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: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: NMark Rutland <mark.rutland@arm.com>

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;