Merge branch 'for-next/asm' into for-next/core

* for-next/asm:
  arm64: uaccess: remove unnecessary earlyclobber
  arm64: uaccess: permit put_{user,kernel} to use zero register
  arm64: uaccess: permit __smp_store_release() to use zero register
  arm64: atomics: lse: improve cmpxchg implementation

Author: willdeacon

arch/arm64/include/asm/atomic_lse.h

@@ -251,22 +251,15 @@ __lse__cmpxchg_case_##name##sz(volatile void *ptr,			\
 					      u##sz old,		\
 					      u##sz new)		\
 {									\
-	register unsigned long x0 asm ("x0") = (unsigned long)ptr;	\
-	register u##sz x1 asm ("x1") = old;				\
-	register u##sz x2 asm ("x2") = new;				\
-	unsigned long tmp;						\
-									\
 	asm volatile(							\
 	__LSE_PREAMBLE							\
-	"	mov	%" #w "[tmp], %" #w "[old]\n"			\
-	"	cas" #mb #sfx "\t%" #w "[tmp], %" #w "[new], %[v]\n"	\
-	"	mov	%" #w "[ret], %" #w "[tmp]"			\
-	: [ret] "+r" (x0), [v] "+Q" (*(u##sz *)ptr),			\
-	  [tmp] "=&r" (tmp)						\
-	: [old] "r" (x1), [new] "r" (x2)				\
+	"	cas" #mb #sfx "	%" #w "[old], %" #w "[new], %[v]\n"	\
+	: [v] "+Q" (*(u##sz *)ptr),					\
+	  [old] "+r" (old)						\
+	: [new] "rZ" (new)						\
 	: cl);								\
 									\
-	return x0;							\
+	return old;							\
 }
 
 __CMPXCHG_CASE(w, b,     ,  8,   )

arch/arm64/include/asm/barrier.h

@@ -131,25 +131,25 @@ do {									\
 	case 1:								\
 		asm volatile ("stlrb %w1, %0"				\
 				: "=Q" (*__p)				\
-				: "r" (*(__u8 *)__u.__c)		\
+				: "rZ" (*(__u8 *)__u.__c)		\
 				: "memory");				\
 		break;							\
 	case 2:								\
 		asm volatile ("stlrh %w1, %0"				\
 				: "=Q" (*__p)				\
-				: "r" (*(__u16 *)__u.__c)		\
+				: "rZ" (*(__u16 *)__u.__c)		\
 				: "memory");				\
 		break;							\
 	case 4:								\
 		asm volatile ("stlr %w1, %0"				\
 				: "=Q" (*__p)				\
-				: "r" (*(__u32 *)__u.__c)		\
+				: "rZ" (*(__u32 *)__u.__c)		\
 				: "memory");				\
 		break;							\
 	case 8:								\
-		asm volatile ("stlr %1, %0"				\
+		asm volatile ("stlr %x1, %0"				\
 				: "=Q" (*__p)				\
-				: "r" (*(__u64 *)__u.__c)		\
+				: "rZ" (*(__u64 *)__u.__c)		\
 				: "memory");				\
 		break;							\
 	}								\

arch/arm64/include/asm/uaccess.h

@@ -237,7 +237,7 @@ static inline void __user *__uaccess_mask_ptr(const void __user *ptr)
 	"1:	" load "	" reg "1, [%2]\n"			\
 	"2:\n"								\
 	_ASM_EXTABLE_##type##ACCESS_ERR_ZERO(1b, 2b, %w0, %w1)		\
-	: "+r" (err), "=&r" (x)						\
+	: "+r" (err), "=r" (x)						\
 	: "r" (addr))
 
 #define __raw_get_mem(ldr, x, ptr, err, type)					\
@@ -327,7 +327,7 @@ do {									\
 	"2:\n"								\
 	_ASM_EXTABLE_##type##ACCESS_ERR(1b, 2b, %w0)			\
 	: "+r" (err)							\
-	: "r" (x), "r" (addr))
+	: "rZ" (x), "r" (addr))
 
 #define __raw_put_mem(str, x, ptr, err, type)					\
 do {										\