btrfs: let can_allocate_chunk return error

For the later patch, convert the return type from bool to int and return
errors. No functional changes.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent-tree.c

@@ -3965,12 +3965,12 @@ static void found_extent(struct find_free_extent_ctl *ffe_ctl,
 	}
 }
 
-static bool can_allocate_chunk(struct btrfs_fs_info *fs_info,
+static int can_allocate_chunk(struct btrfs_fs_info *fs_info,
 			      struct find_free_extent_ctl *ffe_ctl)
 {
 	switch (ffe_ctl->policy) {
 	case BTRFS_EXTENT_ALLOC_CLUSTERED:
-		return true;
+		return 0;
 	case BTRFS_EXTENT_ALLOC_ZONED:
 		/*
 		 * If we have enough free space left in an already
@@ -3980,8 +3980,8 @@ static bool can_allocate_chunk(struct btrfs_fs_info *fs_info,
 		 */
 		if (ffe_ctl->max_extent_size >= ffe_ctl->min_alloc_size &&
 		    !btrfs_can_activate_zone(fs_info->fs_devices, ffe_ctl->flags))
-			return false;
-		return true;
+			return -ENOSPC;
+		return 0;
 	default:
 		BUG();
 	}
@@ -4063,8 +4063,9 @@ static int find_free_extent_update_loop(struct btrfs_fs_info *fs_info,
 			int exist = 0;
 
 			/*Check if allocation policy allows to create a new chunk */
-			if (!can_allocate_chunk(fs_info, ffe_ctl))
-				return -ENOSPC;
+			ret = can_allocate_chunk(fs_info, ffe_ctl);
+			if (ret)
+				return ret;
 
 			trans = current->journal_info;
 			if (trans)