1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see [sun.com URL with a
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright 2008 Sun Microsystems, Inc. All rights reserved
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * libcfs/include/libcfs/user-lock.h
38 * Author: Nikita Danilov <nikita@clusterfs.com>
41 #ifndef __LIBCFS_USER_LOCK_H__
42 #define __LIBCFS_USER_LOCK_H__
44 #ifndef __LIBCFS_LIBCFS_H__
45 #error Do not #include this file directly. #include <libcfs/libcfs.h> instead
48 /* Implementations of portable synchronization APIs for liblustre */
51 * liblustre is single-threaded, so most "synchronization" APIs are trivial.
53 * XXX Liang: There are several branches share lnet with b_hd_newconfig,
54 * if we define lock APIs at here, there will be conflict with liblustre
61 * The userspace implementations of linux/spinlock.h vary; we just
62 * include our own for all of them
64 #define __LINUX_SPINLOCK_H
67 * Optional debugging (magic stamping and checking ownership) can be added.
78 * - spin_lock_irqsave(x, f)
79 * - spin_unlock_irqrestore(x, f)
81 * No-op implementation.
83 struct spin_lock {int foo;};
85 typedef struct spin_lock spinlock_t;
87 #define SPIN_LOCK_UNLOCKED (spinlock_t) { }
88 #define LASSERT_SPIN_LOCKED(lock) do {} while(0)
89 #define LASSERT_SEM_LOCKED(sem) do {} while(0)
91 void spin_lock_init(spinlock_t *lock);
92 void spin_lock(spinlock_t *lock);
93 void spin_unlock(spinlock_t *lock);
94 int spin_trylock(spinlock_t *lock);
95 void spin_lock_bh_init(spinlock_t *lock);
96 void spin_lock_bh(spinlock_t *lock);
97 void spin_unlock_bh(spinlock_t *lock);
99 static inline int spin_is_locked(spinlock_t *l) {return 1;}
100 static inline void spin_lock_irqsave(spinlock_t *l, unsigned long f){}
101 static inline void spin_unlock_irqrestore(spinlock_t *l, unsigned long f){}
110 typedef struct semaphore {
114 void sema_init(struct semaphore *s, int val);
115 void __down(struct semaphore *s);
116 void __up(struct semaphore *s);
122 * - init_mutex_locked(x)
126 #define DECLARE_MUTEX(name) \
127 struct semaphore name = { 1 }
129 #define mutex_up(s) __up(s)
130 #define up(s) mutex_up(s)
131 #define mutex_down(s) __down(s)
132 #define down(s) mutex_down(s)
134 #define init_MUTEX(x) sema_init(x, 1)
135 #define init_MUTEX_LOCKED(x) sema_init(x, 0)
136 #define init_mutex(s) init_MUTEX(s)
141 * - init_completion(c)
143 * - wait_for_completion(c)
150 void init_completion(struct completion *c);
151 void complete(struct completion *c);
152 void wait_for_completion(struct completion *c);
154 #define COMPLETION_INITIALIZER(work) \
155 { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
157 #define DECLARE_COMPLETION(work) \
158 struct completion work = COMPLETION_INITIALIZER(work)
160 #define INIT_COMPLETION(x) ((x).done = 0)
172 struct rw_semaphore {
176 void init_rwsem(struct rw_semaphore *s);
177 void down_read(struct rw_semaphore *s);
178 int down_read_trylock(struct rw_semaphore *s);
179 void down_write(struct rw_semaphore *s);
180 int down_write_trylock(struct rw_semaphore *s);
181 void up_read(struct rw_semaphore *s);
182 void up_write(struct rw_semaphore *s);
185 * read-write lock : Need to be investigated more!!
186 * XXX nikita: for now, let rwlock_t to be identical to rw_semaphore
188 * - DECLARE_RWLOCK(l)
195 typedef struct rw_semaphore rwlock_t;
196 #define RW_LOCK_UNLOCKED (rwlock_t) { }
198 #define rwlock_init(pl) init_rwsem(pl)
200 #define read_lock(l) down_read(l)
201 #define read_unlock(l) up_read(l)
202 #define write_lock(l) down_write(l)
203 #define write_unlock(l) up_write(l)
206 write_lock_irqsave(rwlock_t *l, unsigned long f) { write_lock(l); }
208 write_unlock_irqrestore(rwlock_t *l, unsigned long f) { write_unlock(l); }
211 read_lock_irqsave(rwlock_t *l, unsigned long f) { read_lock(l); }
213 read_unlock_irqrestore(rwlock_t *l, unsigned long f) { read_unlock(l); }
216 * Atomic for user-space
217 * Copied from liblustre
219 typedef struct { volatile int counter; } atomic_t;
221 #define ATOMIC_INIT(i) { (i) }
223 #define atomic_read(a) ((a)->counter)
224 #define atomic_set(a,b) do {(a)->counter = b; } while (0)
225 #define atomic_dec_and_test(a) ((--((a)->counter)) == 0)
226 #define atomic_dec_and_lock(a,b) ((--((a)->counter)) == 0)
227 #define atomic_inc(a) (((a)->counter)++)
228 #define atomic_dec(a) do { (a)->counter--; } while (0)
229 #define atomic_add(b,a) do {(a)->counter += b;} while (0)
230 #define atomic_add_return(n,a) ((a)->counter += n)
231 #define atomic_inc_return(a) atomic_add_return(1,a)
232 #define atomic_sub(b,a) do {(a)->counter -= b;} while (0)
233 #define atomic_sub_return(n,a) ((a)->counter -= n)
234 #define atomic_dec_return(a) atomic_sub_return(1,a)
237 #ifdef HAVE_LIBPTHREAD
244 struct cfs_completion {
246 pthread_cond_t c_cond;
247 pthread_mutex_t c_mut;
250 void cfs_init_completion(struct cfs_completion *c);
251 void cfs_fini_completion(struct cfs_completion *c);
252 void cfs_complete(struct cfs_completion *c);
253 void cfs_wait_for_completion(struct cfs_completion *c);
259 typedef struct { volatile int counter; } cfs_atomic_t;
261 int cfs_atomic_read(cfs_atomic_t *a);
262 void cfs_atomic_set(cfs_atomic_t *a, int b);
263 int cfs_atomic_dec_and_test(cfs_atomic_t *a);
264 void cfs_atomic_inc(cfs_atomic_t *a);
265 void cfs_atomic_dec(cfs_atomic_t *a);
266 void cfs_atomic_add(int b, cfs_atomic_t *a);
267 void cfs_atomic_sub(int b, cfs_atomic_t *a);
269 #endif /* HAVE_LIBPTHREAD */
274 /* __LIBCFS_USER_LOCK_H__ */
278 * c-indentation-style: "K&R"