fbdev: add drawing functions for framebuffers in system RAM

The generic drawing functions (cfbimgblt, cfbcopyarea, cfbfillrect) assume
that the framebuffer is in IO memory.  However, we have 3 drivers (hecubafb,
arcfb, and vfb) where the framebuffer is allocated from system RAM (via
vmalloc). Using _raw_read/write and family for these drivers (as used in
the cfb* functions) is illegal, especially in other platforms.

Create 3 new drawing functions, based almost entirely from the original
except that the framebuffer memory is assumed to be in system RAM.
These are named as sysimgblt, syscopyarea, and sysfillrect.

Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/Kconfig

@@ -95,6 +95,33 @@ config FB_CFB_IMAGEBLIT
 	  blitting. This is used by drivers that don't provide their own
 	  (accelerated) version.
 
+config FB_SYS_FILLRECT
+	tristate
+	depends on FB
+	default n
+	---help---
+	  Include the sys_fillrect function for generic software rectangle
+	  filling. This is used by drivers that don't provide their own
+	  (accelerated) version and the framebuffer is in system RAM.
+
+config FB_SYS_COPYAREA
+	tristate
+	depends on FB
+	default n
+	---help---
+	  Include the sys_copyarea function for generic software area copying.
+	  This is used by drivers that don't provide their own (accelerated)
+	  version and the framebuffer is in system RAM.
+
+config FB_SYS_IMAGEBLIT
+	tristate
+	depends on FB
+	default n
+	---help---
+	  Include the sys_imageblit function for generic software image
+	  blitting. This is used by drivers that don't provide their own
+	  (accelerated) version and the framebuffer is in system RAM.
+
 config FB_DEFERRED_IO
 	bool
 	depends on FB

drivers/video/Makefile

@@ -18,6 +18,9 @@ obj-y				  += backlight/ display/
 obj-$(CONFIG_FB_CFB_FILLRECT)  += cfbfillrect.o
 obj-$(CONFIG_FB_CFB_COPYAREA)  += cfbcopyarea.o
 obj-$(CONFIG_FB_CFB_IMAGEBLIT) += cfbimgblt.o
+obj-$(CONFIG_FB_SYS_FILLRECT)  += sysfillrect.o
+obj-$(CONFIG_FB_SYS_COPYAREA)  += syscopyarea.o
+obj-$(CONFIG_FB_SYS_IMAGEBLIT) += sysimgblt.o
 obj-$(CONFIG_FB_SVGALIB)       += svgalib.o
 obj-$(CONFIG_FB_MACMODES)      += macmodes.o
 obj-$(CONFIG_FB_DDC)           += fb_ddc.o