summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/stdio_console.c
blob: 088776f01908e2eb5a27281cbac37b5927012881 (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
/* 
 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include "linux/posix_types.h"
#include "linux/tty.h"
#include "linux/tty_flip.h"
#include "linux/types.h"
#include "linux/major.h"
#include "linux/kdev_t.h"
#include "linux/console.h"
#include "linux/string.h"
#include "linux/sched.h"
#include "linux/list.h"
#include "linux/init.h"
#include "linux/interrupt.h"
#include "linux/slab.h"
#include "linux/hardirq.h"
#include "asm/current.h"
#include "asm/irq.h"
#include "stdio_console.h"
#include "chan.h"
#include "irq_user.h"
#include "mconsole_kern.h"
#include "init.h"

#define MAX_TTYS (16)

/* Referenced only by tty_driver below - presumably it's locked correctly
 * by the tty driver.
 */

static struct tty_driver *console_driver;

static void stdio_announce(char *dev_name, int dev)
{
	printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
	       dev_name);
}

/* Almost const, except that xterm_title may be changed in an initcall */
static struct chan_opts opts = {
	.announce 	= stdio_announce,
	.xterm_title	= "Virtual Console #%d",
	.raw		= 1,
};

static int con_config(char *str, char **error_out);
static int con_get_config(char *dev, char *str, int size, char **error_out);
static int con_remove(int n, char **con_remove);


/* Const, except for .mc.list */
static struct line_driver driver = {
	.name 			= "UML console",
	.device_name 		= "tty",
	.major 			= TTY_MAJOR,
	.minor_start 		= 0,
	.type 		 	= TTY_DRIVER_TYPE_CONSOLE,
	.subtype 	 	= SYSTEM_TYPE_CONSOLE,
	.read_irq 		= CONSOLE_IRQ,
	.read_irq_name 		= "console",
	.write_irq 		= CONSOLE_WRITE_IRQ,
	.write_irq_name 	= "console-write",
	.mc  = {
		.list		= LIST_HEAD_INIT(driver.mc.list),
		.name  		= "con",
		.config 	= con_config,
		.get_config 	= con_get_config,
		.id		= line_id,
		.remove 	= con_remove,
	},
};

/* The array is initialized by line_init, at initcall time.  The
 * elements are locked individually as needed.
 */
static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
				     [ 1 ... MAX_TTYS - 1 ] =
				     LINE_INIT(CONFIG_CON_CHAN, &driver) };

static int con_config(char *str, char **error_out)
{
	return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out);
}

static int con_get_config(char *dev, char *str, int size, char **error_out)
{
	return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
}

static int con_remove(int n, char **error_out)
{
	return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
}

static int con_open(struct tty_struct *tty, struct file *filp)
{
	int err = line_open(vts, tty);
	if (err)
		printk(KERN_ERR "Failed to open console %d, err = %d\n",
		       tty->index, err);

	return err;
}

/* Set in an initcall, checked in an exitcall */
static int con_init_done = 0;

static const struct tty_operations console_ops = {
	.open 	 		= con_open,
	.close 	 		= line_close,
	.write 	 		= line_write,
	.put_char 		= line_put_char,
	.write_room		= line_write_room,
	.chars_in_buffer 	= line_chars_in_buffer,
	.flush_buffer 		= line_flush_buffer,
	.flush_chars 		= line_flush_chars,
	.set_termios 		= line_set_termios,
	.ioctl 	 		= line_ioctl,
	.throttle 		= line_throttle,
	.unthrottle 		= line_unthrottle,
};

static void uml_console_write(struct console *console, const char *string,
			      unsigned len)
{
	struct line *line = &vts[console->index];
	unsigned long flags;

	spin_lock_irqsave(&line->lock, flags);
	console_write_chan(&line->chan_list, string, len);
	spin_unlock_irqrestore(&line->lock, flags);
}

static struct tty_driver *uml_console_device(struct console *c, int *index)
{
	*index = c->index;
	return console_driver;
}

static int uml_console_setup(struct console *co, char *options)
{
	struct line *line = &vts[co->index];

	return console_open_chan(line, co);
}

/* No locking for register_console call - relies on single-threaded initcalls */
static struct console stdiocons = {
	.name		= "tty",
	.write		= uml_console_write,
	.device		= uml_console_device,
	.setup		= uml_console_setup,
	.flags		= CON_PRINTBUFFER|CON_ANYTIME,
	.index		= -1,
};

static int stdio_init(void)
{
	char *new_title;

	console_driver = register_lines(&driver, &console_ops, vts,
					ARRAY_SIZE(vts));
	if (console_driver == NULL)
		return -1;
	printk(KERN_INFO "Initialized stdio console driver\n");

	new_title = add_xterm_umid(opts.xterm_title);
	if(new_title != NULL)
		opts.xterm_title = new_title;

	lines_init(vts, ARRAY_SIZE(vts), &opts);

	con_init_done = 1;
	register_console(&stdiocons);
	return 0;
}
late_initcall(stdio_init);

static void console_exit(void)
{
	if (!con_init_done)
		return;
	close_lines(vts, ARRAY_SIZE(vts));
}
__uml_exitcall(console_exit);

static int console_chan_setup(char *str)
{
	char *error;
	int ret;

	ret = line_setup(vts, ARRAY_SIZE(vts), str, &error);
	if(ret < 0)
		printk(KERN_ERR "Failed to set up console with "
		       "configuration string \"%s\" : %s\n", str, error);

	return 1;
}
__setup("con", console_chan_setup);
__channel_help(console_chan_setup, "con");