From 152382af4056aadc0c2ea2e8e8258b277be085bf Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Thu, 21 Aug 2008 19:46:37 +0200 Subject: [PATCH] [S390] fix ext2_find_next_bit ext4 does not work on s390 because ext2_find_next_bit is broken. Fortunately this function is only used by ext4. The function uses ffs which does not work analog to ffz. The result of ffs has an offset of 1 which is not taken into account. To fix this use the low level __ffs_word function directly instead of the ill defined ffs. In addition the patch improves find_next_zero_bit and ext2_find_next_zero_bit by passing the bit offset into __ffz_word instead of adding it after the function call returned. Signed-off-by: Eric Sandeen Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/bitops.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h index b4eb24ab5af9..8e9243ae0c19 100644 --- a/arch/s390/include/asm/bitops.h +++ b/arch/s390/include/asm/bitops.h @@ -709,7 +709,7 @@ static inline int find_next_zero_bit (const unsigned long * addr, * __ffz_word returns __BITOPS_WORDSIZE * if no zero bit is present in the word. */ - set = __ffz_word(0, *p >> bit) + bit; + set = __ffz_word(bit, *p >> bit); if (set >= size) return size + offset; if (set < __BITOPS_WORDSIZE) @@ -824,7 +824,7 @@ static inline int ext2_find_next_zero_bit(void *vaddr, unsigned long size, * s390 version of ffz returns __BITOPS_WORDSIZE * if no zero bit is present in the word. */ - set = ffz(__load_ulong_le(p, 0) >> bit) + bit; + set = __ffz_word(bit, __load_ulong_le(p, 0) >> bit); if (set >= size) return size + offset; if (set < __BITOPS_WORDSIZE) @@ -865,7 +865,7 @@ static inline int ext2_find_next_bit(void *vaddr, unsigned long size, * s390 version of ffz returns __BITOPS_WORDSIZE * if no zero bit is present in the word. */ - set = ffs(__load_ulong_le(p, 0) >> bit) + bit; + set = __ffs_word(0, __load_ulong_le(p, 0) & (~0UL << bit)); if (set >= size) return size + offset; if (set < __BITOPS_WORDSIZE) -- 2.20.1