On Thu, 10 Oct 2013 14:54:29 -0600, Alex Williamson wrote:
> On Mon, 2013-10-07 at 10:58 +0900, Cho KyongHo wrote:
> > Patch written by Antonios Motakis <a.motakis@xxxxxxxxxxxxxxxxxxxxxx>:
> >
> > IOMMU groups are expected by certain users of the IOMMU API,
> > e.g. VFIO. Since each device is behind its own System MMU, we
> > can allocate a new IOMMU group for each device.
> >
> > Reviewd-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
> > Signed-off-by: Antonios Motakis <a.motakis@xxxxxxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/iommu/exynos-iommu.c | 28 ++++++++++++++++++++++++++++
> > 1 files changed, 28 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> > index 5025338..24505a0 100644
> > --- a/drivers/iommu/exynos-iommu.c
> > +++ b/drivers/iommu/exynos-iommu.c
> > @@ -1028,6 +1028,32 @@ static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *domain,
> > return phys;
> > }
> >
> > +static int exynos_iommu_add_device(struct device *dev)
> > +{
> > + struct iommu_group *group;
> > + int ret;
> > +
> > + group = iommu_group_get(dev);
>
> Seems reasonable, my only nit would be whether it's really an error to
> get a group back from the above call. If devices are always isolated
> and IOMMU groups are always singleton, it would be an error to find one
> already associated with the device. Right? Thanks,
>
Do you mean that calling iommu_group_add_device() with the group that is
returned by the above iommu_group_get() will return -EEXIST?
I didn't think about that.
> Alex
Thank you.
KyongHo.
>
> > +
> > + if (!group) {
> > + group = iommu_group_alloc();
> > + if (IS_ERR(group)) {
> > + dev_err(dev, "Failed to allocate IOMMU group\n");
> > + return PTR_ERR(group);
> > + }
> > + }
> > +
> > + ret = iommu_group_add_device(group, dev);
> > + iommu_group_put(group);
> > +
> > + return ret;
> > +}
> > +
> > +static void exynos_iommu_remove_device(struct device *dev)
> > +{
> > + iommu_group_remove_device(dev);
> > +}
> > +
> > static struct iommu_ops exynos_iommu_ops = {
> > .domain_init = &exynos_iommu_domain_init,
> > .domain_destroy = &exynos_iommu_domain_destroy,
> > @@ -1036,6 +1062,8 @@ static struct iommu_ops exynos_iommu_ops = {
> > .map = &exynos_iommu_map,
> > .unmap = &exynos_iommu_unmap,
> > .iova_to_phys = &exynos_iommu_iova_to_phys,
> > + .add_device = &exynos_iommu_add_device,
> > + .remove_device = &exynos_iommu_remove_device,
> > .pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
> > };
> >
>
>
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
