alistair23-linux/arch/s390/lib/string.c
Paul Gortmaker d321796753 s390: Audit and remove any remaining unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each change instance
for the presence of either and replace as needed.  An instance
where module_param was used without moduleparam.h was also fixed,
as well as implicit use of ptrace.h and string.h headers.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-17 07:40:41 +01:00

344 lines
7.6 KiB
C

/*
* Optimized string functions
*
* S390 version
* Copyright IBM Corp. 2004
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#define IN_ARCH_STRING_C 1
#include <linux/types.h>
#include <linux/string.h>
#include <linux/export.h>
/*
* Helper functions to find the end of a string
*/
static inline char *__strend(const char *s)
{
register unsigned long r0 asm("0") = 0;
asm volatile ("0: srst %0,%1\n"
" jo 0b"
: "+d" (r0), "+a" (s) : : "cc", "memory");
return (char *) r0;
}
static inline char *__strnend(const char *s, size_t n)
{
register unsigned long r0 asm("0") = 0;
const char *p = s + n;
asm volatile ("0: srst %0,%1\n"
" jo 0b"
: "+d" (p), "+a" (s) : "d" (r0) : "cc", "memory");
return (char *) p;
}
/**
* strlen - Find the length of a string
* @s: The string to be sized
*
* returns the length of @s
*/
size_t strlen(const char *s)
{
return __strend(s) - s;
}
EXPORT_SYMBOL(strlen);
/**
* strnlen - Find the length of a length-limited string
* @s: The string to be sized
* @n: The maximum number of bytes to search
*
* returns the minimum of the length of @s and @n
*/
size_t strnlen(const char * s, size_t n)
{
return __strnend(s, n) - s;
}
EXPORT_SYMBOL(strnlen);
/**
* strcpy - Copy a %NUL terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
*
* returns a pointer to @dest
*/
char *strcpy(char *dest, const char *src)
{
register int r0 asm("0") = 0;
char *ret = dest;
asm volatile ("0: mvst %0,%1\n"
" jo 0b"
: "+&a" (dest), "+&a" (src) : "d" (r0)
: "cc", "memory" );
return ret;
}
EXPORT_SYMBOL(strcpy);
/**
* strlcpy - Copy a %NUL terminated string into a sized buffer
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @size: size of destination buffer
*
* Compatible with *BSD: the result is always a valid
* NUL-terminated string that fits in the buffer (unless,
* of course, the buffer size is zero). It does not pad
* out the result like strncpy() does.
*/
size_t strlcpy(char *dest, const char *src, size_t size)
{
size_t ret = __strend(src) - src;
if (size) {
size_t len = (ret >= size) ? size-1 : ret;
dest[len] = '\0';
memcpy(dest, src, len);
}
return ret;
}
EXPORT_SYMBOL(strlcpy);
/**
* strncpy - Copy a length-limited, %NUL-terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @n: The maximum number of bytes to copy
*
* The result is not %NUL-terminated if the source exceeds
* @n bytes.
*/
char *strncpy(char *dest, const char *src, size_t n)
{
size_t len = __strnend(src, n) - src;
memset(dest + len, 0, n - len);
memcpy(dest, src, len);
return dest;
}
EXPORT_SYMBOL(strncpy);
/**
* strcat - Append one %NUL-terminated string to another
* @dest: The string to be appended to
* @src: The string to append to it
*
* returns a pointer to @dest
*/
char *strcat(char *dest, const char *src)
{
register int r0 asm("0") = 0;
unsigned long dummy;
char *ret = dest;
asm volatile ("0: srst %0,%1\n"
" jo 0b\n"
"1: mvst %0,%2\n"
" jo 1b"
: "=&a" (dummy), "+a" (dest), "+a" (src)
: "d" (r0), "0" (0UL) : "cc", "memory" );
return ret;
}
EXPORT_SYMBOL(strcat);
/**
* strlcat - Append a length-limited, %NUL-terminated string to another
* @dest: The string to be appended to
* @src: The string to append to it
* @n: The size of the destination buffer.
*/
size_t strlcat(char *dest, const char *src, size_t n)
{
size_t dsize = __strend(dest) - dest;
size_t len = __strend(src) - src;
size_t res = dsize + len;
if (dsize < n) {
dest += dsize;
n -= dsize;
if (len >= n)
len = n - 1;
dest[len] = '\0';
memcpy(dest, src, len);
}
return res;
}
EXPORT_SYMBOL(strlcat);
/**
* strncat - Append a length-limited, %NUL-terminated string to another
* @dest: The string to be appended to
* @src: The string to append to it
* @n: The maximum numbers of bytes to copy
*
* returns a pointer to @dest
*
* Note that in contrast to strncpy, strncat ensures the result is
* terminated.
*/
char *strncat(char *dest, const char *src, size_t n)
{
size_t len = __strnend(src, n) - src;
char *p = __strend(dest);
p[len] = '\0';
memcpy(p, src, len);
return dest;
}
EXPORT_SYMBOL(strncat);
/**
* strcmp - Compare two strings
* @cs: One string
* @ct: Another string
*
* returns 0 if @cs and @ct are equal,
* < 0 if @cs is less than @ct
* > 0 if @cs is greater than @ct
*/
int strcmp(const char *cs, const char *ct)
{
register int r0 asm("0") = 0;
int ret = 0;
asm volatile ("0: clst %2,%3\n"
" jo 0b\n"
" je 1f\n"
" ic %0,0(%2)\n"
" ic %1,0(%3)\n"
" sr %0,%1\n"
"1:"
: "+d" (ret), "+d" (r0), "+a" (cs), "+a" (ct)
: : "cc", "memory");
return ret;
}
EXPORT_SYMBOL(strcmp);
/**
* strrchr - Find the last occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char * strrchr(const char * s, int c)
{
size_t len = __strend(s) - s;
if (len)
do {
if (s[len] == (char) c)
return (char *) s + len;
} while (--len > 0);
return NULL;
}
EXPORT_SYMBOL(strrchr);
static inline int clcle(const char *s1, unsigned long l1,
const char *s2, unsigned long l2)
{
register unsigned long r2 asm("2") = (unsigned long) s1;
register unsigned long r3 asm("3") = (unsigned long) l1;
register unsigned long r4 asm("4") = (unsigned long) s2;
register unsigned long r5 asm("5") = (unsigned long) l2;
int cc;
asm volatile ("0: clcle %1,%3,0\n"
" jo 0b\n"
" ipm %0\n"
" srl %0,28"
: "=&d" (cc), "+a" (r2), "+a" (r3),
"+a" (r4), "+a" (r5) : : "cc", "memory");
return cc;
}
/**
* strstr - Find the first substring in a %NUL terminated string
* @s1: The string to be searched
* @s2: The string to search for
*/
char * strstr(const char * s1,const char * s2)
{
int l1, l2;
l2 = __strend(s2) - s2;
if (!l2)
return (char *) s1;
l1 = __strend(s1) - s1;
while (l1-- >= l2) {
int cc;
cc = clcle(s1, l2, s2, l2);
if (!cc)
return (char *) s1;
s1++;
}
return NULL;
}
EXPORT_SYMBOL(strstr);
/**
* memchr - Find a character in an area of memory.
* @s: The memory area
* @c: The byte to search for
* @n: The size of the area.
*
* returns the address of the first occurrence of @c, or %NULL
* if @c is not found
*/
void *memchr(const void *s, int c, size_t n)
{
register int r0 asm("0") = (char) c;
const void *ret = s + n;
asm volatile ("0: srst %0,%1\n"
" jo 0b\n"
" jl 1f\n"
" la %0,0\n"
"1:"
: "+a" (ret), "+&a" (s) : "d" (r0) : "cc", "memory");
return (void *) ret;
}
EXPORT_SYMBOL(memchr);
/**
* memcmp - Compare two areas of memory
* @cs: One area of memory
* @ct: Another area of memory
* @count: The size of the area.
*/
int memcmp(const void *cs, const void *ct, size_t n)
{
int ret;
ret = clcle(cs, n, ct, n);
if (ret)
ret = ret == 1 ? -1 : 1;
return ret;
}
EXPORT_SYMBOL(memcmp);
/**
* memscan - Find a character in an area of memory.
* @s: The memory area
* @c: The byte to search for
* @n: The size of the area.
*
* returns the address of the first occurrence of @c, or 1 byte past
* the area if @c is not found
*/
void *memscan(void *s, int c, size_t n)
{
register int r0 asm("0") = (char) c;
const void *ret = s + n;
asm volatile ("0: srst %0,%1\n"
" jo 0b\n"
: "+a" (ret), "+&a" (s) : "d" (r0) : "cc", "memory");
return (void *) ret;
}
EXPORT_SYMBOL(memscan);