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 #include "2_5compat.h"
  32
  33 #define MAX_TTYS (16)
  34
  35 /* ----------------------------------------------------------------------------- */
  36
  37 /* Referenced only by tty_driver below - presumably it's locked correctly
  38  * by the tty driver.
  39  */
  40
  41 static struct tty_driver *console_driver;
  42
  43 void stdio_announce(char *dev_name, int dev)
  44 {
  45         printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
  46                dev_name);
  47 }
  48
  49 static struct chan_opts opts = {
  50         .announce       = stdio_announce,
  51         .xterm_title    = "Virtual Console #%d",
  52         .raw            = 1,
  53         .tramp_stack    = 0,
  54         .in_kernel      = 1,
  55 };
  56
  57 static int con_config(char *str);
  58 static int con_get_config(char *dev, char *str, int size, char **error_out);
  59 static int con_remove(char *str);
  60
  61 static struct line_driver driver = {
  62         .name                   = "UML console",
  63         .device_name            = "tty",
  64         .devfs_name             = "vc/",
  65         .major                  = TTY_MAJOR,
  66         .minor_start            = 0,
  67         .type                   = TTY_DRIVER_TYPE_CONSOLE,
  68         .subtype                = SYSTEM_TYPE_CONSOLE,
  69         .read_irq               = CONSOLE_IRQ,
  70         .read_irq_name          = "console",
  71         .write_irq              = CONSOLE_WRITE_IRQ,
  72         .write_irq_name         = "console-write",
  73         .symlink_from           = "ttys",
  74         .symlink_to             = "vc",
  75         .mc  = {
  76                 .name           = "con",
  77                 .config         = con_config,
  78                 .get_config     = con_get_config,
  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(char *str)
 104 {
 105         return(line_remove(vts, sizeof(vts)/sizeof(vts[0]), str));
 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         .write_room             = line_write_room,
 120         .chars_in_buffer        = line_chars_in_buffer,
 121         .set_termios            = line_set_termios,
 122         .ioctl                  = line_ioctl,
 123 };
 124
 125 static void uml_console_write(struct console *console, const char *string,
 126                           unsigned len)
 127 {
 128         struct line *line = &vts[console->index];
 129
 130         down(&line->sem);
 131         console_write_chan(&line->chan_list, string, len);
 132         up(&line->sem);
 133 }
 134
 135 static struct tty_driver *uml_console_device(struct console *c, int *index)
 136 {
 137         *index = c->index;
 138         return console_driver;
 139 }
 140
 141 static int uml_console_setup(struct console *co, char *options)
 142 {
 143         struct line *line = &vts[co->index];
 144
 145         return console_open_chan(line,co,&opts);
 146 }
 147
 148 static struct console stdiocons = {
 149         .name           = "tty",
 150         .write          = uml_console_write,
 151         .device         = uml_console_device,
 152         .setup          = uml_console_setup,
 153         .flags          = CON_PRINTBUFFER,
 154         .index          = -1,
 155         .data           = &vts,
 156 };
 157
 158 int stdio_init(void)
 159 {
 160         char *new_title;
 161
 162         console_driver = line_register_devfs(&console_lines, &driver,
 163                                              &console_ops, vts,
 164                                              ARRAY_SIZE(vts));
 165         if (NULL == console_driver)
 166                 return -1;
 167         printk(KERN_INFO "Initialized stdio console driver\n");
 168
 169         lines_init(vts, sizeof(vts)/sizeof(vts[0]));
 170
 171         new_title = add_xterm_umid(opts.xterm_title);
 172         if(new_title != NULL)
 173                 opts.xterm_title = new_title;
 174
 175         con_init_done = 1;
 176         register_console(&stdiocons);
 177         return(0);
 178 }
 179 late_initcall(stdio_init);
 180
 181 static void console_exit(void)
 182 {
 183         if (!con_init_done)
 184                 return;
 185         close_lines(vts, sizeof(vts)/sizeof(vts[0]));
 186 }
 187 __uml_exitcall(console_exit);
 188
 189 static int console_chan_setup(char *str)
 190 {
 191         return(line_setup(vts, sizeof(vts)/sizeof(vts[0]), str, 1));
 192 }
 193 __setup("con", console_chan_setup);
 194 __channel_help(console_chan_setup, "con");
 195
 196 /*
 197  * Overrides for Emacs so that we follow Linus's tabbing style.
 198  * Emacs will notice this stuff at the end of the file and automatically
 199  * adjust the settings for this buffer only.  This must remain at the end
 200  * of the file.
 201  * ---------------------------------------------------------------------------
 202  * Local variables:
 203  * c-file-style: "linux"
 204  * End:
 205  */