releases/4.6.5/drm-wrap-direct-calls-to-driver-gem_free_object-from-cma.patch

   1 From afe705be38f1e65b173868486944377186b9f206 Mon Sep 17 00:00:00 2001
   2 From: Chris Wilson <chris@chris-wilson.co.uk>
   3 Date: Tue, 31 May 2016 22:25:52 +0100
   4 Subject: drm: Wrap direct calls to driver->gem_free_object from CMA
   5
   6 From: Chris Wilson <chris@chris-wilson.co.uk>
   7
   8 commit afe705be38f1e65b173868486944377186b9f206 upstream.
   9
  10 Since the introduction of (struct_mutex) lockless GEM bo freeing, there
  11 are a pair of driver vfuncs for freeing the GEM bo, of which the driver
  12 may choose to only implement driver->gem_object_free_unlocked (and so
  13 avoid taking the struct_mutex along the free path). However, the CMA GEM
  14 helpers were still calling driver->gem_free_object directly, now NULL,
  15 and promptly dying on the fancy new lockless drivers. Oops.
  16
  17 Robert Foss bisected this to b82caafcf2303 (drm/vc4: Use lockless gem BO
  18 free callback) on his vc4 device, but that just serves as an enabler for
  19 9f0ba539d13ae (drm/gem: support BO freeing without dev->struct_mutex).
  20
  21 Reported-by: Robert Foss <robert.foss@collabora.com>
  22 Fixes: 9f0ba539d13ae (drm/gem: support BO freeing without dev->struct_mutex)
  23 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
  24 Cc: Robert Foss <robert.foss@collabora.com>
  25 Cc: Daniel Vetter <daniel.vetter@intel.com>
  26 Cc: Eric Anholt <eric@anholt.net>
  27 Cc: Alex Deucher <alexdeucher@gmail.com>
  28 Cc: Lucas Stach <l.stach@pengutronix.de>
  29 Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
  30 Tested-by: Robert Foss <robert.foss@collabora.com>
  31 Signed-off-by: Dave Airlie <airlied@redhat.com>
  32 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  33
  34 ---
  35  drivers/gpu/drm/drm_fb_cma_helper.c  |    2 +-
  36  drivers/gpu/drm/drm_gem_cma_helper.c |   12 +++---------
  37  2 files changed, 4 insertions(+), 10 deletions(-)
  38
  39 --- a/drivers/gpu/drm/drm_fb_cma_helper.c
  40 +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
  41 @@ -301,7 +301,7 @@ static int drm_fbdev_cma_create(struct d
  42  err_fb_info_destroy:
  43         drm_fb_helper_release_fbi(helper);
  44  err_gem_free_object:
  45 -       dev->driver->gem_free_object(&obj->base);
  46 +       drm_gem_object_unreference_unlocked(&obj->base);
  47         return ret;
  48  }
  49
  50 --- a/drivers/gpu/drm/drm_gem_cma_helper.c
  51 +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
  52 @@ -121,7 +121,7 @@ struct drm_gem_cma_object *drm_gem_cma_c
  53         return cma_obj;
  54
  55  error:
  56 -       drm->driver->gem_free_object(&cma_obj->base);
  57 +       drm_gem_object_unreference_unlocked(&cma_obj->base);
  58         return ERR_PTR(ret);
  59  }
  60  EXPORT_SYMBOL_GPL(drm_gem_cma_create);
  61 @@ -162,18 +162,12 @@ drm_gem_cma_create_with_handle(struct dr
  62          * and handle has the id what user can see.
  63          */
  64         ret = drm_gem_handle_create(file_priv, gem_obj, handle);
  65 -       if (ret)
  66 -               goto err_handle_create;
  67 -
  68         /* drop reference from allocate - handle holds it now. */
  69         drm_gem_object_unreference_unlocked(gem_obj);
  70 +       if (ret)
  71 +               return ERR_PTR(ret);
  72
  73         return cma_obj;
  74 -
  75 -err_handle_create:
  76 -       drm->driver->gem_free_object(gem_obj);
  77 -
  78 -       return ERR_PTR(ret);
  79  }
  80
  81  /**