[PATCH 12/15] driver core: Implement tagged directory support for device classes.

[Eric W. Biederman]

Tejun Heo <htejun at gmail.com> writes:

> Greg, please disregard my earlier NACKs and commit the patches if you're
> okay with them.  I'm working on cleaning it up but I don't think I'll be
> able to make it in time for merge window and as Eric said getting the
> functionality in place is more important at this point as it doesn't
> affect user visible interface.
>
> Eric, with the multiple superblocks, sysfs now uses inode from the
> default sysfs_sb with dentries from other sb's.  Is this okay?  Are
> there any other filesystems which do this?

I don't know of any other filesystems where this unique challenge arises.
/proc almost qualifies but it never needs to be modified.

It is certainly ok to go from multiple dentries to a single inode.
I'm trying to remember why I choose to do that.  I think both because it simplifies
the locking and keeps us more efficient in the icache.

Eric