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(objp: 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(kobj: &dev->dev_kobj, ktype: &dev_ktype,
48 parent: rnbd_devs_kobj, fmt: "%pg", bdev);
49 if (ret) {
50 kobject_put(kobj: &dev->dev_kobj);
51 return ret;
52 }
53
54 dev->dev_sessions_kobj = kobject_create_and_add(name: "sessions",
55 parent: &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(kobj: &dev->dev_kobj, target: bdev_kobj, name: "block_dev");
63 if (ret)
64 goto put_sess_kobj;
65
66 return 0;
67
68put_sess_kobj:
69 kobject_put(kobj: dev->dev_sessions_kobj);
70free_dev_kobj:
71 kobject_del(kobj: &dev->dev_kobj);
72 kobject_put(kobj: &dev->dev_kobj);
73 return ret;
74}
75
76void rnbd_srv_destroy_dev_sysfs(struct rnbd_srv_dev *dev)
77{
78 sysfs_remove_link(kobj: &dev->dev_kobj, name: "block_dev");
79 kobject_del(kobj: dev->dev_sessions_kobj);
80 kobject_put(kobj: dev->dev_sessions_kobj);
81 kobject_del(kobj: &dev->dev_kobj);
82 kobject_put(kobj: &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(buf: page, fmt: "%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(buf: page, fmt: "%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(buf: page, fmt: "%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(buf: page, fmt: "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(s1: buf, s2: "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(kobj: &sess_dev->kobj,
173 grp: &rnbd_srv_default_dev_session_attr_group);
174
175 kobject_del(kobj: &sess_dev->kobj);
176 kobject_put(kobj: &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, keep_id: 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(kobj: &sess_dev->kobj, ktype: &rnbd_srv_sess_dev_ktype,
197 parent: sess_dev->dev->dev_sessions_kobj, fmt: "%s",
198 sess_dev->sess->sessname);
199 if (ret) {
200 kobject_put(kobj: &sess_dev->kobj);
201 return ret;
202 }
203
204 ret = sysfs_create_group(kobj: &sess_dev->kobj,
205 grp: &rnbd_srv_default_dev_session_attr_group);
206 if (ret) {
207 kobject_del(kobj: &sess_dev->kobj);
208 kobject_put(kobj: &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(class: &rnbd_dev_class);
219 if (err)
220 return err;
221
222 rnbd_dev = device_create(cls: &rnbd_dev_class, NULL,
223 MKDEV(0, 0), NULL, fmt: "ctl");
224 if (IS_ERR(ptr: rnbd_dev)) {
225 err = PTR_ERR(ptr: rnbd_dev);
226 goto cls_destroy;
227 }
228 rnbd_devs_kobj = kobject_create_and_add(name: "devices", parent: &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(cls: &rnbd_dev_class, MKDEV(0, 0));
238cls_destroy:
239 class_unregister(class: &rnbd_dev_class);
240
241 return err;
242}
243
244void rnbd_srv_destroy_sysfs_files(void)
245{
246 kobject_del(kobj: rnbd_devs_kobj);
247 kobject_put(kobj: rnbd_devs_kobj);
248 device_destroy(cls: &rnbd_dev_class, MKDEV(0, 0));
249 class_unregister(class: &rnbd_dev_class);
250}
251

source code of linux/drivers/block/rnbd/rnbd-srv-sysfs.c