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Diffstat (limited to 'include/sys/zfs_refcount.h')
| -rw-r--r-- | include/sys/zfs_refcount.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/include/sys/zfs_refcount.h b/include/sys/zfs_refcount.h new file mode 100644 index 000000000..fc0cbea1c --- /dev/null +++ b/include/sys/zfs_refcount.h @@ -0,0 +1,126 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2012, 2015 by Delphix. All rights reserved. + */ + +#ifndef _SYS_ZFS_REFCOUNT_H +#define _SYS_ZFS_REFCOUNT_H + +#include <sys/inttypes.h> +#include <sys/list.h> +#include <sys/zfs_context.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * If the reference is held only by the calling function and not any + * particular object, use FTAG (which is a string) for the holder_tag. + * Otherwise, use the object that holds the reference. + */ +#define FTAG ((char *)(uintptr_t)__func__) + +#ifdef ZFS_DEBUG +typedef struct reference { + list_node_t ref_link; + const void *ref_holder; + uint64_t ref_number; + uint8_t *ref_removed; +} reference_t; + +typedef struct refcount { + kmutex_t rc_mtx; + boolean_t rc_tracked; + list_t rc_list; + list_t rc_removed; + uint64_t rc_count; + uint64_t rc_removed_count; +} zfs_refcount_t; + +/* + * Note: zfs_refcount_t must be initialized with + * refcount_create[_untracked]() + */ + +void zfs_refcount_create(zfs_refcount_t *); +void zfs_refcount_create_untracked(zfs_refcount_t *); +void zfs_refcount_create_tracked(zfs_refcount_t *); +void zfs_refcount_destroy(zfs_refcount_t *); +void zfs_refcount_destroy_many(zfs_refcount_t *, uint64_t); +int zfs_refcount_is_zero(zfs_refcount_t *); +int64_t zfs_refcount_count(zfs_refcount_t *); +int64_t zfs_refcount_add(zfs_refcount_t *, const void *); +int64_t zfs_refcount_remove(zfs_refcount_t *, const void *); +int64_t zfs_refcount_add_many(zfs_refcount_t *, uint64_t, const void *); +int64_t zfs_refcount_remove_many(zfs_refcount_t *, uint64_t, const void *); +void zfs_refcount_transfer(zfs_refcount_t *, zfs_refcount_t *); +void zfs_refcount_transfer_ownership(zfs_refcount_t *, const void *, + const void *); +void zfs_refcount_transfer_ownership_many(zfs_refcount_t *, uint64_t, + const void *, const void *); +boolean_t zfs_refcount_held(zfs_refcount_t *, const void *); +boolean_t zfs_refcount_not_held(zfs_refcount_t *, const void *); + +void zfs_refcount_init(void); +void zfs_refcount_fini(void); + +#else /* ZFS_DEBUG */ + +typedef struct refcount { + uint64_t rc_count; +} zfs_refcount_t; + +#define zfs_refcount_create(rc) ((rc)->rc_count = 0) +#define zfs_refcount_create_untracked(rc) ((rc)->rc_count = 0) +#define zfs_refcount_create_tracked(rc) ((rc)->rc_count = 0) +#define zfs_refcount_destroy(rc) ((rc)->rc_count = 0) +#define zfs_refcount_destroy_many(rc, number) ((rc)->rc_count = 0) +#define zfs_refcount_is_zero(rc) ((rc)->rc_count == 0) +#define zfs_refcount_count(rc) ((rc)->rc_count) +#define zfs_refcount_add(rc, holder) atomic_inc_64_nv(&(rc)->rc_count) +#define zfs_refcount_remove(rc, holder) atomic_dec_64_nv(&(rc)->rc_count) +#define zfs_refcount_add_many(rc, number, holder) \ + atomic_add_64_nv(&(rc)->rc_count, number) +#define zfs_refcount_remove_many(rc, number, holder) \ + atomic_add_64_nv(&(rc)->rc_count, -number) +#define zfs_refcount_transfer(dst, src) { \ + uint64_t __tmp = (src)->rc_count; \ + atomic_add_64(&(src)->rc_count, -__tmp); \ + atomic_add_64(&(dst)->rc_count, __tmp); \ +} +#define zfs_refcount_transfer_ownership(rc, ch, nh) ((void)0) +#define zfs_refcount_transfer_ownership_many(rc, nr, ch, nh) ((void)0) +#define zfs_refcount_held(rc, holder) ((rc)->rc_count > 0) +#define zfs_refcount_not_held(rc, holder) (B_TRUE) + +#define zfs_refcount_init() +#define zfs_refcount_fini() + +#endif /* ZFS_DEBUG */ + +#ifdef __cplusplus +} +#endif + +#endif /* _SYS_REFCOUNT_H */ |