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From:   David Howells <dhowells@redhat.com>
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Subject: Re: [PATCH 13/17] watch_queue: Implement mount topology and attribute change notifications [ver #5]
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Date:   Fri, 24 Jul 2020 11:19:59 +0100
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David Howells <dhowells@redhat.com> wrote:

> > What guarantees that mount_id is going to remain a 32bit entity?
> =

> You think it likely we'd have >4 billion concurrent mounts on a system? =
 That
> would require >1.2TiB of RAM just for the struct mount allocations.
> =

> But I can expand it to __u64.

That said, sys_name_to_handle_at() assumes it's a 32-bit signed integer, s=
o
we're currently limited to ~2 billion concurrent mounts:-/

David