Linus Torvalds wrote: > > It is not the kernel which decides. The filesystem containing > > /dev/hda/part1 opens "the directory branch". > > But that filesystem cannot know what the _other_ filesystem configurations > are. And that's what you'd have to have to mount.
At which point, userspace comes in. Who knows what userspace chooses. > > The obvious implementation has the userspace helper just mounting it, > > end of story. If the mount command fails, it fails. Much like autofs. > > Yes, that would work, but it's of questionable use. If you want autofs, > then just _use_ autofs. I don't mean to imply it's useful behaviour: only that it seems to happen by default if you don't do anything special to prevent it, if you see what I mean. It does seem useful to have _files_ mounted automagically (using loopback devices): for example, cd into a .iso file and it would be nice to see the contents. At this point, deciding on the preferred -EBUSY or not behaviour becomes relevant, as does deciding whether the .iso in this example is viewed using the kernel's isofs code, or using a userspace helper in the same way as we'd use one to browse a .zip file. -- Jamie
