[Intel-gfx] [PATCH 1/4] drm: Move page_flip fb lookup earlier

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

No reason that I can see to delay the fb lookup this late. Moving it
earlier allows us to keep it outside of the lock retry loop. This
makes error handling and whatnot simpler.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_plane.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 6153cbda239f..924830071307 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -1009,7 +1009,7 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	struct drm_mode_crtc_page_flip_target *page_flip = data;
 	struct drm_crtc *crtc;
 	struct drm_plane *plane;
-	struct drm_framebuffer *fb = NULL, *old_fb;
+	struct drm_framebuffer *fb, *old_fb;
 	struct drm_pending_vblank_event *e = NULL;
 	u32 target_vblank = page_flip->sequence;
 	struct drm_modeset_acquire_ctx ctx;
@@ -1055,16 +1055,16 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 				DRM_DEBUG("Invalid absolute flip target %u, "
 					  "must be <= %u\n", target_vblank,
 					  current_vblank + 1);
-				drm_crtc_vblank_put(crtc);
-				return -EINVAL;
+				ret = -EINVAL;
+				goto put_vblank;
 			}
 			break;
 		case DRM_MODE_PAGE_FLIP_TARGET_RELATIVE:
 			if (target_vblank != 0 && target_vblank != 1) {
 				DRM_DEBUG("Invalid relative flip target %u, "
 					  "must be 0 or 1\n", target_vblank);
-				drm_crtc_vblank_put(crtc);
-				return -EINVAL;
+				ret = -EINVAL;
+				goto put_vblank;
 			}
 			target_vblank += current_vblank;
 			break;
@@ -1075,7 +1075,14 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 		}
 	} else if (crtc->funcs->page_flip == NULL ||
 		   (page_flip->flags & DRM_MODE_PAGE_FLIP_TARGET)) {
-		return -EINVAL;
+		ret = -EINVAL;
+		goto put_vblank;
+	}
+
+	fb = drm_framebuffer_lookup(dev, file_priv, page_flip->fb_id);
+	if (!fb) {
+		ret = -ENOENT;
+		goto put_vblank;
 	}
 
 	drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
@@ -1101,12 +1108,6 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 		goto out;
 	}
 
-	fb = drm_framebuffer_lookup(dev, file_priv, page_flip->fb_id);
-	if (!fb) {
-		ret = -ENOENT;
-		goto out;
-	}
-
 	if (plane->state) {
 		const struct drm_plane_state *state = plane->state;
 
@@ -1170,8 +1171,6 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	}
 
 out:
-	if (fb)
-		drm_framebuffer_put(fb);
 	if (plane->old_fb)
 		drm_framebuffer_put(plane->old_fb);
 	plane->old_fb = NULL;
@@ -1185,6 +1184,8 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	drm_modeset_drop_locks(&ctx);
 	drm_modeset_acquire_fini(&ctx);
 
+	drm_framebuffer_put(fb);
+put_vblank:
 	if (ret && crtc->funcs->page_flip_target)
 		drm_crtc_vblank_put(crtc);
 
-- 
2.16.4