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, 2014 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 typedef struct arc_buf_hdr arc_buf_hdr_t; 47 typedef struct arc_buf arc_buf_t; 48 typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *private); 49 typedef int arc_evict_func_t(void *private); 50 51 /* generic arc_done_func_t's which you can use */ 52 arc_done_func_t arc_bcopy_func; 53 arc_done_func_t arc_getbuf_func; 54 55 typedef enum arc_flags 56 { 57 /* 58 * Public flags that can be passed into the ARC by external consumers. 59 */ 60 ARC_FLAG_NONE = 1 << 0, /* No flags set */ 61 ARC_FLAG_WAIT = 1 << 1, /* perform sync I/O */ 62 ARC_FLAG_NOWAIT = 1 << 2, /* perform async I/O */ 63 ARC_FLAG_PREFETCH = 1 << 3, /* I/O is a prefetch */ 64 ARC_FLAG_CACHED = 1 << 4, /* I/O was in cache */ 65 ARC_FLAG_L2CACHE = 1 << 5, /* cache in L2ARC */ 66 ARC_FLAG_L2COMPRESS = 1 << 6, /* compress in L2ARC */ 67 ARC_FLAG_PREDICTIVE_PREFETCH = 1 << 7, /* I/O from zfetch */ 68 69 /* 70 * Private ARC flags. These flags are private ARC only flags that 71 * will show up in b_flags in the arc_hdr_buf_t. These flags should 72 * only be set by ARC code. 73 */ 74 ARC_FLAG_IN_HASH_TABLE = 1 << 8, /* buffer is hashed */ 75 ARC_FLAG_IO_IN_PROGRESS = 1 << 9, /* I/O in progress */ 76 ARC_FLAG_IO_ERROR = 1 << 10, /* I/O failed for buf */ 77 ARC_FLAG_FREED_IN_READ = 1 << 11, /* freed during read */ 78 ARC_FLAG_BUF_AVAILABLE = 1 << 12, /* block not in use */ 79 ARC_FLAG_INDIRECT = 1 << 13, /* indirect block */ 80 /* Indicates that block was read with ASYNC priority. */ 81 ARC_FLAG_PRIO_ASYNC_READ = 1 << 14, 82 ARC_FLAG_L2_WRITING = 1 << 15, /* write in progress */ 83 ARC_FLAG_L2_EVICTED = 1 << 16, /* evicted during I/O */ 84 ARC_FLAG_L2_WRITE_HEAD = 1 << 17, /* head of write list */ 85 /* indicates that the buffer contains metadata (otherwise, data) */ 86 ARC_FLAG_BUFC_METADATA = 1 << 18, 87 88 /* Flags specifying whether optional hdr struct fields are defined */ 89 ARC_FLAG_HAS_L1HDR = 1 << 19, 90 ARC_FLAG_HAS_L2HDR = 1 << 20, 91 92 93 /* 94 * The arc buffer's compression mode is stored in the top 7 bits of the 95 * flags field, so these dummy flags are included so that MDB can 96 * interpret the enum properly. 97 */ 98 ARC_FLAG_COMPRESS_0 = 1 << 24, 99 ARC_FLAG_COMPRESS_1 = 1 << 25, 100 ARC_FLAG_COMPRESS_2 = 1 << 26, 101 ARC_FLAG_COMPRESS_3 = 1 << 27, 102 ARC_FLAG_COMPRESS_4 = 1 << 28, 103 ARC_FLAG_COMPRESS_5 = 1 << 29, 104 ARC_FLAG_COMPRESS_6 = 1 << 30 105 106 } arc_flags_t; 107 108 struct arc_buf { 109 arc_buf_hdr_t *b_hdr; 110 arc_buf_t *b_next; 111 kmutex_t b_evict_lock; 112 void *b_data; 113 arc_evict_func_t *b_efunc; 114 void *b_private; 115 }; 116 117 typedef enum arc_buf_contents { 118 ARC_BUFC_DATA, /* buffer contains data */ 119 ARC_BUFC_METADATA, /* buffer contains metadata */ 120 ARC_BUFC_NUMTYPES 121 } arc_buf_contents_t; 122 123 /* 124 * The following breakdows of arc_size exist for kstat only. 125 */ 126 typedef enum arc_space_type { 127 ARC_SPACE_DATA, 128 ARC_SPACE_META, 129 ARC_SPACE_HDRS, 130 ARC_SPACE_L2HDRS, 131 ARC_SPACE_OTHER, 132 ARC_SPACE_NUMTYPES 133 } arc_space_type_t; 134 135 void arc_space_consume(uint64_t space, arc_space_type_t type); 136 void arc_space_return(uint64_t space, arc_space_type_t type); 137 arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag, 138 arc_buf_contents_t type); 139 arc_buf_t *arc_loan_buf(spa_t *spa, int size); 140 void arc_return_buf(arc_buf_t *buf, void *tag); 141 void arc_loan_inuse_buf(arc_buf_t *buf, void *tag); 142 void arc_buf_add_ref(arc_buf_t *buf, void *tag); 143 boolean_t arc_buf_remove_ref(arc_buf_t *buf, void *tag); 144 int arc_buf_size(arc_buf_t *buf); 145 void arc_release(arc_buf_t *buf, void *tag); 146 int arc_released(arc_buf_t *buf); 147 void arc_buf_freeze(arc_buf_t *buf); 148 void arc_buf_thaw(arc_buf_t *buf); 149 boolean_t arc_buf_eviction_needed(arc_buf_t *buf); 150 #ifdef ZFS_DEBUG 151 int arc_referenced(arc_buf_t *buf); 152 #endif 153 154 int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 155 arc_done_func_t *done, void *private, zio_priority_t priority, int flags, 156 arc_flags_t *arc_flags, const zbookmark_phys_t *zb); 157 zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg, 158 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, boolean_t l2arc_compress, 159 const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *physdone, 160 arc_done_func_t *done, void *private, zio_priority_t priority, 161 int zio_flags, const zbookmark_phys_t *zb); 162 void arc_freed(spa_t *spa, const blkptr_t *bp); 163 164 void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *private); 165 boolean_t arc_clear_callback(arc_buf_t *buf); 166 167 void arc_flush(spa_t *spa, boolean_t retry); 168 void arc_tempreserve_clear(uint64_t reserve); 169 int arc_tempreserve_space(uint64_t reserve, uint64_t txg); 170 171 void arc_init(void); 172 void arc_fini(void); 173 174 /* 175 * Level 2 ARC 176 */ 177 178 void l2arc_add_vdev(spa_t *spa, vdev_t *vd); 179 void l2arc_remove_vdev(vdev_t *vd); 180 boolean_t l2arc_vdev_present(vdev_t *vd); 181 void l2arc_init(void); 182 void l2arc_fini(void); 183 void l2arc_start(void); 184 void l2arc_stop(void); 185 186 #ifndef _KERNEL 187 extern boolean_t arc_watch; 188 extern int arc_procfd; 189 #endif 190 191 #ifdef __cplusplus 192 } 193 #endif 194 195 #endif /* _SYS_ARC_H */ 196