If a system call takes a PROT_{NONE,EXEC,WRITE,...} argument,
this adds support to it to take a protection key.

        mmap()
        mrprotect()
        drivers/char/agp/frontend.c's ioctl(AGPIOC_RESERVE)

This does not include direct support for shmat() since it uses
a different set of permission bits.  You can use mprotect()
after the attach to assign an attched SHM segment a protection
key.

---

 b/arch/x86/include/uapi/asm/mman.h       |    6 ++++++
 b/include/uapi/asm-generic/mman-common.h |    4 ++++
 2 files changed, 10 insertions(+)

diff -puN arch/x86/include/uapi/asm/mman.h~pkeys-80-user-abi-bits 
arch/x86/include/uapi/asm/mman.h
--- a/arch/x86/include/uapi/asm/mman.h~pkeys-80-user-abi-bits   2015-09-16 
09:45:54.123412488 -0700
+++ b/arch/x86/include/uapi/asm/mman.h  2015-09-16 09:45:54.129412761 -0700
@@ -20,6 +20,12 @@
                ((vm_flags) & VM_PKEY_BIT1 ? _PAGE_PKEY_BIT1 : 0) |     \
                ((vm_flags) & VM_PKEY_BIT2 ? _PAGE_PKEY_BIT2 : 0) |     \
                ((vm_flags) & VM_PKEY_BIT3 ? _PAGE_PKEY_BIT3 : 0))
+
+#define arch_calc_vm_prot_bits(prot) ( \
+               ((prot) & PROT_PKEY0 ? VM_PKEY_BIT0 : 0) |      \
+               ((prot) & PROT_PKEY1 ? VM_PKEY_BIT1 : 0) |      \
+               ((prot) & PROT_PKEY2 ? VM_PKEY_BIT2 : 0) |      \
+               ((prot) & PROT_PKEY3 ? VM_PKEY_BIT3 : 0))
 #endif
 
 #include <asm-generic/mman.h>
diff -puN include/uapi/asm-generic/mman-common.h~pkeys-80-user-abi-bits 
include/uapi/asm-generic/mman-common.h
--- a/include/uapi/asm-generic/mman-common.h~pkeys-80-user-abi-bits     
2015-09-16 09:45:54.125412579 -0700
+++ b/include/uapi/asm-generic/mman-common.h    2015-09-16 09:45:54.128412715 
-0700
@@ -10,6 +10,10 @@
 #define PROT_WRITE     0x2             /* page can be written */
 #define PROT_EXEC      0x4             /* page can be executed */
 #define PROT_SEM       0x8             /* page may be used for atomic ops */
+#define PROT_PKEY0     0x10            /* protection key value (bit 0) */
+#define PROT_PKEY1     0x20            /* protection key value (bit 1) */
+#define PROT_PKEY2     0x40            /* protection key value (bit 2) */
+#define PROT_PKEY3     0x80            /* protection key value (bit 3) */
 #define PROT_NONE      0x0             /* page can not be accessed */
 #define PROT_GROWSDOWN 0x01000000      /* mprotect flag: extend change to 
start of growsdown vma */
 #define PROT_GROWSUP   0x02000000      /* mprotect flag: extend change to end 
of growsup vma */
_
--
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