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