diff options
Diffstat (limited to 'fs/gfs2/recovery.c')
-rw-r--r-- | fs/gfs2/recovery.c | 572 |
1 files changed, 572 insertions, 0 deletions
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c new file mode 100644 index 000000000..0f501f938 --- /dev/null +++ b/fs/gfs2/recovery.c @@ -0,0 +1,572 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License version 2. + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <linux/gfs2_ondisk.h> +#include <linux/crc32.h> +#include <linux/crc32c.h> +#include <linux/ktime.h> + +#include "gfs2.h" +#include "incore.h" +#include "bmap.h" +#include "glock.h" +#include "glops.h" +#include "log.h" +#include "lops.h" +#include "meta_io.h" +#include "recovery.h" +#include "super.h" +#include "util.h" +#include "dir.h" + +struct workqueue_struct *gfs_recovery_wq; + +int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk, + struct buffer_head **bh) +{ + struct gfs2_inode *ip = GFS2_I(jd->jd_inode); + struct gfs2_glock *gl = ip->i_gl; + int new = 0; + u64 dblock; + u32 extlen; + int error; + + error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen); + if (error) + return error; + if (!dblock) { + gfs2_consist_inode(ip); + return -EIO; + } + + *bh = gfs2_meta_ra(gl, dblock, extlen); + + return error; +} + +int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where) +{ + struct list_head *head = &jd->jd_revoke_list; + struct gfs2_revoke_replay *rr; + int found = 0; + + list_for_each_entry(rr, head, rr_list) { + if (rr->rr_blkno == blkno) { + found = 1; + break; + } + } + + if (found) { + rr->rr_where = where; + return 0; + } + + rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS); + if (!rr) + return -ENOMEM; + + rr->rr_blkno = blkno; + rr->rr_where = where; + list_add(&rr->rr_list, head); + + return 1; +} + +int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where) +{ + struct gfs2_revoke_replay *rr; + int wrap, a, b, revoke; + int found = 0; + + list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) { + if (rr->rr_blkno == blkno) { + found = 1; + break; + } + } + + if (!found) + return 0; + + wrap = (rr->rr_where < jd->jd_replay_tail); + a = (jd->jd_replay_tail < where); + b = (where < rr->rr_where); + revoke = (wrap) ? (a || b) : (a && b); + + return revoke; +} + +void gfs2_revoke_clean(struct gfs2_jdesc *jd) +{ + struct list_head *head = &jd->jd_revoke_list; + struct gfs2_revoke_replay *rr; + + while (!list_empty(head)) { + rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list); + list_del(&rr->rr_list); + kfree(rr); + } +} + +/** + * get_log_header - read the log header for a given segment + * @jd: the journal + * @blk: the block to look at + * @lh: the log header to return + * + * Read the log header for a given segement in a given journal. Do a few + * sanity checks on it. + * + * Returns: 0 on success, + * 1 if the header was invalid or incomplete, + * errno on error + */ + +static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk, + struct gfs2_log_header_host *head) +{ + struct gfs2_log_header *lh; + struct buffer_head *bh; + u32 hash, crc; + int error; + + error = gfs2_replay_read_block(jd, blk, &bh); + if (error) + return error; + lh = (void *)bh->b_data; + + hash = crc32(~0, lh, LH_V1_SIZE - 4); + hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */ + + crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4, + bh->b_size - LH_V1_SIZE - 4); + + error = lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) || + lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) || + be32_to_cpu(lh->lh_blkno) != blk || + be32_to_cpu(lh->lh_hash) != hash || + (lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc); + + brelse(bh); + + if (!error) { + head->lh_sequence = be64_to_cpu(lh->lh_sequence); + head->lh_flags = be32_to_cpu(lh->lh_flags); + head->lh_tail = be32_to_cpu(lh->lh_tail); + head->lh_blkno = be32_to_cpu(lh->lh_blkno); + } + return error; +} + +/** + * find_good_lh - find a good log header + * @jd: the journal + * @blk: the segment to start searching from + * @lh: the log header to fill in + * @forward: if true search forward in the log, else search backward + * + * Call get_log_header() to get a log header for a segment, but if the + * segment is bad, either scan forward or backward until we find a good one. + * + * Returns: errno + */ + +static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk, + struct gfs2_log_header_host *head) +{ + unsigned int orig_blk = *blk; + int error; + + for (;;) { + error = get_log_header(jd, *blk, head); + if (error <= 0) + return error; + + if (++*blk == jd->jd_blocks) + *blk = 0; + + if (*blk == orig_blk) { + gfs2_consist_inode(GFS2_I(jd->jd_inode)); + return -EIO; + } + } +} + +/** + * jhead_scan - make sure we've found the head of the log + * @jd: the journal + * @head: this is filled in with the log descriptor of the head + * + * At this point, seg and lh should be either the head of the log or just + * before. Scan forward until we find the head. + * + * Returns: errno + */ + +static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) +{ + unsigned int blk = head->lh_blkno; + struct gfs2_log_header_host lh; + int error; + + for (;;) { + if (++blk == jd->jd_blocks) + blk = 0; + + error = get_log_header(jd, blk, &lh); + if (error < 0) + return error; + if (error == 1) + continue; + + if (lh.lh_sequence == head->lh_sequence) { + gfs2_consist_inode(GFS2_I(jd->jd_inode)); + return -EIO; + } + if (lh.lh_sequence < head->lh_sequence) + break; + + *head = lh; + } + + return 0; +} + +/** + * gfs2_find_jhead - find the head of a log + * @jd: the journal + * @head: the log descriptor for the head of the log is returned here + * + * Do a binary search of a journal and find the valid log entry with the + * highest sequence number. (i.e. the log head) + * + * Returns: errno + */ + +int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) +{ + struct gfs2_log_header_host lh_1, lh_m; + u32 blk_1, blk_2, blk_m; + int error; + + blk_1 = 0; + blk_2 = jd->jd_blocks - 1; + + for (;;) { + blk_m = (blk_1 + blk_2) / 2; + + error = find_good_lh(jd, &blk_1, &lh_1); + if (error) + return error; + + error = find_good_lh(jd, &blk_m, &lh_m); + if (error) + return error; + + if (blk_1 == blk_m || blk_m == blk_2) + break; + + if (lh_1.lh_sequence <= lh_m.lh_sequence) + blk_1 = blk_m; + else + blk_2 = blk_m; + } + + error = jhead_scan(jd, &lh_1); + if (error) + return error; + + *head = lh_1; + + return error; +} + +/** + * foreach_descriptor - go through the active part of the log + * @jd: the journal + * @start: the first log header in the active region + * @end: the last log header (don't process the contents of this entry)) + * + * Call a given function once for every log descriptor in the active + * portion of the log. + * + * Returns: errno + */ + +static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start, + unsigned int end, int pass) +{ + struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); + struct buffer_head *bh; + struct gfs2_log_descriptor *ld; + int error = 0; + u32 length; + __be64 *ptr; + unsigned int offset = sizeof(struct gfs2_log_descriptor); + offset += sizeof(__be64) - 1; + offset &= ~(sizeof(__be64) - 1); + + while (start != end) { + error = gfs2_replay_read_block(jd, start, &bh); + if (error) + return error; + if (gfs2_meta_check(sdp, bh)) { + brelse(bh); + return -EIO; + } + ld = (struct gfs2_log_descriptor *)bh->b_data; + length = be32_to_cpu(ld->ld_length); + + if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) { + struct gfs2_log_header_host lh; + error = get_log_header(jd, start, &lh); + if (!error) { + gfs2_replay_incr_blk(jd, &start); + brelse(bh); + continue; + } + if (error == 1) { + gfs2_consist_inode(GFS2_I(jd->jd_inode)); + error = -EIO; + } + brelse(bh); + return error; + } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) { + brelse(bh); + return -EIO; + } + ptr = (__be64 *)(bh->b_data + offset); + error = lops_scan_elements(jd, start, ld, ptr, pass); + if (error) { + brelse(bh); + return error; + } + + while (length--) + gfs2_replay_incr_blk(jd, &start); + + brelse(bh); + } + + return 0; +} + +/** + * clean_journal - mark a dirty journal as being clean + * @jd: the journal + * @head: the head journal to start from + * + * Returns: errno + */ + +static void clean_journal(struct gfs2_jdesc *jd, + struct gfs2_log_header_host *head) +{ + struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); + + sdp->sd_log_flush_head = head->lh_blkno; + gfs2_replay_incr_blk(jd, &sdp->sd_log_flush_head); + gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, + GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY, + REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC); +} + + +static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid, + unsigned int message) +{ + char env_jid[20]; + char env_status[20]; + char *envp[] = { env_jid, env_status, NULL }; + struct lm_lockstruct *ls = &sdp->sd_lockstruct; + + ls->ls_recover_jid_done = jid; + ls->ls_recover_jid_status = message; + sprintf(env_jid, "JID=%u", jid); + sprintf(env_status, "RECOVERY=%s", + message == LM_RD_SUCCESS ? "Done" : "Failed"); + kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp); + + if (sdp->sd_lockstruct.ls_ops->lm_recovery_result) + sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message); +} + +void gfs2_recover_func(struct work_struct *work) +{ + struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work); + struct gfs2_inode *ip = GFS2_I(jd->jd_inode); + struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); + struct gfs2_log_header_host head; + struct gfs2_holder j_gh, ji_gh, thaw_gh; + ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep; + int ro = 0; + unsigned int pass; + int error = 0; + int jlocked = 0; + + t_start = ktime_get(); + if (sdp->sd_args.ar_spectator) + goto fail; + if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) { + fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n", + jd->jd_jid); + jlocked = 1; + /* Acquire the journal lock so we can do recovery */ + + error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops, + LM_ST_EXCLUSIVE, + LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE, + &j_gh); + switch (error) { + case 0: + break; + + case GLR_TRYFAILED: + fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid); + error = 0; + + default: + goto fail; + }; + + error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, + LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh); + if (error) + goto fail_gunlock_j; + } else { + fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid); + } + + t_jlck = ktime_get(); + fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid); + + error = gfs2_jdesc_check(jd); + if (error) + goto fail_gunlock_ji; + + error = gfs2_find_jhead(jd, &head); + if (error) + goto fail_gunlock_ji; + t_jhd = ktime_get(); + + if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) { + fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n", + jd->jd_jid); + + /* Acquire a shared hold on the freeze lock */ + + error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, + LM_FLAG_NOEXP | LM_FLAG_PRIORITY, + &thaw_gh); + if (error) + goto fail_gunlock_ji; + + if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) { + ro = 1; + } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) { + if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) + ro = 1; + } else { + if (sb_rdonly(sdp->sd_vfs)) { + /* check if device itself is read-only */ + ro = bdev_read_only(sdp->sd_vfs->s_bdev); + if (!ro) { + fs_info(sdp, "recovery required on " + "read-only filesystem.\n"); + fs_info(sdp, "write access will be " + "enabled during recovery.\n"); + } + } + } + + if (ro) { + fs_warn(sdp, "jid=%u: Can't replay: read-only block " + "device\n", jd->jd_jid); + error = -EROFS; + goto fail_gunlock_thaw; + } + + t_tlck = ktime_get(); + fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid); + + for (pass = 0; pass < 2; pass++) { + lops_before_scan(jd, &head, pass); + error = foreach_descriptor(jd, head.lh_tail, + head.lh_blkno, pass); + lops_after_scan(jd, error, pass); + if (error) + goto fail_gunlock_thaw; + } + + clean_journal(jd, &head); + + gfs2_glock_dq_uninit(&thaw_gh); + t_rep = ktime_get(); + fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, " + "jhead:%lldms, tlck:%lldms, replay:%lldms]\n", + jd->jd_jid, ktime_ms_delta(t_rep, t_start), + ktime_ms_delta(t_jlck, t_start), + ktime_ms_delta(t_jhd, t_jlck), + ktime_ms_delta(t_tlck, t_jhd), + ktime_ms_delta(t_rep, t_tlck)); + } + + gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS); + + if (jlocked) { + gfs2_glock_dq_uninit(&ji_gh); + gfs2_glock_dq_uninit(&j_gh); + } + + fs_info(sdp, "jid=%u: Done\n", jd->jd_jid); + goto done; + +fail_gunlock_thaw: + gfs2_glock_dq_uninit(&thaw_gh); +fail_gunlock_ji: + if (jlocked) { + gfs2_glock_dq_uninit(&ji_gh); +fail_gunlock_j: + gfs2_glock_dq_uninit(&j_gh); + } + + fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done"); +fail: + jd->jd_recover_error = error; + gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP); +done: + clear_bit(JDF_RECOVERY, &jd->jd_flags); + smp_mb__after_atomic(); + wake_up_bit(&jd->jd_flags, JDF_RECOVERY); +} + +int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait) +{ + int rv; + + if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags)) + return -EBUSY; + + /* we have JDF_RECOVERY, queue should always succeed */ + rv = queue_work(gfs_recovery_wq, &jd->jd_work); + BUG_ON(!rv); + + if (wait) + wait_on_bit(&jd->jd_flags, JDF_RECOVERY, + TASK_UNINTERRUPTIBLE); + + return wait ? jd->jd_recover_error : 0; +} + |