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_done_func_t(zio_t *zio, arc_buf_t *buf, void *private); 62 63 /* generic arc_done_func_t's which you can use */ 64 arc_done_func_t arc_bcopy_func; 65 arc_done_func_t arc_getbuf_func; 66 67 typedef enum arc_flags 68 { 69 /* 70 * Public flags that can be passed into the ARC by external consumers. 71 */ 72 ARC_FLAG_WAIT = 1 << 0, /* perform sync I/O */ 73 ARC_FLAG_NOWAIT = 1 << 1, /* perform async I/O */ 74 ARC_FLAG_PREFETCH = 1 << 2, /* I/O is a prefetch */ 75 ARC_FLAG_CACHED = 1 << 3, /* I/O was in cache */ 76 ARC_FLAG_L2CACHE = 1 << 4, /* cache in L2ARC */ 77 ARC_FLAG_PREDICTIVE_PREFETCH = 1 << 5, /* I/O from zfetch */ 78 79 /* 80 * Private ARC flags. These flags are private ARC only flags that 81 * will show up in b_flags in the arc_hdr_buf_t. These flags should 82 * only be set by ARC code. 83 */ 84 ARC_FLAG_IN_HASH_TABLE = 1 << 6, /* buffer is hashed */ 85 ARC_FLAG_IO_IN_PROGRESS = 1 << 7, /* I/O in progress */ 86 ARC_FLAG_IO_ERROR = 1 << 8, /* I/O failed for buf */ 87 ARC_FLAG_INDIRECT = 1 << 9, /* indirect block */ 88 /* Indicates that block was read with ASYNC priority. */ 89 ARC_FLAG_PRIO_ASYNC_READ = 1 << 10, 90 ARC_FLAG_L2_WRITING = 1 << 11, /* write in progress */ 91 ARC_FLAG_L2_EVICTED = 1 << 12, /* evicted during I/O */ 92 ARC_FLAG_L2_WRITE_HEAD = 1 << 13, /* head of write list */ 93 /* indicates that the buffer contains metadata (otherwise, data) */ 94 ARC_FLAG_BUFC_METADATA = 1 << 14, 95 96 /* Flags specifying whether optional hdr struct fields are defined */ 97 ARC_FLAG_HAS_L1HDR = 1 << 15, 98 ARC_FLAG_HAS_L2HDR = 1 << 16, 99 100 /* 101 * Indicates the arc_buf_hdr_t's b_pdata matches the on-disk data. 102 * This allows the l2arc to use the blkptr's checksum to verify 103 * the data without having to store the checksum in the hdr. 104 */ 105 ARC_FLAG_COMPRESSED_ARC = 1 << 17, 106 ARC_FLAG_SHARED_DATA = 1 << 18, 107 108 /* 109 * The arc buffer's compression mode is stored in the top 7 bits of the 110 * flags field, so these dummy flags are included so that MDB can 111 * interpret the enum properly. 112 */ 113 ARC_FLAG_COMPRESS_0 = 1 << 24, 114 ARC_FLAG_COMPRESS_1 = 1 << 25, 115 ARC_FLAG_COMPRESS_2 = 1 << 26, 116 ARC_FLAG_COMPRESS_3 = 1 << 27, 117 ARC_FLAG_COMPRESS_4 = 1 << 28, 118 ARC_FLAG_COMPRESS_5 = 1 << 29, 119 ARC_FLAG_COMPRESS_6 = 1 << 30 120 121 } arc_flags_t; 122 123 typedef enum arc_buf_flags { 124 ARC_BUF_FLAG_SHARED = 1 << 0, 125 ARC_BUF_FLAG_COMPRESSED = 1 << 1 126 } arc_buf_flags_t; 127 128 struct arc_buf { 129 arc_buf_hdr_t *b_hdr; 130 arc_buf_t *b_next; 131 kmutex_t b_evict_lock; 132 void *b_data; 133 arc_buf_flags_t b_flags; 134 }; 135 136 typedef enum arc_buf_contents { 137 ARC_BUFC_INVALID, /* invalid type */ 138 ARC_BUFC_DATA, /* buffer contains data */ 139 ARC_BUFC_METADATA, /* buffer contains metadata */ 140 ARC_BUFC_NUMTYPES 141 } arc_buf_contents_t; 142 143 /* 144 * The following breakdows of arc_size exist for kstat only. 145 */ 146 typedef enum arc_space_type { 147 ARC_SPACE_DATA, 148 ARC_SPACE_META, 149 ARC_SPACE_HDRS, 150 ARC_SPACE_L2HDRS, 151 ARC_SPACE_OTHER, 152 ARC_SPACE_NUMTYPES 153 } arc_space_type_t; 154 155 void arc_space_consume(uint64_t space, arc_space_type_t type); 156 void arc_space_return(uint64_t space, arc_space_type_t type); 157 boolean_t arc_is_metadata(arc_buf_t *buf); 158 enum zio_compress arc_get_compression(arc_buf_t *buf); 159 int arc_decompress(arc_buf_t *buf); 160 arc_buf_t *arc_alloc_buf(spa_t *spa, void *tag, arc_buf_contents_t type, 161 int32_t size); 162 arc_buf_t *arc_alloc_compressed_buf(spa_t *spa, void *tag, 163 uint64_t psize, uint64_t lsize, enum zio_compress compression_type); 164 arc_buf_t *arc_loan_buf(spa_t *spa, boolean_t is_metadata, int size); 165 arc_buf_t *arc_loan_compressed_buf(spa_t *spa, uint64_t psize, uint64_t lsize, 166 enum zio_compress compression_type); 167 void arc_return_buf(arc_buf_t *buf, void *tag); 168 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag); 169 void arc_buf_destroy(arc_buf_t *buf, void *tag); 170 int arc_buf_size(arc_buf_t *buf); 171 int arc_buf_lsize(arc_buf_t *buf); 172 void arc_release(arc_buf_t *buf, void *tag); 173 int arc_released(arc_buf_t *buf); 174 void arc_buf_freeze(arc_buf_t *buf); 175 void arc_buf_thaw(arc_buf_t *buf); 176 #ifdef ZFS_DEBUG 177 int arc_referenced(arc_buf_t *buf); 178 #endif 179 180 int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 181 arc_done_func_t *done, void *private, zio_priority_t priority, int flags, 182 arc_flags_t *arc_flags, const zbookmark_phys_t *zb); 183 zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg, 184 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, const zio_prop_t *zp, 185 arc_done_func_t *ready, arc_done_func_t *child_ready, 186 arc_done_func_t *physdone, arc_done_func_t *done, 187 void *private, zio_priority_t priority, int zio_flags, 188 const zbookmark_phys_t *zb); 189 void arc_freed(spa_t *spa, const blkptr_t *bp); 190 191 void arc_flush(spa_t *spa, boolean_t retry); 192 void arc_tempreserve_clear(uint64_t reserve); 193 int arc_tempreserve_space(uint64_t reserve, uint64_t txg); 194 195 uint64_t arc_max_bytes(void); 196 void arc_init(void); 197 void arc_fini(void); 198 199 /* 200 * Level 2 ARC 201 */ 202 203 void l2arc_add_vdev(spa_t *spa, vdev_t *vd); 204 void l2arc_remove_vdev(vdev_t *vd); 205 boolean_t l2arc_vdev_present(vdev_t *vd); 206 void l2arc_init(void); 207 void l2arc_fini(void); 208 void l2arc_start(void); 209 void l2arc_stop(void); 210 211 #ifndef _KERNEL 212 extern boolean_t arc_watch; 213 extern int arc_procfd; 214 #endif 215 216 #ifdef __cplusplus 217 } 218 #endif 219 220 #endif /* _SYS_ARC_H */ 221