drm fixup 2/2 - optimise i8x0 accesses..

[Dave Airlie]

   the patch below optimises the drm code to not do put_user() on memory the
   kernel allocated and then mmap-installed to userspace, but instead makes it
   use the kernel virtual address directly instead.

   From: Arjan van de Ven <arjanv@xxxxxxxxxx>
   Signed-off-by: Dave Airlie <airlied@xxxxxxxx>


diff -Nru a/drivers/char/drm/i810_dma.c b/drivers/char/drm/i810_dma.c
--- a/drivers/char/drm/i810_dma.c	Sat Aug 28 00:01:57 2004
+++ b/drivers/char/drm/i810_dma.c	Sat Aug 28 00:01:57 2004
@@ -844,13 +844,10 @@
 	if (buf_priv->currently_mapped == I810_BUF_MAPPED) {
 		unsigned int prim = (sarea_priv->vertex_prim & PR_MASK);

-		put_user((GFX_OP_PRIMITIVE | prim |
-					     ((used/4)-2)),
-		(u32 __user *)buf_priv->virtual);
+		*(u32 *)buf_priv->kernel_virtual = ((GFX_OP_PRIMITIVE | prim | ((used/4)-2)));

 		if (used & 4) {
-			put_user(0,
-			(u32 __user *)((u32)buf_priv->virtual + used));
+			*(u32 *)((u32)buf_priv->kernel_virtual + used) = 0;
 			used += 4;
 		}

diff -Nru a/drivers/char/drm/i830_dma.c b/drivers/char/drm/i830_dma.c
--- a/drivers/char/drm/i830_dma.c	Sat Aug 28 00:01:57 2004
+++ b/drivers/char/drm/i830_dma.c	Sat Aug 28 00:01:57 2004
@@ -1166,19 +1166,19 @@
    	DRM_DEBUG(  "start + used - 4 : %ld\n", start + used - 4);

 	if (buf_priv->currently_mapped == I830_BUF_MAPPED) {
-		u32  __user *vp = buf_priv->virtual;
+		u32 *vp = buf_priv->kernel_virtual;

-		put_user( (GFX_OP_PRIMITIVE |
-			 sarea_priv->vertex_prim |
-			  ((used/4)-2)), &vp[0]);
+		vp[0] = (GFX_OP_PRIMITIVE |
+			sarea_priv->vertex_prim |
+			((used/4)-2));

 		if (dev_priv->use_mi_batchbuffer_start) {
-			put_user(MI_BATCH_BUFFER_END, &vp[used/4]);
+			vp[used/4] = MI_BATCH_BUFFER_END;
 			used += 4;
 		}

 		if (used & 4) {
-			put_user(0, &vp[used/4]);
+			vp[used/4] = 0;
 			used += 4;
 		}

-
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