xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/dsl_scan.h (revision 2a613b5974ae49c8b068a3998ff554f8c6f0f593)
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
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 /*
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_suspending -	a scan that cannot be completed in a single txg or
88  *			has exceeded its allotted time will need to suspend.
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_suspending;
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 	uint64_t  scn_async_block_min_time_ms;
121 
122 	/* for debugging / information */
123 	uint64_t scn_visited_this_txg;
124 
125 	dsl_scan_phys_t scn_phys;
126 } dsl_scan_t;
127 
128 int dsl_scan_init(struct dsl_pool *dp, uint64_t txg);
129 void dsl_scan_fini(struct dsl_pool *dp);
130 void dsl_scan_sync(struct dsl_pool *, dmu_tx_t *);
131 int dsl_scan_cancel(struct dsl_pool *);
132 int dsl_scan(struct dsl_pool *, pool_scan_func_t);
133 boolean_t dsl_scan_scrubbing(const struct dsl_pool *dp);
134 int dsl_scrub_set_pause_resume(const struct dsl_pool *dp, pool_scrub_cmd_t cmd);
135 void dsl_resilver_restart(struct dsl_pool *, uint64_t txg);
136 boolean_t dsl_scan_resilvering(struct dsl_pool *dp);
137 boolean_t dsl_dataset_unstable(struct dsl_dataset *ds);
138 void dsl_scan_ddt_entry(dsl_scan_t *scn, enum zio_checksum checksum,
139     ddt_entry_t *dde, dmu_tx_t *tx);
140 void dsl_scan_ds_destroyed(struct dsl_dataset *ds, struct dmu_tx *tx);
141 void dsl_scan_ds_snapshotted(struct dsl_dataset *ds, struct dmu_tx *tx);
142 void dsl_scan_ds_clone_swapped(struct dsl_dataset *ds1, struct dsl_dataset *ds2,
143     struct dmu_tx *tx);
144 boolean_t dsl_scan_active(dsl_scan_t *scn);
145 boolean_t dsl_scan_is_paused_scrub(const dsl_scan_t *scn);
146 
147 #ifdef	__cplusplus
148 }
149 #endif
150 
151 #endif /* _SYS_DSL_SCAN_H */
152