Front buffer kludge

This makes the GEM "info" ioctl produce an object handle which can be used to refer
to the front buffer (i.e. screen pixmap) in Xorg or otherwise.  This is unfortunately
necessary since this memory is allocated in the kernel by the framebuffer driver, and
is not available to DRM until we move to KMS.

Signed-off-by: Thomas White <taw@bitwiz.org.uk>

1 files changed, 22 insertions, 12 deletions

diff --git a/drivers/mfd/glamo/glamo-cmdq.c b/drivers/mfd/glamo/glamo-cmdq.c
index 32fad98be8a..3c410f828da 100644
--- a/drivers/mfd/glamo/glamo-cmdq.c
+++ b/drivers/mfd/glamo/glamo-cmdq.c
@@ -243,6 +243,7 @@ static int glamo_do_relocation(struct glamodrm_handle *gdrm,
 			       struct drm_file *file_priv)
 {
 	u32 *handles;
+	u32 front_handle;
 	int *offsets;
 	int nobjs =  cbuf->nobjs;
 	int i;
@@ -259,6 +260,8 @@ static int glamo_do_relocation(struct glamodrm_handle *gdrm,
 	if ( copy_from_user(offsets, cbuf->obj_pos, nobjs*sizeof(int)) )
 		return -1;
 
+	front_handle = gdrm->front_buffer_handle;
+
 	for ( i=0; i<nobjs; i++ ) {
 
 		u32 handle = handles[i];
@@ -277,22 +280,29 @@ static int glamo_do_relocation(struct glamodrm_handle *gdrm,
 			goto fail;
 		}
 
-		obj = drm_gem_object_lookup(dev, file_priv, handle);
-		if ( obj == NULL ) return -1;
+		if ( handle == front_handle ) {
 
-		/* Unref the object now, or it'll never get freed.
-		 * This should really happen after the GPU has finished
-		 * the commands which are about to be submitted. */
-		drm_gem_object_unreference(obj);
+			addr = GLAMO_OFFSET_FRAMEBUFFER;
 
-		gobj = obj->driver_private;
-		if ( gobj == NULL ) {
-			printk(KERN_WARNING "[glamo-drm] This object has no "
-					    "private data!\n");
-			goto fail;
+		} else {
+			obj = drm_gem_object_lookup(dev, file_priv, handle);
+			if ( obj == NULL ) return -1;
+
+			/* Unref the object now, or it'll never get freed.
+			 * This should really happen after the GPU has finished
+			 * the commands which are about to be submitted. */
+			drm_gem_object_unreference(obj);
+
+			gobj = obj->driver_private;
+			if ( gobj == NULL ) {
+				printk(KERN_WARNING "[glamo-drm] This object "
+				                    "has no private data!\n");
+				goto fail;
+			}
+
+			addr = GLAMO_OFFSET_WORK + gobj->block->start;
 		}
 
-		addr = GLAMO_OFFSET_WORK + gobj->block->start;
 		addr_low = addr & 0xffff;
 		addr_high = (addr >> 16) & 0x7f;
 		printk(KERN_INFO "Addr low 0x%x, high 0x%x\n",