[GIT PULL] iommu: Kill off pgsize_bitmap field from struct iommu_ops

David Woodhouse dwmw2 at infradead.org
Wed Apr 1 06:52:57 PDT 2015


On Wed, 2015-04-01 at 14:39 +0100, Will Deacon wrote:
> We'd also need to update any page-table code that relies on being called
> one page at a time (i.e. the new io-pgtable stuff we merged for 4.0) so
> that we iterate over the requested range.

Ick. I hadn't noticed we'd entrenched that mistake even harder. It
certainly *wasn't* that hard to fix it...

>  That shouldn't be too difficult (i.e. just inline the iommu_map logic
> into each driver), but it would need some testing.

Good.

> In fact, that would also allow us to nuke the whole TLB on VFIO unmap of
> large ranges. We currently iterate over the range page-by-page, which takes
> ages (minutes) in simulation.

Which is one of the big reasons we lie about page sizes in VT-d.

-- 
dwmw2

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