1 files changed, 27 insertions, 0 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c21cd85a2e3a..c57bf387e502 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -607,6 +607,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
 				cache->cached = BTRFS_CACHE_NO;
 			} else {
 				cache->cached = BTRFS_CACHE_STARTED;
+				cache->has_caching_ctl = 1;
 			}
 		}
 		spin_unlock(&cache->lock);
@@ -627,6 +628,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
 			cache->cached = BTRFS_CACHE_NO;
 		} else {
 			cache->cached = BTRFS_CACHE_STARTED;
+			cache->has_caching_ctl = 1;
 		}
 		spin_unlock(&cache->lock);
 		wake_up(&caching_ctl->wait);
@@ -9317,6 +9319,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	int ret;
 	int index;
 	int factor;
+	struct btrfs_caching_control *caching_ctl = NULL;
 
 	root = root->fs_info->extent_root;
 
@@ -9425,8 +9428,32 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		kobject_put(kobj);
 	}
 
+	if (block_group->has_caching_ctl)
+		caching_ctl = get_caching_control(block_group);
 	if (block_group->cached == BTRFS_CACHE_STARTED)
 		wait_block_group_cache_done(block_group);
+	if (block_group->has_caching_ctl) {
+		down_write(&root->fs_info->commit_root_sem);
+		if (!caching_ctl) {
+			struct btrfs_caching_control *ctl;
+
+			list_for_each_entry(ctl,
+				    &root->fs_info->caching_block_groups, list)
+				if (ctl->block_group == block_group) {
+					caching_ctl = ctl;
+					atomic_inc(&caching_ctl->count);
+					break;
+				}
+		}
+		if (caching_ctl)
+			list_del_init(&caching_ctl->list);
+		up_write(&root->fs_info->commit_root_sem);
+		if (caching_ctl) {
+			/* Once for the caching bgs list and once for us. */
+			put_caching_control(caching_ctl);
+			put_caching_control(caching_ctl);
+		}
+	}
 
 	btrfs_remove_free_space_cache(block_group);