Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs updates from Chris Mason:
 "I've been running these through a longer set of load tests because my
  commits change the free space cache writeout.  It fixes commit stalls
  on large filesystems (~20T space used and up) that we have been
  triggering here.  We were seeing new writers blocked for 10 seconds or
  more during commits, which is far from good.

  Josef and I fixed up ENOSPC aborts when deleting huge files (3T or
  more), that are triggered because our metadata reservations were not
  properly accounting for crcs and were not replenishing during the
  truncate.

  Also in this series, a number of qgroup fixes from Fujitsu and Dave
  Sterba collected most of the pending cleanups from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (93 commits)
  btrfs: quota: Update quota tree after qgroup relationship change.
  btrfs: quota: Automatically update related qgroups or mark INCONSISTENT flags when assigning/deleting a qgroup relations.
  btrfs: qgroup: clear STATUS_FLAG_ON in disabling quota.
  btrfs: Update btrfs qgroup status item when rescan is done.
  btrfs: qgroup: Fix dead judgement on qgroup_rescan_leaf() return value.
  btrfs: Don't allow subvolid >= (1 << BTRFS_QGROUP_LEVEL_SHIFT) to be created
  btrfs: Check qgroup level in kernel qgroup assign.
  btrfs: qgroup: allow to remove qgroup which has parent but no child.
  btrfs: qgroup: return EINVAL if level of parent is not higher than child's.
  btrfs: qgroup: do a reservation in a higher level.
  Btrfs: qgroup, Account data space in more proper timings.
  Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.
  Btrfs: qgroup: free reserved in exceeding quota.
  Btrfs: qgroup: cleanup, remove an unsued parameter in btrfs_create_qgroup().
  btrfs: qgroup: fix limit args override whole limit struct
  btrfs: qgroup: update limit info in function btrfs_run_qgroups().
  btrfs: qgroup: consolidate the parameter of fucntion update_qgroup_limit_item().
  btrfs: qgroup: update qgroup in memory at the same time when we update it in btree.
  btrfs: qgroup: inherit limit info from srcgroup in creating snapshot.
  btrfs: Support busy loop of write and delete
  ...

1 files changed, 20 insertions, 2 deletions

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 6d16bea94e1c..8f8ed7d20bac 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -489,11 +489,13 @@ update_existing_ref(struct btrfs_trans_handle *trans,
  * existing and update must have the same bytenr
  */
 static noinline void
-update_existing_head_ref(struct btrfs_delayed_ref_node *existing,
+update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
+			 struct btrfs_delayed_ref_node *existing,
 			 struct btrfs_delayed_ref_node *update)
 {
 	struct btrfs_delayed_ref_head *existing_ref;
 	struct btrfs_delayed_ref_head *ref;
+	int old_ref_mod;
 
 	existing_ref = btrfs_delayed_node_to_head(existing);
 	ref = btrfs_delayed_node_to_head(update);
@@ -541,7 +543,20 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing,
 	 * only need the lock for this case cause we could be processing it
 	 * currently, for refs we just added we know we're a-ok.
 	 */
+	old_ref_mod = existing_ref->total_ref_mod;
 	existing->ref_mod += update->ref_mod;
+	existing_ref->total_ref_mod += update->ref_mod;
+
+	/*
+	 * If we are going to from a positive ref mod to a negative or vice
+	 * versa we need to make sure to adjust pending_csums accordingly.
+	 */
+	if (existing_ref->is_data) {
+		if (existing_ref->total_ref_mod >= 0 && old_ref_mod < 0)
+			delayed_refs->pending_csums -= existing->num_bytes;
+		if (existing_ref->total_ref_mod < 0 && old_ref_mod >= 0)
+			delayed_refs->pending_csums += existing->num_bytes;
+	}
 	spin_unlock(&existing_ref->lock);
 }
 
@@ -605,6 +620,7 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
 	head_ref->is_data = is_data;
 	head_ref->ref_root = RB_ROOT;
 	head_ref->processing = 0;
+	head_ref->total_ref_mod = count_mod;
 
 	spin_lock_init(&head_ref->lock);
 	mutex_init(&head_ref->mutex);
@@ -614,7 +630,7 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
 	existing = htree_insert(&delayed_refs->href_root,
 				&head_ref->href_node);
 	if (existing) {
-		update_existing_head_ref(&existing->node, ref);
+		update_existing_head_ref(delayed_refs, &existing->node, ref);
 		/*
 		 * we've updated the existing ref, free the newly
 		 * allocated ref
@@ -622,6 +638,8 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
 		kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
 		head_ref = existing;
 	} else {
+		if (is_data && count_mod < 0)
+			delayed_refs->pending_csums += num_bytes;
 		delayed_refs->num_heads++;
 		delayed_refs->num_heads_ready++;
 		atomic_inc(&delayed_refs->num_entries);