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

From: 苏辉
Date: Mon Oct 19 2020 - 10:46:20 EST


Yeah, you are right, thanks for your explanation<br/><br/>Maybe we should define a MASK to do this?
At 2020-10-19 22:09:40, "Johannes Thumshirn" <Johannes.Thumshirn@xxxxxxx> wrote:
>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.