cdev.h revision 271127 
1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice unmodified, this list of conditions, and the following
13 *    disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#ifndef	_LINUX_CDEV_H_
31#define	_LINUX_CDEV_H_
32
33#include <linux/kobject.h>
34#include <linux/kdev_t.h>
35#include <linux/list.h>
36
37struct file_operations;
38struct inode;
39struct module;
40
41extern struct cdevsw linuxcdevsw;
42
43struct linux_cdev {
44	struct kobject	kobj;
45	struct module	*owner;
46	struct cdev	*cdev;
47	dev_t		dev;
48	const struct file_operations *ops;
49};
50
51static inline void
52cdev_release(struct kobject *kobj)
53{
54	struct linux_cdev *cdev;
55
56	cdev = container_of(kobj, struct linux_cdev, kobj);
57	if (cdev->cdev)
58		destroy_dev(cdev->cdev);
59	kfree(cdev);
60}
61
62static inline void
63cdev_static_release(struct kobject *kobj)
64{
65	struct linux_cdev *cdev;
66
67	cdev = container_of(kobj, struct linux_cdev, kobj);
68	if (cdev->cdev)
69		destroy_dev(cdev->cdev);
70}
71
72static struct kobj_type cdev_ktype = {
73	.release = cdev_release,
74};
75
76static struct kobj_type cdev_static_ktype = {
77	.release = cdev_static_release,
78};
79
80static inline void
81cdev_init(struct linux_cdev *cdev, const struct file_operations *ops)
82{
83
84	kobject_init(&cdev->kobj, &cdev_static_ktype);
85	cdev->ops = ops;
86}
87
88static inline struct linux_cdev *
89cdev_alloc(void)
90{
91	struct linux_cdev *cdev;
92
93	cdev = kzalloc(sizeof(struct linux_cdev), M_WAITOK);
94	if (cdev)
95		kobject_init(&cdev->kobj, &cdev_ktype);
96	return (cdev);
97}
98
99static inline void
100cdev_put(struct linux_cdev *p)
101{
102	kobject_put(&p->kobj);
103}
104
105static inline int
106cdev_add(struct linux_cdev *cdev, dev_t dev, unsigned count)
107{
108	if (count != 1)
109		panic("cdev_add: Unsupported count: %d", count);
110	cdev->cdev = make_dev(&linuxcdevsw, MINOR(dev), 0, 0, 0700,
111	    "%s", kobject_name(&cdev->kobj));
112	cdev->dev = dev;
113	cdev->cdev->si_drv1 = cdev;
114
115	return (0);
116}
117
118static inline void
119cdev_del(struct linux_cdev *cdev)
120{
121	if (cdev->cdev) {
122		destroy_dev(cdev->cdev);
123		cdev->cdev = NULL;
124	}
125	kobject_put(&cdev->kobj);
126}
127
128#define	cdev	linux_cdev
129
130#endif	/* _LINUX_CDEV_H_ */
131