#include <linux/module.h>
static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh);
+static void __jbd2_journal_unfile_buffer(struct journal_head *jh);
/*
* jbd2_get_transaction: obtain a new transaction_t object.
*/
/*
- * Update transiaction's maximum wait time, if debugging is enabled.
+ * Update transaction's maximum wait time, if debugging is enabled.
*
* In order for t_max_wait to be reliable, it must be protected by a
* lock. But doing so will mean that start_this_handle() can not be
* means that maximum wait time reported by the jbd2_run_stats
* tracepoint will always be zero.
*/
-static inline void update_t_max_wait(transaction_t *transaction)
+static inline void update_t_max_wait(transaction_t *transaction,
+ unsigned long ts)
{
#ifdef CONFIG_JBD2_DEBUG
- unsigned long ts = jiffies;
-
if (jbd2_journal_enable_debug &&
time_after(transaction->t_start, ts)) {
ts = jbd2_time_diff(ts, transaction->t_start);
static int start_this_handle(journal_t *journal, handle_t *handle,
int gfp_mask)
{
- transaction_t *transaction;
- int needed;
- int nblocks = handle->h_buffer_credits;
- transaction_t *new_transaction = NULL;
+ transaction_t *transaction, *new_transaction = NULL;
+ tid_t tid;
+ int needed, need_to_start;
+ int nblocks = handle->h_buffer_credits;
+ unsigned long ts = jiffies;
if (nblocks > journal->j_max_transaction_buffers) {
printk(KERN_ERR "JBD: %s wants too many credits (%d > %d)\n",
*/
repeat:
read_lock(&journal->j_state_lock);
+ BUG_ON(journal->j_flags & JBD2_UNMOUNT);
if (is_journal_aborted(journal) ||
(journal->j_errno != 0 && !(journal->j_flags & JBD2_ACK_ERR))) {
read_unlock(&journal->j_state_lock);
atomic_sub(nblocks, &transaction->t_outstanding_credits);
prepare_to_wait(&journal->j_wait_transaction_locked, &wait,
TASK_UNINTERRUPTIBLE);
- __jbd2_log_start_commit(journal, transaction->t_tid);
+ tid = transaction->t_tid;
+ need_to_start = !tid_geq(journal->j_commit_request, tid);
read_unlock(&journal->j_state_lock);
+ if (need_to_start)
+ jbd2_log_start_commit(journal, tid);
schedule();
finish_wait(&journal->j_wait_transaction_locked, &wait);
goto repeat;
* the committing transaction. Really, we only need to give it
* committing_transaction->t_outstanding_credits plus "enough" for
* the log control blocks.
- * Also, this test is inconsitent with the matching one in
+ * Also, this test is inconsistent with the matching one in
* jbd2_journal_extend().
*/
if (__jbd2_log_space_left(journal) < jbd_space_needed(journal)) {
/* OK, account for the buffers that this operation expects to
* use and add the handle to the running transaction.
*/
- update_t_max_wait(transaction);
+ update_t_max_wait(transaction, ts);
handle->h_transaction = transaction;
atomic_inc(&transaction->t_updates);
atomic_inc(&transaction->t_handle_count);
* This function is visible to journal users (like ext3fs), so is not
* called with the journal already locked.
*
- * Return a pointer to a newly allocated handle, or NULL on failure
+ * Return a pointer to a newly allocated handle, or an ERR_PTR() value
+ * on failure.
*/
handle_t *jbd2__journal_start(journal_t *journal, int nblocks, int gfp_mask)
{
jbd2_free_handle(handle);
current->journal_info = NULL;
handle = ERR_PTR(err);
- goto out;
}
-out:
return handle;
}
EXPORT_SYMBOL(jbd2__journal_start);
{
transaction_t *transaction = handle->h_transaction;
journal_t *journal = transaction->t_journal;
- int ret;
+ tid_t tid;
+ int need_to_start, ret;
/* If we've had an abort of any type, don't even think about
* actually doing the restart! */
spin_unlock(&transaction->t_handle_lock);
jbd_debug(2, "restarting handle %p\n", handle);
- __jbd2_log_start_commit(journal, transaction->t_tid);
+ tid = transaction->t_tid;
+ need_to_start = !tid_geq(journal->j_commit_request, tid);
read_unlock(&journal->j_state_lock);
+ if (need_to_start)
+ jbd2_log_start_commit(journal, tid);
lock_map_release(&handle->h_lockdep_map);
handle->h_buffer_credits = nblocks;
transaction = handle->h_transaction;
journal = transaction->t_journal;
- jbd_debug(5, "buffer_head %p, force_copy %d\n", jh, force_copy);
+ jbd_debug(5, "journal_head %p, force_copy %d\n", jh, force_copy);
JBUFFER_TRACE(jh, "entry");
repeat:
if (!jh->b_transaction) {
JBUFFER_TRACE(jh, "no transaction");
J_ASSERT_JH(jh, !jh->b_next_transaction);
- jh->b_transaction = transaction;
JBUFFER_TRACE(jh, "file as BJ_Reserved");
spin_lock(&journal->j_list_lock);
__jbd2_journal_file_buffer(jh, transaction, BJ_Reserved);
J_EXPECT_JH(jh, buffer_uptodate(jh2bh(jh)),
"Possible IO failure.\n");
page = jh2bh(jh)->b_page;
- offset = ((unsigned long) jh2bh(jh)->b_data) & ~PAGE_MASK;
+ offset = offset_in_page(jh2bh(jh)->b_data);
source = kmap_atomic(page, KM_USER0);
/* Fire data frozen trigger just before we copy the data */
jbd2_buffer_frozen_trigger(jh, source + offset,
* int jbd2_journal_get_write_access() - notify intent to modify a buffer for metadata (not data) update.
* @handle: transaction to add buffer modifications to
* @bh: bh to be used for metadata writes
- * @credits: variable that will receive credits for the buffer
*
* Returns an error code or 0 on success.
*
* committed and so it's safe to clear the dirty bit.
*/
clear_buffer_dirty(jh2bh(jh));
- jh->b_transaction = transaction;
-
/* first access by this transaction */
jh->b_modified = 0;
*/
JBUFFER_TRACE(jh, "cancelling revoke");
jbd2_journal_cancel_revoke(handle, jh);
- jbd2_journal_put_journal_head(jh);
out:
+ jbd2_journal_put_journal_head(jh);
return err;
}
* non-rewindable consequences
* @handle: transaction
* @bh: buffer to undo
- * @credits: store the number of taken credits here (if not NULL)
*
* Sometimes there is a need to distinguish between metadata which has
* been committed to disk and that which has not. The ext3fs code uses
__jbd2_journal_file_buffer(jh, transaction, BJ_Forget);
} else {
__jbd2_journal_unfile_buffer(jh);
- jbd2_journal_remove_journal_head(bh);
- __brelse(bh);
if (!buffer_jbd(bh)) {
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
/*
* Once we drop t_updates, if it goes to zero the transaction
- * could start commiting on us and eventually disappear. So
+ * could start committing on us and eventually disappear. So
* once we do this, we must not dereference transaction
* pointer again.
*/
mark_buffer_dirty(bh); /* Expose it to the VM */
}
-void __jbd2_journal_unfile_buffer(struct journal_head *jh)
+/*
+ * Remove buffer from all transactions.
+ *
+ * Called with bh_state lock and j_list_lock
+ *
+ * jh and bh may be already freed when this function returns.
+ */
+static void __jbd2_journal_unfile_buffer(struct journal_head *jh)
{
__jbd2_journal_temp_unlink_buffer(jh);
jh->b_transaction = NULL;
+ jbd2_journal_put_journal_head(jh);
}
void jbd2_journal_unfile_buffer(journal_t *journal, struct journal_head *jh)
{
- jbd_lock_bh_state(jh2bh(jh));
+ struct buffer_head *bh = jh2bh(jh);
+
+ /* Get reference so that buffer cannot be freed before we unlock it */
+ get_bh(bh);
+ jbd_lock_bh_state(bh);
spin_lock(&journal->j_list_lock);
__jbd2_journal_unfile_buffer(jh);
spin_unlock(&journal->j_list_lock);
- jbd_unlock_bh_state(jh2bh(jh));
+ jbd_unlock_bh_state(bh);
+ __brelse(bh);
}
/*
if (jh->b_jlist == BJ_None) {
JBUFFER_TRACE(jh, "remove from checkpoint list");
__jbd2_journal_remove_checkpoint(jh);
- jbd2_journal_remove_journal_head(bh);
- __brelse(bh);
}
}
spin_unlock(&journal->j_list_lock);
/*
* We take our own ref against the journal_head here to avoid
* having to add tons of locking around each instance of
- * jbd2_journal_remove_journal_head() and
* jbd2_journal_put_journal_head().
*/
jh = jbd2_journal_grab_journal_head(bh);
int may_free = 1;
struct buffer_head *bh = jh2bh(jh);
- __jbd2_journal_unfile_buffer(jh);
-
if (jh->b_cp_transaction) {
JBUFFER_TRACE(jh, "on running+cp transaction");
+ __jbd2_journal_temp_unlink_buffer(jh);
/*
* We don't want to write the buffer anymore, clear the
* bit so that we don't confuse checks in
may_free = 0;
} else {
JBUFFER_TRACE(jh, "on running transaction");
- jbd2_journal_remove_journal_head(bh);
- __brelse(bh);
+ __jbd2_journal_unfile_buffer(jh);
}
return may_free;
}
clear_buffer_mapped(bh);
clear_buffer_req(bh);
clear_buffer_new(bh);
+ clear_buffer_delay(bh);
+ clear_buffer_unwritten(bh);
bh->b_bdev = NULL;
return may_free;
}
if (jh->b_transaction)
__jbd2_journal_temp_unlink_buffer(jh);
+ else
+ jbd2_journal_grab_journal_head(bh);
jh->b_transaction = transaction;
switch (jlist) {
* already started to be used by a subsequent transaction, refile the
* buffer on that transaction's metadata list.
*
- * Called under journal->j_list_lock
- *
+ * Called under j_list_lock
* Called under jbd_lock_bh_state(jh2bh(jh))
+ *
+ * jh and bh may be already free when this function returns
*/
void __jbd2_journal_refile_buffer(struct journal_head *jh)
{
was_dirty = test_clear_buffer_jbddirty(bh);
__jbd2_journal_temp_unlink_buffer(jh);
+ /*
+ * We set b_transaction here because b_next_transaction will inherit
+ * our jh reference and thus __jbd2_journal_file_buffer() must not
+ * take a new one.
+ */
jh->b_transaction = jh->b_next_transaction;
jh->b_next_transaction = NULL;
if (buffer_freed(bh))
}
/*
- * For the unlocked version of this call, also make sure that any
- * hanging journal_head is cleaned up if necessary.
- *
- * __jbd2_journal_refile_buffer is usually called as part of a single locked
- * operation on a buffer_head, in which the caller is probably going to
- * be hooking the journal_head onto other lists. In that case it is up
- * to the caller to remove the journal_head if necessary. For the
- * unlocked jbd2_journal_refile_buffer call, the caller isn't going to be
- * doing anything else to the buffer so we need to do the cleanup
- * ourselves to avoid a jh leak.
- *
- * *** The journal_head may be freed by this call! ***
+ * __jbd2_journal_refile_buffer() with necessary locking added. We take our
+ * bh reference so that we can safely unlock bh.
+ *
+ * The jh and bh may be freed by this call.
*/
void jbd2_journal_refile_buffer(journal_t *journal, struct journal_head *jh)
{
struct buffer_head *bh = jh2bh(jh);
+ /* Get reference so that buffer cannot be freed before we unlock it */
+ get_bh(bh);
jbd_lock_bh_state(bh);
spin_lock(&journal->j_list_lock);
-
__jbd2_journal_refile_buffer(jh);
jbd_unlock_bh_state(bh);
- jbd2_journal_remove_journal_head(bh);
-
spin_unlock(&journal->j_list_lock);
__brelse(bh);
}
jinode->i_next_transaction == transaction)
goto done;
+ /*
+ * We only ever set this variable to 1 so the test is safe. Since
+ * t_need_data_flush is likely to be set, we do the test to save some
+ * cacheline bouncing
+ */
+ if (!transaction->t_need_data_flush)
+ transaction->t_need_data_flush = 1;
/* On some different transaction's list - should be
* the committing one */
if (jinode->i_transaction) {