diff options
Diffstat (limited to 'drivers/tty/vt/vt.c')
| -rw-r--r-- | drivers/tty/vt/vt.c | 134 |
1 files changed, 97 insertions, 37 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index b3915b7..e41288a 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -3016,7 +3016,7 @@ 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; @@ -3027,7 +3027,7 @@ 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++) { @@ -3112,11 +3112,22 @@ 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) { @@ -3153,6 +3164,18 @@ static int con_is_graphics(const struct consw *csw, int first, int last) */ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) { + int retval; + + console_lock(); + retval = do_unbind_con_driver(csw, first, last, deflt); + console_unlock(); + return retval; +} +EXPORT_SYMBOL(unbind_con_driver); + +/* unlocked version of unbind_con_driver() */ +int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt) +{ struct module *owner = csw->owner; const struct consw *defcsw = NULL; struct con_driver *con_driver = NULL, *con_back = NULL; @@ -3161,7 +3184,7 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) if (!try_module_get(owner)) return -ENODEV; - console_lock(); + WARN_CONSOLE_UNLOCKED(); /* check if driver is registered and if it is unbindable */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { @@ -3174,10 +3197,8 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) } } - if (retval) { - console_unlock(); + if (retval) goto err; - } retval = -ENODEV; @@ -3193,15 +3214,11 @@ int unbind_con_driver(const struct consw *csw, int first, int last, int deflt) } } - if (retval) { - console_unlock(); + if (retval) goto err; - } - if (!con_is_bound(csw)) { - console_unlock(); + if (!con_is_bound(csw)) goto err; - } first = max(first, con_driver->first); last = min(last, con_driver->last); @@ -3228,15 +3245,14 @@ 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); err: module_put(owner); return retval; } -EXPORT_SYMBOL(unbind_con_driver); +EXPORT_SYMBOL_GPL(do_unbind_con_driver); static int vt_bind(struct con_driver *con) { @@ -3508,28 +3524,18 @@ 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]; @@ -3582,10 +3588,29 @@ 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); /** @@ -3601,9 +3626,18 @@ EXPORT_SYMBOL(register_con_driver); */ int unregister_con_driver(const struct consw *csw) { - int i, retval = -ENODEV; + int retval; console_lock(); + retval = do_unregister_con_driver(csw); + console_unlock(); + return retval; +} +EXPORT_SYMBOL(unregister_con_driver); + +int do_unregister_con_driver(const struct consw *csw) +{ + int i, retval = -ENODEV; /* cannot unregister a bound driver */ if (con_is_bound(csw)) @@ -3629,27 +3663,53 @@ int unregister_con_driver(const struct consw *csw) } } err: - console_unlock(); return retval; } -EXPORT_SYMBOL(unregister_con_driver); +EXPORT_SYMBOL_GPL(do_unregister_con_driver); /* * 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 + * 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) |