drm: fix a LOR issue on FreeBSD for savage driver

Correct a LOR issue on FreeBSD by allocating temporary space and doing a single
DRM_COPY_FROM_USER rather than DRM_VERIFYAREA_READ followed by tons of
DRM_COPY_FROM_USER_UNCHECKED.  I don't like the look of the temporary space
allocation, but I like the simplification in the rest of the file.  Tested
with glxgears, tuxracer, and q3 on a savage4.

From: Eric Anholt <anholt@freebsd.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/savage_drv.h

-/* savage_drv.h -- Private header for the savage driver
- *
+/* savage_drv.h -- Private header for the savage driver */
+/*
  * Copyright 2004  Felix Kuehling
  * All Rights Reserved.
  *
@@ -192,7 +192,7 @@ typedef struct drm_savage_private {
 	/* Err, there is a macro wait_event in include/linux/wait.h.
 	 * Avoid unwanted macro expansion. */
 	void (*emit_clip_rect) (struct drm_savage_private * dev_priv,
-				drm_clip_rect_t * pbox);
+				const drm_clip_rect_t * pbox);
 	void (*dma_flush) (struct drm_savage_private * dev_priv);
 } drm_savage_private_t;
 
@@ -217,9 +217,9 @@ extern void savage_reclaim_buffers(drm_device_t * dev, DRMFILE filp);
 
 /* state functions */
 extern void savage_emit_clip_rect_s3d(drm_savage_private_t * dev_priv,
-				      drm_clip_rect_t * pbox);
+				      const drm_clip_rect_t * pbox);
 extern void savage_emit_clip_rect_s4(drm_savage_private_t * dev_priv,
-				     drm_clip_rect_t * pbox);
+				     const drm_clip_rect_t * pbox);
 
 #define SAVAGE_FB_SIZE_S3	0x01000000	/*  16MB */
 #define SAVAGE_FB_SIZE_S4	0x02000000	/*  32MB */
@@ -502,15 +502,6 @@ extern void savage_emit_clip_rect_s4(drm_savage_private_t * dev_priv,
 
 #define BCI_WRITE( val ) *bci_ptr++ = (uint32_t)(val)
 
-#define BCI_COPY_FROM_USER(src,n) do {				\
-    unsigned int i;						\
-    for (i = 0; i < n; ++i) {					\
-	uint32_t val;						\
-	DRM_GET_USER_UNCHECKED(val, &((uint32_t*)(src))[i]);	\
-	BCI_WRITE(val);						\
-    }								\
-} while(0)
-
 /*
  * command DMA support
  */
@@ -536,8 +527,8 @@ extern void savage_emit_clip_rect_s4(drm_savage_private_t * dev_priv,
 
 #define DMA_WRITE( val ) *dma_ptr++ = (uint32_t)(val)
 
-#define DMA_COPY_FROM_USER(src,n) do {				\
-	DRM_COPY_FROM_USER_UNCHECKED(dma_ptr, (src), (n)*4);	\
+#define DMA_COPY(src, n) do {					\
+	memcpy(dma_ptr, (src), (n)*4);				\
 	dma_ptr += n;						\
 } while(0)