diff options
Diffstat (limited to 'drivers/tty/tty_io.c')
| -rw-r--r-- | drivers/tty/tty_io.c | 440 |
1 files changed, 223 insertions, 217 deletions
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 0508a1d8e4cd..4f35b43e2475 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -153,8 +153,6 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd, static int __tty_fasync(int fd, struct file *filp, int on); static int tty_fasync(int fd, struct file *filp, int on); static void release_tty(struct tty_struct *tty, int idx); -static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); -static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty); /** * free_tty_struct - free a disused tty @@ -169,8 +167,7 @@ void free_tty_struct(struct tty_struct *tty) { if (!tty) return; - if (tty->dev) - put_device(tty->dev); + put_device(tty->dev); kfree(tty->write_buf); tty->magic = 0xDEADDEAD; kfree(tty); @@ -277,6 +274,7 @@ int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, return 0; } +/* Caller must hold tty_lock */ static int check_tty_count(struct tty_struct *tty, const char *routine) { #ifdef CHECK_TTY_COUNT @@ -492,6 +490,78 @@ static const struct file_operations hung_up_tty_fops = { static DEFINE_SPINLOCK(redirect_lock); static struct file *redirect; + +void proc_clear_tty(struct task_struct *p) +{ + unsigned long flags; + struct tty_struct *tty; + spin_lock_irqsave(&p->sighand->siglock, flags); + tty = p->signal->tty; + p->signal->tty = NULL; + spin_unlock_irqrestore(&p->sighand->siglock, flags); + tty_kref_put(tty); +} + +/** + * proc_set_tty - set the controlling terminal + * + * Only callable by the session leader and only if it does not already have + * a controlling terminal. + * + * Caller must hold: tty_lock() + * a readlock on tasklist_lock + * sighand lock + */ +static void __proc_set_tty(struct tty_struct *tty) +{ + unsigned long flags; + + spin_lock_irqsave(&tty->ctrl_lock, flags); + /* + * The session and fg pgrp references will be non-NULL if + * tiocsctty() is stealing the controlling tty + */ + put_pid(tty->session); + put_pid(tty->pgrp); + tty->pgrp = get_pid(task_pgrp(current)); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + tty->session = get_pid(task_session(current)); + if (current->signal->tty) { + printk(KERN_DEBUG "tty not NULL!!\n"); + tty_kref_put(current->signal->tty); + } + put_pid(current->signal->tty_old_pgrp); + current->signal->tty = tty_kref_get(tty); + current->signal->tty_old_pgrp = NULL; +} + +static void proc_set_tty(struct tty_struct *tty) +{ + spin_lock_irq(¤t->sighand->siglock); + __proc_set_tty(tty); + spin_unlock_irq(¤t->sighand->siglock); +} + +struct tty_struct *get_current_tty(void) +{ + struct tty_struct *tty; + unsigned long flags; + + spin_lock_irqsave(¤t->sighand->siglock, flags); + tty = tty_kref_get(current->signal->tty); + spin_unlock_irqrestore(¤t->sighand->siglock, flags); + return tty; +} +EXPORT_SYMBOL_GPL(get_current_tty); + +static void session_clear_tty(struct pid *session) +{ + struct task_struct *p; + do_each_pid_task(session, PIDTYPE_SID, p) { + proc_clear_tty(p); + } while_each_pid_task(session, PIDTYPE_SID, p); +} + /** * tty_wakeup - request more data * @tty: terminal @@ -620,9 +690,6 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session) return; } - /* some functions below drop BTM, so we need this bit */ - set_bit(TTY_HUPPING, &tty->flags); - /* inuse_filps is protected by the single tty lock, this really needs to change if we want to flush the workqueue with the lock held */ @@ -647,10 +714,6 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session) while (refs--) tty_kref_put(tty); - /* - * it drops BTM and thus races with reopen - * we protect the race by TTY_HUPPING - */ tty_ldisc_hangup(tty); spin_lock_irq(&tty->ctrl_lock); @@ -682,8 +745,6 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session) * can't yet guarantee all that. */ set_bit(TTY_HUPPED, &tty->flags); - clear_bit(TTY_HUPPING, &tty->flags); - tty_unlock(tty); if (f) @@ -792,14 +853,6 @@ int tty_hung_up_p(struct file *filp) EXPORT_SYMBOL(tty_hung_up_p); -static void session_clear_tty(struct pid *session) -{ - struct task_struct *p; - do_each_pid_task(session, PIDTYPE_SID, p) { - proc_clear_tty(p); - } while_each_pid_task(session, PIDTYPE_SID, p); -} - /** * disassociate_ctty - disconnect controlling tty * @on_exit: true if exiting so need to "hang up" the session @@ -927,7 +980,7 @@ void __stop_tty(struct tty_struct *tty) return; tty->stopped = 1; if (tty->ops->stop) - (tty->ops->stop)(tty); + tty->ops->stop(tty); } void stop_tty(struct tty_struct *tty) @@ -958,7 +1011,7 @@ void __start_tty(struct tty_struct *tty) return; tty->stopped = 0; if (tty->ops->start) - (tty->ops->start)(tty); + tty->ops->start(tty); tty_wakeup(tty); } @@ -1012,7 +1065,7 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count, situation */ ld = tty_ldisc_ref_wait(tty); if (ld->ops->read) - i = (ld->ops->read)(tty, file, buf, count); + i = ld->ops->read(tty, file, buf, count); else i = -EIO; tty_ldisc_deref(ld); @@ -1024,14 +1077,12 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count, } static void tty_write_unlock(struct tty_struct *tty) - __releases(&tty->atomic_write_lock) { mutex_unlock(&tty->atomic_write_lock); wake_up_interruptible_poll(&tty->write_wait, POLLOUT); } static int tty_write_lock(struct tty_struct *tty, int ndelay) - __acquires(&tty->atomic_write_lock) { if (!mutex_trylock(&tty->atomic_write_lock)) { if (ndelay) @@ -1146,7 +1197,7 @@ void tty_write_message(struct tty_struct *tty, char *msg) if (tty) { mutex_lock(&tty->atomic_write_lock); tty_lock(tty); - if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) { + if (tty->ops->write && tty->count > 0) { tty_unlock(tty); tty->ops->write(tty, msg, strlen(msg)); } else @@ -1293,19 +1344,24 @@ static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p) * @driver: the driver for the tty * @idx: the minor number * - * Return the tty, if found or ERR_PTR() otherwise. + * Return the tty, if found. If not found, return NULL or ERR_PTR() if the + * driver lookup() method returns an error. * - * Locking: tty_mutex must be held. If tty is found, the mutex must - * be held until the 'fast-open' is also done. Will change once we - * have refcounting in the driver and per driver locking + * Locking: tty_mutex must be held. If the tty is found, bump the tty kref. */ static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, struct inode *inode, int idx) { + struct tty_struct *tty; + if (driver->ops->lookup) - return driver->ops->lookup(driver, inode, idx); + tty = driver->ops->lookup(driver, inode, idx); + else + tty = driver->ttys[idx]; - return driver->ttys[idx]; + if (!IS_ERR(tty)) + tty_kref_get(tty); + return tty; } /** @@ -1393,29 +1449,21 @@ void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty) * @tty - the tty to open * * Return 0 on success, -errno on error. + * Re-opens on master ptys are not allowed and return -EIO. * - * Locking: tty_mutex must be held from the time the tty was found - * till this open completes. + * Locking: Caller must hold tty_lock */ static int tty_reopen(struct tty_struct *tty) { struct tty_driver *driver = tty->driver; - if (test_bit(TTY_CLOSING, &tty->flags) || - test_bit(TTY_HUPPING, &tty->flags)) + if (!tty->count) return -EIO; if (driver->type == TTY_DRIVER_TYPE_PTY && - driver->subtype == PTY_TYPE_MASTER) { - /* - * special case for PTY masters: only one open permitted, - * and the slave side open count is incremented as well. - */ - if (tty->count) - return -EIO; + driver->subtype == PTY_TYPE_MASTER) + return -EIO; - tty->link->count++; - } tty->count++; WARN_ON(!tty->ldisc); @@ -1535,15 +1583,19 @@ void tty_free_termios(struct tty_struct *tty) EXPORT_SYMBOL(tty_free_termios); /** - * tty_flush_works - flush all works of a tty - * @tty: tty device to flush works for + * tty_flush_works - flush all works of a tty/pty pair + * @tty: tty device to flush works for (or either end of a pty pair) * - * Sync flush all works belonging to @tty. + * Sync flush all works belonging to @tty (and the 'other' tty). */ static void tty_flush_works(struct tty_struct *tty) { flush_work(&tty->SAK_work); flush_work(&tty->hangup_work); + if (tty->link) { + flush_work(&tty->link->SAK_work); + flush_work(&tty->link->hangup_work); + } } /** @@ -1635,8 +1687,7 @@ static void release_tty(struct tty_struct *tty, int idx) tty->link->port->itty = NULL; cancel_work_sync(&tty->port->buf.work); - if (tty->link) - tty_kref_put(tty->link); + tty_kref_put(tty->link); tty_kref_put(tty); } @@ -1649,8 +1700,7 @@ static void release_tty(struct tty_struct *tty, int idx) * Performs some paranoid checking before true release of the @tty. * This is a no-op unless TTY_PARANOIA_CHECK is defined. */ -static int tty_release_checks(struct tty_struct *tty, struct tty_struct *o_tty, - int idx) +static int tty_release_checks(struct tty_struct *tty, int idx) { #ifdef TTY_PARANOIA_CHECK if (idx < 0 || idx >= tty->driver->num) { @@ -1669,6 +1719,8 @@ static int tty_release_checks(struct tty_struct *tty, struct tty_struct *o_tty, return -1; } if (tty->driver->other) { + struct tty_struct *o_tty = tty->link; + if (o_tty != tty->driver->other->ttys[idx]) { printk(KERN_DEBUG "%s: other->table[%d] not o_tty for (%s)\n", __func__, idx, tty->name); @@ -1705,8 +1757,8 @@ static int tty_release_checks(struct tty_struct *tty, struct tty_struct *o_tty, int tty_release(struct inode *inode, struct file *filp) { struct tty_struct *tty = file_tty(filp); - struct tty_struct *o_tty; - int pty_master, tty_closing, o_tty_closing, do_sleep; + struct tty_struct *o_tty = NULL; + int do_sleep, final; int idx; char buf[64]; long timeout = 0; @@ -1721,12 +1773,11 @@ int tty_release(struct inode *inode, struct file *filp) __tty_fasync(-1, filp, 0); idx = tty->index; - pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER); - /* Review: parallel close */ - o_tty = tty->link; + if (tty->driver->type == TTY_DRIVER_TYPE_PTY && + tty->driver->subtype == PTY_TYPE_MASTER) + o_tty = tty->link; - if (tty_release_checks(tty, o_tty, idx)) { + if (tty_release_checks(tty, idx)) { tty_unlock(tty); return 0; } @@ -1739,7 +1790,9 @@ int tty_release(struct inode *inode, struct file *filp) if (tty->ops->close) tty->ops->close(tty, filp); - tty_unlock(tty); + /* If tty is pty master, lock the slave pty (stable lock order) */ + tty_lock_slave(o_tty); + /* * Sanity check: if tty->count is going to zero, there shouldn't be * any waiters on tty->read_wait or tty->write_wait. We test the @@ -1750,25 +1803,13 @@ int tty_release(struct inode *inode, struct file *filp) * The test for the o_tty closing is necessary, since the master and * slave sides may close in any order. If the slave side closes out * first, its count will be one, since the master side holds an open. - * Thus this test wouldn't be triggered at the time the slave closes, + * Thus this test wouldn't be triggered at the time the slave closed, * so we do it now. - * - * Note that it's possible for the tty to be opened again while we're - * flushing out waiters. By recalculating the closing flags before - * each iteration we avoid any problems. */ while (1) { - /* Guard against races with tty->count changes elsewhere and - opens on /dev/tty */ - - mutex_lock(&tty_mutex); - tty_lock_pair(tty, o_tty); - tty_closing = tty->count <= 1; - o_tty_closing = o_tty && - (o_tty->count <= (pty_master ? 1 : 0)); do_sleep = 0; - if (tty_closing) { + if (tty->count <= 1) { if (waitqueue_active(&tty->read_wait)) { wake_up_poll(&tty->read_wait, POLLIN); do_sleep++; @@ -1778,7 +1819,7 @@ int tty_release(struct inode *inode, struct file *filp) do_sleep++; } } - if (o_tty_closing) { + if (o_tty && o_tty->count <= 1) { if (waitqueue_active(&o_tty->read_wait)) { wake_up_poll(&o_tty->read_wait, POLLIN); do_sleep++; @@ -1796,8 +1837,6 @@ int tty_release(struct inode *inode, struct file *filp) printk(KERN_WARNING "%s: %s: read/write wait queue active!\n", __func__, tty_name(tty, buf)); } - tty_unlock_pair(tty, o_tty); - mutex_unlock(&tty_mutex); schedule_timeout_killable(timeout); if (timeout < 120 * HZ) timeout = 2 * timeout + 1; @@ -1805,15 +1844,7 @@ int tty_release(struct inode *inode, struct file *filp) timeout = MAX_SCHEDULE_TIMEOUT; } - /* - * The closing flags are now consistent with the open counts on - * both sides, and we've completed the last operation that could - * block, so it's safe to proceed with closing. - * - * We must *not* drop the tty_mutex until we ensure that a further - * entry into tty_open can not pick up this tty. - */ - if (pty_master) { + if (o_tty) { if (--o_tty->count < 0) { printk(KERN_WARNING "%s: bad pty slave count (%d) for %s\n", __func__, o_tty->count, tty_name(o_tty, buf)); @@ -1840,21 +1871,11 @@ int tty_release(struct inode *inode, struct file *filp) /* * Perform some housekeeping before deciding whether to return. * - * Set the TTY_CLOSING flag if this was the last open. In the - * case of a pty we may have to wait around for the other side - * to close, and TTY_CLOSING makes sure we can't be reopened. - */ - if (tty_closing) - set_bit(TTY_CLOSING, &tty->flags); - if (o_tty_closing) - set_bit(TTY_CLOSING, &o_tty->flags); - - /* * If _either_ side is closing, make sure there aren't any * processes that still think tty or o_tty is their controlling * tty. */ - if (tty_closing || o_tty_closing) { + if (!tty->count) { read_lock(&tasklist_lock); session_clear_tty(tty->session); if (o_tty) @@ -1862,13 +1883,16 @@ int tty_release(struct inode *inode, struct file *filp) read_unlock(&tasklist_lock); } - mutex_unlock(&tty_mutex); - tty_unlock_pair(tty, o_tty); - /* At this point the TTY_CLOSING flag should ensure a dead tty + /* check whether both sides are closing ... */ + final = !tty->count && !(o_tty && o_tty->count); + + tty_unlock_slave(o_tty); + tty_unlock(tty); + + /* At this point, the tty->count == 0 should ensure a dead tty cannot be re-opened by a racing opener */ - /* check whether both sides are closing ... */ - if (!tty_closing || (o_tty && !o_tty_closing)) + if (!final) return 0; #ifdef TTY_DEBUG_HANGUP @@ -1877,12 +1901,10 @@ int tty_release(struct inode *inode, struct file *filp) /* * Ask the line discipline code to release its structures */ - tty_ldisc_release(tty, o_tty); + tty_ldisc_release(tty); /* Wait for pending work before tty destruction commmences */ tty_flush_works(tty); - if (o_tty) - tty_flush_works(o_tty); #ifdef TTY_DEBUG_HANGUP printk(KERN_DEBUG "%s: %s: freeing structure...\n", __func__, tty_name(tty, buf)); @@ -1901,20 +1923,20 @@ int tty_release(struct inode *inode, struct file *filp) } /** - * tty_open_current_tty - get tty of current task for open + * tty_open_current_tty - get locked tty of current task * @device: device number * @filp: file pointer to tty - * @return: tty of the current task iff @device is /dev/tty + * @return: locked tty of the current task iff @device is /dev/tty + * + * Performs a re-open of the current task's controlling tty. * * We cannot return driver and index like for the other nodes because * devpts will not work then. It expects inodes to be from devpts FS. - * - * We need to move to returning a refcounted object from all the lookup - * paths including this one. */ static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) { struct tty_struct *tty; + int retval; if (device != MKDEV(TTYAUX_MAJOR, 0)) return NULL; @@ -1925,9 +1947,14 @@ static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp) filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */ /* noctty = 1; */ - tty_kref_put(tty); - /* FIXME: we put a reference and return a TTY! */ - /* This is only safe because the caller holds tty_mutex */ + tty_lock(tty); + tty_kref_put(tty); /* safe to drop the kref now */ + + retval = tty_reopen(tty); + if (retval < 0) { + tty_unlock(tty); + tty = ERR_PTR(retval); + } return tty; } @@ -2025,13 +2052,9 @@ retry_open: index = -1; retval = 0; - mutex_lock(&tty_mutex); - /* This is protected by the tty_mutex */ tty = tty_open_current_tty(device, filp); - if (IS_ERR(tty)) { - retval = PTR_ERR(tty); - goto err_unlock; - } else if (!tty) { + if (!tty) { + mutex_lock(&tty_mutex); driver = tty_lookup_driver(device, filp, &noctty, &index); if (IS_ERR(driver)) { retval = PTR_ERR(driver); @@ -2044,21 +2067,25 @@ retry_open: retval = PTR_ERR(tty); goto err_unlock; } - } - if (tty) { - tty_lock(tty); - retval = tty_reopen(tty); - if (retval < 0) { - tty_unlock(tty); - tty = ERR_PTR(retval); + if (tty) { + mutex_unlock(&tty_mutex); + tty_lock(tty); + /* safe to drop the kref from tty_driver_lookup_tty() */ + tty_kref_put(tty); + retval = tty_reopen(tty); + if (retval < 0) { + tty_unlock(tty); + tty = ERR_PTR(retval); + } + } else { /* Returns with the tty_lock held for now */ + tty = tty_init_dev(driver, index); + mutex_unlock(&tty_mutex); } - } else /* Returns with the tty_lock held for now */ - tty = tty_init_dev(driver, index); - mutex_unlock(&tty_mutex); - if (driver) tty_driver_kref_put(driver); + } + if (IS_ERR(tty)) { retval = PTR_ERR(tty); goto err_file; @@ -2100,25 +2127,23 @@ retry_open: /* * Need to reset f_op in case a hangup happened. */ - if (filp->f_op == &hung_up_tty_fops) + if (tty_hung_up_p(filp)) filp->f_op = &tty_fops; goto retry_open; } clear_bit(TTY_HUPPED, &tty->flags); - tty_unlock(tty); - mutex_lock(&tty_mutex); - tty_lock(tty); + read_lock(&tasklist_lock); spin_lock_irq(¤t->sighand->siglock); if (!noctty && current->signal->leader && !current->signal->tty && tty->session == NULL) - __proc_set_tty(current, tty); + __proc_set_tty(tty); spin_unlock_irq(¤t->sighand->siglock); + read_unlock(&tasklist_lock); tty_unlock(tty); - mutex_unlock(&tty_mutex); return 0; err_unlock: mutex_unlock(&tty_mutex); @@ -2155,7 +2180,7 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait) ld = tty_ldisc_ref_wait(tty); if (ld->ops->poll) - ret = (ld->ops->poll)(tty, filp, wait); + ret = ld->ops->poll(tty, filp, wait); tty_ldisc_deref(ld); return ret; } @@ -2283,18 +2308,14 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) int tty_do_resize(struct tty_struct *tty, struct winsize *ws) { struct pid *pgrp; - unsigned long flags; /* Lock the tty */ mutex_lock(&tty->winsize_mutex); if (!memcmp(ws, &tty->winsize, sizeof(*ws))) goto done; - /* Get the PID values and reference them so we can - avoid holding the tty ctrl lock while sending signals */ - spin_lock_irqsave(&tty->ctrl_lock, flags); - pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); + /* Signal the foreground process group */ + pgrp = tty_get_pgrp(tty); if (pgrp) kill_pgrp(pgrp, SIGWINCH, 1); put_pid(pgrp); @@ -2403,7 +2424,7 @@ static int fionbio(struct file *file, int __user *p) * leader to set this tty as the controlling tty for the session. * * Locking: - * Takes tty_mutex() to protect tty instance + * Takes tty_lock() to serialize proc_set_tty() for this tty * Takes tasklist_lock internally to walk sessions * Takes ->siglock() when updating signal->tty */ @@ -2411,10 +2432,13 @@ static int fionbio(struct file *file, int __user *p) static int tiocsctty(struct tty_struct *tty, int arg) { int ret = 0; + + tty_lock(tty); + read_lock(&tasklist_lock); + if (current->signal->leader && (task_session(current) == tty->session)) - return ret; + goto unlock; - mutex_lock(&tty_mutex); /* * The process must be a session leader and * not have a controlling tty already. @@ -2433,17 +2457,16 @@ static int tiocsctty(struct tty_struct *tty, int arg) /* * Steal it away */ - read_lock(&tasklist_lock); session_clear_tty(tty->session); - read_unlock(&tasklist_lock); } else { ret = -EPERM; goto unlock; } } - proc_set_tty(current, tty); + proc_set_tty(tty); unlock: - mutex_unlock(&tty_mutex); + read_unlock(&tasklist_lock); + tty_unlock(tty); return ret; } @@ -2468,6 +2491,27 @@ struct pid *tty_get_pgrp(struct tty_struct *tty) } EXPORT_SYMBOL_GPL(tty_get_pgrp); +/* + * This checks not only the pgrp, but falls back on the pid if no + * satisfactory pgrp is found. I dunno - gdb doesn't work correctly + * without this... + * + * The caller must hold rcu lock or the tasklist lock. + */ +static struct pid *session_of_pgrp(struct pid *pgrp) +{ + struct task_struct *p; + struct pid *sid = NULL; + + p = pid_task(pgrp, PIDTYPE_PGID); + if (p == NULL) + p = pid_task(pgrp, PIDTYPE_PID); + if (p != NULL) + sid = task_session(p); + + return sid; +} + /** * tiocgpgrp - get process group * @tty: tty passed by user @@ -2714,23 +2758,35 @@ static int tty_tiocgicount(struct tty_struct *tty, void __user *arg) return 0; } -struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) +static void tty_warn_deprecated_flags(struct serial_struct __user *ss) { - if (tty->driver->type == TTY_DRIVER_TYPE_PTY && - tty->driver->subtype == PTY_TYPE_MASTER) - tty = tty->link; - return tty; + static DEFINE_RATELIMIT_STATE(depr_flags, + DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); + char comm[TASK_COMM_LEN]; + int flags; + + if (get_user(flags, &ss->flags)) + return; + + flags &= ASYNC_DEPRECATED; + + if (flags && __ratelimit(&depr_flags)) + pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n", + __func__, get_task_comm(comm, current), flags); } -EXPORT_SYMBOL(tty_pair_get_tty); -struct tty_struct *tty_pair_get_pty(struct tty_struct *tty) +/* + * if pty, return the slave side (real_tty) + * otherwise, return self + */ +static struct tty_struct *tty_pair_get_tty(struct tty_struct *tty) { if (tty->driver->type == TTY_DRIVER_TYPE_PTY && tty->driver->subtype == PTY_TYPE_MASTER) - return tty; - return tty->link; + tty = tty->link; + return tty; } -EXPORT_SYMBOL(tty_pair_get_pty); /* * Split this up, as gcc can choke on it otherwise.. @@ -2859,13 +2915,16 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case TCIFLUSH: case TCIOFLUSH: /* flush tty buffer and allow ldisc to process ioctl */ - tty_buffer_flush(tty); + tty_buffer_flush(tty, NULL); break; } break; + case TIOCSSERIAL: + tty_warn_deprecated_flags(p); + break; } if (tty->ops->ioctl) { - retval = (tty->ops->ioctl)(tty, cmd, arg); + retval = tty->ops->ioctl(tty, cmd, arg); if (retval != -ENOIOCTLCMD) return retval; } @@ -2892,7 +2951,7 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd, return -EINVAL; if (tty->ops->compat_ioctl) { - retval = (tty->ops->compat_ioctl)(tty, cmd, arg); + retval = tty->ops->compat_ioctl(tty, cmd, arg); if (retval != -ENOIOCTLCMD) return retval; } @@ -3443,59 +3502,6 @@ dev_t tty_devnum(struct tty_struct *tty) } EXPORT_SYMBOL(tty_devnum); -void proc_clear_tty(struct task_struct *p) -{ - unsigned long flags; - struct tty_struct *tty; - spin_lock_irqsave(&p->sighand->siglock, flags); - tty = p->signal->tty; - p->signal->tty = NULL; - spin_unlock_irqrestore(&p->sighand->siglock, flags); - tty_kref_put(tty); -} - -/* Called under the sighand lock */ - -static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) -{ - if (tty) { - unsigned long flags; - /* We should not have a session or pgrp to put here but.... */ - spin_lock_irqsave(&tty->ctrl_lock, flags); - put_pid(tty->session); - put_pid(tty->pgrp); - tty->pgrp = get_pid(task_pgrp(tsk)); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - tty->session = get_pid(task_session(tsk)); - if (tsk->signal->tty) { - printk(KERN_DEBUG "tty not NULL!!\n"); - tty_kref_put(tsk->signal->tty); - } - } - put_pid(tsk->signal->tty_old_pgrp); - tsk->signal->tty = tty_kref_get(tty); - tsk->signal->tty_old_pgrp = NULL; -} - -static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) -{ - spin_lock_irq(&tsk->sighand->siglock); - __proc_set_tty(tsk, tty); - spin_unlock_irq(&tsk->sighand->siglock); -} - -struct tty_struct *get_current_tty(void) -{ - struct tty_struct *tty; - unsigned long flags; - - spin_lock_irqsave(¤t->sighand->siglock, flags); - tty = tty_kref_get(current->signal->tty); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); - return tty; -} -EXPORT_SYMBOL_GPL(get_current_tty); - void tty_default_fops(struct file_operations *fops) { *fops = tty_fops; |