Re: [PATCH 3/3] virtio_pci: Use the DMA API

From	Joerg Roedel <jroedel@suse.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH 3/3] virtio_pci: Use the DMA API
Date	2015-10-28 03:30 +0100
Message-ID	<qooEW-4Wx-15@gated-at.bofh.it> (permalink)
References	<qonzc-4kh-3@gated-at.bofh.it> <qonzc-4kh-15@gated-at.bofh.it> <qoovf-4Tc-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wed, Oct 28, 2015 at 11:15:30AM +0900, Joerg Roedel wrote:
> Same here, you need to call the dma_sync* functions when passing data
> from/to the virtio-device.

Okay, forget about this comment. This patch only converts to
dma_coherent allocations, which don't need synchronization.

> I think a good test for that is to boot a virtio kvm-guest with
> swiotlb=force and see if it still works.

But this holds, Its a good way to test if your changes work with
bounce-buffering. Together with DMA_API_DEBUG you also see if your
specified dma_directions are right.

	Joerg

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Thread

[PATCH 3/3] virtio_pci: Use the DMA API Andy Lutomirski <luto@kernel.org> - 2015-10-28 02:20 +0100
  Re: [PATCH 3/3] virtio_pci: Use the DMA API Joerg Roedel <jroedel@suse.de> - 2015-10-28 03:20 +0100
    Re: [PATCH 3/3] virtio_pci: Use the DMA API Joerg Roedel <jroedel@suse.de> - 2015-10-28 03:30 +0100
    Re: [PATCH 3/3] virtio_pci: Use the DMA API David Woodhouse <dwmw2@infradead.org> - 2015-10-28 03:30 +0100
      Re: [PATCH 3/3] virtio_pci: Use the DMA API Joerg Roedel <jroedel@suse.de> - 2015-10-28 04:00 +0100

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