Re: [dpdk-dev] [PATCH v4 6/6] doc: deprecation notice for VFIO DMA map APIs

[David Marchand <david.marchand@redhat.com>]

On Wed, Oct 2, 2019 at 6:53 AM Shahaf Shuler <shahafs@mellanox.com> wrote:
>
> Hi David,
>
> Tuesday, October 1, 2019 6:20 PM, David Marchand:
> > Cc: dev@dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH v4 6/6] doc: deprecation notice for VFIO
> > DMA map APIs
> >
> > Hello Shahaf,
> >
> > On 10/03/2019 09:28, Shahaf Shuler wrote:
> > > As those should be replaced by rte_dev_dma_map and
> > rte_dev_dma_unmap
> > > APIs.
> > >
> > > Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
> > > ---
> > >  doc/guides/prog_guide/env_abstraction_layer.rst | 2 +-
> > >  doc/guides/rel_notes/deprecation.rst            | 4 ++++
> > >  2 files changed, 5 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst
> > > b/doc/guides/prog_guide/env_abstraction_layer.rst
> > > index 929d76dba7..ec2fe65523 100644
> > > --- a/doc/guides/prog_guide/env_abstraction_layer.rst
> > > +++ b/doc/guides/prog_guide/env_abstraction_layer.rst
> > > @@ -282,7 +282,7 @@ The expected workflow is as follows:
> > >      - If IOVA table is not specified, IOVA addresses will be assumed to be
> > >        unavailable
> > >      - Other processes must attach to the memory area before they can
> > > use it
> > > -* Perform DMA mapping with ``rte_vfio_dma_map`` if needed
> > > +* Perform DMA mapping with ``rte_dev_dma_map`` if needed
> > >  * Use the memory area in your application
> > >  * If memory area is no longer needed, it can be unregistered
> > >      - If the area was mapped for DMA, unmapping must be performed
> > > before diff --git a/doc/guides/rel_notes/deprecation.rst
> > > b/doc/guides/rel_notes/deprecation.rst
> > > index 1b4fcb7e64..48ec4fee88 100644
> > > --- a/doc/guides/rel_notes/deprecation.rst
> > > +++ b/doc/guides/rel_notes/deprecation.rst
> > > @@ -35,6 +35,10 @@ Deprecation Notices
> > >
> > >      + ``rte_eal_devargs_type_count``
> > >
> > > +* vfio: removal of ``rte_vfio_dma_map`` and ``rte_vfio_dma_unmap``
> > > +APIs which
> > > +  have been replaced with ``rte_dev_dma_map`` and
> > > +``rte_dev_dma_unmap``
> > > +  functions.  The due date for the removal targets DPDK 20.02.
> > > +
> > >  * pci: Several exposed functions are misnamed.
> > >    The following functions are deprecated starting from v17.11 and are
> > replaced:
> > >
> > >
> >
> > With the ABI freeze that is going to happen in 19.11, this can't happen in
> > 20.02.
> >
> > What would work best from your pov?
>
> I have no object (even prefer) to remove them at 19.11.
> At the time I sent the deprecation I was requested to provide more time for application to adopt.
>
> >
> > I can't see any in-tree user of rte_vfio_dma_*map, do you know of users of
> > this api?
>
> There is one - VPP. They don't use DPDK memory subsystem at all, rather use they own allocated memory and map all, wrongly, w/ above APIs.

Thanks Shahaf.

I cannot see VPP involved people copied in this thread.
It would have been great to involve them at the time.


Ray, can you reply on this topic (replacement of rte_vfio_dma_map) ?
Or could you serve as a gateway/copy the vpp guys?


Thanks.

--
David Marchand