[PATCH] nvme: block ioctls if controller not in a live state

[James Smart]

On 5/8/2018 10:11 PM, Christoph Hellwig wrote:
> On Mon, May 07, 2018 at 03:55:58PM -0700, James Smart wrote:
>> Rather than allow ioctl-based admin cmds to get intermixed on the admin
>> queue with commands being used to initialize a controller or io commands
>> to go to a controller in reconnect thus possibly hanging, reject them
>> if the controller isn't in the LIVE state. Reject with an -EAGAIN status
>> so that the app knows it could retry.
> -EAGAIN implies that you can poll for the fd to be ready, so I think
> this is the wrong error code here.

That is the exact intent.  I do want the app to trigger off -EAGAIN in 
those two states and try again after a delay./  Perhaps I should change 
from !LIVE to NEW || RESETTING || CONNECTING to be more explicit.  I 
assumed !LIVE was sufficient as the other states should transition to 
LIVE or the delete path is taken which would remove the fd all together.

-- james