/*

 * 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_ARC_H

#define	_SYS_ARC_H

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/zfs_context.h>

#ifdef	__cplusplus

extern "C" {

#endif

#include <sys/zio.h>

typedef struct arc_buf_hdr arc_buf_hdr_t;

typedef struct arc_buf arc_buf_t;

typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *private);

typedef void arc_byteswap_func_t(void *buf, size_t size);

typedef int arc_evict_func_t(void *private);

/* generic arc_done_func_t's which you can use */

arc_done_func_t arc_bcopy_func;

arc_done_func_t arc_getbuf_func;

struct arc_buf {

	arc_buf_hdr_t		*b_hdr;

	arc_buf_t		*b_next;

	void			*b_data;

	arc_evict_func_t	*b_efunc;

	void			*b_private;

};

/*

 * These are the flags we pass into calls to the arc

 */

#define	ARC_WAIT	(1 << 1)	/* perform I/O synchronously */

#define	ARC_NOWAIT	(1 << 2)	/* perform I/O asynchronously */

#define	ARC_PREFETCH	(1 << 3)	/* I/O is a prefetch */

#define	ARC_CACHED	(1 << 4)	/* I/O was already in cache */

arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag);

void arc_buf_add_ref(arc_buf_t *buf, void *tag);

int arc_buf_remove_ref(arc_buf_t *buf, void *tag);

int arc_buf_size(arc_buf_t *buf);

void arc_release(arc_buf_t *buf, void *tag);

int arc_released(arc_buf_t *buf);

int arc_has_callback(arc_buf_t *buf);

#ifdef ZFS_DEBUG

int arc_referenced(arc_buf_t *buf);

#endif

int arc_read(zio_t *pio, spa_t *spa, blkptr_t *bp, arc_byteswap_func_t *swap,

    arc_done_func_t *done, void *private, int priority, int flags,

    uint32_t *arc_flags, zbookmark_t *zb);

int arc_write(zio_t *pio, spa_t *spa, int checksum, int compress, int ncopies,

    uint64_t txg, blkptr_t *bp, arc_buf_t *buf,

    arc_done_func_t *done, void *private, int priority, int flags,

    uint32_t arc_flags, zbookmark_t *zb);

int arc_free(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,

    zio_done_func_t *done, void *private, uint32_t arc_flags);

int arc_tryread(spa_t *spa, blkptr_t *bp, void *data);

void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *private);

int arc_buf_evict(arc_buf_t *buf);

void arc_flush(void);

void arc_tempreserve_clear(uint64_t tempreserve);

int arc_tempreserve_space(uint64_t tempreserve);

void arc_init(void);

void arc_fini(void);

#ifdef	__cplusplus

}

#endif

#endif /* _SYS_ARC_H */