Re: [PATCH 1/2] block: export __blk_complete_request

[jianchao.wang]

Hi Christoph

Thanks for your kindly response.
The patch I posted ('scsi_transport_fc: use __blk_complete_request in fc_bsg_job_timeout')
is just based on code review. I don't have actual issue on it. :)

Thanks
Jianchao

On 06/19/2018 10:09 PM, Christoph Hellwig wrote:
> Does the patch below fix your FC issue?
> 
> ---
>>From 5e5b4fc51c84a0f5c27f2f770be7a4eaed0f6e8c Mon Sep 17 00:00:00 2001
> From: Christoph Hellwig <hch@xxxxxx>
> Date: Tue, 19 Jun 2018 13:59:52 +0200
> Subject: block: fix timeout changes for legacy request drivers
> 
> blk_mq_complete_request can only be called for blk-mq drivers, but when
> removing the BLK_EH_HANDLED return value, two legacy request timeout
> methods incorrectly got switched to call blk_mq_complete_request.
> Call __blk_complete_request instead to reinstance the previous behavior.
> For that __blk_complete_request needs to be exported.
> 
> Fixes: 1fc2b62e ("scsi_transport_fc: complete requests from ->timeout")
> Fixes: 0df0bb08 ("null_blk: complete requests from ->timeout")
> Reported-by: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
>  block/blk-softirq.c              | 1 +
>  drivers/block/null_blk.c         | 2 +-
>  drivers/scsi/scsi_transport_fc.c | 2 +-
>  3 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/block/blk-softirq.c b/block/blk-softirq.c
> index 01e2b353a2b9..15c1f5e12eb8 100644
> --- a/block/blk-softirq.c
> +++ b/block/blk-softirq.c
> @@ -144,6 +144,7 @@ void __blk_complete_request(struct request *req)
>  
>  	local_irq_restore(flags);
>  }
> +EXPORT_SYMBOL(__blk_complete_request);
>  
>  /**
>   * blk_complete_request - end I/O on a request
> diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
> index 7948049f6c43..042c778e5a4e 100644
> --- a/drivers/block/null_blk.c
> +++ b/drivers/block/null_blk.c
> @@ -1365,7 +1365,7 @@ static blk_qc_t null_queue_bio(struct request_queue *q, struct bio *bio)
>  static enum blk_eh_timer_return null_rq_timed_out_fn(struct request *rq)
>  {
>  	pr_info("null: rq %p timed out\n", rq);
> -	blk_mq_complete_request(rq);
> +	__blk_complete_request(rq);
>  	return BLK_EH_DONE;
>  }
>  
> diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
> index 1da3d71e9f61..13948102ca29 100644
> --- a/drivers/scsi/scsi_transport_fc.c
> +++ b/drivers/scsi/scsi_transport_fc.c
> @@ -3592,7 +3592,7 @@ fc_bsg_job_timeout(struct request *req)
>  
>  	/* the blk_end_sync_io() doesn't check the error */
>  	if (inflight)
> -		blk_mq_complete_request(req);
> +		__blk_complete_request(req);
>  	return BLK_EH_DONE;
>  }
>  
>