Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6] / drivers / s390 / net / smsgiucv.c
1 /*
2  * IUCV special message driver
3  *
4  * Copyright 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
5  * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
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, or (at your option)
10  * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/errno.h>
25 #include <linux/device.h>
26 #include <net/iucv/iucv.h>
27 #include <asm/cpcmd.h>
28 #include <asm/ebcdic.h>
29 #include "smsgiucv.h"
30
31 struct smsg_callback {
32         struct list_head list;
33         char *prefix;
34         int len;
35         void (*callback)(char *from, char *str);
36 };
37
38 MODULE_AUTHOR
39    ("(C) 2003 IBM Corporation by Martin Schwidefsky (schwidefsky@de.ibm.com)");
40 MODULE_DESCRIPTION ("Linux for S/390 IUCV special message driver");
41
42 static struct iucv_path *smsg_path;
43
44 static DEFINE_SPINLOCK(smsg_list_lock);
45 static LIST_HEAD(smsg_list);
46
47 static int smsg_path_pending(struct iucv_path *, u8 ipvmid[8], u8 ipuser[16]);
48 static void smsg_message_pending(struct iucv_path *, struct iucv_message *);
49
50 static struct iucv_handler smsg_handler = {
51         .path_pending    = smsg_path_pending,
52         .message_pending = smsg_message_pending,
53 };
54
55 static int smsg_path_pending(struct iucv_path *path, u8 ipvmid[8],
56                              u8 ipuser[16])
57 {
58         if (strncmp(ipvmid, "*MSG    ", sizeof(ipvmid)) != 0)
59                 return -EINVAL;
60         /* Path pending from *MSG. */
61         return iucv_path_accept(path, &smsg_handler, "SMSGIUCV        ", NULL);
62 }
63
64 static void smsg_message_pending(struct iucv_path *path,
65                                  struct iucv_message *msg)
66 {
67         struct smsg_callback *cb;
68         unsigned char *buffer;
69         unsigned char sender[9];
70         int rc, i;
71
72         buffer = kmalloc(msg->length + 1, GFP_ATOMIC | GFP_DMA);
73         if (!buffer) {
74                 iucv_message_reject(path, msg);
75                 return;
76         }
77         rc = iucv_message_receive(path, msg, 0, buffer, msg->length, NULL);
78         if (rc == 0) {
79                 buffer[msg->length] = 0;
80                 EBCASC(buffer, msg->length);
81                 memcpy(sender, buffer, 8);
82                 sender[8] = 0;
83                 /* Remove trailing whitespace from the sender name. */
84                 for (i = 7; i >= 0; i--) {
85                         if (sender[i] != ' ' && sender[i] != '\t')
86                                 break;
87                         sender[i] = 0;
88                 }
89                 spin_lock(&smsg_list_lock);
90                 list_for_each_entry(cb, &smsg_list, list)
91                         if (strncmp(buffer + 8, cb->prefix, cb->len) == 0) {
92                                 cb->callback(sender, buffer + 8);
93                                 break;
94                         }
95                 spin_unlock(&smsg_list_lock);
96         }
97         kfree(buffer);
98 }
99
100 int smsg_register_callback(char *prefix,
101                            void (*callback)(char *from, char *str))
102 {
103         struct smsg_callback *cb;
104
105         cb = kmalloc(sizeof(struct smsg_callback), GFP_KERNEL);
106         if (!cb)
107                 return -ENOMEM;
108         cb->prefix = prefix;
109         cb->len = strlen(prefix);
110         cb->callback = callback;
111         spin_lock_bh(&smsg_list_lock);
112         list_add_tail(&cb->list, &smsg_list);
113         spin_unlock_bh(&smsg_list_lock);
114         return 0;
115 }
116
117 void smsg_unregister_callback(char *prefix,
118                               void (*callback)(char *from, char *str))
119 {
120         struct smsg_callback *cb, *tmp;
121
122         spin_lock_bh(&smsg_list_lock);
123         cb = NULL;
124         list_for_each_entry(tmp, &smsg_list, list)
125                 if (tmp->callback == callback &&
126                     strcmp(tmp->prefix, prefix) == 0) {
127                         cb = tmp;
128                         list_del(&cb->list);
129                         break;
130                 }
131         spin_unlock_bh(&smsg_list_lock);
132         kfree(cb);
133 }
134
135 static struct device_driver smsg_driver = {
136         .name = "SMSGIUCV",
137         .bus  = &iucv_bus,
138 };
139
140 static void __exit smsg_exit(void)
141 {
142         cpcmd("SET SMSG IUCV", NULL, 0, NULL);
143         iucv_unregister(&smsg_handler, 1);
144         driver_unregister(&smsg_driver);
145 }
146
147 static int __init smsg_init(void)
148 {
149         int rc;
150
151         if (!MACHINE_IS_VM) {
152                 rc = -EPROTONOSUPPORT;
153                 goto out;
154         }
155         rc = driver_register(&smsg_driver);
156         if (rc != 0)
157                 goto out;
158         rc = iucv_register(&smsg_handler, 1);
159         if (rc)
160                 goto out_driver;
161         smsg_path = iucv_path_alloc(255, 0, GFP_KERNEL);
162         if (!smsg_path) {
163                 rc = -ENOMEM;
164                 goto out_register;
165         }
166         rc = iucv_path_connect(smsg_path, &smsg_handler, "*MSG    ",
167                                NULL, NULL, NULL);
168         if (rc)
169                 goto out_free;
170         cpcmd("SET SMSG IUCV", NULL, 0, NULL);
171         return 0;
172
173 out_free:
174         iucv_path_free(smsg_path);
175 out_register:
176         iucv_unregister(&smsg_handler, 1);
177 out_driver:
178         driver_unregister(&smsg_driver);
179 out:
180         return rc;
181 }
182
183 module_init(smsg_init);
184 module_exit(smsg_exit);
185 MODULE_LICENSE("GPL");
186
187 EXPORT_SYMBOL(smsg_register_callback);
188 EXPORT_SYMBOL(smsg_unregister_callback);