1 /*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2021 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 #ifndef _LINUXKPI_LINUX_CDEV_H_
30 #define _LINUXKPI_LINUX_CDEV_H_
31
32 #include <linux/kobject.h>
33 #include <linux/sysfs.h>
34 #include <linux/kdev_t.h>
35 #include <linux/list.h>
36
37 #include <asm/atomic-long.h>
38
39 struct device;
40 struct file_operations;
41 struct inode;
42 struct module;
43
44 extern struct cdevsw linuxcdevsw;
45 extern const struct kobj_type linux_cdev_ktype;
46 extern const struct kobj_type linux_cdev_static_ktype;
47
48 struct linux_cdev {
49 struct kobject kobj;
50 struct module *owner;
51 struct cdev *cdev;
52 dev_t dev;
53 const struct file_operations *ops;
54 u_int refs;
55 u_int siref;
56 };
57
58 struct linux_cdev *cdev_alloc(void);
59
60 static inline void
cdev_init(struct linux_cdev * cdev,const struct file_operations * ops)61 cdev_init(struct linux_cdev *cdev, const struct file_operations *ops)
62 {
63
64 kobject_init(&cdev->kobj, &linux_cdev_static_ktype);
65 cdev->ops = ops;
66 cdev->refs = 1;
67 }
68
69 static inline void
cdev_put(struct linux_cdev * p)70 cdev_put(struct linux_cdev *p)
71 {
72 kobject_put(&p->kobj);
73 }
74
75 static inline int
cdev_add(struct linux_cdev * cdev,dev_t dev,unsigned count)76 cdev_add(struct linux_cdev *cdev, dev_t dev, unsigned count)
77 {
78 struct make_dev_args args;
79 int error;
80
81 if (count != 1)
82 return (-EINVAL);
83
84 cdev->dev = dev;
85
86 /* Setup arguments for make_dev_s() */
87 make_dev_args_init(&args);
88 args.mda_devsw = &linuxcdevsw;
89 args.mda_uid = 0;
90 args.mda_gid = 0;
91 args.mda_mode = 0700;
92 args.mda_si_drv1 = cdev;
93
94 error = make_dev_s(&args, &cdev->cdev, "%s",
95 kobject_name(&cdev->kobj));
96 if (error)
97 return (-error);
98
99 kobject_get(cdev->kobj.parent);
100 return (0);
101 }
102
103 static inline int
cdev_add_ext(struct linux_cdev * cdev,dev_t dev,uid_t uid,gid_t gid,int mode)104 cdev_add_ext(struct linux_cdev *cdev, dev_t dev, uid_t uid, gid_t gid, int mode)
105 {
106 struct make_dev_args args;
107 int error;
108
109 cdev->dev = dev;
110
111 /* Setup arguments for make_dev_s() */
112 make_dev_args_init(&args);
113 args.mda_devsw = &linuxcdevsw;
114 args.mda_uid = uid;
115 args.mda_gid = gid;
116 args.mda_mode = mode;
117 args.mda_si_drv1 = cdev;
118
119 error = make_dev_s(&args, &cdev->cdev, "%s/%d",
120 kobject_name(&cdev->kobj), MINOR(dev));
121 if (error)
122 return (-error);
123
124 kobject_get(cdev->kobj.parent);
125 return (0);
126 }
127
128 static inline void
cdev_del(struct linux_cdev * cdev)129 cdev_del(struct linux_cdev *cdev)
130 {
131 kobject_put(&cdev->kobj);
132 }
133
134 struct linux_cdev *linux_find_cdev(const char *name, unsigned major, unsigned minor);
135
136 int linux_cdev_device_add(struct linux_cdev *, struct device *);
137 void linux_cdev_device_del(struct linux_cdev *, struct device *);
138
139 #define cdev_device_add(...) \
140 linux_cdev_device_add(__VA_ARGS__)
141 #define cdev_device_del(...) \
142 linux_cdev_device_del(__VA_ARGS__)
143
144 #define cdev linux_cdev
145
146 #endif /* _LINUXKPI_LINUX_CDEV_H_ */
147