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Date:   Wed, 1 Apr 2020 10:43:46 +0200
From:   Karel Zak <kzak@redhat.com>
To:     David Howells <dhowells@redhat.com>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>, dray@redhat.com,
        Miklos Szeredi <mszeredi@redhat.com>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Jeff Layton <jlayton@redhat.com>, Ian Kent <raven@themaw.net>,
        andres@anarazel.de, keyrings@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Lennart Poettering <lennart@poettering.net>,
        Aleksa Sarai <cyphar@cyphar.com>
Subject: Re: Upcoming: Notifications, FS notifications and fsinfo()
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On Tue, Mar 31, 2020 at 10:54:23PM +0100, David Howells wrote:
> Karel Zak <kzak@redhat.com> wrote:
> 
> > - improve fsinfo() to provide set (list) of the attributes by one call
> 
> That would be my preferred way.  I wouldn't want to let the user pin copies of
> state, and I wouldn't want to make open(O_PATH) do it automatically.

You can create cow object on first fsinfo() call, ideally add some
flags to control this behavior -- but you're right, this way is
complicated to implement and possibly dangerous.

I guess return some vector of attributes in one fsinfo() will be good
enough.

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com