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-rw-r--r--fs/jbd2/journal.c361
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();
}
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