On 7/2/19 12:53 PM, Jason Gunthorpe wrote:
On Fri, Jun 07, 2019 at 05:14:52PM -0700, Ralph Campbell wrote:
HMM defines its own struct hmm_update which is passed to the
sync_cpu_device_pagetables() callback function. This is
sufficient when the only action is to invalidate. However,
a device may want to know the reason for the invalidation and
be able to see the new permissions on a range, update device access
rights or range statistics. Since sync_cpu_device_pagetables()
can be called from try_to_unmap(), the mmap_sem may not be held
and find_vma() is not safe to be called.
Pass the struct mmu_notifier_range to sync_cpu_device_pagetables()
to allow the full invalidation information to be used.
Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
---
I'm sending this out now since we are updating many of the HMM APIs
and I think it will be useful.
This make so much sense, I'd like to apply this in hmm.git, is there
any objection?
Jason
Not from me. :-)
Thanks!
