From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Philippe Gerum <rpm@xenomai.org>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai-help] [Xenomai -help] User space access to DMA memory
Date: Wed, 12 Jan 2011 23:45:58 +0100 [thread overview]
Message-ID: <4D2E2F26.20000@domain.hid> (raw)
In-Reply-To: <4D2E28B0.8070202@domain.hid>
Gilles Chanteperdrix wrote:
>> if ((vaddr >= VMALLOC_START) && (vaddr < VMALLOC_END))
>>
>> returns false, and the memory is handled as if it were kmalloced memory.
>
> Replacing this test with if (!virt_addr_valid(vaddr)) should do the
> trick. Remains to see whethe this macro existed in older versions.
>
No, it will not work. vmalloc_to_page will fail for the same reason. So,
we can not use rtdm_mmap_to_user with virtual address returned by
dma_alloc_coherent, unless we start writing a page walk table like
vmalloc_to_page but which does not test that the give address is in the
vmalloc range.
--
Gilles.
next prev parent reply other threads:[~2011-01-12 22:45 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-20 16:52 [Xenomai-help] [Xenomai -help] User space access to DMA memory Herrera-Bendezu, Luis
2011-01-01 22:44 ` Gilles Chanteperdrix
2011-01-05 21:03 ` Herrera-Bendezu, Luis
2011-01-05 21:33 ` Gilles Chanteperdrix
2011-01-05 22:07 ` Steven A. Falco
2011-01-05 22:29 ` Gilles Chanteperdrix
2011-01-06 13:48 ` Herrera-Bendezu, Luis
2011-01-06 13:55 ` Gilles Chanteperdrix
2011-01-11 23:27 ` Gilles Chanteperdrix
2011-01-12 13:14 ` Herrera-Bendezu, Luis
2011-01-12 13:35 ` Gilles Chanteperdrix
2011-01-12 16:03 ` Herrera-Bendezu, Luis
2011-01-12 16:26 ` Gilles Chanteperdrix
2011-01-12 18:16 ` Herrera-Bendezu, Luis
2011-01-12 20:20 ` Gilles Chanteperdrix
2011-01-12 20:36 ` Gilles Chanteperdrix
2011-01-12 21:57 ` Herrera-Bendezu, Luis
2011-01-12 22:11 ` Philippe Gerum
2011-01-12 22:14 ` Gilles Chanteperdrix
2011-01-12 22:18 ` Gilles Chanteperdrix
2011-01-12 22:45 ` Gilles Chanteperdrix [this message]
2011-01-13 8:27 ` Philippe Gerum
2011-01-13 8:33 ` Gilles Chanteperdrix
2011-01-12 22:15 ` Gilles Chanteperdrix
2011-01-06 14:32 ` Steven A. Falco
2011-01-06 14:44 ` Gilles Chanteperdrix
2011-01-06 14:45 ` Steven A. Falco
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