[PATCH] drm/ttm: Don't clear page metadata of imported sg pages

[Jakob Bornecrantz]

----- Ursprungligt meddelande -----
> These page pointers shouldn't be visible to TTM in the first place, but
> until we fix that up, don't clear the page metadata because that
> will upset the exporter.
> 
> Reported-by: Cristoph Haag <haagch.christoph at googleemail.com>
> Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
> ---
>  drivers/gpu/drm/ttm/ttm_tt.c |    3 +++
>  1 file changed, 3 insertions(+)

Reviewed-by: Jakob Bornecrantz <jakob at vmware.com>

> 
> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
> index 9af9908..75f3190 100644
> --- a/drivers/gpu/drm/ttm/ttm_tt.c
> +++ b/drivers/gpu/drm/ttm/ttm_tt.c
> @@ -380,6 +380,9 @@ static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
>  	pgoff_t i;
>  	struct page **page = ttm->pages;
>  
> +	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
> +		return;
> +
>  	for (i = 0; i < ttm->num_pages; ++i) {
>  		(*page)->mapping = NULL;
>  		(*page++)->index = 0;
> --
> 1.7.10.4
>