Hi, here is the third version of this patch-set. Previous versions can be found here: V1: https://lore.kernel.org/lkml/20190110134433.15672-1-joro@xxxxxxxxxx/ V2: https://lore.kernel.org/lkml/20190115132257.6426-1-joro@xxxxxxxxxx/ The problem solved here 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. Changes to v2 are: * Check if SWIOTLB is active before returning its limit in dma_direct_max_mapping_size() * Only apply the maximum segment limit in virtio-blk when DMA-API is used for the vring Please review. Thanks, Joerg Joerg Roedel (5): swiotlb: Introduce swiotlb_max_mapping_size() swiotlb: Add is_swiotlb_active() function dma: Introduce dma_max_mapping_size() virtio: Introduce virtio_max_dma_size() virtio-blk: Consider virtio_max_dma_size() for maximum segment size drivers/block/virtio_blk.c | 10 ++++++---- drivers/virtio/virtio_ring.c | 10 ++++++++++ include/linux/dma-mapping.h | 16 ++++++++++++++++ include/linux/swiotlb.h | 11 +++++++++++ include/linux/virtio.h | 2 ++ kernel/dma/direct.c | 11 +++++++++++ kernel/dma/swiotlb.c | 10 ++++++++++ 7 files changed, 66 insertions(+), 4 deletions(-) -- 2.17.1
