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path: root/drivers/gpu/drm/drm_drv.c
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Diffstat (limited to 'drivers/gpu/drm/drm_drv.c')
-rw-r--r--drivers/gpu/drm/drm_drv.c56
1 files changed, 41 insertions, 15 deletions
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 37b8ad3e30d8..be38ac7050d4 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -63,6 +63,15 @@ module_param_named(debug, drm_debug, int, 0600);
static DEFINE_SPINLOCK(drm_minor_lock);
static struct idr drm_minors_idr;
+/*
+ * If the drm core fails to init for whatever reason,
+ * we should prevent any drivers from registering with it.
+ * It's best to check this at drm_dev_init(), as some drivers
+ * prefer to embed struct drm_device into their own device
+ * structure and call drm_dev_init() themselves.
+ */
+static bool drm_core_init_complete = false;
+
static struct dentry *drm_debugfs_root;
#define DRM_PRINTK_FMT "[" DRM_NAME ":%s]%s %pV"
@@ -282,7 +291,7 @@ struct drm_minor *drm_minor_acquire(unsigned int minor_id)
if (!minor) {
return ERR_PTR(-ENODEV);
- } else if (drm_device_is_unplugged(minor->dev)) {
+ } else if (drm_dev_is_unplugged(minor->dev)) {
drm_dev_unref(minor->dev);
return ERR_PTR(-ENODEV);
}
@@ -355,26 +364,32 @@ void drm_put_dev(struct drm_device *dev)
}
EXPORT_SYMBOL(drm_put_dev);
-void drm_unplug_dev(struct drm_device *dev)
+static void drm_device_set_unplugged(struct drm_device *dev)
{
- /* for a USB device */
- if (drm_core_check_feature(dev, DRIVER_MODESET))
- drm_modeset_unregister_all(dev);
+ smp_wmb();
+ atomic_set(&dev->unplugged, 1);
+}
- drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
- drm_minor_unregister(dev, DRM_MINOR_RENDER);
- drm_minor_unregister(dev, DRM_MINOR_CONTROL);
+/**
+ * drm_dev_unplug - unplug a DRM device
+ * @dev: DRM device
+ *
+ * This unplugs a hotpluggable DRM device, which makes it inaccessible to
+ * userspace operations. Entry-points can use drm_dev_is_unplugged(). This
+ * essentially unregisters the device like drm_dev_unregister(), but can be
+ * called while there are still open users of @dev.
+ */
+void drm_dev_unplug(struct drm_device *dev)
+{
+ drm_dev_unregister(dev);
mutex_lock(&drm_global_mutex);
-
drm_device_set_unplugged(dev);
-
- if (dev->open_count == 0) {
- drm_put_dev(dev);
- }
+ if (dev->open_count == 0)
+ drm_dev_unref(dev);
mutex_unlock(&drm_global_mutex);
}
-EXPORT_SYMBOL(drm_unplug_dev);
+EXPORT_SYMBOL(drm_dev_unplug);
/*
* DRM internal mount
@@ -484,6 +499,11 @@ int drm_dev_init(struct drm_device *dev,
{
int ret;
+ if (!drm_core_init_complete) {
+ DRM_ERROR("DRM core is not initialized\n");
+ return -ENODEV;
+ }
+
kref_init(&dev->ref);
dev->dev = parent;
dev->driver = driver;
@@ -821,6 +841,9 @@ EXPORT_SYMBOL(drm_dev_register);
* drm_dev_register() but does not deallocate the device. The caller must call
* drm_dev_unref() to drop their final reference.
*
+ * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
+ * which can be called while there are still open users of @dev.
+ *
* This should be called first in the device teardown code to make sure
* userspace can't access the device instance any more.
*/
@@ -828,7 +851,8 @@ void drm_dev_unregister(struct drm_device *dev)
{
struct drm_map_list *r_list, *list_temp;
- drm_lastclose(dev);
+ if (drm_core_check_feature(dev, DRIVER_LEGACY))
+ drm_lastclose(dev);
dev->registered = false;
@@ -966,6 +990,8 @@ static int __init drm_core_init(void)
if (ret < 0)
goto error;
+ drm_core_init_complete = true;
+
DRM_DEBUG("Initialized\n");
return 0;