Re: [RFC] New Driver Model for 2.5

Alan Cox
2001-10-25T23:50:03Z

> The cdrecord case is a high level issue, and scsi is a mess ;)

Grin

> We are not yet at a point where we can be more constructive
> than what was already said. Ultimately we need to move a bit
> forward with the real implementation and see how some problems
> show up. The architecture as it was designed so far is light,
> and most of the debate is not around it, it's around how it
> should be used by drivers & kernel subsystems ;)

I think I understand how to handle this and avoid races. Linus idea of
/proc files so you can ask "what is busy" solves most of it. Then the
policy daemon can make a choice about suspending or not.

If we make the proc file a large bitmask of events then the policy daemon
call to kernel becomes

"suspend even if [event-mask] set"

This means that a daemon call that races the start of say a CD burn will
fail and the daemon can rescan, rethink and if need be reissue the request
sanely.