lvm: Ignore virtual volumes

The sum of the sizes reported by a volume group should equal the size
of the volume group.  Virtual volumes do not directly correspond to
allocated storage (and, in fact, may be larger than the entire volume
group), so must be ignored.

diff --git a/src/lvm.c b/src/lvm.c
index 606acc7..1677f05 100644 (file)
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -49,12 +49,31 @@ static void vg_read(vg_t vg, char const *vg_name)
 {
     struct dm_list *lvs;
     struct lvm_lv_list *lvl;
+    char const *attrs;
 
     lvm_submit (vg_name, "free", lvm_vg_get_free_size(vg));
 
     lvs = lvm_vg_list_lvs(vg);
     dm_list_iterate_items(lvl, lvs) {
-         lvm_submit(vg_name, lvm_lv_get_name(lvl->lv), lvm_lv_get_size(lvl->lv));
+        attrs = lvm_lv_get_attr(lvl->lv);
+        if (attrs == NULL)
+            continue;
+        /* Condition on volume type.  We want the reported sizes in the
+           volume group to sum to the size of the volume group, so we ignore
+           virtual volumes.  */
+        switch (attrs[0]) {
+            case 't':
+                /* Thin pool virtual volume.  We report the underlying data
+                   and metadata volumes, not this one.  Ignore. */
+                continue;
+            case 'v':
+                /* Virtual volume.  Ignore. */
+                continue;
+            case 'V':
+                /* Thin volume or thin snapshot.  Ignore. */
+                continue;
+        }
+        lvm_submit(vg_name, lvm_lv_get_name(lvl->lv), lvm_lv_get_size(lvl->lv));
     }
 }