snap/snap.c, class/obdcontrol: added support for snapshot restores

[fs/lustre-release.git] / lustre / include / linux / obd_snap.h

diff --git a/lustre/include/linux/obd_snap.h b/lustre/include/linux/obd_snap.h
index 95ea117..e2b79d2 100644 (file)
--- a/lustre/include/linux/obd_snap.h
+++ b/lustre/include/linux/obd_snap.h
@@ -1,8 +1,7 @@
 #ifndef _OBD_SNAP
 #define _OBD_SNAP
 
-#define OBD_SNAP_MAGIC 0x47224722
-
+#define OBD_SNAP_MAGIC 0xfffffff3   /* an unlikely block number */
 
 /* maximum number of snapshot tables we maintain in the kernel */
 #define SNAP_MAX_TABLES 8
@@ -10,12 +9,14 @@
 
 /* maximum number of snapshots per device 
    must fit in "u" area of struct inode */
-#define SNAP_MAX  8 
+#define SNAP_MAX  (EXT2_N_BLOCKS-1)
 
 
-/* ioctls for manipulating snapshots 40 - 50 */
-#define OBD_SNAP_SETTABLE           _IOWR('f', 40, long)
-#define OBD_SNAP_PRINTTABLE           _IOWR('f', 41, long)
+/* ioctls for manipulating snapshots 40 - 60 */
+#define OBD_SNAP_SETTABLE      _IOWR('f', 40, long)
+#define OBD_SNAP_PRINTTABLE    _IOWR('f', 41, long)
+#define OBD_SNAP_DELETE        _IOWR('f', 42, long)
+#define OBD_SNAP_RESTORE       _IOWR('f', 43, long)
 
 
 
@@ -65,12 +66,9 @@ struct snap_obd {
 struct snap_object_data {
        int od_magic;
        /* id of snaps of object; slot 0 has the current data */
-       unsigned long od_ids[SNAP_MAX + 1]; 
+       unsigned long od_ids[SNAP_MAX];
 };
 
-#define        this_snapidx(obd) (obd->u.snap.snap_index)
-
-extern int snap_iocontrol(int cmd, int len, void *karg, void *uarg);
 void snap_use(int table_no, int snap_index) ;
 void snap_unuse(int table_no, int snap_index) ;
 int snap_is_used(int table_no, int snap_index) ;