x86: gart alloc_coherent does virtual mapppings only when necessary
gart alloc_coherent need to do virtual mapppings only when an
allocated buffer is not DMA-capable for a device.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 9972c42..9739d56 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -505,15 +505,23 @@
gfp_t flag)
{
void *vaddr;
+ dma_addr_t paddr;
unsigned long align_mask;
+ u64 dma_mask = dma_alloc_coherent_mask(dev, flag);
vaddr = (void *)__get_free_pages(flag | __GFP_ZERO, get_order(size));
if (!vaddr)
return NULL;
+ paddr = virt_to_phys(vaddr);
+ if (is_buffer_dma_capable(dma_mask, paddr, size)) {
+ *dma_addr = paddr;
+ return vaddr;
+ }
+
align_mask = (1UL << get_order(size)) - 1;
- *dma_addr = dma_map_area(dev, __pa(vaddr), size, DMA_BIDIRECTIONAL,
+ *dma_addr = dma_map_area(dev, paddr, size, DMA_BIDIRECTIONAL,
align_mask, dma_mask);
flush_gart();