[PATCH v2] lib/decompress_unxz.c: removing all memory helper functions

@@ -9,6 +9,7 @@
 extern unsigned long free_mem_ptr;
 extern unsigned long free_mem_end_ptr;
 extern void error(char *);
+extern int memcmp(const void *, const void *, size_t);
 
 #define STATIC static
 #define STATIC_RW_DATA	/* non-static please */

@@ -45,8 +46,6 @@ extern void error(char *);
 #endif
 
 #ifdef CONFIG_KERNEL_XZ
-#define memmove memmove
-#define memcpy memcpy
 #include "../../../../lib/decompress_unxz.c"
 #endif
 

@@ -6,6 +6,7 @@
 
 #include <linux/string.h>
 
+#define	__HAVE_PREBOOT_ARCH_MEMCPY
 void *memcpy(void *__dest, __const void *__src, size_t __n)
 {
 	int i = 0;

@@ -40,22 +41,6 @@ void *memcpy(void *__dest, __const void *__src, size_t __n)
 	return __dest;
 }
 
-void *memmove(void *__dest, __const void *__src, size_t count)
-{
-	unsigned char *d = __dest;
-	const unsigned char *s = __src;
-
-	if (__dest = __src)
-		return __dest;
-
-	if (__dest < __src)
-		return memcpy(__dest, __src, count);
-
-	while (count--)
-		d[count] = s[count];
-	return __dest;
-}
-
 size_t strlen(const char *s)
 {
 	const char *sc = s;

@@ -65,19 +50,6 @@ size_t strlen(const char *s)
 	return sc - s;
 }
 
-int memcmp(const void *cs, const void *ct, size_t count)
-{
-	const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
-	int res = 0;
-
-	while (su1 < end) {
-		res = *su1++ - *su2++;
-		if (res)
-			break;
-	}
-	return res;
-}
-
 int strcmp(const char *cs, const char *ct)
 {
 	unsigned char c1, c2;

@@ -113,15 +85,10 @@ char *strchr(const char *s, int c)
 
 #undef memset
 
-void *memset(void *s, int c, size_t count)
-{
-	char *xs = s;
-	while (count--)
-		*xs++ = c;
-	return s;
-}
-
 void __memzero(void *s, size_t count)
 {
 	memset(s, 0, count);
 }
+
+#include "../../../../lib/boot/mem.c"
+

@@ -67,6 +67,8 @@ static int puts(const char *s)
 	return 0;
 }
 
+#define __HAVE_PREBOOT_ARCH_MEMSET
+
 void *memset(void *s, int c, size_t n)
 {
 	char *xs;

@@ -82,25 +84,6 @@ void *memset(void *s, int c, size_t n)
 	return s;
 }
 
-void *memcpy(void *__dest, __const void *__src, size_t __n)
-{
-	return __builtin_memcpy(__dest, __src, __n);
-}
-
-void *memmove(void *__dest, __const void *__src, size_t __n)
-{
-	char *d;
-	const char *s;
-
-	if (__dest <= __src)
-		return __builtin_memcpy(__dest, __src, __n);
-	d = __dest + __n;
-	s = __src + __n;
-	while (__n--)
-		*--d = *--s;
-	return __dest;
-}
-
 static void error(char *x)
 {
 	unsigned long long psw = 0x000a0000deadbeefULL;

@@ -166,3 +149,5 @@ unsigned long decompress_kernel(void)
 	return (unsigned long) output;
 }
 
+#include "../../../../lib/boot/mem.c"
+

@@ -75,14 +75,7 @@ int puts(const char *s)
 	return 0;
 }
 
-void* memset(void* s, int c, size_t n)
-{
-	int i;
-	char *ss = (char*)s;
-
-	for (i=0;i<n;i++) ss[i] = c;
-	return s;
-}
+#define __HAVE_PREBOOT_ARCH_MEMCPY
 
 void* memcpy(void* __dest, __const void* __src,
 			    size_t __n)

@@ -136,3 +129,5 @@ void decompress_kernel(void)
 	cache_control(CACHE_DISABLE);
 	puts("Ok, booting the kernel.\n");
 }
+
+#include "../../../../lib/boot/mem.c"

@@ -224,45 +224,6 @@ void __putstr(int error, const char *s)
 	outb(0xff & (pos >> 1), vidport+1);
 }
 
-void *memset(void *s, int c, size_t n)
-{
-	int i;
-	char *ss = s;
-
-	for (i = 0; i < n; i++)
-		ss[i] = c;
-	return s;
-}
-#ifdef CONFIG_X86_32
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	int d0, d1, d2;
-	asm volatile(
-		"rep ; movsl\n\t"
-		"movl %4,%%ecx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#else
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	long d0, d1, d2;
-	asm volatile(
-		"rep ; movsq\n\t"
-		"movq %4,%%rcx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#endif
-
 static void error(char *x)
 {
 	__putstr(1, "\n\n");

@@ -1,5 +1,7 @@
 #include "misc.h"
 
+#define __HAVE_PREBOOT_ARCH_MEMCMP
+
 int memcmp(const void *s1, const void *s2, size_t len)
 {
 	u8 diff;

@@ -8,4 +10,37 @@ int memcmp(const void *s1, const void *s2, size_t len)
 	return diff;
 }
 
+#define __HAVE_PREBOOT_ARCH_MEMCPY
+
+#ifdef CONFIG_X86_32
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	int d0, d1, d2;
+	asm volatile(
+		"rep ; movsl\n\t"
+		"movl %4,%%ecx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#else
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	long d0, d1, d2;
+	asm volatile(
+		"rep ; movsq\n\t"
+		"movq %4,%%rcx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#endif
+
+#include "../../../../lib/boot/mem.c"
 #include "../string.c"

@@ -0,0 +1,58 @@
+/*
+ * Small subset of simple memory helper functions required by different
+ * compressors for preboot environment.
+ */
+
+#include <linux/string.h>
+
+#ifndef __HAVE_PREBOOT_ARCH_MEMCPY
+void *memcpy(void *__dest, __const void *__src, size_t __n)
+{
+	return __builtin_memcpy(__dest, __src, __n);
+}
+#endif
+
+#ifndef __HAVE_PREBOOT_ARCH_MEMMOVE
+void *memmove(void *__dest, __const void *__src, size_t count)
+{
+	unsigned char *d = __dest;
+	const unsigned char *s = __src;
+
+	if (__dest = __src)
+		return __dest;
+
+	if (__dest < __src)
+		return memcpy(__dest, __src, count);
+
+	while (count--)
+		d[count] = s[count];
+	return __dest;
+}
+#endif
+
+#ifndef __HAVE_PREBOOT_ARCH_MEMCMP
+int memcmp(const void *cs, const void *ct, size_t count)
+{
+	const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
+	int res = 0;
+
+	while (su1 < end) {
+		res = *su1++ - *su2++;
+		if (res)
+			break;
+	}
+	return res;
+}
+#endif
+
+#ifndef __HAVE_PREBOOT_ARCH_MEMSET
+void *memset(void *s, int c, size_t count)
+{
+	char *xs = s;
+
+	while (count--)
+		*xs++ = c;
+	return s;
+}
+#endif
+

@@ -160,76 +160,10 @@
 #define vfree(ptr) do { if (ptr != NULL) free(ptr); } while (0)
 
 /*
- * FIXME: Not all basic memory functions are provided in architecture-specific
- * files (yet). We define our own versions here for now, but this should be
- * only a temporary solution.
- *
- * memeq and memzero are not used much and any remotely sane implementation
- * is fast enough. memcpy/memmove speed matters in multi-call mode, but
- * the kernel image is decompressed in single-call mode, in which only
- * memcpy speed can matter and only if there is a lot of uncompressible data
- * (LZMA2 stores uncompressible chunks in uncompressed form). Thus, the
- * functions below should just be kept small; it's probably not worth
- * optimizing for speed.
+ * To support XZ-decompressed file in preboot environment, include the file
+ * lib/boot/mem.c, to bring in all the required memory helper functions.
  */
 
-#ifndef memeq
-static bool memeq(const void *a, const void *b, size_t size)
-{
-	const uint8_t *x = a;
-	const uint8_t *y = b;
-	size_t i;
-
-	for (i = 0; i < size; ++i)
-		if (x[i] != y[i])
-			return false;
-
-	return true;
-}
-#endif
-
-#ifndef memzero
-static void memzero(void *buf, size_t size)
-{
-	uint8_t *b = buf;
-	uint8_t *e = b + size;
-
-	while (b != e)
-		*b++ = '\0';
-}
-#endif
-
-#ifndef memmove
-/* Not static to avoid a conflict with the prototype in the Linux headers. */
-void *memmove(void *dest, const void *src, size_t size)
-{
-	uint8_t *d = dest;
-	const uint8_t *s = src;
-	size_t i;
-
-	if (d < s) {
-		for (i = 0; i < size; ++i)
-			d[i] = s[i];
-	} else if (d > s) {
-		i = size;
-		while (i-- > 0)
-			d[i] = s[i];
-	}
-
-	return dest;
-}
-#endif
-
-/*
- * Since we need memmove anyway, would use it as memcpy too.
- * Commented out for now to avoid breaking things.
- */
-/*
-#ifndef memcpy
-#	define memcpy memmove
-#endif
-*/
-
 #include "xz/xz_crc32.c"
 #include "xz/xz_dec_stream.c"
 #include "xz/xz_dec_lzma2.c"

@@ -37,9 +37,12 @@
 #		ifdef CONFIG_XZ_DEC_SPARC
 #			define XZ_DEC_SPARC
 #		endif
-#		define memeq(a, b, size) (memcmp(a, b, size) = 0)
-#		define memzero(buf, size) memset(buf, 0, size)
 #	endif
+	/* Make all environments, including preboot, use memcmp for memeq */
+#	define memeq(a, b, size) (memcmp(a, b, size) = 0)
+	/* To suppress redefine warning in some architecture's preboot */
+#	undef memzero
+#	define memzero(buf, size) memset(buf, 0, size)
 #	define get_le32(p) le32_to_cpup((const uint32_t *)(p))
 #else
 	/*