lkml.org 
[lkml]   [2022]   [Jan]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRE: [PATCH 7/7] iommu: Add iommu_domain::domain_ops
    Date
    > From: Jason Gunthorpe via iommu
    > Sent: Tuesday, January 25, 2022 1:18 AM
    >
    > On Mon, Jan 24, 2022 at 09:58:18AM +0000, Tian, Kevin wrote:
    > > > From: Lu Baolu <baolu.lu@linux.intel.com>
    > > > Sent: Monday, January 24, 2022 3:11 PM
    > > > +/**
    > > > + * struct domain_ops - per-domain ops
    > > > + * @attach_dev: attach an iommu domain to a device
    > > > + * @detach_dev: detach an iommu domain from a device
    > >
    > > What is the criteria about whether an op should be iommu_ops or
    > domain_ops
    > > when it requires both domain and device pointers like above two (and
    > future
    > > PASID-based attach)?
    > >
    > > Other examples include:
    > > @apply_resv_region
    >
    > For apply_resv_region the 'dev' argument is really selecting a device
    > that is already attached to the domain, so it should be in the domain
    > ops.

    Looks this one can be just removed. No iommu driver implements today.

    >
    > > @is_attach_deferred
    >
    > Only two drivers implement this and neither use the domain
    > argument. Remove the domain argument and keep it in the iommu_ops
    >

    Yes, especially when none of the two drivers actually uses domain.

    Generally it makes sense to me by putting all attach related callbacks in
    iommu_ops, since they are all for building connections between device
    and domain while such connection is device specific (just like how a
    vfio device is connected to iommufd).

    This in concept also applies to @enable_nesting which you mentioned
    in another thread. Nesting is a per-device configuration between multiple
    domains attached by a same device.

    Thanks
    Kevin

    \
     
     \ /
      Last update: 2022-01-25 04:39    [W:8.435 / U:0.092 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site