switch compat_drm_mapbufs() to drm_ioctl_kernel()

Another horror like addbufs; this one is even uglier.  With that
done, drm_ioc32.c should be sane.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 39 insertions, 29 deletions

diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c
index 93e38d51cdc3..1ee84dd802d4 100644
--- a/drivers/gpu/drm/drm_bufs.c
+++ b/drivers/gpu/drm/drm_bufs.c
@@ -1443,15 +1443,15 @@ int drm_legacy_freebufs(struct drm_device *dev, void *data,
  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
  * drm_mmap_dma().
  */
-int drm_legacy_mapbufs(struct drm_device *dev, void *data,
-		       struct drm_file *file_priv)
+int __drm_legacy_mapbufs(struct drm_device *dev, void *data, int *p,
+			 void __user **v,
+			 int (*f)(void *, int, unsigned long,
+				  struct drm_buf *),
+		         struct drm_file *file_priv)
 {
 	struct drm_device_dma *dma = dev->dma;
 	int retcode = 0;
-	const int zero = 0;
 	unsigned long virtual;
-	unsigned long address;
-	struct drm_buf_map *request = data;
 	int i;
 
 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
@@ -1471,7 +1471,7 @@ int drm_legacy_mapbufs(struct drm_device *dev, void *data,
 	dev->buf_use++;		/* Can't allocate more after this call */
 	spin_unlock(&dev->buf_lock);
 
-	if (request->count >= dma->buf_count) {
+	if (*p >= dma->buf_count) {
 		if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
 		    || (drm_core_check_feature(dev, DRIVER_SG)
 			&& (dma->flags & _DRM_DMA_USE_SG))) {
@@ -1496,41 +1496,51 @@ int drm_legacy_mapbufs(struct drm_device *dev, void *data,
 			retcode = (signed long)virtual;
 			goto done;
 		}
-		request->virtual = (void __user *)virtual;
+		*v = (void __user *)virtual;
 
 		for (i = 0; i < dma->buf_count; i++) {
-			if (copy_to_user(&request->list[i].idx,
-					 &dma->buflist[i]->idx,
-					 sizeof(request->list[0].idx))) {
-				retcode = -EFAULT;
-				goto done;
-			}
-			if (copy_to_user(&request->list[i].total,
-					 &dma->buflist[i]->total,
-					 sizeof(request->list[0].total))) {
-				retcode = -EFAULT;
-				goto done;
-			}
-			if (copy_to_user(&request->list[i].used,
-					 &zero, sizeof(zero))) {
-				retcode = -EFAULT;
-				goto done;
-			}
-			address = virtual + dma->buflist[i]->offset;	/* *** */
-			if (copy_to_user(&request->list[i].address,
-					 &address, sizeof(address))) {
+			if (f(data, i, virtual, dma->buflist[i]) < 0) {
 				retcode = -EFAULT;
 				goto done;
 			}
 		}
 	}
       done:
-	request->count = dma->buf_count;
-	DRM_DEBUG("%d buffers, retcode = %d\n", request->count, retcode);
+	*p = dma->buf_count;
+	DRM_DEBUG("%d buffers, retcode = %d\n", *p, retcode);
 
 	return retcode;
 }
 
+static int map_one_buf(void *data, int idx, unsigned long virtual,
+			struct drm_buf *buf)
+{
+	struct drm_buf_map *request = data;
+	unsigned long address = virtual + buf->offset;	/* *** */
+
+	if (copy_to_user(&request->list[idx].idx, &buf->idx,
+			 sizeof(request->list[0].idx)))
+		return -EFAULT;
+	if (copy_to_user(&request->list[idx].total, &buf->total,
+			 sizeof(request->list[0].total)))
+		return -EFAULT;
+	if (clear_user(&request->list[idx].used, sizeof(int)))
+		return -EFAULT;
+	if (copy_to_user(&request->list[idx].address, &address,
+			 sizeof(address)))
+		return -EFAULT;
+	return 0;
+}
+
+int drm_legacy_mapbufs(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv)
+{
+	struct drm_buf_map *request = data;
+	return __drm_legacy_mapbufs(dev, data, &request->count,
+				    &request->virtual, map_one_buf,
+				    file_priv);
+}
+
 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
 		  struct drm_file *file_priv)
 {