crtc/kms: Outsource CRTC state fetching to MetaKmsCrtc

Move reading state into a struct for MetaCrtcKms to use instead of
querying KMS itself. The state is fetched in the impl context, but
consists of only simple data types, so is made accessible publicly. As
of this, MetaCrtcKms construction does not involve any manual KMS
interaction outside of the MetaKms abstraction.

https://gitlab.gnome.org/GNOME/mutter/issues/548
https://gitlab.gnome.org/GNOME/mutter/merge_requests/525

src/backends/native/meta-crtc-kms.c

@@ -495,26 +495,24 @@ meta_crtc_destroy_notify (MetaCrtc *crtc)
 
 MetaCrtc *
 meta_create_kms_crtc (MetaGpuKms  *gpu_kms,
-                      MetaKmsCrtc  *kms_crtc,
-                      drmModeCrtc  *drm_crtc)
+                      MetaKmsCrtc *kms_crtc)
 {
   MetaGpu *gpu = META_GPU (gpu_kms);
   MetaCrtc *crtc;
   MetaCrtcKms *crtc_kms;
+  const MetaKmsCrtcState *crtc_state;
+
+  crtc_state = meta_kms_crtc_get_current_state (kms_crtc);
 
   crtc = g_object_new (META_TYPE_CRTC, NULL);
-
   crtc->gpu = gpu;
   crtc->crtc_id = meta_kms_crtc_get_id (kms_crtc);
-  crtc->rect.x = drm_crtc->x;
-  crtc->rect.y = drm_crtc->y;
-  crtc->rect.width = drm_crtc->width;
-  crtc->rect.height = drm_crtc->height;
+  crtc->rect = crtc_state->rect;
   crtc->is_dirty = FALSE;
   crtc->transform = META_MONITOR_TRANSFORM_NORMAL;
   crtc->all_transforms = ALL_TRANSFORMS_MASK;
 
-  if (drm_crtc->mode_valid)
+  if (crtc_state->is_drm_mode_valid)
     {
       GList *l;
 
@@ -522,7 +520,7 @@ meta_create_kms_crtc (MetaGpuKms   *gpu_kms,
         {
           MetaCrtcMode *mode = l->data;
 
-          if (meta_drm_mode_equal (&drm_crtc->mode, mode->driver_private))
+          if (meta_drm_mode_equal (&crtc_state->drm_mode, mode->driver_private))
             {
               crtc->current_mode = mode;
               break;

src/backends/native/meta-crtc-kms.h

@@ -56,7 +56,6 @@ meta_crtc_kms_supports_format (MetaCrtc *crtc,
                                uint32_t  drm_format);
 
 MetaCrtc * meta_create_kms_crtc (MetaGpuKms  *gpu_kms,
-                                 MetaKmsCrtc  *kms_crtc,
-                                 drmModeCrtc  *drm_crtc);
+                                 MetaKmsCrtc *kms_crtc);
 
 #endif /* META_CRTC_KMS_H */

src/backends/native/meta-gpu-kms.c

@@ -703,8 +703,7 @@ init_modes (MetaGpuKms *gpu_kms,
 }
 
 static void
-init_crtcs (MetaGpuKms       *gpu_kms,
-            MetaKmsResources *resources)
+init_crtcs (MetaGpuKms *gpu_kms)
 {
   MetaGpu *gpu = META_GPU (gpu_kms);
   MetaKmsDevice *kms_device = gpu_kms->kms_device;
@@ -716,15 +715,9 @@ init_crtcs (MetaGpuKms       *gpu_kms,
   for (l = meta_kms_device_get_crtcs (kms_device); l; l = l->next)
     {
       MetaKmsCrtc *kms_crtc = l->data;
-      int crtc_idx;
-      drmModeCrtc *drm_crtc;
       MetaCrtc *crtc;
 
-      crtc_idx = meta_kms_crtc_get_idx (kms_crtc);
-      drm_crtc = drmModeGetCrtc (gpu_kms->fd,
-                                 resources->resources->crtcs[crtc_idx]);
-      crtc = meta_create_kms_crtc (gpu_kms, kms_crtc, drm_crtc);
-      drmModeFreeCrtc (drm_crtc);
+      crtc = meta_create_kms_crtc (gpu_kms, kms_crtc);
 
       crtcs = g_list_append (crtcs, crtc);
     }
@@ -868,7 +861,7 @@ meta_gpu_kms_read_current (MetaGpu  *gpu,
 
   init_connectors (gpu_kms, resources.resources);
   init_modes (gpu_kms, resources.resources);
-  init_crtcs (gpu_kms, &resources);
+  init_crtcs (gpu_kms);
   init_outputs (gpu_kms, &resources);
   init_frame_clock (gpu_kms);
 

src/backends/native/meta-kms-crtc-private.h

@@ -28,4 +28,6 @@ MetaKmsCrtc * meta_kms_crtc_new (MetaKmsImplDevice *impl_device,
                                  drmModeCrtc       *drm_crtc,
                                  int                idx);
 
+void meta_kms_crtc_update_state (MetaKmsCrtc *crtc);
+
 #endif /* META_KMS_CRTC_PRIVATE_H */

src/backends/native/meta-kms-crtc.c

@@ -22,6 +22,7 @@
 #include "backends/native/meta-kms-crtc.h"
 #include "backends/native/meta-kms-crtc-private.h"
 
+#include "backends/native/meta-kms-device-private.h"
 #include "backends/native/meta-kms-impl-device.h"
 
 struct _MetaKmsCrtc
@@ -32,6 +33,8 @@ struct _MetaKmsCrtc
 
   uint32_t id;
   int idx;
+
+  MetaKmsCrtcState current_state;
 };
 
 G_DEFINE_TYPE (MetaKmsCrtc, meta_kms_crtc, G_TYPE_OBJECT)
@@ -42,6 +45,12 @@ meta_kms_crtc_get_device (MetaKmsCrtc *crtc)
   return crtc->device;
 }
 
+const MetaKmsCrtcState *
+meta_kms_crtc_get_current_state (MetaKmsCrtc *crtc)
+{
+  return &crtc->current_state;
+}
+
 uint32_t
 meta_kms_crtc_get_id (MetaKmsCrtc *crtc)
 {
@@ -54,6 +63,36 @@ meta_kms_crtc_get_idx (MetaKmsCrtc *crtc)
   return crtc->idx;
 }
 
+static void
+meta_kms_crtc_read_state (MetaKmsCrtc       *crtc,
+                          MetaKmsImplDevice *impl_device,
+                          drmModeCrtc       *drm_crtc)
+{
+  crtc->current_state = (MetaKmsCrtcState) {
+    .rect = {
+      .x = drm_crtc->x,
+      .y = drm_crtc->y,
+      .width = drm_crtc->width,
+      .height = drm_crtc->height,
+    },
+    .is_drm_mode_valid = drm_crtc->mode_valid,
+    .drm_mode = drm_crtc->mode,
+  };
+}
+
+void
+meta_kms_crtc_update_state (MetaKmsCrtc *crtc)
+{
+  MetaKmsImplDevice *impl_device;
+  drmModeCrtc *drm_crtc;
+
+  impl_device = meta_kms_device_get_impl_device (crtc->device);
+  drm_crtc = drmModeGetCrtc (meta_kms_impl_device_get_fd (impl_device),
+                             crtc->id);
+  meta_kms_crtc_read_state (crtc, impl_device, drm_crtc);
+  drmModeFreeCrtc (drm_crtc);
+}
+
 MetaKmsCrtc *
 meta_kms_crtc_new (MetaKmsImplDevice *impl_device,
                    drmModeCrtc       *drm_crtc,

src/backends/native/meta-kms-crtc.h

@@ -25,6 +25,18 @@
 #include <xf86drmMode.h>
 
 #include "backends/native/meta-kms-types.h"
+#include "meta/boxes.h"
+
+typedef struct _MetaKmsCrtcState
+{
+  MetaRectangle rect;
+  gboolean is_drm_mode_valid;
+  drmModeModeInfo drm_mode;
+
+  uint32_t common_possible_crtcs;
+  uint32_t common_possible_clones;
+  uint32_t encoder_device_idxs;
+} MetaKmsCrtcState;
 
 #define META_TYPE_KMS_CRTC (meta_kms_crtc_get_type ())
 G_DECLARE_FINAL_TYPE (MetaKmsCrtc, meta_kms_crtc,
@@ -33,6 +45,8 @@ G_DECLARE_FINAL_TYPE (MetaKmsCrtc, meta_kms_crtc,
 
 MetaKmsDevice * meta_kms_crtc_get_device (MetaKmsCrtc *crtc);
 
+const MetaKmsCrtcState * meta_kms_crtc_get_current_state (MetaKmsCrtc *crtc);
+
 uint32_t meta_kms_crtc_get_id (MetaKmsCrtc *crtc);
 
 int meta_kms_crtc_get_idx (MetaKmsCrtc *crtc);

src/backends/native/meta-kms-device-private.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2019 Red Hat
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#ifndef META_KMS_DEVICE_PRIVATE_H
+#define META_KMS_DEVICE_PRIVATE_H
+
+#include "backends/native/meta-kms-types.h"
+
+MetaKmsImplDevice * meta_kms_device_get_impl_device (MetaKmsDevice *device);
+
+#endif /* META_KMS_DEVICE_PRIVATE_H */

src/backends/native/meta-kms-device.c

@@ -19,6 +19,7 @@
 
 #include "config.h"
 
+#include "backends/native/meta-kms-device-private.h"
 #include "backends/native/meta-kms-device.h"
 
 #include "backends/native/meta-backend-native.h"
@@ -44,6 +45,12 @@ struct _MetaKmsDevice
 
 G_DEFINE_TYPE (MetaKmsDevice, meta_kms_device, G_TYPE_OBJECT);
 
+MetaKmsImplDevice *
+meta_kms_device_get_impl_device (MetaKmsDevice *device)
+{
+  return device->impl_device;
+}
+
 int
 meta_kms_device_leak_fd (MetaKmsDevice *device)
 {

src/backends/native/meta-kms-impl-device.c

@@ -216,6 +216,15 @@ init_planes (MetaKmsImplDevice *impl_device)
   impl_device->planes = g_list_reverse (impl_device->planes);
 }
 
+void
+meta_kms_impl_device_update_states (MetaKmsImplDevice *impl_device)
+{
+  meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl_device->impl));
+
+  g_list_foreach (impl_device->crtcs, (GFunc) meta_kms_crtc_update_state,
+                  NULL);
+}
+
 MetaKmsImplDevice *
 meta_kms_impl_device_new (MetaKmsDevice *device,
                           MetaKmsImpl   *impl,

src/backends/native/meta-kms-impl-device.h

@@ -49,6 +49,8 @@ int meta_kms_impl_device_get_fd (MetaKmsImplDevice *impl_device);
 
 int meta_kms_impl_device_leak_fd (MetaKmsImplDevice *impl_device);
 
+void meta_kms_impl_device_update_states (MetaKmsImplDevice *impl_device);
+
 int meta_kms_impl_device_close (MetaKmsImplDevice *impl_device);
 
 MetaKmsImplDevice * meta_kms_impl_device_new (MetaKmsDevice *device,

src/backends/native/meta-kms.c

@@ -21,8 +21,11 @@
 
 #include "backends/native/meta-kms-private.h"
 
+#include "backends/native/meta-backend-native.h"
+#include "backends/native/meta-kms-device-private.h"
 #include "backends/native/meta-kms-impl.h"
 #include "backends/native/meta-kms-impl-simple.h"
+#include "backends/native/meta-udev.h"
 
 struct _MetaKms
 {
@@ -30,6 +33,8 @@ struct _MetaKms
 
   MetaBackend *backend;
 
+  guint hotplug_handler_id;
+
   MetaKmsImpl *impl;
   gboolean in_impl_task;
 
@@ -59,6 +64,45 @@ meta_kms_in_impl_task (MetaKms *kms)
   return kms->in_impl_task;
 }
 
+static gboolean
+update_states_in_impl (MetaKmsImpl  *impl,
+                       gpointer      user_data,
+                       GError      **error)
+{
+  MetaKms *kms = user_data;
+  GList *l;
+
+  for (l = kms->devices; l; l = l->next)
+    {
+      MetaKmsDevice *device = l->data;
+      MetaKmsImplDevice *impl_device = meta_kms_device_get_impl_device (device);
+
+      meta_kms_impl_device_update_states (impl_device);
+    }
+
+  return TRUE;
+}
+
+static gboolean
+meta_kms_update_states_sync (MetaKms  *kms,
+                             GError  **error)
+{
+  return meta_kms_run_impl_task_sync (kms,
+                                      update_states_in_impl,
+                                      kms,
+                                      error);
+}
+
+static void
+on_udev_hotplug (MetaUdev *udev,
+                 MetaKms  *kms)
+{
+  g_autoptr (GError) error = NULL;
+
+  if (!meta_kms_update_states_sync (kms, &error))
+    g_warning ("Updating KMS state failed: %s", error->message);
+}
+
 MetaBackend *
 meta_kms_get_backend (MetaKms *kms)
 {
@@ -86,6 +130,8 @@ MetaKms *
 meta_kms_new (MetaBackend  *backend,
               GError      **error)
 {
+  MetaBackendNative *backend_native = META_BACKEND_NATIVE (backend);
+  MetaUdev *udev = meta_backend_native_get_udev (backend_native);
   MetaKms *kms;
 
   kms = g_object_new (META_TYPE_KMS, NULL);
@@ -97,6 +143,9 @@ meta_kms_new (MetaBackend  *backend,
       return NULL;
     }
 
+  kms->hotplug_handler_id =
+    g_signal_connect (udev, "hotplug", G_CALLBACK (on_udev_hotplug), kms);
+
   return kms;
 }
 
@@ -104,9 +153,14 @@ static void
 meta_kms_finalize (GObject *object)
 {
   MetaKms *kms = META_KMS (object);
+  MetaBackendNative *backend_native = META_BACKEND_NATIVE (kms->backend);
+  MetaUdev *udev = meta_backend_native_get_udev (backend_native);
 
   g_list_free_full (kms->devices, g_object_unref);
 
+  if (kms->hotplug_handler_id)
+    g_signal_handler_disconnect (udev, kms->hotplug_handler_id);
+
   G_OBJECT_CLASS (meta_kms_parent_class)->finalize (object);
 }
 

src/backends/native/meta-monitor-manager-kms.c

@@ -412,7 +412,8 @@ meta_monitor_manager_kms_connect_hotplug_handler (MetaMonitorManagerKms *manager
   MetaUdev *udev = meta_backend_native_get_udev (META_BACKEND_NATIVE (backend));
 
   manager_kms->hotplug_handler_id =
-    g_signal_connect (udev, "hotplug", G_CALLBACK (on_udev_hotplug), manager);
+    g_signal_connect_after (udev, "hotplug",
+                            G_CALLBACK (on_udev_hotplug), manager);
 }
 
 static void

src/meson.build

@@ -601,6 +601,7 @@ if have_native_backend
     'backends/native/meta-kms-crtc-private.h',
     'backends/native/meta-kms-crtc.c',
     'backends/native/meta-kms-crtc.h',
+    'backends/native/meta-kms-device-private.h',
     'backends/native/meta-kms-device.c',
     'backends/native/meta-kms-device.h',
     'backends/native/meta-kms-impl-device.c',