On 08/10/2017 11:15 AM, Goldwyn Rodrigues wrote:
>
>
> On 08/10/2017 09:14 AM, Jens Axboe wrote:
>> On 08/10/2017 05:38 AM, Goldwyn Rodrigues wrote:
>>>
>>>
>>> On 08/09/2017 09:18 PM, Jens Axboe wrote:
>>>> On 08/08/2017 02:36 PM, Jens Axboe wrote:
>>>>> On 08/08/2017 02:32 PM, Shaohua Li wrote:
>>>>>>> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
>>>>>>> index 25f6a0cb27d3..fae021ebec1b 100644
>>>>>>> --- a/include/linux/blkdev.h
>>>>>>> +++ b/include/linux/blkdev.h
>>>>>>> @@ -633,6 +633,7 @@ struct request_queue {
>>>>>>> #define QUEUE_FLAG_REGISTERED 29 /* queue has been registered to a disk */
>>>>>>> #define QUEUE_FLAG_SCSI_PASSTHROUGH 30 /* queue supports SCSI commands */
>>>>>>> #define QUEUE_FLAG_QUIESCED 31 /* queue has been quiesced */
>>>>>>> +#define QUEUE_FLAG_NOWAIT 32 /* stack device driver supports REQ_NOWAIT */
>>>>>
>>>>> Does this work on 32-bit, where sizeof(unsigned long) == 32?
>>>>
>>>> I didn't get an answer to this one.
>>>>
>>>
>>> Oh, I assumed the question is rhetorical.
>>> No, it will not work on 32-bit. I was planning to change the field
>>> queue_flags to u64. Is that okay?
>>
>> No, besides that would not work with set/test_bit() and friends. Grab
>> a free bit instead.
>>
>
> Which bit is free? I don't see any gaps in QUEUE_FLAG_*, and I am not
> sure if any one is unused.
Bit 0 is free in mainline, and I just looked, and two other bits are
gone as well:
http://git.kernel.dk/cgit/linux-block/commit/?h=for-4.14/block&id=e743eb1ecd5564b5ae0a4a76c1566f748a358839
--
Jens Axboe
