dsl_scan.h revision 268650 
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) 2013 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
35extern "C" {
36#endif
37
38struct objset;
39struct dsl_dir;
40struct dsl_dataset;
41struct dsl_pool;
42struct dmu_tx;
43
44/*
45 * All members of this structure must be uint64_t, for byteswap
46 * purposes.
47 */
48typedef 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_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
71typedef enum dsl_scan_flags {
72	DSF_VISIT_DS_AGAIN = 1<<0,
73} dsl_scan_flags_t;
74
75/*
76 * Every pool will have one dsl_scan_t and this structure will contain
77 * in-memory information about the scan and a pointer to the on-disk
78 * representation (i.e. dsl_scan_phys_t). Most of the state of the scan
79 * is contained on-disk to allow the scan to resume in the event of a reboot
80 * or panic. This structure maintains information about the behavior of a
81 * running scan, some caching information, and how it should traverse the pool.
82 *
83 * The following members of this structure direct the behavior of the scan:
84 *
85 * scn_pausing -	a scan that cannot be completed in a single txg or
86 *			has exceeded its allotted time will need to pause.
87 *			When this flag is set the scanner will stop traversing
88 *			the pool and write out the current state to disk.
89 *
90 * scn_restart_txg -	directs the scanner to either restart or start a
91 *			a scan at the specified txg value.
92 *
93 * scn_done_txg -	when a scan completes its traversal it will set
94 *			the completion txg to the next txg. This is necessary
95 *			to ensure that any blocks that were freed during
96 *			the scan but have not yet been processed (i.e deferred
97 *			frees) are accounted for.
98 *
99 * This structure also maintains information about deferred frees which are
100 * a special kind of traversal. Deferred free can exist in either a bptree or
101 * a bpobj structure. The scn_is_bptree flag will indicate the type of
102 * deferred free that is in progress. If the deferred free is part of an
103 * asynchronous destroy then the scn_async_destroying flag will be set.
104 */
105typedef struct dsl_scan {
106	struct dsl_pool *scn_dp;
107
108	boolean_t scn_pausing;
109	uint64_t scn_restart_txg;
110	uint64_t scn_done_txg;
111	uint64_t scn_sync_start_time;
112	zio_t *scn_zio_root;
113
114	/* for freeing blocks */
115	boolean_t scn_is_bptree;
116	boolean_t scn_async_destroying;
117	boolean_t scn_async_stalled;
118
119	/* for debugging / information */
120	uint64_t scn_visited_this_txg;
121
122	dsl_scan_phys_t scn_phys;
123} dsl_scan_t;
124
125int dsl_scan_init(struct dsl_pool *dp, uint64_t txg);
126void dsl_scan_fini(struct dsl_pool *dp);
127void dsl_scan_sync(struct dsl_pool *, dmu_tx_t *);
128int dsl_scan_cancel(struct dsl_pool *);
129int dsl_scan(struct dsl_pool *, pool_scan_func_t);
130void dsl_resilver_restart(struct dsl_pool *, uint64_t txg);
131boolean_t dsl_scan_resilvering(struct dsl_pool *dp);
132boolean_t dsl_dataset_unstable(struct dsl_dataset *ds);
133void dsl_scan_ddt_entry(dsl_scan_t *scn, enum zio_checksum checksum,
134    ddt_entry_t *dde, dmu_tx_t *tx);
135void dsl_scan_ds_destroyed(struct dsl_dataset *ds, struct dmu_tx *tx);
136void dsl_scan_ds_snapshotted(struct dsl_dataset *ds, struct dmu_tx *tx);
137void dsl_scan_ds_clone_swapped(struct dsl_dataset *ds1, struct dsl_dataset *ds2,
138    struct dmu_tx *tx);
139boolean_t dsl_scan_active(dsl_scan_t *scn);
140
141#ifdef	__cplusplus
142}
143#endif
144
145#endif /* _SYS_DSL_SCAN_H */
146