PMM - alloc two pages

This commit is contained in:
Thomas Lovén 2017-12-21 16:15:55 +01:00
parent e7bdea771b
commit 1daf8ed47b
2 changed files with 28 additions and 2 deletions

View File

@ -4,12 +4,13 @@ uintptr_t *first = 0;
void pmm_free(void *c)
{
*(uintptr_t *)c = (uintptr_t)first;
first = c;
}
void *pmm_alloc()
{
void *c = first;
first = 0;
first = (uintptr_t *)(c?*(uintptr_t *)c:0);
return c;
}

View File

@ -5,7 +5,7 @@
struct {
uint8_t data[PAGE_SIZE];
}__attribute__((packed)) mem[4];
}__attribute__((packed)) mem[2];
TEST(alloc_returns_freed_page)
{
@ -25,3 +25,28 @@ TEST(alloc_zero_after_all_free_pages)
void *a = pmm_alloc();
ASSERT_EQ_PTR(a, 0);
}
TEST(alloc_two_pages___first_page_is_not_zero)
{
pmm_free(&mem[0]);
pmm_free(&mem[1]);
void *a = pmm_alloc();
pmm_alloc();
ASSERT_NEQ_PTR(a, 0);
}
TEST(alloc_two_pages___second_page_is_not_zero)
{
pmm_free(&mem[0]);
pmm_free(&mem[1]);
pmm_alloc();
void *a = pmm_alloc();
ASSERT_NEQ_PTR(a, 0);
}
TEST(alloc_two_pages___doesnt_return_same_page_twice)
{
pmm_free(&mem[0]);
pmm_free(&mem[1]);
void *a = pmm_alloc();
void *b = pmm_alloc();
ASSERT_NEQ_PTR(a, b);
}