ocfs2: Push out dropping of dentry lock to ocfs2_wq

Dropping of last reference to dentry lock is a complicated operation involving
dropping of reference to inode. This can get complicated and quota code in
particular needs to obtain some quota locks which leads to potential deadlock.
Thus we defer dropping of inode reference to ocfs2_wq.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index ad5c24a29edd..077384135f4e 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -210,6 +210,7 @@ struct ocfs2_journal;
 struct ocfs2_slot_info;
 struct ocfs2_recovery_map;
 struct ocfs2_quota_recovery;
+struct ocfs2_dentry_lock;
 struct ocfs2_super
 {
         struct task_struct *commit_task;
@@ -325,6 +326,11 @@ struct ocfs2_super
         struct list_head blocked_lock_list;
         unsigned long blocked_lock_count;
 
+        /* List of dentry locks to release. Anyone can add locks to
+         * the list, ocfs2_wq processes the list  */
+        struct ocfs2_dentry_lock *dentry_lock_list;
+        struct work_struct dentry_lock_work;
+
         wait_queue_head_t               osb_mount_event;
 
         /* Truncate log info */