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Date:   Wed, 20 Jan 2021 17:28:36 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Jan Kara <jack@suse.cz>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-fsdevel@vger.kernel.org,
        Matthew Wilcox <willy@infradead.org>,
        linux-ext4@vger.kernel.org
Subject: Re: [PATCH 2/3] mm: Provide address_space operation for filling
 pages for read
Message-ID: <20210120172836.GA3809508@infradead.org>
References: <20210120160611.26853-1-jack@suse.cz>
 <20210120160611.26853-3-jack@suse.cz>
 <20210120162001.GB3790454@infradead.org>
 <20210120172705.GC24063@quack2.suse.cz>
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On Wed, Jan 20, 2021 at 06:27:05PM +0100, Jan Kara wrote:
> This would mean pulling i_mmap_sem out from ext4/XFS/F2FS private inode
> into the VFS inode. Which is fine by me but it would grow struct inode for
> proc / tmpfs / btrfs (although for btrfs I'm not convinced it isn't
> actually prone to the race and doesn't need similar protection as xfs /
> ext4) so some people may object.

The btrfs folks are already looking into lifting it to common code.

Also I have a patch pending to remove a list_head from the inode to
counter the size increase :)