On 02/07/2024 10:09 am, Leon Romanovsky wrote: [...]
+static inline dma_addr_t nvme_dma_link_page(struct page *page, + unsigned int poffset, + unsigned int len, + struct nvme_iod *iod) { - int i; - struct scatterlist *sg; + struct dma_iova_attrs *iova = &iod->dma_map->iova; + struct dma_iova_state *state = &iod->dma_map->state; + dma_addr_t dma_addr; + int ret; + + if (iod->dma_map->use_iova) { + phys_addr_t phys = page_to_phys(page) + poffset;
Yeah, there's no way this can possibly work. You can't do the dev_use_swiotlb() check up-front based on some overall DMA operation size, but then build that operation out of arbitrarily small fragments of different physical pages that *could* individually need bouncing to not break coherency.
Thanks, Robin.
+ + dma_addr = state->iova->addr + state->range_size; + ret = dma_link_range(&iod->dma_map->state, phys, len); + if (ret) + return DMA_MAPPING_ERROR; + } else { + dma_addr = dma_map_page_attrs(iova->dev, page, poffset, len, + iova->dir, iova->attrs); + } + return dma_addr; +}