Re: [PATCH RFC 0/3] MAP_POPULATE for device memory

David Hildenbrand
2022-03-07T10:12:50Z

On 06.03.22 06:32, Jarkko Sakkinen wrote:
> For device memory (aka VM_IO | VM_PFNMAP) MAP_POPULATE does nothing. Allow
> to use that for initializing the device memory by providing a new callback
> f_ops->populate() for the purpose.
>
> SGX patches are provided to show the callback in context.
>
> An obvious alternative is a ioctl but it is less elegant and requires
> two syscalls (mmap + ioctl) per memory range, instead of just one
> (mmap).

What about extending MADV_POPULATE_READ | MADV_POPULATE_WRITE to support
VM_IO | VM_PFNMAP (as well?) ?

--
Thanks,

David / dhildenb