Re: file metadata via fs API

From: David Howells
Date: Wed Aug 12 2020 - 09:06:41 EST

Miklos Szeredi <miklos@xxxxxxxxxx> wrote:

> That presumably means the mount ID <-> mount path mapping already
> exists, which means it's just possible to use the open(mount_path,
> O_PATH) to obtain the base fd.

No, you can't. A path more correspond to multiple mounts stacked on top of
each other, e.g.:

mount -t tmpfs none /mnt
mount -t tmpfs none /mnt
mount -t tmpfs none /mnt

Now you have three co-located mounts and you can't use the path to
differentiate them. I think this might be an issue in autofs, but Ian would
need to comment on that.