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Diffstat (limited to 'include/os/linux/spl/sys/mutex.h')
| -rw-r--r-- | include/os/linux/spl/sys/mutex.h | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/include/os/linux/spl/sys/mutex.h b/include/os/linux/spl/sys/mutex.h deleted file mode 100644 index 4eca2414fc5b..000000000000 --- a/include/os/linux/spl/sys/mutex.h +++ /dev/null @@ -1,190 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. - * Copyright (C) 2007 The Regents of the University of California. - * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). - * Written by Brian Behlendorf <behlendorf1@llnl.gov>. - * UCRL-CODE-235197 - * - * This file is part of the SPL, Solaris Porting Layer. - * - * The SPL is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation; either version 2 of the License, or (at your - * option) any later version. - * - * The SPL is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * for more details. - * - * You should have received a copy of the GNU General Public License along - * with the SPL. If not, see <http://www.gnu.org/licenses/>. - */ - -#ifndef _SPL_MUTEX_H -#define _SPL_MUTEX_H - -#include <sys/types.h> -#include <linux/sched.h> -#include <linux/mutex.h> -#include <linux/lockdep.h> -#include <linux/compiler_compat.h> - -typedef enum { - MUTEX_DEFAULT = 0, - MUTEX_SPIN = 1, - MUTEX_ADAPTIVE = 2, - MUTEX_NOLOCKDEP = 3 -} kmutex_type_t; - -typedef struct { - struct mutex m_mutex; - spinlock_t m_lock; /* used for serializing mutex_exit */ - kthread_t *m_owner; -#ifdef CONFIG_LOCKDEP - kmutex_type_t m_type; -#endif /* CONFIG_LOCKDEP */ -} kmutex_t; - -#define MUTEX(mp) (&((mp)->m_mutex)) - -static inline void -spl_mutex_set_owner(kmutex_t *mp) -{ - mp->m_owner = current; -} - -static inline void -spl_mutex_clear_owner(kmutex_t *mp) -{ - mp->m_owner = NULL; -} - -#define mutex_owner(mp) (READ_ONCE((mp)->m_owner)) -#define mutex_owned(mp) (mutex_owner(mp) == current) -#define MUTEX_HELD(mp) mutex_owned(mp) -#define MUTEX_NOT_HELD(mp) (!MUTEX_HELD(mp)) - -#ifdef CONFIG_LOCKDEP -static inline void -spl_mutex_set_type(kmutex_t *mp, kmutex_type_t type) -{ - mp->m_type = type; -} -static inline void -spl_mutex_lockdep_off_maybe(kmutex_t *mp) \ -{ \ - if (mp && mp->m_type == MUTEX_NOLOCKDEP) \ - lockdep_off(); \ -} -static inline void -spl_mutex_lockdep_on_maybe(kmutex_t *mp) \ -{ \ - if (mp && mp->m_type == MUTEX_NOLOCKDEP) \ - lockdep_on(); \ -} -#else /* CONFIG_LOCKDEP */ -#define spl_mutex_set_type(mp, type) -#define spl_mutex_lockdep_off_maybe(mp) -#define spl_mutex_lockdep_on_maybe(mp) -#endif /* CONFIG_LOCKDEP */ - -/* - * The following functions must be a #define and not static inline. - * This ensures that the native linux mutex functions (lock/unlock) - * will be correctly located in the users code which is important - * for the built in kernel lock analysis tools - */ -#undef mutex_init -#define mutex_init(mp, name, type, ibc) \ -{ \ - static struct lock_class_key __key; \ - ASSERT(type == MUTEX_DEFAULT || type == MUTEX_NOLOCKDEP); \ - \ - __mutex_init(MUTEX(mp), (name) ? (#name) : (#mp), &__key); \ - spin_lock_init(&(mp)->m_lock); \ - spl_mutex_clear_owner(mp); \ - spl_mutex_set_type(mp, type); \ -} - -#undef mutex_destroy -#define mutex_destroy(mp) \ -{ \ - VERIFY0P(mutex_owner(mp)); \ -} - -#define mutex_tryenter(mp) \ -/* CSTYLED */ \ -({ \ - int _rc_; \ - \ - spl_mutex_lockdep_off_maybe(mp); \ - if ((_rc_ = mutex_trylock(MUTEX(mp))) == 1) \ - spl_mutex_set_owner(mp); \ - spl_mutex_lockdep_on_maybe(mp); \ - \ - _rc_; \ -}) - -#define NESTED_SINGLE 1 - -#define mutex_enter_nested(mp, subclass) \ -{ \ - ASSERT3P(mutex_owner(mp), !=, current); \ - spl_mutex_lockdep_off_maybe(mp); \ - mutex_lock_nested(MUTEX(mp), (subclass)); \ - spl_mutex_lockdep_on_maybe(mp); \ - spl_mutex_set_owner(mp); \ -} - -#define mutex_enter_interruptible(mp) \ -/* CSTYLED */ \ -({ \ - int _rc_; \ - \ - ASSERT3P(mutex_owner(mp), !=, current); \ - spl_mutex_lockdep_off_maybe(mp); \ - _rc_ = mutex_lock_interruptible(MUTEX(mp)); \ - spl_mutex_lockdep_on_maybe(mp); \ - if (!_rc_) { \ - spl_mutex_set_owner(mp); \ - } \ - \ - _rc_; \ -}) - -#define mutex_enter(mp) mutex_enter_nested((mp), 0) - -/* - * The reason for the spinlock: - * - * The Linux mutex is designed with a fast-path/slow-path design such that it - * does not guarantee serialization upon itself, allowing a race where latter - * acquirers finish mutex_unlock before former ones. - * - * The race renders it unsafe to be used for serializing the freeing of an - * object in which the mutex is embedded, where the latter acquirer could go - * on to free the object while the former one is still doing mutex_unlock and - * causing memory corruption. - * - * However, there are many places in ZFS where the mutex is used for - * serializing object freeing, and the code is shared among other OSes without - * this issue. Thus, we need the spinlock to force the serialization on - * mutex_exit(). - * - * See http://lwn.net/Articles/575477/ for the information about the race. - */ -#define mutex_exit(mp) \ -{ \ - ASSERT3P(mutex_owner(mp), ==, current); \ - spl_mutex_clear_owner(mp); \ - spin_lock(&(mp)->m_lock); \ - spl_mutex_lockdep_off_maybe(mp); \ - mutex_unlock(MUTEX(mp)); \ - spl_mutex_lockdep_on_maybe(mp); \ - spin_unlock(&(mp)->m_lock); \ - /* NOTE: do not dereference mp after this point */ \ -} - -#endif /* _SPL_MUTEX_H */ |