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 (8)
  34
  35 /* Referenced only by tty_driver below - presumably it's locked correctly
  36  * by the tty driver.
  37  */
  38
  39 static struct tty_driver *console_driver;
  40
  41 static struct chan_ops init_console_ops = {
  42         .type           = "you shouldn't see this",
  43         .init           = NULL,
  44         .open           = NULL,
  45         .close          = NULL,
  46         .read           = NULL,
  47         .write          = NULL,
  48         .console_write  = generic_write,
  49         .window_size    = NULL,
  50         .free           = NULL,
  51         .winch          = 0,
  52 };
  53
  54 static struct chan init_console_chan = {
  55         .list           = { },
  56         .primary        = 1,
  57         .input          = 0,
  58         .output         = 1,
  59         .opened         = 1,
  60         .fd             = 1,
  61         .pri            = INIT_STATIC,
  62         .ops            = &init_console_ops,
  63         .data           = NULL
  64 };
  65
  66 void stdio_announce(char *dev_name, int dev)
  67 {
  68         printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
  69                dev_name);
  70 }
  71
  72 static struct chan_opts opts = {
  73         .announce       = stdio_announce,
  74         .xterm_title    = "Virtual Console #%d",
  75         .raw            = 1,
  76         .tramp_stack    = 0,
  77         .in_kernel      = 1,
  78 };
  79
  80 static int con_config(char *str);
  81 static int con_get_config(char *dev, char *str, int size, char **error_out);
  82 static int con_remove(char *str);
  83
  84 static struct line_driver driver = {
  85         .name                   = "UML console",
  86         .device_name            = "tty",
  87         .devfs_name             = "vc/",
  88         .major                  = TTY_MAJOR,
  89         .minor_start            = 0,
  90         .type                   = TTY_DRIVER_TYPE_CONSOLE,
  91         .subtype                = SYSTEM_TYPE_CONSOLE,
  92         .read_irq               = CONSOLE_IRQ,
  93         .read_irq_name          = "console",
  94         .write_irq              = CONSOLE_WRITE_IRQ,
  95         .write_irq_name         = "console-write",
  96         .symlink_from           = "ttys",
  97         .symlink_to             = "vc",
  98         .mc  = {
  99                 .name           = "con",
 100                 .config         = con_config,
 101                 .get_config     = con_get_config,
 102                 .remove         = con_remove,
 103         },
 104 };
 105
 106 static struct lines console_lines = LINES_INIT(MAX_TTYS);
 107
 108 /* The array is initialized by line_init, which is an initcall.  The
 109  * individual elements are protected by individual semaphores.
 110  */
 111 struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
 112                               [ 1 ... MAX_TTYS - 1 ] =
 113                               LINE_INIT(CONFIG_CON_CHAN, &driver) };
 114
 115 static int con_config(char *str)
 116 {
 117         return(line_config(vts, sizeof(vts)/sizeof(vts[0]), str));
 118 }
 119
 120 static int con_get_config(char *dev, char *str, int size, char **error_out)
 121 {
 122         return(line_get_config(dev, vts, sizeof(vts)/sizeof(vts[0]), str,
 123                                size, error_out));
 124 }
 125
 126 static int con_remove(char *str)
 127 {
 128         return(line_remove(vts, sizeof(vts)/sizeof(vts[0]), str));
 129 }
 130
 131 static int open_console(struct tty_struct *tty)
 132 {
 133         return(line_open(vts, tty, &opts));
 134 }
 135
 136 static int con_open(struct tty_struct *tty, struct file *filp)
 137 {
 138         return(open_console(tty));
 139 }
 140
 141 static void con_close(struct tty_struct *tty, struct file *filp)
 142 {
 143         line_close(vts, tty);
 144 }
 145
 146 static int con_write(struct tty_struct *tty, int from_user,
 147                      const unsigned char *buf, int count)
 148 {
 149          return(line_write(vts, tty, from_user, buf, count));
 150 }
 151
 152 static void set_termios(struct tty_struct *tty, struct termios * old)
 153 {
 154 }
 155
 156 static int chars_in_buffer(struct tty_struct *tty)
 157 {
 158         return(0);
 159 }
 160
 161 static int con_init_done = 0;
 162
 163 static struct tty_operations console_ops = {
 164         .open                   = con_open,
 165         .close                  = con_close,
 166         .write                  = con_write,
 167         .chars_in_buffer        = chars_in_buffer,
 168         .set_termios            = set_termios,
 169         .write_room             = line_write_room,
 170 };
 171
 172 int stdio_init(void)
 173 {
 174         char *new_title;
 175
 176         printk(KERN_INFO "Initializing stdio console driver\n");
 177
 178         console_driver = line_register_devfs(&console_lines, &driver,
 179                                              &console_ops, vts,
 180                                              sizeof(vts)/sizeof(vts[0]));
 181
 182         lines_init(vts, sizeof(vts)/sizeof(vts[0]));
 183
 184         new_title = add_xterm_umid(opts.xterm_title);
 185         if(new_title != NULL) opts.xterm_title = new_title;
 186
 187         open_console(NULL);
 188         con_init_done = 1;
 189         return(0);
 190 }
 191
 192 late_initcall(stdio_init);
 193
 194 static void uml_console_write(struct console *console, const char *string,
 195                           unsigned len)
 196 {
 197         struct line *line = &vts[console->index];
 198
 199         if(con_init_done)
 200                 down(&line->sem);
 201         console_write_chan(&line->chan_list, string, len);
 202         if(con_init_done)
 203                 up(&line->sem);
 204 }
 205
 206 static struct tty_driver *uml_console_device(struct console *c, int *index)
 207 {
 208         *index = c->index;
 209         return console_driver;
 210 }
 211
 212 static int uml_console_setup(struct console *co, char *options)
 213 {
 214         return(0);
 215 }
 216
 217 static struct console stdiocons = {
 218         name:           "tty",
 219         write:          uml_console_write,
 220         device:         uml_console_device,
 221         setup:          uml_console_setup,
 222         flags:          CON_PRINTBUFFER,
 223         index:          -1,
 224 };
 225
 226 static int __init stdio_console_init(void)
 227 {
 228         INIT_LIST_HEAD(&vts[0].chan_list);
 229         list_add(&init_console_chan.list, &vts[0].chan_list);
 230         register_console(&stdiocons);
 231         return(0);
 232 }
 233
 234 console_initcall(stdio_console_init);
 235
 236 static int console_chan_setup(char *str)
 237 {
 238         return(line_setup(vts, sizeof(vts)/sizeof(vts[0]), str, 1));
 239 }
 240
 241 __setup("con", console_chan_setup);
 242 __channel_help(console_chan_setup, "con");
 243
 244 static void console_exit(void)
 245 {
 246         if(!con_init_done) return;
 247         close_lines(vts, sizeof(vts)/sizeof(vts[0]));
 248 }
 249
 250 __uml_exitcall(console_exit);
 251
 252 /*
 253  * Overrides for Emacs so that we follow Linus's tabbing style.
 254  * Emacs will notice this stuff at the end of the file and automatically
 255  * adjust the settings for this buffer only.  This must remain at the end
 256  * of the file.
 257  * ---------------------------------------------------------------------------
 258  * Local variables:
 259  * c-file-style: "linux"
 260  * End:
 261  */