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Date:   Mon, 25 Apr 2022 11:22:48 +0200
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Subject: Re: [PATCH 1/4] scsi: core: constify pointer to scsi_host_template
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To:     John Garry <john.garry@huawei.com>,
        Christoph Hellwig <hch@infradead.org>
Cc:     "Ewan D. Milne" <emilne@redhat.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Avri Altman <avri.altman@wdc.com>,
        Doug Gilbert <dgilbert@interlog.com>,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        james.smart@broadcom.com
References: <20220408103027.311624-1-krzysztof.kozlowski@linaro.org>
 <2a88a992-641a-b3ff-fe39-7a61fff87cb6@huawei.com>
 <4c3be5b6-50ef-9e9a-6cee-9642df943342@linaro.org>
 <7b3885e3-dbae-ff0b-21dc-c28d635d950b@huawei.com>
 <c121430b1b5c8f5816b2b42b9178d00889260c90.camel@redhat.com>
 <b6af3fe8-db9a-b5dc-199f-21c05d7664a2@huawei.com>
 <Yl+wJ7xSHzWmR+bR@infradead.org>
 <d09faf74-a52e-8d93-cf26-08b43b12c564@huawei.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <d09faf74-a52e-8d93-cf26-08b43b12c564@huawei.com>
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On 25/04/2022 10:58, John Garry wrote:
> On 20/04/2022 08:03, Christoph Hellwig wrote:
>>> The standard flow is:
>>>
>>> shost = scsi_host_alloc(sht, )
>>>
>>> // modify shost, like
>>> shost->cmd_per_lun = 5;
>>>
>>> scsi_add_host(shost)
>>>
>>> Is there some reason for which those two drivers can't follow that?
>> I think they should.  Method tables should not be mutable data.
>> .
> 
> Hi Krzysztof,
> 
> Do you have any interest in going further with your work and trying to 
> change all SCSI driver instances of scsi_host_template to be const? I am 
> not sure if it has been attempted before...

I can work on this, but what about the SCSI core modifying the template?
For example scsi_proc_hostdir_rm(): 'present' and 'proc_dir' members.
Where should they be stored? Should they be moved to the Scsi_Host?


Best regards,
Krzysztof