summaryrefslogtreecommitdiffstats
path: root/drivers/s390/net/smsgiucv.c
blob: 207b7d7424435ccefd62700a07cd424a0e732c40 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
/*
 * IUCV special message driver
 *
 * Copyright IBM Corp. 2003, 2009
 *
 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <net/iucv/iucv.h>
#include <asm/cpcmd.h>
#include <asm/ebcdic.h>
#include "smsgiucv.h"

struct smsg_callback {
	struct list_head list;
	const char *prefix;
	int len;
	void (*callback)(const char *from, char *str);
};

MODULE_AUTHOR
   ("(C) 2003 IBM Corporation by Martin Schwidefsky (schwidefsky@de.ibm.com)");
MODULE_DESCRIPTION ("Linux for S/390 IUCV special message driver");

static struct iucv_path *smsg_path;
/* dummy device used as trigger for PM functions */
static struct device *smsg_dev;

static DEFINE_SPINLOCK(smsg_list_lock);
static LIST_HEAD(smsg_list);
static int iucv_path_connected;

static int smsg_path_pending(struct iucv_path *, u8 ipvmid[8], u8 ipuser[16]);
static void smsg_message_pending(struct iucv_path *, struct iucv_message *);

static struct iucv_handler smsg_handler = {
	.path_pending	 = smsg_path_pending,
	.message_pending = smsg_message_pending,
};

static int smsg_path_pending(struct iucv_path *path, u8 ipvmid[8],
			     u8 ipuser[16])
{
	if (strncmp(ipvmid, "*MSG    ", 8) != 0)
		return -EINVAL;
	/* Path pending from *MSG. */
	return iucv_path_accept(path, &smsg_handler, "SMSGIUCV        ", NULL);
}

static void smsg_message_pending(struct iucv_path *path,
				 struct iucv_message *msg)
{
	struct smsg_callback *cb;
	unsigned char *buffer;
	unsigned char sender[9];
	int rc, i;

	buffer = kmalloc(msg->length + 1, GFP_ATOMIC | GFP_DMA);
	if (!buffer) {
		iucv_message_reject(path, msg);
		return;
	}
	rc = iucv_message_receive(path, msg, 0, buffer, msg->length, NULL);
	if (rc == 0) {
		buffer[msg->length] = 0;
		EBCASC(buffer, msg->length);
		memcpy(sender, buffer, 8);
		sender[8] = 0;
		/* Remove trailing whitespace from the sender name. */
		for (i = 7; i >= 0; i--) {
			if (sender[i] != ' ' && sender[i] != '\t')
				break;
			sender[i] = 0;
		}
		spin_lock(&smsg_list_lock);
		list_for_each_entry(cb, &smsg_list, list)
			if (strncmp(buffer + 8, cb->prefix, cb->len) == 0) {
				cb->callback(sender, buffer + 8);
				break;
			}
		spin_unlock(&smsg_list_lock);
	}
	kfree(buffer);
}

int smsg_register_callback(const char *prefix,
			   void (*callback)(const char *from, char *str))
{
	struct smsg_callback *cb;

	cb = kmalloc(sizeof(struct smsg_callback), GFP_KERNEL);
	if (!cb)
		return -ENOMEM;
	cb->prefix = prefix;
	cb->len = strlen(prefix);
	cb->callback = callback;
	spin_lock_bh(&smsg_list_lock);
	list_add_tail(&cb->list, &smsg_list);
	spin_unlock_bh(&smsg_list_lock);
	return 0;
}

void smsg_unregister_callback(const char *prefix,
			      void (*callback)(const char *from,
					       char *str))
{
	struct smsg_callback *cb, *tmp;

	spin_lock_bh(&smsg_list_lock);
	cb = NULL;
	list_for_each_entry(tmp, &smsg_list, list)
		if (tmp->callback == callback &&
		    strcmp(tmp->prefix, prefix) == 0) {
			cb = tmp;
			list_del(&cb->list);
			break;
		}
	spin_unlock_bh(&smsg_list_lock);
	kfree(cb);
}

static int smsg_pm_freeze(struct device *dev)
{
#ifdef CONFIG_PM_DEBUG
	printk(KERN_WARNING "smsg_pm_freeze\n");
#endif
	if (smsg_path && iucv_path_connected) {
		iucv_path_sever(smsg_path, NULL);
		iucv_path_connected = 0;
	}
	return 0;
}

static int smsg_pm_restore_thaw(struct device *dev)
{
	int rc;

#ifdef CONFIG_PM_DEBUG
	printk(KERN_WARNING "smsg_pm_restore_thaw\n");
#endif
	if (smsg_path && iucv_path_connected) {
		memset(smsg_path, 0, sizeof(*smsg_path));
		smsg_path->msglim = 255;
		smsg_path->flags = 0;
		rc = iucv_path_connect(smsg_path, &smsg_handler, "*MSG    ",
				       NULL, NULL, NULL);
#ifdef CONFIG_PM_DEBUG
		if (rc)
			printk(KERN_ERR
			       "iucv_path_connect returned with rc %i\n", rc);
#endif
		if (!rc)
			iucv_path_connected = 1;
		cpcmd("SET SMSG IUCV", NULL, 0, NULL);
	}
	return 0;
}

static const struct dev_pm_ops smsg_pm_ops = {
	.freeze = smsg_pm_freeze,
	.thaw = smsg_pm_restore_thaw,
	.restore = smsg_pm_restore_thaw,
};

static struct device_driver smsg_driver = {
	.owner = THIS_MODULE,
	.name = SMSGIUCV_DRV_NAME,
	.bus  = &iucv_bus,
	.pm = &smsg_pm_ops,
};

static void __exit smsg_exit(void)
{
	cpcmd("SET SMSG IUCV", NULL, 0, NULL);
	device_unregister(smsg_dev);
	iucv_unregister(&smsg_handler, 1);
	driver_unregister(&smsg_driver);
}

static int __init smsg_init(void)
{
	int rc;

	if (!MACHINE_IS_VM) {
		rc = -EPROTONOSUPPORT;
		goto out;
	}
	rc = driver_register(&smsg_driver);
	if (rc != 0)
		goto out;
	rc = iucv_register(&smsg_handler, 1);
	if (rc)
		goto out_driver;
	smsg_path = iucv_path_alloc(255, 0, GFP_KERNEL);
	if (!smsg_path) {
		rc = -ENOMEM;
		goto out_register;
	}
	rc = iucv_path_connect(smsg_path, &smsg_handler, "*MSG    ",
			       NULL, NULL, NULL);
	if (rc)
		goto out_free_path;
	else
		iucv_path_connected = 1;
	smsg_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
	if (!smsg_dev) {
		rc = -ENOMEM;
		goto out_free_path;
	}
	dev_set_name(smsg_dev, "smsg_iucv");
	smsg_dev->bus = &iucv_bus;
	smsg_dev->parent = iucv_root;
	smsg_dev->release = (void (*)(struct device *))kfree;
	smsg_dev->driver = &smsg_driver;
	rc = device_register(smsg_dev);
	if (rc)
		goto out_put;

	cpcmd("SET SMSG IUCV", NULL, 0, NULL);
	return 0;

out_put:
	put_device(smsg_dev);
out_free_path:
	iucv_path_free(smsg_path);
	smsg_path = NULL;
out_register:
	iucv_unregister(&smsg_handler, 1);
out_driver:
	driver_unregister(&smsg_driver);
out:
	return rc;
}

module_init(smsg_init);
module_exit(smsg_exit);
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(smsg_register_callback);
EXPORT_SYMBOL(smsg_unregister_callback);