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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2017-2023 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_log_format.h"13#include "xfs_trans.h"14#include "xfs_inode.h"15#include "xfs_quota.h"16#include "xfs_qm.h"17#include "xfs_scrub.h"18#include "xfs_buf_mem.h"19#include "xfs_rmap.h"20#include "xfs_exchrange.h"21#include "xfs_exchmaps.h"22#include "xfs_dir2.h"23#include "xfs_parent.h"24#include "xfs_icache.h"25#include "scrub/scrub.h"26#include "scrub/common.h"27#include "scrub/trace.h"28#include "scrub/repair.h"29#include "scrub/health.h"30#include "scrub/stats.h"31#include "scrub/xfile.h"32#include "scrub/tempfile.h"33#include "scrub/orphanage.h"34 35/*36 * Online Scrub and Repair37 *38 * Traditionally, XFS (the kernel driver) did not know how to check or39 * repair on-disk data structures. That task was left to the xfs_check40 * and xfs_repair tools, both of which require taking the filesystem41 * offline for a thorough but time consuming examination. Online42 * scrub & repair, on the other hand, enables us to check the metadata43 * for obvious errors while carefully stepping around the filesystem's44 * ongoing operations, locking rules, etc.45 *46 * Given that most XFS metadata consist of records stored in a btree,47 * most of the checking functions iterate the btree blocks themselves48 * looking for irregularities. When a record block is encountered, each49 * record can be checked for obviously bad values. Record values can50 * also be cross-referenced against other btrees to look for potential51 * misunderstandings between pieces of metadata.52 *53 * It is expected that the checkers responsible for per-AG metadata54 * structures will lock the AG headers (AGI, AGF, AGFL), iterate the55 * metadata structure, and perform any relevant cross-referencing before56 * unlocking the AG and returning the results to userspace. These57 * scrubbers must not keep an AG locked for too long to avoid tying up58 * the block and inode allocators.59 *60 * Block maps and b-trees rooted in an inode present a special challenge61 * because they can involve extents from any AG. The general scrubber62 * structure of lock -> check -> xref -> unlock still holds, but AG63 * locking order rules /must/ be obeyed to avoid deadlocks. The64 * ordering rule, of course, is that we must lock in increasing AG65 * order. Helper functions are provided to track which AG headers we've66 * already locked. If we detect an imminent locking order violation, we67 * can signal a potential deadlock, in which case the scrubber can jump68 * out to the top level, lock all the AGs in order, and retry the scrub.69 *70 * For file data (directories, extended attributes, symlinks) scrub, we71 * can simply lock the inode and walk the data. For btree data72 * (directories and attributes) we follow the same btree-scrubbing73 * strategy outlined previously to check the records.74 *75 * We use a bit of trickery with transactions to avoid buffer deadlocks76 * if there is a cycle in the metadata. The basic problem is that77 * travelling down a btree involves locking the current buffer at each78 * tree level. If a pointer should somehow point back to a buffer that79 * we've already examined, we will deadlock due to the second buffer80 * locking attempt. Note however that grabbing a buffer in transaction81 * context links the locked buffer to the transaction. If we try to82 * re-grab the buffer in the context of the same transaction, we avoid83 * the second lock attempt and continue. Between the verifier and the84 * scrubber, something will notice that something is amiss and report85 * the corruption. Therefore, each scrubber will allocate an empty86 * transaction, attach buffers to it, and cancel the transaction at the87 * end of the scrub run. Cancelling a non-dirty transaction simply88 * unlocks the buffers.89 *90 * There are four pieces of data that scrub can communicate to91 * userspace. The first is the error code (errno), which can be used to92 * communicate operational errors in performing the scrub. There are93 * also three flags that can be set in the scrub context. If the data94 * structure itself is corrupt, the CORRUPT flag will be set. If95 * the metadata is correct but otherwise suboptimal, the PREEN flag96 * will be set.97 *98 * We perform secondary validation of filesystem metadata by99 * cross-referencing every record with all other available metadata.100 * For example, for block mapping extents, we verify that there are no101 * records in the free space and inode btrees corresponding to that102 * space extent and that there is a corresponding entry in the reverse103 * mapping btree. Inconsistent metadata is noted by setting the104 * XCORRUPT flag; btree query function errors are noted by setting the105 * XFAIL flag and deleting the cursor to prevent further attempts to106 * cross-reference with a defective btree.107 *108 * If a piece of metadata proves corrupt or suboptimal, the userspace109 * program can ask the kernel to apply some tender loving care (TLC) to110 * the metadata object by setting the REPAIR flag and re-calling the111 * scrub ioctl. "Corruption" is defined by metadata violating the112 * on-disk specification; operations cannot continue if the violation is113 * left untreated. It is possible for XFS to continue if an object is114 * "suboptimal", however performance may be degraded. Repairs are115 * usually performed by rebuilding the metadata entirely out of116 * redundant metadata. Optimizing, on the other hand, can sometimes be117 * done without rebuilding entire structures.118 *119 * Generally speaking, the repair code has the following code structure:120 * Lock -> scrub -> repair -> commit -> re-lock -> re-scrub -> unlock.121 * The first check helps us figure out if we need to rebuild or simply122 * optimize the structure so that the rebuild knows what to do. The123 * second check evaluates the completeness of the repair; that is what124 * is reported to userspace.125 *126 * A quick note on symbol prefixes:127 * - "xfs_" are general XFS symbols.128 * - "xchk_" are symbols related to metadata checking.129 * - "xrep_" are symbols related to metadata repair.130 * - "xfs_scrub_" are symbols that tie online fsck to the rest of XFS.131 */132 133/*134 * Scrub probe -- userspace uses this to probe if we're willing to scrub135 * or repair a given mountpoint. This will be used by xfs_scrub to136 * probe the kernel's abilities to scrub (and repair) the metadata. We137 * do this by validating the ioctl inputs from userspace, preparing the138 * filesystem for a scrub (or a repair) operation, and immediately139 * returning to userspace. Userspace can use the returned errno and140 * structure state to decide (in broad terms) if scrub/repair are141 * supported by the running kernel.142 */143static int144xchk_probe(145 struct xfs_scrub *sc)146{147 int error = 0;148 149 if (xchk_should_terminate(sc, &error))150 return error;151 152 return 0;153}154 155/* Scrub setup and teardown */156 157static inline void158xchk_fsgates_disable(159 struct xfs_scrub *sc)160{161 if (!(sc->flags & XCHK_FSGATES_ALL))162 return;163 164 trace_xchk_fsgates_disable(sc, sc->flags & XCHK_FSGATES_ALL);165 166 if (sc->flags & XCHK_FSGATES_DRAIN)167 xfs_drain_wait_disable();168 169 if (sc->flags & XCHK_FSGATES_QUOTA)170 xfs_dqtrx_hook_disable();171 172 if (sc->flags & XCHK_FSGATES_DIRENTS)173 xfs_dir_hook_disable();174 175 if (sc->flags & XCHK_FSGATES_RMAP)176 xfs_rmap_hook_disable();177 178 sc->flags &= ~XCHK_FSGATES_ALL;179}180 181/* Free the resources associated with a scrub subtype. */182void183xchk_scrub_free_subord(184 struct xfs_scrub_subord *sub)185{186 struct xfs_scrub *sc = sub->parent_sc;187 188 ASSERT(sc->ip == sub->sc.ip);189 ASSERT(sc->orphanage == sub->sc.orphanage);190 ASSERT(sc->tempip == sub->sc.tempip);191 192 sc->sm->sm_type = sub->old_smtype;193 sc->sm->sm_flags = sub->old_smflags |194 (sc->sm->sm_flags & XFS_SCRUB_FLAGS_OUT);195 sc->tp = sub->sc.tp;196 197 if (sub->sc.buf) {198 if (sub->sc.buf_cleanup)199 sub->sc.buf_cleanup(sub->sc.buf);200 kvfree(sub->sc.buf);201 }202 if (sub->sc.xmbtp)203 xmbuf_free(sub->sc.xmbtp);204 if (sub->sc.xfile)205 xfile_destroy(sub->sc.xfile);206 207 sc->ilock_flags = sub->sc.ilock_flags;208 sc->orphanage_ilock_flags = sub->sc.orphanage_ilock_flags;209 sc->temp_ilock_flags = sub->sc.temp_ilock_flags;210 211 kfree(sub);212}213 214/* Free all the resources and finish the transactions. */215STATIC int216xchk_teardown(217 struct xfs_scrub *sc,218 int error)219{220 xchk_ag_free(sc, &sc->sa);221 if (sc->tp) {222 if (error == 0 && (sc->sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR))223 error = xfs_trans_commit(sc->tp);224 else225 xfs_trans_cancel(sc->tp);226 sc->tp = NULL;227 }228 if (sc->ip) {229 if (sc->ilock_flags)230 xchk_iunlock(sc, sc->ilock_flags);231 xchk_irele(sc, sc->ip);232 sc->ip = NULL;233 }234 if (sc->flags & XCHK_HAVE_FREEZE_PROT) {235 sc->flags &= ~XCHK_HAVE_FREEZE_PROT;236 mnt_drop_write_file(sc->file);237 }238 if (sc->xmbtp) {239 xmbuf_free(sc->xmbtp);240 sc->xmbtp = NULL;241 }242 if (sc->xfile) {243 xfile_destroy(sc->xfile);244 sc->xfile = NULL;245 }246 if (sc->buf) {247 if (sc->buf_cleanup)248 sc->buf_cleanup(sc->buf);249 kvfree(sc->buf);250 sc->buf_cleanup = NULL;251 sc->buf = NULL;252 }253 254 xrep_tempfile_rele(sc);255 xrep_orphanage_rele(sc);256 xchk_fsgates_disable(sc);257 return error;258}259 260/* Scrubbing dispatch. */261 262static const struct xchk_meta_ops meta_scrub_ops[] = {263 [XFS_SCRUB_TYPE_PROBE] = { /* ioctl presence test */264 .type = ST_NONE,265 .setup = xchk_setup_fs,266 .scrub = xchk_probe,267 .repair = xrep_probe,268 },269 [XFS_SCRUB_TYPE_SB] = { /* superblock */270 .type = ST_PERAG,271 .setup = xchk_setup_agheader,272 .scrub = xchk_superblock,273 .repair = xrep_superblock,274 },275 [XFS_SCRUB_TYPE_AGF] = { /* agf */276 .type = ST_PERAG,277 .setup = xchk_setup_agheader,278 .scrub = xchk_agf,279 .repair = xrep_agf,280 },281 [XFS_SCRUB_TYPE_AGFL]= { /* agfl */282 .type = ST_PERAG,283 .setup = xchk_setup_agheader,284 .scrub = xchk_agfl,285 .repair = xrep_agfl,286 },287 [XFS_SCRUB_TYPE_AGI] = { /* agi */288 .type = ST_PERAG,289 .setup = xchk_setup_agheader,290 .scrub = xchk_agi,291 .repair = xrep_agi,292 },293 [XFS_SCRUB_TYPE_BNOBT] = { /* bnobt */294 .type = ST_PERAG,295 .setup = xchk_setup_ag_allocbt,296 .scrub = xchk_allocbt,297 .repair = xrep_allocbt,298 .repair_eval = xrep_revalidate_allocbt,299 },300 [XFS_SCRUB_TYPE_CNTBT] = { /* cntbt */301 .type = ST_PERAG,302 .setup = xchk_setup_ag_allocbt,303 .scrub = xchk_allocbt,304 .repair = xrep_allocbt,305 .repair_eval = xrep_revalidate_allocbt,306 },307 [XFS_SCRUB_TYPE_INOBT] = { /* inobt */308 .type = ST_PERAG,309 .setup = xchk_setup_ag_iallocbt,310 .scrub = xchk_iallocbt,311 .repair = xrep_iallocbt,312 .repair_eval = xrep_revalidate_iallocbt,313 },314 [XFS_SCRUB_TYPE_FINOBT] = { /* finobt */315 .type = ST_PERAG,316 .setup = xchk_setup_ag_iallocbt,317 .scrub = xchk_iallocbt,318 .has = xfs_has_finobt,319 .repair = xrep_iallocbt,320 .repair_eval = xrep_revalidate_iallocbt,321 },322 [XFS_SCRUB_TYPE_RMAPBT] = { /* rmapbt */323 .type = ST_PERAG,324 .setup = xchk_setup_ag_rmapbt,325 .scrub = xchk_rmapbt,326 .has = xfs_has_rmapbt,327 .repair = xrep_rmapbt,328 },329 [XFS_SCRUB_TYPE_REFCNTBT] = { /* refcountbt */330 .type = ST_PERAG,331 .setup = xchk_setup_ag_refcountbt,332 .scrub = xchk_refcountbt,333 .has = xfs_has_reflink,334 .repair = xrep_refcountbt,335 },336 [XFS_SCRUB_TYPE_INODE] = { /* inode record */337 .type = ST_INODE,338 .setup = xchk_setup_inode,339 .scrub = xchk_inode,340 .repair = xrep_inode,341 },342 [XFS_SCRUB_TYPE_BMBTD] = { /* inode data fork */343 .type = ST_INODE,344 .setup = xchk_setup_inode_bmap,345 .scrub = xchk_bmap_data,346 .repair = xrep_bmap_data,347 },348 [XFS_SCRUB_TYPE_BMBTA] = { /* inode attr fork */349 .type = ST_INODE,350 .setup = xchk_setup_inode_bmap,351 .scrub = xchk_bmap_attr,352 .repair = xrep_bmap_attr,353 },354 [XFS_SCRUB_TYPE_BMBTC] = { /* inode CoW fork */355 .type = ST_INODE,356 .setup = xchk_setup_inode_bmap,357 .scrub = xchk_bmap_cow,358 .repair = xrep_bmap_cow,359 },360 [XFS_SCRUB_TYPE_DIR] = { /* directory */361 .type = ST_INODE,362 .setup = xchk_setup_directory,363 .scrub = xchk_directory,364 .repair = xrep_directory,365 },366 [XFS_SCRUB_TYPE_XATTR] = { /* extended attributes */367 .type = ST_INODE,368 .setup = xchk_setup_xattr,369 .scrub = xchk_xattr,370 .repair = xrep_xattr,371 },372 [XFS_SCRUB_TYPE_SYMLINK] = { /* symbolic link */373 .type = ST_INODE,374 .setup = xchk_setup_symlink,375 .scrub = xchk_symlink,376 .repair = xrep_symlink,377 },378 [XFS_SCRUB_TYPE_PARENT] = { /* parent pointers */379 .type = ST_INODE,380 .setup = xchk_setup_parent,381 .scrub = xchk_parent,382 .repair = xrep_parent,383 },384 [XFS_SCRUB_TYPE_RTBITMAP] = { /* realtime bitmap */385 .type = ST_FS,386 .setup = xchk_setup_rtbitmap,387 .scrub = xchk_rtbitmap,388 .repair = xrep_rtbitmap,389 },390 [XFS_SCRUB_TYPE_RTSUM] = { /* realtime summary */391 .type = ST_FS,392 .setup = xchk_setup_rtsummary,393 .scrub = xchk_rtsummary,394 .repair = xrep_rtsummary,395 },396 [XFS_SCRUB_TYPE_UQUOTA] = { /* user quota */397 .type = ST_FS,398 .setup = xchk_setup_quota,399 .scrub = xchk_quota,400 .repair = xrep_quota,401 },402 [XFS_SCRUB_TYPE_GQUOTA] = { /* group quota */403 .type = ST_FS,404 .setup = xchk_setup_quota,405 .scrub = xchk_quota,406 .repair = xrep_quota,407 },408 [XFS_SCRUB_TYPE_PQUOTA] = { /* project quota */409 .type = ST_FS,410 .setup = xchk_setup_quota,411 .scrub = xchk_quota,412 .repair = xrep_quota,413 },414 [XFS_SCRUB_TYPE_FSCOUNTERS] = { /* fs summary counters */415 .type = ST_FS,416 .setup = xchk_setup_fscounters,417 .scrub = xchk_fscounters,418 .repair = xrep_fscounters,419 },420 [XFS_SCRUB_TYPE_QUOTACHECK] = { /* quota counters */421 .type = ST_FS,422 .setup = xchk_setup_quotacheck,423 .scrub = xchk_quotacheck,424 .repair = xrep_quotacheck,425 },426 [XFS_SCRUB_TYPE_NLINKS] = { /* inode link counts */427 .type = ST_FS,428 .setup = xchk_setup_nlinks,429 .scrub = xchk_nlinks,430 .repair = xrep_nlinks,431 },432 [XFS_SCRUB_TYPE_HEALTHY] = { /* fs healthy; clean all reminders */433 .type = ST_FS,434 .setup = xchk_setup_fs,435 .scrub = xchk_health_record,436 .repair = xrep_notsupported,437 },438 [XFS_SCRUB_TYPE_DIRTREE] = { /* directory tree structure */439 .type = ST_INODE,440 .setup = xchk_setup_dirtree,441 .scrub = xchk_dirtree,442 .has = xfs_has_parent,443 .repair = xrep_dirtree,444 },445};446 447static int448xchk_validate_inputs(449 struct xfs_mount *mp,450 struct xfs_scrub_metadata *sm)451{452 int error;453 const struct xchk_meta_ops *ops;454 455 error = -EINVAL;456 /* Check our inputs. */457 sm->sm_flags &= ~XFS_SCRUB_FLAGS_OUT;458 if (sm->sm_flags & ~XFS_SCRUB_FLAGS_IN)459 goto out;460 /* sm_reserved[] must be zero */461 if (memchr_inv(sm->sm_reserved, 0, sizeof(sm->sm_reserved)))462 goto out;463 464 error = -ENOENT;465 /* Do we know about this type of metadata? */466 if (sm->sm_type >= XFS_SCRUB_TYPE_NR)467 goto out;468 ops = &meta_scrub_ops[sm->sm_type];469 if (ops->setup == NULL || ops->scrub == NULL)470 goto out;471 /* Does this fs even support this type of metadata? */472 if (ops->has && !ops->has(mp))473 goto out;474 475 error = -EINVAL;476 /* restricting fields must be appropriate for type */477 switch (ops->type) {478 case ST_NONE:479 case ST_FS:480 if (sm->sm_ino || sm->sm_gen || sm->sm_agno)481 goto out;482 break;483 case ST_PERAG:484 if (sm->sm_ino || sm->sm_gen ||485 sm->sm_agno >= mp->m_sb.sb_agcount)486 goto out;487 break;488 case ST_INODE:489 if (sm->sm_agno || (sm->sm_gen && !sm->sm_ino))490 goto out;491 break;492 default:493 goto out;494 }495 496 /* No rebuild without repair. */497 if ((sm->sm_flags & XFS_SCRUB_IFLAG_FORCE_REBUILD) &&498 !(sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR))499 return -EINVAL;500 501 /*502 * We only want to repair read-write v5+ filesystems. Defer the check503 * for ops->repair until after our scrub confirms that we need to504 * perform repairs so that we avoid failing due to not supporting505 * repairing an object that doesn't need repairs.506 */507 if (sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR) {508 error = -EOPNOTSUPP;509 if (!xfs_has_crc(mp))510 goto out;511 512 error = -EROFS;513 if (xfs_is_readonly(mp))514 goto out;515 }516 517 error = 0;518out:519 return error;520}521 522#ifdef CONFIG_XFS_ONLINE_REPAIR523static inline void xchk_postmortem(struct xfs_scrub *sc)524{525 /*526 * Userspace asked us to repair something, we repaired it, rescanned527 * it, and the rescan says it's still broken. Scream about this in528 * the system logs.529 */530 if ((sc->sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR) &&531 (sc->sm->sm_flags & (XFS_SCRUB_OFLAG_CORRUPT |532 XFS_SCRUB_OFLAG_XCORRUPT)))533 xrep_failure(sc->mp);534}535#else536static inline void xchk_postmortem(struct xfs_scrub *sc)537{538 /*539 * Userspace asked us to scrub something, it's broken, and we have no540 * way of fixing it. Scream in the logs.541 */542 if (sc->sm->sm_flags & (XFS_SCRUB_OFLAG_CORRUPT |543 XFS_SCRUB_OFLAG_XCORRUPT))544 xfs_alert_ratelimited(sc->mp,545 "Corruption detected during scrub.");546}547#endif /* CONFIG_XFS_ONLINE_REPAIR */548 549/*550 * Create a new scrub context from an existing one, but with a different scrub551 * type.552 */553struct xfs_scrub_subord *554xchk_scrub_create_subord(555 struct xfs_scrub *sc,556 unsigned int subtype)557{558 struct xfs_scrub_subord *sub;559 560 sub = kzalloc(sizeof(*sub), XCHK_GFP_FLAGS);561 if (!sub)562 return ERR_PTR(-ENOMEM);563 564 sub->old_smtype = sc->sm->sm_type;565 sub->old_smflags = sc->sm->sm_flags;566 sub->parent_sc = sc;567 memcpy(&sub->sc, sc, sizeof(struct xfs_scrub));568 sub->sc.ops = &meta_scrub_ops[subtype];569 sub->sc.sm->sm_type = subtype;570 sub->sc.sm->sm_flags &= ~XFS_SCRUB_FLAGS_OUT;571 sub->sc.buf = NULL;572 sub->sc.buf_cleanup = NULL;573 sub->sc.xfile = NULL;574 sub->sc.xmbtp = NULL;575 576 return sub;577}578 579/* Dispatch metadata scrubbing. */580STATIC int581xfs_scrub_metadata(582 struct file *file,583 struct xfs_scrub_metadata *sm)584{585 struct xchk_stats_run run = { };586 struct xfs_scrub *sc;587 struct xfs_mount *mp = XFS_I(file_inode(file))->i_mount;588 u64 check_start;589 int error = 0;590 591 BUILD_BUG_ON(sizeof(meta_scrub_ops) !=592 (sizeof(struct xchk_meta_ops) * XFS_SCRUB_TYPE_NR));593 594 trace_xchk_start(XFS_I(file_inode(file)), sm, error);595 596 /* Forbidden if we are shut down or mounted norecovery. */597 error = -ESHUTDOWN;598 if (xfs_is_shutdown(mp))599 goto out;600 error = -ENOTRECOVERABLE;601 if (xfs_has_norecovery(mp))602 goto out;603 604 error = xchk_validate_inputs(mp, sm);605 if (error)606 goto out;607 608 xfs_warn_mount(mp, XFS_OPSTATE_WARNED_SCRUB,609 "EXPERIMENTAL online scrub feature in use. Use at your own risk!");610 611 sc = kzalloc(sizeof(struct xfs_scrub), XCHK_GFP_FLAGS);612 if (!sc) {613 error = -ENOMEM;614 goto out;615 }616 617 sc->mp = mp;618 sc->file = file;619 sc->sm = sm;620 sc->ops = &meta_scrub_ops[sm->sm_type];621 sc->sick_mask = xchk_health_mask_for_scrub_type(sm->sm_type);622 sc->relax = INIT_XCHK_RELAX;623retry_op:624 /*625 * When repairs are allowed, prevent freezing or readonly remount while626 * scrub is running with a real transaction.627 */628 if (sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR) {629 error = mnt_want_write_file(sc->file);630 if (error)631 goto out_sc;632 633 sc->flags |= XCHK_HAVE_FREEZE_PROT;634 }635 636 /* Set up for the operation. */637 error = sc->ops->setup(sc);638 if (error == -EDEADLOCK && !(sc->flags & XCHK_TRY_HARDER))639 goto try_harder;640 if (error == -ECHRNG && !(sc->flags & XCHK_NEED_DRAIN))641 goto need_drain;642 if (error)643 goto out_teardown;644 645 /* Scrub for errors. */646 check_start = xchk_stats_now();647 if ((sc->flags & XREP_ALREADY_FIXED) && sc->ops->repair_eval != NULL)648 error = sc->ops->repair_eval(sc);649 else650 error = sc->ops->scrub(sc);651 run.scrub_ns += xchk_stats_elapsed_ns(check_start);652 if (error == -EDEADLOCK && !(sc->flags & XCHK_TRY_HARDER))653 goto try_harder;654 if (error == -ECHRNG && !(sc->flags & XCHK_NEED_DRAIN))655 goto need_drain;656 if (error || (sm->sm_flags & XFS_SCRUB_OFLAG_INCOMPLETE))657 goto out_teardown;658 659 xchk_update_health(sc);660 661 if (xchk_could_repair(sc)) {662 /*663 * If userspace asked for a repair but it wasn't necessary,664 * report that back to userspace.665 */666 if (!xrep_will_attempt(sc)) {667 sc->sm->sm_flags |= XFS_SCRUB_OFLAG_NO_REPAIR_NEEDED;668 goto out_nofix;669 }670 671 /*672 * If it's broken, userspace wants us to fix it, and we haven't673 * already tried to fix it, then attempt a repair.674 */675 error = xrep_attempt(sc, &run);676 if (error == -EAGAIN) {677 /*678 * Either the repair function succeeded or it couldn't679 * get all the resources it needs; either way, we go680 * back to the beginning and call the scrub function.681 */682 error = xchk_teardown(sc, 0);683 if (error) {684 xrep_failure(mp);685 goto out_sc;686 }687 goto retry_op;688 }689 }690 691out_nofix:692 xchk_postmortem(sc);693out_teardown:694 error = xchk_teardown(sc, error);695out_sc:696 if (error != -ENOENT)697 xchk_stats_merge(mp, sm, &run);698 kfree(sc);699out:700 trace_xchk_done(XFS_I(file_inode(file)), sm, error);701 if (error == -EFSCORRUPTED || error == -EFSBADCRC) {702 sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;703 error = 0;704 }705 return error;706need_drain:707 error = xchk_teardown(sc, 0);708 if (error)709 goto out_sc;710 sc->flags |= XCHK_NEED_DRAIN;711 run.retries++;712 goto retry_op;713try_harder:714 /*715 * Scrubbers return -EDEADLOCK to mean 'try harder'. Tear down716 * everything we hold, then set up again with preparation for717 * worst-case scenarios.718 */719 error = xchk_teardown(sc, 0);720 if (error)721 goto out_sc;722 sc->flags |= XCHK_TRY_HARDER;723 run.retries++;724 goto retry_op;725}726 727/* Scrub one aspect of one piece of metadata. */728int729xfs_ioc_scrub_metadata(730 struct file *file,731 void __user *arg)732{733 struct xfs_scrub_metadata scrub;734 int error;735 736 if (!capable(CAP_SYS_ADMIN))737 return -EPERM;738 739 if (copy_from_user(&scrub, arg, sizeof(scrub)))740 return -EFAULT;741 742 error = xfs_scrub_metadata(file, &scrub);743 if (error)744 return error;745 746 if (copy_to_user(arg, &scrub, sizeof(scrub)))747 return -EFAULT;748 749 return 0;750}751 752/* Decide if there have been any scrub failures up to this point. */753static inline int754xfs_scrubv_check_barrier(755 struct xfs_mount *mp,756 const struct xfs_scrub_vec *vectors,757 const struct xfs_scrub_vec *stop_vec)758{759 const struct xfs_scrub_vec *v;760 __u32 failmask;761 762 failmask = stop_vec->sv_flags & XFS_SCRUB_FLAGS_OUT;763 764 for (v = vectors; v < stop_vec; v++) {765 if (v->sv_type == XFS_SCRUB_TYPE_BARRIER)766 continue;767 768 /*769 * Runtime errors count as a previous failure, except the ones770 * used to ask userspace to retry.771 */772 switch (v->sv_ret) {773 case -EBUSY:774 case -ENOENT:775 case -EUSERS:776 case 0:777 break;778 default:779 return -ECANCELED;780 }781 782 /*783 * If any of the out-flags on the scrub vector match the mask784 * that was set on the barrier vector, that's a previous fail.785 */786 if (v->sv_flags & failmask)787 return -ECANCELED;788 }789 790 return 0;791}792 793/*794 * If the caller provided us with a nonzero inode number that isn't the ioctl795 * file, try to grab a reference to it to eliminate all further untrusted inode796 * lookups. If we can't get the inode, let each scrub function try again.797 */798STATIC struct xfs_inode *799xchk_scrubv_open_by_handle(800 struct xfs_mount *mp,801 const struct xfs_scrub_vec_head *head)802{803 struct xfs_trans *tp;804 struct xfs_inode *ip;805 int error;806 807 error = xfs_trans_alloc_empty(mp, &tp);808 if (error)809 return NULL;810 811 error = xfs_iget(mp, tp, head->svh_ino, XCHK_IGET_FLAGS, 0, &ip);812 xfs_trans_cancel(tp);813 if (error)814 return NULL;815 816 if (VFS_I(ip)->i_generation != head->svh_gen) {817 xfs_irele(ip);818 return NULL;819 }820 821 return ip;822}823 824/* Vectored scrub implementation to reduce ioctl calls. */825int826xfs_ioc_scrubv_metadata(827 struct file *file,828 void __user *arg)829{830 struct xfs_scrub_vec_head head;831 struct xfs_scrub_vec_head __user *uhead = arg;832 struct xfs_scrub_vec *vectors;833 struct xfs_scrub_vec __user *uvectors;834 struct xfs_inode *ip_in = XFS_I(file_inode(file));835 struct xfs_mount *mp = ip_in->i_mount;836 struct xfs_inode *handle_ip = NULL;837 struct xfs_scrub_vec *v;838 size_t vec_bytes;839 unsigned int i;840 int error = 0;841 842 if (!capable(CAP_SYS_ADMIN))843 return -EPERM;844 845 if (copy_from_user(&head, uhead, sizeof(head)))846 return -EFAULT;847 848 if (head.svh_reserved)849 return -EINVAL;850 if (head.svh_flags & ~XFS_SCRUB_VEC_FLAGS_ALL)851 return -EINVAL;852 if (head.svh_nr == 0)853 return 0;854 855 vec_bytes = array_size(head.svh_nr, sizeof(struct xfs_scrub_vec));856 if (vec_bytes > PAGE_SIZE)857 return -ENOMEM;858 859 uvectors = u64_to_user_ptr(head.svh_vectors);860 vectors = memdup_user(uvectors, vec_bytes);861 if (IS_ERR(vectors))862 return PTR_ERR(vectors);863 864 trace_xchk_scrubv_start(ip_in, &head);865 866 for (i = 0, v = vectors; i < head.svh_nr; i++, v++) {867 if (v->sv_reserved) {868 error = -EINVAL;869 goto out_free;870 }871 872 if (v->sv_type == XFS_SCRUB_TYPE_BARRIER &&873 (v->sv_flags & ~XFS_SCRUB_FLAGS_OUT)) {874 error = -EINVAL;875 goto out_free;876 }877 878 trace_xchk_scrubv_item(mp, &head, i, v);879 }880 881 /*882 * If the caller wants us to do a scrub-by-handle and the file used to883 * call the ioctl is not the same file, load the incore inode and pin884 * it across all the scrubv actions to avoid repeated UNTRUSTED885 * lookups. The reference is not passed to deeper layers of scrub886 * because each scrubber gets to decide its own strategy and return887 * values for getting an inode.888 */889 if (head.svh_ino && head.svh_ino != ip_in->i_ino)890 handle_ip = xchk_scrubv_open_by_handle(mp, &head);891 892 /* Run all the scrubbers. */893 for (i = 0, v = vectors; i < head.svh_nr; i++, v++) {894 struct xfs_scrub_metadata sm = {895 .sm_type = v->sv_type,896 .sm_flags = v->sv_flags,897 .sm_ino = head.svh_ino,898 .sm_gen = head.svh_gen,899 .sm_agno = head.svh_agno,900 };901 902 if (v->sv_type == XFS_SCRUB_TYPE_BARRIER) {903 v->sv_ret = xfs_scrubv_check_barrier(mp, vectors, v);904 if (v->sv_ret) {905 trace_xchk_scrubv_barrier_fail(mp, &head, i, v);906 break;907 }908 909 continue;910 }911 912 v->sv_ret = xfs_scrub_metadata(file, &sm);913 v->sv_flags = sm.sm_flags;914 915 trace_xchk_scrubv_outcome(mp, &head, i, v);916 917 if (head.svh_rest_us) {918 ktime_t expires;919 920 expires = ktime_add_ns(ktime_get(),921 head.svh_rest_us * 1000);922 set_current_state(TASK_KILLABLE);923 schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);924 }925 926 if (fatal_signal_pending(current)) {927 error = -EINTR;928 goto out_free;929 }930 }931 932 if (copy_to_user(uvectors, vectors, vec_bytes) ||933 copy_to_user(uhead, &head, sizeof(head))) {934 error = -EFAULT;935 goto out_free;936 }937 938out_free:939 if (handle_ip)940 xfs_irele(handle_ip);941 kfree(vectors);942 return error;943}944