Date: Thu, 27 Feb 2003 11:03:58 -0800 From: Alfred Perlstein <bright@mu.org> To: phk@phk.freebsd.dk Cc: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern kern_conf.c src/sys/sys conf.h Message-ID: <20030227190358.GE7206@elvis.mu.org> In-Reply-To: <9124.1046372176@critter.freebsd.dk> References: <20030227184358.GC7206@elvis.mu.org> <9124.1046372176@critter.freebsd.dk>
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* phk@phk.freebsd.dk <phk@phk.freebsd.dk> [030227 10:56] wrote: > In message <20030227184358.GC7206@elvis.mu.org>, Alfred Perlstein writes: > > > >Perhaps if you remebered the name assigned and it came back again you > >could assign the old major? > > The simple and effective solution is to refcount cdevsw structures > from make_dev(+) and destroy_dev(-) calls and when the count goes > to zero reclaim the major number. I experiment with this already > here, but it has some locking implications which forces me to > reconsider the self-locking structure of kern_conf.c and devfs and > that makes the otherwise rather simple task non-simple. I'll get > there eventually though. Oh, I didn't realize that this wasn't already implemented. > The other issue which I am pondering is a way to share major# for > devices which don't care about which exact minor# they get. Typical > examples being /dev/ccd.ctl and /dev/geom.ctl, wasting an entire > major number for each of those is silly. > > I may introduce a different magic marker which says "allocate me > both a major and minor" which would allow these kinds of devices > to share one major number. That's a good idea, a "don't care" node, even if hardwired would work. -- -Alfred Perlstein [alfred@freebsd.org] 'Instead of asking why a piece of software is using "1970s technology," start asking why software is ignoring 30 years of accumulated wisdom.' To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message
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