Merge branch 'for-linus' into for-linus-3.12

fs/btrfs/async-thread.c

@@ -107,7 +107,8 @@ static void check_idle_worker(struct btrfs_worker_thread *worker)
 		worker->idle = 1;
 
 		/* the list may be empty if the worker is just starting */
-		if (!list_empty(&worker->worker_list)) {
+		if (!list_empty(&worker->worker_list) &&
+		    !worker->workers->stopping) {
 			list_move(&worker->worker_list,
 				 &worker->workers->idle_list);
 		}
@@ -127,7 +128,8 @@ static void check_busy_worker(struct btrfs_worker_thread *worker)
 		spin_lock_irqsave(&worker->workers->lock, flags);
 		worker->idle = 0;
 
-		if (!list_empty(&worker->worker_list)) {
+		if (!list_empty(&worker->worker_list) &&
+		    !worker->workers->stopping) {
 			list_move_tail(&worker->worker_list,
 				      &worker->workers->worker_list);
 		}
@@ -412,6 +414,7 @@ void btrfs_stop_workers(struct btrfs_workers *workers)
 	int can_stop;
 
 	spin_lock_irq(&workers->lock);
+	workers->stopping = 1;
 	list_splice_init(&workers->idle_list, &workers->worker_list);
 	while (!list_empty(&workers->worker_list)) {
 		cur = workers->worker_list.next;
@@ -455,6 +458,7 @@ void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max,
 	workers->ordered = 0;
 	workers->atomic_start_pending = 0;
 	workers->atomic_worker_start = async_helper;
+	workers->stopping = 0;
 }
 
 /*
@@ -480,15 +484,19 @@ static int __btrfs_start_workers(struct btrfs_workers *workers)
 	atomic_set(&worker->num_pending, 0);
 	atomic_set(&worker->refs, 1);
 	worker->workers = workers;
-	worker->task = kthread_run(worker_loop, worker,
+	worker->task = kthread_create(worker_loop, worker,
 				      "btrfs-%s-%d", workers->name,
 				      workers->num_workers + 1);
 	if (IS_ERR(worker->task)) {
 		ret = PTR_ERR(worker->task);
-		kfree(worker);
 		goto fail;
 	}
+
 	spin_lock_irq(&workers->lock);
+	if (workers->stopping) {
+		spin_unlock_irq(&workers->lock);
+		goto fail_kthread;
+	}
 	list_add_tail(&worker->worker_list, &workers->idle_list);
 	worker->idle = 1;
 	workers->num_workers++;
@@ -496,8 +504,13 @@ static int __btrfs_start_workers(struct btrfs_workers *workers)
 	WARN_ON(workers->num_workers_starting < 0);
 	spin_unlock_irq(&workers->lock);
 
+	wake_up_process(worker->task);
 	return 0;
+
+fail_kthread:
+	kthread_stop(worker->task);
 fail:
+	kfree(worker);
 	spin_lock_irq(&workers->lock);
 	workers->num_workers_starting--;
 	spin_unlock_irq(&workers->lock);

fs/btrfs/async-thread.h

@@ -107,6 +107,8 @@ struct btrfs_workers {
 
 	/* extra name for this worker, used for current->name */
 	char *name;
+
+	int stopping;
 };
 
 void btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work);

fs/btrfs/dev-replace.c

@@ -535,10 +535,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
 	list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
 
 	btrfs_rm_dev_replace_srcdev(fs_info, src_device);
-	if (src_device->bdev) {
-		/* zero out the old super */
-		btrfs_scratch_superblock(src_device);
-	}
+
 	/*
 	 * this is again a consistent state where no dev_replace procedure
 	 * is running, the target device is part of the filesystem, the

fs/btrfs/extent_io.c

@@ -1614,7 +1614,7 @@ static noinline u64 find_lock_delalloc_range(struct inode *inode,
 		*start = delalloc_start;
 		*end = delalloc_end;
 		free_extent_state(cached_state);
-		return found;
+		return 0;
 	}
 
 	/*

fs/btrfs/transaction.c

@@ -1838,11 +1838,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 	assert_qgroups_uptodate(trans);
 	update_super_roots(root);
 
-	if (!root->fs_info->log_root_recovering) {
 	btrfs_set_super_log_root(root->fs_info->super_copy, 0);
 	btrfs_set_super_log_root_level(root->fs_info->super_copy, 0);
-	}
-
 	memcpy(root->fs_info->super_for_commit, root->fs_info->super_copy,
 	       sizeof(*root->fs_info->super_copy));
 

fs/btrfs/volumes.c

@@ -1716,6 +1716,7 @@ void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info,
 				 struct btrfs_device *srcdev)
 {
 	WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
+
 	list_del_rcu(&srcdev->dev_list);
 	list_del_rcu(&srcdev->dev_alloc_list);
 	fs_info->fs_devices->num_devices--;
@@ -1725,9 +1726,13 @@ void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info,
 	}
 	if (srcdev->can_discard)
 		fs_info->fs_devices->num_can_discard--;
-	if (srcdev->bdev)
+	if (srcdev->bdev) {
 		fs_info->fs_devices->open_devices--;
 
+		/* zero out the old super */
+		btrfs_scratch_superblock(srcdev);
+	}
+
 	call_rcu(&srcdev->rcu, free_device);
 }