summaryrefslogtreecommitdiffstats
path: root/net/9p/mod.c
blob: c1b62428da7bd98588dd250ba98483304f901683 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 *  net/9p/9p.c
 *
 *  9P entry point
 *
 *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/moduleparam.h>
#include <net/9p/9p.h>
#include <linux/fs.h>
#include <linux/parser.h>
#include <net/9p/client.h>
#include <net/9p/transport.h>
#include <linux/list.h>
#include <linux/spinlock.h>

#ifdef CONFIG_NET_9P_DEBUG
unsigned int p9_debug_level = 0;	/* feature-rific global debug level  */
EXPORT_SYMBOL(p9_debug_level);
module_param_named(debug, p9_debug_level, uint, 0);
MODULE_PARM_DESC(debug, "9P debugging level");

void _p9_debug(enum p9_debug_flags level, const char *func,
		const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;

	if ((p9_debug_level & level) != level)
		return;

	va_start(args, fmt);

	vaf.fmt = fmt;
	vaf.va = &args;

	if (level == P9_DEBUG_9P)
		pr_notice("(%8.8d) %pV", task_pid_nr(current), &vaf);
	else
		pr_notice("-- %s (%d): %pV", func, task_pid_nr(current), &vaf);

	va_end(args);
}
EXPORT_SYMBOL(_p9_debug);
#endif

/*
 * Dynamic Transport Registration Routines
 *
 */

static DEFINE_SPINLOCK(v9fs_trans_lock);
static LIST_HEAD(v9fs_trans_list);

/**
 * v9fs_register_trans - register a new transport with 9p
 * @m: structure describing the transport module and entry points
 *
 */
void v9fs_register_trans(struct p9_trans_module *m)
{
	spin_lock(&v9fs_trans_lock);
	list_add_tail(&m->list, &v9fs_trans_list);
	spin_unlock(&v9fs_trans_lock);
}
EXPORT_SYMBOL(v9fs_register_trans);

/**
 * v9fs_unregister_trans - unregister a 9p transport
 * @m: the transport to remove
 *
 */
void v9fs_unregister_trans(struct p9_trans_module *m)
{
	spin_lock(&v9fs_trans_lock);
	list_del_init(&m->list);
	spin_unlock(&v9fs_trans_lock);
}
EXPORT_SYMBOL(v9fs_unregister_trans);

/**
 * v9fs_get_trans_by_name - get transport with the matching name
 * @s: string identifying transport
 *
 */
struct p9_trans_module *v9fs_get_trans_by_name(char *s)
{
	struct p9_trans_module *t, *found = NULL;

	spin_lock(&v9fs_trans_lock);

	list_for_each_entry(t, &v9fs_trans_list, list)
		if (strcmp(t->name, s) == 0 &&
		    try_module_get(t->owner)) {
			found = t;
			break;
		}

	spin_unlock(&v9fs_trans_lock);
	return found;
}
EXPORT_SYMBOL(v9fs_get_trans_by_name);

/**
 * v9fs_get_default_trans - get the default transport
 *
 */

struct p9_trans_module *v9fs_get_default_trans(void)
{
	struct p9_trans_module *t, *found = NULL;

	spin_lock(&v9fs_trans_lock);

	list_for_each_entry(t, &v9fs_trans_list, list)
		if (t->def && try_module_get(t->owner)) {
			found = t;
			break;
		}

	if (!found)
		list_for_each_entry(t, &v9fs_trans_list, list)
			if (try_module_get(t->owner)) {
				found = t;
				break;
			}

	spin_unlock(&v9fs_trans_lock);
	return found;
}
EXPORT_SYMBOL(v9fs_get_default_trans);

/**
 * v9fs_put_trans - put trans
 * @m: transport to put
 *
 */
void v9fs_put_trans(struct p9_trans_module *m)
{
	if (m)
		module_put(m->owner);
}

/**
 * init_p9 - Initialize module
 *
 */
static int __init init_p9(void)
{
	int ret;

	ret = p9_client_init();
	if (ret)
		return ret;

	p9_error_init();
	pr_info("Installing 9P2000 support\n");
	p9_trans_fd_init();

	return ret;
}

/**
 * exit_p9 - shutdown module
 *
 */

static void __exit exit_p9(void)
{
	pr_info("Unloading 9P2000 support\n");

	p9_trans_fd_exit();
	p9_client_exit();
}

module_init(init_p9)
module_exit(exit_p9)

MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud