Merge remote-tracking branch 'asoc/fix/rt5645' into asoc-fix-rt5645

1 files changed, 0 insertions, 1021 deletions

diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
deleted file mode 100644
index bb217dcb41af..000000000000
--- a/fs/jbd/commit.c
+++ /dev/null
@@ -1,1021 +0,0 @@
-/*
- * linux/fs/jbd/commit.c
- *
- * Written by Stephen C. Tweedie <[email protected]>, 1998
- *
- * Copyright 1998 Red Hat corp --- 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.
- *
- * Journal commit routines for the generic filesystem journaling code;
- * part of the ext2fs journaling system.
- */
-
-#include <linux/time.h>
-#include <linux/fs.h>
-#include <linux/jbd.h>
-#include <linux/errno.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/bio.h>
-#include <linux/blkdev.h>
-#include <trace/events/jbd.h>
-
-/*
- * Default IO end handler for temporary BJ_IO buffer_heads.
- */
-static void journal_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
-{
-	BUFFER_TRACE(bh, "");
-	if (uptodate)
-		set_buffer_uptodate(bh);
-	else
-		clear_buffer_uptodate(bh);
-	unlock_buffer(bh);
-}
-
-/*
- * When an ext3-ordered file is truncated, it is possible that many pages are
- * not successfully freed, because they are attached to a committing transaction.
- * After the transaction commits, these pages are left on the LRU, with no
- * ->mapping, and with attached buffers.  These pages are trivially reclaimable
- * by the VM, but their apparent absence upsets the VM accounting, and it makes
- * the numbers in /proc/meminfo look odd.
- *
- * So here, we have a buffer which has just come off the forget list.  Look to
- * see if we can strip all buffers from the backing page.
- *
- * Called under journal->j_list_lock.  The caller provided us with a ref
- * against the buffer, and we drop that here.
- */
-static void release_buffer_page(struct buffer_head *bh)
-{
-	struct page *page;
-
-	if (buffer_dirty(bh))
-		goto nope;
-	if (atomic_read(&bh->b_count) != 1)
-		goto nope;
-	page = bh->b_page;
-	if (!page)
-		goto nope;
-	if (page->mapping)
-		goto nope;
-
-	/* OK, it's a truncated page */
-	if (!trylock_page(page))
-		goto nope;
-
-	page_cache_get(page);
-	__brelse(bh);
-	try_to_free_buffers(page);
-	unlock_page(page);
-	page_cache_release(page);
-	return;
-
-nope:
-	__brelse(bh);
-}
-
-/*
- * Decrement reference counter for data buffer. If it has been marked
- * 'BH_Freed', release it and the page to which it belongs if possible.
- */
-static void release_data_buffer(struct buffer_head *bh)
-{
-	if (buffer_freed(bh)) {
-		WARN_ON_ONCE(buffer_dirty(bh));
-		clear_buffer_freed(bh);
-		clear_buffer_mapped(bh);
-		clear_buffer_new(bh);
-		clear_buffer_req(bh);
-		bh->b_bdev = NULL;
-		release_buffer_page(bh);
-	} else
-		put_bh(bh);
-}
-
-/*
- * Try to acquire jbd_lock_bh_state() against the buffer, when j_list_lock is
- * held.  For ranking reasons we must trylock.  If we lose, schedule away and
- * return 0.  j_list_lock is dropped in this case.
- */
-static int inverted_lock(journal_t *journal, struct buffer_head *bh)
-{
-	if (!jbd_trylock_bh_state(bh)) {
-		spin_unlock(&journal->j_list_lock);
-		schedule();
-		return 0;
-	}
-	return 1;
-}
-
-/* Done it all: now write the commit record.  We should have
- * cleaned up our previous buffers by now, so if we are in abort
- * mode we can now just skip the rest of the journal write
- * entirely.
- *
- * Returns 1 if the journal needs to be aborted or 0 on success
- */
-static int journal_write_commit_record(journal_t *journal,
-					transaction_t *commit_transaction)
-{
-	struct journal_head *descriptor;
-	struct buffer_head *bh;
-	journal_header_t *header;
-	int ret;
-
-	if (is_journal_aborted(journal))
-		return 0;
-
-	descriptor = journal_get_descriptor_buffer(journal);
-	if (!descriptor)
-		return 1;
-
-	bh = jh2bh(descriptor);
-
-	header = (journal_header_t *)(bh->b_data);
-	header->h_magic = cpu_to_be32(JFS_MAGIC_NUMBER);
-	header->h_blocktype = cpu_to_be32(JFS_COMMIT_BLOCK);
-	header->h_sequence = cpu_to_be32(commit_transaction->t_tid);
-
-	JBUFFER_TRACE(descriptor, "write commit block");
-	set_buffer_dirty(bh);
-
-	if (journal->j_flags & JFS_BARRIER)
-		ret = __sync_dirty_buffer(bh, WRITE_SYNC | WRITE_FLUSH_FUA);
-	else
-		ret = sync_dirty_buffer(bh);
-
-	put_bh(bh);		/* One for getblk() */
-	journal_put_journal_head(descriptor);
-
-	return (ret == -EIO);
-}
-
-static void journal_do_submit_data(struct buffer_head **wbuf, int bufs,
-				   int write_op)
-{
-	int i;
-
-	for (i = 0; i < bufs; i++) {
-		wbuf[i]->b_end_io = end_buffer_write_sync;
-		/*
-		 * Here we write back pagecache data that may be mmaped. Since
-		 * we cannot afford to clean the page and set PageWriteback
-		 * here due to lock ordering (page lock ranks above transaction
-		 * start), the data can change while IO is in flight. Tell the
-		 * block layer it should bounce the bio pages if stable data
-		 * during write is required.
-		 *
-		 * We use up our safety reference in submit_bh().
-		 */
-		_submit_bh(write_op, wbuf[i], 1 << BIO_SNAP_STABLE);
-	}
-}
-
-/*
- *  Submit all the data buffers to disk
- */
-static int journal_submit_data_buffers(journal_t *journal,
-				       transaction_t *commit_transaction,
-				       int write_op)
-{
-	struct journal_head *jh;
-	struct buffer_head *bh;
-	int locked;
-	int bufs = 0;
-	struct buffer_head **wbuf = journal->j_wbuf;
-	int err = 0;
-
-	/*
-	 * Whenever we unlock the journal and sleep, things can get added
-	 * onto ->t_sync_datalist, so we have to keep looping back to
-	 * write_out_data until we *know* that the list is empty.
-	 *
-	 * Cleanup any flushed data buffers from the data list.  Even in
-	 * abort mode, we want to flush this out as soon as possible.
-	 */
-write_out_data:
-	cond_resched();
-	spin_lock(&journal->j_list_lock);
-
-	while (commit_transaction->t_sync_datalist) {
-		jh = commit_transaction->t_sync_datalist;
-		bh = jh2bh(jh);
-		locked = 0;
-
-		/* Get reference just to make sure buffer does not disappear
-		 * when we are forced to drop various locks */
-		get_bh(bh);
-		/* If the buffer is dirty, we need to submit IO and hence
-		 * we need the buffer lock. We try to lock the buffer without
-		 * blocking. If we fail, we need to drop j_list_lock and do
-		 * blocking lock_buffer().
-		 */
-		if (buffer_dirty(bh)) {
-			if (!trylock_buffer(bh)) {
-				BUFFER_TRACE(bh, "needs blocking lock");
-				spin_unlock(&journal->j_list_lock);
-				trace_jbd_do_submit_data(journal,
-						     commit_transaction);
-				/* Write out all data to prevent deadlocks */
-				journal_do_submit_data(wbuf, bufs, write_op);
-				bufs = 0;
-				lock_buffer(bh);
-				spin_lock(&journal->j_list_lock);
-			}
-			locked = 1;
-		}
-		/* We have to get bh_state lock. Again out of order, sigh. */
-		if (!inverted_lock(journal, bh)) {
-			jbd_lock_bh_state(bh);
-			spin_lock(&journal->j_list_lock);
-		}
-		/* Someone already cleaned up the buffer? */
-		if (!buffer_jbd(bh) || bh2jh(bh) != jh
-			|| jh->b_transaction != commit_transaction
-			|| jh->b_jlist != BJ_SyncData) {
-			jbd_unlock_bh_state(bh);
-			if (locked)
-				unlock_buffer(bh);
-			BUFFER_TRACE(bh, "already cleaned up");
-			release_data_buffer(bh);
-			continue;
-		}
-		if (locked && test_clear_buffer_dirty(bh)) {
-			BUFFER_TRACE(bh, "needs writeout, adding to array");
-			wbuf[bufs++] = bh;
-			__journal_file_buffer(jh, commit_transaction,
-						BJ_Locked);
-			jbd_unlock_bh_state(bh);
-			if (bufs == journal->j_wbufsize) {
-				spin_unlock(&journal->j_list_lock);
-				trace_jbd_do_submit_data(journal,
-						     commit_transaction);
-				journal_do_submit_data(wbuf, bufs, write_op);
-				bufs = 0;
-				goto write_out_data;
-			}
-		} else if (!locked && buffer_locked(bh)) {
-			__journal_file_buffer(jh, commit_transaction,
-						BJ_Locked);
-			jbd_unlock_bh_state(bh);
-			put_bh(bh);
-		} else {
-			BUFFER_TRACE(bh, "writeout complete: unfile");
-			if (unlikely(!buffer_uptodate(bh)))
-				err = -EIO;
-			__journal_unfile_buffer(jh);
-			jbd_unlock_bh_state(bh);
-			if (locked)
-				unlock_buffer(bh);
-			release_data_buffer(bh);
-		}
-
-		if (need_resched() || spin_needbreak(&journal->j_list_lock)) {
-			spin_unlock(&journal->j_list_lock);
-			goto write_out_data;
-		}
-	}
-	spin_unlock(&journal->j_list_lock);
-	trace_jbd_do_submit_data(journal, commit_transaction);
-	journal_do_submit_data(wbuf, bufs, write_op);
-
-	return err;
-}
-
-/*
- * journal_commit_transaction
- *
- * The primary function for committing a transaction to the log.  This
- * function is called by the journal thread to begin a complete commit.
- */
-void journal_commit_transaction(journal_t *journal)
-{
-	transaction_t *commit_transaction;
-	struct journal_head *jh, *new_jh, *descriptor;
-	struct buffer_head **wbuf = journal->j_wbuf;
-	int bufs;
-	int flags;
-	int err;
-	unsigned int blocknr;
-	ktime_t start_time;
-	u64 commit_time;
-	char *tagp = NULL;
-	journal_header_t *header;
-	journal_block_tag_t *tag = NULL;
-	int space_left = 0;
-	int first_tag = 0;
-	int tag_flag;
-	int i;
-	struct blk_plug plug;
-	int write_op = WRITE;
-
-	/*
-	 * First job: lock down the current transaction and wait for
-	 * all outstanding updates to complete.
-	 */
-
-	/* Do we need to erase the effects of a prior journal_flush? */
-	if (journal->j_flags & JFS_FLUSHED) {
-		jbd_debug(3, "super block updated\n");
-		mutex_lock(&journal->j_checkpoint_mutex);
-		/*
-		 * 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.
-		 */
-		journal_update_sb_log_tail(journal, journal->j_tail_sequence,
-					   journal->j_tail, WRITE_SYNC);
-		mutex_unlock(&journal->j_checkpoint_mutex);
-	} else {
-		jbd_debug(3, "superblock not updated\n");
-	}
-
-	J_ASSERT(journal->j_running_transaction != NULL);
-	J_ASSERT(journal->j_committing_transaction == NULL);
-
-	commit_transaction = journal->j_running_transaction;
-
-	trace_jbd_start_commit(journal, commit_transaction);
-	jbd_debug(1, "JBD: starting commit of transaction %d\n",
-			commit_transaction->t_tid);
-
-	spin_lock(&journal->j_state_lock);
-	J_ASSERT(commit_transaction->t_state == T_RUNNING);
-	commit_transaction->t_state = T_LOCKED;
-
-	trace_jbd_commit_locking(journal, commit_transaction);
-	spin_lock(&commit_transaction->t_handle_lock);
-	while (commit_transaction->t_updates) {
-		DEFINE_WAIT(wait);
-
-		prepare_to_wait(&journal->j_wait_updates, &wait,
-					TASK_UNINTERRUPTIBLE);
-		if (commit_transaction->t_updates) {
-			spin_unlock(&commit_transaction->t_handle_lock);
-			spin_unlock(&journal->j_state_lock);
-			schedule();
-			spin_lock(&journal->j_state_lock);
-			spin_lock(&commit_transaction->t_handle_lock);
-		}
-		finish_wait(&journal->j_wait_updates, &wait);
-	}
-	spin_unlock(&commit_transaction->t_handle_lock);
-
-	J_ASSERT (commit_transaction->t_outstanding_credits <=
-			journal->j_max_transaction_buffers);
-
-	/*
-	 * First thing we are allowed to do is to discard any remaining
-	 * BJ_Reserved buffers.  Note, it is _not_ permissible to assume
-	 * that there are no such buffers: if a large filesystem
-	 * operation like a truncate needs to split itself over multiple
-	 * transactions, then it may try to do a journal_restart() while
-	 * there are still BJ_Reserved buffers outstanding.  These must
-	 * be released cleanly from the current transaction.
-	 *
-	 * In this case, the filesystem must still reserve write access
-	 * again before modifying the buffer in the new transaction, but
-	 * we do not require it to remember exactly which old buffers it
-	 * has reserved.  This is consistent with the existing behaviour
-	 * that multiple journal_get_write_access() calls to the same
-	 * buffer are perfectly permissible.
-	 */
-	while (commit_transaction->t_reserved_list) {
-		jh = commit_transaction->t_reserved_list;
-		JBUFFER_TRACE(jh, "reserved, unused: refile");
-		/*
-		 * A journal_get_undo_access()+journal_release_buffer() may
-		 * leave undo-committed data.
-		 */
-		if (jh->b_committed_data) {
-			struct buffer_head *bh = jh2bh(jh);
-
-			jbd_lock_bh_state(bh);
-			jbd_free(jh->b_committed_data, bh->b_size);
-			jh->b_committed_data = NULL;
-			jbd_unlock_bh_state(bh);
-		}
-		journal_refile_buffer(journal, jh);
-	}
-
-	/*
-	 * Now try to drop any written-back buffers from the journal's
-	 * checkpoint lists.  We do this *before* commit because it potentially
-	 * frees some memory
-	 */
-	spin_lock(&journal->j_list_lock);
-	__journal_clean_checkpoint_list(journal);
-	spin_unlock(&journal->j_list_lock);
-
-	jbd_debug (3, "JBD: commit phase 1\n");
-
-	/*
-	 * Clear revoked flag to reflect there is no revoked buffers
-	 * in the next transaction which is going to be started.
-	 */
-	journal_clear_buffer_revoked_flags(journal);
-
-	/*
-	 * Switch to a new revoke table.
-	 */
-	journal_switch_revoke_table(journal);
-
-	trace_jbd_commit_flushing(journal, commit_transaction);
-	commit_transaction->t_state = T_FLUSH;
-	journal->j_committing_transaction = commit_transaction;
-	journal->j_running_transaction = NULL;
-	start_time = ktime_get();
-	commit_transaction->t_log_start = journal->j_head;
-	wake_up(&journal->j_wait_transaction_locked);
-	spin_unlock(&journal->j_state_lock);
-
-	jbd_debug (3, "JBD: commit phase 2\n");
-
-	if (tid_geq(journal->j_commit_waited, commit_transaction->t_tid))
-		write_op = WRITE_SYNC;
-
-	/*
-	 * Now start flushing things to disk, in the order they appear
-	 * on the transaction lists.  Data blocks go first.
-	 */
-	blk_start_plug(&plug);
-	err = journal_submit_data_buffers(journal, commit_transaction,
-					  write_op);
-	blk_finish_plug(&plug);
-
-	/*
-	 * Wait for all previously submitted IO to complete.
-	 */
-	spin_lock(&journal->j_list_lock);
-	while (commit_transaction->t_locked_list) {
-		struct buffer_head *bh;
-
-		jh = commit_transaction->t_locked_list->b_tprev;
-		bh = jh2bh(jh);
-		get_bh(bh);
-		if (buffer_locked(bh)) {
-			spin_unlock(&journal->j_list_lock);
-			wait_on_buffer(bh);
-			spin_lock(&journal->j_list_lock);
-		}
-		if (unlikely(!buffer_uptodate(bh))) {
-			if (!trylock_page(bh->b_page)) {
-				spin_unlock(&journal->j_list_lock);
-				lock_page(bh->b_page);
-				spin_lock(&journal->j_list_lock);
-			}
-			if (bh->b_page->mapping)
-				set_bit(AS_EIO, &bh->b_page->mapping->flags);
-
-			unlock_page(bh->b_page);
-			SetPageError(bh->b_page);
-			err = -EIO;
-		}
-		if (!inverted_lock(journal, bh)) {
-			put_bh(bh);
-			spin_lock(&journal->j_list_lock);
-			continue;
-		}
-		if (buffer_jbd(bh) && bh2jh(bh) == jh &&
-		    jh->b_transaction == commit_transaction &&
-		    jh->b_jlist == BJ_Locked)
-			__journal_unfile_buffer(jh);
-		jbd_unlock_bh_state(bh);
-		release_data_buffer(bh);
-		cond_resched_lock(&journal->j_list_lock);
-	}
-	spin_unlock(&journal->j_list_lock);
-
-	if (err) {
-		char b[BDEVNAME_SIZE];
-
-		printk(KERN_WARNING
-			"JBD: Detected IO errors while flushing file data "
-			"on %s\n", bdevname(journal->j_fs_dev, b));
-		if (journal->j_flags & JFS_ABORT_ON_SYNCDATA_ERR)
-			journal_abort(journal, err);
-		err = 0;
-	}
-
-	blk_start_plug(&plug);
-
-	journal_write_revoke_records(journal, commit_transaction, write_op);
-
-	/*
-	 * If we found any dirty or locked buffers, then we should have
-	 * looped back up to the write_out_data label.  If there weren't
-	 * any then journal_clean_data_list should have wiped the list
-	 * clean by now, so check that it is in fact empty.
-	 */
-	J_ASSERT (commit_transaction->t_sync_datalist == NULL);
-
-	jbd_debug (3, "JBD: commit phase 3\n");
-
-	/*
-	 * Way to go: we have now written out all of the data for a
-	 * transaction!  Now comes the tricky part: we need to write out
-	 * metadata.  Loop over the transaction's entire buffer list:
-	 */
-	spin_lock(&journal->j_state_lock);
-	commit_transaction->t_state = T_COMMIT;
-	spin_unlock(&journal->j_state_lock);
-
-	trace_jbd_commit_logging(journal, commit_transaction);
-	J_ASSERT(commit_transaction->t_nr_buffers <=
-		 commit_transaction->t_outstanding_credits);
-
-	descriptor = NULL;
-	bufs = 0;
-	while (commit_transaction->t_buffers) {
-
-		/* Find the next buffer to be journaled... */
-
-		jh = commit_transaction->t_buffers;
-
-		/* If we're in abort mode, we just un-journal the buffer and
-		   release it. */
-
-		if (is_journal_aborted(journal)) {
-			clear_buffer_jbddirty(jh2bh(jh));
-			JBUFFER_TRACE(jh, "journal is aborting: refile");
-			journal_refile_buffer(journal, jh);
-			/* If that was the last one, we need to clean up
-			 * any descriptor buffers which may have been
-			 * already allocated, even if we are now
-			 * aborting. */
-			if (!commit_transaction->t_buffers)
-				goto start_journal_io;
-			continue;
-		}
-
-		/* Make sure we have a descriptor block in which to
-		   record the metadata buffer. */
-
-		if (!descriptor) {
-			struct buffer_head *bh;
-
-			J_ASSERT (bufs == 0);
-
-			jbd_debug(4, "JBD: get descriptor\n");
-
-			descriptor = journal_get_descriptor_buffer(journal);
-			if (!descriptor) {
-				journal_abort(journal, -EIO);
-				continue;
-			}
-
-			bh = jh2bh(descriptor);
-			jbd_debug(4, "JBD: got buffer %llu (%p)\n",
-				(unsigned long long)bh->b_blocknr, bh->b_data);
-			header = (journal_header_t *)&bh->b_data[0];
-			header->h_magic     = cpu_to_be32(JFS_MAGIC_NUMBER);
-			header->h_blocktype = cpu_to_be32(JFS_DESCRIPTOR_BLOCK);
-			header->h_sequence  = cpu_to_be32(commit_transaction->t_tid);
-
-			tagp = &bh->b_data[sizeof(journal_header_t)];
-			space_left = bh->b_size - sizeof(journal_header_t);
-			first_tag = 1;
-			set_buffer_jwrite(bh);
-			set_buffer_dirty(bh);
-			wbuf[bufs++] = bh;
-
-			/* Record it so that we can wait for IO
-                           completion later */
-			BUFFER_TRACE(bh, "ph3: file as descriptor");
-			journal_file_buffer(descriptor, commit_transaction,
-					BJ_LogCtl);
-		}
-
-		/* Where is the buffer to be written? */
-
-		err = journal_next_log_block(journal, &blocknr);
-		/* If the block mapping failed, just abandon the buffer
-		   and repeat this loop: we'll fall into the
-		   refile-on-abort condition above. */
-		if (err) {
-			journal_abort(journal, err);
-			continue;
-		}
-
-		/*
-		 * start_this_handle() uses t_outstanding_credits to determine
-		 * the free space in the log, but this counter is changed
-		 * by journal_next_log_block() also.
-		 */
-		commit_transaction->t_outstanding_credits--;
-
-		/* Bump b_count to prevent truncate from stumbling over
-                   the shadowed buffer!  @@@ This can go if we ever get
-                   rid of the BJ_IO/BJ_Shadow pairing of buffers. */
-		get_bh(jh2bh(jh));
-
-		/* Make a temporary IO buffer with which to write it out
-                   (this will requeue both the metadata buffer and the
-                   temporary IO buffer). new_bh goes on BJ_IO*/
-
-		set_buffer_jwrite(jh2bh(jh));
-		/*
-		 * akpm: journal_write_metadata_buffer() sets
-		 * new_bh->b_transaction to commit_transaction.
-		 * We need to clean this up before we release new_bh
-		 * (which is of type BJ_IO)
-		 */
-		JBUFFER_TRACE(jh, "ph3: write metadata");
-		flags = journal_write_metadata_buffer(commit_transaction,
-						      jh, &new_jh, blocknr);
-		set_buffer_jwrite(jh2bh(new_jh));
-		wbuf[bufs++] = jh2bh(new_jh);
-
-		/* Record the new block's tag in the current descriptor
-                   buffer */
-
-		tag_flag = 0;
-		if (flags & 1)
-			tag_flag |= JFS_FLAG_ESCAPE;
-		if (!first_tag)
-			tag_flag |= JFS_FLAG_SAME_UUID;
-
-		tag = (journal_block_tag_t *) tagp;
-		tag->t_blocknr = cpu_to_be32(jh2bh(jh)->b_blocknr);
-		tag->t_flags = cpu_to_be32(tag_flag);
-		tagp += sizeof(journal_block_tag_t);
-		space_left -= sizeof(journal_block_tag_t);
-
-		if (first_tag) {
-			memcpy (tagp, journal->j_uuid, 16);
-			tagp += 16;
-			space_left -= 16;
-			first_tag = 0;
-		}
-
-		/* If there's no more to do, or if the descriptor is full,
-		   let the IO rip! */
-
-		if (bufs == journal->j_wbufsize ||
-		    commit_transaction->t_buffers == NULL ||
-		    space_left < sizeof(journal_block_tag_t) + 16) {
-
-			jbd_debug(4, "JBD: Submit %d IOs\n", bufs);
-
-			/* Write an end-of-descriptor marker before
-                           submitting the IOs.  "tag" still points to
-                           the last tag we set up. */
-
-			tag->t_flags |= cpu_to_be32(JFS_FLAG_LAST_TAG);
-
-start_journal_io:
-			for (i = 0; i < bufs; i++) {
-				struct buffer_head *bh = wbuf[i];
-				lock_buffer(bh);
-				clear_buffer_dirty(bh);
-				set_buffer_uptodate(bh);
-				bh->b_end_io = journal_end_buffer_io_sync;
-				/*
-				 * In data=journal mode, here we can end up
-				 * writing pagecache data that might be
-				 * mmapped. Since we can't afford to clean the
-				 * page and set PageWriteback (see the comment
-				 * near the other use of _submit_bh()), the
-				 * data can change while the write is in
-				 * flight.  Tell the block layer to bounce the
-				 * bio pages if stable pages are required.
-				 */
-				_submit_bh(write_op, bh, 1 << BIO_SNAP_STABLE);
-			}
-			cond_resched();
-
-			/* Force a new descriptor to be generated next
-                           time round the loop. */
-			descriptor = NULL;
-			bufs = 0;
-		}
-	}
-
-	blk_finish_plug(&plug);
-
-	/* Lo and behold: we have just managed to send a transaction to
-           the log.  Before we can commit it, wait for the IO so far to
-           complete.  Control buffers being written are on the
-           transaction's t_log_list queue, and metadata buffers are on
-           the t_iobuf_list queue.
-
-	   Wait for the buffers in reverse order.  That way we are
-	   less likely to be woken up until all IOs have completed, and
-	   so we incur less scheduling load.
-	*/
-
-	jbd_debug(3, "JBD: commit phase 4\n");
-
-	/*
-	 * akpm: these are BJ_IO, and j_list_lock is not needed.
-	 * See __journal_try_to_free_buffer.
-	 */
-wait_for_iobuf:
-	while (commit_transaction->t_iobuf_list != NULL) {
-		struct buffer_head *bh;
-
-		jh = commit_transaction->t_iobuf_list->b_tprev;
-		bh = jh2bh(jh);
-		if (buffer_locked(bh)) {
-			wait_on_buffer(bh);
-			goto wait_for_iobuf;
-		}
-		if (cond_resched())
-			goto wait_for_iobuf;
-
-		if (unlikely(!buffer_uptodate(bh)))
-			err = -EIO;
-
-		clear_buffer_jwrite(bh);
-
-		JBUFFER_TRACE(jh, "ph4: unfile after journal write");
-		journal_unfile_buffer(journal, jh);
-
-		/*
-		 * ->t_iobuf_list should contain only dummy buffer_heads
-		 * which were created by journal_write_metadata_buffer().
-		 */
-		BUFFER_TRACE(bh, "dumping temporary bh");
-		journal_put_journal_head(jh);
-		__brelse(bh);
-		J_ASSERT_BH(bh, atomic_read(&bh->b_count) == 0);
-		free_buffer_head(bh);
-
-		/* We also have to unlock and free the corresponding
-                   shadowed buffer */
-		jh = commit_transaction->t_shadow_list->b_tprev;
-		bh = jh2bh(jh);
-		clear_buffer_jwrite(bh);
-		J_ASSERT_BH(bh, buffer_jbddirty(bh));
-
-		/* The metadata is now released for reuse, but we need
-                   to remember it against this transaction so that when
-                   we finally commit, we can do any checkpointing
-                   required. */
-		JBUFFER_TRACE(jh, "file as BJ_Forget");
-		journal_file_buffer(jh, commit_transaction, BJ_Forget);
-		/*
-		 * Wake up any transactions which were waiting for this
-		 * IO to complete. The barrier must be here so that changes
-		 * by journal_file_buffer() take effect before wake_up_bit()
-		 * does the waitqueue check.
-		 */
-		smp_mb();
-		wake_up_bit(&bh->b_state, BH_Unshadow);
-		JBUFFER_TRACE(jh, "brelse shadowed buffer");
-		__brelse(bh);
-	}
-
-	J_ASSERT (commit_transaction->t_shadow_list == NULL);
-
-	jbd_debug(3, "JBD: commit phase 5\n");
-
-	/* Here we wait for the revoke record and descriptor record buffers */
- wait_for_ctlbuf:
-	while (commit_transaction->t_log_list != NULL) {
-		struct buffer_head *bh;
-
-		jh = commit_transaction->t_log_list->b_tprev;
-		bh = jh2bh(jh);
-		if (buffer_locked(bh)) {
-			wait_on_buffer(bh);
-			goto wait_for_ctlbuf;
-		}
-		if (cond_resched())
-			goto wait_for_ctlbuf;
-
-		if (unlikely(!buffer_uptodate(bh)))
-			err = -EIO;
-
-		BUFFER_TRACE(bh, "ph5: control buffer writeout done: unfile");
-		clear_buffer_jwrite(bh);
-		journal_unfile_buffer(journal, jh);
-		journal_put_journal_head(jh);
-		__brelse(bh);		/* One for getblk */
-		/* AKPM: bforget here */
-	}
-
-	if (err)
-		journal_abort(journal, err);
-
-	jbd_debug(3, "JBD: commit phase 6\n");
-
-	/* All metadata is written, now write commit record and do cleanup */
-	spin_lock(&journal->j_state_lock);
-	J_ASSERT(commit_transaction->t_state == T_COMMIT);
-	commit_transaction->t_state = T_COMMIT_RECORD;
-	spin_unlock(&journal->j_state_lock);
-
-	if (journal_write_commit_record(journal, commit_transaction))
-		err = -EIO;
-
-	if (err)
-		journal_abort(journal, err);
-
-	/* End of a transaction!  Finally, we can do checkpoint
-           processing: any buffers committed as a result of this
-           transaction can be removed from any checkpoint list it was on
-           before. */
-
-	jbd_debug(3, "JBD: commit phase 7\n");
-
-	J_ASSERT(commit_transaction->t_sync_datalist == NULL);
-	J_ASSERT(commit_transaction->t_buffers == NULL);
-	J_ASSERT(commit_transaction->t_checkpoint_list == NULL);
-	J_ASSERT(commit_transaction->t_iobuf_list == NULL);
-	J_ASSERT(commit_transaction->t_shadow_list == NULL);
-	J_ASSERT(commit_transaction->t_log_list == NULL);
-
-restart_loop:
-	/*
-	 * As there are other places (journal_unmap_buffer()) adding buffers
-	 * to this list we have to be careful and hold the j_list_lock.
-	 */
-	spin_lock(&journal->j_list_lock);
-	while (commit_transaction->t_forget) {
-		transaction_t *cp_transaction;
-		struct buffer_head *bh;
-		int try_to_free = 0;
-
-		jh = commit_transaction->t_forget;
-		spin_unlock(&journal->j_list_lock);
-		bh = jh2bh(jh);
-		/*
-		 * Get a reference so that bh cannot be freed before we are
-		 * done with it.
-		 */
-		get_bh(bh);
-		jbd_lock_bh_state(bh);
-		J_ASSERT_JH(jh,	jh->b_transaction == commit_transaction ||
-			jh->b_transaction == journal->j_running_transaction);
-
-		/*
-		 * If there is undo-protected committed data against
-		 * this buffer, then we can remove it now.  If it is a
-		 * buffer needing such protection, the old frozen_data
-		 * field now points to a committed version of the
-		 * buffer, so rotate that field to the new committed
-		 * data.
-		 *
-		 * Otherwise, we can just throw away the frozen data now.
-		 */
-		if (jh->b_committed_data) {
-			jbd_free(jh->b_committed_data, bh->b_size);
-			jh->b_committed_data = NULL;
-			if (jh->b_frozen_data) {
-				jh->b_committed_data = jh->b_frozen_data;
-				jh->b_frozen_data = NULL;
-			}
-		} else if (jh->b_frozen_data) {
-			jbd_free(jh->b_frozen_data, bh->b_size);
-			jh->b_frozen_data = NULL;
-		}
-
-		spin_lock(&journal->j_list_lock);
-		cp_transaction = jh->b_cp_transaction;
-		if (cp_transaction) {
-			JBUFFER_TRACE(jh, "remove from old cp transaction");
-			__journal_remove_checkpoint(jh);
-		}
-
-		/* Only re-checkpoint the buffer_head if it is marked
-		 * dirty.  If the buffer was added to the BJ_Forget list
-		 * by journal_forget, it may no longer be dirty and
-		 * there's no point in keeping a checkpoint record for
-		 * it. */
-
-		/*
-		 * A buffer which has been freed while still being journaled by
-		 * a previous transaction.
-		 */
-		if (buffer_freed(bh)) {
-			/*
-			 * If the running transaction is the one containing
-			 * "add to orphan" operation (b_next_transaction !=
-			 * NULL), we have to wait for that transaction to
-			 * commit before we can really get rid of the buffer.
-			 * So just clear b_modified to not confuse transaction
-			 * credit accounting and refile the buffer to
-			 * BJ_Forget of the running transaction. If the just
-			 * committed transaction contains "add to orphan"
-			 * operation, we can completely invalidate the buffer
-			 * now. We are rather throughout in that since the
-			 * buffer may be still accessible when blocksize <
-			 * pagesize and it is attached to the last partial
-			 * page.
-			 */
-			jh->b_modified = 0;
-			if (!jh->b_next_transaction) {
-				clear_buffer_freed(bh);
-				clear_buffer_jbddirty(bh);
-				clear_buffer_mapped(bh);
-				clear_buffer_new(bh);
-				clear_buffer_req(bh);
-				bh->b_bdev = NULL;
-			}
-		}
-
-		if (buffer_jbddirty(bh)) {
-			JBUFFER_TRACE(jh, "add to new checkpointing trans");
-			__journal_insert_checkpoint(jh, commit_transaction);
-			if (is_journal_aborted(journal))
-				clear_buffer_jbddirty(bh);
-		} else {
-			J_ASSERT_BH(bh, !buffer_dirty(bh));
-			/*
-			 * The buffer on BJ_Forget list and not jbddirty means
-			 * it has been freed by this transaction and hence it
-			 * could not have been reallocated until this
-			 * transaction has committed. *BUT* it could be
-			 * reallocated once we have written all the data to
-			 * disk and before we process the buffer on BJ_Forget
-			 * list.
-			 */
-			if (!jh->b_next_transaction)
-				try_to_free = 1;
-		}
-		JBUFFER_TRACE(jh, "refile or unfile freed buffer");
-		__journal_refile_buffer(jh);
-		jbd_unlock_bh_state(bh);
-		if (try_to_free)
-			release_buffer_page(bh);
-		else
-			__brelse(bh);
-		cond_resched_lock(&journal->j_list_lock);
-	}
-	spin_unlock(&journal->j_list_lock);
-	/*
-	 * This is a bit sleazy.  We use j_list_lock to protect transition
-	 * of a transaction into T_FINISHED state and calling
-	 * __journal_drop_transaction(). Otherwise we could race with
-	 * other checkpointing code processing the transaction...
-	 */
-	spin_lock(&journal->j_state_lock);
-	spin_lock(&journal->j_list_lock);
-	/*
-	 * Now recheck if some buffers did not get attached to the transaction
-	 * while the lock was dropped...
-	 */
-	if (commit_transaction->t_forget) {
-		spin_unlock(&journal->j_list_lock);
-		spin_unlock(&journal->j_state_lock);
-		goto restart_loop;
-	}
-
-	/* Done with this transaction! */
-
-	jbd_debug(3, "JBD: commit phase 8\n");
-
-	J_ASSERT(commit_transaction->t_state == T_COMMIT_RECORD);
-
-	commit_transaction->t_state = T_FINISHED;
-	J_ASSERT(commit_transaction == journal->j_committing_transaction);
-	journal->j_commit_sequence = commit_transaction->t_tid;
-	journal->j_committing_transaction = NULL;
-	commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
-
-	/*
-	 * weight the commit time higher than the average time so we don't
-	 * react too strongly to vast changes in commit time
-	 */
-	if (likely(journal->j_average_commit_time))
-		journal->j_average_commit_time = (commit_time*3 +
-				journal->j_average_commit_time) / 4;
-	else
-		journal->j_average_commit_time = commit_time;
-
-	spin_unlock(&journal->j_state_lock);
-
-	if (commit_transaction->t_checkpoint_list == NULL &&
-	    commit_transaction->t_checkpoint_io_list == NULL) {
-		__journal_drop_transaction(journal, commit_transaction);
-	} else {
-		if (journal->j_checkpoint_transactions == NULL) {
-			journal->j_checkpoint_transactions = commit_transaction;
-			commit_transaction->t_cpnext = commit_transaction;
-			commit_transaction->t_cpprev = commit_transaction;
-		} else {
-			commit_transaction->t_cpnext =
-				journal->j_checkpoint_transactions;
-			commit_transaction->t_cpprev =
-				commit_transaction->t_cpnext->t_cpprev;
-			commit_transaction->t_cpnext->t_cpprev =
-				commit_transaction;
-			commit_transaction->t_cpprev->t_cpnext =
-				commit_transaction;
-		}
-	}
-	spin_unlock(&journal->j_list_lock);
-
-	trace_jbd_end_commit(journal, commit_transaction);
-	jbd_debug(1, "JBD: commit %d complete, head %d\n",
-		  journal->j_commit_sequence, journal->j_tail_sequence);
-
-	wake_up(&journal->j_wait_done_commit);
-}