*
* Written by Stephen C. Tweedie <sct@redhat.com>, 1999
*
- * Copyright 1999 Red Hat Software --- All Rights Reserved
+ * Copyright 1999-2000 Red Hat Software --- All Rights Reserved
*
* This file is part of the Linux kernel and is made available under
* the terms of the GNU General Public License, version 2, or at your
*/
#ifndef __KERNEL__
-#include "jfs.h"
+#include "jfs_user.h"
#else
-#include <linux/sched.h>
+#include <linux/time.h>
#include <linux/fs.h>
-#include <linux/jfs.h>
+#include <linux/jbd.h>
#include <linux/errno.h>
-#include <linux/malloc.h>
-#include <linux/locks.h>
-#include <linux/buffer.h>
+#include <linux/slab.h>
+#endif
+
+/*
+ * Maintain information about the progress of the recovery job, so that
+ * the different passes can carry information between them.
+ */
+struct recovery_info
+{
+ tid_t start_transaction;
+ tid_t end_transaction;
+
+ int nr_replays;
+ int nr_revokes;
+ int nr_revoke_hits;
+};
+
+enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY};
+static int do_one_pass(journal_t *journal,
+ struct recovery_info *info, enum passtype pass);
+static int scan_revoke_records(journal_t *, struct buffer_head *,
+ tid_t, struct recovery_info *);
+#ifdef __KERNEL__
/* Release readahead buffers after use */
-static void brelse_array(struct buffer_head *b[], int n)
+void journal_brelse_array(struct buffer_head *b[], int n)
{
while (--n >= 0)
brelse (b[n]);
* fixed value.
*/
+#define MAXBUF 8
static int do_readahead(journal_t *journal, unsigned int start)
{
int err;
- unsigned int max, nbufs, next, blocknr;
+ unsigned int max, nbufs, next;
+ unsigned long blocknr;
struct buffer_head *bh;
- #define MAXBUF 8
struct buffer_head * bufs[MAXBUF];
/* Do up to 128K of readahead */
nbufs = 0;
for (next = start; next < max; next++) {
- blocknr = next;
- if (journal->j_inode)
- blocknr = bmap(journal->j_inode, next);
- if (!blocknr) {
- printk (KERN_ERR "JFS: bad block at offset %u\n",
+ err = journal_bmap(journal, next, &blocknr);
+
+ if (err) {
+ printk (KERN_ERR "JBD: bad block at offset %u\n",
next);
- err = -EIO;
goto failed;
}
-
- bh = getblk(journal->j_dev, blocknr, journal->j_blocksize);
+
+ bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
if (!bh) {
- printk(KERN_ERR "JFS: readahead getblk failed\n");
err = -ENOMEM;
goto failed;
}
bufs[nbufs++] = bh;
if (nbufs == MAXBUF) {
ll_rw_block(READ, nbufs, bufs);
- brelse_array(bufs, nbufs);
+ journal_brelse_array(bufs, nbufs);
nbufs = 0;
}
} else
if (nbufs)
ll_rw_block(READ, nbufs, bufs);
err = 0;
-
+
failed:
if (nbufs)
- brelse_array(bufs, nbufs);
+ journal_brelse_array(bufs, nbufs);
return err;
}
-#endif
+
+#endif /* __KERNEL__ */
+
/*
* Read a block from the journal
static int jread(struct buffer_head **bhp, journal_t *journal,
unsigned int offset)
{
- unsigned int blocknr;
+ int err;
+ unsigned long blocknr;
struct buffer_head *bh;
*bhp = NULL;
- if (offset >= journal->j_maxlen)
- return -EINVAL;
-
- blocknr = offset;
- if (journal->j_inode)
- blocknr = bmap(journal->j_inode, offset);
+ J_ASSERT (offset < journal->j_maxlen);
- if (!blocknr) {
- printk (KERN_ERR "JFS: bad block at offset %u\n",
+ err = journal_bmap(journal, offset, &blocknr);
+
+ if (err) {
+ printk (KERN_ERR "JBD: bad block at offset %u\n",
offset);
- return -EIO;
+ return err;
}
-
- bh = getblk(journal->j_dev, blocknr, journal->j_blocksize);
+
+ bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
if (!bh)
return -ENOMEM;
-
+
if (!buffer_uptodate(bh)) {
/* If this is a brand new buffer, start readahead.
Otherwise, we assume we are already reading it. */
do_readahead(journal, offset);
wait_on_buffer(bh);
}
-
+
if (!buffer_uptodate(bh)) {
- printk (KERN_ERR "JFS: Failed to read block at offset %u\n",
+ printk (KERN_ERR "JBD: Failed to read block at offset %u\n",
offset);
brelse(bh);
return -EIO;
}
-
+
*bhp = bh;
return 0;
}
* Count the number of in-use tags in a journal descriptor block.
*/
-int count_tags(struct buffer_head *bh, int size)
+static int count_tags(struct buffer_head *bh, int size)
{
char * tagp;
journal_block_tag_t * tag;
int nr = 0;
-
+
tagp = &bh->b_data[sizeof(journal_header_t)];
-
+
while ((tagp - bh->b_data + sizeof(journal_block_tag_t)) <= size) {
tag = (journal_block_tag_t *) tagp;
-
+
nr++;
tagp += sizeof(journal_block_tag_t);
if (!(tag->t_flags & htonl(JFS_FLAG_SAME_UUID)))
if (tag->t_flags & htonl(JFS_FLAG_LAST_TAG))
break;
}
-
+
return nr;
}
var -= ((journal)->j_last - (journal)->j_first); \
} while (0)
-/*
- * journal_recover
+/**
+ * int journal_recover(journal_t *journal) - recovers a on-disk journal
+ * @journal: the journal to recover
*
* The primary function for recovering the log contents when mounting a
* journaled device.
+ *
+ * Recovery is done in three passes. In the first pass, we look for the
+ * end of the log. In the second, we assemble the list of revoke
+ * blocks. In the third and final pass, we replay any un-revoked blocks
+ * in the log.
*/
-
int journal_recover(journal_t *journal)
{
+ int err;
+ journal_superblock_t * sb;
+
+ struct recovery_info info;
+
+ memset(&info, 0, sizeof(info));
+ sb = journal->j_superblock;
+
+ /*
+ * The journal superblock's s_start field (the current log head)
+ * is always zero if, and only if, the journal was cleanly
+ * unmounted.
+ */
+
+ if (!sb->s_start) {
+ jbd_debug(1, "No recovery required, last transaction %d\n",
+ (int)ntohl(sb->s_sequence));
+ journal->j_transaction_sequence = ntohl(sb->s_sequence) + 1;
+ return 0;
+ }
+
+ err = do_one_pass(journal, &info, PASS_SCAN);
+ if (!err)
+ err = do_one_pass(journal, &info, PASS_REVOKE);
+ if (!err)
+ err = do_one_pass(journal, &info, PASS_REPLAY);
+
+ jbd_debug(0, "JBD: recovery, exit status %d, "
+ "recovered transactions %u to %u\n",
+ err, info.start_transaction, info.end_transaction);
+ jbd_debug(0, "JBD: Replayed %d and revoked %d/%d blocks\n",
+ info.nr_replays, info.nr_revoke_hits, info.nr_revokes);
+
+ /* Restart the log at the next transaction ID, thus invalidating
+ * any existing commit records in the log. */
+ journal->j_transaction_sequence = ++info.end_transaction;
+
+ journal_clear_revoke(journal);
+ sync_blockdev(journal->j_fs_dev);
+ return err;
+}
+
+/**
+ * int journal_skip_recovery() - Start journal and wipe exiting records
+ * @journal: journal to startup
+ *
+ * Locate any valid recovery information from the journal and set up the
+ * journal structures in memory to ignore it (presumably because the
+ * caller has evidence that it is out of date).
+ * This function does'nt appear to be exorted..
+ *
+ * We perform one pass over the journal to allow us to tell the user how
+ * much recovery information is being erased, and to let us initialise
+ * the journal transaction sequence numbers to the next unused ID.
+ */
+int journal_skip_recovery(journal_t *journal)
+{
+ int err;
+ journal_superblock_t * sb;
+
+ struct recovery_info info;
+
+ memset (&info, 0, sizeof(info));
+ sb = journal->j_superblock;
+
+ err = do_one_pass(journal, &info, PASS_SCAN);
+
+ if (err) {
+ printk(KERN_ERR "JBD: error %d scanning journal\n", err);
+ ++journal->j_transaction_sequence;
+ } else {
+#ifdef CONFIG_JBD_DEBUG
+ int dropped = info.end_transaction - ntohl(sb->s_sequence);
+#endif
+ jbd_debug(0,
+ "JBD: ignoring %d transaction%s from the journal.\n",
+ dropped, (dropped == 1) ? "" : "s");
+ journal->j_transaction_sequence = ++info.end_transaction;
+ }
+
+ journal->j_tail = 0;
+ return err;
+}
+
+static int do_one_pass(journal_t *journal,
+ struct recovery_info *info, enum passtype pass)
+{
unsigned int first_commit_ID, next_commit_ID;
unsigned long next_log_block;
- unsigned long transaction_start;
int err, success = 0;
- journal_superblock_t * jsb;
+ journal_superblock_t * sb;
journal_header_t * tmp;
struct buffer_head * bh;
-
+ unsigned int sequence;
+ int blocktype;
+
/* Precompute the maximum metadata descriptors in a descriptor block */
int MAX_BLOCKS_PER_DESC;
MAX_BLOCKS_PER_DESC = ((journal->j_blocksize-sizeof(journal_header_t))
* block offsets): query the superblock.
*/
- jsb = journal->j_superblock;
- next_commit_ID = ntohl(jsb->s_sequence);
- next_log_block = ntohl(jsb->s_start);
+ sb = journal->j_superblock;
+ next_commit_ID = ntohl(sb->s_sequence);
+ next_log_block = ntohl(sb->s_start);
first_commit_ID = next_commit_ID;
-
- /*
- * The journal superblock's s_start field (the current log head)
- * is always zero if, and only if, the journal was cleanly
- * unmounted.
- */
+ if (pass == PASS_SCAN)
+ info->start_transaction = first_commit_ID;
+
+ jbd_debug(1, "Starting recovery pass %d\n", pass);
- if (!jsb->s_start) {
- jfs_debug(1, "No recovery required, last transaction %d\n",
- ntohl(jsb->s_sequence));
- journal->j_transaction_sequence = ++next_commit_ID;
- return 0;
- }
-
- jfs_debug(1, "Starting recovery\n");
-
/*
* Now we walk through the log, transaction by transaction,
* making sure that each transaction has a commit block in the
* into the main filesystem.
*/
- while (1) {
- jfs_debug(2, "Looking for commit ID %u at %lu/%lu\n",
+ while (1) {
+ int flags;
+ char * tagp;
+ journal_block_tag_t * tag;
+ struct buffer_head * obh;
+ struct buffer_head * nbh;
+
+ /* If we already know where to stop the log traversal,
+ * check right now that we haven't gone past the end of
+ * the log. */
+
+ if (pass != PASS_SCAN)
+ if (tid_geq(next_commit_ID, info->end_transaction))
+ break;
+
+ jbd_debug(2, "Scanning for sequence ID %u at %lu/%lu\n",
next_commit_ID, next_log_block, journal->j_last);
- transaction_start = next_log_block;
- while (next_log_block < journal->j_last) {
- /* Skip over each chunk of the transaction
- * looking either the next descriptor block or
- * the final commit record. */
+ /* Skip over each chunk of the transaction looking
+ * either the next descriptor block or the final commit
+ * record. */
+
+ jbd_debug(3, "JBD: checking block %ld\n", next_log_block);
+ err = jread(&bh, journal, next_log_block);
+ if (err)
+ goto failed;
- jfs_debug(3, "JFS: checking block %ld\n",
- next_log_block);
- err = jread(&bh, journal, next_log_block);
- if (err)
- goto failed;
-
- /* What kind of buffer is it?
- *
- * If it is a descriptor block, work out the
- * expected location of the next and skip to it.
- *
- * If it is the right commit block, end the
- * search and start recovering the transaction.
- *
- * Any non-control block, or an unexpected
- * control block is interpreted as old data from
- * a previous wrap of the log: stop recovery at
- * this point.
- */
+ next_log_block++;
+ wrap(journal, next_log_block);
- tmp = (journal_header_t *) bh->b_data;
-
- if (tmp->h_magic == htonl(JFS_MAGIC_NUMBER)) {
- int blocktype = ntohl(tmp->h_blocktype);
- jfs_debug(3, "Found magic %d\n", blocktype);
-
- if (blocktype == JFS_DESCRIPTOR_BLOCK) {
- /* Work out where the next descriptor
- * should be. */
- next_log_block++;
- next_log_block += count_tags(bh, journal->j_blocksize);
- wrap(journal, next_log_block);
- brelse(bh);
- continue;
- } else if (blocktype == JFS_COMMIT_BLOCK) {
- unsigned int sequence = tmp->h_sequence;
- brelse(bh);
- if (sequence == htonl(next_commit_ID))
- goto commit;
- jfs_debug(2, "found sequence %d, "
- "expected %d.\n",
- ntohl(sequence),
- next_commit_ID);
- goto finished;
- }
- }
+ /* What kind of buffer is it?
+ *
+ * If it is a descriptor block, check that it has the
+ * expected sequence number. Otherwise, we're all done
+ * here. */
- /* We didn't recognise it? OK, we've gone off
- * the tail of the log in that case. */
+ tmp = (journal_header_t *)bh->b_data;
+
+ if (tmp->h_magic != htonl(JFS_MAGIC_NUMBER)) {
brelse(bh);
break;
}
- goto finished;
+ blocktype = ntohl(tmp->h_blocktype);
+ sequence = ntohl(tmp->h_sequence);
+ jbd_debug(3, "Found magic %d, sequence %d\n",
+ blocktype, sequence);
- commit:
- jfs_debug(2, "Found transaction %d\n", next_commit_ID);
-
- /* OK, we have a transaction to commit. Rewind to the
- * start of it, gather up all of the buffers in each
- * transaction segment, and replay the segments one by
- * one. */
-
- next_log_block = transaction_start;
+ if (sequence != next_commit_ID) {
+ brelse(bh);
+ break;
+ }
- while (1) {
- int flags;
- char * tagp;
- journal_block_tag_t * tag;
- struct buffer_head * obh;
- struct buffer_head * nbh;
-
- err = jread(&bh, journal, next_log_block++);
- wrap(journal, next_log_block);
- if (err)
- goto failed;
-
- tmp = (journal_header_t *) bh->b_data;
- /* should never happen - we just checked above - AED */
- J_ASSERT(tmp->h_magic == htonl(JFS_MAGIC_NUMBER));
-
- /* If it is the commit block, then we are all done! */
- if (tmp->h_blocktype == htonl(JFS_COMMIT_BLOCK)) {
+ /* OK, we have a valid descriptor block which matches
+ * all of the sequence number checks. What are we going
+ * to do with it? That depends on the pass... */
+
+ switch(blocktype) {
+ case JFS_DESCRIPTOR_BLOCK:
+ /* If it is a valid descriptor block, replay it
+ * in pass REPLAY; otherwise, just skip over the
+ * blocks it describes. */
+ if (pass != PASS_REPLAY) {
+ next_log_block +=
+ count_tags(bh, journal->j_blocksize);
+ wrap(journal, next_log_block);
brelse(bh);
- break;
+ continue;
}
-
+
/* A descriptor block: we can now write all of
* the data blocks. Yay, useful work is finally
* getting done here! */
tagp = &bh->b_data[sizeof(journal_header_t)];
-
while ((tagp - bh->b_data +sizeof(journal_block_tag_t))
<= journal->j_blocksize) {
+ unsigned long io_block;
+
tag = (journal_block_tag_t *) tagp;
flags = ntohl(tag->t_flags);
- err = jread(&obh, journal, next_log_block++);
+ io_block = next_log_block++;
wrap(journal, next_log_block);
+ err = jread(&obh, journal, io_block);
if (err) {
/* Recover what we can, but
* report failure at the end. */
success = err;
printk (KERN_ERR
- "JFS: IO error recovering "
- "block %ld in log\n",
- next_log_block-1);
+ "JBD: IO error %d recovering "
+ "block %lu in log\n",
+ err, io_block);
} else {
- /* can never happen if jread OK - AED */
+ unsigned long blocknr;
+
J_ASSERT(obh != NULL);
-
- /* And find a buffer for the new data
- * being restored */
- nbh = getblk(journal->j_dev,
- ntohl(tag->t_blocknr),
+ blocknr = ntohl(tag->t_blocknr);
+
+ /* If the block has been
+ * revoked, then we're all done
+ * here. */
+ if (journal_test_revoke
+ (journal, blocknr,
+ next_commit_ID)) {
+ brelse(obh);
+ ++info->nr_revoke_hits;
+ goto skip_write;
+ }
+
+ /* Find a buffer for the new
+ * data being restored */
+ nbh = __getblk(journal->j_fs_dev,
+ blocknr,
journal->j_blocksize);
if (nbh == NULL) {
printk(KERN_ERR
- "JFS: Out of memory "
+ "JBD: Out of memory "
"during recovery.\n");
err = -ENOMEM;
brelse(bh);
goto failed;
}
- memcpy(nbh->b_data, obh->b_data,
- journal->j_blocksize);
+ lock_buffer(nbh);
+ memcpy(nbh->b_data, obh->b_data,
+ journal->j_blocksize);
if (flags & JFS_FLAG_ESCAPE) {
- * ((unsigned int *) bh->b_data) = htonl(JFS_MAGIC_NUMBER);
+ *((unsigned int *)bh->b_data) =
+ htonl(JFS_MAGIC_NUMBER);
}
-
- mark_buffer_dirty(nbh, 1);
+
+ BUFFER_TRACE(nbh, "marking dirty");
+ set_buffer_uptodate(nbh);
+ mark_buffer_dirty(nbh);
+ BUFFER_TRACE(nbh, "marking uptodate");
+ ++info->nr_replays;
/* ll_rw_block(WRITE, 1, &nbh); */
+ unlock_buffer(nbh);
brelse(obh);
brelse(nbh);
}
+ skip_write:
tagp += sizeof(journal_block_tag_t);
if (!(flags & JFS_FLAG_SAME_UUID))
tagp += 16;
if (flags & JFS_FLAG_LAST_TAG)
break;
+ }
+
+ brelse(bh);
+ continue;
- } /* end of tag loop */
+ case JFS_COMMIT_BLOCK:
+ /* Found an expected commit block: not much to
+ * do other than move on to the next sequence
+ * number. */
+ brelse(bh);
+ next_commit_ID++;
+ continue;
+ case JFS_REVOKE_BLOCK:
+ /* If we aren't in the REVOKE pass, then we can
+ * just skip over this block. */
+ if (pass != PASS_REVOKE) {
+ brelse(bh);
+ continue;
+ }
+
+ err = scan_revoke_records(journal, bh,
+ next_commit_ID, info);
brelse(bh);
-
- } /* end of descriptor block loop */
-
- /* We have now replayed that entire transaction: start
- * looking for the next transaction. */
- next_commit_ID++;
+ if (err)
+ goto failed;
+ continue;
+
+ default:
+ jbd_debug(3, "Unrecognised magic %d, end of scan.\n",
+ blocktype);
+ brelse(bh);
+ goto done;
+ }
}
-
- finished:
- err = success;
- fsync_dev(journal->j_dev);
- failed:
+ done:
+ /*
+ * We broke out of the log scan loop: either we came to the
+ * known end of the log or we found an unexpected block in the
+ * log. If the latter happened, then we know that the "current"
+ * transaction marks the end of the valid log.
+ */
- /* Restart the log at the next transaction ID, thus invalidating
- * any existing commit records in the log. */
- jfs_debug(0, "JFS: recovery, exit status %d, "
- "recovered transactions %u to %u\n",
- err, first_commit_ID, next_commit_ID);
- journal->j_transaction_sequence = ++next_commit_ID;
+ if (pass == PASS_SCAN)
+ info->end_transaction = next_commit_ID;
+ else {
+ /* It's really bad news if different passes end up at
+ * different places (but possible due to IO errors). */
+ if (info->end_transaction != next_commit_ID) {
+ printk (KERN_ERR "JBD: recovery pass %d ended at "
+ "transaction %u, expected %u\n",
+ pass, next_commit_ID, info->end_transaction);
+ if (!success)
+ success = -EIO;
+ }
+ }
+
+ return success;
+ failed:
return err;
}
+
+
+/* Scan a revoke record, marking all blocks mentioned as revoked. */
+
+static int scan_revoke_records(journal_t *journal, struct buffer_head *bh,
+ tid_t sequence, struct recovery_info *info)
+{
+ journal_revoke_header_t *header;
+ int offset, max;
+
+ header = (journal_revoke_header_t *) bh->b_data;
+ offset = sizeof(journal_revoke_header_t);
+ max = ntohl(header->r_count);
+
+ while (offset < max) {
+ unsigned long blocknr;
+ int err;
+
+ blocknr = ntohl(* ((unsigned int *) (bh->b_data+offset)));
+ offset += 4;
+ err = journal_set_revoke(journal, blocknr, sequence);
+ if (err)
+ return err;
+ ++info->nr_revokes;
+ }
+ return 0;
+}
git://git.whamcloud.com / tools / e2fsprogs.git / blobdiff