From 342a597146e8639f7c8d49f056340c2e5536dda6 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 30 Sep 2009 07:49:40 -0700 Subject: [PATCH] pty: reconnect the BSD TIOCSPTLCK handling to legacy ptys David Howells noticed (due to the compiler warning about an unused 'pty_ops_bsd' variable) that we haven't actually been using the code that implements TIOCSPTLCK for legacy pty handling. It's been that way since 2.6.26, commit 3e8e88ca053150efdbecb45d8f481cf560ec808d to be exact ("pty: prepare for tty->ops changes"). DavidH initially submitted a patch just removing the dead code entirely, and since nobody has apparently ever complained, I'm not entirely sure that wouldn't be the right thing to do. But since the whole and only point of the legacy pty code is to be compatible with legacy distros that don't use the new unix98 pty model, let's just wire it up again. And clean it up a bit while we're at it. Acked-by: David Howells Cc: Alan Cox Signed-off-by: Linus Torvalds --- drivers/char/pty.c | 47 +++++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 21 deletions(-) diff --git a/drivers/char/pty.c b/drivers/char/pty.c index 53761cefa915..e066c4fdf81b 100644 --- a/drivers/char/pty.c +++ b/drivers/char/pty.c @@ -261,6 +261,9 @@ done: return 0; } +/* Traditional BSD devices */ +#ifdef CONFIG_LEGACY_PTYS + static int pty_install(struct tty_driver *driver, struct tty_struct *tty) { struct tty_struct *o_tty; @@ -310,24 +313,6 @@ free_mem_out: return -ENOMEM; } - -static const struct tty_operations pty_ops = { - .install = pty_install, - .open = pty_open, - .close = pty_close, - .write = pty_write, - .write_room = pty_write_room, - .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, - .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, - .resize = pty_resize -}; - -/* Traditional BSD devices */ -#ifdef CONFIG_LEGACY_PTYS -static struct tty_driver *pty_driver, *pty_slave_driver; - static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { @@ -341,7 +326,12 @@ static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file, static int legacy_count = CONFIG_LEGACY_PTY_COUNT; module_param(legacy_count, int, 0); -static const struct tty_operations pty_ops_bsd = { +/* + * The master side of a pty can do TIOCSPTLCK and thus + * has pty_bsd_ioctl. + */ +static const struct tty_operations master_pty_ops_bsd = { + .install = pty_install, .open = pty_open, .close = pty_close, .write = pty_write, @@ -354,8 +344,23 @@ static const struct tty_operations pty_ops_bsd = { .resize = pty_resize }; +static const struct tty_operations slave_pty_ops_bsd = { + .install = pty_install, + .open = pty_open, + .close = pty_close, + .write = pty_write, + .write_room = pty_write_room, + .flush_buffer = pty_flush_buffer, + .chars_in_buffer = pty_chars_in_buffer, + .unthrottle = pty_unthrottle, + .set_termios = pty_set_termios, + .resize = pty_resize +}; + static void __init legacy_pty_init(void) { + struct tty_driver *pty_driver, *pty_slave_driver; + if (legacy_count <= 0) return; @@ -383,7 +388,7 @@ static void __init legacy_pty_init(void) pty_driver->init_termios.c_ospeed = 38400; pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW; pty_driver->other = pty_slave_driver; - tty_set_operations(pty_driver, &pty_ops); + tty_set_operations(pty_driver, &master_pty_ops_bsd); pty_slave_driver->owner = THIS_MODULE; pty_slave_driver->driver_name = "pty_slave"; @@ -399,7 +404,7 @@ static void __init legacy_pty_init(void) pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW; pty_slave_driver->other = pty_driver; - tty_set_operations(pty_slave_driver, &pty_ops); + tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); if (tty_register_driver(pty_driver)) panic("Couldn't register pty driver"); -- 2.30.2