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, 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