s390/kasan: remove override of mem*() functions

The kasan mem*() functions are not used anymore since s390 has switched
to GENERIC_ENTRY and commit 69d4c0d ("entry, kasan, x86: Disallow
overriding mem*() functions").

Therefore remove the now dead code, similar to x86.
While at it also use the SYM* macros in mem.S.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Author: hcahca

arch/s390/include/asm/string.h

@@ -55,18 +55,6 @@ char *strstr(const char *s1, const char *s2);
 
 #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
 
-extern void *__memcpy(void *dest, const void *src, size_t n);
-extern void *__memset(void *s, int c, size_t n);
-extern void *__memmove(void *dest, const void *src, size_t n);
-
-/*
- * For files that are not instrumented (e.g. mm/slub.c) we
- * should use not instrumented version of mem* functions.
- */
-
-#define memcpy(dst, src, len) __memcpy(dst, src, len)
-#define memmove(dst, src, len) __memmove(dst, src, len)
-#define memset(s, c, n) __memset(s, c, n)
 #define strlen(s) __strlen(s)
 
 #define __no_sanitize_prefix_strfunc(x) __##x
@@ -79,6 +67,9 @@ extern void *__memmove(void *dest, const void *src, size_t n);
 #define __no_sanitize_prefix_strfunc(x) x
 #endif /* defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) */
 
+void *__memcpy(void *dest, const void *src, size_t n);
+void *__memset(void *s, int c, size_t n);
+void *__memmove(void *dest, const void *src, size_t n);
 void *__memset16(uint16_t *s, uint16_t v, size_t count);
 void *__memset32(uint32_t *s, uint32_t v, size_t count);
 void *__memset64(uint64_t *s, uint64_t v, size_t count);

arch/s390/lib/mem.S

@@ -14,8 +14,7 @@
 /*
  * void *memmove(void *dest, const void *src, size_t n)
  */
-WEAK(memmove)
-ENTRY(__memmove)
+SYM_FUNC_START(__memmove)
 	ltgr	%r4,%r4
 	lgr	%r1,%r2
 	jz	.Lmemmove_exit
@@ -48,7 +47,10 @@ ENTRY(__memmove)
 	BR_EX	%r14
 .Lmemmove_mvc:
 	mvc	0(1,%r1),0(%r3)
-ENDPROC(__memmove)
+SYM_FUNC_END(__memmove)
+EXPORT_SYMBOL(__memmove)
+
+SYM_FUNC_ALIAS(memmove, __memmove)
 EXPORT_SYMBOL(memmove)
 
 /*
@@ -66,8 +68,7 @@ EXPORT_SYMBOL(memmove)
  *	return __builtin_memset(s, c, n);
  * }
  */
-WEAK(memset)
-ENTRY(__memset)
+SYM_FUNC_START(__memset)
 	ltgr	%r4,%r4
 	jz	.Lmemset_exit
 	ltgr	%r3,%r3
@@ -111,16 +112,18 @@ ENTRY(__memset)
 	xc	0(1,%r1),0(%r1)
 .Lmemset_mvc:
 	mvc	1(1,%r1),0(%r1)
-ENDPROC(__memset)
+SYM_FUNC_END(__memset)
+EXPORT_SYMBOL(__memset)
+
+SYM_FUNC_ALIAS(memset, __memset)
 EXPORT_SYMBOL(memset)
 
 /*
  * memcpy implementation
  *
  * void *memcpy(void *dest, const void *src, size_t n)
  */
-WEAK(memcpy)
-ENTRY(__memcpy)
+SYM_FUNC_START(__memcpy)
 	ltgr	%r4,%r4
 	jz	.Lmemcpy_exit
 	aghi	%r4,-1
@@ -141,7 +144,10 @@ ENTRY(__memcpy)
 	j	.Lmemcpy_remainder
 .Lmemcpy_mvc:
 	mvc	0(1,%r1),0(%r3)
-ENDPROC(__memcpy)
+SYM_FUNC_END(__memcpy)
+EXPORT_SYMBOL(__memcpy)
+
+SYM_FUNC_ALIAS(memcpy, __memcpy)
 EXPORT_SYMBOL(memcpy)
 
 /*