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7a4e0d2c7f
According to Greg, in the context of magic numbers as defined in magic-number.rst, "the tty layer should not need this and I'll gladly take patches" Acked-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Ref: https://lore.kernel.org/linux-doc/YyMlovoskUcHLEb7@kroah.com/ Link: https://lore.kernel.org/r/476d024cd6b04160a5de381ea2b9856b60088cbd.1663288066.git.nabijaczleweli@nabijaczleweli.xyz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
56 lines
994 B
C
56 lines
994 B
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/tty.h>
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#include <linux/module.h>
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#include <linux/kallsyms.h>
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#include <linux/semaphore.h>
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#include <linux/sched.h>
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#include "tty.h"
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/* Legacy tty mutex glue */
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/*
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* Getting the big tty mutex.
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*/
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void tty_lock(struct tty_struct *tty)
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{
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tty_kref_get(tty);
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mutex_lock(&tty->legacy_mutex);
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}
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EXPORT_SYMBOL(tty_lock);
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int tty_lock_interruptible(struct tty_struct *tty)
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{
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int ret;
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tty_kref_get(tty);
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ret = mutex_lock_interruptible(&tty->legacy_mutex);
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if (ret)
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tty_kref_put(tty);
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return ret;
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}
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void tty_unlock(struct tty_struct *tty)
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{
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mutex_unlock(&tty->legacy_mutex);
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tty_kref_put(tty);
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}
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EXPORT_SYMBOL(tty_unlock);
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void tty_lock_slave(struct tty_struct *tty)
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{
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if (tty && tty != tty->link)
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tty_lock(tty);
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}
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void tty_unlock_slave(struct tty_struct *tty)
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{
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if (tty && tty != tty->link)
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tty_unlock(tty);
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}
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void tty_set_lock_subclass(struct tty_struct *tty)
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{
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lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
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}
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