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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * sparse memory mappings.
4 */
5#include <linux/mm.h>
6#include <linux/slab.h>
7#include <linux/mmzone.h>
8#include <linux/bootmem.h>
9#include <linux/compiler.h>
10#include <linux/highmem.h>
11#include <linux/export.h>
12#include <linux/spinlock.h>
13#include <linux/vmalloc.h>
14
15#include "internal.h"
16#include <asm/dma.h>
17#include <asm/pgalloc.h>
18#include <asm/pgtable.h>
19
20/*
21 * Permanent SPARSEMEM data:
22 *
23 * 1) mem_section - memory sections, mem_map's for valid memory
24 */
25#ifdef CONFIG_SPARSEMEM_EXTREME
26struct mem_section **mem_section;
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 noinline struct mem_section __ref *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 section = kzalloc_node(array_size, GFP_KERNEL, nid);
70 else
71 section = memblock_virt_alloc_node(array_size, nid);
72
73 return section;
74}
75
76static int __meminit sparse_index_init(unsigned long section_nr, int nid)
77{
78 unsigned long root = SECTION_NR_TO_ROOT(section_nr);
79 struct mem_section *section;
80
81 if (mem_section[root])
82 return -EEXIST;
83
84 section = sparse_index_alloc(nid);
85 if (!section)
86 return -ENOMEM;
87
88 mem_section[root] = section;
89
90 return 0;
91}
92#else /* !SPARSEMEM_EXTREME */
93static inline int sparse_index_init(unsigned long section_nr, int nid)
94{
95 return 0;
96}
97#endif
98
99#ifdef CONFIG_SPARSEMEM_EXTREME
100int __section_nr(struct mem_section* ms)
101{
102 unsigned long root_nr;
103 struct mem_section *root = NULL;
104
105 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
106 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
107 if (!root)
108 continue;
109
110 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
111 break;
112 }
113
114 VM_BUG_ON(!root);
115
116 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
117}
118#else
119int __section_nr(struct mem_section* ms)
120{
121 return (int)(ms - mem_section[0]);
122}
123#endif
124
125/*
126 * During early boot, before section_mem_map is used for an actual
127 * mem_map, we use section_mem_map to store the section's NUMA
128 * node. This keeps us from having to use another data structure. The
129 * node information is cleared just before we store the real mem_map.
130 */
131static inline unsigned long sparse_encode_early_nid(int nid)
132{
133 return (nid << SECTION_NID_SHIFT);
134}
135
136static inline int sparse_early_nid(struct mem_section *section)
137{
138 return (section->section_mem_map >> SECTION_NID_SHIFT);
139}
140
141/* Validate the physical addressing limitations of the model */
142void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
143 unsigned long *end_pfn)
144{
145 unsigned long max_sparsemem_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
146
147 /*
148 * Sanity checks - do not allow an architecture to pass
149 * in larger pfns than the maximum scope of sparsemem:
150 */
151 if (*start_pfn > max_sparsemem_pfn) {
152 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
153 "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
154 *start_pfn, *end_pfn, max_sparsemem_pfn);
155 WARN_ON_ONCE(1);
156 *start_pfn = max_sparsemem_pfn;
157 *end_pfn = max_sparsemem_pfn;
158 } else if (*end_pfn > max_sparsemem_pfn) {
159 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
160 "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
161 *start_pfn, *end_pfn, max_sparsemem_pfn);
162 WARN_ON_ONCE(1);
163 *end_pfn = max_sparsemem_pfn;
164 }
165}
166
167/*
168 * There are a number of times that we loop over NR_MEM_SECTIONS,
169 * looking for section_present() on each. But, when we have very
170 * large physical address spaces, NR_MEM_SECTIONS can also be
171 * very large which makes the loops quite long.
172 *
173 * Keeping track of this gives us an easy way to break out of
174 * those loops early.
175 */
176int __highest_present_section_nr;
177static void section_mark_present(struct mem_section *ms)
178{
179 int section_nr = __section_nr(ms);
180
181 if (section_nr > __highest_present_section_nr)
182 __highest_present_section_nr = section_nr;
183
184 ms->section_mem_map |= SECTION_MARKED_PRESENT;
185}
186
187static inline int next_present_section_nr(int section_nr)
188{
189 do {
190 section_nr++;
191 if (present_section_nr(section_nr))
192 return section_nr;
193 } while ((section_nr < NR_MEM_SECTIONS) &&
194 (section_nr <= __highest_present_section_nr));
195
196 return -1;
197}
198#define for_each_present_section_nr(start, section_nr) \
199 for (section_nr = next_present_section_nr(start-1); \
200 ((section_nr >= 0) && \
201 (section_nr < NR_MEM_SECTIONS) && \
202 (section_nr <= __highest_present_section_nr)); \
203 section_nr = next_present_section_nr(section_nr))
204
205/* Record a memory area against a node. */
206void __init memory_present(int nid, unsigned long start, unsigned long end)
207{
208 unsigned long pfn;
209
210#ifdef CONFIG_SPARSEMEM_EXTREME
211 if (unlikely(!mem_section)) {
212 unsigned long size, align;
213
214 size = sizeof(struct mem_section*) * NR_SECTION_ROOTS;
215 align = 1 << (INTERNODE_CACHE_SHIFT);
216 mem_section = memblock_virt_alloc(size, align);
217 }
218#endif
219
220 start &= PAGE_SECTION_MASK;
221 mminit_validate_memmodel_limits(&start, &end);
222 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
223 unsigned long section = pfn_to_section_nr(pfn);
224 struct mem_section *ms;
225
226 sparse_index_init(section, nid);
227 set_section_nid(section, nid);
228
229 ms = __nr_to_section(section);
230 if (!ms->section_mem_map) {
231 ms->section_mem_map = sparse_encode_early_nid(nid) |
232 SECTION_IS_ONLINE;
233 section_mark_present(ms);
234 }
235 }
236}
237
238/*
239 * Subtle, we encode the real pfn into the mem_map such that
240 * the identity pfn - section_mem_map will return the actual
241 * physical page frame number.
242 */
243static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
244{
245 unsigned long coded_mem_map =
246 (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
247 BUILD_BUG_ON(SECTION_MAP_LAST_BIT > (1UL<<PFN_SECTION_SHIFT));
248 BUG_ON(coded_mem_map & ~SECTION_MAP_MASK);
249 return coded_mem_map;
250}
251
252/*
253 * Decode mem_map from the coded memmap
254 */
255struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
256{
257 /* mask off the extra low bits of information */
258 coded_mem_map &= SECTION_MAP_MASK;
259 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
260}
261
262static int __meminit sparse_init_one_section(struct mem_section *ms,
263 unsigned long pnum, struct page *mem_map,
264 unsigned long *pageblock_bitmap)
265{
266 if (!present_section(ms))
267 return -EINVAL;
268
269 ms->section_mem_map &= ~SECTION_MAP_MASK;
270 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) |
271 SECTION_HAS_MEM_MAP;
272 ms->pageblock_flags = pageblock_bitmap;
273
274 return 1;
275}
276
277unsigned long usemap_size(void)
278{
279 return BITS_TO_LONGS(SECTION_BLOCKFLAGS_BITS) * sizeof(unsigned long);
280}
281
282#ifdef CONFIG_MEMORY_HOTPLUG
283static unsigned long *__kmalloc_section_usemap(void)
284{
285 return kmalloc(usemap_size(), GFP_KERNEL);
286}
287#endif /* CONFIG_MEMORY_HOTPLUG */
288
289#ifdef CONFIG_MEMORY_HOTREMOVE
290static unsigned long * __init
291sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
292 unsigned long size)
293{
294 unsigned long goal, limit;
295 unsigned long *p;
296 int nid;
297 /*
298 * A page may contain usemaps for other sections preventing the
299 * page being freed and making a section unremovable while
300 * other sections referencing the usemap remain active. Similarly,
301 * a pgdat can prevent a section being removed. If section A
302 * contains a pgdat and section B contains the usemap, both
303 * sections become inter-dependent. This allocates usemaps
304 * from the same section as the pgdat where possible to avoid
305 * this problem.
306 */
307 goal = __pa(pgdat) & (PAGE_SECTION_MASK << PAGE_SHIFT);
308 limit = goal + (1UL << PA_SECTION_SHIFT);
309 nid = early_pfn_to_nid(goal >> PAGE_SHIFT);
310again:
311 p = memblock_virt_alloc_try_nid_nopanic(size,
312 SMP_CACHE_BYTES, goal, limit,
313 nid);
314 if (!p && limit) {
315 limit = 0;
316 goto again;
317 }
318 return p;
319}
320
321static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
322{
323 unsigned long usemap_snr, pgdat_snr;
324 static unsigned long old_usemap_snr;
325 static unsigned long old_pgdat_snr;
326 struct pglist_data *pgdat = NODE_DATA(nid);
327 int usemap_nid;
328
329 /* First call */
330 if (!old_usemap_snr) {
331 old_usemap_snr = NR_MEM_SECTIONS;
332 old_pgdat_snr = NR_MEM_SECTIONS;
333 }
334
335 usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
336 pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
337 if (usemap_snr == pgdat_snr)
338 return;
339
340 if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
341 /* skip redundant message */
342 return;
343
344 old_usemap_snr = usemap_snr;
345 old_pgdat_snr = pgdat_snr;
346
347 usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
348 if (usemap_nid != nid) {
349 pr_info("node %d must be removed before remove section %ld\n",
350 nid, usemap_snr);
351 return;
352 }
353 /*
354 * There is a circular dependency.
355 * Some platforms allow un-removable section because they will just
356 * gather other removable sections for dynamic partitioning.
357 * Just notify un-removable section's number here.
358 */
359 pr_info("Section %ld and %ld (node %d) have a circular dependency on usemap and pgdat allocations\n",
360 usemap_snr, pgdat_snr, nid);
361}
362#else
363static unsigned long * __init
364sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
365 unsigned long size)
366{
367 return memblock_virt_alloc_node_nopanic(size, pgdat->node_id);
368}
369
370static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
371{
372}
373#endif /* CONFIG_MEMORY_HOTREMOVE */
374
375static void __init sparse_early_usemaps_alloc_node(void *data,
376 unsigned long pnum_begin,
377 unsigned long pnum_end,
378 unsigned long usemap_count, int nodeid)
379{
380 void *usemap;
381 unsigned long pnum;
382 unsigned long **usemap_map = (unsigned long **)data;
383 int size = usemap_size();
384
385 usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
386 size * usemap_count);
387 if (!usemap) {
388 pr_warn("%s: allocation failed\n", __func__);
389 return;
390 }
391
392 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
393 if (!present_section_nr(pnum))
394 continue;
395 usemap_map[pnum] = usemap;
396 usemap += size;
397 check_usemap_section_nr(nodeid, usemap_map[pnum]);
398 }
399}
400
401#ifndef CONFIG_SPARSEMEM_VMEMMAP
402struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid,
403 struct vmem_altmap *altmap)
404{
405 struct page *map;
406 unsigned long size;
407
408 size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
409 map = memblock_virt_alloc_try_nid(size,
410 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
411 BOOTMEM_ALLOC_ACCESSIBLE, nid);
412 return map;
413}
414void __init sparse_mem_maps_populate_node(struct page **map_map,
415 unsigned long pnum_begin,
416 unsigned long pnum_end,
417 unsigned long map_count, int nodeid)
418{
419 void *map;
420 unsigned long pnum;
421 unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
422
423 size = PAGE_ALIGN(size);
424 map = memblock_virt_alloc_try_nid_raw(size * map_count,
425 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
426 BOOTMEM_ALLOC_ACCESSIBLE, nodeid);
427 if (map) {
428 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
429 if (!present_section_nr(pnum))
430 continue;
431 map_map[pnum] = map;
432 map += size;
433 }
434 return;
435 }
436
437 /* fallback */
438 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
439 struct mem_section *ms;
440
441 if (!present_section_nr(pnum))
442 continue;
443 map_map[pnum] = sparse_mem_map_populate(pnum, nodeid, NULL);
444 if (map_map[pnum])
445 continue;
446 ms = __nr_to_section(pnum);
447 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
448 __func__);
449 ms->section_mem_map = 0;
450 }
451}
452#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
453
454#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
455static void __init sparse_early_mem_maps_alloc_node(void *data,
456 unsigned long pnum_begin,
457 unsigned long pnum_end,
458 unsigned long map_count, int nodeid)
459{
460 struct page **map_map = (struct page **)data;
461 sparse_mem_maps_populate_node(map_map, pnum_begin, pnum_end,
462 map_count, nodeid);
463}
464#else
465static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
466{
467 struct page *map;
468 struct mem_section *ms = __nr_to_section(pnum);
469 int nid = sparse_early_nid(ms);
470
471 map = sparse_mem_map_populate(pnum, nid, NULL);
472 if (map)
473 return map;
474
475 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
476 __func__);
477 ms->section_mem_map = 0;
478 return NULL;
479}
480#endif
481
482void __weak __meminit vmemmap_populate_print_last(void)
483{
484}
485
486/**
487 * alloc_usemap_and_memmap - memory alloction for pageblock flags and vmemmap
488 * @map: usemap_map for pageblock flags or mmap_map for vmemmap
489 */
490static void __init alloc_usemap_and_memmap(void (*alloc_func)
491 (void *, unsigned long, unsigned long,
492 unsigned long, int), void *data)
493{
494 unsigned long pnum;
495 unsigned long map_count;
496 int nodeid_begin = 0;
497 unsigned long pnum_begin = 0;
498
499 for_each_present_section_nr(0, pnum) {
500 struct mem_section *ms;
501
502 ms = __nr_to_section(pnum);
503 nodeid_begin = sparse_early_nid(ms);
504 pnum_begin = pnum;
505 break;
506 }
507 map_count = 1;
508 for_each_present_section_nr(pnum_begin + 1, pnum) {
509 struct mem_section *ms;
510 int nodeid;
511
512 ms = __nr_to_section(pnum);
513 nodeid = sparse_early_nid(ms);
514 if (nodeid == nodeid_begin) {
515 map_count++;
516 continue;
517 }
518 /* ok, we need to take cake of from pnum_begin to pnum - 1*/
519 alloc_func(data, pnum_begin, pnum,
520 map_count, nodeid_begin);
521 /* new start, update count etc*/
522 nodeid_begin = nodeid;
523 pnum_begin = pnum;
524 map_count = 1;
525 }
526 /* ok, last chunk */
527 alloc_func(data, pnum_begin, NR_MEM_SECTIONS,
528 map_count, nodeid_begin);
529}
530
531/*
532 * Allocate the accumulated non-linear sections, allocate a mem_map
533 * for each and record the physical to section mapping.
534 */
535void __init sparse_init(void)
536{
537 unsigned long pnum;
538 struct page *map;
539 unsigned long *usemap;
540 unsigned long **usemap_map;
541 int size;
542#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
543 int size2;
544 struct page **map_map;
545#endif
546
547 /* see include/linux/mmzone.h 'struct mem_section' definition */
548 BUILD_BUG_ON(!is_power_of_2(sizeof(struct mem_section)));
549
550 /* Setup pageblock_order for HUGETLB_PAGE_SIZE_VARIABLE */
551 set_pageblock_order();
552
553 /*
554 * map is using big page (aka 2M in x86 64 bit)
555 * usemap is less one page (aka 24 bytes)
556 * so alloc 2M (with 2M align) and 24 bytes in turn will
557 * make next 2M slip to one more 2M later.
558 * then in big system, the memory will have a lot of holes...
559 * here try to allocate 2M pages continuously.
560 *
561 * powerpc need to call sparse_init_one_section right after each
562 * sparse_early_mem_map_alloc, so allocate usemap_map at first.
563 */
564 size = sizeof(unsigned long *) * NR_MEM_SECTIONS;
565 usemap_map = memblock_virt_alloc(size, 0);
566 if (!usemap_map)
567 panic("can not allocate usemap_map\n");
568 alloc_usemap_and_memmap(sparse_early_usemaps_alloc_node,
569 (void *)usemap_map);
570
571#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
572 size2 = sizeof(struct page *) * NR_MEM_SECTIONS;
573 map_map = memblock_virt_alloc(size2, 0);
574 if (!map_map)
575 panic("can not allocate map_map\n");
576 alloc_usemap_and_memmap(sparse_early_mem_maps_alloc_node,
577 (void *)map_map);
578#endif
579
580 for_each_present_section_nr(0, pnum) {
581 usemap = usemap_map[pnum];
582 if (!usemap)
583 continue;
584
585#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
586 map = map_map[pnum];
587#else
588 map = sparse_early_mem_map_alloc(pnum);
589#endif
590 if (!map)
591 continue;
592
593 sparse_init_one_section(__nr_to_section(pnum), pnum, map,
594 usemap);
595 }
596
597 vmemmap_populate_print_last();
598
599#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
600 memblock_free_early(__pa(map_map), size2);
601#endif
602 memblock_free_early(__pa(usemap_map), size);
603}
604
605#ifdef CONFIG_MEMORY_HOTPLUG
606
607/* Mark all memory sections within the pfn range as online */
608void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
609{
610 unsigned long pfn;
611
612 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
613 unsigned long section_nr = pfn_to_section_nr(pfn);
614 struct mem_section *ms;
615
616 /* onlining code should never touch invalid ranges */
617 if (WARN_ON(!valid_section_nr(section_nr)))
618 continue;
619
620 ms = __nr_to_section(section_nr);
621 ms->section_mem_map |= SECTION_IS_ONLINE;
622 }
623}
624
625#ifdef CONFIG_MEMORY_HOTREMOVE
626/* Mark all memory sections within the pfn range as online */
627void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
628{
629 unsigned long pfn;
630
631 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
632 unsigned long section_nr = pfn_to_section_nr(pfn);
633 struct mem_section *ms;
634
635 /*
636 * TODO this needs some double checking. Offlining code makes
637 * sure to check pfn_valid but those checks might be just bogus
638 */
639 if (WARN_ON(!valid_section_nr(section_nr)))
640 continue;
641
642 ms = __nr_to_section(section_nr);
643 ms->section_mem_map &= ~SECTION_IS_ONLINE;
644 }
645}
646#endif
647
648#ifdef CONFIG_SPARSEMEM_VMEMMAP
649static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
650 struct vmem_altmap *altmap)
651{
652 /* This will make the necessary allocations eventually. */
653 return sparse_mem_map_populate(pnum, nid, altmap);
654}
655static void __kfree_section_memmap(struct page *memmap,
656 struct vmem_altmap *altmap)
657{
658 unsigned long start = (unsigned long)memmap;
659 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
660
661 vmemmap_free(start, end, altmap);
662}
663#ifdef CONFIG_MEMORY_HOTREMOVE
664static void free_map_bootmem(struct page *memmap)
665{
666 unsigned long start = (unsigned long)memmap;
667 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
668
669 vmemmap_free(start, end, NULL);
670}
671#endif /* CONFIG_MEMORY_HOTREMOVE */
672#else
673static struct page *__kmalloc_section_memmap(void)
674{
675 struct page *page, *ret;
676 unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION;
677
678 page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
679 if (page)
680 goto got_map_page;
681
682 ret = vmalloc(memmap_size);
683 if (ret)
684 goto got_map_ptr;
685
686 return NULL;
687got_map_page:
688 ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
689got_map_ptr:
690
691 return ret;
692}
693
694static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
695 struct vmem_altmap *altmap)
696{
697 return __kmalloc_section_memmap();
698}
699
700static void __kfree_section_memmap(struct page *memmap,
701 struct vmem_altmap *altmap)
702{
703 if (is_vmalloc_addr(memmap))
704 vfree(memmap);
705 else
706 free_pages((unsigned long)memmap,
707 get_order(sizeof(struct page) * PAGES_PER_SECTION));
708}
709
710#ifdef CONFIG_MEMORY_HOTREMOVE
711static void free_map_bootmem(struct page *memmap)
712{
713 unsigned long maps_section_nr, removing_section_nr, i;
714 unsigned long magic, nr_pages;
715 struct page *page = virt_to_page(memmap);
716
717 nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
718 >> PAGE_SHIFT;
719
720 for (i = 0; i < nr_pages; i++, page++) {
721 magic = (unsigned long) page->freelist;
722
723 BUG_ON(magic == NODE_INFO);
724
725 maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
726 removing_section_nr = page_private(page);
727
728 /*
729 * When this function is called, the removing section is
730 * logical offlined state. This means all pages are isolated
731 * from page allocator. If removing section's memmap is placed
732 * on the same section, it must not be freed.
733 * If it is freed, page allocator may allocate it which will
734 * be removed physically soon.
735 */
736 if (maps_section_nr != removing_section_nr)
737 put_page_bootmem(page);
738 }
739}
740#endif /* CONFIG_MEMORY_HOTREMOVE */
741#endif /* CONFIG_SPARSEMEM_VMEMMAP */
742
743/*
744 * returns the number of sections whose mem_maps were properly
745 * set. If this is <=0, then that means that the passed-in
746 * map was not consumed and must be freed.
747 */
748int __meminit sparse_add_one_section(struct pglist_data *pgdat,
749 unsigned long start_pfn, struct vmem_altmap *altmap)
750{
751 unsigned long section_nr = pfn_to_section_nr(start_pfn);
752 struct mem_section *ms;
753 struct page *memmap;
754 unsigned long *usemap;
755 unsigned long flags;
756 int ret;
757
758 /*
759 * no locking for this, because it does its own
760 * plus, it does a kmalloc
761 */
762 ret = sparse_index_init(section_nr, pgdat->node_id);
763 if (ret < 0 && ret != -EEXIST)
764 return ret;
765 memmap = kmalloc_section_memmap(section_nr, pgdat->node_id, altmap);
766 if (!memmap)
767 return -ENOMEM;
768 usemap = __kmalloc_section_usemap();
769 if (!usemap) {
770 __kfree_section_memmap(memmap, altmap);
771 return -ENOMEM;
772 }
773
774 pgdat_resize_lock(pgdat, &flags);
775
776 ms = __pfn_to_section(start_pfn);
777 if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
778 ret = -EEXIST;
779 goto out;
780 }
781
782#ifdef CONFIG_DEBUG_VM
783 /*
784 * Poison uninitialized struct pages in order to catch invalid flags
785 * combinations.
786 */
787 memset(memmap, PAGE_POISON_PATTERN, sizeof(struct page) * PAGES_PER_SECTION);
788#endif
789
790 section_mark_present(ms);
791
792 ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
793
794out:
795 pgdat_resize_unlock(pgdat, &flags);
796 if (ret <= 0) {
797 kfree(usemap);
798 __kfree_section_memmap(memmap, altmap);
799 }
800 return ret;
801}
802
803#ifdef CONFIG_MEMORY_HOTREMOVE
804#ifdef CONFIG_MEMORY_FAILURE
805static void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
806{
807 int i;
808
809 if (!memmap)
810 return;
811
812 for (i = 0; i < nr_pages; i++) {
813 if (PageHWPoison(&memmap[i])) {
814 atomic_long_sub(1, &num_poisoned_pages);
815 ClearPageHWPoison(&memmap[i]);
816 }
817 }
818}
819#else
820static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
821{
822}
823#endif
824
825static void free_section_usemap(struct page *memmap, unsigned long *usemap,
826 struct vmem_altmap *altmap)
827{
828 struct page *usemap_page;
829
830 if (!usemap)
831 return;
832
833 usemap_page = virt_to_page(usemap);
834 /*
835 * Check to see if allocation came from hot-plug-add
836 */
837 if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
838 kfree(usemap);
839 if (memmap)
840 __kfree_section_memmap(memmap, altmap);
841 return;
842 }
843
844 /*
845 * The usemap came from bootmem. This is packed with other usemaps
846 * on the section which has pgdat at boot time. Just keep it as is now.
847 */
848
849 if (memmap)
850 free_map_bootmem(memmap);
851}
852
853void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
854 unsigned long map_offset, struct vmem_altmap *altmap)
855{
856 struct page *memmap = NULL;
857 unsigned long *usemap = NULL, flags;
858 struct pglist_data *pgdat = zone->zone_pgdat;
859
860 pgdat_resize_lock(pgdat, &flags);
861 if (ms->section_mem_map) {
862 usemap = ms->pageblock_flags;
863 memmap = sparse_decode_mem_map(ms->section_mem_map,
864 __section_nr(ms));
865 ms->section_mem_map = 0;
866 ms->pageblock_flags = NULL;
867 }
868 pgdat_resize_unlock(pgdat, &flags);
869
870 clear_hwpoisoned_pages(memmap + map_offset,
871 PAGES_PER_SECTION - map_offset);
872 free_section_usemap(memmap, usemap, altmap);
873}
874#endif /* CONFIG_MEMORY_HOTREMOVE */
875#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 noinline struct mem_section __ref *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#ifdef CONFIG_SPARSEMEM_EXTREME
104int __section_nr(struct mem_section* ms)
105{
106 unsigned long root_nr;
107 struct mem_section* root;
108
109 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
110 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
111 if (!root)
112 continue;
113
114 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
115 break;
116 }
117
118 VM_BUG_ON(root_nr == NR_SECTION_ROOTS);
119
120 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
121}
122#else
123int __section_nr(struct mem_section* ms)
124{
125 return (int)(ms - mem_section[0]);
126}
127#endif
128
129/*
130 * During early boot, before section_mem_map is used for an actual
131 * mem_map, we use section_mem_map to store the section's NUMA
132 * node. This keeps us from having to use another data structure. The
133 * node information is cleared just before we store the real mem_map.
134 */
135static inline unsigned long sparse_encode_early_nid(int nid)
136{
137 return (nid << SECTION_NID_SHIFT);
138}
139
140static inline int sparse_early_nid(struct mem_section *section)
141{
142 return (section->section_mem_map >> SECTION_NID_SHIFT);
143}
144
145/* Validate the physical addressing limitations of the model */
146void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
147 unsigned long *end_pfn)
148{
149 unsigned long max_sparsemem_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
150
151 /*
152 * Sanity checks - do not allow an architecture to pass
153 * in larger pfns than the maximum scope of sparsemem:
154 */
155 if (*start_pfn > max_sparsemem_pfn) {
156 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
157 "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
158 *start_pfn, *end_pfn, max_sparsemem_pfn);
159 WARN_ON_ONCE(1);
160 *start_pfn = max_sparsemem_pfn;
161 *end_pfn = max_sparsemem_pfn;
162 } else if (*end_pfn > max_sparsemem_pfn) {
163 mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
164 "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
165 *start_pfn, *end_pfn, max_sparsemem_pfn);
166 WARN_ON_ONCE(1);
167 *end_pfn = max_sparsemem_pfn;
168 }
169}
170
171/* Record a memory area against a node. */
172void __init memory_present(int nid, unsigned long start, unsigned long end)
173{
174 unsigned long pfn;
175
176 start &= PAGE_SECTION_MASK;
177 mminit_validate_memmodel_limits(&start, &end);
178 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
179 unsigned long section = pfn_to_section_nr(pfn);
180 struct mem_section *ms;
181
182 sparse_index_init(section, nid);
183 set_section_nid(section, nid);
184
185 ms = __nr_to_section(section);
186 if (!ms->section_mem_map)
187 ms->section_mem_map = sparse_encode_early_nid(nid) |
188 SECTION_MARKED_PRESENT;
189 }
190}
191
192/*
193 * Only used by the i386 NUMA architecures, but relatively
194 * generic code.
195 */
196unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn,
197 unsigned long end_pfn)
198{
199 unsigned long pfn;
200 unsigned long nr_pages = 0;
201
202 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
203 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
204 if (nid != early_pfn_to_nid(pfn))
205 continue;
206
207 if (pfn_present(pfn))
208 nr_pages += PAGES_PER_SECTION;
209 }
210
211 return nr_pages * sizeof(struct page);
212}
213
214/*
215 * Subtle, we encode the real pfn into the mem_map such that
216 * the identity pfn - section_mem_map will return the actual
217 * physical page frame number.
218 */
219static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
220{
221 return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
222}
223
224/*
225 * Decode mem_map from the coded memmap
226 */
227struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
228{
229 /* mask off the extra low bits of information */
230 coded_mem_map &= SECTION_MAP_MASK;
231 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
232}
233
234static int __meminit sparse_init_one_section(struct mem_section *ms,
235 unsigned long pnum, struct page *mem_map,
236 unsigned long *pageblock_bitmap)
237{
238 if (!present_section(ms))
239 return -EINVAL;
240
241 ms->section_mem_map &= ~SECTION_MAP_MASK;
242 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) |
243 SECTION_HAS_MEM_MAP;
244 ms->pageblock_flags = pageblock_bitmap;
245
246 return 1;
247}
248
249unsigned long usemap_size(void)
250{
251 unsigned long size_bytes;
252 size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
253 size_bytes = roundup(size_bytes, sizeof(unsigned long));
254 return size_bytes;
255}
256
257#ifdef CONFIG_MEMORY_HOTPLUG
258static unsigned long *__kmalloc_section_usemap(void)
259{
260 return kmalloc(usemap_size(), GFP_KERNEL);
261}
262#endif /* CONFIG_MEMORY_HOTPLUG */
263
264#ifdef CONFIG_MEMORY_HOTREMOVE
265static unsigned long * __init
266sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
267 unsigned long size)
268{
269 unsigned long goal, limit;
270 unsigned long *p;
271 int nid;
272 /*
273 * A page may contain usemaps for other sections preventing the
274 * page being freed and making a section unremovable while
275 * other sections referencing the usemap remain active. Similarly,
276 * a pgdat can prevent a section being removed. If section A
277 * contains a pgdat and section B contains the usemap, both
278 * sections become inter-dependent. This allocates usemaps
279 * from the same section as the pgdat where possible to avoid
280 * this problem.
281 */
282 goal = __pa(pgdat) & (PAGE_SECTION_MASK << PAGE_SHIFT);
283 limit = goal + (1UL << PA_SECTION_SHIFT);
284 nid = early_pfn_to_nid(goal >> PAGE_SHIFT);
285again:
286 p = memblock_virt_alloc_try_nid_nopanic(size,
287 SMP_CACHE_BYTES, goal, limit,
288 nid);
289 if (!p && limit) {
290 limit = 0;
291 goto again;
292 }
293 return p;
294}
295
296static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
297{
298 unsigned long usemap_snr, pgdat_snr;
299 static unsigned long old_usemap_snr = NR_MEM_SECTIONS;
300 static unsigned long old_pgdat_snr = NR_MEM_SECTIONS;
301 struct pglist_data *pgdat = NODE_DATA(nid);
302 int usemap_nid;
303
304 usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
305 pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
306 if (usemap_snr == pgdat_snr)
307 return;
308
309 if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
310 /* skip redundant message */
311 return;
312
313 old_usemap_snr = usemap_snr;
314 old_pgdat_snr = pgdat_snr;
315
316 usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
317 if (usemap_nid != nid) {
318 pr_info("node %d must be removed before remove section %ld\n",
319 nid, usemap_snr);
320 return;
321 }
322 /*
323 * There is a circular dependency.
324 * Some platforms allow un-removable section because they will just
325 * gather other removable sections for dynamic partitioning.
326 * Just notify un-removable section's number here.
327 */
328 pr_info("Section %ld and %ld (node %d) have a circular dependency on usemap and pgdat allocations\n",
329 usemap_snr, pgdat_snr, nid);
330}
331#else
332static unsigned long * __init
333sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
334 unsigned long size)
335{
336 return memblock_virt_alloc_node_nopanic(size, pgdat->node_id);
337}
338
339static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
340{
341}
342#endif /* CONFIG_MEMORY_HOTREMOVE */
343
344static void __init sparse_early_usemaps_alloc_node(void *data,
345 unsigned long pnum_begin,
346 unsigned long pnum_end,
347 unsigned long usemap_count, int nodeid)
348{
349 void *usemap;
350 unsigned long pnum;
351 unsigned long **usemap_map = (unsigned long **)data;
352 int size = usemap_size();
353
354 usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
355 size * usemap_count);
356 if (!usemap) {
357 pr_warn("%s: allocation failed\n", __func__);
358 return;
359 }
360
361 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
362 if (!present_section_nr(pnum))
363 continue;
364 usemap_map[pnum] = usemap;
365 usemap += size;
366 check_usemap_section_nr(nodeid, usemap_map[pnum]);
367 }
368}
369
370#ifndef CONFIG_SPARSEMEM_VMEMMAP
371struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
372{
373 struct page *map;
374 unsigned long size;
375
376 map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
377 if (map)
378 return map;
379
380 size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
381 map = memblock_virt_alloc_try_nid(size,
382 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
383 BOOTMEM_ALLOC_ACCESSIBLE, nid);
384 return map;
385}
386void __init sparse_mem_maps_populate_node(struct page **map_map,
387 unsigned long pnum_begin,
388 unsigned long pnum_end,
389 unsigned long map_count, int nodeid)
390{
391 void *map;
392 unsigned long pnum;
393 unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
394
395 map = alloc_remap(nodeid, size * map_count);
396 if (map) {
397 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
398 if (!present_section_nr(pnum))
399 continue;
400 map_map[pnum] = map;
401 map += size;
402 }
403 return;
404 }
405
406 size = PAGE_ALIGN(size);
407 map = memblock_virt_alloc_try_nid(size * map_count,
408 PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
409 BOOTMEM_ALLOC_ACCESSIBLE, nodeid);
410 if (map) {
411 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
412 if (!present_section_nr(pnum))
413 continue;
414 map_map[pnum] = map;
415 map += size;
416 }
417 return;
418 }
419
420 /* fallback */
421 for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
422 struct mem_section *ms;
423
424 if (!present_section_nr(pnum))
425 continue;
426 map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
427 if (map_map[pnum])
428 continue;
429 ms = __nr_to_section(pnum);
430 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
431 __func__);
432 ms->section_mem_map = 0;
433 }
434}
435#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
436
437#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
438static void __init sparse_early_mem_maps_alloc_node(void *data,
439 unsigned long pnum_begin,
440 unsigned long pnum_end,
441 unsigned long map_count, int nodeid)
442{
443 struct page **map_map = (struct page **)data;
444 sparse_mem_maps_populate_node(map_map, pnum_begin, pnum_end,
445 map_count, nodeid);
446}
447#else
448static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
449{
450 struct page *map;
451 struct mem_section *ms = __nr_to_section(pnum);
452 int nid = sparse_early_nid(ms);
453
454 map = sparse_mem_map_populate(pnum, nid);
455 if (map)
456 return map;
457
458 pr_err("%s: sparsemem memory map backing failed some memory will not be available\n",
459 __func__);
460 ms->section_mem_map = 0;
461 return NULL;
462}
463#endif
464
465void __weak __meminit vmemmap_populate_print_last(void)
466{
467}
468
469/**
470 * alloc_usemap_and_memmap - memory alloction for pageblock flags and vmemmap
471 * @map: usemap_map for pageblock flags or mmap_map for vmemmap
472 */
473static void __init alloc_usemap_and_memmap(void (*alloc_func)
474 (void *, unsigned long, unsigned long,
475 unsigned long, int), void *data)
476{
477 unsigned long pnum;
478 unsigned long map_count;
479 int nodeid_begin = 0;
480 unsigned long pnum_begin = 0;
481
482 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
483 struct mem_section *ms;
484
485 if (!present_section_nr(pnum))
486 continue;
487 ms = __nr_to_section(pnum);
488 nodeid_begin = sparse_early_nid(ms);
489 pnum_begin = pnum;
490 break;
491 }
492 map_count = 1;
493 for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
494 struct mem_section *ms;
495 int nodeid;
496
497 if (!present_section_nr(pnum))
498 continue;
499 ms = __nr_to_section(pnum);
500 nodeid = sparse_early_nid(ms);
501 if (nodeid == nodeid_begin) {
502 map_count++;
503 continue;
504 }
505 /* ok, we need to take cake of from pnum_begin to pnum - 1*/
506 alloc_func(data, pnum_begin, pnum,
507 map_count, nodeid_begin);
508 /* new start, update count etc*/
509 nodeid_begin = nodeid;
510 pnum_begin = pnum;
511 map_count = 1;
512 }
513 /* ok, last chunk */
514 alloc_func(data, pnum_begin, NR_MEM_SECTIONS,
515 map_count, nodeid_begin);
516}
517
518/*
519 * Allocate the accumulated non-linear sections, allocate a mem_map
520 * for each and record the physical to section mapping.
521 */
522void __init sparse_init(void)
523{
524 unsigned long pnum;
525 struct page *map;
526 unsigned long *usemap;
527 unsigned long **usemap_map;
528 int size;
529#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
530 int size2;
531 struct page **map_map;
532#endif
533
534 /* see include/linux/mmzone.h 'struct mem_section' definition */
535 BUILD_BUG_ON(!is_power_of_2(sizeof(struct mem_section)));
536
537 /* Setup pageblock_order for HUGETLB_PAGE_SIZE_VARIABLE */
538 set_pageblock_order();
539
540 /*
541 * map is using big page (aka 2M in x86 64 bit)
542 * usemap is less one page (aka 24 bytes)
543 * so alloc 2M (with 2M align) and 24 bytes in turn will
544 * make next 2M slip to one more 2M later.
545 * then in big system, the memory will have a lot of holes...
546 * here try to allocate 2M pages continuously.
547 *
548 * powerpc need to call sparse_init_one_section right after each
549 * sparse_early_mem_map_alloc, so allocate usemap_map at first.
550 */
551 size = sizeof(unsigned long *) * NR_MEM_SECTIONS;
552 usemap_map = memblock_virt_alloc(size, 0);
553 if (!usemap_map)
554 panic("can not allocate usemap_map\n");
555 alloc_usemap_and_memmap(sparse_early_usemaps_alloc_node,
556 (void *)usemap_map);
557
558#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
559 size2 = sizeof(struct page *) * NR_MEM_SECTIONS;
560 map_map = memblock_virt_alloc(size2, 0);
561 if (!map_map)
562 panic("can not allocate map_map\n");
563 alloc_usemap_and_memmap(sparse_early_mem_maps_alloc_node,
564 (void *)map_map);
565#endif
566
567 for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
568 if (!present_section_nr(pnum))
569 continue;
570
571 usemap = usemap_map[pnum];
572 if (!usemap)
573 continue;
574
575#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
576 map = map_map[pnum];
577#else
578 map = sparse_early_mem_map_alloc(pnum);
579#endif
580 if (!map)
581 continue;
582
583 sparse_init_one_section(__nr_to_section(pnum), pnum, map,
584 usemap);
585 }
586
587 vmemmap_populate_print_last();
588
589#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
590 memblock_free_early(__pa(map_map), size2);
591#endif
592 memblock_free_early(__pa(usemap_map), size);
593}
594
595#ifdef CONFIG_MEMORY_HOTPLUG
596#ifdef CONFIG_SPARSEMEM_VMEMMAP
597static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
598{
599 /* This will make the necessary allocations eventually. */
600 return sparse_mem_map_populate(pnum, nid);
601}
602static void __kfree_section_memmap(struct page *memmap)
603{
604 unsigned long start = (unsigned long)memmap;
605 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
606
607 vmemmap_free(start, end);
608}
609#ifdef CONFIG_MEMORY_HOTREMOVE
610static void free_map_bootmem(struct page *memmap)
611{
612 unsigned long start = (unsigned long)memmap;
613 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
614
615 vmemmap_free(start, end);
616}
617#endif /* CONFIG_MEMORY_HOTREMOVE */
618#else
619static struct page *__kmalloc_section_memmap(void)
620{
621 struct page *page, *ret;
622 unsigned long memmap_size = sizeof(struct page) * PAGES_PER_SECTION;
623
624 page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
625 if (page)
626 goto got_map_page;
627
628 ret = vmalloc(memmap_size);
629 if (ret)
630 goto got_map_ptr;
631
632 return NULL;
633got_map_page:
634 ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
635got_map_ptr:
636
637 return ret;
638}
639
640static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid)
641{
642 return __kmalloc_section_memmap();
643}
644
645static void __kfree_section_memmap(struct page *memmap)
646{
647 if (is_vmalloc_addr(memmap))
648 vfree(memmap);
649 else
650 free_pages((unsigned long)memmap,
651 get_order(sizeof(struct page) * PAGES_PER_SECTION));
652}
653
654#ifdef CONFIG_MEMORY_HOTREMOVE
655static void free_map_bootmem(struct page *memmap)
656{
657 unsigned long maps_section_nr, removing_section_nr, i;
658 unsigned long magic, nr_pages;
659 struct page *page = virt_to_page(memmap);
660
661 nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
662 >> PAGE_SHIFT;
663
664 for (i = 0; i < nr_pages; i++, page++) {
665 magic = (unsigned long) page->lru.next;
666
667 BUG_ON(magic == NODE_INFO);
668
669 maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
670 removing_section_nr = page->private;
671
672 /*
673 * When this function is called, the removing section is
674 * logical offlined state. This means all pages are isolated
675 * from page allocator. If removing section's memmap is placed
676 * on the same section, it must not be freed.
677 * If it is freed, page allocator may allocate it which will
678 * be removed physically soon.
679 */
680 if (maps_section_nr != removing_section_nr)
681 put_page_bootmem(page);
682 }
683}
684#endif /* CONFIG_MEMORY_HOTREMOVE */
685#endif /* CONFIG_SPARSEMEM_VMEMMAP */
686
687/*
688 * returns the number of sections whose mem_maps were properly
689 * set. If this is <=0, then that means that the passed-in
690 * map was not consumed and must be freed.
691 */
692int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn)
693{
694 unsigned long section_nr = pfn_to_section_nr(start_pfn);
695 struct pglist_data *pgdat = zone->zone_pgdat;
696 struct mem_section *ms;
697 struct page *memmap;
698 unsigned long *usemap;
699 unsigned long flags;
700 int ret;
701
702 /*
703 * no locking for this, because it does its own
704 * plus, it does a kmalloc
705 */
706 ret = sparse_index_init(section_nr, pgdat->node_id);
707 if (ret < 0 && ret != -EEXIST)
708 return ret;
709 memmap = kmalloc_section_memmap(section_nr, pgdat->node_id);
710 if (!memmap)
711 return -ENOMEM;
712 usemap = __kmalloc_section_usemap();
713 if (!usemap) {
714 __kfree_section_memmap(memmap);
715 return -ENOMEM;
716 }
717
718 pgdat_resize_lock(pgdat, &flags);
719
720 ms = __pfn_to_section(start_pfn);
721 if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
722 ret = -EEXIST;
723 goto out;
724 }
725
726 memset(memmap, 0, sizeof(struct page) * PAGES_PER_SECTION);
727
728 ms->section_mem_map |= SECTION_MARKED_PRESENT;
729
730 ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
731
732out:
733 pgdat_resize_unlock(pgdat, &flags);
734 if (ret <= 0) {
735 kfree(usemap);
736 __kfree_section_memmap(memmap);
737 }
738 return ret;
739}
740
741#ifdef CONFIG_MEMORY_HOTREMOVE
742#ifdef CONFIG_MEMORY_FAILURE
743static void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
744{
745 int i;
746
747 if (!memmap)
748 return;
749
750 for (i = 0; i < nr_pages; i++) {
751 if (PageHWPoison(&memmap[i])) {
752 atomic_long_sub(1, &num_poisoned_pages);
753 ClearPageHWPoison(&memmap[i]);
754 }
755 }
756}
757#else
758static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
759{
760}
761#endif
762
763static void free_section_usemap(struct page *memmap, unsigned long *usemap)
764{
765 struct page *usemap_page;
766
767 if (!usemap)
768 return;
769
770 usemap_page = virt_to_page(usemap);
771 /*
772 * Check to see if allocation came from hot-plug-add
773 */
774 if (PageSlab(usemap_page) || PageCompound(usemap_page)) {
775 kfree(usemap);
776 if (memmap)
777 __kfree_section_memmap(memmap);
778 return;
779 }
780
781 /*
782 * The usemap came from bootmem. This is packed with other usemaps
783 * on the section which has pgdat at boot time. Just keep it as is now.
784 */
785
786 if (memmap)
787 free_map_bootmem(memmap);
788}
789
790void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
791 unsigned long map_offset)
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 + map_offset,
808 PAGES_PER_SECTION - map_offset);
809 free_section_usemap(memmap, usemap);
810}
811#endif /* CONFIG_MEMORY_HOTREMOVE */
812#endif /* CONFIG_MEMORY_HOTPLUG */