[PATCH 06/13] x86/amd_gart: use dma_direct_{alloc,free}

Christoph Hellwig
2018-03-05T17:50:34Z

This gains support for CMA allocations for the force_iommu case, and
cleans up the code a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/x86/kernel/amd_gart_64.c | 36 ++++++++++++++----------------------
1 file changed, 14 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c
index 79ac6caaaabb..f299d8a479bb 100644
--- a/arch/x86/kernel/amd_gart_64.c
+++ b/arch/x86/kernel/amd_gart_64.c
@@ -480,29 +480,21 @@ static void *
gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
gfp_t flag, unsigned long attrs)
{
- dma_addr_t paddr;
- unsigned long align_mask;
- struct page *page;
-
- if (force_iommu && dev->coherent_dma_mask > DMA_BIT_MASK(24)) {
- flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
- page = alloc_pages(flag | __GFP_ZERO, get_order(size));
- if (!page)
- return NULL;
-
- align_mask = (1UL << get_order(size)) - 1;
- paddr = dma_map_area(dev, page_to_phys(page), size,
- DMA_BIDIRECTIONAL, align_mask);
-
- flush_gart();
- if (paddr != bad_dma_addr) {
- *dma_addr = paddr;
- return page_address(page);
- }
- __free_pages(page, get_order(size));
- } else
- return dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+ void *vaddr;
+
+ vaddr = dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+ if (!vaddr ||
+ !force_iommu || dev->coherent_dma_mask <= DMA_BIT_MASK(24))
+ return vaddr;

+ *dma_addr = dma_map_area(dev, virt_to_phys(vaddr), size,
+ DMA_BIDIRECTIONAL, (1UL << get_order(size)) - 1);
+ flush_gart();
+ if (unlikely(*dma_addr == bad_dma_addr))
+ goto out_free;
+ return vaddr;
+out_free:
+ dma_direct_free(dev, size, vaddr, *dma_addr, attrs);
return NULL;
}

--
2.14.2