1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RDMA Network Block Driver
4 *
5 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
6 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
7 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
8 */
9#undef pr_fmt
10#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
11
12#include <linux/kobject.h>
13#include <linux/sysfs.h>
14#include <linux/stat.h>
15#include <linux/list.h>
16#include <linux/moduleparam.h>
17#include <linux/device.h>
18
19#include "rnbd-srv.h"
20
21static struct device *rnbd_dev;
22static const struct class rnbd_dev_class = {
23	.name = "rnbd-server",
24};
25static struct kobject *rnbd_devs_kobj;
26
27static void rnbd_srv_dev_release(struct kobject *kobj)
28{
29	struct rnbd_srv_dev *dev;
30
31	dev = container_of(kobj, struct rnbd_srv_dev, dev_kobj);
32
33	kfree(dev);
34}
35
36static struct kobj_type dev_ktype = {
37	.sysfs_ops = &kobj_sysfs_ops,
38	.release = rnbd_srv_dev_release
39};
40
41int rnbd_srv_create_dev_sysfs(struct rnbd_srv_dev *dev,
42			       struct block_device *bdev)
43{
44	struct kobject *bdev_kobj;
45	int ret;
46
47	ret = kobject_init_and_add(&dev->dev_kobj, &dev_ktype,
48				   rnbd_devs_kobj, "%pg", bdev);
49	if (ret) {
50		kobject_put(&dev->dev_kobj);
51		return ret;
52	}
53
54	dev->dev_sessions_kobj = kobject_create_and_add("sessions",
55							&dev->dev_kobj);
56	if (!dev->dev_sessions_kobj) {
57		ret = -ENOMEM;
58		goto free_dev_kobj;
59	}
60
61	bdev_kobj = &disk_to_dev(bdev->bd_disk)->kobj;
62	ret = sysfs_create_link(&dev->dev_kobj, bdev_kobj, "block_dev");
63	if (ret)
64		goto put_sess_kobj;
65
66	return 0;
67
68put_sess_kobj:
69	kobject_put(dev->dev_sessions_kobj);
70free_dev_kobj:
71	kobject_del(&dev->dev_kobj);
72	kobject_put(&dev->dev_kobj);
73	return ret;
74}
75
76void rnbd_srv_destroy_dev_sysfs(struct rnbd_srv_dev *dev)
77{
78	sysfs_remove_link(&dev->dev_kobj, "block_dev");
79	kobject_del(dev->dev_sessions_kobj);
80	kobject_put(dev->dev_sessions_kobj);
81	kobject_del(&dev->dev_kobj);
82	kobject_put(&dev->dev_kobj);
83}
84
85static ssize_t read_only_show(struct kobject *kobj, struct kobj_attribute *attr,
86			      char *page)
87{
88	struct rnbd_srv_sess_dev *sess_dev;
89
90	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
91
92	return sysfs_emit(page, "%d\n", sess_dev->readonly);
93}
94
95static struct kobj_attribute rnbd_srv_dev_session_ro_attr =
96	__ATTR_RO(read_only);
97
98static ssize_t access_mode_show(struct kobject *kobj,
99				struct kobj_attribute *attr,
100				char *page)
101{
102	struct rnbd_srv_sess_dev *sess_dev;
103
104	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
105
106	return sysfs_emit(page, "%s\n",
107			  rnbd_access_modes[sess_dev->access_mode].str);
108}
109
110static struct kobj_attribute rnbd_srv_dev_session_access_mode_attr =
111	__ATTR_RO(access_mode);
112
113static ssize_t mapping_path_show(struct kobject *kobj,
114				 struct kobj_attribute *attr, char *page)
115{
116	struct rnbd_srv_sess_dev *sess_dev;
117
118	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
119
120	return sysfs_emit(page, "%s\n", sess_dev->pathname);
121}
122
123static struct kobj_attribute rnbd_srv_dev_session_mapping_path_attr =
124	__ATTR_RO(mapping_path);
125
126static ssize_t rnbd_srv_dev_session_force_close_show(struct kobject *kobj,
127					struct kobj_attribute *attr, char *page)
128{
129	return sysfs_emit(page, "Usage: echo 1 > %s\n",
130			  attr->attr.name);
131}
132
133static ssize_t rnbd_srv_dev_session_force_close_store(struct kobject *kobj,
134					struct kobj_attribute *attr,
135					const char *buf, size_t count)
136{
137	struct rnbd_srv_sess_dev *sess_dev;
138
139	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
140
141	if (!sysfs_streq(buf, "1")) {
142		rnbd_srv_err(sess_dev, "%s: invalid value: '%s'\n",
143			      attr->attr.name, buf);
144		return -EINVAL;
145	}
146
147	rnbd_srv_info(sess_dev, "force close requested\n");
148	rnbd_srv_sess_dev_force_close(sess_dev, attr);
149
150	return count;
151}
152
153static struct kobj_attribute rnbd_srv_dev_session_force_close_attr =
154	__ATTR(force_close, 0644,
155	       rnbd_srv_dev_session_force_close_show,
156	       rnbd_srv_dev_session_force_close_store);
157
158static struct attribute *rnbd_srv_default_dev_sessions_attrs[] = {
159	&rnbd_srv_dev_session_access_mode_attr.attr,
160	&rnbd_srv_dev_session_ro_attr.attr,
161	&rnbd_srv_dev_session_mapping_path_attr.attr,
162	&rnbd_srv_dev_session_force_close_attr.attr,
163	NULL,
164};
165
166static struct attribute_group rnbd_srv_default_dev_session_attr_group = {
167	.attrs = rnbd_srv_default_dev_sessions_attrs,
168};
169
170void rnbd_srv_destroy_dev_session_sysfs(struct rnbd_srv_sess_dev *sess_dev)
171{
172	sysfs_remove_group(&sess_dev->kobj,
173			   &rnbd_srv_default_dev_session_attr_group);
174
175	kobject_del(&sess_dev->kobj);
176	kobject_put(&sess_dev->kobj);
177}
178
179static void rnbd_srv_sess_dev_release(struct kobject *kobj)
180{
181	struct rnbd_srv_sess_dev *sess_dev;
182
183	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
184	rnbd_destroy_sess_dev(sess_dev, sess_dev->keep_id);
185}
186
187static struct kobj_type rnbd_srv_sess_dev_ktype = {
188	.sysfs_ops	= &kobj_sysfs_ops,
189	.release	= rnbd_srv_sess_dev_release,
190};
191
192int rnbd_srv_create_dev_session_sysfs(struct rnbd_srv_sess_dev *sess_dev)
193{
194	int ret;
195
196	ret = kobject_init_and_add(&sess_dev->kobj, &rnbd_srv_sess_dev_ktype,
197				   sess_dev->dev->dev_sessions_kobj, "%s",
198				   sess_dev->sess->sessname);
199	if (ret) {
200		kobject_put(&sess_dev->kobj);
201		return ret;
202	}
203
204	ret = sysfs_create_group(&sess_dev->kobj,
205				 &rnbd_srv_default_dev_session_attr_group);
206	if (ret) {
207		kobject_del(&sess_dev->kobj);
208		kobject_put(&sess_dev->kobj);
209	}
210
211	return ret;
212}
213
214int rnbd_srv_create_sysfs_files(void)
215{
216	int err;
217
218	err = class_register(&rnbd_dev_class);
219	if (err)
220		return err;
221
222	rnbd_dev = device_create(&rnbd_dev_class, NULL,
223				 MKDEV(0, 0), NULL, "ctl");
224	if (IS_ERR(rnbd_dev)) {
225		err = PTR_ERR(rnbd_dev);
226		goto cls_destroy;
227	}
228	rnbd_devs_kobj = kobject_create_and_add("devices", &rnbd_dev->kobj);
229	if (!rnbd_devs_kobj) {
230		err = -ENOMEM;
231		goto dev_destroy;
232	}
233
234	return 0;
235
236dev_destroy:
237	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
238cls_destroy:
239	class_unregister(&rnbd_dev_class);
240
241	return err;
242}
243
244void rnbd_srv_destroy_sysfs_files(void)
245{
246	kobject_del(rnbd_devs_kobj);
247	kobject_put(rnbd_devs_kobj);
248	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
249	class_unregister(&rnbd_dev_class);
250}
251