dmu_zfetch.h revision fa9e4066f08beec538e775443c5be79dd423fcab
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _DFETCH_H
#define _DFETCH_H
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/zfs_context.h>
#ifdef __cplusplus
extern "C" {
#endif
extern uint64_t zfetch_array_rd_sz;
struct dnode; /* so we can reference dnode */
typedef enum zfetch_dirn {
ZFETCH_FORWARD = 1, /* prefetch increasing block numbers */
ZFETCH_BACKWARD = -1 /* prefetch decreasing block numbers */
} zfetch_dirn_t;
typedef struct zstream {
uint64_t zst_offset; /* offset of starting block in range */
uint64_t zst_len; /* length of range, in blocks */
zfetch_dirn_t zst_direction; /* direction of prefetch */
uint64_t zst_stride; /* length of stride, in blocks */
uint64_t zst_ph_offset; /* prefetch offset, in blocks */
uint64_t zst_cap; /* prefetch limit (cap), in blocks */
kmutex_t zst_lock; /* protects stream */
clock_t zst_last; /* lbolt of last prefetch */
avl_node_t zst_node; /* embed avl node here */
} zstream_t;
typedef struct zfetch {
krwlock_t zf_rwlock; /* protects zfetch structure */
list_t zf_stream; /* AVL tree of zstream_t's */
struct dnode *zf_dnode; /* dnode that owns this zfetch */
uint32_t zf_stream_cnt; /* # of active streams */
uint64_t zf_alloc_fail; /* # of failed attempts to alloc strm */
} zfetch_t;
void dmu_zfetch_init(zfetch_t *, struct dnode *);
void dmu_zfetch_rele(zfetch_t *);
void dmu_zfetch(zfetch_t *, uint64_t, uint64_t);
#ifdef __cplusplus
}
#endif
#endif /* _DFETCH_H */