1 /*
2  * 	connector.h
3  *
4  * 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
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 #define CN_KVP_IDX			0x9	/* HyperV KVP */
46 
47 #define CN_NETLINK_USERS		9
48 
49 /*
50  * Maximum connector's message size.
51  */
52 #define CONNECTOR_MAX_MSG_SIZE		16384
53 
54 /*
55  * idx and val are unique identifiers which
56  * are used for message routing and
57  * must be registered in connector.h for in-kernel usage.
58  */
59 
60 struct cb_id {
61 	__u32 idx;
62 	__u32 val;
63 };
64 
65 struct cn_msg {
66 	struct cb_id id;
67 
68 	__u32 seq;
69 	__u32 ack;
70 
71 	__u16 len;		/* Length of the following data */
72 	__u16 flags;
73 	__u8 data[0];
74 };
75 
76 #ifdef __KERNEL__
77 
78 #include <asm/atomic.h>
79 
80 #include <linux/list.h>
81 #include <linux/workqueue.h>
82 
83 #include <net/sock.h>
84 
85 #define CN_CBQ_NAMELEN		32
86 
87 struct cn_queue_dev {
88 	atomic_t refcnt;
89 	unsigned char name[CN_CBQ_NAMELEN];
90 
91 	struct list_head queue_list;
92 	spinlock_t queue_lock;
93 
94 	struct sock *nls;
95 };
96 
97 struct cn_callback_id {
98 	unsigned char name[CN_CBQ_NAMELEN];
99 	struct cb_id id;
100 };
101 
102 struct cn_callback_entry {
103 	struct list_head callback_entry;
104 	atomic_t refcnt;
105 	struct cn_queue_dev *pdev;
106 
107 	struct cn_callback_id id;
108 	void (*callback) (struct cn_msg *, struct netlink_skb_parms *);
109 
110 	u32 seq, group;
111 };
112 
113 struct cn_dev {
114 	struct cb_id id;
115 
116 	u32 seq, groups;
117 	struct sock *nls;
118 	void (*input) (struct sk_buff *skb);
119 
120 	struct cn_queue_dev *cbdev;
121 };
122 
123 int cn_add_callback(struct cb_id *id, const char *name,
124 		    void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
125 void cn_del_callback(struct cb_id *);
126 int cn_netlink_send(struct cn_msg *, u32, gfp_t);
127 
128 int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name,
129 			  struct cb_id *id,
130 			  void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
131 void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id);
132 void cn_queue_release_callback(struct cn_callback_entry *);
133 
134 struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *);
135 void cn_queue_free_dev(struct cn_queue_dev *dev);
136 
137 int cn_cb_equal(struct cb_id *, struct cb_id *);
138 
139 #endif				/* __KERNEL__ */
140 #endif				/* __CONNECTOR_H */
141