xref: /linux-6.15/include/linux/connector.h (revision 35a8a3fd)
1 /*
2  * 	connector.h
3  *
4  * 2004-2005 Copyright (c) Evgeniy Polyakov <[email protected]>
5  * All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #ifndef __CONNECTOR_H
23 #define __CONNECTOR_H
24 
25 #include <linux/types.h>
26 
27 #define CN_IDX_CONNECTOR		0xffffffff
28 #define CN_VAL_CONNECTOR		0xffffffff
29 
30 /*
31  * Process Events connector unique ids -- used for message routing
32  */
33 #define CN_IDX_PROC			0x1
34 #define CN_VAL_PROC			0x1
35 #define CN_IDX_CIFS			0x2
36 #define CN_VAL_CIFS                     0x1
37 #define CN_W1_IDX			0x3	/* w1 communication */
38 #define CN_W1_VAL			0x1
39 #define CN_IDX_V86D			0x4
40 #define CN_VAL_V86D_UVESAFB		0x1
41 #define CN_IDX_BB			0x5	/* BlackBoard, from the TSP GPL sampling framework */
42 #define CN_DST_IDX			0x6
43 #define CN_DST_VAL			0x1
44 #define CN_IDX_DM			0x7	/* Device Mapper */
45 #define CN_VAL_DM_USERSPACE_LOG		0x1
46 #define CN_IDX_DRBD			0x8
47 #define CN_VAL_DRBD			0x1
48 
49 #define CN_NETLINK_USERS		8
50 
51 /*
52  * Maximum connector's message size.
53  */
54 #define CONNECTOR_MAX_MSG_SIZE		16384
55 
56 /*
57  * idx and val are unique identifiers which
58  * are used for message routing and
59  * must be registered in connector.h for in-kernel usage.
60  */
61 
62 struct cb_id {
63 	__u32 idx;
64 	__u32 val;
65 };
66 
67 struct cn_msg {
68 	struct cb_id id;
69 
70 	__u32 seq;
71 	__u32 ack;
72 
73 	__u16 len;		/* Length of the following data */
74 	__u16 flags;
75 	__u8 data[0];
76 };
77 
78 /*
79  * Notify structure - requests notification about
80  * registering/unregistering idx/val in range [first, first+range].
81  */
82 struct cn_notify_req {
83 	__u32 first;
84 	__u32 range;
85 };
86 
87 /*
88  * Main notification control message
89  * *_notify_num 	- number of appropriate cn_notify_req structures after
90  *				this struct.
91  * group 		- notification receiver's idx.
92  * len 			- total length of the attached data.
93  */
94 struct cn_ctl_msg {
95 	__u32 idx_notify_num;
96 	__u32 val_notify_num;
97 	__u32 group;
98 	__u32 len;
99 	__u8 data[0];
100 };
101 
102 #ifdef __KERNEL__
103 
104 #include <asm/atomic.h>
105 
106 #include <linux/list.h>
107 #include <linux/workqueue.h>
108 
109 #include <net/sock.h>
110 
111 #define CN_CBQ_NAMELEN		32
112 
113 struct cn_queue_dev {
114 	atomic_t refcnt;
115 	unsigned char name[CN_CBQ_NAMELEN];
116 
117 	struct workqueue_struct *cn_queue;
118 	/* Sent to kevent to create cn_queue only when needed */
119 	struct work_struct wq_creation;
120 	/* Tell if the wq_creation job is pending/completed */
121 	atomic_t wq_requested;
122 	/* Wait for cn_queue to be created */
123 	wait_queue_head_t wq_created;
124 
125 	struct list_head queue_list;
126 	spinlock_t queue_lock;
127 
128 	struct sock *nls;
129 };
130 
131 struct cn_callback_id {
132 	unsigned char name[CN_CBQ_NAMELEN];
133 	struct cb_id id;
134 };
135 
136 struct cn_callback_data {
137 	struct sk_buff *skb;
138 	void (*callback) (struct cn_msg *, struct netlink_skb_parms *);
139 
140 	void *free;
141 };
142 
143 struct cn_callback_entry {
144 	struct list_head callback_entry;
145 	struct work_struct work;
146 	struct cn_queue_dev *pdev;
147 
148 	struct cn_callback_id id;
149 	struct cn_callback_data data;
150 
151 	u32 seq, group;
152 };
153 
154 struct cn_ctl_entry {
155 	struct list_head notify_entry;
156 	struct cn_ctl_msg *msg;
157 };
158 
159 struct cn_dev {
160 	struct cb_id id;
161 
162 	u32 seq, groups;
163 	struct sock *nls;
164 	void (*input) (struct sk_buff *skb);
165 
166 	struct cn_queue_dev *cbdev;
167 };
168 
169 int cn_add_callback(struct cb_id *, char *, void (*callback) (struct cn_msg *, struct netlink_skb_parms *));
170 void cn_del_callback(struct cb_id *);
171 int cn_netlink_send(struct cn_msg *, u32, gfp_t);
172 
173 int cn_queue_add_callback(struct cn_queue_dev *dev, char *name, struct cb_id *id, void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
174 void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id);
175 
176 int queue_cn_work(struct cn_callback_entry *cbq, struct work_struct *work);
177 
178 struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *);
179 void cn_queue_free_dev(struct cn_queue_dev *dev);
180 
181 int cn_cb_equal(struct cb_id *, struct cb_id *);
182 
183 void cn_queue_wrapper(struct work_struct *work);
184 
185 #endif				/* __KERNEL__ */
186 #endif				/* __CONNECTOR_H */
187