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From:   David Howells <dhowells@redhat.com>
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To:     Alan Jenkins <alan.christopher.jenkins@gmail.com>
Cc:     dhowells@redhat.com, viro@zeniv.linux.org.uk,
        linux-api@vger.kernel.org, torvalds@linux-foundation.org,
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Subject: Re: [PATCH 01/33] vfs: syscall: Add open_tree(2) to reference or clone a mount [ver #11]
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Date:   Thu, 02 Aug 2018 22:51:58 +0100
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Alan Jenkins <alan.christopher.jenkins@gmail.com> wrote:

> Another closely-related limitation of `mount`, is that it can't atomically set
> the propagation type at mount time.

I want to add a mount_setattr() too at some point:

	fd = open_tree(..., OPEN_TREE_CLONE);
	mount_setattr(fd, ...);
	move_mount(fd, ...);

I'm not sure whether you should be able to fchdir into the cloned tree since
it isn't attached to any mount namespace.

David