1 files changed, 9 insertions, 0 deletions

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index ffb8df91dc34..821edd30333b 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -54,7 +54,11 @@
 
 #define IDMAP_HASH_SZ          128
 
+/* Default cache timeout is 10 minutes */
+unsigned int nfs_idmap_cache_timeout = 600 * HZ;
+
 struct idmap_hashent {
+        unsigned long ih_expires;
         __u32 ih_id;
         int ih_namelen;
         char ih_name[IDMAP_NAMESZ];
@@ -149,6 +153,8 @@ idmap_lookup_name(struct idmap_hashtable *h, const char *name, size_t len)
 
         if (he->ih_namelen != len || memcmp(he->ih_name, name, len) != 0)
                 return NULL;
+        if (time_after(jiffies, he->ih_expires))
+                return NULL;
         return he;
 }
 
@@ -164,6 +170,8 @@ idmap_lookup_id(struct idmap_hashtable *h, __u32 id)
         struct idmap_hashent *he = idmap_id_hash(h, id);
         if (he->ih_id != id || he->ih_namelen == 0)
                 return NULL;
+        if (time_after(jiffies, he->ih_expires))
+                return NULL;
         return he;
 }
 
@@ -192,6 +200,7 @@ idmap_update_entry(struct idmap_hashent *he, const char *name,
         memcpy(he->ih_name, name, namelen);
         he->ih_name[namelen] = '\0';
         he->ih_namelen = namelen;
+        he->ih_expires = jiffies + nfs_idmap_cache_timeout;
 }
 
 /*