| Message ID | 20181105101211.22737-1-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/lease: look at ->universal_planes only once | expand |
On Mon, Nov 05, 2018 at 11:12:11AM +0100, Daniel Vetter wrote: > It's lockless, and userspace might chance it underneath us. That's not > really a problem, all userspace gets is a slightly dysfunctional > lease with the current code. But this might change, and gcc might > decide to reload a few too many times, and then boom. So better safe > than sorry. > > v2: Remove the now unused lessor_priv argument from validate_lease() > (Keith). > > v3: Actually add everything ... silly me. > > Cc: Keith Packard <keithp@keithp.com> > Cc: Dave Airlie <airlied@gmail.com> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> All pulled in with CI approving and Keith's irc-ack on this one here. -Daniel > --- > drivers/gpu/drm/drm_lease.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c > index 3b0342a45ae9..3650d3c46718 100644 > --- a/drivers/gpu/drm/drm_lease.c > +++ b/drivers/gpu/drm/drm_lease.c > @@ -353,9 +353,9 @@ void drm_lease_revoke(struct drm_master *top) > } > > static int validate_lease(struct drm_device *dev, > - struct drm_file *lessor_priv, > int object_count, > - struct drm_mode_object **objects) > + struct drm_mode_object **objects, > + bool universal_planes) > { > int o; > int has_crtc = -1; > @@ -372,14 +372,14 @@ static int validate_lease(struct drm_device *dev, > if (objects[o]->type == DRM_MODE_OBJECT_CONNECTOR && has_connector == -1) > has_connector = o; > > - if (lessor_priv->universal_planes) { > + if (universal_planes) { > if (objects[o]->type == DRM_MODE_OBJECT_PLANE && has_plane == -1) > has_plane = o; > } > } > if (has_crtc == -1 || has_connector == -1) > return -EINVAL; > - if (lessor_priv->universal_planes && has_plane == -1) > + if (universal_planes && has_plane == -1) > return -EINVAL; > return 0; > } > @@ -393,6 +393,8 @@ static int fill_object_idr(struct drm_device *dev, > struct drm_mode_object **objects; > u32 o; > int ret; > + bool universal_planes = READ_ONCE(lessor_priv->universal_planes); > + > objects = kcalloc(object_count, sizeof(struct drm_mode_object *), > GFP_KERNEL); > if (!objects) > @@ -421,7 +423,7 @@ static int fill_object_idr(struct drm_device *dev, > } > } > > - ret = validate_lease(dev, lessor_priv, object_count, objects); > + ret = validate_lease(dev, object_count, objects, universal_planes); > if (ret) { > DRM_DEBUG_LEASE("lease validation failed\n"); > goto out_free_objects; > @@ -448,7 +450,7 @@ static int fill_object_idr(struct drm_device *dev, > object_id, ret); > goto out_free_objects; > } > - if (obj->type == DRM_MODE_OBJECT_CRTC && !lessor_priv->universal_planes) { > + if (obj->type == DRM_MODE_OBJECT_CRTC && !universal_planes) { > struct drm_crtc *crtc = obj_to_crtc(obj); > ret = idr_alloc(leases, &drm_lease_idr_object, crtc->primary->base.id, crtc->primary->base.id + 1, GFP_KERNEL); > if (ret < 0) { > -- > 2.14.4 >
diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c index 3b0342a45ae9..3650d3c46718 100644 --- a/drivers/gpu/drm/drm_lease.c +++ b/drivers/gpu/drm/drm_lease.c @@ -353,9 +353,9 @@ void drm_lease_revoke(struct drm_master *top) } static int validate_lease(struct drm_device *dev, - struct drm_file *lessor_priv, int object_count, - struct drm_mode_object **objects) + struct drm_mode_object **objects, + bool universal_planes) { int o; int has_crtc = -1; @@ -372,14 +372,14 @@ static int validate_lease(struct drm_device *dev, if (objects[o]->type == DRM_MODE_OBJECT_CONNECTOR && has_connector == -1) has_connector = o; - if (lessor_priv->universal_planes) { + if (universal_planes) { if (objects[o]->type == DRM_MODE_OBJECT_PLANE && has_plane == -1) has_plane = o; } } if (has_crtc == -1 || has_connector == -1) return -EINVAL; - if (lessor_priv->universal_planes && has_plane == -1) + if (universal_planes && has_plane == -1) return -EINVAL; return 0; } @@ -393,6 +393,8 @@ static int fill_object_idr(struct drm_device *dev, struct drm_mode_object **objects; u32 o; int ret; + bool universal_planes = READ_ONCE(lessor_priv->universal_planes); + objects = kcalloc(object_count, sizeof(struct drm_mode_object *), GFP_KERNEL); if (!objects) @@ -421,7 +423,7 @@ static int fill_object_idr(struct drm_device *dev, } } - ret = validate_lease(dev, lessor_priv, object_count, objects); + ret = validate_lease(dev, object_count, objects, universal_planes); if (ret) { DRM_DEBUG_LEASE("lease validation failed\n"); goto out_free_objects; @@ -448,7 +450,7 @@ static int fill_object_idr(struct drm_device *dev, object_id, ret); goto out_free_objects; } - if (obj->type == DRM_MODE_OBJECT_CRTC && !lessor_priv->universal_planes) { + if (obj->type == DRM_MODE_OBJECT_CRTC && !universal_planes) { struct drm_crtc *crtc = obj_to_crtc(obj); ret = idr_alloc(leases, &drm_lease_idr_object, crtc->primary->base.id, crtc->primary->base.id + 1, GFP_KERNEL); if (ret < 0) {
It's lockless, and userspace might chance it underneath us. That's not really a problem, all userspace gets is a slightly dysfunctional lease with the current code. But this might change, and gcc might decide to reload a few too many times, and then boom. So better safe than sorry. v2: Remove the now unused lessor_priv argument from validate_lease() (Keith). v3: Actually add everything ... silly me. Cc: Keith Packard <keithp@keithp.com> Cc: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> --- drivers/gpu/drm/drm_lease.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)