From 48e7f18392c66f9b69ebac11c54f1a2e033ced54 Mon Sep 17 00:00:00 2001 From: "Kristian H. Kristensen" Date: Wed, 20 Mar 2019 10:09:08 -0700 Subject: drm/msm: Implement .gem_free_object_unlocked We use a llist and a worker to delay the object cleanup. This avoids taking mmap_sem and struct_mutex in the wrong order when calling drm_gem_object_put_unlocked() from drm_gem_mmap(). Fixes lockdep problem with copy_from_user() in msm_ioctl_gem_submit(). Signed-off-by: Kristian H. Kristensen Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/msm_gem.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/msm/msm_gem.c') diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 76940a9da980..d4dae0f0238e 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -853,8 +853,18 @@ void msm_gem_describe_objects(struct list_head *list, struct seq_file *m) /* don't call directly! Use drm_gem_object_put() and friends */ void msm_gem_free_object(struct drm_gem_object *obj) { - struct drm_device *dev = obj->dev; struct msm_gem_object *msm_obj = to_msm_bo(obj); + struct drm_device *dev = obj->dev; + struct msm_drm_private *priv = dev->dev_private; + + if (llist_add(&msm_obj->freed, &priv->free_list)) + queue_work(priv->wq, &priv->free_work); +} + +static void free_object(struct msm_gem_object *msm_obj) +{ + struct drm_gem_object *obj = &msm_obj->base; + struct drm_device *dev = obj->dev; WARN_ON(!mutex_is_locked(&dev->struct_mutex)); @@ -892,6 +902,29 @@ void msm_gem_free_object(struct drm_gem_object *obj) kfree(msm_obj); } +void msm_gem_free_work(struct work_struct *work) +{ + struct msm_drm_private *priv = + container_of(work, struct msm_drm_private, free_work); + struct drm_device *dev = priv->dev; + struct llist_node *freed; + struct msm_gem_object *msm_obj, *next; + + while ((freed = llist_del_all(&priv->free_list))) { + + mutex_lock(&dev->struct_mutex); + + llist_for_each_entry_safe(msm_obj, next, + freed, freed) + free_object(msm_obj); + + mutex_unlock(&dev->struct_mutex); + + if (need_resched()) + break; + } +} + /* convenience method to construct a GEM buffer object, and userspace handle */ int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file, uint32_t size, uint32_t flags, uint32_t *handle, -- cgit v1.2.3