76  * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
78  * of the device-driver, different interfaces are registered.
80  * Minors can be accessed via dev->$minor_name. This pointer is either
82  * valid. This means, DRM minors have the same life-time as the underlying
84  * registered and unregistered dynamically according to device-state.
96 		return ERR_PTR(-EOPNOTSUPP);  in drm_minor_get_xa()
104 		return &dev->primary;  in drm_minor_get_slot()
106 		return &dev->render;  in drm_minor_get_slot()
108 		return &dev->accel;  in drm_minor_get_slot()
118 	WARN_ON(dev != minor->dev);  in drm_minor_alloc_release()
120 	put_device(minor->kdev);  in drm_minor_alloc_release()
122 	xa_erase(drm_minor_get_xa(minor->type), minor->index);  in drm_minor_alloc_release()
127  * minor allocation scheme where minors 0-63 are primary nodes, 64-127 are control nodes,
128  * and 128-191 are render nodes.
129  * After reaching the limit, we're allocating minors dynamically - first-come, first-serve.
130  * Accel nodes are using a distinct major, so the minors are allocated in continuous 0-MAX
137 #define DRM_EXTENDED_MINOR_LIMIT XA_LIMIT(192, (1 << MINORBITS) - 1)
146 		return -ENOMEM;  in drm_minor_alloc()
148 	minor->type = type;  in drm_minor_alloc()
149 	minor->dev = dev;  in drm_minor_alloc()
151 	r = xa_alloc(drm_minor_get_xa(type), &minor->index,  in drm_minor_alloc()
153 	if (r == -EBUSY && (type == DRM_MINOR_PRIMARY || type == DRM_MINOR_RENDER))  in drm_minor_alloc()
154 		r = xa_alloc(&drm_minors_xa, &minor->index,  in drm_minor_alloc()
163 	minor->kdev = drm_sysfs_minor_alloc(minor);  in drm_minor_alloc()
164 	if (IS_ERR(minor->kdev))  in drm_minor_alloc()
165 		return PTR_ERR(minor->kdev);  in drm_minor_alloc()
183 	if (minor->type != DRM_MINOR_ACCEL) {  in drm_minor_register()
184 		ret = drm_debugfs_register(minor, minor->index,  in drm_minor_register()
192 	ret = device_add(minor->kdev);  in drm_minor_register()
197 	entry = xa_store(drm_minor_get_xa(type), minor->index, minor, GFP_KERNEL);  in drm_minor_register()
204 	DRM_DEBUG("new minor registered %d\n", minor->index);  in drm_minor_register()
217 	if (!minor || !device_is_registered(minor->kdev))  in drm_minor_unregister()
221 	xa_store(drm_minor_get_xa(type), minor->index, NULL, GFP_KERNEL);  in drm_minor_unregister()
223 	device_del(minor->kdev);  in drm_minor_unregister()
224 	dev_set_drvdata(minor->kdev, NULL); /* safety belt */  in drm_minor_unregister()
229  * Looks up the given minor-ID and returns the respective DRM-minor object. The
230  * refence-count of the underlying device is increased so you must release this
234  * minor->dev pointer will stay valid! However, the device may get unplugged and
244 		drm_dev_get(minor->dev);  in drm_minor_acquire()
248 		return ERR_PTR(-ENODEV);  in drm_minor_acquire()
249 	} else if (drm_dev_is_unplugged(minor->dev)) {  in drm_minor_acquire()
250 		drm_dev_put(minor->dev);  in drm_minor_acquire()
251 		return ERR_PTR(-ENODEV);  in drm_minor_acquire()
259 	drm_dev_put(minor->dev);  in drm_minor_release()
267  * bus-specific ->probe() callbacks implemented by the driver. The driver then
275  * bus-specific helpers and the &drm_driver.load callback. But due to
276  * backwards-compatibility needs the device instance have to be published too
302  * .. code-block:: c
320  *		priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver,
324  *		drm = &priv->drm;
330  *		priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL);
331  *		if (!priv->userspace_facing)
332  *			return -ENOMEM;
334  *		priv->pclk = devm_clk_get(dev, "PCLK");
335  *		if (IS_ERR(priv->pclk))
336  *			return PTR_ERR(priv->pclk);
408  * drm_put_dev - Unregister and release a DRM device
436  * drm_dev_enter - Enter device critical section
451 	if (dev->unplugged) {  in drm_dev_enter()
461  * drm_dev_exit - Exit device critical section
474  * drm_dev_unplug - unplug a DRM device
478  * userspace operations. Entry-points can use drm_dev_enter() and
487 	 * the new value of ->unplugged, and any critical section which might  in drm_dev_unplug()
488 	 * still have seen the old value of ->unplugged is guaranteed to have  in drm_dev_unplug()
491 	dev->unplugged = true;  in drm_dev_unplug()
497 	unmap_mapping_range(dev->anon_inode->i_mapping, 0, 0, 1);  in drm_dev_unplug()
504  * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
505  * stand-alone address_space objects, so we need an underlying inode. As there
507  * VFS mount-point.
513  * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
514  * between multiple inode-users. You could, technically, call
524 	return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM;  in drm_fs_init_fs_context()
545 	inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);  in drm_fs_inode_new()
568  *  - The entire device initialization procedure should be run from the
573  *  - The opaque pointer passed to all components through component_bind_all()
577  *  - The component helper fills the niche where further standardization of
587 	drm_fs_inode_free(dev->anon_inode);  in drm_dev_init_release()
589 	put_device(dev->dev);  in drm_dev_init_release()
590 	/* Prevent use-after-free in drm_managed_release when debugging is  in drm_dev_init_release()
592 	dev->dev = NULL;  in drm_dev_init_release()
593 	mutex_destroy(&dev->master_mutex);  in drm_dev_init_release()
594 	mutex_destroy(&dev->clientlist_mutex);  in drm_dev_init_release()
595 	mutex_destroy(&dev->filelist_mutex);  in drm_dev_init_release()
596 	mutex_destroy(&dev->struct_mutex);  in drm_dev_init_release()
608 		return -ENODEV;  in drm_dev_init()
612 		return -EINVAL;  in drm_dev_init()
614 	kref_init(&dev->ref);  in drm_dev_init()
615 	dev->dev = get_device(parent);  in drm_dev_init()
616 	dev->driver = driver;  in drm_dev_init()
618 	INIT_LIST_HEAD(&dev->managed.resources);  in drm_dev_init()
619 	spin_lock_init(&dev->managed.lock);  in drm_dev_init()
621 	/* no per-device feature limits by default */  in drm_dev_init()
622 	dev->driver_features = ~0u;  in drm_dev_init()
628 		return -EINVAL;  in drm_dev_init()
631 	INIT_LIST_HEAD(&dev->filelist);  in drm_dev_init()
632 	INIT_LIST_HEAD(&dev->filelist_internal);  in drm_dev_init()
633 	INIT_LIST_HEAD(&dev->clientlist);  in drm_dev_init()
634 	INIT_LIST_HEAD(&dev->vblank_event_list);  in drm_dev_init()
636 	spin_lock_init(&dev->event_lock);  in drm_dev_init()
637 	mutex_init(&dev->struct_mutex);  in drm_dev_init()
638 	mutex_init(&dev->filelist_mutex);  in drm_dev_init()
639 	mutex_init(&dev->clientlist_mutex);  in drm_dev_init()
640 	mutex_init(&dev->master_mutex);  in drm_dev_init()
641 	raw_spin_lock_init(&dev->mode_config.panic_lock);  in drm_dev_init()
654 	dev->anon_inode = inode;  in drm_dev_init()
680 	dev->unique = drmm_kstrdup(dev, dev_name(parent), GFP_KERNEL);  in drm_dev_init()
681 	if (!dev->unique) {  in drm_dev_init()
682 		ret = -ENOMEM;  in drm_dev_init()
728 		return ERR_PTR(-ENOMEM);  in __devm_drm_dev_alloc()
743  * drm_dev_alloc - Allocate new DRM device
762 		return ERR_PTR(-ENOMEM);  in drm_dev_alloc()
783 	if (dev->driver->release)  in drm_dev_release()
784 		dev->driver->release(dev);  in drm_dev_release()
788 	kfree(dev->managed.final_kfree);  in drm_dev_release()
792  * drm_dev_get - Take reference of a DRM device
795  * This increases the ref-count of @dev by one. You *must* already own a
806 		kref_get(&dev->ref);  in drm_dev_get()
811  * drm_dev_put - Drop reference of a DRM device
814  * This decreases the ref-count of @dev by one. The device is destroyed if the
815  * ref-count drops to zero.
820 		kref_put(&dev->ref, drm_dev_release);  in drm_dev_put()
830  * drmm_cgroup_register_region - Register a region of a DRM device to cgroups
835  * This decreases the ref-count of @dev by one. The device is destroyed if the
836  * ref-count drops to zero.
843 	region = dmem_cgroup_register_region(size, "drm/%s/%s", dev->unique, region_name);  in drmm_cgroup_register_region()
875 	 * 64-127.  in create_compat_control_link()
877 	name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);  in create_compat_control_link()
879 		return -ENOMEM;  in create_compat_control_link()
881 	ret = sysfs_create_link(minor->kdev->kobj.parent,  in create_compat_control_link()
882 				&minor->kdev->kobj,  in create_compat_control_link()
902 	name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);  in remove_compat_control_link()
906 	sysfs_remove_link(minor->kdev->kobj.parent, name);  in remove_compat_control_link()
912  * drm_dev_register - Register DRM device
916  * Register the DRM device @dev with the system, advertise device to user-space
933 	const struct drm_driver *driver = dev->driver;  in drm_dev_register()
936 	if (!driver->load)  in drm_dev_register()
939 	WARN_ON(!dev->managed.final_kfree);  in drm_dev_register()
965 	dev->registered = true;  in drm_dev_register()
967 	if (driver->load) {  in drm_dev_register()
968 		ret = driver->load(dev, flags);  in drm_dev_register()
981 		 driver->name, driver->major, driver->minor,  in drm_dev_register()
982 		 driver->patchlevel,  in drm_dev_register()
983 		 dev->dev ? dev_name(dev->dev) : "virtual device",  in drm_dev_register()
984 		 dev->primary ? dev->primary->index : dev->accel->index);  in drm_dev_register()
989 	if (dev->driver->unload)  in drm_dev_register()
990 		dev->driver->unload(dev);  in drm_dev_register()
1004  * drm_dev_unregister - Unregister DRM device
1021 	dev->registered = false;  in drm_dev_unregister()
1030 	if (dev->driver->unload)  in drm_dev_unregister()
1031 		dev->driver->unload(dev);  in drm_dev_unregister()
1047  *  - The "DRM-Global" key/value database
1048  *  - Global ID management for connectors
1049  *  - DRM major number allocation
1050  *  - DRM minor management
1051  *  - DRM sysfs class
1052  *  - DRM debugfs root
1054  * Furthermore, the DRM core provides dynamic char-dev lookups. For each
1056  * core. DRM core takes care of major-number management and char-dev
1057  * registration. A stub ->open() callback forwards any open() requests to the
1073 	new_fops = fops_get(minor->dev->driver->fops);  in drm_stub_open()
1075 		err = -ENODEV;  in drm_stub_open()
1080 	if (filp->f_op->open)  in drm_stub_open()
1081 		err = filp->f_op->open(inode, filp);  in drm_stub_open()