'Adding' a writable proc file under /proc/net/afs/ [was [PATCH 3/3] afs: Implement namespacing]

From: David Howells
Date: Tue May 15 2018 - 13:39:35 EST


Christoph Hellwig <hch@xxxxxx> wrote:

> So the real question here is why afs needs a write callback as the first
> user of /proc/net ever in a day and time were we've deprecated adding
> new proc files. This is a discussion that should be had with linux-fsdevel
> and netdev in Cc.

/proc/fs/afs/cells and /proc/fs/afs/rootcell are not new proc files, nor is
the ability to configure the in-kernel afs filesystem by writing to them new.
The cells file has been there since 2002 and the rootcell file before the
start of the git history in 2005 - it's just that they've been in
/proc/fs/afs/ not /proc/net/afs/.

However, the afs procfiles need to be somewhere under /proc/net/ for the
network namespacing, so I moved the directory over and emplaced a symlink at
/proc/fs/afs.

David