xref: /linux/fs/xfs/scrub/alloc.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2017-2023 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <djwong@kernel.org>
5  */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_log_format.h"
13 #include "xfs_trans.h"
14 #include "xfs_btree.h"
15 #include "xfs_alloc.h"
16 #include "xfs_rmap.h"
17 #include "xfs_ag.h"
18 #include "scrub/scrub.h"
19 #include "scrub/common.h"
20 #include "scrub/btree.h"
21 #include "scrub/repair.h"
22 
23 /*
24  * Set us up to scrub free space btrees.
25  */
26 int
27 xchk_setup_ag_allocbt(
28 	struct xfs_scrub	*sc)
29 {
30 	int			error;
31 
32 	if (xchk_need_intent_drain(sc))
33 		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
34 
35 	error = xchk_setup_ag_btree(sc, false);
36 	if (error)
37 		return error;
38 
39 	if (xchk_could_repair(sc))
40 		return xrep_setup_ag_allocbt(sc);
41 
42 	return 0;
43 }
44 
45 /* Free space btree scrubber. */
46 
47 struct xchk_alloc {
48 	/* Previous free space extent. */
49 	struct xfs_alloc_rec_incore	prev;
50 };
51 
52 /*
53  * Ensure there's a corresponding cntbt/bnobt record matching this
54  * bnobt/cntbt record, respectively.
55  */
56 STATIC void
57 xchk_allocbt_xref_other(
58 	struct xfs_scrub	*sc,
59 	xfs_agblock_t		agbno,
60 	xfs_extlen_t		len)
61 {
62 	struct xfs_btree_cur	**pcur;
63 	xfs_agblock_t		fbno;
64 	xfs_extlen_t		flen;
65 	int			has_otherrec;
66 	int			error;
67 
68 	if (sc->sm->sm_type == XFS_SCRUB_TYPE_BNOBT)
69 		pcur = &sc->sa.cnt_cur;
70 	else
71 		pcur = &sc->sa.bno_cur;
72 	if (!*pcur || xchk_skip_xref(sc->sm))
73 		return;
74 
75 	error = xfs_alloc_lookup_le(*pcur, agbno, len, &has_otherrec);
76 	if (!xchk_should_check_xref(sc, &error, pcur))
77 		return;
78 	if (!has_otherrec) {
79 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
80 		return;
81 	}
82 
83 	error = xfs_alloc_get_rec(*pcur, &fbno, &flen, &has_otherrec);
84 	if (!xchk_should_check_xref(sc, &error, pcur))
85 		return;
86 	if (!has_otherrec) {
87 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
88 		return;
89 	}
90 
91 	if (fbno != agbno || flen != len)
92 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
93 }
94 
95 /* Cross-reference with the other btrees. */
96 STATIC void
97 xchk_allocbt_xref(
98 	struct xfs_scrub	*sc,
99 	const struct xfs_alloc_rec_incore *irec)
100 {
101 	xfs_agblock_t		agbno = irec->ar_startblock;
102 	xfs_extlen_t		len = irec->ar_blockcount;
103 
104 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
105 		return;
106 
107 	xchk_allocbt_xref_other(sc, agbno, len);
108 	xchk_xref_is_not_inode_chunk(sc, agbno, len);
109 	xchk_xref_has_no_owner(sc, agbno, len);
110 	xchk_xref_is_not_shared(sc, agbno, len);
111 	xchk_xref_is_not_cow_staging(sc, agbno, len);
112 }
113 
114 /* Flag failures for records that could be merged. */
115 STATIC void
116 xchk_allocbt_mergeable(
117 	struct xchk_btree	*bs,
118 	struct xchk_alloc	*ca,
119 	const struct xfs_alloc_rec_incore *irec)
120 {
121 	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
122 		return;
123 
124 	if (ca->prev.ar_blockcount > 0 &&
125 	    ca->prev.ar_startblock + ca->prev.ar_blockcount == irec->ar_startblock &&
126 	    ca->prev.ar_blockcount + irec->ar_blockcount < (uint32_t)~0U)
127 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
128 
129 	memcpy(&ca->prev, irec, sizeof(*irec));
130 }
131 
132 /* Scrub a bnobt/cntbt record. */
133 STATIC int
134 xchk_allocbt_rec(
135 	struct xchk_btree		*bs,
136 	const union xfs_btree_rec	*rec)
137 {
138 	struct xfs_alloc_rec_incore	irec;
139 	struct xchk_alloc	*ca = bs->private;
140 
141 	xfs_alloc_btrec_to_irec(rec, &irec);
142 	if (xfs_alloc_check_irec(bs->cur->bc_ag.pag, &irec) != NULL) {
143 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
144 		return 0;
145 	}
146 
147 	xchk_allocbt_mergeable(bs, ca, &irec);
148 	xchk_allocbt_xref(bs->sc, &irec);
149 
150 	return 0;
151 }
152 
153 /* Scrub one of the freespace btrees for some AG. */
154 int
155 xchk_allocbt(
156 	struct xfs_scrub	*sc)
157 {
158 	struct xchk_alloc	ca = { };
159 	struct xfs_btree_cur	*cur;
160 
161 	switch (sc->sm->sm_type) {
162 	case XFS_SCRUB_TYPE_BNOBT:
163 		cur = sc->sa.bno_cur;
164 		break;
165 	case XFS_SCRUB_TYPE_CNTBT:
166 		cur = sc->sa.cnt_cur;
167 		break;
168 	default:
169 		ASSERT(0);
170 		return -EIO;
171 	}
172 
173 	return xchk_btree(sc, cur, xchk_allocbt_rec, &XFS_RMAP_OINFO_AG, &ca);
174 }
175 
176 /* xref check that the extent is not free */
177 void
178 xchk_xref_is_used_space(
179 	struct xfs_scrub	*sc,
180 	xfs_agblock_t		agbno,
181 	xfs_extlen_t		len)
182 {
183 	enum xbtree_recpacking	outcome;
184 	int			error;
185 
186 	if (!sc->sa.bno_cur || xchk_skip_xref(sc->sm))
187 		return;
188 
189 	error = xfs_alloc_has_records(sc->sa.bno_cur, agbno, len, &outcome);
190 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
191 		return;
192 	if (outcome != XBTREE_RECPACKING_EMPTY)
193 		xchk_btree_xref_set_corrupt(sc, sc->sa.bno_cur, 0);
194 }
195