在 2018/1/26 21:16, Thierry Escande 写道:

From: Ørjan Eide orjan.eide@arm.com

When mapping external DMA-bufs through the PRIME mmap call, we might be given an offset which has to be respected. However for the internal DRM GEM mmap path, we have to ignore the fake mmap offset used to identify the buffer only. Currently the code always zeroes out vma->vm_pgoff, which breaks the former.

This patch fixes the problem by moving the vm_pgoff assignment to a function that is used only for GEM mmap path, so that the PRIME path retains the original offset.

Cc: Daniel Kurtz djkurtz@chromium.org Signed-off-by: Ørjan Eide orjan.eide@arm.com Signed-off-by: Tomasz Figa tfiga@chromium.org Signed-off-by: Sean Paul seanpaul@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com Tested-by: Heiko Stuebner heiko@sntech.de

---

drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index 5d52020deca1..074db7a92809 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -264,7 +264,6 @@ static int rockchip_drm_gem_object_mmap(struct drm_gem_object *obj, * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap(). */ vma->vm_flags &= ~VM_PFNMAP;

• vma->vm_pgoff = 0;

  if (rk_obj->pages) ret = rockchip_drm_gem_object_mmap_iommu(obj, vma);

@@ -299,6 +298,12 @@ int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) if (ret) return ret;

• /*

• * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
  

• * whole buffer from the start.
  

• */
  

• vma->vm_pgoff = 0;

• obj = vma->vm_private_data;

  return rockchip_drm_gem_object_mmap(obj, vma);

Reviewed-by: Sandy huang hjc@rock-chips.com