https://github.com/torvalds/linux
Tip revision: af2d861d4cd2a4da5137f795ee3509e6f944a25b authored by Linus Torvalds on 24 April 2022, 21:51:22 UTC
Linux 5.18-rc4
Linux 5.18-rc4
Tip revision: af2d861
main.c
#include <stdio.h>
#include <assert.h>
#include <linux/scatterlist.h>
#define MAX_PAGES (64)
struct test {
int alloc_ret;
unsigned num_pages;
unsigned *pfn;
unsigned *pfn_app;
unsigned size;
unsigned int max_seg;
unsigned int expected_segments;
};
static void set_pages(struct page **pages, const unsigned *array, unsigned num)
{
unsigned int i;
assert(num < MAX_PAGES);
for (i = 0; i < num; i++)
pages[i] = (struct page *)(unsigned long)
((1 + array[i]) * PAGE_SIZE);
}
#define pfn(...) (unsigned []){ __VA_ARGS__ }
static void fail(struct test *test, struct sg_table *st, const char *cond)
{
unsigned int i;
fprintf(stderr, "Failed on '%s'!\n\n", cond);
printf("size = %u, max segment = %u, expected nents = %u\nst->nents = %u, st->orig_nents= %u\n",
test->size, test->max_seg, test->expected_segments, st->nents,
st->orig_nents);
printf("%u input PFNs:", test->num_pages);
for (i = 0; i < test->num_pages; i++)
printf(" %x", test->pfn[i]);
printf("\n");
exit(1);
}
#define VALIDATE(cond, st, test) \
if (!(cond)) \
fail((test), (st), #cond);
int main(void)
{
const unsigned int sgmax = UINT_MAX;
struct test *test, tests[] = {
{ -EINVAL, 1, pfn(0), NULL, PAGE_SIZE, 0, 1 },
{ 0, 1, pfn(0), NULL, PAGE_SIZE, PAGE_SIZE + 1, 1 },
{ 0, 1, pfn(0), NULL, PAGE_SIZE, sgmax, 1 },
{ 0, 1, pfn(0), NULL, 1, sgmax, 1 },
{ 0, 2, pfn(0, 1), NULL, 2 * PAGE_SIZE, sgmax, 1 },
{ 0, 2, pfn(1, 0), NULL, 2 * PAGE_SIZE, sgmax, 2 },
{ 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
{ 0, 3, pfn(0, 1, 2), NULL, 3 * PAGE_SIZE, sgmax, 1 },
{ 0, 3, pfn(0, 1, 2), pfn(3, 4, 5), 3 * PAGE_SIZE, sgmax, 1 },
{ 0, 3, pfn(0, 1, 2), pfn(4, 5, 6), 3 * PAGE_SIZE, sgmax, 2 },
{ 0, 3, pfn(0, 2, 1), NULL, 3 * PAGE_SIZE, sgmax, 3 },
{ 0, 3, pfn(0, 1, 3), NULL, 3 * PAGE_SIZE, sgmax, 2 },
{ 0, 3, pfn(1, 2, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
{ 0, 3, pfn(1, 3, 4), NULL, 3 * PAGE_SIZE, sgmax, 2 },
{ 0, 4, pfn(0, 1, 3, 4), NULL, 4 * PAGE_SIZE, sgmax, 2 },
{ 0, 5, pfn(0, 1, 3, 4, 5), NULL, 5 * PAGE_SIZE, sgmax, 2 },
{ 0, 5, pfn(0, 1, 3, 4, 6), NULL, 5 * PAGE_SIZE, sgmax, 3 },
{ 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, sgmax, 1 },
{ 0, 5, pfn(0, 1, 2, 3, 4), NULL, 5 * PAGE_SIZE, 2 * PAGE_SIZE,
3 },
{ 0, 6, pfn(0, 1, 2, 3, 4, 5), NULL, 6 * PAGE_SIZE,
2 * PAGE_SIZE, 3 },
{ 0, 6, pfn(0, 2, 3, 4, 5, 6), NULL, 6 * PAGE_SIZE,
2 * PAGE_SIZE, 4 },
{ 0, 6, pfn(0, 1, 3, 4, 5, 6), pfn(7, 8, 9, 10, 11, 12),
6 * PAGE_SIZE, 12 * PAGE_SIZE, 2 },
{ 0, 0, NULL, NULL, 0, 0, 0 },
};
unsigned int i;
for (i = 0, test = tests; test->expected_segments; test++, i++) {
int left_pages = test->pfn_app ? test->num_pages : 0;
struct sg_append_table append = {};
struct page *pages[MAX_PAGES];
int ret;
set_pages(pages, test->pfn, test->num_pages);
if (test->pfn_app)
ret = sg_alloc_append_table_from_pages(
&append, pages, test->num_pages, 0, test->size,
test->max_seg, left_pages, GFP_KERNEL);
else
ret = sg_alloc_table_from_pages_segment(
&append.sgt, pages, test->num_pages, 0,
test->size, test->max_seg, GFP_KERNEL);
assert(ret == test->alloc_ret);
if (test->alloc_ret)
continue;
if (test->pfn_app) {
set_pages(pages, test->pfn_app, test->num_pages);
ret = sg_alloc_append_table_from_pages(
&append, pages, test->num_pages, 0, test->size,
test->max_seg, 0, GFP_KERNEL);
assert(ret == test->alloc_ret);
}
VALIDATE(append.sgt.nents == test->expected_segments,
&append.sgt, test);
if (!test->pfn_app)
VALIDATE(append.sgt.orig_nents ==
test->expected_segments,
&append.sgt, test);
if (test->pfn_app)
sg_free_append_table(&append);
else
sg_free_table(&append.sgt);
}
assert(i == (sizeof(tests) / sizeof(tests[0])) - 1);
return 0;
}