From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:48642 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728823AbgDUOSB (ORCPT ); Tue, 21 Apr 2020 10:18:01 -0400 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03LEDwLx130897 for ; Tue, 21 Apr 2020 10:18:01 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 30gfebktf1-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 21 Apr 2020 10:18:00 -0400 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 21 Apr 2020 15:17:06 +0100 References: <20200421061226.33731-1-hch@lst.de> From: Stefan Haberland Subject: Re: stop using ioctl_by_bdev in the s390 DASD driver Date: Tue, 21 Apr 2020 16:17:53 +0200 MIME-Version: 1.0 In-Reply-To: <20200421061226.33731-1-hch@lst.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Content-Language: en-US Message-Id: Sender: linux-s390-owner@vger.kernel.org List-ID: To: Christoph Hellwig , Jan Hoeppner , Jens Axboe , Heiko Carstens , Vasily Gorbik , Christian Borntraeger Cc: linux-s390@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Hi Christoph, thanks for addressing this. But I must say that I do not like this approach. I get your point why you want this ioctl to be removed and I agree with that. Having those implicit partitions at all is really ugly but I fear that this is widely used int the field. So I can not simply remove this code although I would like to. Maybe we find a way to deprecate this. But anyway... Forcing the driver to be build in may have a lot of implications which we should at least have a look at and maybe discuss with the distributors. All major distributions have the driver build as modules and use module parameters in the initrd for example. The second thing is that I do not really like this s390-specific blockdevice operation. I can imagine some ways to get rid of this ioctl_by_bdev. Maybe having a udev rule to add a partition from userspace or having the driver add the implicit partition at the end. Or maybe something else. If it is OK I will have a look at this and discuss this issue with my colleagues and come up with a different approach. Regards, Stefan Am 21.04.20 um 08:12 schrieb Christoph Hellwig: > Hi Jens and DASD maintainers, > > can you take a look at this series, which stops the DASD driver from > issuing ioctls from kernel space, in preparation of removing > ioctl_by_bdev. I don't really like the new s390-only method, but short > of forcing the dasd driver to be built into the kernel I can't think of > anything better. But maybe the s390 maintainers are fine with forcing > the DASD driver to be built in, in which case we could go down that > route?