Re: [PATCH 30/38] vfs: syscall: Add fsmount() to create a mount for a superblock [ver #10]

David Howells
2018-07-27T22:06:24Z

Andy Lutomirski <luto@amacapital.net> wrote:

> I have a potentially silly objection. For the old timers, "mount" means to
> stick a reel of tape or some similar object onto a reader, which seems to
> imply that "mount" means to start up the filesystem. For younguns, this
> meaning is probably lost, and the more obvious meaning is to "mount" it into
> some location in the VFS hierarchy a la vfsmount. The patch description
> doesn't disambiguate it, and obviously people used to mount(2)/mount(8) are
> just likely to be confused.

The problem is that inside the kernel it *is* a "mount".

How about I change the first paragraph to:

Provide a system call by which a filesystem opened with fsopen() and
configured by a series of fsconfig() calls can have a detached mount
object created for it. This mount object can then be attached to the
VFS mount hierarchy using move_mount() by passing the returned file
descriptor as the from directory fd.

> At the very least, your description should make it absolutely clear what you
> mean. Even better IMO would be to drop the use of the word "mount" entirely

I'm not sure that's a reasonable idea, given the "mounting" is how this is
done.

Can you suggest a word that encapsulates what it is that fsmount() returns?
It's almost, but not quite identical with what open(O_PATH) returns, since it
has to be torn down if not actually mounted somewhere when the fd is closed.

> and maybe rename the syscall.
>
> From a very brief reading, I think you are giving it the meaning that would
> be implied by fsstart(2).

Do you have a reference for the manpage for that? Google doesn't seem to find
it.

David