xref: /linux/fs/xfs/scrub/agheader.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 "scrub/scrub.h"
18 #include "scrub/common.h"
19 
20 /* Superblock */
21 
22 /* Cross-reference with the other btrees. */
23 STATIC void
24 xchk_superblock_xref(
25 	struct xfs_scrub	*sc,
26 	struct xfs_buf		*bp)
27 {
28 	struct xfs_mount	*mp = sc->mp;
29 	xfs_agnumber_t		agno = sc->sm->sm_agno;
30 	xfs_agblock_t		agbno;
31 	int			error;
32 
33 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
34 		return;
35 
36 	agbno = XFS_SB_BLOCK(mp);
37 
38 	error = xchk_ag_init(sc, agno, &sc->sa);
39 	if (!xchk_xref_process_error(sc, agno, agbno, &error))
40 		return;
41 
42 	xchk_xref_is_used_space(sc, agbno, 1);
43 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
44 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
45 	xchk_xref_is_not_shared(sc, agbno, 1);
46 
47 	/* scrub teardown will take care of sc->sa for us */
48 }
49 
50 /*
51  * Scrub the filesystem superblock.
52  *
53  * Note: We do /not/ attempt to check AG 0's superblock.  Mount is
54  * responsible for validating all the geometry information in sb 0, so
55  * if the filesystem is capable of initiating online scrub, then clearly
56  * sb 0 is ok and we can use its information to check everything else.
57  */
58 int
59 xchk_superblock(
60 	struct xfs_scrub	*sc)
61 {
62 	struct xfs_mount	*mp = sc->mp;
63 	struct xfs_buf		*bp;
64 	struct xfs_dsb		*sb;
65 	xfs_agnumber_t		agno;
66 	uint32_t		v2_ok;
67 	__be32			features_mask;
68 	int			error;
69 	__be16			vernum_mask;
70 
71 	agno = sc->sm->sm_agno;
72 	if (agno == 0)
73 		return 0;
74 
75 	error = xfs_sb_read_secondary(mp, sc->tp, agno, &bp);
76 	/*
77 	 * The superblock verifier can return several different error codes
78 	 * if it thinks the superblock doesn't look right.  For a mount these
79 	 * would all get bounced back to userspace, but if we're here then the
80 	 * fs mounted successfully, which means that this secondary superblock
81 	 * is simply incorrect.  Treat all these codes the same way we treat
82 	 * any corruption.
83 	 */
84 	switch (error) {
85 	case -EINVAL:	/* also -EWRONGFS */
86 	case -ENOSYS:
87 	case -EFBIG:
88 		error = -EFSCORRUPTED;
89 	default:
90 		break;
91 	}
92 	if (!xchk_process_error(sc, agno, XFS_SB_BLOCK(mp), &error))
93 		return error;
94 
95 	sb = bp->b_addr;
96 
97 	/*
98 	 * Verify the geometries match.  Fields that are permanently
99 	 * set by mkfs are checked; fields that can be updated later
100 	 * (and are not propagated to backup superblocks) are preen
101 	 * checked.
102 	 */
103 	if (sb->sb_blocksize != cpu_to_be32(mp->m_sb.sb_blocksize))
104 		xchk_block_set_corrupt(sc, bp);
105 
106 	if (sb->sb_dblocks != cpu_to_be64(mp->m_sb.sb_dblocks))
107 		xchk_block_set_corrupt(sc, bp);
108 
109 	if (sb->sb_rblocks != cpu_to_be64(mp->m_sb.sb_rblocks))
110 		xchk_block_set_corrupt(sc, bp);
111 
112 	if (sb->sb_rextents != cpu_to_be64(mp->m_sb.sb_rextents))
113 		xchk_block_set_corrupt(sc, bp);
114 
115 	if (!uuid_equal(&sb->sb_uuid, &mp->m_sb.sb_uuid))
116 		xchk_block_set_preen(sc, bp);
117 
118 	if (sb->sb_logstart != cpu_to_be64(mp->m_sb.sb_logstart))
119 		xchk_block_set_corrupt(sc, bp);
120 
121 	if (sb->sb_rootino != cpu_to_be64(mp->m_sb.sb_rootino))
122 		xchk_block_set_preen(sc, bp);
123 
124 	if (sb->sb_rbmino != cpu_to_be64(mp->m_sb.sb_rbmino))
125 		xchk_block_set_preen(sc, bp);
126 
127 	if (sb->sb_rsumino != cpu_to_be64(mp->m_sb.sb_rsumino))
128 		xchk_block_set_preen(sc, bp);
129 
130 	if (sb->sb_rextsize != cpu_to_be32(mp->m_sb.sb_rextsize))
131 		xchk_block_set_corrupt(sc, bp);
132 
133 	if (sb->sb_agblocks != cpu_to_be32(mp->m_sb.sb_agblocks))
134 		xchk_block_set_corrupt(sc, bp);
135 
136 	if (sb->sb_agcount != cpu_to_be32(mp->m_sb.sb_agcount))
137 		xchk_block_set_corrupt(sc, bp);
138 
139 	if (sb->sb_rbmblocks != cpu_to_be32(mp->m_sb.sb_rbmblocks))
140 		xchk_block_set_corrupt(sc, bp);
141 
142 	if (sb->sb_logblocks != cpu_to_be32(mp->m_sb.sb_logblocks))
143 		xchk_block_set_corrupt(sc, bp);
144 
145 	/* Check sb_versionnum bits that are set at mkfs time. */
146 	vernum_mask = cpu_to_be16(~XFS_SB_VERSION_OKBITS |
147 				  XFS_SB_VERSION_NUMBITS |
148 				  XFS_SB_VERSION_ALIGNBIT |
149 				  XFS_SB_VERSION_DALIGNBIT |
150 				  XFS_SB_VERSION_SHAREDBIT |
151 				  XFS_SB_VERSION_LOGV2BIT |
152 				  XFS_SB_VERSION_SECTORBIT |
153 				  XFS_SB_VERSION_EXTFLGBIT |
154 				  XFS_SB_VERSION_DIRV2BIT);
155 	if ((sb->sb_versionnum & vernum_mask) !=
156 	    (cpu_to_be16(mp->m_sb.sb_versionnum) & vernum_mask))
157 		xchk_block_set_corrupt(sc, bp);
158 
159 	/* Check sb_versionnum bits that can be set after mkfs time. */
160 	vernum_mask = cpu_to_be16(XFS_SB_VERSION_ATTRBIT |
161 				  XFS_SB_VERSION_NLINKBIT |
162 				  XFS_SB_VERSION_QUOTABIT);
163 	if ((sb->sb_versionnum & vernum_mask) !=
164 	    (cpu_to_be16(mp->m_sb.sb_versionnum) & vernum_mask))
165 		xchk_block_set_preen(sc, bp);
166 
167 	if (sb->sb_sectsize != cpu_to_be16(mp->m_sb.sb_sectsize))
168 		xchk_block_set_corrupt(sc, bp);
169 
170 	if (sb->sb_inodesize != cpu_to_be16(mp->m_sb.sb_inodesize))
171 		xchk_block_set_corrupt(sc, bp);
172 
173 	if (sb->sb_inopblock != cpu_to_be16(mp->m_sb.sb_inopblock))
174 		xchk_block_set_corrupt(sc, bp);
175 
176 	if (memcmp(sb->sb_fname, mp->m_sb.sb_fname, sizeof(sb->sb_fname)))
177 		xchk_block_set_preen(sc, bp);
178 
179 	if (sb->sb_blocklog != mp->m_sb.sb_blocklog)
180 		xchk_block_set_corrupt(sc, bp);
181 
182 	if (sb->sb_sectlog != mp->m_sb.sb_sectlog)
183 		xchk_block_set_corrupt(sc, bp);
184 
185 	if (sb->sb_inodelog != mp->m_sb.sb_inodelog)
186 		xchk_block_set_corrupt(sc, bp);
187 
188 	if (sb->sb_inopblog != mp->m_sb.sb_inopblog)
189 		xchk_block_set_corrupt(sc, bp);
190 
191 	if (sb->sb_agblklog != mp->m_sb.sb_agblklog)
192 		xchk_block_set_corrupt(sc, bp);
193 
194 	if (sb->sb_rextslog != mp->m_sb.sb_rextslog)
195 		xchk_block_set_corrupt(sc, bp);
196 
197 	if (sb->sb_imax_pct != mp->m_sb.sb_imax_pct)
198 		xchk_block_set_preen(sc, bp);
199 
200 	/*
201 	 * Skip the summary counters since we track them in memory anyway.
202 	 * sb_icount, sb_ifree, sb_fdblocks, sb_frexents
203 	 */
204 
205 	if (sb->sb_uquotino != cpu_to_be64(mp->m_sb.sb_uquotino))
206 		xchk_block_set_preen(sc, bp);
207 
208 	if (sb->sb_gquotino != cpu_to_be64(mp->m_sb.sb_gquotino))
209 		xchk_block_set_preen(sc, bp);
210 
211 	/*
212 	 * Skip the quota flags since repair will force quotacheck.
213 	 * sb_qflags
214 	 */
215 
216 	if (sb->sb_flags != mp->m_sb.sb_flags)
217 		xchk_block_set_corrupt(sc, bp);
218 
219 	if (sb->sb_shared_vn != mp->m_sb.sb_shared_vn)
220 		xchk_block_set_corrupt(sc, bp);
221 
222 	if (sb->sb_inoalignmt != cpu_to_be32(mp->m_sb.sb_inoalignmt))
223 		xchk_block_set_corrupt(sc, bp);
224 
225 	if (sb->sb_unit != cpu_to_be32(mp->m_sb.sb_unit))
226 		xchk_block_set_preen(sc, bp);
227 
228 	if (sb->sb_width != cpu_to_be32(mp->m_sb.sb_width))
229 		xchk_block_set_preen(sc, bp);
230 
231 	if (sb->sb_dirblklog != mp->m_sb.sb_dirblklog)
232 		xchk_block_set_corrupt(sc, bp);
233 
234 	if (sb->sb_logsectlog != mp->m_sb.sb_logsectlog)
235 		xchk_block_set_corrupt(sc, bp);
236 
237 	if (sb->sb_logsectsize != cpu_to_be16(mp->m_sb.sb_logsectsize))
238 		xchk_block_set_corrupt(sc, bp);
239 
240 	if (sb->sb_logsunit != cpu_to_be32(mp->m_sb.sb_logsunit))
241 		xchk_block_set_corrupt(sc, bp);
242 
243 	/* Do we see any invalid bits in sb_features2? */
244 	if (!xfs_sb_version_hasmorebits(&mp->m_sb)) {
245 		if (sb->sb_features2 != 0)
246 			xchk_block_set_corrupt(sc, bp);
247 	} else {
248 		v2_ok = XFS_SB_VERSION2_OKBITS;
249 		if (XFS_SB_VERSION_NUM(&mp->m_sb) >= XFS_SB_VERSION_5)
250 			v2_ok |= XFS_SB_VERSION2_CRCBIT;
251 
252 		if (!!(sb->sb_features2 & cpu_to_be32(~v2_ok)))
253 			xchk_block_set_corrupt(sc, bp);
254 
255 		if (sb->sb_features2 != sb->sb_bad_features2)
256 			xchk_block_set_preen(sc, bp);
257 	}
258 
259 	/* Check sb_features2 flags that are set at mkfs time. */
260 	features_mask = cpu_to_be32(XFS_SB_VERSION2_LAZYSBCOUNTBIT |
261 				    XFS_SB_VERSION2_PROJID32BIT |
262 				    XFS_SB_VERSION2_CRCBIT |
263 				    XFS_SB_VERSION2_FTYPE);
264 	if ((sb->sb_features2 & features_mask) !=
265 	    (cpu_to_be32(mp->m_sb.sb_features2) & features_mask))
266 		xchk_block_set_corrupt(sc, bp);
267 
268 	/* Check sb_features2 flags that can be set after mkfs time. */
269 	features_mask = cpu_to_be32(XFS_SB_VERSION2_ATTR2BIT);
270 	if ((sb->sb_features2 & features_mask) !=
271 	    (cpu_to_be32(mp->m_sb.sb_features2) & features_mask))
272 		xchk_block_set_corrupt(sc, bp);
273 
274 	if (!xfs_sb_version_hascrc(&mp->m_sb)) {
275 		/* all v5 fields must be zero */
276 		if (memchr_inv(&sb->sb_features_compat, 0,
277 				sizeof(struct xfs_dsb) -
278 				offsetof(struct xfs_dsb, sb_features_compat)))
279 			xchk_block_set_corrupt(sc, bp);
280 	} else {
281 		/* Check compat flags; all are set at mkfs time. */
282 		features_mask = cpu_to_be32(XFS_SB_FEAT_COMPAT_UNKNOWN);
283 		if ((sb->sb_features_compat & features_mask) !=
284 		    (cpu_to_be32(mp->m_sb.sb_features_compat) & features_mask))
285 			xchk_block_set_corrupt(sc, bp);
286 
287 		/* Check ro compat flags; all are set at mkfs time. */
288 		features_mask = cpu_to_be32(XFS_SB_FEAT_RO_COMPAT_UNKNOWN |
289 					    XFS_SB_FEAT_RO_COMPAT_FINOBT |
290 					    XFS_SB_FEAT_RO_COMPAT_RMAPBT |
291 					    XFS_SB_FEAT_RO_COMPAT_REFLINK);
292 		if ((sb->sb_features_ro_compat & features_mask) !=
293 		    (cpu_to_be32(mp->m_sb.sb_features_ro_compat) &
294 		     features_mask))
295 			xchk_block_set_corrupt(sc, bp);
296 
297 		/* Check incompat flags; all are set at mkfs time. */
298 		features_mask = cpu_to_be32(XFS_SB_FEAT_INCOMPAT_UNKNOWN |
299 					    XFS_SB_FEAT_INCOMPAT_FTYPE |
300 					    XFS_SB_FEAT_INCOMPAT_SPINODES |
301 					    XFS_SB_FEAT_INCOMPAT_META_UUID);
302 		if ((sb->sb_features_incompat & features_mask) !=
303 		    (cpu_to_be32(mp->m_sb.sb_features_incompat) &
304 		     features_mask))
305 			xchk_block_set_corrupt(sc, bp);
306 
307 		/* Check log incompat flags; all are set at mkfs time. */
308 		features_mask = cpu_to_be32(XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN);
309 		if ((sb->sb_features_log_incompat & features_mask) !=
310 		    (cpu_to_be32(mp->m_sb.sb_features_log_incompat) &
311 		     features_mask))
312 			xchk_block_set_corrupt(sc, bp);
313 
314 		/* Don't care about sb_crc */
315 
316 		if (sb->sb_spino_align != cpu_to_be32(mp->m_sb.sb_spino_align))
317 			xchk_block_set_corrupt(sc, bp);
318 
319 		if (sb->sb_pquotino != cpu_to_be64(mp->m_sb.sb_pquotino))
320 			xchk_block_set_preen(sc, bp);
321 
322 		/* Don't care about sb_lsn */
323 	}
324 
325 	if (xfs_sb_version_hasmetauuid(&mp->m_sb)) {
326 		/* The metadata UUID must be the same for all supers */
327 		if (!uuid_equal(&sb->sb_meta_uuid, &mp->m_sb.sb_meta_uuid))
328 			xchk_block_set_corrupt(sc, bp);
329 	}
330 
331 	/* Everything else must be zero. */
332 	if (memchr_inv(sb + 1, 0,
333 			BBTOB(bp->b_length) - sizeof(struct xfs_dsb)))
334 		xchk_block_set_corrupt(sc, bp);
335 
336 	xchk_superblock_xref(sc, bp);
337 
338 	return error;
339 }
340 
341 /* AGF */
342 
343 /* Tally freespace record lengths. */
344 STATIC int
345 xchk_agf_record_bno_lengths(
346 	struct xfs_btree_cur		*cur,
347 	struct xfs_alloc_rec_incore	*rec,
348 	void				*priv)
349 {
350 	xfs_extlen_t			*blocks = priv;
351 
352 	(*blocks) += rec->ar_blockcount;
353 	return 0;
354 }
355 
356 /* Check agf_freeblks */
357 static inline void
358 xchk_agf_xref_freeblks(
359 	struct xfs_scrub	*sc)
360 {
361 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
362 	xfs_extlen_t		blocks = 0;
363 	int			error;
364 
365 	if (!sc->sa.bno_cur)
366 		return;
367 
368 	error = xfs_alloc_query_all(sc->sa.bno_cur,
369 			xchk_agf_record_bno_lengths, &blocks);
370 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
371 		return;
372 	if (blocks != be32_to_cpu(agf->agf_freeblks))
373 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
374 }
375 
376 /* Cross reference the AGF with the cntbt (freespace by length btree) */
377 static inline void
378 xchk_agf_xref_cntbt(
379 	struct xfs_scrub	*sc)
380 {
381 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
382 	xfs_agblock_t		agbno;
383 	xfs_extlen_t		blocks;
384 	int			have;
385 	int			error;
386 
387 	if (!sc->sa.cnt_cur)
388 		return;
389 
390 	/* Any freespace at all? */
391 	error = xfs_alloc_lookup_le(sc->sa.cnt_cur, 0, -1U, &have);
392 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
393 		return;
394 	if (!have) {
395 		if (agf->agf_freeblks != cpu_to_be32(0))
396 			xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
397 		return;
398 	}
399 
400 	/* Check agf_longest */
401 	error = xfs_alloc_get_rec(sc->sa.cnt_cur, &agbno, &blocks, &have);
402 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
403 		return;
404 	if (!have || blocks != be32_to_cpu(agf->agf_longest))
405 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
406 }
407 
408 /* Check the btree block counts in the AGF against the btrees. */
409 STATIC void
410 xchk_agf_xref_btreeblks(
411 	struct xfs_scrub	*sc)
412 {
413 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
414 	struct xfs_mount	*mp = sc->mp;
415 	xfs_agblock_t		blocks;
416 	xfs_agblock_t		btreeblks;
417 	int			error;
418 
419 	/* Check agf_rmap_blocks; set up for agf_btreeblks check */
420 	if (sc->sa.rmap_cur) {
421 		error = xfs_btree_count_blocks(sc->sa.rmap_cur, &blocks);
422 		if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
423 			return;
424 		btreeblks = blocks - 1;
425 		if (blocks != be32_to_cpu(agf->agf_rmap_blocks))
426 			xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
427 	} else {
428 		btreeblks = 0;
429 	}
430 
431 	/*
432 	 * No rmap cursor; we can't xref if we have the rmapbt feature.
433 	 * We also can't do it if we're missing the free space btree cursors.
434 	 */
435 	if ((xfs_sb_version_hasrmapbt(&mp->m_sb) && !sc->sa.rmap_cur) ||
436 	    !sc->sa.bno_cur || !sc->sa.cnt_cur)
437 		return;
438 
439 	/* Check agf_btreeblks */
440 	error = xfs_btree_count_blocks(sc->sa.bno_cur, &blocks);
441 	if (!xchk_should_check_xref(sc, &error, &sc->sa.bno_cur))
442 		return;
443 	btreeblks += blocks - 1;
444 
445 	error = xfs_btree_count_blocks(sc->sa.cnt_cur, &blocks);
446 	if (!xchk_should_check_xref(sc, &error, &sc->sa.cnt_cur))
447 		return;
448 	btreeblks += blocks - 1;
449 
450 	if (btreeblks != be32_to_cpu(agf->agf_btreeblks))
451 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
452 }
453 
454 /* Check agf_refcount_blocks against tree size */
455 static inline void
456 xchk_agf_xref_refcblks(
457 	struct xfs_scrub	*sc)
458 {
459 	struct xfs_agf		*agf = sc->sa.agf_bp->b_addr;
460 	xfs_agblock_t		blocks;
461 	int			error;
462 
463 	if (!sc->sa.refc_cur)
464 		return;
465 
466 	error = xfs_btree_count_blocks(sc->sa.refc_cur, &blocks);
467 	if (!xchk_should_check_xref(sc, &error, &sc->sa.refc_cur))
468 		return;
469 	if (blocks != be32_to_cpu(agf->agf_refcount_blocks))
470 		xchk_block_xref_set_corrupt(sc, sc->sa.agf_bp);
471 }
472 
473 /* Cross-reference with the other btrees. */
474 STATIC void
475 xchk_agf_xref(
476 	struct xfs_scrub	*sc)
477 {
478 	struct xfs_mount	*mp = sc->mp;
479 	xfs_agblock_t		agbno;
480 	int			error;
481 
482 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
483 		return;
484 
485 	agbno = XFS_AGF_BLOCK(mp);
486 
487 	error = xchk_ag_btcur_init(sc, &sc->sa);
488 	if (error)
489 		return;
490 
491 	xchk_xref_is_used_space(sc, agbno, 1);
492 	xchk_agf_xref_freeblks(sc);
493 	xchk_agf_xref_cntbt(sc);
494 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
495 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
496 	xchk_agf_xref_btreeblks(sc);
497 	xchk_xref_is_not_shared(sc, agbno, 1);
498 	xchk_agf_xref_refcblks(sc);
499 
500 	/* scrub teardown will take care of sc->sa for us */
501 }
502 
503 /* Scrub the AGF. */
504 int
505 xchk_agf(
506 	struct xfs_scrub	*sc)
507 {
508 	struct xfs_mount	*mp = sc->mp;
509 	struct xfs_agf		*agf;
510 	struct xfs_perag	*pag;
511 	xfs_agnumber_t		agno;
512 	xfs_agblock_t		agbno;
513 	xfs_agblock_t		eoag;
514 	xfs_agblock_t		agfl_first;
515 	xfs_agblock_t		agfl_last;
516 	xfs_agblock_t		agfl_count;
517 	xfs_agblock_t		fl_count;
518 	int			level;
519 	int			error = 0;
520 
521 	agno = sc->sa.agno = sc->sm->sm_agno;
522 	error = xchk_ag_read_headers(sc, agno, &sc->sa.agi_bp,
523 			&sc->sa.agf_bp, &sc->sa.agfl_bp);
524 	if (!xchk_process_error(sc, agno, XFS_AGF_BLOCK(sc->mp), &error))
525 		goto out;
526 	xchk_buffer_recheck(sc, sc->sa.agf_bp);
527 
528 	agf = sc->sa.agf_bp->b_addr;
529 
530 	/* Check the AG length */
531 	eoag = be32_to_cpu(agf->agf_length);
532 	if (eoag != xfs_ag_block_count(mp, agno))
533 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
534 
535 	/* Check the AGF btree roots and levels */
536 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_BNO]);
537 	if (!xfs_verify_agbno(mp, agno, agbno))
538 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
539 
540 	agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_CNT]);
541 	if (!xfs_verify_agbno(mp, agno, agbno))
542 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
543 
544 	level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
545 	if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
546 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
547 
548 	level = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
549 	if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
550 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
551 
552 	if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
553 		agbno = be32_to_cpu(agf->agf_roots[XFS_BTNUM_RMAP]);
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_RMAP]);
558 		if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
559 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
560 	}
561 
562 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
563 		agbno = be32_to_cpu(agf->agf_refcount_root);
564 		if (!xfs_verify_agbno(mp, agno, agbno))
565 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
566 
567 		level = be32_to_cpu(agf->agf_refcount_level);
568 		if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
569 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
570 	}
571 
572 	/* Check the AGFL counters */
573 	agfl_first = be32_to_cpu(agf->agf_flfirst);
574 	agfl_last = be32_to_cpu(agf->agf_fllast);
575 	agfl_count = be32_to_cpu(agf->agf_flcount);
576 	if (agfl_last > agfl_first)
577 		fl_count = agfl_last - agfl_first + 1;
578 	else
579 		fl_count = xfs_agfl_size(mp) - agfl_first + agfl_last + 1;
580 	if (agfl_count != 0 && fl_count != agfl_count)
581 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
582 
583 	/* Do the incore counters match? */
584 	pag = xfs_perag_get(mp, agno);
585 	if (pag->pagf_freeblks != be32_to_cpu(agf->agf_freeblks))
586 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
587 	if (pag->pagf_flcount != be32_to_cpu(agf->agf_flcount))
588 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
589 	if (pag->pagf_btreeblks != be32_to_cpu(agf->agf_btreeblks))
590 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
591 	xfs_perag_put(pag);
592 
593 	xchk_agf_xref(sc);
594 out:
595 	return error;
596 }
597 
598 /* AGFL */
599 
600 struct xchk_agfl_info {
601 	unsigned int		sz_entries;
602 	unsigned int		nr_entries;
603 	xfs_agblock_t		*entries;
604 	struct xfs_scrub	*sc;
605 };
606 
607 /* Cross-reference with the other btrees. */
608 STATIC void
609 xchk_agfl_block_xref(
610 	struct xfs_scrub	*sc,
611 	xfs_agblock_t		agbno)
612 {
613 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
614 		return;
615 
616 	xchk_xref_is_used_space(sc, agbno, 1);
617 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
618 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_AG);
619 	xchk_xref_is_not_shared(sc, agbno, 1);
620 }
621 
622 /* Scrub an AGFL block. */
623 STATIC int
624 xchk_agfl_block(
625 	struct xfs_mount	*mp,
626 	xfs_agblock_t		agbno,
627 	void			*priv)
628 {
629 	struct xchk_agfl_info	*sai = priv;
630 	struct xfs_scrub	*sc = sai->sc;
631 	xfs_agnumber_t		agno = sc->sa.agno;
632 
633 	if (xfs_verify_agbno(mp, agno, agbno) &&
634 	    sai->nr_entries < sai->sz_entries)
635 		sai->entries[sai->nr_entries++] = agbno;
636 	else
637 		xchk_block_set_corrupt(sc, sc->sa.agfl_bp);
638 
639 	xchk_agfl_block_xref(sc, agbno);
640 
641 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
642 		return -ECANCELED;
643 
644 	return 0;
645 }
646 
647 static int
648 xchk_agblock_cmp(
649 	const void		*pa,
650 	const void		*pb)
651 {
652 	const xfs_agblock_t	*a = pa;
653 	const xfs_agblock_t	*b = pb;
654 
655 	return (int)*a - (int)*b;
656 }
657 
658 /* Cross-reference with the other btrees. */
659 STATIC void
660 xchk_agfl_xref(
661 	struct xfs_scrub	*sc)
662 {
663 	struct xfs_mount	*mp = sc->mp;
664 	xfs_agblock_t		agbno;
665 	int			error;
666 
667 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
668 		return;
669 
670 	agbno = XFS_AGFL_BLOCK(mp);
671 
672 	error = xchk_ag_btcur_init(sc, &sc->sa);
673 	if (error)
674 		return;
675 
676 	xchk_xref_is_used_space(sc, agbno, 1);
677 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
678 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
679 	xchk_xref_is_not_shared(sc, agbno, 1);
680 
681 	/*
682 	 * Scrub teardown will take care of sc->sa for us.  Leave sc->sa
683 	 * active so that the agfl block xref can use it too.
684 	 */
685 }
686 
687 /* Scrub the AGFL. */
688 int
689 xchk_agfl(
690 	struct xfs_scrub	*sc)
691 {
692 	struct xchk_agfl_info	sai;
693 	struct xfs_agf		*agf;
694 	xfs_agnumber_t		agno;
695 	unsigned int		agflcount;
696 	unsigned int		i;
697 	int			error;
698 
699 	agno = sc->sa.agno = sc->sm->sm_agno;
700 	error = xchk_ag_read_headers(sc, agno, &sc->sa.agi_bp,
701 			&sc->sa.agf_bp, &sc->sa.agfl_bp);
702 	if (!xchk_process_error(sc, agno, XFS_AGFL_BLOCK(sc->mp), &error))
703 		goto out;
704 	if (!sc->sa.agf_bp)
705 		return -EFSCORRUPTED;
706 	xchk_buffer_recheck(sc, sc->sa.agfl_bp);
707 
708 	xchk_agfl_xref(sc);
709 
710 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
711 		goto out;
712 
713 	/* Allocate buffer to ensure uniqueness of AGFL entries. */
714 	agf = sc->sa.agf_bp->b_addr;
715 	agflcount = be32_to_cpu(agf->agf_flcount);
716 	if (agflcount > xfs_agfl_size(sc->mp)) {
717 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
718 		goto out;
719 	}
720 	memset(&sai, 0, sizeof(sai));
721 	sai.sc = sc;
722 	sai.sz_entries = agflcount;
723 	sai.entries = kmem_zalloc(sizeof(xfs_agblock_t) * agflcount,
724 			KM_MAYFAIL);
725 	if (!sai.entries) {
726 		error = -ENOMEM;
727 		goto out;
728 	}
729 
730 	/* Check the blocks in the AGFL. */
731 	error = xfs_agfl_walk(sc->mp, sc->sa.agf_bp->b_addr,
732 			sc->sa.agfl_bp, xchk_agfl_block, &sai);
733 	if (error == -ECANCELED) {
734 		error = 0;
735 		goto out_free;
736 	}
737 	if (error)
738 		goto out_free;
739 
740 	if (agflcount != sai.nr_entries) {
741 		xchk_block_set_corrupt(sc, sc->sa.agf_bp);
742 		goto out_free;
743 	}
744 
745 	/* Sort entries, check for duplicates. */
746 	sort(sai.entries, sai.nr_entries, sizeof(sai.entries[0]),
747 			xchk_agblock_cmp, NULL);
748 	for (i = 1; i < sai.nr_entries; i++) {
749 		if (sai.entries[i] == sai.entries[i - 1]) {
750 			xchk_block_set_corrupt(sc, sc->sa.agf_bp);
751 			break;
752 		}
753 	}
754 
755 out_free:
756 	kmem_free(sai.entries);
757 out:
758 	return error;
759 }
760 
761 /* AGI */
762 
763 /* Check agi_count/agi_freecount */
764 static inline void
765 xchk_agi_xref_icounts(
766 	struct xfs_scrub	*sc)
767 {
768 	struct xfs_agi		*agi = sc->sa.agi_bp->b_addr;
769 	xfs_agino_t		icount;
770 	xfs_agino_t		freecount;
771 	int			error;
772 
773 	if (!sc->sa.ino_cur)
774 		return;
775 
776 	error = xfs_ialloc_count_inodes(sc->sa.ino_cur, &icount, &freecount);
777 	if (!xchk_should_check_xref(sc, &error, &sc->sa.ino_cur))
778 		return;
779 	if (be32_to_cpu(agi->agi_count) != icount ||
780 	    be32_to_cpu(agi->agi_freecount) != freecount)
781 		xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
782 }
783 
784 /* Check agi_[fi]blocks against tree size */
785 static inline void
786 xchk_agi_xref_fiblocks(
787 	struct xfs_scrub	*sc)
788 {
789 	struct xfs_agi		*agi = sc->sa.agi_bp->b_addr;
790 	xfs_agblock_t		blocks;
791 	int			error = 0;
792 
793 	if (!xfs_sb_version_hasinobtcounts(&sc->mp->m_sb))
794 		return;
795 
796 	if (sc->sa.ino_cur) {
797 		error = xfs_btree_count_blocks(sc->sa.ino_cur, &blocks);
798 		if (!xchk_should_check_xref(sc, &error, &sc->sa.ino_cur))
799 			return;
800 		if (blocks != be32_to_cpu(agi->agi_iblocks))
801 			xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
802 	}
803 
804 	if (sc->sa.fino_cur) {
805 		error = xfs_btree_count_blocks(sc->sa.fino_cur, &blocks);
806 		if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur))
807 			return;
808 		if (blocks != be32_to_cpu(agi->agi_fblocks))
809 			xchk_block_xref_set_corrupt(sc, sc->sa.agi_bp);
810 	}
811 }
812 
813 /* Cross-reference with the other btrees. */
814 STATIC void
815 xchk_agi_xref(
816 	struct xfs_scrub	*sc)
817 {
818 	struct xfs_mount	*mp = sc->mp;
819 	xfs_agblock_t		agbno;
820 	int			error;
821 
822 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
823 		return;
824 
825 	agbno = XFS_AGI_BLOCK(mp);
826 
827 	error = xchk_ag_btcur_init(sc, &sc->sa);
828 	if (error)
829 		return;
830 
831 	xchk_xref_is_used_space(sc, agbno, 1);
832 	xchk_xref_is_not_inode_chunk(sc, agbno, 1);
833 	xchk_agi_xref_icounts(sc);
834 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
835 	xchk_xref_is_not_shared(sc, agbno, 1);
836 	xchk_agi_xref_fiblocks(sc);
837 
838 	/* scrub teardown will take care of sc->sa for us */
839 }
840 
841 /* Scrub the AGI. */
842 int
843 xchk_agi(
844 	struct xfs_scrub	*sc)
845 {
846 	struct xfs_mount	*mp = sc->mp;
847 	struct xfs_agi		*agi;
848 	struct xfs_perag	*pag;
849 	xfs_agnumber_t		agno;
850 	xfs_agblock_t		agbno;
851 	xfs_agblock_t		eoag;
852 	xfs_agino_t		agino;
853 	xfs_agino_t		first_agino;
854 	xfs_agino_t		last_agino;
855 	xfs_agino_t		icount;
856 	int			i;
857 	int			level;
858 	int			error = 0;
859 
860 	agno = sc->sa.agno = sc->sm->sm_agno;
861 	error = xchk_ag_read_headers(sc, agno, &sc->sa.agi_bp,
862 			&sc->sa.agf_bp, &sc->sa.agfl_bp);
863 	if (!xchk_process_error(sc, agno, XFS_AGI_BLOCK(sc->mp), &error))
864 		goto out;
865 	xchk_buffer_recheck(sc, sc->sa.agi_bp);
866 
867 	agi = sc->sa.agi_bp->b_addr;
868 
869 	/* Check the AG length */
870 	eoag = be32_to_cpu(agi->agi_length);
871 	if (eoag != xfs_ag_block_count(mp, agno))
872 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
873 
874 	/* Check btree roots and levels */
875 	agbno = be32_to_cpu(agi->agi_root);
876 	if (!xfs_verify_agbno(mp, agno, agbno))
877 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
878 
879 	level = be32_to_cpu(agi->agi_level);
880 	if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
881 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
882 
883 	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
884 		agbno = be32_to_cpu(agi->agi_free_root);
885 		if (!xfs_verify_agbno(mp, agno, agbno))
886 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
887 
888 		level = be32_to_cpu(agi->agi_free_level);
889 		if (level <= 0 || level > XFS_BTREE_MAXLEVELS)
890 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
891 	}
892 
893 	/* Check inode counters */
894 	xfs_agino_range(mp, agno, &first_agino, &last_agino);
895 	icount = be32_to_cpu(agi->agi_count);
896 	if (icount > last_agino - first_agino + 1 ||
897 	    icount < be32_to_cpu(agi->agi_freecount))
898 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
899 
900 	/* Check inode pointers */
901 	agino = be32_to_cpu(agi->agi_newino);
902 	if (!xfs_verify_agino_or_null(mp, agno, agino))
903 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
904 
905 	agino = be32_to_cpu(agi->agi_dirino);
906 	if (!xfs_verify_agino_or_null(mp, agno, agino))
907 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
908 
909 	/* Check unlinked inode buckets */
910 	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
911 		agino = be32_to_cpu(agi->agi_unlinked[i]);
912 		if (!xfs_verify_agino_or_null(mp, agno, agino))
913 			xchk_block_set_corrupt(sc, sc->sa.agi_bp);
914 	}
915 
916 	if (agi->agi_pad32 != cpu_to_be32(0))
917 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
918 
919 	/* Do the incore counters match? */
920 	pag = xfs_perag_get(mp, agno);
921 	if (pag->pagi_count != be32_to_cpu(agi->agi_count))
922 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
923 	if (pag->pagi_freecount != be32_to_cpu(agi->agi_freecount))
924 		xchk_block_set_corrupt(sc, sc->sa.agi_bp);
925 	xfs_perag_put(pag);
926 
927 	xchk_agi_xref(sc);
928 out:
929 	return error;
930 }
931