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30#if defined(CONFIG_SMP) && defined(CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK)
31#error "contiguous percpu allocation is incompatible with paged first chunk"
32#endif
33
34#include <linux/log2.h>
35
36static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size)
37{
38 unsigned int cpu;
39
40 for_each_possible_cpu(cpu)
41 memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size);
42
43 return 0;
44}
45
46static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size)
47{
48
49}
50
51static struct pcpu_chunk *pcpu_create_chunk(void)
52{
53 const int nr_pages = pcpu_group_sizes[0] >> PAGE_SHIFT;
54 struct pcpu_chunk *chunk;
55 struct page *pages;
56 int i;
57
58 chunk = pcpu_alloc_chunk();
59 if (!chunk)
60 return NULL;
61
62 pages = alloc_pages(GFP_KERNEL, order_base_2(nr_pages));
63 if (!pages) {
64 pcpu_free_chunk(chunk);
65 return NULL;
66 }
67
68 for (i = 0; i < nr_pages; i++)
69 pcpu_set_page_chunk(nth_page(pages, i), chunk);
70
71 chunk->data = pages;
72 chunk->base_addr = page_address(pages) - pcpu_group_offsets[0];
73 return chunk;
74}
75
76static void pcpu_destroy_chunk(struct pcpu_chunk *chunk)
77{
78 const int nr_pages = pcpu_group_sizes[0] >> PAGE_SHIFT;
79
80 if (chunk && chunk->data)
81 __free_pages(chunk->data, order_base_2(nr_pages));
82 pcpu_free_chunk(chunk);
83}
84
85static struct page *pcpu_addr_to_page(void *addr)
86{
87 return virt_to_page(addr);
88}
89
90static int __init pcpu_verify_alloc_info(const struct pcpu_alloc_info *ai)
91{
92 size_t nr_pages, alloc_pages;
93
94
95 if (ai->nr_groups != 1) {
96 printk(KERN_CRIT "percpu: can't handle more than one groups\n");
97 return -EINVAL;
98 }
99
100 nr_pages = (ai->groups[0].nr_units * ai->unit_size) >> PAGE_SHIFT;
101 alloc_pages = roundup_pow_of_two(nr_pages);
102
103 if (alloc_pages > nr_pages)
104 printk(KERN_WARNING "percpu: wasting %zu pages per chunk\n",
105 alloc_pages - nr_pages);
106
107 return 0;
108}
109