FIX: Last checkpoint is not initialized on reshape restart

When reshape is restarted and active array in mdmon is being initialized,
mdmon has to know last checkpoint, otherwise reshape will be restarted
form '0' position.
mdadm when reshaped array is assembled stores reshape_position in sysfs
and runs mdmon. Initialize last_checkpoint in active array structure
to value present in sysfs for reshaped array start.

Signed-off-by: Adam Kwolek <adam.kwolek@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/managemon.c b/managemon.c
index 6001f6a9719a56d9ba9f982fe9ceaf2efeb2dfa2..1362a0e9689e3397de139e0e9ab844fa18193a1e 100644 (file)
--- a/managemon.c
+++ b/managemon.c
@@ -596,6 +596,7 @@ static void manage_new(struct mdstat_ent *mdstat,
        char *inst;
        int i;
        int failed = 0;
+       char buf[40];
 
        /* check if array is ready to be monitored */
        if (!mdstat->active)
@@ -657,6 +658,20 @@ static void manage_new(struct mdstat_ent *mdstat,
        dprintf("%s: inst: %d action: %d state: %d\n", __func__, atoi(inst),
                new->action_fd, new->info.state_fd);
 
+       /* reshape_position is set by mdadm in sysfs
+        * read this information for new arrays only (empty victim)
+        */
+       if ((victim == NULL) &&
+           (sysfs_get_str(mdi, NULL, "sync_action", buf, 40) > 0) &&
+           (strncmp(buf, "reshape", 7) == 0)) {
+               if (sysfs_get_ll(mdi, NULL, "reshape_position",
+                       &new->last_checkpoint) != 0)
+                       new->last_checkpoint = 0;
+               dprintf("mdmon: New monitored array is under reshape.\n"
+                       "       Last checkpoint is: %llu\n",
+                       new->last_checkpoint);
+       }
+
        sysfs_free(mdi);
 
        /* if everything checks out tell the metadata handler we want to