diff options
Diffstat (limited to 'arch/s390/lib/string.c')
| -rw-r--r-- | arch/s390/lib/string.c | 236 |
1 files changed, 210 insertions, 26 deletions
diff --git a/arch/s390/lib/string.c b/arch/s390/lib/string.c index 757f58960198..32e0e6b1e623 100644 --- a/arch/s390/lib/string.c +++ b/arch/s390/lib/string.c @@ -15,8 +15,218 @@ #include <linux/types.h> #include <linux/string.h> #include <linux/export.h> +#include <asm/facility.h> #include <asm/asm.h> +#define SYMBOL_FUNCTION_ALIAS(alias, name) \ +asm(".globl " __stringify(alias) "\n\t" \ + ".set " __stringify(alias) "," __stringify(name)) + +#ifdef __HAVE_ARCH_MEMMOVE +noinstr void *__memmove(void *dest, const void *src, size_t n) +{ + const char *s = src; + char *d = dest; + + if (!n) + return dest; + if ((d <= s || d >= s + n)) { + /* Forward copy */ + while (n >= 256) { + asm volatile( + " mvc 0(256,%[d]),0(%[s])\n" + : + : [d] "a" (d), [s] "a" (s) + : "memory"); + d += 256; + s += 256; + n -= 256; + } + if (n) { + asm volatile( + " exrl %[n],0f\n" + " j 1f\n" + "0: mvc 0(1,%[d]),0(%[s])\n" + "1:" + : + : [d] "a" (d), [s] "a" (s), [n] "a" (n - 1) + : "memory"); + } + return dest; + } + /* Backward copy */ + if (test_facility(61)) { + /* Use mvcrl instruction if available */ + while (n >= 256) { + asm volatile( + " lghi %%r0,255\n" + " .insn sse,0xe50a00000000,%[d],%[s]\n" + : [d] "=Q" (*(d + n - 256)) + : [s] "Q" (*(s + n - 256)) + : "0", "memory"); + n -= 256; + } + if (n) { + asm volatile( + " lgr %%r0,%[n]\n" + " .insn sse,0xe50a00000000,%[d],%[s]\n" + : [d] "=Q" (*d) + : [s] "Q" (*s), [n] "d" (n - 1) + : "0", "memory"); + } + } else { + while (n--) + d[n] = s[n]; + } + return dest; +} +SYMBOL_FUNCTION_ALIAS(memmove, __memmove); +EXPORT_SYMBOL(__memmove); +EXPORT_SYMBOL(memmove); +#endif + +#ifdef __HAVE_ARCH_MEMSET +noinstr void *__memset(void *s, int c, size_t n) +{ + char *xs = s; + + if (!n) + return s; + if (!c) { + /* Clear memory */ + while (n >= 256) { + asm volatile( + " xc 0(256,%[xs]),0(%[xs])" + : + : [xs] "a" (xs) + : "cc", "memory"); + xs += 256; + n -= 256; + } + if (!n) + return s; + asm volatile( + " exrl %[n],0f\n" + " j 1f\n" + "0: xc 0(1,%[xs]),0(%[xs])\n" + "1:" + : + : [xs] "a" (xs), [n] "a" (n - 1) + : "cc", "memory"); + } else { + /* Fill memory */ + while (n >= 256) { + *xs = c; + asm volatile( + " mvc 1(255,%[xs]),0(%[xs])" + : + : [xs] "a" (xs) + : "memory"); + xs += 256; + n -= 256; + } + if (!n) + return s; + *xs = c; + if (n == 1) + return s; + asm volatile( + " exrl %[n],0f\n" + " j 1f\n" + "0: mvc 1(1,%[xs]),0(%[xs])\n" + "1:" + : + : [xs] "a" (xs), [n] "a" (n - 2) + : "memory"); + } + return s; +} +SYMBOL_FUNCTION_ALIAS(memset, __memset); +EXPORT_SYMBOL(__memset); +EXPORT_SYMBOL(memset); +#endif + +#ifdef __HAVE_ARCH_MEMCPY +noinstr void *__memcpy(void *dest, const void *src, size_t n) +{ + void *d = dest; + + if (!n) + return d; + while (n >= 256) { + asm volatile( + " mvc 0(256,%[dest]),0(%[src])" + : + : [dest] "a" (dest), [src] "a" (src) + : "memory"); + dest += 256; + src += 256; + n -= 256; + } + if (!n) + return d; + asm volatile( + " exrl %[n],1f\n" + " j 2f\n" + "1: mvc 0(1,%[dest]),0(%[src])\n" + "2:" + : + : [dest] "a" (dest), [src] "a" (src), [n] "a" (n - 1) + : "memory"); + return d; +} +SYMBOL_FUNCTION_ALIAS(memcpy, __memcpy); +EXPORT_SYMBOL(__memcpy); +EXPORT_SYMBOL(memcpy); +#endif + +#define DEFINE_MEMSET(_bits, _bytes, _type) \ +void *__memset##_bits(_type *s, _type v, size_t n) \ +{ \ + _type *xs = s; \ + \ + if (!n) \ + return s; \ + while (n >= 256) { \ + *xs = v; \ + asm volatile( \ + " mvc %[_b](256-%[_b],%[xs]),0(%[xs])\n" \ + : \ + : [xs] "a" (xs), [_b] "i" (_bytes) \ + : "memory"); \ + xs = (_type *)((char *)xs + 256); \ + n -= 256; \ + } \ + if (!n) \ + return s; \ + *xs = v; \ + if (n == _bytes) \ + return s; \ + n -= _bytes + 1; \ + asm volatile( \ + " exrl %[n],1f\n" \ + " j 2f\n" \ + "1: mvc %[_b](1,%[xs]),0(%[xs])\n" \ + "2:" \ + : \ + : [n] "a" (n), [xs] "a" (xs), [_b] "i" (_bytes) \ + : "memory"); \ + return s; \ +} \ +EXPORT_SYMBOL(__memset##_bits) + +#ifdef __HAVE_ARCH_MEMSET16 +DEFINE_MEMSET(16, 2, uint16_t); +#endif + +#ifdef __HAVE_ARCH_MEMSET32 +DEFINE_MEMSET(32, 4, uint32_t); +#endif + +#ifdef __HAVE_ARCH_MEMSET64 +DEFINE_MEMSET(64, 8, uint64_t); +#endif + /* * Helper functions to find the end of a string */ @@ -105,32 +315,6 @@ 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 |