Some FC adapters from Marvell offer the ability to encrypt data in flight
(EDIF). This feature requires an application to act as an authenticator.

During runtime, driver and authentication application need to stay in sync
in terms of: Session being down|up, arrival of new authentication
message (AUTH ELS) and SADB update completion.

These events are queued up as doorbell to the authentication
application. Application would read this doorbell on regular basis to stay
up to date. Each SCSI host would have a separate doorbell queue.

The doorbell interface can daisy chain a list of events for each read. Each
event contains an event code + hint to help application steer the next
course of action.

Link: https://lore.kernel.org/r/20210624052606.21613-9-njavali@marvell.comReviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Co-developed-by: Larry Wisneski <Larry.Wisneski@marvell.com>
Signed-off-by: Larry Wisneski <Larry.Wisneski@marvell.com>
Co-developed-by: Duane Grigsby <duane.grigsby@marvell.com>
Signed-off-by: Duane Grigsby <duane.grigsby@marvell.com>
Co-developed-by: Rick Hicksted Jr <rhicksted@marvell.com>
Signed-off-by: Rick Hicksted Jr <rhicksted@marvell.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>