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, 2017 by Delphix. All rights reserved.
24 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
25 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
26 */
27
28 #ifndef _SYS_ARC_H
29 #define _SYS_ARC_H
30
31 #include <sys/zfs_context.h>
32
33 #ifdef __cplusplus
34 extern "C" {
35 #endif
36
37 #include <sys/kreplication_common.h>
38 #include <sys/zio.h>
39 #include <sys/dmu.h>
40 #include <sys/spa.h>
41
42 /*
43 * Used by arc_flush() to inform arc_evict_state() that it should evict
44 * all available buffers from the arc state being passed in.
45 */
46 #define ARC_EVICT_ALL -1ULL
47
48 #define HDR_SET_LSIZE(hdr, x) do { \
49 ASSERT(IS_P2ALIGNED(x, 1U << SPA_MINBLOCKSHIFT)); \
50 (hdr)->b_lsize = ((x) >> SPA_MINBLOCKSHIFT); \
51 _NOTE(CONSTCOND) } while (0)
52
53 #define HDR_SET_PSIZE(hdr, x) do { \
54 ASSERT(IS_P2ALIGNED((x), 1U << SPA_MINBLOCKSHIFT)); \
55 (hdr)->b_psize = ((x) >> SPA_MINBLOCKSHIFT); \
56 _NOTE(CONSTCOND) } while (0)
57
58 #define HDR_GET_LSIZE(hdr) ((hdr)->b_lsize << SPA_MINBLOCKSHIFT)
59 #define HDR_GET_PSIZE(hdr) ((hdr)->b_psize << SPA_MINBLOCKSHIFT)
60
61 typedef struct arc_buf_hdr arc_buf_hdr_t;
62 typedef struct arc_buf arc_buf_t;
63 typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *private);
64
65 /* generic arc_done_func_t's which you can use */
66 arc_done_func_t arc_bcopy_func;
67 arc_done_func_t arc_getbuf_func;
68
69 typedef 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
96 /*
97 * Below BUFC flags indicate that either the buffer contains
98 * metadata or DDT metadata. If both of these are not set then the
99 * buffer contains data.
100 * ARC_FLAG_BUFC_DDT is only used when zfs_arc_segregate_ddt is true.
101 * If this tunable is zero ARC_FLAG_BUFC_METADATA is used for both DDT
102 * and regular metadata.
103 */
104 ARC_FLAG_BUFC_METADATA = 1 << 14,
105
106 /* Flags specifying whether optional hdr struct fields are defined */
107 ARC_FLAG_HAS_L1HDR = 1 << 15,
108 ARC_FLAG_HAS_L2HDR = 1 << 16,
109
110 /*
111 * Indicates the arc_buf_hdr_t's b_pdata matches the on-disk data.
112 * This allows the l2arc to use the blkptr's checksum to verify
113 * the data without having to store the checksum in the hdr.
114 */
115 ARC_FLAG_COMPRESSED_ARC = 1 << 17,
116 ARC_FLAG_SHARED_DATA = 1 << 18,
117
118 ARC_FLAG_BUFC_DDT = 1 << 19, /* DDT buf */
119
120 /*
121 * The arc buffer's compression mode is stored in the top 7 bits of the
122 * flags field, so these dummy flags are included so that MDB can
123 * interpret the enum properly.
124 */
125 ARC_FLAG_COMPRESS_0 = 1 << 24,
126 ARC_FLAG_COMPRESS_1 = 1 << 25,
127 ARC_FLAG_COMPRESS_2 = 1 << 26,
128 ARC_FLAG_COMPRESS_3 = 1 << 27,
129 ARC_FLAG_COMPRESS_4 = 1 << 28,
130 ARC_FLAG_COMPRESS_5 = 1 << 29,
131 ARC_FLAG_COMPRESS_6 = 1 << 30
132 } arc_flags_t;
133
134 typedef enum arc_buf_flags {
135 ARC_BUF_FLAG_SHARED = 1 << 0,
136 ARC_BUF_FLAG_COMPRESSED = 1 << 1
137 } arc_buf_flags_t;
138
139 struct arc_buf {
140 arc_buf_hdr_t *b_hdr;
141 arc_buf_t *b_next;
142 kmutex_t b_evict_lock;
143 void *b_data;
144 arc_buf_flags_t b_flags;
145 };
146
147 typedef enum arc_buf_contents {
148 ARC_BUFC_INVALID, /* invalid type */
149 ARC_BUFC_DATA, /* buffer contains data */
150 ARC_BUFC_METADATA, /* buffer contains metadata */
151 ARC_BUFC_DDT, /* buffer contains ddt */
152 ARC_BUFC_NUMTYPES
153 } arc_buf_contents_t;
154
155 /*
156 * The following breakdows of arc_size exist for kstat only.
157 */
158 typedef enum arc_space_type {
159 ARC_SPACE_DATA,
160 ARC_SPACE_META,
161 ARC_SPACE_DDT,
162 ARC_SPACE_HDRS,
163 ARC_SPACE_L2HDRS,
164 ARC_SPACE_OTHER,
165 ARC_SPACE_NUMTYPES
166 } arc_space_type_t;
167
168 /* see spa_misc.c and zio_ddt_write() */
169 extern uint64_t zfs_ddt_byte_ceiling;
170 typedef enum zfs_ddt_limit {
171 DDT_NO_LIMIT = 0,
172 DDT_LIMIT_TO_ARC = 1,
173 DDT_LIMIT_TO_L2ARC = 2,
174 } zfs_ddt_limit_t;
175 extern zfs_ddt_limit_t zfs_ddt_limit_type;
176 extern boolean_t zfs_arc_segregate_ddt;
177 extern uint64_t const * arc_ddt_evict_threshold;
178
179
180 void arc_space_consume(uint64_t space, arc_space_type_t type);
181 void arc_space_return(uint64_t space, arc_space_type_t type);
182 boolean_t arc_is_metadata(arc_buf_t *buf);
183 enum zio_compress arc_get_compression(arc_buf_t *buf);
184 int arc_decompress(arc_buf_t *buf);
185 arc_buf_t *arc_alloc_buf(spa_t *spa, void *tag, arc_buf_contents_t type,
186 int32_t size);
187 arc_buf_t *arc_alloc_compressed_buf(spa_t *spa, void *tag,
188 uint64_t psize, uint64_t lsize, enum zio_compress compression_type);
189 arc_buf_t *arc_loan_buf(spa_t *spa, boolean_t is_metadata, int size);
190 arc_buf_t *arc_loan_compressed_buf(spa_t *spa, uint64_t psize, uint64_t lsize,
191 enum zio_compress compression_type);
192 void arc_return_buf(arc_buf_t *buf, void *tag);
193 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag);
194 void arc_buf_destroy(arc_buf_t *buf, void *tag);
195 int arc_buf_size(arc_buf_t *buf);
196 int arc_buf_lsize(arc_buf_t *buf);
197 void arc_buf_access(arc_buf_t *buf);
198 void arc_release(arc_buf_t *buf, void *tag);
199 int arc_released(arc_buf_t *buf);
200 void arc_buf_freeze(arc_buf_t *buf);
201 void arc_buf_thaw(arc_buf_t *buf);
202 #ifdef ZFS_DEBUG
203 int arc_referenced(arc_buf_t *buf);
204 #endif
205
206 int arc_io_bypass(spa_t *spa, const blkptr_t *bp,
207 arc_bypass_io_func func, void *arg);
208 int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
209 arc_done_func_t *done, void *private, zio_priority_t priority, int flags,
210 arc_flags_t *arc_flags, const zbookmark_phys_t *zb);
211 zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg,
212 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, const zio_prop_t *zp,
213 arc_done_func_t *ready, arc_done_func_t *child_ready,
214 arc_done_func_t *physdone, arc_done_func_t *done,
215 void *private, zio_priority_t priority, int zio_flags,
216 const zbookmark_phys_t *zb, const zio_smartcomp_info_t *smartcomp);
217 void arc_freed(spa_t *spa, const blkptr_t *bp);
218
219 void arc_flush(spa_t *spa, boolean_t retry);
220 void arc_tempreserve_clear(uint64_t reserve);
221 int arc_tempreserve_space(uint64_t reserve, uint64_t txg);
222
223 uint64_t arc_max_bytes(void);
224 void arc_init(void);
225 void arc_fini(void);
226
227 /*
228 * Level 2 ARC
229 */
230
231 void l2arc_add_vdev(spa_t *spa, vdev_t *vd, boolean_t rebuild);
232 void l2arc_remove_vdev(vdev_t *vd);
233 boolean_t l2arc_vdev_present(vdev_t *vd);
234 void l2arc_init(void);
235 void l2arc_fini(void);
236 void l2arc_start(void);
237 void l2arc_stop(void);
238 void l2arc_spa_rebuild_start(spa_t *spa);
239
240 #ifndef _KERNEL
241 extern boolean_t arc_watch;
242 extern int arc_procfd;
243 #endif
244
245 #ifdef __cplusplus
246 }
247 #endif
248
249 #endif /* _SYS_ARC_H */