43  * DOC: master and authentication
47  * least once successfully became the device master (either through the
49  * no one else is the current master that time) there exists one &drm_master.
53  * In addition only one &drm_master can be the current master for a &drm_device.
58  * Clients can authenticate against the current master (if it matches their own)
71 		ret = idr_alloc(&file_priv->master->magic_map, file_priv,  in drm_getmagic()
93 	file = idr_find(&file_priv->master->magic_map, auth->magic);  in drm_authmagic()
96 		idr_replace(&file_priv->master->magic_map, NULL, auth->magic);  in drm_authmagic()
105 	struct drm_master *master;  in drm_master_create()  local
107 	master = kzalloc(sizeof(*master), GFP_KERNEL);  in drm_master_create()
108 	if (!master)  in drm_master_create()
111 	kref_init(&master->refcount);  in drm_master_create()
112 	drm_master_legacy_init(master);  in drm_master_create()
113 	idr_init(&master->magic_map);  in drm_master_create()
114 	master->dev = dev;  in drm_master_create()
117 	INIT_LIST_HEAD(&master->lessees);  in drm_master_create()
118 	INIT_LIST_HEAD(&master->lessee_list);  in drm_master_create()
119 	idr_init(&master->leases);  in drm_master_create()
120 	idr_init(&master->lessee_idr);  in drm_master_create()
122 	return master;  in drm_master_create()
128 	dev->master = drm_master_get(fpriv->master);  in drm_set_master()
143 	old_master = fpriv->master;  in drm_new_set_master()
148 	fpriv->master = new_master;  in drm_new_set_master()
165  * from becoming master and/or failing to release it.
167  * At the same time, the first client (for a given VT) is _always_ master.
171  * If the CAP_SYS_ADMIN was missing, no other client could become master...
177  * master as applicable. It does so by opening the fd and passing it to users
178  * while in itself logind a) does the set/drop master per users' request and
179  * b)  * implicitly drops master on VT switch.
183  * root is required _solely_ for SET/DROP MASTER.
185  *  - any client which fails to drop master* can DoS the application using
193  *  - allow a client to drop/set master, iff it is/was master at a given point
198  *  - open the node, become master implicitly and cause issues
231 	if (dev->master) {  in drm_setmaster_ioctl()
236 	if (!file_priv->master) {  in drm_setmaster_ioctl()
246 	if (file_priv->master->lessor != NULL) {  in drm_setmaster_ioctl()
247 		DRM_DEBUG_LEASE("Attempt to set lessee %d as master\n", file_priv->master->lessee_id);  in drm_setmaster_ioctl()
263 	drm_master_put(&dev->master);  in drm_drop_master()
282 	if (!dev->master) {  in drm_dropmaster_ioctl()
287 	if (file_priv->master->lessor != NULL) {  in drm_dropmaster_ioctl()
288 		DRM_DEBUG_LEASE("Attempt to drop lessee %d as master\n", file_priv->master->lessee_id);  in drm_dropmaster_ioctl()
304 	/* if there is no current master make this fd it, but do not create  in drm_master_open()
305 	 * any master object for render clients */  in drm_master_open()
307 	if (!dev->master) {  in drm_master_open()
311 		file_priv->master = drm_master_get(dev->master);  in drm_master_open()
322 	struct drm_master *master;  in drm_master_release()  local
325 	master = file_priv->master;  in drm_master_release()
327 		idr_remove(&file_priv->master->magic_map, file_priv->magic);  in drm_master_release()
332 	drm_legacy_lock_master_cleanup(dev, master);  in drm_master_release()
334 	if (dev->master == file_priv->master)  in drm_master_release()
339 		 * this is the "real" master  in drm_master_release()
341 		drm_lease_revoke(master);  in drm_master_release()
344 	/* drop the master reference held by the file priv */  in drm_master_release()
345 	if (file_priv->master)  in drm_master_release()
346 		drm_master_put(&file_priv->master);  in drm_master_release()
351  * drm_is_current_master - checks whether @priv is the current master
354  * Checks whether @fpriv is current master on its device. This decides whether a
358  * - the current master is assumed to own the non-shareable display hardware.
362 	return fpriv->is_master && drm_lease_owner(fpriv->master) == fpriv->minor->dev->master;  in drm_is_current_master()
367  * drm_master_get - reference a master pointer
368  * @master: &struct drm_master
370  * Increments the reference count of @master and returns a pointer to @master.
372 struct drm_master *drm_master_get(struct drm_master *master)  in drm_master_get()  argument
374 	kref_get(&master->refcount);  in drm_master_get()
375 	return master;  in drm_master_get()
380  * drm_file_get_master - reference &drm_file.master of @file_priv
383  * Increments the reference count of @file_priv's &drm_file.master and returns
384  * the &drm_file.master. If @file_priv has no &drm_file.master, returns NULL.
386  * Master pointers returned from this function should be unreferenced using
391 	struct drm_master *master = NULL;  in drm_file_get_master()  local
394 	if (!file_priv->master)  in drm_file_get_master()
396 	master = drm_master_get(file_priv->master);  in drm_file_get_master()
400 	return master;  in drm_file_get_master()
406 	struct drm_master *master = container_of(kref, struct drm_master, refcount);  in drm_master_destroy()  local
407 	struct drm_device *dev = master->dev;  in drm_master_destroy()
410 		drm_lease_destroy(master);  in drm_master_destroy()
412 	drm_legacy_master_rmmaps(dev, master);  in drm_master_destroy()
414 	idr_destroy(&master->magic_map);  in drm_master_destroy()
415 	idr_destroy(&master->leases);  in drm_master_destroy()
416 	idr_destroy(&master->lessee_idr);  in drm_master_destroy()
418 	kfree(master->unique);  in drm_master_destroy()
419 	kfree(master);  in drm_master_destroy()
423  * drm_master_put - unreference and clear a master pointer
424  * @master: pointer to a pointer of &struct drm_master
426  * This decrements the &drm_master behind @master and sets it to NULL.
428 void drm_master_put(struct drm_master **master)  in drm_master_put()  argument
430 	kref_put(&(*master)->refcount, drm_master_destroy);  in drm_master_put()
431 	*master = NULL;  in drm_master_put()
439 	if (dev->master) {  in drm_master_internal_acquire()