summaryrefslogtreecommitdiff
path: root/fs/9p/trans_fd.c
blob: b7ffb98595881f31f0c40cb7b6d519ee3050c3ed (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
/*
 * linux/fs/9p/trans_fd.c
 *
 * File Descriptor Transport Layer
 *
 *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.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 of the License, 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:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/ipv6.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/un.h>
#include <asm/uaccess.h>
#include <linux/inet.h>
#include <linux/idr.h>
#include <linux/file.h>

#include "debug.h"
#include "v9fs.h"
#include "transport.h"

struct v9fs_trans_fd {
	struct file *in_file;
	struct file *out_file;
};

/**
 * v9fs_fd_recv - receive from a socket
 * @v9ses: session information
 * @v: buffer to receive data into
 * @len: size of receive buffer
 *
 */

static int v9fs_fd_recv(struct v9fs_transport *trans, void *v, int len)
{
	struct v9fs_trans_fd *ts = trans ? trans->priv : NULL;

	if (!trans || trans->status != Connected || !ts)
		return -EIO;

	return kernel_read(ts->in_file, ts->in_file->f_pos, v, len);
}

/**
 * v9fs_fd_send - send to a socket
 * @v9ses: session information
 * @v: buffer to send data from
 * @len: size of send buffer
 *
 */

static int v9fs_fd_send(struct v9fs_transport *trans, void *v, int len)
{
	struct v9fs_trans_fd *ts = trans ? trans->priv : NULL;
	mm_segment_t oldfs = get_fs();
	int ret = 0;

	if (!trans || trans->status != Connected || !ts)
		return -EIO;

	set_fs(get_ds());
	/* The cast to a user pointer is valid due to the set_fs() */
	ret = vfs_write(ts->out_file, (void __user *)v, len, &ts->out_file->f_pos);
	set_fs(oldfs);

	return ret;
}

/**
 * v9fs_fd_init - initialize file descriptor transport
 * @v9ses: session information
 * @addr: address of server to mount
 * @data: mount options
 *
 */

static int
v9fs_fd_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
{
	struct v9fs_trans_fd *ts = NULL;
	struct v9fs_transport *trans = v9ses->transport;

	if((v9ses->wfdno == ~0) || (v9ses->rfdno == ~0)) {
		printk(KERN_ERR "v9fs: Insufficient options for proto=fd\n");
		return -ENOPROTOOPT;
	}

	sema_init(&trans->writelock, 1);
	sema_init(&trans->readlock, 1);

	ts = kmalloc(sizeof(struct v9fs_trans_fd), GFP_KERNEL);

	if (!ts)
		return -ENOMEM;

	ts->in_file = fget( v9ses->rfdno );
	ts->out_file = fget( v9ses->wfdno );

	if (!ts->in_file || !ts->out_file) {
		if (ts->in_file)
			fput(ts->in_file);

		if (ts->out_file)
			fput(ts->out_file);

		kfree(ts);
		return -EIO;
	}

	trans->priv = ts;
	trans->status = Connected;

	return 0;
}


/**
 * v9fs_fd_close - shutdown file descriptor
 * @trans: private socket structure
 *
 */

static void v9fs_fd_close(struct v9fs_transport *trans)
{
	struct v9fs_trans_fd *ts;

	if (!trans)
		return;

	ts = xchg(&trans->priv, NULL);

	if (!ts)
		return;

	trans->status = Disconnected;
	if (ts->in_file)
		fput(ts->in_file);

	if (ts->out_file)
		fput(ts->out_file);

	kfree(ts);
}

struct v9fs_transport v9fs_trans_fd = {
	.init = v9fs_fd_init,
	.write = v9fs_fd_send,
	.read = v9fs_fd_recv,
	.close = v9fs_fd_close,
};