ssl.c

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/* 
 * Copyright (C) 2000, 2002 Jeff Dike ([email protected])
 * Licensed under the GPL
 */

#include <linux/fs.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/major.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/console.h>
#include <asm/termbits.h>
#include <asm/irq.h>
#include "ssl.h"
#include "chan.h"
#include <init.h>
#include <irq_user.h>
#include "mconsole_kern.h"

static const int ssl_version = 1;

#define NR_PORTS 64

static void ssl_announce(char *dev_name, int dev)
{
    printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
           dev_name);
}

/* Almost const, except that xterm_title may be changed in an initcall */
static struct chan_opts opts = {
    .announce   = ssl_announce,
    .xterm_title    = "Serial Line #%d",
    .raw        = 1,
};

static int ssl_config(char *str, char **error_out);
static int ssl_get_config(char *dev, char *str, int size, char **error_out);
static int ssl_remove(int n, char **error_out);


/* Const, except for .mc.list */
static struct line_driver driver = {
    .name           = "UML serial line",
    .device_name        = "ttyS",
    .major          = TTY_MAJOR,
    .minor_start        = 64,
    .type           = TTY_DRIVER_TYPE_SERIAL,
    .subtype        = 0,
    .read_irq       = SSL_IRQ,
    .read_irq_name      = "ssl",
    .write_irq      = SSL_WRITE_IRQ,
    .write_irq_name     = "ssl-write",
    .mc  = {
        .list       = LIST_HEAD_INIT(driver.mc.list),
        .name       = "ssl",
        .config     = ssl_config,
        .get_config     = ssl_get_config,
        .id     = line_id,
        .remove     = ssl_remove,
    },
};

/* The array is initialized by line_init, at initcall time.  The
 * elements are locked individually as needed.
 */
static char *conf[NR_PORTS];
static char *def_conf = CONFIG_SSL_CHAN;
static struct line serial_lines[NR_PORTS];

static int ssl_config(char *str, char **error_out)
{
    return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
               error_out);
}

static int ssl_get_config(char *dev, char *str, int size, char **error_out)
{
    return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
                   size, error_out);
}

static int ssl_remove(int n, char **error_out)
{
    return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
               error_out);
}

static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
{
    return line_install(driver, tty, &serial_lines[tty->index]);
}

static const struct tty_operations ssl_ops = {
    .open           = line_open,
    .close          = line_close,
    .write          = line_write,
    .put_char       = line_put_char,
    .write_room     = line_write_room,
    .chars_in_buffer    = line_chars_in_buffer,
    .flush_buffer       = line_flush_buffer,
    .flush_chars        = line_flush_chars,
    .set_termios        = line_set_termios,
    .throttle       = line_throttle,
    .unthrottle         = line_unthrottle,
    .install        = ssl_install,
    .cleanup        = line_cleanup,
    .hangup         = line_hangup,
};

/* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 * by being an initcall and exitcall, respectively.
 */
static int ssl_init_done = 0;

static void ssl_console_write(struct console *c, const char *string,
                  unsigned len)
{
    struct line *line = &serial_lines[c->index];
    unsigned long flags;

    spin_lock_irqsave(&line->lock, flags);
    console_write_chan(line->chan_out, string, len);
    spin_unlock_irqrestore(&line->lock, flags);
}

static struct tty_driver *ssl_console_device(struct console *c, int *index)
{
    *index = c->index;
    return driver.driver;
}

static int ssl_console_setup(struct console *co, char *options)
{
    struct line *line = &serial_lines[co->index];

    return console_open_chan(line, co);
}

/* No locking for register_console call - relies on single-threaded initcalls */
static struct console ssl_cons = {
    .name       = "ttyS",
    .write      = ssl_console_write,
    .device     = ssl_console_device,
    .setup      = ssl_console_setup,
    .flags      = CON_PRINTBUFFER|CON_ANYTIME,
    .index      = -1,
};

static int ssl_init(void)
{
    char *new_title;
    int err;
    int i;

    printk(KERN_INFO "Initializing software serial port version %d\n",
           ssl_version);

    err = register_lines(&driver, &ssl_ops, serial_lines,
                    ARRAY_SIZE(serial_lines));
    if (err)
        return err;

    new_title = add_xterm_umid(opts.xterm_title);
    if (new_title != NULL)
        opts.xterm_title = new_title;

    for (i = 0; i < NR_PORTS; i++) {
        char *error;
        char *s = conf[i];
        if (!s)
            s = def_conf;
        if (setup_one_line(serial_lines, i, s, &opts, &error))
            printk(KERN_ERR "setup_one_line failed for "
                   "device %d : %s\n", i, error);
    }

    ssl_init_done = 1;
    register_console(&ssl_cons);
    return 0;
}
late_initcall(ssl_init);

static void ssl_exit(void)
{
    if (!ssl_init_done)
        return;
    close_lines(serial_lines, ARRAY_SIZE(serial_lines));
}
__uml_exitcall(ssl_exit);

static int ssl_chan_setup(char *str)
{
    line_setup(conf, NR_PORTS, &def_conf, str, "serial line");
    return 1;
}

__setup("ssl", ssl_chan_setup);
__channel_help(ssl_chan_setup, "ssl");