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Diffstat (limited to 'arch/tile/kernel/pci-dma.c')
-rw-r--r--arch/tile/kernel/pci-dma.c38
1 files changed, 19 insertions, 19 deletions
diff --git a/arch/tile/kernel/pci-dma.c b/arch/tile/kernel/pci-dma.c
index 5ad5e13b0fa6..658752b2835e 100644
--- a/arch/tile/kernel/pci-dma.c
+++ b/arch/tile/kernel/pci-dma.c
@@ -86,6 +86,21 @@ EXPORT_SYMBOL(dma_free_coherent);
* can count on nothing having been touched.
*/
+/* Flush a PA range from cache page by page. */
+static void __dma_map_pa_range(dma_addr_t dma_addr, size_t size)
+{
+ struct page *page = pfn_to_page(PFN_DOWN(dma_addr));
+ size_t bytesleft = PAGE_SIZE - (dma_addr & (PAGE_SIZE - 1));
+
+ while ((ssize_t)size > 0) {
+ /* Flush the page. */
+ homecache_flush_cache(page++, 0);
+
+ /* Figure out if we need to continue on the next page. */
+ size -= bytesleft;
+ bytesleft = PAGE_SIZE;
+ }
+}
/*
* dma_map_single can be passed any memory address, and there appear
@@ -97,26 +112,12 @@ EXPORT_SYMBOL(dma_free_coherent);
dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction)
{
- struct page *page;
- dma_addr_t dma_addr;
- int thispage;
+ dma_addr_t dma_addr = __pa(ptr);
BUG_ON(!valid_dma_direction(direction));
WARN_ON(size == 0);
- dma_addr = __pa(ptr);
-
- /* We might have been handed a buffer that wraps a page boundary */
- while ((int)size > 0) {
- /* The amount to flush that's on this page */
- thispage = PAGE_SIZE - ((unsigned long)ptr & (PAGE_SIZE - 1));
- thispage = min((int)thispage, (int)size);
- /* Is this valid for any page we could be handed? */
- page = pfn_to_page(kaddr_to_pfn(ptr));
- homecache_flush_cache(page, 0);
- ptr += thispage;
- size -= thispage;
- }
+ __dma_map_pa_range(dma_addr, size);
return dma_addr;
}
@@ -140,10 +141,8 @@ int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
WARN_ON(nents == 0 || sglist->length == 0);
for_each_sg(sglist, sg, nents, i) {
- struct page *page;
sg->dma_address = sg_phys(sg);
- page = pfn_to_page(sg->dma_address >> PAGE_SHIFT);
- homecache_flush_cache(page, 0);
+ __dma_map_pa_range(sg->dma_address, sg->length);
}
return nents;
@@ -163,6 +162,7 @@ dma_addr_t dma_map_page(struct device *dev, struct page *page,
{
BUG_ON(!valid_dma_direction(direction));
+ BUG_ON(offset + size > PAGE_SIZE);
homecache_flush_cache(page, 0);
return page_to_pa(page) + offset;