xref: /kernel/linux/linux-5.10/fs/xfs/scrub/health.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2019 Oracle.  All Rights Reserved.
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_btree.h"
11#include "xfs_sb.h"
12#include "xfs_health.h"
13#include "scrub/scrub.h"
14#include "scrub/health.h"
15
16/*
17 * Scrub and In-Core Filesystem Health Assessments
18 * ===============================================
19 *
20 * Online scrub and repair have the time and the ability to perform stronger
21 * checks than we can do from the metadata verifiers, because they can
22 * cross-reference records between data structures.  Therefore, scrub is in a
23 * good position to update the online filesystem health assessments to reflect
24 * the good/bad state of the data structure.
25 *
26 * We therefore extend scrub in the following ways to achieve this:
27 *
28 * 1. Create a "sick_mask" field in the scrub context.  When we're setting up a
29 * scrub call, set this to the default XFS_SICK_* flag(s) for the selected
30 * scrub type (call it A).  Scrub and repair functions can override the default
31 * sick_mask value if they choose.
32 *
33 * 2. If the scrubber returns a runtime error code, we exit making no changes
34 * to the incore sick state.
35 *
36 * 3. If the scrubber finds that A is clean, use sick_mask to clear the incore
37 * sick flags before exiting.
38 *
39 * 4. If the scrubber finds that A is corrupt, use sick_mask to set the incore
40 * sick flags.  If the user didn't want to repair then we exit, leaving the
41 * metadata structure unfixed and the sick flag set.
42 *
43 * 5. Now we know that A is corrupt and the user wants to repair, so run the
44 * repairer.  If the repairer returns an error code, we exit with that error
45 * code, having made no further changes to the incore sick state.
46 *
47 * 6. If repair rebuilds A correctly and the subsequent re-scrub of A is clean,
48 * use sick_mask to clear the incore sick flags.  This should have the effect
49 * that A is no longer marked sick.
50 *
51 * 7. If repair rebuilds A incorrectly, the re-scrub will find it corrupt and
52 * use sick_mask to set the incore sick flags.  This should have no externally
53 * visible effect since we already set them in step (4).
54 *
55 * There are some complications to this story, however.  For certain types of
56 * complementary metadata indices (e.g. inobt/finobt), it is easier to rebuild
57 * both structures at the same time.  The following principles apply to this
58 * type of repair strategy:
59 *
60 * 8. Any repair function that rebuilds multiple structures should update
61 * sick_mask_visible to reflect whatever other structures are rebuilt, and
62 * verify that all the rebuilt structures can pass a scrub check.  The outcomes
63 * of 5-7 still apply, but with a sick_mask that covers everything being
64 * rebuilt.
65 */
66
67/* Map our scrub type to a sick mask and a set of health update functions. */
68
69enum xchk_health_group {
70	XHG_FS = 1,
71	XHG_RT,
72	XHG_AG,
73	XHG_INO,
74};
75
76struct xchk_health_map {
77	enum xchk_health_group	group;
78	unsigned int		sick_mask;
79};
80
81static const struct xchk_health_map type_to_health_flag[XFS_SCRUB_TYPE_NR] = {
82	[XFS_SCRUB_TYPE_SB]		= { XHG_AG,  XFS_SICK_AG_SB },
83	[XFS_SCRUB_TYPE_AGF]		= { XHG_AG,  XFS_SICK_AG_AGF },
84	[XFS_SCRUB_TYPE_AGFL]		= { XHG_AG,  XFS_SICK_AG_AGFL },
85	[XFS_SCRUB_TYPE_AGI]		= { XHG_AG,  XFS_SICK_AG_AGI },
86	[XFS_SCRUB_TYPE_BNOBT]		= { XHG_AG,  XFS_SICK_AG_BNOBT },
87	[XFS_SCRUB_TYPE_CNTBT]		= { XHG_AG,  XFS_SICK_AG_CNTBT },
88	[XFS_SCRUB_TYPE_INOBT]		= { XHG_AG,  XFS_SICK_AG_INOBT },
89	[XFS_SCRUB_TYPE_FINOBT]		= { XHG_AG,  XFS_SICK_AG_FINOBT },
90	[XFS_SCRUB_TYPE_RMAPBT]		= { XHG_AG,  XFS_SICK_AG_RMAPBT },
91	[XFS_SCRUB_TYPE_REFCNTBT]	= { XHG_AG,  XFS_SICK_AG_REFCNTBT },
92	[XFS_SCRUB_TYPE_INODE]		= { XHG_INO, XFS_SICK_INO_CORE },
93	[XFS_SCRUB_TYPE_BMBTD]		= { XHG_INO, XFS_SICK_INO_BMBTD },
94	[XFS_SCRUB_TYPE_BMBTA]		= { XHG_INO, XFS_SICK_INO_BMBTA },
95	[XFS_SCRUB_TYPE_BMBTC]		= { XHG_INO, XFS_SICK_INO_BMBTC },
96	[XFS_SCRUB_TYPE_DIR]		= { XHG_INO, XFS_SICK_INO_DIR },
97	[XFS_SCRUB_TYPE_XATTR]		= { XHG_INO, XFS_SICK_INO_XATTR },
98	[XFS_SCRUB_TYPE_SYMLINK]	= { XHG_INO, XFS_SICK_INO_SYMLINK },
99	[XFS_SCRUB_TYPE_PARENT]		= { XHG_INO, XFS_SICK_INO_PARENT },
100	[XFS_SCRUB_TYPE_RTBITMAP]	= { XHG_RT,  XFS_SICK_RT_BITMAP },
101	[XFS_SCRUB_TYPE_RTSUM]		= { XHG_RT,  XFS_SICK_RT_SUMMARY },
102	[XFS_SCRUB_TYPE_UQUOTA]		= { XHG_FS,  XFS_SICK_FS_UQUOTA },
103	[XFS_SCRUB_TYPE_GQUOTA]		= { XHG_FS,  XFS_SICK_FS_GQUOTA },
104	[XFS_SCRUB_TYPE_PQUOTA]		= { XHG_FS,  XFS_SICK_FS_PQUOTA },
105	[XFS_SCRUB_TYPE_FSCOUNTERS]	= { XHG_FS,  XFS_SICK_FS_COUNTERS },
106};
107
108/* Return the health status mask for this scrub type. */
109unsigned int
110xchk_health_mask_for_scrub_type(
111	__u32			scrub_type)
112{
113	return type_to_health_flag[scrub_type].sick_mask;
114}
115
116/*
117 * Update filesystem health assessments based on what we found and did.
118 *
119 * If the scrubber finds errors, we mark sick whatever's mentioned in
120 * sick_mask, no matter whether this is a first scan or an
121 * evaluation of repair effectiveness.
122 *
123 * Otherwise, no direct corruption was found, so mark whatever's in
124 * sick_mask as healthy.
125 */
126void
127xchk_update_health(
128	struct xfs_scrub	*sc)
129{
130	struct xfs_perag	*pag;
131	bool			bad;
132
133	if (!sc->sick_mask)
134		return;
135
136	bad = (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT);
137	switch (type_to_health_flag[sc->sm->sm_type].group) {
138	case XHG_AG:
139		pag = xfs_perag_get(sc->mp, sc->sm->sm_agno);
140		if (bad)
141			xfs_ag_mark_sick(pag, sc->sick_mask);
142		else
143			xfs_ag_mark_healthy(pag, sc->sick_mask);
144		xfs_perag_put(pag);
145		break;
146	case XHG_INO:
147		if (!sc->ip)
148			return;
149		if (bad)
150			xfs_inode_mark_sick(sc->ip, sc->sick_mask);
151		else
152			xfs_inode_mark_healthy(sc->ip, sc->sick_mask);
153		break;
154	case XHG_FS:
155		if (bad)
156			xfs_fs_mark_sick(sc->mp, sc->sick_mask);
157		else
158			xfs_fs_mark_healthy(sc->mp, sc->sick_mask);
159		break;
160	case XHG_RT:
161		if (bad)
162			xfs_rt_mark_sick(sc->mp, sc->sick_mask);
163		else
164			xfs_rt_mark_healthy(sc->mp, sc->sick_mask);
165		break;
166	default:
167		ASSERT(0);
168		break;
169	}
170}
171
172/* Is the given per-AG btree healthy enough for scanning? */
173bool
174xchk_ag_btree_healthy_enough(
175	struct xfs_scrub	*sc,
176	struct xfs_perag	*pag,
177	xfs_btnum_t		btnum)
178{
179	unsigned int		mask = 0;
180
181	/*
182	 * We always want the cursor if it's the same type as whatever we're
183	 * scrubbing, even if we already know the structure is corrupt.
184	 *
185	 * Otherwise, we're only interested in the btree for cross-referencing.
186	 * If we know the btree is bad then don't bother, just set XFAIL.
187	 */
188	switch (btnum) {
189	case XFS_BTNUM_BNO:
190		if (sc->sm->sm_type == XFS_SCRUB_TYPE_BNOBT)
191			return true;
192		mask = XFS_SICK_AG_BNOBT;
193		break;
194	case XFS_BTNUM_CNT:
195		if (sc->sm->sm_type == XFS_SCRUB_TYPE_CNTBT)
196			return true;
197		mask = XFS_SICK_AG_CNTBT;
198		break;
199	case XFS_BTNUM_INO:
200		if (sc->sm->sm_type == XFS_SCRUB_TYPE_INOBT)
201			return true;
202		mask = XFS_SICK_AG_INOBT;
203		break;
204	case XFS_BTNUM_FINO:
205		if (sc->sm->sm_type == XFS_SCRUB_TYPE_FINOBT)
206			return true;
207		mask = XFS_SICK_AG_FINOBT;
208		break;
209	case XFS_BTNUM_RMAP:
210		if (sc->sm->sm_type == XFS_SCRUB_TYPE_RMAPBT)
211			return true;
212		mask = XFS_SICK_AG_RMAPBT;
213		break;
214	case XFS_BTNUM_REFC:
215		if (sc->sm->sm_type == XFS_SCRUB_TYPE_REFCNTBT)
216			return true;
217		mask = XFS_SICK_AG_REFCNTBT;
218		break;
219	default:
220		ASSERT(0);
221		return true;
222	}
223
224	if (xfs_ag_has_sickness(pag, mask)) {
225		sc->sm->sm_flags |= XFS_SCRUB_OFLAG_XFAIL;
226		return false;
227	}
228
229	return true;
230}
231