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 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_ARC_H 27 #define _SYS_ARC_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #include <sys/zfs_context.h> 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 #include <sys/zio.h> 38 39 typedef struct arc_buf_hdr arc_buf_hdr_t; 40 typedef struct arc_buf arc_buf_t; 41 typedef void arc_done_func_t(zio_t *zio, arc_buf_t *buf, void *private); 42 typedef void arc_byteswap_func_t(void *buf, size_t size); 43 typedef int arc_evict_func_t(void *private); 44 45 /* generic arc_done_func_t's which you can use */ 46 arc_done_func_t arc_bcopy_func; 47 arc_done_func_t arc_getbuf_func; 48 49 struct arc_buf { 50 arc_buf_hdr_t *b_hdr; 51 arc_buf_t *b_next; 52 void *b_data; 53 arc_evict_func_t *b_efunc; 54 void *b_private; 55 }; 56 57 typedef enum arc_buf_contents { 58 ARC_BUFC_UNDEF, /* buffer contents undefined */ 59 ARC_BUFC_DATA, /* buffer contains data */ 60 ARC_BUFC_METADATA /* buffer contains metadata */ 61 } arc_buf_contents_t; 62 /* 63 * These are the flags we pass into calls to the arc 64 */ 65 #define ARC_WAIT (1 << 1) /* perform I/O synchronously */ 66 #define ARC_NOWAIT (1 << 2) /* perform I/O asynchronously */ 67 #define ARC_PREFETCH (1 << 3) /* I/O is a prefetch */ 68 #define ARC_CACHED (1 << 4) /* I/O was already in cache */ 69 70 arc_buf_t *arc_buf_alloc(spa_t *spa, int size, void *tag, 71 arc_buf_contents_t type); 72 void arc_buf_add_ref(arc_buf_t *buf, void *tag); 73 int arc_buf_remove_ref(arc_buf_t *buf, void *tag); 74 int arc_buf_size(arc_buf_t *buf); 75 void arc_release(arc_buf_t *buf, void *tag); 76 int arc_released(arc_buf_t *buf); 77 int arc_has_callback(arc_buf_t *buf); 78 void arc_buf_freeze(arc_buf_t *buf); 79 void arc_buf_thaw(arc_buf_t *buf); 80 #ifdef ZFS_DEBUG 81 int arc_referenced(arc_buf_t *buf); 82 #endif 83 84 int arc_read(zio_t *pio, spa_t *spa, blkptr_t *bp, arc_byteswap_func_t *swap, 85 arc_done_func_t *done, void *private, int priority, int flags, 86 uint32_t *arc_flags, zbookmark_t *zb); 87 int arc_write(zio_t *pio, spa_t *spa, int checksum, int compress, int ncopies, 88 uint64_t txg, blkptr_t *bp, arc_buf_t *buf, 89 arc_done_func_t *done, void *private, int priority, int flags, 90 uint32_t arc_flags, zbookmark_t *zb); 91 int arc_free(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, 92 zio_done_func_t *done, void *private, uint32_t arc_flags); 93 int arc_tryread(spa_t *spa, blkptr_t *bp, void *data); 94 95 void arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *private); 96 int arc_buf_evict(arc_buf_t *buf); 97 98 void arc_flush(void); 99 void arc_tempreserve_clear(uint64_t tempreserve); 100 int arc_tempreserve_space(uint64_t tempreserve); 101 102 void arc_init(void); 103 void arc_fini(void); 104 105 #ifdef __cplusplus 106 } 107 #endif 108 109 #endif /* _SYS_ARC_H */ 110