1 /* $NetBSD: shrinker.h,v 1.4 2018/08/27 07:18:18 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUX_SHRINKER_H_ 33 #define _LINUX_SHRINKER_H_ 34 35 struct shrink_control { 36 unsigned long nr_to_scan; 37 }; 38 39 struct shrinker { 40 int (*shrink)(struct shrinker *, struct shrink_control *); 41 unsigned long (*count_objects)(struct shrinker *, 42 struct shrink_control *); 43 unsigned long (*scan_objects)(struct shrinker *, 44 struct shrink_control *); 45 int seeks; 46 }; 47 48 #define SHRINK_STOP (~0UL) 49 50 #define DEFAULT_SEEKS 2 /* XXX cargo-culted from Linux */ 51 52 static inline void 53 register_shrinker(struct shrinker *shrinker __unused) 54 { 55 } 56 57 static inline void 58 unregister_shrinker(struct shrinker *shrinker __unused) 59 { 60 } 61 62 #endif /* _LINUX_SHRINKER_H_ */ 63