xref: /linux/fs/xfs/scrub/rtrmap.c (revision 6a849bd81b69ccbda5b766cc700f0be86194e4d1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2018-2024 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_defer.h"
13 #include "xfs_btree.h"
14 #include "xfs_bit.h"
15 #include "xfs_log_format.h"
16 #include "xfs_trans.h"
17 #include "xfs_sb.h"
18 #include "xfs_rmap.h"
19 #include "xfs_rmap_btree.h"
20 #include "xfs_rtrmap_btree.h"
21 #include "xfs_inode.h"
22 #include "xfs_rtalloc.h"
23 #include "xfs_rtgroup.h"
24 #include "xfs_metafile.h"
25 #include "scrub/xfs_scrub.h"
26 #include "scrub/scrub.h"
27 #include "scrub/common.h"
28 #include "scrub/btree.h"
29 #include "scrub/trace.h"
30 #include "scrub/repair.h"
31 
32 /* Set us up with the realtime metadata locked. */
33 int
34 xchk_setup_rtrmapbt(
35 	struct xfs_scrub	*sc)
36 {
37 	int			error;
38 
39 	if (xchk_need_intent_drain(sc))
40 		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
41 
42 	if (xchk_could_repair(sc)) {
43 		error = xrep_setup_rtrmapbt(sc);
44 		if (error)
45 			return error;
46 	}
47 
48 	error = xchk_rtgroup_init(sc, sc->sm->sm_agno, &sc->sr);
49 	if (error)
50 		return error;
51 
52 	error = xchk_setup_rt(sc);
53 	if (error)
54 		return error;
55 
56 	error = xchk_install_live_inode(sc, rtg_rmap(sc->sr.rtg));
57 	if (error)
58 		return error;
59 
60 	return xchk_rtgroup_lock(sc, &sc->sr, XCHK_RTGLOCK_ALL);
61 }
62 
63 /* Realtime reverse mapping. */
64 
65 struct xchk_rtrmap {
66 	/*
67 	 * The furthest-reaching of the rmapbt records that we've already
68 	 * processed.  This enables us to detect overlapping records for space
69 	 * allocations that cannot be shared.
70 	 */
71 	struct xfs_rmap_irec	overlap_rec;
72 
73 	/*
74 	 * The previous rmapbt record, so that we can check for two records
75 	 * that could be one.
76 	 */
77 	struct xfs_rmap_irec	prev_rec;
78 };
79 
80 /* Flag failures for records that overlap but cannot. */
81 STATIC void
82 xchk_rtrmapbt_check_overlapping(
83 	struct xchk_btree		*bs,
84 	struct xchk_rtrmap		*cr,
85 	const struct xfs_rmap_irec	*irec)
86 {
87 	xfs_rtblock_t			pnext, inext;
88 
89 	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
90 		return;
91 
92 	/* No previous record? */
93 	if (cr->overlap_rec.rm_blockcount == 0)
94 		goto set_prev;
95 
96 	/* Do overlap_rec and irec overlap? */
97 	pnext = cr->overlap_rec.rm_startblock + cr->overlap_rec.rm_blockcount;
98 	if (pnext <= irec->rm_startblock)
99 		goto set_prev;
100 
101 	xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
102 
103 	/* Save whichever rmap record extends furthest. */
104 	inext = irec->rm_startblock + irec->rm_blockcount;
105 	if (pnext > inext)
106 		return;
107 
108 set_prev:
109 	memcpy(&cr->overlap_rec, irec, sizeof(struct xfs_rmap_irec));
110 }
111 
112 /* Decide if two reverse-mapping records can be merged. */
113 static inline bool
114 xchk_rtrmap_mergeable(
115 	struct xchk_rtrmap		*cr,
116 	const struct xfs_rmap_irec	*r2)
117 {
118 	const struct xfs_rmap_irec	*r1 = &cr->prev_rec;
119 
120 	/* Ignore if prev_rec is not yet initialized. */
121 	if (cr->prev_rec.rm_blockcount == 0)
122 		return false;
123 
124 	if (r1->rm_owner != r2->rm_owner)
125 		return false;
126 	if (r1->rm_startblock + r1->rm_blockcount != r2->rm_startblock)
127 		return false;
128 	if ((unsigned long long)r1->rm_blockcount + r2->rm_blockcount >
129 	    XFS_RMAP_LEN_MAX)
130 		return false;
131 	if (r1->rm_flags != r2->rm_flags)
132 		return false;
133 	return r1->rm_offset + r1->rm_blockcount == r2->rm_offset;
134 }
135 
136 /* Flag failures for records that could be merged. */
137 STATIC void
138 xchk_rtrmapbt_check_mergeable(
139 	struct xchk_btree		*bs,
140 	struct xchk_rtrmap		*cr,
141 	const struct xfs_rmap_irec	*irec)
142 {
143 	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
144 		return;
145 
146 	if (xchk_rtrmap_mergeable(cr, irec))
147 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
148 
149 	memcpy(&cr->prev_rec, irec, sizeof(struct xfs_rmap_irec));
150 }
151 
152 /* Cross-reference with other metadata. */
153 STATIC void
154 xchk_rtrmapbt_xref(
155 	struct xfs_scrub	*sc,
156 	struct xfs_rmap_irec	*irec)
157 {
158 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
159 		return;
160 
161 	xchk_xref_is_used_rt_space(sc,
162 			xfs_rgbno_to_rtb(sc->sr.rtg, irec->rm_startblock),
163 			irec->rm_blockcount);
164 }
165 
166 /* Scrub a realtime rmapbt record. */
167 STATIC int
168 xchk_rtrmapbt_rec(
169 	struct xchk_btree		*bs,
170 	const union xfs_btree_rec	*rec)
171 {
172 	struct xchk_rtrmap		*cr = bs->private;
173 	struct xfs_rmap_irec		irec;
174 
175 	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL ||
176 	    xfs_rtrmap_check_irec(to_rtg(bs->cur->bc_group), &irec) != NULL) {
177 		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
178 		return 0;
179 	}
180 
181 	if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
182 		return 0;
183 
184 	xchk_rtrmapbt_check_mergeable(bs, cr, &irec);
185 	xchk_rtrmapbt_check_overlapping(bs, cr, &irec);
186 	xchk_rtrmapbt_xref(bs->sc, &irec);
187 	return 0;
188 }
189 
190 /* Scrub the realtime rmap btree. */
191 int
192 xchk_rtrmapbt(
193 	struct xfs_scrub	*sc)
194 {
195 	struct xfs_inode	*ip = rtg_rmap(sc->sr.rtg);
196 	struct xfs_owner_info	oinfo;
197 	struct xchk_rtrmap	cr = { };
198 	int			error;
199 
200 	error = xchk_metadata_inode_forks(sc);
201 	if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
202 		return error;
203 
204 	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, XFS_DATA_FORK);
205 	return xchk_btree(sc, sc->sr.rmap_cur, xchk_rtrmapbt_rec, &oinfo, &cr);
206 }
207 
208 /* xref check that the extent has no realtime reverse mapping at all */
209 void
210 xchk_xref_has_no_rt_owner(
211 	struct xfs_scrub	*sc,
212 	xfs_rgblock_t		bno,
213 	xfs_extlen_t		len)
214 {
215 	enum xbtree_recpacking	outcome;
216 	int			error;
217 
218 	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
219 		return;
220 
221 	error = xfs_rmap_has_records(sc->sr.rmap_cur, bno, len, &outcome);
222 	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
223 		return;
224 	if (outcome != XBTREE_RECPACKING_EMPTY)
225 		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
226 }
227 
228 /* xref check that the extent is completely mapped */
229 void
230 xchk_xref_has_rt_owner(
231 	struct xfs_scrub	*sc,
232 	xfs_rgblock_t		bno,
233 	xfs_extlen_t		len)
234 {
235 	enum xbtree_recpacking	outcome;
236 	int			error;
237 
238 	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
239 		return;
240 
241 	error = xfs_rmap_has_records(sc->sr.rmap_cur, bno, len, &outcome);
242 	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
243 		return;
244 	if (outcome != XBTREE_RECPACKING_FULL)
245 		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
246 }
247 
248 /* xref check that the extent is only owned by a given owner */
249 void
250 xchk_xref_is_only_rt_owned_by(
251 	struct xfs_scrub		*sc,
252 	xfs_agblock_t			bno,
253 	xfs_extlen_t			len,
254 	const struct xfs_owner_info	*oinfo)
255 {
256 	struct xfs_rmap_matches		res;
257 	int				error;
258 
259 	if (!sc->sr.rmap_cur || xchk_skip_xref(sc->sm))
260 		return;
261 
262 	error = xfs_rmap_count_owners(sc->sr.rmap_cur, bno, len, oinfo, &res);
263 	if (!xchk_should_check_xref(sc, &error, &sc->sr.rmap_cur))
264 		return;
265 	if (res.matches != 1)
266 		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
267 	if (res.bad_non_owner_matches)
268 		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
269 	if (res.non_owner_matches)
270 		xchk_btree_xref_set_corrupt(sc, sc->sr.rmap_cur, 0);
271 }
272