Re: kmap() transformation: Question about copy_user_highpage

[Huacai Chen]

Hi, Deepak,

On Sat, Oct 7, 2023 at 2:46 AM Deepak R Varma <drv@xxxxxxxxx> wrote:
>
> Hello,
> I am attempting to work on replacing the kmap[_atomic]() calls by
> kmap_local_page() function call. A detail on this change can be found here [0].
>
> I would like to know if this function:
>         arch/loongarch/mm/init.c::copy_user_highpage()
> is currently in use or is it a dead code?
>
> If this code is not in use, can this be removed instead? However, if it is in
> use, can you comment why kmap_atomic() was preferred over kmap()
> function call?
I think this function will be used for the 32bit kernel, and we will
add loongarch32 support in the near future.

But on the other hand, you can replace kmap_atomic() with
kmap_local_page(), there is no special reason to use kmap_atomic().

Huacai

>
> [0] https://lore.kernel.org/all/20201029222652.302358281@xxxxxxxxxxxxx/
>
> Thank you,
> Deepak.
>
>
>