tools/testing/scatterlist/main.c

   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, 1 },
  59                 { 0, 1, pfn(0), NULL, PAGE_SIZE, sgmax, 1 },
  60                 { 0, 1, pfn(0), NULL, 1, sgmax, 1 },
  61                 { 0, 2, pfn(0, 1), NULL, 2 * PAGE_SIZE, sgmax, 1 },
  62                 { 0, 2, pfn(1, 0), NULL, 2 * PAGE_SIZE, sgmax, 2 },
  63                 { 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
  64                 { 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
  65                 { 0, 3, pfn(0, 1, 2), pfn(3, 4, 5), 3 * PAGE_SIZE, sgmax, 1 },
  66                 { 0, 3, pfn(0, 1, 2), pfn(4, 5, 6), 3 * PAGE_SIZE, sgmax, 2 },
  67                 { 0, 3, pfn(0, 2, 1), NULL, 3 * PAGE_SIZE, sgmax, 3 },
  68                 { 0, 3, pfn(0, 1, 3), NULL, 3 * PAGE_SIZE, sgmax, 2 },
  69                 { 0, 3, pfn(1, 2, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
  70                 { 0, 3, pfn(1, 3, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
  71                 { 0, 4, pfn(0, 1, 3, 4), NULL, 4 * PAGE_SIZE, sgmax, 2 },
  72                 { 0, 5, pfn(0, 1, 3, 4, 5), NULL, 5 * PAGE_SIZE, sgmax, 2 },
  73                 { 0, 5, pfn(0, 1, 3, 4, 6), NULL, 5 * PAGE_SIZE, sgmax, 3 },
  74                 { 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, sgmax, 1 },
  75                 { 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, 2 * PAGE_SIZE,
  76                   3 },
  77                 { 0, 6, pfn(0, 1, 2, 3, 4, 5), NULL, 6 * PAGE_SIZE,
  78                   2 * PAGE_SIZE, 3 },
  79                 { 0, 6, pfn(0, 2, 3, 4, 5, 6), NULL, 6 * PAGE_SIZE,
  80                   2 * PAGE_SIZE, 4 },
  81                 { 0, 6, pfn(0, 1, 3, 4, 5, 6), pfn(7, 8, 9, 10, 11, 12),
  82                   6 * PAGE_SIZE, 12 * PAGE_SIZE, 2 },
  83                 { 0, 0, NULL, NULL, 0, 0, 0 },
  84         };
  85         unsigned int i;
  86
  87         for (i = 0, test = tests; test->expected_segments; test++, i++) {
  88                 int left_pages = test->pfn_app ? test->num_pages : 0;
  89                 struct page *pages[MAX_PAGES];
  90                 struct sg_table st;
  91                 struct scatterlist *sg;
  92
  93                 set_pages(pages, test->pfn, test->num_pages);
  94
  95                 sg = __sg_alloc_table_from_pages(&st, pages, test->num_pages, 0,
  96                                 test->size, test->max_seg, NULL, left_pages, GFP_KERNEL);
  97                 assert(PTR_ERR_OR_ZERO(sg) == test->alloc_ret);
  98
  99                 if (test->alloc_ret)
 100                         continue;
 101
 102                 if (test->pfn_app) {
 103                         set_pages(pages, test->pfn_app, test->num_pages);
 104                         sg = __sg_alloc_table_from_pages(&st, pages, test->num_pages, 0,
 105                                         test->size, test->max_seg, sg, 0, GFP_KERNEL);
 106
 107                         assert(PTR_ERR_OR_ZERO(sg) == test->alloc_ret);
 108                 }
 109
 110                 VALIDATE(st.nents == test->expected_segments, &st, test);
 111                 if (!test->pfn_app)
 112                         VALIDATE(st.orig_nents == test->expected_segments, &st, test);
 113
 114                 sg_free_table(&st);
 115         }
 116
 117         assert(i == (sizeof(tests) / sizeof(tests[0])) - 1);
 118
 119         return 0;
 120 }