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Date:   Tue, 30 May 2023 16:23:36 +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>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 01/16] btrfs: fix range_end calculation in
 extent_write_locked_range
Message-ID: <20230530142336.GA9014@lst.de>
References: <20230523081322.331337-1-hch@lst.de> <20230523081322.331337-2-hch@lst.de> <20230529171318.GI575@twin.jikos.cz> <20230530131304.GP575@twin.jikos.cz>
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On Tue, May 30, 2023 at 03:13:04PM +0200, David Sterba wrote:
> Seems it's directly affecting subpage since e55a0de18572 ("btrfs: rework
> page locking in __extent_writepage()"), the range_end is passed there
> and adjusted by + 1, IOW expecting it to initially have the value of
> 'end'.

This code is only used for compression, which isn't supported for
zoned devices, and for compression, which unless I misremember the code
only supported for multiples of the page size for the allocations.