xref: /linux/tools/testing/scatterlist/main.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 #include <stdio.h>
2 #include <assert.h>
3 
4 #include <linux/scatterlist.h>
5 
6 #define MAX_PAGES (64)
7 
8 struct 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 
18 static 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 
30 static 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 
52 int 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, test->pfn, test->num_pages);
93 
94 		if (test->pfn_app)
95 			ret = sg_alloc_append_table_from_pages(
96 				&append, pages, test->num_pages, 0, test->size,
97 				test->max_seg, left_pages, GFP_KERNEL);
98 		else
99 			ret = sg_alloc_table_from_pages_segment(
100 				&append.sgt, pages, test->num_pages, 0,
101 				test->size, 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, test->pfn_app, test->num_pages);
110 			ret = sg_alloc_append_table_from_pages(
111 				&append, pages, test->num_pages, 0, test->size,
112 				test->max_seg, 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(&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