arc.h revision 260763 
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2013 by Delphix. All rights reserved.
24 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
25 */
26
27#ifndef	_SYS_ARC_H
28#define	_SYS_ARC_H
29
30#include <sys/zfs_context.h>
31
32#ifdef	__cplusplus
33extern "C" {
34#endif
35
36#include <sys/zio.h>
37#include <sys/dmu.h>
38#include <sys/spa.h>
39
40typedef struct arc_buf_hdr arc_buf_hdr_t;
41typedef struct arc_buf arc_buf_t;
42typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *priv);
43typedef int arc_evict_func_t(void *priv);
44
45/* generic arc_done_func_t's which you can use */
46arc_done_func_t arc_bcopy_func;
47arc_done_func_t arc_getbuf_func;
48
49struct arc_buf {
50	arc_buf_hdr_t		*b_hdr;
51	arc_buf_t		*b_next;
52	kmutex_t		b_evict_lock;
53	void			*b_data;
54	arc_evict_func_t	*b_efunc;
55	void			*b_private;
56};
57
58typedef enum arc_buf_contents {
59	ARC_BUFC_DATA,				/* buffer contains data */
60	ARC_BUFC_METADATA,			/* buffer contains metadata */
61	ARC_BUFC_NUMTYPES
62} arc_buf_contents_t;
63/*
64 * These are the flags we pass into calls to the arc
65 */
66#define	ARC_WAIT	(1 << 1)	/* perform I/O synchronously */
67#define	ARC_NOWAIT	(1 << 2)	/* perform I/O asynchronously */
68#define	ARC_PREFETCH	(1 << 3)	/* I/O is a prefetch */
69#define	ARC_CACHED	(1 << 4)	/* I/O was already in cache */
70#define	ARC_L2CACHE	(1 << 5)	/* cache in L2ARC */
71#define	ARC_L2COMPRESS	(1 << 6)	/* compress in L2ARC */
72
73/*
74 * The following breakdows of arc_size exist for kstat only.
75 */
76typedef enum arc_space_type {
77	ARC_SPACE_DATA,
78	ARC_SPACE_HDRS,
79	ARC_SPACE_L2HDRS,
80	ARC_SPACE_OTHER,
81	ARC_SPACE_NUMTYPES
82} arc_space_type_t;
83
84void arc_space_consume(uint64_t space, arc_space_type_t type);
85void arc_space_return(uint64_t space, arc_space_type_t type);
86void *arc_data_buf_alloc(uint64_t space);
87void arc_data_buf_free(void *buf, uint64_t space);
88arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag,
89    arc_buf_contents_t type);
90arc_buf_t *arc_loan_buf(spa_t *spa, int size);
91void arc_return_buf(arc_buf_t *buf, void *tag);
92void arc_loan_inuse_buf(arc_buf_t *buf, void *tag);
93void arc_buf_add_ref(arc_buf_t *buf, void *tag);
94boolean_t arc_buf_remove_ref(arc_buf_t *buf, void *tag);
95int arc_buf_size(arc_buf_t *buf);
96void arc_release(arc_buf_t *buf, void *tag);
97int arc_released(arc_buf_t *buf);
98int arc_has_callback(arc_buf_t *buf);
99void arc_buf_freeze(arc_buf_t *buf);
100void arc_buf_thaw(arc_buf_t *buf);
101boolean_t arc_buf_eviction_needed(arc_buf_t *buf);
102#ifdef ZFS_DEBUG
103int arc_referenced(arc_buf_t *buf);
104#endif
105
106int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
107    arc_done_func_t *done, void *priv, zio_priority_t priority, int flags,
108    uint32_t *arc_flags, const zbookmark_t *zb);
109zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg,
110    blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, boolean_t l2arc_compress,
111    const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *physdone,
112    arc_done_func_t *done, void *priv, zio_priority_t priority,
113    int zio_flags, const zbookmark_t *zb);
114void arc_freed(spa_t *spa, const blkptr_t *bp);
115
116void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *priv);
117int arc_buf_evict(arc_buf_t *buf);
118
119void arc_flush(spa_t *spa);
120void arc_tempreserve_clear(uint64_t reserve);
121int arc_tempreserve_space(uint64_t reserve, uint64_t txg);
122
123void arc_init(void);
124void arc_fini(void);
125
126/*
127 * Level 2 ARC
128 */
129
130void l2arc_add_vdev(spa_t *spa, vdev_t *vd);
131void l2arc_remove_vdev(vdev_t *vd);
132boolean_t l2arc_vdev_present(vdev_t *vd);
133void l2arc_init(void);
134void l2arc_fini(void);
135void l2arc_start(void);
136void l2arc_stop(void);
137
138#ifdef illumos
139#ifndef _KERNEL
140extern boolean_t arc_watch;
141extern int arc_procfd;
142#endif
143#endif /* illumos */
144
145#ifdef	__cplusplus
146}
147#endif
148
149#endif /* _SYS_ARC_H */
150