On Thursday 06 May 2010 06:06:21, Mauro Carvalho Chehab wrote:
> Hi Arnout,
>
> Arnout Vandecappelle wrote:
> > videobuf_dma_init_user_locked() uses get_user_pages() to get the
> > virtual-to-physical address mapping for user-allocated memory.
> > However, the user-
On Wednesday 24 March 2010 06:43:22, Sakari Ailus wrote:
> Hi Arnout,
>
> Thanks for the patch.
>
> Arnout Vandecappelle wrote:
[snip]
> > - dma_sync_sg_for_cpu(q->dev, dma->sglist, dma->nr_pages,
> > dma->direction);
> > + dma_sync_sg
videobuf_dma_init_user_locked() uses get_user_pages() to get the
virtual-to-physical address mapping for user-allocated memory.
However, the user-allocated memory may be non-pageable because it
is an I/O range or similar. get_user_pages() fails with -EFAULT
in that case.
If the user-allocated mem
videobuf_pages_to_sg() and videobuf_vmalloc_to_sg() happen to create
a scatterlist element for every page. However, this is not true for
bus addresses, so other functions shouldn't rely on the length of the
scatter list being equal to nr_pages.
---
drivers/media/video/videobuf-dma-sg.c |4 ++-
Hoi,
[Please CC me, I'm not subscribed.]
I'm implementing zerocopy transfer from a v4l2 camera to the DSP on an
OMAP3 (based on earlier work by Stefan Kost [1][2]). Therefore I'm using
V4L2_MEMORY_USERPTR to pass in the memory area allocated by TI's DMAI
driver. However, this has flags VM
On Wednesday 17 March 2010 21:57:18, Sakari Ailus wrote:
> Arnout Vandecappelle wrote:
> > diff --git a/drivers/media/video/videobuf-dma-sg.c
> > b/drivers/media/video/videobuf-dma-sg.c index da1790e..3b6f1b8 100644
> > --- a/drivers/media/video/videobuf-dma-sg.c
> >
videobuf_dma_init_user_locked() uses get_user_pages() to get the
virtual-to-physical address mapping for user-allocated memory.
However, the user-allocated memory may be non-pageable because it
is an I/O range or similar. get_user_pages() fails with -EFAULT
in that case.
If the user-allocated mem
videobuf_pages_to_sg() and videobuf_vmalloc_to_sg() happen to create
a scatterlist element for every page. However, this is not true for
bus addresses, so other functions shouldn't rely on the length of the
scatter list being equal to nr_pages.
---
drivers/media/video/videobuf-dma-sg.c |6 +++
Here is an updated patch, properly split up and with commit messages.
I've tested it on my OMAP3 board an it works. I don't have anything else
to test it with.
Regards,
Arnout
[PATCH 1/2] V4L/DVB: buf-dma-sg.c: don't assume nr_pages == sglen
[PATCH 2/2] V4L/DVB: buf-dma-sg.c: support non-
Here's a first attempt at allowing IO memory for USERPTR buffers.
It also fixes another issue: it was assumed that
dma->sglen == dma->nr_pages. I'll split that up in a separate patch in the
final version.
Regards,
Arnout
On Wednesday 03 March 2010 15:12:44, Arnout Van
only get pages from areas that don't have
these flags set.
If I get positive feedback on this, I'll supply a patch.
[1] https://bugzilla.gnome.org/show_bug.cgi?id=583890
[2] http://thread.gmane.org/gmane.linux.drivers.video-input-
infrastructure/6209
--
Arnout Vandecappelle
11 matches
Mail list logo