xfs: add a lock class for group/project dquots
We can have both a user and a group/project dquot locked at the same time,
as long as the user dquot is locked first. Tell lockdep about that fact
by making the group/project dquots a different lock class.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/quota/xfs_dquot.c b/fs/xfs/quota/xfs_dquot.c
index 36d1bb6..f0bc784 100644
--- a/fs/xfs/quota/xfs_dquot.c
+++ b/fs/xfs/quota/xfs_dquot.c
@@ -73,6 +73,8 @@
int xfs_dqerror_mod = 33;
#endif
+static struct lock_class_key xfs_dquot_other_class;
+
/*
* Allocate and initialize a dquot. We don't always allocate fresh memory;
* we try to reclaim a free dquot if the number of incore dquots are above
@@ -139,7 +141,15 @@
ASSERT(dqp->q_trace);
xfs_dqtrace_entry(dqp, "DQRECLAIMED_INIT");
#endif
- }
+ }
+
+ /*
+ * In either case we need to make sure group quotas have a different
+ * lock class than user quotas, to make sure lockdep knows we can
+ * locks of one of each at the same time.
+ */
+ if (!(type & XFS_DQ_USER))
+ lockdep_set_class(&dqp->q_qlock, &xfs_dquot_other_class);
/*
* log item gets initialized later