参照元†
- struct page *page
- size_t size
返り値†
static void __dma_clear_buffer(struct page *page, size_t size)
{
/*
* Ensure that the allocated pages are zeroed, and that any data
* lurking in the kernel direct-mapped region is invalidated.
*/
if (PageHighMem(page)) {
phys_addr_t base = __pfn_to_phys(page_to_pfn(page));
phys_addr_t end = base + size;
while (size > 0) {
void *ptr = kmap_atomic(page);
memset(ptr, 0, PAGE_SIZE);
dmac_flush_range(ptr, ptr + PAGE_SIZE);
kunmap_atomic(ptr);
page++;
size -= PAGE_SIZE;
}
outer_flush_range(base, end);
} else {
void *ptr = page_address(page);
memset(ptr, 0, size);
dmac_flush_range(ptr, ptr + size);
outer_flush_range(__pa(ptr), __pa(ptr) + size);
}
}
コメント†