zfs/include/sys/dmu_zfetch.h

   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 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*
  27  * Copyright (c) 2014 by Delphix. All rights reserved.
  28  */
  29
  30 #ifndef _DMU_ZFETCH_H
  31 #define _DMU_ZFETCH_H
  32
  33 #include <sys/zfs_context.h>
  34
  35 #ifdef  __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 extern unsigned long    zfetch_array_rd_sz;
  40
  41 struct dnode;                           /* so we can reference dnode */
  42
  43 typedef struct zstream {
  44         uint64_t        zs_blkid;       /* expect next access at this blkid */
  45         uint64_t        zs_pf_blkid;    /* next block to prefetch */
  46
  47         /*
  48          * We will next prefetch the L1 indirect block of this level-0
  49          * block id.
  50          */
  51         uint64_t        zs_ipf_blkid;
  52
  53         kmutex_t        zs_lock;        /* protects stream */
  54         hrtime_t        zs_atime;       /* time last prefetch issued */
  55         list_node_t     zs_node;        /* link for zf_stream */
  56 } zstream_t;
  57
  58 typedef struct zfetch {
  59         krwlock_t       zf_rwlock;      /* protects zfetch structure */
  60         list_t          zf_stream;      /* list of zstream_t's */
  61         struct dnode    *zf_dnode;      /* dnode that owns this zfetch */
  62 } zfetch_t;
  63
  64 void            zfetch_init(void);
  65 void            zfetch_fini(void);
  66
  67 void            dmu_zfetch_init(zfetch_t *, struct dnode *);
  68 void            dmu_zfetch_fini(zfetch_t *);
  69 void            dmu_zfetch(zfetch_t *, uint64_t, uint64_t, boolean_t);
  70
  71
  72 #ifdef  __cplusplus
  73 }
  74 #endif
  75
  76 #endif  /* _DMU_ZFETCH_H */