diff options
Diffstat (limited to 'fs/jbd2/recovery.c')
| -rw-r--r-- | fs/jbd2/recovery.c | 950 |
1 files changed, 950 insertions, 0 deletions
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c new file mode 100644 index 0000000000..5b771a3d8d --- /dev/null +++ b/fs/jbd2/recovery.c @@ -0,0 +1,950 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * linux/fs/jbd2/recovery.c + * + * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 + * + * Copyright 1999-2000 Red Hat Software --- All Rights Reserved + * + * Journal recovery routines for the generic filesystem journaling code; + * part of the ext2fs journaling system. + */ + +#ifndef __KERNEL__ +#include "jfs_user.h" +#else +#include <linux/time.h> +#include <linux/fs.h> +#include <linux/jbd2.h> +#include <linux/errno.h> +#include <linux/crc32.h> +#include <linux/blkdev.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; + unsigned long head_block; + + int nr_replays; + int nr_revokes; + int nr_revoke_hits; +}; + +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 journal_brelse_array(struct buffer_head *b[], int n) +{ + while (--n >= 0) + brelse (b[n]); +} + + +/* + * When reading from the journal, we are going through the block device + * layer directly and so there is no readahead being done for us. We + * need to implement any readahead ourselves if we want it to happen at + * all. Recovery is basically one long sequential read, so make sure we + * do the IO in reasonably large chunks. + * + * This is not so critical that we need to be enormously clever about + * the readahead size, though. 128K is a purely arbitrary, good-enough + * fixed value. + */ + +#define MAXBUF 8 +static int do_readahead(journal_t *journal, unsigned int start) +{ + int err; + unsigned int max, nbufs, next; + unsigned long long blocknr; + struct buffer_head *bh; + + struct buffer_head * bufs[MAXBUF]; + + /* Do up to 128K of readahead */ + max = start + (128 * 1024 / journal->j_blocksize); + if (max > journal->j_total_len) + max = journal->j_total_len; + + /* Do the readahead itself. We'll submit MAXBUF buffer_heads at + * a time to the block device IO layer. */ + + nbufs = 0; + + for (next = start; next < max; next++) { + err = jbd2_journal_bmap(journal, next, &blocknr); + + if (err) { + printk(KERN_ERR "JBD2: bad block at offset %u\n", + next); + goto failed; + } + + bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); + if (!bh) { + err = -ENOMEM; + goto failed; + } + + if (!buffer_uptodate(bh) && !buffer_locked(bh)) { + bufs[nbufs++] = bh; + if (nbufs == MAXBUF) { + bh_readahead_batch(nbufs, bufs, 0); + journal_brelse_array(bufs, nbufs); + nbufs = 0; + } + } else + brelse(bh); + } + + if (nbufs) + bh_readahead_batch(nbufs, bufs, 0); + err = 0; + +failed: + if (nbufs) + journal_brelse_array(bufs, nbufs); + return err; +} + +#endif /* __KERNEL__ */ + + +/* + * Read a block from the journal + */ + +static int jread(struct buffer_head **bhp, journal_t *journal, + unsigned int offset) +{ + int err; + unsigned long long blocknr; + struct buffer_head *bh; + + *bhp = NULL; + + if (offset >= journal->j_total_len) { + printk(KERN_ERR "JBD2: corrupted journal superblock\n"); + return -EFSCORRUPTED; + } + + err = jbd2_journal_bmap(journal, offset, &blocknr); + + if (err) { + printk(KERN_ERR "JBD2: bad block at offset %u\n", + offset); + return err; + } + + 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. + */ + bool need_readahead = !buffer_req(bh); + + bh_read_nowait(bh, 0); + if (need_readahead) + do_readahead(journal, offset); + wait_on_buffer(bh); + } + + if (!buffer_uptodate(bh)) { + printk(KERN_ERR "JBD2: Failed to read block at offset %u\n", + offset); + brelse(bh); + return -EIO; + } + + *bhp = bh; + return 0; +} + +static int jbd2_descriptor_block_csum_verify(journal_t *j, void *buf) +{ + struct jbd2_journal_block_tail *tail; + __be32 provided; + __u32 calculated; + + if (!jbd2_journal_has_csum_v2or3(j)) + return 1; + + tail = (struct jbd2_journal_block_tail *)((char *)buf + + j->j_blocksize - sizeof(struct jbd2_journal_block_tail)); + provided = tail->t_checksum; + tail->t_checksum = 0; + calculated = jbd2_chksum(j, j->j_csum_seed, buf, j->j_blocksize); + tail->t_checksum = provided; + + return provided == cpu_to_be32(calculated); +} + +/* + * Count the number of in-use tags in a journal descriptor block. + */ + +static int count_tags(journal_t *journal, struct buffer_head *bh) +{ + char * tagp; + journal_block_tag_t tag; + int nr = 0, size = journal->j_blocksize; + int tag_bytes = journal_tag_bytes(journal); + + if (jbd2_journal_has_csum_v2or3(journal)) + size -= sizeof(struct jbd2_journal_block_tail); + + tagp = &bh->b_data[sizeof(journal_header_t)]; + + while ((tagp - bh->b_data + tag_bytes) <= size) { + memcpy(&tag, tagp, sizeof(tag)); + + nr++; + tagp += tag_bytes; + if (!(tag.t_flags & cpu_to_be16(JBD2_FLAG_SAME_UUID))) + tagp += 16; + + if (tag.t_flags & cpu_to_be16(JBD2_FLAG_LAST_TAG)) + break; + } + + return nr; +} + + +/* Make sure we wrap around the log correctly! */ +#define wrap(journal, var) \ +do { \ + if (var >= (journal)->j_last) \ + var -= ((journal)->j_last - (journal)->j_first); \ +} while (0) + +static int fc_do_one_pass(journal_t *journal, + struct recovery_info *info, enum passtype pass) +{ + unsigned int expected_commit_id = info->end_transaction; + unsigned long next_fc_block; + struct buffer_head *bh; + int err = 0; + + next_fc_block = journal->j_fc_first; + if (!journal->j_fc_replay_callback) + return 0; + + while (next_fc_block <= journal->j_fc_last) { + jbd2_debug(3, "Fast commit replay: next block %ld\n", + next_fc_block); + err = jread(&bh, journal, next_fc_block); + if (err) { + jbd2_debug(3, "Fast commit replay: read error\n"); + break; + } + + err = journal->j_fc_replay_callback(journal, bh, pass, + next_fc_block - journal->j_fc_first, + expected_commit_id); + brelse(bh); + next_fc_block++; + if (err < 0 || err == JBD2_FC_REPLAY_STOP) + break; + err = 0; + } + + if (err) + jbd2_debug(3, "Fast commit replay failed, err = %d\n", err); + + return err; +} + +/** + * jbd2_journal_recover - 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 jbd2_journal_recover(journal_t *journal) +{ + int err, err2; + journal_superblock_t * sb; + + struct recovery_info info; + errseq_t wb_err; + struct address_space *mapping; + + 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) { + jbd2_debug(1, "No recovery required, last transaction %d, head block %u\n", + be32_to_cpu(sb->s_sequence), be32_to_cpu(sb->s_head)); + journal->j_transaction_sequence = be32_to_cpu(sb->s_sequence) + 1; + journal->j_head = be32_to_cpu(sb->s_head); + return 0; + } + + wb_err = 0; + mapping = journal->j_fs_dev->bd_inode->i_mapping; + errseq_check_and_advance(&mapping->wb_err, &wb_err); + 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); + + jbd2_debug(1, "JBD2: recovery, exit status %d, " + "recovered transactions %u to %u\n", + err, info.start_transaction, info.end_transaction); + jbd2_debug(1, "JBD2: 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->j_head = info.head_block; + jbd2_debug(1, "JBD2: last transaction %d, head block %lu\n", + journal->j_transaction_sequence, journal->j_head); + + jbd2_journal_clear_revoke(journal); + err2 = sync_blockdev(journal->j_fs_dev); + if (!err) + err = err2; + err2 = errseq_check_and_advance(&mapping->wb_err, &wb_err); + if (!err) + err = err2; + /* Make sure all replayed data is on permanent storage */ + if (journal->j_flags & JBD2_BARRIER) { + err2 = blkdev_issue_flush(journal->j_fs_dev); + if (!err) + err = err2; + } + return err; +} + +/** + * jbd2_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 doesn't appear to be exported.. + * + * 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 jbd2_journal_skip_recovery(journal_t *journal) +{ + int err; + + struct recovery_info info; + + memset (&info, 0, sizeof(info)); + + err = do_one_pass(journal, &info, PASS_SCAN); + + if (err) { + printk(KERN_ERR "JBD2: error %d scanning journal\n", err); + ++journal->j_transaction_sequence; + journal->j_head = journal->j_first; + } else { +#ifdef CONFIG_JBD2_DEBUG + int dropped = info.end_transaction - + be32_to_cpu(journal->j_superblock->s_sequence); + jbd2_debug(1, + "JBD2: ignoring %d transaction%s from the journal.\n", + dropped, (dropped == 1) ? "" : "s"); +#endif + journal->j_transaction_sequence = ++info.end_transaction; + journal->j_head = info.head_block; + } + + journal->j_tail = 0; + return err; +} + +static inline unsigned long long read_tag_block(journal_t *journal, + journal_block_tag_t *tag) +{ + unsigned long long block = be32_to_cpu(tag->t_blocknr); + if (jbd2_has_feature_64bit(journal)) + block |= (u64)be32_to_cpu(tag->t_blocknr_high) << 32; + return block; +} + +/* + * calc_chksums calculates the checksums for the blocks described in the + * descriptor block. + */ +static int calc_chksums(journal_t *journal, struct buffer_head *bh, + unsigned long *next_log_block, __u32 *crc32_sum) +{ + int i, num_blks, err; + unsigned long io_block; + struct buffer_head *obh; + + num_blks = count_tags(journal, bh); + /* Calculate checksum of the descriptor block. */ + *crc32_sum = crc32_be(*crc32_sum, (void *)bh->b_data, bh->b_size); + + for (i = 0; i < num_blks; i++) { + io_block = (*next_log_block)++; + wrap(journal, *next_log_block); + err = jread(&obh, journal, io_block); + if (err) { + printk(KERN_ERR "JBD2: IO error %d recovering block " + "%lu in log\n", err, io_block); + return 1; + } else { + *crc32_sum = crc32_be(*crc32_sum, (void *)obh->b_data, + obh->b_size); + } + put_bh(obh); + } + return 0; +} + +static int jbd2_commit_block_csum_verify(journal_t *j, void *buf) +{ + struct commit_header *h; + __be32 provided; + __u32 calculated; + + if (!jbd2_journal_has_csum_v2or3(j)) + return 1; + + h = buf; + provided = h->h_chksum[0]; + h->h_chksum[0] = 0; + calculated = jbd2_chksum(j, j->j_csum_seed, buf, j->j_blocksize); + h->h_chksum[0] = provided; + + return provided == cpu_to_be32(calculated); +} + +static int jbd2_block_tag_csum_verify(journal_t *j, journal_block_tag_t *tag, + journal_block_tag3_t *tag3, + void *buf, __u32 sequence) +{ + __u32 csum32; + __be32 seq; + + if (!jbd2_journal_has_csum_v2or3(j)) + return 1; + + seq = cpu_to_be32(sequence); + csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&seq, sizeof(seq)); + csum32 = jbd2_chksum(j, csum32, buf, j->j_blocksize); + + if (jbd2_has_feature_csum3(j)) + return tag3->t_checksum == cpu_to_be32(csum32); + else + return tag->t_checksum == cpu_to_be16(csum32); +} + +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, head_block; + int err, success = 0; + journal_superblock_t * sb; + journal_header_t * tmp; + struct buffer_head * bh; + unsigned int sequence; + int blocktype; + int tag_bytes = journal_tag_bytes(journal); + __u32 crc32_sum = ~0; /* Transactional Checksums */ + int descr_csum_size = 0; + int block_error = 0; + bool need_check_commit_time = false; + __u64 last_trans_commit_time = 0, commit_time; + + /* + * First thing is to establish what we expect to find in the log + * (in terms of transaction IDs), and where (in terms of log + * block offsets): query the superblock. + */ + + sb = journal->j_superblock; + next_commit_ID = be32_to_cpu(sb->s_sequence); + next_log_block = be32_to_cpu(sb->s_start); + head_block = next_log_block; + + first_commit_ID = next_commit_ID; + if (pass == PASS_SCAN) + info->start_transaction = first_commit_ID; + + jbd2_debug(1, "Starting recovery pass %d\n", pass); + + /* + * Now we walk through the log, transaction by transaction, + * making sure that each transaction has a commit block in the + * expected place. Each complete transaction gets replayed back + * into the main filesystem. + */ + + while (1) { + int flags; + char * tagp; + journal_block_tag_t tag; + struct buffer_head * obh; + struct buffer_head * nbh; + + cond_resched(); + + /* 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; + + jbd2_debug(2, "Scanning for sequence ID %u at %lu/%lu\n", + next_commit_ID, next_log_block, journal->j_last); + + /* Skip over each chunk of the transaction looking + * either the next descriptor block or the final commit + * record. */ + + jbd2_debug(3, "JBD2: checking block %ld\n", next_log_block); + err = jread(&bh, journal, next_log_block); + if (err) + goto failed; + + next_log_block++; + wrap(journal, next_log_block); + + /* 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. */ + + tmp = (journal_header_t *)bh->b_data; + + if (tmp->h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER)) { + brelse(bh); + break; + } + + blocktype = be32_to_cpu(tmp->h_blocktype); + sequence = be32_to_cpu(tmp->h_sequence); + jbd2_debug(3, "Found magic %d, sequence %d\n", + blocktype, sequence); + + if (sequence != next_commit_ID) { + brelse(bh); + break; + } + + /* 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 JBD2_DESCRIPTOR_BLOCK: + /* Verify checksum first */ + if (jbd2_journal_has_csum_v2or3(journal)) + descr_csum_size = + sizeof(struct jbd2_journal_block_tail); + if (descr_csum_size > 0 && + !jbd2_descriptor_block_csum_verify(journal, + bh->b_data)) { + /* + * PASS_SCAN can see stale blocks due to lazy + * journal init. Don't error out on those yet. + */ + if (pass != PASS_SCAN) { + pr_err("JBD2: Invalid checksum recovering block %lu in log\n", + next_log_block); + err = -EFSBADCRC; + brelse(bh); + goto failed; + } + need_check_commit_time = true; + jbd2_debug(1, + "invalid descriptor block found in %lu\n", + next_log_block); + } + + /* If it is a valid descriptor block, replay it + * in pass REPLAY; if journal_checksums enabled, then + * calculate checksums in PASS_SCAN, otherwise, + * just skip over the blocks it describes. */ + if (pass != PASS_REPLAY) { + if (pass == PASS_SCAN && + jbd2_has_feature_checksum(journal) && + !need_check_commit_time && + !info->end_transaction) { + if (calc_chksums(journal, bh, + &next_log_block, + &crc32_sum)) { + put_bh(bh); + break; + } + put_bh(bh); + continue; + } + next_log_block += count_tags(journal, bh); + wrap(journal, next_log_block); + put_bh(bh); + 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 + tag_bytes) + <= journal->j_blocksize - descr_csum_size) { + unsigned long io_block; + + memcpy(&tag, tagp, sizeof(tag)); + flags = be16_to_cpu(tag.t_flags); + + 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 + "JBD2: IO error %d recovering " + "block %ld in log\n", + err, io_block); + } else { + unsigned long long blocknr; + + J_ASSERT(obh != NULL); + blocknr = read_tag_block(journal, + &tag); + + /* If the block has been + * revoked, then we're all done + * here. */ + if (jbd2_journal_test_revoke + (journal, blocknr, + next_commit_ID)) { + brelse(obh); + ++info->nr_revoke_hits; + goto skip_write; + } + + /* Look for block corruption */ + if (!jbd2_block_tag_csum_verify( + journal, &tag, (journal_block_tag3_t *)tagp, + obh->b_data, be32_to_cpu(tmp->h_sequence))) { + brelse(obh); + success = -EFSBADCRC; + printk(KERN_ERR "JBD2: Invalid " + "checksum recovering " + "data block %llu in " + "log\n", blocknr); + block_error = 1; + 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 + "JBD2: Out of memory " + "during recovery.\n"); + err = -ENOMEM; + brelse(bh); + brelse(obh); + goto failed; + } + + lock_buffer(nbh); + memcpy(nbh->b_data, obh->b_data, + journal->j_blocksize); + if (flags & JBD2_FLAG_ESCAPE) { + *((__be32 *)nbh->b_data) = + cpu_to_be32(JBD2_MAGIC_NUMBER); + } + + BUFFER_TRACE(nbh, "marking dirty"); + set_buffer_uptodate(nbh); + mark_buffer_dirty(nbh); + BUFFER_TRACE(nbh, "marking uptodate"); + ++info->nr_replays; + unlock_buffer(nbh); + brelse(obh); + brelse(nbh); + } + + skip_write: + tagp += tag_bytes; + if (!(flags & JBD2_FLAG_SAME_UUID)) + tagp += 16; + + if (flags & JBD2_FLAG_LAST_TAG) + break; + } + + brelse(bh); + continue; + + case JBD2_COMMIT_BLOCK: + /* How to differentiate between interrupted commit + * and journal corruption ? + * + * {nth transaction} + * Checksum Verification Failed + * | + * ____________________ + * | | + * async_commit sync_commit + * | | + * | GO TO NEXT "Journal Corruption" + * | TRANSACTION + * | + * {(n+1)th transanction} + * | + * _______|______________ + * | | + * Commit block found Commit block not found + * | | + * "Journal Corruption" | + * _____________|_________ + * | | + * nth trans corrupt OR nth trans + * and (n+1)th interrupted interrupted + * before commit block + * could reach the disk. + * (Cannot find the difference in above + * mentioned conditions. Hence assume + * "Interrupted Commit".) + */ + commit_time = be64_to_cpu( + ((struct commit_header *)bh->b_data)->h_commit_sec); + /* + * If need_check_commit_time is set, it means we are in + * PASS_SCAN and csum verify failed before. If + * commit_time is increasing, it's the same journal, + * otherwise it is stale journal block, just end this + * recovery. + */ + if (need_check_commit_time) { + if (commit_time >= last_trans_commit_time) { + pr_err("JBD2: Invalid checksum found in transaction %u\n", + next_commit_ID); + err = -EFSBADCRC; + brelse(bh); + goto failed; + } + ignore_crc_mismatch: + /* + * It likely does not belong to same journal, + * just end this recovery with success. + */ + jbd2_debug(1, "JBD2: Invalid checksum ignored in transaction %u, likely stale data\n", + next_commit_ID); + brelse(bh); + goto done; + } + + /* + * Found an expected commit block: if checksums + * are present, verify them in PASS_SCAN; else not + * much to do other than move on to the next sequence + * number. + */ + if (pass == PASS_SCAN && + jbd2_has_feature_checksum(journal)) { + struct commit_header *cbh = + (struct commit_header *)bh->b_data; + unsigned found_chksum = + be32_to_cpu(cbh->h_chksum[0]); + + if (info->end_transaction) { + journal->j_failed_commit = + info->end_transaction; + brelse(bh); + break; + } + + /* Neither checksum match nor unused? */ + if (!((crc32_sum == found_chksum && + cbh->h_chksum_type == + JBD2_CRC32_CHKSUM && + cbh->h_chksum_size == + JBD2_CRC32_CHKSUM_SIZE) || + (cbh->h_chksum_type == 0 && + cbh->h_chksum_size == 0 && + found_chksum == 0))) + goto chksum_error; + + crc32_sum = ~0; + } + if (pass == PASS_SCAN && + !jbd2_commit_block_csum_verify(journal, + bh->b_data)) { + chksum_error: + if (commit_time < last_trans_commit_time) + goto ignore_crc_mismatch; + info->end_transaction = next_commit_ID; + info->head_block = head_block; + + if (!jbd2_has_feature_async_commit(journal)) { + journal->j_failed_commit = + next_commit_ID; + brelse(bh); + break; + } + } + if (pass == PASS_SCAN) { + last_trans_commit_time = commit_time; + head_block = next_log_block; + } + brelse(bh); + next_commit_ID++; + continue; + + case JBD2_REVOKE_BLOCK: + /* + * Check revoke block crc in pass_scan, if csum verify + * failed, check commit block time later. + */ + if (pass == PASS_SCAN && + !jbd2_descriptor_block_csum_verify(journal, + bh->b_data)) { + jbd2_debug(1, "JBD2: invalid revoke block found in %lu\n", + next_log_block); + need_check_commit_time = true; + } + /* 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); + if (err) + goto failed; + continue; + + default: + jbd2_debug(3, "Unrecognised magic %d, end of scan.\n", + blocktype); + brelse(bh); + goto done; + } + } + + 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. + */ + + if (pass == PASS_SCAN) { + if (!info->end_transaction) + info->end_transaction = next_commit_ID; + if (!info->head_block) + info->head_block = head_block; + } 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 "JBD2: recovery pass %d ended at " + "transaction %u, expected %u\n", + pass, next_commit_ID, info->end_transaction); + if (!success) + success = -EIO; + } + } + + if (jbd2_has_feature_fast_commit(journal) && pass != PASS_REVOKE) { + err = fc_do_one_pass(journal, info, pass); + if (err) + success = err; + } + + if (block_error && success == 0) + 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) +{ + jbd2_journal_revoke_header_t *header; + int offset, max; + unsigned csum_size = 0; + __u32 rcount; + int record_len = 4; + + header = (jbd2_journal_revoke_header_t *) bh->b_data; + offset = sizeof(jbd2_journal_revoke_header_t); + rcount = be32_to_cpu(header->r_count); + + if (jbd2_journal_has_csum_v2or3(journal)) + csum_size = sizeof(struct jbd2_journal_block_tail); + if (rcount > journal->j_blocksize - csum_size) + return -EINVAL; + max = rcount; + + if (jbd2_has_feature_64bit(journal)) + record_len = 8; + + while (offset + record_len <= max) { + unsigned long long blocknr; + int err; + + if (record_len == 4) + blocknr = be32_to_cpu(* ((__be32 *) (bh->b_data+offset))); + else + blocknr = be64_to_cpu(* ((__be64 *) (bh->b_data+offset))); + offset += record_len; + err = jbd2_journal_set_revoke(journal, blocknr, sequence); + if (err) + return err; + ++info->nr_revokes; + } + return 0; +} |