/* lock.c -- IOCTLs for locking -*- linux-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.
*
* 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.
*
* Authors:
* Rickard E. (Rik) Faith <faith@valinux.com>
* Gareth Hughes <gareth@valinux.com>
*/
/* Gamma-specific code extracted from drm_lock.h:
*/
static int DRM(flush_queue)(drm_device_t *dev, int context)
{
DECLARE_WAITQUEUE(entry, current);
int ret = 0;
drm_queue_t *q = dev->queuelist[context];
DRM_DEBUG("\n");
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) > 1) {
atomic_inc(&q->block_write);
add_wait_queue(&q->flush_queue, &entry);
atomic_inc(&q->block_count);
for (;;) {
current->state = TASK_INTERRUPTIBLE;
if (!DRM_BUFCOUNT(&q->waitlist)) break;
schedule();
if (signal_pending(current)) {
ret = -EINTR; /* Can't restart */
break;
}
}
atomic_dec(&q->block_count);
current->state = TASK_RUNNING;
remove_wait_queue(&q->flush_queue, &entry);
}
atomic_dec(&q->use_count);
/* NOTE: block_write is still incremented!
Use drm_flush_unlock_queue to decrement. */
return ret;
}
static int DRM(flush_unblock_queue)(drm_device_t *dev, int context)
{
drm_queue_t *q = dev->queuelist[context];
DRM_DEBUG("\n");
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) > 1) {
if (atomic_read(&q->block_write)) {
atomic_dec(&q->block_write);
wake_up_interruptible(&q->write_queue);
}
}
atomic_dec(&q->use_count);
return 0;
}
int DRM(flush_block_and_flush)(drm_device_t *dev, int context,
drm_lock_flags_t flags)
{
int ret = 0;
int i;
DRM_DEBUG("\n");
if (flags & _DRM_LOCK_FLUSH) {
ret = DRM(flush_queue)(dev, DRM_KERNEL_CONTEXT);
if (!ret) ret = DRM(flush_queue)(dev, context);
}
if (flags & _DRM_LOCK_FLUSH_ALL) {
for (i = 0; !ret && i < dev->queue_count; i++) {
ret = DRM(flush_queue)(dev, i);
}
}
return ret;
}
int DRM(flush_unblock)(drm_device_t *dev, int context, drm_lock_flags_t flags)
{
int ret = 0;
int i;
DRM_DEBUG("\n");
if (flags & _DRM_LOCK_FLUSH) {
ret = DRM(flush_unblock_queue)(dev, DRM_KERNEL_CONTEXT);
if (!ret) ret = DRM(flush_unblock_queue)(dev, context);
}
if (flags & _DRM_LOCK_FLUSH_ALL) {
for (i = 0; !ret && i < dev->queue_count; i++) {
ret = DRM(flush_unblock_queue)(dev, i);
}
}
return ret;
}
int DRM(finish)(struct inode *inode, struct file *filp, unsigned int cmd,
unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
int ret = 0;
drm_lock_t lock;
DRM_DEBUG("\n");
if (copy_from_user(&lock, (drm_lock_t __user *)arg, sizeof(lock)))
return -EFAULT;
ret = DRM(flush_block_and_flush)(dev, lock.context, lock.flags);
DRM(flush_unblock)(dev, lock.context, lock.flags);
return ret;
}
