LU-8357 nodemap: reclassify nodemap requires active conf lock

A couple of call paths did not take the lock, which led to race
conditions. This patch ensures that those calls are under lock.

Signed-off-by: Kit Westneat <kit.westneat@gmail.com>
Change-Id: I3db8203b0b6d7d02a02cbe1c3ed6c847915d0076
Reviewed-on: http://review.whamcloud.com/21159
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/ptlrpc/nodemap_handler.c b/lustre/ptlrpc/nodemap_handler.c
index e80247a..a416c90 100644 (file)
--- a/lustre/ptlrpc/nodemap_handler.c
+++ b/lustre/ptlrpc/nodemap_handler.c
@@ -777,15 +777,21 @@ int nodemap_add_range_helper(struct nodemap_config *config,
        }
 
        list_add(&range->rn_list, &nodemap->nm_ranges);
-       nm_member_reclassify_nodemap(config->nmc_default_nodemap);
+
+       /* nodemaps have no members if they aren't on the active config */
+       if (config == active_config)
+               nm_member_reclassify_nodemap(config->nmc_default_nodemap);
+
        up_write(&config->nmc_range_tree_lock);
 
        /* if range_id is non-zero, we are loading from disk */
        if (range_id == 0)
                rc = nodemap_idx_range_add(range, nid);
 
-       nm_member_revoke_locks(config->nmc_default_nodemap);
-       nm_member_revoke_locks(nodemap);
+       if (config == active_config) {
+               nm_member_revoke_locks(config->nmc_default_nodemap);
+               nm_member_revoke_locks(nodemap);
+       }
 
 out:
        return rc;
@@ -1375,15 +1381,18 @@ void nodemap_config_dealloc(struct nodemap_config *config)
         */
        list_for_each_entry_safe(nodemap, nodemap_temp, &nodemap_list_head,
                                 nm_list) {
+               mutex_lock(&active_config_lock);
                down_write(&config->nmc_range_tree_lock);
 
-               /* move members to new config */
+               /* move members to new config, requires ac lock */
                nm_member_reclassify_nodemap(nodemap);
                list_for_each_entry_safe(range, range_temp, &nodemap->nm_ranges,
                                         rn_list)
                        range_delete(&config->nmc_range_tree, range);
                up_write(&config->nmc_range_tree_lock);
+               mutex_unlock(&active_config_lock);
 
+               /* putref must be outside of ac lock if nm could be destroyed */
                nodemap_putref(nodemap);
        }
        OBD_FREE_PTR(config);