[PATCH 1/1] drm/ttm: fix offset in VMAs with a pg_offs in ttm_bo_vm_access

[Christian König]

Am 28.07.20 um 20:27 schrieb Felix Kuehling:
> VMAs with a pg_offs that's offset from the start of the vma_node need
> to adjust the offset within the BO accordingly. This matches the
> offset calculation in ttm_bo_vm_fault_reserved.
>
> Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
> Tested-by: Laurent Morichetti <laurent.morichetti at amd.com>

Reviewed-by: Christian König <christian.koenig at amd.com>

Going to pick that up for inclusion in drm-misc-next.

> ---
>   drivers/gpu/drm/ttm/ttm_bo_vm.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
> index 389128b8c4dd..60b41447bec8 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
> @@ -405,8 +405,10 @@ static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo,
>   int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
>   		     void *buf, int len, int write)
>   {
> -	unsigned long offset = (addr) - vma->vm_start;
>   	struct ttm_buffer_object *bo = vma->vm_private_data;
> +	unsigned long offset = (addr) - vma->vm_start +
> +		((vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node))
> +		 << PAGE_SHIFT);
>   	int ret;
>   
>   	if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->num_pages)