diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e6fbbd74b716ae69da265779af5317c0057f1a18..7e607416755a880fef1a06d3a8a3482417c0b364 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3481,8 +3481,8 @@ void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 int btrfs_error_unpin_extent_range(struct btrfs_root *root,
 				   u64 start, u64 end);
-int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
-			       u64 num_bytes, u64 *actual_bytes);
+int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
+			 u64 num_bytes, u64 *actual_bytes);
 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root, u64 type);
 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 30965120772bd2d814a97d9b4758f1bc0b8cfe6c..8c63419a7f70de04d2e5fd1a51a3a0e334513918 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4121,12 +4121,6 @@ static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
 		if (ret)
 			break;
 
-		/* opt_discard */
-		if (btrfs_test_opt(root, DISCARD))
-			ret = btrfs_error_discard_extent(root, start,
-							 end + 1 - start,
-							 NULL);
-
 		clear_extent_dirty(unpin, start, end, GFP_NOFS);
 		btrfs_error_unpin_extent_range(root, start, end);
 		cond_resched();
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 222d6aea4a8a778cff8386873d8cb51ed5f86b16..a80b97100d90b3162d7d3688ed6b3c459bb56bc8 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1889,8 +1889,8 @@ static int btrfs_issue_discard(struct block_device *bdev,
 	return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
 }
 
-static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
-				u64 num_bytes, u64 *actual_bytes)
+int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
+			 u64 num_bytes, u64 *actual_bytes)
 {
 	int ret;
 	u64 discarded_bytes = 0;
@@ -5727,7 +5727,8 @@ void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
 	update_global_block_rsv(fs_info);
 }
 
-static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
+static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end,
+			      const bool return_free_space)
 {
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_block_group_cache *cache = NULL;
@@ -5751,7 +5752,8 @@ static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
 
 		if (start < cache->last_byte_to_unpin) {
 			len = min(len, cache->last_byte_to_unpin - start);
-			btrfs_add_free_space(cache, start, len);
+			if (return_free_space)
+				btrfs_add_free_space(cache, start, len);
 		}
 
 		start += len;
@@ -5815,7 +5817,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 						   end + 1 - start, NULL);
 
 		clear_extent_dirty(unpin, start, end, GFP_NOFS);
-		unpin_extent_range(root, start, end);
+		unpin_extent_range(root, start, end, true);
 		cond_resched();
 	}
 
@@ -8872,6 +8874,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 				       cache_node);
 		rb_erase(&block_group->cache_node,
 			 &info->block_group_cache_tree);
+		RB_CLEAR_NODE(&block_group->cache_node);
 		spin_unlock(&info->block_group_cache_lock);
 
 		down_write(&block_group->space_info->groups_sem);
@@ -9130,6 +9133,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 			spin_lock(&info->block_group_cache_lock);
 			rb_erase(&cache->cache_node,
 				 &info->block_group_cache_tree);
+			RB_CLEAR_NODE(&cache->cache_node);
 			spin_unlock(&info->block_group_cache_lock);
 			btrfs_put_block_group(cache);
 			goto error;
@@ -9271,6 +9275,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 		spin_lock(&root->fs_info->block_group_cache_lock);
 		rb_erase(&cache->cache_node,
 			 &root->fs_info->block_group_cache_tree);
+		RB_CLEAR_NODE(&cache->cache_node);
 		spin_unlock(&root->fs_info->block_group_cache_lock);
 		btrfs_put_block_group(cache);
 		return ret;
@@ -9690,13 +9695,7 @@ int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
 
 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
 {
-	return unpin_extent_range(root, start, end);
-}
-
-int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
-			       u64 num_bytes, u64 *actual_bytes)
-{
-	return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
+	return unpin_extent_range(root, start, end, false);
 }
 
 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 030847bf7cec803e36485e0999b7309d941877ef..d6c03f7f136b359c534668a38f9e9a72d299eb66 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -2966,8 +2966,8 @@ static int do_trimming(struct btrfs_block_group_cache *block_group,
 	spin_unlock(&block_group->lock);
 	spin_unlock(&space_info->lock);
 
-	ret = btrfs_error_discard_extent(fs_info->extent_root,
-					 start, bytes, &trimmed);
+	ret = btrfs_discard_extent(fs_info->extent_root,
+				   start, bytes, &trimmed);
 	if (!ret)
 		*total_trimmed += trimmed;
 
@@ -3185,16 +3185,18 @@ int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group,
 
 		spin_unlock(&block_group->lock);
 
+		lock_chunks(block_group->fs_info->chunk_root);
 		em_tree = &block_group->fs_info->mapping_tree.map_tree;
 		write_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, block_group->key.objectid,
 					   1);
 		BUG_ON(!em); /* logic error, can't happen */
+		/*
+		 * remove_extent_mapping() will delete us from the pinned_chunks
+		 * list, which is protected by the chunk mutex.
+		 */
 		remove_extent_mapping(em_tree, em);
 		write_unlock(&em_tree->lock);
-
-		lock_chunks(block_group->fs_info->chunk_root);
-		list_del_init(&em->list);
 		unlock_chunks(block_group->fs_info->chunk_root);
 
 		/* once for us and once for the tree */