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886 lines
22 KiB
886 lines
22 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
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* |
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* Modified by Fred N. van Kempen, 01/29/93, to add line disciplines |
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* which can be dynamically activated and de-activated by the line |
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* discipline handling modules (like SLIP). |
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*/ |
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#include <linux/types.h> |
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#include <linux/termios.h> |
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#include <linux/errno.h> |
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#include <linux/sched/signal.h> |
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#include <linux/kernel.h> |
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#include <linux/major.h> |
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#include <linux/tty.h> |
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#include <linux/fcntl.h> |
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#include <linux/string.h> |
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#include <linux/mm.h> |
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#include <linux/module.h> |
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#include <linux/bitops.h> |
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#include <linux/mutex.h> |
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#include <linux/compat.h> |
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#include <asm/io.h> |
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#include <linux/uaccess.h> |
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#undef TTY_DEBUG_WAIT_UNTIL_SENT |
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#ifdef TTY_DEBUG_WAIT_UNTIL_SENT |
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# define tty_debug_wait_until_sent(tty, f, args...) tty_debug(tty, f, ##args) |
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#else |
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# define tty_debug_wait_until_sent(tty, f, args...) do {} while (0) |
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#endif |
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#undef DEBUG |
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/* |
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* Internal flag options for termios setting behavior |
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*/ |
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#define TERMIOS_FLUSH 1 |
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#define TERMIOS_WAIT 2 |
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#define TERMIOS_TERMIO 4 |
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#define TERMIOS_OLD 8 |
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/** |
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* tty_chars_in_buffer - characters pending |
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* @tty: terminal |
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* |
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* Return the number of bytes of data in the device private |
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* output queue. If no private method is supplied there is assumed |
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* to be no queue on the device. |
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*/ |
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int tty_chars_in_buffer(struct tty_struct *tty) |
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{ |
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if (tty->ops->chars_in_buffer) |
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return tty->ops->chars_in_buffer(tty); |
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else |
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return 0; |
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} |
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EXPORT_SYMBOL(tty_chars_in_buffer); |
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/** |
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* tty_write_room - write queue space |
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* @tty: terminal |
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* |
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* Return the number of bytes that can be queued to this device |
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* at the present time. The result should be treated as a guarantee |
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* and the driver cannot offer a value it later shrinks by more than |
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* the number of bytes written. If no method is provided 2K is always |
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* returned and data may be lost as there will be no flow control. |
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*/ |
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int tty_write_room(struct tty_struct *tty) |
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{ |
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if (tty->ops->write_room) |
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return tty->ops->write_room(tty); |
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return 2048; |
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} |
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EXPORT_SYMBOL(tty_write_room); |
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/** |
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* tty_driver_flush_buffer - discard internal buffer |
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* @tty: terminal |
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* |
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* Discard the internal output buffer for this device. If no method |
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* is provided then either the buffer cannot be hardware flushed or |
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* there is no buffer driver side. |
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*/ |
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void tty_driver_flush_buffer(struct tty_struct *tty) |
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{ |
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if (tty->ops->flush_buffer) |
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tty->ops->flush_buffer(tty); |
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} |
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EXPORT_SYMBOL(tty_driver_flush_buffer); |
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/** |
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* tty_throttle - flow control |
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* @tty: terminal |
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* |
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* Indicate that a tty should stop transmitting data down the stack. |
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* Takes the termios rwsem to protect against parallel throttle/unthrottle |
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* and also to ensure the driver can consistently reference its own |
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* termios data at this point when implementing software flow control. |
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*/ |
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void tty_throttle(struct tty_struct *tty) |
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{ |
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down_write(&tty->termios_rwsem); |
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/* check TTY_THROTTLED first so it indicates our state */ |
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if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && |
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tty->ops->throttle) |
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tty->ops->throttle(tty); |
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tty->flow_change = 0; |
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up_write(&tty->termios_rwsem); |
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} |
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EXPORT_SYMBOL(tty_throttle); |
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/** |
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* tty_unthrottle - flow control |
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* @tty: terminal |
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* |
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* Indicate that a tty may continue transmitting data down the stack. |
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* Takes the termios rwsem to protect against parallel throttle/unthrottle |
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* and also to ensure the driver can consistently reference its own |
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* termios data at this point when implementing software flow control. |
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* |
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* Drivers should however remember that the stack can issue a throttle, |
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* then change flow control method, then unthrottle. |
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*/ |
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void tty_unthrottle(struct tty_struct *tty) |
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{ |
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down_write(&tty->termios_rwsem); |
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if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && |
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tty->ops->unthrottle) |
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tty->ops->unthrottle(tty); |
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tty->flow_change = 0; |
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up_write(&tty->termios_rwsem); |
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} |
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EXPORT_SYMBOL(tty_unthrottle); |
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/** |
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* tty_throttle_safe - flow control |
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* @tty: terminal |
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* |
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* Similar to tty_throttle() but will only attempt throttle |
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* if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental |
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* throttle due to race conditions when throttling is conditional |
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* on factors evaluated prior to throttling. |
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* |
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* Returns 0 if tty is throttled (or was already throttled) |
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*/ |
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int tty_throttle_safe(struct tty_struct *tty) |
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{ |
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int ret = 0; |
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mutex_lock(&tty->throttle_mutex); |
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if (!tty_throttled(tty)) { |
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if (tty->flow_change != TTY_THROTTLE_SAFE) |
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ret = 1; |
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else { |
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set_bit(TTY_THROTTLED, &tty->flags); |
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if (tty->ops->throttle) |
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tty->ops->throttle(tty); |
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} |
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} |
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mutex_unlock(&tty->throttle_mutex); |
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return ret; |
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} |
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/** |
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* tty_unthrottle_safe - flow control |
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* @tty: terminal |
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* |
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* Similar to tty_unthrottle() but will only attempt unthrottle |
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* if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental |
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* unthrottle due to race conditions when unthrottling is conditional |
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* on factors evaluated prior to unthrottling. |
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* |
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* Returns 0 if tty is unthrottled (or was already unthrottled) |
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*/ |
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int tty_unthrottle_safe(struct tty_struct *tty) |
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{ |
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int ret = 0; |
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mutex_lock(&tty->throttle_mutex); |
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if (tty_throttled(tty)) { |
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if (tty->flow_change != TTY_UNTHROTTLE_SAFE) |
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ret = 1; |
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else { |
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clear_bit(TTY_THROTTLED, &tty->flags); |
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if (tty->ops->unthrottle) |
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tty->ops->unthrottle(tty); |
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} |
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} |
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mutex_unlock(&tty->throttle_mutex); |
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return ret; |
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} |
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/** |
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* tty_wait_until_sent - wait for I/O to finish |
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* @tty: tty we are waiting for |
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* @timeout: how long we will wait |
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* |
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* Wait for characters pending in a tty driver to hit the wire, or |
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* for a timeout to occur (eg due to flow control) |
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* |
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* Locking: none |
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*/ |
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void tty_wait_until_sent(struct tty_struct *tty, long timeout) |
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{ |
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tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); |
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if (!timeout) |
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timeout = MAX_SCHEDULE_TIMEOUT; |
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timeout = wait_event_interruptible_timeout(tty->write_wait, |
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!tty_chars_in_buffer(tty), timeout); |
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if (timeout <= 0) |
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return; |
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if (timeout == MAX_SCHEDULE_TIMEOUT) |
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timeout = 0; |
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if (tty->ops->wait_until_sent) |
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tty->ops->wait_until_sent(tty, timeout); |
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} |
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EXPORT_SYMBOL(tty_wait_until_sent); |
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/* |
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* Termios Helper Methods |
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*/ |
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static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) |
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{ |
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struct ktermios *termios = &tty->termios; |
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struct ktermios *locked = &tty->termios_locked; |
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int i; |
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#define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) |
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NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); |
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NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); |
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NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); |
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NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); |
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termios->c_line = locked->c_line ? old->c_line : termios->c_line; |
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for (i = 0; i < NCCS; i++) |
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termios->c_cc[i] = locked->c_cc[i] ? |
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old->c_cc[i] : termios->c_cc[i]; |
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/* FIXME: What should we do for i/ospeed */ |
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} |
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/** |
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* tty_termios_copy_hw - copy hardware settings |
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* @new: New termios |
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* @old: Old termios |
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* |
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* Propagate the hardware specific terminal setting bits from |
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* the old termios structure to the new one. This is used in cases |
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* where the hardware does not support reconfiguration or as a helper |
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* in some cases where only minimal reconfiguration is supported |
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*/ |
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void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) |
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{ |
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/* The bits a dumb device handles in software. Smart devices need |
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to always provide a set_termios method */ |
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new->c_cflag &= HUPCL | CREAD | CLOCAL; |
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new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); |
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new->c_ispeed = old->c_ispeed; |
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new->c_ospeed = old->c_ospeed; |
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} |
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EXPORT_SYMBOL(tty_termios_copy_hw); |
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/** |
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* tty_termios_hw_change - check for setting change |
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* @a: termios |
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* @b: termios to compare |
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* |
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* Check if any of the bits that affect a dumb device have changed |
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* between the two termios structures, or a speed change is needed. |
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*/ |
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int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) |
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{ |
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if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) |
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return 1; |
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if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) |
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return 1; |
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return 0; |
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} |
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EXPORT_SYMBOL(tty_termios_hw_change); |
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/** |
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* tty_set_termios - update termios values |
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* @tty: tty to update |
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* @new_termios: desired new value |
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* |
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* Perform updates to the termios values set on this terminal. |
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* A master pty's termios should never be set. |
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* |
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* Locking: termios_rwsem |
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*/ |
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int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) |
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{ |
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struct ktermios old_termios; |
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struct tty_ldisc *ld; |
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WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && |
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tty->driver->subtype == PTY_TYPE_MASTER); |
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/* |
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* Perform the actual termios internal changes under lock. |
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*/ |
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/* FIXME: we need to decide on some locking/ordering semantics |
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for the set_termios notification eventually */ |
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down_write(&tty->termios_rwsem); |
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old_termios = tty->termios; |
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tty->termios = *new_termios; |
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unset_locked_termios(tty, &old_termios); |
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if (tty->ops->set_termios) |
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tty->ops->set_termios(tty, &old_termios); |
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else |
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tty_termios_copy_hw(&tty->termios, &old_termios); |
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ld = tty_ldisc_ref(tty); |
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if (ld != NULL) { |
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if (ld->ops->set_termios) |
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ld->ops->set_termios(tty, &old_termios); |
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tty_ldisc_deref(ld); |
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} |
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up_write(&tty->termios_rwsem); |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(tty_set_termios); |
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/** |
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* set_termios - set termios values for a tty |
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* @tty: terminal device |
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* @arg: user data |
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* @opt: option information |
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* |
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* Helper function to prepare termios data and run necessary other |
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* functions before using tty_set_termios to do the actual changes. |
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* |
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* Locking: |
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* Called functions take ldisc and termios_rwsem locks |
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*/ |
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static int set_termios(struct tty_struct *tty, void __user *arg, int opt) |
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{ |
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struct ktermios tmp_termios; |
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struct tty_ldisc *ld; |
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int retval = tty_check_change(tty); |
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if (retval) |
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return retval; |
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down_read(&tty->termios_rwsem); |
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tmp_termios = tty->termios; |
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up_read(&tty->termios_rwsem); |
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if (opt & TERMIOS_TERMIO) { |
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if (user_termio_to_kernel_termios(&tmp_termios, |
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(struct termio __user *)arg)) |
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return -EFAULT; |
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#ifdef TCGETS2 |
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} else if (opt & TERMIOS_OLD) { |
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if (user_termios_to_kernel_termios_1(&tmp_termios, |
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(struct termios __user *)arg)) |
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return -EFAULT; |
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} else { |
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if (user_termios_to_kernel_termios(&tmp_termios, |
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(struct termios2 __user *)arg)) |
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return -EFAULT; |
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} |
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#else |
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} else if (user_termios_to_kernel_termios(&tmp_termios, |
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(struct termios __user *)arg)) |
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return -EFAULT; |
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#endif |
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/* If old style Bfoo values are used then load c_ispeed/c_ospeed |
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* with the real speed so its unconditionally usable */ |
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tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); |
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tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); |
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ld = tty_ldisc_ref(tty); |
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if (ld != NULL) { |
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if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) |
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ld->ops->flush_buffer(tty); |
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tty_ldisc_deref(ld); |
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} |
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if (opt & TERMIOS_WAIT) { |
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tty_wait_until_sent(tty, 0); |
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if (signal_pending(current)) |
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return -ERESTARTSYS; |
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} |
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tty_set_termios(tty, &tmp_termios); |
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/* FIXME: Arguably if tmp_termios == tty->termios AND the |
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actual requested termios was not tmp_termios then we may |
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want to return an error as no user requested change has |
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succeeded */ |
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return 0; |
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} |
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static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) |
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{ |
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down_read(&tty->termios_rwsem); |
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*kterm = tty->termios; |
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up_read(&tty->termios_rwsem); |
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} |
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static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) |
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{ |
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down_read(&tty->termios_rwsem); |
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*kterm = tty->termios_locked; |
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up_read(&tty->termios_rwsem); |
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} |
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static int get_termio(struct tty_struct *tty, struct termio __user *termio) |
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{ |
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struct ktermios kterm; |
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copy_termios(tty, &kterm); |
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if (kernel_termios_to_user_termio(termio, &kterm)) |
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return -EFAULT; |
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return 0; |
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} |
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#ifdef TIOCGETP |
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/* |
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* These are deprecated, but there is limited support.. |
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* |
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* The "sg_flags" translation is a joke.. |
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*/ |
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static int get_sgflags(struct tty_struct *tty) |
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{ |
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int flags = 0; |
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if (!L_ICANON(tty)) { |
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if (L_ISIG(tty)) |
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flags |= 0x02; /* cbreak */ |
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else |
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flags |= 0x20; /* raw */ |
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} |
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if (L_ECHO(tty)) |
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flags |= 0x08; /* echo */ |
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if (O_OPOST(tty)) |
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if (O_ONLCR(tty)) |
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flags |= 0x10; /* crmod */ |
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return flags; |
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} |
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static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
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{ |
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struct sgttyb tmp; |
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down_read(&tty->termios_rwsem); |
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tmp.sg_ispeed = tty->termios.c_ispeed; |
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tmp.sg_ospeed = tty->termios.c_ospeed; |
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tmp.sg_erase = tty->termios.c_cc[VERASE]; |
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tmp.sg_kill = tty->termios.c_cc[VKILL]; |
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tmp.sg_flags = get_sgflags(tty); |
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up_read(&tty->termios_rwsem); |
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return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
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} |
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static void set_sgflags(struct ktermios *termios, int flags) |
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{ |
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termios->c_iflag = ICRNL | IXON; |
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termios->c_oflag = 0; |
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termios->c_lflag = ISIG | ICANON; |
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if (flags & 0x02) { /* cbreak */ |
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termios->c_iflag = 0; |
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termios->c_lflag &= ~ICANON; |
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} |
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if (flags & 0x08) { /* echo */ |
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termios->c_lflag |= ECHO | ECHOE | ECHOK | |
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ECHOCTL | ECHOKE | IEXTEN; |
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} |
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if (flags & 0x10) { /* crmod */ |
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termios->c_oflag |= OPOST | ONLCR; |
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} |
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if (flags & 0x20) { /* raw */ |
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termios->c_iflag = 0; |
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termios->c_lflag &= ~(ISIG | ICANON); |
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} |
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if (!(termios->c_lflag & ICANON)) { |
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termios->c_cc[VMIN] = 1; |
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termios->c_cc[VTIME] = 0; |
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} |
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} |
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/** |
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* set_sgttyb - set legacy terminal values |
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* @tty: tty structure |
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* @sgttyb: pointer to old style terminal structure |
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* |
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* Updates a terminal from the legacy BSD style terminal information |
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* structure. |
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* |
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* Locking: termios_rwsem |
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*/ |
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static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) |
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{ |
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int retval; |
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struct sgttyb tmp; |
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struct ktermios termios; |
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retval = tty_check_change(tty); |
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if (retval) |
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return retval; |
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if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) |
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return -EFAULT; |
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down_write(&tty->termios_rwsem); |
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termios = tty->termios; |
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termios.c_cc[VERASE] = tmp.sg_erase; |
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termios.c_cc[VKILL] = tmp.sg_kill; |
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set_sgflags(&termios, tmp.sg_flags); |
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/* Try and encode into Bfoo format */ |
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#ifdef BOTHER |
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tty_termios_encode_baud_rate(&termios, termios.c_ispeed, |
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termios.c_ospeed); |
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#endif |
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up_write(&tty->termios_rwsem); |
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tty_set_termios(tty, &termios); |
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return 0; |
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} |
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#endif |
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#ifdef TIOCGETC |
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static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
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{ |
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struct tchars tmp; |
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|
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down_read(&tty->termios_rwsem); |
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tmp.t_intrc = tty->termios.c_cc[VINTR]; |
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tmp.t_quitc = tty->termios.c_cc[VQUIT]; |
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tmp.t_startc = tty->termios.c_cc[VSTART]; |
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tmp.t_stopc = tty->termios.c_cc[VSTOP]; |
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tmp.t_eofc = tty->termios.c_cc[VEOF]; |
|
tmp.t_brkc = tty->termios.c_cc[VEOL2]; /* what is brkc anyway? */ |
|
up_read(&tty->termios_rwsem); |
|
return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
|
} |
|
|
|
static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) |
|
{ |
|
struct tchars tmp; |
|
|
|
if (copy_from_user(&tmp, tchars, sizeof(tmp))) |
|
return -EFAULT; |
|
down_write(&tty->termios_rwsem); |
|
tty->termios.c_cc[VINTR] = tmp.t_intrc; |
|
tty->termios.c_cc[VQUIT] = tmp.t_quitc; |
|
tty->termios.c_cc[VSTART] = tmp.t_startc; |
|
tty->termios.c_cc[VSTOP] = tmp.t_stopc; |
|
tty->termios.c_cc[VEOF] = tmp.t_eofc; |
|
tty->termios.c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ |
|
up_write(&tty->termios_rwsem); |
|
return 0; |
|
} |
|
#endif |
|
|
|
#ifdef TIOCGLTC |
|
static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
|
{ |
|
struct ltchars tmp; |
|
|
|
down_read(&tty->termios_rwsem); |
|
tmp.t_suspc = tty->termios.c_cc[VSUSP]; |
|
/* what is dsuspc anyway? */ |
|
tmp.t_dsuspc = tty->termios.c_cc[VSUSP]; |
|
tmp.t_rprntc = tty->termios.c_cc[VREPRINT]; |
|
/* what is flushc anyway? */ |
|
tmp.t_flushc = tty->termios.c_cc[VEOL2]; |
|
tmp.t_werasc = tty->termios.c_cc[VWERASE]; |
|
tmp.t_lnextc = tty->termios.c_cc[VLNEXT]; |
|
up_read(&tty->termios_rwsem); |
|
return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; |
|
} |
|
|
|
static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) |
|
{ |
|
struct ltchars tmp; |
|
|
|
if (copy_from_user(&tmp, ltchars, sizeof(tmp))) |
|
return -EFAULT; |
|
|
|
down_write(&tty->termios_rwsem); |
|
tty->termios.c_cc[VSUSP] = tmp.t_suspc; |
|
/* what is dsuspc anyway? */ |
|
tty->termios.c_cc[VEOL2] = tmp.t_dsuspc; |
|
tty->termios.c_cc[VREPRINT] = tmp.t_rprntc; |
|
/* what is flushc anyway? */ |
|
tty->termios.c_cc[VEOL2] = tmp.t_flushc; |
|
tty->termios.c_cc[VWERASE] = tmp.t_werasc; |
|
tty->termios.c_cc[VLNEXT] = tmp.t_lnextc; |
|
up_write(&tty->termios_rwsem); |
|
return 0; |
|
} |
|
#endif |
|
|
|
/** |
|
* tty_change_softcar - carrier change ioctl helper |
|
* @tty: tty to update |
|
* @arg: enable/disable CLOCAL |
|
* |
|
* Perform a change to the CLOCAL state and call into the driver |
|
* layer to make it visible. All done with the termios rwsem |
|
*/ |
|
|
|
static int tty_change_softcar(struct tty_struct *tty, int arg) |
|
{ |
|
int ret = 0; |
|
int bit = arg ? CLOCAL : 0; |
|
struct ktermios old; |
|
|
|
down_write(&tty->termios_rwsem); |
|
old = tty->termios; |
|
tty->termios.c_cflag &= ~CLOCAL; |
|
tty->termios.c_cflag |= bit; |
|
if (tty->ops->set_termios) |
|
tty->ops->set_termios(tty, &old); |
|
if (C_CLOCAL(tty) != bit) |
|
ret = -EINVAL; |
|
up_write(&tty->termios_rwsem); |
|
return ret; |
|
} |
|
|
|
/** |
|
* tty_mode_ioctl - mode related ioctls |
|
* @tty: tty for the ioctl |
|
* @file: file pointer for the tty |
|
* @cmd: command |
|
* @arg: ioctl argument |
|
* |
|
* Perform non line discipline specific mode control ioctls. This |
|
* is designed to be called by line disciplines to ensure they provide |
|
* consistent mode setting. |
|
*/ |
|
|
|
int tty_mode_ioctl(struct tty_struct *tty, struct file *file, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
struct tty_struct *real_tty; |
|
void __user *p = (void __user *)arg; |
|
int ret = 0; |
|
struct ktermios kterm; |
|
|
|
BUG_ON(file == NULL); |
|
|
|
if (tty->driver->type == TTY_DRIVER_TYPE_PTY && |
|
tty->driver->subtype == PTY_TYPE_MASTER) |
|
real_tty = tty->link; |
|
else |
|
real_tty = tty; |
|
|
|
switch (cmd) { |
|
#ifdef TIOCGETP |
|
case TIOCGETP: |
|
return get_sgttyb(real_tty, (struct sgttyb __user *) arg); |
|
case TIOCSETP: |
|
case TIOCSETN: |
|
return set_sgttyb(real_tty, (struct sgttyb __user *) arg); |
|
#endif |
|
#ifdef TIOCGETC |
|
case TIOCGETC: |
|
return get_tchars(real_tty, p); |
|
case TIOCSETC: |
|
return set_tchars(real_tty, p); |
|
#endif |
|
#ifdef TIOCGLTC |
|
case TIOCGLTC: |
|
return get_ltchars(real_tty, p); |
|
case TIOCSLTC: |
|
return set_ltchars(real_tty, p); |
|
#endif |
|
case TCSETSF: |
|
return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD); |
|
case TCSETSW: |
|
return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD); |
|
case TCSETS: |
|
return set_termios(real_tty, p, TERMIOS_OLD); |
|
#ifndef TCGETS2 |
|
case TCGETS: |
|
copy_termios(real_tty, &kterm); |
|
if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) |
|
ret = -EFAULT; |
|
return ret; |
|
#else |
|
case TCGETS: |
|
copy_termios(real_tty, &kterm); |
|
if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) |
|
ret = -EFAULT; |
|
return ret; |
|
case TCGETS2: |
|
copy_termios(real_tty, &kterm); |
|
if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) |
|
ret = -EFAULT; |
|
return ret; |
|
case TCSETSF2: |
|
return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); |
|
case TCSETSW2: |
|
return set_termios(real_tty, p, TERMIOS_WAIT); |
|
case TCSETS2: |
|
return set_termios(real_tty, p, 0); |
|
#endif |
|
case TCGETA: |
|
return get_termio(real_tty, p); |
|
case TCSETAF: |
|
return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); |
|
case TCSETAW: |
|
return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); |
|
case TCSETA: |
|
return set_termios(real_tty, p, TERMIOS_TERMIO); |
|
#ifndef TCGETS2 |
|
case TIOCGLCKTRMIOS: |
|
copy_termios_locked(real_tty, &kterm); |
|
if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) |
|
ret = -EFAULT; |
|
return ret; |
|
case TIOCSLCKTRMIOS: |
|
if (!capable(CAP_SYS_ADMIN)) |
|
return -EPERM; |
|
copy_termios_locked(real_tty, &kterm); |
|
if (user_termios_to_kernel_termios(&kterm, |
|
(struct termios __user *) arg)) |
|
return -EFAULT; |
|
down_write(&real_tty->termios_rwsem); |
|
real_tty->termios_locked = kterm; |
|
up_write(&real_tty->termios_rwsem); |
|
return 0; |
|
#else |
|
case TIOCGLCKTRMIOS: |
|
copy_termios_locked(real_tty, &kterm); |
|
if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) |
|
ret = -EFAULT; |
|
return ret; |
|
case TIOCSLCKTRMIOS: |
|
if (!capable(CAP_SYS_ADMIN)) |
|
return -EPERM; |
|
copy_termios_locked(real_tty, &kterm); |
|
if (user_termios_to_kernel_termios_1(&kterm, |
|
(struct termios __user *) arg)) |
|
return -EFAULT; |
|
down_write(&real_tty->termios_rwsem); |
|
real_tty->termios_locked = kterm; |
|
up_write(&real_tty->termios_rwsem); |
|
return ret; |
|
#endif |
|
#ifdef TCGETX |
|
case TCGETX: |
|
case TCSETX: |
|
case TCSETXW: |
|
case TCSETXF: |
|
return -ENOTTY; |
|
#endif |
|
case TIOCGSOFTCAR: |
|
copy_termios(real_tty, &kterm); |
|
ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, |
|
(int __user *)arg); |
|
return ret; |
|
case TIOCSSOFTCAR: |
|
if (get_user(arg, (unsigned int __user *) arg)) |
|
return -EFAULT; |
|
return tty_change_softcar(real_tty, arg); |
|
default: |
|
return -ENOIOCTLCMD; |
|
} |
|
} |
|
EXPORT_SYMBOL_GPL(tty_mode_ioctl); |
|
|
|
|
|
/* Caller guarantees ldisc reference is held */ |
|
static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg) |
|
{ |
|
struct tty_ldisc *ld = tty->ldisc; |
|
|
|
switch (arg) { |
|
case TCIFLUSH: |
|
if (ld && ld->ops->flush_buffer) { |
|
ld->ops->flush_buffer(tty); |
|
tty_unthrottle(tty); |
|
} |
|
break; |
|
case TCIOFLUSH: |
|
if (ld && ld->ops->flush_buffer) { |
|
ld->ops->flush_buffer(tty); |
|
tty_unthrottle(tty); |
|
} |
|
fallthrough; |
|
case TCOFLUSH: |
|
tty_driver_flush_buffer(tty); |
|
break; |
|
default: |
|
return -EINVAL; |
|
} |
|
return 0; |
|
} |
|
|
|
int tty_perform_flush(struct tty_struct *tty, unsigned long arg) |
|
{ |
|
struct tty_ldisc *ld; |
|
int retval = tty_check_change(tty); |
|
if (retval) |
|
return retval; |
|
|
|
ld = tty_ldisc_ref_wait(tty); |
|
retval = __tty_perform_flush(tty, arg); |
|
if (ld) |
|
tty_ldisc_deref(ld); |
|
return retval; |
|
} |
|
EXPORT_SYMBOL_GPL(tty_perform_flush); |
|
|
|
int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
int retval; |
|
|
|
switch (cmd) { |
|
case TCXONC: |
|
retval = tty_check_change(tty); |
|
if (retval) |
|
return retval; |
|
switch (arg) { |
|
case TCOOFF: |
|
spin_lock_irq(&tty->flow_lock); |
|
if (!tty->flow_stopped) { |
|
tty->flow_stopped = 1; |
|
__stop_tty(tty); |
|
} |
|
spin_unlock_irq(&tty->flow_lock); |
|
break; |
|
case TCOON: |
|
spin_lock_irq(&tty->flow_lock); |
|
if (tty->flow_stopped) { |
|
tty->flow_stopped = 0; |
|
__start_tty(tty); |
|
} |
|
spin_unlock_irq(&tty->flow_lock); |
|
break; |
|
case TCIOFF: |
|
if (STOP_CHAR(tty) != __DISABLED_CHAR) |
|
retval = tty_send_xchar(tty, STOP_CHAR(tty)); |
|
break; |
|
case TCION: |
|
if (START_CHAR(tty) != __DISABLED_CHAR) |
|
retval = tty_send_xchar(tty, START_CHAR(tty)); |
|
break; |
|
default: |
|
return -EINVAL; |
|
} |
|
return retval; |
|
case TCFLSH: |
|
retval = tty_check_change(tty); |
|
if (retval) |
|
return retval; |
|
return __tty_perform_flush(tty, arg); |
|
default: |
|
/* Try the mode commands */ |
|
return tty_mode_ioctl(tty, file, cmd, arg); |
|
} |
|
} |
|
EXPORT_SYMBOL(n_tty_ioctl_helper);
|
|
|