leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ARC: don't check for HIGHMEM pages in arch_dma_alloc

Browse Source 
__GFP_HIGHMEM flag is cleared by upper layer functions
(in include/linux/dma-mapping.h) so we'll never get a
__GFP_HIGHMEM flag in arch_dma_alloc gfp argument.
That's why alloc_pages will never return highmem page
here.

Get rid of highmem pages handling and cleanup arch_dma_alloc
and arch_dma_free functions.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Eugeniy Paltsev 2018-07-30 19:26:36 +03:00 committed by Vineet Gupta
parent 2b720e99a1
commit dd45210b6d
1 changed files with 14 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
arch/arc/mm/dma.c
View File

@ -24,30 +24,29 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
struct page *page;
phys_addr_t paddr;
void *kvaddr;
int need_coh = 1, need_kvaddr = 0;
bool need_coh = !(attrs & DMA_ATTR_NON_CONSISTENT);
/*
* __GFP_HIGHMEM flag is cleared by upper layer functions
* (in include/linux/dma-mapping.h) so we should never get a
* __GFP_HIGHMEM here.
*/
BUG_ON(gfp & __GFP_HIGHMEM);
page = alloc_pages(gfp, order);
if (!page)
return NULL;
if (attrs & DMA_ATTR_NON_CONSISTENT)
need_coh = 0;
/*
* - A coherent buffer needs MMU mapping to enforce non-cachability
* - A highmem page needs a virtual handle (hence MMU mapping)
* independent of cachability
*/
if (PageHighMem(page) || need_coh)
need_kvaddr = 1;
/* This is linear addr (0x8000_0000 based) */
paddr = page_to_phys(page);
*dma_handle = paddr;
/* This is kernel Virtual address (0x7000_0000 based) */
if (need_kvaddr) {
/*
* A coherent buffer needs MMU mapping to enforce non-cachability.
* kvaddr is kernel Virtual address (0x7000_0000 based).
*/
if (need_coh) {
kvaddr = ioremap_nocache(paddr, size);
if (kvaddr == NULL) {
__free_pages(page, order);
@ -78,11 +77,8 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr,
{
phys_addr_t paddr = dma_handle;
struct page *page = virt_to_page(paddr);
int is_non_coh = 1;
is_non_coh = (attrs & DMA_ATTR_NON_CONSISTENT);
if (PageHighMem(page) || !is_non_coh)
if (!(attrs & DMA_ATTR_NON_CONSISTENT))
iounmap((void __force __iomem *)vaddr);
__free_pages(page, get_order(size));