[PATCH rfc 1/2] nvme: support smart read-only critical warning event

[Christoph Hellwig]

On Mon, Dec 04, 2017 at 11:24:34AM +0200, Sagi Grimberg wrote:
> In case a controller sent us a critical warning AER,
> we should query the smart information and in case the
> media was placed in read only mode, we need to set
> all the controller namespaces (and the namespaces heads)
> in read-only (or set to rw in case its not set).
> 
> Given that in fabrics we may also connect to a read-only
> subsystem, we add the disk as read-only to start with.
> Once the subsystem will be in rw mode, we restore
> the disk rw permissions.

We are sending the smart log notification on to userspace, so with this
we now have two parties that are trying to clear the log page..