From: Christoph Hellwig <hch@infradead.org>
To: Jason Wang <jasowang@redhat.com>
Cc: mst@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com,
virtualization@lists.linux.dev, hch@infradead.org
Subject: Re: [PATCH V2 9/9] vduse: switch to use virtio map API instead of DMA API
Date: Thu, 17 Jul 2025 06:25:23 -0700 [thread overview]
Message-ID: <aHj5wwaQHyRAcrcN@infradead.org> (raw)
In-Reply-To: <20250717080237.6518-10-jasowang@redhat.com>
On Thu, Jul 17, 2025 at 04:02:37PM +0800, Jason Wang wrote:
> Lacking the support of device specific mapping supported in virtio,
> VDUSE must trick the DMA API in order to make virtio-vdpa transport
> work. This is done by advertising vDPA device as dma device with a
> VDUSE specific dma_ops even if it doesn't do DMA at all.
>
> This will be fixed by this patch. Thanks to the new mapping operations
> support by virtio and vDPA. VDUSE can simply switch to advertise its
> specific mappings operations to virtio via virtio-vdpa then DMA API is
> not needed for VDUSE any more.
This can now drop the depends on HAS_DMA and ARCH_HAS_DMA_OPS for
VDPA_USER.
next prev parent reply other threads:[~2025-07-17 13:25 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-17 8:02 [PATCH V2 0/9] Refine virtio mapping API Jason Wang
2025-07-17 8:02 ` [PATCH V2 1/9] virtio_ring: constify virtqueue pointer for DMA helpers Jason Wang
2025-07-17 8:02 ` [PATCH V2 2/9] virtio_ring: switch to use dma_{map|unmap}_page() Jason Wang
2025-07-17 8:02 ` [PATCH V2 3/9] virtio: rename dma helpers Jason Wang
2025-07-17 8:02 ` [PATCH V2 4/9] virtio: rename dma_dev to map_token Jason Wang
2025-07-17 8:02 ` [PATCH V2 5/9] virtio_ring: rename dma_handle to map_handle Jason Wang
2025-07-17 8:02 ` [PATCH V2 6/9] virtio: introduce map ops in virtio core Jason Wang
2025-07-17 8:02 ` [PATCH V2 7/9] vdpa: rename dma_dev to map_token Jason Wang
2025-07-17 8:02 ` [PATCH V2 8/9] vdpa: introduce map ops Jason Wang
2025-07-17 8:02 ` [PATCH V2 9/9] vduse: switch to use virtio map API instead of DMA API Jason Wang
2025-07-17 13:25 ` Christoph Hellwig [this message]
2025-07-18 2:05 ` Jason Wang
2025-07-17 13:26 ` [PATCH V2 0/9] Refine virtio mapping API Christoph Hellwig
2025-07-18 2:05 ` Jason Wang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=aHj5wwaQHyRAcrcN@infradead.org \
--to=hch@infradead.org \
--cc=eperezma@redhat.com \
--cc=jasowang@redhat.com \
--cc=mst@redhat.com \
--cc=virtualization@lists.linux.dev \
--cc=xuanzhuo@linux.alibaba.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox