stdio_console.c revision e4dcee8099802c71437a15b940f66106d9f88b2f 
1/*
2 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6#include "linux/config.h"
7#include "linux/posix_types.h"
8#include "linux/tty.h"
9#include "linux/tty_flip.h"
10#include "linux/types.h"
11#include "linux/major.h"
12#include "linux/kdev_t.h"
13#include "linux/console.h"
14#include "linux/string.h"
15#include "linux/sched.h"
16#include "linux/list.h"
17#include "linux/init.h"
18#include "linux/interrupt.h"
19#include "linux/slab.h"
20#include "linux/hardirq.h"
21#include "asm/current.h"
22#include "asm/irq.h"
23#include "stdio_console.h"
24#include "line.h"
25#include "chan_kern.h"
26#include "user_util.h"
27#include "kern_util.h"
28#include "irq_user.h"
29#include "mconsole_kern.h"
30#include "init.h"
31
32#define MAX_TTYS (16)
33
34/* ----------------------------------------------------------------------------- */
35
36/* Referenced only by tty_driver below - presumably it's locked correctly
37 * by the tty driver.
38 */
39
40static struct tty_driver *console_driver;
41
42void stdio_announce(char *dev_name, int dev)
43{
44	printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
45	       dev_name);
46}
47
48static struct chan_opts opts = {
49	.announce 	= stdio_announce,
50	.xterm_title	= "Virtual Console #%d",
51	.raw		= 1,
52	.tramp_stack 	= 0,
53	.in_kernel 	= 1,
54};
55
56static int con_config(char *str);
57static int con_get_config(char *dev, char *str, int size, char **error_out);
58static int con_remove(int n);
59
60static struct line_driver driver = {
61	.name 			= "UML console",
62	.device_name 		= "tty",
63	.devfs_name 		= "vc/",
64	.major 			= TTY_MAJOR,
65	.minor_start 		= 0,
66	.type 		 	= TTY_DRIVER_TYPE_CONSOLE,
67	.subtype 	 	= SYSTEM_TYPE_CONSOLE,
68	.read_irq 		= CONSOLE_IRQ,
69	.read_irq_name 		= "console",
70	.write_irq 		= CONSOLE_WRITE_IRQ,
71	.write_irq_name 	= "console-write",
72	.symlink_from 		= "ttys",
73	.symlink_to 		= "vc",
74	.mc  = {
75		.name  		= "con",
76		.config 	= con_config,
77		.get_config 	= con_get_config,
78		.id		= line_id,
79		.remove 	= con_remove,
80	},
81};
82
83static struct lines console_lines = LINES_INIT(MAX_TTYS);
84
85/* The array is initialized by line_init, which is an initcall.  The
86 * individual elements are protected by individual semaphores.
87 */
88struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
89			      [ 1 ... MAX_TTYS - 1 ] =
90			      LINE_INIT(CONFIG_CON_CHAN, &driver) };
91
92static int con_config(char *str)
93{
94	return line_config(vts, ARRAY_SIZE(vts), str, &opts);
95}
96
97static int con_get_config(char *dev, char *str, int size, char **error_out)
98{
99	return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
100}
101
102static int con_remove(int n)
103{
104	return line_remove(vts, ARRAY_SIZE(vts), n);
105}
106
107static int con_open(struct tty_struct *tty, struct file *filp)
108{
109	return line_open(vts, tty);
110}
111
112static int con_init_done = 0;
113
114static struct tty_operations console_ops = {
115	.open 	 		= con_open,
116	.close 	 		= line_close,
117	.write 	 		= line_write,
118	.put_char 		= line_put_char,
119	.write_room		= line_write_room,
120	.chars_in_buffer 	= line_chars_in_buffer,
121	.flush_buffer 		= line_flush_buffer,
122	.flush_chars 		= line_flush_chars,
123	.set_termios 		= line_set_termios,
124	.ioctl 	 		= line_ioctl,
125	.throttle 		= line_throttle,
126	.unthrottle 		= line_unthrottle,
127};
128
129static void uml_console_write(struct console *console, const char *string,
130			      unsigned len)
131{
132	struct line *line = &vts[console->index];
133	unsigned long flags;
134
135	spin_lock_irqsave(&line->lock, flags);
136	console_write_chan(&line->chan_list, string, len);
137	spin_unlock_irqrestore(&line->lock, flags);
138}
139
140static struct tty_driver *uml_console_device(struct console *c, int *index)
141{
142	*index = c->index;
143	return console_driver;
144}
145
146static int uml_console_setup(struct console *co, char *options)
147{
148	struct line *line = &vts[co->index];
149
150	return console_open_chan(line, co, &opts);
151}
152
153static struct console stdiocons = {
154	.name		= "tty",
155	.write		= uml_console_write,
156	.device		= uml_console_device,
157	.setup		= uml_console_setup,
158	.flags		= CON_PRINTBUFFER,
159	.index		= -1,
160	.data		= &vts,
161};
162
163int stdio_init(void)
164{
165	char *new_title;
166
167	console_driver = line_register_devfs(&console_lines, &driver,
168					     &console_ops, vts,
169					     ARRAY_SIZE(vts));
170	if (console_driver == NULL)
171		return -1;
172	printk(KERN_INFO "Initialized stdio console driver\n");
173
174	lines_init(vts, ARRAY_SIZE(vts), &opts);
175
176	new_title = add_xterm_umid(opts.xterm_title);
177	if(new_title != NULL)
178		opts.xterm_title = new_title;
179
180	con_init_done = 1;
181	register_console(&stdiocons);
182	return 0;
183}
184late_initcall(stdio_init);
185
186static void console_exit(void)
187{
188	if (!con_init_done)
189		return;
190	close_lines(vts, ARRAY_SIZE(vts));
191}
192__uml_exitcall(console_exit);
193
194static int console_chan_setup(char *str)
195{
196	return line_setup(vts, ARRAY_SIZE(vts), str);
197}
198__setup("con", console_chan_setup);
199__channel_help(console_chan_setup, "con");
200