Source
x
DRM_DEBUG_LEASE("Attempt to drop lessee %d as master\n", file_priv->master->lessee_id);
/*
* Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
*
* Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Author Rickard E. (Rik) Faith <faith@valinux.com>
* Author Gareth Hughes <gareth@valinux.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* DOC: master and authentication
*
* &struct drm_master is used to track groups of clients with open
* primary/legacy device nodes. For every &struct drm_file which has had at
* least once successfully became the device master (either through the
* SET_MASTER IOCTL, or implicitly through opening the primary device node when
* no one else is the current master that time) there exists one &drm_master.
* This is noted in &drm_file.is_master. All other clients have just a pointer
* to the &drm_master they are associated with.
*
* In addition only one &drm_master can be the current master for a &drm_device.
* It can be switched through the DROP_MASTER and SET_MASTER IOCTL, or
* implicitly through closing/openeing the primary device node. See also
* drm_is_current_master().
*
* Clients can authenticate against the current master (if it matches their own)
* using the GETMAGIC and AUTHMAGIC IOCTLs. Together with exchanging masters,
* this allows controlled access to the device for an entire group of mutually
* trusted clients.
*/
int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
struct drm_auth *auth = data;
int ret = 0;
mutex_lock(&dev->master_mutex);
if (!file_priv->magic) {
ret = idr_alloc(&file_priv->master->magic_map, file_priv,
1, 0, GFP_KERNEL);
if (ret >= 0)
file_priv->magic = ret;
}
auth->magic = file_priv->magic;
mutex_unlock(&dev->master_mutex);
DRM_DEBUG("%u\n", auth->magic);
return ret < 0 ? ret : 0;
}
int drm_authmagic(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_auth *auth = data;
struct drm_file *file;
DRM_DEBUG("%u\n", auth->magic);
mutex_lock(&dev->master_mutex);
file = idr_find(&file_priv->master->magic_map, auth->magic);
if (file) {
file->authenticated = 1;
idr_replace(&file_priv->master->magic_map, NULL, auth->magic);
}
mutex_unlock(&dev->master_mutex);