[PATCH] iommu: omap_iovmm: support non page-aligned buffers in iommu_vmap

Laurent Pinchart laurent.pinchart at ideasonboard.com
Thu Sep 1 09:31:13 EDT 2011


Hi Ohad,

On Thursday 01 September 2011 13:47:26 Ohad Ben-Cohen wrote:
> On Wed, Aug 31, 2011 at 1:52 PM, Ohad Ben-Cohen <ohad at wizery.com> wrote:
> > From: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > 
> > omap_iovmm requires page-aligned buffers, and that sometimes causes
> > omap3isp failures (i.e. whenever the buffer passed from userspace is not
> > page-aligned).
> > 
> > Remove this limitation by rounding the address of the first page entry
> > down, and adding the offset back to the device address.
> 
> Seems like the unmap paths were skipped (need to adjust the sizes in
> the unmap path too).
> 
> Laurent, if it looks good to you, I'll just squash it to the original
> patch and repost:

Do you have a tree where the current code base can be found ?

> diff --git a/drivers/iommu/omap-iovmm.c b/drivers/iommu/omap-iovmm.c
> index d28a256..39bdb92 100644
> --- a/drivers/iommu/omap-iovmm.c
> +++ b/drivers/iommu/omap-iovmm.c
> @@ -447,7 +447,7 @@ err_out:
>         for_each_sg(sgt->sgl, sg, i, j) {
>                 size_t bytes;
> 
> -               bytes = sg->length;
> +               bytes = sg->length + sg->offset;
>                 order = get_order(bytes);
> 
>                 /* ignore failures.. we're already handling one */
> @@ -476,7 +476,7 @@ static void unmap_iovm_area(struct iommu_domain
> *domain, str size_t bytes;
>                 int order;
> 
> -               bytes = sg->length;
> +               bytes = sg->length + sg->offset;
>                 order = get_order(bytes);
> 
>                 err = iommu_unmap(domain, start, order);

-- 
Regards,

Laurent Pinchart



More information about the linux-arm-kernel mailing list