fs: dcache scale d_unhashed

Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h
index da6061a6df4..e58b4c30e21 100644
--- a/fs/configfs/configfs_internal.h
+++ b/fs/configfs/configfs_internal.h
@@ -121,6 +121,7 @@ static inline struct config_item *configfs_get_config_item(struct dentry *dentry
         struct config_item * item = NULL;
 
         spin_lock(&dcache_lock);
+        spin_lock(&dentry->d_lock);
         if (!d_unhashed(dentry)) {
                 struct configfs_dirent * sd = dentry->d_fsdata;
                 if (sd->s_type & CONFIGFS_ITEM_LINK) {
@@ -129,6 +130,7 @@ static inline struct config_item *configfs_get_config_item(struct dentry *dentry
                 } else
                         item = config_item_get(sd->s_element);
         }
+        spin_unlock(&dentry->d_lock);
         spin_unlock(&dcache_lock);
 
         return item;