btrfs: Replace fs_info->flush_workers with btrfs_workqueue.

Replace the fs_info->submit_workers with the newly created
btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>

fs/btrfs/ctree.h

@@ -1507,7 +1507,7 @@ struct btrfs_fs_info {
 	struct btrfs_workers generic_worker;
 	struct btrfs_workqueue_struct *workers;
 	struct btrfs_workqueue_struct *delalloc_workers;
-	struct btrfs_workers flush_workers;
+	struct btrfs_workqueue_struct *flush_workers;
 	struct btrfs_workers endio_workers;
 	struct btrfs_workers endio_meta_workers;
 	struct btrfs_workers endio_raid56_workers;
@@ -3681,7 +3681,7 @@ struct btrfs_delalloc_work {
 	int delay_iput;
 	struct completion completion;
 	struct list_head list;
-	struct btrfs_work work;
+	struct btrfs_work_struct work;
 };
 
 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,

fs/btrfs/disk-io.c

@@ -2010,7 +2010,7 @@ static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
 	btrfs_stop_workers(&fs_info->delayed_workers);
 	btrfs_stop_workers(&fs_info->caching_workers);
 	btrfs_stop_workers(&fs_info->readahead_workers);
-	btrfs_stop_workers(&fs_info->flush_workers);
+	btrfs_destroy_workqueue(fs_info->flush_workers);
 	btrfs_stop_workers(&fs_info->qgroup_rescan_workers);
 }
 
@@ -2483,9 +2483,8 @@ int open_ctree(struct super_block *sb,
 	fs_info->delalloc_workers =
 		btrfs_alloc_workqueue("delalloc", flags, max_active, 2);
 
-	btrfs_init_workers(&fs_info->flush_workers, "flush_delalloc",
-			   fs_info->thread_pool_size, NULL);
-
+	fs_info->flush_workers =
+		btrfs_alloc_workqueue("flush_delalloc", flags, max_active, 0);
 
 	btrfs_init_workers(&fs_info->caching_workers, "cache",
 			   fs_info->thread_pool_size, NULL);
@@ -2560,14 +2559,13 @@ int open_ctree(struct super_block *sb,
 	ret |= btrfs_start_workers(&fs_info->delayed_workers);
 	ret |= btrfs_start_workers(&fs_info->caching_workers);
 	ret |= btrfs_start_workers(&fs_info->readahead_workers);
-	ret |= btrfs_start_workers(&fs_info->flush_workers);
 	ret |= btrfs_start_workers(&fs_info->qgroup_rescan_workers);
 	if (ret) {
 		err = -ENOMEM;
 		goto fail_sb_buffer;
 	}
 	if (!(fs_info->workers && fs_info->delalloc_workers &&
-	      fs_info->submit_workers)) {
+	      fs_info->submit_workers && fs_info->flush_workers)) {
 		err = -ENOMEM;
 		goto fail_sb_buffer;
 	}

fs/btrfs/inode.c

@@ -8386,7 +8386,7 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	return ret;
 }
 
-static void btrfs_run_delalloc_work(struct btrfs_work *work)
+static void btrfs_run_delalloc_work(struct btrfs_work_struct *work)
 {
 	struct btrfs_delalloc_work *delalloc_work;
 	struct inode *inode;
@@ -8424,7 +8424,7 @@ struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
 	work->inode = inode;
 	work->wait = wait;
 	work->delay_iput = delay_iput;
-	work->work.func = btrfs_run_delalloc_work;
+	btrfs_init_work(&work->work, btrfs_run_delalloc_work, NULL, NULL);
 
 	return work;
 }
@@ -8476,7 +8476,7 @@ static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
 			goto out;
 		}
 		list_add_tail(&work->list, &works);
-		btrfs_queue_worker(&root->fs_info->flush_workers,
+		btrfs_queue_work(root->fs_info->flush_workers,
 				 &work->work);
 
 		cond_resched();

fs/btrfs/ordered-data.c

@@ -576,7 +576,7 @@ void btrfs_remove_ordered_extent(struct inode *inode,
 	wake_up(&entry->wait);
 }
 
-static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
+static void btrfs_run_ordered_extent_work(struct btrfs_work_struct *work)
 {
 	struct btrfs_ordered_extent *ordered;
 
@@ -609,9 +609,10 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root, int nr)
 		atomic_inc(&ordered->refs);
 		spin_unlock(&root->ordered_extent_lock);
 
-		ordered->flush_work.func = btrfs_run_ordered_extent_work;
+		btrfs_init_work(&ordered->flush_work,
+				btrfs_run_ordered_extent_work, NULL, NULL);
 		list_add_tail(&ordered->work_list, &works);
-		btrfs_queue_worker(&root->fs_info->flush_workers,
+		btrfs_queue_work(root->fs_info->flush_workers,
 				 &ordered->flush_work);
 
 		cond_resched();
@@ -725,7 +726,7 @@ int btrfs_run_ordered_operations(struct btrfs_trans_handle *trans,
 			goto out;
 		}
 		list_add_tail(&work->list, &works);
-		btrfs_queue_worker(&root->fs_info->flush_workers,
+		btrfs_queue_work(root->fs_info->flush_workers,
 				 &work->work);
 
 		cond_resched();

fs/btrfs/ordered-data.h

@@ -133,7 +133,7 @@ struct btrfs_ordered_extent {
 	struct btrfs_work work;
 
 	struct completion completion;
-	struct btrfs_work flush_work;
+	struct btrfs_work_struct flush_work;
 	struct list_head work_list;
 };