If a previously used ext2 filesystem with is mounted again then
fallthroughs don't appear to work as expected. Stat returns ENOENT
for these entries.
Can't see anything obviously wrong with the code.
That's an idea, but I guess it won't make everyone happy since it
wastes both disk space and memory.
One of the key differentiators for union mounts concept was that it
doesn't duplicate inodes and dentries from the layers. With the
directory copyup on lookup that's already partially lost, but that can
be justified by the fact that non-directories usually far outnumber
directories.
Another idea is to use an internal inode and make all fallthroughs be
hard links to that.
I think the same would work for whiteouts as well. I don't like the
fact that whiteouts are invisible even when not mounted as part of a
union.
Miklos
--
