Messages in this thread | | | Date | Wed, 13 May 2020 12:45:37 +0200 | From | Jean-Philippe Brucker <> | Subject | Re: [EXT] Re: [PATCH v5] iommu/virtio: Use page size bitmap supported by endpoint |
| |
On Wed, May 13, 2020 at 09:15:22AM +0000, Bharat Bhushan wrote: > Hi Jean, > > > -----Original Message----- > > From: Michael S. Tsirkin <mst@redhat.com> > > Sent: Wednesday, May 6, 2020 5:53 AM > > To: Bharat Bhushan <bbhushan2@marvell.com> > > Cc: jean-philippe@linaro.org; joro@8bytes.org; jasowang@redhat.com; > > virtualization@lists.linux-foundation.org; iommu@lists.linux-foundation.org; > > linux-kernel@vger.kernel.org; eric.auger.pro@gmail.com; eric.auger@redhat.com > > Subject: [EXT] Re: [PATCH v5] iommu/virtio: Use page size bitmap supported by > > endpoint [...] > > > +struct virtio_iommu_probe_pgsize_mask { > > > + struct virtio_iommu_probe_property head; > > > + __u8 reserved[4]; > > > + __le64 pgsize_bitmap; > > > +}; > > > + > > > > This is UAPI. Document the format of pgsize_bitmap please. > > I do not see uapi documentation in "Documentation" folder of other data struct in this file, am I missing something?
I'm not the one requesting this change, but I'm guessing you should add a comment in this header, above pgsize_bitmap (which should actually be called page_size_mask to follow the spec). I guess I'd add:
/* Same format as virtio_iommu_config::page_size_mask */
for this field, and then maybe change the comment of virtio_iommu_config, currently "/* Supported page sizes */", to something more precise such as:
/* * Bitmap of supported page sizes. The least significant bit indicates the * smallest granularity and the other bits are hints indicating optimal * block sizes. */
But I don't know how much should be spelled out here, since those details are available in the spec.
Thanks, Jean
| |