Refactor common, boilerplate ioctl code from drm_addbufs_* functions into

drm_addbufs. This makes the code more like the BSD code, and makes the
drm_addbufs_* functions callable in-kernel.

From: Ian Romanick <idr@us.ibm.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/drm_bufs.c

@@ -362,25 +362,19 @@ static void drm_cleanup_buf_error(drm_device_t *dev, drm_buf_entry_t *entry)
 
 #if __OS_HAS_AGP
 /**
- * Add AGP buffers for DMA transfers (ioctl).
+ * Add AGP buffers for DMA transfers.
  *
- * \param inode device inode.
- * \param filp file pointer.
- * \param cmd command.
- * \param arg pointer to a drm_buf_desc_t request.
+ * \param dev drm_device_t to which the buffers are to be added.
+ * \param request pointer to a drm_buf_desc_t describing the request.
  * \return zero on success or a negative number on failure.
  * 
  * After some sanity checks creates a drm_buf structure for each buffer and
  * reallocates the buffer list of the same size order to accommodate the new
  * buffers.
  */
-static int drm_addbufs_agp( struct inode *inode, struct file *filp,
-			    unsigned int cmd, unsigned long arg )
+static int drm_addbufs_agp(drm_device_t *dev, drm_buf_desc_t *request)
 {
-	drm_file_t *priv = filp->private_data;
-	drm_device_t *dev = priv->head->dev;
 	drm_device_dma_t *dma = dev->dma;
-	drm_buf_desc_t request;
 	drm_buf_entry_t *entry;
 	drm_buf_t *buf;
 	unsigned long offset;
@@ -394,25 +388,20 @@ static int drm_addbufs_agp( struct inode *inode, struct file *filp,
 	int byte_count;
 	int i;
 	drm_buf_t **temp_buflist;
-	drm_buf_desc_t __user *argp = (void __user *)arg;
 
 	if ( !dma ) return -EINVAL;
 
-	if ( copy_from_user( &request, argp,
-			     sizeof(request) ) )
-		return -EFAULT;
-
-	count = request.count;
-	order = drm_order( request.size );
+	count = request->count;
+	order = drm_order(request->size);
 	size = 1 << order;
 
-	alignment  = (request.flags & _DRM_PAGE_ALIGN)
+	alignment  = (request->flags & _DRM_PAGE_ALIGN)
 		? PAGE_ALIGN(size) : size;
 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 	total = PAGE_SIZE << page_order;
 
 	byte_count = 0;
-	agp_offset = dev->agp->base + request.agp_start;
+	agp_offset = dev->agp->base + request->agp_start;
 
 	DRM_DEBUG( "count:      %d\n",  count );
 	DRM_DEBUG( "order:      %d\n",  order );
@@ -526,11 +515,8 @@ static int drm_addbufs_agp( struct inode *inode, struct file *filp,
 
 	up( &dev->struct_sem );
 
-	request.count = entry->buf_count;
-	request.size = size;
-
-	if ( copy_to_user( argp, &request, sizeof(request) ) )
-		return -EFAULT;
+	request->count = entry->buf_count;
+	request->size = size;
 
 	dma->flags = _DRM_DMA_USE_AGP;
 
@@ -539,13 +525,9 @@ static int drm_addbufs_agp( struct inode *inode, struct file *filp,
 }
 #endif /* __OS_HAS_AGP */
 
-static int drm_addbufs_pci( struct inode *inode, struct file *filp,
-			    unsigned int cmd, unsigned long arg )
+static int drm_addbufs_pci(drm_device_t *dev, drm_buf_desc_t *request)
 {
-   	drm_file_t *priv = filp->private_data;
-	drm_device_t *dev = priv->head->dev;
 	drm_device_dma_t *dma = dev->dma;
-	drm_buf_desc_t request;
 	int count;
 	int order;
 	int size;
@@ -561,26 +543,22 @@ static int drm_addbufs_pci( struct inode *inode, struct file *filp,
 	int page_count;
 	unsigned long *temp_pagelist;
 	drm_buf_t **temp_buflist;
-	drm_buf_desc_t __user *argp = (void __user *)arg;
 
 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA)) return -EINVAL;
 	if ( !dma ) return -EINVAL;
 
-	if ( copy_from_user( &request, argp, sizeof(request) ) )
-		return -EFAULT;
-
-	count = request.count;
-	order = drm_order( request.size );
+	count = request->count;
+	order = drm_order(request->size);
 	size = 1 << order;
 
 	DRM_DEBUG( "count=%d, size=%d (%d), order=%d, queue_count=%d\n",
-		   request.count, request.size, size,
+		   request->count, request->size, size,
 		   order, dev->queue_count );
 
 	if ( order < DRM_MIN_ORDER || order > DRM_MAX_ORDER ) return -EINVAL;
 	if ( dev->queue_count ) return -EBUSY; /* Not while in use */
 
-	alignment = (request.flags & _DRM_PAGE_ALIGN)
+	alignment = (request->flags & _DRM_PAGE_ALIGN)
 		? PAGE_ALIGN(size) : size;
 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 	total = PAGE_SIZE << page_order;
@@ -758,25 +736,17 @@ static int drm_addbufs_pci( struct inode *inode, struct file *filp,
 
 	up( &dev->struct_sem );
 
-	request.count = entry->buf_count;
-	request.size = size;
-
-	if ( copy_to_user( argp, &request, sizeof(request) ) )
-		return -EFAULT;
+	request->count = entry->buf_count;
+	request->size = size;
 
 	atomic_dec( &dev->buf_alloc );
 	return 0;
 
 }
 
-static int drm_addbufs_sg( struct inode *inode, struct file *filp,
-			   unsigned int cmd, unsigned long arg )
+static int drm_addbufs_sg(drm_device_t *dev, drm_buf_desc_t *request)
 {
-	drm_file_t *priv = filp->private_data;
-	drm_device_t *dev = priv->head->dev;
 	drm_device_dma_t *dma = dev->dma;
-	drm_buf_desc_t __user *argp = (void __user *)arg;
-	drm_buf_desc_t request;
 	drm_buf_entry_t *entry;
 	drm_buf_t *buf;
 	unsigned long offset;
@@ -795,20 +765,17 @@ static int drm_addbufs_sg( struct inode *inode, struct file *filp,
 	
 	if ( !dma ) return -EINVAL;
 
-	if ( copy_from_user( &request, argp, sizeof(request) ) )
-		return -EFAULT;
-
-	count = request.count;
-	order = drm_order( request.size );
+	count = request->count;
+	order = drm_order(request->size);
 	size = 1 << order;
 
-	alignment  = (request.flags & _DRM_PAGE_ALIGN)
+	alignment  = (request->flags & _DRM_PAGE_ALIGN)
 			? PAGE_ALIGN(size) : size;
 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 	total = PAGE_SIZE << page_order;
 
 	byte_count = 0;
-	agp_offset = request.agp_start;
+	agp_offset = request->agp_start;
 
 	DRM_DEBUG( "count:      %d\n",  count );
 	DRM_DEBUG( "order:      %d\n",  order );
@@ -923,11 +890,8 @@ static int drm_addbufs_sg( struct inode *inode, struct file *filp,
 
 	up( &dev->struct_sem );
 
-	request.count = entry->buf_count;
-	request.size = size;
-
-	if ( copy_to_user( argp, &request, sizeof(request) ) )
-		return -EFAULT;
+	request->count = entry->buf_count;
+	request->size = size;
 
 	dma->flags = _DRM_DMA_USE_SG;
 
@@ -935,13 +899,9 @@ static int drm_addbufs_sg( struct inode *inode, struct file *filp,
 	return 0;
 }
 
-int drm_addbufs_fb(struct inode *inode, struct file *filp,
-		    unsigned int cmd, unsigned long arg)
+int drm_addbufs_fb(drm_device_t *dev, drm_buf_desc_t *request)
 {
-	drm_file_t *priv = filp->private_data;
-	drm_device_t *dev = priv->head->dev;
 	drm_device_dma_t *dma = dev->dma;
-	drm_buf_desc_t request;
 	drm_buf_entry_t *entry;
 	drm_buf_t *buf;
 	unsigned long offset;
@@ -955,7 +915,6 @@ int drm_addbufs_fb(struct inode *inode, struct file *filp,
 	int byte_count;
 	int i;
 	drm_buf_t **temp_buflist;
-	drm_buf_desc_t __user *argp = (void __user *)arg;
 
 	if (!drm_core_check_feature(dev, DRIVER_FB_DMA))
 		return -EINVAL;
@@ -963,20 +922,17 @@ int drm_addbufs_fb(struct inode *inode, struct file *filp,
 	if (!dma)
 		return -EINVAL;
 
-	if (copy_from_user(&request, argp, sizeof(request)))
-		return -EFAULT;
-
-	count = request.count;
-	order = drm_order(request.size);
+	count = request->count;
+	order = drm_order(request->size);
 	size = 1 << order;
 
-	alignment = (request.flags & _DRM_PAGE_ALIGN)
+	alignment = (request->flags & _DRM_PAGE_ALIGN)
 	    ? PAGE_ALIGN(size) : size;
 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
 	total = PAGE_SIZE << page_order;
 
 	byte_count = 0;
-	agp_offset = request.agp_start;
+	agp_offset = request->agp_start;
 
 	DRM_DEBUG("count:      %d\n", count);
 	DRM_DEBUG("order:      %d\n", order);
@@ -1089,11 +1045,8 @@ int drm_addbufs_fb(struct inode *inode, struct file *filp,
 
 	up(&dev->struct_sem);
 
-	request.count = entry->buf_count;
-	request.size = size;
-
-	if (copy_to_user(argp, &request, sizeof(request)))
-		return -EFAULT;
+	request->count = entry->buf_count;
+	request->size = size;
 
 	dma->flags = _DRM_DMA_USE_FB;
 
@@ -1121,6 +1074,7 @@ int drm_addbufs( struct inode *inode, struct file *filp,
 	drm_buf_desc_t request;
 	drm_file_t *priv = filp->private_data;
 	drm_device_t *dev = priv->head->dev;
+	int ret;
 	
 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 		return -EINVAL;
@@ -1131,15 +1085,23 @@ int drm_addbufs( struct inode *inode, struct file *filp,
 
 #if __OS_HAS_AGP
 	if ( request.flags & _DRM_AGP_BUFFER )
-		return drm_addbufs_agp( inode, filp, cmd, arg );
+		ret=drm_addbufs_agp(dev, &request);
 	else
 #endif
 	if ( request.flags & _DRM_SG_BUFFER )
-		return drm_addbufs_sg( inode, filp, cmd, arg );
+		ret=drm_addbufs_sg(dev, &request);
 	else if ( request.flags & _DRM_FB_BUFFER)
-		return drm_addbufs_fb( inode, filp, cmd, arg );
+		ret=drm_addbufs_fb(dev, &request);
 	else
-		return drm_addbufs_pci( inode, filp, cmd, arg );
+		ret=drm_addbufs_pci(dev, &request);
+
+	if (ret==0) {
+		if (copy_to_user((void __user *)arg, &request,
+				 sizeof(request))) {
+			ret = -EFAULT;
+		}
+	}
+	return ret;
 }