Re: [PATCH] blk: use REQ_OP_WRITE instead of hard code

[Johannes Thumshirn]

On 19/10/2020 16:06, Hui Su wrote:
> use REQ_OP_WRITE instead of hard code in
> op_is_write().
> 
> Signed-off-by: Hui Su <sh_def@xxxxxxx>
> ---
>  include/linux/blk_types.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
> index 7d7c13238fdb..7b9b02378c24 100644
> --- a/include/linux/blk_types.h
> +++ b/include/linux/blk_types.h
> @@ -440,7 +440,7 @@ static inline void bio_set_op_attrs(struct bio *bio, unsigned op,
>  
>  static inline bool op_is_write(unsigned int op)
>  {
> -	return (op & 1);
> +	return (op & REQ_OP_WRITE);

op_is_write() returns true for every req_op that writes to a device (they all have 
the lowest bit set), while REQ_OP_WRITE means a WRITE. You'll change the semantics
with this patch.