1 files changed, 56 insertions, 124 deletions

diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index c1a7bc923cf..a8bc47f75fa 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -34,89 +34,6 @@
 
 #include <trace/events/ext4.h>
 
-static void dump_completed_IO(struct inode * inode)
-{
-#ifdef	EXT4_DEBUG
-	struct list_head *cur, *before, *after;
-	ext4_io_end_t *io, *io0, *io1;
-	unsigned long flags;
-
-	if (list_empty(&EXT4_I(inode)->i_completed_io_list)){
-		ext4_debug("inode %lu completed_io list is empty\n", inode->i_ino);
-		return;
-	}
-
-	ext4_debug("Dump inode %lu completed_io list \n", inode->i_ino);
-	spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
-	list_for_each_entry(io, &EXT4_I(inode)->i_completed_io_list, list){
-		cur = &io->list;
-		before = cur->prev;
-		io0 = container_of(before, ext4_io_end_t, list);
-		after = cur->next;
-		io1 = container_of(after, ext4_io_end_t, list);
-
-		ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n",
-			    io, inode->i_ino, io0, io1);
-	}
-	spin_unlock_irqrestore(&EXT4_I(inode)->i_completed_io_lock, flags);
-#endif
-}
-
-/*
- * This function is called from ext4_sync_file().
- *
- * When IO is completed, the work to convert unwritten extents to
- * written is queued on workqueue but may not get immediately
- * scheduled. When fsync is called, we need to ensure the
- * conversion is complete before fsync returns.
- * The inode keeps track of a list of pending/completed IO that
- * might needs to do the conversion. This function walks through
- * the list and convert the related unwritten extents for completed IO
- * to written.
- * The function return the number of pending IOs on success.
- */
-static int flush_completed_IO(struct inode *inode)
-{
-	ext4_io_end_t *io;
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	unsigned long flags;
-	int ret = 0;
-	int ret2 = 0;
-
-	if (list_empty(&ei->i_completed_io_list))
-		return ret;
-
-	dump_completed_IO(inode);
-	spin_lock_irqsave(&ei->i_completed_io_lock, flags);
-	while (!list_empty(&ei->i_completed_io_list)){
-		io = list_entry(ei->i_completed_io_list.next,
-				ext4_io_end_t, list);
-		/*
-		 * Calling ext4_end_io_nolock() to convert completed
-		 * IO to written.
-		 *
-		 * When ext4_sync_file() is called, run_queue() may already
-		 * about to flush the work corresponding to this io structure.
-		 * It will be upset if it founds the io structure related
-		 * to the work-to-be schedule is freed.
-		 *
-		 * Thus we need to keep the io structure still valid here after
-		 * convertion finished. The io structure has a flag to
-		 * avoid double converting from both fsync and background work
-		 * queue work.
-		 */
-		spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
-		ret = ext4_end_io_nolock(io);
-		spin_lock_irqsave(&ei->i_completed_io_lock, flags);
-		if (ret < 0)
-			ret2 = ret;
-		else
-			list_del_init(&io->list);
-	}
-	spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
-	return (ret2 < 0) ? ret2 : 0;
-}
-
 /*
  * If we're not journaling and this is a just-created file, we have to
  * sync our parent directory (if it was freshly created) since
@@ -125,19 +42,35 @@ static int flush_completed_IO(struct inode *inode)
  * the parent directory's parent as well, and so on recursively, if
  * they are also freshly created.
  */
-static void ext4_sync_parent(struct inode *inode)
+static int ext4_sync_parent(struct inode *inode)
 {
 	struct dentry *dentry = NULL;
+	struct inode *next;
+	int ret = 0;
 
-	while (inode && ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
+	if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY))
+		return 0;
+	inode = igrab(inode);
+	while (ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) {
 		ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY);
-		dentry = list_entry(inode->i_dentry.next,
-				    struct dentry, d_alias);
-		if (!dentry || !dentry->d_parent || !dentry->d_parent->d_inode)
+		dentry = d_find_any_alias(inode);
+		if (!dentry)
+			break;
+		next = igrab(dentry->d_parent->d_inode);
+		dput(dentry);
+		if (!next)
+			break;
+		iput(inode);
+		inode = next;
+		ret = sync_mapping_buffers(inode->i_mapping);
+		if (ret)
+			break;
+		ret = sync_inode_metadata(inode, 1);
+		if (ret)
 			break;
-		inode = dentry->d_parent->d_inode;
-		sync_mapping_buffers(inode->i_mapping);
 	}
+	iput(inode);
+	return ret;
 }
 
 /*
@@ -150,36 +83,39 @@ static void ext4_sync_parent(struct inode *inode)
  *
  * What we do is just kick off a commit and wait on it.  This will snapshot the
  * inode to disk.
- *
- * i_mutex lock is held when entering and exiting this function
  */
 
-int ext4_sync_file(struct file *file, int datasync)
+int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 {
 	struct inode *inode = file->f_mapping->host;
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
-	int ret;
+	int ret = 0, err;
 	tid_t commit_tid;
+	bool needs_barrier = false;
 
 	J_ASSERT(ext4_journal_current_handle() == NULL);
 
-	trace_ext4_sync_file(file, datasync);
+	trace_ext4_sync_file_enter(file, datasync);
 
-	if (inode->i_sb->s_flags & MS_RDONLY)
-		return 0;
-
-	ret = flush_completed_IO(inode);
-	if (ret < 0)
-		return ret;
+	if (inode->i_sb->s_flags & MS_RDONLY) {
+		/* Make sure that we read updated s_mount_flags value */
+		smp_rmb();
+		if (EXT4_SB(inode->i_sb)->s_mount_flags & EXT4_MF_FS_ABORTED)
+			ret = -EROFS;
+		goto out;
+	}
 
 	if (!journal) {
-		ret = generic_file_fsync(file, datasync);
-		if (!ret && !list_empty(&inode->i_dentry))
-			ext4_sync_parent(inode);
-		return ret;
+		ret = generic_file_fsync(file, start, end, datasync);
+		if (!ret && !hlist_empty(&inode->i_dentry))
+			ret = ext4_sync_parent(inode);
+		goto out;
 	}
 
+	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (ret)
+		return ret;
 	/*
 	 * data=writeback,ordered:
 	 *  The caller's filemap_fdatawrite()/wait will sync the data.
@@ -194,26 +130,22 @@ int ext4_sync_file(struct file *file, int datasync)
 	 *  (they were dirtied by commit).  But that's OK - the blocks are
 	 *  safe in-journal, which is all fsync() needs to ensure.
 	 */
-	if (ext4_should_journal_data(inode))
-		return ext4_force_commit(inode->i_sb);
+	if (ext4_should_journal_data(inode)) {
+		ret = ext4_force_commit(inode->i_sb);
+		goto out;
+	}
 
 	commit_tid = datasync ? ei->i_datasync_tid : ei->i_sync_tid;
-	if (jbd2_log_start_commit(journal, commit_tid)) {
-		/*
-		 * When the journal is on a different device than the
-		 * fs data disk, we need to issue the barrier in
-		 * writeback mode.  (In ordered mode, the jbd2 layer
-		 * will take care of issuing the barrier.  In
-		 * data=journal, all of the data blocks are written to
-		 * the journal device.)
-		 */
-		if (ext4_should_writeback_data(inode) &&
-		    (journal->j_fs_dev != journal->j_dev) &&
-		    (journal->j_flags & JBD2_BARRIER))
-			blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL,
-					NULL);
-		ret = jbd2_log_wait_commit(journal, commit_tid);
-	} else if (journal->j_flags & JBD2_BARRIER)
-		blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
+	if (journal->j_flags & JBD2_BARRIER &&
+	    !jbd2_trans_will_send_data_barrier(journal, commit_tid))
+		needs_barrier = true;
+	ret = jbd2_complete_transaction(journal, commit_tid);
+	if (needs_barrier) {
+		err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
+		if (!ret)
+			ret = err;
+	}
+out:
+	trace_ext4_sync_file_exit(inode, ret);
 	return ret;
 }