Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * This provides an optimized implementation of memcpy, and a simplified
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  * implementation of memset and memmove. These are used here because the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * standard kernel runtime versions are not yet available and we don't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * trust the gcc built-in implementations as they may do unexpected things
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  * (e.g. FPU ops) in the minimal decompression stub execution environment.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include "error.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include "../string.c"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #ifdef CONFIG_X86_32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) static void *____memcpy(void *dest, const void *src, size_t n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	int d0, d1, d2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	asm volatile(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 		"rep ; movsl\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 		"movl %4,%%ecx\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 		"rep ; movsb\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 		: "memory");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	return dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static void *____memcpy(void *dest, const void *src, size_t n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	long d0, d1, d2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	asm volatile(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 		"rep ; movsq\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		"movq %4,%%rcx\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		"rep ; movsb\n\t"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		: "memory");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	return dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) void *memset(void *s, int c, size_t n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	char *ss = s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	for (i = 0; i < n; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		ss[i] = c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	return s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) void *memmove(void *dest, const void *src, size_t n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	unsigned char *d = dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	const unsigned char *s = src;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	if (d <= s || d - s >= n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		return ____memcpy(dest, src, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	while (n-- > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		d[n] = s[n];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	return dest;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) /* Detect and warn about potential overlaps, but handle them with memmove. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) void *memcpy(void *dest, const void *src, size_t n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	if (dest > src && dest - src < n) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 		warn("Avoiding potentially unsafe overlapping memcpy()!");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		return memmove(dest, src, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	return ____memcpy(dest, src, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) #ifdef CONFIG_KASAN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) extern void *__memset(void *s, int c, size_t n) __alias(memset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) extern void *__memmove(void *dest, const void *src, size_t n) __alias(memmove);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) extern void *__memcpy(void *dest, const void *src, size_t n) __alias(memcpy);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) #endif