[cogl/halfline/wip/render-node: 5/6] kms-winsys: rework handling of the drm fd

[Ray Strode <halfline src gnome org>]

commit e4b5dbb7a19fe567739ce4071fea20cac7b00cb1
Author: Ray Strode <rstrode redhat com>
Date:   Wed Aug 26 11:30:04 2015 -0400

    kms-winsys: rework handling of the drm fd
    
    At the moment the drm fd is stored in the renderer structure twice:
    once for reading and once for closing. This is a little messy, and
    will only get worse when we start throwing render nodes into the mix,
    too.
    
    This commit abstracts the device handling out to another structure.
    Rather than having two members for each fd, this commit employees a
    boolean to decide whether or not the fd needs to get explicitly closed.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=753531

 cogl/winsys/cogl-winsys-egl-kms.c |   66 +++++++++++++++++++-----------------
 1 files changed, 35 insertions(+), 31 deletions(-)
---
diff --git a/cogl/winsys/cogl-winsys-egl-kms.c b/cogl/winsys/cogl-winsys-egl-kms.c
index 5be832d..65e9d30 100644
--- a/cogl/winsys/cogl-winsys-egl-kms.c
+++ b/cogl/winsys/cogl-winsys-egl-kms.c
@@ -66,11 +66,16 @@ static const CoglWinsysEGLVtable _cogl_winsys_egl_vtable;
 
 static const CoglWinsysVtable *parent_vtable;
 
-typedef struct _CoglRendererKMS
+typedef struct _CoglRendererDeviceKMS
 {
   int fd;
-  int opened_fd;
   struct gbm_device *gbm;
+  CoglBool is_borrowed;
+} CoglRendererDeviceKMS;
+
+typedef struct _CoglRendererKMS
+{
+  CoglRendererDeviceKMS card_device;
   CoglClosure *swap_notify_idle;
   CoglBool     page_flips_not_supported;
 } CoglRendererKMS;
@@ -127,11 +132,11 @@ _cogl_winsys_renderer_disconnect (CoglRenderer *renderer)
   if (egl_renderer->edpy != EGL_NO_DISPLAY)
     eglTerminate (egl_renderer->edpy);
 
-  if (kms_renderer->gbm != NULL)
-    gbm_device_destroy (kms_renderer->gbm);
+  if (kms_renderer->card_device.gbm != NULL)
+    gbm_device_destroy (kms_renderer->card_device.gbm);
 
-  if (kms_renderer->opened_fd >= 0)
-    close (kms_renderer->opened_fd);
+  if (!kms_renderer->card_device.is_borrowed && kms_renderer->card_device.fd >= 0)
+    close (kms_renderer->card_device.fd);
 
   g_slice_free (CoglRendererKMS, kms_renderer);
   g_slice_free (CoglRendererEGL, egl_renderer);
@@ -191,7 +196,7 @@ free_current_bo (CoglOnscreen *onscreen)
 
   if (kms_onscreen->current_fb_id)
     {
-      drmModeRmFB (kms_renderer->fd,
+      drmModeRmFB (kms_renderer->card_device.fd,
                    kms_onscreen->current_fb_id);
       kms_onscreen->current_fb_id = 0;
     }
@@ -279,7 +284,7 @@ handle_drm_event (CoglRendererKMS *kms_renderer)
   memset (&evctx, 0, sizeof evctx);
   evctx.version = DRM_EVENT_CONTEXT_VERSION;
   evctx.page_flip_handler = page_flip_handler;
-  drmHandleEvent (kms_renderer->fd, &evctx);
+  drmHandleEvent (kms_renderer->card_device.fd, &evctx);
 }
 
 static void
@@ -309,20 +314,19 @@ _cogl_winsys_renderer_connect (CoglRenderer *renderer,
   egl_renderer->platform = g_slice_new0 (CoglRendererKMS);
   kms_renderer = egl_renderer->platform;
 
-  kms_renderer->fd = -1;
-  kms_renderer->opened_fd = -1;
+  kms_renderer->card_device.fd = -1;
 
   egl_renderer->edpy = EGL_NO_DISPLAY;
 
   if (renderer->kms_fd >= 0)
     {
-      kms_renderer->fd = renderer->kms_fd;
+      kms_renderer->card_device.fd = renderer->kms_fd;
+      kms_renderer->card_device.is_borrowed = TRUE;
     }
   else
     {
-      kms_renderer->opened_fd = open (card_device_name, O_RDWR);
-      kms_renderer->fd = kms_renderer->opened_fd;
-      if (kms_renderer->fd < 0)
+      kms_renderer->card_device.fd = open (card_device_name, O_RDWR);
+      if (kms_renderer->card_device.fd < 0)
         {
           /* Probably permissions error */
           _cogl_set_error (error, COGL_WINSYS_ERROR,
@@ -332,8 +336,8 @@ _cogl_winsys_renderer_connect (CoglRenderer *renderer,
         }
     }
 
-  kms_renderer->gbm = gbm_create_device (kms_renderer->fd);
-  if (kms_renderer->gbm == NULL)
+  kms_renderer->card_device.gbm = gbm_create_device (kms_renderer->card_device.fd);
+  if (kms_renderer->card_device.gbm == NULL)
     {
       _cogl_set_error (error, COGL_WINSYS_ERROR,
                    COGL_WINSYS_ERROR_INIT,
@@ -341,7 +345,7 @@ _cogl_winsys_renderer_connect (CoglRenderer *renderer,
       goto fail;
     }
 
-  egl_renderer->edpy = eglGetDisplay ((EGLNativeDisplayType)kms_renderer->gbm);
+  egl_renderer->edpy = eglGetDisplay ((EGLNativeDisplayType)kms_renderer->card_device.gbm);
   if (egl_renderer->edpy == EGL_NO_DISPLAY)
     {
       _cogl_set_error (error, COGL_WINSYS_ERROR,
@@ -354,7 +358,7 @@ _cogl_winsys_renderer_connect (CoglRenderer *renderer,
     goto fail;
 
   _cogl_poll_renderer_add_fd (renderer,
-                              kms_renderer->fd,
+                              kms_renderer->card_device.fd,
                               COGL_POLL_FD_EVENT_IN,
                               NULL, /* no prepare callback */
                               dispatch_kms_events,
@@ -566,7 +570,7 @@ setup_crtc_modes (CoglDisplay *display, int fb_id)
     {
       CoglKmsCrtc *crtc = l->data;
 
-      int ret = drmModeSetCrtc (kms_renderer->fd,
+      int ret = drmModeSetCrtc (kms_renderer->card_device.fd,
                                 crtc->id,
                                 fb_id, crtc->x, crtc->y,
                                 crtc->connectors, crtc->count,
@@ -598,7 +602,7 @@ flip_all_crtcs (CoglDisplay *display, CoglFlipKMS *flip, int fb_id)
 
       if (!kms_renderer->page_flips_not_supported)
         {
-          ret = drmModePageFlip (kms_renderer->fd,
+          ret = drmModePageFlip (kms_renderer->card_device.fd,
                                  crtc->id, fb_id,
                                  DRM_MODE_PAGE_FLIP_EVENT, flip);
           if (ret)
@@ -652,7 +656,7 @@ _cogl_winsys_egl_display_setup (CoglDisplay *display,
   kms_display = g_slice_new0 (CoglDisplayKMS);
   egl_display->platform = kms_display;
 
-  resources = drmModeGetResources (kms_renderer->fd);
+  resources = drmModeGetResources (kms_renderer->card_device.fd);
   if (!resources)
     {
       _cogl_set_error (error, COGL_WINSYS_ERROR,
@@ -662,7 +666,7 @@ _cogl_winsys_egl_display_setup (CoglDisplay *display,
     }
 
   output0 = find_output (0,
-                         kms_renderer->fd,
+                         kms_renderer->card_device.fd,
                          resources,
                          NULL,
                          0, /* n excluded connectors */
@@ -681,7 +685,7 @@ _cogl_winsys_egl_display_setup (CoglDisplay *display,
     {
       int exclude_connector = output0->connector->connector_id;
       output1 = find_output (1,
-                             kms_renderer->fd,
+                             kms_renderer->card_device.fd,
                              resources,
                              &exclude_connector,
                              1, /* n excluded connectors */
@@ -781,7 +785,7 @@ _cogl_winsys_egl_display_destroy (CoglDisplay *display)
   GList *l;
 
   for (l = kms_display->outputs; l; l = l->next)
-    output_free (kms_renderer->fd, l->data);
+    output_free (kms_renderer->card_device.fd, l->data);
   g_list_free (kms_display->outputs);
   kms_display->outputs = NULL;
 
@@ -804,7 +808,7 @@ _cogl_winsys_egl_context_created (CoglDisplay *display,
        COGL_EGL_WINSYS_FEATURE_SURFACELESS_CONTEXT) == 0)
     {
       kms_display->dummy_gbm_surface =
-        gbm_surface_create (kms_renderer->gbm,
+        gbm_surface_create (kms_renderer->card_device.gbm,
                             16, 16,
                             GBM_FORMAT_XRGB8888,
                             GBM_BO_USE_RENDERING);
@@ -912,7 +916,7 @@ _cogl_winsys_onscreen_swap_buffers_with_damage (CoglOnscreen *onscreen,
   stride = gbm_bo_get_stride (kms_onscreen->next_bo);
   handle = gbm_bo_get_handle (kms_onscreen->next_bo).u32;
 
-  if (drmModeAddFB (kms_renderer->fd,
+  if (drmModeAddFB (kms_renderer->card_device.fd,
                     kms_display->width,
                     kms_display->height,
                     24, /* depth */
@@ -944,7 +948,7 @@ _cogl_winsys_onscreen_swap_buffers_with_damage (CoglOnscreen *onscreen,
 
   if (flip->pending == 0)
     {
-      drmModeRmFB (kms_renderer->fd, kms_onscreen->next_fb_id);
+      drmModeRmFB (kms_renderer->card_device.fd, kms_onscreen->next_fb_id);
       gbm_surface_release_buffer (kms_onscreen->surface,
                                   kms_onscreen->next_bo);
       kms_onscreen->next_bo = NULL;
@@ -1019,7 +1023,7 @@ _cogl_winsys_onscreen_init (CoglOnscreen *onscreen,
   egl_onscreen->platform = kms_onscreen;
 
   kms_onscreen->surface =
-    gbm_surface_create (kms_renderer->gbm,
+    gbm_surface_create (kms_renderer->card_device.gbm,
                         kms_display->width,
                         kms_display->height,
                         GBM_FORMAT_XRGB8888,
@@ -1161,7 +1165,7 @@ cogl_kms_renderer_get_gbm (CoglRenderer *renderer)
     {
       CoglRendererEGL *egl_renderer = renderer->winsys;
       CoglRendererKMS *kms_renderer = egl_renderer->platform;
-      return kms_renderer->gbm;
+      return kms_renderer->card_device.gbm;
     }
     else
       return NULL;
@@ -1176,7 +1180,7 @@ cogl_kms_renderer_get_kms_fd (CoglRenderer *renderer)
     {
       CoglRendererEGL *egl_renderer = renderer->winsys;
       CoglRendererKMS *kms_renderer = egl_renderer->platform;
-      return kms_renderer->fd;
+      return kms_renderer->card_device.fd;
     }
   else
     return -1;
@@ -1220,7 +1224,7 @@ cogl_kms_display_set_layout (CoglDisplay *display,
 
       /* Need to drop the GBM surface and create a new one */
 
-      new_surface = gbm_surface_create (kms_renderer->gbm,
+      new_surface = gbm_surface_create (kms_renderer->card_device.gbm,
                                         width, height,
                                         GBM_FORMAT_XRGB8888,
                                         GBM_BO_USE_SCANOUT |