now lock_parent() can't run into killed dentry

all remaining callers hold either a reference or ->i_lock

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 3 insertions, 10 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index af8501489af5..916fd57b9d18 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -593,8 +593,6 @@ static inline struct dentry *lock_parent(struct dentry *dentry)
         struct dentry *parent = dentry->d_parent;
         if (IS_ROOT(dentry))
                 return NULL;
-        if (unlikely(dentry->d_lockref.count < 0))
-                return NULL;
         if (likely(spin_trylock(&parent->d_lock)))
                 return parent;
         rcu_read_lock();
@@ -614,16 +612,11 @@ again:
                 spin_unlock(&parent->d_lock);
                 goto again;
         }
-        if (parent != dentry) {
+        rcu_read_unlock();
+        if (parent != dentry)
                 spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
-                if (unlikely(dentry->d_lockref.count < 0)) {
-                        spin_unlock(&parent->d_lock);
-                        parent = NULL;
-                }
-        } else {
+        else
                 parent = NULL;
-        }
-        rcu_read_unlock();
         return parent;
 }