[PATCH v2 2/7] drm/drv: Add drmm managed registration helper for dmem cgroups.

From: Maarten Lankhorst
Date: Wed Dec 04 2024 - 09:17:25 EST


From: Maxime Ripard <mripard@xxxxxxxxxx>

Drivers will need to register dmem regions at probe time, so let's
give them a drm-managed helper.

Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
Signed-off-by: Maarten Lankhorst <dev@xxxxxxxxxxxx>
---
drivers/gpu/drm/drm_drv.c | 32 ++++++++++++++++++++++++++++++++
include/drm/drm_drv.h | 5 +++++
2 files changed, 37 insertions(+)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index c2c172eb25df7..3cf440eee8a2a 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -26,6 +26,7 @@
* DEALINGS IN THE SOFTWARE.
*/

+#include <linux/cgroup_dmem.h>
#include <linux/debugfs.h>
#include <linux/fs.h>
#include <linux/module.h>
@@ -820,6 +821,37 @@ void drm_dev_put(struct drm_device *dev)
}
EXPORT_SYMBOL(drm_dev_put);

+static void drmm_cg_unregister_region(struct drm_device *dev, void *arg)
+{
+ dmem_cgroup_unregister_region(arg);
+}
+
+/**
+ * drmm_cgroup_register_region - Register a region of a DRM device to cgroups
+ * @dev: device for region
+ * @region_name: Region name for registering
+ * @size: Size of region in bytes
+ *
+ * This decreases the ref-count of @dev by one. The device is destroyed if the
+ * ref-count drops to zero.
+ */
+struct dmem_cgroup_region *drmm_cgroup_register_region(struct drm_device *dev, const char *region_name, u64 size)
+{
+ struct dmem_cgroup_region *region;
+ int ret;
+
+ region = dmem_cgroup_register_region(size, "drm/%s/%s", dev->unique, region_name);
+ if (IS_ERR_OR_NULL(region))
+ return region;
+
+ ret = drmm_add_action_or_reset(dev, drmm_cg_unregister_region, region);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return region;
+}
+EXPORT_SYMBOL_GPL(drmm_cgroup_register_region);
+
static int create_compat_control_link(struct drm_device *dev)
{
struct drm_minor *minor;
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 1bbbcb8e2d231..7dd49d9ab5058 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -34,6 +34,7 @@

#include <drm/drm_device.h>

+struct dmem_cgroup_region;
struct drm_fb_helper;
struct drm_fb_helper_surface_size;
struct drm_file;
@@ -438,6 +439,10 @@ void *__devm_drm_dev_alloc(struct device *parent,
const struct drm_driver *driver,
size_t size, size_t offset);

+struct dmem_cgroup_region *
+drmm_cgroup_register_region(struct drm_device *dev,
+ const char *region_name, u64 size);
+
/**
* devm_drm_dev_alloc - Resource managed allocation of a &drm_device instance
* @parent: Parent device object
--
2.43.0