linux/fs/gfs2/recovery.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   5 */
   6
   7#include <linux/module.h>
   8#include <linux/slab.h>
   9#include <linux/spinlock.h>
  10#include <linux/completion.h>
  11#include <linux/buffer_head.h>
  12#include <linux/gfs2_ondisk.h>
  13#include <linux/crc32.h>
  14#include <linux/crc32c.h>
  15#include <linux/ktime.h>
  16
  17#include "gfs2.h"
  18#include "incore.h"
  19#include "bmap.h"
  20#include "glock.h"
  21#include "glops.h"
  22#include "log.h"
  23#include "lops.h"
  24#include "meta_io.h"
  25#include "recovery.h"
  26#include "super.h"
  27#include "util.h"
  28#include "dir.h"
  29
  30struct workqueue_struct *gfs_recovery_wq;
  31
  32int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
  33                           struct buffer_head **bh)
  34{
  35        struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
  36        struct gfs2_glock *gl = ip->i_gl;
  37        u64 dblock;
  38        u32 extlen;
  39        int error;
  40
  41        extlen = 32;
  42        error = gfs2_get_extent(&ip->i_inode, blk, &dblock, &extlen);
  43        if (error)
  44                return error;
  45        if (!dblock) {
  46                gfs2_consist_inode(ip);
  47                return -EIO;
  48        }
  49
  50        *bh = gfs2_meta_ra(gl, dblock, extlen);
  51
  52        return error;
  53}
  54
  55int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  56{
  57        struct list_head *head = &jd->jd_revoke_list;
  58        struct gfs2_revoke_replay *rr;
  59        int found = 0;
  60
  61        list_for_each_entry(rr, head, rr_list) {
  62                if (rr->rr_blkno == blkno) {
  63                        found = 1;
  64                        break;
  65                }
  66        }
  67
  68        if (found) {
  69                rr->rr_where = where;
  70                return 0;
  71        }
  72
  73        rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
  74        if (!rr)
  75                return -ENOMEM;
  76
  77        rr->rr_blkno = blkno;
  78        rr->rr_where = where;
  79        list_add(&rr->rr_list, head);
  80
  81        return 1;
  82}
  83
  84int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  85{
  86        struct gfs2_revoke_replay *rr;
  87        int wrap, a, b, revoke;
  88        int found = 0;
  89
  90        list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) {
  91                if (rr->rr_blkno == blkno) {
  92                        found = 1;
  93                        break;
  94                }
  95        }
  96
  97        if (!found)
  98                return 0;
  99
 100        wrap = (rr->rr_where < jd->jd_replay_tail);
 101        a = (jd->jd_replay_tail < where);
 102        b = (where < rr->rr_where);
 103        revoke = (wrap) ? (a || b) : (a && b);
 104
 105        return revoke;
 106}
 107
 108void gfs2_revoke_clean(struct gfs2_jdesc *jd)
 109{
 110        struct list_head *head = &jd->jd_revoke_list;
 111        struct gfs2_revoke_replay *rr;
 112
 113        while (!list_empty(head)) {
 114                rr = list_first_entry(head, struct gfs2_revoke_replay, rr_list);
 115                list_del(&rr->rr_list);
 116                kfree(rr);
 117        }
 118}
 119
 120int __get_log_header(struct gfs2_sbd *sdp, const struct gfs2_log_header *lh,
 121                     unsigned int blkno, struct gfs2_log_header_host *head)
 122{
 123        u32 hash, crc;
 124
 125        if (lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
 126            lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
 127            (blkno && be32_to_cpu(lh->lh_blkno) != blkno))
 128                return 1;
 129
 130        hash = crc32(~0, lh, LH_V1_SIZE - 4);
 131        hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
 132
 133        if (be32_to_cpu(lh->lh_hash) != hash)
 134                return 1;
 135
 136        crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
 137                     sdp->sd_sb.sb_bsize - LH_V1_SIZE - 4);
 138
 139        if ((lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc))
 140                return 1;
 141
 142        head->lh_sequence = be64_to_cpu(lh->lh_sequence);
 143        head->lh_flags = be32_to_cpu(lh->lh_flags);
 144        head->lh_tail = be32_to_cpu(lh->lh_tail);
 145        head->lh_blkno = be32_to_cpu(lh->lh_blkno);
 146
 147        head->lh_local_total = be64_to_cpu(lh->lh_local_total);
 148        head->lh_local_free = be64_to_cpu(lh->lh_local_free);
 149        head->lh_local_dinodes = be64_to_cpu(lh->lh_local_dinodes);
 150
 151        return 0;
 152}
 153/**
 154 * get_log_header - read the log header for a given segment
 155 * @jd: the journal
 156 * @blk: the block to look at
 157 * @head: the log header to return
 158 *
 159 * Read the log header for a given segement in a given journal.  Do a few
 160 * sanity checks on it.
 161 *
 162 * Returns: 0 on success,
 163 *          1 if the header was invalid or incomplete,
 164 *          errno on error
 165 */
 166
 167static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
 168                          struct gfs2_log_header_host *head)
 169{
 170        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 171        struct buffer_head *bh;
 172        int error;
 173
 174        error = gfs2_replay_read_block(jd, blk, &bh);
 175        if (error)
 176                return error;
 177
 178        error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
 179                                 blk, head);
 180        brelse(bh);
 181
 182        return error;
 183}
 184
 185/**
 186 * foreach_descriptor - go through the active part of the log
 187 * @jd: the journal
 188 * @start: the first log header in the active region
 189 * @end: the last log header (don't process the contents of this entry))
 190 * @pass: iteration number (foreach_descriptor() is called in a for() loop)
 191 *
 192 * Call a given function once for every log descriptor in the active
 193 * portion of the log.
 194 *
 195 * Returns: errno
 196 */
 197
 198static int foreach_descriptor(struct gfs2_jdesc *jd, u32 start,
 199                              unsigned int end, int pass)
 200{
 201        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 202        struct buffer_head *bh;
 203        struct gfs2_log_descriptor *ld;
 204        int error = 0;
 205        u32 length;
 206        __be64 *ptr;
 207        unsigned int offset = sizeof(struct gfs2_log_descriptor);
 208        offset += sizeof(__be64) - 1;
 209        offset &= ~(sizeof(__be64) - 1);
 210
 211        while (start != end) {
 212                error = gfs2_replay_read_block(jd, start, &bh);
 213                if (error)
 214                        return error;
 215                if (gfs2_meta_check(sdp, bh)) {
 216                        brelse(bh);
 217                        return -EIO;
 218                }
 219                ld = (struct gfs2_log_descriptor *)bh->b_data;
 220                length = be32_to_cpu(ld->ld_length);
 221
 222                if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
 223                        struct gfs2_log_header_host lh;
 224                        error = get_log_header(jd, start, &lh);
 225                        if (!error) {
 226                                gfs2_replay_incr_blk(jd, &start);
 227                                brelse(bh);
 228                                continue;
 229                        }
 230                        if (error == 1) {
 231                                gfs2_consist_inode(GFS2_I(jd->jd_inode));
 232                                error = -EIO;
 233                        }
 234                        brelse(bh);
 235                        return error;
 236                } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
 237                        brelse(bh);
 238                        return -EIO;
 239                }
 240                ptr = (__be64 *)(bh->b_data + offset);
 241                error = lops_scan_elements(jd, start, ld, ptr, pass);
 242                if (error) {
 243                        brelse(bh);
 244                        return error;
 245                }
 246
 247                while (length--)
 248                        gfs2_replay_incr_blk(jd, &start);
 249
 250                brelse(bh);
 251        }
 252
 253        return 0;
 254}
 255
 256/**
 257 * clean_journal - mark a dirty journal as being clean
 258 * @jd: the journal
 259 * @head: the head journal to start from
 260 *
 261 * Returns: errno
 262 */
 263
 264static void clean_journal(struct gfs2_jdesc *jd,
 265                          struct gfs2_log_header_host *head)
 266{
 267        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 268        u32 lblock = head->lh_blkno;
 269
 270        gfs2_replay_incr_blk(jd, &lblock);
 271        gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, lblock,
 272                              GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
 273                              REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
 274        if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
 275                sdp->sd_log_flush_head = lblock;
 276                gfs2_log_incr_head(sdp);
 277        }
 278}
 279
 280
 281static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 282                               unsigned int message)
 283{
 284        char env_jid[20];
 285        char env_status[20];
 286        char *envp[] = { env_jid, env_status, NULL };
 287        struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 288
 289        ls->ls_recover_jid_done = jid;
 290        ls->ls_recover_jid_status = message;
 291        sprintf(env_jid, "JID=%u", jid);
 292        sprintf(env_status, "RECOVERY=%s",
 293                message == LM_RD_SUCCESS ? "Done" : "Failed");
 294        kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 295
 296        if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
 297                sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 298}
 299
 300/**
 301 * update_statfs_inode - Update the master statfs inode or zero out the local
 302 *                       statfs inode for a given journal.
 303 * @jd: The journal
 304 * @head: If NULL, @inode is the local statfs inode and we need to zero it out.
 305 *        Otherwise, it @head contains the statfs change info that needs to be
 306 *        synced to the master statfs inode (pointed to by @inode).
 307 * @inode: statfs inode to update.
 308 */
 309static int update_statfs_inode(struct gfs2_jdesc *jd,
 310                               struct gfs2_log_header_host *head,
 311                               struct inode *inode)
 312{
 313        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 314        struct gfs2_inode *ip;
 315        struct buffer_head *bh;
 316        struct gfs2_statfs_change_host sc;
 317        int error = 0;
 318
 319        BUG_ON(!inode);
 320        ip = GFS2_I(inode);
 321
 322        error = gfs2_meta_inode_buffer(ip, &bh);
 323        if (error)
 324                goto out;
 325
 326        spin_lock(&sdp->sd_statfs_spin);
 327
 328        if (head) { /* Update the master statfs inode */
 329                gfs2_statfs_change_in(&sc, bh->b_data + sizeof(struct gfs2_dinode));
 330                sc.sc_total += head->lh_local_total;
 331                sc.sc_free += head->lh_local_free;
 332                sc.sc_dinodes += head->lh_local_dinodes;
 333                gfs2_statfs_change_out(&sc, bh->b_data + sizeof(struct gfs2_dinode));
 334
 335                fs_info(sdp, "jid=%u: Updated master statfs Total:%lld, "
 336                        "Free:%lld, Dinodes:%lld after change "
 337                        "[%+lld,%+lld,%+lld]\n", jd->jd_jid, sc.sc_total,
 338                        sc.sc_free, sc.sc_dinodes, head->lh_local_total,
 339                        head->lh_local_free, head->lh_local_dinodes);
 340        } else { /* Zero out the local statfs inode */
 341                memset(bh->b_data + sizeof(struct gfs2_dinode), 0,
 342                       sizeof(struct gfs2_statfs_change));
 343                /* If it's our own journal, reset any in-memory changes too */
 344                if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
 345                        memset(&sdp->sd_statfs_local, 0,
 346                               sizeof(struct gfs2_statfs_change_host));
 347                }
 348        }
 349        spin_unlock(&sdp->sd_statfs_spin);
 350
 351        mark_buffer_dirty(bh);
 352        brelse(bh);
 353        gfs2_inode_metasync(ip->i_gl);
 354
 355out:
 356        return error;
 357}
 358
 359/**
 360 * recover_local_statfs - Update the master and local statfs changes for this
 361 *                        journal.
 362 *
 363 * Previously, statfs updates would be read in from the local statfs inode and
 364 * synced to the master statfs inode during recovery.
 365 *
 366 * We now use the statfs updates in the journal head to update the master statfs
 367 * inode instead of reading in from the local statfs inode. To preserve backward
 368 * compatibility with kernels that can't do this, we still need to keep the
 369 * local statfs inode up to date by writing changes to it. At some point in the
 370 * future, we can do away with the local statfs inodes altogether and keep the
 371 * statfs changes solely in the journal.
 372 *
 373 * @jd: the journal
 374 * @head: the journal head
 375 *
 376 * Returns: errno
 377 */
 378static void recover_local_statfs(struct gfs2_jdesc *jd,
 379                                 struct gfs2_log_header_host *head)
 380{
 381        int error;
 382        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 383
 384        if (!head->lh_local_total && !head->lh_local_free
 385            && !head->lh_local_dinodes) /* No change */
 386                goto zero_local;
 387
 388         /* First update the master statfs inode with the changes we
 389          * found in the journal. */
 390        error = update_statfs_inode(jd, head, sdp->sd_statfs_inode);
 391        if (error)
 392                goto out;
 393
 394zero_local:
 395        /* Zero out the local statfs inode so any changes in there
 396         * are not re-recovered. */
 397        error = update_statfs_inode(jd, NULL,
 398                                    find_local_statfs_inode(sdp, jd->jd_jid));
 399out:
 400        return;
 401}
 402
 403void gfs2_recover_func(struct work_struct *work)
 404{
 405        struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
 406        struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 407        struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 408        struct gfs2_log_header_host head;
 409        struct gfs2_holder j_gh, ji_gh, thaw_gh;
 410        ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
 411        int ro = 0;
 412        unsigned int pass;
 413        int error = 0;
 414        int jlocked = 0;
 415
 416        if (gfs2_withdrawn(sdp)) {
 417                fs_err(sdp, "jid=%u: Recovery not attempted due to withdraw.\n",
 418                       jd->jd_jid);
 419                goto fail;
 420        }
 421        t_start = ktime_get();
 422        if (sdp->sd_args.ar_spectator)
 423                goto fail;
 424        if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
 425                fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
 426                        jd->jd_jid);
 427                jlocked = 1;
 428                /* Acquire the journal lock so we can do recovery */
 429
 430                error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
 431                                          LM_ST_EXCLUSIVE,
 432                                          LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
 433                                          &j_gh);
 434                switch (error) {
 435                case 0:
 436                        break;
 437
 438                case GLR_TRYFAILED:
 439                        fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
 440                        error = 0;
 441                        goto fail;
 442
 443                default:
 444                        goto fail;
 445                }
 446
 447                error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 448                                           LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
 449                if (error)
 450                        goto fail_gunlock_j;
 451        } else {
 452                fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
 453        }
 454
 455        t_jlck = ktime_get();
 456        fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
 457
 458        error = gfs2_jdesc_check(jd);
 459        if (error)
 460                goto fail_gunlock_ji;
 461
 462        error = gfs2_find_jhead(jd, &head, true);
 463        if (error)
 464                goto fail_gunlock_ji;
 465        t_jhd = ktime_get();
 466        fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
 467                ktime_ms_delta(t_jhd, t_jlck));
 468
 469        if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 470                fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
 471                        jd->jd_jid);
 472
 473                /* Acquire a shared hold on the freeze lock */
 474
 475                error = gfs2_freeze_lock(sdp, &thaw_gh, LM_FLAG_PRIORITY);
 476                if (error)
 477                        goto fail_gunlock_ji;
 478
 479                if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
 480                        ro = 1;
 481                } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
 482                        if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 483                                ro = 1;
 484                } else {
 485                        if (sb_rdonly(sdp->sd_vfs)) {
 486                                /* check if device itself is read-only */
 487                                ro = bdev_read_only(sdp->sd_vfs->s_bdev);
 488                                if (!ro) {
 489                                        fs_info(sdp, "recovery required on "
 490                                                "read-only filesystem.\n");
 491                                        fs_info(sdp, "write access will be "
 492                                                "enabled during recovery.\n");
 493                                }
 494                        }
 495                }
 496
 497                if (ro) {
 498                        fs_warn(sdp, "jid=%u: Can't replay: read-only block "
 499                                "device\n", jd->jd_jid);
 500                        error = -EROFS;
 501                        goto fail_gunlock_thaw;
 502                }
 503
 504                t_tlck = ktime_get();
 505                fs_info(sdp, "jid=%u: Replaying journal...0x%x to 0x%x\n",
 506                        jd->jd_jid, head.lh_tail, head.lh_blkno);
 507
 508                /* We take the sd_log_flush_lock here primarily to prevent log
 509                 * flushes and simultaneous journal replays from stomping on
 510                 * each other wrt jd_log_bio. */
 511                down_read(&sdp->sd_log_flush_lock);
 512                for (pass = 0; pass < 2; pass++) {
 513                        lops_before_scan(jd, &head, pass);
 514                        error = foreach_descriptor(jd, head.lh_tail,
 515                                                   head.lh_blkno, pass);
 516                        lops_after_scan(jd, error, pass);
 517                        if (error) {
 518                                up_read(&sdp->sd_log_flush_lock);
 519                                goto fail_gunlock_thaw;
 520                        }
 521                }
 522
 523                recover_local_statfs(jd, &head);
 524                clean_journal(jd, &head);
 525                up_read(&sdp->sd_log_flush_lock);
 526
 527                gfs2_freeze_unlock(&thaw_gh);
 528                t_rep = ktime_get();
 529                fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
 530                        "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
 531                        jd->jd_jid, ktime_ms_delta(t_rep, t_start),
 532                        ktime_ms_delta(t_jlck, t_start),
 533                        ktime_ms_delta(t_jhd, t_jlck),
 534                        ktime_ms_delta(t_tlck, t_jhd),
 535                        ktime_ms_delta(t_rep, t_tlck));
 536        }
 537
 538        gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
 539
 540        if (jlocked) {
 541                gfs2_glock_dq_uninit(&ji_gh);
 542                gfs2_glock_dq_uninit(&j_gh);
 543        }
 544
 545        fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
 546        goto done;
 547
 548fail_gunlock_thaw:
 549        gfs2_freeze_unlock(&thaw_gh);
 550fail_gunlock_ji:
 551        if (jlocked) {
 552                gfs2_glock_dq_uninit(&ji_gh);
 553fail_gunlock_j:
 554                gfs2_glock_dq_uninit(&j_gh);
 555        }
 556
 557        fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
 558fail:
 559        jd->jd_recover_error = error;
 560        gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
 561done:
 562        clear_bit(JDF_RECOVERY, &jd->jd_flags);
 563        smp_mb__after_atomic();
 564        wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
 565}
 566
 567int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
 568{
 569        int rv;
 570
 571        if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
 572                return -EBUSY;
 573
 574        /* we have JDF_RECOVERY, queue should always succeed */
 575        rv = queue_work(gfs_recovery_wq, &jd->jd_work);
 576        BUG_ON(!rv);
 577
 578        if (wait)
 579                wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 580                            TASK_UNINTERRUPTIBLE);
 581
 582        return wait ? jd->jd_recover_error : 0;
 583}
 584
 585
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