libdm: enhance tracking of activated LVs

Existing mechanism was not able to trace root volume issue.
Simplify the functionality by using simply using activated flag
and trace the dtree in reverse order.

diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index 7632ae4fdca7447f34c6e86d0112a6671edbca95..c4a22441c87b30fdd96df980269e4496afea77e9 100644 (file)
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
 Version 1.02.181 - 
 ===================================
+  Enhance tracking of activated devices when preloading dm tree.
   Fix bug in construction of cache table line (regression from 1.02.159).
 
 Version 1.02.179 - 11th August 2021

diff --git a/device_mapper/libdm-deptree.c b/device_mapper/libdm-deptree.c
index 4f2d79ee1504a31f8af76de7c974736c22dd1012..a0f386e772d64bc3f0bbfb9eaa9f3f67e5fa0e8b 100644 (file)
--- a/device_mapper/libdm-deptree.c
+++ b/device_mapper/libdm-deptree.c
@@ -330,16 +330,7 @@ struct dm_tree_node {
        dm_node_callback_fn callback;
        void *callback_data;
 
-       /*
-        * TODO:
-        *      Add advanced code which tracks of send ioctls and their
-        *      proper revert operation for more advanced recovery
-        *      Current code serves mostly only to recovery when
-        *      thin pool metadata check fails and command would
-        *      have left active thin data and metadata subvolumes.
-        */
-       struct dm_list activated;       /* Head of activated nodes for preload revert */
-       struct dm_list activated_list;  /* List of activated nodes for preload revert */
+       int activated;                  /* tracks activation during preload */
 };
 
 struct dm_tree {
@@ -374,7 +365,6 @@ struct dm_tree *dm_tree_create(void)
        dtree->root.dtree = dtree;
        dm_list_init(&dtree->root.uses);
        dm_list_init(&dtree->root.used_by);
-       dm_list_init(&dtree->root.activated);
        dtree->skip_lockfs = 0;
        dtree->no_flush = 0;
        dtree->mem = dmem;
@@ -559,7 +549,6 @@ static struct dm_tree_node *_create_dm_tree_node(struct dm_tree *dtree,
 
        dm_list_init(&node->uses);
        dm_list_init(&node->used_by);
-       dm_list_init(&node->activated);
        dm_list_init(&node->props.segs);
 
        dev = MKDEV(info->major, info->minor);
@@ -2187,7 +2176,7 @@ static int _create_node(struct dm_tree_node *dnode, struct dm_tree_node *parent)
        }
 
        if (r)
-               dm_list_add_h(&parent->activated, &dnode->activated_list);
+               dnode->activated = 1;
 out:
        dm_task_destroy(dmt);
 
@@ -3180,26 +3169,29 @@ out:
        return r;
 }
 
-/*
- * Currently try to deactivate only nodes created during preload.
- * New node is always attached to the front of activated_list
- */
-static int _dm_tree_revert_activated(struct dm_tree_node *parent)
+/* Try to deactivate only nodes created during preload. */
+static int _dm_tree_revert_activated(struct dm_tree_node *dnode)
 {
+       void *handle = NULL;
        struct dm_tree_node *child;
 
-       dm_list_iterate_items_gen(child, &parent->activated, activated_list) {
-               log_debug_activation("Reverting %s.", _node_name(child));
-               if (child->callback) {
-                       log_debug_activation("Dropping callback for %s.", _node_name(child));
-                       child->callback = NULL;
-               }
-               if (!_deactivate_node(child->name, child->info.major, child->info.minor,
-                                     &child->dtree->cookie, child->udev_flags, 0)) {
-                       log_error("Unable to deactivate %s.", _node_name(child));
-                       return 0;
+       while ((child = dm_tree_next_child(&handle, dnode, 0))) {
+               if (child->activated) {
+                       if (child->callback) {
+                               log_debug_activation("Dropping callback for %s.", _node_name(child));
+                               child->callback = NULL;
+                       }
+
+                       log_debug_activation("Reverting %s.", _node_name(child));
+                       if (!_deactivate_node(child->name, child->info.major, child->info.minor,
+                                             &child->dtree->cookie, child->udev_flags, 0)) {
+                               log_debug_activation("Unable to deactivate %s.", _node_name(child));
+                               return 0;
+                       }
                }
-               if (!_dm_tree_revert_activated(child))
+
+               if (dm_tree_node_num_children(child, 0) &&
+                   !_dm_tree_revert_activated(child))
                        return_0;
        }
 

diff --git a/libdm/libdm-deptree.c b/libdm/libdm-deptree.c
index 881558e4481a8a402020597992e7a684bba55b0a..d7fb5ef13cbd403056d9f0882c2710b0eed04673 100644 (file)
--- a/libdm/libdm-deptree.c
+++ b/libdm/libdm-deptree.c
@@ -292,16 +292,7 @@ struct dm_tree_node {
        dm_node_callback_fn callback;
        void *callback_data;
 
-       /*
-        * TODO:
-        *      Add advanced code which tracks of send ioctls and their
-        *      proper revert operation for more advanced recovery
-        *      Current code serves mostly only to recovery when
-        *      thin pool metadata check fails and command would
-        *      have left active thin data and metadata subvolumes.
-        */
-       struct dm_list activated;       /* Head of activated nodes for preload revert */
-       struct dm_list activated_list;  /* List of activated nodes for preload revert */
+       int activated;                  /* tracks activation during preload */
 };
 
 struct dm_tree {
@@ -336,7 +327,6 @@ struct dm_tree *dm_tree_create(void)
        dtree->root.dtree = dtree;
        dm_list_init(&dtree->root.uses);
        dm_list_init(&dtree->root.used_by);
-       dm_list_init(&dtree->root.activated);
        dtree->skip_lockfs = 0;
        dtree->no_flush = 0;
        dtree->mem = dmem;
@@ -521,7 +511,6 @@ static struct dm_tree_node *_create_dm_tree_node(struct dm_tree *dtree,
 
        dm_list_init(&node->uses);
        dm_list_init(&node->used_by);
-       dm_list_init(&node->activated);
        dm_list_init(&node->props.segs);
 
        dev = MKDEV(info->major, info->minor);
@@ -2036,7 +2025,7 @@ static int _create_node(struct dm_tree_node *dnode, struct dm_tree_node *parent)
        }
 
        if (r)
-               dm_list_add_h(&parent->activated, &dnode->activated_list);
+               dnode->activated = 1;
 out:
        dm_task_destroy(dmt);
 
@@ -2793,26 +2782,29 @@ out:
        return r;
 }
 
-/*
- * Currently try to deactivate only nodes created during preload.
- * New node is always attached to the front of activated_list
- */
-static int _dm_tree_revert_activated(struct dm_tree_node *parent)
+/* Try to deactivate only nodes created during preload. */
+static int _dm_tree_revert_activated(struct dm_tree_node *dnode)
 {
+       void *handle = NULL;
        struct dm_tree_node *child;
 
-       dm_list_iterate_items_gen(child, &parent->activated, activated_list) {
-               log_debug_activation("Reverting %s.", _node_name(child));
-               if (child->callback) {
-                       log_debug_activation("Dropping callback for %s.", _node_name(child));
-                       child->callback = NULL;
-               }
-               if (!_deactivate_node(child->name, child->info.major, child->info.minor,
-                                     &child->dtree->cookie, child->udev_flags, 0)) {
-                       log_error("Unable to deactivate %s.", _node_name(child));
-                       return 0;
+       while ((child = dm_tree_next_child(&handle, dnode, 0))) {
+               if (child->activated) {
+                       if (child->callback) {
+                               log_debug_activation("Dropping callback for %s.", _node_name(child));
+                               child->callback = NULL;
+                       }
+
+                       log_debug_activation("Reverting %s.", _node_name(child));
+                       if (!_deactivate_node(child->name, child->info.major, child->info.minor,
+                                             &child->dtree->cookie, child->udev_flags, 0)) {
+                               log_debug_activation("Unable to deactivate %s.", _node_name(child));
+                               return 0;
+                       }
                }
-               if (!_dm_tree_revert_activated(child))
+
+               if (dm_tree_node_num_children(child, 0) &&
+                   !_dm_tree_revert_activated(child))
                        return_0;
        }