[PATCH] crc32: replace bitreverse by bitrev32
This patch replaces bitreverse() by bitrev32. The only users of bitreverse()
are crc32 itself and via-velocity.
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c
index 74f8947..4587f23 100644
--- a/drivers/net/via-velocity.c
+++ b/drivers/net/via-velocity.c
@@ -3132,7 +3132,7 @@
}
/* Finally, invert the result once to get the correct data */
crc = ~crc;
- return bitreverse(crc) >> 16;
+ return bitrev32(crc) >> 16;
}
/**
diff --git a/include/linux/crc32.h b/include/linux/crc32.h
index 56c0645..e20dd1f 100644
--- a/include/linux/crc32.h
+++ b/include/linux/crc32.h
@@ -6,10 +6,10 @@
#define _LINUX_CRC32_H
#include <linux/types.h>
+#include <linux/bitrev.h>
extern u32 crc32_le(u32 crc, unsigned char const *p, size_t len);
extern u32 crc32_be(u32 crc, unsigned char const *p, size_t len);
-extern u32 bitreverse(u32 in);
#define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)data, length)
@@ -21,7 +21,7 @@
* is in bit nr 0], thus it must be reversed before use. Except for
* nics that bit swap the result internally...
*/
-#define ether_crc(length, data) bitreverse(crc32_le(~0, data, length))
+#define ether_crc(length, data) bitrev32(crc32_le(~0, data, length))
#define ether_crc_le(length, data) crc32_le(~0, data, length)
#endif /* _LINUX_CRC32_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index 0d68355..47b172d 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -26,6 +26,7 @@
config CRC32
tristate "CRC32 functions"
default y
+ select BITREVERSE
help
This option is provided for the case where no in-kernel-tree
modules require CRC32 functions, but a module built outside the
diff --git a/lib/crc32.c b/lib/crc32.c
index 285fd9b..bfc3331 100644
--- a/lib/crc32.c
+++ b/lib/crc32.c
@@ -235,23 +235,8 @@
}
#endif
-/**
- * bitreverse - reverse the order of bits in a u32 value
- * @x: value to be bit-reversed
- */
-u32 bitreverse(u32 x)
-{
- x = (x >> 16) | (x << 16);
- x = (x >> 8 & 0x00ff00ff) | (x << 8 & 0xff00ff00);
- x = (x >> 4 & 0x0f0f0f0f) | (x << 4 & 0xf0f0f0f0);
- x = (x >> 2 & 0x33333333) | (x << 2 & 0xcccccccc);
- x = (x >> 1 & 0x55555555) | (x << 1 & 0xaaaaaaaa);
- return x;
-}
-
EXPORT_SYMBOL(crc32_le);
EXPORT_SYMBOL(crc32_be);
-EXPORT_SYMBOL(bitreverse);
/*
* A brief CRC tutorial.
@@ -400,10 +385,7 @@
static void bytereverse(unsigned char *buf, size_t len)
{
while (len--) {
- unsigned char x = *buf;
- x = (x >> 4) | (x << 4);
- x = (x >> 2 & 0x33) | (x << 2 & 0xcc);
- x = (x >> 1 & 0x55) | (x << 1 & 0xaa);
+ unsigned char x = bitrev8(*buf);
*buf++ = x;
}
}
@@ -460,11 +442,11 @@
/* Now swap it around for the other test */
bytereverse(buf, len + 4);
- init = bitreverse(init);
- crc2 = bitreverse(crc1);
- if (crc1 != bitreverse(crc2))
+ init = bitrev32(init);
+ crc2 = bitrev32(crc1);
+ if (crc1 != bitrev32(crc2))
printf("\nBit reversal fail: 0x%08x -> 0x%08x -> 0x%08x\n",
- crc1, crc2, bitreverse(crc2));
+ crc1, crc2, bitrev32(crc2));
crc1 = crc32_le(init, buf, len);
if (crc1 != crc2)
printf("\nCRC endianness fail: 0x%08x != 0x%08x\n", crc1,
