diff options
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 68 |
1 files changed, 10 insertions, 58 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 272e4aef2a86..e40bf1b707e3 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -514,24 +514,8 @@ xen_swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems, } -/* - * Map a set of buffers described by scatterlist in streaming mode for DMA. - * This is the scatter-gather version of the above xen_swiotlb_map_page - * interface. Here the scatter gather list elements are each tagged with the - * appropriate dma address and length. They are obtained via - * sg_dma_{address,length}(SG). - * - * NOTE: An implementation may be able to use a smaller number of - * DMA address/length pairs than there are SG table elements. - * (for example via virtual mapping capabilities) - * The routine returns the number of addr/length pairs actually - * used, at most nents. - * - * Device ownership issues as mentioned above for xen_swiotlb_map_page are the - * same here. - */ static int -xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems, +xen_swiotlb_map_sg(struct device *dev, struct scatterlist *sgl, int nelems, enum dma_data_direction dir, unsigned long attrs) { struct scatterlist *sg; @@ -540,50 +524,18 @@ xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems, BUG_ON(dir == DMA_NONE); for_each_sg(sgl, sg, nelems, i) { - phys_addr_t paddr = sg_phys(sg); - dma_addr_t dev_addr = xen_phys_to_bus(paddr); - - if (swiotlb_force == SWIOTLB_FORCE || - xen_arch_need_swiotlb(hwdev, paddr, dev_addr) || - !dma_capable(hwdev, dev_addr, sg->length) || - range_straddles_page_boundary(paddr, sg->length)) { - phys_addr_t map = swiotlb_tbl_map_single(hwdev, - start_dma_addr, - sg_phys(sg), - sg->length, - dir, attrs); - if (map == DMA_MAPPING_ERROR) { - dev_warn(hwdev, "swiotlb buffer is full\n"); - /* Don't panic here, we expect map_sg users - to do proper error handling. */ - attrs |= DMA_ATTR_SKIP_CPU_SYNC; - xen_swiotlb_unmap_sg(hwdev, sgl, i, dir, attrs); - sg_dma_len(sgl) = 0; - return 0; - } - dev_addr = xen_phys_to_bus(map); - xen_dma_map_page(hwdev, pfn_to_page(map >> PAGE_SHIFT), - dev_addr, - map & ~PAGE_MASK, - sg->length, - dir, - attrs); - sg->dma_address = dev_addr; - } else { - /* we are not interested in the dma_addr returned by - * xen_dma_map_page, only in the potential cache flushes executed - * by the function. */ - xen_dma_map_page(hwdev, pfn_to_page(paddr >> PAGE_SHIFT), - dev_addr, - paddr & ~PAGE_MASK, - sg->length, - dir, - attrs); - sg->dma_address = dev_addr; - } + sg->dma_address = xen_swiotlb_map_page(dev, sg_page(sg), + sg->offset, sg->length, dir, attrs); + if (sg->dma_address == DMA_MAPPING_ERROR) + goto out_unmap; sg_dma_len(sg) = sg->length; } + return nelems; +out_unmap: + xen_swiotlb_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC); + sg_dma_len(sgl) = 0; + return 0; } /* |
