stdio_console.c revision edea138584d7586a3b93b6d5ab5ec021d18e11e9
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 "line.h" 24#include "chan_kern.h" 25#include "irq_user.h" 26#include "mconsole_kern.h" 27#include "init.h" 28 29#define MAX_TTYS (16) 30 31/* Referenced only by tty_driver below - presumably it's locked correctly 32 * by the tty driver. 33 */ 34 35static struct tty_driver *console_driver; 36 37void stdio_announce(char *dev_name, int dev) 38{ 39 printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev, 40 dev_name); 41} 42 43/* Almost const, except that xterm_title may be changed in an initcall */ 44static struct chan_opts opts = { 45 .announce = stdio_announce, 46 .xterm_title = "Virtual Console #%d", 47 .raw = 1, 48}; 49 50static int con_config(char *str, char **error_out); 51static int con_get_config(char *dev, char *str, int size, char **error_out); 52static int con_remove(int n, char **con_remove); 53 54 55/* Const, except for .mc.list */ 56static struct line_driver driver = { 57 .name = "UML console", 58 .device_name = "tty", 59 .major = TTY_MAJOR, 60 .minor_start = 0, 61 .type = TTY_DRIVER_TYPE_CONSOLE, 62 .subtype = SYSTEM_TYPE_CONSOLE, 63 .read_irq = CONSOLE_IRQ, 64 .read_irq_name = "console", 65 .write_irq = CONSOLE_WRITE_IRQ, 66 .write_irq_name = "console-write", 67 .mc = { 68 .list = LIST_HEAD_INIT(driver.mc.list), 69 .name = "con", 70 .config = con_config, 71 .get_config = con_get_config, 72 .id = line_id, 73 .remove = con_remove, 74 }, 75}; 76 77/* The array is initialized by line_init, at initcall time. The 78 * elements are locked individually as needed. 79 */ 80static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver), 81 [ 1 ... MAX_TTYS - 1 ] = 82 LINE_INIT(CONFIG_CON_CHAN, &driver) }; 83 84static int con_config(char *str, char **error_out) 85{ 86 return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out); 87} 88 89static int con_get_config(char *dev, char *str, int size, char **error_out) 90{ 91 return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out); 92} 93 94static int con_remove(int n, char **error_out) 95{ 96 return line_remove(vts, ARRAY_SIZE(vts), n, error_out); 97} 98 99static int con_open(struct tty_struct *tty, struct file *filp) 100{ 101 int err = line_open(vts, tty); 102 if (err) 103 printk(KERN_ERR "Failed to open console %d, err = %d\n", 104 tty->index, err); 105 106 return err; 107} 108 109/* Set in an initcall, checked in an exitcall */ 110static int con_init_done = 0; 111 112static const struct tty_operations console_ops = { 113 .open = con_open, 114 .close = line_close, 115 .write = line_write, 116 .put_char = line_put_char, 117 .write_room = line_write_room, 118 .chars_in_buffer = line_chars_in_buffer, 119 .flush_buffer = line_flush_buffer, 120 .flush_chars = line_flush_chars, 121 .set_termios = line_set_termios, 122 .ioctl = line_ioctl, 123 .throttle = line_throttle, 124 .unthrottle = line_unthrottle, 125}; 126 127static void uml_console_write(struct console *console, const char *string, 128 unsigned len) 129{ 130 struct line *line = &vts[console->index]; 131 unsigned long flags; 132 133 spin_lock_irqsave(&line->lock, flags); 134 console_write_chan(&line->chan_list, string, len); 135 spin_unlock_irqrestore(&line->lock, flags); 136} 137 138static struct tty_driver *uml_console_device(struct console *c, int *index) 139{ 140 *index = c->index; 141 return console_driver; 142} 143 144static int uml_console_setup(struct console *co, char *options) 145{ 146 struct line *line = &vts[co->index]; 147 148 return console_open_chan(line, co); 149} 150 151/* No locking for register_console call - relies on single-threaded initcalls */ 152static 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|CON_ANYTIME, 158 .index = -1, 159}; 160 161int stdio_init(void) 162{ 163 char *new_title; 164 165 console_driver = register_lines(&driver, &console_ops, vts, 166 ARRAY_SIZE(vts)); 167 if (console_driver == NULL) 168 return -1; 169 printk(KERN_INFO "Initialized stdio console driver\n"); 170 171 new_title = add_xterm_umid(opts.xterm_title); 172 if(new_title != NULL) 173 opts.xterm_title = new_title; 174 175 lines_init(vts, ARRAY_SIZE(vts), &opts); 176 177 con_init_done = 1; 178 register_console(&stdiocons); 179 return 0; 180} 181late_initcall(stdio_init); 182 183static void console_exit(void) 184{ 185 if (!con_init_done) 186 return; 187 close_lines(vts, ARRAY_SIZE(vts)); 188} 189__uml_exitcall(console_exit); 190 191static int console_chan_setup(char *str) 192{ 193 char *error; 194 int ret; 195 196 ret = line_setup(vts, ARRAY_SIZE(vts), str, &error); 197 if(ret < 0) 198 printk(KERN_ERR "Failed to set up console with " 199 "configuration string \"%s\" : %s\n", str, error); 200 201 return 1; 202} 203__setup("con", console_chan_setup); 204__channel_help(console_chan_setup, "con"); 205