From: Yong Zhang <yong.zhang@windriver.com>
To: Tom Brown <sa212+emis@cyconix.com>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: Re: Question: how to copy to user space from a tasklet
Date: Fri, 15 Oct 2010 10:15:46 +0800 [thread overview]
Message-ID: <20101015021546.GA15339@windriver.com> (raw)
In-Reply-To: <4CB6DEC4.4040408@cyconix.com>
On Thu, Oct 14, 2010 at 11:43:16AM +0100, Tom Brown wrote:
> [Sorry to have to ask this here - I can't find any driver-specific
> newsgroup or mailing lists - are there any??]
>
> I have a driver which needs to copy device data direct to user space
> from a tasklet. I need to do this because the device is continuously
> DMA'ing into user space, with no user intervention, so the user
> isn't waiting for data. In other words, I don't have any
> user-associated process to wake up.
>
> This means that I have to somehow copy the data directly to the user
> from the tasklet, without sleeping, and without direct access to
> user context. Can someone tell me how to do this?
Are you seeking for probe_kernel_read/write(include/linux/uaccess.h)?
Thanks,
Yong
>
> Thanks
>
> Tom
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next prev parent reply other threads:[~2010-10-15 2:15 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-14 10:43 Question: how to copy to user space from a tasklet Tom Brown
2010-10-15 2:15 ` Yong Zhang [this message]
2010-10-15 5:57 ` Stefan Richter
2010-10-15 8:59 ` Arnd Bergmann
2010-10-18 15:45 ` Tom Brown
2010-10-18 17:01 ` Stefan Richter
2010-10-18 18:02 ` Tom Brown
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