patch-2.4.15 linux/fs/jbd/commit.c

• Lines: 702
• Date: Fri Nov 9 14:25:04 2001
• Orig file: v2.4.14/linux/fs/jbd/commit.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.14/linux/fs/jbd/commit.c linux/fs/jbd/commit.c
@@ -0,0 +1,701 @@
+/*
+ * linux/fs/commit.c
+ *
+ * Written by Stephen C. Tweedie <sct@redhat.com>, 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/sched.h>
+#include <linux/fs.h>
+#include <linux/jbd.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/locks.h>
+#include <linux/smp_lock.h>
+
+extern spinlock_t journal_datalist_lock;
+
+/*
+ * 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, "");
+	mark_buffer_uptodate(bh, uptodate);
+	unlock_buffer(bh);
+}
+
+/*
+ * 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 journal_head *next_jh, *last_jh;
+	struct buffer_head *wbuf[64];
+	int bufs;
+	int flags;
+	int blocknr;
+	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;
+
+	/*
+	 * First job: lock down the current transaction and wait for
+	 * all outstanding updates to complete.
+	 */
+
+	lock_journal(journal); /* Protect journal->j_running_transaction */
+
+#ifdef COMMIT_STATS
+	spin_lock(&journal_datalist_lock);
+	summarise_journal_usage(journal);
+	spin_unlock(&journal_datalist_lock);
+#endif
+
+	lock_kernel();
+	
+	J_ASSERT (journal->j_running_transaction != NULL);
+	J_ASSERT (journal->j_committing_transaction == NULL);
+
+	commit_transaction = journal->j_running_transaction;
+	J_ASSERT (commit_transaction->t_state == T_RUNNING);
+
+	jbd_debug (1, "JBD: starting commit of transaction %d\n",
+		   commit_transaction->t_tid);
+
+	commit_transaction->t_state = T_LOCKED;
+	while (commit_transaction->t_updates != 0) {
+		unlock_journal(journal);
+		sleep_on(&journal->j_wait_updates);
+		lock_journal(journal);
+	}
+
+	J_ASSERT (commit_transaction->t_outstanding_credits <=
+			journal->j_max_transaction_buffers);
+
+	/* 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");
+		journal_update_superblock(journal, 1);
+	} else {
+		jbd_debug(3, "superblock not updated\n");
+	}
+
+	/*
+	 * 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 permissable.
+	 */
+
+	while (commit_transaction->t_reserved_list) {
+		jh = commit_transaction->t_reserved_list;
+		JBUFFER_TRACE(jh, "reserved, unused: refile");
+		journal_refile_buffer(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_datalist_lock);
+	__journal_clean_checkpoint_list(journal);
+	spin_unlock(&journal_datalist_lock);
+
+	/* First part of the commit: force the revoke list out to disk.
+	 * The revoke code generates its own metadata blocks on disk for this.
+	 *
+	 * It is important that we do this while the transaction is
+	 * still locked.  Generating the revoke records should not
+	 * generate any IO stalls, so this should be quick; and doing
+	 * the work while we have the transaction locked means that we
+	 * only ever have to maintain the revoke list for one
+	 * transaction at a time.
+	 */
+
+	jbd_debug (3, "JBD: commit phase 1\n");
+
+	journal_write_revoke_records(journal, commit_transaction);
+
+	/*
+	 * Now that we have built the revoke records, we can start
+	 * reusing the revoke list for a new running transaction.  We
+	 * can now safely start committing the old transaction: time to
+	 * get a new running transaction for incoming filesystem updates
+	 */
+
+	commit_transaction->t_state = T_FLUSH;
+
+	wake_up(&journal->j_wait_transaction_locked);
+
+	journal->j_committing_transaction = commit_transaction;
+	journal->j_running_transaction = NULL;
+
+	commit_transaction->t_log_start = journal->j_head;
+
+	unlock_kernel();
+	
+	jbd_debug (3, "JBD: commit phase 2\n");
+
+	/*
+	 * Now start flushing things to disk, in the order they appear
+	 * on the transaction lists.  Data blocks go first.
+	 */
+
+	/*
+	 * Whenever we unlock the journal and sleep, things can get added
+	 * onto ->t_datalist, so we have to keep looping back to write_out_data
+	 * until we *know* that the list is empty.
+	 */
+write_out_data:
+
+	/*
+	 * Cleanup any flushed data buffers from the data list.  Even in
+	 * abort mode, we want to flush this out as soon as possible.
+	 *
+	 * We take journal_datalist_lock to protect the lists from
+	 * journal_try_to_free_buffers().
+	 */
+	spin_lock(&journal_datalist_lock);
+
+write_out_data_locked:
+	bufs = 0;
+	next_jh = commit_transaction->t_sync_datalist;
+	if (next_jh == NULL)
+		goto sync_datalist_empty;
+	last_jh = next_jh->b_tprev;
+
+	do {
+		struct buffer_head *bh;
+
+		jh = next_jh;
+		next_jh = jh->b_tnext;
+		bh = jh2bh(jh);
+		if (!buffer_locked(bh)) {
+			if (buffer_dirty(bh)) {
+				BUFFER_TRACE(bh, "start journal writeout");
+				atomic_inc(&bh->b_count);
+				wbuf[bufs++] = bh;
+			} else {
+				BUFFER_TRACE(bh, "writeout complete: unfile");
+				__journal_unfile_buffer(jh);
+				jh->b_transaction = NULL;
+				__journal_remove_journal_head(bh);
+				refile_buffer(bh);
+				__brelse(bh);
+			}
+		}
+		if (bufs == ARRAY_SIZE(wbuf)) {
+			/*
+			 * Major speedup: start here on the next scan
+			 */
+			J_ASSERT(commit_transaction->t_sync_datalist != 0);
+			commit_transaction->t_sync_datalist = jh;
+			break;
+		}
+	} while (jh != last_jh);
+
+	if (bufs || current->need_resched) {
+		jbd_debug(2, "submit %d writes\n", bufs);
+		spin_unlock(&journal_datalist_lock);
+		unlock_journal(journal);
+		if (bufs)
+			ll_rw_block(WRITE, bufs, wbuf);
+		if (current->need_resched)
+			schedule();
+		journal_brelse_array(wbuf, bufs);
+		lock_journal(journal);
+		spin_lock(&journal_datalist_lock);
+		if (bufs)
+			goto write_out_data_locked;
+	}
+
+	/*
+	 * Wait for all previously submitted IO on the data list to complete.
+	 */
+	jh = commit_transaction->t_sync_datalist;
+	if (jh == NULL)
+		goto sync_datalist_empty;
+
+	do {
+		struct buffer_head *bh;
+		jh = jh->b_tprev;	/* Wait on the last written */
+		bh = jh2bh(jh);
+		if (buffer_locked(bh)) {
+			spin_unlock(&journal_datalist_lock);
+			unlock_journal(journal);
+			wait_on_buffer(bh);
+			/* the journal_head may have been removed now */
+			lock_journal(journal);
+			goto write_out_data;
+		} else if (buffer_dirty(bh)) {
+			goto write_out_data_locked;
+		}
+	} while (jh != commit_transaction->t_sync_datalist);
+	goto write_out_data_locked;
+
+sync_datalist_empty:
+	/*
+	 * Wait for all the async writepage data.  As they become unlocked
+	 * in end_buffer_io_async(), the only place where they can be
+	 * reaped is in try_to_free_buffers(), and we're locked against
+	 * that.
+	 */
+	while ((jh = commit_transaction->t_async_datalist)) {
+		struct buffer_head *bh = jh2bh(jh);
+		if (buffer_locked(bh)) {
+			spin_unlock(&journal_datalist_lock);
+			unlock_journal(journal);
+			wait_on_buffer(bh);
+			lock_journal(journal);
+			spin_lock(&journal_datalist_lock);
+			continue;	/* List may have changed */
+		}
+		if (jh->b_next_transaction) {
+			/*
+			 * For writepage() buffers in journalled data mode: a
+			 * later transaction may want the buffer for "metadata"
+			 */
+			__journal_refile_buffer(jh);
+		} else {
+			BUFFER_TRACE(bh, "finished async writeout: unfile");
+			__journal_unfile_buffer(jh);
+			jh->b_transaction = NULL;
+			__journal_remove_journal_head(bh);
+			BUFFER_TRACE(bh, "finished async writeout: refile");
+			/* It can sometimes be on BUF_LOCKED due to migration
+			 * from syncdata to asyncdata */
+			if (bh->b_list != BUF_CLEAN)
+				refile_buffer(bh);
+			__brelse(bh);
+		}
+	}
+	spin_unlock(&journal_datalist_lock);
+
+	/*
+	 * 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);
+	J_ASSERT (commit_transaction->t_async_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:
+	 */
+	commit_transaction->t_state = T_COMMIT;
+
+	descriptor = 0;
+	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 for background writing. */
+
+		if (is_journal_aborted(journal)) {
+			JBUFFER_TRACE(jh, "journal is aborting: refile");
+			journal_refile_buffer(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);
+			bh = jh2bh(descriptor);
+			jbd_debug(4, "JBD: got buffer %ld (%p)\n",
+				bh->b_blocknr, bh->b_data);
+			header = (journal_header_t *)&bh->b_data[0];
+			header->h_magic     = htonl(JFS_MAGIC_NUMBER);
+			header->h_blocktype = htonl(JFS_DESCRIPTOR_BLOCK);
+			header->h_sequence  = htonl(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_bit(BH_JWrite, &bh->b_state);
+			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? */
+
+		blocknr = journal_next_log_block(journal);
+
+		/* 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. */
+		atomic_inc(&jh2bh(jh)->b_count);
+
+		/* 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_bit(BH_JWrite, &jh2bh(jh)->b_state);
+		/*
+		 * 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_bit(BH_JWrite, &jh2bh(new_jh)->b_state);
+		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 = htonl(jh2bh(jh)->b_blocknr);
+		tag->t_flags = htonl(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 == ARRAY_SIZE(wbuf) ||
+		    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 |= htonl(JFS_FLAG_LAST_TAG);
+
+start_journal_io:
+			unlock_journal(journal);
+			for (i=0; i<bufs; i++) {
+				struct buffer_head *bh = wbuf[i];
+				set_bit(BH_Lock, &bh->b_state);
+				clear_bit(BH_Dirty, &bh->b_state);
+				bh->b_end_io = journal_end_buffer_io_sync;
+				submit_bh(WRITE, bh);
+			}
+			if (current->need_resched)
+				schedule();
+			lock_journal(journal);
+
+			/* Force a new descriptor to be generated next
+                           time round the loop. */
+			descriptor = NULL;
+			bufs = 0;
+		}
+	}
+
+	/* 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 transactions 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 journal_datalist_lock is not needed */
+ 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)) {
+			unlock_journal(journal);
+			wait_on_buffer(bh);
+			lock_journal(journal);
+			goto wait_for_iobuf;
+		}
+
+		clear_bit(BH_JWrite, &jh2bh(jh)->b_state);
+
+		JBUFFER_TRACE(jh, "ph4: unfile after journal write");
+		journal_unfile_buffer(jh);
+
+		/*
+		 * akpm: don't put back a buffer_head with stale pointers
+		 * dangling around.
+		 */
+		J_ASSERT_JH(jh, jh->b_transaction != NULL);
+		jh->b_transaction = NULL;
+
+		/*
+		 * ->t_iobuf_list should contain only dummy buffer_heads
+		 * which were created by journal_write_metadata_buffer().
+		 */
+		bh = jh2bh(jh);
+		BUFFER_TRACE(bh, "dumping temporary bh");
+		journal_unlock_journal_head(jh);
+		__brelse(bh);
+		J_ASSERT_BH(bh, atomic_read(&bh->b_count) == 0);
+		put_unused_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_bit(BH_JWrite, &bh->b_state);
+		J_ASSERT_BH(bh, buffer_jdirty(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 */
+		wake_up(&bh->b_wait);
+		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)) {
+			unlock_journal(journal);
+			wait_on_buffer(bh);
+			lock_journal(journal);
+			goto wait_for_ctlbuf;
+		}
+
+		BUFFER_TRACE(bh, "ph5: control buffer writeout done: unfile");
+		clear_bit(BH_JWrite, &bh->b_state);
+		journal_unfile_buffer(jh);
+		jh->b_transaction = NULL;
+		journal_unlock_journal_head(jh);
+		__brelse(bh);		/* One for getblk */
+		/* AKPM: bforget here */
+	}
+
+	jbd_debug(3, "JBD: commit phase 6\n");
+
+	/* 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. */
+
+	if (is_journal_aborted(journal))
+		goto skip_commit;
+
+	descriptor = journal_get_descriptor_buffer(journal);
+
+	/* AKPM: buglet - add `i' to tmp! */
+	for (i = 0; i < jh2bh(descriptor)->b_size; i += 512) {
+		journal_header_t *tmp =
+			(journal_header_t*)jh2bh(descriptor)->b_data;
+		tmp->h_magic = htonl(JFS_MAGIC_NUMBER);
+		tmp->h_blocktype = htonl(JFS_COMMIT_BLOCK);
+		tmp->h_sequence = htonl(commit_transaction->t_tid);
+	}
+
+	unlock_journal(journal);
+	JBUFFER_TRACE(descriptor, "write commit block");
+	{
+		struct buffer_head *bh = jh2bh(descriptor);
+		ll_rw_block(WRITE, 1, &bh);
+		wait_on_buffer(bh);
+		__brelse(bh);		/* One for getblk() */
+		journal_unlock_journal_head(descriptor);
+	}
+	lock_journal(journal);
+
+	/* 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. */
+
+skip_commit:
+
+	jbd_debug(3, "JBD: commit phase 7\n");
+
+	J_ASSERT(commit_transaction->t_sync_datalist == NULL);
+	J_ASSERT(commit_transaction->t_async_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);
+
+	while (commit_transaction->t_forget) {
+		transaction_t *cp_transaction;
+		struct buffer_head *bh;
+
+		jh = commit_transaction->t_forget;
+		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) {
+			kfree(jh->b_committed_data);
+			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) {
+			kfree(jh->b_frozen_data);
+			jh->b_frozen_data = NULL;
+		}
+
+		spin_lock(&journal_datalist_lock);
+		cp_transaction = jh->b_cp_transaction;
+		if (cp_transaction) {
+			JBUFFER_TRACE(jh, "remove from old cp transaction");
+			J_ASSERT_JH(jh, commit_transaction != 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. */
+		bh = jh2bh(jh);
+		if (buffer_jdirty(bh)) {
+			JBUFFER_TRACE(jh, "add to new checkpointing trans");
+			__journal_insert_checkpoint(jh, commit_transaction);
+			JBUFFER_TRACE(jh, "refile for checkpoint writeback");
+			__journal_refile_buffer(jh);
+		} else {
+			J_ASSERT_BH(bh, !buffer_dirty(bh));
+			J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
+			__journal_unfile_buffer(jh);
+			jh->b_transaction = 0;
+			__journal_remove_journal_head(bh);
+			__brelse(bh);
+		}
+		spin_unlock(&journal_datalist_lock);
+	}
+
+	/* Done with this transaction! */
+
+	jbd_debug(3, "JBD: commit phase 8\n");
+
+	J_ASSERT (commit_transaction->t_state == T_COMMIT);
+	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;
+
+	spin_lock(&journal_datalist_lock);
+	if (commit_transaction->t_checkpoint_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_datalist_lock);
+
+	jbd_debug(1, "JBD: commit %d complete, head %d\n",
+		  journal->j_commit_sequence, journal->j_tail_sequence);
+
+	unlock_journal(journal);
+	wake_up(&journal->j_wait_done_commit);
+}