xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/dsl_scan.h (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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, 2019, Datto Inc. All rights reserved.
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
36 extern "C" {
37 #endif
38 
39 struct objset;
40 struct dsl_dir;
41 struct dsl_dataset;
42 struct dsl_pool;
43 struct dmu_tx;
44 
45 /*
46  * All members of this structure must be uint64_t, for byteswap
47  * purposes.
48  */
49 typedef 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 
72 typedef 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  */
109 typedef 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 
158 typedef struct dsl_scan_io_queue dsl_scan_io_queue_t;
159 
160 void scan_init(void);
161 void scan_fini(void);
162 int dsl_scan_init(struct dsl_pool *dp, uint64_t txg);
163 void dsl_scan_fini(struct dsl_pool *dp);
164 void dsl_scan_sync(struct dsl_pool *, dmu_tx_t *);
165 int dsl_scan_cancel(struct dsl_pool *);
166 int dsl_scan(struct dsl_pool *, pool_scan_func_t);
167 void dsl_scan_assess_vdev(struct dsl_pool *dp, vdev_t *vd);
168 boolean_t dsl_scan_scrubbing(const struct dsl_pool *dp);
169 int dsl_scrub_set_pause_resume(const struct dsl_pool *dp, pool_scrub_cmd_t cmd);
170 void dsl_scan_restart_resilver(struct dsl_pool *, uint64_t txg);
171 boolean_t dsl_scan_resilvering(struct dsl_pool *dp);
172 boolean_t dsl_scan_resilver_scheduled(struct dsl_pool *dp);
173 boolean_t dsl_dataset_unstable(struct dsl_dataset *ds);
174 void dsl_scan_ddt_entry(dsl_scan_t *scn, enum zio_checksum checksum,
175     ddt_entry_t *dde, dmu_tx_t *tx);
176 void dsl_scan_ds_destroyed(struct dsl_dataset *ds, struct dmu_tx *tx);
177 void dsl_scan_ds_snapshotted(struct dsl_dataset *ds, struct dmu_tx *tx);
178 void dsl_scan_ds_clone_swapped(struct dsl_dataset *ds1, struct dsl_dataset *ds2,
179     struct dmu_tx *tx);
180 boolean_t dsl_scan_active(dsl_scan_t *scn);
181 boolean_t dsl_scan_is_paused_scrub(const dsl_scan_t *scn);
182 void dsl_scan_freed(spa_t *spa, const blkptr_t *bp);
183 void dsl_scan_io_queue_destroy(dsl_scan_io_queue_t *queue);
184 void dsl_scan_io_queue_vdev_xfer(vdev_t *svd, vdev_t *tvd);
185 
186 #ifdef	__cplusplus
187 }
188 #endif
189 
190 #endif /* _SYS_DSL_SCAN_H */
191