1 files changed, 103 insertions, 0 deletions
diff --git a/sys/contrib/opensolaris/uts/common/fs/zfs/sys/refcount.h b/sys/contrib/opensolaris/uts/common/fs/zfs/sys/refcount.h
new file mode 100644
index 0000000..4de1cae
--- /dev/null
+++ b/sys/contrib/opensolaris/uts/common/fs/zfs/sys/refcount.h
@@ -0,0 +1,103 @@
+/*
+ * 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 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#ifndef	_SYS_REFCOUNT_H
+#define	_SYS_REFCOUNT_H
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#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 *)__func__)
+
+#if defined(DEBUG) || !defined(_KERNEL)
+typedef struct reference {
+	list_node_t ref_link;
+	void *ref_holder;
+	uint64_t ref_number;
+	uint8_t *ref_removed;
+} reference_t;
+
+typedef struct refcount {
+	kmutex_t rc_mtx;
+	list_t rc_list;
+	list_t rc_removed;
+	int64_t rc_count;
+	int64_t rc_removed_count;
+} refcount_t;
+
+/* Note: refcount_t should be initialized to zero before use. */
+
+void refcount_create(refcount_t *rc);
+void refcount_destroy(refcount_t *rc);
+void refcount_destroy_many(refcount_t *rc, uint64_t number);
+int refcount_is_zero(refcount_t *rc);
+int64_t refcount_count(refcount_t *rc);
+int64_t refcount_add(refcount_t *rc, void *holder_tag);
+int64_t refcount_remove(refcount_t *rc, void *holder_tag);
+int64_t refcount_add_many(refcount_t *rc, uint64_t number, void *holder_tag);
+int64_t refcount_remove_many(refcount_t *rc, uint64_t number, void *holder_tag);
+
+void refcount_init(void);
+void refcount_fini(void);
+
+#else /* DEBUG */
+
+typedef struct refcount {
+	uint64_t rc_count;
+} refcount_t;
+
+#define	refcount_create(rc) ((rc)->rc_count = 0)
+#define	refcount_destroy(rc) ((rc)->rc_count = 0)
+#define	refcount_destroy_many(rc, number) ((rc)->rc_count = 0)
+#define	refcount_is_zero(rc) ((rc)->rc_count == 0)
+#define	refcount_count(rc) ((rc)->rc_count)
+#define	refcount_add(rc, holder) atomic_add_64_nv(&(rc)->rc_count, 1)
+#define	refcount_remove(rc, holder) atomic_add_64_nv(&(rc)->rc_count, -1)
+#define	refcount_add_many(rc, number, holder) \
+	atomic_add_64_nv(&(rc)->rc_count, number)
+#define	refcount_remove_many(rc, number, holder) \
+	atomic_add_64_nv(&(rc)->rc_count, -number)
+
+#define	refcount_init()
+#define	refcount_fini()
+
+#endif /* DEBUG */
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif /* _SYS_REFCOUNT_H */