crc32: fix mixing of endian-specific types

crc32.c in its original version freely mixed u32, __le32 and __be32 types
which caused warnings from sparse with __CHECK_ENDIAN__.  This patch fixes
these by forcing the types to u32.

[[email protected]: Minor changelog tweaks]
Signed-off-by: Bob Pearson <[email protected]>
Signed-off-by: Darrick J. Wong <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

lib/crc32.c

@@ -28,13 +28,13 @@
 #include "crc32defs.h"
 
 #if CRC_LE_BITS == 8
-# define tole(x) __constant_cpu_to_le32(x)
+# define tole(x) ((__force u32) __constant_cpu_to_le32(x))
 #else
 # define tole(x) (x)
 #endif
 
 #if CRC_BE_BITS == 8
-# define tobe(x) __constant_cpu_to_be32(x)
+# define tobe(x) ((__force u32) __constant_cpu_to_be32(x))
 #else
 # define tobe(x) (x)
 #endif
@@ -128,9 +128,9 @@ u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len)
 # elif CRC_LE_BITS == 8
 	const u32      (*tab)[] = crc32table_le;
 
-	crc = __cpu_to_le32(crc);
+	crc = (__force u32) __cpu_to_le32(crc);
 	crc = crc32_body(crc, p, len, tab);
-	crc = __le32_to_cpu(crc);
+	crc = __le32_to_cpu((__force __le32)crc);
 #endif
 	return crc;
 }
@@ -171,9 +171,9 @@ u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len)
 # elif CRC_BE_BITS == 8
 	const u32      (*tab)[] = crc32table_be;
 
-	crc = __cpu_to_be32(crc);
+	crc = (__force u32) __cpu_to_be32(crc);
 	crc = crc32_body(crc, p, len, tab);
-	crc = __be32_to_cpu(crc);
+	crc = __be32_to_cpu((__force __be32)crc);
 # endif
 	return crc;
 }