Index: uspace/srv/fb/fb.c
===================================================================
--- uspace/srv/fb/fb.c	(revision 2d320816b2f2fe3ea0819c573ee3e5a20663b17a)
+++ uspace/srv/fb/fb.c	(revision a728ed387e8ca7c69004595c8b54f9e5ae92a43b)
@@ -272,5 +272,5 @@
 
 
-/** Clear viewport
+/** Clear viewport.
  *
  * @param vport Viewport to clear
@@ -283,5 +283,5 @@
 }
 
-/** Scroll viewport by given number of lines
+/** Scroll viewport by the specified number of lines.
  *
  * @param vport Viewport to scroll
@@ -291,22 +291,54 @@
 static void vport_scroll(viewport_t *vport, int lines)
 {
-	unsigned int row, col;
+	/*
+	 * Scroll backbuffer.
+	 */
 
 	if (lines > 0) {
-		memcpy(vport->backbuf, vport->backbuf + vport->cols * lines,
+		memmove(vport->backbuf, vport->backbuf + vport->cols * lines,
 		    vport->cols * (vport->rows - lines));
 		memset(&vport->backbuf[BB_POS(vport, 0, vport->rows - lines)],
 		    0, vport->cols * lines);
 	} else {
-		memcpy(vport->backbuf - vport->cols * lines, vport->backbuf,
+		memmove(vport->backbuf - vport->cols * lines, vport->backbuf,
 		    vport->cols * (vport->rows + lines));
 		memset(vport->backbuf, 0, - vport->cols * lines);
 	}
 
-	for (row = 0; row < vport->rows; row++) {
-		for (col = 0; col < vport->cols; col++) {
-			draw_glyph(vport, false, col, row);
-		}
-	}
+	/* 
+	 * Scroll pixels.
+	 */
+
+	unsigned int dist, height, alines;
+	unsigned int y, ry;
+	uint8_t *sp, *dp;
+
+	alines = lines > 0 ? lines : -lines;
+	dist = alines * FONT_SCANLINES;
+	height = (vport->rows - alines) * FONT_SCANLINES;
+
+	if (lines > 0) {
+		dp = &screen.fb_addr[FB_POS(vport->x, vport->y + 0)];
+		sp = &screen.fb_addr[FB_POS(vport->x, vport->y + dist)];
+		ry = height;
+	} else {
+		dp = &screen.fb_addr[FB_POS(vport->x, vport->y + dist)];
+		sp = &screen.fb_addr[FB_POS(vport->x, vport->y + 0)];
+		ry = 0;
+	}
+
+	/* Move pixels line by line. */
+	for (y = 0; y < height; y++) {
+		memcpy(dp, sp, vport->cols * FONT_WIDTH
+		    * screen.pixelbytes);
+
+		sp += screen.scanline;
+		dp += screen.scanline;
+	}
+
+	/* Fill emptied area with background color. */
+	draw_filled_rect(vport->x, vport->y + ry,
+	    vport->x + COL2X(vport->cols), vport->y + ry + dist,
+	    vport->style.bg_color);
 }