// SPDX-License-Identifier: GPL-2.0/* * 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/bits.h>#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 <linux/termios_internal.h>#include "tty.h" #include <asm/io.h>#include <linux/uaccess.h> #undef DEBUG /* * Internal flag options for termios setting behavior */#define TERMIOS_FLUSH BIT(0)#define TERMIOS_WAIT BIT(1)#define TERMIOS_TERMIO BIT(2)#define TERMIOS_OLD BIT(3) /** * tty_chars_in_buffer - characters pending * @tty: terminal * * Returns: 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. */unsigned int tty_chars_in_buffer(struct tty_struct *tty){ if (tty->ops->chars_in_buffer) return tty->ops->chars_in_buffer(tty); return 0;}EXPORT_SYMBOL(tty_chars_in_buffer); /** * tty_write_room - write queue space * @tty: terminal * * Returns: 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. */unsigned 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_unthrottle - flow control * @tty: terminal * * Indicate that a @tty may continue transmitting data down the stack. Takes * the &tty_struct->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 = TTY_FLOW_NO_CHANGE; up_write(&tty->termios_rwsem);}EXPORT_SYMBOL(tty_unthrottle); /** * tty_throttle_safe - flow control * @tty: terminal * * Indicate that a @tty should stop transmitting data down the stack. * tty_throttle_safe() 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: %true if @tty is throttled (or was already throttled) */bool tty_throttle_safe(struct tty_struct *tty){ guard(mutex)(&tty->throttle_mutex); if (tty_throttled(tty)) return true; if (tty->flow_change != TTY_THROTTLE_SAFE) return false; set_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->throttle) tty->ops->throttle(tty); return true;} /** * 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: %true if @tty is unthrottled (or was already unthrottled) */bool tty_unthrottle_safe(struct tty_struct *tty){ guard(mutex)(&tty->throttle_mutex); if (!tty_throttled(tty)) return true; if (tty->flow_change != TTY_UNTHROTTLE_SAFE) return false; clear_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->unthrottle) tty->ops->unthrottle(tty); return true;} /** * 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){ 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, const 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, const 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. * * Returns: %true if change is needed */bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b){ if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) return true; if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) return true; return false;}EXPORT_SYMBOL(tty_termios_hw_change); /** * tty_get_char_size - get size of a character * @cflag: termios cflag value * * Returns: size (in bits) of a character depending on @cflag's %CSIZE setting */unsigned char tty_get_char_size(unsigned int cflag){ switch (cflag & CSIZE) { case CS5: return 5; case CS6: return 6; case CS7: return 7; case CS8: default: return 8; }}EXPORT_SYMBOL_GPL(tty_get_char_size); /** * tty_get_frame_size - get size of a frame * @cflag: termios cflag value * * Get the size (in bits) of a frame depending on @cflag's %CSIZE, %CSTOPB, and * %PARENB setting. The result is a sum of character size, start and stop bits * -- one bit each -- second stop bit (if set), and parity bit (if set). * * Returns: size (in bits) of a frame depending on @cflag's setting. */unsigned char tty_get_frame_size(unsigned int cflag){ unsigned char bits = 2 + tty_get_char_size(cflag); if (cflag & CSTOPB) bits++; if (cflag & PARENB) bits++; if (cflag & ADDRB) bits++; return bits;}EXPORT_SYMBOL_GPL(tty_get_frame_size); /** * tty_set_termios - update termios values * @tty: tty to update * @new_termios: desired new value * * Perform updates to the termios values set on this @tty. A master pty's * termios should never be set. * * Locking: &tty_struct->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); /* Reset any ADDRB changes, ADDRB is changed through ->rs485_config() */ tty->termios.c_cflag ^= (tty->termios.c_cflag ^ old_termios.c_cflag) & ADDRB; 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); /* * Translate a "termio" structure into a "termios". Ugh. */__weak int user_termio_to_kernel_termios(struct ktermios *termios, struct termio __user *termio){ struct termio v; if (copy_from_user(&v, termio, sizeof(struct termio))) return -EFAULT; termios->c_iflag = (0xffff0000 & termios->c_iflag) | v.c_iflag; termios->c_oflag = (0xffff0000 & termios->c_oflag) | v.c_oflag; termios->c_cflag = (0xffff0000 & termios->c_cflag) | v.c_cflag; termios->c_lflag = (0xffff0000 & termios->c_lflag) | v.c_lflag; termios->c_line = (0xffff0000 & termios->c_lflag) | v.c_line; memcpy(termios->c_cc, v.c_cc, NCC); return 0;} /* * Translate a "termios" structure into a "termio". Ugh. */__weak int kernel_termios_to_user_termio(struct termio __user *termio, struct ktermios *termios){ struct termio v; memset(&v, 0, sizeof(struct termio)); v.c_iflag = termios->c_iflag; v.c_oflag = termios->c_oflag; v.c_cflag = termios->c_cflag; v.c_lflag = termios->c_lflag; v.c_line = termios->c_line; memcpy(v.c_cc, termios->c_cc, NCC); return copy_to_user(termio, &v, sizeof(struct termio));} #ifdef TCGETS2__weak int user_termios_to_kernel_termios(struct ktermios *k, struct termios2 __user *u){ return copy_from_user(k, u, sizeof(struct termios2));}__weak int kernel_termios_to_user_termios(struct termios2 __user *u, struct ktermios *k){ return copy_to_user(u, k, sizeof(struct termios2));}__weak int user_termios_to_kernel_termios_1(struct ktermios *k, struct termios __user *u){ return copy_from_user(k, u, sizeof(struct termios));}__weak int kernel_termios_to_user_termios_1(struct termios __user *u, struct ktermios *k){ return copy_to_user(u, k, sizeof(struct termios));} #else __weak int user_termios_to_kernel_termios(struct ktermios *k, struct termios __user *u){ return copy_from_user(k, u, sizeof(struct termios));}__weak int kernel_termios_to_user_termios(struct termios __user *u, struct ktermios *k){ return copy_to_user(u, k, sizeof(struct termios));}#endif /* TCGETS2 */ /** * 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 &tty_struct->ldisc_sem and * &tty_struct->termios_rwsem locks * * Returns: 0 on success, an error otherwise */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); if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) {retry_write_wait: retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty)); if (retval < 0) return retval; if (tty_write_lock(tty, false) < 0) goto retry_write_wait; /* Racing writer? */ if (tty_chars_in_buffer(tty)) { tty_write_unlock(tty); goto retry_write_wait; } ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty);Lines 1–500 of 985. 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// SPDX-License-Identifier: GPL-2.0 /* * 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/bits.h> #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 <linux/termios_internal.h> #include "tty.h" #include <asm/io.h> #include <linux/uaccess.h> #undef DEBUG /* * Internal flag options for termios setting behavior */ #define TERMIOS_FLUSH BIT(0) #define TERMIOS_WAIT BIT(1) #define TERMIOS_TERMIO BIT(2) #define TERMIOS_OLD BIT(3) /** * tty_chars_in_buffer - characters pending * @tty: terminal * * Returns: 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. */ unsigned int tty_chars_in_buffer(struct tty_struct *tty) { if (tty->ops->chars_in_buffer) return tty->ops->chars_in_buffer(tty); return 0; } EXPORT_SYMBOL(tty_chars_in_buffer); /** * tty_write_room - write queue space * @tty: terminal * * Returns: 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. */ unsigned 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_unthrottle - flow control * @tty: terminal * * Indicate that a @tty may continue transmitting data down the stack. Takes * the &tty_struct->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 = TTY_FLOW_NO_CHANGE; up_write(&tty->termios_rwsem); } EXPORT_SYMBOL(tty_unthrottle); /** * tty_throttle_safe - flow control * @tty: terminal * * Indicate that a @tty should stop transmitting data down the stack. * tty_throttle_safe() 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: %true if @tty is throttled (or was already throttled) */ bool tty_throttle_safe(struct tty_struct *tty) { guard(mutex)(&tty->throttle_mutex); if (tty_throttled(tty)) return true; if (tty->flow_change != TTY_THROTTLE_SAFE) return false; set_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->throttle) tty->ops->throttle(tty); return true; } /** * 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: %true if @tty is unthrottled (or was already unthrottled) */ bool tty_unthrottle_safe(struct tty_struct *tty) { guard(mutex)(&tty->throttle_mutex); if (!tty_throttled(tty)) return true; if (tty->flow_change != TTY_UNTHROTTLE_SAFE) return false; clear_bit(TTY_THROTTLED, &tty->flags); if (tty->ops->unthrottle) tty->ops->unthrottle(tty); return true; } /** * 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) { 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, const 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, const 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. * * Returns: %true if change is needed */ bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b) { if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed) return true; if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL)) return true; return false; } EXPORT_SYMBOL(tty_termios_hw_change); /** * tty_get_char_size - get size of a character * @cflag: termios cflag value * * Returns: size (in bits) of a character depending on @cflag's %CSIZE setting */ unsigned char tty_get_char_size(unsigned int cflag) { switch (cflag & CSIZE) { case CS5: return 5; case CS6: return 6; case CS7: return 7; case CS8: default: return 8; } } EXPORT_SYMBOL_GPL(tty_get_char_size); /** * tty_get_frame_size - get size of a frame * @cflag: termios cflag value * * Get the size (in bits) of a frame depending on @cflag's %CSIZE, %CSTOPB, and * %PARENB setting. The result is a sum of character size, start and stop bits * -- one bit each -- second stop bit (if set), and parity bit (if set). * * Returns: size (in bits) of a frame depending on @cflag's setting. */ unsigned char tty_get_frame_size(unsigned int cflag) { unsigned char bits = 2 + tty_get_char_size(cflag); if (cflag & CSTOPB) bits++; if (cflag & PARENB) bits++; if (cflag & ADDRB) bits++; return bits; } EXPORT_SYMBOL_GPL(tty_get_frame_size); /** * tty_set_termios - update termios values * @tty: tty to update * @new_termios: desired new value * * Perform updates to the termios values set on this @tty. A master pty's * termios should never be set. * * Locking: &tty_struct->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); /* Reset any ADDRB changes, ADDRB is changed through ->rs485_config() */ tty->termios.c_cflag ^= (tty->termios.c_cflag ^ old_termios.c_cflag) & ADDRB; 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); /* * Translate a "termio" structure into a "termios". Ugh. */ __weak int user_termio_to_kernel_termios(struct ktermios *termios, struct termio __user *termio) { struct termio v; if (copy_from_user(&v, termio, sizeof(struct termio))) return -EFAULT; termios->c_iflag = (0xffff0000 & termios->c_iflag) | v.c_iflag; termios->c_oflag = (0xffff0000 & termios->c_oflag) | v.c_oflag; termios->c_cflag = (0xffff0000 & termios->c_cflag) | v.c_cflag; termios->c_lflag = (0xffff0000 & termios->c_lflag) | v.c_lflag; termios->c_line = (0xffff0000 & termios->c_lflag) | v.c_line; memcpy(termios->c_cc, v.c_cc, NCC); return 0; } /* * Translate a "termios" structure into a "termio". Ugh. */ __weak int kernel_termios_to_user_termio(struct termio __user *termio, struct ktermios *termios) { struct termio v; memset(&v, 0, sizeof(struct termio)); v.c_iflag = termios->c_iflag; v.c_oflag = termios->c_oflag; v.c_cflag = termios->c_cflag; v.c_lflag = termios->c_lflag; v.c_line = termios->c_line; memcpy(v.c_cc, termios->c_cc, NCC); return copy_to_user(termio, &v, sizeof(struct termio)); } #ifdef TCGETS2 __weak int user_termios_to_kernel_termios(struct ktermios *k, struct termios2 __user *u) { return copy_from_user(k, u, sizeof(struct termios2)); } __weak int kernel_termios_to_user_termios(struct termios2 __user *u, struct ktermios *k) { return copy_to_user(u, k, sizeof(struct termios2)); } __weak int user_termios_to_kernel_termios_1(struct ktermios *k, struct termios __user *u) { return copy_from_user(k, u, sizeof(struct termios)); } __weak int kernel_termios_to_user_termios_1(struct termios __user *u, struct ktermios *k) { return copy_to_user(u, k, sizeof(struct termios)); } #else __weak int user_termios_to_kernel_termios(struct ktermios *k, struct termios __user *u) { return copy_from_user(k, u, sizeof(struct termios)); } __weak int kernel_termios_to_user_termios(struct termios __user *u, struct ktermios *k) { return copy_to_user(u, k, sizeof(struct termios)); } #endif /* TCGETS2 */ /** * 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 &tty_struct->ldisc_sem and * &tty_struct->termios_rwsem locks * * Returns: 0 on success, an error otherwise */ 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); if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) { retry_write_wait: retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty)); if (retval < 0) return retval; if (tty_write_lock(tty, false) < 0) goto retry_write_wait; /* Racing writer? */ if (tty_chars_in_buffer(tty)) { tty_write_unlock(tty); goto retry_write_wait; } ld = tty_ldisc_ref(tty); if (ld != NULL) { if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer) ld->ops->flush_buffer(tty);