orangefs: use struct mutex

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs: simply devreq module refcounting

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs: don't assign s_type

The VFS already takes care of this.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs: remove FS_REQUIRES_DEV

These days we don't need FS_REQUIRES_DEV as long as fsid/uuid is provided.
And we better provide one for orangefs, as the anon dev_t used by it isn't
stable over reboots.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs: remove useless call to shrink_dcache_sb in devreq_release

This call shrinks the dcache on the filesystem that the devreq node sits on
(typically tmpfs these days), and thus has no real use for orangefs.  Remove
it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>