xref: /linux-6.15/include/linux/connector.h (revision 71ccc212)
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 /*
28  * Process Events connector unique ids -- used for message routing
29  */
30 #define CN_IDX_PROC			0x1
31 #define CN_VAL_PROC			0x1
32 #define CN_IDX_CIFS			0x2
33 #define CN_VAL_CIFS                     0x1
34 #define CN_W1_IDX			0x3	/* w1 communication */
35 #define CN_W1_VAL			0x1
36 #define CN_IDX_V86D			0x4
37 #define CN_VAL_V86D_UVESAFB		0x1
38 #define CN_IDX_BB			0x5	/* BlackBoard, from the TSP GPL sampling framework */
39 #define CN_DST_IDX			0x6
40 #define CN_DST_VAL			0x1
41 #define CN_IDX_DM			0x7	/* Device Mapper */
42 #define CN_VAL_DM_USERSPACE_LOG		0x1
43 #define CN_IDX_DRBD			0x8
44 #define CN_VAL_DRBD			0x1
45 
46 #define CN_NETLINK_USERS		8
47 
48 /*
49  * Maximum connector's message size.
50  */
51 #define CONNECTOR_MAX_MSG_SIZE		16384
52 
53 /*
54  * idx and val are unique identifiers which
55  * are used for message routing and
56  * must be registered in connector.h for in-kernel usage.
57  */
58 
59 struct cb_id {
60 	__u32 idx;
61 	__u32 val;
62 };
63 
64 struct cn_msg {
65 	struct cb_id id;
66 
67 	__u32 seq;
68 	__u32 ack;
69 
70 	__u16 len;		/* Length of the following data */
71 	__u16 flags;
72 	__u8 data[0];
73 };
74 
75 #ifdef __KERNEL__
76 
77 #include <asm/atomic.h>
78 
79 #include <linux/list.h>
80 #include <linux/workqueue.h>
81 
82 #include <net/sock.h>
83 
84 #define CN_CBQ_NAMELEN		32
85 
86 struct cn_queue_dev {
87 	atomic_t refcnt;
88 	unsigned char name[CN_CBQ_NAMELEN];
89 
90 	struct workqueue_struct *cn_queue;
91 	/* Sent to kevent to create cn_queue only when needed */
92 	struct work_struct wq_creation;
93 	/* Tell if the wq_creation job is pending/completed */
94 	atomic_t wq_requested;
95 	/* Wait for cn_queue to be created */
96 	wait_queue_head_t wq_created;
97 
98 	struct list_head queue_list;
99 	spinlock_t queue_lock;
100 
101 	struct sock *nls;
102 };
103 
104 struct cn_callback_id {
105 	unsigned char name[CN_CBQ_NAMELEN];
106 	struct cb_id id;
107 };
108 
109 struct cn_callback_data {
110 	struct sk_buff *skb;
111 	void (*callback) (struct cn_msg *, struct netlink_skb_parms *);
112 
113 	void *free;
114 };
115 
116 struct cn_callback_entry {
117 	struct list_head callback_entry;
118 	struct work_struct work;
119 	struct cn_queue_dev *pdev;
120 
121 	struct cn_callback_id id;
122 	struct cn_callback_data data;
123 
124 	u32 seq, group;
125 };
126 
127 struct cn_dev {
128 	struct cb_id id;
129 
130 	u32 seq, groups;
131 	struct sock *nls;
132 	void (*input) (struct sk_buff *skb);
133 
134 	struct cn_queue_dev *cbdev;
135 };
136 
137 int cn_add_callback(struct cb_id *, char *, void (*callback) (struct cn_msg *, struct netlink_skb_parms *));
138 void cn_del_callback(struct cb_id *);
139 int cn_netlink_send(struct cn_msg *, u32, gfp_t);
140 
141 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 *));
142 void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id);
143 
144 int queue_cn_work(struct cn_callback_entry *cbq, struct work_struct *work);
145 
146 struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *);
147 void cn_queue_free_dev(struct cn_queue_dev *dev);
148 
149 int cn_cb_equal(struct cb_id *, struct cb_id *);
150 
151 void cn_queue_wrapper(struct work_struct *work);
152 
153 #endif				/* __KERNEL__ */
154 #endif				/* __CONNECTOR_H */
155