1168404Spjd/* 2168404Spjd * CDDL HEADER START 3168404Spjd * 4168404Spjd * The contents of this file are subject to the terms of the 5168404Spjd * Common Development and Distribution License (the "License"). 6168404Spjd * You may not use this file except in compliance with the License. 7168404Spjd * 8168404Spjd * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9168404Spjd * or http://www.opensolaris.org/os/licensing. 10168404Spjd * See the License for the specific language governing permissions 11168404Spjd * and limitations under the License. 12168404Spjd * 13168404Spjd * When distributing Covered Code, include this CDDL HEADER in each 14168404Spjd * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15168404Spjd * If applicable, add the following below this CDDL HEADER, with the 16168404Spjd * fields enclosed by brackets "[]" replaced with your own identifying 17168404Spjd * information: Portions Copyright [yyyy] [name of copyright owner] 18168404Spjd * 19168404Spjd * CDDL HEADER END 20168404Spjd */ 21168404Spjd/* 22219089Spjd * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23307277Smav * Copyright (c) 2012, 2015 by Delphix. All rights reserved. 24168404Spjd */ 25168404Spjd 26168404Spjd#ifndef _SYS_REFCOUNT_H 27168404Spjd#define _SYS_REFCOUNT_H 28168404Spjd 29185029Spjd#include <sys/cdefs.h> 30185029Spjd#include <sys/types.h> 31179310Spjd#include_next <sys/refcount.h> 32168404Spjd#include <sys/list.h> 33168404Spjd#include <sys/zfs_context.h> 34168404Spjd 35168404Spjd#ifdef __cplusplus 36168404Spjdextern "C" { 37168404Spjd#endif 38168404Spjd 39168404Spjd/* 40168404Spjd * If the reference is held only by the calling function and not any 41168404Spjd * particular object, use FTAG (which is a string) for the holder_tag. 42168404Spjd * Otherwise, use the object that holds the reference. 43168404Spjd */ 44331399Smav#define FTAG ((char *)(uintptr_t)__func__) 45168404Spjd 46219089Spjd#ifdef ZFS_DEBUG 47168404Spjdtypedef struct reference { 48168404Spjd list_node_t ref_link; 49168404Spjd void *ref_holder; 50168404Spjd uint64_t ref_number; 51168404Spjd uint8_t *ref_removed; 52168404Spjd} reference_t; 53168404Spjd 54168404Spjdtypedef struct refcount { 55168404Spjd kmutex_t rc_mtx; 56248571Smm boolean_t rc_tracked; 57168404Spjd list_t rc_list; 58168404Spjd list_t rc_removed; 59246651Smm uint64_t rc_count; 60246651Smm uint64_t rc_removed_count; 61168404Spjd} refcount_t; 62168404Spjd 63248571Smm/* Note: refcount_t must be initialized with refcount_create[_untracked]() */ 64168404Spjd 65168404Spjdvoid refcount_create(refcount_t *rc); 66248571Smmvoid refcount_create_untracked(refcount_t *rc); 67307277Smavvoid refcount_create_tracked(refcount_t *rc); 68168404Spjdvoid refcount_destroy(refcount_t *rc); 69168404Spjdvoid refcount_destroy_many(refcount_t *rc, uint64_t number); 70168404Spjdint refcount_is_zero(refcount_t *rc); 71168404Spjdint64_t refcount_count(refcount_t *rc); 72168404Spjdint64_t refcount_add(refcount_t *rc, void *holder_tag); 73168404Spjdint64_t refcount_remove(refcount_t *rc, void *holder_tag); 74168404Spjdint64_t refcount_add_many(refcount_t *rc, uint64_t number, void *holder_tag); 75168404Spjdint64_t refcount_remove_many(refcount_t *rc, uint64_t number, void *holder_tag); 76219089Spjdvoid refcount_transfer(refcount_t *dst, refcount_t *src); 77307265Smavvoid refcount_transfer_ownership(refcount_t *, void *, void *); 78307277Smavboolean_t refcount_held(refcount_t *, void *); 79307277Smavboolean_t refcount_not_held(refcount_t *, void *); 80168404Spjd 81179310Spjdvoid refcount_sysinit(void); 82168404Spjdvoid refcount_fini(void); 83168404Spjd 84219089Spjd#else /* ZFS_DEBUG */ 85168404Spjd 86168404Spjdtypedef struct refcount { 87168404Spjd uint64_t rc_count; 88168404Spjd} refcount_t; 89168404Spjd 90168404Spjd#define refcount_create(rc) ((rc)->rc_count = 0) 91248571Smm#define refcount_create_untracked(rc) ((rc)->rc_count = 0) 92307277Smav#define refcount_create_tracked(rc) ((rc)->rc_count = 0) 93168404Spjd#define refcount_destroy(rc) ((rc)->rc_count = 0) 94168404Spjd#define refcount_destroy_many(rc, number) ((rc)->rc_count = 0) 95168404Spjd#define refcount_is_zero(rc) ((rc)->rc_count == 0) 96168404Spjd#define refcount_count(rc) ((rc)->rc_count) 97270247Sdelphij#define refcount_add(rc, holder) atomic_inc_64_nv(&(rc)->rc_count) 98270247Sdelphij#define refcount_remove(rc, holder) atomic_dec_64_nv(&(rc)->rc_count) 99168404Spjd#define refcount_add_many(rc, number, holder) \ 100168404Spjd atomic_add_64_nv(&(rc)->rc_count, number) 101168404Spjd#define refcount_remove_many(rc, number, holder) \ 102168404Spjd atomic_add_64_nv(&(rc)->rc_count, -number) 103219089Spjd#define refcount_transfer(dst, src) { \ 104219089Spjd uint64_t __tmp = (src)->rc_count; \ 105219089Spjd atomic_add_64(&(src)->rc_count, -__tmp); \ 106219089Spjd atomic_add_64(&(dst)->rc_count, __tmp); \ 107219089Spjd} 108321535Smav#define refcount_transfer_ownership(rc, current_holder, new_holder) (void)0 109307277Smav#define refcount_held(rc, holder) ((rc)->rc_count > 0) 110307277Smav#define refcount_not_held(rc, holder) (B_TRUE) 111168404Spjd 112179310Spjd#define refcount_sysinit() 113168404Spjd#define refcount_fini() 114168404Spjd 115219089Spjd#endif /* ZFS_DEBUG */ 116168404Spjd 117168404Spjd#ifdef __cplusplus 118168404Spjd} 119168404Spjd#endif 120168404Spjd 121168404Spjd#endif /* _SYS_REFCOUNT_H */ 122