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) 2012, 2016 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
40/*
41 * Used by arc_flush() to inform arc_evict_state() that it should evict
42 * all available buffers from the arc state being passed in.
43 */
44#define ARC_EVICT_ALL -1ULL
45
46#define HDR_SET_LSIZE(hdr, x) do { \
47 ASSERT(IS_P2ALIGNED(x, 1U << SPA_MINBLOCKSHIFT)); \
48 (hdr)->b_lsize = ((x) >> SPA_MINBLOCKSHIFT); \
49_NOTE(CONSTCOND) } while (0)
50
51#define HDR_SET_PSIZE(hdr, x) do { \
52 ASSERT(IS_P2ALIGNED((x), 1U << SPA_MINBLOCKSHIFT)); \
53 (hdr)->b_psize = ((x) >> SPA_MINBLOCKSHIFT); \
54_NOTE(CONSTCOND) } while (0)
55
56#define HDR_GET_LSIZE(hdr) ((hdr)->b_lsize << SPA_MINBLOCKSHIFT)
57#define HDR_GET_PSIZE(hdr) ((hdr)->b_psize << SPA_MINBLOCKSHIFT)
58
59typedef struct arc_buf_hdr arc_buf_hdr_t;
60typedef struct arc_buf arc_buf_t;
61typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *priv);
62
63/* generic arc_done_func_t's which you can use */
64arc_done_func_t arc_bcopy_func;
65arc_done_func_t arc_getbuf_func;
66
67extern int zfs_arc_num_sublists_per_state;
68
69typedef enum arc_flags
70{
71 /*
72 * Public flags that can be passed into the ARC by external consumers.
73 */
74 ARC_FLAG_WAIT = 1 << 0, /* perform sync I/O */
75 ARC_FLAG_NOWAIT = 1 << 1, /* perform async I/O */
76 ARC_FLAG_PREFETCH = 1 << 2, /* I/O is a prefetch */
77 ARC_FLAG_CACHED = 1 << 3, /* I/O was in cache */
78 ARC_FLAG_L2CACHE = 1 << 4, /* cache in L2ARC */
79 ARC_FLAG_PREDICTIVE_PREFETCH = 1 << 5, /* I/O from zfetch */
80
81 /*
82 * Private ARC flags. These flags are private ARC only flags that
83 * will show up in b_flags in the arc_hdr_buf_t. These flags should
84 * only be set by ARC code.
85 */
86 ARC_FLAG_IN_HASH_TABLE = 1 << 6, /* buffer is hashed */
87 ARC_FLAG_IO_IN_PROGRESS = 1 << 7, /* I/O in progress */
88 ARC_FLAG_IO_ERROR = 1 << 8, /* I/O failed for buf */
89 ARC_FLAG_INDIRECT = 1 << 9, /* indirect block */
90 /* Indicates that block was read with ASYNC priority. */
91 ARC_FLAG_PRIO_ASYNC_READ = 1 << 10,
92 ARC_FLAG_L2_WRITING = 1 << 11, /* write in progress */
93 ARC_FLAG_L2_EVICTED = 1 << 12, /* evicted during I/O */
94 ARC_FLAG_L2_WRITE_HEAD = 1 << 13, /* head of write list */
95 /* indicates that the buffer contains metadata (otherwise, data) */
96 ARC_FLAG_BUFC_METADATA = 1 << 14,
97
98 /* Flags specifying whether optional hdr struct fields are defined */
99 ARC_FLAG_HAS_L1HDR = 1 << 15,
100 ARC_FLAG_HAS_L2HDR = 1 << 16,
101
102 /*
103 * Indicates the arc_buf_hdr_t's b_pdata matches the on-disk data.
104 * This allows the l2arc to use the blkptr's checksum to verify
105 * the data without having to store the checksum in the hdr.
106 */
107 ARC_FLAG_COMPRESSED_ARC = 1 << 17,
108 ARC_FLAG_SHARED_DATA = 1 << 18,
109
110 /*
111 * The arc buffer's compression mode is stored in the top 7 bits of the
112 * flags field, so these dummy flags are included so that MDB can
113 * interpret the enum properly.
114 */
115 ARC_FLAG_COMPRESS_0 = 1 << 24,
116 ARC_FLAG_COMPRESS_1 = 1 << 25,
117 ARC_FLAG_COMPRESS_2 = 1 << 26,
118 ARC_FLAG_COMPRESS_3 = 1 << 27,
119 ARC_FLAG_COMPRESS_4 = 1 << 28,
120 ARC_FLAG_COMPRESS_5 = 1 << 29,
121 ARC_FLAG_COMPRESS_6 = 1 << 30
122
123} arc_flags_t;
124
125struct arc_buf {
126 arc_buf_hdr_t *b_hdr;
127 arc_buf_t *b_next;
128 kmutex_t b_evict_lock;
129 void *b_data;
130};
131
132typedef enum arc_buf_contents {
133 ARC_BUFC_INVALID, /* invalid type */
134 ARC_BUFC_DATA, /* buffer contains data */
135 ARC_BUFC_METADATA, /* buffer contains metadata */
136 ARC_BUFC_NUMTYPES
137} arc_buf_contents_t;
138
139/*
140 * The following breakdows of arc_size exist for kstat only.
141 */
142typedef enum arc_space_type {
143 ARC_SPACE_DATA,
144 ARC_SPACE_META,
145 ARC_SPACE_HDRS,
146 ARC_SPACE_L2HDRS,
147 ARC_SPACE_OTHER,
148 ARC_SPACE_NUMTYPES
149} arc_space_type_t;
150
151void arc_space_consume(uint64_t space, arc_space_type_t type);
152void arc_space_return(uint64_t space, arc_space_type_t type);
153arc_buf_t *arc_alloc_buf(spa_t *spa, int32_t size, void *tag,
154 arc_buf_contents_t type);
155arc_buf_t *arc_loan_buf(spa_t *spa, int size);
156void arc_return_buf(arc_buf_t *buf, void *tag);
157void arc_loan_inuse_buf(arc_buf_t *buf, void *tag);
158void arc_buf_destroy(arc_buf_t *buf, void *tag);
159int arc_buf_size(arc_buf_t *buf);
160void arc_release(arc_buf_t *buf, void *tag);
161int arc_released(arc_buf_t *buf);
162void arc_buf_freeze(arc_buf_t *buf);
163void arc_buf_thaw(arc_buf_t *buf);
164#ifdef ZFS_DEBUG
165int arc_referenced(arc_buf_t *buf);
166#endif
167
168int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
169 arc_done_func_t *done, void *priv, zio_priority_t priority, int flags,
170 arc_flags_t *arc_flags, const zbookmark_phys_t *zb);
171zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg,
172 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, const zio_prop_t *zp,
173 arc_done_func_t *ready, arc_done_func_t *child_ready,
174 arc_done_func_t *physdone, arc_done_func_t *done,
175 void *priv, zio_priority_t priority, int zio_flags,
176 const zbookmark_phys_t *zb);
177void arc_freed(spa_t *spa, const blkptr_t *bp);
178
179void arc_flush(spa_t *spa, boolean_t retry);
180void arc_tempreserve_clear(uint64_t reserve);
181int arc_tempreserve_space(uint64_t reserve, uint64_t txg);
182
183uint64_t arc_max_bytes(void);
184void arc_init(void);
185void arc_fini(void);
186
187/*
188 * Level 2 ARC
189 */
190
191void l2arc_add_vdev(spa_t *spa, vdev_t *vd);
192void l2arc_remove_vdev(vdev_t *vd);
193boolean_t l2arc_vdev_present(vdev_t *vd);
194void l2arc_init(void);
195void l2arc_fini(void);
196void l2arc_start(void);
197void l2arc_stop(void);
198
199#ifdef illumos
200#ifndef _KERNEL
201extern boolean_t arc_watch;
202extern int arc_procfd;
203#endif
204#endif /* illumos */
205
206#ifdef __cplusplus
207}
208#endif
209
210#endif /* _SYS_ARC_H */
211