参照元†
- struct page *page
- unsigned long off
- size_t size
- enum dma_data_direction dir
返り値†
static void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
size_t size, enum dma_data_direction dir)
{
phys_addr_t paddr = page_to_phys(page) + off;
/* FIXME: non-speculating: not required */
/* in any case, don't bother invalidating if DMA to device */
if (dir != DMA_TO_DEVICE) {
outer_inv_range(paddr, paddr + size);
dma_cache_maint_page(page, off, size, dir, dmac_unmap_area);
}
/*
* Mark the D-cache clean for these pages to avoid extra flushing.
*/
if (dir != DMA_TO_DEVICE && size >= PAGE_SIZE) {
unsigned long pfn;
size_t left = size;
pfn = page_to_pfn(page) + off / PAGE_SIZE;
off %= PAGE_SIZE;
if (off) {
pfn++;
left -= PAGE_SIZE - off;
}
while (left >= PAGE_SIZE) {
page = pfn_to_page(pfn++);
set_bit(PG_dcache_clean, &page->flags);
left -= PAGE_SIZE;
}
}
}
コメント†