From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- arch/s390/lib/string.c | 348 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 348 insertions(+) create mode 100644 arch/s390/lib/string.c (limited to 'arch/s390/lib/string.c') diff --git a/arch/s390/lib/string.c b/arch/s390/lib/string.c new file mode 100644 index 0000000000..7d87418182 --- /dev/null +++ b/arch/s390/lib/string.c @@ -0,0 +1,348 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Optimized string functions + * + * S390 version + * Copyright IBM Corp. 2004 + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) + */ + +#define IN_ARCH_STRING_C 1 +#ifndef __NO_FORTIFY +# define __NO_FORTIFY +#endif + +#include +#include +#include + +/* + * Helper functions to find the end of a string + */ +static inline char *__strend(const char *s) +{ + unsigned long e = 0; + + asm volatile( + " lghi 0,0\n" + "0: srst %[e],%[s]\n" + " jo 0b\n" + : [e] "+&a" (e), [s] "+&a" (s) + : + : "cc", "memory", "0"); + return (char *)e; +} + +static inline char *__strnend(const char *s, size_t n) +{ + const char *p = s + n; + + asm volatile( + " lghi 0,0\n" + "0: srst %[p],%[s]\n" + " jo 0b\n" + : [p] "+&d" (p), [s] "+&a" (s) + : + : "cc", "memory", "0"); + return (char *)p; +} + +/** + * strlen - Find the length of a string + * @s: The string to be sized + * + * returns the length of @s + */ +#ifdef __HAVE_ARCH_STRLEN +size_t strlen(const char *s) +{ + return __strend(s) - s; +} +EXPORT_SYMBOL(strlen); +#endif + +/** + * 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 + */ +#ifdef __HAVE_ARCH_STRNLEN +size_t strnlen(const char *s, size_t n) +{ + return __strnend(s, n) - s; +} +EXPORT_SYMBOL(strnlen); +#endif + +/** + * 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 + */ +#ifdef __HAVE_ARCH_STRCPY +char *strcpy(char *dest, const char *src) +{ + char *ret = dest; + + asm volatile( + " lghi 0,0\n" + "0: mvst %[dest],%[src]\n" + " jo 0b\n" + : [dest] "+&a" (dest), [src] "+&a" (src) + : + : "cc", "memory", "0"); + return ret; +} +EXPORT_SYMBOL(strcpy); +#endif + +/** + * 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. + */ +#ifdef __HAVE_ARCH_STRNCPY +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); +#endif + +/** + * 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 + */ +#ifdef __HAVE_ARCH_STRCAT +char *strcat(char *dest, const char *src) +{ + unsigned long dummy = 0; + char *ret = dest; + + asm volatile( + " lghi 0,0\n" + "0: srst %[dummy],%[dest]\n" + " jo 0b\n" + "1: mvst %[dummy],%[src]\n" + " jo 1b\n" + : [dummy] "+&a" (dummy), [dest] "+&a" (dest), [src] "+&a" (src) + : + : "cc", "memory", "0"); + return ret; +} +EXPORT_SYMBOL(strcat); +#endif + +/** + * 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. + */ +#ifdef __HAVE_ARCH_STRLCAT +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); +#endif + +/** + * 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. + */ +#ifdef __HAVE_ARCH_STRNCAT +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); +#endif + +/** + * strcmp - Compare two strings + * @s1: One string + * @s2: Another string + * + * returns 0 if @s1 and @s2 are equal, + * < 0 if @s1 is less than @s2 + * > 0 if @s1 is greater than @s2 + */ +#ifdef __HAVE_ARCH_STRCMP +int strcmp(const char *s1, const char *s2) +{ + int ret = 0; + + asm volatile( + " lghi 0,0\n" + "0: clst %[s1],%[s2]\n" + " jo 0b\n" + " je 1f\n" + " ic %[ret],0(%[s1])\n" + " ic 0,0(%[s2])\n" + " sr %[ret],0\n" + "1:" + : [ret] "+&d" (ret), [s1] "+&a" (s1), [s2] "+&a" (s2) + : + : "cc", "memory", "0"); + return ret; +} +EXPORT_SYMBOL(strcmp); +#endif + +static inline int clcle(const char *s1, unsigned long l1, + const char *s2, unsigned long l2) +{ + union register_pair r1 = { .even = (unsigned long)s1, .odd = l1, }; + union register_pair r3 = { .even = (unsigned long)s2, .odd = l2, }; + int cc; + + asm volatile( + "0: clcle %[r1],%[r3],0\n" + " jo 0b\n" + " ipm %[cc]\n" + " srl %[cc],28\n" + : [cc] "=&d" (cc), [r1] "+&d" (r1.pair), [r3] "+&d" (r3.pair) + : + : "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 + */ +#ifdef __HAVE_ARCH_STRSTR +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); +#endif + +/** + * 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 + */ +#ifdef __HAVE_ARCH_MEMCHR +void *memchr(const void *s, int c, size_t n) +{ + const void *ret = s + n; + + asm volatile( + " lgr 0,%[c]\n" + "0: srst %[ret],%[s]\n" + " jo 0b\n" + " jl 1f\n" + " la %[ret],0\n" + "1:" + : [ret] "+&a" (ret), [s] "+&a" (s) + : [c] "d" (c) + : "cc", "memory", "0"); + return (void *) ret; +} +EXPORT_SYMBOL(memchr); +#endif + +/** + * memcmp - Compare two areas of memory + * @s1: One area of memory + * @s2: Another area of memory + * @n: The size of the area. + */ +#ifdef __HAVE_ARCH_MEMCMP +int memcmp(const void *s1, const void *s2, size_t n) +{ + int ret; + + ret = clcle(s1, n, s2, n); + if (ret) + ret = ret == 1 ? -1 : 1; + return ret; +} +EXPORT_SYMBOL(memcmp); +#endif + +/** + * 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 + */ +#ifdef __HAVE_ARCH_MEMSCAN +void *memscan(void *s, int c, size_t n) +{ + const void *ret = s + n; + + asm volatile( + " lgr 0,%[c]\n" + "0: srst %[ret],%[s]\n" + " jo 0b\n" + : [ret] "+&a" (ret), [s] "+&a" (s) + : [c] "d" (c) + : "cc", "memory", "0"); + return (void *)ret; +} +EXPORT_SYMBOL(memscan); +#endif -- cgit v1.2.3