1 files changed, 21 insertions, 4 deletions

diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index 379be678cb7e..70fad69eb959 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -58,17 +58,34 @@ void nfs_fscache_release_client_cookie(struct nfs_client *clp)
 /*
  * Get the cache cookie for an NFS superblock.  We have to handle
  * uniquification here because the cache doesn't do it for us.
+ *
+ * The default uniquifier is just an empty string, but it may be overridden
+ * either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
+ * superblock across an automount point of some nature.
  */
-void nfs_fscache_get_super_cookie(struct super_block *sb,
-                                  struct nfs_parsed_mount_data *data)
+void nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq,
+                                  struct nfs_clone_mount *mntdata)
 {
         struct nfs_fscache_key *key, *xkey;
         struct nfs_server *nfss = NFS_SB(sb);
         struct rb_node **p, *parent;
-        const char *uniq = data->fscache_uniq ?: "";
         int diff, ulen;
 
-        ulen = strlen(uniq);
+        if (uniq) {
+                ulen = strlen(uniq);
+        } else if (mntdata) {
+                struct nfs_server *mnt_s = NFS_SB(mntdata->sb);
+                if (mnt_s->fscache_key) {
+                        uniq = mnt_s->fscache_key->key.uniquifier;
+                        ulen = mnt_s->fscache_key->key.uniq_len;
+                }
+        }
+
+        if (!uniq) {
+                uniq = "";
+                ulen = 1;
+        }
+
         key = kzalloc(sizeof(*key) + ulen, GFP_KERNEL);
         if (!key)
                 return;