2 files changed, 32 insertions, 0 deletions

diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 2b933ce064dd..576f51f4dc52 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -103,6 +103,9 @@ struct cb_sequenceres {
         uint32_t                        csr_target_highestslotid;
 };
 
+extern unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
+                                       struct cb_sequenceres *res);
+
 #endif /* CONFIG_NFS_V4_1 */
 
 extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res);
@@ -119,6 +122,7 @@ extern void nfs_callback_down(int minorversion);
  * of slots for the backchannel.
  */
 #define NFS41_BC_MIN_CALLBACKS 1
+#define NFS41_BC_MAX_CALLBACKS 1
 
 extern unsigned int nfs_callback_set_tcpport;
 extern unsigned short nfs_callback_tcpport;
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index f7e83e23cf9f..f731bbe7ac6a 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -101,3 +101,31 @@ out:
         dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
         return res;
 }
+
+#if defined(CONFIG_NFS_V4_1)
+
+/* FIXME: validate args->cbs_{sequence,slot}id */
+/* FIXME: referring calls should be processed */
+unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
+                                struct cb_sequenceres *res)
+{
+        int i;
+        unsigned status = 0;
+
+        for (i = 0; i < args->csa_nrclists; i++)
+                kfree(args->csa_rclists[i].rcl_refcalls);
+        kfree(args->csa_rclists);
+
+        memcpy(&res->csr_sessionid, &args->csa_sessionid,
+               sizeof(res->csr_sessionid));
+        res->csr_sequenceid = args->csa_sequenceid;
+        res->csr_slotid = args->csa_slotid;
+        res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
+        res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
+
+        dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
+        res->csr_status = status;
+        return status;
+}
+
+#endif /* CONFIG_NFS_V4_1 */