diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/jbd2/checkpoint.c | 75 | ||||
| -rw-r--r-- | fs/jbd2/commit.c | 11 | ||||
| -rw-r--r-- | fs/jbd2/journal.c | 136 | ||||
| -rw-r--r-- | fs/jbd2/recovery.c | 5 |
4 files changed, 142 insertions, 85 deletions
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index aa09868..de76f1f 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -478,79 +478,28 @@ out: int jbd2_cleanup_journal_tail(journal_t *journal) { - transaction_t * transaction; tid_t first_tid; - unsigned long blocknr, freed; + unsigned long blocknr; if (is_journal_aborted(journal)) return 1; - /* OK, work out the oldest transaction remaining in the log, and - * the log block it starts at. - * - * If the log is now empty, we need to work out which is the - * next transaction ID we will write, and where it will - * start. */ - - write_lock(&journal->j_state_lock); - spin_lock(&journal->j_list_lock); - transaction = journal->j_checkpoint_transactions; - if (transaction) { - first_tid = transaction->t_tid; - blocknr = transaction->t_log_start; - } else if ((transaction = journal->j_committing_transaction) != NULL) { - first_tid = transaction->t_tid; - blocknr = transaction->t_log_start; - } else if ((transaction = journal->j_running_transaction) != NULL) { - first_tid = transaction->t_tid; - blocknr = journal->j_head; - } else { - first_tid = journal->j_transaction_sequence; - blocknr = journal->j_head; - } - spin_unlock(&journal->j_list_lock); - J_ASSERT(blocknr != 0); - - /* If the oldest pinned transaction is at the tail of the log - already then there's not much we can do right now. */ - if (journal->j_tail_sequence == first_tid) { - write_unlock(&journal->j_state_lock); + if (!jbd2_journal_get_log_tail(journal, &first_tid, &blocknr)) return 1; - } - - /* OK, update the superblock to recover the freed space. - * Physical blocks come first: have we wrapped beyond the end of - * the log? */ - freed = blocknr - journal->j_tail; - if (blocknr < journal->j_tail) - freed = freed + journal->j_last - journal->j_first; - - trace_jbd2_cleanup_journal_tail(journal, first_tid, blocknr, freed); - jbd_debug(1, - "Cleaning journal tail from %d to %d (offset %lu), " - "freeing %lu\n", - journal->j_tail_sequence, first_tid, blocknr, freed); - - journal->j_free += freed; - journal->j_tail_sequence = first_tid; - journal->j_tail = blocknr; - write_unlock(&journal->j_state_lock); + J_ASSERT(blocknr != 0); /* - * If there is an external journal, we need to make sure that - * any data blocks that were recently written out --- perhaps - * by jbd2_log_do_checkpoint() --- are flushed out before we - * drop the transactions from the external journal. It's - * unlikely this will be necessary, especially with a - * appropriately sized journal, but we need this to guarantee - * correctness. Fortunately jbd2_cleanup_journal_tail() - * doesn't get called all that often. + * We need to make sure that any blocks that were recently written out + * --- perhaps by jbd2_log_do_checkpoint() --- are flushed out before + * we drop the transactions from the journal. It's unlikely this will + * be necessary, especially with an appropriately sized journal, but we + * need this to guarantee correctness. Fortunately + * jbd2_cleanup_journal_tail() doesn't get called all that often. */ - if ((journal->j_fs_dev != journal->j_dev) && - (journal->j_flags & JBD2_BARRIER)) + if (journal->j_flags & JBD2_BARRIER) blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL, NULL); - if (!(journal->j_flags & JBD2_ABORT)) - jbd2_journal_update_sb_log_tail(journal); + + __jbd2_update_log_tail(journal, first_tid, blocknr); return 0; } diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index aba8dbd..bccb605 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -340,7 +340,16 @@ void jbd2_journal_commit_transaction(journal_t *journal) /* Do we need to erase the effects of a prior jbd2_journal_flush? */ if (journal->j_flags & JBD2_FLUSHED) { jbd_debug(3, "super block updated\n"); - jbd2_journal_update_sb_log_tail(journal); + /* + * We hold j_checkpoint_mutex so tail cannot change under us. + * We don't need any special data guarantees for writing sb + * since journal is empty and it is ok for write to be + * flushed only with transaction commit. + */ + jbd2_journal_update_sb_log_tail(journal, + journal->j_tail_sequence, + journal->j_tail, + WRITE_SYNC); } else { jbd_debug(3, "superblock not updated\n"); } diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index e305409..55e9881 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -775,6 +775,85 @@ struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) return jbd2_journal_add_journal_head(bh); } +/* + * Return tid of the oldest transaction in the journal and block in the journal + * where the transaction starts. + * + * If the journal is now empty, return which will be the next transaction ID + * we will write and where will that transaction start. + * + * The return value is 0 if journal tail cannot be pushed any further, 1 if + * it can. + */ +int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, + unsigned long *block) +{ + transaction_t *transaction; + int ret; + + read_lock(&journal->j_state_lock); + spin_lock(&journal->j_list_lock); + transaction = journal->j_checkpoint_transactions; + if (transaction) { + *tid = transaction->t_tid; + *block = transaction->t_log_start; + } else if ((transaction = journal->j_committing_transaction) != NULL) { + *tid = transaction->t_tid; + *block = transaction->t_log_start; + } else if ((transaction = journal->j_running_transaction) != NULL) { + *tid = transaction->t_tid; + *block = journal->j_head; + } else { + *tid = journal->j_transaction_sequence; + *block = journal->j_head; + } + ret = tid_gt(*tid, journal->j_tail_sequence); + spin_unlock(&journal->j_list_lock); + read_unlock(&journal->j_state_lock); + + return ret; +} + +/* + * Update information in journal structure and in on disk journal superblock + * about log tail. This function does not check whether information passed in + * really pushes log tail further. It's responsibility of the caller to make + * sure provided log tail information is valid (e.g. by holding + * j_checkpoint_mutex all the time between computing log tail and calling this + * function as is the case with jbd2_cleanup_journal_tail()). + * + * Requires j_checkpoint_mutex + */ +void __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block) +{ + unsigned long freed; + + BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); + + /* + * We cannot afford for write to remain in drive's caches since as + * soon as we update j_tail, next transaction can start reusing journal + * space and if we lose sb update during power failure we'd replay + * old transaction with possibly newly overwritten data. + */ + jbd2_journal_update_sb_log_tail(journal, tid, block, WRITE_FUA); + write_lock(&journal->j_state_lock); + freed = block - journal->j_tail; + if (block < journal->j_tail) + freed += journal->j_last - journal->j_first; + + trace_jbd2_update_log_tail(journal, tid, block, freed); + jbd_debug(1, + "Cleaning journal tail from %d to %d (offset %lu), " + "freeing %lu\n", + journal->j_tail_sequence, tid, block, freed); + + journal->j_free += freed; + journal->j_tail_sequence = tid; + journal->j_tail = block; + write_unlock(&journal->j_state_lock); +} + struct jbd2_stats_proc_session { journal_t *journal; struct transaction_stats_s *stats; @@ -1156,16 +1235,28 @@ static int journal_reset(journal_t *journal) journal->j_errno); journal->j_flags |= JBD2_FLUSHED; } else { - /* Add the dynamic fields and write it to disk. */ - jbd2_journal_update_sb_log_tail(journal); + /* + * Update log tail information. We use WRITE_FUA since new + * transaction will start reusing journal space and so we + * must make sure information about current log tail is on + * disk before that. + */ + jbd2_journal_update_sb_log_tail(journal, + journal->j_tail_sequence, + journal->j_tail, + WRITE_FUA); } return jbd2_journal_start_thread(journal); } -static void jbd2_write_superblock(journal_t *journal) +static void jbd2_write_superblock(journal_t *journal, int write_op) { struct buffer_head *bh = journal->j_sb_buffer; + int ret; + if (!(journal->j_flags & JBD2_BARRIER)) + write_op &= ~(REQ_FUA | REQ_FLUSH); + lock_buffer(bh); if (buffer_write_io_error(bh)) { /* * Oh, dear. A previous attempt to write the journal @@ -1181,39 +1272,44 @@ static void jbd2_write_superblock(journal_t *journal) clear_buffer_write_io_error(bh); set_buffer_uptodate(bh); } - - BUFFER_TRACE(bh, "marking dirty"); - mark_buffer_dirty(bh); - sync_dirty_buffer(bh); + get_bh(bh); + bh->b_end_io = end_buffer_write_sync; + ret = submit_bh(write_op, bh); + wait_on_buffer(bh); if (buffer_write_io_error(bh)) { - printk(KERN_ERR "JBD2: I/O error detected " - "when updating journal superblock for %s.\n", - journal->j_devname); clear_buffer_write_io_error(bh); set_buffer_uptodate(bh); + ret = -EIO; + } + if (ret) { + printk(KERN_ERR "JBD2: Error %d detected when updating " + "journal superblock for %s.\n", ret, + journal->j_devname); } } /** * jbd2_journal_update_sb_log_tail() - Update log tail in journal sb on disk. * @journal: The journal to update. + * @tail_tid: TID of the new transaction at the tail of the log + * @tail_block: The first block of the transaction at the tail of the log + * @write_op: With which operation should we write the journal sb * * Update a journal's superblock information about log tail and write it to * disk, waiting for the IO to complete. */ -void jbd2_journal_update_sb_log_tail(journal_t *journal) +void jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid, + unsigned long tail_block, int write_op) { journal_superblock_t *sb = journal->j_superblock; - read_lock(&journal->j_state_lock); - jbd_debug(1, "JBD2: updating superblock (start %ld, seq %d)\n", - journal->j_tail, journal->j_tail_sequence); + jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n", + tail_block, tail_tid); - sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); - sb->s_start = cpu_to_be32(journal->j_tail); - read_unlock(&journal->j_state_lock); + sb->s_sequence = cpu_to_be32(tail_tid); + sb->s_start = cpu_to_be32(tail_block); - jbd2_write_superblock(journal); + jbd2_write_superblock(journal, write_op); /* Log is no longer empty */ write_lock(&journal->j_state_lock); WARN_ON(!sb->s_sequence); @@ -1240,7 +1336,7 @@ static void jbd2_mark_journal_empty(journal_t *journal) sb->s_start = cpu_to_be32(0); read_unlock(&journal->j_state_lock); - jbd2_write_superblock(journal); + jbd2_write_superblock(journal, WRITE_FUA); /* Log is no longer empty */ write_lock(&journal->j_state_lock); @@ -1266,7 +1362,7 @@ static void jbd2_journal_update_sb_errno(journal_t *journal) sb->s_errno = cpu_to_be32(journal->j_errno); read_unlock(&journal->j_state_lock); - jbd2_write_superblock(journal); + jbd2_write_superblock(journal, WRITE_SYNC); } /* diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index 421834b..875df5f 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -21,6 +21,7 @@ #include <linux/jbd2.h> #include <linux/errno.h> #include <linux/crc32.h> +#include <linux/blkdev.h> #endif /* @@ -265,7 +266,9 @@ int jbd2_journal_recover(journal_t *journal) err2 = sync_blockdev(journal->j_fs_dev); if (!err) err = err2; - + /* Make sure all replayed data is on permanent storage */ + if (journal->j_flags & JBD2_BARRIER) + blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL, NULL); return err; } |