[src/trunk]: src/sys/external/bsd/drm2/drm Implement drm_new_set_master in dr...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e54541ba37ca
branches:  trunk
changeset: 835201:e54541ba37ca
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Mon Aug 27 07:53:52 2018 +0000

description:
Implement drm_new_set_master in drm_fops.c and use it.

diffstat:

 sys/external/bsd/drm2/drm/drm_fops.c |  114 ++++++++++++++++++++++++----------
 1 files changed, 81 insertions(+), 33 deletions(-)

diffs (147 lines):

diff -r 1814406541e9 -r e54541ba37ca sys/external/bsd/drm2/drm/drm_fops.c
--- a/sys/external/bsd/drm2/drm/drm_fops.c      Mon Aug 27 07:53:39 2018 +0000
+++ b/sys/external/bsd/drm2/drm/drm_fops.c      Mon Aug 27 07:53:52 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: drm_fops.c,v 1.9 2018/08/27 07:01:15 riastradh Exp $   */
+/*     $NetBSD: drm_fops.c,v 1.10 2018/08/27 07:53:52 riastradh Exp $  */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: drm_fops.c,v 1.9 2018/08/27 07:01:15 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: drm_fops.c,v 1.10 2018/08/27 07:53:52 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/select.h>
@@ -114,49 +114,97 @@
        return ret;
 }
 
+int
+drm_new_set_master(struct drm_device *dev, struct drm_file *file)
+{
+       struct drm_master *old_master;
+       int ret;
+
+       KASSERT(mutex_is_locked(&dev->master_mutex));
+       KASSERT(file->minor->type == DRM_MINOR_LEGACY);
+       KASSERT(file->minor->master == NULL);
+
+       file->minor->master = drm_master_create(file->minor);
+       if (file->minor->master == NULL) {
+               ret = -ENOMEM;
+               goto fail0;
+       }
+
+       /*
+        * Save the old master, to drop a reference later if all goes
+        * well, and get a reference to the new one.
+        */
+       old_master = file->master;
+       file->master = drm_master_get(file->minor->master);
+
+       /* Invoke the driver callbacks master_create and master_set.  */
+       if (dev->driver->master_create) {
+               ret = (*dev->driver->master_create)(dev, file->minor->master);
+               if (ret)
+                       goto fail1;
+       }
+
+       if (dev->driver->master_set) {
+               ret = (*dev->driver->master_set)(dev, file, true);
+               if (ret)
+                       goto fail1;
+       }
+
+       /*
+        * Mark ourselves as an authenticated master, and allowed to
+        * set a new master.
+        */
+       file->is_master = 1;
+       file->allowed_master = 1;
+       file->authenticated = 1;
+
+       /* If there was an old master, release it now.  */
+       if (old_master)
+               drm_master_put(&old_master);
+
+       /* Success!  */
+       return 0;
+
+fail1:
+       /* Release the master we just created.  */
+       drm_master_put(&file->minor->master);
+       KASSERT(file->minor->master == NULL);
+       /* Release the reference we just added in the file.  */
+       drm_master_put(&file->master);
+       KASSERT(file->master == NULL);
+       /* Restore the old master if there was one.  */
+       file->master = old_master;
+fail0: KASSERT(ret);
+       return ret;
+}
+
 static int
 drm_open_file_master(struct drm_file *file)
 {
        struct drm_device *const dev = file->minor->dev;
        int ret;
 
+       /* If this is not the legacy device, there are no masters.  */
+       if (file->minor->type != DRM_MINOR_LEGACY)
+               return 0;
+
        mutex_lock(&dev->master_mutex);
        if (file->minor->master != NULL) {
-               file->master = drm_master_get(file->minor->master);
-       } else {
-               file->minor->master = drm_master_create(file->minor);
-               if (file->minor->master == NULL) {
-                       ret = -ENOMEM;
-                       goto fail0;
-               }
-
-               file->is_master = 1;
+               /*
+                * If the minor already has a master, get a reference
+                * to it.
+                */
                file->master = drm_master_get(file->minor->master);
-               file->authenticated = 1;
-
-               if (dev->driver->master_create) {
-                       ret = (*dev->driver->master_create)(dev,
-                           file->minor->master);
-                       if (ret)
-                               goto fail1;
-               }
-
-               if (dev->driver->master_set) {
-                       ret = (*dev->driver->master_set)(dev, file, true);
-                       if (ret)
-                               goto fail1;
-               }
+               ret = 0;
+       } else {
+               /*
+                * Otherwise, automatically behave as though we had
+                * just done setmaster.
+                */
+               ret = drm_new_set_master(dev, file);
        }
        mutex_unlock(&dev->master_mutex);
 
-       /* Success!  */
-       return 0;
-
-fail1: mutex_unlock(&dev->master_mutex);
-       /* drm_master_put handles calling master_destroy for us.  */
-       drm_master_put(&file->minor->master);
-       drm_master_put(&file->master);
-fail0: KASSERT(ret);
        return ret;
 }