In preparation for adding an atomic version of the disable code, extract
the actual disable operation into a separate function.
Signed-off-by: Brian Starkey <brian.star...@arm.com>
---
drivers/gpu/drm/drm_framebuffer.c | 87 +++++++++++++++++++++++--------------
1 file changed, 54 insertions(+), 33 deletions(-)
diff --git a/drivers/gpu/drm/drm_framebuffer.c
b/drivers/gpu/drm/drm_framebuffer.c
index 398efd6..528f75d 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -795,22 +795,61 @@ void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
EXPORT_SYMBOL(drm_framebuffer_cleanup);
/**
- * drm_framebuffer_remove - remove and unreference a framebuffer object
+ * __drm_framebuffer_remove - remove all usage of a framebuffer object
+ * @dev: drm device
* @fb: framebuffer to remove
*
* Scans all the CRTCs and planes in @dev's mode_config. If they're
- * using @fb, removes it, setting it to NULL. Then drops the reference to the
- * passed-in framebuffer. Might take the modeset locks.
+ * using @fb, removes it, setting it to NULL. Takes the modeset locks.
*
- * Note that this function optimizes the cleanup away if the caller holds the
- * last reference to the framebuffer. It is also guaranteed to not take the
- * modeset locks in this case.
+ * Returns:
+ * true if the framebuffer was successfully removed from use
*/
-void drm_framebuffer_remove(struct drm_framebuffer *fb)
+static bool __drm_framebuffer_remove(struct drm_device *dev, struct
drm_framebuffer *fb)
{
- struct drm_device *dev;
struct drm_crtc *crtc;
struct drm_plane *plane;
+ bool ret = true;
+
+ drm_modeset_lock_all(dev);
+ /* remove from any CRTC */
+ drm_for_each_crtc(crtc, dev) {
+ if (crtc->primary->fb == fb) {
+ /* should turn off the crtc */
+ if (drm_crtc_force_disable(crtc))
+ ret = false;
+ }
+ }
+
+ drm_for_each_plane(plane, dev) {
+ if (plane->fb == fb)
+ /* TODO: Propagate error here? */
+ drm_plane_force_disable(plane);
+ }
+ drm_modeset_unlock_all(dev);
+
+ return ret;
+}
+
+/**
+ * drm_framebuffer_remove - remove and unreference a framebuffer object
+ * @fb: framebuffer to remove
+ *
+ * drm ABI mandates that we remove any deleted framebuffers from active usage.
+ * This function takes care of this detail, disabling any CRTCs/Planes which
+ * are using the framebuffer being removed.
+ *
+ * Since most sane clients only remove framebuffers they no longer need, we
+ * skip the disable step if the caller holds the last reference to the
+ * framebuffer. It is also guaranteed to not take the modeset locks in
+ * this case.
+ *
+ * Before returning this function drops (what should be) the last reference
+ * on the framebuffer.
+ */
+void drm_framebuffer_remove(struct drm_framebuffer *fb)
+{
+ struct drm_device *dev;
if (!fb)
return;
@@ -820,37 +859,19 @@ void drm_framebuffer_remove(struct drm_framebuffer *fb)
WARN_ON(!list_empty(&fb->filp_head));
/*
- * drm ABI mandates that we remove any deleted framebuffers from active
- * useage. But since most sane clients only remove framebuffers they no
- * longer need, try to optimize this away.
- *
* Since we're holding a reference ourselves, observing a refcount of 1
- * means that we're the last holder and can skip it. Also, the refcount
- * can never increase from 1 again, so we don't need any barriers or
- * locks.
+ * means that we're the last holder and can skip the disable. Also, the
+ * refcount can never increase from 1 again, so we don't need any
+ * barriers or locks.
*
- * Note that userspace could try to race with use and instate a new
+ * Note that userspace could try to race with us and instate a new
* usage _after_ we've cleared all current ones. End result will be an
* in-use fb with fb-id == 0. Userspace is allowed to shoot its own foot
* in this manner.
*/
- if (drm_framebuffer_read_refcount(fb) > 1) {
- drm_modeset_lock_all(dev);
- /* remove from any CRTC */
- drm_for_each_crtc(crtc, dev) {
- if (crtc->primary->fb == fb) {
- /* should turn off the crtc */
- if (drm_crtc_force_disable(crtc))
- DRM_ERROR("failed to reset crtc %p when
fb was deleted\n", crtc);
- }
- }
-
- drm_for_each_plane(plane, dev) {
- if (plane->fb == fb)
- drm_plane_force_disable(plane);
- }
- drm_modeset_unlock_all(dev);
- }
+ if (drm_framebuffer_read_refcount(fb) > 1)
+ if (!__drm_framebuffer_remove(dev, fb))
+ DRM_ERROR("failed to remove fb from active usage\n");
drm_framebuffer_unreference(fb);
}
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
