4 files changed, 54 insertions, 4 deletions

diff --git a/drivers/gpu/drm/qxl/qxl_cmd.c b/drivers/gpu/drm/qxl/qxl_cmd.c
index 8ec53d5abd62..c0fb52c6d4ca 100644
--- a/drivers/gpu/drm/qxl/qxl_cmd.c
+++ b/drivers/gpu/drm/qxl/qxl_cmd.c
@@ -387,7 +387,11 @@ void qxl_io_create_primary(struct qxl_device *qdev,
         create->width = bo->surf.width;
         create->height = bo->surf.height;
         create->stride = bo->surf.stride;
-        create->mem = qxl_bo_physical_address(qdev, bo, offset);
+        if (bo->shadow) {
+                create->mem = qxl_bo_physical_address(qdev, bo->shadow, offset);
+        } else {
+                create->mem = qxl_bo_physical_address(qdev, bo, offset);
+        }
 
         DRM_DEBUG_DRIVER("mem = %llx, from %p\n", create->mem, bo->kptr);
 
diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index afbf50d0c08f..4756b3c9bf2c 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -305,7 +305,9 @@ static const struct drm_crtc_funcs qxl_crtc_funcs = {
 void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb)
 {
         struct qxl_framebuffer *qxl_fb = to_qxl_framebuffer(fb);
+        struct qxl_bo *bo = gem_to_qxl_bo(qxl_fb->obj);
 
+        WARN_ON(bo->shadow);
         drm_gem_object_unreference_unlocked(qxl_fb->obj);
         drm_framebuffer_cleanup(fb);
         kfree(qxl_fb);
@@ -508,6 +510,7 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
             .x2 = qfb->base.width,
             .y2 = qfb->base.height
         };
+        bool same_shadow = false;
 
         if (old_state->fb) {
                 qfb_old = to_qxl_framebuffer(old_state->fb);
@@ -519,15 +522,23 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
         if (bo == bo_old)
                 return;
 
+        if (bo_old && bo_old->shadow && bo->shadow &&
+            bo_old->shadow == bo->shadow) {
+                same_shadow = true;
+        }
+
         if (bo_old && bo_old->is_primary) {
-                qxl_io_destroy_primary(qdev);
+                if (!same_shadow)
+                        qxl_io_destroy_primary(qdev);
                 bo_old->is_primary = false;
         }
 
         if (!bo->is_primary) {
-                qxl_io_create_primary(qdev, 0, bo);
+                if (!same_shadow)
+                        qxl_io_create_primary(qdev, 0, bo);
                 bo->is_primary = true;
         }
+
         qxl_draw_dirty_fb(qdev, qfb, bo, 0, 0, &norect, 1, 1);
 }
 
@@ -679,8 +690,9 @@ static void qxl_cursor_atomic_disable(struct drm_plane *plane,
 static int qxl_plane_prepare_fb(struct drm_plane *plane,
                                 struct drm_plane_state *new_state)
 {
+        struct qxl_device *qdev = plane->dev->dev_private;
         struct drm_gem_object *obj;
-        struct qxl_bo *user_bo;
+        struct qxl_bo *user_bo, *old_bo = NULL;
         int ret;
 
         if (!new_state->fb)
@@ -689,6 +701,32 @@ static int qxl_plane_prepare_fb(struct drm_plane *plane,
         obj = to_qxl_framebuffer(new_state->fb)->obj;
         user_bo = gem_to_qxl_bo(obj);
 
+        if (plane->type == DRM_PLANE_TYPE_PRIMARY &&
+            user_bo->is_dumb && !user_bo->shadow) {
+                if (plane->state->fb) {
+                        obj = to_qxl_framebuffer(plane->state->fb)->obj;
+                        old_bo = gem_to_qxl_bo(obj);
+                }
+                if (old_bo && old_bo->shadow &&
+                    user_bo->gem_base.size == old_bo->gem_base.size &&
+                    plane->state->crtc     == new_state->crtc &&
+                    plane->state->crtc_w   == new_state->crtc_w &&
+                    plane->state->crtc_h   == new_state->crtc_h &&
+                    plane->state->src_x    == new_state->src_x &&
+                    plane->state->src_y    == new_state->src_y &&
+                    plane->state->src_w    == new_state->src_w &&
+                    plane->state->src_h    == new_state->src_h &&
+                    plane->state->rotation == new_state->rotation &&
+                    plane->state->zpos     == new_state->zpos) {
+                        drm_gem_object_get(&old_bo->shadow->gem_base);
+                        user_bo->shadow = old_bo->shadow;
+                } else {
+                        qxl_bo_create(qdev, user_bo->gem_base.size,
+                                      true, true, QXL_GEM_DOMAIN_VRAM, NULL,
+                                      &user_bo->shadow);
+                }
+        }
+
         ret = qxl_bo_pin(user_bo, QXL_GEM_DOMAIN_CPU, NULL);
         if (ret)
                 return ret;
@@ -713,6 +751,11 @@ static void qxl_plane_cleanup_fb(struct drm_plane *plane,
         obj = to_qxl_framebuffer(old_state->fb)->obj;
         user_bo = gem_to_qxl_bo(obj);
         qxl_bo_unpin(user_bo);
+
+        if (user_bo->shadow && !user_bo->is_primary) {
+                drm_gem_object_put_unlocked(&user_bo->shadow->gem_base);
+                user_bo->shadow = NULL;
+        }
 }
 
 static const uint32_t qxl_cursor_plane_formats[] = {
diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h
index d707b351875c..08752c0ffb35 100644
--- a/drivers/gpu/drm/qxl/qxl_drv.h
+++ b/drivers/gpu/drm/qxl/qxl_drv.h
@@ -89,6 +89,8 @@ struct qxl_bo {
         /* Constant after initialization */
         struct drm_gem_object           gem_base;
         bool is_primary; /* is this now a primary surface */
+        bool is_dumb;
+        struct qxl_bo *shadow;
         bool hw_surf_alloc;
         struct qxl_surface surf;
         uint32_t surface_id;
diff --git a/drivers/gpu/drm/qxl/qxl_dumb.c b/drivers/gpu/drm/qxl/qxl_dumb.c
index 5e65d5d2d937..11085ab01374 100644
--- a/drivers/gpu/drm/qxl/qxl_dumb.c
+++ b/drivers/gpu/drm/qxl/qxl_dumb.c
@@ -63,6 +63,7 @@ int qxl_mode_dumb_create(struct drm_file *file_priv,
                                               &handle);
         if (r)
                 return r;
+        qobj->is_dumb = true;
         args->pitch = pitch;
         args->handle = handle;
         return 0;