[PATCH bpf-next 3/4] bpf: Introduce path iterator

[Song Liu]

On Thu, May 29, 2025 at 10:38 AM Al Viro <viro at zeniv.linux.org.uk> wrote:
>
> On Thu, May 29, 2025 at 09:53:21AM -0700, Song Liu wrote:
>
> > Current version of path iterator only supports walking towards the root,
> > with helper path_parent. But the path iterator API can be extended
> > to cover other use cases.
>
> Clarify the last part, please - call me paranoid, but that sounds like
> a beginning of something that really should be discussed upfront.

We don't have any plan with future use cases yet. The only example
I mentioned in the original version of the commit log is "walk the
mount tree". IOW, it is similar to the current iterator, but skips non
mount point iterations.

Since we call it "path iterator", it might make sense to add ways to
iterate the VFS tree in different patterns. For example, we may
have an iterator that iterates all files within a directory. Again, we
don't see urgent use cases other than the current "walk to root"
iterator.

Thanks,
Song