335 lines
8.8 KiB
C
335 lines
8.8 KiB
C
/*
|
|
* 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.
|
|
*/
|
|
|
|
#include <drm/drmP.h>
|
|
#include "drm_internal.h"
|
|
#include "drm_legacy.h"
|
|
|
|
/**
|
|
* 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 the is_master member of &drm_file. 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);
|
|
|
|
return file ? 0 : -EINVAL;
|
|
}
|
|
|
|
static struct drm_master *drm_master_create(struct drm_device *dev)
|
|
{
|
|
struct drm_master *master;
|
|
|
|
master = kzalloc(sizeof(*master), GFP_KERNEL);
|
|
if (!master)
|
|
return NULL;
|
|
|
|
kref_init(&master->refcount);
|
|
spin_lock_init(&master->lock.spinlock);
|
|
init_waitqueue_head(&master->lock.lock_queue);
|
|
idr_init(&master->magic_map);
|
|
master->dev = dev;
|
|
|
|
return master;
|
|
}
|
|
|
|
static int drm_set_master(struct drm_device *dev, struct drm_file *fpriv,
|
|
bool new_master)
|
|
{
|
|
int ret = 0;
|
|
|
|
dev->master = drm_master_get(fpriv->master);
|
|
if (dev->driver->master_set) {
|
|
ret = dev->driver->master_set(dev, fpriv, new_master);
|
|
if (unlikely(ret != 0)) {
|
|
drm_master_put(&dev->master);
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int drm_new_set_master(struct drm_device *dev, struct drm_file *fpriv)
|
|
{
|
|
struct drm_master *old_master;
|
|
int ret;
|
|
|
|
lockdep_assert_held_once(&dev->master_mutex);
|
|
|
|
old_master = fpriv->master;
|
|
fpriv->master = drm_master_create(dev);
|
|
if (!fpriv->master) {
|
|
fpriv->master = old_master;
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (dev->driver->master_create) {
|
|
ret = dev->driver->master_create(dev, fpriv->master);
|
|
if (ret)
|
|
goto out_err;
|
|
}
|
|
fpriv->is_master = 1;
|
|
fpriv->authenticated = 1;
|
|
|
|
ret = drm_set_master(dev, fpriv, true);
|
|
if (ret)
|
|
goto out_err;
|
|
|
|
if (old_master)
|
|
drm_master_put(&old_master);
|
|
|
|
return 0;
|
|
|
|
out_err:
|
|
/* drop references and restore old master on failure */
|
|
drm_master_put(&fpriv->master);
|
|
fpriv->master = old_master;
|
|
|
|
return ret;
|
|
}
|
|
|
|
int drm_setmaster_ioctl(struct drm_device *dev, void *data,
|
|
struct drm_file *file_priv)
|
|
{
|
|
int ret = 0;
|
|
|
|
mutex_lock(&dev->master_mutex);
|
|
if (drm_is_current_master(file_priv))
|
|
goto out_unlock;
|
|
|
|
if (dev->master) {
|
|
ret = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (!file_priv->master) {
|
|
ret = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (!file_priv->is_master) {
|
|
ret = drm_new_set_master(dev, file_priv);
|
|
goto out_unlock;
|
|
}
|
|
|
|
ret = drm_set_master(dev, file_priv, false);
|
|
out_unlock:
|
|
mutex_unlock(&dev->master_mutex);
|
|
return ret;
|
|
}
|
|
|
|
static void drm_drop_master(struct drm_device *dev,
|
|
struct drm_file *fpriv)
|
|
{
|
|
if (dev->driver->master_drop)
|
|
dev->driver->master_drop(dev, fpriv);
|
|
drm_master_put(&dev->master);
|
|
}
|
|
|
|
int drm_dropmaster_ioctl(struct drm_device *dev, void *data,
|
|
struct drm_file *file_priv)
|
|
{
|
|
int ret = -EINVAL;
|
|
|
|
mutex_lock(&dev->master_mutex);
|
|
if (!drm_is_current_master(file_priv))
|
|
goto out_unlock;
|
|
|
|
if (!dev->master)
|
|
goto out_unlock;
|
|
|
|
ret = 0;
|
|
drm_drop_master(dev, file_priv);
|
|
out_unlock:
|
|
mutex_unlock(&dev->master_mutex);
|
|
return ret;
|
|
}
|
|
|
|
int drm_master_open(struct drm_file *file_priv)
|
|
{
|
|
struct drm_device *dev = file_priv->minor->dev;
|
|
int ret = 0;
|
|
|
|
/* if there is no current master make this fd it, but do not create
|
|
* any master object for render clients */
|
|
mutex_lock(&dev->master_mutex);
|
|
if (!dev->master)
|
|
ret = drm_new_set_master(dev, file_priv);
|
|
else
|
|
file_priv->master = drm_master_get(dev->master);
|
|
mutex_unlock(&dev->master_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void drm_master_release(struct drm_file *file_priv)
|
|
{
|
|
struct drm_device *dev = file_priv->minor->dev;
|
|
struct drm_master *master = file_priv->master;
|
|
|
|
mutex_lock(&dev->master_mutex);
|
|
if (file_priv->magic)
|
|
idr_remove(&file_priv->master->magic_map, file_priv->magic);
|
|
|
|
if (!drm_is_current_master(file_priv))
|
|
goto out;
|
|
|
|
if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
|
|
/*
|
|
* Since the master is disappearing, so is the
|
|
* possibility to lock.
|
|
*/
|
|
mutex_lock(&dev->struct_mutex);
|
|
if (master->lock.hw_lock) {
|
|
if (dev->sigdata.lock == master->lock.hw_lock)
|
|
dev->sigdata.lock = NULL;
|
|
master->lock.hw_lock = NULL;
|
|
master->lock.file_priv = NULL;
|
|
wake_up_interruptible_all(&master->lock.lock_queue);
|
|
}
|
|
mutex_unlock(&dev->struct_mutex);
|
|
}
|
|
|
|
if (dev->master == file_priv->master)
|
|
drm_drop_master(dev, file_priv);
|
|
out:
|
|
/* drop the master reference held by the file priv */
|
|
if (file_priv->master)
|
|
drm_master_put(&file_priv->master);
|
|
mutex_unlock(&dev->master_mutex);
|
|
}
|
|
|
|
/**
|
|
* drm_is_current_master - checks whether @priv is the current master
|
|
* @fpriv: DRM file private
|
|
*
|
|
* Checks whether @fpriv is current master on its device. This decides whether a
|
|
* client is allowed to run DRM_MASTER IOCTLs.
|
|
*
|
|
* Most of the modern IOCTL which require DRM_MASTER are for kernel modesetting
|
|
* - the current master is assumed to own the non-shareable display hardware.
|
|
*/
|
|
bool drm_is_current_master(struct drm_file *fpriv)
|
|
{
|
|
return fpriv->is_master && fpriv->master == fpriv->minor->dev->master;
|
|
}
|
|
EXPORT_SYMBOL(drm_is_current_master);
|
|
|
|
/**
|
|
* drm_master_get - reference a master pointer
|
|
* @master: struct &drm_master
|
|
*
|
|
* Increments the reference count of @master and returns a pointer to @master.
|
|
*/
|
|
struct drm_master *drm_master_get(struct drm_master *master)
|
|
{
|
|
kref_get(&master->refcount);
|
|
return master;
|
|
}
|
|
EXPORT_SYMBOL(drm_master_get);
|
|
|
|
static void drm_master_destroy(struct kref *kref)
|
|
{
|
|
struct drm_master *master = container_of(kref, struct drm_master, refcount);
|
|
struct drm_device *dev = master->dev;
|
|
|
|
if (dev->driver->master_destroy)
|
|
dev->driver->master_destroy(dev, master);
|
|
|
|
drm_legacy_master_rmmaps(dev, master);
|
|
|
|
idr_destroy(&master->magic_map);
|
|
kfree(master->unique);
|
|
kfree(master);
|
|
}
|
|
|
|
/**
|
|
* drm_master_put - unreference and clear a master pointer
|
|
* @master: pointer to a pointer of struct &drm_master
|
|
*
|
|
* This decrements the &drm_master behind @master and sets it to NULL.
|
|
*/
|
|
void drm_master_put(struct drm_master **master)
|
|
{
|
|
kref_put(&(*master)->refcount, drm_master_destroy);
|
|
*master = NULL;
|
|
}
|
|
EXPORT_SYMBOL(drm_master_put);
|