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()
142 	old_master = fpriv->master;  in drm_new_set_master()
143 	fpriv->master = drm_master_create(dev);  in drm_new_set_master()
144 	if (!fpriv->master) {  in drm_new_set_master()
145 		fpriv->master = old_master;  in drm_new_set_master()
163  * from becoming master and/or failing to release it.
165  * At the same time, the first client (for a given VT) is _always_ master.
169  * If the CAP_SYS_ADMIN was missing, no other client could become master...
175  * master as applicable. It does so by opening the fd and passing it to users
176  * while in itself logind a) does the set/drop master per users' request and
177  * b)  * implicitly drops master on VT switch.
181  * root is required _solely_ for SET/DROP MASTER.
183  *  - any client which fails to drop master* can DoS the application using
191  *  - allow a client to drop/set master, iff it is/was master at a given point
196  *  - open the node, become master implicitly and cause issues
229 	if (dev->master) {  in drm_setmaster_ioctl()
234 	if (!file_priv->master) {  in drm_setmaster_ioctl()
244 	if (file_priv->master->lessor != NULL) {  in drm_setmaster_ioctl()
245 		DRM_DEBUG_LEASE("Attempt to set lessee %d as master\n", file_priv->master->lessee_id);  in drm_setmaster_ioctl()
261 	drm_master_put(&dev->master);  in drm_drop_master()
280 	if (!dev->master) {  in drm_dropmaster_ioctl()
285 	if (file_priv->master->lessor != NULL) {  in drm_dropmaster_ioctl()
286 		DRM_DEBUG_LEASE("Attempt to drop lessee %d as master\n", file_priv->master->lessee_id);  in drm_dropmaster_ioctl()
302 	/* if there is no current master make this fd it, but do not create  in drm_master_open()
303 	 * any master object for render clients */  in drm_master_open()
305 	if (!dev->master)  in drm_master_open()
308 		file_priv->master = drm_master_get(dev->master);  in drm_master_open()
317 	struct drm_master *master = file_priv->master;  in drm_master_release()  local
321 		idr_remove(&file_priv->master->magic_map, file_priv->magic);  in drm_master_release()
326 	drm_legacy_lock_master_cleanup(dev, master);  in drm_master_release()
328 	if (dev->master == file_priv->master)  in drm_master_release()
333 		 * this is the "real" master  in drm_master_release()
335 		drm_lease_revoke(master);  in drm_master_release()
338 	/* drop the master reference held by the file priv */  in drm_master_release()
339 	if (file_priv->master)  in drm_master_release()
340 		drm_master_put(&file_priv->master);  in drm_master_release()
345  * drm_is_current_master - checks whether @priv is the current master
348  * Checks whether @fpriv is current master on its device. This decides whether a
352  * - the current master is assumed to own the non-shareable display hardware.
356 	return fpriv->is_master && drm_lease_owner(fpriv->master) == fpriv->minor->dev->master;  in drm_is_current_master()
361  * drm_master_get - reference a master pointer
362  * @master: &struct drm_master
364  * Increments the reference count of @master and returns a pointer to @master.
366 struct drm_master *drm_master_get(struct drm_master *master)  in drm_master_get()  argument
368 	kref_get(&master->refcount);  in drm_master_get()
369 	return master;  in drm_master_get()
375 	struct drm_master *master = container_of(kref, struct drm_master, refcount);  in drm_master_destroy()  local
376 	struct drm_device *dev = master->dev;  in drm_master_destroy()
379 		drm_lease_destroy(master);  in drm_master_destroy()
381 	drm_legacy_master_rmmaps(dev, master);  in drm_master_destroy()
383 	idr_destroy(&master->magic_map);  in drm_master_destroy()
384 	idr_destroy(&master->leases);  in drm_master_destroy()
385 	idr_destroy(&master->lessee_idr);  in drm_master_destroy()
387 	kfree(master->unique);  in drm_master_destroy()
388 	kfree(master);  in drm_master_destroy()
392  * drm_master_put - unreference and clear a master pointer
393  * @master: pointer to a pointer of &struct drm_master
395  * This decrements the &drm_master behind @master and sets it to NULL.
397 void drm_master_put(struct drm_master **master)  in drm_master_put()  argument
399 	kref_put(&(*master)->refcount, drm_master_destroy);  in drm_master_put()
400 	*master = NULL;  in drm_master_put()
408 	if (dev->master) {  in drm_master_internal_acquire()