patch-2.4.8 linux/drivers/char/drm/lock.c

• Lines: 253
• Date: Wed Dec 31 16:00:00 1969
• Orig file: v2.4.7/linux/drivers/char/drm/lock.c
• Orig date: Sun Oct 1 20:00:00 2000

diff -u --recursive --new-file v2.4.7/linux/drivers/char/drm/lock.c linux/drivers/char/drm/lock.c
@@ -1,252 +0,0 @@
-/* lock.c -- IOCTLs for locking -*- linux-c -*-
- * Created: Tue Feb  2 08:37:54 1999 by faith@precisioninsight.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
- * PRECISION INSIGHT 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>
- *
- */
-
-#define __NO_VERSION__
-#include "drmP.h"
-
-int drm_block(struct inode *inode, struct file *filp, unsigned int cmd,
-	      unsigned long arg)
-{
-	DRM_DEBUG("\n");
-	return 0;
-}
-
-int drm_unblock(struct inode *inode, struct file *filp, unsigned int cmd,
-		unsigned long arg)
-{
-	DRM_DEBUG("\n");
-	return 0;
-}
-
-int drm_lock_take(__volatile__ unsigned int *lock, unsigned int context)
-{
-	unsigned int old, new, prev;
-
-	do {
-		old = *lock;
-		if (old & _DRM_LOCK_HELD) new = old | _DRM_LOCK_CONT;
-		else			  new = context | _DRM_LOCK_HELD;
-		prev = cmpxchg(lock, old, new);
-	} while (prev != old);
-	if (_DRM_LOCKING_CONTEXT(old) == context) {
-		if (old & _DRM_LOCK_HELD) {
-			if (context != DRM_KERNEL_CONTEXT) {
-				DRM_ERROR("%d holds heavyweight lock\n",
-					  context);
-			}
-			return 0;
-		}
-	}
-	if (new == (context | _DRM_LOCK_HELD)) {
-				/* Have lock */
-		return 1;
-	}
-	return 0;
-}
-
-/* This takes a lock forcibly and hands it to context.	Should ONLY be used
-   inside *_unlock to give lock to kernel before calling *_dma_schedule. */
-int drm_lock_transfer(drm_device_t *dev,
-		      __volatile__ unsigned int *lock, unsigned int context)
-{
-	unsigned int old, new, prev;
-
-	dev->lock.pid = 0;
-	do {
-		old  = *lock;
-		new  = context | _DRM_LOCK_HELD;
-		prev = cmpxchg(lock, old, new);
-	} while (prev != old);
-	return 1;
-}
-
-int drm_lock_free(drm_device_t *dev,
-		  __volatile__ unsigned int *lock, unsigned int context)
-{
-	unsigned int old, new, prev;
-	pid_t        pid = dev->lock.pid;
-
-	dev->lock.pid = 0;
-	do {
-		old  = *lock;
-		new  = 0;
-		prev = cmpxchg(lock, old, new);
-	} while (prev != old);
-	if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) {
-		DRM_ERROR("%d freed heavyweight lock held by %d (pid %d)\n",
-			  context,
-			  _DRM_LOCKING_CONTEXT(old),
-			  pid);
-		return 1;
-	}
-	wake_up_interruptible(&dev->lock.lock_queue);
-	return 0;
-}
-
-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);
-	atomic_inc(&q->total_flushed);
-		
-				/* 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 *)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;
-}
-
-/* If we get here, it means that the process has called DRM_IOCTL_LOCK
-   without calling DRM_IOCTL_UNLOCK.
-   
-   If the lock is not held, then let the signal proceed as usual.
-   
-   If the lock is held, then set the contended flag and keep the signal
-   blocked.
-   
-
-   Return 1 if the signal should be delivered normally.
-   Return 0 if the signal should be blocked.  */
-
-int drm_notifier(void *priv)
-{
-	drm_sigdata_t *s = (drm_sigdata_t *)priv;
-	unsigned int  old, new, prev;
-
-
-				/* Allow signal delivery if lock isn't held */
-	if (!_DRM_LOCK_IS_HELD(s->lock->lock)
-	    || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context) return 1;
-	
-				/* Otherwise, set flag to force call to
-                                   drmUnlock */
-	do {
-		old  = s->lock->lock;
-		new  = old | _DRM_LOCK_CONT;
-		prev = cmpxchg(&s->lock->lock, old, new);
-	} while (prev != old);
-	return 0;
-}