linux-kernel - Re: [PATCH 2/2] [media] videobuf-dma-contig: use vm_iomap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20130417095657.1ab81623@redhat.com>
Date:	Wed, 17 Apr 2013 09:56:57 -0300
From:	Mauro Carvalho Chehab <mchehab@...hat.com>
To:	Mauro Carvalho Chehab <mchehab@...hat.com>
Cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Clemens Ladisch <clemens@...isch.de>,
	Arnd Bergmann <arnd@...db.de>, Takashi Iwai <tiwai@...e.de>,
	Linux Media Mailing List <linux-media@...r.kernel.org>
Subject: Re: [PATCH 2/2] [media] videobuf-dma-contig: use vm_iomap_memory()

Em Wed, 17 Apr 2013 09:22:16 -0300
Mauro Carvalho Chehab <mchehab@...hat.com> escreveu:

> vm_iomap_memory() provides a better end user interface than
> remap_pfn_range(), as it does the needed tests before doing
> mmap.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab@...hat.com>
> ---
>  drivers/media/v4l2-core/videobuf-dma-contig.c | 7 +------
>  1 file changed, 1 insertion(+), 6 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/videobuf-dma-contig.c b/drivers/media/v4l2-core/videobuf-dma-contig.c
> index 67f572c..7e6b209 100644
> --- a/drivers/media/v4l2-core/videobuf-dma-contig.c
> +++ b/drivers/media/v4l2-core/videobuf-dma-contig.c
> @@ -303,14 +303,9 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
>  		goto error;
>  
>  	/* Try to remap memory */
> -
>  	size = vma->vm_end - vma->vm_start;
> -	size = (size < mem->size) ? size : mem->size;
> -
>  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> -	retval = remap_pfn_range(vma, vma->vm_start,
> -				 mem->dma_handle >> PAGE_SHIFT,
> -				 size, vma->vm_page_prot);
> +	retval = vm_iomap_memory(vma, vma->vm_start, size);

Just to be sure, that changing from remap_pfn_range() to io_remap_pfn_range()
won't cause any side-effects, I double-checked that, for all drivers using
this code, that remap_pfn_range is equal to io_remap_pfn_range.

The Timberdale driver was a little trickier to check, as VIDEO_TIMBERDALE
doesn't depend on any architecture. However, this driver was submitted and
was known to work only on the Intel in-Vehicle Infotainment reference board
russelville. According with http://wiki.meego.com/In-vehicle, the
architecture for it is x86 (Intel Atom Z5xx).

In summary, those are the archs where this core driver is used, with the
corresponding drivers that make such usage:

powerpc:
	drivers/media/platform/fsl-viu.c

arm:
	drivers/media/platform/omap/omap_vout.c
	drivers/media/platform/omap/omap_vout_vrfb.c
	drivers/media/platform/soc_camera/mx1_camera.c
	drivers/media/platform/soc_camera/omap1_camera.c

sh:
	drivers/media/platform/sh_vou.c

x86:
	drivers/media/platform/timblogiw.c

-- 

Cheers,
Mauro
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/