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Date:   Thu, 20 Jul 2023 15:25:18 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     David Sterba <dsterba@suse.cz>
Cc:     Christoph Hellwig <hch@lst.de>, Chris Mason <clm@fb.com>,
        Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>,
        Matthew Wilcox <willy@infradead.org>,
        linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 01/23] btrfs: pass a flags argument to cow_file_range
Message-ID: <20230720132518.GA14692@lst.de>
References: <20230628153144.22834-1-hch@lst.de> <20230628153144.22834-2-hch@lst.de> <20230720112236.GW20457@twin.jikos.cz>
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On Thu, Jul 20, 2023 at 01:22:36PM +0200, David Sterba wrote:
> On Wed, Jun 28, 2023 at 05:31:22PM +0200, Christoph Hellwig wrote:
> > The int used as bool unlock is not a very good way to describe the
> > behavior, and the next patch will have to add another beahvior modifier.
> > Switch to pass a flag instead, with an inital CFR_KEEP_LOCKED flag that
> > specifies the pages should always be kept locked.  This is the inverse
> > of the old unlock argument for the reason that it requires a flag for
> > the exceptional behavior.
> 
> Int is the wrong type but I'm not sure that for two flags we should use
> a bit flags. Two bool parameters are IMHO fine and "CFR" does not mean
> anything, it's really only relevant for the function.

CFR stands for cow_file_range.  The good news is that with my
(huge) stack of pending pages both flags will eventually go away.
The bad news is that for an intermediate change I actually need a third
one.