xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/arc.h (revision 088f389458728c464569a5506b58070254fa4f7d)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_ARC_H
27 #define	_SYS_ARC_H
28 
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 #include <sys/zfs_context.h>
32 
33 #ifdef	__cplusplus
34 extern "C" {
35 #endif
36 
37 #include <sys/zio.h>
38 #include <sys/dmu.h>
39 #include <sys/spa.h>
40 
41 typedef struct arc_buf_hdr arc_buf_hdr_t;
42 typedef struct arc_buf arc_buf_t;
43 typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *private);
44 typedef int arc_evict_func_t(void *private);
45 
46 /* generic arc_done_func_t's which you can use */
47 arc_done_func_t arc_bcopy_func;
48 arc_done_func_t arc_getbuf_func;
49 
50 struct arc_buf {
51 	arc_buf_hdr_t		*b_hdr;
52 	arc_buf_t		*b_next;
53 	void			*b_data;
54 	arc_evict_func_t	*b_efunc;
55 	void			*b_private;
56 };
57 
58 typedef 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 
71 void arc_space_consume(uint64_t space);
72 void arc_space_return(uint64_t space);
73 void *arc_data_buf_alloc(uint64_t space);
74 void arc_data_buf_free(void *buf, uint64_t space);
75 arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag,
76     arc_buf_contents_t type);
77 void arc_buf_add_ref(arc_buf_t *buf, void *tag);
78 int arc_buf_remove_ref(arc_buf_t *buf, void *tag);
79 int arc_buf_size(arc_buf_t *buf);
80 void arc_release(arc_buf_t *buf, void *tag);
81 int arc_released(arc_buf_t *buf);
82 int arc_has_callback(arc_buf_t *buf);
83 void arc_buf_freeze(arc_buf_t *buf);
84 void arc_buf_thaw(arc_buf_t *buf);
85 #ifdef ZFS_DEBUG
86 int arc_referenced(arc_buf_t *buf);
87 #endif
88 
89 typedef struct writeprops {
90 	dmu_object_type_t wp_type;
91 	uint8_t wp_copies;
92 	uint8_t wp_level;
93 	uint8_t wp_dncompress, wp_oscompress;
94 	uint8_t wp_dnchecksum, wp_oschecksum;
95 } writeprops_t;
96 
97 int arc_read(zio_t *pio, spa_t *spa, blkptr_t *bp, arc_buf_t *pbuf,
98     arc_done_func_t *done, void *private, int priority, int flags,
99     uint32_t *arc_flags, const zbookmark_t *zb);
100 int arc_read_nolock(zio_t *pio, spa_t *spa, blkptr_t *bp,
101     arc_done_func_t *done, void *private, int priority, int flags,
102     uint32_t *arc_flags, const zbookmark_t *zb);
103 zio_t *arc_write(zio_t *pio, spa_t *spa, const writeprops_t *wp,
104     uint64_t txg, blkptr_t *bp, arc_buf_t *buf,
105     arc_done_func_t *ready, arc_done_func_t *done, void *private, int priority,
106     int flags, const zbookmark_t *zb);
107 int arc_free(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
108     zio_done_func_t *done, void *private, uint32_t arc_flags);
109 int arc_tryread(spa_t *spa, blkptr_t *bp, void *data);
110 
111 void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *private);
112 int arc_buf_evict(arc_buf_t *buf);
113 
114 void arc_flush(spa_t *spa);
115 void arc_tempreserve_clear(uint64_t reserve);
116 int arc_tempreserve_space(uint64_t reserve, uint64_t txg);
117 
118 void arc_init(void);
119 void arc_fini(void);
120 
121 /*
122  * Level 2 ARC
123  */
124 
125 void l2arc_add_vdev(spa_t *spa, vdev_t *vd, uint64_t start, uint64_t end);
126 void l2arc_remove_vdev(vdev_t *vd);
127 boolean_t l2arc_vdev_present(vdev_t *vd);
128 void l2arc_init(void);
129 void l2arc_fini(void);
130 
131 #ifdef	__cplusplus
132 }
133 #endif
134 
135 #endif /* _SYS_ARC_H */
136