On 15/05/18 15:16, Catalin Marinas wrote:
> Hi Jean-Philippe,
>
> On Fri, May 11, 2018 at 08:06:17PM +0100, Jean-Philippe Brucker wrote:
>> +unsigned long mm_context_get(struct mm_struct *mm)
>> +{
>> +unsigned long flags;
>> +u64 asid;
>> +
>> +raw_spin_lock_irqsave(&cpu_asid_lock, fl
Hi Jean-Philippe,
On Fri, May 11, 2018 at 08:06:17PM +0100, Jean-Philippe Brucker wrote:
> +unsigned long mm_context_get(struct mm_struct *mm)
> +{
> + unsigned long flags;
> + u64 asid;
> +
> + raw_spin_lock_irqsave(&cpu_asid_lock, flags);
> +
> + asid = atomic64_read(&mm->context
To enable address space sharing with the IOMMU, introduce mm_context_get()
and mm_context_put(), that pin down a context and ensure that it will keep
its ASID after a rollover.
Pinning is necessary because a device constantly needs a valid ASID,
unlike tasks that only require one when running. Wit
