1#include <stdio.h>
2#include <assert.h>
3
4#include <linux/scatterlist.h>
5
6#define MAX_PAGES (64)
7
8struct test {
9 int alloc_ret;
10 unsigned num_pages;
11 unsigned *pfn;
12 unsigned *pfn_app;
13 unsigned size;
14 unsigned int max_seg;
15 unsigned int expected_segments;
16};
17
18static void set_pages(struct page **pages, const unsigned *array, unsigned num)
19{
20 unsigned int i;
21
22 assert(num < MAX_PAGES);
23 for (i = 0; i < num; i++)
24 pages[i] = (struct page *)(unsigned long)
25 ((1 + array[i]) * PAGE_SIZE);
26}
27
28#define pfn(...) (unsigned []){ __VA_ARGS__ }
29
30static void fail(struct test *test, struct sg_table *st, const char *cond)
31{
32 unsigned int i;
33
34 fprintf(stderr, "Failed on '%s'!\n\n", cond);
35
36 printf("size = %u, max segment = %u, expected nents = %u\nst->nents = %u, st->orig_nents= %u\n",
37 test->size, test->max_seg, test->expected_segments, st->nents,
38 st->orig_nents);
39
40 printf("%u input PFNs:", test->num_pages);
41 for (i = 0; i < test->num_pages; i++)
42 printf(" %x", test->pfn[i]);
43 printf("\n");
44
45 exit(1);
46}
47
48#define VALIDATE(cond, st, test) \
49 if (!(cond)) \
50 fail((test), (st), #cond);
51
52int main(void)
53{
54 const unsigned int sgmax = UINT_MAX;
55 struct test *test, tests[] = {
56 { -EINVAL, 1, pfn(0), NULL, PAGE_SIZE, 0, 1 },
57 { 0, 1, pfn(0), NULL, PAGE_SIZE, PAGE_SIZE + 1, 1 },
58 { 0, 1, pfn(0), NULL, PAGE_SIZE, sgmax, 1 },
59 { 0, 1, pfn(0), NULL, 1, sgmax, 1 },
60 { 0, 2, pfn(0, 1), NULL, 2 * PAGE_SIZE, sgmax, 1 },
61 { 0, 2, pfn(1, 0), NULL, 2 * PAGE_SIZE, sgmax, 2 },
62 { 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
63 { 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
64 { 0, 3, pfn(0, 1, 2), pfn(3, 4, 5), 3 * PAGE_SIZE, sgmax, 1 },
65 { 0, 3, pfn(0, 1, 2), pfn(4, 5, 6), 3 * PAGE_SIZE, sgmax, 2 },
66 { 0, 3, pfn(0, 2, 1), NULL, 3 * PAGE_SIZE, sgmax, 3 },
67 { 0, 3, pfn(0, 1, 3), NULL, 3 * PAGE_SIZE, sgmax, 2 },
68 { 0, 3, pfn(1, 2, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
69 { 0, 3, pfn(1, 3, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
70 { 0, 4, pfn(0, 1, 3, 4), NULL, 4 * PAGE_SIZE, sgmax, 2 },
71 { 0, 5, pfn(0, 1, 3, 4, 5), NULL, 5 * PAGE_SIZE, sgmax, 2 },
72 { 0, 5, pfn(0, 1, 3, 4, 6), NULL, 5 * PAGE_SIZE, sgmax, 3 },
73 { 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, sgmax, 1 },
74 { 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, 2 * PAGE_SIZE,
75 3 },
76 { 0, 6, pfn(0, 1, 2, 3, 4, 5), NULL, 6 * PAGE_SIZE,
77 2 * PAGE_SIZE, 3 },
78 { 0, 6, pfn(0, 2, 3, 4, 5, 6), NULL, 6 * PAGE_SIZE,
79 2 * PAGE_SIZE, 4 },
80 { 0, 6, pfn(0, 1, 3, 4, 5, 6), pfn(7, 8, 9, 10, 11, 12),
81 6 * PAGE_SIZE, 12 * PAGE_SIZE, 2 },
82 { 0, 0, NULL, NULL, 0, 0, 0 },
83 };
84 unsigned int i;
85
86 for (i = 0, test = tests; test->expected_segments; test++, i++) {
87 int left_pages = test->pfn_app ? test->num_pages : 0;
88 struct sg_append_table append = {};
89 struct page *pages[MAX_PAGES];
90 int ret;
91
92 set_pages(pages, array: test->pfn, num: test->num_pages);
93
94 if (test->pfn_app)
95 ret = sg_alloc_append_table_from_pages(
96 sgt: &append, pages, n_pages: test->num_pages, offset: 0, size: test->size,
97 max_segment: test->max_seg, left_pages, GFP_KERNEL);
98 else
99 ret = sg_alloc_table_from_pages_segment(
100 sgt: &append.sgt, pages, n_pages: test->num_pages, offset: 0,
101 size: test->size, max_segment: test->max_seg, GFP_KERNEL);
102
103 assert(ret == test->alloc_ret);
104
105 if (test->alloc_ret)
106 continue;
107
108 if (test->pfn_app) {
109 set_pages(pages, array: test->pfn_app, num: test->num_pages);
110 ret = sg_alloc_append_table_from_pages(
111 sgt: &append, pages, n_pages: test->num_pages, offset: 0, size: test->size,
112 max_segment: test->max_seg, left_pages: 0, GFP_KERNEL);
113
114 assert(ret == test->alloc_ret);
115 }
116
117 VALIDATE(append.sgt.nents == test->expected_segments,
118 &append.sgt, test);
119 if (!test->pfn_app)
120 VALIDATE(append.sgt.orig_nents ==
121 test->expected_segments,
122 &append.sgt, test);
123
124 if (test->pfn_app)
125 sg_free_append_table(sgt: &append);
126 else
127 sg_free_table(&append.sgt);
128 }
129
130 assert(i == (sizeof(tests) / sizeof(tests[0])) - 1);
131
132 return 0;
133}
134

source code of linux/tools/testing/scatterlist/main.c