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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/gfs2/recovery.c
Initial import
Diffstat (limited to 'fs/gfs2/recovery.c')
-rw-r--r--fs/gfs2/recovery.c611
1 files changed, 611 insertions, 0 deletions
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
new file mode 100644
index 000000000..1b645773c
--- /dev/null
+++ b/fs/gfs2/recovery.c
@@ -0,0 +1,611 @@
+/*
+ * 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 "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "glock.h"
+#include "glops.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);
+ }
+}
+
+static int gfs2_log_header_in(struct gfs2_log_header_host *lh, const void *buf)
+{
+ const struct gfs2_log_header *str = buf;
+
+ if (str->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
+ str->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH))
+ return 1;
+
+ lh->lh_sequence = be64_to_cpu(str->lh_sequence);
+ lh->lh_flags = be32_to_cpu(str->lh_flags);
+ lh->lh_tail = be32_to_cpu(str->lh_tail);
+ lh->lh_blkno = be32_to_cpu(str->lh_blkno);
+ lh->lh_hash = be32_to_cpu(str->lh_hash);
+ return 0;
+}
+
+/**
+ * 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 buffer_head *bh;
+ struct gfs2_log_header_host uninitialized_var(lh);
+ const u32 nothing = 0;
+ u32 hash;
+ int error;
+
+ error = gfs2_replay_read_block(jd, blk, &bh);
+ if (error)
+ return error;
+
+ hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) -
+ sizeof(u32));
+ hash = crc32_le(hash, (unsigned char const *)&nothing, sizeof(nothing));
+ hash ^= (u32)~0;
+ error = gfs2_log_header_in(&lh, bh->b_data);
+ brelse(bh);
+
+ if (error || 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_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(sdp, &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(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_host *head)
+{
+ struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
+ struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
+ unsigned int lblock;
+ struct gfs2_log_header *lh;
+ u32 hash;
+ struct buffer_head *bh;
+ int error;
+ struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
+
+ lblock = head->lh_blkno;
+ gfs2_replay_incr_blk(sdp, &lblock);
+ bh_map.b_size = 1 << ip->i_inode.i_blkbits;
+ error = gfs2_block_map(&ip->i_inode, lblock, &bh_map, 0);
+ if (error)
+ return error;
+ if (!bh_map.b_blocknr) {
+ gfs2_consist_inode(ip);
+ return -EIO;
+ }
+
+ bh = sb_getblk(sdp->sd_vfs, bh_map.b_blocknr);
+ 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_be32(GFS2_METATYPE_LH);
+ lh->lh_header.__pad0 = cpu_to_be64(0);
+ lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
+ lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
+ 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;
+}
+
+
+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;
+ unsigned long t;
+ int ro = 0;
+ unsigned int pass;
+ int error;
+ int jlocked = 0;
+
+ if (sdp->sd_args.ar_spectator ||
+ (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);
+ }
+
+ 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 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 (sdp->sd_vfs->s_flags & MS_RDONLY) {
+ /* 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;
+ }
+
+ 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;
+ }
+
+ error = clean_journal(jd, &head);
+ if (error)
+ goto fail_gunlock_thaw;
+
+ gfs2_glock_dq_uninit(&thaw_gh);
+ t = DIV_ROUND_UP(jiffies - t, HZ);
+ fs_info(sdp, "jid=%u: Journal replayed in %lus\n",
+ jd->jd_jid, t);
+ }
+
+ 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;
+}
+