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Subject: Re: [PATCH 1/6] scsi: libsas: Add sas_task_find_rq()
To:     John Garry <john.garry@huawei.com>, <jejb@linux.ibm.com>,
        <martin.petersen@oracle.com>, <jinpu.wang@cloud.ionos.com>,
        <damien.lemoal@wdc.com>
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        <linux-kernel@vger.kernel.org>, <linuxarm@huawei.com>,
        <ipylypiv@google.com>, <changyuanl@google.com>, <hch@lst.de>
References: <1664368034-114991-1-git-send-email-john.garry@huawei.com>
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 <e47fe754-c8a7-99ff-88f2-8b09d98306ab@huawei.com>
 <e264e099-8492-5ba5-ae66-4c71c146ba22@huawei.com>
From:   Jason Yan <yanaijie@huawei.com>
Message-ID: <cad2134a-5b25-963c-592a-45c49fdcfc66@huawei.com>
Date:   Wed, 28 Sep 2022 22:38:59 +0800
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On 2022/9/28 21:50, John Garry wrote:
> On 28/09/2022 14:13, Jason Yan wrote:
>>> +++ b/include/scsi/libsas.h
>>> @@ -644,6 +644,28 @@ static inline bool sas_is_internal_abort(struct 
>>> sas_task *task)
>>>       return task->task_proto == SAS_PROTOCOL_INTERNAL_ABORT;
>>>   }
>>> +static inline struct request *sas_task_find_rq(struct sas_task *task)
>>> +{
>>> +    struct scsi_cmnd *scmd;
>>> +
>>> +    if (!task || !task->uldd_task)
>>> +        return NULL;
>>> +
>>> +    if (task->task_proto & SAS_PROTOCOL_STP_ALL) {
>>> +        struct ata_queued_cmd *qc;
>>> +
>>> +        qc = task->uldd_task;
>>> +        scmd = qc->scsicmd;
>>
>> Can we remove that local qc?
>>
> 
> We could...
> 
>> and
>>      scmd = ((struct ata_queued_cmd *)task->uldd_task)->scsicmd;
> 
> ... but I am not really sure that this is much better, specifically 
> because of the casting from void. If you feel really strongly about it I 
> could.
> 

There are plenty of examples in the kernel, and in scsi itself. Such as

#define fc_host_node_name(x) \
	(((struct fc_host_attrs *)(x)->shost_data)->node_name)


> thanks,
> John
> .