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, 2017 by Delphix. All rights reserved.
24 * Copyright (c) 2017 Datto Inc.
25 */
26
27#ifndef	_SYS_DSL_SCAN_H
28#define	_SYS_DSL_SCAN_H
29
30#include <sys/zfs_context.h>
31#include <sys/zio.h>
32#include <sys/ddt.h>
33#include <sys/bplist.h>
34
35#ifdef	__cplusplus
36extern "C" {
37#endif
38
39struct objset;
40struct dsl_dir;
41struct dsl_dataset;
42struct dsl_pool;
43struct dmu_tx;
44
45/*
46 * All members of this structure must be uint64_t, for byteswap
47 * purposes.
48 */
49typedef struct dsl_scan_phys {
50	uint64_t scn_func; /* pool_scan_func_t */
51	uint64_t scn_state; /* dsl_scan_state_t */
52	uint64_t scn_queue_obj;
53	uint64_t scn_min_txg;
54	uint64_t scn_max_txg;
55	uint64_t scn_cur_min_txg;
56	uint64_t scn_cur_max_txg;
57	uint64_t scn_start_time;
58	uint64_t scn_end_time;
59	uint64_t scn_to_examine; /* total bytes to be scanned */
60	uint64_t scn_examined; /* bytes scanned so far */
61	uint64_t scn_to_process;
62	uint64_t scn_processed;
63	uint64_t scn_errors;	/* scan I/O error count */
64	uint64_t scn_ddt_class_max;
65	ddt_bookmark_t scn_ddt_bookmark;
66	zbookmark_phys_t scn_bookmark;
67	uint64_t scn_flags; /* dsl_scan_flags_t */
68} dsl_scan_phys_t;
69
70#define	SCAN_PHYS_NUMINTS (sizeof (dsl_scan_phys_t) / sizeof (uint64_t))
71
72typedef enum dsl_scan_flags {
73	DSF_VISIT_DS_AGAIN = 1<<0,
74	DSF_SCRUB_PAUSED = 1<<1,
75} dsl_scan_flags_t;
76
77#define	DSL_SCAN_FLAGS_MASK (DSF_VISIT_DS_AGAIN)
78
79/*
80 * Every pool will have one dsl_scan_t and this structure will contain
81 * in-memory information about the scan and a pointer to the on-disk
82 * representation (i.e. dsl_scan_phys_t). Most of the state of the scan
83 * is contained on-disk to allow the scan to resume in the event of a reboot
84 * or panic. This structure maintains information about the behavior of a
85 * running scan, some caching information, and how it should traverse the pool.
86 *
87 * The following members of this structure direct the behavior of the scan:
88 *
89 * scn_suspending -	a scan that cannot be completed in a single txg or
90 *			has exceeded its allotted time will need to suspend.
91 *			When this flag is set the scanner will stop traversing
92 *			the pool and write out the current state to disk.
93 *
94 * scn_restart_txg -	directs the scanner to either restart or start a
95 *			a scan at the specified txg value.
96 *
97 * scn_done_txg -	when a scan completes its traversal it will set
98 *			the completion txg to the next txg. This is necessary
99 *			to ensure that any blocks that were freed during
100 *			the scan but have not yet been processed (i.e deferred
101 *			frees) are accounted for.
102 *
103 * This structure also maintains information about deferred frees which are
104 * a special kind of traversal. Deferred free can exist in either a bptree or
105 * a bpobj structure. The scn_is_bptree flag will indicate the type of
106 * deferred free that is in progress. If the deferred free is part of an
107 * asynchronous destroy then the scn_async_destroying flag will be set.
108 */
109typedef struct dsl_scan {
110	struct dsl_pool *scn_dp;
111	uint64_t scn_restart_txg;
112	uint64_t scn_done_txg;
113	uint64_t scn_sync_start_time;
114	uint64_t scn_issued_before_pass;
115
116	/* for freeing blocks */
117	boolean_t scn_is_bptree;
118	boolean_t scn_async_destroying;
119	boolean_t scn_async_stalled;
120	uint64_t  scn_async_block_min_time_ms;
121
122	/* flags and stats for controlling scan state */
123	boolean_t scn_is_sorted;	/* doing sequential scan */
124	boolean_t scn_clearing;		/* scan is issuing sequential extents */
125	boolean_t scn_checkpointing;	/* scan is issuing all queued extents */
126	boolean_t scn_suspending;	/* scan is suspending until next txg */
127	uint64_t scn_last_checkpoint;	/* time of last checkpoint */
128
129	/* members for thread synchronization */
130	zio_t *scn_zio_root;		/* root zio for waiting on IO */
131	taskq_t *scn_taskq;		/* task queue for issuing extents */
132
133	/* for controlling scan prefetch, protected by spa_scrub_lock */
134	boolean_t scn_prefetch_stop;	/* prefetch should stop */
135	zbookmark_phys_t scn_prefetch_bookmark;	/* prefetch start bookmark */
136	avl_tree_t scn_prefetch_queue;	/* priority queue of prefetch IOs */
137	uint64_t scn_maxinflight_bytes;	/* max bytes in flight for pool */
138
139	/* per txg statistics */
140	uint64_t scn_visited_this_txg;	/* total bps visited this txg */
141	uint64_t scn_holes_this_txg;
142	uint64_t scn_lt_min_this_txg;
143	uint64_t scn_gt_max_this_txg;
144	uint64_t scn_ddt_contained_this_txg;
145	uint64_t scn_objsets_visited_this_txg;
146	uint64_t scn_avg_seg_size_this_txg;
147	uint64_t scn_segs_this_txg;
148	uint64_t scn_avg_zio_size_this_txg;
149	uint64_t scn_zios_this_txg;
150
151	/* members needed for syncing scan status to disk */
152	dsl_scan_phys_t scn_phys;	/* on disk representation of scan */
153	dsl_scan_phys_t scn_phys_cached;
154	avl_tree_t scn_queue;		/* queue of datasets to scan */
155	uint64_t scn_bytes_pending;	/* outstanding data to issue */
156} dsl_scan_t;
157
158typedef struct dsl_scan_io_queue dsl_scan_io_queue_t;
159
160void scan_init(void);
161void scan_fini(void);
162int dsl_scan_init(struct dsl_pool *dp, uint64_t txg);
163void dsl_scan_fini(struct dsl_pool *dp);
164void dsl_scan_sync(struct dsl_pool *, dmu_tx_t *);
165int dsl_scan_cancel(struct dsl_pool *);
166int dsl_scan(struct dsl_pool *, pool_scan_func_t);
167boolean_t dsl_scan_scrubbing(const struct dsl_pool *dp);
168int dsl_scrub_set_pause_resume(const struct dsl_pool *dp, pool_scrub_cmd_t cmd);
169void dsl_resilver_restart(struct dsl_pool *, uint64_t txg);
170boolean_t dsl_scan_resilvering(struct dsl_pool *dp);
171boolean_t dsl_dataset_unstable(struct dsl_dataset *ds);
172void dsl_scan_ddt_entry(dsl_scan_t *scn, enum zio_checksum checksum,
173    ddt_entry_t *dde, dmu_tx_t *tx);
174void dsl_scan_ds_destroyed(struct dsl_dataset *ds, struct dmu_tx *tx);
175void dsl_scan_ds_snapshotted(struct dsl_dataset *ds, struct dmu_tx *tx);
176void dsl_scan_ds_clone_swapped(struct dsl_dataset *ds1, struct dsl_dataset *ds2,
177    struct dmu_tx *tx);
178boolean_t dsl_scan_active(dsl_scan_t *scn);
179boolean_t dsl_scan_is_paused_scrub(const dsl_scan_t *scn);
180void dsl_scan_freed(spa_t *spa, const blkptr_t *bp);
181void dsl_scan_io_queue_destroy(dsl_scan_io_queue_t *queue);
182void dsl_scan_io_queue_vdev_xfer(vdev_t *svd, vdev_t *tvd);
183
184#ifdef	__cplusplus
185}
186#endif
187
188#endif /* _SYS_DSL_SCAN_H */
189