diff --git a/drivers/gpu/drm/drm_fbdev_dma.c b/drivers/gpu/drm/drm_fbdev_dma.c
index b14b581c059d..02a516e77192 100644
--- a/drivers/gpu/drm/drm_fbdev_dma.c
+++ b/drivers/gpu/drm/drm_fbdev_dma.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: MIT
 
 #include <linux/fb.h>
+#include <linux/vmalloc.h>
 
 #include <drm/drm_drv.h>
 #include <drm/drm_fbdev_dma.h>
@@ -70,37 +71,102 @@ static const struct fb_ops drm_fbdev_dma_fb_ops = {
 	.fb_destroy = drm_fbdev_dma_fb_destroy,
 };
 
-FB_GEN_DEFAULT_DEFERRED_DMAMEM_OPS(drm_fbdev_dma,
+FB_GEN_DEFAULT_DEFERRED_DMAMEM_OPS(drm_fbdev_dma_shadowed,
 				   drm_fb_helper_damage_range,
 				   drm_fb_helper_damage_area);
 
-static int drm_fbdev_dma_deferred_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+static void drm_fbdev_dma_shadowed_fb_destroy(struct fb_info *info)
 {
 	struct drm_fb_helper *fb_helper = info->par;
-	struct drm_framebuffer *fb = fb_helper->fb;
-	struct drm_gem_dma_object *dma = drm_fb_dma_get_gem_obj(fb, 0);
+	void *shadow = info->screen_buffer;
+
+	if (!fb_helper->dev)
+		return;
 
-	if (!dma->map_noncoherent)
-		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
+	if (info->fbdefio)
+		fb_deferred_io_cleanup(info);
+	drm_fb_helper_fini(fb_helper);
+	vfree(shadow);
 
-	return fb_deferred_io_mmap(info, vma);
+	drm_client_buffer_vunmap(fb_helper->buffer);
+	drm_client_framebuffer_delete(fb_helper->buffer);
+	drm_client_release(&fb_helper->client);
+	drm_fb_helper_unprepare(fb_helper);
+	kfree(fb_helper);
 }
 
-static const struct fb_ops drm_fbdev_dma_deferred_fb_ops = {
+static const struct fb_ops drm_fbdev_dma_shadowed_fb_ops = {
 	.owner = THIS_MODULE,
 	.fb_open = drm_fbdev_dma_fb_open,
 	.fb_release = drm_fbdev_dma_fb_release,
-	__FB_DEFAULT_DEFERRED_OPS_RDWR(drm_fbdev_dma),
+	FB_DEFAULT_DEFERRED_OPS(drm_fbdev_dma_shadowed),
 	DRM_FB_HELPER_DEFAULT_OPS,
-	__FB_DEFAULT_DEFERRED_OPS_DRAW(drm_fbdev_dma),
-	.fb_mmap = drm_fbdev_dma_deferred_fb_mmap,
-	.fb_destroy = drm_fbdev_dma_fb_destroy,
+	.fb_destroy = drm_fbdev_dma_shadowed_fb_destroy,
 };
 
 /*
  * struct drm_fb_helper
  */
 
+static void drm_fbdev_dma_damage_blit_real(struct drm_fb_helper *fb_helper,
+					   struct drm_clip_rect *clip,
+					   struct iosys_map *dst)
+{
+	struct drm_framebuffer *fb = fb_helper->fb;
+	size_t offset = clip->y1 * fb->pitches[0];
+	size_t len = clip->x2 - clip->x1;
+	unsigned int y;
+	void *src;
+
+	switch (drm_format_info_bpp(fb->format, 0)) {
+	case 1:
+		offset += clip->x1 / 8;
+		len = DIV_ROUND_UP(len + clip->x1 % 8, 8);
+		break;
+	case 2:
+		offset += clip->x1 / 4;
+		len = DIV_ROUND_UP(len + clip->x1 % 4, 4);
+		break;
+	case 4:
+		offset += clip->x1 / 2;
+		len = DIV_ROUND_UP(len + clip->x1 % 2, 2);
+		break;
+	default:
+		offset += clip->x1 * fb->format->cpp[0];
+		len *= fb->format->cpp[0];
+		break;
+	}
+
+	src = fb_helper->info->screen_buffer + offset;
+	iosys_map_incr(dst, offset); /* go to first pixel within clip rect */
+
+	for (y = clip->y1; y < clip->y2; y++) {
+		iosys_map_memcpy_to(dst, 0, src, len);
+		iosys_map_incr(dst, fb->pitches[0]);
+		src += fb->pitches[0];
+	}
+}
+
+static int drm_fbdev_dma_damage_blit(struct drm_fb_helper *fb_helper,
+				     struct drm_clip_rect *clip)
+{
+	struct drm_client_buffer *buffer = fb_helper->buffer;
+	struct iosys_map dst;
+
+	/*
+	 * For fbdev emulation, we only have to protect against fbdev modeset
+	 * operations. Nothing else will involve the client buffer's BO. So it
+	 * is sufficient to acquire struct drm_fb_helper.lock here.
+	 */
+	mutex_lock(&fb_helper->lock);
+
+	dst = buffer->map;
+	drm_fbdev_dma_damage_blit_real(fb_helper, clip, &dst);
+
+	mutex_unlock(&fb_helper->lock);
+
+	return 0;
+}
 static int drm_fbdev_dma_helper_fb_dirty(struct drm_fb_helper *helper,
 					 struct drm_clip_rect *clip)
 {
@@ -112,6 +178,10 @@ static int drm_fbdev_dma_helper_fb_dirty(struct drm_fb_helper *helper,
 		return 0;
 
 	if (helper->fb->funcs->dirty) {
+		ret = drm_fbdev_dma_damage_blit(helper, clip);
+		if (drm_WARN_ONCE(dev, ret, "Damage blitter failed: ret=%d\n", ret))
+			return ret;
+
 		ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
 		if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret))
 			return ret;
@@ -128,14 +198,80 @@ static const struct drm_fb_helper_funcs drm_fbdev_dma_helper_funcs = {
  * struct drm_fb_helper
  */
 
+static int drm_fbdev_dma_driver_fbdev_probe_tail(struct drm_fb_helper *fb_helper,
+						 struct drm_fb_helper_surface_size *sizes)
+{
+	struct drm_device *dev = fb_helper->dev;
+	struct drm_client_buffer *buffer = fb_helper->buffer;
+	struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(buffer->gem);
+	struct drm_framebuffer *fb = fb_helper->fb;
+	struct fb_info *info = fb_helper->info;
+	struct iosys_map map = buffer->map;
+
+	info->fbops = &drm_fbdev_dma_fb_ops;
+
+	/* screen */
+	info->flags |= FBINFO_VIRTFB; /* system memory */
+	if (dma_obj->map_noncoherent)
+		info->flags |= FBINFO_READS_FAST; /* signal caching */
+	info->screen_size = sizes->surface_height * fb->pitches[0];
+	info->screen_buffer = map.vaddr;
+	if (!(info->flags & FBINFO_HIDE_SMEM_START)) {
+		if (!drm_WARN_ON(dev, is_vmalloc_addr(info->screen_buffer)))
+			info->fix.smem_start = page_to_phys(virt_to_page(info->screen_buffer));
+	}
+	info->fix.smem_len = info->screen_size;
+
+	return 0;
+}
+
+static int drm_fbdev_dma_driver_fbdev_probe_tail_shadowed(struct drm_fb_helper *fb_helper,
+							  struct drm_fb_helper_surface_size *sizes)
+{
+	struct drm_client_buffer *buffer = fb_helper->buffer;
+	struct fb_info *info = fb_helper->info;
+	size_t screen_size = buffer->gem->size;
+	void *screen_buffer;
+	int ret;
+
+	/*
+	 * Deferred I/O requires struct page for framebuffer memory,
+	 * which is not guaranteed for all DMA ranges. We thus create
+	 * a shadow buffer in system memory.
+	 */
+	screen_buffer = vzalloc(screen_size);
+	if (!screen_buffer)
+		return -ENOMEM;
+
+	info->fbops = &drm_fbdev_dma_shadowed_fb_ops;
+
+	/* screen */
+	info->flags |= FBINFO_VIRTFB; /* system memory */
+	info->flags |= FBINFO_READS_FAST; /* signal caching */
+	info->screen_buffer = screen_buffer;
+	info->fix.smem_len = screen_size;
+
+	fb_helper->fbdefio.delay = HZ / 20;
+	fb_helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
+
+	info->fbdefio = &fb_helper->fbdefio;
+	ret = fb_deferred_io_init(info);
+	if (ret)
+		goto err_vfree;
+
+	return 0;
+
+err_vfree:
+	vfree(screen_buffer);
+	return ret;
+}
+
 int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 				     struct drm_fb_helper_surface_size *sizes)
 {
 	struct drm_client_dev *client = &fb_helper->client;
 	struct drm_device *dev = fb_helper->dev;
-	bool use_deferred_io = false;
 	struct drm_client_buffer *buffer;
-	struct drm_gem_dma_object *dma_obj;
 	struct drm_framebuffer *fb;
 	struct fb_info *info;
 	u32 format;
@@ -152,19 +288,9 @@ int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 					       sizes->surface_height, format);
 	if (IS_ERR(buffer))
 		return PTR_ERR(buffer);
-	dma_obj = to_drm_gem_dma_obj(buffer->gem);
 
 	fb = buffer->fb;
 
-	/*
-	 * Deferred I/O requires struct page for framebuffer memory,
-	 * which is not guaranteed for all DMA ranges. We thus only
-	 * install deferred I/O if we have a framebuffer that requires
-	 * it.
-	 */
-	if (fb->funcs->dirty)
-		use_deferred_io = true;
-
 	ret = drm_client_buffer_vmap(buffer, &map);
 	if (ret) {
 		goto err_drm_client_buffer_delete;
@@ -185,45 +311,12 @@ int drm_fbdev_dma_driver_fbdev_probe(struct drm_fb_helper *fb_helper,
 
 	drm_fb_helper_fill_info(info, fb_helper, sizes);
 
-	if (use_deferred_io)
-		info->fbops = &drm_fbdev_dma_deferred_fb_ops;
+	if (fb->funcs->dirty)
+		ret = drm_fbdev_dma_driver_fbdev_probe_tail_shadowed(fb_helper, sizes);
 	else
-		info->fbops = &drm_fbdev_dma_fb_ops;
-
-	/* screen */
-	info->flags |= FBINFO_VIRTFB; /* system memory */
-	if (dma_obj->map_noncoherent)
-		info->flags |= FBINFO_READS_FAST; /* signal caching */
-	info->screen_size = sizes->surface_height * fb->pitches[0];
-	info->screen_buffer = map.vaddr;
-	if (!(info->flags & FBINFO_HIDE_SMEM_START)) {
-		if (!drm_WARN_ON(dev, is_vmalloc_addr(info->screen_buffer)))
-			info->fix.smem_start = page_to_phys(virt_to_page(info->screen_buffer));
-	}
-	info->fix.smem_len = info->screen_size;
-
-	/*
-	 * Only set up deferred I/O if the screen buffer supports
-	 * it. If this disagrees with the previous test for ->dirty,
-	 * mmap on the /dev/fb file might not work correctly.
-	 */
-	if (!is_vmalloc_addr(info->screen_buffer) && info->fix.smem_start) {
-		unsigned long pfn = info->fix.smem_start >> PAGE_SHIFT;
-
-		if (drm_WARN_ON(dev, !pfn_to_page(pfn)))
-			use_deferred_io = false;
-	}
-
-	/* deferred I/O */
-	if (use_deferred_io) {
-		fb_helper->fbdefio.delay = HZ / 20;
-		fb_helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
-
-		info->fbdefio = &fb_helper->fbdefio;
-		ret = fb_deferred_io_init(info);
-		if (ret)
-			goto err_drm_fb_helper_release_info;
-	}
+		ret = drm_fbdev_dma_driver_fbdev_probe_tail(fb_helper, sizes);
+	if (ret)
+		goto err_drm_fb_helper_release_info;
 
 	return 0;
 
