[PATCH 0/5 v3] Fix virtio-blk issue with SWIOTLB

[Joerg Roedel]

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