From 482b9b3948675df60c015b2155011c1f93234992 Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Date: Thu, 9 Jul 2020 08:59:46 +0530
Subject: [PATCH] powerpc/book3s64/pkeys: Remove is_pkey_enabled()

References: jsc#SLE-16556 bsc#1078248 FATE#322447
Patch-mainline: v5.9-rc1
Git-commit: 482b9b3948675df60c015b2155011c1f93234992

There is only one caller to this function and the function is wrongly
named. Avoid further confusion w.r.t name and open code this at the
only call site. Also remove read_uamor(). There are no users for
the same after this.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-24-aneesh.kumar@linux.ibm.com
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/mm/book3s64/pkeys.c | 31 +++++++++++--------------------
 1 file changed, 11 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index d45864a77066..792b36aa9619 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -251,25 +251,6 @@ static inline void write_iamr(u64 value)
 	mtspr(SPRN_IAMR, value);
 }
 
-static inline u64 read_uamor(void)
-{
-	return mfspr(SPRN_UAMOR);
-}
-
-static bool is_pkey_enabled(int pkey)
-{
-	u64 uamor = read_uamor();
-	u64 pkey_bits = 0x3ul << pkeyshift(pkey);
-	u64 uamor_pkey_bits = (uamor & pkey_bits);
-
-	/*
-	 * Both the bits in UAMOR corresponding to the key should be set or
-	 * reset.
-	 */
-	WARN_ON(uamor_pkey_bits && (uamor_pkey_bits != pkey_bits));
-	return !!(uamor_pkey_bits);
-}
-
 static inline void init_amr(int pkey, u8 init_bits)
 {
 	u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
@@ -295,8 +276,18 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
 {
 	u64 new_amr_bits = 0x0ul;
 	u64 new_iamr_bits = 0x0ul;
+	u64 pkey_bits, uamor_pkey_bits;
 
-	if (!is_pkey_enabled(pkey))
+	/*
+	 * Check whether the key is disabled by UAMOR.
+	 */
+	pkey_bits = 0x3ul << pkeyshift(pkey);
+	uamor_pkey_bits = (default_uamor & pkey_bits);
+
+	/*
+	 * Both the bits in UAMOR corresponding to the key should be set
+	 */
+	if (uamor_pkey_bits != pkey_bits)
 		return -EINVAL;
 
 	if (init_val & PKEY_DISABLE_EXECUTE) {
-- 
2.26.2