[RFC 02/12] mm: Generalize the mprotect implementation to support extensions

[Jarkko Sakkinen]

On Fri, 2018-09-07 at 15:34 -0700, Alison Schofield wrote:
> Today mprotect is implemented to support legacy mprotect behavior
> plus an extension for memory protection keys. Make it more generic
> so that it can support additional extensions in the future.
> 
> This is done is preparation for adding a new system call for memory
> encyption keys. The intent is that the new encrypted mprotect will be
> another extension to legacy mprotect.
> 
> Signed-off-by: Alison Schofield <alison.schofield at intel.com>
> ---
>  mm/mprotect.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/mprotect.c b/mm/mprotect.c
> index 68dc476310c0..56e64ef7931e 100644
> --- a/mm/mprotect.c
> +++ b/mm/mprotect.c
> @@ -35,6 +35,8 @@
>  
>  #include "internal.h"
>  
> +#define NO_PKEY  -1

This commit does not make anything more generic but it does take
away a magic number. The code change is senseful. The commit
message is nonsense.

PS. Please use @linux.intel.com for LKML.

/Jarkko