From 21aca2fa00259f781d228496631b61dbb4274e90 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 8 Aug 2012 22:26:41 +0200 Subject: [PATCH] TTY: pty, switch to tty_alloc_driver Switch to the new driver allocation interface, as this is one of the special call-sites. Here, we need TTY_DRIVER_DYNAMIC_ALLOC to not allocate tty_driver->ports, cdevs and potentially other structures because we reserve too many lines in pty. Instead, it provides the tty_port<->tty_struct link in tty->ops->install already. Signed-off-by: Jiri Slaby Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/pty.c | 31 ++++++++++++++++++++----------- include/linux/tty_driver.h | 4 ++++ 2 files changed, 24 insertions(+), 11 deletions(-) diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index d9ea9e2c9ec5..f5a27c66ff60 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -444,11 +444,17 @@ static void __init legacy_pty_init(void) if (legacy_count <= 0) return; - pty_driver = alloc_tty_driver(legacy_count); + pty_driver = tty_alloc_driver(legacy_count, + TTY_DRIVER_RESET_TERMIOS | + TTY_DRIVER_REAL_RAW | + TTY_DRIVER_DYNAMIC_ALLOC); if (!pty_driver) panic("Couldn't allocate pty driver"); - pty_slave_driver = alloc_tty_driver(legacy_count); + pty_slave_driver = tty_alloc_driver(legacy_count, + TTY_DRIVER_RESET_TERMIOS | + TTY_DRIVER_REAL_RAW | + TTY_DRIVER_DYNAMIC_ALLOC); if (!pty_slave_driver) panic("Couldn't allocate pty slave driver"); @@ -465,7 +471,6 @@ static void __init legacy_pty_init(void) pty_driver->init_termios.c_lflag = 0; pty_driver->init_termios.c_ispeed = 38400; 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, &master_pty_ops_bsd); @@ -479,8 +484,6 @@ static void __init legacy_pty_init(void) pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; pty_slave_driver->init_termios.c_ispeed = 38400; pty_slave_driver->init_termios.c_ospeed = 38400; - pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS | - TTY_DRIVER_REAL_RAW; pty_slave_driver->other = pty_driver; tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd); @@ -673,10 +676,20 @@ static struct file_operations ptmx_fops; static void __init unix98_pty_init(void) { - ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); + ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, + TTY_DRIVER_RESET_TERMIOS | + TTY_DRIVER_REAL_RAW | + TTY_DRIVER_DYNAMIC_DEV | + TTY_DRIVER_DEVPTS_MEM | + TTY_DRIVER_DYNAMIC_ALLOC); if (!ptm_driver) panic("Couldn't allocate Unix98 ptm driver"); - pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX); + pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX, + TTY_DRIVER_RESET_TERMIOS | + TTY_DRIVER_REAL_RAW | + TTY_DRIVER_DYNAMIC_DEV | + TTY_DRIVER_DEVPTS_MEM | + TTY_DRIVER_DYNAMIC_ALLOC); if (!pts_driver) panic("Couldn't allocate Unix98 pts driver"); @@ -693,8 +706,6 @@ static void __init unix98_pty_init(void) ptm_driver->init_termios.c_lflag = 0; ptm_driver->init_termios.c_ispeed = 38400; ptm_driver->init_termios.c_ospeed = 38400; - ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | - TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; ptm_driver->other = pts_driver; tty_set_operations(ptm_driver, &ptm_unix98_ops); @@ -708,8 +719,6 @@ static void __init unix98_pty_init(void) pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD; pts_driver->init_termios.c_ispeed = 38400; pts_driver->init_termios.c_ospeed = 38400; - pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | - TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM; pts_driver->other = ptm_driver; tty_set_operations(pts_driver, &pty_unix98_ops); diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h index 3adc362f0bd2..1a85f003d646 100644 --- a/include/linux/tty_driver.h +++ b/include/linux/tty_driver.h @@ -391,6 +391,9 @@ static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d) * the requested timeout to the caller instead of using a simple * on/off interface. * + * TTY_DRIVER_DYNAMIC_ALLOC -- do not allocate structures which are + * needed per line for this driver as it would waste memory. + * The driver will take care. */ #define TTY_DRIVER_INSTALLED 0x0001 #define TTY_DRIVER_RESET_TERMIOS 0x0002 @@ -398,6 +401,7 @@ static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d) #define TTY_DRIVER_DYNAMIC_DEV 0x0008 #define TTY_DRIVER_DEVPTS_MEM 0x0010 #define TTY_DRIVER_HARDWARE_BREAK 0x0020 +#define TTY_DRIVER_DYNAMIC_ALLOC 0x0040 /* tty driver types */ #define TTY_DRIVER_TYPE_SYSTEM 0x0001 -- 2.20.1