1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (c) 2020-2024 Oracle. All Rights Reserved.
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_log_format.h"
13 #include "xfs_trans.h"
14 #include "xfs_inode.h"
15 #include "xfs_quota.h"
17 #include "xfs_icache.h"
18 #include "xfs_bmap_util.h"
19 #include "xfs_ialloc.h"
21 #include "scrub/scrub.h"
22 #include "scrub/common.h"
23 #include "scrub/repair.h"
24 #include "scrub/xfile.h"
25 #include "scrub/xfarray.h"
26 #include "scrub/iscan.h"
27 #include "scrub/quota.h"
28 #include "scrub/quotacheck.h"
29 #include "scrub/trace.h"
35 * Quota counters are "summary" metadata, in the sense that they are computed
36 * as the summation of the block usage counts for every file on the filesystem.
37 * Therefore, we compute the correct icount, bcount, and rtbcount values by
38 * creating a shadow quota counter structure and walking every inode.
41 /* Track the quota deltas for a dquot in a transaction. */
42 struct xqcheck_dqtrx {
49 int64_t delbcnt_delta;
51 int64_t rtbcount_delta;
55 #define XQCHECK_MAX_NR_DQTRXS (XFS_QM_TRANS_DQTYPES * XFS_QM_TRANS_MAXDQS)
58 * Track the quota deltas for all dquots attached to a transaction if the
59 * quota deltas are being applied to an inode that we already scanned.
61 struct xqcheck_dqacct {
62 struct rhash_head hash;
64 struct xqcheck_dqtrx dqtrx[XQCHECK_MAX_NR_DQTRXS];
65 unsigned int refcount;
68 /* Free a shadow dquot accounting structure. */
74 struct xqcheck_dqacct *dqa = ptr;
79 /* Set us up to scrub quota counters. */
81 xchk_setup_quotacheck(
84 if (!XFS_IS_QUOTA_ON(sc->mp))
87 xchk_fsgates_enable(sc, XCHK_FSGATES_QUOTA);
89 sc->buf = kzalloc(sizeof(struct xqcheck), XCHK_GFP_FLAGS);
93 return xchk_setup_fs(sc);
97 * Part 1: Collecting dquot resource usage counts. For each xfs_dquot attached
98 * to each inode, we create a shadow dquot, and compute the inode count and add
99 * the data/rt block usage from what we see.
101 * To avoid false corruption reports in part 2, any failure in this part must
102 * set the INCOMPLETE flag even when a negative errno is returned. This care
103 * must be taken with certain errno values (i.e. EFSBADCRC, EFSCORRUPTED,
104 * ECANCELED) that are absorbed into a scrub state flag update by
105 * xchk_*_process_error. Scrub and repair share the same incore data
106 * structures, so the INCOMPLETE flag is critical to prevent a repair based on
107 * insufficient information.
109 * Because we are scanning a live filesystem, it's possible that another thread
110 * will try to update the quota counters for an inode that we've already
111 * scanned. This will cause our counts to be incorrect. Therefore, we hook
112 * the live transaction code in two places: (1) when the callers update the
113 * per-transaction dqtrx structure to log quota counter updates; and (2) when
114 * transaction commit actually logs those updates to the incore dquot. By
115 * shadowing transaction updates in this manner, live quotacheck can ensure
116 * by locking the dquot and the shadow structure that its own copies are not
117 * out of date. Because the hook code runs in a different process context from
118 * the scrub code and the scrub state flags are not accessed atomically,
119 * failures in the hook code must abort the iscan and the scrubber must notice
120 * the aborted scan and set the incomplete flag.
122 * Note that we use srcu notifier hooks to minimize the overhead when live
123 * quotacheck is /not/ running.
126 /* Update an incore dquot counter information from a live update. */
128 xqcheck_update_incore_counts(
130 struct xfarray *counts,
136 struct xqcheck_dquot xcdq;
139 error = xfarray_load_sparse(counts, id, &xcdq);
143 xcdq.flags |= XQCHECK_DQUOT_WRITTEN;
144 xcdq.icount += inodes;
145 xcdq.bcount += nblks;
146 xcdq.rtbcount += rtblks;
148 error = xfarray_store(counts, id, &xcdq);
149 if (error == -EFBIG) {
151 * EFBIG means we tried to store data at too high a byte offset
152 * in the sparse array. IOWs, we cannot complete the check and
153 * must notify userspace that the check was incomplete.
160 /* Decide if this is the shadow dquot accounting structure for a transaction. */
162 xqcheck_dqacct_obj_cmpfn(
163 struct rhashtable_compare_arg *arg,
166 const uintptr_t *tx_idp = arg->key;
167 const struct xqcheck_dqacct *dqa = obj;
169 if (dqa->tx_id != *tx_idp)
174 static const struct rhashtable_params xqcheck_dqacct_hash_params = {
176 .key_len = sizeof(uintptr_t),
177 .key_offset = offsetof(struct xqcheck_dqacct, tx_id),
178 .head_offset = offsetof(struct xqcheck_dqacct, hash),
179 .automatic_shrinking = true,
180 .obj_cmpfn = xqcheck_dqacct_obj_cmpfn,
183 /* Find a shadow dqtrx slot for the given dquot. */
184 STATIC struct xqcheck_dqtrx *
186 struct xqcheck_dqacct *dqa,
192 for (i = 0; i < XQCHECK_MAX_NR_DQTRXS; i++) {
193 if (dqa->dqtrx[i].q_type == 0 ||
194 (dqa->dqtrx[i].q_type == q_type &&
195 dqa->dqtrx[i].q_id == q_id))
196 return &dqa->dqtrx[i];
203 * Create and fill out a quota delta tracking structure to shadow the updates
204 * going on in the regular quota code.
207 xqcheck_mod_live_ino_dqtrx(
208 struct notifier_block *nb,
209 unsigned long action,
212 struct xfs_mod_ino_dqtrx_params *p = data;
214 struct xqcheck_dqacct *dqa;
215 struct xqcheck_dqtrx *dqtrx;
218 xqc = container_of(nb, struct xqcheck, qhook.mod_hook.nb);
220 /* Skip quota reservation fields. */
222 case XFS_TRANS_DQ_BCOUNT:
223 case XFS_TRANS_DQ_DELBCOUNT:
224 case XFS_TRANS_DQ_ICOUNT:
225 case XFS_TRANS_DQ_RTBCOUNT:
226 case XFS_TRANS_DQ_DELRTBCOUNT:
232 /* Ignore dqtrx updates for quota types we don't care about. */
234 case XFS_DQTYPE_USER:
238 case XFS_DQTYPE_GROUP:
242 case XFS_DQTYPE_PROJ:
250 /* Skip inodes that haven't been scanned yet. */
251 if (!xchk_iscan_want_live_update(&xqc->iscan, p->ino))
254 /* Make a shadow quota accounting tracker for this transaction. */
255 mutex_lock(&xqc->lock);
256 dqa = rhashtable_lookup_fast(&xqc->shadow_dquot_acct, &p->tx_id,
257 xqcheck_dqacct_hash_params);
259 dqa = kzalloc(sizeof(struct xqcheck_dqacct), XCHK_GFP_FLAGS);
263 dqa->tx_id = p->tx_id;
264 error = rhashtable_insert_fast(&xqc->shadow_dquot_acct,
265 &dqa->hash, xqcheck_dqacct_hash_params);
270 /* Find the shadow dqtrx (or an empty slot) here. */
271 dqtrx = xqcheck_get_dqtrx(dqa, p->q_type, p->q_id);
274 if (dqtrx->q_type == 0) {
275 dqtrx->q_type = p->q_type;
276 dqtrx->q_id = p->q_id;
282 case XFS_TRANS_DQ_BCOUNT:
283 dqtrx->bcount_delta += p->delta;
285 case XFS_TRANS_DQ_DELBCOUNT:
286 dqtrx->delbcnt_delta += p->delta;
288 case XFS_TRANS_DQ_ICOUNT:
289 dqtrx->icount_delta += p->delta;
291 case XFS_TRANS_DQ_RTBCOUNT:
292 dqtrx->rtbcount_delta += p->delta;
294 case XFS_TRANS_DQ_DELRTBCOUNT:
295 dqtrx->delrtb_delta += p->delta;
299 mutex_unlock(&xqc->lock);
303 xchk_iscan_abort(&xqc->iscan);
304 mutex_unlock(&xqc->lock);
309 * Apply the transaction quota deltas to our shadow quota accounting info when
310 * the regular quota code are doing the same.
313 xqcheck_apply_live_dqtrx(
314 struct notifier_block *nb,
315 unsigned long action,
318 struct xfs_apply_dqtrx_params *p = data;
320 struct xqcheck_dqacct *dqa;
321 struct xqcheck_dqtrx *dqtrx;
322 struct xfarray *counts;
325 xqc = container_of(nb, struct xqcheck, qhook.apply_hook.nb);
327 /* Map the dquot type to an incore counter object. */
329 case XFS_DQTYPE_USER:
330 counts = xqc->ucounts;
332 case XFS_DQTYPE_GROUP:
333 counts = xqc->gcounts;
335 case XFS_DQTYPE_PROJ:
336 counts = xqc->pcounts;
342 if (xchk_iscan_aborted(&xqc->iscan) || counts == NULL)
346 * Find the shadow dqtrx for this transaction and dquot, if any deltas
347 * need to be applied here. If not, we're finished early.
349 mutex_lock(&xqc->lock);
350 dqa = rhashtable_lookup_fast(&xqc->shadow_dquot_acct, &p->tx_id,
351 xqcheck_dqacct_hash_params);
354 dqtrx = xqcheck_get_dqtrx(dqa, p->q_type, p->q_id);
355 if (!dqtrx || dqtrx->q_type == 0)
358 /* Update our shadow dquot if we're committing. */
359 if (action == XFS_APPLY_DQTRX_COMMIT) {
360 error = xqcheck_update_incore_counts(xqc, counts, p->q_id,
362 dqtrx->bcount_delta + dqtrx->delbcnt_delta,
363 dqtrx->rtbcount_delta + dqtrx->delrtb_delta);
368 /* Free the shadow accounting structure if that was the last user. */
370 if (dqa->refcount == 0) {
371 error = rhashtable_remove_fast(&xqc->shadow_dquot_acct,
372 &dqa->hash, xqcheck_dqacct_hash_params);
375 xqcheck_dqacct_free(dqa, NULL);
378 mutex_unlock(&xqc->lock);
382 xchk_iscan_abort(&xqc->iscan);
384 mutex_unlock(&xqc->lock);
388 /* Record this inode's quota usage in our shadow quota counter data. */
390 xqcheck_collect_inode(
392 struct xfs_inode *ip)
394 struct xfs_trans *tp = xqc->sc->tp;
395 xfs_filblks_t nblks, rtblks;
396 uint ilock_flags = 0;
398 bool isreg = S_ISREG(VFS_I(ip)->i_mode);
401 if (xfs_is_quota_inode(&tp->t_mountp->m_sb, ip->i_ino)) {
403 * Quota files are never counted towards quota, so we do not
404 * need to take the lock.
406 xchk_iscan_mark_visited(&xqc->iscan, ip);
410 /* Figure out the data / rt device block counts. */
411 xfs_ilock(ip, XFS_IOLOCK_SHARED);
413 xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
414 if (XFS_IS_REALTIME_INODE(ip)) {
416 * Read in the data fork for rt files so that _count_blocks
417 * can count the number of blocks allocated from the rt volume.
418 * Inodes do not track that separately.
420 ilock_flags = xfs_ilock_data_map_shared(ip);
421 error = xfs_iread_extents(tp, ip, XFS_DATA_FORK);
425 ilock_flags = XFS_ILOCK_SHARED;
426 xfs_ilock(ip, XFS_ILOCK_SHARED);
428 xfs_inode_count_blocks(tp, ip, &nblks, &rtblks);
430 if (xchk_iscan_aborted(&xqc->iscan)) {
435 /* Update the shadow dquot counters. */
436 mutex_lock(&xqc->lock);
438 id = xfs_qm_id_for_quotatype(ip, XFS_DQTYPE_USER);
439 error = xqcheck_update_incore_counts(xqc, xqc->ucounts, id, 1,
446 id = xfs_qm_id_for_quotatype(ip, XFS_DQTYPE_GROUP);
447 error = xqcheck_update_incore_counts(xqc, xqc->gcounts, id, 1,
454 id = xfs_qm_id_for_quotatype(ip, XFS_DQTYPE_PROJ);
455 error = xqcheck_update_incore_counts(xqc, xqc->pcounts, id, 1,
460 mutex_unlock(&xqc->lock);
462 xchk_iscan_mark_visited(&xqc->iscan, ip);
466 mutex_unlock(&xqc->lock);
468 xchk_iscan_abort(&xqc->iscan);
470 xchk_set_incomplete(xqc->sc);
472 xfs_iunlock(ip, ilock_flags);
474 xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
475 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
479 /* Walk all the allocated inodes and run a quota scan on them. */
481 xqcheck_collect_counts(
484 struct xfs_scrub *sc = xqc->sc;
485 struct xfs_inode *ip;
489 * Set up for a potentially lengthy filesystem scan by reducing our
490 * transaction resource usage for the duration. Specifically:
492 * Cancel the transaction to release the log grant space while we scan
495 * Create a new empty transaction to eliminate the possibility of the
496 * inode scan deadlocking on cyclical metadata.
498 * We pass the empty transaction to the file scanning function to avoid
499 * repeatedly cycling empty transactions. This can be done without
500 * risk of deadlock between sb_internal and the IOLOCK (we take the
501 * IOLOCK to quiesce the file before scanning) because empty
502 * transactions do not take sb_internal.
504 xchk_trans_cancel(sc);
505 error = xchk_trans_alloc_empty(sc);
509 while ((error = xchk_iscan_iter(&xqc->iscan, &ip)) == 1) {
510 error = xqcheck_collect_inode(xqc, ip);
515 if (xchk_should_terminate(sc, &error))
518 xchk_iscan_iter_finish(&xqc->iscan);
520 xchk_set_incomplete(sc);
522 * If we couldn't grab an inode that was busy with a state
523 * change, change the error code so that we exit to userspace
524 * as quickly as possible.
532 * Switch out for a real transaction in preparation for building a new
535 xchk_trans_cancel(sc);
536 return xchk_setup_fs(sc);
540 * Part 2: Comparing dquot resource counters. Walk each xfs_dquot, comparing
541 * the resource usage counters against our shadow dquots; and then walk each
542 * shadow dquot (that wasn't covered in the first part), comparing it against
547 * Check the dquot data against what we observed. Caller must hold the dquot
551 xqcheck_compare_dquot(
554 struct xfs_dquot *dq)
556 struct xqcheck_dquot xcdq;
557 struct xfarray *counts = xqcheck_counters_for(xqc, dqtype);
560 if (xchk_iscan_aborted(&xqc->iscan)) {
561 xchk_set_incomplete(xqc->sc);
565 mutex_lock(&xqc->lock);
566 error = xfarray_load_sparse(counts, dq->q_id, &xcdq);
570 if (xcdq.icount != dq->q_ino.count)
571 xchk_qcheck_set_corrupt(xqc->sc, dqtype, dq->q_id);
573 if (xcdq.bcount != dq->q_blk.count)
574 xchk_qcheck_set_corrupt(xqc->sc, dqtype, dq->q_id);
576 if (xcdq.rtbcount != dq->q_rtb.count)
577 xchk_qcheck_set_corrupt(xqc->sc, dqtype, dq->q_id);
579 xcdq.flags |= (XQCHECK_DQUOT_COMPARE_SCANNED | XQCHECK_DQUOT_WRITTEN);
580 error = xfarray_store(counts, dq->q_id, &xcdq);
581 if (error == -EFBIG) {
583 * EFBIG means we tried to store data at too high a byte offset
584 * in the sparse array. IOWs, we cannot complete the check and
585 * must notify userspace that the check was incomplete. This
586 * should never happen outside of the collection phase.
588 xchk_set_incomplete(xqc->sc);
591 mutex_unlock(&xqc->lock);
595 if (xqc->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
601 mutex_unlock(&xqc->lock);
606 * Walk all the observed dquots, and make sure there's a matching incore
607 * dquot and that its counts match ours.
610 xqcheck_walk_observations(
614 struct xqcheck_dquot xcdq;
615 struct xfs_dquot *dq;
616 struct xfarray *counts = xqcheck_counters_for(xqc, dqtype);
617 xfarray_idx_t cur = XFARRAY_CURSOR_INIT;
620 mutex_lock(&xqc->lock);
621 while ((error = xfarray_iter(counts, &cur, &xcdq)) == 1) {
622 xfs_dqid_t id = cur - 1;
624 if (xcdq.flags & XQCHECK_DQUOT_COMPARE_SCANNED)
627 mutex_unlock(&xqc->lock);
629 error = xfs_qm_dqget(xqc->sc->mp, id, dqtype, false, &dq);
630 if (error == -ENOENT) {
631 xchk_qcheck_set_corrupt(xqc->sc, dqtype, id);
637 error = xqcheck_compare_dquot(xqc, dqtype, dq);
642 if (xchk_should_terminate(xqc->sc, &error))
645 mutex_lock(&xqc->lock);
647 mutex_unlock(&xqc->lock);
652 /* Compare the quota counters we observed against the live dquots. */
654 xqcheck_compare_dqtype(
658 struct xchk_dqiter cursor = { };
659 struct xfs_scrub *sc = xqc->sc;
660 struct xfs_dquot *dq;
663 if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
666 /* If the quota CHKD flag is cleared, we need to repair this quota. */
667 if (!(xfs_quota_chkd_flag(dqtype) & sc->mp->m_qflags)) {
668 xchk_qcheck_set_corrupt(xqc->sc, dqtype, 0);
672 /* Compare what we observed against the actual dquots. */
673 xchk_dqiter_init(&cursor, sc, dqtype);
674 while ((error = xchk_dquot_iter(&cursor, &dq)) == 1) {
675 error = xqcheck_compare_dquot(xqc, dqtype, dq);
683 /* Walk all the observed dquots and compare to the incore ones. */
684 return xqcheck_walk_observations(xqc, dqtype);
687 /* Tear down everything associated with a quotacheck. */
689 xqcheck_teardown_scan(
692 struct xqcheck *xqc = priv;
693 struct xfs_quotainfo *qi = xqc->sc->mp->m_quotainfo;
695 /* Discourage any hook functions that might be running. */
696 xchk_iscan_abort(&xqc->iscan);
699 * As noted above, the apply hook is responsible for cleaning up the
700 * shadow dquot accounting data when a transaction completes. The mod
701 * hook must be removed before the apply hook so that we don't
702 * mistakenly leave an active shadow account for the mod hook to get
703 * its hands on. No hooks should be running after these functions
706 xfs_dqtrx_hook_del(qi, &xqc->qhook);
708 if (xqc->shadow_dquot_acct.key_len) {
709 rhashtable_free_and_destroy(&xqc->shadow_dquot_acct,
710 xqcheck_dqacct_free, NULL);
711 xqc->shadow_dquot_acct.key_len = 0;
715 xfarray_destroy(xqc->pcounts);
720 xfarray_destroy(xqc->gcounts);
725 xfarray_destroy(xqc->ucounts);
729 xchk_iscan_teardown(&xqc->iscan);
730 mutex_destroy(&xqc->lock);
735 * Scan all inodes in the entire filesystem to generate quota counter data.
736 * If the scan is successful, the quota data will be left alive for a repair.
737 * If any error occurs, we'll tear everything down.
741 struct xfs_scrub *sc,
745 struct xfs_quotainfo *qi = sc->mp->m_quotainfo;
746 unsigned long long max_dquots = XFS_DQ_ID_MAX + 1ULL;
749 ASSERT(xqc->sc == NULL);
752 mutex_init(&xqc->lock);
754 /* Retry iget every tenth of a second for up to 30 seconds. */
755 xchk_iscan_start(sc, 30000, 100, &xqc->iscan);
758 if (xfs_this_quota_on(sc->mp, XFS_DQTYPE_USER)) {
759 descr = xchk_xfile_descr(sc, "user dquot records");
760 error = xfarray_create(descr, max_dquots,
761 sizeof(struct xqcheck_dquot), &xqc->ucounts);
767 if (xfs_this_quota_on(sc->mp, XFS_DQTYPE_GROUP)) {
768 descr = xchk_xfile_descr(sc, "group dquot records");
769 error = xfarray_create(descr, max_dquots,
770 sizeof(struct xqcheck_dquot), &xqc->gcounts);
776 if (xfs_this_quota_on(sc->mp, XFS_DQTYPE_PROJ)) {
777 descr = xchk_xfile_descr(sc, "project dquot records");
778 error = xfarray_create(descr, max_dquots,
779 sizeof(struct xqcheck_dquot), &xqc->pcounts);
786 * Set up hash table to map transactions to our internal shadow dqtrx
789 error = rhashtable_init(&xqc->shadow_dquot_acct,
790 &xqcheck_dqacct_hash_params);
795 * Hook into the quota code. The hook only triggers for inodes that
796 * were already scanned, and the scanner thread takes each inode's
797 * ILOCK, which means that any in-progress inode updates will finish
798 * before we can scan the inode.
800 * The apply hook (which removes the shadow dquot accounting struct)
801 * must be installed before the mod hook so that we never fail to catch
802 * the end of a quota update sequence and leave stale shadow data.
804 ASSERT(sc->flags & XCHK_FSGATES_QUOTA);
805 xfs_dqtrx_hook_setup(&xqc->qhook, xqcheck_mod_live_ino_dqtrx,
806 xqcheck_apply_live_dqtrx);
808 error = xfs_dqtrx_hook_add(qi, &xqc->qhook);
812 /* Use deferred cleanup to pass the quota count data to repair. */
813 sc->buf_cleanup = xqcheck_teardown_scan;
817 xqcheck_teardown_scan(xqc);
821 /* Scrub all counters for a given quota type. */
824 struct xfs_scrub *sc)
826 struct xqcheck *xqc = sc->buf;
829 /* Check quota counters on the live filesystem. */
830 error = xqcheck_setup_scan(sc, xqc);
834 /* Walk all inodes, picking up quota information. */
835 error = xqcheck_collect_counts(xqc);
836 if (!xchk_xref_process_error(sc, 0, 0, &error))
839 /* Fail fast if we're not playing with a full dataset. */
840 if (xchk_iscan_aborted(&xqc->iscan))
841 xchk_set_incomplete(sc);
842 if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_INCOMPLETE)
845 /* Compare quota counters. */
847 error = xqcheck_compare_dqtype(xqc, XFS_DQTYPE_USER);
848 if (!xchk_xref_process_error(sc, 0, 0, &error))
852 error = xqcheck_compare_dqtype(xqc, XFS_DQTYPE_GROUP);
853 if (!xchk_xref_process_error(sc, 0, 0, &error))
857 error = xqcheck_compare_dqtype(xqc, XFS_DQTYPE_PROJ);
858 if (!xchk_xref_process_error(sc, 0, 0, &error))
862 /* Check one last time for an incomplete dataset. */
863 if (xchk_iscan_aborted(&xqc->iscan))
864 xchk_set_incomplete(sc);