drm: Remove drm_modeset_legacy_acquire_ctx and crtc->acquire_ctx

With all the callers of drm_modeset_lock_crtc gone, and all the places
it was formerly used properly wiring the acquire ctx through, we can
remove this.

The only hidden context magic we still have is now the global one.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403083304.9083-4-daniel.vetter@ffwll.ch

drivers/gpu/drm/drm_atomic.c

@@ -1516,19 +1516,9 @@ EXPORT_SYMBOL(drm_atomic_add_affected_planes);
 void drm_atomic_legacy_backoff(struct drm_atomic_state *state)
 {
 	struct drm_device *dev = state->dev;
-	unsigned crtc_mask = 0;
-	struct drm_crtc *crtc;
 	int ret;
 	bool global = false;
 
-	drm_for_each_crtc(crtc, dev) {
-		if (crtc->acquire_ctx != state->acquire_ctx)
-			continue;
-
-		crtc_mask |= drm_crtc_mask(crtc);
-		crtc->acquire_ctx = NULL;
-	}
-
 	if (WARN_ON(dev->mode_config.acquire_ctx == state->acquire_ctx)) {
 		global = true;
 
@@ -1542,10 +1532,6 @@ retry:
 	if (ret)
 		goto retry;
 
-	drm_for_each_crtc(crtc, dev)
-		if (drm_crtc_mask(crtc) & crtc_mask)
-			crtc->acquire_ctx = state->acquire_ctx;
-
 	if (global)
 		dev->mode_config.acquire_ctx = state->acquire_ctx;
 }

drivers/gpu/drm/drm_atomic_helper.c

@@ -2975,7 +2975,7 @@ int drm_atomic_helper_connector_dpms(struct drm_connector *connector,
 	if (!state)
 		return -ENOMEM;
 
-	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
+	state->acquire_ctx = crtc->dev->mode_config.acquire_ctx;
 retry:
 	crtc_state = drm_atomic_get_crtc_state(state, crtc);
 	if (IS_ERR(crtc_state)) {

drivers/gpu/drm/drm_modeset_lock.c

@@ -148,27 +148,6 @@ void drm_modeset_unlock_all(struct drm_device *dev)
 }
 EXPORT_SYMBOL(drm_modeset_unlock_all);
 
-/**
- * drm_modeset_legacy_acquire_ctx - find acquire ctx for legacy ioctls
- * @crtc: drm crtc
- *
- * Legacy ioctl operations like cursor updates or page flips only have per-crtc
- * locking, and store the acquire ctx in the corresponding crtc. All other
- * legacy operations take all locks and use a global acquire context. This
- * function grabs the right one.
- */
-struct drm_modeset_acquire_ctx *
-drm_modeset_legacy_acquire_ctx(struct drm_crtc *crtc)
-{
-	if (crtc->acquire_ctx)
-		return crtc->acquire_ctx;
-
-	WARN_ON(!crtc->dev->mode_config.acquire_ctx);
-
-	return crtc->dev->mode_config.acquire_ctx;
-}
-EXPORT_SYMBOL(drm_modeset_legacy_acquire_ctx);
-
 /**
  * drm_warn_on_modeset_not_all_locked - check that all modeset locks are locked
  * @dev: device

drivers/gpu/drm/i915/intel_display.c

@@ -10715,7 +10715,7 @@ out_hang:
 		state = drm_atomic_state_alloc(dev);
 		if (!state)
 			return -ENOMEM;
-		state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
+		state->acquire_ctx = dev->mode_config.acquire_ctx;
 
 retry:
 		plane_state = drm_atomic_get_plane_state(state, primary);
@@ -13075,7 +13075,7 @@ void intel_crtc_restore_mode(struct drm_crtc *crtc)
 		return;
 	}
 
-	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
+	state->acquire_ctx = crtc->dev->mode_config.acquire_ctx;
 
 retry:
 	crtc_state = drm_atomic_get_crtc_state(state, crtc);

drivers/gpu/drm/i915/intel_pipe_crc.c

@@ -522,7 +522,7 @@ static void hsw_trans_edp_pipe_A_crc_wa(struct drm_i915_private *dev_priv,
 		goto unlock;
 	}
 
-	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(&crtc->base);
+	state->acquire_ctx = crtc->base.dev->mode_config.acquire_ctx;
 	pipe_config = intel_atomic_get_crtc_state(state, crtc);
 	if (IS_ERR(pipe_config)) {
 		ret = PTR_ERR(pipe_config);

include/drm/drm_crtc.h

@@ -782,15 +782,6 @@ struct drm_crtc {
 	 */
 	spinlock_t commit_lock;
 
-	/**
-	 * @acquire_ctx:
-	 *
-	 * Per-CRTC implicit acquire context used by atomic drivers for legacy
-	 * IOCTLs, so that atomic drivers can get at the locking acquire
-	 * context.
-	 */
-	struct drm_modeset_acquire_ctx *acquire_ctx;
-
 #ifdef CONFIG_DEBUG_FS
 	/**
 	 * @debugfs_entry:

include/drm/drm_modeset_lock.h

@@ -122,8 +122,6 @@ struct drm_plane;
 void drm_modeset_lock_all(struct drm_device *dev);
 void drm_modeset_unlock_all(struct drm_device *dev);
 void drm_warn_on_modeset_not_all_locked(struct drm_device *dev);
-struct drm_modeset_acquire_ctx *
-drm_modeset_legacy_acquire_ctx(struct drm_crtc *crtc);
 
 int drm_modeset_lock_all_ctx(struct drm_device *dev,
 			     struct drm_modeset_acquire_ctx *ctx);