Updated snapshot indexes in superblock to not depend on index "0" as being

[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 cf03c00..4289bac 100644 (file)
--- a/lustre/include/linux/obd_snap.h
+++ b/lustre/include/linux/obd_snap.h
@@ -4,11 +4,17 @@
 #define OBD_SNAP_MAGIC 0x47224722
 
 #define SNAP_MAX  8 /* must fit in "u" area of struct inode */
+
+/* if time is 0 this designates the "current" snapshot, i.e.
+   the head of the tree 
+*/
+
 struct snap {
        time_t time;
        int index;
 };
 
+/* snap ioctl data for attach */
 struct snap_obd_data {
        int snap_dev;             /* which device contains the data */
        unsigned int snap_no;     /* which snapshot are we accessing */
@@ -16,13 +22,18 @@ struct snap_obd_data {
        struct snap snap_snaps[SNAP_MAX]; /* times must be incr or attach will fail */
 };
 
+
+/* this is the obd device descriptor */
 struct snap_obd {
-       unsigned int snap_no;    /* which snapshot are we accessing */
+       unsigned int snap_no;    /* which snapshot index are we accessing */
+       unsigned int snap_current;
        unsigned int snap_count; /* how many snapshots exist */
        time_t snap_times[SNAP_MAX];
        int snap_index[SNAP_MAX];
 };
 
+
+/* stored as inline data in the objects */
 struct snap_object_data {
        int od_magic;
        /* id of snaps of object; slot 0 has the current data */