Re: [PATCH 03/22] scsi: add scsi_{get,put}_internal_cmd() helper

[Johannes Thumshirn <Johannes.Thumshirn@xxxxxxx>]

On 02/07/2020 09:59, Hannes Reinecke wrote:
> That's one of the best-kept secrets in the block layer:
> 
> op_is_write()
> 
> The assumption is that every request with a REQ_OP which has the lowest 
> bit set is a write.
> And quite a lot of accounting the the block layer revolves around that.
> So we'll need to keep it.
> 
> ... and we probably should document it somewhere.

I personally find this very obvious:

static inline bool op_is_write(unsigned int op)
{
	return (op & 1);
}