[dm-devel] split scsi passthrough fields out of struct request V2

[Jens Axboe]

On 01/26/2017 01:47 PM, Bart Van Assche wrote:
> On 01/26/2017 11:01 AM, Jens Axboe wrote:
>> On 01/26/2017 11:59 AM, hch at lst.de wrote:
>>> On Thu, Jan 26, 2017 at 11:57:36AM -0700, Jens Axboe wrote:
>>>> It's against my for-4.11/block, which you were running under Christoph's
>>>> patches. Maybe he's using an older version? In any case, should be
>>>> pretty trivial for you to hand apply. Just ensure that .flags is set to
>>>> 0 for the common cases, and inherit 'flags' when it is passed in.
>>>
>>> No, the flush op cleanups you asked for last round create a conflict
>>> with your patch.  They should be trivial to fix, though.
>>
>> Ah, makes sense. And yes, as I said, should be trivial to hand apply the
>> hunk that does fail.
> 
> Hello Jens and Christoph,
> 
> With the below patch applied the test got a little further but did not
> pass unfortunately. I tried to analyze the new call stack but it's not yet
> clear to me what is going on.
>  
> The patch I had applied on Christoph's tree:
> 
> ---
>  block/blk-mq-sched.c | 2 +-
>  block/blk-mq.c       | 6 +++---
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
> index 3bd66e50ec84..7c9318755fab 100644
> --- a/block/blk-mq-sched.c
> +++ b/block/blk-mq-sched.c
> @@ -116,7 +116,7 @@ struct request *blk_mq_sched_get_request(struct request_queue *q,
>  	ctx = blk_mq_get_ctx(q);
>  	hctx = blk_mq_map_queue(q, ctx->cpu);
>  
> -	blk_mq_set_alloc_data(data, q, 0, ctx, hctx);
> +	blk_mq_set_alloc_data(data, q, data->flags, ctx, hctx);
>  
>  	if (e) {
>  		data->flags |= BLK_MQ_REQ_INTERNAL;
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 83640869d9e4..6697626e5d32 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -248,7 +248,7 @@ EXPORT_SYMBOL_GPL(__blk_mq_alloc_request);
>  struct request *blk_mq_alloc_request(struct request_queue *q, int rw,
>  		unsigned int flags)
>  {
> -	struct blk_mq_alloc_data alloc_data;
> +	struct blk_mq_alloc_data alloc_data = { .flags = flags };
>  	struct request *rq;
>  	int ret;
>  
> @@ -1369,7 +1369,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
>  {
>  	const int is_sync = op_is_sync(bio->bi_opf);
>  	const int is_flush_fua = op_is_flush(bio->bi_opf);
> -	struct blk_mq_alloc_data data;
> +	struct blk_mq_alloc_data data = { };
>  	struct request *rq;
>  	unsigned int request_count = 0, srcu_idx;
>  	struct blk_plug *plug;
> @@ -1491,7 +1491,7 @@ static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio)
>  	const int is_flush_fua = op_is_flush(bio->bi_opf);
>  	struct blk_plug *plug;
>  	unsigned int request_count = 0;
> -	struct blk_mq_alloc_data data;
> +	struct blk_mq_alloc_data data = { };
>  	struct request *rq;
>  	blk_qc_t cookie;
>  	unsigned int wb_acct;

Looks correct to me. Your call path has blk_get_request() in it, I don't have
that in my tree. Is it passing in the right mask?

-- 
Jens Axboe