On Tue, Oct 13, 2020 at 10:46:16AM -0700, Dave Hansen wrote:
On 10/9/20 12:42 PM, ira.weiny@intel.com wrote:
Protection Keys User (PKU) and Protection Keys Supervisor (PKS) work in similar fashions and can share common defines.
Could we be a bit less abstract? PKS and PKU each have:
- A single control register
- The same number of keys
- The same number of bits in the register per key
- Access and Write disable in the same bit locations
That means that we can share all the macros that synthesize and manipulate register values between the two features.
Sure. Done.
+++ b/arch/x86/include/asm/pkeys_common.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_PKEYS_INTERNAL_H +#define _ASM_X86_PKEYS_INTERNAL_H
+#define PKR_AD_BIT 0x1 +#define PKR_WD_BIT 0x2 +#define PKR_BITS_PER_PKEY 2
+#define PKR_AD_KEY(pkey) (PKR_AD_BIT << ((pkey) * PKR_BITS_PER_PKEY))
Now that this has moved away from its use-site, it's a bit less self-documenting. Let's add a comment:
/*
- Generate an Access-Disable mask for the given pkey. Several of these
- can be OR'd together to generate pkey register values.
*/
Fair enough. done.
Once that's in place, along with the updated changelog:
Reviewed-by: Dave Hansen dave.hansen@linux.intel.com
Thanks, Ira