[PATCH] uml: hot-unplug code cleanup
[linux-2.6.git] / arch / um / drivers / stdio_console.c
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
40 static struct tty_driver *console_driver;
41
42 void 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
48 static 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
56 static int con_config(char *str);
57 static int con_get_config(char *dev, char *str, int size, char **error_out);
58 static int con_remove(int n);
59
60 static 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
83 static 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  */
88 struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
89                               [ 1 ... MAX_TTYS - 1 ] = 
90                               LINE_INIT(CONFIG_CON_CHAN, &driver) };
91
92 static int con_config(char *str)
93 {
94         return(line_config(vts, sizeof(vts)/sizeof(vts[0]), str));
95 }
96
97 static int con_get_config(char *dev, char *str, int size, char **error_out)
98 {
99         return(line_get_config(dev, vts, sizeof(vts)/sizeof(vts[0]), str, 
100                                size, error_out));
101 }
102
103 static int con_remove(int n)
104 {
105         return line_remove(vts, sizeof(vts)/sizeof(vts[0]), n);
106 }
107
108 static int con_open(struct tty_struct *tty, struct file *filp)
109 {
110         return line_open(vts, tty, &opts);
111 }
112
113 static int con_init_done = 0;
114
115 static struct tty_operations console_ops = {
116         .open                   = con_open,
117         .close                  = line_close,
118         .write                  = line_write,
119         .put_char               = line_put_char,
120         .write_room             = line_write_room,
121         .chars_in_buffer        = line_chars_in_buffer,
122         .flush_buffer           = line_flush_buffer,
123         .flush_chars            = line_flush_chars,
124         .set_termios            = line_set_termios,
125         .ioctl                  = line_ioctl,
126 };
127
128 static void uml_console_write(struct console *console, const char *string,
129                           unsigned len)
130 {
131         struct line *line = &vts[console->index];
132         unsigned long flags;
133
134         spin_lock_irqsave(&line->lock, flags);
135         console_write_chan(&line->chan_list, string, len);
136         spin_unlock_irqrestore(&line->lock, flags);
137 }
138
139 static struct tty_driver *uml_console_device(struct console *c, int *index)
140 {
141         *index = c->index;
142         return console_driver;
143 }
144
145 static int uml_console_setup(struct console *co, char *options)
146 {
147         struct line *line = &vts[co->index];
148
149         return console_open_chan(line,co,&opts);
150 }
151
152 static struct console stdiocons = {
153         .name           = "tty",
154         .write          = uml_console_write,
155         .device         = uml_console_device,
156         .setup          = uml_console_setup,
157         .flags          = CON_PRINTBUFFER,
158         .index          = -1,
159         .data           = &vts,
160 };
161
162 int stdio_init(void)
163 {
164         char *new_title;
165
166         console_driver = line_register_devfs(&console_lines, &driver,
167                                              &console_ops, vts,
168                                              ARRAY_SIZE(vts));
169         if (NULL == console_driver)
170                 return -1;
171         printk(KERN_INFO "Initialized stdio console driver\n");
172
173         lines_init(vts, sizeof(vts)/sizeof(vts[0]));
174
175         new_title = add_xterm_umid(opts.xterm_title);
176         if(new_title != NULL)
177                 opts.xterm_title = new_title;
178
179         con_init_done = 1;
180         register_console(&stdiocons);
181         return(0);
182 }
183 late_initcall(stdio_init);
184
185 static void console_exit(void)
186 {
187         if (!con_init_done)
188                 return;
189         close_lines(vts, sizeof(vts)/sizeof(vts[0]));
190 }
191 __uml_exitcall(console_exit);
192
193 static int console_chan_setup(char *str)
194 {
195         return(line_setup(vts, sizeof(vts)/sizeof(vts[0]), str, 1));
196 }
197 __setup("con", console_chan_setup);
198 __channel_help(console_chan_setup, "con");