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 */ 26 27 #ifndef _SYS_ARC_H 28 #define _SYS_ARC_H 29 30 #include <sys/zfs_context.h> 31 32 #ifdef __cplusplus 33 extern "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 59 typedef struct arc_buf_hdr arc_buf_hdr_t; 60 typedef struct arc_buf arc_buf_t; 61 typedef void arc_read_done_func_t(zio_t *zio, const zbookmark_phys_t *zb, 62 const blkptr_t *bp, arc_buf_t *buf, void *private); 63 typedef void arc_write_done_func_t(zio_t *zio, arc_buf_t *buf, void *priv); 64 65 /* generic arc_done_func_t's which you can use */ 66 arc_read_done_func_t arc_bcopy_func; 67 arc_read_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 ARC_FLAG_PRESCIENT_PREFETCH = 1 << 6, /* long min lifespan */ 81 82 /* 83 * Private ARC flags. These flags are private ARC only flags that 84 * will show up in b_flags in the arc_hdr_buf_t. These flags should 85 * only be set by ARC code. 86 */ 87 ARC_FLAG_IN_HASH_TABLE = 1 << 7, /* buffer is hashed */ 88 ARC_FLAG_IO_IN_PROGRESS = 1 << 8, /* I/O in progress */ 89 ARC_FLAG_IO_ERROR = 1 << 9, /* I/O failed for buf */ 90 ARC_FLAG_INDIRECT = 1 << 10, /* indirect block */ 91 /* Indicates that block was read with ASYNC priority. */ 92 ARC_FLAG_PRIO_ASYNC_READ = 1 << 11, 93 ARC_FLAG_L2_WRITING = 1 << 12, /* write in progress */ 94 ARC_FLAG_L2_EVICTED = 1 << 13, /* evicted during I/O */ 95 ARC_FLAG_L2_WRITE_HEAD = 1 << 14, /* head of write list */ 96 /* indicates that the buffer contains metadata (otherwise, data) */ 97 ARC_FLAG_BUFC_METADATA = 1 << 15, 98 99 /* Flags specifying whether optional hdr struct fields are defined */ 100 ARC_FLAG_HAS_L1HDR = 1 << 16, 101 ARC_FLAG_HAS_L2HDR = 1 << 17, 102 103 /* 104 * Indicates the arc_buf_hdr_t's b_pdata matches the on-disk data. 105 * This allows the l2arc to use the blkptr's checksum to verify 106 * the data without having to store the checksum in the hdr. 107 */ 108 ARC_FLAG_COMPRESSED_ARC = 1 << 18, 109 ARC_FLAG_SHARED_DATA = 1 << 19, 110 111 /* 112 * The arc buffer's compression mode is stored in the top 7 bits of the 113 * flags field, so these dummy flags are included so that MDB can 114 * interpret the enum properly. 115 */ 116 ARC_FLAG_COMPRESS_0 = 1 << 24, 117 ARC_FLAG_COMPRESS_1 = 1 << 25, 118 ARC_FLAG_COMPRESS_2 = 1 << 26, 119 ARC_FLAG_COMPRESS_3 = 1 << 27, 120 ARC_FLAG_COMPRESS_4 = 1 << 28, 121 ARC_FLAG_COMPRESS_5 = 1 << 29, 122 ARC_FLAG_COMPRESS_6 = 1 << 30 123 124 } arc_flags_t; 125 126 typedef enum arc_buf_flags { 127 ARC_BUF_FLAG_SHARED = 1 << 0, 128 ARC_BUF_FLAG_COMPRESSED = 1 << 1 129 } arc_buf_flags_t; 130 131 struct arc_buf { 132 arc_buf_hdr_t *b_hdr; 133 arc_buf_t *b_next; 134 kmutex_t b_evict_lock; 135 void *b_data; 136 arc_buf_flags_t b_flags; 137 }; 138 139 typedef enum arc_buf_contents { 140 ARC_BUFC_INVALID, /* invalid type */ 141 ARC_BUFC_DATA, /* buffer contains data */ 142 ARC_BUFC_METADATA, /* buffer contains metadata */ 143 ARC_BUFC_NUMTYPES 144 } arc_buf_contents_t; 145 146 /* 147 * The following breakdows of arc_size exist for kstat only. 148 */ 149 typedef enum arc_space_type { 150 ARC_SPACE_DATA, 151 ARC_SPACE_META, 152 ARC_SPACE_HDRS, 153 ARC_SPACE_L2HDRS, 154 ARC_SPACE_OTHER, 155 ARC_SPACE_BONUS, 156 ARC_SPACE_NUMTYPES 157 } arc_space_type_t; 158 159 void arc_space_consume(uint64_t space, arc_space_type_t type); 160 void arc_space_return(uint64_t space, arc_space_type_t type); 161 boolean_t arc_is_metadata(arc_buf_t *buf); 162 enum zio_compress arc_get_compression(arc_buf_t *buf); 163 int arc_decompress(arc_buf_t *buf); 164 arc_buf_t *arc_alloc_buf(spa_t *spa, void *tag, arc_buf_contents_t type, 165 int32_t size); 166 arc_buf_t *arc_alloc_compressed_buf(spa_t *spa, void *tag, 167 uint64_t psize, uint64_t lsize, enum zio_compress compression_type); 168 arc_buf_t *arc_loan_buf(spa_t *spa, boolean_t is_metadata, int size); 169 arc_buf_t *arc_loan_compressed_buf(spa_t *spa, uint64_t psize, uint64_t lsize, 170 enum zio_compress compression_type); 171 void arc_return_buf(arc_buf_t *buf, void *tag); 172 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag); 173 void arc_buf_destroy(arc_buf_t *buf, void *tag); 174 int arc_buf_size(arc_buf_t *buf); 175 int arc_buf_lsize(arc_buf_t *buf); 176 void arc_buf_access(arc_buf_t *buf); 177 void arc_release(arc_buf_t *buf, void *tag); 178 int arc_released(arc_buf_t *buf); 179 void arc_buf_freeze(arc_buf_t *buf); 180 void arc_buf_thaw(arc_buf_t *buf); 181 #ifdef ZFS_DEBUG 182 int arc_referenced(arc_buf_t *buf); 183 #endif 184 185 int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 186 arc_read_done_func_t *done, void *private, zio_priority_t priority, 187 int flags, arc_flags_t *arc_flags, const zbookmark_phys_t *zb); 188 zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg, 189 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, const zio_prop_t *zp, 190 arc_write_done_func_t *ready, arc_write_done_func_t *child_ready, 191 arc_write_done_func_t *physdone, arc_write_done_func_t *done, 192 void *private, zio_priority_t priority, int zio_flags, 193 const zbookmark_phys_t *zb); 194 void arc_freed(spa_t *spa, const blkptr_t *bp); 195 196 void arc_flush(spa_t *spa, boolean_t retry); 197 void arc_tempreserve_clear(uint64_t reserve); 198 int arc_tempreserve_space(spa_t *spa, uint64_t reserve, uint64_t txg); 199 200 uint64_t arc_max_bytes(void); 201 void arc_init(void); 202 void arc_fini(void); 203 204 /* 205 * Level 2 ARC 206 */ 207 208 void l2arc_add_vdev(spa_t *spa, vdev_t *vd); 209 void l2arc_remove_vdev(vdev_t *vd); 210 boolean_t l2arc_vdev_present(vdev_t *vd); 211 void l2arc_init(void); 212 void l2arc_fini(void); 213 void l2arc_start(void); 214 void l2arc_stop(void); 215 216 #ifndef _KERNEL 217 extern boolean_t arc_watch; 218 extern int arc_procfd; 219 #endif 220 221 #ifdef __cplusplus 222 } 223 #endif 224 225 #endif /* _SYS_ARC_H */ 226