Re: [PATCH] s390/uaccess: introduce bit field for OAC specifier

[Heiko Carstens]

On Tue, Jan 11, 2022 at 11:00:03AM +0100, Janis Schoetterl-Glausch wrote:
> From: Nico Boehr <nrb@xxxxxxxxxxxxx>
> 
> Previously, we've used  magic values to specify the OAC
> (operand-access control) for mvcos.
> 
> Instead we introduce a bit field for it.
> 
> When using a bit field, we cannot use an immediate value with K
> constraint anymore, since GCC older than 10 doesn't recognize
> the bit field union as a compile time constant.
> To make things work with older compilers,
> load the OAC value through a register.
> 
> Bloat-o-meter reports a slight increase in kernel size with this change:
> Total: Before=15692135, After=15693015, chg +0.01%
> 
> Signed-off-by: Nico Boehr <nrb@xxxxxxxxxxxxx>
> Co-developed-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
> Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
> ---
>  arch/s390/include/asm/uaccess.h | 120 ++++++++++++++++++++------------
>  arch/s390/lib/uaccess.c         |  24 +++++--
>  2 files changed, 95 insertions(+), 49 deletions(-)

Applied with a couple of indentation + whitespace fixes.

Thanks!