arm64: string: use asm EXPORT_SYMBOL()

For a while now it's been possible to use EXPORT_SYMBOL() in assembly
files, which allows us to place exports immediately after assembly
functions, as we do for C functions.

As a step towards removing arm64ksyms.c, let's move the string routine
exports to the assembly files the functions are defined in. Routines
which should only be exported for !KASAN builds are exported using the
EXPORT_SYMBOL_NOKASAN() helper.

There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/arm64ksyms.c

@@ -19,7 +19,6 @@
 
 #include <linux/export.h>
 #include <linux/sched.h>
-#include <linux/string.h>
 #include <linux/cryptohash.h>
 #include <linux/delay.h>
 #include <linux/in6.h>
@@ -29,25 +28,6 @@
 
 #include <asm/checksum.h>
 
-	/* string / mem functions */
-#ifndef CONFIG_KASAN
-EXPORT_SYMBOL(strchr);
-EXPORT_SYMBOL(strrchr);
-EXPORT_SYMBOL(strcmp);
-EXPORT_SYMBOL(strncmp);
-EXPORT_SYMBOL(strlen);
-EXPORT_SYMBOL(strnlen);
-EXPORT_SYMBOL(memcmp);
-EXPORT_SYMBOL(memchr);
-#endif
-
-EXPORT_SYMBOL(memset);
-EXPORT_SYMBOL(memcpy);
-EXPORT_SYMBOL(memmove);
-EXPORT_SYMBOL(__memset);
-EXPORT_SYMBOL(__memcpy);
-EXPORT_SYMBOL(__memmove);
-
 #ifdef CONFIG_FUNCTION_TRACER
 EXPORT_SYMBOL(_mcount);
 NOKPROBE_SYMBOL(_mcount);

arch/arm64/lib/memchr.S

@@ -42,3 +42,4 @@ WEAK(memchr)
 2:	mov	x0, #0
 	ret
 ENDPIPROC(memchr)
+EXPORT_SYMBOL_NOKASAN(memchr)

arch/arm64/lib/memcmp.S

@@ -256,3 +256,4 @@ CPU_LE( rev	data2, data2 )
 	mov	result, #0
 	ret
 ENDPIPROC(memcmp)
+EXPORT_SYMBOL_NOKASAN(memcmp)

arch/arm64/lib/memcpy.S

@@ -74,4 +74,6 @@ ENTRY(memcpy)
 #include "copy_template.S"
 	ret
 ENDPIPROC(memcpy)
+EXPORT_SYMBOL(memcpy)
 ENDPROC(__memcpy)
+EXPORT_SYMBOL(__memcpy)

arch/arm64/lib/memmove.S

@@ -197,4 +197,6 @@ ENTRY(memmove)
 	b.ne	.Ltail63
 	ret
 ENDPIPROC(memmove)
+EXPORT_SYMBOL(memmove)
 ENDPROC(__memmove)
+EXPORT_SYMBOL(__memmove)

arch/arm64/lib/memset.S

@@ -216,4 +216,6 @@ ENTRY(memset)
 	b.ne	.Ltail_maybe_long
 	ret
 ENDPIPROC(memset)
+EXPORT_SYMBOL(memset)
 ENDPROC(__memset)
+EXPORT_SYMBOL(__memset)

arch/arm64/lib/strchr.S

@@ -40,3 +40,4 @@ WEAK(strchr)
 	csel	x0, x0, xzr, eq
 	ret
 ENDPROC(strchr)
+EXPORT_SYMBOL_NOKASAN(strchr)

arch/arm64/lib/strcmp.S

@@ -232,3 +232,4 @@ CPU_BE(	orr	syndrome, diff, has_nul )
 	sub	result, data1, data2, lsr #56
 	ret
 ENDPIPROC(strcmp)
+EXPORT_SYMBOL_NOKASAN(strcmp)

arch/arm64/lib/strlen.S

@@ -124,3 +124,4 @@ CPU_LE( lsr	tmp2, tmp2, tmp1 )	/* Shift (tmp1 & 63).  */
 	csel	data2, data2, data2a, le
 	b	.Lrealigned
 ENDPIPROC(strlen)
+EXPORT_SYMBOL_NOKASAN(strlen)

arch/arm64/lib/strncmp.S

@@ -308,3 +308,4 @@ CPU_BE( orr	syndrome, diff, has_nul )
 	mov	result, #0
 	ret
 ENDPIPROC(strncmp)
+EXPORT_SYMBOL_NOKASAN(strncmp)

arch/arm64/lib/strnlen.S

@@ -169,3 +169,4 @@ CPU_LE( lsr	tmp2, tmp2, tmp4 )	/* Shift (tmp1 & 63).  */
 	mov	len, limit
 	ret
 ENDPIPROC(strnlen)
+EXPORT_SYMBOL_NOKASAN(strnlen)

arch/arm64/lib/strrchr.S

@@ -41,3 +41,4 @@ WEAK(strrchr)
 2:	mov	x0, x3
 	ret
 ENDPIPROC(strrchr)
+EXPORT_SYMBOL_NOKASAN(strrchr)