diff options
Diffstat (limited to 'drivers/tty/tty_ioctl.c')
| -rw-r--r-- | drivers/tty/tty_ioctl.c | 378 |
1 files changed, 214 insertions, 164 deletions
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index 0c188997145..6fd60fece6b 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -1,6 +1,4 @@ /* - * linux/drivers/char/tty_ioctl.c - * * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds * * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines @@ -21,10 +19,10 @@ #include <linux/module.h> #include <linux/bitops.h> #include <linux/mutex.h> +#include <linux/compat.h> #include <asm/io.h> #include <asm/uaccess.h> -#include <asm/system.h> #undef TTY_DEBUG_WAIT_UNTIL_SENT @@ -96,19 +94,20 @@ EXPORT_SYMBOL(tty_driver_flush_buffer); * @tty: terminal * * Indicate that a tty should stop transmitting data down the stack. - * Takes the termios mutex to protect against parallel throttle/unthrottle + * 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) { - mutex_lock(&tty->termios_mutex); + 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); - mutex_unlock(&tty->termios_mutex); + tty->flow_change = 0; + up_write(&tty->termios_rwsem); } EXPORT_SYMBOL(tty_throttle); @@ -117,7 +116,7 @@ EXPORT_SYMBOL(tty_throttle); * @tty: terminal * * Indicate that a tty may continue transmitting data down the stack. - * Takes the termios mutex to protect against parallel throttle/unthrottle + * 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. * @@ -127,15 +126,78 @@ EXPORT_SYMBOL(tty_throttle); void tty_unthrottle(struct tty_struct *tty) { - mutex_lock(&tty->termios_mutex); + down_write(&tty->termios_rwsem); if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && tty->ops->unthrottle) tty->ops->unthrottle(tty); - mutex_unlock(&tty->termios_mutex); + 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 (!test_bit(TTY_THROTTLED, &tty->flags)) { + 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 (test_bit(TTY_THROTTLED, &tty->flags)) { + 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 @@ -247,7 +309,7 @@ speed_t tty_termios_baud_rate(struct ktermios *termios) cbaud = termios->c_cflag & CBAUD; #ifdef BOTHER - /* Magic token for arbitary speed via c_ispeed/c_ospeed */ + /* Magic token for arbitrary speed via c_ispeed/c_ospeed */ if (cbaud == BOTHER) return termios->c_ospeed; #endif @@ -283,7 +345,7 @@ speed_t tty_termios_input_baud_rate(struct ktermios *termios) if (cbaud == B0) return tty_termios_baud_rate(termios); - /* Magic token for arbitary speed via c_ispeed*/ + /* Magic token for arbitrary speed via c_ispeed*/ if (cbaud == BOTHER) return termios->c_ispeed; @@ -309,7 +371,7 @@ EXPORT_SYMBOL(tty_termios_input_baud_rate); * @ospeed: output speed * * Encode the speeds set into the passed termios structure. This is - * used as a library helper for drivers os that they can report back + * used as a library helper for drivers so that they can report back * the actual speed selected when it differs from the speed requested * * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour @@ -406,50 +468,22 @@ EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate); * @obad: output baud rate * * Update the current termios data for the tty with the new speed - * settings. The caller must hold the termios_mutex for the tty in + * settings. The caller must hold the termios_rwsem for the tty in * question. */ void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud) { - tty_termios_encode_baud_rate(tty->termios, ibaud, obaud); + tty_termios_encode_baud_rate(&tty->termios, ibaud, obaud); } EXPORT_SYMBOL_GPL(tty_encode_baud_rate); /** - * tty_get_baud_rate - get tty bit rates - * @tty: tty to query - * - * Returns the baud rate as an integer for this terminal. The - * termios lock must be held by the caller and the terminal bit - * flags may be updated. - * - * Locking: none - */ - -speed_t tty_get_baud_rate(struct tty_struct *tty) -{ - speed_t baud = tty_termios_baud_rate(tty->termios); - - if (baud == 38400 && tty->alt_speed) { - if (!tty->warned) { - printk(KERN_WARNING "Use of setserial/setrocket to " - "set SPD_* flags is deprecated\n"); - tty->warned = 1; - } - baud = tty->alt_speed; - } - - return baud; -} -EXPORT_SYMBOL(tty_get_baud_rate); - -/** * tty_termios_copy_hw - copy hardware settings * @new: New termios * @old: Old termios * - * Propogate the hardware specific terminal setting bits from + * 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 @@ -486,7 +520,7 @@ int tty_termios_hw_change(struct ktermios *a, struct ktermios *b) EXPORT_SYMBOL(tty_termios_hw_change); /** - * change_termios - update termios values + * tty_set_termios - update termios values * @tty: tty to update * @new_termios: desired new value * @@ -494,10 +528,10 @@ EXPORT_SYMBOL(tty_termios_hw_change); * is a bit of layering violation here with n_tty in terms of the * internal knowledge of this function. * - * Locking: termios_mutex + * Locking: termios_rwsem */ -static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) +int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios) { struct ktermios old_termios; struct tty_ldisc *ld; @@ -510,15 +544,15 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) /* FIXME: we need to decide on some locking/ordering semantics for the set_termios notification eventually */ - mutex_lock(&tty->termios_mutex); - old_termios = *tty->termios; - *tty->termios = *new_termios; - unset_locked_termios(tty->termios, &old_termios, tty->termios_locked); + down_write(&tty->termios_rwsem); + old_termios = tty->termios; + tty->termios = *new_termios; + unset_locked_termios(&tty->termios, &old_termios, &tty->termios_locked); /* See if packet mode change of state. */ if (tty->link && tty->link->packet) { int extproc = (old_termios.c_lflag & EXTPROC) | - (tty->termios->c_lflag & EXTPROC); + (tty->termios.c_lflag & EXTPROC); int old_flow = ((old_termios.c_iflag & IXON) && (old_termios.c_cc[VSTOP] == '\023') && (old_termios.c_cc[VSTART] == '\021')); @@ -544,7 +578,7 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) if (tty->ops->set_termios) (*tty->ops->set_termios)(tty, &old_termios); else - tty_termios_copy_hw(tty->termios, &old_termios); + tty_termios_copy_hw(&tty->termios, &old_termios); ld = tty_ldisc_ref(tty); if (ld != NULL) { @@ -552,8 +586,10 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) (ld->ops->set_termios)(tty, &old_termios); tty_ldisc_deref(ld); } - mutex_unlock(&tty->termios_mutex); + up_write(&tty->termios_rwsem); + return 0; } +EXPORT_SYMBOL_GPL(tty_set_termios); /** * set_termios - set termios values for a tty @@ -562,10 +598,10 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) * @opt: option information * * Helper function to prepare termios data and run necessary other - * functions before using change_termios to do the actual changes. + * functions before using tty_set_termios to do the actual changes. * * Locking: - * Called functions take ldisc and termios_mutex locks + * Called functions take ldisc and termios_rwsem locks */ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) @@ -577,9 +613,9 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) if (retval) return retval; - mutex_lock(&tty->termios_mutex); - memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); + 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, @@ -617,10 +653,10 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) - return -EINTR; + return -ERESTARTSYS; } - change_termios(tty, &tmp_termios); + 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 @@ -631,16 +667,16 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) { - mutex_lock(&tty->termios_mutex); - memcpy(kterm, tty->termios, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); + 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) { - mutex_lock(&tty->termios_mutex); - memcpy(kterm, tty->termios_locked, sizeof(struct ktermios)); - mutex_unlock(&tty->termios_mutex); + 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) @@ -684,13 +720,13 @@ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt) if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) - return -EINTR; + return -ERESTARTSYS; } - mutex_lock(&tty->termios_mutex); + down_write(&tty->termios_rwsem); if (tty->ops->set_termiox) tty->ops->set_termiox(tty, &tnew); - mutex_unlock(&tty->termios_mutex); + up_write(&tty->termios_rwsem); return 0; } @@ -707,16 +743,16 @@ static int get_sgflags(struct tty_struct *tty) { int flags = 0; - if (!(tty->termios->c_lflag & ICANON)) { - if (tty->termios->c_lflag & ISIG) + if (!(tty->termios.c_lflag & ICANON)) { + if (tty->termios.c_lflag & ISIG) flags |= 0x02; /* cbreak */ else flags |= 0x20; /* raw */ } - if (tty->termios->c_lflag & ECHO) + if (tty->termios.c_lflag & ECHO) flags |= 0x08; /* echo */ - if (tty->termios->c_oflag & OPOST) - if (tty->termios->c_oflag & ONLCR) + if (tty->termios.c_oflag & OPOST) + if (tty->termios.c_oflag & ONLCR) flags |= 0x10; /* crmod */ return flags; } @@ -725,13 +761,13 @@ static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) { struct sgttyb tmp; - mutex_lock(&tty->termios_mutex); - tmp.sg_ispeed = tty->termios->c_ispeed; - tmp.sg_ospeed = tty->termios->c_ospeed; - tmp.sg_erase = tty->termios->c_cc[VERASE]; - tmp.sg_kill = tty->termios->c_cc[VKILL]; + down_read(&tty->termios_rwsem); + tmp.sg_ispeed = tty->termios.c_ispeed; + tmp.sg_ospeed = tty->termios.c_ospeed; + tmp.sg_erase = tty->termios.c_cc[VERASE]; + tmp.sg_kill = tty->termios.c_cc[VKILL]; tmp.sg_flags = get_sgflags(tty); - mutex_unlock(&tty->termios_mutex); + up_read(&tty->termios_rwsem); return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; } @@ -770,7 +806,7 @@ static void set_sgflags(struct ktermios *termios, int flags) * Updates a terminal from the legacy BSD style terminal information * structure. * - * Locking: termios_mutex + * Locking: termios_rwsem */ static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) @@ -786,8 +822,8 @@ static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) return -EFAULT; - mutex_lock(&tty->termios_mutex); - termios = *tty->termios; + down_write(&tty->termios_rwsem); + termios = tty->termios; termios.c_cc[VERASE] = tmp.sg_erase; termios.c_cc[VKILL] = tmp.sg_kill; set_sgflags(&termios, tmp.sg_flags); @@ -796,8 +832,8 @@ static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb) tty_termios_encode_baud_rate(&termios, termios.c_ispeed, termios.c_ospeed); #endif - mutex_unlock(&tty->termios_mutex); - change_termios(tty, &termios); + up_write(&tty->termios_rwsem); + tty_set_termios(tty, &termios); return 0; } #endif @@ -807,14 +843,14 @@ static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) { struct tchars tmp; - mutex_lock(&tty->termios_mutex); - tmp.t_intrc = tty->termios->c_cc[VINTR]; - tmp.t_quitc = tty->termios->c_cc[VQUIT]; - tmp.t_startc = tty->termios->c_cc[VSTART]; - tmp.t_stopc = tty->termios->c_cc[VSTOP]; - tmp.t_eofc = tty->termios->c_cc[VEOF]; - tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */ - mutex_unlock(&tty->termios_mutex); + down_read(&tty->termios_rwsem); + tmp.t_intrc = tty->termios.c_cc[VINTR]; + tmp.t_quitc = tty->termios.c_cc[VQUIT]; + tmp.t_startc = tty->termios.c_cc[VSTART]; + tmp.t_stopc = tty->termios.c_cc[VSTOP]; + 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; } @@ -824,14 +860,14 @@ static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) if (copy_from_user(&tmp, tchars, sizeof(tmp))) return -EFAULT; - mutex_lock(&tty->termios_mutex); - 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? */ - mutex_unlock(&tty->termios_mutex); + 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 @@ -841,16 +877,16 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) { struct ltchars tmp; - mutex_lock(&tty->termios_mutex); - tmp.t_suspc = tty->termios->c_cc[VSUSP]; + 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]; + 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]; - mutex_unlock(&tty->termios_mutex); + 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; } @@ -861,16 +897,16 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) if (copy_from_user(&tmp, ltchars, sizeof(tmp))) return -EFAULT; - mutex_lock(&tty->termios_mutex); - tty->termios->c_cc[VSUSP] = tmp.t_suspc; + 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; + 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; - mutex_unlock(&tty->termios_mutex); + 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 @@ -910,7 +946,7 @@ static int send_prio_char(struct tty_struct *tty, char ch) * @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 mutex + * layer to make it visible. All done with the termios rwsem */ static int tty_change_softcar(struct tty_struct *tty, int arg) @@ -919,15 +955,15 @@ static int tty_change_softcar(struct tty_struct *tty, int arg) int bit = arg ? CLOCAL : 0; struct ktermios old; - mutex_lock(&tty->termios_mutex); - old = *tty->termios; - tty->termios->c_cflag &= ~CLOCAL; - tty->termios->c_cflag |= bit; + 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 ((tty->termios->c_cflag & CLOCAL) != bit) + if ((tty->termios.c_cflag & CLOCAL) != bit) ret = -EINVAL; - mutex_unlock(&tty->termios_mutex); + up_write(&tty->termios_rwsem); return ret; } @@ -951,6 +987,8 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 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; @@ -1028,9 +1066,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, if (user_termios_to_kernel_termios(&kterm, (struct termios __user *) arg)) return -EFAULT; - mutex_lock(&real_tty->termios_mutex); - memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); - mutex_unlock(&real_tty->termios_mutex); + down_write(&real_tty->termios_rwsem); + real_tty->termios_locked = kterm; + up_write(&real_tty->termios_rwsem); return 0; #else case TIOCGLCKTRMIOS: @@ -1045,9 +1083,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, if (user_termios_to_kernel_termios_1(&kterm, (struct termios __user *) arg)) return -EFAULT; - mutex_lock(&real_tty->termios_mutex); - memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); - mutex_unlock(&real_tty->termios_mutex); + down_write(&real_tty->termios_rwsem); + real_tty->termios_locked = kterm; + up_write(&real_tty->termios_rwsem); return ret; #endif #ifdef TCGETX @@ -1055,9 +1093,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, struct termiox ktermx; if (real_tty->termiox == NULL) return -EINVAL; - mutex_lock(&real_tty->termios_mutex); + down_read(&real_tty->termios_rwsem); memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox)); - mutex_unlock(&real_tty->termios_mutex); + up_read(&real_tty->termios_rwsem); if (copy_to_user(p, &ktermx, sizeof(struct termiox))) ret = -EFAULT; return ret; @@ -1084,39 +1122,52 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, } EXPORT_SYMBOL_GPL(tty_mode_ioctl); -int tty_perform_flush(struct tty_struct *tty, unsigned long arg) + +/* Caller guarantees ldisc reference is held */ +static 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; + struct tty_ldisc *ld = tty->ldisc; - ld = tty_ldisc_ref_wait(tty); switch (arg) { case TCIFLUSH: - if (ld && ld->ops->flush_buffer) + if (ld && ld->ops->flush_buffer) { ld->ops->flush_buffer(tty); + tty_unthrottle(tty); + } break; case TCIOFLUSH: - if (ld && ld->ops->flush_buffer) + if (ld && ld->ops->flush_buffer) { ld->ops->flush_buffer(tty); + tty_unthrottle(tty); + } /* fall through */ case TCOFLUSH: tty_driver_flush_buffer(tty); break; default: - tty_ldisc_deref(ld); return -EINVAL; } - tty_ldisc_deref(ld); 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) { - unsigned long flags; int retval; switch (cmd) { @@ -1150,30 +1201,29 @@ int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, } return 0; case TCFLSH: - return tty_perform_flush(tty, arg); - case TIOCPKT: - { - int pktmode; - - if (tty->driver->type != TTY_DRIVER_TYPE_PTY || - tty->driver->subtype != PTY_TYPE_MASTER) - return -ENOTTY; - if (get_user(pktmode, (int __user *) arg)) - return -EFAULT; - spin_lock_irqsave(&tty->ctrl_lock, flags); - if (pktmode) { - if (!tty->packet) { - tty->packet = 1; - tty->link->ctrl_status = 0; - } - } else - tty->packet = 0; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - return 0; - } + 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); + +#ifdef CONFIG_COMPAT +long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, + unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case TIOCGLCKTRMIOS: + case TIOCSLCKTRMIOS: + return tty_mode_ioctl(tty, file, cmd, (unsigned long) compat_ptr(arg)); + default: + return -ENOIOCTLCMD; + } +} +EXPORT_SYMBOL(n_tty_compat_ioctl_helper); +#endif + |