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 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 extern int zfs_arc_num_sublists_per_state; 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 /* 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; 124 125 struct 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 }; 131 132 typedef 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 */ 142 typedef 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; 150 151 void arc_space_consume(uint64_t space, arc_space_type_t type); 152 void arc_space_return(uint64_t space, arc_space_type_t type); 153 arc_buf_t *arc_alloc_buf(spa_t *spa, int32_t size, void *tag, 154 arc_buf_contents_t type); 155 arc_buf_t *arc_loan_buf(spa_t *spa, int size); 156 void arc_return_buf(arc_buf_t *buf, void *tag); 157 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag); 158 void arc_buf_destroy(arc_buf_t *buf, void *tag); 159 int arc_buf_size(arc_buf_t *buf); 160 void arc_release(arc_buf_t *buf, void *tag); 161 int arc_released(arc_buf_t *buf); 162 void arc_buf_freeze(arc_buf_t *buf); 163 void arc_buf_thaw(arc_buf_t *buf); 164 #ifdef ZFS_DEBUG 165 int arc_referenced(arc_buf_t *buf); 166 #endif 167 168 int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 169 arc_done_func_t *done, void *private, zio_priority_t priority, int flags, 170 arc_flags_t *arc_flags, const zbookmark_phys_t *zb); 171 zio_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 *private, zio_priority_t priority, int zio_flags, 176 const zbookmark_phys_t *zb); 177 void arc_freed(spa_t *spa, const blkptr_t *bp); 178 179 void arc_flush(spa_t *spa, boolean_t retry); 180 void arc_tempreserve_clear(uint64_t reserve); 181 int arc_tempreserve_space(uint64_t reserve, uint64_t txg); 182 183 uint64_t arc_max_bytes(void); 184 void arc_init(void); 185 void arc_fini(void); 186 187 /* 188 * Level 2 ARC 189 */ 190 191 void l2arc_add_vdev(spa_t *spa, vdev_t *vd); 192 void l2arc_remove_vdev(vdev_t *vd); 193 boolean_t l2arc_vdev_present(vdev_t *vd); 194 void l2arc_init(void); 195 void l2arc_fini(void); 196 void l2arc_start(void); 197 void l2arc_stop(void); 198 199 #ifndef _KERNEL 200 extern boolean_t arc_watch; 201 extern int arc_procfd; 202 #endif 203 204 #ifdef __cplusplus 205 } 206 #endif 207 208 #endif /* _SYS_ARC_H */ 209