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/genhd.h>
17#include <linux/list.h>
18#include <linux/moduleparam.h>
19#include <linux/device.h>
20
21#include "rnbd-srv.h"
22
23static struct device *rnbd_dev;
24static struct class *rnbd_dev_class;
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			       const char *dev_name)
44{
45	struct kobject *bdev_kobj;
46	int ret;
47
48	ret = kobject_init_and_add(&dev->dev_kobj, &dev_ktype,
49				   rnbd_devs_kobj, dev_name);
50	if (ret)
51		return ret;
52
53	dev->dev_sessions_kobj = kobject_create_and_add("sessions",
54							&dev->dev_kobj);
55	if (!dev->dev_sessions_kobj)
56		goto put_dev_kobj;
57
58	bdev_kobj = &disk_to_dev(bdev->bd_disk)->kobj;
59	ret = sysfs_create_link(&dev->dev_kobj, bdev_kobj, "block_dev");
60	if (ret)
61		goto put_sess_kobj;
62
63	return 0;
64
65put_sess_kobj:
66	kobject_put(dev->dev_sessions_kobj);
67put_dev_kobj:
68	kobject_put(&dev->dev_kobj);
69	return ret;
70}
71
72void rnbd_srv_destroy_dev_sysfs(struct rnbd_srv_dev *dev)
73{
74	sysfs_remove_link(&dev->dev_kobj, "block_dev");
75	kobject_del(dev->dev_sessions_kobj);
76	kobject_put(dev->dev_sessions_kobj);
77	kobject_del(&dev->dev_kobj);
78	kobject_put(&dev->dev_kobj);
79}
80
81static ssize_t read_only_show(struct kobject *kobj, struct kobj_attribute *attr,
82			      char *page)
83{
84	struct rnbd_srv_sess_dev *sess_dev;
85
86	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
87
88	return scnprintf(page, PAGE_SIZE, "%d\n",
89			 !(sess_dev->open_flags & FMODE_WRITE));
90}
91
92static struct kobj_attribute rnbd_srv_dev_session_ro_attr =
93	__ATTR_RO(read_only);
94
95static ssize_t access_mode_show(struct kobject *kobj,
96				struct kobj_attribute *attr,
97				char *page)
98{
99	struct rnbd_srv_sess_dev *sess_dev;
100
101	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
102
103	return scnprintf(page, PAGE_SIZE, "%s\n",
104			 rnbd_access_mode_str(sess_dev->access_mode));
105}
106
107static struct kobj_attribute rnbd_srv_dev_session_access_mode_attr =
108	__ATTR_RO(access_mode);
109
110static ssize_t mapping_path_show(struct kobject *kobj,
111				 struct kobj_attribute *attr, char *page)
112{
113	struct rnbd_srv_sess_dev *sess_dev;
114
115	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
116
117	return scnprintf(page, PAGE_SIZE, "%s\n", sess_dev->pathname);
118}
119
120static struct kobj_attribute rnbd_srv_dev_session_mapping_path_attr =
121	__ATTR_RO(mapping_path);
122
123static struct attribute *rnbd_srv_default_dev_sessions_attrs[] = {
124	&rnbd_srv_dev_session_access_mode_attr.attr,
125	&rnbd_srv_dev_session_ro_attr.attr,
126	&rnbd_srv_dev_session_mapping_path_attr.attr,
127	NULL,
128};
129
130static struct attribute_group rnbd_srv_default_dev_session_attr_group = {
131	.attrs = rnbd_srv_default_dev_sessions_attrs,
132};
133
134void rnbd_srv_destroy_dev_session_sysfs(struct rnbd_srv_sess_dev *sess_dev)
135{
136	sysfs_remove_group(&sess_dev->kobj,
137			   &rnbd_srv_default_dev_session_attr_group);
138
139	kobject_del(&sess_dev->kobj);
140	kobject_put(&sess_dev->kobj);
141}
142
143static void rnbd_srv_sess_dev_release(struct kobject *kobj)
144{
145	struct rnbd_srv_sess_dev *sess_dev;
146
147	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
148	rnbd_destroy_sess_dev(sess_dev);
149}
150
151static struct kobj_type rnbd_srv_sess_dev_ktype = {
152	.sysfs_ops	= &kobj_sysfs_ops,
153	.release	= rnbd_srv_sess_dev_release,
154};
155
156int rnbd_srv_create_dev_session_sysfs(struct rnbd_srv_sess_dev *sess_dev)
157{
158	int ret;
159
160	ret = kobject_init_and_add(&sess_dev->kobj, &rnbd_srv_sess_dev_ktype,
161				   sess_dev->dev->dev_sessions_kobj, "%s",
162				   sess_dev->sess->sessname);
163	if (ret)
164		return ret;
165
166	ret = sysfs_create_group(&sess_dev->kobj,
167				 &rnbd_srv_default_dev_session_attr_group);
168	if (ret)
169		goto err;
170
171	return 0;
172
173err:
174	kobject_put(&sess_dev->kobj);
175
176	return ret;
177}
178
179int rnbd_srv_create_sysfs_files(void)
180{
181	int err;
182
183	rnbd_dev_class = class_create(THIS_MODULE, "rnbd-server");
184	if (IS_ERR(rnbd_dev_class))
185		return PTR_ERR(rnbd_dev_class);
186
187	rnbd_dev = device_create(rnbd_dev_class, NULL,
188				  MKDEV(0, 0), NULL, "ctl");
189	if (IS_ERR(rnbd_dev)) {
190		err = PTR_ERR(rnbd_dev);
191		goto cls_destroy;
192	}
193	rnbd_devs_kobj = kobject_create_and_add("devices", &rnbd_dev->kobj);
194	if (!rnbd_devs_kobj) {
195		err = -ENOMEM;
196		goto dev_destroy;
197	}
198
199	return 0;
200
201dev_destroy:
202	device_destroy(rnbd_dev_class, MKDEV(0, 0));
203cls_destroy:
204	class_destroy(rnbd_dev_class);
205
206	return err;
207}
208
209void rnbd_srv_destroy_sysfs_files(void)
210{
211	kobject_del(rnbd_devs_kobj);
212	kobject_put(rnbd_devs_kobj);
213	device_destroy(rnbd_dev_class, MKDEV(0, 0));
214	class_destroy(rnbd_dev_class);
215}
216