On Tue, Sep 03, 2019 at 10:46:20AM -0600, Keith Busch wrote: > Could we possibly make /dev/nvmeX be a subsystem handle without causing > trouble for anyone? This would essentially be the same thing as today > for non-CMIC controllers with a device-per-controller and only affects > the CMIC ones.
A per-subsyste character device doesn't make sense, as a lot of admin command require a specific controller. If this really is an isue for people we'll just need to refcount the handle allocation. That is: - nvme_init_ctrl allocates a new nvme_instance or so object, which does the ida_simple_get. - we allocate a new subsystem that reuses the handle and grabs a reference in nvme_init_subsystem, then if we find an existing subsystem we drop that reference again. - last free of a ctrl or subsystem also drops a reference, with the final free releasing the ida
