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

On Wed, Jan 23, 2019 at 05:30:44PM +0100, Joerg Roedel wrote:

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@8bytes.org/ (local)

	V2: https://lore.kernel.org/lkml/20190115132257.6426-1-joro@8bytes.org/ (local)

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 ++++++++++

The kvm-devel mailing list should have been copied on those.

When you do can you please put 'Reviewed-by: Konrad Rzeszutek Wilk
[off-list ref]' on all of them?

Thank you!

P.S.
Christopher, I am assuming you are OK with this idea, if so - and once
the owners of 'virtio' Ack, do you want to put it in my tree?

Thanks!

 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