diff options
| author | Christoph Hellwig <hch@lst.de> | 2018-10-19 08:51:53 +0200 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2018-10-19 08:53:05 +0200 |
| commit | a4a4330db46a17289cf2ca5f9fb153d536267b97 (patch) | |
| tree | d3e807bd0fe1d8fb38c800f0696711b8423d57ff /kernel/dma | |
| parent | fafadcd16595c1df82df399f62421718ec9bf70a (diff) | |
swiotlb: add support for non-coherent DMA
Handle architectures that are not cache coherent directly in the main
swiotlb code by calling arch_sync_dma_for_{device,cpu} in all the right
places from the various dma_map/unmap/sync methods when the device is
non-coherent.
Because swiotlb now uses dma_direct_alloc for the coherent allocation
that side is already taken care of by the dma-direct code calling into
arch_dma_{alloc,free} for devices that are non-coherent.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/swiotlb.c | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 1a01b0ac0a5e..ebecaf255ea2 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -21,6 +21,7 @@ #include <linux/cache.h> #include <linux/dma-direct.h> +#include <linux/dma-noncoherent.h> #include <linux/mm.h> #include <linux/export.h> #include <linux/spinlock.h> @@ -671,11 +672,17 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, * we can safely return the device addr and not worry about bounce * buffering it. */ - if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE) - return dev_addr; + if (!dma_capable(dev, dev_addr, size) || + swiotlb_force == SWIOTLB_FORCE) { + trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); + dev_addr = swiotlb_bounce_page(dev, &phys, size, dir, attrs); + } + + if (!dev_is_dma_coherent(dev) && + (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) + arch_sync_dma_for_device(dev, phys, size, dir); - trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); - return swiotlb_bounce_page(dev, &phys, size, dir, attrs); + return dev_addr; } /* @@ -694,6 +701,10 @@ void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, BUG_ON(dir == DMA_NONE); + if (!dev_is_dma_coherent(hwdev) && + (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0) + arch_sync_dma_for_cpu(hwdev, paddr, size, dir); + if (is_swiotlb_buffer(paddr)) { swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs); return; @@ -730,15 +741,17 @@ swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, BUG_ON(dir == DMA_NONE); - if (is_swiotlb_buffer(paddr)) { + if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_CPU) + arch_sync_dma_for_cpu(hwdev, paddr, size, dir); + + if (is_swiotlb_buffer(paddr)) swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target); - return; - } - if (dir != DMA_FROM_DEVICE) - return; + if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_DEVICE) + arch_sync_dma_for_device(hwdev, paddr, size, dir); - dma_mark_clean(phys_to_virt(paddr), size); + if (!is_swiotlb_buffer(paddr) && dir == DMA_FROM_DEVICE) + dma_mark_clean(phys_to_virt(paddr), size); } void |