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So make a minor modification by adding (SECTOR_SIZE - 1) before shifting. v3: Remove the rounding stuff. base-commit: 30209debe98b6f66b13591e59e5272cb65b3945e Signed-off-by: Dawei Li Reviewed-by: Christoph Hellwig Reviewed-by: Bart Van Assche Reviewed-by: Chaitanya Kulkarni --- include/linux/blkdev.h | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 57ed49f20d2e..32137d85c9ad 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1349,12 +1349,7 @@ static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, /* assumes size > 256 */ static inline unsigned int blksize_bits(unsigned int size) { - unsigned int bits = 8; - do { - bits++; - size >>= 1; - } while (size > 256); - return bits; + return order_base_2(size >> SECTOR_SHIFT) + SECTOR_SHIFT; } static inline unsigned int block_size(struct block_device *bdev)