From: Yury Norov <yury.norov@xxxxxxxxx> commit d5767057c9a76a29f073dad66b7fa12a90e8c748 upstream. ext2_swab() is defined locally in lib/find_bit.c However it is not specific to ext2, neither to bitmaps. There are many potential users of it, so rename it to just swab() and move to include/uapi/linux/swab.h ABI guarantees that size of unsigned long corresponds to BITS_PER_LONG, therefore drop unneeded cast. Link: http://lkml.kernel.org/r/20200103202846.21616-1-yury.norov@xxxxxxxxx Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> Cc: Allison Randal <allison@xxxxxxxxxxx> Cc: Joe Perches <joe@xxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: William Breathitt Gray <vilhelm.gray@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/swab.h | 1 + include/uapi/linux/swab.h | 10 ++++++++++ lib/find_bit.c | 16 ++-------------- 3 files changed, 13 insertions(+), 14 deletions(-) --- a/include/linux/swab.h +++ b/include/linux/swab.h @@ -7,6 +7,7 @@ # define swab16 __swab16 # define swab32 __swab32 # define swab64 __swab64 +# define swab __swab # define swahw32 __swahw32 # define swahb32 __swahb32 # define swab16p __swab16p --- a/include/uapi/linux/swab.h +++ b/include/uapi/linux/swab.h @@ -4,6 +4,7 @@ #include <linux/types.h> #include <linux/compiler.h> +#include <asm/bitsperlong.h> #include <asm/swab.h> /* @@ -132,6 +133,15 @@ static inline __attribute_const__ __u32 __fswab64(x)) #endif +static __always_inline unsigned long __swab(const unsigned long y) +{ +#if BITS_PER_LONG == 64 + return __swab64(y); +#else /* BITS_PER_LONG == 32 */ + return __swab32(y); +#endif +} + /** * __swahw32 - return a word-swapped 32-bit value * @x: value to wordswap --- a/lib/find_bit.c +++ b/lib/find_bit.c @@ -149,18 +149,6 @@ EXPORT_SYMBOL(find_last_bit); #ifdef __BIG_ENDIAN -/* include/linux/byteorder does not support "unsigned long" type */ -static inline unsigned long ext2_swab(const unsigned long y) -{ -#if BITS_PER_LONG == 64 - return (unsigned long) __swab64((u64) y); -#elif BITS_PER_LONG == 32 - return (unsigned long) __swab32((u32) y); -#else -#error BITS_PER_LONG not defined -#endif -} - #if !defined(find_next_bit_le) || !defined(find_next_zero_bit_le) static inline unsigned long _find_next_bit_le(const unsigned long *addr1, const unsigned long *addr2, unsigned long nbits, @@ -177,7 +165,7 @@ static inline unsigned long _find_next_b tmp ^= invert; /* Handle 1st word. */ - tmp &= ext2_swab(BITMAP_FIRST_WORD_MASK(start)); + tmp &= swab(BITMAP_FIRST_WORD_MASK(start)); start = round_down(start, BITS_PER_LONG); while (!tmp) { @@ -191,7 +179,7 @@ static inline unsigned long _find_next_b tmp ^= invert; } - return min(start + __ffs(ext2_swab(tmp)), nbits); + return min(start + __ffs(swab(tmp)), nbits); } #endif