arc.h revision 288596
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 33extern "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 46typedef struct arc_buf_hdr arc_buf_hdr_t; 47typedef struct arc_buf arc_buf_t; 48typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *priv); 49typedef int arc_evict_func_t(void *priv); 50 51/* generic arc_done_func_t's which you can use */ 52arc_done_func_t arc_bcopy_func; 53arc_done_func_t arc_getbuf_func; 54 55typedef 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} arc_flags_t; 92 93struct arc_buf { 94 arc_buf_hdr_t *b_hdr; 95 arc_buf_t *b_next; 96 kmutex_t b_evict_lock; 97 void *b_data; 98 arc_evict_func_t *b_efunc; 99 void *b_private; 100}; 101 102typedef enum arc_buf_contents { 103 ARC_BUFC_DATA, /* buffer contains data */ 104 ARC_BUFC_METADATA, /* buffer contains metadata */ 105 ARC_BUFC_NUMTYPES 106} arc_buf_contents_t; 107 108/* 109 * The following breakdows of arc_size exist for kstat only. 110 */ 111typedef enum arc_space_type { 112 ARC_SPACE_DATA, 113 ARC_SPACE_META, 114 ARC_SPACE_HDRS, 115 ARC_SPACE_L2HDRS, 116 ARC_SPACE_OTHER, 117 ARC_SPACE_NUMTYPES 118} arc_space_type_t; 119 120void arc_space_consume(uint64_t space, arc_space_type_t type); 121void arc_space_return(uint64_t space, arc_space_type_t type); 122arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag, 123 arc_buf_contents_t type); 124arc_buf_t *arc_loan_buf(spa_t *spa, int size); 125void arc_return_buf(arc_buf_t *buf, void *tag); 126void arc_loan_inuse_buf(arc_buf_t *buf, void *tag); 127void arc_buf_add_ref(arc_buf_t *buf, void *tag); 128boolean_t arc_buf_remove_ref(arc_buf_t *buf, void *tag); 129int arc_buf_size(arc_buf_t *buf); 130void arc_release(arc_buf_t *buf, void *tag); 131int arc_released(arc_buf_t *buf); 132void arc_buf_freeze(arc_buf_t *buf); 133void arc_buf_thaw(arc_buf_t *buf); 134boolean_t arc_buf_eviction_needed(arc_buf_t *buf); 135#ifdef ZFS_DEBUG 136int arc_referenced(arc_buf_t *buf); 137#endif 138 139int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 140 arc_done_func_t *done, void *priv, zio_priority_t priority, int flags, 141 arc_flags_t *arc_flags, const zbookmark_phys_t *zb); 142zio_t *arc_write(zio_t *pio, spa_t *spa, uint64_t txg, 143 blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, boolean_t l2arc_compress, 144 const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *physdone, 145 arc_done_func_t *done, void *priv, zio_priority_t priority, 146 int zio_flags, const zbookmark_phys_t *zb); 147void arc_freed(spa_t *spa, const blkptr_t *bp); 148 149void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *priv); 150boolean_t arc_clear_callback(arc_buf_t *buf); 151 152void arc_flush(spa_t *spa, boolean_t retry); 153void arc_tempreserve_clear(uint64_t reserve); 154int arc_tempreserve_space(uint64_t reserve, uint64_t txg); 155 156void arc_init(void); 157void arc_fini(void); 158 159/* 160 * Level 2 ARC 161 */ 162 163void l2arc_add_vdev(spa_t *spa, vdev_t *vd); 164void l2arc_remove_vdev(vdev_t *vd); 165boolean_t l2arc_vdev_present(vdev_t *vd); 166void l2arc_init(void); 167void l2arc_fini(void); 168void l2arc_start(void); 169void l2arc_stop(void); 170 171#ifdef illumos 172#ifndef _KERNEL 173extern boolean_t arc_watch; 174extern int arc_procfd; 175#endif 176#endif /* illumos */ 177 178#ifdef __cplusplus 179} 180#endif 181 182#endif /* _SYS_ARC_H */ 183