include/sys/dsl_scan.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 (c) 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
  24  */
  25
  26 #ifndef _SYS_DSL_SCAN_H
  27 #define _SYS_DSL_SCAN_H
  28
  29 #include <sys/zfs_context.h>
  30 #include <sys/zio.h>
  31 #include <sys/ddt.h>
  32 #include <sys/bplist.h>
  33
  34 #ifdef  __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 struct objset;
  39 struct dsl_dir;
  40 struct dsl_dataset;
  41 struct dsl_pool;
  42 struct dmu_tx;
  43
  44 /*
  45  * All members of this structure must be uint64_t, for byteswap
  46  * purposes.
  47  */
  48 typedef struct dsl_scan_phys {
  49         uint64_t scn_func; /* pool_scan_func_t */
  50         uint64_t scn_state; /* dsl_scan_state_t */
  51         uint64_t scn_queue_obj;
  52         uint64_t scn_min_txg;
  53         uint64_t scn_max_txg;
  54         uint64_t scn_cur_min_txg;
  55         uint64_t scn_cur_max_txg;
  56         uint64_t scn_start_time;
  57         uint64_t scn_end_time;
  58         uint64_t scn_to_examine; /* total bytes to be scanned */
  59         uint64_t scn_examined; /* bytes scanned so far */
  60         uint64_t scn_to_process;
  61         uint64_t scn_processed;
  62         uint64_t scn_errors;    /* scan I/O error count */
  63         uint64_t scn_ddt_class_max;
  64         ddt_bookmark_t scn_ddt_bookmark;
  65         zbookmark_phys_t scn_bookmark;
  66         uint64_t scn_flags; /* dsl_scan_flags_t */
  67 } dsl_scan_phys_t;
  68
  69 #define SCAN_PHYS_NUMINTS (sizeof (dsl_scan_phys_t) / sizeof (uint64_t))
  70
  71 typedef enum dsl_scan_flags {
  72         DSF_VISIT_DS_AGAIN = 1<<0,
  73 } dsl_scan_flags_t;
  74
  75 #define DSL_SCAN_FLAGS_MASK (DSF_VISIT_DS_AGAIN)
  76
  77 /*
  78  * Every pool will have one dsl_scan_t and this structure will contain
  79  * in-memory information about the scan and a pointer to the on-disk
  80  * representation (i.e. dsl_scan_phys_t). Most of the state of the scan
  81  * is contained on-disk to allow the scan to resume in the event of a reboot
  82  * or panic. This structure maintains information about the behavior of a
  83  * running scan, some caching information, and how it should traverse the pool.
  84  *
  85  * The following members of this structure direct the behavior of the scan:
  86  *
  87  * scn_pausing -        a scan that cannot be completed in a single txg or
  88  *                      has exceeded its allotted time will need to pause.
  89  *                      When this flag is set the scanner will stop traversing
  90  *                      the pool and write out the current state to disk.
  91  *
  92  * scn_restart_txg -    directs the scanner to either restart or start a
  93  *                      a scan at the specified txg value.
  94  *
  95  * scn_done_txg -       when a scan completes its traversal it will set
  96  *                      the completion txg to the next txg. This is necessary
  97  *                      to ensure that any blocks that were freed during
  98  *                      the scan but have not yet been processed (i.e deferred
  99  *                      frees) are accounted for.
 100  *
 101  * This structure also maintains information about deferred frees which are
 102  * a special kind of traversal. Deferred free can exist in either a bptree or
 103  * a bpobj structure. The scn_is_bptree flag will indicate the type of
 104  * deferred free that is in progress. If the deferred free is part of an
 105  * asynchronous destroy then the scn_async_destroying flag will be set.
 106  */
 107 typedef struct dsl_scan {
 108         struct dsl_pool *scn_dp;
 109
 110         boolean_t scn_pausing;
 111         uint64_t scn_restart_txg;
 112         uint64_t scn_done_txg;
 113         uint64_t scn_sync_start_time;
 114         zio_t *scn_zio_root;
 115
 116         /* for freeing blocks */
 117         boolean_t scn_is_bptree;
 118         boolean_t scn_async_destroying;
 119         boolean_t scn_async_stalled;
 120
 121         /* for debugging / information */
 122         uint64_t scn_visited_this_txg;
 123
 124         dsl_scan_phys_t scn_phys;
 125 } dsl_scan_t;
 126
 127 int dsl_scan_init(struct dsl_pool *dp, uint64_t txg);
 128 void dsl_scan_fini(struct dsl_pool *dp);
 129 void dsl_scan_sync(struct dsl_pool *, dmu_tx_t *);
 130 int dsl_scan_cancel(struct dsl_pool *);
 131 int dsl_scan(struct dsl_pool *, pool_scan_func_t);
 132 void dsl_resilver_restart(struct dsl_pool *, uint64_t txg);
 133 boolean_t dsl_scan_resilvering(struct dsl_pool *dp);
 134 boolean_t dsl_dataset_unstable(struct dsl_dataset *ds);
 135 void dsl_scan_ddt_entry(dsl_scan_t *scn, enum zio_checksum checksum,
 136     ddt_entry_t *dde, dmu_tx_t *tx);
 137 void dsl_scan_ds_destroyed(struct dsl_dataset *ds, struct dmu_tx *tx);
 138 void dsl_scan_ds_snapshotted(struct dsl_dataset *ds, struct dmu_tx *tx);
 139 void dsl_scan_ds_clone_swapped(struct dsl_dataset *ds1, struct dsl_dataset *ds2,
 140     struct dmu_tx *tx);
 141 boolean_t dsl_scan_active(dsl_scan_t *scn);
 142
 143 #ifdef  __cplusplus
 144 }
 145 #endif
 146
 147 #endif /* _SYS_DSL_SCAN_H */