x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 326 insertions, 0 deletions

diff --git a/arch/x86/include/asm/string_32.h b/arch/x86/include/asm/string_32.h
new file mode 100644
index 000000000000..487843ed245a
--- /dev/null
+++ b/arch/x86/include/asm/string_32.h
@@ -0,0 +1,326 @@
+#ifndef ASM_X86__STRING_32_H
+#define ASM_X86__STRING_32_H
+
+#ifdef __KERNEL__
+
+/* Let gcc decide whether to inline or use the out of line functions */
+
+#define __HAVE_ARCH_STRCPY
+extern char *strcpy(char *dest, const char *src);
+
+#define __HAVE_ARCH_STRNCPY
+extern char *strncpy(char *dest, const char *src, size_t count);
+
+#define __HAVE_ARCH_STRCAT
+extern char *strcat(char *dest, const char *src);
+
+#define __HAVE_ARCH_STRNCAT
+extern char *strncat(char *dest, const char *src, size_t count);
+
+#define __HAVE_ARCH_STRCMP
+extern int strcmp(const char *cs, const char *ct);
+
+#define __HAVE_ARCH_STRNCMP
+extern int strncmp(const char *cs, const char *ct, size_t count);
+
+#define __HAVE_ARCH_STRCHR
+extern char *strchr(const char *s, int c);
+
+#define __HAVE_ARCH_STRLEN
+extern size_t strlen(const char *s);
+
+static __always_inline void *__memcpy(void *to, const void *from, size_t n)
+{
+        int d0, d1, d2;
+        asm volatile("rep ; movsl\n\t"
+                     "movl %4,%%ecx\n\t"
+                     "andl $3,%%ecx\n\t"
+                     "jz 1f\n\t"
+                     "rep ; movsb\n\t"
+                     "1:"
+                     : "=&c" (d0), "=&D" (d1), "=&S" (d2)
+                     : "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from)
+                     : "memory");
+        return to;
+}
+
+/*
+ * This looks ugly, but the compiler can optimize it totally,
+ * as the count is constant.
+ */
+static __always_inline void *__constant_memcpy(void *to, const void *from,
+                                               size_t n)
+{
+        long esi, edi;
+        if (!n)
+                return to;
+
+        switch (n) {
+        case 1:
+                *(char *)to = *(char *)from;
+                return to;
+        case 2:
+                *(short *)to = *(short *)from;
+                return to;
+        case 4:
+                *(int *)to = *(int *)from;
+                return to;
+
+        case 3:
+                *(short *)to = *(short *)from;
+                *((char *)to + 2) = *((char *)from + 2);
+                return to;
+        case 5:
+                *(int *)to = *(int *)from;
+                *((char *)to + 4) = *((char *)from + 4);
+                return to;
+        case 6:
+                *(int *)to = *(int *)from;
+                *((short *)to + 2) = *((short *)from + 2);
+                return to;
+        case 8:
+                *(int *)to = *(int *)from;
+                *((int *)to + 1) = *((int *)from + 1);
+                return to;
+        }
+
+        esi = (long)from;
+        edi = (long)to;
+        if (n >= 5 * 4) {
+                /* large block: use rep prefix */
+                int ecx;
+                asm volatile("rep ; movsl"
+                             : "=&c" (ecx), "=&D" (edi), "=&S" (esi)
+                             : "0" (n / 4), "1" (edi), "2" (esi)
+                             : "memory"
+                );
+        } else {
+                /* small block: don't clobber ecx + smaller code */
+                if (n >= 4 * 4)
+                        asm volatile("movsl"
+                                     : "=&D"(edi), "=&S"(esi)
+                                     : "0"(edi), "1"(esi)
+                                     : "memory");
+                if (n >= 3 * 4)
+                        asm volatile("movsl"
+                                     : "=&D"(edi), "=&S"(esi)
+                                     : "0"(edi), "1"(esi)
+                                     : "memory");
+                if (n >= 2 * 4)
+                        asm volatile("movsl"
+                                     : "=&D"(edi), "=&S"(esi)
+                                     : "0"(edi), "1"(esi)
+                                     : "memory");
+                if (n >= 1 * 4)
+                        asm volatile("movsl"
+                                     : "=&D"(edi), "=&S"(esi)
+                                     : "0"(edi), "1"(esi)
+                                     : "memory");
+        }
+        switch (n % 4) {
+                /* tail */
+        case 0:
+                return to;
+        case 1:
+                asm volatile("movsb"
+                             : "=&D"(edi), "=&S"(esi)
+                             : "0"(edi), "1"(esi)
+                             : "memory");
+                return to;
+        case 2:
+                asm volatile("movsw"
+                             : "=&D"(edi), "=&S"(esi)
+                             : "0"(edi), "1"(esi)
+                             : "memory");
+                return to;
+        default:
+                asm volatile("movsw\n\tmovsb"
+                             : "=&D"(edi), "=&S"(esi)
+                             : "0"(edi), "1"(esi)
+                             : "memory");
+                return to;
+        }
+}
+
+#define __HAVE_ARCH_MEMCPY
+
+#ifdef CONFIG_X86_USE_3DNOW
+
+#include <asm/mmx.h>
+
+/*
+ *      This CPU favours 3DNow strongly (eg AMD Athlon)
+ */
+
+static inline void *__constant_memcpy3d(void *to, const void *from, size_t len)
+{
+        if (len < 512)
+                return __constant_memcpy(to, from, len);
+        return _mmx_memcpy(to, from, len);
+}
+
+static inline void *__memcpy3d(void *to, const void *from, size_t len)
+{
+        if (len < 512)
+                return __memcpy(to, from, len);
+        return _mmx_memcpy(to, from, len);
+}
+
+#define memcpy(t, f, n)                         \
+        (__builtin_constant_p((n))              \
+         ? __constant_memcpy3d((t), (f), (n))   \
+         : __memcpy3d((t), (f), (n)))
+
+#else
+
+/*
+ *      No 3D Now!
+ */
+
+#define memcpy(t, f, n)                         \
+        (__builtin_constant_p((n))              \
+         ? __constant_memcpy((t), (f), (n))     \
+         : __memcpy((t), (f), (n)))
+
+#endif
+
+#define __HAVE_ARCH_MEMMOVE
+void *memmove(void *dest, const void *src, size_t n);
+
+#define memcmp __builtin_memcmp
+
+#define __HAVE_ARCH_MEMCHR
+extern void *memchr(const void *cs, int c, size_t count);
+
+static inline void *__memset_generic(void *s, char c, size_t count)
+{
+        int d0, d1;
+        asm volatile("rep\n\t"
+                     "stosb"
+                     : "=&c" (d0), "=&D" (d1)
+                     : "a" (c), "1" (s), "0" (count)
+                     : "memory");
+        return s;
+}
+
+/* we might want to write optimized versions of these later */
+#define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count))
+
+/*
+ * memset(x, 0, y) is a reasonably common thing to do, so we want to fill
+ * things 32 bits at a time even when we don't know the size of the
+ * area at compile-time..
+ */
+static __always_inline
+void *__constant_c_memset(void *s, unsigned long c, size_t count)
+{
+        int d0, d1;
+        asm volatile("rep ; stosl\n\t"
+                     "testb $2,%b3\n\t"
+                     "je 1f\n\t"
+                     "stosw\n"
+                     "1:\ttestb $1,%b3\n\t"
+                     "je 2f\n\t"
+                     "stosb\n"
+                     "2:"
+                     : "=&c" (d0), "=&D" (d1)
+                     : "a" (c), "q" (count), "0" (count/4), "1" ((long)s)
+                     : "memory");
+        return s;
+}
+
+/* Added by Gertjan van Wingerde to make minix and sysv module work */
+#define __HAVE_ARCH_STRNLEN
+extern size_t strnlen(const char *s, size_t count);
+/* end of additional stuff */
+
+#define __HAVE_ARCH_STRSTR
+extern char *strstr(const char *cs, const char *ct);
+
+/*
+ * This looks horribly ugly, but the compiler can optimize it totally,
+ * as we by now know that both pattern and count is constant..
+ */
+static __always_inline
+void *__constant_c_and_count_memset(void *s, unsigned long pattern,
+                                    size_t count)
+{
+        switch (count) {
+        case 0:
+                return s;
+        case 1:
+                *(unsigned char *)s = pattern & 0xff;
+                return s;
+        case 2:
+                *(unsigned short *)s = pattern & 0xffff;
+                return s;
+        case 3:
+                *(unsigned short *)s = pattern & 0xffff;
+                *((unsigned char *)s + 2) = pattern & 0xff;
+                return s;
+        case 4:
+                *(unsigned long *)s = pattern;
+                return s;
+        }
+
+#define COMMON(x)                                                       \
+        asm volatile("rep ; stosl"                                      \
+                     x                                                  \
+                     : "=&c" (d0), "=&D" (d1)                           \
+                     : "a" (eax), "0" (count/4), "1" ((long)s)  \
+                     : "memory")
+
+        {
+                int d0, d1;
+#if __GNUC__ == 4 && __GNUC_MINOR__ == 0
+                /* Workaround for broken gcc 4.0 */
+                register unsigned long eax asm("%eax") = pattern;
+#else
+                unsigned long eax = pattern;
+#endif
+
+                switch (count % 4) {
+                case 0:
+                        COMMON("");
+                        return s;
+                case 1:
+                        COMMON("\n\tstosb");
+                        return s;
+                case 2:
+                        COMMON("\n\tstosw");
+                        return s;
+                default:
+                        COMMON("\n\tstosw\n\tstosb");
+                        return s;
+                }
+        }
+
+#undef COMMON
+}
+
+#define __constant_c_x_memset(s, c, count)                      \
+        (__builtin_constant_p(count)                            \
+         ? __constant_c_and_count_memset((s), (c), (count))     \
+         : __constant_c_memset((s), (c), (count)))
+
+#define __memset(s, c, count)                           \
+        (__builtin_constant_p(count)                    \
+         ? __constant_count_memset((s), (c), (count))   \
+         : __memset_generic((s), (c), (count)))
+
+#define __HAVE_ARCH_MEMSET
+#define memset(s, c, count)                                             \
+        (__builtin_constant_p(c)                                        \
+         ? __constant_c_x_memset((s), (0x01010101UL * (unsigned char)(c)), \
+                                 (count))                               \
+         : __memset((s), (c), (count)))
+
+/*
+ * find the first occurrence of byte 'c', or 1 past the area if none
+ */
+#define __HAVE_ARCH_MEMSCAN
+extern void *memscan(void *addr, int c, size_t size);
+
+#endif /* __KERNEL__ */
+
+#endif /* ASM_X86__STRING_32_H */