Commit 12fc760f authored Feb 25, 2013 by Changman Lee Committed by Jaegeuk Kim Mar 08, 2013

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>

parent 47b3bc90

fs/f2fs/segment.h

+1 −2

Original line number	Diff line number	Diff line
		@@ -464,8 +464,7 @@ static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi, int freed)

		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);
		}

		/*

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