This reverts commit ddbd89deb7d32b1fbb879f48d68fda1a8ac58e8e. Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx> --- Documentation/core-api/dma-attributes.rst | 8 -------- include/linux/dma-mapping.h | 8 -------- kernel/dma/swiotlb.c | 3 +-- 3 files changed, 1 insertion(+), 18 deletions(-) diff --git a/Documentation/core-api/dma-attributes.rst b/Documentation/core-api/dma-attributes.rst index 17706dc91ec9..1887d92e8e92 100644 --- a/Documentation/core-api/dma-attributes.rst +++ b/Documentation/core-api/dma-attributes.rst @@ -130,11 +130,3 @@ accesses to DMA buffers in both privileged "supervisor" and unprivileged subsystem that the buffer is fully accessible at the elevated privilege level (and ideally inaccessible or at least read-only at the lesser-privileged levels). - -DMA_ATTR_OVERWRITE ------------------- - -This is a hint to the DMA-mapping subsystem that the device is expected to -overwrite the entire mapped size, thus the caller does not require any of the -previous buffer contents to be preserved. This allows bounce-buffering -implementations to optimise DMA_FROM_DEVICE transfers. diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 6150d11a607e..dca2b1355bb1 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -61,14 +61,6 @@ */ #define DMA_ATTR_PRIVILEGED (1UL << 9) -/* - * This is a hint to the DMA-mapping subsystem that the device is expected - * to overwrite the entire mapped size, thus the caller does not require any - * of the previous buffer contents to be preserved. This allows - * bounce-buffering implementations to optimise DMA_FROM_DEVICE transfers. - */ -#define DMA_ATTR_OVERWRITE (1UL << 10) - /* * A dma_addr_t can hold any valid DMA or bus address for the platform. It can * be given to a device to use as a DMA source or target. It is specific to a diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index bfc56cb21705..f1e7ea160b43 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -628,8 +628,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, mem->slots[index + i].orig_addr = slot_addr(orig_addr, i); tlb_addr = slot_addr(mem->start, index) + offset; if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - (!(attrs & DMA_ATTR_OVERWRITE) || dir == DMA_TO_DEVICE || - dir == DMA_BIDIRECTIONAL)) + (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_TO_DEVICE); return tlb_addr; } -- 2.32.0
