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) Link: http://patchwork.freedesktop.org/patch/msgid/1452548477-15905-10-git-send-em... Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_fops.c | 30 +++++++++++++++++++++++++++++- include/drm/drmP.h | 2 ++ 2 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index eb6a02f78697..afe8c53e5aad 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -264,6 +264,7 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor) 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 @@ static void drm_events_release(struct drm_file *file_priv) 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 @@ int drm_event_reserve_init_locked(struct drm_device *dev, 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 @@ void drm_event_cancel_free(struct drm_device *dev, { 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 @@ EXPORT_SYMBOL(drm_event_cancel_free); * 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 @@ EXPORT_SYMBOL(drm_send_event_locked); * 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) { diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 1b71852d0a55..3c8422c69572 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -283,6 +283,7 @@ struct drm_ioctl_desc { struct drm_pending_event { struct drm_event *event; struct list_head link; + struct list_head pending_link; struct drm_file *file_priv; pid_t pid; /* pid of requester, no guarantee it's valid by the time we deliver the event, for tracing only */ @@ -346,6 +347,7 @@ struct drm_file { struct list_head blobs;
wait_queue_head_t event_wait; + struct list_head pending_event_list; struct list_head event_list; int event_space;