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-rw-r--r--arch/x86/include/asm/string_32.h230
1 files changed, 230 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 000000000..32c0d981a
--- /dev/null
+++ b/arch/x86/include/asm/string_32.h
@@ -0,0 +1,230 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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
+extern void *memcpy(void *, const void *, size_t);
+
+#ifndef CONFIG_FORTIFY_SOURCE
+
+#define memcpy(t, f, n) __builtin_memcpy(t, f, n)
+
+#endif /* !CONFIG_FORTIFY_SOURCE */
+
+#define __HAVE_ARCH_MEMMOVE
+void *memmove(void *dest, const void *src, size_t n);
+
+extern int memcmp(const void *, const void *, size_t);
+#ifndef CONFIG_FORTIFY_SOURCE
+#define memcmp __builtin_memcmp
+#endif
+
+#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))
+
+/* 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);
+
+#define __memset(s, c, count) \
+ (__builtin_constant_p(count) \
+ ? __constant_count_memset((s), (c), (count)) \
+ : __memset_generic((s), (c), (count)))
+
+#define __HAVE_ARCH_MEMSET
+extern void *memset(void *, int, size_t);
+#ifndef CONFIG_FORTIFY_SOURCE
+#define memset(s, c, count) __builtin_memset(s, c, count)
+#endif /* !CONFIG_FORTIFY_SOURCE */
+
+#define __HAVE_ARCH_MEMSET16
+static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
+{
+ int d0, d1;
+ asm volatile("rep\n\t"
+ "stosw"
+ : "=&c" (d0), "=&D" (d1)
+ : "a" (v), "1" (s), "0" (n)
+ : "memory");
+ return s;
+}
+
+#define __HAVE_ARCH_MEMSET32
+static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
+{
+ int d0, d1;
+ asm volatile("rep\n\t"
+ "stosl"
+ : "=&c" (d0), "=&D" (d1)
+ : "a" (v), "1" (s), "0" (n)
+ : "memory");
+ return s;
+}
+
+/*
+ * 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 */