/* * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds * * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines * which can be dynamically activated and de-activated by the line * discipline handling modules (like SLIP). */ #include <linux/types.h>#include <linux/termios.h>#include <linux/errno.h>#include <linux/sched/signal.h>#include <linux/kernel.h>#include <linux/major.h>#include <linux/tty.h>#include <linux/fcntl.h>#include <linux/string.h>#include <linux/mm.h>#include <linux/module.h>#include <linux/bitops.h>#include <linux/mutex.h>#include <linux/compat.h> #include <asm/io.h>#include <linux/uaccess.h> #undef TTY_DEBUG_WAIT_UNTIL_SENT #ifdef TTY_DEBUG_WAIT_UNTIL_SENT# define tty_debug_wait_until_sent(tty, f, args...) tty_debug(tty, f, ##args)#else# define tty_debug_wait_until_sent(tty, f, args...) do {} while (0)#endif #undef DEBUG /* * Internal flag options for termios setting behavior */#define TERMIOS_FLUSH 1#define TERMIOS_WAIT 2#define TERMIOS_TERMIO 4#define TERMIOS_OLD 8 /** * tty_chars_in_buffer - characters pending * @tty: terminal * * Return the number of bytes of data in the device private * output queue. If no private method is supplied there is assumed * to be no queue on the device. */ int tty_chars_in_buffer(struct tty_struct *tty){ if (tty->ops->chars_in_buffer) return tty->ops->chars_in_buffer(tty); else return 0;}EXPORT_SYMBOL(tty_chars_in_buffer); /** * tty_write_room - write queue space * @tty: terminal * * Return the number of bytes that can be queued to this device * at the present time. The result should be treated as a guarantee * and the driver cannot offer a value it later shrinks by more than * the number of bytes written. If no method is provided 2K is always * returned and data may be lost as there will be no flow control. */ int tty_write_room(struct tty_struct *tty){ if (tty->ops->write_room) return tty->ops->write_room(tty); return 2048;}EXPORT_SYMBOL(tty_write_room); /** * tty_driver_flush_buffer - discard internal buffer * @tty: terminal * * Discard the internal output buffer for this device. If no method * is provided then either the buffer cannot be hardware flushed or * there is no buffer driver side. */void tty_driver_flush_buffer(struct tty_struct *tty){ if (tty->ops->flush_buffer) tty->ops->flush_buffer(tty);}EXPORT_SYMBOL(tty_driver_flush_buffer); /** * tty_throttle - flow control * @tty: terminal * * Indicate that a tty should stop transmitting data down the stack. * Takes the termios rwsem to protect against parallel throttle/unthrottle * and also to ensure the driver can consistently reference its own * termios data at this point when implementing software flow control. */ void tty_throttle(struct tty_struct *tty){ down_write(&tty->termios_rwsem); /* check TTY_THROTTLED first so it indicates our state */ if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && tty->ops->throttle) tty->ops->throttle(tty); tty->flow_change = 0; up_write(&tty->termios_rwsem);}EXPORT_SYMBOL(tty_throttle); /** * tty_unthrottle - flow control * @tty: terminal * * Indicate that a tty may continue transmitting data down the stack. * Takes the termios rwsem to protect against parallel throttle/unthrottle * and also to ensure the driver can consistently reference its own * termios data at this point when implementing software flow control. * * Drivers should however remember that the stack can issue a throttle, * then change flow control method, then unthrottle. */ void tty_unthrottle(struct tty_struct *tty){ down_write(&tty->termios_rwsem); if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && tty->ops->unthrottle) tty->ops->unthrottle(tty); tty->flow_change = 0; up_write(&tty->termios_rwsem);}EXPORT_SYMBOL(tty_unthrottle); /** * tty_throttle_safe - flow control * @tty: terminal * * Similar to tty_throttle() but will only attempt throttle * if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental * throttle due to race conditions when throttling is conditional * on factors evaluated prior to throttling. * * Returns 0 if tty is throttled (or was already throttled) */ int tty_throttle_safe(struct tty_struct *tty){ int ret = 0; mutex_lock(&tty->throttle_mutex); if (!tty_throttled(tty)) { if (tty->flow_change != TTY_THROTTLE_SAFE) ret = 1; else { set_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->throttle) tty->ops->throttle(tty); } } mutex_unlock(&tty->throttle_mutex); return ret;} /** * tty_unthrottle_safe - flow control * @tty: terminal * * Similar to tty_unthrottle() but will only attempt unthrottle * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental * unthrottle due to race conditions when unthrottling is conditional * on factors evaluated prior to unthrottling. * * Returns 0 if tty is unthrottled (or was already unthrottled) */ int tty_unthrottle_safe(struct tty_struct *tty){ int ret = 0; mutex_lock(&tty->throttle_mutex); if (tty_throttled(tty)) { if (tty->flow_change != TTY_UNTHROTTLE_SAFE) ret = 1; else { clear_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->unthrottle) tty->ops->unthrottle(tty); } } mutex_unlock(&tty->throttle_mutex); return ret;} /** * tty_wait_until_sent - wait for I/O to finish * @tty: tty we are waiting for * @timeout: how long we will wait * * Wait for characters pending in a tty driver to hit the wire, or * for a timeout to occur (eg due to flow control) * * Locking: none */ void tty_wait_until_sent(struct tty_struct *tty, long timeout){ tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); if (!timeout) timeout = MAX_SCHEDULE_TIMEOUT; timeout = wait_event_interruptible_timeout(tty->write_wait, !tty_chars_in_buffer(tty), timeout); if (timeout <= 0) return; if (timeout == MAX_SCHEDULE_TIMEOUT) timeout = 0; if (tty->ops->wait_until_sent) tty->ops->wait_until_sent(tty, timeout);}EXPORT_SYMBOL(tty_wait_until_sent); /* * Termios Helper Methods */ static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old){ struct ktermios *termios = &tty->termios; struct ktermios *locked = &tty->termios_locked; int i; #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); termios->c_line = locked->c_line ? old->c_line : termios->c_line; for (i = 0; i < NCCS; i++) termios->c_cc[i] = locked->c_cc[i] ? old->c_cc[i] : termios->c_cc[i]; /* FIXME: What should we do for i/ospeed */} /** * tty_termios_copy_hw - copy hardware settings * @new: New termios * @old: Old termios * * Propagate the hardware specific terminal setting bits from * the old termios structure to the new one. This is used in cases * where the hardware does not support reconfiguration or as a helper * in some cases where only minimal reconfiguration is supported */ void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old){ /* The bits a dumb device handles in software. Smart devices need to always provide a set_termios method */ new->c_cflag &= HUPCL | CREAD | CLOCAL; new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); new->c_ispeed = old->c_ispeed; new->c_ospeed = old->c_ospeed;}EXPORT_SYMBOL(tty_termios_copy_hw); /** * tty_termios_hw_change - check for setting change * @a: termios * @b: termios to compare * * Check if any of the bits that affect a dumb device have changed * between the two termios structures, or a speed change is needed. */ int tty_termios_hw_change(struct ktermios *a, struct ktermios *b){ if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) return 1; if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) return 1; return 0;}EXPORT_SYMBOL(tty_termios_hw_change); /** * tty_set_termios - update termios values * @tty: tty to update * @new_termios: desired new value * * Perform updates to the termios values set on this terminal. * A master pty's termios should never be set. * * Locking: termios_rwsem */ int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios){ struct ktermios old_termios; struct tty_ldisc *ld; WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && tty->driver->subtype == PTY_TYPE_MASTER); /* * Perform the actual termios internal changes under lock. */ /* FIXME: we need to decide on some locking/ordering semantics for the set_termios notification eventually */ down_write(&tty->termios_rwsem); old_termios = tty->termios; tty->termios = *new_termios; unset_locked_termios(tty, &old_termios); if (tty->ops->set_termios) tty->ops->set_termios(tty, &old_termios); else tty_termios_copy_hw(&tty->termios, &old_termios); ld = tty_ldisc_ref(tty); if (ld != NULL) { if (ld->ops->set_termios) ld->ops->set_termios(tty, &old_termios); tty_ldisc_deref(ld); } up_write(&tty->termios_rwsem); return 0;}EXPORT_SYMBOL_GPL(tty_set_termios); /** * set_termios - set termios values for a tty * @tty: terminal device * @arg: user data * @opt: option information * * Helper function to prepare termios data and run necessary other * functions before using tty_set_termios to do the actual changes. * * Locking: * Called functions take ldisc and termios_rwsem locks */ static int set_termios(struct tty_struct *tty, void __user *arg, int opt){ struct ktermios tmp_termios; struct tty_ldisc *ld; int retval = tty_check_change(tty); if (retval) return retval; down_read(&tty->termios_rwsem); tmp_termios = tty->termios; up_read(&tty->termios_rwsem); if (opt & TERMIOS_TERMIO) { if (user_termio_to_kernel_termios(&tmp_termios, (struct termio __user *)arg)) return -EFAULT;#ifdef TCGETS2 } else if (opt & TERMIOS_OLD) { if (user_termios_to_kernel_termios_1(&tmp_termios, (struct termios __user *)arg)) return -EFAULT; } else { if (user_termios_to_kernel_termios(&tmp_termios, (struct termios2 __user *)arg)) return -EFAULT; }#else } else if (user_termios_to_kernel_termios(&tmp_termios, (struct termios __user *)arg)) return -EFAULT;#endif /* If old style Bfoo values are used then load c_ispeed/c_ospeed * with the real speed so its unconditionally usable */ tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty); tty_ldisc_deref(ld); } if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) return -ERESTARTSYS; } tty_set_termios(tty, &tmp_termios); /* FIXME: Arguably if tmp_termios == tty->termios AND the actual requested termios was not tmp_termios then we may want to return an error as no user requested change has succeeded */ return 0;} static void copy_termios(struct tty_struct *tty, struct ktermios *kterm){ down_read(&tty->termios_rwsem); *kterm = tty->termios; up_read(&tty->termios_rwsem);} static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm){ down_read(&tty->termios_rwsem); *kterm = tty->termios_locked; up_read(&tty->termios_rwsem);} static int get_termio(struct tty_struct *tty, struct termio __user *termio){ struct ktermios kterm; copy_termios(tty, &kterm); if (kernel_termios_to_user_termio(termio, &kterm)) return -EFAULT; return 0;} #ifdef TCGETX /** * set_termiox - set termiox fields if possible * @tty: terminal * @arg: termiox structure from user * @opt: option flags for ioctl type * * Implement the device calling points for the SYS5 termiox ioctl * interface in Linux */ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt){ struct termiox tnew; struct tty_ldisc *ld; if (tty->termiox == NULL) return -EINVAL; if (copy_from_user(&tnew, arg, sizeof(struct termiox))) return -EFAULT; ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty); tty_ldisc_deref(ld); } if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) return -ERESTARTSYS; } down_write(&tty->termios_rwsem); if (tty->ops->set_termiox) tty->ops->set_termiox(tty, &tnew); up_write(&tty->termios_rwsem); return 0;} #endif #ifdef TIOCGETP/* * These are deprecated, but there is limited support.. * * The "sg_flags" translation is a joke.. */static int get_sgflags(struct tty_struct *tty){ int flags = 0; if (!L_ICANON(tty)) {Lines 1–500 of 958. 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/* * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds * * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines * which can be dynamically activated and de-activated by the line * discipline handling modules (like SLIP). */ #include <linux/types.h> #include <linux/termios.h> #include <linux/errno.h> #include <linux/sched/signal.h> #include <linux/kernel.h> #include <linux/major.h> #include <linux/tty.h> #include <linux/fcntl.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/bitops.h> #include <linux/mutex.h> #include <linux/compat.h> #include <asm/io.h> #include <linux/uaccess.h> #undef TTY_DEBUG_WAIT_UNTIL_SENT #ifdef TTY_DEBUG_WAIT_UNTIL_SENT # define tty_debug_wait_until_sent(tty, f, args...) tty_debug(tty, f, ##args) #else # define tty_debug_wait_until_sent(tty, f, args...) do {} while (0) #endif #undef DEBUG /* * Internal flag options for termios setting behavior */ #define TERMIOS_FLUSH 1 #define TERMIOS_WAIT 2 #define TERMIOS_TERMIO 4 #define TERMIOS_OLD 8 /** * tty_chars_in_buffer - characters pending * @tty: terminal * * Return the number of bytes of data in the device private * output queue. If no private method is supplied there is assumed * to be no queue on the device. */ int tty_chars_in_buffer(struct tty_struct *tty) { if (tty->ops->chars_in_buffer) return tty->ops->chars_in_buffer(tty); else return 0; } EXPORT_SYMBOL(tty_chars_in_buffer); /** * tty_write_room - write queue space * @tty: terminal * * Return the number of bytes that can be queued to this device * at the present time. The result should be treated as a guarantee * and the driver cannot offer a value it later shrinks by more than * the number of bytes written. If no method is provided 2K is always * returned and data may be lost as there will be no flow control. */ int tty_write_room(struct tty_struct *tty) { if (tty->ops->write_room) return tty->ops->write_room(tty); return 2048; } EXPORT_SYMBOL(tty_write_room); /** * tty_driver_flush_buffer - discard internal buffer * @tty: terminal * * Discard the internal output buffer for this device. If no method * is provided then either the buffer cannot be hardware flushed or * there is no buffer driver side. */ void tty_driver_flush_buffer(struct tty_struct *tty) { if (tty->ops->flush_buffer) tty->ops->flush_buffer(tty); } EXPORT_SYMBOL(tty_driver_flush_buffer); /** * tty_throttle - flow control * @tty: terminal * * Indicate that a tty should stop transmitting data down the stack. * Takes the termios rwsem to protect against parallel throttle/unthrottle * and also to ensure the driver can consistently reference its own * termios data at this point when implementing software flow control. */ void tty_throttle(struct tty_struct *tty) { down_write(&tty->termios_rwsem); /* check TTY_THROTTLED first so it indicates our state */ if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && tty->ops->throttle) tty->ops->throttle(tty); tty->flow_change = 0; up_write(&tty->termios_rwsem); } EXPORT_SYMBOL(tty_throttle); /** * tty_unthrottle - flow control * @tty: terminal * * Indicate that a tty may continue transmitting data down the stack. * Takes the termios rwsem to protect against parallel throttle/unthrottle * and also to ensure the driver can consistently reference its own * termios data at this point when implementing software flow control. * * Drivers should however remember that the stack can issue a throttle, * then change flow control method, then unthrottle. */ void tty_unthrottle(struct tty_struct *tty) { down_write(&tty->termios_rwsem); if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && tty->ops->unthrottle) tty->ops->unthrottle(tty); tty->flow_change = 0; up_write(&tty->termios_rwsem); } EXPORT_SYMBOL(tty_unthrottle); /** * tty_throttle_safe - flow control * @tty: terminal * * Similar to tty_throttle() but will only attempt throttle * if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental * throttle due to race conditions when throttling is conditional * on factors evaluated prior to throttling. * * Returns 0 if tty is throttled (or was already throttled) */ int tty_throttle_safe(struct tty_struct *tty) { int ret = 0; mutex_lock(&tty->throttle_mutex); if (!tty_throttled(tty)) { if (tty->flow_change != TTY_THROTTLE_SAFE) ret = 1; else { set_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->throttle) tty->ops->throttle(tty); } } mutex_unlock(&tty->throttle_mutex); return ret; } /** * tty_unthrottle_safe - flow control * @tty: terminal * * Similar to tty_unthrottle() but will only attempt unthrottle * if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental * unthrottle due to race conditions when unthrottling is conditional * on factors evaluated prior to unthrottling. * * Returns 0 if tty is unthrottled (or was already unthrottled) */ int tty_unthrottle_safe(struct tty_struct *tty) { int ret = 0; mutex_lock(&tty->throttle_mutex); if (tty_throttled(tty)) { if (tty->flow_change != TTY_UNTHROTTLE_SAFE) ret = 1; else { clear_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->unthrottle) tty->ops->unthrottle(tty); } } mutex_unlock(&tty->throttle_mutex); return ret; } /** * tty_wait_until_sent - wait for I/O to finish * @tty: tty we are waiting for * @timeout: how long we will wait * * Wait for characters pending in a tty driver to hit the wire, or * for a timeout to occur (eg due to flow control) * * Locking: none */ void tty_wait_until_sent(struct tty_struct *tty, long timeout) { tty_debug_wait_until_sent(tty, "wait until sent, timeout=%ld\n", timeout); if (!timeout) timeout = MAX_SCHEDULE_TIMEOUT; timeout = wait_event_interruptible_timeout(tty->write_wait, !tty_chars_in_buffer(tty), timeout); if (timeout <= 0) return; if (timeout == MAX_SCHEDULE_TIMEOUT) timeout = 0; if (tty->ops->wait_until_sent) tty->ops->wait_until_sent(tty, timeout); } EXPORT_SYMBOL(tty_wait_until_sent); /* * Termios Helper Methods */ static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) { struct ktermios *termios = &tty->termios; struct ktermios *locked = &tty->termios_locked; int i; #define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z))) NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); termios->c_line = locked->c_line ? old->c_line : termios->c_line; for (i = 0; i < NCCS; i++) termios->c_cc[i] = locked->c_cc[i] ? old->c_cc[i] : termios->c_cc[i]; /* FIXME: What should we do for i/ospeed */ } /** * tty_termios_copy_hw - copy hardware settings * @new: New termios * @old: Old termios * * Propagate the hardware specific terminal setting bits from * the old termios structure to the new one. This is used in cases * where the hardware does not support reconfiguration or as a helper * in some cases where only minimal reconfiguration is supported */ void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old) { /* The bits a dumb device handles in software. Smart devices need to always provide a set_termios method */ new->c_cflag &= HUPCL | CREAD | CLOCAL; new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL); new->c_ispeed = old->c_ispeed; new->c_ospeed = old->c_ospeed; } EXPORT_SYMBOL(tty_termios_copy_hw); /** * tty_termios_hw_change - check for setting change * @a: termios * @b: termios to compare * * Check if any of the bits that affect a dumb device have changed * between the two termios structures, or a speed change is needed. */ int tty_termios_hw_change(struct ktermios *a, struct ktermios *b) { if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) return 1; if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) return 1; return 0; } EXPORT_SYMBOL(tty_termios_hw_change); /** * tty_set_termios - update termios values * @tty: tty to update * @new_termios: desired new value * * Perform updates to the termios values set on this terminal. * A master pty's termios should never be set. * * Locking: termios_rwsem */ int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) { struct ktermios old_termios; struct tty_ldisc *ld; WARN_ON(tty->driver->type == TTY_DRIVER_TYPE_PTY && tty->driver->subtype == PTY_TYPE_MASTER); /* * Perform the actual termios internal changes under lock. */ /* FIXME: we need to decide on some locking/ordering semantics for the set_termios notification eventually */ down_write(&tty->termios_rwsem); old_termios = tty->termios; tty->termios = *new_termios; unset_locked_termios(tty, &old_termios); if (tty->ops->set_termios) tty->ops->set_termios(tty, &old_termios); else tty_termios_copy_hw(&tty->termios, &old_termios); ld = tty_ldisc_ref(tty); if (ld != NULL) { if (ld->ops->set_termios) ld->ops->set_termios(tty, &old_termios); tty_ldisc_deref(ld); } up_write(&tty->termios_rwsem); return 0; } EXPORT_SYMBOL_GPL(tty_set_termios); /** * set_termios - set termios values for a tty * @tty: terminal device * @arg: user data * @opt: option information * * Helper function to prepare termios data and run necessary other * functions before using tty_set_termios to do the actual changes. * * Locking: * Called functions take ldisc and termios_rwsem locks */ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) { struct ktermios tmp_termios; struct tty_ldisc *ld; int retval = tty_check_change(tty); if (retval) return retval; down_read(&tty->termios_rwsem); tmp_termios = tty->termios; up_read(&tty->termios_rwsem); if (opt & TERMIOS_TERMIO) { if (user_termio_to_kernel_termios(&tmp_termios, (struct termio __user *)arg)) return -EFAULT; #ifdef TCGETS2 } else if (opt & TERMIOS_OLD) { if (user_termios_to_kernel_termios_1(&tmp_termios, (struct termios __user *)arg)) return -EFAULT; } else { if (user_termios_to_kernel_termios(&tmp_termios, (struct termios2 __user *)arg)) return -EFAULT; } #else } else if (user_termios_to_kernel_termios(&tmp_termios, (struct termios __user *)arg)) return -EFAULT; #endif /* If old style Bfoo values are used then load c_ispeed/c_ospeed * with the real speed so its unconditionally usable */ tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios); tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios); ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty); tty_ldisc_deref(ld); } if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) return -ERESTARTSYS; } tty_set_termios(tty, &tmp_termios); /* FIXME: Arguably if tmp_termios == tty->termios AND the actual requested termios was not tmp_termios then we may want to return an error as no user requested change has succeeded */ return 0; } static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) { down_read(&tty->termios_rwsem); *kterm = tty->termios; up_read(&tty->termios_rwsem); } static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) { down_read(&tty->termios_rwsem); *kterm = tty->termios_locked; up_read(&tty->termios_rwsem); } static int get_termio(struct tty_struct *tty, struct termio __user *termio) { struct ktermios kterm; copy_termios(tty, &kterm); if (kernel_termios_to_user_termio(termio, &kterm)) return -EFAULT; return 0; } #ifdef TCGETX /** * set_termiox - set termiox fields if possible * @tty: terminal * @arg: termiox structure from user * @opt: option flags for ioctl type * * Implement the device calling points for the SYS5 termiox ioctl * interface in Linux */ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt) { struct termiox tnew; struct tty_ldisc *ld; if (tty->termiox == NULL) return -EINVAL; if (copy_from_user(&tnew, arg, sizeof(struct termiox))) return -EFAULT; ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty); tty_ldisc_deref(ld); } if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) return -ERESTARTSYS; } down_write(&tty->termios_rwsem); if (tty->ops->set_termiox) tty->ops->set_termiox(tty, &tnew); up_write(&tty->termios_rwsem); return 0; } #endif #ifdef TIOCGETP /* * These are deprecated, but there is limited support.. * * The "sg_flags" translation is a joke.. */ static int get_sgflags(struct tty_struct *tty) { int flags = 0; if (!L_ICANON(tty)) {