Subject: [RFC v7 11/25] powerpc: ability to associate pkey to a vma

From: Ram Pai <[email-masked]>
Date: Sun, 30 Jul 2017 17:12:12 -0700

arch-independent code expects the arch to  map
a  pkey  into the vma's protection bit setting.
The patch provides that ability.

Signed-off-by: Ram Pai <[email-masked]>
---
 arch/powerpc/include/asm/mman.h  |    8 +++++++-
 arch/powerpc/include/asm/pkeys.h |   12 ++++++++++++
 2 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
index 30922f6..067eec2 100644
--- a/arch/powerpc/include/asm/mman.h
+++ b/arch/powerpc/include/asm/mman.h
@@ -13,6 +13,7 @@
 
 #include <asm/cputable.h>
 #include <linux/mm.h>
+#include <linux/pkeys.h>
 #include <asm/cpu_has_feature.h>
 
 /*
@@ -22,7 +23,12 @@
 static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
 		unsigned long pkey)
 {
-	return (prot & PROT_SAO) ? VM_SAO : 0;
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+	return (((prot & PROT_SAO) ? VM_SAO : 0) |
+			pkey_to_vmflag_bits(pkey));
+#else
+	return ((prot & PROT_SAO) ? VM_SAO : 0);
+#endif
 }
 #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
 
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 5b17d93..a715a08 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -34,6 +34,18 @@
 				PKEY_DISABLE_WRITE  |\
 				PKEY_DISABLE_EXECUTE)
 
+static inline u64 pkey_to_vmflag_bits(u16 pkey)
+{
+	if (!pkey_inited)
+		return 0x0UL;
+
+	return (((pkey & 0x1UL) ? VM_PKEY_BIT0 : 0x0UL) |
+		((pkey & 0x2UL) ? VM_PKEY_BIT1 : 0x0UL) |
+		((pkey & 0x4UL) ? VM_PKEY_BIT2 : 0x0UL) |
+		((pkey & 0x8UL) ? VM_PKEY_BIT3 : 0x0UL) |
+		((pkey & 0x10UL) ? VM_PKEY_BIT4 : 0x0UL));
+}
+
 #define arch_max_pkey()  pkeys_total
 #define AMR_RD_BIT 0x1UL
 #define AMR_WR_BIT 0x2UL
-- 
1.7.1