xref: /openbmc/linux/fs/xfs/scrub/rmap.c (revision 82e6fdd6)
1 /*
2  * Copyright (C) 2017 Oracle.  All Rights Reserved.
3  *
4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it would be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write the Free Software Foundation,
18  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
19  */
20 #include "xfs.h"
21 #include "xfs_fs.h"
22 #include "xfs_shared.h"
23 #include "xfs_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_mount.h"
26 #include "xfs_defer.h"
27 #include "xfs_btree.h"
28 #include "xfs_bit.h"
29 #include "xfs_log_format.h"
30 #include "xfs_trans.h"
31 #include "xfs_sb.h"
32 #include "xfs_alloc.h"
33 #include "xfs_ialloc.h"
34 #include "xfs_rmap.h"
35 #include "xfs_refcount.h"
36 #include "scrub/xfs_scrub.h"
37 #include "scrub/scrub.h"
38 #include "scrub/common.h"
39 #include "scrub/btree.h"
40 #include "scrub/trace.h"
41 
42 /*
43  * Set us up to scrub reverse mapping btrees.
44  */
45 int
46 xfs_scrub_setup_ag_rmapbt(
47 	struct xfs_scrub_context	*sc,
48 	struct xfs_inode		*ip)
49 {
50 	return xfs_scrub_setup_ag_btree(sc, ip, false);
51 }
52 
53 /* Reverse-mapping scrubber. */
54 
55 /* Cross-reference a rmap against the refcount btree. */
56 STATIC void
57 xfs_scrub_rmapbt_xref_refc(
58 	struct xfs_scrub_context	*sc,
59 	struct xfs_rmap_irec		*irec)
60 {
61 	xfs_agblock_t			fbno;
62 	xfs_extlen_t			flen;
63 	bool				non_inode;
64 	bool				is_bmbt;
65 	bool				is_attr;
66 	bool				is_unwritten;
67 	int				error;
68 
69 	if (!sc->sa.refc_cur)
70 		return;
71 
72 	non_inode = XFS_RMAP_NON_INODE_OWNER(irec->rm_owner);
73 	is_bmbt = irec->rm_flags & XFS_RMAP_BMBT_BLOCK;
74 	is_attr = irec->rm_flags & XFS_RMAP_ATTR_FORK;
75 	is_unwritten = irec->rm_flags & XFS_RMAP_UNWRITTEN;
76 
77 	/* If this is shared, must be a data fork extent. */
78 	error = xfs_refcount_find_shared(sc->sa.refc_cur, irec->rm_startblock,
79 			irec->rm_blockcount, &fbno, &flen, false);
80 	if (!xfs_scrub_should_check_xref(sc, &error, &sc->sa.refc_cur))
81 		return;
82 	if (flen != 0 && (non_inode || is_attr || is_bmbt || is_unwritten))
83 		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
84 }
85 
86 /* Cross-reference with the other btrees. */
87 STATIC void
88 xfs_scrub_rmapbt_xref(
89 	struct xfs_scrub_context	*sc,
90 	struct xfs_rmap_irec		*irec)
91 {
92 	xfs_agblock_t			agbno = irec->rm_startblock;
93 	xfs_extlen_t			len = irec->rm_blockcount;
94 
95 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
96 		return;
97 
98 	xfs_scrub_xref_is_used_space(sc, agbno, len);
99 	if (irec->rm_owner == XFS_RMAP_OWN_INODES)
100 		xfs_scrub_xref_is_inode_chunk(sc, agbno, len);
101 	else
102 		xfs_scrub_xref_is_not_inode_chunk(sc, agbno, len);
103 	if (irec->rm_owner == XFS_RMAP_OWN_COW)
104 		xfs_scrub_xref_is_cow_staging(sc, irec->rm_startblock,
105 				irec->rm_blockcount);
106 	else
107 		xfs_scrub_rmapbt_xref_refc(sc, irec);
108 }
109 
110 /* Scrub an rmapbt record. */
111 STATIC int
112 xfs_scrub_rmapbt_rec(
113 	struct xfs_scrub_btree		*bs,
114 	union xfs_btree_rec		*rec)
115 {
116 	struct xfs_mount		*mp = bs->cur->bc_mp;
117 	struct xfs_rmap_irec		irec;
118 	xfs_agnumber_t			agno = bs->cur->bc_private.a.agno;
119 	bool				non_inode;
120 	bool				is_unwritten;
121 	bool				is_bmbt;
122 	bool				is_attr;
123 	int				error;
124 
125 	error = xfs_rmap_btrec_to_irec(rec, &irec);
126 	if (!xfs_scrub_btree_process_error(bs->sc, bs->cur, 0, &error))
127 		goto out;
128 
129 	/* Check extent. */
130 	if (irec.rm_startblock + irec.rm_blockcount <= irec.rm_startblock)
131 		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
132 
133 	if (irec.rm_owner == XFS_RMAP_OWN_FS) {
134 		/*
135 		 * xfs_verify_agbno returns false for static fs metadata.
136 		 * Since that only exists at the start of the AG, validate
137 		 * that by hand.
138 		 */
139 		if (irec.rm_startblock != 0 ||
140 		    irec.rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)
141 			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
142 	} else {
143 		/*
144 		 * Otherwise we must point somewhere past the static metadata
145 		 * but before the end of the FS.  Run the regular check.
146 		 */
147 		if (!xfs_verify_agbno(mp, agno, irec.rm_startblock) ||
148 		    !xfs_verify_agbno(mp, agno, irec.rm_startblock +
149 				irec.rm_blockcount - 1))
150 			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
151 	}
152 
153 	/* Check flags. */
154 	non_inode = XFS_RMAP_NON_INODE_OWNER(irec.rm_owner);
155 	is_bmbt = irec.rm_flags & XFS_RMAP_BMBT_BLOCK;
156 	is_attr = irec.rm_flags & XFS_RMAP_ATTR_FORK;
157 	is_unwritten = irec.rm_flags & XFS_RMAP_UNWRITTEN;
158 
159 	if (is_bmbt && irec.rm_offset != 0)
160 		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
161 
162 	if (non_inode && irec.rm_offset != 0)
163 		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
164 
165 	if (is_unwritten && (is_bmbt || non_inode || is_attr))
166 		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
167 
168 	if (non_inode && (is_bmbt || is_unwritten || is_attr))
169 		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
170 
171 	if (!non_inode) {
172 		if (!xfs_verify_ino(mp, irec.rm_owner))
173 			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
174 	} else {
175 		/* Non-inode owner within the magic values? */
176 		if (irec.rm_owner <= XFS_RMAP_OWN_MIN ||
177 		    irec.rm_owner > XFS_RMAP_OWN_FS)
178 			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);
179 	}
180 
181 	xfs_scrub_rmapbt_xref(bs->sc, &irec);
182 out:
183 	return error;
184 }
185 
186 /* Scrub the rmap btree for some AG. */
187 int
188 xfs_scrub_rmapbt(
189 	struct xfs_scrub_context	*sc)
190 {
191 	struct xfs_owner_info		oinfo;
192 
193 	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG);
194 	return xfs_scrub_btree(sc, sc->sa.rmap_cur, xfs_scrub_rmapbt_rec,
195 			&oinfo, NULL);
196 }
197 
198 /* xref check that the extent is owned by a given owner */
199 static inline void
200 xfs_scrub_xref_check_owner(
201 	struct xfs_scrub_context	*sc,
202 	xfs_agblock_t			bno,
203 	xfs_extlen_t			len,
204 	struct xfs_owner_info		*oinfo,
205 	bool				should_have_rmap)
206 {
207 	bool				has_rmap;
208 	int				error;
209 
210 	if (!sc->sa.rmap_cur)
211 		return;
212 
213 	error = xfs_rmap_record_exists(sc->sa.rmap_cur, bno, len, oinfo,
214 			&has_rmap);
215 	if (!xfs_scrub_should_check_xref(sc, &error, &sc->sa.rmap_cur))
216 		return;
217 	if (has_rmap != should_have_rmap)
218 		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
219 }
220 
221 /* xref check that the extent is owned by a given owner */
222 void
223 xfs_scrub_xref_is_owned_by(
224 	struct xfs_scrub_context	*sc,
225 	xfs_agblock_t			bno,
226 	xfs_extlen_t			len,
227 	struct xfs_owner_info		*oinfo)
228 {
229 	xfs_scrub_xref_check_owner(sc, bno, len, oinfo, true);
230 }
231 
232 /* xref check that the extent is not owned by a given owner */
233 void
234 xfs_scrub_xref_is_not_owned_by(
235 	struct xfs_scrub_context	*sc,
236 	xfs_agblock_t			bno,
237 	xfs_extlen_t			len,
238 	struct xfs_owner_info		*oinfo)
239 {
240 	xfs_scrub_xref_check_owner(sc, bno, len, oinfo, false);
241 }
242 
243 /* xref check that the extent has no reverse mapping at all */
244 void
245 xfs_scrub_xref_has_no_owner(
246 	struct xfs_scrub_context	*sc,
247 	xfs_agblock_t			bno,
248 	xfs_extlen_t			len)
249 {
250 	bool				has_rmap;
251 	int				error;
252 
253 	if (!sc->sa.rmap_cur)
254 		return;
255 
256 	error = xfs_rmap_has_record(sc->sa.rmap_cur, bno, len, &has_rmap);
257 	if (!xfs_scrub_should_check_xref(sc, &error, &sc->sa.rmap_cur))
258 		return;
259 	if (has_rmap)
260 		xfs_scrub_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
261 }
262