[PATCH 4/5] swiotlb: map_page fix for highmem systems

Becky Bruce
2009-03-24T21:45:59Z

The current code calls virt_to_phys() on address that might
be in highmem, which is bad. This wasn't needed, anyway, because
we already have the physical address we need. Get rid of the
now-unused virtual address as well.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
---
lib/swiotlb.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index c152f17..b33180e 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -640,7 +640,6 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
struct dma_attrs *attrs)
{
phys_addr_t phys = page_to_phys(page) + offset;
- void *ptr = page_address(page) + offset;
dma_addr_t dev_addr = swiotlb_phys_to_bus(dev, phys);
void *map;

@@ -651,7 +650,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
* buffering it.
*/
if (!address_needs_mapping(dev, dev_addr, size) &&
- !range_needs_mapping(virt_to_phys(ptr), size))
+ !range_needs_mapping(phys, size))
return dev_addr;

/*
--
1.5.6.6