kms/device: Use device pool to open/close dri devices

This replaces the usage of MetaLauncher.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1828>

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

@@ -28,7 +28,8 @@
 #include <sys/types.h>
 #include <xf86drm.h>
 
-#include "backends/native/meta-backend-native.h"
+#include "backends/native/meta-backend-native-private.h"
+#include "backends/native/meta-device-pool.h"
 #include "backends/native/meta-kms-impl-device-atomic.h"
 #include "backends/native/meta-kms-impl-device-dummy.h"
 #include "backends/native/meta-kms-impl-device-simple.h"
@@ -229,7 +230,7 @@ meta_kms_device_add_fake_plane_in_impl (MetaKmsDevice    *device,
 typedef struct _CreateImplDeviceData
 {
   MetaKmsDevice *device;
-  int fd;
+  MetaDeviceFile *device_file;
   const char *path;
   MetaKmsDeviceFlag flags;
 
@@ -281,7 +282,7 @@ get_driver_info (int    fd,
 static MetaKmsImplDevice *
 meta_create_kms_impl_device (MetaKmsDevice      *device,
                              MetaKmsImpl        *impl,
-                             int                 fd,
+                             MetaDeviceFile     *device_file,
                              const char         *path,
                              MetaKmsDeviceFlag   flags,
                              GError            **error)
@@ -291,12 +292,13 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
   g_autofree char *driver_name = NULL;
   g_autofree char *driver_description = NULL;
   const char *atomic_kms_enable_env;
-  int impl_fd;
+  int fd;
-  g_autofree char *impl_path = NULL;
+  g_autoptr (MetaDeviceFile) impl_device_file = NULL;
   MetaKmsImplDevice *impl_device;
 
   meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl));
 
+  fd = meta_device_file_get_fd (device_file);
   if (!get_driver_info (fd, &driver_name, &driver_description))
     {
       driver_name = g_strdup ("unknown");
@@ -308,6 +310,7 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
   if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
     {
       g_autofree char *render_node_path = NULL;
+      MetaDevicePool *device_pool;
 
       render_node_path = drmGetRenderDeviceNameFromFd (fd);
       if (!render_node_path)
@@ -318,19 +321,17 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
           return NULL;
         }
 
-      impl_fd = open (render_node_path, O_RDWR | O_CLOEXEC, 0);
+      device_pool = meta_device_file_get_pool (device_file);
-      if (impl_fd == -1)
+
-        {
+      impl_device_file = meta_device_pool_open (device_pool, render_node_path,
-          g_set_error (error, G_IO_ERROR, g_io_error_from_errno (errno),
+                                                META_DEVICE_FILE_FLAG_NONE,
-                       "Failed to open render node '%s': %s",
+                                                error);
-                       render_node_path, g_strerror (errno));
+      if (!impl_device_file)
-          return NULL;
+        return NULL;
-        }
 
       g_message ("Adding device '%s' (from '%s', %s) using no mode setting.",
                  render_node_path, path, driver_name);
 
-      impl_path = g_steal_pointer (&render_node_path);
       impl_device_type = META_TYPE_KMS_IMPL_DEVICE_DUMMY;
     }
   else if (atomic_kms_enable_env)
@@ -355,8 +356,7 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
                    atomic_kms_enable_env);
         }
 
-      impl_fd = dup (fd);
+      impl_device_file = meta_device_file_acquire (device_file);
-      impl_path = g_strdup (path);
 
       g_message ("Mode setting implementation for '%s' (%s) forced (%s).",
                  path, driver_name,
@@ -368,8 +368,7 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
       g_message ("Adding device '%s' (%s) using non-atomic mode setting"
                  " (using atomic mode setting not allowed).",
                  path, driver_name);
-      impl_fd = dup (fd);
+      impl_device_file = meta_device_file_acquire (device_file);
-      impl_path = g_strdup (path);
       impl_device_type = META_TYPE_KMS_IMPL_DEVICE_SIMPLE;
     }
   else
@@ -395,26 +394,19 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
           impl_device_type = META_TYPE_KMS_IMPL_DEVICE_SIMPLE;
         }
 
-      impl_fd = dup (fd);
+      impl_device_file = meta_device_file_acquire (device_file);
-      impl_path = g_strdup (path);
     }
 
   impl_device = g_initable_new (impl_device_type, NULL, error,
                                 "device", device,
                                 "impl", impl,
-                                "fd", impl_fd,
+                                "device-file", impl_device_file,
-                                "path", impl_path,
                                 "flags", flags,
                                 "driver-name", driver_name,
                                 "driver-description", driver_description,
                                 NULL);
   if (!impl_device)
-    {
+    return NULL;
-      close (impl_fd);
-      return NULL;
-    }
-
-  close (fd);
 
   return impl_device;
 }
@@ -429,7 +421,7 @@ create_impl_device_in_impl (MetaKmsImpl  *impl,
 
   impl_device = meta_create_kms_impl_device (data->device,
                                              impl,
-                                             data->fd,
+                                             data->device_file,
                                              data->path,
                                              data->flags,
                                              error);
@@ -462,44 +454,33 @@ meta_kms_device_new (MetaKms            *kms,
 {
   MetaBackend *backend = meta_kms_get_backend (kms);
   MetaBackendNative *backend_native = META_BACKEND_NATIVE (backend);
-  MetaLauncher *launcher = meta_backend_native_get_launcher (backend_native);
+  MetaDevicePool *device_pool =
+    meta_backend_native_get_device_pool (backend_native);
   MetaKmsDevice *device;
   CreateImplDeviceData data;
-  int fd;
+  g_autoptr (MetaDeviceFile) device_file = NULL;
+  MetaDeviceFileFlags device_file_flags;
 
-  if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
+  device_file_flags = META_DEVICE_FILE_FLAG_NONE;
-    {
+  if (!(flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING))
-      fd = open (path, O_RDWR | O_CLOEXEC, 0);
+    device_file_flags |= META_DEVICE_FILE_FLAG_TAKE_CONTROL;
-      if (fd == -1)
+
-        {
+  device_file = meta_device_pool_open (device_pool, path, flags, error);
-          g_set_error (error, G_IO_ERROR, g_io_error_from_errno (errno),
+  if (!device_file)
-                       "Failed to open DRM device: %s", g_strerror (errno));
+    return NULL;
-          return NULL;
-        }
-    }
-  else
-    {
-      fd = meta_launcher_open_restricted (launcher, path, error);
-      if (fd == -1)
-        return NULL;
-    }
 
   device = g_object_new (META_TYPE_KMS_DEVICE, NULL);
   device->kms = kms;
 
   data = (CreateImplDeviceData) {
     .device = device,
-    .fd = fd,
+    .device_file = device_file,
     .path = path,
     .flags = flags,
   };
   if (!meta_kms_run_impl_task_sync (kms, create_impl_device_in_impl, &data,
                                     error))
     {
-      if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
-        close (fd);
-      else
-        meta_launcher_close_restricted (launcher, fd);
       g_object_unref (device);
       return NULL;
     }
@@ -520,27 +501,15 @@ meta_kms_device_new (MetaKms            *kms,
   return device;
 }
 
-typedef struct _FreeImplDeviceData
-{
-  MetaKmsImplDevice *impl_device;
-
-  int out_fd;
-} FreeImplDeviceData;
-
 static gpointer
 free_impl_device_in_impl (MetaKmsImpl  *impl,
                           gpointer      user_data,
                           GError      **error)
 {
-  FreeImplDeviceData *data = user_data;
+  MetaKmsImplDevice *impl_device = user_data;
-  MetaKmsImplDevice *impl_device = data->impl_device;
-  int fd;
 
-  fd = meta_kms_impl_device_close (impl_device);
   g_object_unref (impl_device);
 
-  data->out_fd = fd;
-
   return GINT_TO_POINTER (TRUE);
 }
 
@@ -548,9 +517,6 @@ static void
 meta_kms_device_finalize (GObject *object)
 {
   MetaKmsDevice *device = META_KMS_DEVICE (object);
-  MetaBackend *backend = meta_kms_get_backend (device->kms);
-  MetaBackendNative *backend_native = META_BACKEND_NATIVE (backend);
-  MetaLauncher *launcher = meta_backend_native_get_launcher (backend_native);
 
   g_free (device->path);
   g_list_free (device->crtcs);
@@ -559,26 +525,11 @@ meta_kms_device_finalize (GObject *object)
 
   if (device->impl_device)
     {
-      FreeImplDeviceData data;
+      meta_kms_run_impl_task_sync (device->kms, free_impl_device_in_impl,
-      GError *error = NULL;
+                                   device->impl_device,
-
+                                   NULL);
-      data = (FreeImplDeviceData) {
-        .impl_device = device->impl_device,
-      };
-      if (!meta_kms_run_impl_task_sync (device->kms, free_impl_device_in_impl, &data,
-                                        &error))
-        {
-          g_warning ("Failed to close KMS impl device: %s", error->message);
-          g_error_free (error);
-        }
-      else
-        {
-          if (device->flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
-            close (data.out_fd);
-          else
-            meta_launcher_close_restricted (launcher, data.out_fd);
-        }
     }
+
   G_OBJECT_CLASS (meta_kms_device_parent_class)->finalize (object);
 }
 

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

@@ -24,6 +24,8 @@
 #include <errno.h>
 #include <xf86drm.h>
 
+#include "backends/native/meta-backend-native.h"
+#include "backends/native/meta-device-pool.h"
 #include "backends/native/meta-kms-connector-private.h"
 #include "backends/native/meta-kms-connector.h"
 #include "backends/native/meta-kms-crtc-private.h"
@@ -45,8 +47,7 @@ enum
 
   PROP_DEVICE,
   PROP_IMPL,
-  PROP_FD,
+  PROP_DEVICE_FILE,
-  PROP_PATH,
   PROP_FLAGS,
   PROP_DRIVER_NAME,
   PROP_DRIVER_DESCRIPTION,
@@ -61,7 +62,7 @@ typedef struct _MetaKmsImplDevicePrivate
   MetaKmsDevice *device;
   MetaKmsImpl *impl;
 
-  int fd;
+  MetaDeviceFile *device_file;
   GSource *fd_source;
   char *path;
   MetaKmsDeviceFlag flags;
@@ -197,6 +198,7 @@ meta_kms_impl_device_dispatch (MetaKmsImplDevice  *impl_device,
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
   MetaKmsImplDeviceClass *klass = META_KMS_IMPL_DEVICE_GET_CLASS (impl_device);
+  int fd;
 
   drmEventContext drm_event_context;
 
@@ -205,9 +207,11 @@ meta_kms_impl_device_dispatch (MetaKmsImplDevice  *impl_device,
   drm_event_context = (drmEventContext) { 0 };
   klass->setup_drm_event_context (impl_device, &drm_event_context);
 
+  fd = meta_device_file_get_fd (priv->device_file);
+
   while (TRUE)
     {
-      if (drmHandleEvent (priv->fd, &drm_event_context) != 0)
+      if (drmHandleEvent (fd, &drm_event_context) != 0)
         {
           struct pollfd pfd;
           int ret;
@@ -220,7 +224,7 @@ meta_kms_impl_device_dispatch (MetaKmsImplDevice  *impl_device,
               return FALSE;
             }
 
-          pfd.fd = priv->fd;
+          pfd.fd = fd;
           pfd.events = POLL_IN | POLL_ERR;
           do
             {
@@ -257,15 +261,18 @@ meta_kms_impl_device_find_property (MetaKmsImplDevice       *impl_device,
 {
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
+  int fd;
   unsigned int i;
 
   meta_assert_in_kms_impl (meta_kms_impl_get_kms (priv->impl));
 
+  fd = meta_device_file_get_fd (priv->device_file);
+
   for (i = 0; i < props->count_props; i++)
     {
       drmModePropertyPtr prop;
 
-      prop = drmModeGetProperty (priv->fd, props->props[i]);
+      prop = drmModeGetProperty (fd, props->props[i]);
       if (!prop)
         continue;
 
@@ -286,9 +293,10 @@ init_caps (MetaKmsImplDevice *impl_device)
 {
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
-  int fd = priv->fd;
+  int fd;
   uint64_t cursor_width, cursor_height;
 
+  fd = meta_device_file_get_fd (priv->device_file);
   if (drmGetCap (fd, DRM_CAP_CURSOR_WIDTH, &cursor_width) == 0 &&
       drmGetCap (fd, DRM_CAP_CURSOR_HEIGHT, &cursor_height) == 0)
     {
@@ -305,6 +313,9 @@ init_crtcs (MetaKmsImplDevice *impl_device,
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
   int idx;
+  int fd;
+
+  fd = meta_device_file_get_fd (priv->device_file);
 
   for (idx = 0; idx < drm_resources->count_crtcs; idx++)
     {
@@ -314,7 +325,7 @@ init_crtcs (MetaKmsImplDevice *impl_device,
       g_autoptr (GError) error = NULL;
 
       crtc_id = drm_resources->crtcs[idx];
-      drm_crtc = drmModeGetCrtc (priv->fd, crtc_id);
+      drm_crtc = drmModeGetCrtc (fd, crtc_id);
       if (!drm_crtc)
         {
           g_warning ("Failed to get CRTC %u info on '%s': %s",
@@ -365,14 +376,16 @@ update_connectors (MetaKmsImplDevice *impl_device,
     meta_kms_impl_device_get_instance_private (impl_device);
   GList *connectors = NULL;
   unsigned int i;
+  int fd;
+
+  fd = meta_device_file_get_fd (priv->device_file);
 
   for (i = 0; i < drm_resources->count_connectors; i++)
     {
       drmModeConnector *drm_connector;
       MetaKmsConnector *connector;
 
-      drm_connector = drmModeGetConnector (priv->fd,
+      drm_connector = drmModeGetConnector (fd, drm_resources->connectors[i]);
-                                           drm_resources->connectors[i]);
       if (!drm_connector)
         continue;
 
@@ -510,10 +523,12 @@ init_planes (MetaKmsImplDevice *impl_device)
 {
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
-  int fd = priv->fd;
+  int fd;
   drmModePlaneRes *drm_planes;
   unsigned int i;
 
+  fd = meta_device_file_get_fd (priv->device_file);
+
   drm_planes = drmModeGetPlaneResources (fd);
   if (!drm_planes)
     return;
@@ -589,13 +604,15 @@ meta_kms_impl_device_update_states (MetaKmsImplDevice *impl_device)
 {
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
+  int fd;
   drmModeRes *drm_resources;
 
   meta_assert_in_kms_impl (meta_kms_impl_get_kms (priv->impl));
 
   meta_topic (META_DEBUG_KMS, "Updating device state for %s", priv->path);
 
-  drm_resources = drmModeGetResources (priv->fd);
+  fd = meta_device_file_get_fd (priv->device_file);
+  drm_resources = drmModeGetResources (fd);
   if (!drm_resources)
     {
       g_list_free_full (priv->planes, g_object_unref);
@@ -637,7 +654,7 @@ meta_kms_impl_device_get_fd (MetaKmsImplDevice *impl_device)
 
   meta_assert_in_kms_impl (meta_kms_impl_get_kms (priv->impl));
 
-  return priv->fd;
+  return meta_device_file_get_fd (priv->device_file);
 }
 
 int
@@ -646,7 +663,7 @@ meta_kms_impl_device_leak_fd (MetaKmsImplDevice *impl_device)
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
 
-  return priv->fd;
+  return meta_device_file_get_fd (priv->device_file);
 }
 
 MetaKmsFeedback *
@@ -676,22 +693,6 @@ meta_kms_impl_device_discard_pending_page_flips (MetaKmsImplDevice *impl_device)
   klass->discard_pending_page_flips (impl_device);
 }
 
-int
-meta_kms_impl_device_close (MetaKmsImplDevice *impl_device)
-{
-  MetaKmsImplDevicePrivate *priv =
-    meta_kms_impl_device_get_instance_private (impl_device);
-  int fd;
-
-  meta_assert_in_kms_impl (meta_kms_impl_get_kms (priv->impl));
-
-  g_clear_pointer (&priv->fd_source, g_source_destroy);
-  fd = priv->fd;
-  priv->fd = -1;
-
-  return fd;
-}
-
 static void
 meta_kms_impl_device_get_property (GObject    *object,
                                    guint       prop_id,
@@ -710,11 +711,8 @@ meta_kms_impl_device_get_property (GObject    *object,
     case PROP_IMPL:
       g_value_set_object (value, priv->impl);
       break;
-    case PROP_FD:
+    case PROP_DEVICE_FILE:
-      g_value_set_int (value, priv->fd);
+      g_value_set_pointer (value, priv->device_file);
-      break;
-    case PROP_PATH:
-      g_value_set_string (value, priv->path);
       break;
     case PROP_FLAGS:
       g_value_set_flags (value, priv->flags);
@@ -749,11 +747,9 @@ meta_kms_impl_device_set_property (GObject      *object,
     case PROP_IMPL:
       priv->impl = g_value_get_object (value);
       break;
-    case PROP_FD:
+    case PROP_DEVICE_FILE:
-      priv->fd = g_value_get_int (value);
+      priv->device_file =
-      break;
+        meta_device_file_acquire (g_value_get_pointer (value));
-    case PROP_PATH:
-      priv->path = g_value_dup_string (value);
       break;
     case PROP_FLAGS:
       priv->flags = g_value_get_flags (value);
@@ -784,6 +780,9 @@ meta_kms_impl_device_finalize (GObject *object)
   g_list_free_full (priv->connectors, g_object_unref);
   g_list_free_full (priv->fallback_modes,
                     (GDestroyNotify) meta_kms_mode_free);
+
+  g_clear_pointer (&priv->device_file, meta_device_file_release);
+
   g_free (priv->driver_name);
   g_free (priv->driver_description);
   g_free (priv->path);
@@ -797,10 +796,13 @@ meta_kms_impl_device_init_mode_setting (MetaKmsImplDevice  *impl_device,
 {
   MetaKmsImplDevicePrivate *priv =
     meta_kms_impl_device_get_instance_private (impl_device);
+  int fd;
   int ret;
   drmModeRes *drm_resources;
 
-  ret = drmSetClientCap (priv->fd, DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1);
+  fd = meta_device_file_get_fd (priv->device_file);
+
+  ret = drmSetClientCap (fd, DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1);
   if (ret != 0)
     {
       g_set_error (error, G_IO_ERROR, g_io_error_from_errno (-ret),
@@ -809,7 +811,7 @@ meta_kms_impl_device_init_mode_setting (MetaKmsImplDevice  *impl_device,
       return FALSE;
     }
 
-  drm_resources = drmModeGetResources (priv->fd);
+  drm_resources = drmModeGetResources (fd);
   if (!drm_resources)
     {
       g_set_error (error, G_IO_ERROR, g_io_error_from_errno (errno),
@@ -830,7 +832,8 @@ meta_kms_impl_device_init_mode_setting (MetaKmsImplDevice  *impl_device,
   drmModeFreeResources (drm_resources);
 
   priv->fd_source =
-    meta_kms_register_fd_in_impl (meta_kms_impl_get_kms (priv->impl), priv->fd,
+    meta_kms_register_fd_in_impl (meta_kms_impl_get_kms (priv->impl),
+                                  fd,
                                   kms_event_dispatch_in_impl,
                                   impl_device);
 
@@ -846,6 +849,18 @@ meta_kms_impl_device_prepare_shutdown (MetaKmsImplDevice *impl_device)
     klass->prepare_shutdown (impl_device);
 }
 
+static void
+meta_kms_impl_device_constructed (GObject *object)
+{
+  MetaKmsImplDevice *impl_device = META_KMS_IMPL_DEVICE (object);
+  MetaKmsImplDevicePrivate *priv =
+    meta_kms_impl_device_get_instance_private (impl_device);
+
+  priv->path = g_strdup (meta_device_file_get_path (priv->device_file));
+
+  G_OBJECT_CLASS (meta_kms_impl_device_parent_class)->constructed (object);
+}
+
 static void
 meta_kms_impl_device_init (MetaKmsImplDevice *impl_device)
 {
@@ -858,6 +873,7 @@ meta_kms_impl_device_class_init (MetaKmsImplDeviceClass *klass)
 
   object_class->get_property = meta_kms_impl_device_get_property;
   object_class->set_property = meta_kms_impl_device_set_property;
+  object_class->constructed = meta_kms_impl_device_constructed;
   object_class->finalize = meta_kms_impl_device_finalize;
 
   obj_props[PROP_DEVICE] =
@@ -876,22 +892,13 @@ meta_kms_impl_device_class_init (MetaKmsImplDeviceClass *klass)
                          G_PARAM_READWRITE |
                          G_PARAM_CONSTRUCT_ONLY |
                          G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_FD] =
+  obj_props[PROP_DEVICE_FILE] =
-    g_param_spec_int ("fd",
+    g_param_spec_pointer ("device-file",
-                      "fd",
+                          "device-file",
-                      "DRM device file descriptor",
+                          "Device file",
-                      INT_MIN, INT_MAX, 0,
+                          G_PARAM_READWRITE |
-                      G_PARAM_READWRITE |
+                          G_PARAM_CONSTRUCT_ONLY |
-                      G_PARAM_CONSTRUCT_ONLY |
+                          G_PARAM_STATIC_STRINGS);
-                      G_PARAM_STATIC_STRINGS);
-  obj_props[PROP_PATH] =
-    g_param_spec_string ("path",
-                         "path",
-                         "DRM device file path",
-                         NULL,
-                         G_PARAM_READWRITE |
-                         G_PARAM_CONSTRUCT_ONLY |
-                         G_PARAM_STATIC_STRINGS);
   obj_props[PROP_FLAGS] =
     g_param_spec_flags ("flags",
                         "flags",

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

@@ -142,8 +142,6 @@ void meta_kms_impl_device_handle_page_flip_callback (MetaKmsImplDevice   *impl_d
 
 void meta_kms_impl_device_discard_pending_page_flips (MetaKmsImplDevice *impl_device);
 
-int meta_kms_impl_device_close (MetaKmsImplDevice *impl_device);
-
 gboolean meta_kms_impl_device_init_mode_setting (MetaKmsImplDevice  *impl_device,
                                                  GError            **error);