drivers/staging/vboxvideo/vbox_fb.c - linux/kernel/git/bpf/bpf - Git at Google

 /*
  * Copyright (C) 2013-2017 Oracle Corporation
  * This file is based on ast_fb.c
  * Copyright 2012 Red Hat Inc.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sub license, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  *
  * Authors: Dave Airlie <airlied@redhat.com>
  *          Michael Thayer <michael.thayer@oracle.com,
  */
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/mm.h>
 #include <linux/tty.h>
 #include <linux/sysrq.h>
 #include <linux/delay.h>
 #include <linux/fb.h>
 #include <linux/init.h>

 #include <drm/drmP.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_crtc_helper.h>

 #include "vbox_drv.h"
 #include "vboxvideo.h"

 #define VBOX_DIRTY_DELAY (HZ / 30)
 /**
  * Tell the host about dirty rectangles to update.
  */
 static void vbox_dirty_update(struct vbox_fbdev *fbdev,
 			      int x, int y, int width, int height)
 {
 	struct drm_gem_object *obj;
 	struct vbox_bo *bo;
 	int ret = -EBUSY;
 	bool store_for_later = false;
 	int x2, y2;
 	unsigned long flags;
 	struct drm_clip_rect rect;

 	obj = fbdev->afb.obj;
 	bo = gem_to_vbox_bo(obj);

 	/*
 	 * try and reserve the BO, if we fail with busy
 	 * then the BO is being moved and we should
 	 * store up the damage until later.
 	 */
 	if (drm_can_sleep())
 		ret = vbox_bo_reserve(bo, true);
 	if (ret) {
 		if (ret != -EBUSY)
 			return;

 		store_for_later = true;
 	}

 	x2 = x + width - 1;
 	y2 = y + height - 1;
 	spin_lock_irqsave(&fbdev->dirty_lock, flags);

 	if (fbdev->y1 < y)
 		y = fbdev->y1;
 	if (fbdev->y2 > y2)
 		y2 = fbdev->y2;
 	if (fbdev->x1 < x)
 		x = fbdev->x1;
 	if (fbdev->x2 > x2)
 		x2 = fbdev->x2;

 	if (store_for_later) {
 		fbdev->x1 = x;
 		fbdev->x2 = x2;
 		fbdev->y1 = y;
 		fbdev->y2 = y2;
 		spin_unlock_irqrestore(&fbdev->dirty_lock, flags);
 		return;
 	}

 	fbdev->x1 = INT_MAX;
 	fbdev->y1 = INT_MAX;
 	fbdev->x2 = 0;
 	fbdev->y2 = 0;

 	spin_unlock_irqrestore(&fbdev->dirty_lock, flags);

 	/*
 	 * Not sure why the original code subtracted 1 here, but I will keep
 	 * it that way to avoid unnecessary differences.
 	 */
 	rect.x1 = x;
 	rect.x2 = x2 + 1;
 	rect.y1 = y;
 	rect.y2 = y2 + 1;
 	vbox_framebuffer_dirty_rectangles(&fbdev->afb.base, &rect, 1);

 	vbox_bo_unreserve(bo);
 }

 #ifdef CONFIG_FB_DEFERRED_IO
 static void vbox_deferred_io(struct fb_info *info, struct list_head *pagelist)
 {
 	struct vbox_fbdev *fbdev = info->par;
 	unsigned long start, end, min, max;
 	struct page *page;
 	int y1, y2;

 	min = ULONG_MAX;
 	max = 0;
 	list_for_each_entry(page, pagelist, lru) {
 		start = page->index << PAGE_SHIFT;
 		end = start + PAGE_SIZE - 1;
 		min = min(min, start);
 		max = max(max, end);
 	}

 	if (min < max) {
 		y1 = min / info->fix.line_length;
 		y2 = (max / info->fix.line_length) + 1;
 		DRM_INFO("%s: Calling dirty update: 0, %d, %d, %d\n",
 			 __func__, y1, info->var.xres, y2 - y1 - 1);
 		vbox_dirty_update(fbdev, 0, y1, info->var.xres, y2 - y1 - 1);
 	}
 }

 static struct fb_deferred_io vbox_defio = {
 	.delay = VBOX_DIRTY_DELAY,
 	.deferred_io = vbox_deferred_io,
 };
 #endif

 static void vbox_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
 {
 	struct vbox_fbdev *fbdev = info->par;

 	sys_fillrect(info, rect);
 	vbox_dirty_update(fbdev, rect->dx, rect->dy, rect->width, rect->height);
 }

 static void vbox_copyarea(struct fb_info *info, const struct fb_copyarea *area)
 {
 	struct vbox_fbdev *fbdev = info->par;

 	sys_copyarea(info, area);
 	vbox_dirty_update(fbdev, area->dx, area->dy, area->width, area->height);
 }

 static void vbox_imageblit(struct fb_info *info, const struct fb_image *image)
 {
 	struct vbox_fbdev *fbdev = info->par;

 	sys_imageblit(info, image);
 	vbox_dirty_update(fbdev, image->dx, image->dy, image->width,
 			  image->height);
 }

 static struct fb_ops vboxfb_ops = {
 	.owner = THIS_MODULE,
 	.fb_check_var = drm_fb_helper_check_var,
 	.fb_set_par = drm_fb_helper_set_par,
 	.fb_fillrect = vbox_fillrect,
 	.fb_copyarea = vbox_copyarea,
 	.fb_imageblit = vbox_imageblit,
 	.fb_pan_display = drm_fb_helper_pan_display,
 	.fb_blank = drm_fb_helper_blank,
 	.fb_setcmap = drm_fb_helper_setcmap,
 	.fb_debug_enter = drm_fb_helper_debug_enter,
 	.fb_debug_leave = drm_fb_helper_debug_leave,
 };

 static int vboxfb_create_object(struct vbox_fbdev *fbdev,
 				struct DRM_MODE_FB_CMD *mode_cmd,
 				struct drm_gem_object **gobj_p)
 {
 	struct drm_device *dev = fbdev->helper.dev;
 	u32 size;
 	struct drm_gem_object *gobj;
 	u32 pitch = mode_cmd->pitches[0];
 	int ret;

 	size = pitch * mode_cmd->height;
 	ret = vbox_gem_create(dev, size, true, &gobj);
 	if (ret)
 		return ret;

 	*gobj_p = gobj;

 	return 0;
 }

 static int vboxfb_create(struct drm_fb_helper *helper,
 			 struct drm_fb_helper_surface_size *sizes)
 {
 	struct vbox_fbdev *fbdev =
 	    container_of(helper, struct vbox_fbdev, helper);
 	struct drm_device *dev = fbdev->helper.dev;
 	struct DRM_MODE_FB_CMD mode_cmd;
 	struct drm_framebuffer *fb;
 	struct fb_info *info;
 	struct device *device = &dev->pdev->dev;
 	struct drm_gem_object *gobj;
 	struct vbox_bo *bo;
 	int size, ret;
 	u32 pitch;

 	mode_cmd.width = sizes->surface_width;
 	mode_cmd.height = sizes->surface_height;
 	pitch = mode_cmd.width * ((sizes->surface_bpp + 7) / 8);
 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 							  sizes->surface_depth);
 	mode_cmd.pitches[0] = pitch;

 	size = pitch * mode_cmd.height;

 	ret = vboxfb_create_object(fbdev, &mode_cmd, &gobj);
 	if (ret) {
 		DRM_ERROR("failed to create fbcon backing object %d\n", ret);
 		return ret;
 	}

 	ret = vbox_framebuffer_init(dev, &fbdev->afb, &mode_cmd, gobj);
 	if (ret)
 		return ret;

 	bo = gem_to_vbox_bo(gobj);

 	ret = vbox_bo_reserve(bo, false);
 	if (ret)
 		return ret;

 	ret = vbox_bo_pin(bo, TTM_PL_FLAG_VRAM, NULL);
 	if (ret) {
 		vbox_bo_unreserve(bo);
 		return ret;
 	}

 	ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
 	vbox_bo_unreserve(bo);
 	if (ret) {
 		DRM_ERROR("failed to kmap fbcon\n");
 		return ret;
 	}

 	info = framebuffer_alloc(0, device);
 	if (!info)
 		return -ENOMEM;
 	info->par = fbdev;

 	fbdev->size = size;

 	fb = &fbdev->afb.base;
 	fbdev->helper.fb = fb;
 	fbdev->helper.fbdev = info;

 	strcpy(info->fix.id, "vboxdrmfb");

 	/*
 	 * The last flag forces a mode set on VT switches even if the kernel
 	 * does not think it is needed.
 	 */
 	info->flags = FBINFO_DEFAULT | FBINFO_CAN_FORCE_OUTPUT |
 		      FBINFO_MISC_ALWAYS_SETPAR;
 	info->fbops = &vboxfb_ops;

 	ret = fb_alloc_cmap(&info->cmap, 256, 0);
 	if (ret)
 		return -ENOMEM;

 	/*
 	 * This seems to be done for safety checking that the framebuffer
 	 * is not registered twice by different drivers.
 	 */
 	info->apertures = alloc_apertures(1);
 	if (!info->apertures)
 		return -ENOMEM;
 	info->apertures->ranges[0].base = pci_resource_start(dev->pdev, 0);
 	info->apertures->ranges[0].size = pci_resource_len(dev->pdev, 0);

 	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format->depth);
 	drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
 			       sizes->fb_height);

 	info->screen_base = bo->kmap.virtual;
 	info->screen_size = size;

 #ifdef CONFIG_FB_DEFERRED_IO
 	info->fbdefio = &vbox_defio;
 	fb_deferred_io_init(info);
 #endif

 	info->pixmap.flags = FB_PIXMAP_SYSTEM;

 	DRM_DEBUG_KMS("allocated %dx%d\n", fb->width, fb->height);

 	return 0;
 }

 static void vbox_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
 			      u16 blue, int regno)
 {
 }

 static void vbox_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
 			      u16 *blue, int regno)
 {
 	*red = regno;
 	*green = regno;
 	*blue = regno;
 }

 static struct drm_fb_helper_funcs vbox_fb_helper_funcs = {
 	.gamma_set = vbox_fb_gamma_set,
 	.gamma_get = vbox_fb_gamma_get,
 	.fb_probe = vboxfb_create,
 };

 void vbox_fbdev_fini(struct drm_device *dev)
 {
 	struct vbox_private *vbox = dev->dev_private;
 	struct vbox_fbdev *fbdev = vbox->fbdev;
 	struct vbox_framebuffer *afb = &fbdev->afb;

 	drm_fb_helper_unregister_fbi(&fbdev->helper);

 	if (afb->obj) {
 		struct vbox_bo *bo = gem_to_vbox_bo(afb->obj);

 		if (!vbox_bo_reserve(bo, false)) {
 			if (bo->kmap.virtual)
 				ttm_bo_kunmap(&bo->kmap);
 			/*
 			 * QXL does this, but is it really needed before
 			 * freeing?
 			 */
 			if (bo->pin_count)
 				vbox_bo_unpin(bo);
 			vbox_bo_unreserve(bo);
 		}
 		drm_gem_object_unreference_unlocked(afb->obj);
 		afb->obj = NULL;
 	}
 	drm_fb_helper_fini(&fbdev->helper);

 	drm_framebuffer_unregister_private(&afb->base);
 	drm_framebuffer_cleanup(&afb->base);
 }

 int vbox_fbdev_init(struct drm_device *dev)
 {
 	struct vbox_private *vbox = dev->dev_private;
 	struct vbox_fbdev *fbdev;
 	int ret;

 	fbdev = devm_kzalloc(dev->dev, sizeof(*fbdev), GFP_KERNEL);
 	if (!fbdev)
 		return -ENOMEM;

 	vbox->fbdev = fbdev;
 	spin_lock_init(&fbdev->dirty_lock);

 	drm_fb_helper_prepare(dev, &fbdev->helper, &vbox_fb_helper_funcs);
 	ret = drm_fb_helper_init(dev, &fbdev->helper, vbox->num_crtcs);
 	if (ret)
 		return ret;

 	ret = drm_fb_helper_single_add_all_connectors(&fbdev->helper);
 	if (ret)
 		goto err_fini;

 	/* disable all the possible outputs/crtcs before entering KMS mode */
 	drm_helper_disable_unused_functions(dev);

 	ret = drm_fb_helper_initial_config(&fbdev->helper, 32);
 	if (ret)
 		goto err_fini;

 	return 0;

 err_fini:
 	drm_fb_helper_fini(&fbdev->helper);
 	return ret;
 }

 void vbox_fbdev_set_base(struct vbox_private *vbox, unsigned long gpu_addr)
 {
 	struct fb_info *fbdev = vbox->fbdev->helper.fbdev;

 	fbdev->fix.smem_start = fbdev->apertures->ranges[0].base + gpu_addr;
 	fbdev->fix.smem_len = vbox->available_vram_size - gpu_addr;
 }
	/*
	* Copyright (C) 2013-2017 Oracle Corporation
	* This file is based on ast_fb.c
	* Copyright 2012 Red Hat Inc.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sub license, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial portions
	* of the Software.
	*
	* Authors: Dave Airlie <airlied@redhat.com>
	* Michael Thayer <michael.thayer@oracle.com,
	*/
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/string.h>
	#include <linux/mm.h>
	#include <linux/tty.h>
	#include <linux/sysrq.h>
	#include <linux/delay.h>
	#include <linux/fb.h>
	#include <linux/init.h>

	#include <drm/drmP.h>
	#include <drm/drm_crtc.h>
	#include <drm/drm_fb_helper.h>
	#include <drm/drm_crtc_helper.h>

	#include "vbox_drv.h"
	#include "vboxvideo.h"

	#define VBOX_DIRTY_DELAY (HZ / 30)
	/**
	* Tell the host about dirty rectangles to update.
	*/
	static void vbox_dirty_update(struct vbox_fbdev *fbdev,
	int x, int y, int width, int height)
	{
	struct drm_gem_object *obj;
	struct vbox_bo *bo;
	int ret = -EBUSY;
	bool store_for_later = false;
	int x2, y2;
	unsigned long flags;
	struct drm_clip_rect rect;

	obj = fbdev->afb.obj;
	bo = gem_to_vbox_bo(obj);

	/*
	* try and reserve the BO, if we fail with busy
	* then the BO is being moved and we should
	* store up the damage until later.
	*/
	if (drm_can_sleep())
	ret = vbox_bo_reserve(bo, true);
	if (ret) {
	if (ret != -EBUSY)
	return;

	store_for_later = true;
	}

	x2 = x + width - 1;
	y2 = y + height - 1;
	spin_lock_irqsave(&fbdev->dirty_lock, flags);

	if (fbdev->y1 < y)
	y = fbdev->y1;
	if (fbdev->y2 > y2)
	y2 = fbdev->y2;
	if (fbdev->x1 < x)
	x = fbdev->x1;
	if (fbdev->x2 > x2)
	x2 = fbdev->x2;

	if (store_for_later) {
	fbdev->x1 = x;
	fbdev->x2 = x2;
	fbdev->y1 = y;
	fbdev->y2 = y2;
	spin_unlock_irqrestore(&fbdev->dirty_lock, flags);
	return;
	}

	fbdev->x1 = INT_MAX;
	fbdev->y1 = INT_MAX;
	fbdev->x2 = 0;
	fbdev->y2 = 0;

	spin_unlock_irqrestore(&fbdev->dirty_lock, flags);

	/*
	* Not sure why the original code subtracted 1 here, but I will keep
	* it that way to avoid unnecessary differences.
	*/
	rect.x1 = x;
	rect.x2 = x2 + 1;
	rect.y1 = y;
	rect.y2 = y2 + 1;
	vbox_framebuffer_dirty_rectangles(&fbdev->afb.base, &rect, 1);

	vbox_bo_unreserve(bo);
	}

	#ifdef CONFIG_FB_DEFERRED_IO
	static void vbox_deferred_io(struct fb_info info, struct list_head pagelist)
	{
	struct vbox_fbdev *fbdev = info->par;
	unsigned long start, end, min, max;
	struct page *page;
	int y1, y2;

	min = ULONG_MAX;
	max = 0;
	list_for_each_entry(page, pagelist, lru) {
	start = page->index << PAGE_SHIFT;
	end = start + PAGE_SIZE - 1;
	min = min(min, start);
	max = max(max, end);
	}

	if (min < max) {
	y1 = min / info->fix.line_length;
	y2 = (max / info->fix.line_length) + 1;
	DRM_INFO("%s: Calling dirty update: 0, %d, %d, %d\n",
	__func__, y1, info->var.xres, y2 - y1 - 1);
	vbox_dirty_update(fbdev, 0, y1, info->var.xres, y2 - y1 - 1);
	}
	}

	static struct fb_deferred_io vbox_defio = {
	.delay = VBOX_DIRTY_DELAY,
	.deferred_io = vbox_deferred_io,
	};
	#endif

	static void vbox_fillrect(struct fb_info info, const struct fb_fillrect rect)
	{
	struct vbox_fbdev *fbdev = info->par;

	sys_fillrect(info, rect);
	vbox_dirty_update(fbdev, rect->dx, rect->dy, rect->width, rect->height);
	}

	static void vbox_copyarea(struct fb_info info, const struct fb_copyarea area)
	{
	struct vbox_fbdev *fbdev = info->par;

	sys_copyarea(info, area);
	vbox_dirty_update(fbdev, area->dx, area->dy, area->width, area->height);
	}

	static void vbox_imageblit(struct fb_info info, const struct fb_image image)
	{
	struct vbox_fbdev *fbdev = info->par;

	sys_imageblit(info, image);
	vbox_dirty_update(fbdev, image->dx, image->dy, image->width,
	image->height);
	}

	static struct fb_ops vboxfb_ops = {
	.owner = THIS_MODULE,
	.fb_check_var = drm_fb_helper_check_var,
	.fb_set_par = drm_fb_helper_set_par,
	.fb_fillrect = vbox_fillrect,
	.fb_copyarea = vbox_copyarea,
	.fb_imageblit = vbox_imageblit,
	.fb_pan_display = drm_fb_helper_pan_display,
	.fb_blank = drm_fb_helper_blank,
	.fb_setcmap = drm_fb_helper_setcmap,
	.fb_debug_enter = drm_fb_helper_debug_enter,
	.fb_debug_leave = drm_fb_helper_debug_leave,
	};

	static int vboxfb_create_object(struct vbox_fbdev *fbdev,
	struct DRM_MODE_FB_CMD *mode_cmd,
	struct drm_gem_object **gobj_p)
	{
	struct drm_device *dev = fbdev->helper.dev;
	u32 size;
	struct drm_gem_object *gobj;
	u32 pitch = mode_cmd->pitches[0];
	int ret;

	size = pitch * mode_cmd->height;
	ret = vbox_gem_create(dev, size, true, &gobj);
	if (ret)
	return ret;

	*gobj_p = gobj;

	return 0;
	}

	static int vboxfb_create(struct drm_fb_helper *helper,
	struct drm_fb_helper_surface_size *sizes)
	{
	struct vbox_fbdev *fbdev =
	container_of(helper, struct vbox_fbdev, helper);
	struct drm_device *dev = fbdev->helper.dev;
	struct DRM_MODE_FB_CMD mode_cmd;
	struct drm_framebuffer *fb;
	struct fb_info *info;
	struct device *device = &dev->pdev->dev;
	struct drm_gem_object *gobj;
	struct vbox_bo *bo;
	int size, ret;
	u32 pitch;

	mode_cmd.width = sizes->surface_width;
	mode_cmd.height = sizes->surface_height;
	pitch = mode_cmd.width * ((sizes->surface_bpp + 7) / 8);
	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
	sizes->surface_depth);
	mode_cmd.pitches[0] = pitch;

	size = pitch * mode_cmd.height;

	ret = vboxfb_create_object(fbdev, &mode_cmd, &gobj);
	if (ret) {
	DRM_ERROR("failed to create fbcon backing object %d\n", ret);
	return ret;
	}

	ret = vbox_framebuffer_init(dev, &fbdev->afb, &mode_cmd, gobj);
	if (ret)
	return ret;

	bo = gem_to_vbox_bo(gobj);

	ret = vbox_bo_reserve(bo, false);
	if (ret)
	return ret;

	ret = vbox_bo_pin(bo, TTM_PL_FLAG_VRAM, NULL);
	if (ret) {
	vbox_bo_unreserve(bo);
	return ret;
	}

	ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
	vbox_bo_unreserve(bo);
	if (ret) {
	DRM_ERROR("failed to kmap fbcon\n");
	return ret;
	}

	info = framebuffer_alloc(0, device);
	if (!info)
	return -ENOMEM;
	info->par = fbdev;

	fbdev->size = size;

	fb = &fbdev->afb.base;
	fbdev->helper.fb = fb;
	fbdev->helper.fbdev = info;

	strcpy(info->fix.id, "vboxdrmfb");

	/*
	* The last flag forces a mode set on VT switches even if the kernel
	* does not think it is needed.
	*/
	info->flags = FBINFO_DEFAULT \| FBINFO_CAN_FORCE_OUTPUT \|
	FBINFO_MISC_ALWAYS_SETPAR;
	info->fbops = &vboxfb_ops;

	ret = fb_alloc_cmap(&info->cmap, 256, 0);
	if (ret)
	return -ENOMEM;

	/*
	* This seems to be done for safety checking that the framebuffer
	* is not registered twice by different drivers.
	*/
	info->apertures = alloc_apertures(1);
	if (!info->apertures)
	return -ENOMEM;
	info->apertures->ranges[0].base = pci_resource_start(dev->pdev, 0);
	info->apertures->ranges[0].size = pci_resource_len(dev->pdev, 0);

	drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format->depth);
	drm_fb_helper_fill_var(info, &fbdev->helper, sizes->fb_width,
	sizes->fb_height);

	info->screen_base = bo->kmap.virtual;
	info->screen_size = size;

	#ifdef CONFIG_FB_DEFERRED_IO
	info->fbdefio = &vbox_defio;
	fb_deferred_io_init(info);
	#endif

	info->pixmap.flags = FB_PIXMAP_SYSTEM;

	DRM_DEBUG_KMS("allocated %dx%d\n", fb->width, fb->height);

	return 0;
	}

	static void vbox_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
	u16 blue, int regno)
	{
	}

	static void vbox_fb_gamma_get(struct drm_crtc crtc, u16 red, u16 *green,
	u16 *blue, int regno)
	{
	*red = regno;
	*green = regno;
	*blue = regno;
	}

	static struct drm_fb_helper_funcs vbox_fb_helper_funcs = {
	.gamma_set = vbox_fb_gamma_set,
	.gamma_get = vbox_fb_gamma_get,
	.fb_probe = vboxfb_create,
	};

	void vbox_fbdev_fini(struct drm_device *dev)
	{
	struct vbox_private *vbox = dev->dev_private;
	struct vbox_fbdev *fbdev = vbox->fbdev;
	struct vbox_framebuffer *afb = &fbdev->afb;

	drm_fb_helper_unregister_fbi(&fbdev->helper);

	if (afb->obj) {
	struct vbox_bo *bo = gem_to_vbox_bo(afb->obj);

	if (!vbox_bo_reserve(bo, false)) {
	if (bo->kmap.virtual)
	ttm_bo_kunmap(&bo->kmap);
	/*
	* QXL does this, but is it really needed before
	* freeing?
	*/
	if (bo->pin_count)
	vbox_bo_unpin(bo);
	vbox_bo_unreserve(bo);
	}
	drm_gem_object_unreference_unlocked(afb->obj);
	afb->obj = NULL;
	}
	drm_fb_helper_fini(&fbdev->helper);

	drm_framebuffer_unregister_private(&afb->base);
	drm_framebuffer_cleanup(&afb->base);
	}

	int vbox_fbdev_init(struct drm_device *dev)
	{
	struct vbox_private *vbox = dev->dev_private;
	struct vbox_fbdev *fbdev;
	int ret;

	fbdev = devm_kzalloc(dev->dev, sizeof(*fbdev), GFP_KERNEL);
	if (!fbdev)
	return -ENOMEM;

	vbox->fbdev = fbdev;
	spin_lock_init(&fbdev->dirty_lock);

	drm_fb_helper_prepare(dev, &fbdev->helper, &vbox_fb_helper_funcs);
	ret = drm_fb_helper_init(dev, &fbdev->helper, vbox->num_crtcs);
	if (ret)
	return ret;

	ret = drm_fb_helper_single_add_all_connectors(&fbdev->helper);
	if (ret)
	goto err_fini;

	/* disable all the possible outputs/crtcs before entering KMS mode */
	drm_helper_disable_unused_functions(dev);

	ret = drm_fb_helper_initial_config(&fbdev->helper, 32);
	if (ret)
	goto err_fini;

	return 0;

	err_fini:
	drm_fb_helper_fini(&fbdev->helper);
	return ret;
	}

	void vbox_fbdev_set_base(struct vbox_private *vbox, unsigned long gpu_addr)
	{
	struct fb_info *fbdev = vbox->fbdev->helper.fbdev;

	fbdev->fix.smem_start = fbdev->apertures->ranges[0].base + gpu_addr;
	fbdev->fix.smem_len = vbox->available_vram_size - gpu_addr;
	}