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To: Manuel =?iso-8859-1?Q?St=FChn?= <freebsdnewbie@freenet.de>
cc: freebsd-hackers@freebsd.org
Subject: Re: mmap device-drivers
In-reply-to: <20170314090905.GA94880@freebsd-t420.fritz.box>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <20170314090905.GA94880@freebsd-t420.fritz.box>
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Date: Tue, 14 Mar 2017 09:17:48 +0000
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--------
In message <20170314090905.GA94880@freebsd-t420.fritz.box>, Manuel =3D?iso=
-8859-1
?Q?St=3DFChn?=3D writes:

>is it possible for a device driver to keep track if there are still
>active mmap() pointers pointing to that device?

I looked at this back in PCMCIA days and it was not possible, and my
attempts to implement it did not succeed.

-- =

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    =

Never attribute to malice what can adequately be explained by incompetence=
.