linuxkpi: Add orderly_poweroff

[manu]

Summary

This simply poweroff the system.
Needed by drm-kmod v5.8

MFC after: 2 weeks
Sponsored by: Beckhoff Automation GmbH & Co. KG

[bz]

sys/compat/linuxkpi/common/include/linux/reboot.h

27

I thought things got harmonized onto one "_".

40

Do you actually need anything but RB_POWEROFF for these two as shutdown_nice_task_fn will not look at the others if that is set. And if you run into kern_reboot RB_NOSYNC gets set (but unlikely you'd run into that from here given that requires no init running).

[manu]

Remove RB_HALT (not needed).
Remove one _ in header guard.

[manu]

sys/compat/linuxkpi/common/include/linux/reboot.h

40

RB_NOSYNC is needed in that case so we don't call bufshutdown

[bz]

sys/compat/linuxkpi/common/include/linux/reboot.h

40

RB_NOSYNC is needed in that case so we don't call bufshutdown

{{{

340 /*
341  * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
342  */
343 void
344 shutdown_nice(int howto)
345 {
346
347         if (initproc != NULL && !SCHEDULER_STOPPED()) {
348                 shutdown_nice_task.ta_context = (void *)(uintptr_t)howto;
349                 taskqueue_enqueue(taskqueue_fast, &shutdown_nice_task);
350         } else {
351                 /*
352                  * No init(8) running, or scheduler would not allow it
353                  * to run, so simply reboot.
354                  */
355                 kern_reboot(howto | RB_NOSYNC);
356         }
357 }

}}}

The first runs shutdown_nice_task_fn which then calls kern_psignal() depending on howto but doesn't pass it on.
The latter does add RB_NOSYNC itself.

[manu]

sys/compat/linuxkpi/common/include/linux/reboot.h

40

Ah yes indeed, I've missed that howto isn't passed on.
Will update and make this a single call to shutdown_nice then.

[manu]

Remove RB_NOSYNC as it's not passed on.