blob: 14b19c4161f4586d74d8c81fbc1d6265ac1a5b48 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Dynamic DMA mapping support.
3 *
4 * We never have any address translations to worry about, so this
5 * is just alloc/free.
6 */
7
8#include <linux/types.h>
9#include <linux/mm.h>
10#include <linux/string.h>
11#include <linux/pci.h>
12#include <asm/io.h>
13
14void *dma_alloc_coherent(struct device *dev, size_t size,
15 dma_addr_t *dma_handle, int gfp)
16{
17 void *ret;
18 /* ignore region specifiers */
19 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
20
21 if (dev == NULL || (*dev->dma_mask < 0xffffffff))
22 gfp |= GFP_DMA;
23 ret = (void *)__get_free_pages(gfp, get_order(size));
24
25 if (ret != NULL) {
26 memset(ret, 0, size);
27 *dma_handle = virt_to_phys(ret);
28 }
29 return ret;
30}
31
32void dma_free_coherent(struct device *dev, size_t size,
33 void *vaddr, dma_addr_t dma_handle)
34{
35 free_pages((unsigned long)vaddr, get_order(size));
36}