From 4ea3cd65e0d47c4d3fc0c86d2d93d97457dc86fb Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Fri, 18 Dec 2020 11:42:44 +0100 Subject: tty: rename tty_kopen() and add new function tty_kopen_shared() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce a new function tty_kopen_shared() that yields a struct tty_struct. The semantic difference to tty_kopen() is that the tty is expected to be used already. So rename tty_kopen() to tty_kopen_exclusive() for clearness, adapt the single user and put the common code in a new static helper function. tty_kopen_shared is to be used to implement an LED trigger for tty devices in one of the next patches. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20201218104246.591315-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman --- include/linux/tty.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux/tty.h') diff --git a/include/linux/tty.h b/include/linux/tty.h index c873f475f0a7..df707a5abfac 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -416,7 +416,8 @@ extern struct tty_struct *get_current_tty(void); /* tty_io.c */ extern int __init tty_init(void); extern const char *tty_name(const struct tty_struct *tty); -extern struct tty_struct *tty_kopen(dev_t device); +extern struct tty_struct *tty_kopen_exclusive(dev_t device); +extern struct tty_struct *tty_kopen_shared(dev_t device); extern void tty_kclose(struct tty_struct *tty); extern int tty_dev_name_to_number(const char *name, dev_t *number); extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout); @@ -441,7 +442,7 @@ static inline int __init tty_init(void) { return 0; } static inline const char *tty_name(const struct tty_struct *tty) { return "(none)"; } -static inline struct tty_struct *tty_kopen(dev_t device) +static inline struct tty_struct *tty_kopen_exclusive(dev_t device) { return ERR_PTR(-ENODEV); } static inline void tty_kclose(struct tty_struct *tty) { } -- cgit v1.3.1 From d20c219c7317843cec7f03eba15bfeae54f29654 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Fri, 18 Dec 2020 11:42:45 +0100 Subject: tty: new helper function tty_get_icount() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For a given struct tty_struct this yields the corresponding statistics about sent and received characters (and some more) which is needed to implement an LED trigger for tty devices. The new function is then used to simplify tty_tiocgicount(). Reviewed-by: Pavel Machek Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20201218104246.591315-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 29 +++++++++++++++++++++++++---- include/linux/tty.h | 2 ++ 2 files changed, 27 insertions(+), 4 deletions(-) (limited to 'include/linux/tty.h') diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 62ccd021102d..95ba028ef668 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2488,15 +2488,36 @@ static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd, return tty->ops->tiocmset(tty, set, clear); } +/** + * tty_get_icount - get tty statistics + * @tty: tty device + * @icount: output parameter + * + * Gets a copy of the tty's icount statistics. + * + * Locking: none (up to the driver) + */ +int tty_get_icount(struct tty_struct *tty, + struct serial_icounter_struct *icount) +{ + memset(icount, 0, sizeof(*icount)); + + if (tty->ops->get_icount) + return tty->ops->get_icount(tty, icount); + else + return -EINVAL; +} +EXPORT_SYMBOL_GPL(tty_get_icount); + static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) { - int retval = -EINVAL; struct serial_icounter_struct icount; - memset(&icount, 0, sizeof(icount)); - if (tty->ops->get_icount) - retval = tty->ops->get_icount(tty, &icount); + int retval; + + retval = tty_get_icount(tty, &icount); if (retval != 0) return retval; + if (copy_to_user(arg, &icount, sizeof(icount))) return -EFAULT; return 0; diff --git a/include/linux/tty.h b/include/linux/tty.h index df707a5abfac..12be8b16cdef 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -500,6 +500,8 @@ extern void tty_unthrottle(struct tty_struct *tty); extern int tty_throttle_safe(struct tty_struct *tty); extern int tty_unthrottle_safe(struct tty_struct *tty); extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); +extern int tty_get_icount(struct tty_struct *tty, + struct serial_icounter_struct *icount); extern int is_current_pgrp_orphaned(void); extern void tty_hangup(struct tty_struct *tty); extern void tty_vhangup(struct tty_struct *tty); -- cgit v1.3.1 From 0bc1bd092af3c7c0b025ece93c3a86916f89f3ca Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Tue, 5 Jan 2021 13:02:38 +0100 Subject: tty_port: drop last traces of low_latency The main purpose of tty_port::low_latency was removed in commit a9c3f68f3cd8 (tty: Fix low_latency BUG) back in 2014. It was left in place for drivers as an optional tune knob. But only one driver has been using it until the previous commit. So remove this misconcept completely, given there are no users. Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210105120239.28031-11-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman --- Documentation/networking/caif/caif.rst | 1 - drivers/char/pcmcia/synclink_cs.c | 2 -- drivers/net/caif/caif_serial.c | 3 +-- drivers/s390/char/con3215.c | 1 - drivers/s390/char/sclp_tty.c | 1 - drivers/s390/char/sclp_vt220.c | 1 - drivers/s390/char/tty3270.c | 2 -- drivers/tty/amiserial.c | 3 --- drivers/tty/hvc/hvcs.c | 2 +- drivers/tty/ipwireless/tty.c | 1 - drivers/tty/mxser.c | 1 - drivers/tty/serial/ifx6x60.c | 3 --- drivers/tty/serial/max3100.c | 3 --- drivers/tty/serial/serial_core.c | 3 --- drivers/tty/synclink_gt.c | 1 - include/linux/tty.h | 3 +-- 16 files changed, 3 insertions(+), 28 deletions(-) (limited to 'include/linux/tty.h') diff --git a/Documentation/networking/caif/caif.rst b/Documentation/networking/caif/caif.rst index a07213030ccf..81a14373d780 100644 --- a/Documentation/networking/caif/caif.rst +++ b/Documentation/networking/caif/caif.rst @@ -68,7 +68,6 @@ There are debugfs parameters provided for serial communication. * tty_status: Prints the bit-mask tty status information - 0x01 - tty->warned is on. - - 0x02 - tty->low_latency is on. - 0x04 - tty->packed is on. - 0x08 - tty->flow_stopped is on. - 0x10 - tty->hw_stopped is on. diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c index e342daa73d1b..2be8d9a8eec5 100644 --- a/drivers/char/pcmcia/synclink_cs.c +++ b/drivers/char/pcmcia/synclink_cs.c @@ -2494,8 +2494,6 @@ static int mgslpc_open(struct tty_struct *tty, struct file * filp) printk("%s(%d):mgslpc_open(%s), old ref count = %d\n", __FILE__, __LINE__, tty->driver->name, port->count); - port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0; - spin_lock_irqsave(&info->netlock, flags); if (info->netcount) { retval = -EBUSY; diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c index bcc14c5875bf..8215cd77301f 100644 --- a/drivers/net/caif/caif_serial.c +++ b/drivers/net/caif/caif_serial.c @@ -89,8 +89,7 @@ static inline void update_tty_status(struct ser_device *ser) ser->tty_status = ser->tty->stopped << 5 | ser->tty->flow_stopped << 3 | - ser->tty->packet << 2 | - ser->tty->port->low_latency << 1; + ser->tty->packet << 2; } static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty) { diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c index 1354c42d95aa..671efee612af 100644 --- a/drivers/s390/char/con3215.c +++ b/drivers/s390/char/con3215.c @@ -914,7 +914,6 @@ static int tty3215_open(struct tty_struct *tty, struct file * filp) tty_port_tty_set(&raw->port, tty); - raw->port.low_latency = 0; /* don't use bottom half for pushing chars */ /* * Start up 3215 device */ diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c index 5aff8b684eb2..013bcc331305 100644 --- a/drivers/s390/char/sclp_tty.c +++ b/drivers/s390/char/sclp_tty.c @@ -65,7 +65,6 @@ sclp_tty_open(struct tty_struct *tty, struct file *filp) { tty_port_tty_set(&sclp_port, tty); tty->driver_data = NULL; - sclp_port.low_latency = 0; return 0; } diff --git a/drivers/s390/char/sclp_vt220.c b/drivers/s390/char/sclp_vt220.c index 3f9a6ef650fa..047f812d1a1c 100644 --- a/drivers/s390/char/sclp_vt220.c +++ b/drivers/s390/char/sclp_vt220.c @@ -560,7 +560,6 @@ sclp_vt220_open(struct tty_struct *tty, struct file *filp) { if (tty->count == 1) { tty_port_tty_set(&sclp_vt220_port, tty); - sclp_vt220_port.low_latency = 0; if (!tty->winsize.ws_row && !tty->winsize.ws_col) { tty->winsize.ws_row = 24; tty->winsize.ws_col = 80; diff --git a/drivers/s390/char/tty3270.c b/drivers/s390/char/tty3270.c index aec996de44d9..15692449a1c3 100644 --- a/drivers/s390/char/tty3270.c +++ b/drivers/s390/char/tty3270.c @@ -967,7 +967,6 @@ static int tty3270_install(struct tty_driver *driver, struct tty_struct *tty) tty->driver_data = tp; tty->winsize.ws_row = tp->view.rows - 2; tty->winsize.ws_col = tp->view.cols; - tp->port.low_latency = 0; tp->inattr = TF_INPUT; goto port_install; } @@ -996,7 +995,6 @@ static int tty3270_install(struct tty_driver *driver, struct tty_struct *tty) return rc; } - tp->port.low_latency = 0; tty->winsize.ws_row = tp->view.rows - 2; tty->winsize.ws_col = tp->view.cols; diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c index 13f63c01c589..18b78ea110ef 100644 --- a/drivers/tty/amiserial.c +++ b/drivers/tty/amiserial.c @@ -998,7 +998,6 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) state->custom_divisor = ss->custom_divisor; port->close_delay = ss->close_delay * HZ/100; port->closing_wait = ss->closing_wait * HZ/100; - port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0; check_and_exit: if (tty_port_initialized(port)) { @@ -1386,8 +1385,6 @@ static int rs_open(struct tty_struct *tty, struct file * filp) tty->driver_data = info; tty->port = port; - port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0; - retval = startup(tty, info); if (retval) { return retval; diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c index 509d1042825a..dfe02283ed23 100644 --- a/drivers/tty/hvc/hvcs.c +++ b/drivers/tty/hvc/hvcs.c @@ -605,7 +605,7 @@ static int hvcs_io(struct hvcs_struct *hvcsd) hvcsd->todo_mask |= HVCS_QUICK_READ; spin_unlock_irqrestore(&hvcsd->lock, flags); - /* This is synch because tty->low_latency == 1 */ + /* This is synch -- FIXME :js: it is not! */ if(got) tty_flip_buffer_push(&hvcsd->port); diff --git a/drivers/tty/ipwireless/tty.c b/drivers/tty/ipwireless/tty.c index 23584769fc29..6dacbc5e286c 100644 --- a/drivers/tty/ipwireless/tty.c +++ b/drivers/tty/ipwireless/tty.c @@ -101,7 +101,6 @@ static int ipw_open(struct tty_struct *linux_tty, struct file *filp) tty->port.tty = linux_tty; linux_tty->driver_data = tty; - tty->port.low_latency = 1; if (tty->tty_type == TTYTYPE_MODEM) ipwireless_ppp_open(tty->network); diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c index 3703987c4666..4203b64bccdb 100644 --- a/drivers/tty/mxser.c +++ b/drivers/tty/mxser.c @@ -1273,7 +1273,6 @@ static int mxser_set_serial_info(struct tty_struct *tty, (ss->flags & ASYNC_FLAGS)); port->close_delay = ss->close_delay * HZ / 100; port->closing_wait = ss->closing_wait * HZ / 100; - port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0; if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST && (ss->baud_base != info->baud_base || ss->custom_divisor != diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c index 182e0ccd60b2..d4ef88ee22d0 100644 --- a/drivers/tty/serial/ifx6x60.c +++ b/drivers/tty/serial/ifx6x60.c @@ -565,9 +565,6 @@ static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty) /* put port data into this tty */ tty->driver_data = ifx_dev; - /* allows flip string push from int context */ - port->low_latency = 1; - /* set flag to allows data transfer */ set_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags); diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c index 371569a0fd00..3c92d4e01488 100644 --- a/drivers/tty/serial/max3100.c +++ b/drivers/tty/serial/max3100.c @@ -521,9 +521,6 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios, MAX3100_STATUS_PE | MAX3100_STATUS_FE | MAX3100_STATUS_OE; - /* we are sending char from a workqueue so enable */ - s->port.state->port.low_latency = 1; - if (s->poll_time > 0) del_timer_sync(&s->timer); diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 828f9ad1be49..7dacdb6a8534 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -975,7 +975,6 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, port->closing_wait = closing_wait; if (new_info->xmit_fifo_size) uport->fifosize = new_info->xmit_fifo_size; - port->low_latency = (uport->flags & UPF_LOW_LATENCY) ? 1 : 0; check_and_exit: retval = 0; @@ -1795,8 +1794,6 @@ static int uart_port_activate(struct tty_port *port, struct tty_struct *tty) if (!uport || uport->flags & UPF_DEAD) return -ENXIO; - port->low_latency = (uport->flags & UPF_LOW_LATENCY) ? 1 : 0; - /* * Start up the serial port. */ diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c index c0b384e3ed4d..644173786bf0 100644 --- a/drivers/tty/synclink_gt.c +++ b/drivers/tty/synclink_gt.c @@ -672,7 +672,6 @@ static int open(struct tty_struct *tty, struct file *filp) DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count)); mutex_lock(&info->port.mutex); - info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0; spin_lock_irqsave(&info->netlock, flags); if (info->netcount) { diff --git a/include/linux/tty.h b/include/linux/tty.h index 12be8b16cdef..b57f6812b3ba 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -240,8 +240,7 @@ struct tty_port { wait_queue_head_t delta_msr_wait; /* Modem status change */ unsigned long flags; /* User TTY flags ASYNC_ */ unsigned long iflags; /* Internal flags TTY_PORT_ */ - unsigned char console:1, /* port is a console */ - low_latency:1; /* optional: tune for latency */ + unsigned char console:1; /* port is a console */ struct mutex mutex; /* Locking */ struct mutex buf_mutex; /* Buffer alloc lock */ unsigned char *xmit_buf; /* Optional buffer */ -- cgit v1.3.1 From f446776ebffb9d3fb145b8d84f7f358f64cb54d6 Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Mon, 23 Nov 2020 18:49:01 -0600 Subject: tty: Export redirect release This will be required by the pty code when it removes tty_vhangup() on master close. Signed-off-by: Corey Minyard Link: https://lore.kernel.org/r/20201124004902.1398477-2-minyard@acm.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 32 ++++++++++++++++++++++++-------- include/linux/tty.h | 1 + 2 files changed, 25 insertions(+), 8 deletions(-) (limited to 'include/linux/tty.h') diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 95ba028ef668..225f4933fbde 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -540,6 +540,28 @@ void tty_wakeup(struct tty_struct *tty) EXPORT_SYMBOL_GPL(tty_wakeup); +/** + * tty_release_redirect - Release a redirect on a pty if present + * @tty: tty device + * + * This is available to the pty code so if the master closes, if the + * slave is a redirect it can release the redirect. + */ +struct file *tty_release_redirect(struct tty_struct *tty) +{ + struct file *f = NULL; + + spin_lock(&redirect_lock); + if (redirect && file_tty(redirect) == tty) { + f = redirect; + redirect = NULL; + } + spin_unlock(&redirect_lock); + + return f; +} +EXPORT_SYMBOL_GPL(tty_release_redirect); + /** * __tty_hangup - actual handler for hangup events * @tty: tty device @@ -566,7 +588,7 @@ EXPORT_SYMBOL_GPL(tty_wakeup); static void __tty_hangup(struct tty_struct *tty, int exit_session) { struct file *cons_filp = NULL; - struct file *filp, *f = NULL; + struct file *filp, *f; struct tty_file_private *priv; int closecount = 0, n; int refs; @@ -574,13 +596,7 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session) if (!tty) return; - - spin_lock(&redirect_lock); - if (redirect && file_tty(redirect) == tty) { - f = redirect; - redirect = NULL; - } - spin_unlock(&redirect_lock); + f = tty_release_redirect(tty); tty_lock(tty); diff --git a/include/linux/tty.h b/include/linux/tty.h index b57f6812b3ba..dd6ded6138f7 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -421,6 +421,7 @@ extern void tty_kclose(struct tty_struct *tty); extern int tty_dev_name_to_number(const char *name, dev_t *number); extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout); extern void tty_ldisc_unlock(struct tty_struct *tty); +extern struct file *tty_release_redirect(struct tty_struct *tty); #else static inline void tty_kref_put(struct tty_struct *tty) { } -- cgit v1.3.1