Re: [PATCH] mq-deadline: Make sure to always unlock zones

[Jens Axboe <axboe@kernel.dk>]

On 2/28/18 10:35 AM, Bart Van Assche wrote:
> From: Damien Le Moal <damien.lemoal@wdc.com>
> 
> In case of a failed write request (all retries failed) and when using
> libata, the SCSI error handler calls scsi_finish_command(). In the
> case of blk-mq this means that scsi_mq_done() does not get called,
> that blk_mq_complete_request() does not get called and also that the
> mq-deadline .completed_request() method is not called. This results in
> the target zone of the failed write request being left in a locked
> state, preventing that any new write requests are issued to the same
> zone.
> 
> Fix this by replacing the .completed_request() method with the
> .finish_request() method as this method is always called whether or
> not a request completes successfully. Since the .finish_request()
> method is only called by the blk-mq core if a .prepare_request()
> method exists, add a dummy .prepare_request() method.

Thanks, applied for 4.16.

-- 
Jens Axboe