f2fs: fix overflow when calculating utilization on 32-bit
Use div_u64 to fix overflow when calculating utilization.
*long int* is 4-bytes on 32-bit so (user blocks * 100) might be
overflow if disk size is over e.g. 512GB.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 552dadb..e399bd4 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -464,8 +464,7 @@
static inline int utilization(struct f2fs_sb_info *sbi)
{
- return (long int)valid_user_blocks(sbi) * 100 /
- (long int)sbi->user_block_count;
+ return div_u64(valid_user_blocks(sbi) * 100, sbi->user_block_count);
}
/*