From 83b5bd628f65e6b4d1924b307d6a88a57827bdb0 Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas@arm.com>
Date: Mon, 4 Jan 2021 12:36:14 +0000
Subject: [PATCH] arm64: Move PSTATE.TCO setting to separate functions

For consistency with __uaccess_{disable,enable}_hw_pan(), move the
PSTATE.TCO setting into dedicated __uaccess_{disable,enable}_tco()
functions.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 arch/arm64/include/asm/uaccess.h | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 6f986e09a7815..f0fe0cc6abe0b 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -176,10 +176,21 @@ static inline void __uaccess_enable_hw_pan(void)
  * The Tag check override (TCO) bit disables temporarily the tag checking
  * preventing the issue.
  */
-static inline void uaccess_disable_privileged(void)
+static inline void __uaccess_disable_tco(void)
 {
 	asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(0),
 				 ARM64_MTE, CONFIG_KASAN_HW_TAGS));
+}
+
+static inline void __uaccess_enable_tco(void)
+{
+	asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(1),
+				 ARM64_MTE, CONFIG_KASAN_HW_TAGS));
+}
+
+static inline void uaccess_disable_privileged(void)
+{
+	__uaccess_disable_tco();
 
 	if (uaccess_ttbr0_disable())
 		return;
@@ -189,8 +200,7 @@ static inline void uaccess_disable_privileged(void)
 
 static inline void uaccess_enable_privileged(void)
 {
-	asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(1),
-				 ARM64_MTE, CONFIG_KASAN_HW_TAGS));
+	__uaccess_enable_tco();
 
 	if (uaccess_ttbr0_enable())
 		return;
-- 
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