--- /dev/null
+/*
+ * 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) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
+ * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
+ */
+
+#ifndef _SYS_ARC_IMPL_H
+#define _SYS_ARC_IMPL_H
+
+#include <sys/arc.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Note that buffers can be in one of 6 states:
+ * ARC_anon - anonymous (discussed below)
+ * ARC_mru - recently used, currently cached
+ * ARC_mru_ghost - recentely used, no longer in cache
+ * ARC_mfu - frequently used, currently cached
+ * ARC_mfu_ghost - frequently used, no longer in cache
+ * ARC_l2c_only - exists in L2ARC but not other states
+ * When there are no active references to the buffer, they are
+ * are linked onto a list in one of these arc states. These are
+ * the only buffers that can be evicted or deleted. Within each
+ * state there are multiple lists, one for meta-data and one for
+ * non-meta-data. Meta-data (indirect blocks, blocks of dnodes,
+ * etc.) is tracked separately so that it can be managed more
+ * explicitly: favored over data, limited explicitly.
+ *
+ * Anonymous buffers are buffers that are not associated with
+ * a DVA. These are buffers that hold dirty block copies
+ * before they are written to stable storage. By definition,
+ * they are "ref'd" and are considered part of arc_mru
+ * that cannot be freed. Generally, they will aquire a DVA
+ * as they are written and migrate onto the arc_mru list.
+ *
+ * The ARC_l2c_only state is for buffers that are in the second
+ * level ARC but no longer in any of the ARC_m* lists. The second
+ * level ARC itself may also contain buffers that are in any of
+ * the ARC_m* states - meaning that a buffer can exist in two
+ * places. The reason for the ARC_l2c_only state is to keep the
+ * buffer header in the hash table, so that reads that hit the
+ * second level ARC benefit from these fast lookups.
+ */
+
+typedef struct arc_state {
+ list_t arcs_list[ARC_BUFC_NUMTYPES]; /* list of evictable buffers */
+ uint64_t arcs_lsize[ARC_BUFC_NUMTYPES]; /* amount of evictable data */
+ uint64_t arcs_size; /* total amount of data in this state */
+ kmutex_t arcs_mtx;
+ arc_state_type_t arcs_state;
+} arc_state_t;
+
+typedef struct l2arc_buf_hdr l2arc_buf_hdr_t;
+
+typedef struct arc_callback arc_callback_t;
+
+struct arc_callback {
+ void *acb_private;
+ arc_done_func_t *acb_done;
+ arc_buf_t *acb_buf;
+ zio_t *acb_zio_dummy;
+ arc_callback_t *acb_next;
+};
+
+typedef struct arc_write_callback arc_write_callback_t;
+
+struct arc_write_callback {
+ void *awcb_private;
+ arc_done_func_t *awcb_ready;
+ arc_done_func_t *awcb_physdone;
+ arc_done_func_t *awcb_done;
+ arc_buf_t *awcb_buf;
+};
+
+struct arc_buf_hdr {
+ /* protected by hash lock */
+ dva_t b_dva;
+ uint64_t b_birth;
+ uint64_t b_cksum0;
+
+ kmutex_t b_freeze_lock;
+ zio_cksum_t *b_freeze_cksum;
+
+ arc_buf_hdr_t *b_hash_next;
+ arc_buf_t *b_buf;
+ uint32_t b_flags;
+ uint32_t b_datacnt;
+
+ arc_callback_t *b_acb;
+ kcondvar_t b_cv;
+
+ /* immutable */
+ arc_buf_contents_t b_type;
+ uint64_t b_size;
+ uint64_t b_spa;
+
+ /* protected by arc state mutex */
+ arc_state_t *b_state;
+ list_node_t b_arc_node;
+
+ /* updated atomically */
+ clock_t b_arc_access;
+ uint32_t b_mru_hits;
+ uint32_t b_mru_ghost_hits;
+ uint32_t b_mfu_hits;
+ uint32_t b_mfu_ghost_hits;
+ uint32_t b_l2_hits;
+
+ /* self protecting */
+ refcount_t b_refcnt;
+
+ l2arc_buf_hdr_t *b_l2hdr;
+ list_node_t b_l2node;
+};
+
+typedef struct l2arc_dev {
+ vdev_t *l2ad_vdev; /* vdev */
+ spa_t *l2ad_spa; /* spa */
+ uint64_t l2ad_hand; /* next write location */
+ uint64_t l2ad_start; /* first addr on device */
+ uint64_t l2ad_end; /* last addr on device */
+ uint64_t l2ad_evict; /* last addr eviction reached */
+ boolean_t l2ad_first; /* first sweep through */
+ boolean_t l2ad_writing; /* currently writing */
+ list_t *l2ad_buflist; /* buffer list */
+ list_node_t l2ad_node; /* device list node */
+} l2arc_dev_t;
+
+typedef struct l2arc_write_callback {
+ l2arc_dev_t *l2wcb_dev; /* device info */
+ arc_buf_hdr_t *l2wcb_head; /* head of write buflist */
+} l2arc_write_callback_t;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _SYS_ARC_IMPL_H */
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