[Intel-gfx] [PATCH 44/44] drm/managed: Cleanup of unused functions and polishing docs
Daniel Vetter
daniel.vetter at ffwll.ch
Fri Apr 3 13:58:28 UTC 2020
Following functions are only used internally, not by drivers:
- drm_dev_init
- devm_drm_dev_init
- drmm_add_final_kfree
Also, now that we have a very slick and polished way to allocate a
drm_device with devm_drm_dev_alloc, update all the docs to reflect the
new reality. Mostly this consists of deleting old and misleading
hints. Two main ones:
- it is no longer required that the drm_device base class is first in
the structure. devm_drm_dev_alloc can cope with it being anywhere
- obviously embedded no needs devm_drm_dev_alloc
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
.../driver-api/driver-model/devres.rst | 2 +-
drivers/gpu/drm/drm_drv.c | 119 ++++--------------
drivers/gpu/drm/drm_internal.h | 1 +
drivers/gpu/drm/drm_managed.c | 15 +--
include/drm/drm_device.h | 2 +-
include/drm/drm_drv.h | 20 +--
6 files changed, 34 insertions(+), 125 deletions(-)
diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 46c13780994c..74a4a3fa8c52 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -263,7 +263,7 @@ DMA
dmam_pool_destroy()
DRM
- devm_drm_dev_init()
+ devm_drm_dev_alloc()
GPIO
devm_gpiod_get()
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 9e60b784b3ac..64e20c630aa7 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -240,13 +240,13 @@ void drm_minor_release(struct drm_minor *minor)
* DOC: driver instance overview
*
* A device instance for a drm driver is represented by &struct drm_device. This
- * is initialized with drm_dev_init(), usually from bus-specific ->probe()
- * callbacks implemented by the driver. The driver then needs to initialize all
- * the various subsystems for the drm device like memory management, vblank
- * handling, modesetting support and intial output configuration plus obviously
- * initialize all the corresponding hardware bits. Finally when everything is up
- * and running and ready for userspace the device instance can be published
- * using drm_dev_register().
+ * is allocated and initialized with devm_drm_dev_alloc(), usually from
+ * bus-specific ->probe() callbacks implemented by the driver. The driver then
+ * needs to initialize all the various subsystems for the drm device like memory
+ * management, vblank handling, modesetting support and intial output
+ * configuration plus obviously initialize all the corresponding hardware bits.
+ * Finally when everything is up and running and ready for userspace the device
+ * instance can be published using drm_dev_register().
*
* There is also deprecated support for initalizing device instances using
* bus-specific helpers and the &drm_driver.load callback. But due to
@@ -274,7 +274,7 @@ void drm_minor_release(struct drm_minor *minor)
*
* The following example shows a typical structure of a DRM display driver.
* The example focus on the probe() function and the other functions that is
- * almost always present and serves as a demonstration of devm_drm_dev_init().
+ * almost always present and serves as a demonstration of devm_drm_dev_alloc().
*
* .. code-block:: c
*
@@ -294,22 +294,12 @@ void drm_minor_release(struct drm_minor *minor)
* struct drm_device *drm;
* int ret;
*
- * // devm_kzalloc() can't be used here because the drm_device '
- * // lifetime can exceed the device lifetime if driver unbind
- * // happens when userspace still has open file descriptors.
- * priv = kzalloc(sizeof(*priv), GFP_KERNEL);
- * if (!priv)
- * return -ENOMEM;
- *
+ * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver,
+ * struct driver_device, drm);
+ * if (IS_ERR(priv))
+ * return PTR_ERR(priv);
* drm = &priv->drm;
*
- * ret = devm_drm_dev_init(&pdev->dev, drm, &driver_drm_driver);
- * if (ret) {
- * kfree(priv);
- * return ret;
- * }
- * drmm_add_final_kfree(drm, priv);
- *
* ret = drmm_mode_config_init(drm);
* if (ret)
* return ret;
@@ -550,9 +540,9 @@ static void drm_fs_inode_free(struct inode *inode)
* following guidelines apply:
*
* - The entire device initialization procedure should be run from the
- * &component_master_ops.master_bind callback, starting with drm_dev_init(),
- * then binding all components with component_bind_all() and finishing with
- * drm_dev_register().
+ * &component_master_ops.master_bind callback, starting with
+ * devm_drm_dev_alloc(), then binding all components with
+ * component_bind_all() and finishing with drm_dev_register().
*
* - The opaque pointer passed to all components through component_bind_all()
* should point at &struct drm_device of the device instance, not some driver
@@ -583,43 +573,9 @@ static void drm_dev_init_release(struct drm_device *dev, void *res)
drm_legacy_destroy_members(dev);
}
-/**
- * drm_dev_init - Initialise new DRM device
- * @dev: DRM device
- * @driver: DRM driver
- * @parent: Parent device object
- *
- * Initialize a new DRM device. No device registration is done.
- * Call drm_dev_register() to advertice the device to user space and register it
- * with other core subsystems. This should be done last in the device
- * initialization sequence to make sure userspace can't access an inconsistent
- * state.
- *
- * The initial ref-count of the object is 1. Use drm_dev_get() and
- * drm_dev_put() to take and drop further ref-counts.
- *
- * It is recommended that drivers embed &struct drm_device into their own device
- * structure.
- *
- * Drivers that do not want to allocate their own device struct
- * embedding &struct drm_device can call drm_dev_alloc() instead. For drivers
- * 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. 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.
- *
- * Note that drivers must call drmm_add_final_kfree() after this function has
- * completed successfully.
- *
- * RETURNS:
- * 0 on success, or error code on failure.
- */
-int drm_dev_init(struct drm_device *dev,
- struct drm_driver *driver,
- struct device *parent)
+static int drm_dev_init(struct drm_device *dev,
+ struct drm_driver *driver,
+ struct device *parent)
{
int ret;
@@ -699,31 +655,15 @@ int drm_dev_init(struct drm_device *dev,
return ret;
}
-EXPORT_SYMBOL(drm_dev_init);
static void devm_drm_dev_init_release(void *data)
{
drm_dev_put(data);
}
-/**
- * devm_drm_dev_init - Resource managed drm_dev_init()
- * @parent: Parent device object
- * @dev: DRM device
- * @driver: DRM driver
- *
- * Managed drm_dev_init(). The DRM device initialized with this function is
- * automatically put on driver detach using drm_dev_put().
- *
- * Note that drivers must call drmm_add_final_kfree() after this function has
- * completed successfully.
- *
- * RETURNS:
- * 0 on success, or error code on failure.
- */
-int devm_drm_dev_init(struct device *parent,
- struct drm_device *dev,
- struct drm_driver *driver)
+static int devm_drm_dev_init(struct device *parent,
+ struct drm_device *dev,
+ struct drm_driver *driver)
{
int ret;
@@ -737,7 +677,6 @@ int devm_drm_dev_init(struct device *parent,
return ret;
}
-EXPORT_SYMBOL(devm_drm_dev_init);
void* __devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver,
size_t size, size_t offset)
@@ -767,19 +706,9 @@ EXPORT_SYMBOL(__devm_drm_dev_alloc);
* @driver: DRM driver to allocate device for
* @parent: Parent device object
*
- * Allocate and initialize a new DRM device. No device registration is done.
- * Call drm_dev_register() to advertice the device to user space and register it
- * with other core subsystems. This should be done last in the device
- * initialization sequence to make sure userspace can't access an inconsistent
- * state.
- *
- * The initial ref-count of the object is 1. Use drm_dev_get() and
- * drm_dev_put() to take and drop further ref-counts.
- *
- * Note that for purely virtual devices @parent can be NULL.
- *
- * Drivers that wish to subclass or embed &struct drm_device into their
- * own struct should look at using drm_dev_init() instead.
+ * This is the deprecated version of devm_drm_dev_alloc(), which doesn not support
+ * subclassing through embedding the struct &drm_device in a driver private
+ * structure, and which does not support automatic cleanup through devres.
*
* RETURNS:
* Pointer to new DRM device, or ERR_PTR on failure.
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index 2470a352730b..79f11d3c525e 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -91,6 +91,7 @@ void drm_minor_release(struct drm_minor *minor);
/* drm_managed.c */
void drm_managed_release(struct drm_device *dev);
+void drmm_add_final_kfree(struct drm_device *dev, void *container);
/* drm_vblank.c */
void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe);
diff --git a/drivers/gpu/drm/drm_managed.c b/drivers/gpu/drm/drm_managed.c
index 9cebfe370a65..a2a0c5b7ab78 100644
--- a/drivers/gpu/drm/drm_managed.c
+++ b/drivers/gpu/drm/drm_managed.c
@@ -25,7 +25,7 @@
* be done directly with drmm_kmalloc() and the related functions. Everything
* will be released on the final drm_dev_put() in reverse order of how the
* release actions have been added and memory has been allocated since driver
- * loading started with drm_dev_init().
+ * loading started with devm_drm_dev_alloc().
*
* Note that release actions and managed memory can also be added and removed
* during the lifetime of the driver, all the functions are fully concurrent
@@ -123,18 +123,6 @@ static void add_dr(struct drm_device *dev, struct drmres *dr)
dr, dr->node.name, (unsigned long) dr->node.size);
}
-/**
- * drmm_add_final_kfree - add release action for the final kfree()
- * @dev: DRM device
- * @container: pointer to the kmalloc allocation containing @dev
- *
- * Since the allocation containing the struct &drm_device must be allocated
- * before it can be initialized with drm_dev_init() there's no way to allocate
- * that memory with drmm_kmalloc(). To side-step this chicken-egg problem the
- * pointer for this final kfree() must be specified by calling this function. It
- * will be released in the final drm_dev_put() for @dev, after all other release
- * actions installed through drmm_add_action() have been processed.
- */
void drmm_add_final_kfree(struct drm_device *dev, void *container)
{
WARN_ON(dev->managed.final_kfree);
@@ -142,7 +130,6 @@ void drmm_add_final_kfree(struct drm_device *dev, void *container)
WARN_ON(dev + 1 > (struct drm_device *) (container + ksize(container)));
dev->managed.final_kfree = container;
}
-EXPORT_SYMBOL(drmm_add_final_kfree);
int __drmm_add_action(struct drm_device *dev,
drmres_release_t action,
diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index a55874db9dd4..ee9e20ce9b85 100644
--- a/include/drm/drm_device.h
+++ b/include/drm/drm_device.h
@@ -92,7 +92,7 @@ struct drm_device {
* NULL.
*
* Instead of using this pointer it is recommended that drivers use
- * drm_dev_init() and embed struct &drm_device in their larger
+ * devm_drm_dev_alloc() and embed struct &drm_device in their larger
* per-device structure.
*/
void *dev_private;
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 26776be5a21e..2806cc5eae3a 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -163,13 +163,12 @@ struct drm_driver {
/**
* @load:
*
- * Backward-compatible driver callback to complete
- * initialization steps after the driver is registered. For
- * this reason, may suffer from race conditions and its use is
- * deprecated for new drivers. It is therefore only supported
- * for existing drivers not yet converted to the new scheme.
- * See drm_dev_init() and drm_dev_register() for proper and
- * race-free way to set up a &struct drm_device.
+ * Backward-compatible driver callback to complete initialization steps
+ * after the driver is registered. For this reason, may suffer from
+ * race conditions and its use is deprecated for new drivers. It is
+ * therefore only supported for existing drivers not yet converted to
+ * the new scheme. See devm_drm_dev_alloc() and drm_dev_register() for
+ * proper and race-free way to set up a &struct drm_device.
*
* This is deprecated, do not use!
*
@@ -619,13 +618,6 @@ struct drm_driver {
int dev_priv_size;
};
-int drm_dev_init(struct drm_device *dev,
- struct drm_driver *driver,
- struct device *parent);
-int devm_drm_dev_init(struct device *parent,
- struct drm_device *dev,
- struct drm_driver *driver);
-
void* __devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver,
size_t size, size_t offset);
--
2.25.1
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