diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/vt/vt.c | 93 |
1 files changed, 70 insertions, 23 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 8fd89687d068..c076af0b300b 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -2987,7 +2987,7 @@ int __init vty_init(const struct file_operations *console_fops) static struct class *vtconsole_class; -static int bind_con_driver(const struct consw *csw, int first, int last, +static int do_bind_con_driver(const struct consw *csw, int first, int last, int deflt) { struct module *owner = csw->owner; @@ -2998,7 +2998,7 @@ static int bind_con_driver(const struct consw *csw, int first, int last, if (!try_module_get(owner)) return -ENODEV; - console_lock(); + WARN_CONSOLE_UNLOCKED(); /* check if driver is registered */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { @@ -3083,11 +3083,22 @@ static int bind_con_driver(const struct consw *csw, int first, int last, retval = 0; err: - console_unlock(); module_put(owner); return retval; }; + +static int bind_con_driver(const struct consw *csw, int first, int last, + int deflt) +{ + int ret; + + console_lock(); + ret = do_bind_con_driver(csw, first, last, deflt); + console_unlock(); + return ret; +} + #ifdef CONFIG_VT_HW_CONSOLE_BINDING static int con_is_graphics(const struct consw *csw, int first, int last) { @@ -3199,9 +3210,9 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) if (!con_is_bound(csw)) con_driver->flag &= ~CON_DRIVER_FLAG_INIT; - console_unlock(); /* ignore return value, binding should not fail */ - bind_con_driver(defcsw, first, last, deflt); + do_bind_con_driver(defcsw, first, last, deflt); + console_unlock(); err: module_put(owner); return retval; @@ -3492,28 +3503,18 @@ int con_debug_leave(void) } EXPORT_SYMBOL_GPL(con_debug_leave); -/** - * register_con_driver - register console driver to console layer - * @csw: console driver - * @first: the first console to take over, minimum value is 0 - * @last: the last console to take over, maximum value is MAX_NR_CONSOLES -1 - * - * DESCRIPTION: This function registers a console driver which can later - * bind to a range of consoles specified by @first and @last. It will - * also initialize the console driver by calling con_startup(). - */ -int register_con_driver(const struct consw *csw, int first, int last) +static int do_register_con_driver(const struct consw *csw, int first, int last) { struct module *owner = csw->owner; struct con_driver *con_driver; const char *desc; int i, retval = 0; + WARN_CONSOLE_UNLOCKED(); + if (!try_module_get(owner)) return -ENODEV; - console_lock(); - for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_driver = ®istered_con_driver[i]; @@ -3566,10 +3567,29 @@ int register_con_driver(const struct consw *csw, int first, int last) } err: - console_unlock(); module_put(owner); return retval; } + +/** + * register_con_driver - register console driver to console layer + * @csw: console driver + * @first: the first console to take over, minimum value is 0 + * @last: the last console to take over, maximum value is MAX_NR_CONSOLES -1 + * + * DESCRIPTION: This function registers a console driver which can later + * bind to a range of consoles specified by @first and @last. It will + * also initialize the console driver by calling con_startup(). + */ +int register_con_driver(const struct consw *csw, int first, int last) +{ + int retval; + + console_lock(); + retval = do_register_con_driver(csw, first, last); + console_unlock(); + return retval; +} EXPORT_SYMBOL(register_con_driver); /** @@ -3623,17 +3643,44 @@ EXPORT_SYMBOL(unregister_con_driver); * when a driver wants to take over some existing consoles * and become default driver for newly opened ones. * - * take_over_console is basically a register followed by unbind + * take_over_console is basically a register followed by unbind + */ +int do_take_over_console(const struct consw *csw, int first, int last, int deflt) +{ + int err; + + err = do_register_con_driver(csw, first, last); + /* + * If we get an busy error we still want to bind the console driver + * and return success, as we may have unbound the console driver + * but not unregistered it. + */ + if (err == -EBUSY) + err = 0; + if (!err) + do_bind_con_driver(csw, first, last, deflt); + + return err; +} +EXPORT_SYMBOL_GPL(do_take_over_console); + +/* + * If we support more console drivers, this function is used + * when a driver wants to take over some existing consoles + * and become default driver for newly opened ones. + * + * take_over_console is basically a register followed by unbind */ int take_over_console(const struct consw *csw, int first, int last, int deflt) { int err; err = register_con_driver(csw, first, last); - /* if we get an busy error we still want to bind the console driver + /* + * If we get an busy error we still want to bind the console driver * and return success, as we may have unbound the console driver - * but not unregistered it. - */ + * but not unregistered it. + */ if (err == -EBUSY) err = 0; if (!err) |