2 files changed, 24 insertions, 14 deletions

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index a540ace3e03a..63be7d01a9a3 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -735,11 +735,16 @@ static noinline void update_existing_head_ref(struct btrfs_trans_handle *trans,
 	 * 2. We were negative and went to 0 or positive, so no longer can say
 	 *    that the space would be pinned, decrement our counter from the
 	 *    total_bytes_pinned counter.
+	 * 3. We are now at 0 and have ->must_insert_reserved set, which means
+	 *    this was a new allocation and then we dropped it, and thus must
+	 *    add our space to the total_bytes_pinned counter.
 	 */
 	if (existing->total_ref_mod < 0 && old_ref_mod >= 0)
 		btrfs_mod_total_bytes_pinned(fs_info, flags, existing->num_bytes);
 	else if (existing->total_ref_mod >= 0 && old_ref_mod < 0)
 		btrfs_mod_total_bytes_pinned(fs_info, flags, -existing->num_bytes);
+	else if (existing->total_ref_mod == 0 && existing->must_insert_reserved)
+		btrfs_mod_total_bytes_pinned(fs_info, flags, existing->num_bytes);
 
 	spin_unlock(&existing->lock);
 }
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2f591036ffc1..6f0c59debc2b 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1754,23 +1754,28 @@ void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
 {
 	int nr_items = 1;	/* Dropping this ref head update. */
 
-	if (head->total_ref_mod < 0) {
+	/*
+	 * We had csum deletions accounted for in our delayed refs rsv, we need
+	 * to drop the csum leaves for this update from our delayed_refs_rsv.
+	 */
+	if (head->total_ref_mod < 0 && head->is_data) {
+		spin_lock(&delayed_refs->lock);
+		delayed_refs->pending_csums -= head->num_bytes;
+		spin_unlock(&delayed_refs->lock);
+		nr_items += btrfs_csum_bytes_to_leaves(fs_info, head->num_bytes);
+	}
+
+	/*
+	 * We were dropping refs, or had a new ref and dropped it, and thus must
+	 * adjust down our total_bytes_pinned, the space may or may not have
+	 * been pinned and so is accounted for properly in the pinned space by
+	 * now.
+	 */
+	if (head->total_ref_mod < 0 ||
+	    (head->total_ref_mod == 0 && head->must_insert_reserved)) {
 		u64 flags = btrfs_ref_head_to_space_flags(head);
 
 		btrfs_mod_total_bytes_pinned(fs_info, flags, -head->num_bytes);
-
-		/*
-		 * We had csum deletions accounted for in our delayed refs rsv,
-		 * we need to drop the csum leaves for this update from our
-		 * delayed_refs_rsv.
-		 */
-		if (head->is_data) {
-			spin_lock(&delayed_refs->lock);
-			delayed_refs->pending_csums -= head->num_bytes;
-			spin_unlock(&delayed_refs->lock);
-			nr_items += btrfs_csum_bytes_to_leaves(fs_info,
-				head->num_bytes);
-		}
 	}
 
 	btrfs_delayed_refs_rsv_release(fs_info, nr_items);