Re: [PATCH v3 12/20] RDMA/rw: use dma_map_sgtable()

[Max Gurtovoy]

On 9/28/2021 10:43 PM, Jason Gunthorpe wrote:
> On Thu, Sep 16, 2021 at 05:40:52PM -0600, Logan Gunthorpe wrote:
> > dma_map_sg() now supports the use of P2PDMA pages so pci_p2pdma_map_sg()
> > is no longer necessary and may be dropped.
> >
> > Switch to the dma_map_sgtable() interface which will allow for better
> > error reporting if the P2PDMA pages are unsupported.
> >
> > The change to sgtable also appears to fix a couple subtle error path
> > bugs:
> >
> >    - In rdma_rw_ctx_init(), dma_unmap would be called with an sg
> >      that could have been incremented from the original call, as
> >      well as an nents that was not the original number of nents
> >      called when mapped.
> >    - Similarly in rdma_rw_ctx_signature_init, both sg and prot_sg
> >      were unmapped with the incorrect number of nents.
> Those bugs should definately get fixed.. I might extract the sgtable
> conversion into a stand alone patch to do it.

Yes, we need these fixes before this series will converge.

Looks good,

Reviewed-by: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>

> But as it is, this looks fine
>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
>
> Jason