drm_drv.h

来自「优龙2410linux2.6.8内核源代码」· C头文件 代码 · 共 1,210 行 · 第 1/3 页

	}

	return retcode;
}

/**
 * Release file.
 *
 * \param inode device inode
 * \param filp file pointer.
 * \return zero on success or a negative number on failure.
 *
 * If the hardware lock is held then free it, and take it again for the kernel
 * context since it's necessary to reclaim buffers. Unlink the file private
 * data from its list and free it. Decreases the open count and if it reaches
 * zero calls takedown().
 */
int DRM(release)( struct inode *inode, struct file *filp )
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev;
	int retcode = 0;

	lock_kernel();
	dev = priv->dev;

	DRM_DEBUG( "open_count = %d\n", dev->open_count );

	DRIVER_PRERELEASE();

	/* ========================================================
	 * Begin inline drm_release
	 */

	DRM_DEBUG( "pid = %d, device = 0x%lx, open_count = %d\n",
		   current->pid, (long)old_encode_dev(dev->device), dev->open_count );

	if ( priv->lock_count && dev->lock.hw_lock &&
	     _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
	     dev->lock.filp == filp ) {
		DRM_DEBUG( "File %p released, freeing lock for context %d\n",
			filp,
			_DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
#if __HAVE_RELEASE
		DRIVER_RELEASE();
#endif
		DRM(lock_free)( dev, &dev->lock.hw_lock->lock,
				_DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );

				/* FIXME: may require heavy-handed reset of
                                   hardware at this point, possibly
                                   processed via a callback to the X
                                   server. */
	}
#if __HAVE_RELEASE
	else if ( priv->lock_count && dev->lock.hw_lock ) {
		/* The lock is required to reclaim buffers */
		DECLARE_WAITQUEUE( entry, current );

		add_wait_queue( &dev->lock.lock_queue, &entry );
		for (;;) {
			current->state = TASK_INTERRUPTIBLE;
			if ( !dev->lock.hw_lock ) {
				/* Device has been unregistered */
				retcode = -EINTR;
				break;
			}
			if ( DRM(lock_take)( &dev->lock.hw_lock->lock,
					     DRM_KERNEL_CONTEXT ) ) {
				dev->lock.filp	    = filp;
				dev->lock.lock_time = jiffies;
                                atomic_inc( &dev->counts[_DRM_STAT_LOCKS] );
				break;	/* Got lock */
			}
				/* Contention */
			schedule();
			if ( signal_pending( current ) ) {
				retcode = -ERESTARTSYS;
				break;
			}
		}
		current->state = TASK_RUNNING;
		remove_wait_queue( &dev->lock.lock_queue, &entry );
		if( !retcode ) {
			DRIVER_RELEASE();
			DRM(lock_free)( dev, &dev->lock.hw_lock->lock,
					DRM_KERNEL_CONTEXT );
		}
	}
#elif __HAVE_DMA
	DRM(reclaim_buffers)( filp );
#endif

	DRM(fasync)( -1, filp, 0 );

	down( &dev->ctxlist_sem );
	if ( !list_empty( &dev->ctxlist->head ) ) {
		drm_ctx_list_t *pos, *n;

		list_for_each_entry_safe( pos, n, &dev->ctxlist->head, head ) {
			if ( pos->tag == priv &&
			     pos->handle != DRM_KERNEL_CONTEXT ) {
#ifdef DRIVER_CTX_DTOR
				DRIVER_CTX_DTOR(pos->handle);
#endif
#if __HAVE_CTX_BITMAP
				DRM(ctxbitmap_free)( dev, pos->handle );
#endif
				list_del( &pos->head );
				DRM(free)( pos, sizeof(*pos), DRM_MEM_CTXLIST );
			}
		}
	}
	up( &dev->ctxlist_sem );

	down( &dev->struct_sem );
	if ( priv->remove_auth_on_close == 1 ) {
		drm_file_t *temp = dev->file_first;
		while ( temp ) {
			temp->authenticated = 0;
			temp = temp->next;
		}
	}
	if ( priv->prev ) {
		priv->prev->next = priv->next;
	} else {
		dev->file_first	 = priv->next;
	}
	if ( priv->next ) {
		priv->next->prev = priv->prev;
	} else {
		dev->file_last	 = priv->prev;
	}
	up( &dev->struct_sem );
	
	DRM(free)( priv, sizeof(*priv), DRM_MEM_FILES );

	/* ========================================================
	 * End inline drm_release
	 */

	atomic_inc( &dev->counts[_DRM_STAT_CLOSES] );
	spin_lock( &dev->count_lock );
	if ( !--dev->open_count ) {
		if ( atomic_read( &dev->ioctl_count ) || dev->blocked ) {
			DRM_ERROR( "Device busy: %d %d\n",
				   atomic_read( &dev->ioctl_count ),
				   dev->blocked );
			spin_unlock( &dev->count_lock );
			unlock_kernel();
			return -EBUSY;
		}
		spin_unlock( &dev->count_lock );
		unlock_kernel();
		return DRM(takedown)( dev );
	}
	spin_unlock( &dev->count_lock );

	unlock_kernel();

	return retcode;
}

/** 
 * Called whenever a process performs an ioctl on /dev/drm.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument.
 * \return zero on success or negative number on failure.
 *
 * Looks up the ioctl function in the ::ioctls table, checking for root
 * previleges if so required, and dispatches to the respective function.
 */
int DRM(ioctl)( 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;
	drm_ioctl_desc_t *ioctl;
	drm_ioctl_t *func;
	int nr = DRM_IOCTL_NR(cmd);
	int retcode = 0;

	atomic_inc( &dev->ioctl_count );
	atomic_inc( &dev->counts[_DRM_STAT_IOCTLS] );
	++priv->ioctl_count;

	DRM_DEBUG( "pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
		   current->pid, cmd, nr, (long)old_encode_dev(dev->device), 
		   priv->authenticated );

	if ( nr >= DRIVER_IOCTL_COUNT ) {
		retcode = -EINVAL;
	} else {
		ioctl = &DRM(ioctls)[nr];
		func = ioctl->func;

		if ( !func ) {
			DRM_DEBUG( "no function\n" );
			retcode = -EINVAL;
		} else if ( ( ioctl->root_only && !capable( CAP_SYS_ADMIN ) )||
			    ( ioctl->auth_needed && !priv->authenticated ) ) {
			retcode = -EACCES;
		} else {
			retcode = func( inode, filp, cmd, arg );
		}
	}

	atomic_dec( &dev->ioctl_count );
	return retcode;
}

/** 
 * Lock ioctl.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_lock structure.
 * \return zero on success or negative number on failure.
 *
 * Add the current task to the lock wait queue, and attempt to take to lock.
 */
int DRM(lock)( 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;
        DECLARE_WAITQUEUE( entry, current );
        drm_lock_t lock;
        int ret = 0;
#if __HAVE_MULTIPLE_DMA_QUEUES
	drm_queue_t *q;
#endif

	++priv->lock_count;

        if ( copy_from_user( &lock, (drm_lock_t __user *)arg, sizeof(lock) ) )
		return -EFAULT;

        if ( lock.context == DRM_KERNEL_CONTEXT ) {
                DRM_ERROR( "Process %d using kernel context %d\n",
			   current->pid, lock.context );
                return -EINVAL;
        }

        DRM_DEBUG( "%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
		   lock.context, current->pid,
		   dev->lock.hw_lock->lock, lock.flags );

#if __HAVE_DMA_QUEUE
        if ( lock.context < 0 )
                return -EINVAL;
#elif __HAVE_MULTIPLE_DMA_QUEUES
        if ( lock.context < 0 || lock.context >= dev->queue_count )
                return -EINVAL;
	q = dev->queuelist[lock.context];
#endif

#if __HAVE_DMA_FLUSH
	ret = DRM(flush_block_and_flush)( dev, lock.context, lock.flags );
#endif
        if ( !ret ) {
                add_wait_queue( &dev->lock.lock_queue, &entry );
                for (;;) {
                        current->state = TASK_INTERRUPTIBLE;
                        if ( !dev->lock.hw_lock ) {
                                /* Device has been unregistered */
                                ret = -EINTR;
                                break;
                        }
                        if ( DRM(lock_take)( &dev->lock.hw_lock->lock,
					     lock.context ) ) {
                                dev->lock.filp      = filp;
                                dev->lock.lock_time = jiffies;
                                atomic_inc( &dev->counts[_DRM_STAT_LOCKS] );
                                break;  /* Got lock */
                        }

                                /* Contention */
                        schedule();
                        if ( signal_pending( current ) ) {
                                ret = -ERESTARTSYS;
                                break;
                        }
                }
                current->state = TASK_RUNNING;
                remove_wait_queue( &dev->lock.lock_queue, &entry );
        }

#if __HAVE_DMA_FLUSH
	DRM(flush_unblock)( dev, lock.context, lock.flags ); /* cleanup phase */
#endif

        if ( !ret ) {
		sigemptyset( &dev->sigmask );
		sigaddset( &dev->sigmask, SIGSTOP );
		sigaddset( &dev->sigmask, SIGTSTP );
		sigaddset( &dev->sigmask, SIGTTIN );
		sigaddset( &dev->sigmask, SIGTTOU );
		dev->sigdata.context = lock.context;
		dev->sigdata.lock    = dev->lock.hw_lock;
		block_all_signals( DRM(notifier),
				   &dev->sigdata, &dev->sigmask );

#if __HAVE_DMA_READY
                if ( lock.flags & _DRM_LOCK_READY ) {
			DRIVER_DMA_READY();
		}
#endif
#if __HAVE_DMA_QUIESCENT
                if ( lock.flags & _DRM_LOCK_QUIESCENT ) {
			DRIVER_DMA_QUIESCENT();
		}
#endif
		/* __HAVE_KERNEL_CTX_SWITCH isn't used by any of the
		 * drm modules in the DRI cvs tree, but it is required
		 * by the Sparc driver.
		 */
#if __HAVE_KERNEL_CTX_SWITCH
		if ( dev->last_context != lock.context ) {
			DRM(context_switch)(dev, dev->last_context,
					    lock.context);
		}
#endif
        }

        DRM_DEBUG( "%d %s\n", lock.context, ret ? "interrupted" : "has lock" );

        return ret;
}

/** 
 * Unlock ioctl.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_lock structure.
 * \return zero on success or negative number on failure.
 *
 * Transfer and free the lock.
 */
int DRM(unlock)( 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;
	drm_lock_t lock;

	if ( copy_from_user( &lock, (drm_lock_t __user *)arg, sizeof(lock) ) )
		return -EFAULT;

	if ( lock.context == DRM_KERNEL_CONTEXT ) {
		DRM_ERROR( "Process %d using kernel context %d\n",
			   current->pid, lock.context );
		return -EINVAL;
	}

	atomic_inc( &dev->counts[_DRM_STAT_UNLOCKS] );

	/* __HAVE_KERNEL_CTX_SWITCH isn't used by any of the drm
	 * modules in the DRI cvs tree, but it is required by the
	 * Sparc driver.
	 */
#if __HAVE_KERNEL_CTX_SWITCH
	/* We no longer really hold it, but if we are the next
	 * agent to request it then we should just be able to
	 * take it immediately and not eat the ioctl.
	 */
	dev->lock.filp = NULL;
	{
		__volatile__ unsigned int *plock = &dev->lock.hw_lock->lock;
		unsigned int old, new, prev, ctx;

		ctx = lock.context;
		do {
			old  = *plock;
			new  = ctx;
			prev = cmpxchg(plock, old, new);
		} while (prev != old);
	}
	wake_up_interruptible(&dev->lock.lock_queue);
#else
	DRM(lock_transfer)( dev, &dev->lock.hw_lock->lock,
			    DRM_KERNEL_CONTEXT );
#if __HAVE_DMA_SCHEDULE
	DRM(dma_schedule)( dev, 1 );
#endif

	if ( DRM(lock_free)( dev, &dev->lock.hw_lock->lock,
			     DRM_KERNEL_CONTEXT ) ) {
		DRM_ERROR( "\n" );
	}
#endif /* !__HAVE_KERNEL_CTX_SWITCH */

	unblock_all_signals();
	return 0;
}