[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/jbd2/checkpoint.c b/ap/os/linux/linux-3.4.x/fs/jbd2/checkpoint.c
new file mode 100644
index 0000000..86806d5
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/jbd2/checkpoint.c
@@ -0,0 +1,733 @@
+/*
+ * linux/fs/jbd2/checkpoint.c
+ *
+ * Written by Stephen C. Tweedie <sct@redhat.com>, 1999
+ *
+ * Copyright 1999 Red Hat Software --- All Rights Reserved
+ *
+ * This file is part of the Linux kernel and is made available under
+ * the terms of the GNU General Public License, version 2, or at your
+ * option, any later version, incorporated herein by reference.
+ *
+ * Checkpoint routines for the generic filesystem journaling code.
+ * Part of the ext2fs journaling system.
+ *
+ * Checkpointing is the process of ensuring that a section of the log is
+ * committed fully to disk, so that that portion of the log can be
+ * reused.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include <trace/events/jbd2.h>
+
+/*
+ * Unlink a buffer from a transaction checkpoint list.
+ *
+ * Called with j_list_lock held.
+ */
+static inline void __buffer_unlink_first(struct journal_head *jh)
+{
+ transaction_t *transaction = jh->b_cp_transaction;
+
+ jh->b_cpnext->b_cpprev = jh->b_cpprev;
+ jh->b_cpprev->b_cpnext = jh->b_cpnext;
+ if (transaction->t_checkpoint_list == jh) {
+ transaction->t_checkpoint_list = jh->b_cpnext;
+ if (transaction->t_checkpoint_list == jh)
+ transaction->t_checkpoint_list = NULL;
+ }
+}
+
+/*
+ * Unlink a buffer from a transaction checkpoint(io) list.
+ *
+ * Called with j_list_lock held.
+ */
+static inline void __buffer_unlink(struct journal_head *jh)
+{
+ transaction_t *transaction = jh->b_cp_transaction;
+
+ __buffer_unlink_first(jh);
+ if (transaction->t_checkpoint_io_list == jh) {
+ transaction->t_checkpoint_io_list = jh->b_cpnext;
+ if (transaction->t_checkpoint_io_list == jh)
+ transaction->t_checkpoint_io_list = NULL;
+ }
+}
+
+/*
+ * Move a buffer from the checkpoint list to the checkpoint io list
+ *
+ * Called with j_list_lock held
+ */
+static inline void __buffer_relink_io(struct journal_head *jh)
+{
+ transaction_t *transaction = jh->b_cp_transaction;
+
+ __buffer_unlink_first(jh);
+
+ if (!transaction->t_checkpoint_io_list) {
+ jh->b_cpnext = jh->b_cpprev = jh;
+ } else {
+ jh->b_cpnext = transaction->t_checkpoint_io_list;
+ jh->b_cpprev = transaction->t_checkpoint_io_list->b_cpprev;
+ jh->b_cpprev->b_cpnext = jh;
+ jh->b_cpnext->b_cpprev = jh;
+ }
+ transaction->t_checkpoint_io_list = jh;
+}
+
+/*
+ * Try to release a checkpointed buffer from its transaction.
+ * Returns 1 if we released it and 2 if we also released the
+ * whole transaction.
+ *
+ * Requires j_list_lock
+ */
+static int __try_to_free_cp_buf(struct journal_head *jh)
+{
+ int ret = 0;
+ struct buffer_head *bh = jh2bh(jh);
+
+ if (jh->b_transaction == NULL && !buffer_locked(bh) &&
+ !buffer_dirty(bh) && !buffer_write_io_error(bh)) {
+ /*
+ * Get our reference so that bh cannot be freed before
+ * we unlock it
+ */
+ get_bh(bh);
+ JBUFFER_TRACE(jh, "remove from checkpoint list");
+ ret = __jbd2_journal_remove_checkpoint(jh) + 1;
+ BUFFER_TRACE(bh, "release");
+ __brelse(bh);
+ }
+ return ret;
+}
+
+/*
+ * __jbd2_log_wait_for_space: wait until there is space in the journal.
+ *
+ * Called under j-state_lock *only*. It will be unlocked if we have to wait
+ * for a checkpoint to free up some space in the log.
+ */
+void __jbd2_log_wait_for_space(journal_t *journal)
+{
+ int nblocks, space_left;
+ /* assert_spin_locked(&journal->j_state_lock); */
+
+ nblocks = jbd_space_needed(journal);
+ while (__jbd2_log_space_left(journal) < nblocks) {
+ if (journal->j_flags & JBD2_ABORT)
+ return;
+ write_unlock(&journal->j_state_lock);
+ if (current->plug)
+ io_schedule();
+ mutex_lock(&journal->j_checkpoint_mutex);
+
+ /*
+ * Test again, another process may have checkpointed while we
+ * were waiting for the checkpoint lock. If there are no
+ * transactions ready to be checkpointed, try to recover
+ * journal space by calling cleanup_journal_tail(), and if
+ * that doesn't work, by waiting for the currently committing
+ * transaction to complete. If there is absolutely no way
+ * to make progress, this is either a BUG or corrupted
+ * filesystem, so abort the journal and leave a stack
+ * trace for forensic evidence.
+ */
+ write_lock(&journal->j_state_lock);
+ spin_lock(&journal->j_list_lock);
+ nblocks = jbd_space_needed(journal);
+ space_left = __jbd2_log_space_left(journal);
+ if (space_left < nblocks) {
+ int chkpt = journal->j_checkpoint_transactions != NULL;
+ tid_t tid = 0;
+
+ if (journal->j_committing_transaction)
+ tid = journal->j_committing_transaction->t_tid;
+ spin_unlock(&journal->j_list_lock);
+ write_unlock(&journal->j_state_lock);
+ if (chkpt) {
+ jbd2_log_do_checkpoint(journal);
+ } else if (jbd2_cleanup_journal_tail(journal) == 0) {
+ /* We were able to recover space; yay! */
+ ;
+ } else if (tid) {
+ jbd2_log_wait_commit(journal, tid);
+ } else {
+ printk(KERN_ERR "%s: needed %d blocks and "
+ "only had %d space available\n",
+ __func__, nblocks, space_left);
+ printk(KERN_ERR "%s: no way to get more "
+ "journal space in %s\n", __func__,
+ journal->j_devname);
+ WARN_ON(1);
+ jbd2_journal_abort(journal, 0);
+ }
+ write_lock(&journal->j_state_lock);
+ } else {
+ spin_unlock(&journal->j_list_lock);
+ }
+ mutex_unlock(&journal->j_checkpoint_mutex);
+ }
+}
+
+/*
+ * Clean up transaction's list of buffers submitted for io.
+ * We wait for any pending IO to complete and remove any clean
+ * buffers. Note that we take the buffers in the opposite ordering
+ * from the one in which they were submitted for IO.
+ *
+ * Return 0 on success, and return <0 if some buffers have failed
+ * to be written out.
+ *
+ * Called with j_list_lock held.
+ */
+static int __wait_cp_io(journal_t *journal, transaction_t *transaction)
+{
+ struct journal_head *jh;
+ struct buffer_head *bh;
+ tid_t this_tid;
+ int released = 0;
+ int ret = 0;
+
+ this_tid = transaction->t_tid;
+restart:
+ /* Did somebody clean up the transaction in the meanwhile? */
+ if (journal->j_checkpoint_transactions != transaction ||
+ transaction->t_tid != this_tid)
+ return ret;
+ while (!released && transaction->t_checkpoint_io_list) {
+ jh = transaction->t_checkpoint_io_list;
+ bh = jh2bh(jh);
+ get_bh(bh);
+ if (buffer_locked(bh)) {
+ spin_unlock(&journal->j_list_lock);
+ wait_on_buffer(bh);
+ /* the journal_head may have gone by now */
+ BUFFER_TRACE(bh, "brelse");
+ __brelse(bh);
+ spin_lock(&journal->j_list_lock);
+ goto restart;
+ }
+ if (unlikely(buffer_write_io_error(bh)))
+ ret = -EIO;
+
+ /*
+ * Now in whatever state the buffer currently is, we know that
+ * it has been written out and so we can drop it from the list
+ */
+ released = __jbd2_journal_remove_checkpoint(jh);
+ __brelse(bh);
+ }
+
+ return ret;
+}
+
+static void
+__flush_batch(journal_t *journal, int *batch_count)
+{
+ int i;
+ struct blk_plug plug;
+
+ blk_start_plug(&plug);
+ for (i = 0; i < *batch_count; i++)
+ write_dirty_buffer(journal->j_chkpt_bhs[i], WRITE_SYNC);
+ blk_finish_plug(&plug);
+
+ for (i = 0; i < *batch_count; i++) {
+ struct buffer_head *bh = journal->j_chkpt_bhs[i];
+ BUFFER_TRACE(bh, "brelse");
+ __brelse(bh);
+ }
+ *batch_count = 0;
+}
+
+/*
+ * Try to flush one buffer from the checkpoint list to disk.
+ *
+ * Return 1 if something happened which requires us to abort the current
+ * scan of the checkpoint list. Return <0 if the buffer has failed to
+ * be written out.
+ *
+ * Called with j_list_lock held and drops it if 1 is returned
+ */
+static int __process_buffer(journal_t *journal, struct journal_head *jh,
+ int *batch_count, transaction_t *transaction)
+{
+ struct buffer_head *bh = jh2bh(jh);
+ int ret = 0;
+
+ if (buffer_locked(bh)) {
+ get_bh(bh);
+ spin_unlock(&journal->j_list_lock);
+ wait_on_buffer(bh);
+ /* the journal_head may have gone by now */
+ BUFFER_TRACE(bh, "brelse");
+ __brelse(bh);
+ ret = 1;
+ } else if (jh->b_transaction != NULL) {
+ transaction_t *t = jh->b_transaction;
+ tid_t tid = t->t_tid;
+
+ transaction->t_chp_stats.cs_forced_to_close++;
+ spin_unlock(&journal->j_list_lock);
+ if (unlikely(journal->j_flags & JBD2_UNMOUNT))
+ /*
+ * The journal thread is dead; so starting and
+ * waiting for a commit to finish will cause
+ * us to wait for a _very_ long time.
+ */
+ printk(KERN_ERR "JBD2: %s: "
+ "Waiting for Godot: block %llu\n",
+ journal->j_devname,
+ (unsigned long long) bh->b_blocknr);
+ jbd2_log_start_commit(journal, tid);
+ jbd2_log_wait_commit(journal, tid);
+ ret = 1;
+ } else if (!buffer_dirty(bh)) {
+ ret = 1;
+ if (unlikely(buffer_write_io_error(bh)))
+ ret = -EIO;
+ get_bh(bh);
+ BUFFER_TRACE(bh, "remove from checkpoint");
+ __jbd2_journal_remove_checkpoint(jh);
+ spin_unlock(&journal->j_list_lock);
+ __brelse(bh);
+ } else {
+ /*
+ * Important: we are about to write the buffer, and
+ * possibly block, while still holding the journal lock.
+ * We cannot afford to let the transaction logic start
+ * messing around with this buffer before we write it to
+ * disk, as that would break recoverability.
+ */
+ BUFFER_TRACE(bh, "queue");
+ get_bh(bh);
+ J_ASSERT_BH(bh, !buffer_jwrite(bh));
+ journal->j_chkpt_bhs[*batch_count] = bh;
+ __buffer_relink_io(jh);
+ transaction->t_chp_stats.cs_written++;
+ (*batch_count)++;
+ if (*batch_count == JBD2_NR_BATCH) {
+ spin_unlock(&journal->j_list_lock);
+ __flush_batch(journal, batch_count);
+ ret = 1;
+ }
+ }
+ return ret;
+}
+
+/*
+ * Perform an actual checkpoint. We take the first transaction on the
+ * list of transactions to be checkpointed and send all its buffers
+ * to disk. We submit larger chunks of data at once.
+ *
+ * The journal should be locked before calling this function.
+ * Called with j_checkpoint_mutex held.
+ */
+int jbd2_log_do_checkpoint(journal_t *journal)
+{
+ transaction_t *transaction;
+ tid_t this_tid;
+ int result;
+
+ jbd_debug(1, "Start checkpoint\n");
+
+ /*
+ * First thing: if there are any transactions in the log which
+ * don't need checkpointing, just eliminate them from the
+ * journal straight away.
+ */
+ result = jbd2_cleanup_journal_tail(journal);
+ trace_jbd2_checkpoint(journal, result);
+ jbd_debug(1, "cleanup_journal_tail returned %d\n", result);
+ if (result <= 0)
+ return result;
+
+ /*
+ * OK, we need to start writing disk blocks. Take one transaction
+ * and write it.
+ */
+ result = 0;
+ spin_lock(&journal->j_list_lock);
+ if (!journal->j_checkpoint_transactions)
+ goto out;
+ transaction = journal->j_checkpoint_transactions;
+ if (transaction->t_chp_stats.cs_chp_time == 0)
+ transaction->t_chp_stats.cs_chp_time = jiffies;
+ this_tid = transaction->t_tid;
+restart:
+ /*
+ * If someone cleaned up this transaction while we slept, we're
+ * done (maybe it's a new transaction, but it fell at the same
+ * address).
+ */
+ if (journal->j_checkpoint_transactions == transaction &&
+ transaction->t_tid == this_tid) {
+ int batch_count = 0;
+ struct journal_head *jh;
+ int retry = 0, err;
+
+ while (!retry && transaction->t_checkpoint_list) {
+ jh = transaction->t_checkpoint_list;
+ retry = __process_buffer(journal, jh, &batch_count,
+ transaction);
+ if (retry < 0 && !result)
+ result = retry;
+ if (!retry && (need_resched() ||
+ spin_needbreak(&journal->j_list_lock))) {
+ spin_unlock(&journal->j_list_lock);
+ retry = 1;
+ break;
+ }
+ }
+
+ if (batch_count) {
+ if (!retry) {
+ spin_unlock(&journal->j_list_lock);
+ retry = 1;
+ }
+ __flush_batch(journal, &batch_count);
+ }
+
+ if (retry) {
+ spin_lock(&journal->j_list_lock);
+ goto restart;
+ }
+ /*
+ * Now we have cleaned up the first transaction's checkpoint
+ * list. Let's clean up the second one
+ */
+ err = __wait_cp_io(journal, transaction);
+ if (!result)
+ result = err;
+ }
+out:
+ spin_unlock(&journal->j_list_lock);
+ if (result < 0)
+ jbd2_journal_abort(journal, result);
+ else
+ result = jbd2_cleanup_journal_tail(journal);
+
+ return (result < 0) ? result : 0;
+}
+
+/*
+ * Check the list of checkpoint transactions for the journal to see if
+ * we have already got rid of any since the last update of the log tail
+ * in the journal superblock. If so, we can instantly roll the
+ * superblock forward to remove those transactions from the log.
+ *
+ * Return <0 on error, 0 on success, 1 if there was nothing to clean up.
+ *
+ * Called with the journal lock held.
+ *
+ * This is the only part of the journaling code which really needs to be
+ * aware of transaction aborts. Checkpointing involves writing to the
+ * main filesystem area rather than to the journal, so it can proceed
+ * even in abort state, but we must not update the super block if
+ * checkpointing may have failed. Otherwise, we would lose some metadata
+ * buffers which should be written-back to the filesystem.
+ */
+
+int jbd2_cleanup_journal_tail(journal_t *journal)
+{
+ tid_t first_tid;
+ unsigned long blocknr;
+
+ if (is_journal_aborted(journal))
+ return -EIO;
+
+ if (!jbd2_journal_get_log_tail(journal, &first_tid, &blocknr))
+ return 1;
+ J_ASSERT(blocknr != 0);
+
+ /*
+ * 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_flags & JBD2_BARRIER)
+ blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS, NULL);
+
+ return __jbd2_update_log_tail(journal, first_tid, blocknr);
+}
+
+
+/* Checkpoint list management */
+
+/*
+ * journal_clean_one_cp_list
+ *
+ * Find all the written-back checkpoint buffers in the given list and
+ * release them. If 'destroy' is set, clean all buffers unconditionally.
+ *
+ * Called with the journal locked.
+ * Called with j_list_lock held.
+ * Returns number of buffers reaped (for debug)
+ */
+
+static int journal_clean_one_cp_list(struct journal_head *jh, int *released, bool destroy)
+{
+ struct journal_head *last_jh;
+ struct journal_head *next_jh = jh;
+ int ret, freed = 0;
+
+ *released = 0;
+ if (!jh)
+ return 0;
+
+ last_jh = jh->b_cpprev;
+ do {
+ jh = next_jh;
+ next_jh = jh->b_cpnext;
+ if (!destroy)
+ ret = __try_to_free_cp_buf(jh);
+ else
+ ret = __jbd2_journal_remove_checkpoint(jh) + 1;
+ if (ret) {
+ freed++;
+ if (ret == 2) {
+ *released = 1;
+ return freed;
+ }
+ }
+ /*
+ * This function only frees up some memory
+ * if possible so we dont have an obligation
+ * to finish processing. Bail out if preemption
+ * requested:
+ */
+ if (need_resched())
+ return freed;
+ } while (jh != last_jh);
+
+ return freed;
+}
+
+/*
+ * journal_clean_checkpoint_list
+ *
+ * Find all the written-back checkpoint buffers in the journal and release them.
+ *
+ * If 'destroy' is set, release all buffers unconditionally.
+ *
+ * Called with the journal locked.
+ * Called with j_list_lock held.
+ * Returns number of buffers reaped (for debug)
+ */
+
+int __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy)
+{
+ transaction_t *transaction, *last_transaction, *next_transaction;
+ int ret = 0;
+ int released;
+
+ transaction = journal->j_checkpoint_transactions;
+ if (!transaction)
+ goto out;
+
+ last_transaction = transaction->t_cpprev;
+ next_transaction = transaction;
+ do {
+ transaction = next_transaction;
+ next_transaction = transaction->t_cpnext;
+ ret += journal_clean_one_cp_list(transaction->
+ t_checkpoint_list, &released, destroy);
+ /*
+ * This function only frees up some memory if possible so we
+ * dont have an obligation to finish processing. Bail out if
+ * preemption requested:
+ */
+ if (need_resched())
+ goto out;
+ if (released)
+ continue;
+ /*
+ * It is essential that we are as careful as in the case of
+ * t_checkpoint_list with removing the buffer from the list as
+ * we can possibly see not yet submitted buffers on io_list
+ */
+ ret += journal_clean_one_cp_list(transaction->
+ t_checkpoint_io_list, &released, destroy);
+ if (need_resched())
+ goto out;
+ } while (transaction != last_transaction);
+out:
+ return ret;
+}
+
+/*
+ * Remove buffers from all checkpoint lists as journal is aborted and we just
+ * need to free memory
+ */
+void jbd2_journal_destroy_checkpoint(journal_t *journal)
+{
+ /*
+ * We loop because __jbd2_journal_clean_checkpoint_list() may abort
+ * early due to a need of rescheduling.
+ */
+ while (1) {
+ spin_lock(&journal->j_list_lock);
+ if (!journal->j_checkpoint_transactions) {
+ spin_unlock(&journal->j_list_lock);
+ break;
+ }
+ __jbd2_journal_clean_checkpoint_list(journal, true);
+ spin_unlock(&journal->j_list_lock);
+ cond_resched();
+ }
+}
+
+/*
+ * journal_remove_checkpoint: called after a buffer has been committed
+ * to disk (either by being write-back flushed to disk, or being
+ * committed to the log).
+ *
+ * We cannot safely clean a transaction out of the log until all of the
+ * buffer updates committed in that transaction have safely been stored
+ * elsewhere on disk. To achieve this, all of the buffers in a
+ * transaction need to be maintained on the transaction's checkpoint
+ * lists until they have been rewritten, at which point this function is
+ * called to remove the buffer from the existing transaction's
+ * checkpoint lists.
+ *
+ * The function returns 1 if it frees the transaction, 0 otherwise.
+ * The function can free jh and bh.
+ *
+ * This function is called with j_list_lock held.
+ */
+int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
+{
+ struct transaction_chp_stats_s *stats;
+ transaction_t *transaction;
+ journal_t *journal;
+ int ret = 0;
+
+ JBUFFER_TRACE(jh, "entry");
+
+ if ((transaction = jh->b_cp_transaction) == NULL) {
+ JBUFFER_TRACE(jh, "not on transaction");
+ goto out;
+ }
+ journal = transaction->t_journal;
+
+ JBUFFER_TRACE(jh, "removing from transaction");
+ __buffer_unlink(jh);
+ jh->b_cp_transaction = NULL;
+ jbd2_journal_put_journal_head(jh);
+
+ if (transaction->t_checkpoint_list != NULL ||
+ transaction->t_checkpoint_io_list != NULL)
+ goto out;
+
+ /*
+ * There is one special case to worry about: if we have just pulled the
+ * buffer off a running or committing transaction's checkpoing list,
+ * then even if the checkpoint list is empty, the transaction obviously
+ * cannot be dropped!
+ *
+ * The locking here around t_state is a bit sleazy.
+ * See the comment at the end of jbd2_journal_commit_transaction().
+ */
+ if (transaction->t_state != T_FINISHED)
+ goto out;
+
+ /* OK, that was the last buffer for the transaction: we can now
+ safely remove this transaction from the log */
+ stats = &transaction->t_chp_stats;
+ if (stats->cs_chp_time)
+ stats->cs_chp_time = jbd2_time_diff(stats->cs_chp_time,
+ jiffies);
+ trace_jbd2_checkpoint_stats(journal->j_fs_dev->bd_dev,
+ transaction->t_tid, stats);
+
+ __jbd2_journal_drop_transaction(journal, transaction);
+ jbd2_journal_free_transaction(transaction);
+
+ /* Just in case anybody was waiting for more transactions to be
+ checkpointed... */
+ wake_up(&journal->j_wait_logspace);
+ ret = 1;
+out:
+ return ret;
+}
+
+/*
+ * journal_insert_checkpoint: put a committed buffer onto a checkpoint
+ * list so that we know when it is safe to clean the transaction out of
+ * the log.
+ *
+ * Called with the journal locked.
+ * Called with j_list_lock held.
+ */
+void __jbd2_journal_insert_checkpoint(struct journal_head *jh,
+ transaction_t *transaction)
+{
+ JBUFFER_TRACE(jh, "entry");
+ J_ASSERT_JH(jh, buffer_dirty(jh2bh(jh)) || buffer_jbddirty(jh2bh(jh)));
+ J_ASSERT_JH(jh, jh->b_cp_transaction == NULL);
+
+ /* Get reference for checkpointing transaction */
+ jbd2_journal_grab_journal_head(jh2bh(jh));
+ jh->b_cp_transaction = transaction;
+
+ if (!transaction->t_checkpoint_list) {
+ jh->b_cpnext = jh->b_cpprev = jh;
+ } else {
+ jh->b_cpnext = transaction->t_checkpoint_list;
+ jh->b_cpprev = transaction->t_checkpoint_list->b_cpprev;
+ jh->b_cpprev->b_cpnext = jh;
+ jh->b_cpnext->b_cpprev = jh;
+ }
+ transaction->t_checkpoint_list = jh;
+}
+
+/*
+ * We've finished with this transaction structure: adios...
+ *
+ * The transaction must have no links except for the checkpoint by this
+ * point.
+ *
+ * Called with the journal locked.
+ * Called with j_list_lock held.
+ */
+
+void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transaction)
+{
+ assert_spin_locked(&journal->j_list_lock);
+ if (transaction->t_cpnext) {
+ transaction->t_cpnext->t_cpprev = transaction->t_cpprev;
+ transaction->t_cpprev->t_cpnext = transaction->t_cpnext;
+ if (journal->j_checkpoint_transactions == transaction)
+ journal->j_checkpoint_transactions =
+ transaction->t_cpnext;
+ if (journal->j_checkpoint_transactions == transaction)
+ journal->j_checkpoint_transactions = NULL;
+ }
+
+ J_ASSERT(transaction->t_state == T_FINISHED);
+ J_ASSERT(transaction->t_buffers == NULL);
+ J_ASSERT(transaction->t_forget == NULL);
+ J_ASSERT(transaction->t_iobuf_list == NULL);
+ J_ASSERT(transaction->t_shadow_list == NULL);
+ J_ASSERT(transaction->t_log_list == NULL);
+ J_ASSERT(transaction->t_checkpoint_list == NULL);
+ J_ASSERT(transaction->t_checkpoint_io_list == NULL);
+ J_ASSERT(atomic_read(&transaction->t_updates) == 0);
+ J_ASSERT(journal->j_committing_transaction != transaction);
+ J_ASSERT(journal->j_running_transaction != transaction);
+
+ trace_jbd2_drop_transaction(journal, transaction);
+
+ jbd_debug(1, "Dropping transaction %d, all done\n", transaction->t_tid);
+}