> Currently autofs has a problem where it won't show the mountpoints of
> non-mounted directories, but I think you would run into that problem too.
> (short version of the problem: how do you prevent 'ls -l' from mounting
> all filesystems in a directory?)
You add the concept of a "light" lookup, and you make path_walk() call this
"light" lookup (be that a separate fs method, or a flag passed down to real
lookup()) iff the path component being looked up is the last component in
the path. A "light" lookup sets a flag in the inode signalling that the inode
is incomplete, so cached_lookup() can check this flag and call a "full"
lookup() (or perhaps a "full" revalidate()) if necessary.
The actual details need to be thought out a bit more, this is only a general
outline. In particular, we need a bullet-proof way to determine when to
"upgrade" the inode from "light" to "full".
You then also need to add a "getdents" kind of message to the autofs
protocol, and a "light lookup" message (which confirms the existence of the
entry, and maybe returns the type of the entry: symlink or directory).
Once all this is done, I'll add support for it in am-utils in a jiffy...
Ion (am-utils co-maintainer)
--
It is better to keep your mouth shut and be thought a fool,
than to open it and remove all doubt.
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