diff options
Diffstat (limited to 'fs/jbd2/journal.c')
| -rw-r--r-- | fs/jbd2/journal.c | 361 |
1 files changed, 229 insertions, 132 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index c6d22745553f..1afb701622b0 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -70,7 +70,6 @@ EXPORT_SYMBOL(jbd2_journal_revoke); EXPORT_SYMBOL(jbd2_journal_init_dev); EXPORT_SYMBOL(jbd2_journal_init_inode); -EXPORT_SYMBOL(jbd2_journal_update_format); EXPORT_SYMBOL(jbd2_journal_check_used_features); EXPORT_SYMBOL(jbd2_journal_check_available_features); EXPORT_SYMBOL(jbd2_journal_set_features); @@ -95,7 +94,6 @@ EXPORT_SYMBOL(jbd2_journal_release_jbd_inode); EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate); EXPORT_SYMBOL(jbd2_inode_cache); -static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *); static void __journal_abort_soft (journal_t *journal, int errno); static int jbd2_journal_create_slab(size_t slab_size); @@ -745,6 +743,98 @@ 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); +} + +/* + * This is a variaon of __jbd2_update_log_tail which checks for validity of + * provided log tail and locks j_checkpoint_mutex. So it is safe against races + * with other threads updating log tail. + */ +void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block) +{ + mutex_lock(&journal->j_checkpoint_mutex); + if (tid_gt(tid, journal->j_tail_sequence)) + __jbd2_update_log_tail(journal, tid, block); + mutex_unlock(&journal->j_checkpoint_mutex); +} + struct jbd2_stats_proc_session { journal_t *journal; struct transaction_stats_s *stats; @@ -1113,40 +1203,45 @@ static int journal_reset(journal_t *journal) journal->j_max_transaction_buffers = journal->j_maxlen / 4; - /* Add the dynamic fields and write it to disk. */ - jbd2_journal_update_superblock(journal, 1); - return jbd2_journal_start_thread(journal); -} - -/** - * void jbd2_journal_update_superblock() - Update journal sb on disk. - * @journal: The journal to update. - * @wait: Set to '0' if you don't want to wait for IO completion. - * - * Update a journal's dynamic superblock fields and write it to disk, - * optionally waiting for the IO to complete. - */ -void jbd2_journal_update_superblock(journal_t *journal, int wait) -{ - journal_superblock_t *sb = journal->j_superblock; - struct buffer_head *bh = journal->j_sb_buffer; - /* * As a special case, if the on-disk copy is already marked as needing - * no recovery (s_start == 0) and there are no outstanding transactions - * in the filesystem, then we can safely defer the superblock update - * until the next commit by setting JBD2_FLUSHED. This avoids + * no recovery (s_start == 0), then we can safely defer the superblock + * update until the next commit by setting JBD2_FLUSHED. This avoids * attempting a write to a potential-readonly device. */ - if (sb->s_start == 0 && journal->j_tail_sequence == - journal->j_transaction_sequence) { + if (sb->s_start == 0) { jbd_debug(1, "JBD2: Skipping superblock update on recovered sb " "(start %ld, seq %d, errno %d)\n", journal->j_tail, journal->j_tail_sequence, journal->j_errno); - goto out; + journal->j_flags |= JBD2_FLUSHED; + } else { + /* Lock here to make assertions happy... */ + mutex_lock(&journal->j_checkpoint_mutex); + /* + * 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); + mutex_unlock(&journal->j_checkpoint_mutex); } + return jbd2_journal_start_thread(journal); +} +static void jbd2_write_superblock(journal_t *journal, int write_op) +{ + struct buffer_head *bh = journal->j_sb_buffer; + int ret; + + trace_jbd2_write_superblock(journal, write_op); + 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 @@ -1162,48 +1257,106 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait) clear_buffer_write_io_error(bh); set_buffer_uptodate(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)) { + 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, tid_t tail_tid, + unsigned long tail_block, int write_op) +{ + journal_superblock_t *sb = journal->j_superblock; + + BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); + jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n", + tail_block, tail_tid); + + sb->s_sequence = cpu_to_be32(tail_tid); + sb->s_start = cpu_to_be32(tail_block); + + jbd2_write_superblock(journal, write_op); + + /* Log is no longer empty */ + write_lock(&journal->j_state_lock); + WARN_ON(!sb->s_sequence); + journal->j_flags &= ~JBD2_FLUSHED; + write_unlock(&journal->j_state_lock); +} + +/** + * jbd2_mark_journal_empty() - Mark on disk journal as empty. + * @journal: The journal to update. + * + * Update a journal's dynamic superblock fields to show that journal is empty. + * Write updated superblock to disk waiting for IO to complete. + */ +static void jbd2_mark_journal_empty(journal_t *journal) +{ + journal_superblock_t *sb = journal->j_superblock; + BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); read_lock(&journal->j_state_lock); - jbd_debug(1, "JBD2: updating superblock (start %ld, seq %d, errno %d)\n", - journal->j_tail, journal->j_tail_sequence, journal->j_errno); + jbd_debug(1, "JBD2: Marking journal as empty (seq %d)\n", + journal->j_tail_sequence); sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); - sb->s_start = cpu_to_be32(journal->j_tail); - sb->s_errno = cpu_to_be32(journal->j_errno); + sb->s_start = cpu_to_be32(0); read_unlock(&journal->j_state_lock); - BUFFER_TRACE(bh, "marking dirty"); - mark_buffer_dirty(bh); - if (wait) { - sync_dirty_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); - } - } else - write_dirty_buffer(bh, WRITE); - -out: - /* If we have just flushed the log (by marking s_start==0), then - * any future commit will have to be careful to update the - * superblock again to re-record the true start of the log. */ + jbd2_write_superblock(journal, WRITE_FUA); + /* Log is no longer empty */ write_lock(&journal->j_state_lock); - if (sb->s_start) - journal->j_flags &= ~JBD2_FLUSHED; - else - journal->j_flags |= JBD2_FLUSHED; + journal->j_flags |= JBD2_FLUSHED; write_unlock(&journal->j_state_lock); } + +/** + * jbd2_journal_update_sb_errno() - Update error in the journal. + * @journal: The journal to update. + * + * Update a journal's errno. Write updated superblock to disk waiting for IO + * to complete. + */ +static void jbd2_journal_update_sb_errno(journal_t *journal) +{ + journal_superblock_t *sb = journal->j_superblock; + + read_lock(&journal->j_state_lock); + jbd_debug(1, "JBD2: updating superblock error (errno %d)\n", + journal->j_errno); + sb->s_errno = cpu_to_be32(journal->j_errno); + read_unlock(&journal->j_state_lock); + + jbd2_write_superblock(journal, WRITE_SYNC); +} + /* * Read the superblock for a given journal, performing initial * validation of the format. */ - static int journal_get_superblock(journal_t *journal) { struct buffer_head *bh; @@ -1397,14 +1550,11 @@ int jbd2_journal_destroy(journal_t *journal) if (journal->j_sb_buffer) { if (!is_journal_aborted(journal)) { - /* We can now mark the journal as empty. */ - journal->j_tail = 0; - journal->j_tail_sequence = - ++journal->j_transaction_sequence; - jbd2_journal_update_superblock(journal, 1); - } else { + mutex_lock(&journal->j_checkpoint_mutex); + jbd2_mark_journal_empty(journal); + mutex_unlock(&journal->j_checkpoint_mutex); + } else err = -EIO; - } brelse(journal->j_sb_buffer); } @@ -1551,61 +1701,6 @@ void jbd2_journal_clear_features(journal_t *journal, unsigned long compat, EXPORT_SYMBOL(jbd2_journal_clear_features); /** - * int jbd2_journal_update_format () - Update on-disk journal structure. - * @journal: Journal to act on. - * - * Given an initialised but unloaded journal struct, poke about in the - * on-disk structure to update it to the most recent supported version. - */ -int jbd2_journal_update_format (journal_t *journal) -{ - journal_superblock_t *sb; - int err; - - err = journal_get_superblock(journal); - if (err) - return err; - - sb = journal->j_superblock; - - switch (be32_to_cpu(sb->s_header.h_blocktype)) { - case JBD2_SUPERBLOCK_V2: - return 0; - case JBD2_SUPERBLOCK_V1: - return journal_convert_superblock_v1(journal, sb); - default: - break; - } - return -EINVAL; -} - -static int journal_convert_superblock_v1(journal_t *journal, - journal_superblock_t *sb) -{ - int offset, blocksize; - struct buffer_head *bh; - - printk(KERN_WARNING - "JBD2: Converting superblock from version 1 to 2.\n"); - - /* Pre-initialise new fields to zero */ - offset = ((char *) &(sb->s_feature_compat)) - ((char *) sb); - blocksize = be32_to_cpu(sb->s_blocksize); - memset(&sb->s_feature_compat, 0, blocksize-offset); - - sb->s_nr_users = cpu_to_be32(1); - sb->s_header.h_blocktype = cpu_to_be32(JBD2_SUPERBLOCK_V2); - journal->j_format_version = 2; - - bh = journal->j_sb_buffer; - BUFFER_TRACE(bh, "marking dirty"); - mark_buffer_dirty(bh); - sync_dirty_buffer(bh); - return 0; -} - - -/** * int jbd2_journal_flush () - Flush journal * @journal: Journal to act on. * @@ -1618,7 +1713,6 @@ int jbd2_journal_flush(journal_t *journal) { int err = 0; transaction_t *transaction = NULL; - unsigned long old_tail; write_lock(&journal->j_state_lock); @@ -1653,6 +1747,7 @@ int jbd2_journal_flush(journal_t *journal) if (is_journal_aborted(journal)) return -EIO; + mutex_lock(&journal->j_checkpoint_mutex); jbd2_cleanup_journal_tail(journal); /* Finally, mark the journal as really needing no recovery. @@ -1660,14 +1755,9 @@ int jbd2_journal_flush(journal_t *journal) * the magic code for a fully-recovered superblock. Any future * commits of data to the journal will restore the current * s_start value. */ + jbd2_mark_journal_empty(journal); + mutex_unlock(&journal->j_checkpoint_mutex); write_lock(&journal->j_state_lock); - old_tail = journal->j_tail; - journal->j_tail = 0; - write_unlock(&journal->j_state_lock); - jbd2_journal_update_superblock(journal, 1); - write_lock(&journal->j_state_lock); - journal->j_tail = old_tail; - J_ASSERT(!journal->j_running_transaction); J_ASSERT(!journal->j_committing_transaction); J_ASSERT(!journal->j_checkpoint_transactions); @@ -1707,8 +1797,12 @@ int jbd2_journal_wipe(journal_t *journal, int write) write ? "Clearing" : "Ignoring"); err = jbd2_journal_skip_recovery(journal); - if (write) - jbd2_journal_update_superblock(journal, 1); + if (write) { + /* Lock to make assertions happy... */ + mutex_lock(&journal->j_checkpoint_mutex); + jbd2_mark_journal_empty(journal); + mutex_unlock(&journal->j_checkpoint_mutex); + } no_recovery: return err; @@ -1758,7 +1852,7 @@ static void __journal_abort_soft (journal_t *journal, int errno) __jbd2_journal_abort_hard(journal); if (errno) - jbd2_journal_update_superblock(journal, 1); + jbd2_journal_update_sb_errno(journal); } /** @@ -2016,7 +2110,7 @@ static struct kmem_cache *jbd2_journal_head_cache; static atomic_t nr_journal_heads = ATOMIC_INIT(0); #endif -static int journal_init_jbd2_journal_head_cache(void) +static int jbd2_journal_init_journal_head_cache(void) { int retval; @@ -2034,7 +2128,7 @@ static int journal_init_jbd2_journal_head_cache(void) return retval; } -static void jbd2_journal_destroy_jbd2_journal_head_cache(void) +static void jbd2_journal_destroy_journal_head_cache(void) { if (jbd2_journal_head_cache) { kmem_cache_destroy(jbd2_journal_head_cache); @@ -2322,7 +2416,7 @@ static void __exit jbd2_remove_jbd_stats_proc_entry(void) struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache; -static int __init journal_init_handle_cache(void) +static int __init jbd2_journal_init_handle_cache(void) { jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); if (jbd2_handle_cache == NULL) { @@ -2357,17 +2451,20 @@ static int __init journal_init_caches(void) ret = jbd2_journal_init_revoke_caches(); if (ret == 0) - ret = journal_init_jbd2_journal_head_cache(); + ret = jbd2_journal_init_journal_head_cache(); + if (ret == 0) + ret = jbd2_journal_init_handle_cache(); if (ret == 0) - ret = journal_init_handle_cache(); + ret = jbd2_journal_init_transaction_cache(); return ret; } static void jbd2_journal_destroy_caches(void) { jbd2_journal_destroy_revoke_caches(); - jbd2_journal_destroy_jbd2_journal_head_cache(); + jbd2_journal_destroy_journal_head_cache(); jbd2_journal_destroy_handle_cache(); + jbd2_journal_destroy_transaction_cache(); jbd2_journal_destroy_slabs(); } |