1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
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
stdio_announce(char * dev_name,int dev)30 static 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 */
37 static struct chan_opts opts = {
38 .announce = stdio_announce,
39 .xterm_title = "Virtual Console #%d",
40 .raw = 1,
41 };
42
43 static int con_config(char *str, char **error_out);
44 static int con_get_config(char *dev, char *str, int size, char **error_out);
45 static int con_remove(int n, char **con_remove);
46
47
48 /* Const, except for .mc.list */
49 static 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_name = "console",
57 .write_irq_name = "console-write",
58 .mc = {
59 .list = LIST_HEAD_INIT(driver.mc.list),
60 .name = "con",
61 .config = con_config,
62 .get_config = con_get_config,
63 .id = line_id,
64 .remove = con_remove,
65 },
66 };
67
68 /* The array is initialized by line_init, at initcall time. The
69 * elements are locked individually as needed.
70 */
71 static char *vt_conf[MAX_TTYS];
72 static char *def_conf;
73 static struct line vts[MAX_TTYS];
74
con_config(char * str,char ** error_out)75 static int con_config(char *str, char **error_out)
76 {
77 return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out);
78 }
79
con_get_config(char * dev,char * str,int size,char ** error_out)80 static int con_get_config(char *dev, char *str, int size, char **error_out)
81 {
82 return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
83 }
84
con_remove(int n,char ** error_out)85 static int con_remove(int n, char **error_out)
86 {
87 return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
88 }
89
90 /* Set in an initcall, checked in an exitcall */
91 static int con_init_done;
92
con_install(struct tty_driver * driver,struct tty_struct * tty)93 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
94 {
95 return line_install(driver, tty, &vts[tty->index]);
96 }
97
98 static const struct tty_operations console_ops = {
99 .open = line_open,
100 .install = con_install,
101 .close = line_close,
102 .write = line_write,
103 .write_room = line_write_room,
104 .chars_in_buffer = line_chars_in_buffer,
105 .flush_buffer = line_flush_buffer,
106 .flush_chars = line_flush_chars,
107 .throttle = line_throttle,
108 .unthrottle = line_unthrottle,
109 .hangup = line_hangup,
110 };
111
uml_console_write(struct console * console,const char * string,unsigned len)112 static void uml_console_write(struct console *console, const char *string,
113 unsigned len)
114 {
115 struct line *line = &vts[console->index];
116 unsigned long flags;
117
118 spin_lock_irqsave(&line->lock, flags);
119 console_write_chan(line->chan_out, string, len);
120 spin_unlock_irqrestore(&line->lock, flags);
121 }
122
uml_console_device(struct console * c,int * index)123 static struct tty_driver *uml_console_device(struct console *c, int *index)
124 {
125 *index = c->index;
126 return driver.driver;
127 }
128
uml_console_setup(struct console * co,char * options)129 static int uml_console_setup(struct console *co, char *options)
130 {
131 struct line *line = &vts[co->index];
132
133 return console_open_chan(line, co);
134 }
135
136 /* No locking for register_console call - relies on single-threaded initcalls */
137 static struct console stdiocons = {
138 .name = "tty",
139 .write = uml_console_write,
140 .device = uml_console_device,
141 .setup = uml_console_setup,
142 .flags = CON_PRINTBUFFER|CON_ANYTIME,
143 .index = -1,
144 };
145
stdio_init(void)146 static int stdio_init(void)
147 {
148 char *new_title;
149 int err;
150 int i;
151
152 err = register_lines(&driver, &console_ops, vts,
153 ARRAY_SIZE(vts));
154 if (err)
155 return err;
156
157 printk(KERN_INFO "Initialized stdio console driver\n");
158
159 new_title = add_xterm_umid(opts.xterm_title);
160 if(new_title != NULL)
161 opts.xterm_title = new_title;
162
163 for (i = 0; i < MAX_TTYS; i++) {
164 char *error;
165 char *s = vt_conf[i];
166 if (!s)
167 s = def_conf;
168 if (!s)
169 s = i ? CONFIG_CON_CHAN : CONFIG_CON_ZERO_CHAN;
170 if (setup_one_line(vts, i, s, &opts, &error))
171 printk(KERN_ERR "setup_one_line failed for "
172 "device %d : %s\n", i, error);
173 }
174
175 con_init_done = 1;
176 register_console(&stdiocons);
177 return 0;
178 }
179 late_initcall(stdio_init);
180
console_exit(void)181 static void console_exit(void)
182 {
183 if (!con_init_done)
184 return;
185 close_lines(vts, ARRAY_SIZE(vts));
186 }
187 __uml_exitcall(console_exit);
188
console_chan_setup(char * str)189 static int console_chan_setup(char *str)
190 {
191 if (!strncmp(str, "sole=", 5)) /* console= option specifies tty */
192 return 0;
193
194 line_setup(vt_conf, MAX_TTYS, &def_conf, str, "console");
195 return 1;
196 }
197 __setup("con", console_chan_setup);
198 __channel_help(console_chan_setup, "con");
199