stdio_console.c revision 04292b2cf8f02a33cfc1054c0c51aa8c77731813 
1/*
2 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6#include "linux/posix_types.h"
7#include "linux/tty.h"
8#include "linux/tty_flip.h"
9#include "linux/types.h"
10#include "linux/major.h"
11#include "linux/kdev_t.h"
12#include "linux/console.h"
13#include "linux/string.h"
14#include "linux/sched.h"
15#include "linux/list.h"
16#include "linux/init.h"
17#include "linux/interrupt.h"
18#include "linux/slab.h"
19#include "linux/hardirq.h"
20#include "asm/current.h"
21#include "asm/irq.h"
22#include "stdio_console.h"
23#include "chan.h"
24#include "irq_user.h"
25#include "mconsole_kern.h"
26#include "init.h"
27
28#define MAX_TTYS (16)
29
30static void stdio_announce(char *dev_name, int dev)
31{
32	printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
33	       dev_name);
34}
35
36/* Almost const, except that xterm_title may be changed in an initcall */
37static struct chan_opts opts = {
38	.announce 	= stdio_announce,
39	.xterm_title	= "Virtual Console #%d",
40	.raw		= 1,
41};
42
43static int con_config(char *str, char **error_out);
44static int con_get_config(char *dev, char *str, int size, char **error_out);
45static int con_remove(int n, char **con_remove);
46
47
48/* Const, except for .mc.list */
49static struct line_driver driver = {
50	.name 			= "UML console",
51	.device_name 		= "tty",
52	.major 			= TTY_MAJOR,
53	.minor_start 		= 0,
54	.type 		 	= TTY_DRIVER_TYPE_CONSOLE,
55	.subtype 	 	= SYSTEM_TYPE_CONSOLE,
56	.read_irq 		= CONSOLE_IRQ,
57	.read_irq_name 		= "console",
58	.write_irq 		= CONSOLE_WRITE_IRQ,
59	.write_irq_name 	= "console-write",
60	.mc  = {
61		.list		= LIST_HEAD_INIT(driver.mc.list),
62		.name  		= "con",
63		.config 	= con_config,
64		.get_config 	= con_get_config,
65		.id		= line_id,
66		.remove 	= con_remove,
67	},
68};
69
70/* The array is initialized by line_init, at initcall time.  The
71 * elements are locked individually as needed.
72 */
73static char *vt_conf[MAX_TTYS];
74static char *def_conf;
75static struct line vts[MAX_TTYS];
76
77static int con_config(char *str, char **error_out)
78{
79	return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out);
80}
81
82static int con_get_config(char *dev, char *str, int size, char **error_out)
83{
84	return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
85}
86
87static int con_remove(int n, char **error_out)
88{
89	return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
90}
91
92static int con_open(struct tty_struct *tty, struct file *filp)
93{
94	int err = line_open(vts, tty);
95	if (err)
96		printk(KERN_ERR "Failed to open console %d, err = %d\n",
97		       tty->index, err);
98
99	return err;
100}
101
102/* Set in an initcall, checked in an exitcall */
103static int con_init_done = 0;
104
105static const struct tty_operations console_ops = {
106	.open 	 		= con_open,
107	.close 	 		= line_close,
108	.write 	 		= line_write,
109	.put_char 		= line_put_char,
110	.write_room		= line_write_room,
111	.chars_in_buffer 	= line_chars_in_buffer,
112	.flush_buffer 		= line_flush_buffer,
113	.flush_chars 		= line_flush_chars,
114	.set_termios 		= line_set_termios,
115	.ioctl 	 		= line_ioctl,
116	.throttle 		= line_throttle,
117	.unthrottle 		= line_unthrottle,
118};
119
120static void uml_console_write(struct console *console, const char *string,
121			      unsigned len)
122{
123	struct line *line = &vts[console->index];
124	unsigned long flags;
125
126	spin_lock_irqsave(&line->lock, flags);
127	console_write_chan(&line->chan_list, string, len);
128	spin_unlock_irqrestore(&line->lock, flags);
129}
130
131static struct tty_driver *uml_console_device(struct console *c, int *index)
132{
133	*index = c->index;
134	return driver.driver;
135}
136
137static int uml_console_setup(struct console *co, char *options)
138{
139	struct line *line = &vts[co->index];
140
141	return console_open_chan(line, co);
142}
143
144/* No locking for register_console call - relies on single-threaded initcalls */
145static struct console stdiocons = {
146	.name		= "tty",
147	.write		= uml_console_write,
148	.device		= uml_console_device,
149	.setup		= uml_console_setup,
150	.flags		= CON_PRINTBUFFER|CON_ANYTIME,
151	.index		= -1,
152};
153
154static int stdio_init(void)
155{
156	char *new_title;
157	int err;
158	int i;
159
160	err = register_lines(&driver, &console_ops, vts,
161					ARRAY_SIZE(vts));
162	if (err)
163		return err;
164
165	printk(KERN_INFO "Initialized stdio console driver\n");
166
167	new_title = add_xterm_umid(opts.xterm_title);
168	if(new_title != NULL)
169		opts.xterm_title = new_title;
170
171	for (i = 0; i < MAX_TTYS; i++) {
172		char *error;
173		char *s = vt_conf[i];
174		if (!s)
175			s = def_conf;
176		if (!s)
177			s = i ? CONFIG_CON_CHAN : CONFIG_CON_ZERO_CHAN;
178		if (setup_one_line(vts, i, s, &opts, &error))
179			printk(KERN_ERR "setup_one_line failed for "
180			       "device %d : %s\n", i, error);
181	}
182
183	con_init_done = 1;
184	register_console(&stdiocons);
185	return 0;
186}
187late_initcall(stdio_init);
188
189static void console_exit(void)
190{
191	if (!con_init_done)
192		return;
193	close_lines(vts, ARRAY_SIZE(vts));
194}
195__uml_exitcall(console_exit);
196
197static int console_chan_setup(char *str)
198{
199	line_setup(vt_conf, MAX_TTYS, &def_conf, str, "console");
200	return 1;
201}
202__setup("con", console_chan_setup);
203__channel_help(console_chan_setup, "con");
204