summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorChris Wilson <chris@chris-wilson.co.uk>2017-02-02 09:36:32 +0000
committerDaniel Vetter <daniel.vetter@ffwll.ch>2017-02-02 15:58:06 +0100
commitf30c92576af4bb155d26429540aae95e0a256ce2 (patch)
treec70d80092e2d9d19a937f1b862f14be0a0c95cbe
parent8aaacbc0e5c729baa1dbae26f77755c96a23096e (diff)
downloadlinux-stable-f30c92576af4bb155d26429540aae95e0a256ce2.tar.gz
linux-stable-f30c92576af4bb155d26429540aae95e0a256ce2.tar.bz2
linux-stable-f30c92576af4bb155d26429540aae95e0a256ce2.zip
drm: Provide a driver hook for drm_dev_release()
Some state is coupled into the device lifetime outside of the load/unload timeframe and requires teardown during final unreference from drm_dev_release(). For example, dmabufs hold both a device and module reference and may live longer than expected (i.e. the current pattern of the driver tearing down its state and then releasing a reference to the drm device) and yet touch driver private state when destroyed. v2: Export drm_dev_fini() and move the responsibility for finalizing the drm_device and freeing it to the release callback. (If no callback is provided, the core will call drm_dev_fini() and kfree(dev) as before.) v3: Remember to add drm_dev_fini() to drm_drv.h v4: Tidy language for kerneldoc v5: Cross reference from drm_dev_init() to note that driver->release() allows for arbitrary embedding. v6: Refer to driver data rather than driver state, as state is now becoming associated with the struct drm_atomic_state and friends. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> [danvet: Use the proper reference for struct members, which is &drm_driver.release.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20170202093632.31017-1-chris@chris-wilson.co.uk
-rw-r--r--drivers/gpu/drm/drm_drv.c65
-rw-r--r--include/drm/drm_drv.h13
2 files changed, 58 insertions, 20 deletions
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 6cbd67f4fbc5..45ce224688ce 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -465,7 +465,10 @@ static void drm_fs_inode_free(struct inode *inode)
* that do embed &struct drm_device it must be placed first in the overall
* structure, and the overall structure must be allocated using kmalloc(): The
* drm core's release function unconditionally calls kfree() on the @dev pointer
- * when the final reference is released.
+ * when the final reference is released. To override this behaviour, and so
+ * allow embedding of the drm_device inside the driver's device struct at an
+ * arbitrary offset, you must supply a &drm_driver.release callback and control
+ * the finalization explicitly.
*
* RETURNS:
* 0 on success, or error code on failure.
@@ -553,6 +556,41 @@ err_free:
EXPORT_SYMBOL(drm_dev_init);
/**
+ * drm_dev_fini - Finalize a dead DRM device
+ * @dev: DRM device
+ *
+ * Finalize a dead DRM device. This is the converse to drm_dev_init() and
+ * frees up all data allocated by it. All driver private data should be
+ * finalized first. Note that this function does not free the @dev, that is
+ * left to the caller.
+ *
+ * The ref-count of @dev must be zero, and drm_dev_fini() should only be called
+ * from a &drm_driver.release callback.
+ */
+void drm_dev_fini(struct drm_device *dev)
+{
+ drm_vblank_cleanup(dev);
+
+ if (drm_core_check_feature(dev, DRIVER_GEM))
+ drm_gem_destroy(dev);
+
+ drm_legacy_ctxbitmap_cleanup(dev);
+ drm_ht_remove(&dev->map_hash);
+ drm_fs_inode_free(dev->anon_inode);
+
+ drm_minor_free(dev, DRM_MINOR_PRIMARY);
+ drm_minor_free(dev, DRM_MINOR_RENDER);
+ drm_minor_free(dev, DRM_MINOR_CONTROL);
+
+ mutex_destroy(&dev->master_mutex);
+ mutex_destroy(&dev->ctxlist_mutex);
+ mutex_destroy(&dev->filelist_mutex);
+ mutex_destroy(&dev->struct_mutex);
+ kfree(dev->unique);
+}
+EXPORT_SYMBOL(drm_dev_fini);
+
+/**
* drm_dev_alloc - Allocate new DRM device
* @driver: DRM driver to allocate device for
* @parent: Parent device object
@@ -598,25 +636,12 @@ static void drm_dev_release(struct kref *ref)
{
struct drm_device *dev = container_of(ref, struct drm_device, ref);
- drm_vblank_cleanup(dev);
-
- if (drm_core_check_feature(dev, DRIVER_GEM))
- drm_gem_destroy(dev);
-
- drm_legacy_ctxbitmap_cleanup(dev);
- drm_ht_remove(&dev->map_hash);
- drm_fs_inode_free(dev->anon_inode);
-
- drm_minor_free(dev, DRM_MINOR_PRIMARY);
- drm_minor_free(dev, DRM_MINOR_RENDER);
- drm_minor_free(dev, DRM_MINOR_CONTROL);
-
- mutex_destroy(&dev->master_mutex);
- mutex_destroy(&dev->ctxlist_mutex);
- mutex_destroy(&dev->filelist_mutex);
- mutex_destroy(&dev->struct_mutex);
- kfree(dev->unique);
- kfree(dev);
+ if (dev->driver->release) {
+ dev->driver->release(dev);
+ } else {
+ drm_dev_fini(dev);
+ kfree(dev);
+ }
}
/**
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 732e85652d1e..5699f42195fe 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -102,6 +102,17 @@ struct drm_driver {
*
*/
void (*unload) (struct drm_device *);
+
+ /**
+ * @release:
+ *
+ * Optional callback for destroying device data after the final
+ * reference is released, i.e. the device is being destroyed. Drivers
+ * using this callback are responsible for calling drm_dev_fini()
+ * to finalize the device and then freeing the struct themselves.
+ */
+ void (*release) (struct drm_device *);
+
int (*set_busid)(struct drm_device *dev, struct drm_master *master);
/**
@@ -437,6 +448,8 @@ extern unsigned int drm_debug;
int drm_dev_init(struct drm_device *dev,
struct drm_driver *driver,
struct device *parent);
+void drm_dev_fini(struct drm_device *dev);
+
struct drm_device *drm_dev_alloc(struct drm_driver *driver,
struct device *parent);
int drm_dev_register(struct drm_device *dev, unsigned long flags);