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1/*
2 * sparse memory mappings.
3 */
4#include <linux/mm.h>
5#include <linux/slab.h>
6#include <linux/mmzone.h>
7#include <linux/bootmem.h>
8#include <linux/compiler.h>
9#include <linux/highmem.h>
10#include <linux/export.h>
11#include <linux/spinlock.h>
12#include <linux/vmalloc.h>
13
14#include "internal.h"
15#include <asm/dma.h>
16#include <asm/pgalloc.h>
17#include <asm/pgtable.h>
18
19/*
20 * Permanent SPARSEMEM data:
21 *
22 * 1) mem_section - memory sections, mem_map's for valid memory
23 */
24#ifdef CONFIG_SPARSEMEM_EXTREME
25struct mem_section *mem_section[NR_SECTION_ROOTS]
26 ____cacheline_internodealigned_in_smp;
27#else
28struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
29 ____cacheline_internodealigned_in_smp;
30#endif
31EXPORT_SYMBOL(mem_section);
32
33#ifdef NODE_NOT_IN_PAGE_FLAGS
34/*
35 * If we did not store the node number in the page then we have to
36 * do a lookup in the section_to_node_table in order to find which
37 * node the page belongs to.
38 */
39#if MAX_NUMNODES <= 256
40static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
41#else
42static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
43#endif
44
45int page_to_nid(const struct page *page)
46{
47 return section_to_node_table[page_to_section(page)];
48}
49EXPORT_SYMBOL(page_to_nid);
50
51static void set_section_nid(unsigned long section_nr, int nid)
52{
53 section_to_node_table[section_nr] = nid;
54}
55#else /* !NODE_NOT_IN_PAGE_FLAGS */
56static inline void set_section_nid(unsigned long section_nr, int nid)
57{
58}
59#endif
60
61#ifdef CONFIG_SPARSEMEM_EXTREME
62static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
63{
64 struct mem_section *section = NULL;
65 unsigned long array_size = SECTIONS_PER_ROOT *
66 sizeof(struct mem_section);
67
68 if (slab_is_available()) {
69 if (node_state(nid, N_HIGH_MEMORY))
70 section = kzalloc_node(array_size, GFP_KERNEL, nid);
71 else
72 section = kzalloc(array_size, GFP_KERNEL);
73 } else {
74 section = memblock_virt_alloc_node(array_size, nid);
75 }
76
77 return section;
78}
79
80static int __meminit sparse_index_init(unsigned long section_nr, int nid)
81{
82 unsigned long root = SECTION_NR_TO_ROOT(section_nr);
83 struct mem_section *section;
84
85 if (mem_section[root])
86 return -EEXIST;
87
88 section = sparse_index_alloc(nid);
89 if (!section)
90 return -ENOMEM;
91
92 mem_section[root] = section;
93
94 return 0;
95}
96#else /* !SPARSEMEM_EXTREME */
97static inline int sparse_index_init(unsigned long section_nr, int nid)
98{
99 return 0;
100}
101#endif
102
103/*
104 * Although written for the SPARSEMEM_EXTREME case, this happens
105 * to also work for the flat array case because
106 * NR_SECTION_ROOTS==NR_MEM_SECTIONS.
107 */
108int __section_nr(struct mem_section* ms)
109{
110 unsigned long root_nr;
111 struct mem_section* root;
112
113 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
114 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
115 if (!root)
116 continue;
117
118 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
119 break;
120 }
121
122 VM_BUG_ON(root_nr == NR_SECTION_ROOTS);
123
124 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
125}
126
127/*
128 * During early boot, before section_mem_map is used for an actual
129 * mem_map, we use section_mem_map to store the section's NUMA
130 * node. This keeps us from having to use another data structure. The
131 * node information is cleared just before we store the real mem_map.
132 */
133static inline unsigned long sparse_encode_early_nid(int nid)
134{
135 return (nid << SECTION_NID_SHIFT);
136}
137
138static inline int sparse_early_nid(struct mem_section *section)
139{
140 return (section->section_mem_map >> SECTION_NID_SHIFT);
141}
142
143/* Validate the physical addressing limitations of the model */
144void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
145 unsigned long *end_pfn)
146{
147 unsigned long max_sparsemem_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
148
149 /*
150 * Sanity checks - do not allow an architecture to pass
151 * in larger pfns than the maximum scope of sparsemem:
152 */
153 if (*start_pfn > max_sparsemem_pfn) {
154 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
155 "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
156 *start_pfn, *end_pfn, max_sparsemem_pfn);
157 WARN_ON_ONCE(1);
158 *start_pfn = max_sparsemem_pfn;
159 *end_pfn = max_sparsemem_pfn;
160 } else if (*end_pfn > max_sparsemem_pfn) {
161 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
162 "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
163 *start_pfn, *end_pfn, max_sparsemem_pfn);
164 WARN_ON_ONCE(1);
165 *end_pfn = max_sparsemem_pfn;
166 }
167}
168
169/* Record a memory area against a node. */
170void __init memory_present(int nid, unsigned long start, unsigned long end)
171{
172 unsigned long pfn;
173
174 start &= PAGE_SECTION_MASK;
175 mminit_validate_memmodel_limits(&start, &end);
176 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
177 unsigned long section = pfn_to_section_nr(pfn);
178 struct mem_section *ms;
179
180 sparse_index_init(section, nid);
181 set_section_nid(section, nid);
182
183 ms = __nr_to_section(section);
184 if (!ms->section_mem_map)
185 ms->section_mem_map = sparse_encode_early_nid(nid) |
186 SECTION_MARKED_PRESENT;
187 }
188}
189
190/*
191 * Only used by the i386 NUMA architecures, but relatively
192 * generic code.
193 */
194unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn,
195 unsigned long end_pfn)
196{
197 unsigned long pfn;
198 unsigned long nr_pages = 0;
199
200 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
201 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
202 if (nid != early_pfn_to_nid(pfn))
203 continue;
204
205 if (pfn_present(pfn))
206 nr_pages += PAGES_PER_SECTION;
207 }
208
209 return nr_pages * sizeof(struct page);
210}
211
212/*
213 * Subtle, we encode the real pfn into the mem_map such that
214 * the identity pfn - section_mem_map will return the actual
215 * physical page frame number.
216 */
217static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
218{
219 return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
220}
221
222/*
223 * Decode mem_map from the coded memmap
224 */
225struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
226{
227 /* mask off the extra low bits of information */
228 coded_mem_map &= SECTION_MAP_MASK;
229 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
230}
231
232static int __meminit sparse_init_one_section(struct mem_section *ms,
233 unsigned long pnum, struct page *mem_map,
234 unsigned long *pageblock_bitmap)
235{
236 if (!present_section(ms))
237 return -EINVAL;
238
239 ms->section_mem_map &= ~SECTION_MAP_MASK;
240 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) |
241 SECTION_HAS_MEM_MAP;
242 ms->pageblock_flags = pageblock_bitmap;
243
244 return 1;
245}
246
247unsigned long usemap_size(void)
248{
249 unsigned long size_bytes;
250 size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
251 size_bytes = roundup(size_bytes, sizeof(unsigned long));
252 return size_bytes;
253}
254
255#ifdef CONFIG_MEMORY_HOTPLUG
256static unsigned long *__kmalloc_section_usemap(void)
257{
258 return kmalloc(usemap_size(), GFP_KERNEL);
259}
260#endif /* CONFIG_MEMORY_HOTPLUG */
261
262#ifdef CONFIG_MEMORY_HOTREMOVE
263static unsigned long * __init
264sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
265 unsigned long size)
266{
267 unsigned long goal, limit;
268 unsigned long *p;
269 int nid;
270 /*
271 * A page may contain usemaps for other sections preventing the
272 * page being freed and making a section unremovable while
273 * other sections referencing the usemap remain active. Similarly,
274 * a pgdat can prevent a section being removed. If section A
275 * contains a pgdat and section B contains the usemap, both
276 * sections become inter-dependent. This allocates usemaps
277 * from the same section as the pgdat where possible to avoid
278 * this problem.
279 */
280 goal = __pa(pgdat) & (PAGE_SECTION_MASK << PAGE_SHIFT);
281 limit = goal + (1UL << PA_SECTION_SHIFT);
282 nid = early_pfn_to_nid(goal >> PAGE_SHIFT);
283again:
284 p = memblock_virt_alloc_try_nid_nopanic(size,
285 SMP_CACHE_BYTES, goal, limit,
286 nid);
287 if (!p && limit) {
288 limit = 0;
289 goto again;
290 }
291 return p;
292}
293
294static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
295{
296 unsigned long usemap_snr, pgdat_snr;
297 static unsigned long old_usemap_snr = NR_MEM_SECTIONS;
298 static unsigned long old_pgdat_snr = NR_MEM_SECTIONS;
299 struct pglist_data *pgdat = NODE_DATA(nid);
300 int usemap_nid;
301
302 usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
303 pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
304 if (usemap_snr == pgdat_snr)
305 return;
306
307 if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
308 /* skip redundant message */
309 return;
310
311 old_usemap_snr = usemap_snr;
312 old_pgdat_snr = pgdat_snr;
313
314 usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
315 if (usemap_nid != nid) {
316 pr_info("node %d must be removed before remove section %ld\n",
317 nid, usemap_snr);
318 return;
319 }
320 /*
321 * There is a circular dependency.
322 * Some platforms allow un-removable section because they will just
323 * gather other removable sections for dynamic partitioning.
324 * Just notify un-removable section's number here.
325 */
326 pr_info("Section %ld and %ld (node %d) have a circular dependency on usemap and pgdat allocations\n",
327 usemap_snr, pgdat_snr, nid);
328}
329#else
330static unsigned long * __init
331sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
332 unsigned long size)
333{
334 return memblock_virt_alloc_node_nopanic(size, pgdat->node_id);
335}
336
337static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
338{
339}
340#endif /* CONFIG_MEMORY_HOTREMOVE */
341
342static void __init sparse_early_usemaps_alloc_node(void *data,
343 unsigned long pnum_begin,
344 unsigned long pnum_end,
345 unsigned long usemap_count, int nodeid)
346{
347 void *usemap;
348 unsigned long pnum;
349 unsigned long **usemap_map = (unsigned long **)data;
350 int size = usemap_size();
351
352 usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
353 size * usemap_count);
354 if (!usemap) {
355 pr_warn("%s: allocation failed\n", __func__);
356 return;
357 }
358
359 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
360 if (!present_section_nr(pnum))
361 continue;
362 usemap_map[pnum] = usemap;
363 usemap += size;
364 check_usemap_section_nr(nodeid, usemap_map[pnum]);
365 }
366}
367
368#ifndef CONFIG_SPARSEMEM_VMEMMAP
369struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
370{
371 struct page *map;
372 unsigned long size;
373
374 map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
375 if (map)
376 return map;
377
378 size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
379 map = memblock_virt_alloc_try_nid(size,
380 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
381 BOOTMEM_ALLOC_ACCESSIBLE, nid);
382 return map;
383}
384void __init sparse_mem_maps_populate_node(struct page **map_map,
385 unsigned long pnum_begin,
386 unsigned long pnum_end,
387 unsigned long map_count, int nodeid)
388{
389 void *map;
390 unsigned long pnum;
391 unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
392
393 map = alloc_remap(nodeid, size * map_count);
394 if (map) {
395 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
396 if (!present_section_nr(pnum))
397 continue;
398 map_map[pnum] = map;
399 map += size;
400 }
401 return;
402 }
403
404 size = PAGE_ALIGN(size);
405 map = memblock_virt_alloc_try_nid(size * map_count,
406 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
407 BOOTMEM_ALLOC_ACCESSIBLE, nodeid);
408 if (map) {
409 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
410 if (!present_section_nr(pnum))
411 continue;
412 map_map[pnum] = map;
413 map += size;
414 }
415 return;
416 }
417
418 /* fallback */
419 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
420 struct mem_section *ms;
421
422 if (!present_section_nr(pnum))
423 continue;
424 map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
425 if (map_map[pnum])
426 continue;
427 ms = __nr_to_section(pnum);
428 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
429 __func__);
430 ms->section_mem_map = 0;
431 }
432}
433#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
434
435#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
436static void __init sparse_early_mem_maps_alloc_node(void *data,
437 unsigned long pnum_begin,
438 unsigned long pnum_end,
439 unsigned long map_count, int nodeid)
440{
441 struct page **map_map = (struct page **)data;
442 sparse_mem_maps_populate_node(map_map, pnum_begin, pnum_end,
443 map_count, nodeid);
444}
445#else
446static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
447{
448 struct page *map;
449 struct mem_section *ms = __nr_to_section(pnum);
450 int nid = sparse_early_nid(ms);
451
452 map = sparse_mem_map_populate(pnum, nid);
453 if (map)
454 return map;
455
456 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
457 __func__);
458 ms->section_mem_map = 0;
459 return NULL;
460}
461#endif
462
463void __weak __meminit vmemmap_populate_print_last(void)
464{
465}
466
467/**
468 * alloc_usemap_and_memmap - memory alloction for pageblock flags and vmemmap
469 * @map: usemap_map for pageblock flags or mmap_map for vmemmap
470 */
471static void __init alloc_usemap_and_memmap(void (*alloc_func)
472 (void *, unsigned long, unsigned long,
473 unsigned long, int), void *data)
474{
475 unsigned long pnum;
476 unsigned long map_count;
477 int nodeid_begin = 0;
478 unsigned long pnum_begin = 0;
479
480 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
481 struct mem_section *ms;
482
483 if (!present_section_nr(pnum))
484 continue;
485 ms = __nr_to_section(pnum);
486 nodeid_begin = sparse_early_nid(ms);
487 pnum_begin = pnum;
488 break;
489 }
490 map_count = 1;
491 for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
492 struct mem_section *ms;
493 int nodeid;
494
495 if (!present_section_nr(pnum))
496 continue;
497 ms = __nr_to_section(pnum);
498 nodeid = sparse_early_nid(ms);
499 if (nodeid == nodeid_begin) {
500 map_count++;
501 continue;
502 }
503 /* ok, we need to take cake of from pnum_begin to pnum - 1*/
504 alloc_func(data, pnum_begin, pnum,
505 map_count, nodeid_begin);
506 /* new start, update count etc*/
507 nodeid_begin = nodeid;
508 pnum_begin = pnum;
509 map_count = 1;
510 }
511 /* ok, last chunk */
512 alloc_func(data, pnum_begin, NR_MEM_SECTIONS,
513 map_count, nodeid_begin);
514}
515
516/*
517 * Allocate the accumulated non-linear sections, allocate a mem_map
518 * for each and record the physical to section mapping.
519 */
520void __init sparse_init(void)
521{
522 unsigned long pnum;
523 struct page *map;
524 unsigned long *usemap;
525 unsigned long **usemap_map;
526 int size;
527#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
528 int size2;
529 struct page **map_map;
530#endif
531
532 /* see include/linux/mmzone.h 'struct mem_section' definition */
533 BUILD_BUG_ON(!is_power_of_2(sizeof(struct mem_section)));
534
535 /* Setup pageblock_order for HUGETLB_PAGE_SIZE_VARIABLE */
536 set_pageblock_order();
537
538 /*
539 * map is using big page (aka 2M in x86 64 bit)
540 * usemap is less one page (aka 24 bytes)
541 * so alloc 2M (with 2M align) and 24 bytes in turn will
542 * make next 2M slip to one more 2M later.
543 * then in big system, the memory will have a lot of holes...
544 * here try to allocate 2M pages continuously.
545 *
546 * powerpc need to call sparse_init_one_section right after each
547 * sparse_early_mem_map_alloc, so allocate usemap_map at first.
548 */
549 size = sizeof(unsigned long *) * NR_MEM_SECTIONS;
550 usemap_map = memblock_virt_alloc(size, 0);
551 if (!usemap_map)
552 panic("can not allocate usemap_map\n");
553 alloc_usemap_and_memmap(sparse_early_usemaps_alloc_node,
554 (void *)usemap_map);
555
556#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
557 size2 = sizeof(struct page *) * NR_MEM_SECTIONS;
558 map_map = memblock_virt_alloc(size2, 0);
559 if (!map_map)
560 panic("can not allocate map_map\n");
561 alloc_usemap_and_memmap(sparse_early_mem_maps_alloc_node,
562 (void *)map_map);
563#endif
564
565 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
566 if (!present_section_nr(pnum))
567 continue;
568
569 usemap = usemap_map[pnum];
570 if (!usemap)
571 continue;
572
573#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
574 map = map_map[pnum];
575#else
576 map = sparse_early_mem_map_alloc(pnum);
577#endif
578 if (!map)
579 continue;
580
581 sparse_init_one_section(__nr_to_section(pnum), pnum, map,
582 usemap);
583 }
584
585 vmemmap_populate_print_last();
586
587#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
588 memblock_free_early(__pa(map_map), size2);
589#endif
590 memblock_free_early(__pa(usemap_map), size);
591}
592
593#ifdef CONFIG_MEMORY_HOTPLUG
594#ifdef CONFIG_SPARSEMEM_VMEMMAP
595static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
596{
597 /* This will make the necessary allocations eventually. */
598 return sparse_mem_map_populate(pnum, nid);
599}
600static void __kfree_section_memmap(struct page *memmap)
601{
602 unsigned long start = (unsigned long)memmap;
603 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
604
605 vmemmap_free(start, end);
606}
607#ifdef CONFIG_MEMORY_HOTREMOVE
608static void free_map_bootmem(struct page *memmap)
609{
610 unsigned long start = (unsigned long)memmap;
611 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
612
613 vmemmap_free(start, end);
614}
615#endif /* CONFIG_MEMORY_HOTREMOVE */
616#else
617static struct page *__kmalloc_section_memmap(void)
618{
619 struct page *page, *ret;
620 unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION;
621
622 page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
623 if (page)
624 goto got_map_page;
625
626 ret = vmalloc(memmap_size);
627 if (ret)
628 goto got_map_ptr;
629
630 return NULL;
631got_map_page:
632 ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
633got_map_ptr:
634
635 return ret;
636}
637
638static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
639{
640 return __kmalloc_section_memmap();
641}
642
643static void __kfree_section_memmap(struct page *memmap)
644{
645 if (is_vmalloc_addr(memmap))
646 vfree(memmap);
647 else
648 free_pages((unsigned long)memmap,
649 get_order(sizeof(struct page) * PAGES_PER_SECTION));
650}
651
652#ifdef CONFIG_MEMORY_HOTREMOVE
653static void free_map_bootmem(struct page *memmap)
654{
655 unsigned long maps_section_nr, removing_section_nr, i;
656 unsigned long magic, nr_pages;
657 struct page *page = virt_to_page(memmap);
658
659 nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
660 >> PAGE_SHIFT;
661
662 for (i = 0; i < nr_pages; i++, page++) {
663 magic = (unsigned long) page->lru.next;
664
665 BUG_ON(magic == NODE_INFO);
666
667 maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
668 removing_section_nr = page->private;
669
670 /*
671 * When this function is called, the removing section is
672 * logical offlined state. This means all pages are isolated
673 * from page allocator. If removing section's memmap is placed
674 * on the same section, it must not be freed.
675 * If it is freed, page allocator may allocate it which will
676 * be removed physically soon.
677 */
678 if (maps_section_nr != removing_section_nr)
679 put_page_bootmem(page);
680 }
681}
682#endif /* CONFIG_MEMORY_HOTREMOVE */
683#endif /* CONFIG_SPARSEMEM_VMEMMAP */
684
685/*
686 * returns the number of sections whose mem_maps were properly
687 * set. If this is <=0, then that means that the passed-in
688 * map was not consumed and must be freed.
689 */
690int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn)
691{
692 unsigned long section_nr = pfn_to_section_nr(start_pfn);
693 struct pglist_data *pgdat = zone->zone_pgdat;
694 struct mem_section *ms;
695 struct page *memmap;
696 unsigned long *usemap;
697 unsigned long flags;
698 int ret;
699
700 /*
701 * no locking for this, because it does its own
702 * plus, it does a kmalloc
703 */
704 ret = sparse_index_init(section_nr, pgdat->node_id);
705 if (ret < 0 && ret != -EEXIST)
706 return ret;
707 memmap = kmalloc_section_memmap(section_nr, pgdat->node_id);
708 if (!memmap)
709 return -ENOMEM;
710 usemap = __kmalloc_section_usemap();
711 if (!usemap) {
712 __kfree_section_memmap(memmap);
713 return -ENOMEM;
714 }
715
716 pgdat_resize_lock(pgdat, &flags);
717
718 ms = __pfn_to_section(start_pfn);
719 if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
720 ret = -EEXIST;
721 goto out;
722 }
723
724 memset(memmap, 0, sizeof(struct page) * PAGES_PER_SECTION);
725
726 ms->section_mem_map |= SECTION_MARKED_PRESENT;
727
728 ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
729
730out:
731 pgdat_resize_unlock(pgdat, &flags);
732 if (ret <= 0) {
733 kfree(usemap);
734 __kfree_section_memmap(memmap);
735 }
736 return ret;
737}
738
739#ifdef CONFIG_MEMORY_HOTREMOVE
740#ifdef CONFIG_MEMORY_FAILURE
741static void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
742{
743 int i;
744
745 if (!memmap)
746 return;
747
748 for (i = 0; i < nr_pages; i++) {
749 if (PageHWPoison(&memmap[i])) {
750 atomic_long_sub(1, &num_poisoned_pages);
751 ClearPageHWPoison(&memmap[i]);
752 }
753 }
754}
755#else
756static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
757{
758}
759#endif
760
761static void free_section_usemap(struct page *memmap, unsigned long *usemap)
762{
763 struct page *usemap_page;
764
765 if (!usemap)
766 return;
767
768 usemap_page = virt_to_page(usemap);
769 /*
770 * Check to see if allocation came from hot-plug-add
771 */
772 if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
773 kfree(usemap);
774 if (memmap)
775 __kfree_section_memmap(memmap);
776 return;
777 }
778
779 /*
780 * The usemap came from bootmem. This is packed with other usemaps
781 * on the section which has pgdat at boot time. Just keep it as is now.
782 */
783
784 if (memmap)
785 free_map_bootmem(memmap);
786}
787
788void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
789 unsigned long map_offset)
790{
791 struct page *memmap = NULL;
792 unsigned long *usemap = NULL, flags;
793 struct pglist_data *pgdat = zone->zone_pgdat;
794
795 pgdat_resize_lock(pgdat, &flags);
796 if (ms->section_mem_map) {
797 usemap = ms->pageblock_flags;
798 memmap = sparse_decode_mem_map(ms->section_mem_map,
799 __section_nr(ms));
800 ms->section_mem_map = 0;
801 ms->pageblock_flags = NULL;
802 }
803 pgdat_resize_unlock(pgdat, &flags);
804
805 clear_hwpoisoned_pages(memmap + map_offset,
806 PAGES_PER_SECTION - map_offset);
807 free_section_usemap(memmap, usemap);
808}
809#endif /* CONFIG_MEMORY_HOTREMOVE */
810#endif /* CONFIG_MEMORY_HOTPLUG */
1/*
2 * sparse memory mappings.
3 */
4#include <linux/mm.h>
5#include <linux/slab.h>
6#include <linux/mmzone.h>
7#include <linux/bootmem.h>
8#include <linux/compiler.h>
9#include <linux/highmem.h>
10#include <linux/export.h>
11#include <linux/spinlock.h>
12#include <linux/vmalloc.h>
13
14#include "internal.h"
15#include <asm/dma.h>
16#include <asm/pgalloc.h>
17#include <asm/pgtable.h>
18
19/*
20 * Permanent SPARSEMEM data:
21 *
22 * 1) mem_section - memory sections, mem_map's for valid memory
23 */
24#ifdef CONFIG_SPARSEMEM_EXTREME
25struct mem_section *mem_section[NR_SECTION_ROOTS]
26 ____cacheline_internodealigned_in_smp;
27#else
28struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
29 ____cacheline_internodealigned_in_smp;
30#endif
31EXPORT_SYMBOL(mem_section);
32
33#ifdef NODE_NOT_IN_PAGE_FLAGS
34/*
35 * If we did not store the node number in the page then we have to
36 * do a lookup in the section_to_node_table in order to find which
37 * node the page belongs to.
38 */
39#if MAX_NUMNODES <= 256
40static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
41#else
42static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
43#endif
44
45int page_to_nid(const struct page *page)
46{
47 return section_to_node_table[page_to_section(page)];
48}
49EXPORT_SYMBOL(page_to_nid);
50
51static void set_section_nid(unsigned long section_nr, int nid)
52{
53 section_to_node_table[section_nr] = nid;
54}
55#else /* !NODE_NOT_IN_PAGE_FLAGS */
56static inline void set_section_nid(unsigned long section_nr, int nid)
57{
58}
59#endif
60
61#ifdef CONFIG_SPARSEMEM_EXTREME
62static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
63{
64 struct mem_section *section = NULL;
65 unsigned long array_size = SECTIONS_PER_ROOT *
66 sizeof(struct mem_section);
67
68 if (slab_is_available()) {
69 if (node_state(nid, N_HIGH_MEMORY))
70 section = kzalloc_node(array_size, GFP_KERNEL, nid);
71 else
72 section = kzalloc(array_size, GFP_KERNEL);
73 } else {
74 section = memblock_virt_alloc_node(array_size, nid);
75 }
76
77 return section;
78}
79
80static int __meminit sparse_index_init(unsigned long section_nr, int nid)
81{
82 unsigned long root = SECTION_NR_TO_ROOT(section_nr);
83 struct mem_section *section;
84
85 if (mem_section[root])
86 return -EEXIST;
87
88 section = sparse_index_alloc(nid);
89 if (!section)
90 return -ENOMEM;
91
92 mem_section[root] = section;
93
94 return 0;
95}
96#else /* !SPARSEMEM_EXTREME */
97static inline int sparse_index_init(unsigned long section_nr, int nid)
98{
99 return 0;
100}
101#endif
102
103/*
104 * Although written for the SPARSEMEM_EXTREME case, this happens
105 * to also work for the flat array case because
106 * NR_SECTION_ROOTS==NR_MEM_SECTIONS.
107 */
108int __section_nr(struct mem_section* ms)
109{
110 unsigned long root_nr;
111 struct mem_section* root;
112
113 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
114 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
115 if (!root)
116 continue;
117
118 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
119 break;
120 }
121
122 VM_BUG_ON(root_nr == NR_SECTION_ROOTS);
123
124 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
125}
126
127/*
128 * During early boot, before section_mem_map is used for an actual
129 * mem_map, we use section_mem_map to store the section's NUMA
130 * node. This keeps us from having to use another data structure. The
131 * node information is cleared just before we store the real mem_map.
132 */
133static inline unsigned long sparse_encode_early_nid(int nid)
134{
135 return (nid << SECTION_NID_SHIFT);
136}
137
138static inline int sparse_early_nid(struct mem_section *section)
139{
140 return (section->section_mem_map >> SECTION_NID_SHIFT);
141}
142
143/* Validate the physical addressing limitations of the model */
144void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
145 unsigned long *end_pfn)
146{
147 unsigned long max_sparsemem_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
148
149 /*
150 * Sanity checks - do not allow an architecture to pass
151 * in larger pfns than the maximum scope of sparsemem:
152 */
153 if (*start_pfn > max_sparsemem_pfn) {
154 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
155 "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
156 *start_pfn, *end_pfn, max_sparsemem_pfn);
157 WARN_ON_ONCE(1);
158 *start_pfn = max_sparsemem_pfn;
159 *end_pfn = max_sparsemem_pfn;
160 } else if (*end_pfn > max_sparsemem_pfn) {
161 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
162 "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
163 *start_pfn, *end_pfn, max_sparsemem_pfn);
164 WARN_ON_ONCE(1);
165 *end_pfn = max_sparsemem_pfn;
166 }
167}
168
169/* Record a memory area against a node. */
170void __init memory_present(int nid, unsigned long start, unsigned long end)
171{
172 unsigned long pfn;
173
174 start &= PAGE_SECTION_MASK;
175 mminit_validate_memmodel_limits(&start, &end);
176 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
177 unsigned long section = pfn_to_section_nr(pfn);
178 struct mem_section *ms;
179
180 sparse_index_init(section, nid);
181 set_section_nid(section, nid);
182
183 ms = __nr_to_section(section);
184 if (!ms->section_mem_map)
185 ms->section_mem_map = sparse_encode_early_nid(nid) |
186 SECTION_MARKED_PRESENT;
187 }
188}
189
190/*
191 * Only used by the i386 NUMA architecures, but relatively
192 * generic code.
193 */
194unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn,
195 unsigned long end_pfn)
196{
197 unsigned long pfn;
198 unsigned long nr_pages = 0;
199
200 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
201 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
202 if (nid != early_pfn_to_nid(pfn))
203 continue;
204
205 if (pfn_present(pfn))
206 nr_pages += PAGES_PER_SECTION;
207 }
208
209 return nr_pages * sizeof(struct page);
210}
211
212/*
213 * Subtle, we encode the real pfn into the mem_map such that
214 * the identity pfn - section_mem_map will return the actual
215 * physical page frame number.
216 */
217static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
218{
219 return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
220}
221
222/*
223 * Decode mem_map from the coded memmap
224 */
225struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
226{
227 /* mask off the extra low bits of information */
228 coded_mem_map &= SECTION_MAP_MASK;
229 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
230}
231
232static int __meminit sparse_init_one_section(struct mem_section *ms,
233 unsigned long pnum, struct page *mem_map,
234 unsigned long *pageblock_bitmap)
235{
236 if (!present_section(ms))
237 return -EINVAL;
238
239 ms->section_mem_map &= ~SECTION_MAP_MASK;
240 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) |
241 SECTION_HAS_MEM_MAP;
242 ms->pageblock_flags = pageblock_bitmap;
243
244 return 1;
245}
246
247unsigned long usemap_size(void)
248{
249 unsigned long size_bytes;
250 size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
251 size_bytes = roundup(size_bytes, sizeof(unsigned long));
252 return size_bytes;
253}
254
255#ifdef CONFIG_MEMORY_HOTPLUG
256static unsigned long *__kmalloc_section_usemap(void)
257{
258 return kmalloc(usemap_size(), GFP_KERNEL);
259}
260#endif /* CONFIG_MEMORY_HOTPLUG */
261
262#ifdef CONFIG_MEMORY_HOTREMOVE
263static unsigned long * __init
264sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
265 unsigned long size)
266{
267 unsigned long goal, limit;
268 unsigned long *p;
269 int nid;
270 /*
271 * A page may contain usemaps for other sections preventing the
272 * page being freed and making a section unremovable while
273 * other sections referencing the usemap remain active. Similarly,
274 * a pgdat can prevent a section being removed. If section A
275 * contains a pgdat and section B contains the usemap, both
276 * sections become inter-dependent. This allocates usemaps
277 * from the same section as the pgdat where possible to avoid
278 * this problem.
279 */
280 goal = __pa(pgdat) & (PAGE_SECTION_MASK << PAGE_SHIFT);
281 limit = goal + (1UL << PA_SECTION_SHIFT);
282 nid = early_pfn_to_nid(goal >> PAGE_SHIFT);
283again:
284 p = memblock_virt_alloc_try_nid_nopanic(size,
285 SMP_CACHE_BYTES, goal, limit,
286 nid);
287 if (!p && limit) {
288 limit = 0;
289 goto again;
290 }
291 return p;
292}
293
294static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
295{
296 unsigned long usemap_snr, pgdat_snr;
297 static unsigned long old_usemap_snr = NR_MEM_SECTIONS;
298 static unsigned long old_pgdat_snr = NR_MEM_SECTIONS;
299 struct pglist_data *pgdat = NODE_DATA(nid);
300 int usemap_nid;
301
302 usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
303 pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
304 if (usemap_snr == pgdat_snr)
305 return;
306
307 if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
308 /* skip redundant message */
309 return;
310
311 old_usemap_snr = usemap_snr;
312 old_pgdat_snr = pgdat_snr;
313
314 usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
315 if (usemap_nid != nid) {
316 printk(KERN_INFO
317 "node %d must be removed before remove section %ld\n",
318 nid, usemap_snr);
319 return;
320 }
321 /*
322 * There is a circular dependency.
323 * Some platforms allow un-removable section because they will just
324 * gather other removable sections for dynamic partitioning.
325 * Just notify un-removable section's number here.
326 */
327 printk(KERN_INFO "Section %ld and %ld (node %d)", usemap_snr,
328 pgdat_snr, nid);
329 printk(KERN_CONT
330 " have a circular dependency on usemap and pgdat allocations\n");
331}
332#else
333static unsigned long * __init
334sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
335 unsigned long size)
336{
337 return memblock_virt_alloc_node_nopanic(size, pgdat->node_id);
338}
339
340static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
341{
342}
343#endif /* CONFIG_MEMORY_HOTREMOVE */
344
345static void __init sparse_early_usemaps_alloc_node(void *data,
346 unsigned long pnum_begin,
347 unsigned long pnum_end,
348 unsigned long usemap_count, int nodeid)
349{
350 void *usemap;
351 unsigned long pnum;
352 unsigned long **usemap_map = (unsigned long **)data;
353 int size = usemap_size();
354
355 usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
356 size * usemap_count);
357 if (!usemap) {
358 printk(KERN_WARNING "%s: allocation failed\n", __func__);
359 return;
360 }
361
362 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
363 if (!present_section_nr(pnum))
364 continue;
365 usemap_map[pnum] = usemap;
366 usemap += size;
367 check_usemap_section_nr(nodeid, usemap_map[pnum]);
368 }
369}
370
371#ifndef CONFIG_SPARSEMEM_VMEMMAP
372struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
373{
374 struct page *map;
375 unsigned long size;
376
377 map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
378 if (map)
379 return map;
380
381 size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
382 map = memblock_virt_alloc_try_nid(size,
383 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
384 BOOTMEM_ALLOC_ACCESSIBLE, nid);
385 return map;
386}
387void __init sparse_mem_maps_populate_node(struct page **map_map,
388 unsigned long pnum_begin,
389 unsigned long pnum_end,
390 unsigned long map_count, int nodeid)
391{
392 void *map;
393 unsigned long pnum;
394 unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
395
396 map = alloc_remap(nodeid, size * map_count);
397 if (map) {
398 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
399 if (!present_section_nr(pnum))
400 continue;
401 map_map[pnum] = map;
402 map += size;
403 }
404 return;
405 }
406
407 size = PAGE_ALIGN(size);
408 map = memblock_virt_alloc_try_nid(size * map_count,
409 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
410 BOOTMEM_ALLOC_ACCESSIBLE, nodeid);
411 if (map) {
412 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
413 if (!present_section_nr(pnum))
414 continue;
415 map_map[pnum] = map;
416 map += size;
417 }
418 return;
419 }
420
421 /* fallback */
422 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
423 struct mem_section *ms;
424
425 if (!present_section_nr(pnum))
426 continue;
427 map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
428 if (map_map[pnum])
429 continue;
430 ms = __nr_to_section(pnum);
431 printk(KERN_ERR "%s: sparsemem memory map backing failed "
432 "some memory will not be available.\n", __func__);
433 ms->section_mem_map = 0;
434 }
435}
436#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
437
438#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
439static void __init sparse_early_mem_maps_alloc_node(void *data,
440 unsigned long pnum_begin,
441 unsigned long pnum_end,
442 unsigned long map_count, int nodeid)
443{
444 struct page **map_map = (struct page **)data;
445 sparse_mem_maps_populate_node(map_map, pnum_begin, pnum_end,
446 map_count, nodeid);
447}
448#else
449static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
450{
451 struct page *map;
452 struct mem_section *ms = __nr_to_section(pnum);
453 int nid = sparse_early_nid(ms);
454
455 map = sparse_mem_map_populate(pnum, nid);
456 if (map)
457 return map;
458
459 printk(KERN_ERR "%s: sparsemem memory map backing failed "
460 "some memory will not be available.\n", __func__);
461 ms->section_mem_map = 0;
462 return NULL;
463}
464#endif
465
466void __weak __meminit vmemmap_populate_print_last(void)
467{
468}
469
470/**
471 * alloc_usemap_and_memmap - memory alloction for pageblock flags and vmemmap
472 * @map: usemap_map for pageblock flags or mmap_map for vmemmap
473 */
474static void __init alloc_usemap_and_memmap(void (*alloc_func)
475 (void *, unsigned long, unsigned long,
476 unsigned long, int), void *data)
477{
478 unsigned long pnum;
479 unsigned long map_count;
480 int nodeid_begin = 0;
481 unsigned long pnum_begin = 0;
482
483 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
484 struct mem_section *ms;
485
486 if (!present_section_nr(pnum))
487 continue;
488 ms = __nr_to_section(pnum);
489 nodeid_begin = sparse_early_nid(ms);
490 pnum_begin = pnum;
491 break;
492 }
493 map_count = 1;
494 for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
495 struct mem_section *ms;
496 int nodeid;
497
498 if (!present_section_nr(pnum))
499 continue;
500 ms = __nr_to_section(pnum);
501 nodeid = sparse_early_nid(ms);
502 if (nodeid == nodeid_begin) {
503 map_count++;
504 continue;
505 }
506 /* ok, we need to take cake of from pnum_begin to pnum - 1*/
507 alloc_func(data, pnum_begin, pnum,
508 map_count, nodeid_begin);
509 /* new start, update count etc*/
510 nodeid_begin = nodeid;
511 pnum_begin = pnum;
512 map_count = 1;
513 }
514 /* ok, last chunk */
515 alloc_func(data, pnum_begin, NR_MEM_SECTIONS,
516 map_count, nodeid_begin);
517}
518
519/*
520 * Allocate the accumulated non-linear sections, allocate a mem_map
521 * for each and record the physical to section mapping.
522 */
523void __init sparse_init(void)
524{
525 unsigned long pnum;
526 struct page *map;
527 unsigned long *usemap;
528 unsigned long **usemap_map;
529 int size;
530#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
531 int size2;
532 struct page **map_map;
533#endif
534
535 /* see include/linux/mmzone.h 'struct mem_section' definition */
536 BUILD_BUG_ON(!is_power_of_2(sizeof(struct mem_section)));
537
538 /* Setup pageblock_order for HUGETLB_PAGE_SIZE_VARIABLE */
539 set_pageblock_order();
540
541 /*
542 * map is using big page (aka 2M in x86 64 bit)
543 * usemap is less one page (aka 24 bytes)
544 * so alloc 2M (with 2M align) and 24 bytes in turn will
545 * make next 2M slip to one more 2M later.
546 * then in big system, the memory will have a lot of holes...
547 * here try to allocate 2M pages continuously.
548 *
549 * powerpc need to call sparse_init_one_section right after each
550 * sparse_early_mem_map_alloc, so allocate usemap_map at first.
551 */
552 size = sizeof(unsigned long *) * NR_MEM_SECTIONS;
553 usemap_map = memblock_virt_alloc(size, 0);
554 if (!usemap_map)
555 panic("can not allocate usemap_map\n");
556 alloc_usemap_and_memmap(sparse_early_usemaps_alloc_node,
557 (void *)usemap_map);
558
559#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
560 size2 = sizeof(struct page *) * NR_MEM_SECTIONS;
561 map_map = memblock_virt_alloc(size2, 0);
562 if (!map_map)
563 panic("can not allocate map_map\n");
564 alloc_usemap_and_memmap(sparse_early_mem_maps_alloc_node,
565 (void *)map_map);
566#endif
567
568 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
569 if (!present_section_nr(pnum))
570 continue;
571
572 usemap = usemap_map[pnum];
573 if (!usemap)
574 continue;
575
576#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
577 map = map_map[pnum];
578#else
579 map = sparse_early_mem_map_alloc(pnum);
580#endif
581 if (!map)
582 continue;
583
584 sparse_init_one_section(__nr_to_section(pnum), pnum, map,
585 usemap);
586 }
587
588 vmemmap_populate_print_last();
589
590#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
591 memblock_free_early(__pa(map_map), size2);
592#endif
593 memblock_free_early(__pa(usemap_map), size);
594}
595
596#ifdef CONFIG_MEMORY_HOTPLUG
597#ifdef CONFIG_SPARSEMEM_VMEMMAP
598static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
599{
600 /* This will make the necessary allocations eventually. */
601 return sparse_mem_map_populate(pnum, nid);
602}
603static void __kfree_section_memmap(struct page *memmap)
604{
605 unsigned long start = (unsigned long)memmap;
606 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
607
608 vmemmap_free(start, end);
609}
610#ifdef CONFIG_MEMORY_HOTREMOVE
611static void free_map_bootmem(struct page *memmap)
612{
613 unsigned long start = (unsigned long)memmap;
614 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
615
616 vmemmap_free(start, end);
617}
618#endif /* CONFIG_MEMORY_HOTREMOVE */
619#else
620static struct page *__kmalloc_section_memmap(void)
621{
622 struct page *page, *ret;
623 unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION;
624
625 page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
626 if (page)
627 goto got_map_page;
628
629 ret = vmalloc(memmap_size);
630 if (ret)
631 goto got_map_ptr;
632
633 return NULL;
634got_map_page:
635 ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
636got_map_ptr:
637
638 return ret;
639}
640
641static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
642{
643 return __kmalloc_section_memmap();
644}
645
646static void __kfree_section_memmap(struct page *memmap)
647{
648 if (is_vmalloc_addr(memmap))
649 vfree(memmap);
650 else
651 free_pages((unsigned long)memmap,
652 get_order(sizeof(struct page) * PAGES_PER_SECTION));
653}
654
655#ifdef CONFIG_MEMORY_HOTREMOVE
656static void free_map_bootmem(struct page *memmap)
657{
658 unsigned long maps_section_nr, removing_section_nr, i;
659 unsigned long magic, nr_pages;
660 struct page *page = virt_to_page(memmap);
661
662 nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
663 >> PAGE_SHIFT;
664
665 for (i = 0; i < nr_pages; i++, page++) {
666 magic = (unsigned long) page->lru.next;
667
668 BUG_ON(magic == NODE_INFO);
669
670 maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
671 removing_section_nr = page->private;
672
673 /*
674 * When this function is called, the removing section is
675 * logical offlined state. This means all pages are isolated
676 * from page allocator. If removing section's memmap is placed
677 * on the same section, it must not be freed.
678 * If it is freed, page allocator may allocate it which will
679 * be removed physically soon.
680 */
681 if (maps_section_nr != removing_section_nr)
682 put_page_bootmem(page);
683 }
684}
685#endif /* CONFIG_MEMORY_HOTREMOVE */
686#endif /* CONFIG_SPARSEMEM_VMEMMAP */
687
688/*
689 * returns the number of sections whose mem_maps were properly
690 * set. If this is <=0, then that means that the passed-in
691 * map was not consumed and must be freed.
692 */
693int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn)
694{
695 unsigned long section_nr = pfn_to_section_nr(start_pfn);
696 struct pglist_data *pgdat = zone->zone_pgdat;
697 struct mem_section *ms;
698 struct page *memmap;
699 unsigned long *usemap;
700 unsigned long flags;
701 int ret;
702
703 /*
704 * no locking for this, because it does its own
705 * plus, it does a kmalloc
706 */
707 ret = sparse_index_init(section_nr, pgdat->node_id);
708 if (ret < 0 && ret != -EEXIST)
709 return ret;
710 memmap = kmalloc_section_memmap(section_nr, pgdat->node_id);
711 if (!memmap)
712 return -ENOMEM;
713 usemap = __kmalloc_section_usemap();
714 if (!usemap) {
715 __kfree_section_memmap(memmap);
716 return -ENOMEM;
717 }
718
719 pgdat_resize_lock(pgdat, &flags);
720
721 ms = __pfn_to_section(start_pfn);
722 if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
723 ret = -EEXIST;
724 goto out;
725 }
726
727 memset(memmap, 0, sizeof(struct page) * PAGES_PER_SECTION);
728
729 ms->section_mem_map |= SECTION_MARKED_PRESENT;
730
731 ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
732
733out:
734 pgdat_resize_unlock(pgdat, &flags);
735 if (ret <= 0) {
736 kfree(usemap);
737 __kfree_section_memmap(memmap);
738 }
739 return ret;
740}
741
742#ifdef CONFIG_MEMORY_HOTREMOVE
743#ifdef CONFIG_MEMORY_FAILURE
744static void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
745{
746 int i;
747
748 if (!memmap)
749 return;
750
751 for (i = 0; i < PAGES_PER_SECTION; i++) {
752 if (PageHWPoison(&memmap[i])) {
753 atomic_long_sub(1, &num_poisoned_pages);
754 ClearPageHWPoison(&memmap[i]);
755 }
756 }
757}
758#else
759static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
760{
761}
762#endif
763
764static void free_section_usemap(struct page *memmap, unsigned long *usemap)
765{
766 struct page *usemap_page;
767
768 if (!usemap)
769 return;
770
771 usemap_page = virt_to_page(usemap);
772 /*
773 * Check to see if allocation came from hot-plug-add
774 */
775 if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
776 kfree(usemap);
777 if (memmap)
778 __kfree_section_memmap(memmap);
779 return;
780 }
781
782 /*
783 * The usemap came from bootmem. This is packed with other usemaps
784 * on the section which has pgdat at boot time. Just keep it as is now.
785 */
786
787 if (memmap)
788 free_map_bootmem(memmap);
789}
790
791void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
792{
793 struct page *memmap = NULL;
794 unsigned long *usemap = NULL, flags;
795 struct pglist_data *pgdat = zone->zone_pgdat;
796
797 pgdat_resize_lock(pgdat, &flags);
798 if (ms->section_mem_map) {
799 usemap = ms->pageblock_flags;
800 memmap = sparse_decode_mem_map(ms->section_mem_map,
801 __section_nr(ms));
802 ms->section_mem_map = 0;
803 ms->pageblock_flags = NULL;
804 }
805 pgdat_resize_unlock(pgdat, &flags);
806
807 clear_hwpoisoned_pages(memmap, PAGES_PER_SECTION);
808 free_section_usemap(memmap, usemap);
809}
810#endif /* CONFIG_MEMORY_HOTREMOVE */
811#endif /* CONFIG_MEMORY_HOTPLUG */