1 files changed, 19 insertions, 9 deletions

diff --git a/fs/dcookies.c b/fs/dcookies.c
index 855d4b1d619a..180e9fec4ad8 100644
--- a/fs/dcookies.c
+++ b/fs/dcookies.c
@@ -93,10 +93,15 @@ static struct dcookie_struct *alloc_dcookie(struct path *path)
 {
         struct dcookie_struct *dcs = kmem_cache_alloc(dcookie_cache,
                                                         GFP_KERNEL);
+        struct dentry *d;
         if (!dcs)
                 return NULL;
 
-        path->dentry->d_cookie = dcs;
+        d = path->dentry;
+        spin_lock(&d->d_lock);
+        d->d_flags |= DCACHE_COOKIE;
+        spin_unlock(&d->d_lock);
+
         dcs->path = *path;
         path_get(path);
         hash_dcookie(dcs);
@@ -119,14 +124,14 @@ int get_dcookie(struct path *path, unsigned long *cookie)
                 goto out;
         }
 
-        dcs = path->dentry->d_cookie;
-
-        if (!dcs)
+        if (path->dentry->d_flags & DCACHE_COOKIE) {
+                dcs = find_dcookie((unsigned long)path->dentry);
+        } else {
                 dcs = alloc_dcookie(path);
-
-        if (!dcs) {
-                err = -ENOMEM;
-                goto out;
+                if (!dcs) {
+                        err = -ENOMEM;
+                        goto out;
+                }
         }
 
         *cookie = dcookie_value(dcs);
@@ -251,7 +256,12 @@ out_kmem:
 
 static void free_dcookie(struct dcookie_struct * dcs)
 {
-        dcs->path.dentry->d_cookie = NULL;
+        struct dentry *d = dcs->path.dentry;
+
+        spin_lock(&d->d_lock);
+        d->d_flags &= ~DCACHE_COOKIE;
+        spin_unlock(&d->d_lock);
+
         path_put(&dcs->path);
         kmem_cache_free(dcookie_cache, dcs);
 }