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From:   Johannes Thumshirn <Johannes.Thumshirn@wdc.com>
To:     John Garry <john.garry@huawei.com>,
        "jejb@linux.ibm.com" <jejb@linux.ibm.com>,
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Subject: Re: [PATCH 1/6] scsi: libsas: Add sas_task_find_rq()
Thread-Topic: [PATCH 1/6] scsi: libsas: Add sas_task_find_rq()
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Date:   Wed, 28 Sep 2022 14:28:57 +0000
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On 28.09.22 15:56, John Garry wrote:=0A=
> On 28/09/2022 14:17, Johannes Thumshirn wrote:=0A=
>>> +static inline struct request *sas_task_find_rq(struct sas_task *task)=
=0A=
>>> +{=0A=
>>> +	struct scsi_cmnd *scmd;=0A=
>>> +=0A=
>>> +	if (!task || !task->uldd_task)=0A=
>>> +		return NULL;=0A=
>> Is anyone actually calling sas_task_find_rq with a NULL task?=0A=
> =0A=
> Yeah, unfortunately. An example - the only one I think - is in the =0A=
> pm8001 driver: pm8001_ccb_alloc() function which takes a task pointer =0A=
> which may be NULL, and this function calls sas_task_find_rq()=0A=
> =0A=
>> That doesn't make a lot of sense from an API POV for me, having=0A=
>> the only argument allowed to be NULL (and not being a *free()=0A=
>> kind of function).=0A=
> =0A=
> I suppose that I could change to only call sas_task_find_rq() for =0A=
> non-NULL sas_task pointers (and remove the task check).=0A=
=0A=
If this is done in only a few drivers I'd go that route TBH.=0A=
=0A=
AFAICS hishi sas doesn't call sas_task_find_rq with a NULL task,=0A=
so it's only pm8001=0A=