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Message-ID: <a623049fb595480ffdf1130bbe800d79705cef03.camel@linux.ibm.com>
Subject: Re: [PATCH v4 4/7] s390/pci: Use dma-iommu layer
From:   Niklas Schnelle <schnelle@linux.ibm.com>
To:     Matthew Rosato <mjrosato@linux.ibm.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Wenjia Zhang <wenjia@linux.ibm.com>
Cc:     Gerd Bayer <gbayer@linux.ibm.com>,
        Pierre Morel <pmorel@linux.ibm.com>, iommu@lists.linux.dev,
        linux-s390@vger.kernel.org, borntraeger@linux.ibm.com,
        hca@linux.ibm.com, gor@linux.ibm.com,
        gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com,
        svens@linux.ibm.com, linux-kernel@vger.kernel.org,
        Julian Ruess <julianr@linux.ibm.com>
Date:   Thu, 19 Jan 2023 12:03:44 +0100
In-Reply-To: <71b9e85d-960f-7403-0113-135746127f3b@linux.ibm.com>
References: <20230104120543.308933-1-schnelle@linux.ibm.com>
         <20230104120543.308933-5-schnelle@linux.ibm.com>
         <71b9e85d-960f-7403-0113-135746127f3b@linux.ibm.com>
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> > > > > > > > > > > > > > > > =C2=A0
> > > > > > > > > > > > > > > >=20
> > > > > > > > > > > > > > > > =C2=A0static char *pci_sw_names[] =3D {
> > > > > > > > > > > > > > > > - "Allocated pages",
> > > > > > > > > > > > > > > > +/* TODO "Allocated pages", */
> > > > > > > >=20
> > > > > > > > ? Forgot to finish this?

Definitely forgot to remove the TODO. I think my latest plan was to
just remove this counter. With the DMA API conversion the
dma_map_ops.alloc and dma_map_ops.free move to common code and I don't
see how we could differentiate these from map/unmap on our side. I'm
not sure how helpful this counter really is either. If you're
interested in how many pages are mapped long term I think it makes more
sense to look at the difference between mapped and unmapped pages. What
do you think?
> > > > > > >=20