arch/um/drivers/ssl.c

   1 /*
   2  * Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/fs.h"
   7 #include "linux/tty.h"
   8 #include "linux/tty_driver.h"
   9 #include "linux/major.h"
  10 #include "linux/mm.h"
  11 #include "linux/init.h"
  12 #include "linux/console.h"
  13 #include "asm/termbits.h"
  14 #include "asm/irq.h"
  15 #include "line.h"
  16 #include "ssl.h"
  17 #include "chan_kern.h"
  18 #include "kern_util.h"
  19 #include "kern.h"
  20 #include "init.h"
  21 #include "irq_user.h"
  22 #include "mconsole_kern.h"
  23
  24 static const int ssl_version = 1;
  25
  26 /* Referenced only by tty_driver below - presumably it's locked correctly
  27  * by the tty driver.
  28  */
  29
  30 static struct tty_driver *ssl_driver;
  31
  32 #define NR_PORTS 64
  33
  34 static void ssl_announce(char *dev_name, int dev)
  35 {
  36         printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
  37                dev_name);
  38 }
  39
  40 /* Almost const, except that xterm_title may be changed in an initcall */
  41 static struct chan_opts opts = {
  42         .announce       = ssl_announce,
  43         .xterm_title    = "Serial Line #%d",
  44         .raw            = 1,
  45 };
  46
  47 static int ssl_config(char *str, char **error_out);
  48 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
  49 static int ssl_remove(int n, char **error_out);
  50
  51
  52 /* Const, except for .mc.list */
  53 static struct line_driver driver = {
  54         .name                   = "UML serial line",
  55         .device_name            = "ttyS",
  56         .major                  = TTY_MAJOR,
  57         .minor_start            = 64,
  58         .type                   = TTY_DRIVER_TYPE_SERIAL,
  59         .subtype                = 0,
  60         .read_irq               = SSL_IRQ,
  61         .read_irq_name          = "ssl",
  62         .write_irq              = SSL_WRITE_IRQ,
  63         .write_irq_name         = "ssl-write",
  64         .mc  = {
  65                 .list           = LIST_HEAD_INIT(driver.mc.list),
  66                 .name           = "ssl",
  67                 .config         = ssl_config,
  68                 .get_config     = ssl_get_config,
  69                 .id             = line_id,
  70                 .remove         = ssl_remove,
  71         },
  72 };
  73
  74 /* The array is initialized by line_init, at initcall time.  The
  75  * elements are locked individually as needed.
  76  */
  77 static struct line serial_lines[NR_PORTS] =
  78         { [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
  79
  80 static int ssl_config(char *str, char **error_out)
  81 {
  82         return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
  83                            error_out);
  84 }
  85
  86 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
  87 {
  88         return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
  89                                size, error_out);
  90 }
  91
  92 static int ssl_remove(int n, char **error_out)
  93 {
  94         return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
  95                            error_out);
  96 }
  97
  98 static int ssl_open(struct tty_struct *tty, struct file *filp)
  99 {
 100         int err = line_open(serial_lines, tty);
 101
 102         if (err)
 103                 printk(KERN_ERR "Failed to open serial line %d, err = %d\n",
 104                        tty->index, err);
 105
 106         return err;
 107 }
 108
 109 #if 0
 110 static void ssl_flush_buffer(struct tty_struct *tty)
 111 {
 112         return;
 113 }
 114
 115 static void ssl_stop(struct tty_struct *tty)
 116 {
 117         printk(KERN_ERR "Someone should implement ssl_stop\n");
 118 }
 119
 120 static void ssl_start(struct tty_struct *tty)
 121 {
 122         printk(KERN_ERR "Someone should implement ssl_start\n");
 123 }
 124
 125 void ssl_hangup(struct tty_struct *tty)
 126 {
 127 }
 128 #endif
 129
 130 static const struct tty_operations ssl_ops = {
 131         .open                   = ssl_open,
 132         .close                  = line_close,
 133         .write                  = line_write,
 134         .put_char               = line_put_char,
 135         .write_room             = line_write_room,
 136         .chars_in_buffer        = line_chars_in_buffer,
 137         .flush_buffer           = line_flush_buffer,
 138         .flush_chars            = line_flush_chars,
 139         .set_termios            = line_set_termios,
 140         .ioctl                  = line_ioctl,
 141         .throttle               = line_throttle,
 142         .unthrottle             = line_unthrottle,
 143 #if 0
 144         .stop                   = ssl_stop,
 145         .start                  = ssl_start,
 146         .hangup                 = ssl_hangup,
 147 #endif
 148 };
 149
 150 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 151  * by being an initcall and exitcall, respectively.
 152  */
 153 static int ssl_init_done = 0;
 154
 155 static void ssl_console_write(struct console *c, const char *string,
 156                               unsigned len)
 157 {
 158         struct line *line = &serial_lines[c->index];
 159         unsigned long flags;
 160
 161         spin_lock_irqsave(&line->lock, flags);
 162         console_write_chan(&line->chan_list, string, len);
 163         spin_unlock_irqrestore(&line->lock, flags);
 164 }
 165
 166 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 167 {
 168         *index = c->index;
 169         return ssl_driver;
 170 }
 171
 172 static int ssl_console_setup(struct console *co, char *options)
 173 {
 174         struct line *line = &serial_lines[co->index];
 175
 176         return console_open_chan(line, co);
 177 }
 178
 179 /* No locking for register_console call - relies on single-threaded initcalls */
 180 static struct console ssl_cons = {
 181         .name           = "ttyS",
 182         .write          = ssl_console_write,
 183         .device         = ssl_console_device,
 184         .setup          = ssl_console_setup,
 185         .flags          = CON_PRINTBUFFER|CON_ANYTIME,
 186         .index          = -1,
 187 };
 188
 189 static int ssl_init(void)
 190 {
 191         char *new_title;
 192
 193         printk(KERN_INFO "Initializing software serial port version %d\n",
 194                ssl_version);
 195         ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
 196                                     ARRAY_SIZE(serial_lines));
 197
 198         new_title = add_xterm_umid(opts.xterm_title);
 199         if (new_title != NULL)
 200                 opts.xterm_title = new_title;
 201
 202         lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
 203
 204         ssl_init_done = 1;
 205         register_console(&ssl_cons);
 206         return 0;
 207 }
 208 late_initcall(ssl_init);
 209
 210 static void ssl_exit(void)
 211 {
 212         if (!ssl_init_done)
 213                 return;
 214         close_lines(serial_lines, ARRAY_SIZE(serial_lines));
 215 }
 216 __uml_exitcall(ssl_exit);
 217
 218 static int ssl_chan_setup(char *str)
 219 {
 220         char *error;
 221         int ret;
 222
 223         ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error);
 224         if(ret < 0)
 225                 printk(KERN_ERR "Failed to set up serial line with "
 226                        "configuration string \"%s\" : %s\n", str, error);
 227
 228         return 1;
 229 }
 230
 231 __setup("ssl", ssl_chan_setup);
 232 __channel_help(ssl_chan_setup, "ssl");