powerpc: fix __strnlen_user in merge tree

Change USER/KERNEL_DS so that the merged version of
__strnlen_user can be used which allows us to complete the
removal of arch/ppc64/lib/.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

arch/powerpc/lib/Makefile

@@ -9,7 +9,7 @@ endif
 obj-y			+= strcase.o
 obj-$(CONFIG_PPC32)	+= div64.o copy_32.o checksum_32.o
 obj-$(CONFIG_PPC64)	+= checksum_64.o copypage_64.o copyuser_64.o \
-			   memcpy_64.o usercopy_64.o mem_64.o
+			   memcpy_64.o usercopy_64.o mem_64.o string.o
 obj-$(CONFIG_PPC_ISERIES) += e2a.o
 obj-$(CONFIG_XMON)	+= sstep.o
 

arch/ppc64/Makefile

@@ -86,7 +86,6 @@ head-y := arch/ppc64/kernel/head.o
 head-y += arch/powerpc/kernel/fpu.o
 head-y += arch/powerpc/kernel/entry_64.o
 
-libs-y				+= arch/ppc64/lib/
 core-y				+= arch/ppc64/kernel/ arch/powerpc/kernel/
 core-y				+= arch/powerpc/mm/
 core-y				+= arch/powerpc/sysdev/

arch/ppc64/lib/Makefile

-#
-# Makefile for ppc64-specific library files..
-#
-
-lib-y := string.o

arch/ppc64/lib/string.S

-/*
- * String handling functions for PowerPC.
- *
- * Copyright (C) 1996 Paul Mackerras.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-#include <asm/processor.h>
-#include <asm/errno.h>
-#include <asm/ppc_asm.h>
-
-_GLOBAL(strcpy)
-	addi	r5,r3,-1
-	addi	r4,r4,-1
-1:	lbzu	r0,1(r4)
-	cmpwi	0,r0,0
-	stbu	r0,1(r5)
-	bne	1b
-	blr
-
-_GLOBAL(strncpy)
-	cmpwi	0,r5,0
-	beqlr
-	mtctr	r5
-	addi	r6,r3,-1
-	addi	r4,r4,-1
-1:	lbzu	r0,1(r4)
-	cmpwi	0,r0,0
-	stbu	r0,1(r6)
-	bdnzf	2,1b		/* dec ctr, branch if ctr != 0 && !cr0.eq */
-	blr
-
-_GLOBAL(strcat)
-	addi	r5,r3,-1
-	addi	r4,r4,-1
-1:	lbzu	r0,1(r5)
-	cmpwi	0,r0,0
-	bne	1b
-	addi	r5,r5,-1
-1:	lbzu	r0,1(r4)
-	cmpwi	0,r0,0
-	stbu	r0,1(r5)
-	bne	1b
-	blr
-
-_GLOBAL(strcmp)
-	addi	r5,r3,-1
-	addi	r4,r4,-1
-1:	lbzu	r3,1(r5)
-	cmpwi	1,r3,0
-	lbzu	r0,1(r4)
-	subf.	r3,r0,r3
-	beqlr	1
-	beq	1b
-	blr
-
-_GLOBAL(strlen)
-	addi	r4,r3,-1
-1:	lbzu	r0,1(r4)
-	cmpwi	0,r0,0
-	bne	1b
-	subf	r3,r3,r4
-	blr
-
-_GLOBAL(memcmp)
-	cmpwi	0,r5,0
-	ble-	2f
-	mtctr	r5
-	addi	r6,r3,-1
-	addi	r4,r4,-1
-1:	lbzu	r3,1(r6)
-	lbzu	r0,1(r4)
-	subf.	r3,r0,r3
-	bdnzt	2,1b
-	blr
-2:	li	r3,0
-	blr
-
-_GLOBAL(memchr)
-	cmpwi	0,r5,0
-	ble-	2f
-	mtctr	r5
-	addi	r3,r3,-1
-1:	lbzu	r0,1(r3)
-	cmpw	0,r0,r4
-	bdnzf	2,1b
-	beqlr
-2:	li	r3,0
-	blr
-
-_GLOBAL(__clear_user)
-	addi	r6,r3,-4
-	li	r3,0
-	li	r5,0
-	cmplwi	0,r4,4
-	blt	7f
-	/* clear a single word */
-11:	stwu	r5,4(r6)
-	beqlr
-	/* clear word sized chunks */
-	andi.	r0,r6,3
-	add	r4,r0,r4
-	subf	r6,r0,r6
-	srwi	r0,r4,2
-	andi.	r4,r4,3
-	mtctr	r0
-	bdz	7f
-1:	stwu	r5,4(r6)
-	bdnz	1b
-	/* clear byte sized chunks */
-7:	cmpwi	0,r4,0
-	beqlr
-	mtctr	r4
-	addi	r6,r6,3
-8:	stbu	r5,1(r6)
-	bdnz	8b
-	blr
-90:	mr	r3,r4
-	blr
-91:	mfctr	r3
-	slwi	r3,r3,2
-	add	r3,r3,r4
-	blr
-92:	mfctr	r3
-	blr
-
-	.section __ex_table,"a"
-	.align	3
-	.llong	11b,90b
-	.llong	1b,91b
-	.llong	8b,92b
-	.text
-
-/* r3 = dst, r4 = src, r5 = count */
-_GLOBAL(__strncpy_from_user)
-	addi	r6,r3,-1
-	addi	r4,r4,-1
-	cmpwi	0,r5,0
-	beq	2f
-	mtctr	r5
-1:	lbzu	r0,1(r4)
-	cmpwi	0,r0,0
-	stbu	r0,1(r6)
-	bdnzf	2,1b		/* dec ctr, branch if ctr != 0 && !cr0.eq */
-	beq	3f
-2:	addi	r6,r6,1
-3:	subf	r3,r3,r6
-	blr
-99:	li	r3,-EFAULT
-	blr
-
-	.section __ex_table,"a"
-	.align	3
-	.llong	1b,99b
-	.text
-
-/* r3 = str, r4 = len (> 0) */
-_GLOBAL(__strnlen_user)
-	addi	r7,r3,-1
-	mtctr	r4		/* ctr = len */
-1:	lbzu	r0,1(r7)	/* get next byte */
-	cmpwi	0,r0,0
-	bdnzf	2,1b		/* loop if --ctr != 0 && byte != 0 */
-	addi	r7,r7,1
-	subf	r3,r3,r7	/* number of bytes we have looked at */
-	beqlr			/* return if we found a 0 byte */
-	cmpw	0,r3,r4		/* did we look at all len bytes? */
-	blt	99f		/* if not, must have hit top */
-	addi	r3,r4,1		/* return len + 1 to indicate no null found */
-	blr
-99:	li	r3,0		/* bad address, return 0 */
-	blr
-
-	.section __ex_table,"a"
-	.align	3
-	.llong	1b,99b

include/asm-powerpc/uaccess.h

@@ -24,11 +24,11 @@
 
 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
 
+#define KERNEL_DS	MAKE_MM_SEG(~0UL)
 #ifdef __powerpc64__
-#define KERNEL_DS	MAKE_MM_SEG(0UL)
-#define USER_DS		MAKE_MM_SEG(0xf000000000000000UL)
+/* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */
+#define USER_DS		MAKE_MM_SEG(TASK_SIZE_USER64 - 1)
 #else
-#define KERNEL_DS	MAKE_MM_SEG(~0UL)
 #define USER_DS		MAKE_MM_SEG(TASK_SIZE - 1)
 #endif
 
@@ -40,22 +40,11 @@
 
 #ifdef __powerpc64__
 /*
- * Use the alpha trick for checking ranges:
- *
- * Is a address valid? This does a straightforward calculation rather
- * than tests.
- *
- * Address valid if:
- *  - "addr" doesn't have any high-bits set
- *  - AND "size" doesn't have any high-bits set
- *  - OR we are in kernel mode.
- *
- * We dont have to check for high bits in (addr+size) because the first
- * two checks force the maximum result to be below the start of the
- * kernel region.
+ * This check is sufficient because there is a large enough
+ * gap between user addresses and the kernel addresses
  */
 #define __access_ok(addr, size, segment)	\
-	(((segment).seg & (addr | size )) == 0)
+	(((addr) <= (segment).seg) && ((size) <= (segment).seg))
 
 #else
 
@@ -161,7 +150,10 @@ extern long __put_user_bad(void);
 		: "=r" (err)					\
 		: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
 
-#ifndef __powerpc64__
+#ifdef __powerpc64__
+#define __put_user_asm2(x, ptr, retval)				\
+	  __put_user_asm(x, ptr, retval, "std")
+#else /* __powerpc64__ */
 #define __put_user_asm2(x, addr, err)				\
 	__asm__ __volatile__(					\
 		"1:	stw %1,0(%2)\n"				\
@@ -178,9 +170,6 @@ extern long __put_user_bad(void);
 		".previous"					\
 		: "=r" (err)					\
 		: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
-#else /* __powerpc64__ */
-#define __put_user_asm2(x, ptr, retval)				\
-	  __put_user_asm(x, ptr, retval, "std")
 #endif /* __powerpc64__ */
 
 #define __put_user_size(x, ptr, size, retval)			\
@@ -232,7 +221,10 @@ extern long __get_user_bad(void);
 		: "=r" (err), "=r" (x)			\
 		: "b" (addr), "i" (-EFAULT), "0" (err))
 
-#ifndef __powerpc64__
+#ifdef __powerpc64__
+#define __get_user_asm2(x, addr, err)			\
+	__get_user_asm(x, addr, err, "ld")
+#else /* __powerpc64__ */
 #define __get_user_asm2(x, addr, err)			\
 	__asm__ __volatile__(				\
 		"1:	lwz %1,0(%2)\n"			\
@@ -251,9 +243,6 @@ extern long __get_user_bad(void);
 		".previous"				\
 		: "=r" (err), "=&r" (x)			\
 		: "b" (addr), "i" (-EFAULT), "0" (err))
-#else
-#define __get_user_asm2(x, addr, err)	 		\
-	__get_user_asm(x, addr, err, "ld")
 #endif /* __powerpc64__ */
 
 #define __get_user_size(x, ptr, size, retval)			\
@@ -313,8 +302,9 @@ extern unsigned long __copy_tofrom_user(void __user *to,
 		const void __user *from, unsigned long size);
 
 #ifndef __powerpc64__
-extern inline unsigned long
-copy_from_user(void *to, const void __user *from, unsigned long n)
+
+extern inline unsigned long copy_from_user(void *to,
+		const void __user *from, unsigned long n)
 {
 	unsigned long over;
 
@@ -328,8 +318,8 @@ copy_from_user(void *to, const void __user *from, unsigned long n)
 	return n;
 }
 
-extern inline unsigned long
-copy_to_user(void __user *to, const void *from, unsigned long n)
+extern inline unsigned long copy_to_user(void __user *to,
+		const void *from, unsigned long n)
 {
 	unsigned long over;
 
@@ -343,10 +333,23 @@ copy_to_user(void __user *to, const void *from, unsigned long n)
 	return n;
 }
 
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
 #else /* __powerpc64__ */
 
-static inline unsigned long
-__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
+#define __copy_in_user(to, from, size) \
+	__copy_tofrom_user((to), (from), (size))
+
+extern unsigned long copy_from_user(void *to, const void __user *from,
+				    unsigned long n);
+extern unsigned long copy_to_user(void __user *to, const void *from,
+				  unsigned long n);
+extern unsigned long copy_in_user(void __user *to, const void __user *from,
+				  unsigned long n);
+
+static inline unsigned long __copy_from_user_inatomic(void *to,
+		const void __user *from, unsigned long n)
 {
 	if (__builtin_constant_p(n) && (n <= 8)) {
 		unsigned long ret;
@@ -370,8 +373,8 @@ __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
 	return __copy_tofrom_user((__force void __user *) to, from, n);
 }
 
-static inline unsigned long
-__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
+static inline unsigned long __copy_to_user_inatomic(void __user *to,
+		const void *from, unsigned long n)
 {
 	if (__builtin_constant_p(n) && (n <= 8)) {
 		unsigned long ret;
@@ -397,8 +400,8 @@ __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
 
 #endif /* __powerpc64__ */
 
-static inline unsigned long
-__copy_from_user(void *to, const void __user *from, unsigned long size)
+static inline unsigned long __copy_from_user(void *to,
+		const void __user *from, unsigned long size)
 {
 	might_sleep();
 #ifndef __powerpc64__
@@ -408,8 +411,8 @@ __copy_from_user(void *to, const void __user *from, unsigned long size)
 #endif /* __powerpc64__ */
 }
 
-static inline unsigned long
-__copy_to_user(void __user *to, const void *from, unsigned long size)
+static inline unsigned long __copy_to_user(void __user *to,
+		const void *from, unsigned long size)
 {
 	might_sleep();
 #ifndef __powerpc64__
@@ -419,21 +422,6 @@ __copy_to_user(void __user *to, const void *from, unsigned long size)
 #endif /* __powerpc64__ */
 }
 
-#ifndef __powerpc64__
-#define __copy_to_user_inatomic __copy_to_user
-#define __copy_from_user_inatomic __copy_from_user
-#else /* __powerpc64__ */
-#define __copy_in_user(to, from, size) \
-	__copy_tofrom_user((to), (from), (size))
-
-extern unsigned long copy_from_user(void *to, const void __user *from,
-				    unsigned long n);
-extern unsigned long copy_to_user(void __user *to, const void *from,
-				  unsigned long n);
-extern unsigned long copy_in_user(void __user *to, const void __user *from,
-				  unsigned long n);
-#endif /* __powerpc64__ */
-
 extern unsigned long __clear_user(void __user *addr, unsigned long size);
 
 static inline unsigned long clear_user(void __user *addr, unsigned long size)
@@ -466,11 +454,7 @@ static inline long strncpy_from_user(char *dst, const char __user *src,
  *
  * Return 0 for error
  */
-#ifndef __powerpc64__
 extern int __strnlen_user(const char __user *str, long len, unsigned long top);
-#else /* __powerpc64__ */
-extern int __strnlen_user(const char __user *str, long len);
-#endif /* __powerpc64__ */
 
 /*
  * Returns the length of the string at str (including the null byte),
@@ -482,18 +466,11 @@ extern int __strnlen_user(const char __user *str, long len);
  */
 static inline int strnlen_user(const char __user *str, long len)
 {
-#ifndef __powerpc64__
 	unsigned long top = current->thread.fs.seg;
 
 	if ((unsigned long)str > top)
 		return 0;
 	return __strnlen_user(str, len, top);
-#else /* __powerpc64__ */
-	might_sleep();
-	if (likely(access_ok(VERIFY_READ, str, 1)))
-		return __strnlen_user(str, len);
-	return 0;
-#endif /* __powerpc64__ */
 }
 
 #define strlen_user(str)	strnlen_user((str), 0x7ffffffe)