summaryrefslogtreecommitdiff
path: root/fs/xfs/scrub/health.c
blob: 9020a6bef7f14ccf97e12f7a64fda26daf5a58a5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2019-2023 Oracle.  All Rights Reserved.
 * Author: Darrick J. Wong <djwong@kernel.org>
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_btree.h"
#include "xfs_ag.h"
#include "xfs_health.h"
#include "scrub/scrub.h"
#include "scrub/health.h"
#include "scrub/common.h"

/*
 * Scrub and In-Core Filesystem Health Assessments
 * ===============================================
 *
 * Online scrub and repair have the time and the ability to perform stronger
 * checks than we can do from the metadata verifiers, because they can
 * cross-reference records between data structures.  Therefore, scrub is in a
 * good position to update the online filesystem health assessments to reflect
 * the good/bad state of the data structure.
 *
 * We therefore extend scrub in the following ways to achieve this:
 *
 * 1. Create a "sick_mask" field in the scrub context.  When we're setting up a
 * scrub call, set this to the default XFS_SICK_* flag(s) for the selected
 * scrub type (call it A).  Scrub and repair functions can override the default
 * sick_mask value if they choose.
 *
 * 2. If the scrubber returns a runtime error code, we exit making no changes
 * to the incore sick state.
 *
 * 3. If the scrubber finds that A is clean, use sick_mask to clear the incore
 * sick flags before exiting.
 *
 * 4. If the scrubber finds that A is corrupt, use sick_mask to set the incore
 * sick flags.  If the user didn't want to repair then we exit, leaving the
 * metadata structure unfixed and the sick flag set.
 *
 * 5. Now we know that A is corrupt and the user wants to repair, so run the
 * repairer.  If the repairer returns an error code, we exit with that error
 * code, having made no further changes to the incore sick state.
 *
 * 6. If repair rebuilds A correctly and the subsequent re-scrub of A is clean,
 * use sick_mask to clear the incore sick flags.  This should have the effect
 * that A is no longer marked sick.
 *
 * 7. If repair rebuilds A incorrectly, the re-scrub will find it corrupt and
 * use sick_mask to set the incore sick flags.  This should have no externally
 * visible effect since we already set them in step (4).
 *
 * There are some complications to this story, however.  For certain types of
 * complementary metadata indices (e.g. inobt/finobt), it is easier to rebuild
 * both structures at the same time.  The following principles apply to this
 * type of repair strategy:
 *
 * 8. Any repair function that rebuilds multiple structures should update
 * sick_mask_visible to reflect whatever other structures are rebuilt, and
 * verify that all the rebuilt structures can pass a scrub check.  The outcomes
 * of 5-7 still apply, but with a sick_mask that covers everything being
 * rebuilt.
 */

/* Map our scrub type to a sick mask and a set of health update functions. */

enum xchk_health_group {
	XHG_FS = 1,
	XHG_RT,
	XHG_AG,
	XHG_INO,
};

struct xchk_health_map {
	enum xchk_health_group	group;
	unsigned int		sick_mask;
};

static const struct xchk_health_map type_to_health_flag[XFS_SCRUB_TYPE_NR] = {
	[XFS_SCRUB_TYPE_SB]		= { XHG_AG,  XFS_SICK_AG_SB },
	[XFS_SCRUB_TYPE_AGF]		= { XHG_AG,  XFS_SICK_AG_AGF },
	[XFS_SCRUB_TYPE_AGFL]		= { XHG_AG,  XFS_SICK_AG_AGFL },
	[XFS_SCRUB_TYPE_AGI]		= { XHG_AG,  XFS_SICK_AG_AGI },
	[XFS_SCRUB_TYPE_BNOBT]		= { XHG_AG,  XFS_SICK_AG_BNOBT },
	[XFS_SCRUB_TYPE_CNTBT]		= { XHG_AG,  XFS_SICK_AG_CNTBT },
	[XFS_SCRUB_TYPE_INOBT]		= { XHG_AG,  XFS_SICK_AG_INOBT },
	[XFS_SCRUB_TYPE_FINOBT]		= { XHG_AG,  XFS_SICK_AG_FINOBT },
	[XFS_SCRUB_TYPE_RMAPBT]		= { XHG_AG,  XFS_SICK_AG_RMAPBT },
	[XFS_SCRUB_TYPE_REFCNTBT]	= { XHG_AG,  XFS_SICK_AG_REFCNTBT },
	[XFS_SCRUB_TYPE_INODE]		= { XHG_INO, XFS_SICK_INO_CORE },
	[XFS_SCRUB_TYPE_BMBTD]		= { XHG_INO, XFS_SICK_INO_BMBTD },
	[XFS_SCRUB_TYPE_BMBTA]		= { XHG_INO, XFS_SICK_INO_BMBTA },
	[XFS_SCRUB_TYPE_BMBTC]		= { XHG_INO, XFS_SICK_INO_BMBTC },
	[XFS_SCRUB_TYPE_DIR]		= { XHG_INO, XFS_SICK_INO_DIR },
	[XFS_SCRUB_TYPE_XATTR]		= { XHG_INO, XFS_SICK_INO_XATTR },
	[XFS_SCRUB_TYPE_SYMLINK]	= { XHG_INO, XFS_SICK_INO_SYMLINK },
	[XFS_SCRUB_TYPE_PARENT]		= { XHG_INO, XFS_SICK_INO_PARENT },
	[XFS_SCRUB_TYPE_RTBITMAP]	= { XHG_RT,  XFS_SICK_RT_BITMAP },
	[XFS_SCRUB_TYPE_RTSUM]		= { XHG_RT,  XFS_SICK_RT_SUMMARY },
	[XFS_SCRUB_TYPE_UQUOTA]		= { XHG_FS,  XFS_SICK_FS_UQUOTA },
	[XFS_SCRUB_TYPE_GQUOTA]		= { XHG_FS,  XFS_SICK_FS_GQUOTA },
	[XFS_SCRUB_TYPE_PQUOTA]		= { XHG_FS,  XFS_SICK_FS_PQUOTA },
	[XFS_SCRUB_TYPE_FSCOUNTERS]	= { XHG_FS,  XFS_SICK_FS_COUNTERS },
	[XFS_SCRUB_TYPE_QUOTACHECK]	= { XHG_FS,  XFS_SICK_FS_QUOTACHECK },
	[XFS_SCRUB_TYPE_NLINKS]		= { XHG_FS,  XFS_SICK_FS_NLINKS },
};

/* Return the health status mask for this scrub type. */
unsigned int
xchk_health_mask_for_scrub_type(
	__u32			scrub_type)
{
	return type_to_health_flag[scrub_type].sick_mask;
}

/*
 * If the scrub state is clean, add @mask to the scrub sick mask to clear
 * additional sick flags from the metadata object's sick state.
 */
void
xchk_mark_healthy_if_clean(
	struct xfs_scrub	*sc,
	unsigned int		mask)
{
	if (!(sc->sm->sm_flags & (XFS_SCRUB_OFLAG_CORRUPT |
				  XFS_SCRUB_OFLAG_XCORRUPT)))
		sc->sick_mask |= mask;
}

/*
 * If we're scrubbing a piece of file metadata for the first time, does it look
 * like it has been zapped?  Skip the check if we just repaired the metadata
 * and are revalidating it.
 */
bool
xchk_file_looks_zapped(
	struct xfs_scrub	*sc,
	unsigned int		mask)
{
	ASSERT((mask & ~XFS_SICK_INO_ZAPPED) == 0);

	if (sc->flags & XREP_ALREADY_FIXED)
		return false;

	return xfs_inode_has_sickness(sc->ip, mask);
}

/*
 * Scrub gave the filesystem a clean bill of health, so clear all the indirect
 * markers of past problems (at least for the fs and ags) so that we can be
 * healthy again.
 */
STATIC void
xchk_mark_all_healthy(
	struct xfs_mount	*mp)
{
	struct xfs_perag	*pag;
	xfs_agnumber_t		agno;

	xfs_fs_mark_healthy(mp, XFS_SICK_FS_INDIRECT);
	xfs_rt_mark_healthy(mp, XFS_SICK_RT_INDIRECT);
	for_each_perag(mp, agno, pag)
		xfs_ag_mark_healthy(pag, XFS_SICK_AG_INDIRECT);
}

/*
 * Update filesystem health assessments based on what we found and did.
 *
 * If the scrubber finds errors, we mark sick whatever's mentioned in
 * sick_mask, no matter whether this is a first scan or an
 * evaluation of repair effectiveness.
 *
 * Otherwise, no direct corruption was found, so mark whatever's in
 * sick_mask as healthy.
 */
void
xchk_update_health(
	struct xfs_scrub	*sc)
{
	struct xfs_perag	*pag;
	bool			bad;

	/*
	 * The HEALTHY scrub type is a request from userspace to clear all the
	 * indirect flags after a clean scan of the entire filesystem.  As such
	 * there's no sick flag defined for it, so we branch here ahead of the
	 * mask check.
	 */
	if (sc->sm->sm_type == XFS_SCRUB_TYPE_HEALTHY &&
	    !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
		xchk_mark_all_healthy(sc->mp);
		return;
	}

	if (!sc->sick_mask)
		return;

	bad = (sc->sm->sm_flags & (XFS_SCRUB_OFLAG_CORRUPT |
				   XFS_SCRUB_OFLAG_XCORRUPT));
	switch (type_to_health_flag[sc->sm->sm_type].group) {
	case XHG_AG:
		pag = xfs_perag_get(sc->mp, sc->sm->sm_agno);
		if (bad)
			xfs_ag_mark_corrupt(pag, sc->sick_mask);
		else
			xfs_ag_mark_healthy(pag, sc->sick_mask);
		xfs_perag_put(pag);
		break;
	case XHG_INO:
		if (!sc->ip)
			return;
		if (bad) {
			unsigned int	mask = sc->sick_mask;

			/*
			 * If we're coming in for repairs then we don't want
			 * sickness flags to propagate to the incore health
			 * status if the inode gets inactivated before we can
			 * fix it.
			 */
			if (sc->sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR)
				mask |= XFS_SICK_INO_FORGET;
			xfs_inode_mark_corrupt(sc->ip, mask);
		} else
			xfs_inode_mark_healthy(sc->ip, sc->sick_mask);
		break;
	case XHG_FS:
		if (bad)
			xfs_fs_mark_corrupt(sc->mp, sc->sick_mask);
		else
			xfs_fs_mark_healthy(sc->mp, sc->sick_mask);
		break;
	case XHG_RT:
		if (bad)
			xfs_rt_mark_corrupt(sc->mp, sc->sick_mask);
		else
			xfs_rt_mark_healthy(sc->mp, sc->sick_mask);
		break;
	default:
		ASSERT(0);
		break;
	}
}

/* Is the given per-AG btree healthy enough for scanning? */
void
xchk_ag_btree_del_cursor_if_sick(
	struct xfs_scrub	*sc,
	struct xfs_btree_cur	**curp,
	unsigned int		sm_type)
{
	unsigned int		mask = (*curp)->bc_ops->sick_mask;

	/*
	 * We always want the cursor if it's the same type as whatever we're
	 * scrubbing, even if we already know the structure is corrupt.
	 *
	 * Otherwise, we're only interested in the btree for cross-referencing.
	 * If we know the btree is bad then don't bother, just set XFAIL.
	 */
	if (sc->sm->sm_type == sm_type)
		return;

	/*
	 * If we just repaired some AG metadata, sc->sick_mask will reflect all
	 * the per-AG metadata types that were repaired.  Exclude these from
	 * the filesystem health query because we have not yet updated the
	 * health status and we want everything to be scanned.
	 */
	if ((sc->flags & XREP_ALREADY_FIXED) &&
	    type_to_health_flag[sc->sm->sm_type].group == XHG_AG)
		mask &= ~sc->sick_mask;

	if (xfs_ag_has_sickness((*curp)->bc_ag.pag, mask)) {
		sc->sm->sm_flags |= XFS_SCRUB_OFLAG_XFAIL;
		xfs_btree_del_cursor(*curp, XFS_BTREE_NOERROR);
		*curp = NULL;
	}
}

/*
 * Quick scan to double-check that there isn't any evidence of lingering
 * primary health problems.  If we're still clear, then the health update will
 * take care of clearing the indirect evidence.
 */
int
xchk_health_record(
	struct xfs_scrub	*sc)
{
	struct xfs_mount	*mp = sc->mp;
	struct xfs_perag	*pag;
	xfs_agnumber_t		agno;

	unsigned int		sick;
	unsigned int		checked;

	xfs_fs_measure_sickness(mp, &sick, &checked);
	if (sick & XFS_SICK_FS_PRIMARY)
		xchk_set_corrupt(sc);

	xfs_rt_measure_sickness(mp, &sick, &checked);
	if (sick & XFS_SICK_RT_PRIMARY)
		xchk_set_corrupt(sc);

	for_each_perag(mp, agno, pag) {
		xfs_ag_measure_sickness(pag, &sick, &checked);
		if (sick & XFS_SICK_AG_PRIMARY)
			xchk_set_corrupt(sc);
	}

	return 0;
}