Hi Jerome,
On Thu, Jul 03, 2014 at 02:30:26PM -0400, Jerome Glisse wrote:
> Joerg do you still object to this patch ?
Yes.
> Again the natural place to call this is from mmput and the fact that many
> other subsystem already call in from there to cleanup there own per mm data
> structure is a testimony that this is a valid use case and valid design.
Device drivers are something different than subsystems. I think the
point that the mmu_notifier struct can not be freed in the .release
call-back is a weak reason for introducing a new notifier. In the end
every user of mmu_notifiers has to call mmu_notifier_register somewhere
(file-open/ioctl path or somewhere else where the mm<->device binding is
set up) and can call mmu_notifier_unregister in a similar path which
destroys the binding.
> You pointed out that the cleanup should be done from the device driver file
> close call. But as i stressed some of the new user will not necessarily have
> a device file open hence no way for them to free the associated structure
> except with hackish delayed job.
Please tell me more about these 'new users', how does mm<->device binding
is set up there if no fd is used?
Joerg
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
