From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: root@chaos.analogic.com
Cc: "Srinivas G." <srinivasg@esntechnologies.co.in>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Having problem with mmap system call!!!
Date: Thu, 16 Sep 2004 16:57:20 +0100 [thread overview]
Message-ID: <1095350240.22750.37.camel@localhost.localdomain> (raw)
In-Reply-To: <Pine.LNX.4.53.0409161050200.12305@chaos>
On Iau, 2004-09-16 at 15:54, Richard B. Johnson wrote:
> > SHM_FAIL is the wrong error check btw.
> >
>
> MAP_FAILED only appeared in real late 'C' runtime library headers.
> That's why the code defines SHM_FAIL, which is also correct, but
> doesn't cause a redefinition error.
SuS doesn't permit the use of SHM_FAIL. And you don't get redefinition
errors if you use ds
> Well that's really nice. Now, how do you do that? The kernel DS
> is not the user DS so you end up with a kernel hack instead of
> a user hack?
Who cares about DS ? the user space page tables get mapped, its how all
mmap functions work. A simple example is the sound drivers (2.4
drivers/sound) which kmalloc a buffer of kernel space then make it
mappable to the user
next prev parent reply other threads:[~2004-09-16 17:06 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <4EE0CBA31942E547B99B3D4BFAB348111078FE@mail.esn.co.in>
2004-09-16 14:07 ` Richard B. Johnson
2004-09-16 13:31 ` Alan Cox
2004-09-16 14:54 ` Richard B. Johnson
2004-09-16 15:57 ` Alan Cox [this message]
2004-09-16 18:13 ` Richard B. Johnson
2004-09-16 20:01 ` Alan Cox
2004-09-16 14:42 Srinivas G.
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1095350240.22750.37.camel@localhost.localdomain \
--to=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=root@chaos.analogic.com \
--cc=srinivasg@esntechnologies.co.in \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®