1
2
3
4
5#include <linux/mm.h>
6#include <linux/slab.h>
7#include <linux/mmzone.h>
8#include <linux/memblock.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#include <linux/swap.h>
15#include <linux/swapops.h>
16#include <linux/bootmem_info.h>
17
18#include "internal.h"
19#include <asm/dma.h>
20
21
22
23
24
25
26#ifdef CONFIG_SPARSEMEM_EXTREME
27struct mem_section **mem_section;
28#else
29struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
30 ____cacheline_internodealigned_in_smp;
31#endif
32EXPORT_SYMBOL(mem_section);
33
34#ifdef NODE_NOT_IN_PAGE_FLAGS
35
36
37
38
39
40#if MAX_NUMNODES <= 256
41static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
42#else
43static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
44#endif
45
46int page_to_nid(const struct page *page)
47{
48 return section_to_node_table[page_to_section(page)];
49}
50EXPORT_SYMBOL(page_to_nid);
51
52static void set_section_nid(unsigned long section_nr, int nid)
53{
54 section_to_node_table[section_nr] = nid;
55}
56#else
57static inline void set_section_nid(unsigned long section_nr, int nid)
58{
59}
60#endif
61
62#ifdef CONFIG_SPARSEMEM_EXTREME
63static noinline struct mem_section __ref *sparse_index_alloc(int nid)
64{
65 struct mem_section *section = NULL;
66 unsigned long array_size = SECTIONS_PER_ROOT *
67 sizeof(struct mem_section);
68
69 if (slab_is_available()) {
70 section = kzalloc_node(array_size, GFP_KERNEL, nid);
71 } else {
72 section = memblock_alloc_node(array_size, SMP_CACHE_BYTES,
73 nid);
74 if (!section)
75 panic("%s: Failed to allocate %lu bytes nid=%d\n",
76 __func__, array_size, nid);
77 }
78
79 return section;
80}
81
82static int __meminit sparse_index_init(unsigned long section_nr, int nid)
83{
84 unsigned long root = SECTION_NR_TO_ROOT(section_nr);
85 struct mem_section *section;
86
87
88
89
90
91
92
93
94 if (mem_section[root])
95 return 0;
96
97 section = sparse_index_alloc(nid);
98 if (!section)
99 return -ENOMEM;
100
101 mem_section[root] = section;
102
103 return 0;
104}
105#else
106static inline int sparse_index_init(unsigned long section_nr, int nid)
107{
108 return 0;
109}
110#endif
111
112#ifdef CONFIG_SPARSEMEM_EXTREME
113unsigned long __section_nr(struct mem_section *ms)
114{
115 unsigned long root_nr;
116 struct mem_section *root = NULL;
117
118 for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
119 root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
120 if (!root)
121 continue;
122
123 if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
124 break;
125 }
126
127 VM_BUG_ON(!root);
128
129 return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
130}
131#else
132unsigned long __section_nr(struct mem_section *ms)
133{
134 return (unsigned long)(ms - mem_section[0]);
135}
136#endif
137
138
139
140
141
142
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
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
162
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
181
182
183
184
185
186
187
188
189unsigned long __highest_present_section_nr;
190static void section_mark_present(struct mem_section *ms)
191{
192 unsigned long section_nr = __section_nr(ms);
193
194 if (section_nr > __highest_present_section_nr)
195 __highest_present_section_nr = section_nr;
196
197 ms->section_mem_map |= SECTION_MARKED_PRESENT;
198}
199
200#define for_each_present_section_nr(start, section_nr) \
201 for (section_nr = next_present_section_nr(start-1); \
202 ((section_nr != -1) && \
203 (section_nr <= __highest_present_section_nr)); \
204 section_nr = next_present_section_nr(section_nr))
205
206static inline unsigned long first_present_section_nr(void)
207{
208 return next_present_section_nr(-1);
209}
210
211#ifdef CONFIG_SPARSEMEM_VMEMMAP
212static void subsection_mask_set(unsigned long *map, unsigned long pfn,
213 unsigned long nr_pages)
214{
215 int idx = subsection_map_index(pfn);
216 int end = subsection_map_index(pfn + nr_pages - 1);
217
218 bitmap_set(map, idx, end - idx + 1);
219}
220
221void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages)
222{
223 int end_sec = pfn_to_section_nr(pfn + nr_pages - 1);
224 unsigned long nr, start_sec = pfn_to_section_nr(pfn);
225
226 if (!nr_pages)
227 return;
228
229 for (nr = start_sec; nr <= end_sec; nr++) {
230 struct mem_section *ms;
231 unsigned long pfns;
232
233 pfns = min(nr_pages, PAGES_PER_SECTION
234 - (pfn & ~PAGE_SECTION_MASK));
235 ms = __nr_to_section(nr);
236 subsection_mask_set(ms->usage->subsection_map, pfn, pfns);
237
238 pr_debug("%s: sec: %lu pfns: %lu set(%d, %d)\n", __func__, nr,
239 pfns, subsection_map_index(pfn),
240 subsection_map_index(pfn + pfns - 1));
241
242 pfn += pfns;
243 nr_pages -= pfns;
244 }
245}
246#else
247void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages)
248{
249}
250#endif
251
252
253static void __init memory_present(int nid, unsigned long start, unsigned long end)
254{
255 unsigned long pfn;
256
257#ifdef CONFIG_SPARSEMEM_EXTREME
258 if (unlikely(!mem_section)) {
259 unsigned long size, align;
260
261 size = sizeof(struct mem_section *) * NR_SECTION_ROOTS;
262 align = 1 << (INTERNODE_CACHE_SHIFT);
263 mem_section = memblock_alloc(size, align);
264 if (!mem_section)
265 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
266 __func__, size, align);
267 }
268#endif
269
270 start &= PAGE_SECTION_MASK;
271 mminit_validate_memmodel_limits(&start, &end);
272 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
273 unsigned long section = pfn_to_section_nr(pfn);
274 struct mem_section *ms;
275
276 sparse_index_init(section, nid);
277 set_section_nid(section, nid);
278
279 ms = __nr_to_section(section);
280 if (!ms->section_mem_map) {
281 ms->section_mem_map = sparse_encode_early_nid(nid) |
282 SECTION_IS_ONLINE;
283 section_mark_present(ms);
284 }
285 }
286}
287
288
289
290
291
292
293static void __init memblocks_present(void)
294{
295 unsigned long start, end;
296 int i, nid;
297
298 for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid)
299 memory_present(nid, start, end);
300}
301
302
303
304
305
306
307static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
308{
309 unsigned long coded_mem_map =
310 (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
311 BUILD_BUG_ON(SECTION_MAP_LAST_BIT > (1UL<<PFN_SECTION_SHIFT));
312 BUG_ON(coded_mem_map & ~SECTION_MAP_MASK);
313 return coded_mem_map;
314}
315
316#ifdef CONFIG_MEMORY_HOTPLUG
317
318
319
320struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
321{
322
323 coded_mem_map &= SECTION_MAP_MASK;
324 return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
325}
326#endif
327
328static void __meminit sparse_init_one_section(struct mem_section *ms,
329 unsigned long pnum, struct page *mem_map,
330 struct mem_section_usage *usage, unsigned long flags)
331{
332 ms->section_mem_map &= ~SECTION_MAP_MASK;
333 ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum)
334 | SECTION_HAS_MEM_MAP | flags;
335 ms->usage = usage;
336}
337
338static unsigned long usemap_size(void)
339{
340 return BITS_TO_LONGS(SECTION_BLOCKFLAGS_BITS) * sizeof(unsigned long);
341}
342
343size_t mem_section_usage_size(void)
344{
345 return sizeof(struct mem_section_usage) + usemap_size();
346}
347
348static inline phys_addr_t pgdat_to_phys(struct pglist_data *pgdat)
349{
350#ifndef CONFIG_NUMA
351 return __pa_symbol(pgdat);
352#else
353 return __pa(pgdat);
354#endif
355}
356
357#ifdef CONFIG_MEMORY_HOTREMOVE
358static struct mem_section_usage * __init
359sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
360 unsigned long size)
361{
362 struct mem_section_usage *usage;
363 unsigned long goal, limit;
364 int nid;
365
366
367
368
369
370
371
372
373
374
375 goal = pgdat_to_phys(pgdat) & (PAGE_SECTION_MASK << PAGE_SHIFT);
376 limit = goal + (1UL << PA_SECTION_SHIFT);
377 nid = early_pfn_to_nid(goal >> PAGE_SHIFT);
378again:
379 usage = memblock_alloc_try_nid(size, SMP_CACHE_BYTES, goal, limit, nid);
380 if (!usage && limit) {
381 limit = 0;
382 goto again;
383 }
384 return usage;
385}
386
387static void __init check_usemap_section_nr(int nid,
388 struct mem_section_usage *usage)
389{
390 unsigned long usemap_snr, pgdat_snr;
391 static unsigned long old_usemap_snr;
392 static unsigned long old_pgdat_snr;
393 struct pglist_data *pgdat = NODE_DATA(nid);
394 int usemap_nid;
395
396
397 if (!old_usemap_snr) {
398 old_usemap_snr = NR_MEM_SECTIONS;
399 old_pgdat_snr = NR_MEM_SECTIONS;
400 }
401
402 usemap_snr = pfn_to_section_nr(__pa(usage) >> PAGE_SHIFT);
403 pgdat_snr = pfn_to_section_nr(pgdat_to_phys(pgdat) >> PAGE_SHIFT);
404 if (usemap_snr == pgdat_snr)
405 return;
406
407 if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
408
409 return;
410
411 old_usemap_snr = usemap_snr;
412 old_pgdat_snr = pgdat_snr;
413
414 usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
415 if (usemap_nid != nid) {
416 pr_info("node %d must be removed before remove section %ld\n",
417 nid, usemap_snr);
418 return;
419 }
420
421
422
423
424
425
426 pr_info("Section %ld and %ld (node %d) have a circular dependency on usemap and pgdat allocations\n",
427 usemap_snr, pgdat_snr, nid);
428}
429#else
430static struct mem_section_usage * __init
431sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
432 unsigned long size)
433{
434 return memblock_alloc_node(size, SMP_CACHE_BYTES, pgdat->node_id);
435}
436
437static void __init check_usemap_section_nr(int nid,
438 struct mem_section_usage *usage)
439{
440}
441#endif
442
443#ifdef CONFIG_SPARSEMEM_VMEMMAP
444static unsigned long __init section_map_size(void)
445{
446 return ALIGN(sizeof(struct page) * PAGES_PER_SECTION, PMD_SIZE);
447}
448
449#else
450static unsigned long __init section_map_size(void)
451{
452 return PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
453}
454
455struct page __init *__populate_section_memmap(unsigned long pfn,
456 unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
457{
458 unsigned long size = section_map_size();
459 struct page *map = sparse_buffer_alloc(size);
460 phys_addr_t addr = __pa(MAX_DMA_ADDRESS);
461
462 if (map)
463 return map;
464
465 map = memblock_alloc_try_nid_raw(size, size, addr,
466 MEMBLOCK_ALLOC_ACCESSIBLE, nid);
467 if (!map)
468 panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d from=%pa\n",
469 __func__, size, PAGE_SIZE, nid, &addr);
470
471 return map;
472}
473#endif
474
475static void *sparsemap_buf __meminitdata;
476static void *sparsemap_buf_end __meminitdata;
477
478static inline void __meminit sparse_buffer_free(unsigned long size)
479{
480 WARN_ON(!sparsemap_buf || size == 0);
481 memblock_free_early(__pa(sparsemap_buf), size);
482}
483
484static void __init sparse_buffer_init(unsigned long size, int nid)
485{
486 phys_addr_t addr = __pa(MAX_DMA_ADDRESS);
487 WARN_ON(sparsemap_buf);
488
489
490
491
492
493 sparsemap_buf = memblock_alloc_exact_nid_raw(size, section_map_size(),
494 addr, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
495 sparsemap_buf_end = sparsemap_buf + size;
496}
497
498static void __init sparse_buffer_fini(void)
499{
500 unsigned long size = sparsemap_buf_end - sparsemap_buf;
501
502 if (sparsemap_buf && size > 0)
503 sparse_buffer_free(size);
504 sparsemap_buf = NULL;
505}
506
507void * __meminit sparse_buffer_alloc(unsigned long size)
508{
509 void *ptr = NULL;
510
511 if (sparsemap_buf) {
512 ptr = (void *) roundup((unsigned long)sparsemap_buf, size);
513 if (ptr + size > sparsemap_buf_end)
514 ptr = NULL;
515 else {
516
517 if ((unsigned long)(ptr - sparsemap_buf) > 0)
518 sparse_buffer_free((unsigned long)(ptr - sparsemap_buf));
519 sparsemap_buf = ptr + size;
520 }
521 }
522 return ptr;
523}
524
525void __weak __meminit vmemmap_populate_print_last(void)
526{
527}
528
529
530
531
532
533static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
534 unsigned long pnum_end,
535 unsigned long map_count)
536{
537 struct mem_section_usage *usage;
538 unsigned long pnum;
539 struct page *map;
540
541 usage = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nid),
542 mem_section_usage_size() * map_count);
543 if (!usage) {
544 pr_err("%s: node[%d] usemap allocation failed", __func__, nid);
545 goto failed;
546 }
547 sparse_buffer_init(map_count * section_map_size(), nid);
548 for_each_present_section_nr(pnum_begin, pnum) {
549 unsigned long pfn = section_nr_to_pfn(pnum);
550
551 if (pnum >= pnum_end)
552 break;
553
554 map = __populate_section_memmap(pfn, PAGES_PER_SECTION,
555 nid, NULL);
556 if (!map) {
557 pr_err("%s: node[%d] memory map backing failed. Some memory will not be available.",
558 __func__, nid);
559 pnum_begin = pnum;
560 sparse_buffer_fini();
561 goto failed;
562 }
563 check_usemap_section_nr(nid, usage);
564 sparse_init_one_section(__nr_to_section(pnum), pnum, map, usage,
565 SECTION_IS_EARLY);
566 usage = (void *) usage + mem_section_usage_size();
567 }
568 sparse_buffer_fini();
569 return;
570failed:
571
572 for_each_present_section_nr(pnum_begin, pnum) {
573 struct mem_section *ms;
574
575 if (pnum >= pnum_end)
576 break;
577 ms = __nr_to_section(pnum);
578 ms->section_mem_map = 0;
579 }
580}
581
582
583
584
585
586void __init sparse_init(void)
587{
588 unsigned long pnum_end, pnum_begin, map_count = 1;
589 int nid_begin;
590
591 memblocks_present();
592
593 pnum_begin = first_present_section_nr();
594 nid_begin = sparse_early_nid(__nr_to_section(pnum_begin));
595
596
597 set_pageblock_order();
598
599 for_each_present_section_nr(pnum_begin + 1, pnum_end) {
600 int nid = sparse_early_nid(__nr_to_section(pnum_end));
601
602 if (nid == nid_begin) {
603 map_count++;
604 continue;
605 }
606
607 sparse_init_nid(nid_begin, pnum_begin, pnum_end, map_count);
608 nid_begin = nid;
609 pnum_begin = pnum_end;
610 map_count = 1;
611 }
612
613 sparse_init_nid(nid_begin, pnum_begin, pnum_end, map_count);
614 vmemmap_populate_print_last();
615}
616
617#ifdef CONFIG_MEMORY_HOTPLUG
618
619
620void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
621{
622 unsigned long pfn;
623
624 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
625 unsigned long section_nr = pfn_to_section_nr(pfn);
626 struct mem_section *ms;
627
628
629 if (WARN_ON(!valid_section_nr(section_nr)))
630 continue;
631
632 ms = __nr_to_section(section_nr);
633 ms->section_mem_map |= SECTION_IS_ONLINE;
634 }
635}
636
637
638void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
639{
640 unsigned long pfn;
641
642 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
643 unsigned long section_nr = pfn_to_section_nr(pfn);
644 struct mem_section *ms;
645
646
647
648
649
650 if (WARN_ON(!valid_section_nr(section_nr)))
651 continue;
652
653 ms = __nr_to_section(section_nr);
654 ms->section_mem_map &= ~SECTION_IS_ONLINE;
655 }
656}
657
658#ifdef CONFIG_SPARSEMEM_VMEMMAP
659static struct page * __meminit populate_section_memmap(unsigned long pfn,
660 unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
661{
662 return __populate_section_memmap(pfn, nr_pages, nid, altmap);
663}
664
665static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages,
666 struct vmem_altmap *altmap)
667{
668 unsigned long start = (unsigned long) pfn_to_page(pfn);
669 unsigned long end = start + nr_pages * sizeof(struct page);
670
671 vmemmap_free(start, end, altmap);
672}
673static void free_map_bootmem(struct page *memmap)
674{
675 unsigned long start = (unsigned long)memmap;
676 unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
677
678 vmemmap_free(start, end, NULL);
679}
680
681static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
682{
683 DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
684 DECLARE_BITMAP(tmp, SUBSECTIONS_PER_SECTION) = { 0 };
685 struct mem_section *ms = __pfn_to_section(pfn);
686 unsigned long *subsection_map = ms->usage
687 ? &ms->usage->subsection_map[0] : NULL;
688
689 subsection_mask_set(map, pfn, nr_pages);
690 if (subsection_map)
691 bitmap_and(tmp, map, subsection_map, SUBSECTIONS_PER_SECTION);
692
693 if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
694 "section already deactivated (%#lx + %ld)\n",
695 pfn, nr_pages))
696 return -EINVAL;
697
698 bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
699 return 0;
700}
701
702static bool is_subsection_map_empty(struct mem_section *ms)
703{
704 return bitmap_empty(&ms->usage->subsection_map[0],
705 SUBSECTIONS_PER_SECTION);
706}
707
708static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
709{
710 struct mem_section *ms = __pfn_to_section(pfn);
711 DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
712 unsigned long *subsection_map;
713 int rc = 0;
714
715 subsection_mask_set(map, pfn, nr_pages);
716
717 subsection_map = &ms->usage->subsection_map[0];
718
719 if (bitmap_empty(map, SUBSECTIONS_PER_SECTION))
720 rc = -EINVAL;
721 else if (bitmap_intersects(map, subsection_map, SUBSECTIONS_PER_SECTION))
722 rc = -EEXIST;
723 else
724 bitmap_or(subsection_map, map, subsection_map,
725 SUBSECTIONS_PER_SECTION);
726
727 return rc;
728}
729#else
730struct page * __meminit populate_section_memmap(unsigned long pfn,
731 unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
732{
733 return kvmalloc_node(array_size(sizeof(struct page),
734 PAGES_PER_SECTION), GFP_KERNEL, nid);
735}
736
737static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages,
738 struct vmem_altmap *altmap)
739{
740 kvfree(pfn_to_page(pfn));
741}
742
743static void free_map_bootmem(struct page *memmap)
744{
745 unsigned long maps_section_nr, removing_section_nr, i;
746 unsigned long magic, nr_pages;
747 struct page *page = virt_to_page(memmap);
748
749 nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
750 >> PAGE_SHIFT;
751
752 for (i = 0; i < nr_pages; i++, page++) {
753 magic = (unsigned long) page->freelist;
754
755 BUG_ON(magic == NODE_INFO);
756
757 maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
758 removing_section_nr = page_private(page);
759
760
761
762
763
764
765
766
767
768 if (maps_section_nr != removing_section_nr)
769 put_page_bootmem(page);
770 }
771}
772
773static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
774{
775 return 0;
776}
777
778static bool is_subsection_map_empty(struct mem_section *ms)
779{
780 return true;
781}
782
783static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
784{
785 return 0;
786}
787#endif
788
789
790
791
792
793
794
795
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805static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
806 struct vmem_altmap *altmap)
807{
808 struct mem_section *ms = __pfn_to_section(pfn);
809 bool section_is_early = early_section(ms);
810 struct page *memmap = NULL;
811 bool empty;
812
813 if (clear_subsection_map(pfn, nr_pages))
814 return;
815
816 empty = is_subsection_map_empty(ms);
817 if (empty) {
818 unsigned long section_nr = pfn_to_section_nr(pfn);
819
820
821
822
823
824
825
826
827 if (!PageReserved(virt_to_page(ms->usage))) {
828 kfree(ms->usage);
829 ms->usage = NULL;
830 }
831 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
832
833
834
835
836
837 ms->section_mem_map &= ~SECTION_HAS_MEM_MAP;
838 }
839
840
841
842
843
844 if (!section_is_early)
845 depopulate_section_memmap(pfn, nr_pages, altmap);
846 else if (memmap)
847 free_map_bootmem(memmap);
848
849 if (empty)
850 ms->section_mem_map = (unsigned long)NULL;
851}
852
853static struct page * __meminit section_activate(int nid, unsigned long pfn,
854 unsigned long nr_pages, struct vmem_altmap *altmap)
855{
856 struct mem_section *ms = __pfn_to_section(pfn);
857 struct mem_section_usage *usage = NULL;
858 struct page *memmap;
859 int rc = 0;
860
861 if (!ms->usage) {
862 usage = kzalloc(mem_section_usage_size(), GFP_KERNEL);
863 if (!usage)
864 return ERR_PTR(-ENOMEM);
865 ms->usage = usage;
866 }
867
868 rc = fill_subsection_map(pfn, nr_pages);
869 if (rc) {
870 if (usage)
871 ms->usage = NULL;
872 kfree(usage);
873 return ERR_PTR(rc);
874 }
875
876
877
878
879
880
881
882
883 if (nr_pages < PAGES_PER_SECTION && early_section(ms))
884 return pfn_to_page(pfn);
885
886 memmap = populate_section_memmap(pfn, nr_pages, nid, altmap);
887 if (!memmap) {
888 section_deactivate(pfn, nr_pages, altmap);
889 return ERR_PTR(-ENOMEM);
890 }
891
892 return memmap;
893}
894
895
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912
913int __meminit sparse_add_section(int nid, unsigned long start_pfn,
914 unsigned long nr_pages, struct vmem_altmap *altmap)
915{
916 unsigned long section_nr = pfn_to_section_nr(start_pfn);
917 struct mem_section *ms;
918 struct page *memmap;
919 int ret;
920
921 ret = sparse_index_init(section_nr, nid);
922 if (ret < 0)
923 return ret;
924
925 memmap = section_activate(nid, start_pfn, nr_pages, altmap);
926 if (IS_ERR(memmap))
927 return PTR_ERR(memmap);
928
929
930
931
932
933 page_init_poison(memmap, sizeof(struct page) * nr_pages);
934
935 ms = __nr_to_section(section_nr);
936 set_section_nid(section_nr, nid);
937 section_mark_present(ms);
938
939
940 if (section_nr_to_pfn(section_nr) != start_pfn)
941 memmap = pfn_to_page(section_nr_to_pfn(section_nr));
942 sparse_init_one_section(ms, section_nr, memmap, ms->usage, 0);
943
944 return 0;
945}
946
947#ifdef CONFIG_MEMORY_FAILURE
948static void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
949{
950 int i;
951
952
953
954
955
956
957
958 if (atomic_long_read(&num_poisoned_pages) == 0)
959 return;
960
961 for (i = 0; i < nr_pages; i++) {
962 if (PageHWPoison(&memmap[i])) {
963 num_poisoned_pages_dec();
964 ClearPageHWPoison(&memmap[i]);
965 }
966 }
967}
968#else
969static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
970{
971}
972#endif
973
974void sparse_remove_section(struct mem_section *ms, unsigned long pfn,
975 unsigned long nr_pages, unsigned long map_offset,
976 struct vmem_altmap *altmap)
977{
978 clear_hwpoisoned_pages(pfn_to_page(pfn) + map_offset,
979 nr_pages - map_offset);
980 section_deactivate(pfn, nr_pages, altmap);
981}
982#endif
983