[PATCH 06/25] powerpc: cleaup AMR,iAMR when a key is allocated or freed

[Ram Pai]

On Mon, Oct 23, 2017 at 03:13:45PM +0530, Aneesh Kumar K.V wrote:
> Balbir Singh <bsingharora at gmail.com> writes:
> 
> > On Fri,  8 Sep 2017 15:44:54 -0700
> > Ram Pai <linuxram at us.ibm.com> wrote:
> >
> >> cleanup the bits corresponding to a key in the AMR, and IAMR
> >> register, when the key is newly allocated/activated or is freed.
> >> We dont want some residual bits cause the hardware enforce
> >> unintended behavior when the key is activated or freed.
> >> 
> >> Signed-off-by: Ram Pai <linuxram at us.ibm.com>
> >> ---
> >>  arch/powerpc/include/asm/pkeys.h |   12 ++++++++++++
> >>  1 files changed, 12 insertions(+), 0 deletions(-)
> >> 
> >> diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
> >> index 5a83ed7..53bf13b 100644
> >> --- a/arch/powerpc/include/asm/pkeys.h
> >> +++ b/arch/powerpc/include/asm/pkeys.h
> >> @@ -54,6 +54,8 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
> >>  		mm_set_pkey_is_allocated(mm, pkey));
> >>  }
> >>  
> >> +extern void __arch_activate_pkey(int pkey);
> >> +extern void __arch_deactivate_pkey(int pkey);
> >>  /*
> >>   * Returns a positive, 5-bit key on success, or -1 on failure.
> >>   */
> >> @@ -80,6 +82,12 @@ static inline int mm_pkey_alloc(struct mm_struct *mm)
> >>  
> >>  	ret = ffz((u32)mm_pkey_allocation_map(mm));
> >>  	mm_set_pkey_allocated(mm, ret);
> >> +
> >> +	/*
> >> +	 * enable the key in the hardware
> >> +	 */
> >> +	if (ret > 0)
> >> +		__arch_activate_pkey(ret);
> >>  	return ret;
> >>  }
> >>  
> >> @@ -91,6 +99,10 @@ static inline int mm_pkey_free(struct mm_struct *mm, int pkey)
> >>  	if (!mm_pkey_is_allocated(mm, pkey))
> >>  		return -EINVAL;
> >>  
> >> +	/*
> >> +	 * Disable the key in the hardware
> >> +	 */
> >> +	__arch_deactivate_pkey(pkey);
> >>  	mm_set_pkey_free(mm, pkey);
> >>  
> >>  	return 0;
> >
> > I think some of these patches can be merged, too much fine granularity
> > is hurting my ability to see the larger function/implementation.
> 
> 
> Completely agree

Me agree too :) Had to fine-grain it to satisfy comments
received during the initial versions.  I had about 10-12 patches in total.

Thanks, will merge a couple of these patches.

RP