// SPDX-License-Identifier: GPL-2.0-only/* * File attributes for Mediated devices * * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. *     Author: Neo Jia <cjia@nvidia.com> *             Kirti Wankhede <kwankhede@nvidia.com> */ #include <linux/sysfs.h>#include <linux/ctype.h>#include <linux/device.h>#include <linux/slab.h>#include <linux/uuid.h>#include <linux/mdev.h> #include "mdev_private.h" /* Static functions */ static ssize_t mdev_type_attr_show(struct kobject *kobj,				     struct attribute *__attr, char *buf){	struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);	struct mdev_type *type = to_mdev_type(kobj);	ssize_t ret = -EIO; 	if (attr->show)		ret = attr->show(type, attr, buf);	return ret;} static ssize_t mdev_type_attr_store(struct kobject *kobj,				      struct attribute *__attr,				      const char *buf, size_t count){	struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);	struct mdev_type *type = to_mdev_type(kobj);	ssize_t ret = -EIO; 	if (attr->store)		ret = attr->store(type, attr, buf, count);	return ret;} static const struct sysfs_ops mdev_type_sysfs_ops = {	.show = mdev_type_attr_show,	.store = mdev_type_attr_store,}; static ssize_t create_store(struct mdev_type *mtype,			    struct mdev_type_attribute *attr, const char *buf,			    size_t count){	char *str;	guid_t uuid;	int ret; 	if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))		return -EINVAL; 	str = kstrndup(buf, count, GFP_KERNEL);	if (!str)		return -ENOMEM; 	ret = guid_parse(str, &uuid);	kfree(str);	if (ret)		return ret; 	ret = mdev_device_create(mtype, &uuid);	if (ret)		return ret; 	return count;} static MDEV_TYPE_ATTR_WO(create); static void mdev_type_release(struct kobject *kobj){	struct mdev_type *type = to_mdev_type(kobj); 	pr_debug("Releasing group %s\n", kobj->name);	/* Pairs with the get in add_mdev_supported_type() */	mdev_put_parent(type->parent);	kfree(type);} static struct kobj_type mdev_type_ktype = {	.sysfs_ops = &mdev_type_sysfs_ops,	.release = mdev_type_release,}; static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,						 unsigned int type_group_id){	struct mdev_type *type;	struct attribute_group *group =		parent->mdev_driver->supported_type_groups[type_group_id];	int ret; 	if (!group->name) {		pr_err("%s: Type name empty!\n", __func__);		return ERR_PTR(-EINVAL);	} 	type = kzalloc(sizeof(*type), GFP_KERNEL);	if (!type)		return ERR_PTR(-ENOMEM); 	type->kobj.kset = parent->mdev_types_kset;	type->parent = parent;	/* Pairs with the put in mdev_type_release() */	mdev_get_parent(parent);	type->type_group_id = type_group_id; 	ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,				   "%s-%s", dev_driver_string(parent->dev),				   group->name);	if (ret) {		kobject_put(&type->kobj);		return ERR_PTR(ret);	} 	ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);	if (ret)		goto attr_create_failed; 	type->devices_kobj = kobject_create_and_add("devices", &type->kobj);	if (!type->devices_kobj) {		ret = -ENOMEM;		goto attr_devices_failed;	} 	ret = sysfs_create_files(&type->kobj,				 (const struct attribute **)group->attrs);	if (ret) {		ret = -ENOMEM;		goto attrs_failed;	}	return type; attrs_failed:	kobject_put(type->devices_kobj);attr_devices_failed:	sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);attr_create_failed:	kobject_del(&type->kobj);	kobject_put(&type->kobj);	return ERR_PTR(ret);} static void remove_mdev_supported_type(struct mdev_type *type){	struct attribute_group *group =		type->parent->mdev_driver->supported_type_groups[type->type_group_id]; 	sysfs_remove_files(&type->kobj,			   (const struct attribute **)group->attrs);	kobject_put(type->devices_kobj);	sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);	kobject_del(&type->kobj);	kobject_put(&type->kobj);} static int add_mdev_supported_type_groups(struct mdev_parent *parent){	int i; 	for (i = 0; parent->mdev_driver->supported_type_groups[i]; i++) {		struct mdev_type *type; 		type = add_mdev_supported_type(parent, i);		if (IS_ERR(type)) {			struct mdev_type *ltype, *tmp; 			list_for_each_entry_safe(ltype, tmp, &parent->type_list,						  next) {				list_del(&ltype->next);				remove_mdev_supported_type(ltype);			}			return PTR_ERR(type);		}		list_add(&type->next, &parent->type_list);	}	return 0;} /* mdev sysfs functions */void parent_remove_sysfs_files(struct mdev_parent *parent){	struct mdev_type *type, *tmp; 	list_for_each_entry_safe(type, tmp, &parent->type_list, next) {		list_del(&type->next);		remove_mdev_supported_type(type);	} 	kset_unregister(parent->mdev_types_kset);} int parent_create_sysfs_files(struct mdev_parent *parent){	int ret; 	parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",					       NULL, &parent->dev->kobj); 	if (!parent->mdev_types_kset)		return -ENOMEM; 	INIT_LIST_HEAD(&parent->type_list); 	ret = add_mdev_supported_type_groups(parent);	if (ret)		goto create_err;	return 0; create_err:	kset_unregister(parent->mdev_types_kset);	return ret;} static ssize_t remove_store(struct device *dev, struct device_attribute *attr,			    const char *buf, size_t count){	struct mdev_device *mdev = to_mdev_device(dev);	unsigned long val; 	if (kstrtoul(buf, 0, &val) < 0)		return -EINVAL; 	if (val && device_remove_file_self(dev, attr)) {		int ret; 		ret = mdev_device_remove(mdev);		if (ret)			return ret;	} 	return count;} static DEVICE_ATTR_WO(remove); static struct attribute *mdev_device_attrs[] = {	&dev_attr_remove.attr,	NULL,}; static const struct attribute_group mdev_device_group = {	.attrs = mdev_device_attrs,}; const struct attribute_group *mdev_device_groups[] = {	&mdev_device_group,	NULL}; int mdev_create_sysfs_files(struct mdev_device *mdev){	struct mdev_type *type = mdev->type;	struct kobject *kobj = &mdev->dev.kobj;	int ret; 	ret = sysfs_create_link(type->devices_kobj, kobj, dev_name(&mdev->dev));	if (ret)		return ret; 	ret = sysfs_create_link(kobj, &type->kobj, "mdev_type");	if (ret)		goto type_link_failed;	return ret; type_link_failed:	sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev));	return ret;} void mdev_remove_sysfs_files(struct mdev_device *mdev){	struct kobject *kobj = &mdev->dev.kobj; 	sysfs_remove_link(kobj, "mdev_type");	sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev));}