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 <uapi/linux/limits.h>
13 #include <linux/kobject.h>
14 #include <linux/sysfs.h>
15 #include <linux/stat.h>
16 #include <linux/list.h>
17 #include <linux/moduleparam.h>
18 #include <linux/device.h>
19
20 #include "rnbd-srv.h"
21
22 static struct device *rnbd_dev;
23 static struct class *rnbd_dev_class;
24 static struct kobject *rnbd_devs_kobj;
25
rnbd_srv_dev_release(struct kobject * kobj)26 static void rnbd_srv_dev_release(struct kobject *kobj)
27 {
28 struct rnbd_srv_dev *dev;
29
30 dev = container_of(kobj, struct rnbd_srv_dev, dev_kobj);
31
32 kfree(dev);
33 }
34
35 static struct kobj_type dev_ktype = {
36 .sysfs_ops = &kobj_sysfs_ops,
37 .release = rnbd_srv_dev_release
38 };
39
rnbd_srv_create_dev_sysfs(struct rnbd_srv_dev * dev,struct block_device * bdev)40 int rnbd_srv_create_dev_sysfs(struct rnbd_srv_dev *dev,
41 struct block_device *bdev)
42 {
43 struct kobject *bdev_kobj;
44 int ret;
45
46 ret = kobject_init_and_add(&dev->dev_kobj, &dev_ktype,
47 rnbd_devs_kobj, "%pg", bdev);
48 if (ret) {
49 kobject_put(&dev->dev_kobj);
50 return ret;
51 }
52
53 dev->dev_sessions_kobj = kobject_create_and_add("sessions",
54 &dev->dev_kobj);
55 if (!dev->dev_sessions_kobj) {
56 ret = -ENOMEM;
57 goto free_dev_kobj;
58 }
59
60 bdev_kobj = &disk_to_dev(bdev->bd_disk)->kobj;
61 ret = sysfs_create_link(&dev->dev_kobj, bdev_kobj, "block_dev");
62 if (ret)
63 goto put_sess_kobj;
64
65 return 0;
66
67 put_sess_kobj:
68 kobject_put(dev->dev_sessions_kobj);
69 free_dev_kobj:
70 kobject_del(&dev->dev_kobj);
71 kobject_put(&dev->dev_kobj);
72 return ret;
73 }
74
rnbd_srv_destroy_dev_sysfs(struct rnbd_srv_dev * dev)75 void rnbd_srv_destroy_dev_sysfs(struct rnbd_srv_dev *dev)
76 {
77 sysfs_remove_link(&dev->dev_kobj, "block_dev");
78 kobject_del(dev->dev_sessions_kobj);
79 kobject_put(dev->dev_sessions_kobj);
80 kobject_del(&dev->dev_kobj);
81 kobject_put(&dev->dev_kobj);
82 }
83
read_only_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)84 static ssize_t read_only_show(struct kobject *kobj, struct kobj_attribute *attr,
85 char *page)
86 {
87 struct rnbd_srv_sess_dev *sess_dev;
88
89 sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
90
91 return sysfs_emit(page, "%d\n",
92 !(sess_dev->open_flags & FMODE_WRITE));
93 }
94
95 static struct kobj_attribute rnbd_srv_dev_session_ro_attr =
96 __ATTR_RO(read_only);
97
access_mode_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)98 static 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_mode_str(sess_dev->access_mode));
108 }
109
110 static struct kobj_attribute rnbd_srv_dev_session_access_mode_attr =
111 __ATTR_RO(access_mode);
112
mapping_path_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)113 static 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
123 static struct kobj_attribute rnbd_srv_dev_session_mapping_path_attr =
124 __ATTR_RO(mapping_path);
125
rnbd_srv_dev_session_force_close_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)126 static 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
rnbd_srv_dev_session_force_close_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t count)133 static 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
153 static 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
158 static 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
166 static struct attribute_group rnbd_srv_default_dev_session_attr_group = {
167 .attrs = rnbd_srv_default_dev_sessions_attrs,
168 };
169
rnbd_srv_destroy_dev_session_sysfs(struct rnbd_srv_sess_dev * sess_dev)170 void 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
rnbd_srv_sess_dev_release(struct kobject * kobj)179 static 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
187 static struct kobj_type rnbd_srv_sess_dev_ktype = {
188 .sysfs_ops = &kobj_sysfs_ops,
189 .release = rnbd_srv_sess_dev_release,
190 };
191
rnbd_srv_create_dev_session_sysfs(struct rnbd_srv_sess_dev * sess_dev)192 int 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
rnbd_srv_create_sysfs_files(void)214 int rnbd_srv_create_sysfs_files(void)
215 {
216 int err;
217
218 rnbd_dev_class = class_create(THIS_MODULE, "rnbd-server");
219 if (IS_ERR(rnbd_dev_class))
220 return PTR_ERR(rnbd_dev_class);
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
236 dev_destroy:
237 device_destroy(rnbd_dev_class, MKDEV(0, 0));
238 cls_destroy:
239 class_destroy(rnbd_dev_class);
240
241 return err;
242 }
243
rnbd_srv_destroy_sysfs_files(void)244 void 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_destroy(rnbd_dev_class);
250 }
251