System Quiesce Entry Point

A driver that manages devices must implement the quiesce(9E) entry point. Drivers that do not manage devices can set the devo_quiesce field in the dev_ops structure to ddi_quiesce_not_needed(). The quiesce() function can be called only when the system is single-threaded at high PIL (priority interrupt level) with preemption disabled. Therefore, this function must not be blocked. If a device has a defined reset state configuration, the driver should return that device to that reset state as part of the quiesce operation. An example of this case is Fast Reboot, where firmware is bypassed when booting to a new operating system image.