Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / arch / x86 / mm / init_64.c
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/memory.h>
31 #include <linux/memory_hotplug.h>
32 #include <linux/memremap.h>
33 #include <linux/nmi.h>
34 #include <linux/gfp.h>
35 #include <linux/kcore.h>
36
37 #include <asm/processor.h>
38 #include <asm/bios_ebda.h>
39 #include <linux/uaccess.h>
40 #include <asm/pgtable.h>
41 #include <asm/pgalloc.h>
42 #include <asm/dma.h>
43 #include <asm/fixmap.h>
44 #include <asm/e820/api.h>
45 #include <asm/apic.h>
46 #include <asm/tlb.h>
47 #include <asm/mmu_context.h>
48 #include <asm/proto.h>
49 #include <asm/smp.h>
50 #include <asm/sections.h>
51 #include <asm/kdebug.h>
52 #include <asm/numa.h>
53 #include <asm/set_memory.h>
54 #include <asm/init.h>
55 #include <asm/uv/uv.h>
56 #include <asm/setup.h>
57
58 #include "mm_internal.h"
59
60 #include "ident_map.c"
61
62 /*
63  * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
64  * physical space so we can cache the place of the first one and move
65  * around without checking the pgd every time.
66  */
67
68 pteval_t __supported_pte_mask __read_mostly = ~0;
69 EXPORT_SYMBOL_GPL(__supported_pte_mask);
70
71 int force_personality32;
72
73 /*
74  * noexec32=on|off
75  * Control non executable heap for 32bit processes.
76  * To control the stack too use noexec=off
77  *
78  * on   PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
79  * off  PROT_READ implies PROT_EXEC
80  */
81 static int __init nonx32_setup(char *str)
82 {
83         if (!strcmp(str, "on"))
84                 force_personality32 &= ~READ_IMPLIES_EXEC;
85         else if (!strcmp(str, "off"))
86                 force_personality32 |= READ_IMPLIES_EXEC;
87         return 1;
88 }
89 __setup("noexec32=", nonx32_setup);
90
91 /*
92  * When memory was added make sure all the processes MM have
93  * suitable PGD entries in the local PGD level page.
94  */
95 #ifdef CONFIG_X86_5LEVEL
96 void sync_global_pgds(unsigned long start, unsigned long end)
97 {
98         unsigned long addr;
99
100         for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
101                 const pgd_t *pgd_ref = pgd_offset_k(addr);
102                 struct page *page;
103
104                 /* Check for overflow */
105                 if (addr < start)
106                         break;
107
108                 if (pgd_none(*pgd_ref))
109                         continue;
110
111                 spin_lock(&pgd_lock);
112                 list_for_each_entry(page, &pgd_list, lru) {
113                         pgd_t *pgd;
114                         spinlock_t *pgt_lock;
115
116                         pgd = (pgd_t *)page_address(page) + pgd_index(addr);
117                         /* the pgt_lock only for Xen */
118                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
119                         spin_lock(pgt_lock);
120
121                         if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
122                                 BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
123
124                         if (pgd_none(*pgd))
125                                 set_pgd(pgd, *pgd_ref);
126
127                         spin_unlock(pgt_lock);
128                 }
129                 spin_unlock(&pgd_lock);
130         }
131 }
132 #else
133 void sync_global_pgds(unsigned long start, unsigned long end)
134 {
135         unsigned long addr;
136
137         for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
138                 pgd_t *pgd_ref = pgd_offset_k(addr);
139                 const p4d_t *p4d_ref;
140                 struct page *page;
141
142                 /*
143                  * With folded p4d, pgd_none() is always false, we need to
144                  * handle synchonization on p4d level.
145                  */
146                 BUILD_BUG_ON(pgd_none(*pgd_ref));
147                 p4d_ref = p4d_offset(pgd_ref, addr);
148
149                 if (p4d_none(*p4d_ref))
150                         continue;
151
152                 spin_lock(&pgd_lock);
153                 list_for_each_entry(page, &pgd_list, lru) {
154                         pgd_t *pgd;
155                         p4d_t *p4d;
156                         spinlock_t *pgt_lock;
157
158                         pgd = (pgd_t *)page_address(page) + pgd_index(addr);
159                         p4d = p4d_offset(pgd, addr);
160                         /* the pgt_lock only for Xen */
161                         pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
162                         spin_lock(pgt_lock);
163
164                         if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
165                                 BUG_ON(p4d_page_vaddr(*p4d)
166                                        != p4d_page_vaddr(*p4d_ref));
167
168                         if (p4d_none(*p4d))
169                                 set_p4d(p4d, *p4d_ref);
170
171                         spin_unlock(pgt_lock);
172                 }
173                 spin_unlock(&pgd_lock);
174         }
175 }
176 #endif
177
178 /*
179  * NOTE: This function is marked __ref because it calls __init function
180  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
181  */
182 static __ref void *spp_getpage(void)
183 {
184         void *ptr;
185
186         if (after_bootmem)
187                 ptr = (void *) get_zeroed_page(GFP_ATOMIC);
188         else
189                 ptr = alloc_bootmem_pages(PAGE_SIZE);
190
191         if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
192                 panic("set_pte_phys: cannot allocate page data %s\n",
193                         after_bootmem ? "after bootmem" : "");
194         }
195
196         pr_debug("spp_getpage %p\n", ptr);
197
198         return ptr;
199 }
200
201 static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
202 {
203         if (pgd_none(*pgd)) {
204                 p4d_t *p4d = (p4d_t *)spp_getpage();
205                 pgd_populate(&init_mm, pgd, p4d);
206                 if (p4d != p4d_offset(pgd, 0))
207                         printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
208                                p4d, p4d_offset(pgd, 0));
209         }
210         return p4d_offset(pgd, vaddr);
211 }
212
213 static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
214 {
215         if (p4d_none(*p4d)) {
216                 pud_t *pud = (pud_t *)spp_getpage();
217                 p4d_populate(&init_mm, p4d, pud);
218                 if (pud != pud_offset(p4d, 0))
219                         printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
220                                pud, pud_offset(p4d, 0));
221         }
222         return pud_offset(p4d, vaddr);
223 }
224
225 static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
226 {
227         if (pud_none(*pud)) {
228                 pmd_t *pmd = (pmd_t *) spp_getpage();
229                 pud_populate(&init_mm, pud, pmd);
230                 if (pmd != pmd_offset(pud, 0))
231                         printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
232                                pmd, pmd_offset(pud, 0));
233         }
234         return pmd_offset(pud, vaddr);
235 }
236
237 static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
238 {
239         if (pmd_none(*pmd)) {
240                 pte_t *pte = (pte_t *) spp_getpage();
241                 pmd_populate_kernel(&init_mm, pmd, pte);
242                 if (pte != pte_offset_kernel(pmd, 0))
243                         printk(KERN_ERR "PAGETABLE BUG #03!\n");
244         }
245         return pte_offset_kernel(pmd, vaddr);
246 }
247
248 static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
249 {
250         pmd_t *pmd = fill_pmd(pud, vaddr);
251         pte_t *pte = fill_pte(pmd, vaddr);
252
253         set_pte(pte, new_pte);
254
255         /*
256          * It's enough to flush this one mapping.
257          * (PGE mappings get flushed as well)
258          */
259         __flush_tlb_one_kernel(vaddr);
260 }
261
262 void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
263 {
264         p4d_t *p4d = p4d_page + p4d_index(vaddr);
265         pud_t *pud = fill_pud(p4d, vaddr);
266
267         __set_pte_vaddr(pud, vaddr, new_pte);
268 }
269
270 void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
271 {
272         pud_t *pud = pud_page + pud_index(vaddr);
273
274         __set_pte_vaddr(pud, vaddr, new_pte);
275 }
276
277 void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
278 {
279         pgd_t *pgd;
280         p4d_t *p4d_page;
281
282         pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
283
284         pgd = pgd_offset_k(vaddr);
285         if (pgd_none(*pgd)) {
286                 printk(KERN_ERR
287                         "PGD FIXMAP MISSING, it should be setup in head.S!\n");
288                 return;
289         }
290
291         p4d_page = p4d_offset(pgd, 0);
292         set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
293 }
294
295 pmd_t * __init populate_extra_pmd(unsigned long vaddr)
296 {
297         pgd_t *pgd;
298         p4d_t *p4d;
299         pud_t *pud;
300
301         pgd = pgd_offset_k(vaddr);
302         p4d = fill_p4d(pgd, vaddr);
303         pud = fill_pud(p4d, vaddr);
304         return fill_pmd(pud, vaddr);
305 }
306
307 pte_t * __init populate_extra_pte(unsigned long vaddr)
308 {
309         pmd_t *pmd;
310
311         pmd = populate_extra_pmd(vaddr);
312         return fill_pte(pmd, vaddr);
313 }
314
315 /*
316  * Create large page table mappings for a range of physical addresses.
317  */
318 static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
319                                         enum page_cache_mode cache)
320 {
321         pgd_t *pgd;
322         p4d_t *p4d;
323         pud_t *pud;
324         pmd_t *pmd;
325         pgprot_t prot;
326
327         pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
328                 pgprot_val(pgprot_4k_2_large(cachemode2pgprot(cache)));
329         BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
330         for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
331                 pgd = pgd_offset_k((unsigned long)__va(phys));
332                 if (pgd_none(*pgd)) {
333                         p4d = (p4d_t *) spp_getpage();
334                         set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
335                                                 _PAGE_USER));
336                 }
337                 p4d = p4d_offset(pgd, (unsigned long)__va(phys));
338                 if (p4d_none(*p4d)) {
339                         pud = (pud_t *) spp_getpage();
340                         set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
341                                                 _PAGE_USER));
342                 }
343                 pud = pud_offset(p4d, (unsigned long)__va(phys));
344                 if (pud_none(*pud)) {
345                         pmd = (pmd_t *) spp_getpage();
346                         set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
347                                                 _PAGE_USER));
348                 }
349                 pmd = pmd_offset(pud, phys);
350                 BUG_ON(!pmd_none(*pmd));
351                 set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
352         }
353 }
354
355 void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
356 {
357         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
358 }
359
360 void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
361 {
362         __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
363 }
364
365 /*
366  * The head.S code sets up the kernel high mapping:
367  *
368  *   from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
369  *
370  * phys_base holds the negative offset to the kernel, which is added
371  * to the compile time generated pmds. This results in invalid pmds up
372  * to the point where we hit the physaddr 0 mapping.
373  *
374  * We limit the mappings to the region from _text to _brk_end.  _brk_end
375  * is rounded up to the 2MB boundary. This catches the invalid pmds as
376  * well, as they are located before _text:
377  */
378 void __init cleanup_highmap(void)
379 {
380         unsigned long vaddr = __START_KERNEL_map;
381         unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
382         unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
383         pmd_t *pmd = level2_kernel_pgt;
384
385         /*
386          * Native path, max_pfn_mapped is not set yet.
387          * Xen has valid max_pfn_mapped set in
388          *      arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
389          */
390         if (max_pfn_mapped)
391                 vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
392
393         for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
394                 if (pmd_none(*pmd))
395                         continue;
396                 if (vaddr < (unsigned long) _text || vaddr > end)
397                         set_pmd(pmd, __pmd(0));
398         }
399 }
400
401 /*
402  * Create PTE level page table mapping for physical addresses.
403  * It returns the last physical address mapped.
404  */
405 static unsigned long __meminit
406 phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
407               pgprot_t prot)
408 {
409         unsigned long pages = 0, paddr_next;
410         unsigned long paddr_last = paddr_end;
411         pte_t *pte;
412         int i;
413
414         pte = pte_page + pte_index(paddr);
415         i = pte_index(paddr);
416
417         for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
418                 paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
419                 if (paddr >= paddr_end) {
420                         if (!after_bootmem &&
421                             !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
422                                              E820_TYPE_RAM) &&
423                             !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
424                                              E820_TYPE_RESERVED_KERN))
425                                 set_pte(pte, __pte(0));
426                         continue;
427                 }
428
429                 /*
430                  * We will re-use the existing mapping.
431                  * Xen for example has some special requirements, like mapping
432                  * pagetable pages as RO. So assume someone who pre-setup
433                  * these mappings are more intelligent.
434                  */
435                 if (!pte_none(*pte)) {
436                         if (!after_bootmem)
437                                 pages++;
438                         continue;
439                 }
440
441                 if (0)
442                         pr_info("   pte=%p addr=%lx pte=%016lx\n", pte, paddr,
443                                 pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
444                 pages++;
445                 set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));
446                 paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
447         }
448
449         update_page_count(PG_LEVEL_4K, pages);
450
451         return paddr_last;
452 }
453
454 /*
455  * Create PMD level page table mapping for physical addresses. The virtual
456  * and physical address have to be aligned at this level.
457  * It returns the last physical address mapped.
458  */
459 static unsigned long __meminit
460 phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
461               unsigned long page_size_mask, pgprot_t prot)
462 {
463         unsigned long pages = 0, paddr_next;
464         unsigned long paddr_last = paddr_end;
465
466         int i = pmd_index(paddr);
467
468         for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
469                 pmd_t *pmd = pmd_page + pmd_index(paddr);
470                 pte_t *pte;
471                 pgprot_t new_prot = prot;
472
473                 paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
474                 if (paddr >= paddr_end) {
475                         if (!after_bootmem &&
476                             !e820__mapped_any(paddr & PMD_MASK, paddr_next,
477                                              E820_TYPE_RAM) &&
478                             !e820__mapped_any(paddr & PMD_MASK, paddr_next,
479                                              E820_TYPE_RESERVED_KERN))
480                                 set_pmd(pmd, __pmd(0));
481                         continue;
482                 }
483
484                 if (!pmd_none(*pmd)) {
485                         if (!pmd_large(*pmd)) {
486                                 spin_lock(&init_mm.page_table_lock);
487                                 pte = (pte_t *)pmd_page_vaddr(*pmd);
488                                 paddr_last = phys_pte_init(pte, paddr,
489                                                            paddr_end, prot);
490                                 spin_unlock(&init_mm.page_table_lock);
491                                 continue;
492                         }
493                         /*
494                          * If we are ok with PG_LEVEL_2M mapping, then we will
495                          * use the existing mapping,
496                          *
497                          * Otherwise, we will split the large page mapping but
498                          * use the same existing protection bits except for
499                          * large page, so that we don't violate Intel's TLB
500                          * Application note (317080) which says, while changing
501                          * the page sizes, new and old translations should
502                          * not differ with respect to page frame and
503                          * attributes.
504                          */
505                         if (page_size_mask & (1 << PG_LEVEL_2M)) {
506                                 if (!after_bootmem)
507                                         pages++;
508                                 paddr_last = paddr_next;
509                                 continue;
510                         }
511                         new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
512                 }
513
514                 if (page_size_mask & (1<<PG_LEVEL_2M)) {
515                         pages++;
516                         spin_lock(&init_mm.page_table_lock);
517                         set_pte((pte_t *)pmd,
518                                 pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,
519                                         __pgprot(pgprot_val(prot) | _PAGE_PSE)));
520                         spin_unlock(&init_mm.page_table_lock);
521                         paddr_last = paddr_next;
522                         continue;
523                 }
524
525                 pte = alloc_low_page();
526                 paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot);
527
528                 spin_lock(&init_mm.page_table_lock);
529                 pmd_populate_kernel(&init_mm, pmd, pte);
530                 spin_unlock(&init_mm.page_table_lock);
531         }
532         update_page_count(PG_LEVEL_2M, pages);
533         return paddr_last;
534 }
535
536 /*
537  * Create PUD level page table mapping for physical addresses. The virtual
538  * and physical address do not have to be aligned at this level. KASLR can
539  * randomize virtual addresses up to this level.
540  * It returns the last physical address mapped.
541  */
542 static unsigned long __meminit
543 phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
544               unsigned long page_size_mask)
545 {
546         unsigned long pages = 0, paddr_next;
547         unsigned long paddr_last = paddr_end;
548         unsigned long vaddr = (unsigned long)__va(paddr);
549         int i = pud_index(vaddr);
550
551         for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
552                 pud_t *pud;
553                 pmd_t *pmd;
554                 pgprot_t prot = PAGE_KERNEL;
555
556                 vaddr = (unsigned long)__va(paddr);
557                 pud = pud_page + pud_index(vaddr);
558                 paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
559
560                 if (paddr >= paddr_end) {
561                         if (!after_bootmem &&
562                             !e820__mapped_any(paddr & PUD_MASK, paddr_next,
563                                              E820_TYPE_RAM) &&
564                             !e820__mapped_any(paddr & PUD_MASK, paddr_next,
565                                              E820_TYPE_RESERVED_KERN))
566                                 set_pud(pud, __pud(0));
567                         continue;
568                 }
569
570                 if (!pud_none(*pud)) {
571                         if (!pud_large(*pud)) {
572                                 pmd = pmd_offset(pud, 0);
573                                 paddr_last = phys_pmd_init(pmd, paddr,
574                                                            paddr_end,
575                                                            page_size_mask,
576                                                            prot);
577                                 __flush_tlb_all();
578                                 continue;
579                         }
580                         /*
581                          * If we are ok with PG_LEVEL_1G mapping, then we will
582                          * use the existing mapping.
583                          *
584                          * Otherwise, we will split the gbpage mapping but use
585                          * the same existing protection  bits except for large
586                          * page, so that we don't violate Intel's TLB
587                          * Application note (317080) which says, while changing
588                          * the page sizes, new and old translations should
589                          * not differ with respect to page frame and
590                          * attributes.
591                          */
592                         if (page_size_mask & (1 << PG_LEVEL_1G)) {
593                                 if (!after_bootmem)
594                                         pages++;
595                                 paddr_last = paddr_next;
596                                 continue;
597                         }
598                         prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
599                 }
600
601                 if (page_size_mask & (1<<PG_LEVEL_1G)) {
602                         pages++;
603                         spin_lock(&init_mm.page_table_lock);
604                         set_pte((pte_t *)pud,
605                                 pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,
606                                         PAGE_KERNEL_LARGE));
607                         spin_unlock(&init_mm.page_table_lock);
608                         paddr_last = paddr_next;
609                         continue;
610                 }
611
612                 pmd = alloc_low_page();
613                 paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
614                                            page_size_mask, prot);
615
616                 spin_lock(&init_mm.page_table_lock);
617                 pud_populate(&init_mm, pud, pmd);
618                 spin_unlock(&init_mm.page_table_lock);
619         }
620         __flush_tlb_all();
621
622         update_page_count(PG_LEVEL_1G, pages);
623
624         return paddr_last;
625 }
626
627 static unsigned long __meminit
628 phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
629               unsigned long page_size_mask)
630 {
631         unsigned long paddr_next, paddr_last = paddr_end;
632         unsigned long vaddr = (unsigned long)__va(paddr);
633         int i = p4d_index(vaddr);
634
635         if (!IS_ENABLED(CONFIG_X86_5LEVEL))
636                 return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end, page_size_mask);
637
638         for (; i < PTRS_PER_P4D; i++, paddr = paddr_next) {
639                 p4d_t *p4d;
640                 pud_t *pud;
641
642                 vaddr = (unsigned long)__va(paddr);
643                 p4d = p4d_page + p4d_index(vaddr);
644                 paddr_next = (paddr & P4D_MASK) + P4D_SIZE;
645
646                 if (paddr >= paddr_end) {
647                         if (!after_bootmem &&
648                             !e820__mapped_any(paddr & P4D_MASK, paddr_next,
649                                              E820_TYPE_RAM) &&
650                             !e820__mapped_any(paddr & P4D_MASK, paddr_next,
651                                              E820_TYPE_RESERVED_KERN))
652                                 set_p4d(p4d, __p4d(0));
653                         continue;
654                 }
655
656                 if (!p4d_none(*p4d)) {
657                         pud = pud_offset(p4d, 0);
658                         paddr_last = phys_pud_init(pud, paddr,
659                                         paddr_end,
660                                         page_size_mask);
661                         __flush_tlb_all();
662                         continue;
663                 }
664
665                 pud = alloc_low_page();
666                 paddr_last = phys_pud_init(pud, paddr, paddr_end,
667                                            page_size_mask);
668
669                 spin_lock(&init_mm.page_table_lock);
670                 p4d_populate(&init_mm, p4d, pud);
671                 spin_unlock(&init_mm.page_table_lock);
672         }
673         __flush_tlb_all();
674
675         return paddr_last;
676 }
677
678 /*
679  * Create page table mapping for the physical memory for specific physical
680  * addresses. The virtual and physical addresses have to be aligned on PMD level
681  * down. It returns the last physical address mapped.
682  */
683 unsigned long __meminit
684 kernel_physical_mapping_init(unsigned long paddr_start,
685                              unsigned long paddr_end,
686                              unsigned long page_size_mask)
687 {
688         bool pgd_changed = false;
689         unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
690
691         paddr_last = paddr_end;
692         vaddr = (unsigned long)__va(paddr_start);
693         vaddr_end = (unsigned long)__va(paddr_end);
694         vaddr_start = vaddr;
695
696         for (; vaddr < vaddr_end; vaddr = vaddr_next) {
697                 pgd_t *pgd = pgd_offset_k(vaddr);
698                 p4d_t *p4d;
699
700                 vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
701
702                 if (pgd_val(*pgd)) {
703                         p4d = (p4d_t *)pgd_page_vaddr(*pgd);
704                         paddr_last = phys_p4d_init(p4d, __pa(vaddr),
705                                                    __pa(vaddr_end),
706                                                    page_size_mask);
707                         continue;
708                 }
709
710                 p4d = alloc_low_page();
711                 paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
712                                            page_size_mask);
713
714                 spin_lock(&init_mm.page_table_lock);
715                 if (IS_ENABLED(CONFIG_X86_5LEVEL))
716                         pgd_populate(&init_mm, pgd, p4d);
717                 else
718                         p4d_populate(&init_mm, p4d_offset(pgd, vaddr), (pud_t *) p4d);
719                 spin_unlock(&init_mm.page_table_lock);
720                 pgd_changed = true;
721         }
722
723         if (pgd_changed)
724                 sync_global_pgds(vaddr_start, vaddr_end - 1);
725
726         __flush_tlb_all();
727
728         return paddr_last;
729 }
730
731 #ifndef CONFIG_NUMA
732 void __init initmem_init(void)
733 {
734         memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
735 }
736 #endif
737
738 void __init paging_init(void)
739 {
740         sparse_memory_present_with_active_regions(MAX_NUMNODES);
741         sparse_init();
742
743         /*
744          * clear the default setting with node 0
745          * note: don't use nodes_clear here, that is really clearing when
746          *       numa support is not compiled in, and later node_set_state
747          *       will not set it back.
748          */
749         node_clear_state(0, N_MEMORY);
750         if (N_MEMORY != N_NORMAL_MEMORY)
751                 node_clear_state(0, N_NORMAL_MEMORY);
752
753         zone_sizes_init();
754 }
755
756 /*
757  * Memory hotplug specific functions
758  */
759 #ifdef CONFIG_MEMORY_HOTPLUG
760 /*
761  * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
762  * updating.
763  */
764 static void update_end_of_memory_vars(u64 start, u64 size)
765 {
766         unsigned long end_pfn = PFN_UP(start + size);
767
768         if (end_pfn > max_pfn) {
769                 max_pfn = end_pfn;
770                 max_low_pfn = end_pfn;
771                 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
772         }
773 }
774
775 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
776                 struct vmem_altmap *altmap, bool want_memblock)
777 {
778         int ret;
779
780         ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
781         WARN_ON_ONCE(ret);
782
783         /* update max_pfn, max_low_pfn and high_memory */
784         update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
785                                   nr_pages << PAGE_SHIFT);
786
787         return ret;
788 }
789
790 int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
791                 bool want_memblock)
792 {
793         unsigned long start_pfn = start >> PAGE_SHIFT;
794         unsigned long nr_pages = size >> PAGE_SHIFT;
795
796         init_memory_mapping(start, start + size);
797
798         return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
799 }
800
801 #define PAGE_INUSE 0xFD
802
803 static void __meminit free_pagetable(struct page *page, int order,
804                 struct vmem_altmap *altmap)
805 {
806         unsigned long magic;
807         unsigned int nr_pages = 1 << order;
808
809         if (altmap) {
810                 vmem_altmap_free(altmap, nr_pages);
811                 return;
812         }
813
814         /* bootmem page has reserved flag */
815         if (PageReserved(page)) {
816                 __ClearPageReserved(page);
817
818                 magic = (unsigned long)page->freelist;
819                 if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
820                         while (nr_pages--)
821                                 put_page_bootmem(page++);
822                 } else
823                         while (nr_pages--)
824                                 free_reserved_page(page++);
825         } else
826                 free_pages((unsigned long)page_address(page), order);
827 }
828
829 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd,
830                 struct vmem_altmap *altmap)
831 {
832         pte_t *pte;
833         int i;
834
835         for (i = 0; i < PTRS_PER_PTE; i++) {
836                 pte = pte_start + i;
837                 if (!pte_none(*pte))
838                         return;
839         }
840
841         /* free a pte talbe */
842         free_pagetable(pmd_page(*pmd), 0, altmap);
843         spin_lock(&init_mm.page_table_lock);
844         pmd_clear(pmd);
845         spin_unlock(&init_mm.page_table_lock);
846 }
847
848 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud,
849                 struct vmem_altmap *altmap)
850 {
851         pmd_t *pmd;
852         int i;
853
854         for (i = 0; i < PTRS_PER_PMD; i++) {
855                 pmd = pmd_start + i;
856                 if (!pmd_none(*pmd))
857                         return;
858         }
859
860         /* free a pmd talbe */
861         free_pagetable(pud_page(*pud), 0, altmap);
862         spin_lock(&init_mm.page_table_lock);
863         pud_clear(pud);
864         spin_unlock(&init_mm.page_table_lock);
865 }
866
867 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d,
868                 struct vmem_altmap *altmap)
869 {
870         pud_t *pud;
871         int i;
872
873         for (i = 0; i < PTRS_PER_PUD; i++) {
874                 pud = pud_start + i;
875                 if (!pud_none(*pud))
876                         return;
877         }
878
879         /* free a pud talbe */
880         free_pagetable(p4d_page(*p4d), 0, altmap);
881         spin_lock(&init_mm.page_table_lock);
882         p4d_clear(p4d);
883         spin_unlock(&init_mm.page_table_lock);
884 }
885
886 static void __meminit
887 remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
888                  struct vmem_altmap *altmap, bool direct)
889 {
890         unsigned long next, pages = 0;
891         pte_t *pte;
892         void *page_addr;
893         phys_addr_t phys_addr;
894
895         pte = pte_start + pte_index(addr);
896         for (; addr < end; addr = next, pte++) {
897                 next = (addr + PAGE_SIZE) & PAGE_MASK;
898                 if (next > end)
899                         next = end;
900
901                 if (!pte_present(*pte))
902                         continue;
903
904                 /*
905                  * We mapped [0,1G) memory as identity mapping when
906                  * initializing, in arch/x86/kernel/head_64.S. These
907                  * pagetables cannot be removed.
908                  */
909                 phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
910                 if (phys_addr < (phys_addr_t)0x40000000)
911                         return;
912
913                 if (PAGE_ALIGNED(addr) && PAGE_ALIGNED(next)) {
914                         /*
915                          * Do not free direct mapping pages since they were
916                          * freed when offlining, or simplely not in use.
917                          */
918                         if (!direct)
919                                 free_pagetable(pte_page(*pte), 0, altmap);
920
921                         spin_lock(&init_mm.page_table_lock);
922                         pte_clear(&init_mm, addr, pte);
923                         spin_unlock(&init_mm.page_table_lock);
924
925                         /* For non-direct mapping, pages means nothing. */
926                         pages++;
927                 } else {
928                         /*
929                          * If we are here, we are freeing vmemmap pages since
930                          * direct mapped memory ranges to be freed are aligned.
931                          *
932                          * If we are not removing the whole page, it means
933                          * other page structs in this page are being used and
934                          * we canot remove them. So fill the unused page_structs
935                          * with 0xFD, and remove the page when it is wholly
936                          * filled with 0xFD.
937                          */
938                         memset((void *)addr, PAGE_INUSE, next - addr);
939
940                         page_addr = page_address(pte_page(*pte));
941                         if (!memchr_inv(page_addr, PAGE_INUSE, PAGE_SIZE)) {
942                                 free_pagetable(pte_page(*pte), 0, altmap);
943
944                                 spin_lock(&init_mm.page_table_lock);
945                                 pte_clear(&init_mm, addr, pte);
946                                 spin_unlock(&init_mm.page_table_lock);
947                         }
948                 }
949         }
950
951         /* Call free_pte_table() in remove_pmd_table(). */
952         flush_tlb_all();
953         if (direct)
954                 update_page_count(PG_LEVEL_4K, -pages);
955 }
956
957 static void __meminit
958 remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
959                  bool direct, struct vmem_altmap *altmap)
960 {
961         unsigned long next, pages = 0;
962         pte_t *pte_base;
963         pmd_t *pmd;
964         void *page_addr;
965
966         pmd = pmd_start + pmd_index(addr);
967         for (; addr < end; addr = next, pmd++) {
968                 next = pmd_addr_end(addr, end);
969
970                 if (!pmd_present(*pmd))
971                         continue;
972
973                 if (pmd_large(*pmd)) {
974                         if (IS_ALIGNED(addr, PMD_SIZE) &&
975                             IS_ALIGNED(next, PMD_SIZE)) {
976                                 if (!direct)
977                                         free_pagetable(pmd_page(*pmd),
978                                                        get_order(PMD_SIZE),
979                                                        altmap);
980
981                                 spin_lock(&init_mm.page_table_lock);
982                                 pmd_clear(pmd);
983                                 spin_unlock(&init_mm.page_table_lock);
984                                 pages++;
985                         } else {
986                                 /* If here, we are freeing vmemmap pages. */
987                                 memset((void *)addr, PAGE_INUSE, next - addr);
988
989                                 page_addr = page_address(pmd_page(*pmd));
990                                 if (!memchr_inv(page_addr, PAGE_INUSE,
991                                                 PMD_SIZE)) {
992                                         free_pagetable(pmd_page(*pmd),
993                                                        get_order(PMD_SIZE),
994                                                        altmap);
995
996                                         spin_lock(&init_mm.page_table_lock);
997                                         pmd_clear(pmd);
998                                         spin_unlock(&init_mm.page_table_lock);
999                                 }
1000                         }
1001
1002                         continue;
1003                 }
1004
1005                 pte_base = (pte_t *)pmd_page_vaddr(*pmd);
1006                 remove_pte_table(pte_base, addr, next, altmap, direct);
1007                 free_pte_table(pte_base, pmd, altmap);
1008         }
1009
1010         /* Call free_pmd_table() in remove_pud_table(). */
1011         if (direct)
1012                 update_page_count(PG_LEVEL_2M, -pages);
1013 }
1014
1015 static void __meminit
1016 remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
1017                  struct vmem_altmap *altmap, bool direct)
1018 {
1019         unsigned long next, pages = 0;
1020         pmd_t *pmd_base;
1021         pud_t *pud;
1022         void *page_addr;
1023
1024         pud = pud_start + pud_index(addr);
1025         for (; addr < end; addr = next, pud++) {
1026                 next = pud_addr_end(addr, end);
1027
1028                 if (!pud_present(*pud))
1029                         continue;
1030
1031                 if (pud_large(*pud)) {
1032                         if (IS_ALIGNED(addr, PUD_SIZE) &&
1033                             IS_ALIGNED(next, PUD_SIZE)) {
1034                                 if (!direct)
1035                                         free_pagetable(pud_page(*pud),
1036                                                        get_order(PUD_SIZE),
1037                                                        altmap);
1038
1039                                 spin_lock(&init_mm.page_table_lock);
1040                                 pud_clear(pud);
1041                                 spin_unlock(&init_mm.page_table_lock);
1042                                 pages++;
1043                         } else {
1044                                 /* If here, we are freeing vmemmap pages. */
1045                                 memset((void *)addr, PAGE_INUSE, next - addr);
1046
1047                                 page_addr = page_address(pud_page(*pud));
1048                                 if (!memchr_inv(page_addr, PAGE_INUSE,
1049                                                 PUD_SIZE)) {
1050                                         free_pagetable(pud_page(*pud),
1051                                                        get_order(PUD_SIZE),
1052                                                        altmap);
1053
1054                                         spin_lock(&init_mm.page_table_lock);
1055                                         pud_clear(pud);
1056                                         spin_unlock(&init_mm.page_table_lock);
1057                                 }
1058                         }
1059
1060                         continue;
1061                 }
1062
1063                 pmd_base = pmd_offset(pud, 0);
1064                 remove_pmd_table(pmd_base, addr, next, direct, altmap);
1065                 free_pmd_table(pmd_base, pud, altmap);
1066         }
1067
1068         if (direct)
1069                 update_page_count(PG_LEVEL_1G, -pages);
1070 }
1071
1072 static void __meminit
1073 remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
1074                  struct vmem_altmap *altmap, bool direct)
1075 {
1076         unsigned long next, pages = 0;
1077         pud_t *pud_base;
1078         p4d_t *p4d;
1079
1080         p4d = p4d_start + p4d_index(addr);
1081         for (; addr < end; addr = next, p4d++) {
1082                 next = p4d_addr_end(addr, end);
1083
1084                 if (!p4d_present(*p4d))
1085                         continue;
1086
1087                 BUILD_BUG_ON(p4d_large(*p4d));
1088
1089                 pud_base = pud_offset(p4d, 0);
1090                 remove_pud_table(pud_base, addr, next, altmap, direct);
1091                 /*
1092                  * For 4-level page tables we do not want to free PUDs, but in the
1093                  * 5-level case we should free them. This code will have to change
1094                  * to adapt for boot-time switching between 4 and 5 level page tables.
1095                  */
1096                 if (CONFIG_PGTABLE_LEVELS == 5)
1097                         free_pud_table(pud_base, p4d, altmap);
1098         }
1099
1100         if (direct)
1101                 update_page_count(PG_LEVEL_512G, -pages);
1102 }
1103
1104 /* start and end are both virtual address. */
1105 static void __meminit
1106 remove_pagetable(unsigned long start, unsigned long end, bool direct,
1107                 struct vmem_altmap *altmap)
1108 {
1109         unsigned long next;
1110         unsigned long addr;
1111         pgd_t *pgd;
1112         p4d_t *p4d;
1113
1114         for (addr = start; addr < end; addr = next) {
1115                 next = pgd_addr_end(addr, end);
1116
1117                 pgd = pgd_offset_k(addr);
1118                 if (!pgd_present(*pgd))
1119                         continue;
1120
1121                 p4d = p4d_offset(pgd, 0);
1122                 remove_p4d_table(p4d, addr, next, altmap, direct);
1123         }
1124
1125         flush_tlb_all();
1126 }
1127
1128 void __ref vmemmap_free(unsigned long start, unsigned long end,
1129                 struct vmem_altmap *altmap)
1130 {
1131         remove_pagetable(start, end, false, altmap);
1132 }
1133
1134 #ifdef CONFIG_MEMORY_HOTREMOVE
1135 static void __meminit
1136 kernel_physical_mapping_remove(unsigned long start, unsigned long end)
1137 {
1138         start = (unsigned long)__va(start);
1139         end = (unsigned long)__va(end);
1140
1141         remove_pagetable(start, end, true, NULL);
1142 }
1143
1144 int __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
1145 {
1146         unsigned long start_pfn = start >> PAGE_SHIFT;
1147         unsigned long nr_pages = size >> PAGE_SHIFT;
1148         struct page *page = pfn_to_page(start_pfn);
1149         struct zone *zone;
1150         int ret;
1151
1152         /* With altmap the first mapped page is offset from @start */
1153         if (altmap)
1154                 page += vmem_altmap_offset(altmap);
1155         zone = page_zone(page);
1156         ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
1157         WARN_ON_ONCE(ret);
1158         kernel_physical_mapping_remove(start, start + size);
1159
1160         return ret;
1161 }
1162 #endif
1163 #endif /* CONFIG_MEMORY_HOTPLUG */
1164
1165 static struct kcore_list kcore_vsyscall;
1166
1167 static void __init register_page_bootmem_info(void)
1168 {
1169 #ifdef CONFIG_NUMA
1170         int i;
1171
1172         for_each_online_node(i)
1173                 register_page_bootmem_info_node(NODE_DATA(i));
1174 #endif
1175 }
1176
1177 void __init mem_init(void)
1178 {
1179         pci_iommu_alloc();
1180
1181         /* clear_bss() already clear the empty_zero_page */
1182
1183         /* this will put all memory onto the freelists */
1184         free_all_bootmem();
1185         after_bootmem = 1;
1186
1187         /*
1188          * Must be done after boot memory is put on freelist, because here we
1189          * might set fields in deferred struct pages that have not yet been
1190          * initialized, and free_all_bootmem() initializes all the reserved
1191          * deferred pages for us.
1192          */
1193         register_page_bootmem_info();
1194
1195         /* Register memory areas for /proc/kcore */
1196         if (get_gate_vma(&init_mm))
1197                 kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
1198
1199         mem_init_print_info(NULL);
1200 }
1201
1202 int kernel_set_to_readonly;
1203
1204 void set_kernel_text_rw(void)
1205 {
1206         unsigned long start = PFN_ALIGN(_text);
1207         unsigned long end = PFN_ALIGN(__stop___ex_table);
1208
1209         if (!kernel_set_to_readonly)
1210                 return;
1211
1212         pr_debug("Set kernel text: %lx - %lx for read write\n",
1213                  start, end);
1214
1215         /*
1216          * Make the kernel identity mapping for text RW. Kernel text
1217          * mapping will always be RO. Refer to the comment in
1218          * static_protections() in pageattr.c
1219          */
1220         set_memory_rw(start, (end - start) >> PAGE_SHIFT);
1221 }
1222
1223 void set_kernel_text_ro(void)
1224 {
1225         unsigned long start = PFN_ALIGN(_text);
1226         unsigned long end = PFN_ALIGN(__stop___ex_table);
1227
1228         if (!kernel_set_to_readonly)
1229                 return;
1230
1231         pr_debug("Set kernel text: %lx - %lx for read only\n",
1232                  start, end);
1233
1234         /*
1235          * Set the kernel identity mapping for text RO.
1236          */
1237         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1238 }
1239
1240 void mark_rodata_ro(void)
1241 {
1242         unsigned long start = PFN_ALIGN(_text);
1243         unsigned long rodata_start = PFN_ALIGN(__start_rodata);
1244         unsigned long end = (unsigned long) &__end_rodata_hpage_align;
1245         unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
1246         unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
1247         unsigned long all_end;
1248
1249         printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
1250                (end - start) >> 10);
1251         set_memory_ro(start, (end - start) >> PAGE_SHIFT);
1252
1253         kernel_set_to_readonly = 1;
1254
1255         /*
1256          * The rodata/data/bss/brk section (but not the kernel text!)
1257          * should also be not-executable.
1258          *
1259          * We align all_end to PMD_SIZE because the existing mapping
1260          * is a full PMD. If we would align _brk_end to PAGE_SIZE we
1261          * split the PMD and the reminder between _brk_end and the end
1262          * of the PMD will remain mapped executable.
1263          *
1264          * Any PMD which was setup after the one which covers _brk_end
1265          * has been zapped already via cleanup_highmem().
1266          */
1267         all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
1268         set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
1269
1270 #ifdef CONFIG_CPA_DEBUG
1271         printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
1272         set_memory_rw(start, (end-start) >> PAGE_SHIFT);
1273
1274         printk(KERN_INFO "Testing CPA: again\n");
1275         set_memory_ro(start, (end-start) >> PAGE_SHIFT);
1276 #endif
1277
1278         free_init_pages("unused kernel",
1279                         (unsigned long) __va(__pa_symbol(text_end)),
1280                         (unsigned long) __va(__pa_symbol(rodata_start)));
1281         free_init_pages("unused kernel",
1282                         (unsigned long) __va(__pa_symbol(rodata_end)),
1283                         (unsigned long) __va(__pa_symbol(_sdata)));
1284
1285         debug_checkwx();
1286 }
1287
1288 int kern_addr_valid(unsigned long addr)
1289 {
1290         unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
1291         pgd_t *pgd;
1292         p4d_t *p4d;
1293         pud_t *pud;
1294         pmd_t *pmd;
1295         pte_t *pte;
1296
1297         if (above != 0 && above != -1UL)
1298                 return 0;
1299
1300         pgd = pgd_offset_k(addr);
1301         if (pgd_none(*pgd))
1302                 return 0;
1303
1304         p4d = p4d_offset(pgd, addr);
1305         if (p4d_none(*p4d))
1306                 return 0;
1307
1308         pud = pud_offset(p4d, addr);
1309         if (pud_none(*pud))
1310                 return 0;
1311
1312         if (pud_large(*pud))
1313                 return pfn_valid(pud_pfn(*pud));
1314
1315         pmd = pmd_offset(pud, addr);
1316         if (pmd_none(*pmd))
1317                 return 0;
1318
1319         if (pmd_large(*pmd))
1320                 return pfn_valid(pmd_pfn(*pmd));
1321
1322         pte = pte_offset_kernel(pmd, addr);
1323         if (pte_none(*pte))
1324                 return 0;
1325
1326         return pfn_valid(pte_pfn(*pte));
1327 }
1328
1329 static unsigned long probe_memory_block_size(void)
1330 {
1331         unsigned long bz = MIN_MEMORY_BLOCK_SIZE;
1332
1333         /* if system is UV or has 64GB of RAM or more, use large blocks */
1334         if (is_uv_system() || ((max_pfn << PAGE_SHIFT) >= (64UL << 30)))
1335                 bz = 2UL << 30; /* 2GB */
1336
1337         pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
1338
1339         return bz;
1340 }
1341
1342 static unsigned long memory_block_size_probed;
1343 unsigned long memory_block_size_bytes(void)
1344 {
1345         if (!memory_block_size_probed)
1346                 memory_block_size_probed = probe_memory_block_size();
1347
1348         return memory_block_size_probed;
1349 }
1350
1351 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1352 /*
1353  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
1354  */
1355 static long __meminitdata addr_start, addr_end;
1356 static void __meminitdata *p_start, *p_end;
1357 static int __meminitdata node_start;
1358
1359 static int __meminit vmemmap_populate_hugepages(unsigned long start,
1360                 unsigned long end, int node, struct vmem_altmap *altmap)
1361 {
1362         unsigned long addr;
1363         unsigned long next;
1364         pgd_t *pgd;
1365         p4d_t *p4d;
1366         pud_t *pud;
1367         pmd_t *pmd;
1368
1369         for (addr = start; addr < end; addr = next) {
1370                 next = pmd_addr_end(addr, end);
1371
1372                 pgd = vmemmap_pgd_populate(addr, node);
1373                 if (!pgd)
1374                         return -ENOMEM;
1375
1376                 p4d = vmemmap_p4d_populate(pgd, addr, node);
1377                 if (!p4d)
1378                         return -ENOMEM;
1379
1380                 pud = vmemmap_pud_populate(p4d, addr, node);
1381                 if (!pud)
1382                         return -ENOMEM;
1383
1384                 pmd = pmd_offset(pud, addr);
1385                 if (pmd_none(*pmd)) {
1386                         void *p;
1387
1388                         if (altmap)
1389                                 p = altmap_alloc_block_buf(PMD_SIZE, altmap);
1390                         else
1391                                 p = vmemmap_alloc_block_buf(PMD_SIZE, node);
1392                         if (p) {
1393                                 pte_t entry;
1394
1395                                 entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
1396                                                 PAGE_KERNEL_LARGE);
1397                                 set_pmd(pmd, __pmd(pte_val(entry)));
1398
1399                                 /* check to see if we have contiguous blocks */
1400                                 if (p_end != p || node_start != node) {
1401                                         if (p_start)
1402                                                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1403                                                        addr_start, addr_end-1, p_start, p_end-1, node_start);
1404                                         addr_start = addr;
1405                                         node_start = node;
1406                                         p_start = p;
1407                                 }
1408
1409                                 addr_end = addr + PMD_SIZE;
1410                                 p_end = p + PMD_SIZE;
1411                                 continue;
1412                         } else if (altmap)
1413                                 return -ENOMEM; /* no fallback */
1414                 } else if (pmd_large(*pmd)) {
1415                         vmemmap_verify((pte_t *)pmd, node, addr, next);
1416                         continue;
1417                 }
1418                 if (vmemmap_populate_basepages(addr, next, node))
1419                         return -ENOMEM;
1420         }
1421         return 0;
1422 }
1423
1424 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1425                 struct vmem_altmap *altmap)
1426 {
1427         int err;
1428
1429         if (boot_cpu_has(X86_FEATURE_PSE))
1430                 err = vmemmap_populate_hugepages(start, end, node, altmap);
1431         else if (altmap) {
1432                 pr_err_once("%s: no cpu support for altmap allocations\n",
1433                                 __func__);
1434                 err = -ENOMEM;
1435         } else
1436                 err = vmemmap_populate_basepages(start, end, node);
1437         if (!err)
1438                 sync_global_pgds(start, end - 1);
1439         return err;
1440 }
1441
1442 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HAVE_BOOTMEM_INFO_NODE)
1443 void register_page_bootmem_memmap(unsigned long section_nr,
1444                                   struct page *start_page, unsigned long nr_pages)
1445 {
1446         unsigned long addr = (unsigned long)start_page;
1447         unsigned long end = (unsigned long)(start_page + nr_pages);
1448         unsigned long next;
1449         pgd_t *pgd;
1450         p4d_t *p4d;
1451         pud_t *pud;
1452         pmd_t *pmd;
1453         unsigned int nr_pmd_pages;
1454         struct page *page;
1455
1456         for (; addr < end; addr = next) {
1457                 pte_t *pte = NULL;
1458
1459                 pgd = pgd_offset_k(addr);
1460                 if (pgd_none(*pgd)) {
1461                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1462                         continue;
1463                 }
1464                 get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
1465
1466                 p4d = p4d_offset(pgd, addr);
1467                 if (p4d_none(*p4d)) {
1468                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1469                         continue;
1470                 }
1471                 get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
1472
1473                 pud = pud_offset(p4d, addr);
1474                 if (pud_none(*pud)) {
1475                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1476                         continue;
1477                 }
1478                 get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
1479
1480                 if (!boot_cpu_has(X86_FEATURE_PSE)) {
1481                         next = (addr + PAGE_SIZE) & PAGE_MASK;
1482                         pmd = pmd_offset(pud, addr);
1483                         if (pmd_none(*pmd))
1484                                 continue;
1485                         get_page_bootmem(section_nr, pmd_page(*pmd),
1486                                          MIX_SECTION_INFO);
1487
1488                         pte = pte_offset_kernel(pmd, addr);
1489                         if (pte_none(*pte))
1490                                 continue;
1491                         get_page_bootmem(section_nr, pte_page(*pte),
1492                                          SECTION_INFO);
1493                 } else {
1494                         next = pmd_addr_end(addr, end);
1495
1496                         pmd = pmd_offset(pud, addr);
1497                         if (pmd_none(*pmd))
1498                                 continue;
1499
1500                         nr_pmd_pages = 1 << get_order(PMD_SIZE);
1501                         page = pmd_page(*pmd);
1502                         while (nr_pmd_pages--)
1503                                 get_page_bootmem(section_nr, page++,
1504                                                  SECTION_INFO);
1505                 }
1506         }
1507 }
1508 #endif
1509
1510 void __meminit vmemmap_populate_print_last(void)
1511 {
1512         if (p_start) {
1513                 pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
1514                         addr_start, addr_end-1, p_start, p_end-1, node_start);
1515                 p_start = NULL;
1516                 p_end = NULL;
1517                 node_start = 0;
1518         }
1519 }
1520 #endif