[mutter] backends/native: Don't set discarded framebuffer as current

[Jonas Ådahl <jadahl src gnome org>]

commit ad784501a6139af7d9dbc44c1b5a857d6319cf26
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Nov 17 20:17:15 2016 +0800

    backends/native: Don't set discarded framebuffer as current
    
    When a swap failed with EACCES (possibly due to VT switching), don't
    mark the framebuffer as 'in use', so that it'll be cleaned up properly
    and not set as current.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=773629

 src/backends/native/meta-monitor-manager-kms.c |   27 +++++++++++++++++------
 src/backends/native/meta-monitor-manager-kms.h |   13 ++++++-----
 src/backends/native/meta-renderer-native.c     |    5 +--
 3 files changed, 29 insertions(+), 16 deletions(-)
---
diff --git a/src/backends/native/meta-monitor-manager-kms.c b/src/backends/native/meta-monitor-manager-kms.c
index 2067f31..fae195f 100644
--- a/src/backends/native/meta-monitor-manager-kms.c
+++ b/src/backends/native/meta-monitor-manager-kms.c
@@ -1546,7 +1546,7 @@ get_crtc_connectors (MetaMonitorManager *manager,
   *connectors = (uint32_t *) g_array_free (connectors_array, FALSE);
 }
 
-void
+gboolean
 meta_monitor_manager_kms_apply_crtc_mode (MetaMonitorManagerKms *manager_kms,
                                           MetaCRTC              *crtc,
                                           int                    x,
@@ -1571,9 +1571,14 @@ meta_monitor_manager_kms_apply_crtc_mode (MetaMonitorManagerKms *manager_kms,
                       x, y,
                       connectors, n_connectors,
                       mode) != 0)
-    g_warning ("Failed to set CRTC mode %s: %m", crtc->current_mode->name);
+    {
+      g_warning ("Failed to set CRTC mode %s: %m", crtc->current_mode->name);
+      return FALSE;
+    }
 
   g_free (connectors);
+
+  return TRUE;
 }
 
 static void
@@ -1622,7 +1627,8 @@ meta_monitor_manager_kms_flip_crtc (MetaMonitorManagerKms *manager_kms,
                                     int                    x,
                                     int                    y,
                                     uint32_t               fb_id,
-                                    GClosure              *flip_closure)
+                                    GClosure              *flip_closure,
+                                    gboolean              *fb_in_use)
 {
   MetaMonitorManager *manager = META_MONITOR_MANAGER (manager_kms);
   uint32_t *connectors;
@@ -1649,14 +1655,21 @@ meta_monitor_manager_kms_flip_crtc (MetaMonitorManagerKms *manager_kms,
     }
 
   if (manager_kms->page_flips_not_supported)
-    meta_monitor_manager_kms_apply_crtc_mode (manager_kms,
-                                              crtc,
-                                              x, y,
-                                              fb_id);
+    {
+      if (meta_monitor_manager_kms_apply_crtc_mode (manager_kms,
+                                                    crtc,
+                                                    x, y,
+                                                    fb_id))
+        {
+          *fb_in_use = TRUE;
+          return FALSE;
+        }
+    }
 
   if (ret != 0)
     return FALSE;
 
+  *fb_in_use = TRUE;
   g_closure_ref (flip_closure);
 
   return TRUE;
diff --git a/src/backends/native/meta-monitor-manager-kms.h b/src/backends/native/meta-monitor-manager-kms.h
index 53a019e..96468cf 100644
--- a/src/backends/native/meta-monitor-manager-kms.h
+++ b/src/backends/native/meta-monitor-manager-kms.h
@@ -39,11 +39,11 @@ GType meta_monitor_manager_kms_get_type (void);
 
 typedef void (*MetaKmsFlipCallback) (void *user_data);
 
-void meta_monitor_manager_kms_apply_crtc_mode (MetaMonitorManagerKms *manager_kms,
-                                               MetaCRTC              *crtc,
-                                               int                    x,
-                                               int                    y,
-                                               uint32_t               fb_id);
+gboolean meta_monitor_manager_kms_apply_crtc_mode (MetaMonitorManagerKms *manager_kms,
+                                                   MetaCRTC              *crtc,
+                                                   int                    x,
+                                                   int                    y,
+                                                   uint32_t               fb_id);
 
 gboolean meta_monitor_manager_kms_is_crtc_active (MetaMonitorManagerKms *manager_kms,
                                                   MetaCRTC              *crtc);
@@ -53,7 +53,8 @@ gboolean meta_monitor_manager_kms_flip_crtc (MetaMonitorManagerKms *manager_kms,
                                              int                    x,
                                              int                    y,
                                              uint32_t               fb_id,
-                                             GClosure              *flip_closure);
+                                             GClosure              *flip_closure,
+                                             gboolean              *fb_in_use);
 
 void meta_monitor_manager_kms_wait_for_flip (MetaMonitorManagerKms *manager_kms);
 
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index 8a46dc4..9acf7fc 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -457,10 +457,9 @@ meta_onscreen_native_flip_crtc (MetaOnscreenNative *onscreen_native,
                                           crtc,
                                           x, y,
                                           onscreen_native->gbm.next_fb_id,
-                                          flip_closure))
+                                          flip_closure,
+                                          fb_in_use))
     onscreen_native->pending_flips++;
-
-  *fb_in_use = TRUE;
 }
 
 static void