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/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
  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               = CONSOLE_IRQ,
  57         .read_irq_name          = "console",
  58         .write_irq              = CONSOLE_WRITE_IRQ,
  59         .write_irq_name         = "console-write",
  60         .mc  = {
  61                 .list           = LIST_HEAD_INIT(driver.mc.list),
  62                 .name           = "con",
  63                 .config         = con_config,
  64                 .get_config     = con_get_config,
  65                 .id             = line_id,
  66                 .remove         = con_remove,
  67         },
  68 };
  69
  70 /* The array is initialized by line_init, at initcall time.  The
  71  * elements are locked individually as needed.
  72  */
  73 static char *vt_conf[MAX_TTYS];
  74 static char *def_conf;
  75 static struct line vts[MAX_TTYS];
  76
  77 static int con_config(char *str, char **error_out)
  78 {
  79         return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out);
  80 }
  81
  82 static int con_get_config(char *dev, char *str, int size, char **error_out)
  83 {
  84         return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
  85 }
  86
  87 static int con_remove(int n, char **error_out)
  88 {
  89         return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
  90 }
  91
  92 static int con_open(struct tty_struct *tty, struct file *filp)
  93 {
  94         int err = line_open(vts, tty);
  95         if (err)
  96                 printk(KERN_ERR "Failed to open console %d, err = %d\n",
  97                        tty->index, err);
  98
  99         return err;
 100 }
 101
 102 /* Set in an initcall, checked in an exitcall */
 103 static int con_init_done = 0;
 104
 105 static const struct tty_operations console_ops = {
 106         .open                   = con_open,
 107         .close                  = line_close,
 108         .write                  = line_write,
 109         .put_char               = line_put_char,
 110         .write_room             = line_write_room,
 111         .chars_in_buffer        = line_chars_in_buffer,
 112         .flush_buffer           = line_flush_buffer,
 113         .flush_chars            = line_flush_chars,
 114         .set_termios            = line_set_termios,
 115         .ioctl                  = line_ioctl,
 116         .throttle               = line_throttle,
 117         .unthrottle             = line_unthrottle,
 118 };
 119
 120 static void uml_console_write(struct console *console, const char *string,
 121                               unsigned len)
 122 {
 123         struct line *line = &vts[console->index];
 124         unsigned long flags;
 125
 126         spin_lock_irqsave(&line->lock, flags);
 127         console_write_chan(line->chan_out, string, len);
 128         spin_unlock_irqrestore(&line->lock, flags);
 129 }
 130
 131 static struct tty_driver *uml_console_device(struct console *c, int *index)
 132 {
 133         *index = c->index;
 134         return driver.driver;
 135 }
 136
 137 static int uml_console_setup(struct console *co, char *options)
 138 {
 139         struct line *line = &vts[co->index];
 140
 141         return console_open_chan(line, co);
 142 }
 143
 144 /* No locking for register_console call - relies on single-threaded initcalls */
 145 static struct console stdiocons = {
 146         .name           = "tty",
 147         .write          = uml_console_write,
 148         .device         = uml_console_device,
 149         .setup          = uml_console_setup,
 150         .flags          = CON_PRINTBUFFER|CON_ANYTIME,
 151         .index          = -1,
 152 };
 153
 154 static int stdio_init(void)
 155 {
 156         char *new_title;
 157         int err;
 158         int i;
 159
 160         err = register_lines(&driver, &console_ops, vts,
 161                                         ARRAY_SIZE(vts));
 162         if (err)
 163                 return err;
 164
 165         printk(KERN_INFO "Initialized stdio console driver\n");
 166
 167         new_title = add_xterm_umid(opts.xterm_title);
 168         if(new_title != NULL)
 169                 opts.xterm_title = new_title;
 170
 171         for (i = 0; i < MAX_TTYS; i++) {
 172                 char *error;
 173                 char *s = vt_conf[i];
 174                 if (!s)
 175                         s = def_conf;
 176                 if (!s)
 177                         s = i ? CONFIG_CON_CHAN : CONFIG_CON_ZERO_CHAN;
 178                 if (setup_one_line(vts, i, s, &opts, &error))
 179                         printk(KERN_ERR "setup_one_line failed for "
 180                                "device %d : %s\n", i, error);
 181         }
 182
 183         con_init_done = 1;
 184         register_console(&stdiocons);
 185         return 0;
 186 }
 187 late_initcall(stdio_init);
 188
 189 static void console_exit(void)
 190 {
 191         if (!con_init_done)
 192                 return;
 193         close_lines(vts, ARRAY_SIZE(vts));
 194 }
 195 __uml_exitcall(console_exit);
 196
 197 static int console_chan_setup(char *str)
 198 {
 199         line_setup(vt_conf, MAX_TTYS, &def_conf, str, "console");
 200         return 1;
 201 }
 202 __setup("con", console_chan_setup);
 203 __channel_help(console_chan_setup, "con");