1 #include <stdio.h>
2 #include <assert.h>
3
4 #include <linux/scatterlist.h>
5
6 #define MAX_PAGES (64)
7
set_pages(struct page ** pages,const unsigned * array,unsigned num)8 static void set_pages(struct page **pages, const unsigned *array, unsigned num)
9 {
10 unsigned int i;
11
12 assert(num < MAX_PAGES);
13 for (i = 0; i < num; i++)
14 pages[i] = (struct page *)(unsigned long)
15 ((1 + array[i]) * PAGE_SIZE);
16 }
17
18 #define pfn(...) (unsigned []){ __VA_ARGS__ }
19
main(void)20 int main(void)
21 {
22 const unsigned int sgmax = SCATTERLIST_MAX_SEGMENT;
23 struct test {
24 int alloc_ret;
25 unsigned num_pages;
26 unsigned *pfn;
27 unsigned size;
28 unsigned int max_seg;
29 unsigned int expected_segments;
30 } *test, tests[] = {
31 { -EINVAL, 1, pfn(0), PAGE_SIZE, PAGE_SIZE + 1, 1 },
32 { -EINVAL, 1, pfn(0), PAGE_SIZE, 0, 1 },
33 { -EINVAL, 1, pfn(0), PAGE_SIZE, sgmax + 1, 1 },
34 { 0, 1, pfn(0), PAGE_SIZE, sgmax, 1 },
35 { 0, 1, pfn(0), 1, sgmax, 1 },
36 { 0, 2, pfn(0, 1), 2 * PAGE_SIZE, sgmax, 1 },
37 { 0, 2, pfn(1, 0), 2 * PAGE_SIZE, sgmax, 2 },
38 { 0, 3, pfn(0, 1, 2), 3 * PAGE_SIZE, sgmax, 1 },
39 { 0, 3, pfn(0, 2, 1), 3 * PAGE_SIZE, sgmax, 3 },
40 { 0, 3, pfn(0, 1, 3), 3 * PAGE_SIZE, sgmax, 2 },
41 { 0, 3, pfn(1, 2, 4), 3 * PAGE_SIZE, sgmax, 2 },
42 { 0, 3, pfn(1, 3, 4), 3 * PAGE_SIZE, sgmax, 2 },
43 { 0, 4, pfn(0, 1, 3, 4), 4 * PAGE_SIZE, sgmax, 2 },
44 { 0, 5, pfn(0, 1, 3, 4, 5), 5 * PAGE_SIZE, sgmax, 2 },
45 { 0, 5, pfn(0, 1, 3, 4, 6), 5 * PAGE_SIZE, sgmax, 3 },
46 { 0, 5, pfn(0, 1, 2, 3, 4), 5 * PAGE_SIZE, sgmax, 1 },
47 { 0, 5, pfn(0, 1, 2, 3, 4), 5 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
48 { 0, 6, pfn(0, 1, 2, 3, 4, 5), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
49 { 0, 6, pfn(0, 2, 3, 4, 5, 6), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 4 },
50 { 0, 6, pfn(0, 1, 3, 4, 5, 6), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
51 { 0, 0, NULL, 0, 0, 0 },
52 };
53 unsigned int i;
54
55 for (i = 0, test = tests; test->expected_segments; test++, i++) {
56 struct page *pages[MAX_PAGES];
57 struct sg_table st;
58 int ret;
59
60 set_pages(pages, test->pfn, test->num_pages);
61
62 ret = __sg_alloc_table_from_pages(&st, pages, test->num_pages,
63 0, test->size, test->max_seg,
64 GFP_KERNEL);
65 assert(ret == test->alloc_ret);
66
67 if (test->alloc_ret)
68 continue;
69
70 assert(st.nents == test->expected_segments);
71 assert(st.orig_nents == test->expected_segments);
72
73 sg_free_table(&st);
74 }
75
76 assert(i == (sizeof(tests) / sizeof(tests[0])) - 1);
77
78 return 0;
79 }
80
