Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers

[Ram Pai]

On Thu, Jul 27, 2017 at 05:40:44PM -0300, Thiago Jung Bauermann wrote:
> 
> Ram Pai  writes:
> 
> > Introduce helper functions that can initialize the bits in the AMR,
> > IAMR and UMOR register; the bits that correspond to the given pkey.
> >
> > Signed-off-by: Ram Pai 
> 
> s/UMOR/UAMOR/ here and in the subject as well.

yes. fixed it.

> 
> > --- a/arch/powerpc/mm/pkeys.c
> > +++ b/arch/powerpc/mm/pkeys.c
> > @@ -16,3 +16,47 @@
> >  #include /* PKEY_*   */
> >
> >  bool pkey_inited;
> > +#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
> > +
> > +static inline void init_amr(int pkey, u8 init_bits)
> > +{
> > +   u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> > +   u64 old_amr = read_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> > +
> > +   write_amr(old_amr | new_amr_bits);
> > +}
> > +
> > +static inline void init_iamr(int pkey, u8 init_bits)
> > +{
> > +   u64 new_iamr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> > +   u64 old_iamr = read_iamr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> > +
> > +   write_amr(old_iamr | new_iamr_bits);
> > +}
> 
> init_iamr should call write_iamr, not write_amr.

excellent catch. thanks.
RP

Re: [RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers

[Thiago Jung Bauermann]

Ram Pai  writes:

> Introduce helper functions that can initialize the bits in the AMR,
> IAMR and UMOR register; the bits that correspond to the given pkey.
>
> Signed-off-by: Ram Pai 

s/UMOR/UAMOR/ here and in the subject as well.

> --- a/arch/powerpc/mm/pkeys.c
> +++ b/arch/powerpc/mm/pkeys.c
> @@ -16,3 +16,47 @@
>  #include /* PKEY_*   */
>
>  bool pkey_inited;
> +#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
> +
> +static inline void init_amr(int pkey, u8 init_bits)
> +{
> + u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> + u64 old_amr = read_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> +
> + write_amr(old_amr | new_amr_bits);
> +}
> +
> +static inline void init_iamr(int pkey, u8 init_bits)
> +{
> + u64 new_iamr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
> + u64 old_iamr = read_iamr() & ~((u64)(0x3ul) << pkeyshift(pkey));
> +
> + write_amr(old_iamr | new_iamr_bits);
> +}

init_iamr should call write_iamr, not write_amr.

-- 
Thiago Jung Bauermann
IBM Linux Technology Center

[RFC v6 15/62] powerpc: helper functions to initialize AMR, IAMR and UMOR registers

[Ram Pai]

Introduce helper functions that can initialize the bits in the AMR,
IAMR and UMOR register; the bits that correspond to the given pkey.

Signed-off-by: Ram Pai 
---
 arch/powerpc/include/asm/pkeys.h |1 +
 arch/powerpc/mm/pkeys.c  |   44 ++
 2 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 09b268e..4327842 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -5,6 +5,7 @@
 #define arch_max_pkey()  32
 #define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
VM_PKEY_BIT3 | VM_PKEY_BIT4)
+#define AMR_BITS_PER_PKEY 2
 /*
  * Bits are in BE format.
  * NOTE: key 31, 1, 0 are not used.
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index c3acee1..04ee361 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -16,3 +16,47 @@
 #include /* PKEY_*   */
 
 bool pkey_inited;
+#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
+
+static inline void init_amr(int pkey, u8 init_bits)
+{
+   u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
+   u64 old_amr = read_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
+
+   write_amr(old_amr | new_amr_bits);
+}
+
+static inline void init_iamr(int pkey, u8 init_bits)
+{
+   u64 new_iamr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
+   u64 old_iamr = read_iamr() & ~((u64)(0x3ul) << pkeyshift(pkey));
+
+   write_amr(old_iamr | new_iamr_bits);
+}
+
+static void pkey_status_change(int pkey, bool enable)
+{
+   u64 old_uamor;
+
+   /* reset the AMR and IAMR bits for this key */
+   init_amr(pkey, 0x0);
+   init_iamr(pkey, 0x0);
+
+   /* enable/disable key */
+   old_uamor = read_uamor();
+   if (enable)
+   old_uamor |= (0x3ul << pkeyshift(pkey));
+   else
+   old_uamor &= ~(0x3ul << pkeyshift(pkey));
+   write_uamor(old_uamor);
+}
+
+void __arch_activate_pkey(int pkey)
+{
+   pkey_status_change(pkey, true);
+}
+
+void __arch_deactivate_pkey(int pkey)
+{
+   pkey_status_change(pkey, false);
+}
-- 
1.7.1