Revert "parisc: Add assembly implementations for memset, strlen, strcpy, strncpy and strcat"

This reverts commit 83af58f8

.

It turns out that at least the assembly implementation for strncpy() was
buggy.  Revert the whole commit and return back to the default coding.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/parisc/include/asm/string.h

@@ -8,19 +8,4 @@ extern void * memset(void *, int, size_t);
 #define __HAVE_ARCH_MEMCPY
 void * memcpy(void * dest,const void *src,size_t count);
 
-#define __HAVE_ARCH_STRLEN
-extern size_t strlen(const char *s);
-
-#define __HAVE_ARCH_STRCPY
-extern char *strcpy(char *dest, const char *src);
-
-#define __HAVE_ARCH_STRNCPY
-extern char *strncpy(char *dest, const char *src, size_t count);
-
-#define __HAVE_ARCH_STRCAT
-extern char *strcat(char *dest, const char *src);
-
-#define __HAVE_ARCH_MEMSET
-extern void *memset(void *, int, size_t);
-
 #endif

arch/parisc/kernel/parisc_ksyms.c

@@ -17,10 +17,6 @@
 
 #include <linux/string.h>
 EXPORT_SYMBOL(memset);
-EXPORT_SYMBOL(strlen);
-EXPORT_SYMBOL(strcpy);
-EXPORT_SYMBOL(strncpy);
-EXPORT_SYMBOL(strcat);
 
 #include <linux/atomic.h>
 EXPORT_SYMBOL(__xchg8);

arch/parisc/lib/Makefile

@@ -3,7 +3,7 @@
 # Makefile for parisc-specific library files
 #
 
-lib-y	:= lusercopy.o bitops.o checksum.o io.o memcpy.o \
-	   ucmpdi2.o delay.o string.o
+lib-y	:= lusercopy.o bitops.o checksum.o io.o memset.o memcpy.o \
+	   ucmpdi2.o delay.o
 
 obj-y	:= iomap.o

arch/parisc/lib/memset.c

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#include <linux/types.h>
+#include <asm/string.h>
+
+#define OPSIZ (BITS_PER_LONG/8)
+typedef unsigned long op_t;
+
+void *
+memset (void *dstpp, int sc, size_t len)
+{
+  unsigned int c = sc;
+  long int dstp = (long int) dstpp;
+
+  if (len >= 8)
+    {
+      size_t xlen;
+      op_t cccc;
+
+      cccc = (unsigned char) c;
+      cccc |= cccc << 8;
+      cccc |= cccc << 16;
+      if (OPSIZ > 4)
+	/* Do the shift in two steps to avoid warning if long has 32 bits.  */
+	cccc |= (cccc << 16) << 16;
+
+      /* There are at least some bytes to set.
+	 No need to test for LEN == 0 in this alignment loop.  */
+      while (dstp % OPSIZ != 0)
+	{
+	  ((unsigned char *) dstp)[0] = c;
+	  dstp += 1;
+	  len -= 1;
+	}
+
+      /* Write 8 `op_t' per iteration until less than 8 `op_t' remain.  */
+      xlen = len / (OPSIZ * 8);
+      while (xlen > 0)
+	{
+	  ((op_t *) dstp)[0] = cccc;
+	  ((op_t *) dstp)[1] = cccc;
+	  ((op_t *) dstp)[2] = cccc;
+	  ((op_t *) dstp)[3] = cccc;
+	  ((op_t *) dstp)[4] = cccc;
+	  ((op_t *) dstp)[5] = cccc;
+	  ((op_t *) dstp)[6] = cccc;
+	  ((op_t *) dstp)[7] = cccc;
+	  dstp += 8 * OPSIZ;
+	  xlen -= 1;
+	}
+      len %= OPSIZ * 8;
+
+      /* Write 1 `op_t' per iteration until less than OPSIZ bytes remain.  */
+      xlen = len / OPSIZ;
+      while (xlen > 0)
+	{
+	  ((op_t *) dstp)[0] = cccc;
+	  dstp += OPSIZ;
+	  xlen -= 1;
+	}
+      len %= OPSIZ;
+    }
+
+  /* Write the last few bytes.  */
+  while (len > 0)
+    {
+      ((unsigned char *) dstp)[0] = c;
+      dstp += 1;
+      len -= 1;
+    }
+
+  return dstpp;
+}

arch/parisc/lib/string.S

-// SPDX-License-Identifier: GPL-2.0
-/*
- *    PA-RISC assembly string functions
- *
- *    Copyright (C) 2019 Helge Deller <deller@gmx.de>
- */
-
-#include <asm/assembly.h>
-#include <linux/linkage.h>
-
-	.section .text.hot
-	.level PA_ASM_LEVEL
-
-	t0 = r20
-	t1 = r21
-	t2 = r22
-
-ENTRY_CFI(strlen, frame=0,no_calls)
-	or,COND(<>) arg0,r0,ret0
-	b,l,n	.Lstrlen_null_ptr,r0
-	depwi	0,31,2,ret0
-	cmpb,COND(<>) arg0,ret0,.Lstrlen_not_aligned
-	ldw,ma	4(ret0),t0
-	cmpib,tr 0,r0,.Lstrlen_loop
-	uxor,nbz r0,t0,r0
-.Lstrlen_not_aligned:
-	uaddcm	arg0,ret0,t1
-	shladd	t1,3,r0,t1
-	mtsar	t1
-	depwi	-1,%sar,32,t0
-	uxor,nbz r0,t0,r0
-.Lstrlen_loop:
-	b,l,n	.Lstrlen_end_loop,r0
-	ldw,ma	4(ret0),t0
-	cmpib,tr 0,r0,.Lstrlen_loop
-	uxor,nbz r0,t0,r0
-.Lstrlen_end_loop:
-	extrw,u,<> t0,7,8,r0
-	addib,tr,n -3,ret0,.Lstrlen_out
-	extrw,u,<> t0,15,8,r0
-	addib,tr,n -2,ret0,.Lstrlen_out
-	extrw,u,<> t0,23,8,r0
-	addi	-1,ret0,ret0
-.Lstrlen_out:
-	bv r0(rp)
-	uaddcm ret0,arg0,ret0
-.Lstrlen_null_ptr:
-	bv,n r0(rp)
-ENDPROC_CFI(strlen)
-
-
-ENTRY_CFI(strcpy, frame=0,no_calls)
-	ldb	0(arg1),t0
-	stb	t0,0(arg0)
-	ldo	0(arg0),ret0
-	ldo	1(arg1),t1
-	cmpb,=	r0,t0,2f
-	ldo	1(arg0),t2
-1:	ldb	0(t1),arg1
-	stb	arg1,0(t2)
-	ldo	1(t1),t1
-	cmpb,<> r0,arg1,1b
-	ldo	1(t2),t2
-2:	bv,n	r0(rp)
-ENDPROC_CFI(strcpy)
-
-
-ENTRY_CFI(strncpy, frame=0,no_calls)
-	ldb	0(arg1),t0
-	stb	t0,0(arg0)
-	ldo	1(arg1),t1
-	ldo	0(arg0),ret0
-	cmpb,=	r0,t0,2f
-	ldo	1(arg0),arg1
-1:	ldo	-1(arg2),arg2
-	cmpb,COND(=),n r0,arg2,2f
-	ldb	0(t1),arg0
-	stb	arg0,0(arg1)
-	ldo	1(t1),t1
-	cmpb,<> r0,arg0,1b
-	ldo	1(arg1),arg1
-2:	bv,n	r0(rp)
-ENDPROC_CFI(strncpy)
-
-
-ENTRY_CFI(strcat, frame=0,no_calls)
-	ldb	0(arg0),t0
-	cmpb,=	t0,r0,2f
-	ldo	0(arg0),ret0
-	ldo	1(arg0),arg0
-1:	ldb	0(arg0),t1
-	cmpb,<>,n r0,t1,1b
-	ldo	1(arg0),arg0
-2:	ldb	0(arg1),t2
-	stb	t2,0(arg0)
-	ldo	1(arg0),arg0
-	ldb	0(arg1),t0
-	cmpb,<>	r0,t0,2b
-	ldo	1(arg1),arg1
-	bv,n	r0(rp)
-ENDPROC_CFI(strcat)
-
-
-ENTRY_CFI(memset, frame=0,no_calls)
-	copy	arg0,ret0
-	cmpb,COND(=) r0,arg0,4f
-	copy	arg0,t2
-	cmpb,COND(=) r0,arg2,4f
-	ldo	-1(arg2),arg3
-	subi	-1,arg3,t0
-	subi	0,t0,t1
-	cmpiclr,COND(>=) 0,t1,arg2
-	ldo	-1(t1),arg2
-	extru arg2,31,2,arg0
-2:	stb	arg1,0(t2)
-	ldo	1(t2),t2
-	addib,>= -1,arg0,2b
-	ldo	-1(arg3),arg3
-	cmpiclr,COND(<=) 4,arg2,r0
-	b,l,n	4f,r0
-#ifdef CONFIG_64BIT
-	depd,*	r0,63,2,arg2
-#else
-	depw	r0,31,2,arg2
-#endif
-	ldo	1(t2),t2
-3:	stb	arg1,-1(t2)
-	stb	arg1,0(t2)
-	stb	arg1,1(t2)
-	stb	arg1,2(t2)
-	addib,COND(>) -4,arg2,3b
-	ldo	4(t2),t2
-4:	bv,n	r0(rp)
-ENDPROC_CFI(memset)
-
-	.end