xref: /openbmc/linux/fs/xfs/scrub/agheader.c (revision d9679d00)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 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_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_btree.h"
13 #include "xfs_sb.h"
14 #include "xfs_alloc.h"
15 #include "xfs_ialloc.h"
16 #include "xfs_rmap.h"
17 #include "xfs_ag.h"
18 #include "scrub/scrub.h"
19 #include "scrub/common.h"
20 
21 /* Superblock */
22 
23 /* Cross-reference with the other btrees. */
24 STATIC void
25 xchk_superblock_xref(
26 	struct xfs_scrub	*sc,
27 	struct xfs_buf		*bp)
28 {
29 	struct xfs_mount	*mp = sc->mp;
30 	xfs_agnumber_t		agno = sc->sm->sm_agno;
31 	xfs_agblock_t		agbno;
32 	int			error;
33 
34 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
35 		return;
36 
37 	agbno = XFS_SB_BLOCK(mp);
38 
39 	error = xchk_ag_init_existing(sc, agno, &sc->sa);
40 	if (!xchk_xref_process_error(sc, agno, agbno, &error))
41 		return;
42 
43 	xchk_xref_is_used_space(sc, agbno, 1);
44 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
45 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
46 	xchk_xref_is_not_shared(sc, agbno, 1);
47 
48 	/* scrub teardown will take care of sc->sa for us */
49 }
50 
51 /*
52  * Scrub the filesystem superblock.
53  *
54  * Note: We do /not/ attempt to check AG 0's superblock.  Mount is
55  * responsible for validating all the geometry information in sb 0, so
56  * if the filesystem is capable of initiating online scrub, then clearly
57  * sb 0 is ok and we can use its information to check everything else.
58  */
59 int
60 xchk_superblock(
61 	struct xfs_scrub	*sc)
62 {
63 	struct xfs_mount	*mp = sc->mp;
64 	struct xfs_buf		*bp;
65 	struct xfs_dsb		*sb;
66 	struct xfs_perag	*pag;
67 	xfs_agnumber_t		agno;
68 	uint32_t		v2_ok;
69 	__be32			features_mask;
70 	int			error;
71 	__be16			vernum_mask;
72 
73 	agno = sc->sm->sm_agno;
74 	if (agno == 0)
75 		return 0;
76 
77 	/*
78 	 * Grab an active reference to the perag structure.  If we can't get
79 	 * it, we're racing with something that's tearing down the AG, so
80 	 * signal that the AG no longer exists.
81 	 */
82 	pag = xfs_perag_get(mp, agno);
83 	if (!pag)
84 		return -ENOENT;
85 
86 	error = xfs_sb_read_secondary(mp, sc->tp, agno, &bp);
87 	/*
88 	 * The superblock verifier can return several different error codes
89 	 * if it thinks the superblock doesn't look right.  For a mount these
90 	 * would all get bounced back to userspace, but if we're here then the
91 	 * fs mounted successfully, which means that this secondary superblock
92 	 * is simply incorrect.  Treat all these codes the same way we treat
93 	 * any corruption.
94 	 */
95 	switch (error) {
96 	case -EINVAL:	/* also -EWRONGFS */
97 	case -ENOSYS:
98 	case -EFBIG:
99 		error = -EFSCORRUPTED;
100 		fallthrough;
101 	default:
102 		break;
103 	}
104 	if (!xchk_process_error(sc, agno, XFS_SB_BLOCK(mp), &error))
105 		goto out_pag;
106 
107 	sb = bp->b_addr;
108 
109 	/*
110 	 * Verify the geometries match.  Fields that are permanently
111 	 * set by mkfs are checked; fields that can be updated later
112 	 * (and are not propagated to backup superblocks) are preen
113 	 * checked.
114 	 */
115 	if (sb->sb_blocksize != cpu_to_be32(mp->m_sb.sb_blocksize))
116 		xchk_block_set_corrupt(sc, bp);
117 
118 	if (sb->sb_dblocks != cpu_to_be64(mp->m_sb.sb_dblocks))
119 		xchk_block_set_corrupt(sc, bp);
120 
121 	if (sb->sb_rblocks != cpu_to_be64(mp->m_sb.sb_rblocks))
122 		xchk_block_set_corrupt(sc, bp);
123 
124 	if (sb->sb_rextents != cpu_to_be64(mp->m_sb.sb_rextents))
125 		xchk_block_set_corrupt(sc, bp);
126 
127 	if (!uuid_equal(&sb->sb_uuid, &mp->m_sb.sb_uuid))
128 		xchk_block_set_preen(sc, bp);
129 
130 	if (sb->sb_logstart != cpu_to_be64(mp->m_sb.sb_logstart))
131 		xchk_block_set_corrupt(sc, bp);
132 
133 	if (sb->sb_rootino != cpu_to_be64(mp->m_sb.sb_rootino))
134 		xchk_block_set_preen(sc, bp);
135 
136 	if (sb->sb_rbmino != cpu_to_be64(mp->m_sb.sb_rbmino))
137 		xchk_block_set_preen(sc, bp);
138 
139 	if (sb->sb_rsumino != cpu_to_be64(mp->m_sb.sb_rsumino))
140 		xchk_block_set_preen(sc, bp);
141 
142 	if (sb->sb_rextsize != cpu_to_be32(mp->m_sb.sb_rextsize))
143 		xchk_block_set_corrupt(sc, bp);
144 
145 	if (sb->sb_agblocks != cpu_to_be32(mp->m_sb.sb_agblocks))
146 		xchk_block_set_corrupt(sc, bp);
147 
148 	if (sb->sb_agcount != cpu_to_be32(mp->m_sb.sb_agcount))
149 		xchk_block_set_corrupt(sc, bp);
150 
151 	if (sb->sb_rbmblocks != cpu_to_be32(mp->m_sb.sb_rbmblocks))
152 		xchk_block_set_corrupt(sc, bp);
153 
154 	if (sb->sb_logblocks != cpu_to_be32(mp->m_sb.sb_logblocks))
155 		xchk_block_set_corrupt(sc, bp);
156 
157 	/* Check sb_versionnum bits that are set at mkfs time. */
158 	vernum_mask = cpu_to_be16(~XFS_SB_VERSION_OKBITS |
159 				  XFS_SB_VERSION_NUMBITS |
160 				  XFS_SB_VERSION_ALIGNBIT |
161 				  XFS_SB_VERSION_DALIGNBIT |
162 				  XFS_SB_VERSION_SHAREDBIT |
163 				  XFS_SB_VERSION_LOGV2BIT |
164 				  XFS_SB_VERSION_SECTORBIT |
165 				  XFS_SB_VERSION_EXTFLGBIT |
166 				  XFS_SB_VERSION_DIRV2BIT);
167 	if ((sb->sb_versionnum & vernum_mask) !=
168 	    (cpu_to_be16(mp->m_sb.sb_versionnum) & vernum_mask))
169 		xchk_block_set_corrupt(sc, bp);
170 
171 	/* Check sb_versionnum bits that can be set after mkfs time. */
172 	vernum_mask = cpu_to_be16(XFS_SB_VERSION_ATTRBIT |
173 				  XFS_SB_VERSION_NLINKBIT |
174 				  XFS_SB_VERSION_QUOTABIT);
175 	if ((sb->sb_versionnum & vernum_mask) !=
176 	    (cpu_to_be16(mp->m_sb.sb_versionnum) & vernum_mask))
177 		xchk_block_set_preen(sc, bp);
178 
179 	if (sb->sb_sectsize != cpu_to_be16(mp->m_sb.sb_sectsize))
180 		xchk_block_set_corrupt(sc, bp);
181 
182 	if (sb->sb_inodesize != cpu_to_be16(mp->m_sb.sb_inodesize))
183 		xchk_block_set_corrupt(sc, bp);
184 
185 	if (sb->sb_inopblock != cpu_to_be16(mp->m_sb.sb_inopblock))
186 		xchk_block_set_corrupt(sc, bp);
187 
188 	if (memcmp(sb->sb_fname, mp->m_sb.sb_fname, sizeof(sb->sb_fname)))
189 		xchk_block_set_preen(sc, bp);
190 
191 	if (sb->sb_blocklog != mp->m_sb.sb_blocklog)
192 		xchk_block_set_corrupt(sc, bp);
193 
194 	if (sb->sb_sectlog != mp->m_sb.sb_sectlog)
195 		xchk_block_set_corrupt(sc, bp);
196 
197 	if (sb->sb_inodelog != mp->m_sb.sb_inodelog)
198 		xchk_block_set_corrupt(sc, bp);
199 
200 	if (sb->sb_inopblog != mp->m_sb.sb_inopblog)
201 		xchk_block_set_corrupt(sc, bp);
202 
203 	if (sb->sb_agblklog != mp->m_sb.sb_agblklog)
204 		xchk_block_set_corrupt(sc, bp);
205 
206 	if (sb->sb_rextslog != mp->m_sb.sb_rextslog)
207 		xchk_block_set_corrupt(sc, bp);
208 
209 	if (sb->sb_imax_pct != mp->m_sb.sb_imax_pct)
210 		xchk_block_set_preen(sc, bp);
211 
212 	/*
213 	 * Skip the summary counters since we track them in memory anyway.
214 	 * sb_icount, sb_ifree, sb_fdblocks, sb_frexents
215 	 */
216 
217 	if (sb->sb_uquotino != cpu_to_be64(mp->m_sb.sb_uquotino))
218 		xchk_block_set_preen(sc, bp);
219 
220 	if (sb->sb_gquotino != cpu_to_be64(mp->m_sb.sb_gquotino))
221 		xchk_block_set_preen(sc, bp);
222 
223 	/*
224 	 * Skip the quota flags since repair will force quotacheck.
225 	 * sb_qflags
226 	 */
227 
228 	if (sb->sb_flags != mp->m_sb.sb_flags)
229 		xchk_block_set_corrupt(sc, bp);
230 
231 	if (sb->sb_shared_vn != mp->m_sb.sb_shared_vn)
232 		xchk_block_set_corrupt(sc, bp);
233 
234 	if (sb->sb_inoalignmt != cpu_to_be32(mp->m_sb.sb_inoalignmt))
235 		xchk_block_set_corrupt(sc, bp);
236 
237 	if (sb->sb_unit != cpu_to_be32(mp->m_sb.sb_unit))
238 		xchk_block_set_preen(sc, bp);
239 
240 	if (sb->sb_width != cpu_to_be32(mp->m_sb.sb_width))
241 		xchk_block_set_preen(sc, bp);
242 
243 	if (sb->sb_dirblklog != mp->m_sb.sb_dirblklog)
244 		xchk_block_set_corrupt(sc, bp);
245 
246 	if (sb->sb_logsectlog != mp->m_sb.sb_logsectlog)
247 		xchk_block_set_corrupt(sc, bp);
248 
249 	if (sb->sb_logsectsize != cpu_to_be16(mp->m_sb.sb_logsectsize))
250 		xchk_block_set_corrupt(sc, bp);
251 
252 	if (sb->sb_logsunit != cpu_to_be32(mp->m_sb.sb_logsunit))
253 		xchk_block_set_corrupt(sc, bp);
254 
255 	/* Do we see any invalid bits in sb_features2? */
256 	if (!xfs_sb_version_hasmorebits(&mp->m_sb)) {
257 		if (sb->sb_features2 != 0)
258 			xchk_block_set_corrupt(sc, bp);
259 	} else {
260 		v2_ok = XFS_SB_VERSION2_OKBITS;
261 		if (xfs_sb_is_v5(&mp->m_sb))
262 			v2_ok |= XFS_SB_VERSION2_CRCBIT;
263 
264 		if (!!(sb->sb_features2 & cpu_to_be32(~v2_ok)))
265 			xchk_block_set_corrupt(sc, bp);
266 
267 		if (sb->sb_features2 != sb->sb_bad_features2)
268 			xchk_block_set_preen(sc, bp);
269 	}
270 
271 	/* Check sb_features2 flags that are set at mkfs time. */
272 	features_mask = cpu_to_be32(XFS_SB_VERSION2_LAZYSBCOUNTBIT |
273 				    XFS_SB_VERSION2_PROJID32BIT |
274 				    XFS_SB_VERSION2_CRCBIT |
275 				    XFS_SB_VERSION2_FTYPE);
276 	if ((sb->sb_features2 & features_mask) !=
277 	    (cpu_to_be32(mp->m_sb.sb_features2) & features_mask))
278 		xchk_block_set_corrupt(sc, bp);
279 
280 	/* Check sb_features2 flags that can be set after mkfs time. */
281 	features_mask = cpu_to_be32(XFS_SB_VERSION2_ATTR2BIT);
282 	if ((sb->sb_features2 & features_mask) !=
283 	    (cpu_to_be32(mp->m_sb.sb_features2) & features_mask))
284 		xchk_block_set_corrupt(sc, bp);
285 
286 	if (!xfs_has_crc(mp)) {
287 		/* all v5 fields must be zero */
288 		if (memchr_inv(&sb->sb_features_compat, 0,
289 				sizeof(struct xfs_dsb) -
290 				offsetof(struct xfs_dsb, sb_features_compat)))
291 			xchk_block_set_corrupt(sc, bp);
292 	} else {
293 		/* Check compat flags; all are set at mkfs time. */
294 		features_mask = cpu_to_be32(XFS_SB_FEAT_COMPAT_UNKNOWN);
295 		if ((sb->sb_features_compat & features_mask) !=
296 		    (cpu_to_be32(mp->m_sb.sb_features_compat) & features_mask))
297 			xchk_block_set_corrupt(sc, bp);
298 
299 		/* Check ro compat flags; all are set at mkfs time. */
300 		features_mask = cpu_to_be32(XFS_SB_FEAT_RO_COMPAT_UNKNOWN |
301 					    XFS_SB_FEAT_RO_COMPAT_FINOBT |
302 					    XFS_SB_FEAT_RO_COMPAT_RMAPBT |
303 					    XFS_SB_FEAT_RO_COMPAT_REFLINK);
304 		if ((sb->sb_features_ro_compat & features_mask) !=
305 		    (cpu_to_be32(mp->m_sb.sb_features_ro_compat) &
306 		     features_mask))
307 			xchk_block_set_corrupt(sc, bp);
308 
309 		/* Check incompat flags; all are set at mkfs time. */
310 		features_mask = cpu_to_be32(XFS_SB_FEAT_INCOMPAT_UNKNOWN |
311 					    XFS_SB_FEAT_INCOMPAT_FTYPE |
312 					    XFS_SB_FEAT_INCOMPAT_SPINODES |
313 					    XFS_SB_FEAT_INCOMPAT_META_UUID);
314 		if ((sb->sb_features_incompat & features_mask) !=
315 		    (cpu_to_be32(mp->m_sb.sb_features_incompat) &
316 		     features_mask))
317 			xchk_block_set_corrupt(sc, bp);
318 
319 		/* Check log incompat flags; all are set at mkfs time. */
320 		features_mask = cpu_to_be32(XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN);
321 		if ((sb->sb_features_log_incompat & features_mask) !=
322 		    (cpu_to_be32(mp->m_sb.sb_features_log_incompat) &
323 		     features_mask))
324 			xchk_block_set_corrupt(sc, bp);
325 
326 		/* Don't care about sb_crc */
327 
328 		if (sb->sb_spino_align != cpu_to_be32(mp->m_sb.sb_spino_align))
329 			xchk_block_set_corrupt(sc, bp);
330 
331 		if (sb->sb_pquotino != cpu_to_be64(mp->m_sb.sb_pquotino))
332 			xchk_block_set_preen(sc, bp);
333 
334 		/* Don't care about sb_lsn */
335 	}
336 
337 	if (xfs_has_metauuid(mp)) {
338 		/* The metadata UUID must be the same for all supers */
339 		if (!uuid_equal(&sb->sb_meta_uuid, &mp->m_sb.sb_meta_uuid))
340 			xchk_block_set_corrupt(sc, bp);
341 	}
342 
343 	/* Everything else must be zero. */
344 	if (memchr_inv(sb + 1, 0,
345 			BBTOB(bp->b_length) - sizeof(struct xfs_dsb)))
346 		xchk_block_set_corrupt(sc, bp);
347 
348 	xchk_superblock_xref(sc, bp);
349 out_pag:
350 	xfs_perag_put(pag);
351 	return error;
352 }
353 
354 /* AGF */
355 
356 /* Tally freespace record lengths. */
357 STATIC int
358 xchk_agf_record_bno_lengths(
359 	struct xfs_btree_cur		*cur,
360 	const struct xfs_alloc_rec_incore *rec,
361 	void				*priv)
362 {
363 	xfs_extlen_t			*blocks = priv;
364 
365 	(*blocks) += rec->ar_blockcount;
366 	return 0;
367 }
368 
369 /* Check agf_freeblks */
370 static inline void
371 xchk_agf_xref_freeblks(
372 	struct xfs_scrub	*sc)
373 {
374 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
375 	xfs_extlen_t		blocks = 0;
376 	int			error;
377 
378 	if (!sc->sa.bno_cur)
379 		return;
380 
381 	error = xfs_alloc_query_all(sc->sa.bno_cur,
382 			xchk_agf_record_bno_lengths, &blocks);
383 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
384 		return;
385 	if (blocks != be32_to_cpu(agf->agf_freeblks))
386 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
387 }
388 
389 /* Cross reference the AGF with the cntbt (freespace by length btree) */
390 static inline void
391 xchk_agf_xref_cntbt(
392 	struct xfs_scrub	*sc)
393 {
394 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
395 	xfs_agblock_t		agbno;
396 	xfs_extlen_t		blocks;
397 	int			have;
398 	int			error;
399 
400 	if (!sc->sa.cnt_cur)
401 		return;
402 
403 	/* Any freespace at all? */
404 	error = xfs_alloc_lookup_le(sc->sa.cnt_cur, 0, -1U, &have);
405 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
406 		return;
407 	if (!have) {
408 		if (agf->agf_freeblks != cpu_to_be32(0))
409 			xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
410 		return;
411 	}
412 
413 	/* Check agf_longest */
414 	error = xfs_alloc_get_rec(sc->sa.cnt_cur, &agbno, &blocks, &have);
415 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
416 		return;
417 	if (!have || blocks != be32_to_cpu(agf->agf_longest))
418 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
419 }
420 
421 /* Check the btree block counts in the AGF against the btrees. */
422 STATIC void
423 xchk_agf_xref_btreeblks(
424 	struct xfs_scrub	*sc)
425 {
426 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
427 	struct xfs_mount	*mp = sc->mp;
428 	xfs_agblock_t		blocks;
429 	xfs_agblock_t		btreeblks;
430 	int			error;
431 
432 	/* agf_btreeblks didn't exist before lazysbcount */
433 	if (!xfs_has_lazysbcount(sc->mp))
434 		return;
435 
436 	/* Check agf_rmap_blocks; set up for agf_btreeblks check */
437 	if (sc->sa.rmap_cur) {
438 		error = xfs_btree_count_blocks(sc->sa.rmap_cur, &blocks);
439 		if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
440 			return;
441 		btreeblks = blocks - 1;
442 		if (blocks != be32_to_cpu(agf->agf_rmap_blocks))
443 			xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
444 	} else {
445 		btreeblks = 0;
446 	}
447 
448 	/*
449 	 * No rmap cursor; we can't xref if we have the rmapbt feature.
450 	 * We also can't do it if we're missing the free space btree cursors.
451 	 */
452 	if ((xfs_has_rmapbt(mp) && !sc->sa.rmap_cur) ||
453 	    !sc->sa.bno_cur || !sc->sa.cnt_cur)
454 		return;
455 
456 	/* Check agf_btreeblks */
457 	error = xfs_btree_count_blocks(sc->sa.bno_cur, &blocks);
458 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
459 		return;
460 	btreeblks += blocks - 1;
461 
462 	error = xfs_btree_count_blocks(sc->sa.cnt_cur, &blocks);
463 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
464 		return;
465 	btreeblks += blocks - 1;
466 
467 	if (btreeblks != be32_to_cpu(agf->agf_btreeblks))
468 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
469 }
470 
471 /* Check agf_refcount_blocks against tree size */
472 static inline void
473 xchk_agf_xref_refcblks(
474 	struct xfs_scrub	*sc)
475 {
476 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
477 	xfs_agblock_t		blocks;
478 	int			error;
479 
480 	if (!sc->sa.refc_cur)
481 		return;
482 
483 	error = xfs_btree_count_blocks(sc->sa.refc_cur, &blocks);
484 	if (!xchk_should_check_xref(sc, &error, &sc->sa.refc_cur))
485 		return;
486 	if (blocks != be32_to_cpu(agf->agf_refcount_blocks))
487 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
488 }
489 
490 /* Cross-reference with the other btrees. */
491 STATIC void
492 xchk_agf_xref(
493 	struct xfs_scrub	*sc)
494 {
495 	struct xfs_mount	*mp = sc->mp;
496 	xfs_agblock_t		agbno;
497 
498 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
499 		return;
500 
501 	agbno = XFS_AGF_BLOCK(mp);
502 
503 	xchk_ag_btcur_init(sc, &sc->sa);
504 
505 	xchk_xref_is_used_space(sc, agbno, 1);
506 	xchk_agf_xref_freeblks(sc);
507 	xchk_agf_xref_cntbt(sc);
508 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
509 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
510 	xchk_agf_xref_btreeblks(sc);
511 	xchk_xref_is_not_shared(sc, agbno, 1);
512 	xchk_agf_xref_refcblks(sc);
513 
514 	/* scrub teardown will take care of sc->sa for us */
515 }
516 
517 /* Scrub the AGF. */
518 int
519 xchk_agf(
520 	struct xfs_scrub	*sc)
521 {
522 	struct xfs_mount	*mp = sc->mp;
523 	struct xfs_agf		*agf;
524 	struct xfs_perag	*pag;
525 	xfs_agnumber_t		agno = sc->sm->sm_agno;
526 	xfs_agblock_t		agbno;
527 	xfs_agblock_t		eoag;
528 	xfs_agblock_t		agfl_first;
529 	xfs_agblock_t		agfl_last;
530 	xfs_agblock_t		agfl_count;
531 	xfs_agblock_t		fl_count;
532 	int			level;
533 	int			error = 0;
534 
535 	error = xchk_ag_read_headers(sc, agno, &sc->sa);
536 	if (!xchk_process_error(sc, agno, XFS_AGF_BLOCK(sc->mp), &error))
537 		goto out;
538 	xchk_buffer_recheck(sc, sc->sa.agf_bp);
539 
540 	agf = sc->sa.agf_bp->b_addr;
541 	pag = sc->sa.pag;
542 
543 	/* Check the AG length */
544 	eoag = be32_to_cpu(agf->agf_length);
545 	if (eoag != xfs_ag_block_count(mp, agno))
546 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
547 
548 	/* Check the AGF btree roots and levels */
549 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_BNO]);
550 	if (!xfs_verify_agbno(mp, agno, agbno))
551 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
552 
553 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_CNT]);
554 	if (!xfs_verify_agbno(mp, agno, agbno))
555 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
556 
557 	level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
558 	if (level <= 0 || level > mp->m_alloc_maxlevels)
559 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
560 
561 	level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
562 	if (level <= 0 || level > mp->m_alloc_maxlevels)
563 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
564 
565 	if (xfs_has_rmapbt(mp)) {
566 		agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_RMAP]);
567 		if (!xfs_verify_agbno(mp, agno, agbno))
568 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
569 
570 		level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
571 		if (level <= 0 || level > mp->m_rmap_maxlevels)
572 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
573 	}
574 
575 	if (xfs_has_reflink(mp)) {
576 		agbno = be32_to_cpu(agf->agf_refcount_root);
577 		if (!xfs_verify_agbno(mp, agno, agbno))
578 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
579 
580 		level = be32_to_cpu(agf->agf_refcount_level);
581 		if (level <= 0 || level > mp->m_refc_maxlevels)
582 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
583 	}
584 
585 	/* Check the AGFL counters */
586 	agfl_first = be32_to_cpu(agf->agf_flfirst);
587 	agfl_last = be32_to_cpu(agf->agf_fllast);
588 	agfl_count = be32_to_cpu(agf->agf_flcount);
589 	if (agfl_last > agfl_first)
590 		fl_count = agfl_last - agfl_first + 1;
591 	else
592 		fl_count = xfs_agfl_size(mp) - agfl_first + agfl_last + 1;
593 	if (agfl_count != 0 && fl_count != agfl_count)
594 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
595 
596 	/* Do the incore counters match? */
597 	if (pag->pagf_freeblks != be32_to_cpu(agf->agf_freeblks))
598 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
599 	if (pag->pagf_flcount != be32_to_cpu(agf->agf_flcount))
600 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
601 	if (xfs_has_lazysbcount(sc->mp) &&
602 	    pag->pagf_btreeblks != be32_to_cpu(agf->agf_btreeblks))
603 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
604 
605 	xchk_agf_xref(sc);
606 out:
607 	return error;
608 }
609 
610 /* AGFL */
611 
612 struct xchk_agfl_info {
613 	unsigned int		sz_entries;
614 	unsigned int		nr_entries;
615 	xfs_agblock_t		*entries;
616 	struct xfs_scrub	*sc;
617 };
618 
619 /* Cross-reference with the other btrees. */
620 STATIC void
621 xchk_agfl_block_xref(
622 	struct xfs_scrub	*sc,
623 	xfs_agblock_t		agbno)
624 {
625 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
626 		return;
627 
628 	xchk_xref_is_used_space(sc, agbno, 1);
629 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
630 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_AG);
631 	xchk_xref_is_not_shared(sc, agbno, 1);
632 }
633 
634 /* Scrub an AGFL block. */
635 STATIC int
636 xchk_agfl_block(
637 	struct xfs_mount	*mp,
638 	xfs_agblock_t		agbno,
639 	void			*priv)
640 {
641 	struct xchk_agfl_info	*sai = priv;
642 	struct xfs_scrub	*sc = sai->sc;
643 	xfs_agnumber_t		agno = sc->sa.pag->pag_agno;
644 
645 	if (xfs_verify_agbno(mp, agno, agbno) &&
646 	    sai->nr_entries < sai->sz_entries)
647 		sai->entries[sai->nr_entries++] = agbno;
648 	else
649 		xchk_block_set_corrupt(sc, sc->sa.agfl_bp);
650 
651 	xchk_agfl_block_xref(sc, agbno);
652 
653 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
654 		return -ECANCELED;
655 
656 	return 0;
657 }
658 
659 static int
660 xchk_agblock_cmp(
661 	const void		*pa,
662 	const void		*pb)
663 {
664 	const xfs_agblock_t	*a = pa;
665 	const xfs_agblock_t	*b = pb;
666 
667 	return (int)*a - (int)*b;
668 }
669 
670 /* Cross-reference with the other btrees. */
671 STATIC void
672 xchk_agfl_xref(
673 	struct xfs_scrub	*sc)
674 {
675 	struct xfs_mount	*mp = sc->mp;
676 	xfs_agblock_t		agbno;
677 
678 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
679 		return;
680 
681 	agbno = XFS_AGFL_BLOCK(mp);
682 
683 	xchk_ag_btcur_init(sc, &sc->sa);
684 
685 	xchk_xref_is_used_space(sc, agbno, 1);
686 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
687 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
688 	xchk_xref_is_not_shared(sc, agbno, 1);
689 
690 	/*
691 	 * Scrub teardown will take care of sc->sa for us.  Leave sc->sa
692 	 * active so that the agfl block xref can use it too.
693 	 */
694 }
695 
696 /* Scrub the AGFL. */
697 int
698 xchk_agfl(
699 	struct xfs_scrub	*sc)
700 {
701 	struct xchk_agfl_info	sai;
702 	struct xfs_agf		*agf;
703 	xfs_agnumber_t		agno = sc->sm->sm_agno;
704 	unsigned int		agflcount;
705 	unsigned int		i;
706 	int			error;
707 
708 	error = xchk_ag_read_headers(sc, agno, &sc->sa);
709 	if (!xchk_process_error(sc, agno, XFS_AGFL_BLOCK(sc->mp), &error))
710 		goto out;
711 	if (!sc->sa.agf_bp)
712 		return -EFSCORRUPTED;
713 	xchk_buffer_recheck(sc, sc->sa.agfl_bp);
714 
715 	xchk_agfl_xref(sc);
716 
717 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
718 		goto out;
719 
720 	/* Allocate buffer to ensure uniqueness of AGFL entries. */
721 	agf = sc->sa.agf_bp->b_addr;
722 	agflcount = be32_to_cpu(agf->agf_flcount);
723 	if (agflcount > xfs_agfl_size(sc->mp)) {
724 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
725 		goto out;
726 	}
727 	memset(&sai, 0, sizeof(sai));
728 	sai.sc = sc;
729 	sai.sz_entries = agflcount;
730 	sai.entries = kmem_zalloc(sizeof(xfs_agblock_t) * agflcount,
731 			KM_MAYFAIL);
732 	if (!sai.entries) {
733 		error = -ENOMEM;
734 		goto out;
735 	}
736 
737 	/* Check the blocks in the AGFL. */
738 	error = xfs_agfl_walk(sc->mp, sc->sa.agf_bp->b_addr,
739 			sc->sa.agfl_bp, xchk_agfl_block, &sai);
740 	if (error == -ECANCELED) {
741 		error = 0;
742 		goto out_free;
743 	}
744 	if (error)
745 		goto out_free;
746 
747 	if (agflcount != sai.nr_entries) {
748 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
749 		goto out_free;
750 	}
751 
752 	/* Sort entries, check for duplicates. */
753 	sort(sai.entries, sai.nr_entries, sizeof(sai.entries[0]),
754 			xchk_agblock_cmp, NULL);
755 	for (i = 1; i < sai.nr_entries; i++) {
756 		if (sai.entries[i] == sai.entries[i - 1]) {
757 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
758 			break;
759 		}
760 	}
761 
762 out_free:
763 	kmem_free(sai.entries);
764 out:
765 	return error;
766 }
767 
768 /* AGI */
769 
770 /* Check agi_count/agi_freecount */
771 static inline void
772 xchk_agi_xref_icounts(
773 	struct xfs_scrub	*sc)
774 {
775 	struct xfs_agi		*agi = sc->sa.agi_bp->b_addr;
776 	xfs_agino_t		icount;
777 	xfs_agino_t		freecount;
778 	int			error;
779 
780 	if (!sc->sa.ino_cur)
781 		return;
782 
783 	error = xfs_ialloc_count_inodes(sc->sa.ino_cur, &icount, &freecount);
784 	if (!xchk_should_check_xref(sc, &error, &sc->sa.ino_cur))
785 		return;
786 	if (be32_to_cpu(agi->agi_count) != icount ||
787 	    be32_to_cpu(agi->agi_freecount) != freecount)
788 		xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
789 }
790 
791 /* Check agi_[fi]blocks against tree size */
792 static inline void
793 xchk_agi_xref_fiblocks(
794 	struct xfs_scrub	*sc)
795 {
796 	struct xfs_agi		*agi = sc->sa.agi_bp->b_addr;
797 	xfs_agblock_t		blocks;
798 	int			error = 0;
799 
800 	if (!xfs_has_inobtcounts(sc->mp))
801 		return;
802 
803 	if (sc->sa.ino_cur) {
804 		error = xfs_btree_count_blocks(sc->sa.ino_cur, &blocks);
805 		if (!xchk_should_check_xref(sc, &error, &sc->sa.ino_cur))
806 			return;
807 		if (blocks != be32_to_cpu(agi->agi_iblocks))
808 			xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
809 	}
810 
811 	if (sc->sa.fino_cur) {
812 		error = xfs_btree_count_blocks(sc->sa.fino_cur, &blocks);
813 		if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur))
814 			return;
815 		if (blocks != be32_to_cpu(agi->agi_fblocks))
816 			xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
817 	}
818 }
819 
820 /* Cross-reference with the other btrees. */
821 STATIC void
822 xchk_agi_xref(
823 	struct xfs_scrub	*sc)
824 {
825 	struct xfs_mount	*mp = sc->mp;
826 	xfs_agblock_t		agbno;
827 
828 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
829 		return;
830 
831 	agbno = XFS_AGI_BLOCK(mp);
832 
833 	xchk_ag_btcur_init(sc, &sc->sa);
834 
835 	xchk_xref_is_used_space(sc, agbno, 1);
836 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
837 	xchk_agi_xref_icounts(sc);
838 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
839 	xchk_xref_is_not_shared(sc, agbno, 1);
840 	xchk_agi_xref_fiblocks(sc);
841 
842 	/* scrub teardown will take care of sc->sa for us */
843 }
844 
845 /* Scrub the AGI. */
846 int
847 xchk_agi(
848 	struct xfs_scrub	*sc)
849 {
850 	struct xfs_mount	*mp = sc->mp;
851 	struct xfs_agi		*agi;
852 	struct xfs_perag	*pag;
853 	struct xfs_ino_geometry	*igeo = M_IGEO(sc->mp);
854 	xfs_agnumber_t		agno = sc->sm->sm_agno;
855 	xfs_agblock_t		agbno;
856 	xfs_agblock_t		eoag;
857 	xfs_agino_t		agino;
858 	xfs_agino_t		first_agino;
859 	xfs_agino_t		last_agino;
860 	xfs_agino_t		icount;
861 	int			i;
862 	int			level;
863 	int			error = 0;
864 
865 	error = xchk_ag_read_headers(sc, agno, &sc->sa);
866 	if (!xchk_process_error(sc, agno, XFS_AGI_BLOCK(sc->mp), &error))
867 		goto out;
868 	xchk_buffer_recheck(sc, sc->sa.agi_bp);
869 
870 	agi = sc->sa.agi_bp->b_addr;
871 	pag = sc->sa.pag;
872 
873 	/* Check the AG length */
874 	eoag = be32_to_cpu(agi->agi_length);
875 	if (eoag != xfs_ag_block_count(mp, agno))
876 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
877 
878 	/* Check btree roots and levels */
879 	agbno = be32_to_cpu(agi->agi_root);
880 	if (!xfs_verify_agbno(mp, agno, agbno))
881 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
882 
883 	level = be32_to_cpu(agi->agi_level);
884 	if (level <= 0 || level > igeo->inobt_maxlevels)
885 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
886 
887 	if (xfs_has_finobt(mp)) {
888 		agbno = be32_to_cpu(agi->agi_free_root);
889 		if (!xfs_verify_agbno(mp, agno, agbno))
890 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
891 
892 		level = be32_to_cpu(agi->agi_free_level);
893 		if (level <= 0 || level > igeo->inobt_maxlevels)
894 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
895 	}
896 
897 	/* Check inode counters */
898 	xfs_agino_range(mp, agno, &first_agino, &last_agino);
899 	icount = be32_to_cpu(agi->agi_count);
900 	if (icount > last_agino - first_agino + 1 ||
901 	    icount < be32_to_cpu(agi->agi_freecount))
902 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
903 
904 	/* Check inode pointers */
905 	agino = be32_to_cpu(agi->agi_newino);
906 	if (!xfs_verify_agino_or_null(mp, agno, agino))
907 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
908 
909 	agino = be32_to_cpu(agi->agi_dirino);
910 	if (!xfs_verify_agino_or_null(mp, agno, agino))
911 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
912 
913 	/* Check unlinked inode buckets */
914 	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
915 		agino = be32_to_cpu(agi->agi_unlinked[i]);
916 		if (!xfs_verify_agino_or_null(mp, agno, agino))
917 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
918 	}
919 
920 	if (agi->agi_pad32 != cpu_to_be32(0))
921 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
922 
923 	/* Do the incore counters match? */
924 	if (pag->pagi_count != be32_to_cpu(agi->agi_count))
925 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
926 	if (pag->pagi_freecount != be32_to_cpu(agi->agi_freecount))
927 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
928 
929 	xchk_agi_xref(sc);
930 out:
931 	return error;
932 }
933