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From: Filippo Sironi <filippo.sironi@gmail.com>
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Date: Sat, 3 Dec 2011 10:19:43 +0100
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Cc: Sironi Filippo <filippo.sironi@gmail.com>,
	Poul-Henning Kamp <phk@phk.freebsd.dk>
Subject: Re: mmap implementation for cdev
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Ok, that's what I was suspecting.
Do you have any ideas on how to get the behavior I described in the =
previous mail?

On 03/dic/2011, at 10.16, Poul-Henning Kamp wrote:

> In message <A51F9B30-A71A-49A5-B684-16EC3C127BC9@gmail.com>, Filippo =
Sironi wri
> tes:
>=20
>> The problem is that when I come =3D
>> back to user space all the threads write in memory page mapped by the =
=3D
>> first thread that called the mmap leaving their memory pages =
untouched.
>=20
> That's how cdev->mmap works, it is global rather than per-thread.
>=20
>=20
> --=20
> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> phk@FreeBSD.ORG         | TCP/IP since RFC 956
> FreeBSD committer       | BSD since 4.3-tahoe   =20
> Never attribute to malice what can adequately be explained by =
incompetence.