[PATCH 13/19] drm: simplify the locking in the GETCRTC ioctl

[Daniel Vetter]

No need to grab both plane and crtc locks at the same time, we can do
them one after the other. If userspace races it'll get what it
deserves either way.

This removes another user of drm_modeset_lock_crtc. There's only one
left.

Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
 drivers/gpu/drm/drm_crtc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 660b4c8715de..df1ff0b8818b 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -406,16 +406,18 @@ int drm_mode_getcrtc(struct drm_device *dev,
 	if (!crtc)
 		return -ENOENT;
 
-	drm_modeset_lock_crtc(crtc, crtc->primary);
 	crtc_resp->gamma_size = crtc->gamma_size;
 
+	drm_modeset_lock(&crtc->primary->mutex, NULL);
 	if (crtc->primary->state && crtc->primary->state->fb)
 		crtc_resp->fb_id = crtc->primary->state->fb->base.id;
 	else if (!crtc->primary->state && crtc->primary->fb)
 		crtc_resp->fb_id = crtc->primary->fb->base.id;
 	else
 		crtc_resp->fb_id = 0;
+	drm_modeset_unlock(&crtc->primary->mutex);
 
+	drm_modeset_lock(&crtc->mutex, NULL);
 	if (crtc->state) {
 		crtc_resp->x = crtc->primary->state->src_x >> 16;
 		crtc_resp->y = crtc->primary->state->src_y >> 16;
@@ -437,7 +439,7 @@ int drm_mode_getcrtc(struct drm_device *dev,
 			crtc_resp->mode_valid = 0;
 		}
 	}
-	drm_modeset_unlock_crtc(crtc);
+	drm_modeset_unlock(&crtc->mutex);
 
 	return 0;
 }
-- 
2.11.0