diff options
author | David Teigland <teigland@redhat.com> | 2006-01-16 16:50:04 (GMT) |
---|---|---|
committer | Steven Whitehouse <swhiteho@redhat.com> | 2006-01-16 16:50:04 (GMT) |
commit | b3b94faa5fe5968827ba0640ee9fba4b3e7f736e (patch) | |
tree | 70bd6068b050d2c46e338484f8b03fae4365c6c3 /fs/gfs2/recovery.c | |
parent | f7825dcf8c7301cfd3724eb40c5b443cc85ab7b8 (diff) | |
download | linux-b3b94faa5fe5968827ba0640ee9fba4b3e7f736e.tar.xz |
[GFS2] The core of GFS2
This patch contains all the core files for GFS2.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/recovery.c')
-rw-r--r-- | fs/gfs2/recovery.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c new file mode 100644 index 0000000..15cd26f --- /dev/null +++ b/fs/gfs2/recovery.c @@ -0,0 +1,570 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <asm/semaphore.h> + +#include "gfs2.h" +#include "bmap.h" +#include "glock.h" +#include "glops.h" +#include "lm.h" +#include "lops.h" +#include "meta_io.h" +#include "recovery.h" +#include "super.h" + +int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk, + struct buffer_head **bh) +{ + struct gfs2_glock *gl = jd->jd_inode->i_gl; + int new = 0; + uint64_t dblock; + uint32_t extlen; + int error; + + error = gfs2_block_map(jd->jd_inode, blk, &new, &dblock, &extlen); + if (error) + return error; + if (!dblock) { + gfs2_consist_inode(jd->jd_inode); + return -EIO; + } + + gfs2_meta_ra(gl, dblock, extlen); + error = gfs2_meta_read(gl, dblock, DIO_START | DIO_WAIT, bh); + + return error; +} + +int gfs2_revoke_add(struct gfs2_sbd *sdp, uint64_t blkno, unsigned int where) +{ + struct list_head *head = &sdp->sd_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_KERNEL); + 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_sbd *sdp, uint64_t blkno, unsigned int where) +{ + struct gfs2_revoke_replay *rr; + int wrap, a, b, revoke; + int found = 0; + + list_for_each_entry(rr, &sdp->sd_revoke_list, rr_list) { + if (rr->rr_blkno == blkno) { + found = 1; + break; + } + } + + if (!found) + return 0; + + wrap = (rr->rr_where < sdp->sd_replay_tail); + a = (sdp->sd_replay_tail < where); + b = (where < rr->rr_where); + revoke = (wrap) ? (a || b) : (a && b); + + return revoke; +} + +void gfs2_revoke_clean(struct gfs2_sbd *sdp) +{ + struct list_head *head = &sdp->sd_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 *head) +{ + struct buffer_head *bh; + struct gfs2_log_header lh; + uint32_t hash; + int error; + + error = gfs2_replay_read_block(jd, blk, &bh); + if (error) + return error; + + memcpy(&lh, bh->b_data, sizeof(struct gfs2_log_header)); + lh.lh_hash = 0; + hash = gfs2_disk_hash((char *)&lh, sizeof(struct gfs2_log_header)); + gfs2_log_header_in(&lh, bh->b_data); + + brelse(bh); + + if (lh.lh_header.mh_magic != GFS2_MAGIC || + lh.lh_header.mh_type != GFS2_METATYPE_LH || + lh.lh_blkno != blk || + lh.lh_hash != hash) + return 1; + + *head = lh; + + return 0; +} + +/** + * 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 *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(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 *head) +{ + unsigned int blk = head->lh_blkno; + struct gfs2_log_header 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(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 *head) +{ + struct gfs2_log_header lh_1, lh_m; + uint32_t 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 = jd->jd_inode->i_sbd; + 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 (be16_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) { + struct gfs2_log_header lh; + error = get_log_header(jd, start, &lh); + if (!error) { + gfs2_replay_incr_blk(sdp, &start); + continue; + } + if (error == 1) { + gfs2_consist_inode(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(sdp, &start); + + brelse(bh); + } + + return 0; +} + +/** + * clean_journal - mark a dirty journal as being clean + * @sdp: the filesystem + * @jd: the journal + * @gl: the journal's glock + * @head: the head journal to start from + * + * Returns: errno + */ + +static int clean_journal(struct gfs2_jdesc *jd, struct gfs2_log_header *head) +{ + struct gfs2_inode *ip = jd->jd_inode; + struct gfs2_sbd *sdp = ip->i_sbd; + unsigned int lblock; + int new = 0; + uint64_t dblock; + struct gfs2_log_header *lh; + uint32_t hash; + struct buffer_head *bh; + int error; + + lblock = head->lh_blkno; + gfs2_replay_incr_blk(sdp, &lblock); + error = gfs2_block_map(ip, lblock, &new, &dblock, NULL); + if (error) + return error; + if (!dblock) { + gfs2_consist_inode(ip); + return -EIO; + } + + bh = sb_getblk(sdp->sd_vfs, dblock); + lock_buffer(bh); + memset(bh->b_data, 0, bh->b_size); + set_buffer_uptodate(bh); + clear_buffer_dirty(bh); + unlock_buffer(bh); + + lh = (struct gfs2_log_header *)bh->b_data; + memset(lh, 0, sizeof(struct gfs2_log_header)); + lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); + lh->lh_header.mh_type = cpu_to_be16(GFS2_METATYPE_LH); + lh->lh_header.mh_format = cpu_to_be16(GFS2_FORMAT_LH); + lh->lh_sequence = cpu_to_be64(head->lh_sequence + 1); + lh->lh_flags = cpu_to_be32(GFS2_LOG_HEAD_UNMOUNT); + lh->lh_blkno = cpu_to_be32(lblock); + hash = gfs2_disk_hash((const char *)lh, sizeof(struct gfs2_log_header)); + lh->lh_hash = cpu_to_be32(hash); + + set_buffer_dirty(bh); + if (sync_dirty_buffer(bh)) + gfs2_io_error_bh(sdp, bh); + brelse(bh); + + return error; +} + +/** + * gfs2_recover_journal - recovery a given journal + * @jd: the struct gfs2_jdesc describing the journal + * @wait: Don't return until the journal is clean (or an error is encountered) + * + * Acquire the journal's lock, check to see if the journal is clean, and + * do recovery if necessary. + * + * Returns: errno + */ + +int gfs2_recover_journal(struct gfs2_jdesc *jd, int wait) +{ + struct gfs2_sbd *sdp = jd->jd_inode->i_sbd; + struct gfs2_log_header head; + struct gfs2_holder j_gh, ji_gh, t_gh; + unsigned long t; + int ro = 0; + unsigned int pass; + int error; + + fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n", jd->jd_jid); + + /* Aquire 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 | + ((wait) ? 0 : 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(jd->jd_inode->i_gl, LM_ST_SHARED, + LM_FLAG_NOEXP, &ji_gh); + if (error) + goto fail_gunlock_j; + + 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; + + if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) { + fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n", + jd->jd_jid); + + t = jiffies; + + /* Acquire a shared hold on the transaction lock */ + + error = gfs2_glock_nq_init(sdp->sd_trans_gl, + LM_ST_SHARED, + LM_FLAG_NOEXP | + LM_FLAG_PRIORITY | + GL_NEVER_RECURSE | + GL_NOCANCEL | + GL_NOCACHE, + &t_gh); + if (error) + goto fail_gunlock_ji; + + if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) { + if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) + ro = 1; + } else { + if (sdp->sd_vfs->s_flags & MS_RDONLY) + ro = 1; + } + + if (ro) { + fs_warn(sdp, "jid=%u: Can't replay: read-only FS\n", + jd->jd_jid); + error = -EROFS; + goto fail_gunlock_tr; + } + + 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_tr; + } + + error = clean_journal(jd, &head); + if (error) + goto fail_gunlock_tr; + + gfs2_glock_dq_uninit(&t_gh); + + t = DIV_RU(jiffies - t, HZ); + + fs_info(sdp, "jid=%u: Journal replayed in %lus\n", + jd->jd_jid, t); + } + + gfs2_glock_dq_uninit(&ji_gh); + + gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS); + + gfs2_glock_dq_uninit(&j_gh); + + fs_info(sdp, "jid=%u: Done\n", jd->jd_jid); + + return 0; + + fail_gunlock_tr: + gfs2_glock_dq_uninit(&t_gh); + + fail_gunlock_ji: + 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: + gfs2_lm_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP); + + return error; +} + +/** + * gfs2_check_journals - Recover any dirty journals + * @sdp: the filesystem + * + */ + +void gfs2_check_journals(struct gfs2_sbd *sdp) +{ + struct gfs2_jdesc *jd; + + for (;;) { + jd = gfs2_jdesc_find_dirty(sdp); + if (!jd) + break; + + if (jd != sdp->sd_jdesc) + gfs2_recover_journal(jd, NO_WAIT); + } +} + |