drm: Clean up pending events in the core
There's really no reason to not do so, instead of replicating this
for every use-case and every driver. Now we can't just nuke the events,
since that would still mean that all drm_event users would need to know
when that has happened, since calling e.g. drm_send_event isn't allowed
any more. Instead just unlink them from the file, and detect this case
and handle it appropriately in all functions.
v2: Adjust existing kerneldoc too.
v3: Improve wording of the kerneldoc and split out vblank cleanup (Laurent).
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-2-git-send-email-daniel.vetter@ffwll.ch
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index eb6a02f..afe8c53 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -264,6 +264,7 @@
INIT_LIST_HEAD(&priv->fbs);
mutex_init(&priv->fbs_lock);
INIT_LIST_HEAD(&priv->blobs);
+ INIT_LIST_HEAD(&priv->pending_event_list);
INIT_LIST_HEAD(&priv->event_list);
init_waitqueue_head(&priv->event_wait);
priv->event_space = 4096; /* set aside 4k for event buffer */
@@ -366,6 +367,13 @@
v->base.destroy(&v->base);
}
+ /* Unlink pending events */
+ list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
+ pending_link) {
+ list_del(&e->pending_link);
+ e->file_priv = NULL;
+ }
+
/* Remove unconsumed events */
list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
list_del(&e->link);
@@ -712,6 +720,7 @@
file_priv->event_space -= e->length;
p->event = e;
+ list_add(&p->pending_link, &file_priv->pending_event_list);
p->file_priv = file_priv;
/* we *could* pass this in as arg, but everyone uses kfree: */
@@ -774,7 +783,10 @@
{
unsigned long flags;
spin_lock_irqsave(&dev->event_lock, flags);
- p->file_priv->event_space += p->event->length;
+ if (p->file_priv) {
+ p->file_priv->event_space += p->event->length;
+ list_del(&p->pending_link);
+ }
spin_unlock_irqrestore(&dev->event_lock, flags);
p->destroy(p);
}
@@ -788,11 +800,22 @@
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. Callers must already hold
* dev->event_lock, see drm_send_event() for the unlocked version.
+ *
+ * Note that the core will take care of unlinking and disarming events when the
+ * corresponding DRM file is closed. Drivers need not worry about whether the
+ * DRM file for this event still exists and can call this function upon
+ * completion of the asynchronous work unconditionally.
*/
void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
{
assert_spin_locked(&dev->event_lock);
+ if (!e->file_priv) {
+ e->destroy(e);
+ return;
+ }
+
+ list_del(&e->pending_link);
list_add_tail(&e->link,
&e->file_priv->event_list);
wake_up_interruptible(&e->file_priv->event_wait);
@@ -807,6 +830,11 @@
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. This function acquires dev->event_lock,
* see drm_send_event_locked() for callers which already hold this lock.
+ *
+ * Note that the core will take care of unlinking and disarming events when the
+ * corresponding DRM file is closed. Drivers need not worry about whether the
+ * DRM file for this event still exists and can call this function upon
+ * completion of the asynchronous work unconditionally.
*/
void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
{