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Date:   Fri, 7 Jul 2023 15:13:06 +0200
From:   Jan Kara <jack@suse.cz>
To:     Kent Overstreet <kent.overstreet@linux.dev>
Cc:     "Darrick J. Wong" <djwong@kernel.org>,
        Josef Bacik <josef@toxicpanda.com>,
        torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-bcachefs@vger.kernel.org,
        dchinner@redhat.com, sandeen@redhat.com, willy@infradead.org,
        tytso@mit.edu, bfoster@redhat.com, jack@suse.cz,
        andreas.gruenbacher@gmail.com, brauner@kernel.org,
        peterz@infradead.org, akpm@linux-foundation.org,
        dhowells@redhat.com
Subject: Re: [GIT PULL] bcachefs
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On Thu 06-07-23 18:43:14, Kent Overstreet wrote:
> On Thu, Jul 06, 2023 at 02:19:14PM -0700, Darrick J. Wong wrote:
> > /me shrugs, been on vacation and in hospitals for the last month or so.
> > 
> > >      bcachefs doesn't use sget() for mutual exclusion because a) sget()
> > >      is insane, what we really want is the _block device_ to be opened
> > >      exclusively (which we do), and we have our own block device opening
> > >      path - which we need to, as we're a multi device filesystem.
> > 
> > ...and isn't jan kara already messing with this anyway?
> 
> The blkdev_get_handle() patchset? I like that, but I don't think that's
> related - if there's something more related to sget() I haven't seen it
> yet

There's a series on top of that that also modifies how sget() works [1].
Christian wants that bit to be merged separately from the bdev handle stuff
and Christoph chimed in with some other related cleanups so he'll now take
care of that change.

Anyhow we should have sget() that does not exclusively claim the bdev
unless it needs to create a new superblock soon.

								Honza

[1] https://lore.kernel.org/all/20230704125702.23180-6-jack@suse.cz

-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR