mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-22 18:44:44 +08:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
37 lines
806 B
C
37 lines
806 B
C
/*
|
|
* Dynamic DMA mapping support.
|
|
*
|
|
* We never have any address translations to worry about, so this
|
|
* is just alloc/free.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/string.h>
|
|
#include <linux/pci.h>
|
|
#include <asm/io.h>
|
|
|
|
void *dma_alloc_coherent(struct device *dev, size_t size,
|
|
dma_addr_t *dma_handle, int gfp)
|
|
{
|
|
void *ret;
|
|
/* ignore region specifiers */
|
|
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
|
|
|
|
if (dev == NULL || (*dev->dma_mask < 0xffffffff))
|
|
gfp |= GFP_DMA;
|
|
ret = (void *)__get_free_pages(gfp, get_order(size));
|
|
|
|
if (ret != NULL) {
|
|
memset(ret, 0, size);
|
|
*dma_handle = virt_to_phys(ret);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void dma_free_coherent(struct device *dev, size_t size,
|
|
void *vaddr, dma_addr_t dma_handle)
|
|
{
|
|
free_pages((unsigned long)vaddr, get_order(size));
|
|
}
|