xref: /linux/fs/xfs/scrub/quota_repair.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2018-2023 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_defer.h"
13 #include "xfs_btree.h"
14 #include "xfs_bit.h"
15 #include "xfs_format.h"
16 #include "xfs_log_format.h"
17 #include "xfs_trans.h"
18 #include "xfs_sb.h"
19 #include "xfs_inode.h"
20 #include "xfs_inode_fork.h"
21 #include "xfs_alloc.h"
22 #include "xfs_bmap.h"
23 #include "xfs_quota.h"
24 #include "xfs_qm.h"
25 #include "xfs_dquot.h"
26 #include "xfs_dquot_item.h"
27 #include "xfs_reflink.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_trans_space.h"
30 #include "scrub/xfs_scrub.h"
31 #include "scrub/scrub.h"
32 #include "scrub/common.h"
33 #include "scrub/quota.h"
34 #include "scrub/trace.h"
35 #include "scrub/repair.h"
36 
37 /*
38  * Quota Repair
39  * ============
40  *
41  * Quota repairs are fairly simplistic; we fix everything that the dquot
42  * verifiers complain about, cap any counters or limits that make no sense,
43  * and schedule a quotacheck if we had to fix anything.  We also repair any
44  * data fork extent records that don't apply to metadata files.
45  */
46 
47 struct xrep_quota_info {
48 	struct xfs_scrub	*sc;
49 	bool			need_quotacheck;
50 };
51 
52 /*
53  * Allocate a new block into a sparse hole in the quota file backing this
54  * dquot, initialize the block, and commit the whole mess.
55  */
56 STATIC int
57 xrep_quota_item_fill_bmap_hole(
58 	struct xfs_scrub	*sc,
59 	struct xfs_dquot	*dq,
60 	struct xfs_bmbt_irec	*irec)
61 {
62 	struct xfs_buf		*bp;
63 	struct xfs_mount	*mp = sc->mp;
64 	int			nmaps = 1;
65 	int			error;
66 
67 	xfs_trans_ijoin(sc->tp, sc->ip, 0);
68 
69 	/* Map a block into the file. */
70 	error = xfs_trans_reserve_more(sc->tp, XFS_QM_DQALLOC_SPACE_RES(mp),
71 			0);
72 	if (error)
73 		return error;
74 
75 	error = xfs_bmapi_write(sc->tp, sc->ip, dq->q_fileoffset,
76 			XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, 0,
77 			irec, &nmaps);
78 	if (error)
79 		return error;
80 	if (nmaps != 1)
81 		return -ENOSPC;
82 
83 	dq->q_blkno = XFS_FSB_TO_DADDR(mp, irec->br_startblock);
84 
85 	trace_xrep_dquot_item_fill_bmap_hole(sc->mp, dq->q_type, dq->q_id);
86 
87 	/* Initialize the new block. */
88 	error = xfs_trans_get_buf(sc->tp, mp->m_ddev_targp, dq->q_blkno,
89 			mp->m_quotainfo->qi_dqchunklen, 0, &bp);
90 	if (error)
91 		return error;
92 	bp->b_ops = &xfs_dquot_buf_ops;
93 
94 	xfs_qm_init_dquot_blk(sc->tp, dq->q_id, dq->q_type, bp);
95 	xfs_buf_set_ref(bp, XFS_DQUOT_REF);
96 
97 	/*
98 	 * Finish the mapping transactions and roll one more time to
99 	 * disconnect sc->ip from sc->tp.
100 	 */
101 	error = xrep_defer_finish(sc);
102 	if (error)
103 		return error;
104 	return xfs_trans_roll(&sc->tp);
105 }
106 
107 /* Make sure there's a written block backing this dquot */
108 STATIC int
109 xrep_quota_item_bmap(
110 	struct xfs_scrub	*sc,
111 	struct xfs_dquot	*dq,
112 	bool			*dirty)
113 {
114 	struct xfs_bmbt_irec	irec;
115 	struct xfs_mount	*mp = sc->mp;
116 	struct xfs_quotainfo	*qi = mp->m_quotainfo;
117 	xfs_fileoff_t		offset = dq->q_id / qi->qi_dqperchunk;
118 	int			nmaps = 1;
119 	int			error;
120 
121 	/* The computed file offset should always be valid. */
122 	if (!xfs_verify_fileoff(mp, offset)) {
123 		ASSERT(xfs_verify_fileoff(mp, offset));
124 		return -EFSCORRUPTED;
125 	}
126 	dq->q_fileoffset = offset;
127 
128 	error = xfs_bmapi_read(sc->ip, offset, 1, &irec, &nmaps, 0);
129 	if (error)
130 		return error;
131 
132 	if (nmaps < 1 || !xfs_bmap_is_real_extent(&irec)) {
133 		/* Hole/delalloc extent; allocate a real block. */
134 		error = xrep_quota_item_fill_bmap_hole(sc, dq, &irec);
135 		if (error)
136 			return error;
137 	} else if (irec.br_state != XFS_EXT_NORM) {
138 		/* Unwritten extent, which we already took care of? */
139 		ASSERT(irec.br_state == XFS_EXT_NORM);
140 		return -EFSCORRUPTED;
141 	} else if (dq->q_blkno != XFS_FSB_TO_DADDR(mp, irec.br_startblock)) {
142 		/*
143 		 * If the cached daddr is incorrect, repair probably punched a
144 		 * hole out of the quota file and filled it back in with a new
145 		 * block.  Update the block mapping in the dquot.
146 		 */
147 		dq->q_blkno = XFS_FSB_TO_DADDR(mp, irec.br_startblock);
148 	}
149 
150 	*dirty = true;
151 	return 0;
152 }
153 
154 /* Reset quota timers if incorrectly set. */
155 static inline void
156 xrep_quota_item_timer(
157 	struct xfs_scrub		*sc,
158 	const struct xfs_dquot_res	*res,
159 	bool				*dirty)
160 {
161 	if ((res->softlimit && res->count > res->softlimit) ||
162 	    (res->hardlimit && res->count > res->hardlimit)) {
163 		if (!res->timer)
164 			*dirty = true;
165 	} else {
166 		if (res->timer)
167 			*dirty = true;
168 	}
169 }
170 
171 /* Scrub the fields in an individual quota item. */
172 STATIC int
173 xrep_quota_item(
174 	struct xrep_quota_info	*rqi,
175 	struct xfs_dquot	*dq)
176 {
177 	struct xfs_scrub	*sc = rqi->sc;
178 	struct xfs_mount	*mp = sc->mp;
179 	xfs_ino_t		fs_icount;
180 	bool			dirty = false;
181 	int			error = 0;
182 
183 	/* Last chance to abort before we start committing fixes. */
184 	if (xchk_should_terminate(sc, &error))
185 		return error;
186 
187 	/*
188 	 * We might need to fix holes in the bmap record for the storage
189 	 * backing this dquot, so we need to lock the dquot and the quota file.
190 	 * dqiterate gave us a locked dquot, so drop the dquot lock to get the
191 	 * ILOCK_EXCL.
192 	 */
193 	xfs_dqunlock(dq);
194 	xchk_ilock(sc, XFS_ILOCK_EXCL);
195 	xfs_dqlock(dq);
196 
197 	error = xrep_quota_item_bmap(sc, dq, &dirty);
198 	xchk_iunlock(sc, XFS_ILOCK_EXCL);
199 	if (error)
200 		return error;
201 
202 	/* Check the limits. */
203 	if (dq->q_blk.softlimit > dq->q_blk.hardlimit) {
204 		dq->q_blk.softlimit = dq->q_blk.hardlimit;
205 		dirty = true;
206 	}
207 
208 	if (dq->q_ino.softlimit > dq->q_ino.hardlimit) {
209 		dq->q_ino.softlimit = dq->q_ino.hardlimit;
210 		dirty = true;
211 	}
212 
213 	if (dq->q_rtb.softlimit > dq->q_rtb.hardlimit) {
214 		dq->q_rtb.softlimit = dq->q_rtb.hardlimit;
215 		dirty = true;
216 	}
217 
218 	/*
219 	 * Check that usage doesn't exceed physical limits.  However, on
220 	 * a reflink filesystem we're allowed to exceed physical space
221 	 * if there are no quota limits.  We don't know what the real number
222 	 * is, but we can make quotacheck find out for us.
223 	 */
224 	if (!xfs_has_reflink(mp) && dq->q_blk.count > mp->m_sb.sb_dblocks) {
225 		dq->q_blk.reserved -= dq->q_blk.count;
226 		dq->q_blk.reserved += mp->m_sb.sb_dblocks;
227 		dq->q_blk.count = mp->m_sb.sb_dblocks;
228 		rqi->need_quotacheck = true;
229 		dirty = true;
230 	}
231 	fs_icount = percpu_counter_sum(&mp->m_icount);
232 	if (dq->q_ino.count > fs_icount) {
233 		dq->q_ino.reserved -= dq->q_ino.count;
234 		dq->q_ino.reserved += fs_icount;
235 		dq->q_ino.count = fs_icount;
236 		rqi->need_quotacheck = true;
237 		dirty = true;
238 	}
239 	if (dq->q_rtb.count > mp->m_sb.sb_rblocks) {
240 		dq->q_rtb.reserved -= dq->q_rtb.count;
241 		dq->q_rtb.reserved += mp->m_sb.sb_rblocks;
242 		dq->q_rtb.count = mp->m_sb.sb_rblocks;
243 		rqi->need_quotacheck = true;
244 		dirty = true;
245 	}
246 
247 	xrep_quota_item_timer(sc, &dq->q_blk, &dirty);
248 	xrep_quota_item_timer(sc, &dq->q_ino, &dirty);
249 	xrep_quota_item_timer(sc, &dq->q_rtb, &dirty);
250 
251 	if (!dirty)
252 		return 0;
253 
254 	trace_xrep_dquot_item(sc->mp, dq->q_type, dq->q_id);
255 
256 	dq->q_flags |= XFS_DQFLAG_DIRTY;
257 	xfs_trans_dqjoin(sc->tp, dq);
258 	if (dq->q_id) {
259 		xfs_qm_adjust_dqlimits(dq);
260 		xfs_qm_adjust_dqtimers(dq);
261 	}
262 	xfs_trans_log_dquot(sc->tp, dq);
263 	error = xfs_trans_roll(&sc->tp);
264 	xfs_dqlock(dq);
265 	return error;
266 }
267 
268 /* Fix a quota timer so that we can pass the verifier. */
269 STATIC void
270 xrep_quota_fix_timer(
271 	struct xfs_mount	*mp,
272 	const struct xfs_disk_dquot *ddq,
273 	__be64			softlimit,
274 	__be64			countnow,
275 	__be32			*timer,
276 	time64_t		timelimit)
277 {
278 	uint64_t		soft = be64_to_cpu(softlimit);
279 	uint64_t		count = be64_to_cpu(countnow);
280 	time64_t		new_timer;
281 	uint32_t		t;
282 
283 	if (!soft || count <= soft || *timer != 0)
284 		return;
285 
286 	new_timer = xfs_dquot_set_timeout(mp,
287 				ktime_get_real_seconds() + timelimit);
288 	if (ddq->d_type & XFS_DQTYPE_BIGTIME)
289 		t = xfs_dq_unix_to_bigtime(new_timer);
290 	else
291 		t = new_timer;
292 
293 	*timer = cpu_to_be32(t);
294 }
295 
296 /* Fix anything the verifiers complain about. */
297 STATIC int
298 xrep_quota_block(
299 	struct xfs_scrub	*sc,
300 	xfs_daddr_t		daddr,
301 	xfs_dqtype_t		dqtype,
302 	xfs_dqid_t		id)
303 {
304 	struct xfs_dqblk	*dqblk;
305 	struct xfs_disk_dquot	*ddq;
306 	struct xfs_quotainfo	*qi = sc->mp->m_quotainfo;
307 	struct xfs_def_quota	*defq = xfs_get_defquota(qi, dqtype);
308 	struct xfs_buf		*bp = NULL;
309 	enum xfs_blft		buftype = 0;
310 	int			i;
311 	int			error;
312 
313 	error = xfs_trans_read_buf(sc->mp, sc->tp, sc->mp->m_ddev_targp, daddr,
314 			qi->qi_dqchunklen, 0, &bp, &xfs_dquot_buf_ops);
315 	switch (error) {
316 	case -EFSBADCRC:
317 	case -EFSCORRUPTED:
318 		/* Failed verifier, retry read with no ops. */
319 		error = xfs_trans_read_buf(sc->mp, sc->tp,
320 				sc->mp->m_ddev_targp, daddr, qi->qi_dqchunklen,
321 				0, &bp, NULL);
322 		if (error)
323 			return error;
324 		break;
325 	case 0:
326 		dqblk = bp->b_addr;
327 		ddq = &dqblk[0].dd_diskdq;
328 
329 		/*
330 		 * If there's nothing that would impede a dqiterate, we're
331 		 * done.
332 		 */
333 		if ((ddq->d_type & XFS_DQTYPE_REC_MASK) != dqtype ||
334 		    id == be32_to_cpu(ddq->d_id)) {
335 			xfs_trans_brelse(sc->tp, bp);
336 			return 0;
337 		}
338 		break;
339 	default:
340 		return error;
341 	}
342 
343 	/* Something's wrong with the block, fix the whole thing. */
344 	dqblk = bp->b_addr;
345 	bp->b_ops = &xfs_dquot_buf_ops;
346 	for (i = 0; i < qi->qi_dqperchunk; i++, dqblk++) {
347 		ddq = &dqblk->dd_diskdq;
348 
349 		trace_xrep_disk_dquot(sc->mp, dqtype, id + i);
350 
351 		ddq->d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
352 		ddq->d_version = XFS_DQUOT_VERSION;
353 		ddq->d_type = dqtype;
354 		ddq->d_id = cpu_to_be32(id + i);
355 
356 		if (xfs_has_bigtime(sc->mp) && ddq->d_id)
357 			ddq->d_type |= XFS_DQTYPE_BIGTIME;
358 
359 		xrep_quota_fix_timer(sc->mp, ddq, ddq->d_blk_softlimit,
360 				ddq->d_bcount, &ddq->d_btimer,
361 				defq->blk.time);
362 
363 		xrep_quota_fix_timer(sc->mp, ddq, ddq->d_ino_softlimit,
364 				ddq->d_icount, &ddq->d_itimer,
365 				defq->ino.time);
366 
367 		xrep_quota_fix_timer(sc->mp, ddq, ddq->d_rtb_softlimit,
368 				ddq->d_rtbcount, &ddq->d_rtbtimer,
369 				defq->rtb.time);
370 
371 		/* We only support v5 filesystems so always set these. */
372 		uuid_copy(&dqblk->dd_uuid, &sc->mp->m_sb.sb_meta_uuid);
373 		xfs_update_cksum((char *)dqblk, sizeof(struct xfs_dqblk),
374 				 XFS_DQUOT_CRC_OFF);
375 		dqblk->dd_lsn = 0;
376 	}
377 	switch (dqtype) {
378 	case XFS_DQTYPE_USER:
379 		buftype = XFS_BLFT_UDQUOT_BUF;
380 		break;
381 	case XFS_DQTYPE_GROUP:
382 		buftype = XFS_BLFT_GDQUOT_BUF;
383 		break;
384 	case XFS_DQTYPE_PROJ:
385 		buftype = XFS_BLFT_PDQUOT_BUF;
386 		break;
387 	}
388 	xfs_trans_buf_set_type(sc->tp, bp, buftype);
389 	xfs_trans_log_buf(sc->tp, bp, 0, BBTOB(bp->b_length) - 1);
390 	return xrep_roll_trans(sc);
391 }
392 
393 /*
394  * Repair a quota file's data fork.  The function returns with the inode
395  * joined.
396  */
397 STATIC int
398 xrep_quota_data_fork(
399 	struct xfs_scrub	*sc,
400 	xfs_dqtype_t		dqtype)
401 {
402 	struct xfs_bmbt_irec	irec = { 0 };
403 	struct xfs_iext_cursor	icur;
404 	struct xfs_quotainfo	*qi = sc->mp->m_quotainfo;
405 	struct xfs_ifork	*ifp;
406 	xfs_fileoff_t		max_dqid_off;
407 	xfs_fileoff_t		off;
408 	xfs_fsblock_t		fsbno;
409 	bool			truncate = false;
410 	bool			joined = false;
411 	int			error = 0;
412 
413 	error = xrep_metadata_inode_forks(sc);
414 	if (error)
415 		goto out;
416 
417 	/* Check for data fork problems that apply only to quota files. */
418 	max_dqid_off = XFS_DQ_ID_MAX / qi->qi_dqperchunk;
419 	ifp = xfs_ifork_ptr(sc->ip, XFS_DATA_FORK);
420 	for_each_xfs_iext(ifp, &icur, &irec) {
421 		if (isnullstartblock(irec.br_startblock)) {
422 			error = -EFSCORRUPTED;
423 			goto out;
424 		}
425 
426 		if (irec.br_startoff > max_dqid_off ||
427 		    irec.br_startoff + irec.br_blockcount - 1 > max_dqid_off) {
428 			truncate = true;
429 			break;
430 		}
431 
432 		/* Convert unwritten extents to real ones. */
433 		if (irec.br_state == XFS_EXT_UNWRITTEN) {
434 			struct xfs_bmbt_irec	nrec;
435 			int			nmap = 1;
436 
437 			if (!joined) {
438 				xfs_trans_ijoin(sc->tp, sc->ip, 0);
439 				joined = true;
440 			}
441 
442 			error = xfs_bmapi_write(sc->tp, sc->ip,
443 					irec.br_startoff, irec.br_blockcount,
444 					XFS_BMAPI_CONVERT, 0, &nrec, &nmap);
445 			if (error)
446 				goto out;
447 			if (nmap != 1) {
448 				error = -ENOSPC;
449 				goto out;
450 			}
451 			ASSERT(nrec.br_startoff == irec.br_startoff);
452 			ASSERT(nrec.br_blockcount == irec.br_blockcount);
453 
454 			error = xfs_defer_finish(&sc->tp);
455 			if (error)
456 				goto out;
457 		}
458 	}
459 
460 	if (!joined) {
461 		xfs_trans_ijoin(sc->tp, sc->ip, 0);
462 		joined = true;
463 	}
464 
465 	if (truncate) {
466 		/* Erase everything after the block containing the max dquot */
467 		error = xfs_bunmapi_range(&sc->tp, sc->ip, 0,
468 				max_dqid_off * sc->mp->m_sb.sb_blocksize,
469 				XFS_MAX_FILEOFF);
470 		if (error)
471 			goto out;
472 
473 		/* Remove all CoW reservations. */
474 		error = xfs_reflink_cancel_cow_blocks(sc->ip, &sc->tp, 0,
475 				XFS_MAX_FILEOFF, true);
476 		if (error)
477 			goto out;
478 		sc->ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
479 
480 		/*
481 		 * Always re-log the inode so that our permanent transaction
482 		 * can keep on rolling it forward in the log.
483 		 */
484 		xfs_trans_log_inode(sc->tp, sc->ip, XFS_ILOG_CORE);
485 	}
486 
487 	/* Now go fix anything that fails the verifiers. */
488 	for_each_xfs_iext(ifp, &icur, &irec) {
489 		for (fsbno = irec.br_startblock, off = irec.br_startoff;
490 		     fsbno < irec.br_startblock + irec.br_blockcount;
491 		     fsbno += XFS_DQUOT_CLUSTER_SIZE_FSB,
492 				off += XFS_DQUOT_CLUSTER_SIZE_FSB) {
493 			error = xrep_quota_block(sc,
494 					XFS_FSB_TO_DADDR(sc->mp, fsbno),
495 					dqtype, off * qi->qi_dqperchunk);
496 			if (error)
497 				goto out;
498 		}
499 	}
500 
501 out:
502 	return error;
503 }
504 
505 /*
506  * Go fix anything in the quota items that we could have been mad about.  Now
507  * that we've checked the quota inode data fork we have to drop ILOCK_EXCL to
508  * use the regular dquot functions.
509  */
510 STATIC int
511 xrep_quota_problems(
512 	struct xfs_scrub	*sc,
513 	xfs_dqtype_t		dqtype)
514 {
515 	struct xchk_dqiter	cursor = { };
516 	struct xrep_quota_info	rqi = { .sc = sc };
517 	struct xfs_dquot	*dq;
518 	int			error;
519 
520 	xchk_dqiter_init(&cursor, sc, dqtype);
521 	while ((error = xchk_dquot_iter(&cursor, &dq)) == 1) {
522 		error = xrep_quota_item(&rqi, dq);
523 		xfs_qm_dqput(dq);
524 		if (error)
525 			break;
526 	}
527 	if (error)
528 		return error;
529 
530 	/* Make a quotacheck happen. */
531 	if (rqi.need_quotacheck)
532 		xrep_force_quotacheck(sc, dqtype);
533 	return 0;
534 }
535 
536 /* Repair all of a quota type's items. */
537 int
538 xrep_quota(
539 	struct xfs_scrub	*sc)
540 {
541 	xfs_dqtype_t		dqtype;
542 	int			error;
543 
544 	dqtype = xchk_quota_to_dqtype(sc);
545 
546 	/*
547 	 * Re-take the ILOCK so that we can fix any problems that we found
548 	 * with the data fork mappings, or with the dquot bufs themselves.
549 	 */
550 	if (!(sc->ilock_flags & XFS_ILOCK_EXCL))
551 		xchk_ilock(sc, XFS_ILOCK_EXCL);
552 	error = xrep_quota_data_fork(sc, dqtype);
553 	if (error)
554 		return error;
555 
556 	/*
557 	 * Finish deferred items and roll the transaction to unjoin the quota
558 	 * inode from transaction so that we can unlock the quota inode; we
559 	 * play only with dquots from now on.
560 	 */
561 	error = xrep_defer_finish(sc);
562 	if (error)
563 		return error;
564 	error = xfs_trans_roll(&sc->tp);
565 	if (error)
566 		return error;
567 	xchk_iunlock(sc, sc->ilock_flags);
568 
569 	/* Fix anything the dquot verifiers don't complain about. */
570 	error = xrep_quota_problems(sc, dqtype);
571 	if (error)
572 		return error;
573 
574 	return xrep_trans_commit(sc);
575 }
576