xref: /openbmc/linux/fs/xfs/scrub/alloc.c (revision 9aa2cba7)
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_btree.h"
13 #include "xfs_alloc.h"
14 #include "xfs_rmap.h"
15 #include "scrub/scrub.h"
16 #include "scrub/common.h"
17 #include "scrub/btree.h"
18 #include "xfs_ag.h"
19 
20 /*
21  * Set us up to scrub free space btrees.
22  */
23 int
24 xchk_setup_ag_allocbt(
25 	struct xfs_scrub	*sc)
26 {
27 	if (xchk_need_intent_drain(sc))
28 		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
29 
30 	return xchk_setup_ag_btree(sc, false);
31 }
32 
33 /* Free space btree scrubber. */
34 
35 struct xchk_alloc {
36 	/* Previous free space extent. */
37 	struct xfs_alloc_rec_incore	prev;
38 };
39 
40 /*
41  * Ensure there's a corresponding cntbt/bnobt record matching this
42  * bnobt/cntbt record, respectively.
43  */
44 STATIC void
45 xchk_allocbt_xref_other(
46 	struct xfs_scrub	*sc,
47 	xfs_agblock_t		agbno,
48 	xfs_extlen_t		len)
49 {
50 	struct xfs_btree_cur	**pcur;
51 	xfs_agblock_t		fbno;
52 	xfs_extlen_t		flen;
53 	int			has_otherrec;
54 	int			error;
55 
56 	if (sc->sm->sm_type == XFS_SCRUB_TYPE_BNOBT)
57 		pcur = &sc->sa.cnt_cur;
58 	else
59 		pcur = &sc->sa.bno_cur;
60 	if (!*pcur || xchk_skip_xref(sc->sm))
61 		return;
62 
63 	error = xfs_alloc_lookup_le(*pcur, agbno, len, &has_otherrec);
64 	if (!xchk_should_check_xref(sc, &error, pcur))
65 		return;
66 	if (!has_otherrec) {
67 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
68 		return;
69 	}
70 
71 	error = xfs_alloc_get_rec(*pcur, &fbno, &flen, &has_otherrec);
72 	if (!xchk_should_check_xref(sc, &error, pcur))
73 		return;
74 	if (!has_otherrec) {
75 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
76 		return;
77 	}
78 
79 	if (fbno != agbno || flen != len)
80 		xchk_btree_xref_set_corrupt(sc, *pcur, 0);
81 }
82 
83 /* Cross-reference with the other btrees. */
84 STATIC void
85 xchk_allocbt_xref(
86 	struct xfs_scrub	*sc,
87 	const struct xfs_alloc_rec_incore *irec)
88 {
89 	xfs_agblock_t		agbno = irec->ar_startblock;
90 	xfs_extlen_t		len = irec->ar_blockcount;
91 
92 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
93 		return;
94 
95 	xchk_allocbt_xref_other(sc, agbno, len);
96 	xchk_xref_is_not_inode_chunk(sc, agbno, len);
97 	xchk_xref_has_no_owner(sc, agbno, len);
98 	xchk_xref_is_not_shared(sc, agbno, len);
99 	xchk_xref_is_not_cow_staging(sc, agbno, len);
100 }
101 
102 /* Flag failures for records that could be merged. */
103 STATIC void
104 xchk_allocbt_mergeable(
105 	struct xchk_btree	*bs,
106 	struct xchk_alloc	*ca,
107 	const struct xfs_alloc_rec_incore *irec)
108 {
109 	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
110 		return;
111 
112 	if (ca->prev.ar_blockcount > 0 &&
113 	    ca->prev.ar_startblock + ca->prev.ar_blockcount == irec->ar_startblock &&
114 	    ca->prev.ar_blockcount + irec->ar_blockcount < (uint32_t)~0U)
115 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
116 
117 	memcpy(&ca->prev, irec, sizeof(*irec));
118 }
119 
120 /* Scrub a bnobt/cntbt record. */
121 STATIC int
122 xchk_allocbt_rec(
123 	struct xchk_btree		*bs,
124 	const union xfs_btree_rec	*rec)
125 {
126 	struct xfs_alloc_rec_incore	irec;
127 	struct xchk_alloc	*ca = bs->private;
128 
129 	xfs_alloc_btrec_to_irec(rec, &irec);
130 	if (xfs_alloc_check_irec(bs->cur, &irec) != NULL) {
131 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
132 		return 0;
133 	}
134 
135 	xchk_allocbt_mergeable(bs, ca, &irec);
136 	xchk_allocbt_xref(bs->sc, &irec);
137 
138 	return 0;
139 }
140 
141 /* Scrub the freespace btrees for some AG. */
142 STATIC int
143 xchk_allocbt(
144 	struct xfs_scrub	*sc,
145 	xfs_btnum_t		which)
146 {
147 	struct xchk_alloc	ca = { };
148 	struct xfs_btree_cur	*cur;
149 
150 	cur = which == XFS_BTNUM_BNO ? sc->sa.bno_cur : sc->sa.cnt_cur;
151 	return xchk_btree(sc, cur, xchk_allocbt_rec, &XFS_RMAP_OINFO_AG, &ca);
152 }
153 
154 int
155 xchk_bnobt(
156 	struct xfs_scrub	*sc)
157 {
158 	return xchk_allocbt(sc, XFS_BTNUM_BNO);
159 }
160 
161 int
162 xchk_cntbt(
163 	struct xfs_scrub	*sc)
164 {
165 	return xchk_allocbt(sc, XFS_BTNUM_CNT);
166 }
167 
168 /* xref check that the extent is not free */
169 void
170 xchk_xref_is_used_space(
171 	struct xfs_scrub	*sc,
172 	xfs_agblock_t		agbno,
173 	xfs_extlen_t		len)
174 {
175 	enum xbtree_recpacking	outcome;
176 	int			error;
177 
178 	if (!sc->sa.bno_cur || xchk_skip_xref(sc->sm))
179 		return;
180 
181 	error = xfs_alloc_has_records(sc->sa.bno_cur, agbno, len, &outcome);
182 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
183 		return;
184 	if (outcome != XBTREE_RECPACKING_EMPTY)
185 		xchk_btree_xref_set_corrupt(sc, sc->sa.bno_cur, 0);
186 }
187