Hi, here is the second version of my patch-set to fix a DMA mapping size issue triggered by the virtio-blk driver. The problem is a limitation of the SWIOTLB implementation, which does not support allocations larger than 256kb. When the virtio-blk driver tries to read/write a block larger than that, the allocation of the dma-handle fails and an IO error is reported. v1 of the patch-set can be found here: https://lore.kernel.org/lkml/20190110134433.15672-1-joro@xxxxxxxxxx/ The change to v1 is that the maximum mapping size is now officially propagated through the DMA-API, as suggested by Christoph Hellwig. Please review. Thanks, Joerg Joerg Roedel (3): swiotlb: Introduce swiotlb_max_mapping_size() dma: Introduce dma_max_mapping_size() virtio-blk: Consider dma_max_mapping_size() for maximum segment size drivers/block/virtio_blk.c | 10 ++++++---- include/linux/dma-mapping.h | 16 ++++++++++++++++ include/linux/swiotlb.h | 5 +++++ kernel/dma/direct.c | 10 ++++++++++ kernel/dma/swiotlb.c | 5 +++++ 5 files changed, 42 insertions(+), 4 deletions(-) -- 2.17.1 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization