Re: [PATCH 0/4] autofs4 - autofs needs a miscelaneous device for ioctls

[Andrew Morton <akpm@linux-foundation.org>]

On Tue, 26 Feb 2008 12:21:58 +0900 (WST) Ian Kent <raven@themaw.net> wrote:

> 
> Hi Andrew,
> 
> There is a problem with active restarts in autofs (that is to
> say restarting autofs when there are busy mounts).
> 
> Currently autofs uses "umount -l" to clear active mounts at
> restart. While using lazy umount works for most cases, anything
> that needs to walk back up the mount tree to construct a path,
> such as getcwd(2) and the proc file system /proc/<pid>/cwd, no
> longer works because the point from which the path is constructed
> has been detached from the mount tree.
> 
> The actual problem with autofs is that it can't reconnect to
> existing mounts. Immediately one things of just adding the
> ability to remount autofs file systems would solve it, but
> alas, that can't work. This is because autofs direct mounts
> and the implementation of "on demand mount and expire" of
> nested mount trees have the file system mounted on top of
> the mount trigger dentry.
> 
> To resolve this a miscellaneous device node for routing ioctl
> commands to these mount points has been implemented for the
> autofs4 kernel module.
> 
> For those wishing to test this out an updated user space daemon
> is needed. Checking out and building from the git repo or
> applying all the current patches to the 5.0.3 tar distribution
> will do the trick. This is all available at the usual location
> on kernel.org.
> 

Could we please be a bit more specific than "the usual location"?

Should autofs userspace have an entry in Documentation/Changes?