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Date:   Thu, 7 Apr 2022 04:13:47 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     linux-cachefs@redhat.com,
        Rohith Surabattula <rohiths.msft@gmail.com>,
        Steve French <sfrench@samba.org>,
        Shyam Prasad N <nspmangalore@gmail.com>,
        linux-cifs@vger.kernel.org, Jeff Layton <jlayton@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH 14/14] mm, netfs, fscache: Stop read optimisation when
 folio removed from pagecache
Message-ID: <Yk5W6zvvftOB+80D@casper.infradead.org>
References: <164928615045.457102.10607899252434268982.stgit@warthog.procyon.org.uk>
 <164928630577.457102.8519251179327601178.stgit@warthog.procyon.org.uk>
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On Thu, Apr 07, 2022 at 12:05:05AM +0100, David Howells wrote:
> Fix this by adding an extra address_space operation, ->removing folio(),
> and flag, AS_NOTIFY_REMOVING_FOLIO.  The operation is called if the flag is
> set when a folio is removed from the pagecache.  The flag should be set if
> a non-NULL cookie is obtained from fscache and cleared in ->evict_inode()
> before truncate_inode_pages_final() is called.

What's wrong with ->freepage?