Re: [PATCH 13/17] watch_queue: Implement mount topology and attribute change notifications [ver #5]

From: David Howells
Date: Fri Jul 24 2020 - 06:20:13 EST


David Howells <dhowells@xxxxxxxxxx> 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, so
we're currently limited to ~2 billion concurrent mounts:-/

David