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Wong" , Dave Kleikamp , David Sterba , dm-devel@redhat.com, drbd-dev@lists.linbit.com, Gao Xiang , Jack Wang , Jaegeuk Kim , jfs-discussion@lists.sourceforge.net, Joern Engel , Joseph Qi , Kent Overstreet , linux-bcache@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mm@kvack.org, linux-mtd@lists.infradead.org, linux-nfs@vger.kernel.org, linux-nilfs@vger.kernel.org, linux-nvme@lists.infradead.org, linux-pm@vger.kernel.org, linux-raid@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-xfs@vger.kernel.org, "Md. Haris Iqbal" , Mike Snitzer , Minchan Kim , ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, Sergey Senozhatsky , Song Liu , Sven Schnelle , target-devel@vger.kernel.org, Ted Tso , Trond Myklebust , xen-devel@lists.xenproject.org, Jens Axboe , Christian Brauner Subject: Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle Message-ID: References: <20230810171429.31759-1-jack@suse.cz> <20230825015843.GB95084@ZenIV> <20230825134756.o3wpq6bogndukn53@quack3> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230825134756.o3wpq6bogndukn53@quack3> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 9B484160028 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: 3oa66agdmg4oacz8ofbq51ygn5pexoob X-HE-Tag: 1693232580-595558 X-HE-Meta: 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 BDN6bjvU 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Aug 25, 2023 at 03:47:56PM +0200, Jan Kara wrote: > I can see the appeal of not having to introduce the new bdev_handle type > and just using struct file which unifies in-kernel and userspace block > device opens. But I can see downsides too - the last fput() happening from > task work makes me a bit nervous whether it will not break something > somewhere with exclusive bdev opens. Getting from struct file to bdev is > somewhat harder but I guess a helper like F_BDEV() would solve that just > fine. > > So besides my last fput() worry about I think this could work and would be > probably a bit nicer than what I have. But before going and redoing the whole > series let me gather some more feedback so that we don't go back and forth. > Christoph, Christian, Jens, any opinion? I did think about the file a bit. The fact that we'd need something like an anon_file for the by_dev open was always a huge turn off for me, but maybe my concern is overblown. Having a struct file would actually be really useful for a bunch of users.