sh: use the new generic strnlen_user() function

This discards both the _32 and _64 versions in favour of the consolidated
generic one.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/Kconfig

@@ -33,6 +33,7 @@ config SUPERH
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_CMOS_UPDATE if SH_SH03 || SH_DREAMCAST
 	select GENERIC_STRNCPY_FROM_USER
+	select GENERIC_STRNLEN_USER
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
 	  and consumer electronics; it was also used in the Sega Dreamcast

arch/sh/include/asm/uaccess.h

@@ -104,6 +104,9 @@ struct __large_struct { unsigned long buf[100]; };
 
 extern long strncpy_from_user(char *dest, const char __user *src, long count);
 
+extern __must_check long strlen_user(const char __user *str);
+extern __must_check long strnlen_user(const char __user *str, long n);
+
 /* Generic arbitrary sized copy.  */
 /* Return the number of bytes NOT copied */
 __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
@@ -165,43 +168,6 @@ copy_to_user(void __user *to, const void *from, unsigned long n)
 	return __copy_size;
 }
 
-/**
- * strnlen_user: - Get the size of a string in user space.
- * @s: The string to measure.
- * @n: The maximum valid length
- *
- * Context: User context only.  This function may sleep.
- *
- * Get the size of a NUL-terminated string in user space.
- *
- * Returns the size of the string INCLUDING the terminating NUL.
- * On exception, returns 0.
- * If the string is too long, returns a value greater than @n.
- */
-static inline long strnlen_user(const char __user *s, long n)
-{
-	if (!__addr_ok(s))
-		return 0;
-	else
-		return __strnlen_user(s, n);
-}
-
-/**
- * strlen_user: - Get the size of a string in user space.
- * @str: The string to measure.
- *
- * Context: User context only.  This function may sleep.
- *
- * Get the size of a NUL-terminated string in user space.
- *
- * Returns the size of the string INCLUDING the terminating NUL.
- * On exception, returns 0.
- *
- * If there is a limit on the length of a valid string, you may wish to
- * consider using strnlen_user() instead.
- */
-#define strlen_user(str)	strnlen_user(str, ~0UL >> 1)
-
 /*
  * The exception table consists of pairs of addresses: the first is the
  * address of an instruction that is allowed to fault, and the second is

arch/sh/include/asm/uaccess_32.h

@@ -170,40 +170,4 @@ __asm__ __volatile__( \
 
 extern void __put_user_unknown(void);
 
-/*
- * Return the size of a string (including the ending 0 even when we have
- * exceeded the maximum string length).
- */
-static inline long __strnlen_user(const char __user *__s, long __n)
-{
-	unsigned long res;
-	unsigned long __dummy;
-
-	__asm__ __volatile__(
-		"1:\t"
-		"mov.b	@(%0,%3), %1\n\t"
-		"cmp/eq	%4, %0\n\t"
-		"bt/s	2f\n\t"
-		" add	#1, %0\n\t"
-		"tst	%1, %1\n\t"
-		"bf	1b\n\t"
-		"2:\n"
-		".section .fixup,\"ax\"\n"
-		"3:\n\t"
-		"mov.l	4f, %1\n\t"
-		"jmp	@%1\n\t"
-		" mov	#0, %0\n"
-		".balign 4\n"
-		"4:	.long 2b\n"
-		".previous\n"
-		".section __ex_table,\"a\"\n"
-		"	.balign 4\n"
-		"	.long 1b,3b\n"
-		".previous"
-		: "=z" (res), "=&r" (__dummy)
-		: "0" (0), "r" (__s), "r" (__n)
-		: "t");
-	return res;
-}
-
 #endif /* __ASM_SH_UACCESS_32_H */

arch/sh/include/asm/uaccess_64.h

@@ -84,6 +84,4 @@ extern long __put_user_asm_l(void *, long);
 extern long __put_user_asm_q(void *, long);
 extern void __put_user_unknown(void);
 
-extern long __strnlen_user(const char *__s, long __n);
-
 #endif /* __ASM_SH_UACCESS_64_H */

arch/sh/include/asm/word-at-a-time.h

@@ -0,0 +1,53 @@
+#ifndef __ASM_SH_WORD_AT_A_TIME_H
+#define __ASM_SH_WORD_AT_A_TIME_H
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+# include <asm-generic/word-at-a-time.h>
+#else
+/*
+ * Little-endian version cribbed from x86.
+ */
+struct word_at_a_time {
+	const unsigned long one_bits, high_bits;
+};
+
+#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
+
+/* Carl Chatfield / Jan Achrenius G+ version for 32-bit */
+static inline long count_masked_bytes(long mask)
+{
+	/* (000000 0000ff 00ffff ffffff) -> ( 1 1 2 3 ) */
+	long a = (0x0ff0001+mask) >> 23;
+	/* Fix the 1 for 00 case */
+	return a & mask;
+}
+
+/* Return nonzero if it has a zero */
+static inline unsigned long has_zero(unsigned long a, unsigned long *bits, const struct word_at_a_time *c)
+{
+	unsigned long mask = ((a - c->one_bits) & ~a) & c->high_bits;
+	*bits = mask;
+	return mask;
+}
+
+static inline unsigned long prep_zero_mask(unsigned long a, unsigned long bits, const struct word_at_a_time *c)
+{
+	return bits;
+}
+
+static inline unsigned long create_zero_mask(unsigned long bits)
+{
+	bits = (bits - 1) & ~bits;
+	return bits >> 7;
+}
+
+/* The mask we created is directly usable as a bytemask */
+#define zero_bytemask(mask) (mask)
+
+static inline unsigned long find_zero(unsigned long mask)
+{
+	return count_masked_bytes(mask);
+}
+#endif
+
+#endif

arch/sh/kernel/cpu/sh5/entry.S

@@ -1568,46 +1568,6 @@ ___clear_user_exit:
 
 #endif /* CONFIG_MMU */
 
-/*
- * extern long __strnlen_user(const char *__s, long __n)
- *
- * Inputs:
- * (r2)  source address
- * (r3)  source size in bytes
- *
- * Ouputs:
- * (r2)  -EFAULT (in case of faulting)
- *       string length (otherwise)
- */
-	.global	__strnlen_user
-__strnlen_user:
-	pta	___strnlen_user_set_reply, tr0
-	pta	___strnlen_user1, tr1
-	or	ZERO, ZERO, r5		/* r5 = counter */
-	movi	-(EFAULT), r6		/* r6 = reply, no real fixup */
-	or	ZERO, ZERO, r7		/* r7 = data, clear top byte of data */
-	beq	r3, ZERO, tr0
-
-___strnlen_user1:
-	ldx.b	r2, r5, r7		/* Fault address: only in reading */
-	addi	r3, -1, r3		/* No real fixup */
-	addi	r5, 1, r5
-	beq	r3, ZERO, tr0
-	bne	r7, ZERO, tr1
-! The line below used to be active.  This meant led to a junk byte lying between each pair
-! of entries in the argv & envp structures in memory.  Whilst the program saw the right data
-! via the argv and envp arguments to main, it meant the 'flat' representation visible through
-! /proc/$pid/cmdline was corrupt, causing trouble with ps, for example.
-!	addi	r5, 1, r5		/* Include '\0' */
-
-___strnlen_user_set_reply:
-	or	r5, ZERO, r6		/* If done, return counter */
-
-___strnlen_user_exit:
-	or	r6, ZERO, r2
-	ptabs	LINK, tr0
-	blink	tr0, ZERO
-
 /*
  * extern long __get_user_asm_?(void *val, long addr)
  *
@@ -1942,7 +1902,6 @@ asm_uaccess_start:
 	.long	___copy_user2, ___copy_user_exit
 	.long	___clear_user1, ___clear_user_exit
 #endif
-	.long	___strnlen_user1, ___strnlen_user_exit
 	.long	___get_user_asm_b1, ___get_user_asm_b_exit
 	.long	___get_user_asm_w1, ___get_user_asm_w_exit
 	.long	___get_user_asm_l1, ___get_user_asm_l_exit

arch/sh/kernel/sh_ksyms_64.c

@@ -32,7 +32,6 @@ EXPORT_SYMBOL(__get_user_asm_b);
 EXPORT_SYMBOL(__get_user_asm_w);
 EXPORT_SYMBOL(__get_user_asm_l);
 EXPORT_SYMBOL(__get_user_asm_q);
-EXPORT_SYMBOL(__strnlen_user);
 EXPORT_SYMBOL(__clear_user);
 EXPORT_SYMBOL(copy_page);
 EXPORT_SYMBOL(__copy_user);