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

mainline inclusion
from mainline-5.10.62
commit 0085646e02b2423e20d0a9ea3fe64d8270255b23
bugzilla: 182217 https://gitee.com/openeuler/kernel/issues/I4EFOS

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0085646e02b2423e20d0a9ea3fe64d8270255b23

--------------------------------

commit f6a3308d upstream.

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: NHelge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org> # v5.4+
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

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