From: Clemens Kolbitsch <clemens.kol@gmx.at>
To: "Chris Smith" <smitty1elkml@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: Re: Copy large memory regions from & to userspace
Date: Fri, 31 Aug 2007 15:45:28 +0200 [thread overview]
Message-ID: <200708311545.29154.clemens.kol@gmx.at> (raw)
In-Reply-To: <9b53a56d0708310625q14defcb1l98ab8ce1df2c8fd7@mail.gmail.com>
On Friday 31 August 2007 15:25:40 you wrote:
> On 8/30/07, Clemens Kolbitsch <clemens.kol@gmx.at> wrote:
> > Hi!
> > Just a short question: What is the correct method of copying large areas
> > of memory from userspace into userspace when running in kernel-mode?
>
> relayfs?
no... I'm copying user-memory to user-memory, not kernel-to-user, however
running the code in kernel-mode.
what i wanted to know is how to check the access-rights...
i didn't get any other answers, so for now i'm just using
if (access_ok(VERIFY_READ, from, PAGE_SIZE) &&
access_ok(VERIFY_WRITE, to, PAGE_SIZE))
{
memcpy(to, from, PAGE_SIZE);
}
and hope that this is the *correct* way to do it...
next prev parent reply other threads:[~2007-08-31 13:45 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-08-30 22:29 Clemens Kolbitsch
[not found] ` <9b53a56d0708310625q14defcb1l98ab8ce1df2c8fd7@mail.gmail.com>
2007-08-31 13:45 ` Clemens Kolbitsch [this message]
[not found] <fa.0TqRgC3Smn96vb+Bwv5QRWKBTQg@ifi.uio.no>
[not found] ` <fa.x2L04usZZxVIMYSdrufu+Hen9aY@ifi.uio.no>
[not found] ` <fa.tMlh7ZYvNMxPEL69Eww8ErwDEmw@ifi.uio.no>
2007-09-01 1:48 ` Robert Hancock
2007-09-01 6:10 ` Jan Engelhardt
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