Debugfs APIs returns encoded error on failure instead of NULL and for drm primary/minor debugfs directories, we save the returned value in the dentry pointer and pass it on to drm drivers to further create debugfs files/directories. Error conditions are handled by debugfs APIs, so no need to check for NULL, as saved dentry pointers will either contain a valid pointer or an error code.
Also document this for future reference.
CC: Maarten Lankhorst maarten.lankhorst@linux.intel.com CC: Maxime Ripard mripard@kernel.org CC: Thomas Zimmermann tzimmermann@suse.de CC: David Airlie airlied@linux.ie CC: Daniel Vetter daniel@ffwll.ch
Signed-off-by: Nirmoy Das nirmoy.das@amd.com --- drivers/gpu/drm/drm_debugfs.c | 9 --------- drivers/gpu/drm/drm_drv.c | 1 + include/drm/drm_file.h | 28 ++++++++++++++++++++++++---- 3 files changed, 25 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index b0a826489488..0073854a4383 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -272,9 +272,6 @@ static void drm_debugfs_remove_all_files(struct drm_minor *minor)
void drm_debugfs_cleanup(struct drm_minor *minor) { - if (!minor->debugfs_root) - return; - drm_debugfs_remove_all_files(minor);
debugfs_remove_recursive(minor->debugfs_root); @@ -419,9 +416,6 @@ void drm_debugfs_connector_add(struct drm_connector *connector) struct drm_minor *minor = connector->dev->primary; struct dentry *root;
- if (!minor->debugfs_root) - return; - root = debugfs_create_dir(connector->name, minor->debugfs_root); connector->debugfs_entry = root;
@@ -440,9 +434,6 @@ void drm_debugfs_connector_add(struct drm_connector *connector)
void drm_debugfs_connector_remove(struct drm_connector *connector) { - if (!connector->debugfs_entry) - return; - debugfs_remove_recursive(connector->debugfs_entry);
connector->debugfs_entry = NULL; diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index 7a5097467ba5..918f302d9c43 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -64,6 +64,7 @@ static struct idr drm_minors_idr; */ static bool drm_core_init_complete;
+/* Do not deference this pointer as it will contain ERR_PTR on error. */ static struct dentry *drm_debugfs_root;
DEFINE_STATIC_SRCU(drm_unplug_srcu); diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h index a3acb7ac3550..3a30fc4d8905 100644 --- a/include/drm/drm_file.h +++ b/include/drm/drm_file.h @@ -69,15 +69,35 @@ enum drm_minor_type { */ struct drm_minor { /* private: */ - int index; /* Minor device number */ - int type; /* Control or render */ - struct device *kdev; /* Linux device */ + /** @index: minor device number. */ + int index; + + /** @type: minor device type: primary, control, render. */ + int type; + + /** @kdev: Linux device pointer. */ + struct device *kdev; + + /** @dev: drm device pointer. */ struct drm_device *dev;
+ + /** @debugfs_root: + * + * Dentry for /sys/kernel/debug/dri/@index debugfs dir. Do not + * deference this pointer as it will contain ERR_PTR on error. + */ struct dentry *debugfs_root;
+ /** @debugfs_list: + * + * A list to keep track of debugfs dentries created using + * drm_debugfs_create_files() by drm drivers. + */ struct list_head debugfs_list; - struct mutex debugfs_lock; /* Protects debugfs_list. */ + + /** @debugfs_lock: Protects debugfs_list. */ + struct mutex debugfs_lock; };
/** -- 2.32.0