Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
 "I'm not proud of how long it took me to track down that one liner in
  btrfs_sync_log(), but the good news is the patches I was trying to
  blame for these problems were actually fine (sorry Filipe)"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: introduce tickets_id to determine whether asynchronous metadata reclaim work makes progress
  btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns
  btrfs: do not decrease bytes_may_use when replaying extents

Author: torvalds

fs/btrfs/ctree.h

@@ -427,6 +427,7 @@ struct btrfs_space_info {
 	struct list_head ro_bgs;
 	struct list_head priority_tickets;
 	struct list_head tickets;
+	u64 tickets_id;
 
 	struct rw_semaphore groups_sem;
 	/* for block groups in our same type */

fs/btrfs/extent-tree.c

@@ -4966,12 +4966,12 @@ static void wake_all_tickets(struct list_head *head)
  */
 static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
 {
-	struct reserve_ticket *last_ticket = NULL;
 	struct btrfs_fs_info *fs_info;
 	struct btrfs_space_info *space_info;
 	u64 to_reclaim;
 	int flush_state;
 	int commit_cycles = 0;
+	u64 last_tickets_id;
 
 	fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
 	space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
@@ -4984,8 +4984,7 @@ static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
 		spin_unlock(&space_info->lock);
 		return;
 	}
-	last_ticket = list_first_entry(&space_info->tickets,
-				       struct reserve_ticket, list);
+	last_tickets_id = space_info->tickets_id;
 	spin_unlock(&space_info->lock);
 
 	flush_state = FLUSH_DELAYED_ITEMS_NR;
@@ -5005,10 +5004,10 @@ static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
 							      space_info);
 		ticket = list_first_entry(&space_info->tickets,
 					  struct reserve_ticket, list);
-		if (last_ticket == ticket) {
+		if (last_tickets_id == space_info->tickets_id) {
 			flush_state++;
 		} else {
-			last_ticket = ticket;
+			last_tickets_id = space_info->tickets_id;
 			flush_state = FLUSH_DELAYED_ITEMS_NR;
 			if (commit_cycles)
 				commit_cycles--;
@@ -5384,6 +5383,7 @@ static void space_info_add_old_bytes(struct btrfs_fs_info *fs_info,
 			list_del_init(&ticket->list);
 			num_bytes -= ticket->bytes;
 			ticket->bytes = 0;
+			space_info->tickets_id++;
 			wake_up(&ticket->wait);
 		} else {
 			ticket->bytes -= num_bytes;
@@ -5426,6 +5426,7 @@ static void space_info_add_new_bytes(struct btrfs_fs_info *fs_info,
 			num_bytes -= ticket->bytes;
 			space_info->bytes_may_use += ticket->bytes;
 			ticket->bytes = 0;
+			space_info->tickets_id++;
 			wake_up(&ticket->wait);
 		} else {
 			trace_btrfs_space_reservation(fs_info, "space_info",
@@ -8216,6 +8217,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 {
 	int ret;
 	struct btrfs_block_group_cache *block_group;
+	struct btrfs_space_info *space_info;
 
 	/*
 	 * Mixed block groups will exclude before processing the log so we only
@@ -8231,9 +8233,14 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 	if (!block_group)
 		return -EINVAL;
 
-	ret = btrfs_add_reserved_bytes(block_group, ins->offset,
-				       ins->offset, 0);
-	BUG_ON(ret); /* logic error */
+	space_info = block_group->space_info;
+	spin_lock(&space_info->lock);
+	spin_lock(&block_group->lock);
+	space_info->bytes_reserved += ins->offset;
+	block_group->reserved += ins->offset;
+	spin_unlock(&block_group->lock);
+	spin_unlock(&space_info->lock);
+
 	ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
 					 0, owner, offset, ins, 1);
 	btrfs_put_block_group(block_group);

fs/btrfs/tree-log.c

@@ -2867,6 +2867,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 
 	if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) {
 		blk_finish_plug(&plug);
+		list_del_init(&root_log_ctx.list);
 		mutex_unlock(&log_root_tree->log_mutex);
 		ret = root_log_ctx.log_ret;
 		goto out;