Subject: [PATCH v9 05/51] powerpc: helper function to read, write AMR, IAMR, UAMOR registers

From: Ram Pai <[email-masked]>
Date: Mon, 6 Nov 2017 00:56:57 -0800

Implements helper functions to read and write the key related
registers; AMR, IAMR, UAMOR.

AMR register tracks the read,write permission of a key
IAMR register tracks the execute permission of a key
UAMOR register enables and disables a key

Acked-by: Balbir Singh <[email-masked]>
Reviewed-by: Thiago Jung Bauermann <[email-masked]>
Signed-off-by: Ram Pai <[email-masked]>
---
 arch/powerpc/mm/pkeys.c |   36 ++++++++++++++++++++++++++++++++++++
 1 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index 512bdf2..b6bdfdf 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -61,3 +61,39 @@ void __init pkey_initialize(void)
 	for (i = 2; i < (pkeys_total - os_reserved); i++)
 		initial_allocation_mask &= ~(0x1 << i);
 }
+
+static inline u64 read_amr(void)
+{
+	return mfspr(SPRN_AMR);
+}
+
+static inline void write_amr(u64 value)
+{
+	mtspr(SPRN_AMR, value);
+}
+
+static inline u64 read_iamr(void)
+{
+	if (!likely(pkey_execute_disable_supported))
+		return 0x0UL;
+
+	return mfspr(SPRN_IAMR);
+}
+
+static inline void write_iamr(u64 value)
+{
+	if (!likely(pkey_execute_disable_supported))
+		return;
+
+	mtspr(SPRN_IAMR, value);
+}
+
+static inline u64 read_uamor(void)
+{
+	return mfspr(SPRN_UAMOR);
+}
+
+static inline void write_uamor(u64 value)
+{
+	mtspr(SPRN_UAMOR, value);
+}
-- 
1.7.1