_INFO "Testing CPA: again\n");
791 set_memory_ro(start, (end-start) >> PAGE_SHIFT);
792 #endif
793
794 free_init_pages("unused kernel memory",
795 (unsigned long) page_address(virt_to_page(text_end)),
796 (unsigned long)
797 page_address(virt_to_page(rodata_start)));
798 free_init_pages("unused kernel memory",
799 (unsigned long) page_address(virt_to_page(rodata_end)),
800 (unsigned long) page_address(virt_to_page(data_start)));
801 }
802
803 #endif
804
kern_addr_valid(unsigned long addr)805 int kern_addr_valid(unsigned long addr)
806 {
807 unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
808 pgd_t *pgd;
809 pud_t *pud;
810 pmd_t *pmd;
811 pte_t *pte;
812
813 if (above != 0 && above != -1UL)
814 return 0;
815
816 pgd = pgd_offset_k(addr);
817 if (pgd_none(*pgd))
818 return 0;
819
820 pud = pud_offset(pgd, addr);
821 if (pud_none(*pud))
822 return 0;
823
824 if (pud_large(*pud))
825 return pfn_valid(pud_pfn(*pud));
826
827 pmd = pmd_offset(pud, addr);
828 if (pmd_none(*pmd))
829 return 0;
830
831 if (pmd_large(*pmd))
832 return pfn_valid(pmd_pfn(*pmd));
833
834 pte = pte_offset_kernel(pmd, addr);
835 if (pte_none(*pte))
836 return 0;
837
838 return pfn_valid(pte_pfn(*pte));
839 }
840
841 /*
842 * A pseudo VMA to allow ptrace access for the vsyscall page. This only
843 * covers the 64bit vsyscall page now. 32bit has a real VMA now and does
844 * not need special handling anymore:
845 */
846 static struct vm_area_struct gate_vma = {
847 .vm_start = VSYSCALL_START,
848 .vm_end = VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
849 .vm_page_prot = PAGE_READONLY_EXEC,
850 .vm_flags = VM_READ | VM_EXEC
851 };
852
get_gate_vma(struct mm_struct * mm)853 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
854 {
855 #ifdef CONFIG_IA32_EMULATION
856 if (!mm || mm->context.ia32_compat)
857 return NULL;
858 #endif
859 return &gate_vma;
860 }
861
in_gate_area(struct mm_struct * mm,unsigned long addr)862 int in_gate_area(struct mm_struct *mm, unsigned long addr)
863 {
864 struct vm_area_struct *vma = get_gate_vma(mm);
865
866 if (!vma)
867 return 0;
868
869 return (addr >= vma->vm_start) && (addr < vma->vm_end);
870 }
871
872 /*
873 * Use this when you have no reliable mm, typically from interrupt
874 * context. It is less reliable than using a task's mm and may give
875 * false positives.
876 */
in_gate_area_no_mm(unsigned long addr)877 int in_gate_area_no_mm(unsigned long addr)
878 {
879 return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
880 }
881
arch_vma_name(struct vm_area_struct * vma)882 const char *arch_vma_name(struct vm_area_struct *vma)
883 {
884 if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
885 return "[vdso]";
886 if (vma == &gate_vma)
887 return "[vsyscall]";
888 return NULL;
889 }
890
891 #ifdef CONFIG_X86_UV
memory_block_size_bytes(void)892 unsigned long memory_block_size_bytes(void)
893 {
894 if (is_uv_system()) {
895 printk(KERN_INFO "UV: memory block size 2GB\n");
896 return 2UL * 1024 * 1024 * 1024;
897 }
898 return MIN_MEMORY_BLOCK_SIZE;
899 }
900 #endif
901
902 #ifdef CONFIG_SPARSEMEM_VMEMMAP
903 /*
904 * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
905 */
906 static long __meminitdata addr_start, addr_end;
907 static void __meminitdata *p_start, *p_end;
908 static int __meminitdata node_start;
909
910 int __meminit
vmemmap_populate(struct page * start_page,unsigned long size,int node)911 vmemmap_populate(struct page *start_page, unsigned long size, int node)
912 {
913 unsigned long addr = (unsigned long)start_page;
914 unsigned long end = (unsigned long)(start_page + size);
915 unsigned long next;
916 pgd_t *pgd;
917 pud_t *pud;
918 pmd_t *pmd;
919
920 for (; addr < end; addr = next) {
921 void *p = NULL;
922
923 pgd = vmemmap_pgd_populate(addr, node);
924 if (!pgd)
925 return -ENOMEM;
926
927 pud = vmemmap_pud_populate(pgd, addr, node);
928 if (!pud)
929 return -ENOMEM;
930
931 if (!cpu_has_pse) {
932 next = (addr + PAGE_SIZE) & PAGE_MASK;
933 pmd = vmemmap_pmd_populate(pud, addr, node);
934
935 if (!pmd)
936 return -ENOMEM;
937
938 p = vmemmap_pte_populate(pmd, addr, node);
939
940 if (!p)
941 return -ENOMEM;
942
943 addr_end = addr + PAGE_SIZE;
944 p_end = p + PAGE_SIZE;
945 } else {
946 next = pmd_addr_end(addr, end);
947
948 pmd = pmd_offset(pud, addr);
949 if (pmd_none(*pmd)) {
950 pte_t entry;
951
952 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
953 if (!p)
954 return -ENOMEM;
955
956 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
957 PAGE_KERNEL_LARGE);
958 set_pmd(pmd, __pmd(pte_val(entry)));
959
960 /* check to see if we have contiguous blocks */
961 if (p_end != p || node_start != node) {
962 if (p_start)
963 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
964 addr_start, addr_end-1, p_start, p_end-1, node_start);
965 addr_start = addr;
966 node_start = node;
967 p_start = p;
968 }
969
970 addr_end = addr + PMD_SIZE;
971 p_end = p + PMD_SIZE;
972 } else
973 vmemmap_verify((pte_t *)pmd, node, addr, next);
974 }
975
976 }
977 sync_global_pgds((unsigned long)start_page, end);
978 return 0;
979 }
980
vmemmap_populate_print_last(void)981 void __meminit vmemmap_populate_print_last(void)
982 {
983 if (p_start) {
984 printk(KERN_DEBUG " [%lx-%lx] PMD -> [%p-%p] on node %d\n",
985 addr_start, addr_end-1, p_start, p_end-1, node_start);
986 p_start = NULL;
987 p_end = NULL;
988 node_start = 0;
989 }
990 }
991 #endif
992