linux-kernel - Re: [PATCH V6 0/9] Refine virtio mapping API

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CACGkMEuEOOkv7pkSo21mdqPpRZJm59SQX_ZGG1Br_v_iN-vWiA@mail.gmail.com>
Date: Mon, 22 Sep 2025 09:06:02 +0800
From: Jason Wang <jasowang@...hat.com>
To: "Michael S. Tsirkin" <mst@...hat.com>
Cc: xuanzhuo@...ux.alibaba.com, eperezma@...hat.com, 
	virtualization@...ts.linux.dev, linux-kernel@...r.kernel.org, 
	hch@...radead.org
Subject: Re: [PATCH V6 0/9] Refine virtio mapping API

On Mon, Sep 22, 2025 at 6:15 AM Michael S. Tsirkin <mst@...hat.com> wrote:
>
> On Thu, Aug 21, 2025 at 02:46:32PM +0800, Jason Wang wrote:
> > Hi all:
> >
> > Virtio used to be coupled with DMA API. This works fine for the device
> > that do real DMA but not the others. For example, VDUSE nees to craft
> > with DMA API in order to let the virtio-vdpa driver to work.
> >
> > This series tries to solve this issue by introducing the mapping API
> > in the virtio core. So transport like vDPA can implement their own
> > mapping logic without the need to hack with DMA API. The mapping API
> > are abstracted with a new map operations in order to be re-used by
> > transprot or device. So device like VDUSE can implement its own
> > mapping loigc.
> >
> > For device that uses DMA (for example PCI device), the virtio core
> > will still call DMA API directly without the need of implementing map
> > ops per device/transport.
> >
> > Please review.
>
> I sent some typos i found.
> Pls send fixups on top to fix them so testing in linux-next is not invalidated.
> Thanks!
>

Will do, I see the HEAD in linux-next is

vdpa: support virtio_map

Is this intended? Would you want me to send fixes on top?

Thanks

>
>
> > Changes since V5:
> >
> > - Rename mapping_token to virtio_map
> > - Do not use opaque void * pointer, just use a forward decalration of
> >   vduse_iova_domain
> > - Remove unused variable and typo fixes
> >
> > Changes since V4:
> >
> > - Rename map_token to mapping_token
> > - Introduce a union container for opaque token as well as the DMA
> >   device so we won't lose the type safety
> > - Do not try to set DMA mask for VDUSE device
> > - Introduce a new mapper_error op for API completeness
> >
> > Changes since V3:
> >
> > - Fix build error of PDS vDPA driver
> >
> > Changes since V2:
> >
> > - Drop VDUSE dependenct for HAS_DMA and ARCH_HAS_DMA_OPS
> >
> > Changes since V1:
> >
> > - Fix build error of mlx5_vdpa driver
> >
> >
> > Jason Wang (9):
> >   virtio_ring: constify virtqueue pointer for DMA helpers
> >   virtio_ring: switch to use dma_{map|unmap}_page()
> >   virtio: rename dma helpers
> >   virtio: introduce virtio_map container union
> >   virtio_ring: rename dma_handle to map_handle
> >   virtio: introduce map ops in virtio core
> >   vdpa: support virtio_map
> >   vdpa: introduce map ops
> >   vduse: switch to use virtio map API instead of DMA API
> >
> >  drivers/net/virtio_net.c                 |  28 +-
> >  drivers/vdpa/Kconfig                     |   8 +-
> >  drivers/vdpa/alibaba/eni_vdpa.c          |   5 +-
> >  drivers/vdpa/ifcvf/ifcvf_main.c          |   5 +-
> >  drivers/vdpa/mlx5/core/mr.c              |   4 +-
> >  drivers/vdpa/mlx5/net/mlx5_vnet.c        |  15 +-
> >  drivers/vdpa/octeon_ep/octep_vdpa_main.c |   6 +-
> >  drivers/vdpa/pds/vdpa_dev.c              |   5 +-
> >  drivers/vdpa/solidrun/snet_main.c        |   8 +-
> >  drivers/vdpa/vdpa.c                      |   5 +-
> >  drivers/vdpa/vdpa_sim/vdpa_sim.c         |   4 +-
> >  drivers/vdpa/vdpa_user/iova_domain.c     |   2 +-
> >  drivers/vdpa/vdpa_user/iova_domain.h     |   2 +-
> >  drivers/vdpa/vdpa_user/vduse_dev.c       |  79 ++--
> >  drivers/vdpa/virtio_pci/vp_vdpa.c        |   5 +-
> >  drivers/vhost/vdpa.c                     |   6 +-
> >  drivers/virtio/virtio_ring.c             | 459 ++++++++++++++---------
> >  drivers/virtio/virtio_vdpa.c             |  20 +-
> >  include/linux/vdpa.h                     |  25 +-
> >  include/linux/virtio.h                   |  46 ++-
> >  include/linux/virtio_config.h            |  72 ++++
> >  include/linux/virtio_ring.h              |   7 +-
> >  22 files changed, 531 insertions(+), 285 deletions(-)
> >
> > --
> > 2.31.1
>